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[PATCH OLK-6.6] net/sched: sch_qfq: Fix null-deref in agg_dequeue
by Dong Chenchen 30 Jan '26

30 Jan '26

From: Xiang Mei <xmei5(a)asu.edu> mainline inclusion from mainline-v6.16-rc6 commit dd831ac8221e691e9e918585b1003c7071df0379 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/7786 CVE: CVE-2025-40083 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- To prevent a potential crash in agg_dequeue (net/sched/sch_qfq.c) when cl->qdisc->ops->peek(cl->qdisc) returns NULL, we check the return value before using it, similar to the existing approach in sch_hfsc.c. To avoid code duplication, the following changes are made: 1. Changed qdisc_warn_nonwc(include/net/pkt_sched.h) into a static inline function. 2. Moved qdisc_peek_len from net/sched/sch_hfsc.c to include/net/pkt_sched.h so that sch_qfq can reuse it. 3. Applied qdisc_peek_len in agg_dequeue to avoid crashing. Signed-off-by: Xiang Mei <xmei5(a)asu.edu> Reviewed-by: Cong Wang <xiyou.wangcong(a)gmail.com> Link: https://patch.msgid.link/20250705212143.3982664-1-xmei5@asu.edu Signed-off-by: Paolo Abeni <pabeni(a)redhat.com> Signed-off-by: Dong Chenchen <dongchenchen2(a)huawei.com> --- include/net/pkt_sched.h | 25 ++++++++++++++++++++++++- net/sched/sch_api.c | 10 ---------- net/sched/sch_hfsc.c | 16 ---------------- net/sched/sch_qfq.c | 2 +- 4 files changed, 25 insertions(+), 28 deletions(-) diff --git a/include/net/pkt_sched.h b/include/net/pkt_sched.h index 15960564e0c3..4d72d24b1f33 100644 --- a/include/net/pkt_sched.h +++ b/include/net/pkt_sched.h @@ -112,7 +112,6 @@ struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r, struct netlink_ext_ack *extack); void qdisc_put_rtab(struct qdisc_rate_table *tab); void qdisc_put_stab(struct qdisc_size_table *tab); -void qdisc_warn_nonwc(const char *txt, struct Qdisc *qdisc); bool sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q, struct net_device *dev, struct netdev_queue *txq, spinlock_t *root_lock, bool validate); @@ -306,4 +305,28 @@ static inline bool tc_qdisc_stats_dump(struct Qdisc *sch, return true; } +static inline void qdisc_warn_nonwc(const char *txt, struct Qdisc *qdisc) +{ + if (!(qdisc->flags & TCQ_F_WARN_NONWC)) { + pr_warn("%s: %s qdisc %X: is non-work-conserving?\n", + txt, qdisc->ops->id, qdisc->handle >> 16); + qdisc->flags |= TCQ_F_WARN_NONWC; + } +} + +static inline unsigned int qdisc_peek_len(struct Qdisc *sch) +{ + struct sk_buff *skb; + unsigned int len; + + skb = sch->ops->peek(sch); + if (unlikely(skb == NULL)) { + qdisc_warn_nonwc("qdisc_peek_len", sch); + return 0; + } + len = qdisc_pkt_len(skb); + + return len; +} + #endif diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c index 13055d6069b3..ff7bad762496 100644 --- a/net/sched/sch_api.c +++ b/net/sched/sch_api.c @@ -599,16 +599,6 @@ void __qdisc_calculate_pkt_len(struct sk_buff *skb, qdisc_skb_cb(skb)->pkt_len = pkt_len; } -void qdisc_warn_nonwc(const char *txt, struct Qdisc *qdisc) -{ - if (!(qdisc->flags & TCQ_F_WARN_NONWC)) { - pr_warn("%s: %s qdisc %X: is non-work-conserving?\n", - txt, qdisc->ops->id, qdisc->handle >> 16); - qdisc->flags |= TCQ_F_WARN_NONWC; - } -} -EXPORT_SYMBOL(qdisc_warn_nonwc); - static enum hrtimer_restart qdisc_watchdog(struct hrtimer *timer) { struct qdisc_watchdog *wd = container_of(timer, struct qdisc_watchdog, diff --git a/net/sched/sch_hfsc.c b/net/sched/sch_hfsc.c index afcb83d469ff..751b1e2c35b3 100644 --- a/net/sched/sch_hfsc.c +++ b/net/sched/sch_hfsc.c @@ -835,22 +835,6 @@ update_vf(struct hfsc_class *cl, unsigned int len, u64 cur_time) } } -static unsigned int -qdisc_peek_len(struct Qdisc *sch) -{ - struct sk_buff *skb; - unsigned int len; - - skb = sch->ops->peek(sch); - if (unlikely(skb == NULL)) { - qdisc_warn_nonwc("qdisc_peek_len", sch); - return 0; - } - len = qdisc_pkt_len(skb); - - return len; -} - static void hfsc_adjust_levels(struct hfsc_class *cl) { diff --git a/net/sched/sch_qfq.c b/net/sched/sch_qfq.c index 042200066a79..a9db57d29739 100644 --- a/net/sched/sch_qfq.c +++ b/net/sched/sch_qfq.c @@ -1002,7 +1002,7 @@ static struct sk_buff *agg_dequeue(struct qfq_aggregate *agg, if (cl->qdisc->q.qlen == 0) /* no more packets, remove from list */ list_del_init(&cl->alist); - else if (cl->deficit < qdisc_pkt_len(cl->qdisc->ops->peek(cl->qdisc))) { + else if (cl->deficit < qdisc_peek_len(cl->qdisc)) { cl->deficit += agg->lmax; list_move_tail(&cl->alist, &agg->active); } -- 2.25.1

2 1

[PATCH OLK-6.6] bpf: Reject narrower access to pointer ctx fields
by Dong Chenchen 30 Jan '26

30 Jan '26

From: Paul Chaignon <paul.chaignon(a)gmail.com> mainline inclusion from mainline-v6.17-rc1 commit e09299225d5ba3916c91ef70565f7d2187e4cca0 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/12429 CVE: CVE-2025-38591 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- The following BPF program, simplified from a syzkaller repro, causes a kernel warning: r0 = *(u8 *)(r1 + 169); exit; With pointer field sk being at offset 168 in __sk_buff. This access is detected as a narrower read in bpf_skb_is_valid_access because it doesn't match offsetof(struct __sk_buff, sk). It is therefore allowed and later proceeds to bpf_convert_ctx_access. Note that for the "is_narrower_load" case in the convert_ctx_accesses(), the insn->off is aligned, so the cnt may not be 0 because it matches the offsetof(struct __sk_buff, sk) in the bpf_convert_ctx_access. However, the target_size stays 0 and the verifier errors with a kernel warning: verifier bug: error during ctx access conversion(1) This patch fixes that to return a proper "invalid bpf_context access off=X size=Y" error on the load instruction. The same issue affects multiple other fields in context structures that allow narrow access. Some other non-affected fields (for sk_msg, sk_lookup, and sockopt) were also changed to use bpf_ctx_range_ptr for consistency. Note this syzkaller crash was reported in the "Closes" link below, which used to be about a different bug, fixed in commit fce7bd8e385a ("bpf/verifier: Handle BPF_LOAD_ACQ instructions in insn_def_regno()"). Because syzbot somehow confused the two bugs, the new crash and repro didn't get reported to the mailing list. Fixes: f96da09473b52 ("bpf: simplify narrower ctx access") Fixes: 0df1a55afa832 ("bpf: Warn on internal verifier errors") Reported-by: syzbot+0ef84a7bdf5301d4cbec(a)syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=0ef84a7bdf5301d4cbec Signed-off-by: Paul Chaignon <paul.chaignon(a)gmail.com> Signed-off-by: Martin KaFai Lau <martin.lau(a)kernel.org> Acked-by: Eduard Zingerman <eddyz87(a)gmail.com> Link: https://patch.msgid.link/3b8dcee67ff4296903351a974ddd9c4dca768b64.175319459… Signed-off-by: Dong Chenchen <dongchenchen2(a)huawei.com> --- kernel/bpf/cgroup.c | 8 ++++---- net/core/filter.c | 20 ++++++++++---------- 2 files changed, 14 insertions(+), 14 deletions(-) diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c index 90cc73c762cf..1082f5906967 100644 --- a/kernel/bpf/cgroup.c +++ b/kernel/bpf/cgroup.c @@ -2446,22 +2446,22 @@ static bool cg_sockopt_is_valid_access(int off, int size, } switch (off) { - case offsetof(struct bpf_sockopt, sk): + case bpf_ctx_range_ptr(struct bpf_sockopt, sk): if (size != sizeof(__u64)) return false; info->reg_type = PTR_TO_SOCKET; break; - case offsetof(struct bpf_sockopt, optval): + case bpf_ctx_range_ptr(struct bpf_sockopt, optval): if (size != sizeof(__u64)) return false; info->reg_type = PTR_TO_PACKET; break; - case offsetof(struct bpf_sockopt, optval_end): + case bpf_ctx_range_ptr(struct bpf_sockopt, optval_end): if (size != sizeof(__u64)) return false; info->reg_type = PTR_TO_PACKET_END; break; - case offsetof(struct bpf_sockopt, retval): + case bpf_ctx_range(struct bpf_sockopt, retval): if (size != size_default) return false; return prog->expected_attach_type == BPF_CGROUP_GETSOCKOPT; diff --git a/net/core/filter.c b/net/core/filter.c index c9d4910f3f55..b706fc1260b0 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -8678,7 +8678,7 @@ static bool bpf_skb_is_valid_access(int off, int size, enum bpf_access_type type if (size != sizeof(__u64)) return false; break; - case offsetof(struct __sk_buff, sk): + case bpf_ctx_range_ptr(struct __sk_buff, sk): if (type == BPF_WRITE || size != sizeof(__u64)) return false; info->reg_type = PTR_TO_SOCK_COMMON_OR_NULL; @@ -9282,7 +9282,7 @@ static bool sock_addr_is_valid_access(int off, int size, return false; } break; - case offsetof(struct bpf_sock_addr, sk): + case bpf_ctx_range_ptr(struct bpf_sock_addr, sk): if (type != BPF_READ) return false; if (size != sizeof(__u64)) @@ -9337,17 +9337,17 @@ static bool sock_ops_is_valid_access(int off, int size, if (size != sizeof(__u64)) return false; break; - case offsetof(struct bpf_sock_ops, sk): + case bpf_ctx_range_ptr(struct bpf_sock_ops, sk): if (size != sizeof(__u64)) return false; info->reg_type = PTR_TO_SOCKET_OR_NULL; break; - case offsetof(struct bpf_sock_ops, skb_data): + case bpf_ctx_range_ptr(struct bpf_sock_ops, skb_data): if (size != sizeof(__u64)) return false; info->reg_type = PTR_TO_PACKET; break; - case offsetof(struct bpf_sock_ops, skb_data_end): + case bpf_ctx_range_ptr(struct bpf_sock_ops, skb_data_end): if (size != sizeof(__u64)) return false; info->reg_type = PTR_TO_PACKET_END; @@ -9356,7 +9356,7 @@ static bool sock_ops_is_valid_access(int off, int size, bpf_ctx_record_field_size(info, size_default); return bpf_ctx_narrow_access_ok(off, size, size_default); - case offsetof(struct bpf_sock_ops, skb_hwtstamp): + case bpf_ctx_range(struct bpf_sock_ops, skb_hwtstamp): if (size != sizeof(__u64)) return false; break; @@ -9426,17 +9426,17 @@ static bool sk_msg_is_valid_access(int off, int size, return false; switch (off) { - case offsetof(struct sk_msg_md, data): + case bpf_ctx_range_ptr(struct sk_msg_md, data): info->reg_type = PTR_TO_PACKET; if (size != sizeof(__u64)) return false; break; - case offsetof(struct sk_msg_md, data_end): + case bpf_ctx_range_ptr(struct sk_msg_md, data_end): info->reg_type = PTR_TO_PACKET_END; if (size != sizeof(__u64)) return false; break; - case offsetof(struct sk_msg_md, sk): + case bpf_ctx_range_ptr(struct sk_msg_md, sk): if (size != sizeof(__u64)) return false; info->reg_type = PTR_TO_SOCKET; @@ -11665,7 +11665,7 @@ static bool sk_lookup_is_valid_access(int off, int size, return false; switch (off) { - case offsetof(struct bpf_sk_lookup, sk): + case bpf_ctx_range_ptr(struct bpf_sk_lookup, sk): info->reg_type = PTR_TO_SOCKET_OR_NULL; return size == sizeof(__u64); -- 2.25.1

2 1

[PATCH OLK-6.6] Bluetooth: eir: Fix possible crashes on eir_create_adv_data
by Dong Chenchen 30 Jan '26

30 Jan '26

From: Luiz Augusto von Dentz <luiz.von.dentz(a)intel.com> mainline inclusion from mainline-v6.16-rc2 commit 47c03902269aff377f959dc3fd94a9733aa31d6e category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/9488 CVE: CVE-2025-38303 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- eir_create_adv_data may attempt to add EIR_FLAGS and EIR_TX_POWER without checking if that would fit. Link: https://github.com/bluez/bluez/issues/1117#issuecomment-2958244066 Fixes: 01ce70b0a274 ("Bluetooth: eir: Move EIR/Adv Data functions to its own file") Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz(a)intel.com> Conflicts: net/bluetooth/eir.h net/bluetooth/hci_sync.c [commit e77f43d531af and 5f60d5f6bbc1 are not backport] Signed-off-by: Dong Chenchen <dongchenchen2(a)huawei.com> --- net/bluetooth/eir.c | 7 ++++--- net/bluetooth/eir.h | 2 +- net/bluetooth/hci_sync.c | 5 +++-- 3 files changed, 8 insertions(+), 6 deletions(-) diff --git a/net/bluetooth/eir.c b/net/bluetooth/eir.c index 3e1713673ecc..3f72111ba651 100644 --- a/net/bluetooth/eir.c +++ b/net/bluetooth/eir.c @@ -242,7 +242,7 @@ u8 eir_create_per_adv_data(struct hci_dev *hdev, u8 instance, u8 *ptr) return ad_len; } -u8 eir_create_adv_data(struct hci_dev *hdev, u8 instance, u8 *ptr) +u8 eir_create_adv_data(struct hci_dev *hdev, u8 instance, u8 *ptr, u8 size) { struct adv_info *adv = NULL; u8 ad_len = 0, flags = 0; @@ -286,7 +286,7 @@ u8 eir_create_adv_data(struct hci_dev *hdev, u8 instance, u8 *ptr) /* If flags would still be empty, then there is no need to * include the "Flags" AD field". */ - if (flags) { + if (flags && (ad_len + eir_precalc_len(1) <= size)) { ptr[0] = 0x02; ptr[1] = EIR_FLAGS; ptr[2] = flags; @@ -316,7 +316,8 @@ u8 eir_create_adv_data(struct hci_dev *hdev, u8 instance, u8 *ptr) } /* Provide Tx Power only if we can provide a valid value for it */ - if (adv_tx_power != HCI_TX_POWER_INVALID) { + if (adv_tx_power != HCI_TX_POWER_INVALID && + (ad_len + eir_precalc_len(1) <= size)) { ptr[0] = 0x02; ptr[1] = EIR_TX_POWER; ptr[2] = (u8)adv_tx_power; diff --git a/net/bluetooth/eir.h b/net/bluetooth/eir.h index 0df19f2f4af9..4497f8fd5fef 100644 --- a/net/bluetooth/eir.h +++ b/net/bluetooth/eir.h @@ -9,7 +9,7 @@ void eir_create(struct hci_dev *hdev, u8 *data); -u8 eir_create_adv_data(struct hci_dev *hdev, u8 instance, u8 *ptr); +u8 eir_create_adv_data(struct hci_dev *hdev, u8 instance, u8 *ptr, u8 size); u8 eir_create_scan_rsp(struct hci_dev *hdev, u8 instance, u8 *ptr); u8 eir_create_per_adv_data(struct hci_dev *hdev, u8 instance, u8 *ptr); diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c index cdd4e8ac8991..44e15af4410a 100644 --- a/net/bluetooth/hci_sync.c +++ b/net/bluetooth/hci_sync.c @@ -1883,7 +1883,8 @@ static int hci_set_ext_adv_data_sync(struct hci_dev *hdev, u8 instance) return 0; } - len = eir_create_adv_data(hdev, instance, pdu.data); + len = eir_create_adv_data(hdev, instance, pdu.data, + HCI_MAX_EXT_AD_LENGTH); pdu.cp.length = len; pdu.cp.handle = instance; @@ -1914,7 +1915,7 @@ static int hci_set_adv_data_sync(struct hci_dev *hdev, u8 instance) memset(&cp, 0, sizeof(cp)); - len = eir_create_adv_data(hdev, instance, cp.data); + len = eir_create_adv_data(hdev, instance, cp.data, sizeof(cp.data)); /* There's nothing to do if the data hasn't changed */ if (hdev->adv_data_len == len && -- 2.25.1

2 1

[PATCH OLK-6.6] IB/mlx5: Fix potential deadlock in MR deregistration
by Dong Chenchen 30 Jan '26

30 Jan '26

From: Or Har-Toov <ohartoov(a)nvidia.com> mainline inclusion from mainline-v6.16-rc5 commit 2ed25aa7f7711f508b6120e336f05cd9d49943c0 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/9417 CVE: CVE-2025-38373 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- The issue arises when kzalloc() is invoked while holding umem_mutex or any other lock acquired under umem_mutex. This is problematic because kzalloc() can trigger fs_reclaim_aqcuire(), which may, in turn, invoke mmu_notifier_invalidate_range_start(). This function can lead to mlx5_ib_invalidate_range(), which attempts to acquire umem_mutex again, resulting in a deadlock. The problematic flow: CPU0 | CPU1 ---------------------------------------|------------------------------------------------ mlx5_ib_dereg_mr() | → revoke_mr() | → mutex_lock(&umem_odp->umem_mutex) | | mlx5_mkey_cache_init() | → mutex_lock(&dev->cache.rb_lock) | → mlx5r_cache_create_ent_locked() | → kzalloc(GFP_KERNEL) | → fs_reclaim() | → mmu_notifier_invalidate_range_start() | → mlx5_ib_invalidate_range() | → mutex_lock(&umem_odp->umem_mutex) → cache_ent_find_and_store() | → mutex_lock(&dev->cache.rb_lock) | Additionally, when kzalloc() is called from within cache_ent_find_and_store(), we encounter the same deadlock due to re-acquisition of umem_mutex. Solve by releasing umem_mutex in dereg_mr() after umr_revoke_mr() and before acquiring rb_lock. This ensures that we don't hold umem_mutex while performing memory allocations that could trigger the reclaim path. This change prevents the deadlock by ensuring proper lock ordering and avoiding holding locks during memory allocation operations that could trigger the reclaim path. The following lockdep warning demonstrates the deadlock: python3/20557 is trying to acquire lock: ffff888387542128 (&umem_odp->umem_mutex){+.+.}-{4:4}, at: mlx5_ib_invalidate_range+0x5b/0x550 [mlx5_ib] but task is already holding lock: ffffffff82f6b840 (mmu_notifier_invalidate_range_start){+.+.}-{0:0}, at: unmap_vmas+0x7b/0x1a0 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (mmu_notifier_invalidate_range_start){+.+.}-{0:0}: fs_reclaim_acquire+0x60/0xd0 mem_cgroup_css_alloc+0x6f/0x9b0 cgroup_init_subsys+0xa4/0x240 cgroup_init+0x1c8/0x510 start_kernel+0x747/0x760 x86_64_start_reservations+0x25/0x30 x86_64_start_kernel+0x73/0x80 common_startup_64+0x129/0x138 -> #2 (fs_reclaim){+.+.}-{0:0}: fs_reclaim_acquire+0x91/0xd0 __kmalloc_cache_noprof+0x4d/0x4c0 mlx5r_cache_create_ent_locked+0x75/0x620 [mlx5_ib] mlx5_mkey_cache_init+0x186/0x360 [mlx5_ib] mlx5_ib_stage_post_ib_reg_umr_init+0x3c/0x60 [mlx5_ib] __mlx5_ib_add+0x4b/0x190 [mlx5_ib] mlx5r_probe+0xd9/0x320 [mlx5_ib] auxiliary_bus_probe+0x42/0x70 really_probe+0xdb/0x360 __driver_probe_device+0x8f/0x130 driver_probe_device+0x1f/0xb0 __driver_attach+0xd4/0x1f0 bus_for_each_dev+0x79/0xd0 bus_add_driver+0xf0/0x200 driver_register+0x6e/0xc0 __auxiliary_driver_register+0x6a/0xc0 do_one_initcall+0x5e/0x390 do_init_module+0x88/0x240 init_module_from_file+0x85/0xc0 idempotent_init_module+0x104/0x300 __x64_sys_finit_module+0x68/0xc0 do_syscall_64+0x6d/0x140 entry_SYSCALL_64_after_hwframe+0x4b/0x53 -> #1 (&dev->cache.rb_lock){+.+.}-{4:4}: __mutex_lock+0x98/0xf10 __mlx5_ib_dereg_mr+0x6f2/0x890 [mlx5_ib] mlx5_ib_dereg_mr+0x21/0x110 [mlx5_ib] ib_dereg_mr_user+0x85/0x1f0 [ib_core] uverbs_free_mr+0x19/0x30 [ib_uverbs] destroy_hw_idr_uobject+0x21/0x80 [ib_uverbs] uverbs_destroy_uobject+0x60/0x3d0 [ib_uverbs] uobj_destroy+0x57/0xa0 [ib_uverbs] ib_uverbs_cmd_verbs+0x4d5/0x1210 [ib_uverbs] ib_uverbs_ioctl+0x129/0x230 [ib_uverbs] __x64_sys_ioctl+0x596/0xaa0 do_syscall_64+0x6d/0x140 entry_SYSCALL_64_after_hwframe+0x4b/0x53 -> #0 (&umem_odp->umem_mutex){+.+.}-{4:4}: __lock_acquire+0x1826/0x2f00 lock_acquire+0xd3/0x2e0 __mutex_lock+0x98/0xf10 mlx5_ib_invalidate_range+0x5b/0x550 [mlx5_ib] __mmu_notifier_invalidate_range_start+0x18e/0x1f0 unmap_vmas+0x182/0x1a0 exit_mmap+0xf3/0x4a0 mmput+0x3a/0x100 do_exit+0x2b9/0xa90 do_group_exit+0x32/0xa0 get_signal+0xc32/0xcb0 arch_do_signal_or_restart+0x29/0x1d0 syscall_exit_to_user_mode+0x105/0x1d0 do_syscall_64+0x79/0x140 entry_SYSCALL_64_after_hwframe+0x4b/0x53 Chain exists of: &dev->cache.rb_lock --> mmu_notifier_invalidate_range_start --> &umem_odp->umem_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&umem_odp->umem_mutex); lock(mmu_notifier_invalidate_range_start); lock(&umem_odp->umem_mutex); lock(&dev->cache.rb_lock); *** DEADLOCK *** Fixes: abb604a1a9c8 ("RDMA/mlx5: Fix a race for an ODP MR which leads to CQE with error") Signed-off-by: Or Har-Toov <ohartoov(a)nvidia.com> Reviewed-by: Michael Guralnik <michaelgur(a)nvidia.com> Link: https://patch.msgid.link/3c8f225a8a9fade647d19b014df1172544643e4a.175006161… Signed-off-by: Leon Romanovsky <leon(a)kernel.org> Conflicts: drivers/infiniband/hw/mlx5/mr.c [commit cc668a11e6ac is not backport] Signed-off-by: Dong Chenchen <dongchenchen2(a)huawei.com> --- drivers/infiniband/hw/mlx5/mr.c | 36 +++++++++++++++++++++++++-------- 1 file changed, 28 insertions(+), 8 deletions(-) diff --git a/drivers/infiniband/hw/mlx5/mr.c b/drivers/infiniband/hw/mlx5/mr.c index 5881d8e69aa4..22aa33550465 100644 --- a/drivers/infiniband/hw/mlx5/mr.c +++ b/drivers/infiniband/hw/mlx5/mr.c @@ -1873,18 +1873,35 @@ static int cache_ent_find_and_store(struct mlx5_ib_dev *dev, return ret; } -static int mlx5_revoke_mr(struct mlx5_ib_mr *mr) +static int mlx5_umr_revoke_mr_with_lock(struct mlx5_ib_mr *mr) { - struct mlx5_ib_dev *dev = to_mdev(mr->ibmr.device); - struct mlx5_cache_ent *ent = mr->mmkey.cache_ent; bool is_odp = is_odp_mr(mr); - int ret = 0; + int ret; if (is_odp) mutex_lock(&to_ib_umem_odp(mr->umem)->umem_mutex); - if (mr->mmkey.cacheable && !mlx5r_umr_revoke_mr(mr) && !cache_ent_find_and_store(dev, mr)) - goto out; + ret = mlx5r_umr_revoke_mr(mr); + + if (is_odp) { + if (!ret) + to_ib_umem_odp(mr->umem)->private = NULL; + mutex_unlock(&to_ib_umem_odp(mr->umem)->umem_mutex); + } + + return ret; +} + +static int mlx5r_handle_mkey_cleanup(struct mlx5_ib_mr *mr) +{ + struct mlx5_ib_dev *dev = to_mdev(mr->ibmr.device); + struct mlx5_cache_ent *ent = mr->mmkey.cache_ent; + bool is_odp = is_odp_mr(mr); + int ret; + + if (mr->mmkey.cacheable && !mlx5_umr_revoke_mr_with_lock(mr) && + !cache_ent_find_and_store(dev, mr)) + return 0; if (ent) { xa_lock_irq(&ent->mkeys); @@ -1892,8 +1909,11 @@ static int mlx5_revoke_mr(struct mlx5_ib_mr *mr) mr->mmkey.cache_ent = NULL; xa_unlock_irq(&ent->mkeys); } + + if (is_odp) + mutex_lock(&to_ib_umem_odp(mr->umem)->umem_mutex); + ret = destroy_mkey(dev, mr); -out: if (is_odp) { if (!ret) to_ib_umem_odp(mr->umem)->private = NULL; @@ -1948,7 +1968,7 @@ int mlx5_ib_dereg_mr(struct ib_mr *ibmr, struct ib_udata *udata) } /* Stop DMA */ - rc = mlx5_revoke_mr(mr); + rc = mlx5r_handle_mkey_cleanup(mr); if (rc) return rc; -- 2.25.1

2 1

[PATCH OLK-6.6 v3 00/21] net: LTS-6.6 backport
by Dong Chenchen 30 Jan '26

30 Jan '26

net lts patches backport Aakash Kumar S (1): xfrm: Duplicate SPI Handling Bui Quang Minh (1): virtio-net: fix received length check in big packets David Howells (1): rxrpc: Fix recv-recv race of completed call Florian Westphal (1): netfilter: nf_reject: don't leak dst refcount for loopback packets Jakub Kicinski (3): tls: handle data disappearing from under the TLS ULP tls: make sure to abort the stream if headers are bogus page_pool: always add GFP_NOWARN for ATOMIC allocations Jiayuan Chen (1): bpf, ktls: Fix data corruption when using bpf_msg_pop_data() in ktls Kuniyuki Iwashima (1): Bluetooth: hci_core: Fix use-after-free in vhci_flush() Maher Azzouzi (1): net/sched: mqprio: fix stack out-of-bounds write in tc entry parsing Marc Kleine-Budde (4): can: dev: can_restart(): reverse logic to remove need for goto can: dev: can_restart(): move debug message and stats after successful restart can: netlink: can_changelink(): fix NULL pointer deref of struct can_priv::do_set_mode can: netlink: can_changelink(): allow disabling of automatic restart Michal Luczaj (3): vsock: Fix transport_{g2h,h2g} TOCTOU vsock: Fix transport_* TOCTOU vsock: Ignore signal/timeout on connect() if already established Nikolay Aleksandrov (1): net: bridge: fix use-after-free due to MST port state bypass Nishanth Menon (1): net: ethernet: ti: netcp: Standardize knav_dma_open_channel to return NULL on error Sabrina Dubroca (1): xfrm: xfrm_alloc_spi shouldn't use 0 as SPI William Liu (1): net/sched: Return NULL when htb_lookup_leaf encounters an empty rbtree drivers/net/can/dev/dev.c | 31 +++++---- drivers/net/can/dev/netlink.c | 16 ++++- drivers/net/ethernet/ti/netcp_core.c | 10 +-- drivers/net/virtio_net.c | 25 ++++---- drivers/soc/ti/knav_dma.c | 14 ++-- include/net/bluetooth/hci_core.h | 1 + include/trace/events/rxrpc.h | 3 + net/bluetooth/hci_core.c | 34 ++++++++-- net/bridge/br_forward.c | 2 +- net/bridge/br_input.c | 4 +- net/bridge/br_private.h | 8 ++- net/core/page_pool.c | 6 ++ net/ipv4/netfilter/nf_reject_ipv4.c | 6 +- net/ipv6/netfilter/nf_reject_ipv6.c | 5 +- net/rxrpc/call_accept.c | 1 + net/rxrpc/recvmsg.c | 19 +++++- net/sched/sch_htb.c | 4 +- net/sched/sch_mqprio.c | 2 +- net/tls/tls.h | 3 +- net/tls/tls_strp.c | 25 +++++--- net/tls/tls_sw.c | 19 +++++- net/vmw_vsock/af_vsock.c | 95 ++++++++++++++++++++++------ net/xfrm/xfrm_state.c | 75 +++++++++++++--------- 23 files changed, 286 insertions(+), 122 deletions(-) -- 2.25.1

2 22

[PATCH OLK-6.6] vfs: Don't leak disconnected dentries on umount
by Zizhi Wo 30 Jan '26

30 Jan '26

From: Jan Kara <jack(a)suse.cz> stable inclusion from stable-v6.6.114 commit cebfbf40056a4d858b2a3ca59a69936d599bd209 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/7768 CVE: CVE-2025-40105 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit 56094ad3eaa21e6621396cc33811d8f72847a834 ] When user calls open_by_handle_at() on some inode that is not cached, we will create disconnected dentry for it. If such dentry is a directory, exportfs_decode_fh_raw() will then try to connect this dentry to the dentry tree through reconnect_path(). It may happen for various reasons (such as corrupted fs or race with rename) that the call to lookup_one_unlocked() in reconnect_one() will fail to find the dentry we are trying to reconnect and instead create a new dentry under the parent. Now this dentry will not be marked as disconnected although the parent still may well be disconnected (at least in case this inconsistency happened because the fs is corrupted and .. doesn't point to the real parent directory). This creates inconsistency in disconnected flags but AFAICS it was mostly harmless. At least until commit f1ee616214cb ("VFS: don't keep disconnected dentries on d_anon") which removed adding of most disconnected dentries to sb->s_anon list. Thus after this commit cleanup of disconnected dentries implicitely relies on the fact that dput() will immediately reclaim such dentries. However when some leaf dentry isn't marked as disconnected, as in the scenario described above, the reclaim doesn't happen and the dentries are "leaked". Memory reclaim can eventually reclaim them but otherwise they stay in memory and if umount comes first, we hit infamous "Busy inodes after unmount" bug. Make sure all dentries created under a disconnected parent are marked as disconnected as well. Reported-by: syzbot+1d79ebe5383fc016cf07(a)syzkaller.appspotmail.com Fixes: f1ee616214cb ("VFS: don't keep disconnected dentries on d_anon") CC: stable(a)vger.kernel.org Signed-off-by: Jan Kara <jack(a)suse.cz> Signed-off-by: Christian Brauner <brauner(a)kernel.org> [ relocated DCACHE_DISCONNECTED propagation from d_alloc_parallel() to d_alloc() ] Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Conflicts: fs/dcache.c [Simple context conflicts, adapted directly.] Signed-off-by: Zizhi Wo <wozizhi(a)huawei.com> --- fs/dcache.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/dcache.c b/fs/dcache.c index fe9140b0d0eb..d7a0672d04f7 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -1948,6 +1948,8 @@ struct dentry *d_alloc(struct dentry * parent, const struct qstr *name) __dget_dlock(parent); dentry->d_parent = parent; list_add(&dentry->d_child, &parent->d_subdirs); + if (parent->d_flags & DCACHE_DISCONNECTED) + dentry->d_flags |= DCACHE_DISCONNECTED; spin_unlock(&parent->d_lock); out: return dentry; -- 2.39.2

2 1

[PATCH OLK-6.6 0/2] *** fix CVE-2025-38062 ***
by Lin Ruifeng 29 Jan '26

29 Jan '26

*** fix CVE-2025-38062 *** Jason Gunthorpe (1): genirq/msi: Store the IOMMU IOVA directly in msi_desc instead of iommu_cookie Lin Ruifeng (1): genirq/msi:: Fix kabi break of struct msi_desc drivers/iommu/dma-iommu.c | 28 +++++++++++++--------------- include/linux/msi.h | 35 +++++++++++++++-------------------- 2 files changed, 28 insertions(+), 35 deletions(-) -- 2.43.0

2 3

[PATCH OLK-5.10] drm/radeon: delete radeon_fence_process in is_signaled, no deadlock
by Lin Ruifeng 29 Jan '26

29 Jan '26

From: Robert McClinton <rbmccav(a)gmail.com> stable inclusion from stable-v6.12.60 commit 73bc12d6a547f9571ce4393acfd73c004e2df9e5 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/11558 CVE: CVE-2025-68223 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- commit 9eb00b5f5697bd56baa3222c7a1426fa15bacfb5 upstream. Delete the attempt to progress the queue when checking if fence is signaled. This avoids deadlock. dma-fence_ops::signaled can be called with the fence lock in unknown state. For radeon, the fence lock is also the wait queue lock. This can cause a self deadlock when signaled() tries to make forward progress on the wait queue. But advancing the queue is unneeded because incorrectly returning false from signaled() is perfectly acceptable. Link: https://github.com/brave/brave-browser/issues/49182 Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4641 Cc: Alex Deucher <alexander.deucher(a)amd.com> Signed-off-by: Robert McClinton <rbmccav(a)gmail.com> Signed-off-by: Alex Deucher <alexander.deucher(a)amd.com> (cherry picked from commit 527ba26e50ec2ca2be9c7c82f3ad42998a75d0db) Cc: stable(a)vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Conflicts: drivers/gpu/drm/radeon/radeon_fence.c [Context Conflicts] Signed-off-by: Lin Ruifeng <linruifeng4(a)huawei.com> --- drivers/gpu/drm/radeon/radeon_fence.c | 8 -------- 1 file changed, 8 deletions(-) diff --git a/drivers/gpu/drm/radeon/radeon_fence.c b/drivers/gpu/drm/radeon/radeon_fence.c index 8735bf2bb8b5..b6210460f39b 100644 --- a/drivers/gpu/drm/radeon/radeon_fence.c +++ b/drivers/gpu/drm/radeon/radeon_fence.c @@ -370,14 +370,6 @@ static bool radeon_fence_is_signaled(struct dma_fence *f) return true; } - if (down_read_trylock(&rdev->exclusive_lock)) { - radeon_fence_process(rdev, ring); - up_read(&rdev->exclusive_lock); - - if (atomic64_read(&rdev->fence_drv[ring].last_seq) >= seq) { - return true; - } - } return false; } -- 2.43.0

2 1

[PATCH OLK-6.6] gfs2: Prevent recursive memory reclaim
by Lin Ruifeng 29 Jan '26

29 Jan '26

From: Andreas Gruenbacher <agruenba(a)redhat.com> stable inclusion from stable-v6.12.63 commit edb2b255618621dc83d0ec23150e16b2c697077f category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/12714 CVE: CVE-2025-68356 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit 2c5f4a53476e3cab70adc77b38942c066bd2c17c ] Function new_inode() returns a new inode with inode->i_mapping->gfp_mask set to GFP_HIGHUSER_MOVABLE. This value includes the __GFP_FS flag, so allocations in that address space can recurse into filesystem memory reclaim. We don't want that to happen because it can consume a significant amount of stack memory. Worse than that is that it can also deadlock: for example, in several places, gfs2_unstuff_dinode() is called inside filesystem transactions. This calls filemap_grab_folio(), which can allocate a new folio, which can trigger memory reclaim. If memory reclaim recurses into the filesystem and starts another transaction, a deadlock will ensue. To fix these kinds of problems, prevent memory reclaim from recursing into filesystem code by making sure that the gfp_mask of inode address spaces doesn't include __GFP_FS. The "meta" and resource group address spaces were already using GFP_NOFS as their gfp_mask (which doesn't include __GFP_FS). The default value of GFP_HIGHUSER_MOVABLE is less restrictive than GFP_NOFS, though. To avoid being overly limiting, use the default value and only knock off the __GFP_FS flag. I'm not sure if this will actually make a difference, but it also shouldn't hurt. This patch is loosely based on commit ad22c7a043c2 ("xfs: prevent stack overflows from page cache allocation"). Fixes xfstest generic/273. Fixes: dc0b9435238c ("gfs: Don't use GFP_NOFS in gfs2_unstuff_dinode") Reviewed-by: Andrew Price <anprice(a)redhat.com> Signed-off-by: Andreas Gruenbacher <agruenba(a)redhat.com> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Conflicts: fs/gfs2/glock.c fs/gfs2/ops_fstype.c [Context Conflicts] Signed-off-by: Lin Ruifeng <linruifeng4(a)huawei.com> --- fs/gfs2/glock.c | 5 ++++- fs/gfs2/inode.c | 15 +++++++++++++++ fs/gfs2/inode.h | 1 + fs/gfs2/ops_fstype.c | 2 +- 4 files changed, 21 insertions(+), 2 deletions(-) diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c index 7606e983a2ca..8fb9f1bba384 100644 --- a/fs/gfs2/glock.c +++ b/fs/gfs2/glock.c @@ -1254,10 +1254,13 @@ int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number, mapping = gfs2_glock2aspace(gl); if (mapping) { + gfp_t gfp_mask; + mapping->a_ops = &gfs2_meta_aops; mapping->host = s->s_bdev->bd_inode; mapping->flags = 0; - mapping_set_gfp_mask(mapping, GFP_NOFS); + gfp_mask = mapping_gfp_mask(&sdp->sd_aspace); + mapping_set_gfp_mask(mapping, gfp_mask); mapping->private_data = NULL; mapping->writeback_index = 0; } diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c index 1cb5ce63fbf6..8627c85c6bf0 100644 --- a/fs/gfs2/inode.c +++ b/fs/gfs2/inode.c @@ -89,6 +89,19 @@ static int iget_set(struct inode *inode, void *opaque) return 0; } +void gfs2_setup_inode(struct inode *inode) +{ + gfp_t gfp_mask; + + /* + * Ensure all page cache allocations are done from GFP_NOFS context to + * prevent direct reclaim recursion back into the filesystem and blowing + * stacks or deadlocking. + */ + gfp_mask = mapping_gfp_mask(inode->i_mapping); + mapping_set_gfp_mask(inode->i_mapping, gfp_mask & ~__GFP_FS); +} + /** * gfs2_inode_lookup - Lookup an inode * @sb: The super block @@ -132,6 +145,7 @@ struct inode *gfs2_inode_lookup(struct super_block *sb, unsigned int type, struct gfs2_glock *io_gl; int extra_flags = 0; + gfs2_setup_inode(inode); error = gfs2_glock_get(sdp, no_addr, &gfs2_inode_glops, CREATE, &ip->i_gl); if (unlikely(error)) @@ -684,6 +698,7 @@ static int gfs2_create_inode(struct inode *dir, struct dentry *dentry, error = -ENOMEM; if (!inode) goto fail_gunlock; + gfs2_setup_inode(inode); ip = GFS2_I(inode); error = posix_acl_create(dir, &mode, &default_acl, &acl); diff --git a/fs/gfs2/inode.h b/fs/gfs2/inode.h index ce70cf26b497..6f7c9ec21bbf 100644 --- a/fs/gfs2/inode.h +++ b/fs/gfs2/inode.h @@ -88,6 +88,7 @@ static inline int gfs2_check_internal_file_size(struct inode *inode, return -EIO; } +void gfs2_setup_inode(struct inode *inode); struct inode *gfs2_inode_lookup(struct super_block *sb, unsigned type, u64 no_addr, u64 no_formal_ino, unsigned int blktype); diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c index f4c066aa24b9..1f6dd91180e0 100644 --- a/fs/gfs2/ops_fstype.c +++ b/fs/gfs2/ops_fstype.c @@ -116,7 +116,7 @@ static struct gfs2_sbd *init_sbd(struct super_block *sb) mapping->a_ops = &gfs2_rgrp_aops; mapping->host = sb->s_bdev->bd_inode; mapping->flags = 0; - mapping_set_gfp_mask(mapping, GFP_NOFS); + gfs2_setup_inode(mapping->host); mapping->private_data = NULL; mapping->writeback_index = 0; -- 2.43.0

2 1

[PATCH OLK-6.6 0/2] *** fix CVE-2025-38062 ***
by Lin Ruifeng 29 Jan '26

29 Jan '26

*** fix CVE-2025-38062 *** Jason Gunthorpe (1): genirq/msi: Store the IOMMU IOVA directly in msi_desc instead of iommu_cookie Lin Ruifeng (1): genirq/msi:: Fix kabi break of struct msi_desc drivers/iommu/dma-iommu.c | 28 +++++++++++++--------------- include/linux/msi.h | 35 +++++++++++++++-------------------- 2 files changed, 28 insertions(+), 35 deletions(-) -- 2.43.0

2 3

[PATCH OLK-6.6] KVM: SVM: Don't skip unrelated instruction if INT3/INTO is replaced
by Lin Ruifeng 29 Jan '26

29 Jan '26

From: Omar Sandoval <osandov(a)fb.com> stable inclusion from stable-v6.12.62 commit 87cc1622c88a4888959d64fa1fc9ba1e264aa3d4 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/11544 CVE: CVE-2025-68259 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- commit 4da3768e1820cf15cced390242d8789aed34f54d upstream. When re-injecting a soft interrupt from an INT3, INT0, or (select) INTn instruction, discard the exception and retry the instruction if the code stream is changed (e.g. by a different vCPU) between when the CPU executes the instruction and when KVM decodes the instruction to get the next RIP. As effectively predicted by commit 6ef88d6e36c2 ("KVM: SVM: Re-inject INT3/INTO instead of retrying the instruction"), failure to verify that the correct INTn instruction was decoded can effectively clobber guest state due to decoding the wrong instruction and thus specifying the wrong next RIP. The bug most often manifests as "Oops: int3" panics on static branch checks in Linux guests. Enabling or disabling a static branch in Linux uses the kernel's "text poke" code patching mechanism. To modify code while other CPUs may be executing that code, Linux (temporarily) replaces the first byte of the original instruction with an int3 (opcode 0xcc), then patches in the new code stream except for the first byte, and finally replaces the int3 with the first byte of the new code stream. If a CPU hits the int3, i.e. executes the code while it's being modified, then the guest kernel must look up the RIP to determine how to handle the #BP, e.g. by emulating the new instruction. If the RIP is incorrect, then this lookup fails and the guest kernel panics. The bug reproduces almost instantly by hacking the guest kernel to repeatedly check a static branch[1] while running a drgn script[2] on the host to constantly swap out the memory containing the guest's TSS. [1]: https://gist.github.com/osandov/44d17c51c28c0ac998ea0334edf90b5a [2]: https://gist.github.com/osandov/10e45e45afa29b11e0c7209247afc00b Fixes: 6ef88d6e36c2 ("KVM: SVM: Re-inject INT3/INTO instead of retrying the instruction") Cc: stable(a)vger.kernel.org Co-developed-by: Sean Christopherson <seanjc(a)google.com> Signed-off-by: Omar Sandoval <osandov(a)fb.com> Link: https://patch.msgid.link/1cc6dcdf36e3add7ee7c8d90ad58414eeb6c3d34.176227876… Signed-off-by: Sean Christopherson <seanjc(a)google.com> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Conflicts: arch/x86/kvm/svm/svm.c [Context Conflicts] Signed-off-by: Lin Ruifeng <linruifeng4(a)huawei.com> --- arch/x86/include/asm/kvm_host.h | 9 +++++++++ arch/x86/kvm/svm/svm.c | 24 +++++++++++++----------- arch/x86/kvm/x86.c | 21 +++++++++++++++++++++ 3 files changed, 43 insertions(+), 11 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 3936da6febce..e54edd378230 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1974,6 +1974,11 @@ u64 vcpu_tsc_khz(struct kvm_vcpu *vcpu); * the gfn, i.e. retrying the instruction will hit a * !PRESENT fault, which results in a new shadow page * and sends KVM back to square one. + * + * EMULTYPE_SKIP_SOFT_INT - Set in combination with EMULTYPE_SKIP to only skip + * an instruction if it could generate a given software + * interrupt, which must be encoded via + * EMULTYPE_SET_SOFT_INT_VECTOR(). */ #define EMULTYPE_NO_DECODE (1 << 0) #define EMULTYPE_TRAP_UD (1 << 1) @@ -1984,6 +1989,10 @@ u64 vcpu_tsc_khz(struct kvm_vcpu *vcpu); #define EMULTYPE_PF (1 << 6) #define EMULTYPE_COMPLETE_USER_EXIT (1 << 7) #define EMULTYPE_WRITE_PF_TO_SP (1 << 8) +#define EMULTYPE_SKIP_SOFT_INT (1 << 9) + +#define EMULTYPE_SET_SOFT_INT_VECTOR(v) ((u32)((v) & 0xff) << 16) +#define EMULTYPE_GET_SOFT_INT_VECTOR(e) (((e) >> 16) & 0xff) int kvm_emulate_instruction(struct kvm_vcpu *vcpu, int emulation_type); int kvm_emulate_instruction_from_buffer(struct kvm_vcpu *vcpu, diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index dfe7ed5e567f..e6b9118943f1 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -384,6 +384,7 @@ static bool svm_can_emulate_instruction(struct kvm_vcpu *vcpu, int emul_type, void *insn, int insn_len); static int __svm_skip_emulated_instruction(struct kvm_vcpu *vcpu, + int emul_type, bool commit_side_effects) { struct vcpu_svm *svm = to_svm(vcpu); @@ -413,7 +414,7 @@ static int __svm_skip_emulated_instruction(struct kvm_vcpu *vcpu, if (unlikely(!commit_side_effects)) old_rflags = svm->vmcb->save.rflags; - if (!kvm_emulate_instruction(vcpu, EMULTYPE_SKIP)) + if (!kvm_emulate_instruction(vcpu, emul_type)) return 0; if (unlikely(!commit_side_effects)) @@ -431,11 +432,13 @@ static int __svm_skip_emulated_instruction(struct kvm_vcpu *vcpu, static int svm_skip_emulated_instruction(struct kvm_vcpu *vcpu) { - return __svm_skip_emulated_instruction(vcpu, true); + return __svm_skip_emulated_instruction(vcpu, EMULTYPE_SKIP, true); } -static int svm_update_soft_interrupt_rip(struct kvm_vcpu *vcpu) +static int svm_update_soft_interrupt_rip(struct kvm_vcpu *vcpu, u8 vector) { + const int emul_type = EMULTYPE_SKIP | EMULTYPE_SKIP_SOFT_INT | + EMULTYPE_SET_SOFT_INT_VECTOR(vector); unsigned long rip, old_rip = kvm_rip_read(vcpu); struct vcpu_svm *svm = to_svm(vcpu); @@ -451,7 +454,7 @@ static int svm_update_soft_interrupt_rip(struct kvm_vcpu *vcpu) * in use, the skip must not commit any side effects such as clearing * the interrupt shadow or RFLAGS.RF. */ - if (!__svm_skip_emulated_instruction(vcpu, !nrips)) + if (!__svm_skip_emulated_instruction(vcpu, emul_type, !nrips)) return -EIO; rip = kvm_rip_read(vcpu); @@ -487,7 +490,7 @@ static void svm_inject_exception(struct kvm_vcpu *vcpu) kvm_deliver_exception_payload(vcpu, ex); if (kvm_exception_is_soft(ex->vector) && - svm_update_soft_interrupt_rip(vcpu)) + svm_update_soft_interrupt_rip(vcpu, ex->vector)) return; svm->vmcb->control.event_inj = ex->vector @@ -3713,11 +3716,12 @@ static bool svm_set_vnmi_pending(struct kvm_vcpu *vcpu) static void svm_inject_irq(struct kvm_vcpu *vcpu, bool reinjected) { + struct kvm_queued_interrupt *intr = &vcpu->arch.interrupt; struct vcpu_svm *svm = to_svm(vcpu); u32 type; - if (vcpu->arch.interrupt.soft) { - if (svm_update_soft_interrupt_rip(vcpu)) + if (intr->soft) { + if (svm_update_soft_interrupt_rip(vcpu, intr->nr)) return; type = SVM_EVTINJ_TYPE_SOFT; @@ -3725,12 +3729,10 @@ static void svm_inject_irq(struct kvm_vcpu *vcpu, bool reinjected) type = SVM_EVTINJ_TYPE_INTR; } - trace_kvm_inj_virq(vcpu->arch.interrupt.nr, - vcpu->arch.interrupt.soft, reinjected); + trace_kvm_inj_virq(intr->nr, intr->soft, reinjected); ++vcpu->stat.irq_injections; - svm->vmcb->control.event_inj = vcpu->arch.interrupt.nr | - SVM_EVTINJ_VALID | type; + svm->vmcb->control.event_inj = intr->nr | SVM_EVTINJ_VALID | type; } void svm_complete_interrupt_delivery(struct kvm_vcpu *vcpu, int delivery_mode, diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 2139f728aecc..8f4911acde42 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -9023,6 +9023,23 @@ static bool is_vmware_backdoor_opcode(struct x86_emulate_ctxt *ctxt) return false; } +static bool is_soft_int_instruction(struct x86_emulate_ctxt *ctxt, + int emulation_type) +{ + u8 vector = EMULTYPE_GET_SOFT_INT_VECTOR(emulation_type); + + switch (ctxt->b) { + case 0xcc: + return vector == BP_VECTOR; + case 0xcd: + return vector == ctxt->src.val; + case 0xce: + return vector == OF_VECTOR; + default: + return false; + } +} + /* * Decode an instruction for emulation. The caller is responsible for handling * code breakpoints. Note, manually detecting code breakpoints is unnecessary @@ -9113,6 +9130,10 @@ int x86_emulate_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, * injecting single-step #DBs. */ if (emulation_type & EMULTYPE_SKIP) { + if (emulation_type & EMULTYPE_SKIP_SOFT_INT && + !is_soft_int_instruction(ctxt, emulation_type)) + return 0; + if (ctxt->mode != X86EMUL_MODE_PROT64) ctxt->eip = (u32)ctxt->_eip; else -- 2.43.0

2 1

[PATCH OLK-6.6] pinctrl: check the return value of pinmux_ops::get_function_name()
by Lin Ruifeng 29 Jan '26

29 Jan '26

From: Bartosz Golaszewski <bartosz.golaszewski(a)linaro.org> stable inclusion from stable-v6.6.112 commit 1a2ea887a5cd7d47bab599f733d89444df018b1a category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/12323 CVE: CVE-2025-40030 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- commit 4002ee98c022d671ecc1e4a84029e9ae7d8a5603 upstream. While the API contract in docs doesn't specify it explicitly, the generic implementation of the get_function_name() callback from struct pinmux_ops - pinmux_generic_get_function_name() - can fail and return NULL. This is already checked in pinmux_check_ops() so add a similar check in pinmux_func_name_to_selector() instead of passing the returned pointer right down to strcmp() where the NULL can get dereferenced. This is normal operation when adding new pinfunctions. Cc: stable(a)vger.kernel.org Tested-by: Neil Armstrong <neil.armstrong(a)linaro.org> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski(a)linaro.org> Signed-off-by: Linus Walleij <linus.walleij(a)linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Lin Ruifeng <linruifeng4(a)huawei.com> --- drivers/pinctrl/pinmux.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/pinctrl/pinmux.c b/drivers/pinctrl/pinmux.c index ab853d6c586b..1c324d216ad7 100644 --- a/drivers/pinctrl/pinmux.c +++ b/drivers/pinctrl/pinmux.c @@ -339,7 +339,7 @@ static int pinmux_func_name_to_selector(struct pinctrl_dev *pctldev, while (selector < nfuncs) { const char *fname = ops->get_function_name(pctldev, selector); - if (!strcmp(function, fname)) + if (fname && !strcmp(function, fname)) return selector; selector++; -- 2.43.0

2 1

[PATCH OLK-6.6] iommu/amd/pgtbl: Fix possible race while increase page table level
by Lin Ruifeng 29 Jan '26

29 Jan '26

From: Vasant Hegde <vasant.hegde(a)amd.com> stable inclusion from stable-v6.6.108 commit 075abf0b1a958acfbea2435003d228e738e90346 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/7970 CVE: CVE-2025-39961 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit 1e56310b40fd2e7e0b9493da9ff488af145bdd0c ] The AMD IOMMU host page table implementation supports dynamic page table levels (up to 6 levels), starting with a 3-level configuration that expands based on IOVA address. The kernel maintains a root pointer and current page table level to enable proper page table walks in alloc_pte()/fetch_pte() operations. The IOMMU IOVA allocator initially starts with 32-bit address and onces its exhuasted it switches to 64-bit address (max address is determined based on IOMMU and device DMA capability). To support larger IOVA, AMD IOMMU driver increases page table level. But in unmap path (iommu_v1_unmap_pages()), fetch_pte() reads pgtable->[root/mode] without lock. So its possible that in exteme corner case, when increase_address_space() is updating pgtable->[root/mode], fetch_pte() reads wrong page table level (pgtable->mode). It does compare the value with level encoded in page table and returns NULL. This will result is iommu_unmap ops to fail and upper layer may retry/log WARN_ON. CPU 0 CPU 1 ------ ------ map pages unmap pages alloc_pte() -> increase_address_space() iommu_v1_unmap_pages() -> fetch_pte() pgtable->root = pte (new root value) READ pgtable->[mode/root] Reads new root, old mode Updates mode (pgtable->mode += 1) Since Page table level updates are infrequent and already synchronized with a spinlock, implement seqcount to enable lock-free read operations on the read path. Fixes: 754265bcab7 ("iommu/amd: Fix race in increase_address_space()") Reported-by: Alejandro Jimenez <alejandro.j.jimenez(a)oracle.com> Cc: stable(a)vger.kernel.org Cc: Joao Martins <joao.m.martins(a)oracle.com> Cc: Suravee Suthikulpanit <suravee.suthikulpanit(a)amd.com> Signed-off-by: Vasant Hegde <vasant.hegde(a)amd.com> Signed-off-by: Joerg Roedel <joerg.roedel(a)amd.com> [ Adapted pgtable->mode and pgtable->root to use domain->iop.mode and domain->iop.root ] Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Conflicts: drivers/iommu/amd/io_pgtable.c [Context Conflicts] Signed-off-by: Lin Ruifeng <linruifeng4(a)huawei.com> --- drivers/iommu/amd/amd_iommu_types.h | 1 + drivers/iommu/amd/io_pgtable.c | 26 ++++++++++++++++++++++---- 2 files changed, 23 insertions(+), 4 deletions(-) diff --git a/drivers/iommu/amd/amd_iommu_types.h b/drivers/iommu/amd/amd_iommu_types.h index dec4e5c2b66b..be4a5b16b187 100644 --- a/drivers/iommu/amd/amd_iommu_types.h +++ b/drivers/iommu/amd/amd_iommu_types.h @@ -551,6 +551,7 @@ struct amd_irte_ops; container_of((x), struct amd_io_pgtable, pgtbl_cfg) struct amd_io_pgtable { + seqcount_t seqcount; /* Protects root/mode update */ struct io_pgtable_cfg pgtbl_cfg; struct io_pgtable iop; int mode; diff --git a/drivers/iommu/amd/io_pgtable.c b/drivers/iommu/amd/io_pgtable.c index 6c0621f6f572..ca41da139d86 100644 --- a/drivers/iommu/amd/io_pgtable.c +++ b/drivers/iommu/amd/io_pgtable.c @@ -17,6 +17,7 @@ #include <linux/slab.h> #include <linux/types.h> #include <linux/dma-mapping.h> +#include <linux/seqlock.h> #include <asm/barrier.h> @@ -171,8 +172,11 @@ static bool increase_address_space(struct protection_domain *domain, *pte = PM_LEVEL_PDE(domain->iop.mode, iommu_virt_to_phys(domain->iop.root)); + write_seqcount_begin(&domain->iop.seqcount); domain->iop.root = pte; domain->iop.mode += 1; + write_seqcount_end(&domain->iop.seqcount); + amd_iommu_update_and_flush_device_table(domain); amd_iommu_domain_flush_complete(domain); @@ -199,6 +203,7 @@ static u64 *alloc_pte(struct protection_domain *domain, gfp_t gfp, bool *updated) { + unsigned int seqcount; int level, end_lvl; u64 *pte, *page; @@ -214,8 +219,14 @@ static u64 *alloc_pte(struct protection_domain *domain, } - level = domain->iop.mode - 1; - pte = &domain->iop.root[PM_LEVEL_INDEX(level, address)]; + do { + seqcount = read_seqcount_begin(&domain->iop.seqcount); + + level = domain->iop.mode - 1; + pte = &domain->iop.root[PM_LEVEL_INDEX(level, address)]; + } while (read_seqcount_retry(&domain->iop.seqcount, seqcount)); + + address = PAGE_SIZE_ALIGN(address, page_size); end_lvl = PAGE_SIZE_LEVEL(page_size); @@ -292,6 +303,7 @@ static u64 *fetch_pte(struct amd_io_pgtable *pgtable, unsigned long *page_size) { int level; + unsigned int seqcount; u64 *pte; *page_size = 0; @@ -299,8 +311,12 @@ static u64 *fetch_pte(struct amd_io_pgtable *pgtable, if (address > PM_LEVEL_SIZE(pgtable->mode)) return NULL; - level = pgtable->mode - 1; - pte = &pgtable->root[PM_LEVEL_INDEX(level, address)]; + do { + seqcount = read_seqcount_begin(&pgtable->seqcount); + level = pgtable->mode - 1; + pte = &pgtable->root[PM_LEVEL_INDEX(level, address)]; + } while (read_seqcount_retry(&pgtable->seqcount, seqcount)); + *page_size = PTE_LEVEL_PAGE_SIZE(level); while (level > 0) { @@ -591,6 +607,8 @@ static struct io_pgtable *v1_alloc_pgtable(struct io_pgtable_cfg *cfg, void *coo cfg->oas = IOMMU_OUT_ADDR_BIT_SIZE, cfg->tlb = &v1_flush_ops; + seqcount_init(&pgtable->seqcount); + pgtable->iop.ops.map_pages = iommu_v1_map_pages; pgtable->iop.ops.unmap_pages = iommu_v1_unmap_pages; pgtable->iop.ops.iova_to_phys = iommu_v1_iova_to_phys; -- 2.43.0

2 1

[PATCH OLK-5.10] usb: cdns3: fix random warning message when driver load
by Zhang Yuwei 29 Jan '26

29 Jan '26

From: Frank Li <Frank.Li(a)nxp.com> stable inclusion from stable-v5.15.63 commit 8e142744f0e96abc69ccd99e6d6c7eb662267f21 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/10097 CVE: CVE-2022-50151 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit 8659ab3d936fcf0084676f98b75b317017aa8f82 ] Warning log: [ 4.141392] Unexpected gfp: 0x4 (GFP_DMA32). Fixing up to gfp: 0xa20 (GFP_ATOMIC). Fix your code! [ 4.150340] CPU: 1 PID: 175 Comm: 1-0050 Not tainted 5.15.5-00039-g2fd9ae1b568c #20 [ 4.158010] Hardware name: Freescale i.MX8QXP MEK (DT) [ 4.163155] Call trace: [ 4.165600] dump_backtrace+0x0/0x1b0 [ 4.169286] show_stack+0x18/0x68 [ 4.172611] dump_stack_lvl+0x68/0x84 [ 4.176286] dump_stack+0x18/0x34 [ 4.179613] kmalloc_fix_flags+0x60/0x88 [ 4.183550] new_slab+0x334/0x370 [ 4.186878] ___slab_alloc.part.108+0x4d4/0x748 [ 4.191419] __slab_alloc.isra.109+0x30/0x78 [ 4.195702] kmem_cache_alloc+0x40c/0x420 [ 4.199725] dma_pool_alloc+0xac/0x1f8 [ 4.203486] cdns3_allocate_trb_pool+0xb4/0xd0 pool_alloc_page(struct dma_pool *pool, gfp_t mem_flags) { ... page = kmalloc(sizeof(*page), mem_flags); page->vaddr = dma_alloc_coherent(pool->dev, pool->allocation, &page->dma, mem_flags); ... } kmalloc was called with mem_flags, which is passed down in cdns3_allocate_trb_pool() and have GFP_DMA32 flags. kmall_fix_flags() report warning. GFP_DMA32 is not useful at all. dma_alloc_coherent() will handle DMA memory region correctly by pool->dev. GFP_DMA32 can be removed safely. Signed-off-by: Frank Li <Frank.Li(a)nxp.com> Link: https://lore.kernel.org/r/20220609154456.2871672-1-Frank.Li@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Conflicts: drivers/usb/cdns3/gadget.c drivers/usb/cdns3/cdns3-gadget.c [file name is different] Signed-off-by: Guo Mengqi <guomengqi3(a)huawei.com> --- drivers/usb/cdns3/gadget.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/usb/cdns3/gadget.c b/drivers/usb/cdns3/gadget.c index eeea892248b5..2bd24fb806fb 100644 --- a/drivers/usb/cdns3/gadget.c +++ b/drivers/usb/cdns3/gadget.c @@ -237,7 +237,7 @@ int cdns3_allocate_trb_pool(struct cdns3_endpoint *priv_ep) priv_ep->trb_pool = dma_alloc_coherent(priv_dev->sysdev, ring_size, &priv_ep->trb_pool_dma, - GFP_DMA32 | GFP_ATOMIC); + GFP_ATOMIC); if (!priv_ep->trb_pool) return -ENOMEM; -- 2.22.0

2 1

[PATCH OLK-5.10] usb: cdns3: fix random warning message when driver load
by Zhang Yuwei 29 Jan '26

29 Jan '26

From: Frank Li <Frank.Li(a)nxp.com> stable inclusion from stable-v5.15.63 commit 8e142744f0e96abc69ccd99e6d6c7eb662267f21 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/ICG794 CVE: CVE-2022-50151 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit 8659ab3d936fcf0084676f98b75b317017aa8f82 ] Warning log: [ 4.141392] Unexpected gfp: 0x4 (GFP_DMA32). Fixing up to gfp: 0xa20 (GFP_ATOMIC). Fix your code! [ 4.150340] CPU: 1 PID: 175 Comm: 1-0050 Not tainted 5.15.5-00039-g2fd9ae1b568c #20 [ 4.158010] Hardware name: Freescale i.MX8QXP MEK (DT) [ 4.163155] Call trace: [ 4.165600] dump_backtrace+0x0/0x1b0 [ 4.169286] show_stack+0x18/0x68 [ 4.172611] dump_stack_lvl+0x68/0x84 [ 4.176286] dump_stack+0x18/0x34 [ 4.179613] kmalloc_fix_flags+0x60/0x88 [ 4.183550] new_slab+0x334/0x370 [ 4.186878] ___slab_alloc.part.108+0x4d4/0x748 [ 4.191419] __slab_alloc.isra.109+0x30/0x78 [ 4.195702] kmem_cache_alloc+0x40c/0x420 [ 4.199725] dma_pool_alloc+0xac/0x1f8 [ 4.203486] cdns3_allocate_trb_pool+0xb4/0xd0 pool_alloc_page(struct dma_pool *pool, gfp_t mem_flags) { ... page = kmalloc(sizeof(*page), mem_flags); page->vaddr = dma_alloc_coherent(pool->dev, pool->allocation, &page->dma, mem_flags); ... } kmalloc was called with mem_flags, which is passed down in cdns3_allocate_trb_pool() and have GFP_DMA32 flags. kmall_fix_flags() report warning. GFP_DMA32 is not useful at all. dma_alloc_coherent() will handle DMA memory region correctly by pool->dev. GFP_DMA32 can be removed safely. Signed-off-by: Frank Li <Frank.Li(a)nxp.com> Link: https://lore.kernel.org/r/20220609154456.2871672-1-Frank.Li@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Conflicts: drivers/usb/cdns3/gadget.c drivers/usb/cdns3/cdns3-gadget.c [file name is different] Signed-off-by: Guo Mengqi <guomengqi3(a)huawei.com> --- drivers/usb/cdns3/gadget.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/usb/cdns3/gadget.c b/drivers/usb/cdns3/gadget.c index eeea892248b5..2bd24fb806fb 100644 --- a/drivers/usb/cdns3/gadget.c +++ b/drivers/usb/cdns3/gadget.c @@ -237,7 +237,7 @@ int cdns3_allocate_trb_pool(struct cdns3_endpoint *priv_ep) priv_ep->trb_pool = dma_alloc_coherent(priv_dev->sysdev, ring_size, &priv_ep->trb_pool_dma, - GFP_DMA32 | GFP_ATOMIC); + GFP_ATOMIC); if (!priv_ep->trb_pool) return -ENOMEM; -- 2.22.0

2 2

[PATCH v1 openEuler-26.09] Add copy to/from/in user with vectorization support
by Nikita Panov 29 Jan '26

29 Jan '26

From: Artem Kuzin <artem.kuzin(a)huawei.com> kunpeng inclusion category: feature bugzilla: https://atomgit.com/openeuler/kernel/issues/8445 ------------------------------------------------- 1. This implementation uses st1/ld1 4-vector instructions which allow to copy 64 bytes at once 2. Copy code is used only if size of data block to copy is more than 128 bytes 4. To use this functionality you need to set configuration switch CONFIG_USE_VECTORIZED_COPY=y 5. Code can be used on any ARMv8 variant 6. In kernel copy functions like memcpy are not supported now, but can be enabled in future 7. For now we use lightweght version of register context saving/restoration (4-registers) We introduce support of vectorization for copy_from/to/in_user functions. Nowadays it works in parallel with original FPSIMD/SVE vectorization and doesn't affect it anyhow. We have special flag in task struct - TIF_KERNEL_FPSIMD, that set if currently we use lightweight vectorization in kernel. Task struct has been updated by two fields: user space fpsimd state and kernel fpsimd state. User space fpsimd state used by kernel_fpsimd_begin(), kernel_fpsimd_end() functions that wrap lightweight FPSIMD contexts usage in kernel space. Kernel fpsimd state is used to manage threads switch. Now there is no support of nested calls of kernel_neon_begin()/kernel_fpsimd_begin() and there is no plans to support this in future. This is not necessary. We save lightweight FPSIMD context in kernel_fpsimd_begin(), and restore it in /kernel_fpsimd_end(). On thread switch we preserve kernel FPSIMD context and restore user space one if any. This prevens curruption of user space FPSIMD state. Before switching to the next thread we restore it's kernel FPSIMD context if any. It is allowed to use FPSIMD in bottom halves, due to in case of BH preemption we check TIF_KERNEL_FPSIMD flag and save/restore contexts. Context management if quite lightweight and executed only in case of TIF_KERNEL_FPSIMD flag is set. To enable this feature, you need to manually modify one of the appropriate entries: /proc/sys/vm/copy_from_user_threshold /proc/sys/vm/copy_in_user_threshold /proc/sys/vm/copy_to_user_threshold Allowed values are following: -1 - feature enabled 0 - feature always enabled n (n >0) - feature enabled, if copied size is greater than n KB. P.S.: What I am personally don't like in current approach: 1. Additional fields and flag in task struct look quite ugly 2. No way to configure the size of chunk to copy using FPSIMD from user space 3. FPSIMD-based memory movement is not generic, need to enable for memmove(), memcpy() and friends in future. Co-developed-by: Alexander Kozhevnikov <alexander.kozhevnikov(a)huawei-partners.com> Signed-off-by: Alexander Kozhevnikov <alexander.kozhevnikov(a)huawei-partners.com> Co-developed-by: Nikita Panov <panov.nikita(a)huawei.com> Signed-off-by: Nikita Panov <panov.nikita(a)huawei.com> Signed-off-by: Artem Kuzin <artem.kuzin(a)huawei.com> --- arch/arm64/Kconfig | 15 ++ arch/arm64/configs/openeuler_defconfig | 2 + arch/arm64/include/asm/fpsimd.h | 15 ++ arch/arm64/include/asm/fpsimdmacros.h | 14 ++ arch/arm64/include/asm/neon.h | 28 ++++ arch/arm64/include/asm/processor.h | 10 ++ arch/arm64/include/asm/thread_info.h | 5 + arch/arm64/include/asm/uaccess.h | 218 ++++++++++++++++++++++++- arch/arm64/kernel/entry-fpsimd.S | 22 +++ arch/arm64/kernel/fpsimd.c | 102 +++++++++++- arch/arm64/kernel/process.c | 2 +- arch/arm64/lib/copy_from_user.S | 30 ++++ arch/arm64/lib/copy_template_fpsimd.S | 180 ++++++++++++++++++++ arch/arm64/lib/copy_to_user.S | 30 ++++ kernel/softirq.c | 34 ++++ kernel/sysctl.c | 34 ++++ 16 files changed, 734 insertions(+), 7 deletions(-) create mode 100644 arch/arm64/lib/copy_template_fpsimd.S diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index c3b38c890b45..8904e6476e3b 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -1870,6 +1870,21 @@ config ARM64_ILP32 is an ABI where long and pointers are 32bits but it uses the AARCH64 instruction set. +config USE_VECTORIZED_COPY + bool "Use vectorized instructions in copy_to/from user" + depends on KERNEL_MODE_NEON + default y + help + This option turns on vectorization to speed up copy_to/from_user routines. + +config VECTORIZED_COPY_VALIDATE + bool "Validate result of vectorized copy using regular implementation" + depends on KERNEL_MODE_NEON + depends on USE_VECTORIZED_COPY + default n + help + This option turns on vectorization to speed up copy_to/from_user routines. + menuconfig AARCH32_EL0 bool "Kernel support for 32-bit EL0" depends on ARM64_4K_PAGES || EXPERT diff --git a/arch/arm64/configs/openeuler_defconfig b/arch/arm64/configs/openeuler_defconfig index 9e7bc82cba3a..9843dec071bf 100644 --- a/arch/arm64/configs/openeuler_defconfig +++ b/arch/arm64/configs/openeuler_defconfig @@ -527,6 +527,8 @@ CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY=y # CONFIG_RODATA_FULL_DEFAULT_ENABLED is not set # CONFIG_ARM64_SW_TTBR0_PAN is not set CONFIG_ARM64_TAGGED_ADDR_ABI=y +CONFIG_USE_VECTORIZED_COPY=y +# CONFIG_VECTORIZED_COPY_VALIDATE is not set CONFIG_AARCH32_EL0=y # CONFIG_KUSER_HELPERS is not set # CONFIG_COMPAT_ALIGNMENT_FIXUPS is not set diff --git a/arch/arm64/include/asm/fpsimd.h b/arch/arm64/include/asm/fpsimd.h index b6c6949984d8..1fc9089b4a47 100644 --- a/arch/arm64/include/asm/fpsimd.h +++ b/arch/arm64/include/asm/fpsimd.h @@ -46,6 +46,21 @@ struct task_struct; +#ifdef CONFIG_USE_VECTORIZED_COPY +extern void fpsimd_save_state_light(struct fpsimd_state *state); +extern void fpsimd_load_state_light(struct fpsimd_state *state); +#else +static inline void fpsimd_save_state_light(struct fpsimd_state *state) +{ + (void) state; +} + +static inline void fpsimd_load_state_light(struct fpsimd_state *state) +{ + (void) state; +} +#endif + extern void fpsimd_save_state(struct user_fpsimd_state *state); extern void fpsimd_load_state(struct user_fpsimd_state *state); diff --git a/arch/arm64/include/asm/fpsimdmacros.h b/arch/arm64/include/asm/fpsimdmacros.h index cdf6a35e3994..df9d3ed91931 100644 --- a/arch/arm64/include/asm/fpsimdmacros.h +++ b/arch/arm64/include/asm/fpsimdmacros.h @@ -8,6 +8,20 @@ #include <asm/assembler.h> +#ifdef CONFIG_USE_VECTORIZED_COPY +/* Lightweight fpsimd context saving/restoration. + * Necessary for vectorized kernel memory movement + * implementation + */ +.macro fpsimd_save_light state + st1 {v20.16b, v21.16b, v22.16b, v23.16b}, [\state] +.endm + +.macro fpsimd_restore_light state + ld1 {v20.16b, v21.16b, v22.16b, v23.16b}, [\state] +.endm +#endif + .macro fpsimd_save state, tmpnr stp q0, q1, [\state, #16 * 0] stp q2, q3, [\state, #16 * 2] diff --git a/arch/arm64/include/asm/neon.h b/arch/arm64/include/asm/neon.h index d4b1d172a79b..ab84b194d7b3 100644 --- a/arch/arm64/include/asm/neon.h +++ b/arch/arm64/include/asm/neon.h @@ -16,4 +16,32 @@ void kernel_neon_begin(void); void kernel_neon_end(void); +#ifdef CONFIG_USE_VECTORIZED_COPY +bool kernel_fpsimd_begin(void); +void kernel_fpsimd_end(void); +/* Functions to use in non-preemptible context */ +void _kernel_fpsimd_save(struct fpsimd_state *state); +void _kernel_fpsimd_load(struct fpsimd_state *state); +#else +bool kernel_fpsimd_begin(void) +{ + return false; +} + +void kernel_fpsimd_end(void) +{ +} + +/* Functions to use in non-preemptible context */ +void _kernel_fpsimd_save(struct fpsimd_state *state) +{ + (void) state; +} + +void _kernel_fpsimd_load(struct fpsimd_state *state) +{ + (void) state; +} +#endif + #endif /* ! __ASM_NEON_H */ diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h index 9e688b1b13d4..9b81dbcd2126 100644 --- a/arch/arm64/include/asm/processor.h +++ b/arch/arm64/include/asm/processor.h @@ -153,6 +153,10 @@ struct cpu_context { unsigned long pc; }; +struct fpsimd_state { + __uint128_t v[4]; +}; + struct thread_struct { struct cpu_context cpu_context; /* cpu context */ @@ -196,6 +200,12 @@ struct thread_struct { KABI_RESERVE(6) KABI_RESERVE(7) KABI_RESERVE(8) +#ifdef CONFIG_USE_VECTORIZED_COPY + KABI_EXTEND( + struct fpsimd_state ustate; + struct fpsimd_state kstate; + ) +#endif }; static inline unsigned int thread_get_vl(struct thread_struct *thread, diff --git a/arch/arm64/include/asm/thread_info.h b/arch/arm64/include/asm/thread_info.h index 379d24059f5b..60d0be8a2d58 100644 --- a/arch/arm64/include/asm/thread_info.h +++ b/arch/arm64/include/asm/thread_info.h @@ -89,6 +89,9 @@ void arch_setup_new_exec(void); #define TIF_SME 27 /* SME in use */ #define TIF_SME_VL_INHERIT 28 /* Inherit SME vl_onexec across exec */ #define TIF_32BIT_AARCH64 29 /* 32 bit process on AArch64(ILP32) */ +#define TIF_KERNEL_FPSIMD 31 /* Use FPSIMD in kernel */ +#define TIF_PRIV_UACC_ENABLED 32 /* Whether priviliged uaccess was manually enabled */ + #define _TIF_SIGPENDING (1 << TIF_SIGPENDING) #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) @@ -107,6 +110,8 @@ void arch_setup_new_exec(void); #define _TIF_MTE_ASYNC_FAULT (1 << TIF_MTE_ASYNC_FAULT) #define _TIF_NOTIFY_SIGNAL (1 << TIF_NOTIFY_SIGNAL) #define _TIF_32BIT_AARCH64 (1 << TIF_32BIT_AARCH64) +#define _TIF_KERNEL_FPSIMD (1 << TIF_KERNEL_FPSIMD) +#define _TIF_PRIV_UACC_ENABLED (1 << TIF_PRIV_UACC_ENABLED) #define _TIF_WORK_MASK (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \ _TIF_NOTIFY_RESUME | _TIF_FOREIGN_FPSTATE | \ diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h index dd0877a75922..fc9f1a40624d 100644 --- a/arch/arm64/include/asm/uaccess.h +++ b/arch/arm64/include/asm/uaccess.h @@ -26,6 +26,10 @@ #include <asm/memory.h> #include <asm/extable.h> +#ifndef __GENKSYMS__ +#include <asm/neon.h> +#endif + static inline int __access_ok(const void __user *ptr, unsigned long size); /* @@ -134,7 +138,7 @@ static inline void __uaccess_enable_hw_pan(void) CONFIG_ARM64_PAN)); } -static inline void uaccess_disable_privileged(void) +static inline void __uaccess_disable_privileged(void) { mte_disable_tco(); @@ -144,7 +148,22 @@ static inline void uaccess_disable_privileged(void) __uaccess_enable_hw_pan(); } -static inline void uaccess_enable_privileged(void) +static inline void uaccess_disable_privileged(void) +{ + preempt_disable(); + + if (!test_and_clear_thread_flag(TIF_PRIV_UACC_ENABLED)) { + WARN_ON(1); + preempt_enable(); + return; + } + + __uaccess_disable_privileged(); + + preempt_enable(); +} + +static inline void __uaccess_enable_privileged(void) { mte_enable_tco(); @@ -154,6 +173,47 @@ static inline void uaccess_enable_privileged(void) __uaccess_disable_hw_pan(); } +static inline void uaccess_enable_privileged(void) +{ + preempt_disable(); + + if (test_and_set_thread_flag(TIF_PRIV_UACC_ENABLED)) { + WARN_ON(1); + preempt_enable(); + return; + } + + __uaccess_enable_privileged(); + + preempt_enable(); +} + +static inline void uaccess_priviliged_context_switch(struct task_struct *next) +{ + bool curr_enabled = !!test_thread_flag(TIF_PRIV_UACC_ENABLED); + bool next_enabled = !!test_ti_thread_flag(&next->thread_info, TIF_PRIV_UACC_ENABLED); + + if (curr_enabled == next_enabled) + return; + + if (curr_enabled) + __uaccess_disable_privileged(); + else + __uaccess_enable_privileged(); +} + +static inline void uaccess_priviliged_state_save(void) +{ + if (test_thread_flag(TIF_PRIV_UACC_ENABLED)) + __uaccess_disable_privileged(); +} + +static inline void uaccess_priviliged_state_restore(void) +{ + if (test_thread_flag(TIF_PRIV_UACC_ENABLED)) + __uaccess_enable_privileged(); +} + /* * Sanitize a uaccess pointer such that it cannot reach any kernel address. * @@ -391,7 +451,97 @@ do { \ } while (0); \ } while(0) -extern unsigned long __must_check __arch_copy_from_user(void *to, const void __user *from, unsigned long n); +#define USER_COPY_CHUNK_SIZE 4096 + +#ifdef CONFIG_USE_VECTORIZED_COPY + +extern int sysctl_copy_from_user_threshold; + +#define verify_fpsimd_copy(to, from, n, ret) \ +({ \ + unsigned long __verify_ret = 0; \ + __verify_ret = memcmp(to, from, ret ? n - ret : n); \ + if (__verify_ret) \ + pr_err("FPSIMD:%s inconsistent state\n", __func__); \ + if (ret) \ + pr_err("FPSIMD:%s failed to copy data, expected=%lu, copied=%lu\n", __func__, n, n - ret); \ + __verify_ret |= ret; \ + __verify_ret; \ +}) + +#define compare_fpsimd_copy(to, from, n, ret_fpsimd, ret) \ +({ \ + unsigned long __verify_ret = 0; \ + __verify_ret = memcmp(to, from, ret ? n - ret : n); \ + if (__verify_ret) \ + pr_err("FIXUP:%s inconsistent state\n", __func__); \ + if (ret) \ + pr_err("FIXUP:%s failed to copy data, expected=%lu, copied=%lu\n", __func__, n, n - ret); \ + __verify_ret |= ret; \ + if (ret_fpsimd != ret) { \ + pr_err("FIXUP:%s difference between FPSIMD %lu and regular %lu\n", __func__, n - ret_fpsimd, n - ret); \ + __verify_ret |= 1; \ + } else { \ + __verify_ret = 0; \ + } \ + __verify_ret; \ +}) + +extern unsigned long __must_check +__arch_copy_from_user(void *to, const void __user *from, unsigned long n); + +extern unsigned long __must_check +__arch_copy_from_user_fpsimd(void *to, const void __user *from, unsigned long n); + +static __always_inline unsigned long __must_check +raw_copy_from_user(void *to, const void __user *from, unsigned long n) +{ + unsigned long __acfu_ret; + + if (sysctl_copy_from_user_threshold == -1 || n < sysctl_copy_from_user_threshold) { + uaccess_ttbr0_enable(); + __acfu_ret = __arch_copy_from_user(to, + __uaccess_mask_ptr(from), n); + uaccess_ttbr0_disable(); + } else { + if (kernel_fpsimd_begin()) { + unsigned long __acfu_ret_fpsimd; + + uaccess_enable_privileged(); + __acfu_ret_fpsimd = __arch_copy_from_user_fpsimd((to), + __uaccess_mask_ptr(from), n); + uaccess_disable_privileged(); + + __acfu_ret = __acfu_ret_fpsimd; + kernel_fpsimd_end(); +#ifdef CONFIG_VECTORIZED_COPY_VALIDATE + if (verify_fpsimd_copy(to, __uaccess_mask_ptr(from), n, + __acfu_ret)) { + + uaccess_ttbr0_enable(); + __acfu_ret = __arch_copy_from_user((to), + __uaccess_mask_ptr(from), n); + uaccess_ttbr0_disable(); + + compare_fpsimd_copy(to, __uaccess_mask_ptr(from), n, + __acfu_ret_fpsimd, __acfu_ret); + } +#endif + } else { + uaccess_ttbr0_enable(); + __acfu_ret = __arch_copy_from_user((to), + __uaccess_mask_ptr(from), n); + uaccess_ttbr0_disable(); + } + } + + + return __acfu_ret; +} +#else +extern unsigned long __must_check +__arch_copy_from_user(void *to, const void __user *from, unsigned long n); + #define raw_copy_from_user(to, from, n) \ ({ \ unsigned long __acfu_ret; \ @@ -402,7 +552,66 @@ extern unsigned long __must_check __arch_copy_from_user(void *to, const void __u __acfu_ret; \ }) -extern unsigned long __must_check __arch_copy_to_user(void __user *to, const void *from, unsigned long n); +#endif + +#ifdef CONFIG_USE_VECTORIZED_COPY + +extern int sysctl_copy_to_user_threshold; + +extern unsigned long __must_check +__arch_copy_to_user(void __user *to, const void *from, unsigned long n); + +extern unsigned long __must_check +__arch_copy_to_user_fpsimd(void __user *to, const void *from, unsigned long n); + +static __always_inline unsigned long __must_check +raw_copy_to_user(void __user *to, const void *from, unsigned long n) +{ + unsigned long __actu_ret; + + + if (sysctl_copy_to_user_threshold == -1 || n < sysctl_copy_to_user_threshold) { + uaccess_ttbr0_enable(); + __actu_ret = __arch_copy_to_user(__uaccess_mask_ptr(to), + from, n); + uaccess_ttbr0_disable(); + } else { + if (kernel_fpsimd_begin()) { + unsigned long __actu_ret_fpsimd; + + uaccess_enable_privileged(); + __actu_ret_fpsimd = __arch_copy_to_user_fpsimd(__uaccess_mask_ptr(to), + from, n); + uaccess_disable_privileged(); + + kernel_fpsimd_end(); + __actu_ret = __actu_ret_fpsimd; +#ifdef CONFIG_VECTORIZED_COPY_VALIDATE + if (verify_fpsimd_copy(__uaccess_mask_ptr(to), from, n, + __actu_ret)) { + uaccess_ttbr0_enable(); + __actu_ret = __arch_copy_to_user(__uaccess_mask_ptr(to), + from, n); + uaccess_ttbr0_disable(); + + compare_fpsimd_copy(__uaccess_mask_ptr(to), from, n, + __actu_ret_fpsimd, __actu_ret); + } +#endif + } else { + uaccess_ttbr0_enable(); + __actu_ret = __arch_copy_to_user(__uaccess_mask_ptr(to), + from, n); + uaccess_ttbr0_disable(); + } + } + + return __actu_ret; +} +#else +extern unsigned long __must_check +__arch_copy_to_user(void __user *to, const void *from, unsigned long n); + #define raw_copy_to_user(to, from, n) \ ({ \ unsigned long __actu_ret; \ @@ -412,6 +621,7 @@ extern unsigned long __must_check __arch_copy_to_user(void __user *to, const voi uaccess_ttbr0_disable(); \ __actu_ret; \ }) +#endif static __must_check __always_inline bool user_access_begin(const void __user *ptr, size_t len) { diff --git a/arch/arm64/kernel/entry-fpsimd.S b/arch/arm64/kernel/entry-fpsimd.S index 6325db1a2179..6660465f1b7c 100644 --- a/arch/arm64/kernel/entry-fpsimd.S +++ b/arch/arm64/kernel/entry-fpsimd.S @@ -11,6 +11,28 @@ #include <asm/assembler.h> #include <asm/fpsimdmacros.h> +#ifdef CONFIG_USE_VECTORIZED_COPY +/* + * Save the FP registers. + * + * x0 - pointer to struct fpsimd_state_light + */ +SYM_FUNC_START(fpsimd_save_state_light) + fpsimd_save_light x0 + ret +SYM_FUNC_END(fpsimd_save_state_light) + +/* + * Load the FP registers. + * + * x0 - pointer to struct fpsimd_state_light + */ +SYM_FUNC_START(fpsimd_load_state_light) + fpsimd_restore_light x0 + ret +SYM_FUNC_END(fpsimd_load_state_light) +#endif + /* * Save the FP registers. * diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c index 998906b75075..1b6b1accfbbc 100644 --- a/arch/arm64/kernel/fpsimd.c +++ b/arch/arm64/kernel/fpsimd.c @@ -1579,6 +1579,11 @@ void do_fpsimd_exc(unsigned long esr, struct pt_regs *regs) current); } +#ifdef CONFIG_USE_VECTORIZED_COPY +static void kernel_fpsimd_rollback_changes(void); +static void kernel_fpsimd_restore_changes(struct task_struct *tsk); +#endif + void fpsimd_thread_switch(struct task_struct *next) { bool wrong_task, wrong_cpu; @@ -1587,10 +1592,11 @@ void fpsimd_thread_switch(struct task_struct *next) return; __get_cpu_fpsimd_context(); - +#ifdef CONFIG_USE_VECTORIZED_COPY + kernel_fpsimd_rollback_changes(); +#endif /* Save unsaved fpsimd state, if any: */ fpsimd_save(); - /* * Fix up TIF_FOREIGN_FPSTATE to correctly describe next's * state. For kernel threads, FPSIMD registers are never loaded @@ -1603,6 +1609,9 @@ void fpsimd_thread_switch(struct task_struct *next) update_tsk_thread_flag(next, TIF_FOREIGN_FPSTATE, wrong_task || wrong_cpu); +#ifdef CONFIG_USE_VECTORIZED_COPY + kernel_fpsimd_restore_changes(next); +#endif __put_cpu_fpsimd_context(); } @@ -1933,6 +1942,95 @@ void kernel_neon_end(void) } EXPORT_SYMBOL_GPL(kernel_neon_end); +#ifdef CONFIG_USE_VECTORIZED_COPY +bool kernel_fpsimd_begin(void) +{ + if (WARN_ON(!system_capabilities_finalized()) || + !system_supports_fpsimd() || + in_irq() || irqs_disabled() || in_nmi()) + return false; + + preempt_disable(); + if (test_and_set_thread_flag(TIF_KERNEL_FPSIMD)) { + preempt_enable(); + + WARN_ON(1); + return false; + } + + /* + * Leaving streaming mode enabled will cause issues for any kernel + * NEON and leaving streaming mode or ZA enabled may increase power + * consumption. + */ + if (system_supports_sme()) + sme_smstop(); + + fpsimd_save_state_light(&current->thread.ustate); + preempt_enable(); + + return true; +} +EXPORT_SYMBOL(kernel_fpsimd_begin); + +void kernel_fpsimd_end(void) +{ + if (!system_supports_fpsimd()) + return; + + preempt_disable(); + if (test_and_clear_thread_flag(TIF_KERNEL_FPSIMD)) + fpsimd_load_state_light(&current->thread.ustate); + + preempt_enable(); +} +EXPORT_SYMBOL(kernel_fpsimd_end); + +void _kernel_fpsimd_save(struct fpsimd_state *state) +{ + if (!system_supports_fpsimd()) + return; + + BUG_ON(preemptible()); + if (test_thread_flag(TIF_KERNEL_FPSIMD)) + fpsimd_save_state_light(state); +} + +void _kernel_fpsimd_load(struct fpsimd_state *state) +{ + if (!system_supports_fpsimd()) + return; + + BUG_ON(preemptible()); + if (test_thread_flag(TIF_KERNEL_FPSIMD)) + fpsimd_load_state_light(state); +} + +static void kernel_fpsimd_rollback_changes(void) +{ + if (!system_supports_fpsimd()) + return; + + BUG_ON(preemptible()); + if (test_thread_flag(TIF_KERNEL_FPSIMD)) { + fpsimd_save_state_light(&current->thread.kstate); + fpsimd_load_state_light(&current->thread.ustate); + } +} + +static void kernel_fpsimd_restore_changes(struct task_struct *tsk) +{ + if (!system_supports_fpsimd()) + return; + + BUG_ON(preemptible()); + if (test_ti_thread_flag(task_thread_info(tsk), TIF_KERNEL_FPSIMD)) { + fpsimd_save_state_light(&tsk->thread.ustate); + fpsimd_load_state_light(&tsk->thread.kstate); + } +} +#endif + #ifdef CONFIG_EFI static DEFINE_PER_CPU(struct user_fpsimd_state, efi_fpsimd_state); diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c index e9e5ce956f15..fd895189cb7e 100644 --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -529,7 +529,7 @@ struct task_struct *__switch_to(struct task_struct *prev, struct task_struct *next) { struct task_struct *last; - + uaccess_priviliged_context_switch(next); fpsimd_thread_switch(next); tls_thread_switch(next); hw_breakpoint_thread_switch(next); diff --git a/arch/arm64/lib/copy_from_user.S b/arch/arm64/lib/copy_from_user.S index 34e317907524..60dc63e10233 100644 --- a/arch/arm64/lib/copy_from_user.S +++ b/arch/arm64/lib/copy_from_user.S @@ -71,3 +71,33 @@ USER(9998f, ldtrb tmp1w, [srcin]) ret SYM_FUNC_END(__arch_copy_from_user) EXPORT_SYMBOL(__arch_copy_from_user) + + + +#ifdef CONFIG_USE_VECTORIZED_COPY + .macro ldsve reg1, reg2, reg3, reg4, ptr + USER(9997f, ld1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + + .macro stsve reg1, reg2, reg3, reg4, ptr + KERNEL_ME_SAFE(9998f, st1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + +SYM_FUNC_START(__arch_copy_from_user_fpsimd) + add end, x0, x2 + mov srcin, x1 +#include "copy_template_fpsimd.S" + mov x0, #0 // Nothing to copy + ret + + // Exception fixups +9997: cmp dst, dstin + b.ne 9998f + // Before being absolutely sure we couldn't copy anything, try harder +USER(9998f, ldtrb tmp1w, [srcin]) + strb tmp1w, [dst], #1 +9998: sub x0, end, dst // bytes not copied + ret +SYM_FUNC_END(__arch_copy_from_user_fpsimd) +EXPORT_SYMBOL(__arch_copy_from_user_fpsimd) +#endif \ No newline at end of file diff --git a/arch/arm64/lib/copy_template_fpsimd.S b/arch/arm64/lib/copy_template_fpsimd.S new file mode 100644 index 000000000000..9b2e7ce1e4d2 --- /dev/null +++ b/arch/arm64/lib/copy_template_fpsimd.S @@ -0,0 +1,180 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2013 ARM Ltd. + * Copyright (C) 2013 Linaro. + * + * This code is based on glibc cortex strings work originally authored by Linaro + * be found @ + * + * http://bazaar.launchpad.net/~linaro-toolchain-dev/cortex-strings/trunk/ + * files/head:/src/aarch64/ + */ + +/* + * Copy a buffer from src to dest (alignment handled by the hardware) + * + * Parameters: + * x0 - dest + * x1 - src + * x2 - n + * Returns: + * x0 - dest + */ +dstin .req x0 +src .req x1 +count .req x2 +tmp1 .req x3 +tmp1w .req w3 +tmp2 .req x4 +tmp2w .req w4 +dst .req x6 + +A_l .req x7 +A_h .req x8 +B_l .req x9 +B_h .req x10 +C_l .req x11 +C_h .req x12 +D_l .req x13 +D_h .req x14 + +V_a .req v20 +V_b .req v21 +V_c .req v22 +V_d .req v23 + + mov dst, dstin + cmp count, #16 + /*When memory length is less than 16, the accessed are not aligned.*/ + b.lo .Ltiny15_fpsimd + + neg tmp2, src + ands tmp2, tmp2, #15/* Bytes to reach alignment. */ + b.eq .LSrcAligned_fpsimd + sub count, count, tmp2 + /* + * Copy the leading memory data from src to dst in an increasing + * address order.By this way,the risk of overwriting the source + * memory data is eliminated when the distance between src and + * dst is less than 16. The memory accesses here are alignment. + */ + tbz tmp2, #0, 1f + ldrb1 tmp1w, src, #1 + strb1 tmp1w, dst, #1 +1: + tbz tmp2, #1, 2f + ldrh1 tmp1w, src, #2 + strh1 tmp1w, dst, #2 +2: + tbz tmp2, #2, 3f + ldr1 tmp1w, src, #4 + str1 tmp1w, dst, #4 +3: + tbz tmp2, #3, .LSrcAligned_fpsimd + ldr1 tmp1, src, #8 + str1 tmp1, dst, #8 + +.LSrcAligned_fpsimd: + cmp count, #64 + b.ge .Lcpy_over64_fpsimd + /* + * Deal with small copies quickly by dropping straight into the + * exit block. + */ +.Ltail63_fpsimd: + /* + * Copy up to 48 bytes of data. At this point we only need the + * bottom 6 bits of count to be accurate. + */ + ands tmp1, count, #0x30 + b.eq .Ltiny15_fpsimd + cmp tmp1w, #0x20 + b.eq 1f + b.lt 2f + ldp1 A_l, A_h, src, #16 + stp1 A_l, A_h, dst, #16 +1: + ldp1 A_l, A_h, src, #16 + stp1 A_l, A_h, dst, #16 +2: + ldp1 A_l, A_h, src, #16 + stp1 A_l, A_h, dst, #16 +.Ltiny15_fpsimd: + /* + * Prefer to break one ldp/stp into several load/store to access + * memory in an increasing address order,rather than to load/store 16 + * bytes from (src-16) to (dst-16) and to backward the src to aligned + * address,which way is used in original cortex memcpy. If keeping + * the original memcpy process here, memmove need to satisfy the + * precondition that src address is at least 16 bytes bigger than dst + * address,otherwise some source data will be overwritten when memove + * call memcpy directly. To make memmove simpler and decouple the + * memcpy's dependency on memmove, withdrew the original process. + */ + tbz count, #3, 1f + ldr1 tmp1, src, #8 + str1 tmp1, dst, #8 +1: + tbz count, #2, 2f + ldr1 tmp1w, src, #4 + str1 tmp1w, dst, #4 +2: + tbz count, #1, 3f + ldrh1 tmp1w, src, #2 + strh1 tmp1w, dst, #2 +3: + tbz count, #0, .Lexitfunc_fpsimd + ldrb1 tmp1w, src, #1 + strb1 tmp1w, dst, #1 + + b .Lexitfunc_fpsimd + +.Lcpy_over64_fpsimd: + subs count, count, #128 + b.ge .Lcpy_body_large_fpsimd + /* + * Less than 128 bytes to copy, so handle 64 here and then jump + * to the tail. + */ + ldp1 A_l, A_h, src, #16 + stp1 A_l, A_h, dst, #16 + ldp1 B_l, B_h, src, #16 + ldp1 C_l, C_h, src, #16 + stp1 B_l, B_h, dst, #16 + stp1 C_l, C_h, dst, #16 + ldp1 D_l, D_h, src, #16 + stp1 D_l, D_h, dst, #16 + + tst count, #0x3f + b.ne .Ltail63_fpsimd + b .Lexitfunc_fpsimd + + /* + * Critical loop. Start at a new cache line boundary. Assuming + * 64 bytes per line this ensures the entire loop is in one line. + */ + .p2align L1_CACHE_SHIFT +.Lcpy_body_large_fpsimd: + /* pre-get 64 bytes data. */ + ldsve V_a.16b, V_b.16b, V_c.16b, V_d.16b, src + add src, src, #64 + +1: + /* + * interlace the load of next 64 bytes data block with store of the last + * loaded 64 bytes data. + */ + stsve V_a.16b, V_b.16b, V_c.16b, V_d.16b, dst + ldsve V_a.16b, V_b.16b, V_c.16b, V_d.16b, src + add dst, dst, #64 + add src, src, #64 + + subs count, count, #64 + b.ge 1b + + stsve V_a.16b, V_b.16b, V_c.16b, V_d.16b, dst + add dst, dst, #64 + + tst count, #0x3f + b.ne .Ltail63_fpsimd +.Lexitfunc_fpsimd: diff --git a/arch/arm64/lib/copy_to_user.S b/arch/arm64/lib/copy_to_user.S index 2ac716c0d6d8..c190e5f8a989 100644 --- a/arch/arm64/lib/copy_to_user.S +++ b/arch/arm64/lib/copy_to_user.S @@ -71,3 +71,33 @@ USER(9998f, sttrb tmp1w, [dst]) ret SYM_FUNC_END(__arch_copy_to_user) EXPORT_SYMBOL(__arch_copy_to_user) + + +#ifdef CONFIG_USE_VECTORIZED_COPY + .macro stsve reg1, reg2, reg3, reg4, ptr + USER(9997f, st1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + + .macro ldsve reg1, reg2, reg3, reg4, ptr + KERNEL_ME_SAFE(9998f, ld1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + +SYM_FUNC_START(__arch_copy_to_user_fpsimd) + add end, x0, x2 + mov srcin, x1 +#include "copy_template_fpsimd.S" + mov x0, #0 + ret + + // Exception fixups +9997: cmp dst, dstin + b.ne 9998f + // Before being absolutely sure we couldn't copy anything, try harder +KERNEL_ME_SAFE(9998f, ldrb tmp1w, [srcin]) +USER(9998f, sttrb tmp1w, [dst]) + add dst, dst, #1 +9998: sub x0, end, dst // bytes not copied + ret +SYM_FUNC_END(__arch_copy_to_user_fpsimd) +EXPORT_SYMBOL(__arch_copy_to_user_fpsimd) +#endif diff --git a/kernel/softirq.c b/kernel/softirq.c index f8cf88cc46c6..39b84ffbf4e5 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -30,6 +30,10 @@ #include <asm/softirq_stack.h> +#ifdef CONFIG_USE_VECTORIZED_COPY +#include <asm/fpsimd.h> +#endif + #define CREATE_TRACE_POINTS #include <trace/events/irq.h> @@ -524,6 +528,9 @@ static void handle_softirqs(bool ksirqd) __u32 pending; int softirq_bit; +#ifdef CONFIG_USE_VECTORIZED_COPY + struct fpsimd_state state; +#endif /* * Mask out PF_MEMALLOC as the current task context is borrowed for the * softirq. A softirq handled, such as network RX, might set PF_MEMALLOC @@ -533,10 +540,16 @@ static void handle_softirqs(bool ksirqd) pending = local_softirq_pending(); + softirq_handle_begin(); in_hardirq = lockdep_softirq_start(); account_softirq_enter(current); +#ifdef CONFIG_USE_VECTORIZED_COPY + _kernel_fpsimd_save(&state); + uaccess_priviliged_state_save(); +#endif + restart: /* Reset the pending bitmask before enabling irqs */ set_softirq_pending(0); @@ -585,7 +598,14 @@ static void handle_softirqs(bool ksirqd) account_softirq_exit(current); lockdep_softirq_end(in_hardirq); + +#ifdef CONFIG_USE_VECTORIZED_COPY + uaccess_priviliged_state_restore(); + _kernel_fpsimd_load(&state); +#endif + softirq_handle_end(); + current_restore_flags(old_flags, PF_MEMALLOC); } @@ -819,12 +839,21 @@ static void tasklet_action_common(struct softirq_action *a, { struct tasklet_struct *list; +#ifdef CONFIG_USE_VECTORIZED_COPY + struct fpsimd_state state; +#endif + local_irq_disable(); list = tl_head->head; tl_head->head = NULL; tl_head->tail = &tl_head->head; local_irq_enable(); +#ifdef CONFIG_USE_VECTORIZED_COPY + _kernel_fpsimd_save(&state); + uaccess_priviliged_state_save(); +#endif + while (list) { struct tasklet_struct *t = list; @@ -856,6 +885,11 @@ static void tasklet_action_common(struct softirq_action *a, __raise_softirq_irqoff(softirq_nr); local_irq_enable(); } + +#ifdef CONFIG_USE_VECTORIZED_COPY + uaccess_priviliged_state_restore(); + _kernel_fpsimd_load(&state); +#endif } static __latent_entropy void tasklet_action(struct softirq_action *a) diff --git a/kernel/sysctl.c b/kernel/sysctl.c index e84df0818517..6f8e22102bdc 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -137,6 +137,17 @@ int sysctl_legacy_va_layout; #endif /* CONFIG_SYSCTL */ +#ifdef CONFIG_USE_VECTORIZED_COPY +int sysctl_copy_to_user_threshold = -1; +EXPORT_SYMBOL(sysctl_copy_to_user_threshold); + +int sysctl_copy_from_user_threshold = -1; +EXPORT_SYMBOL(sysctl_copy_from_user_threshold); + +int sysctl_copy_in_user_threshold = -1; +EXPORT_SYMBOL(sysctl_copy_in_user_threshold); +#endif + /* * /proc/sys support */ @@ -2250,6 +2261,29 @@ static struct ctl_table vm_table[] = { .extra1 = (void *)&mmap_rnd_compat_bits_min, .extra2 = (void *)&mmap_rnd_compat_bits_max, }, +#endif +#ifdef CONFIG_USE_VECTORIZED_COPY + { + .procname = "copy_to_user_threshold", + .data = &sysctl_copy_to_user_threshold, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec + }, + { + .procname = "copy_from_user_threshold", + .data = &sysctl_copy_from_user_threshold, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec + }, + { + .procname = "copy_in_user_threshold", + .data = &sysctl_copy_in_user_threshold, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec + }, #endif { } }; -- 2.34.1

2 1

[PATCH v1 openEuler-25.03] Add copy to/from/in user with vectorization support
by Nikita Panov 28 Jan '26

28 Jan '26

From: Artem Kuzin <artem.kuzin(a)huawei.com> kunpeng inclusion category: feature bugzilla: https://atomgit.com/openeuler/kernel/issues/8445 ------------------------------------------------- 1. This implementation uses st1/ld1 4-vector instructions which allow to copy 64 bytes at once 2. Copy code is used only if size of data block to copy is more than 128 bytes 4. To use this functionality you need to set configuration switch CONFIG_USE_VECTORIZED_COPY=y 5. Code can be used on any ARMv8 variant 6. In kernel copy functions like memcpy are not supported now, but can be enabled in future 7. For now we use lightweght version of register context saving/restoration (4-registers) We introduce support of vectorization for copy_from/to/in_user functions. Nowadays it works in parallel with original FPSIMD/SVE vectorization and doesn't affect it anyhow. We have special flag in task struct - TIF_KERNEL_FPSIMD, that set if currently we use lightweight vectorization in kernel. Task struct has been updated by two fields: user space fpsimd state and kernel fpsimd state. User space fpsimd state used by kernel_fpsimd_begin(), kernel_fpsimd_end() functions that wrap lightweight FPSIMD contexts usage in kernel space. Kernel fpsimd state is used to manage threads switch. Now there is no support of nested calls of kernel_neon_begin()/kernel_fpsimd_begin() and there is no plans to support this in future. This is not necessary. We save lightweight FPSIMD context in kernel_fpsimd_begin(), and restore it in /kernel_fpsimd_end(). On thread switch we preserve kernel FPSIMD context and restore user space one if any. This prevens curruption of user space FPSIMD state. Before switching to the next thread we restore it's kernel FPSIMD context if any. It is allowed to use FPSIMD in bottom halves, due to in case of BH preemption we check TIF_KERNEL_FPSIMD flag and save/restore contexts. Context management if quite lightweight and executed only in case of TIF_KERNEL_FPSIMD flag is set. To enable this feature, you need to manually modify one of the appropriate entries: /proc/sys/vm/copy_from_user_threshold /proc/sys/vm/copy_in_user_threshold /proc/sys/vm/copy_to_user_threshold Allowed values are following: -1 - feature enabled 0 - feature always enabled n (n >0) - feature enabled, if copied size is greater than n KB. P.S.: What I am personally don't like in current approach: 1. Additional fields and flag in task struct look quite ugly 2. No way to configure the size of chunk to copy using FPSIMD from user space 3. FPSIMD-based memory movement is not generic, need to enable for memmove(), memcpy() and friends in future. Co-developed-by: Alexander Kozhevnikov <alexander.kozhevnikov(a)huawei-partners.com> Signed-off-by: Alexander Kozhevnikov <alexander.kozhevnikov(a)huawei-partners.com> Co-developed-by: Nikita Panov <panov.nikita(a)huawei.com> Signed-off-by: Nikita Panov <panov.nikita(a)huawei.com> Signed-off-by: Artem Kuzin <artem.kuzin(a)huawei.com> --- arch/arm64/Kconfig | 15 ++ arch/arm64/configs/openeuler_defconfig | 2 + arch/arm64/include/asm/fpsimd.h | 15 ++ arch/arm64/include/asm/fpsimdmacros.h | 14 ++ arch/arm64/include/asm/neon.h | 28 ++++ arch/arm64/include/asm/processor.h | 10 ++ arch/arm64/include/asm/thread_info.h | 5 + arch/arm64/include/asm/uaccess.h | 218 ++++++++++++++++++++++++- arch/arm64/kernel/entry-fpsimd.S | 22 +++ arch/arm64/kernel/fpsimd.c | 102 +++++++++++- arch/arm64/kernel/process.c | 2 +- arch/arm64/lib/copy_from_user.S | 30 ++++ arch/arm64/lib/copy_template_fpsimd.S | 180 ++++++++++++++++++++ arch/arm64/lib/copy_to_user.S | 30 ++++ kernel/softirq.c | 34 ++++ kernel/sysctl.c | 34 ++++ 16 files changed, 734 insertions(+), 7 deletions(-) create mode 100644 arch/arm64/lib/copy_template_fpsimd.S diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index d3ce44c166ce..0cf5ab2d7574 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -1828,6 +1828,21 @@ config ARM64_ILP32 is an ABI where long and pointers are 32bits but it uses the AARCH64 instruction set. +config USE_VECTORIZED_COPY + bool "Use vectorized instructions in copy_to/from user" + depends on KERNEL_MODE_NEON + default y + help + This option turns on vectorization to speed up copy_to/from_user routines. + +config VECTORIZED_COPY_VALIDATE + bool "Validate result of vectorized copy using regular implementation" + depends on KERNEL_MODE_NEON + depends on USE_VECTORIZED_COPY + default n + help + This option turns on vectorization to speed up copy_to/from_user routines. + menuconfig AARCH32_EL0 bool "Kernel support for 32-bit EL0" depends on ARM64_4K_PAGES || EXPERT diff --git a/arch/arm64/configs/openeuler_defconfig b/arch/arm64/configs/openeuler_defconfig index 8f97574813ca..dbad22bcbd57 100644 --- a/arch/arm64/configs/openeuler_defconfig +++ b/arch/arm64/configs/openeuler_defconfig @@ -499,6 +499,8 @@ CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY=y # CONFIG_RODATA_FULL_DEFAULT_ENABLED is not set # CONFIG_ARM64_SW_TTBR0_PAN is not set CONFIG_ARM64_TAGGED_ADDR_ABI=y +CONFIG_USE_VECTORIZED_COPY=y +# CONFIG_VECTORIZED_COPY_VALIDATE is not set CONFIG_AARCH32_EL0=y # CONFIG_KUSER_HELPERS is not set # CONFIG_COMPAT_ALIGNMENT_FIXUPS is not set diff --git a/arch/arm64/include/asm/fpsimd.h b/arch/arm64/include/asm/fpsimd.h index 40a99d8607fe..f71b3ac578c1 100644 --- a/arch/arm64/include/asm/fpsimd.h +++ b/arch/arm64/include/asm/fpsimd.h @@ -46,6 +46,21 @@ struct task_struct; +#ifdef CONFIG_USE_VECTORIZED_COPY +extern void fpsimd_save_state_light(struct fpsimd_state *state); +extern void fpsimd_load_state_light(struct fpsimd_state *state); +#else +static inline void fpsimd_save_state_light(struct fpsimd_state *state) +{ + (void) state; +} + +static inline void fpsimd_load_state_light(struct fpsimd_state *state) +{ + (void) state; +} +#endif + extern void fpsimd_save_state(struct user_fpsimd_state *state); extern void fpsimd_load_state(struct user_fpsimd_state *state); diff --git a/arch/arm64/include/asm/fpsimdmacros.h b/arch/arm64/include/asm/fpsimdmacros.h index cdf6a35e3994..df9d3ed91931 100644 --- a/arch/arm64/include/asm/fpsimdmacros.h +++ b/arch/arm64/include/asm/fpsimdmacros.h @@ -8,6 +8,20 @@ #include <asm/assembler.h> +#ifdef CONFIG_USE_VECTORIZED_COPY +/* Lightweight fpsimd context saving/restoration. + * Necessary for vectorized kernel memory movement + * implementation + */ +.macro fpsimd_save_light state + st1 {v20.16b, v21.16b, v22.16b, v23.16b}, [\state] +.endm + +.macro fpsimd_restore_light state + ld1 {v20.16b, v21.16b, v22.16b, v23.16b}, [\state] +.endm +#endif + .macro fpsimd_save state, tmpnr stp q0, q1, [\state, #16 * 0] stp q2, q3, [\state, #16 * 2] diff --git a/arch/arm64/include/asm/neon.h b/arch/arm64/include/asm/neon.h index d4b1d172a79b..ab84b194d7b3 100644 --- a/arch/arm64/include/asm/neon.h +++ b/arch/arm64/include/asm/neon.h @@ -16,4 +16,32 @@ void kernel_neon_begin(void); void kernel_neon_end(void); +#ifdef CONFIG_USE_VECTORIZED_COPY +bool kernel_fpsimd_begin(void); +void kernel_fpsimd_end(void); +/* Functions to use in non-preemptible context */ +void _kernel_fpsimd_save(struct fpsimd_state *state); +void _kernel_fpsimd_load(struct fpsimd_state *state); +#else +bool kernel_fpsimd_begin(void) +{ + return false; +} + +void kernel_fpsimd_end(void) +{ +} + +/* Functions to use in non-preemptible context */ +void _kernel_fpsimd_save(struct fpsimd_state *state) +{ + (void) state; +} + +void _kernel_fpsimd_load(struct fpsimd_state *state) +{ + (void) state; +} +#endif + #endif /* ! __ASM_NEON_H */ diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h index 9e688b1b13d4..9b81dbcd2126 100644 --- a/arch/arm64/include/asm/processor.h +++ b/arch/arm64/include/asm/processor.h @@ -153,6 +153,10 @@ struct cpu_context { unsigned long pc; }; +struct fpsimd_state { + __uint128_t v[4]; +}; + struct thread_struct { struct cpu_context cpu_context; /* cpu context */ @@ -196,6 +200,12 @@ struct thread_struct { KABI_RESERVE(6) KABI_RESERVE(7) KABI_RESERVE(8) +#ifdef CONFIG_USE_VECTORIZED_COPY + KABI_EXTEND( + struct fpsimd_state ustate; + struct fpsimd_state kstate; + ) +#endif }; static inline unsigned int thread_get_vl(struct thread_struct *thread, diff --git a/arch/arm64/include/asm/thread_info.h b/arch/arm64/include/asm/thread_info.h index 379d24059f5b..60d0be8a2d58 100644 --- a/arch/arm64/include/asm/thread_info.h +++ b/arch/arm64/include/asm/thread_info.h @@ -89,6 +89,9 @@ void arch_setup_new_exec(void); #define TIF_SME 27 /* SME in use */ #define TIF_SME_VL_INHERIT 28 /* Inherit SME vl_onexec across exec */ #define TIF_32BIT_AARCH64 29 /* 32 bit process on AArch64(ILP32) */ +#define TIF_KERNEL_FPSIMD 31 /* Use FPSIMD in kernel */ +#define TIF_PRIV_UACC_ENABLED 32 /* Whether priviliged uaccess was manually enabled */ + #define _TIF_SIGPENDING (1 << TIF_SIGPENDING) #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) @@ -107,6 +110,8 @@ void arch_setup_new_exec(void); #define _TIF_MTE_ASYNC_FAULT (1 << TIF_MTE_ASYNC_FAULT) #define _TIF_NOTIFY_SIGNAL (1 << TIF_NOTIFY_SIGNAL) #define _TIF_32BIT_AARCH64 (1 << TIF_32BIT_AARCH64) +#define _TIF_KERNEL_FPSIMD (1 << TIF_KERNEL_FPSIMD) +#define _TIF_PRIV_UACC_ENABLED (1 << TIF_PRIV_UACC_ENABLED) #define _TIF_WORK_MASK (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \ _TIF_NOTIFY_RESUME | _TIF_FOREIGN_FPSTATE | \ diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h index dd0877a75922..fc9f1a40624d 100644 --- a/arch/arm64/include/asm/uaccess.h +++ b/arch/arm64/include/asm/uaccess.h @@ -26,6 +26,10 @@ #include <asm/memory.h> #include <asm/extable.h> +#ifndef __GENKSYMS__ +#include <asm/neon.h> +#endif + static inline int __access_ok(const void __user *ptr, unsigned long size); /* @@ -134,7 +138,7 @@ static inline void __uaccess_enable_hw_pan(void) CONFIG_ARM64_PAN)); } -static inline void uaccess_disable_privileged(void) +static inline void __uaccess_disable_privileged(void) { mte_disable_tco(); @@ -144,7 +148,22 @@ static inline void uaccess_disable_privileged(void) __uaccess_enable_hw_pan(); } -static inline void uaccess_enable_privileged(void) +static inline void uaccess_disable_privileged(void) +{ + preempt_disable(); + + if (!test_and_clear_thread_flag(TIF_PRIV_UACC_ENABLED)) { + WARN_ON(1); + preempt_enable(); + return; + } + + __uaccess_disable_privileged(); + + preempt_enable(); +} + +static inline void __uaccess_enable_privileged(void) { mte_enable_tco(); @@ -154,6 +173,47 @@ static inline void uaccess_enable_privileged(void) __uaccess_disable_hw_pan(); } +static inline void uaccess_enable_privileged(void) +{ + preempt_disable(); + + if (test_and_set_thread_flag(TIF_PRIV_UACC_ENABLED)) { + WARN_ON(1); + preempt_enable(); + return; + } + + __uaccess_enable_privileged(); + + preempt_enable(); +} + +static inline void uaccess_priviliged_context_switch(struct task_struct *next) +{ + bool curr_enabled = !!test_thread_flag(TIF_PRIV_UACC_ENABLED); + bool next_enabled = !!test_ti_thread_flag(&next->thread_info, TIF_PRIV_UACC_ENABLED); + + if (curr_enabled == next_enabled) + return; + + if (curr_enabled) + __uaccess_disable_privileged(); + else + __uaccess_enable_privileged(); +} + +static inline void uaccess_priviliged_state_save(void) +{ + if (test_thread_flag(TIF_PRIV_UACC_ENABLED)) + __uaccess_disable_privileged(); +} + +static inline void uaccess_priviliged_state_restore(void) +{ + if (test_thread_flag(TIF_PRIV_UACC_ENABLED)) + __uaccess_enable_privileged(); +} + /* * Sanitize a uaccess pointer such that it cannot reach any kernel address. * @@ -391,7 +451,97 @@ do { \ } while (0); \ } while(0) -extern unsigned long __must_check __arch_copy_from_user(void *to, const void __user *from, unsigned long n); +#define USER_COPY_CHUNK_SIZE 4096 + +#ifdef CONFIG_USE_VECTORIZED_COPY + +extern int sysctl_copy_from_user_threshold; + +#define verify_fpsimd_copy(to, from, n, ret) \ +({ \ + unsigned long __verify_ret = 0; \ + __verify_ret = memcmp(to, from, ret ? n - ret : n); \ + if (__verify_ret) \ + pr_err("FPSIMD:%s inconsistent state\n", __func__); \ + if (ret) \ + pr_err("FPSIMD:%s failed to copy data, expected=%lu, copied=%lu\n", __func__, n, n - ret); \ + __verify_ret |= ret; \ + __verify_ret; \ +}) + +#define compare_fpsimd_copy(to, from, n, ret_fpsimd, ret) \ +({ \ + unsigned long __verify_ret = 0; \ + __verify_ret = memcmp(to, from, ret ? n - ret : n); \ + if (__verify_ret) \ + pr_err("FIXUP:%s inconsistent state\n", __func__); \ + if (ret) \ + pr_err("FIXUP:%s failed to copy data, expected=%lu, copied=%lu\n", __func__, n, n - ret); \ + __verify_ret |= ret; \ + if (ret_fpsimd != ret) { \ + pr_err("FIXUP:%s difference between FPSIMD %lu and regular %lu\n", __func__, n - ret_fpsimd, n - ret); \ + __verify_ret |= 1; \ + } else { \ + __verify_ret = 0; \ + } \ + __verify_ret; \ +}) + +extern unsigned long __must_check +__arch_copy_from_user(void *to, const void __user *from, unsigned long n); + +extern unsigned long __must_check +__arch_copy_from_user_fpsimd(void *to, const void __user *from, unsigned long n); + +static __always_inline unsigned long __must_check +raw_copy_from_user(void *to, const void __user *from, unsigned long n) +{ + unsigned long __acfu_ret; + + if (sysctl_copy_from_user_threshold == -1 || n < sysctl_copy_from_user_threshold) { + uaccess_ttbr0_enable(); + __acfu_ret = __arch_copy_from_user(to, + __uaccess_mask_ptr(from), n); + uaccess_ttbr0_disable(); + } else { + if (kernel_fpsimd_begin()) { + unsigned long __acfu_ret_fpsimd; + + uaccess_enable_privileged(); + __acfu_ret_fpsimd = __arch_copy_from_user_fpsimd((to), + __uaccess_mask_ptr(from), n); + uaccess_disable_privileged(); + + __acfu_ret = __acfu_ret_fpsimd; + kernel_fpsimd_end(); +#ifdef CONFIG_VECTORIZED_COPY_VALIDATE + if (verify_fpsimd_copy(to, __uaccess_mask_ptr(from), n, + __acfu_ret)) { + + uaccess_ttbr0_enable(); + __acfu_ret = __arch_copy_from_user((to), + __uaccess_mask_ptr(from), n); + uaccess_ttbr0_disable(); + + compare_fpsimd_copy(to, __uaccess_mask_ptr(from), n, + __acfu_ret_fpsimd, __acfu_ret); + } +#endif + } else { + uaccess_ttbr0_enable(); + __acfu_ret = __arch_copy_from_user((to), + __uaccess_mask_ptr(from), n); + uaccess_ttbr0_disable(); + } + } + + + return __acfu_ret; +} +#else +extern unsigned long __must_check +__arch_copy_from_user(void *to, const void __user *from, unsigned long n); + #define raw_copy_from_user(to, from, n) \ ({ \ unsigned long __acfu_ret; \ @@ -402,7 +552,66 @@ extern unsigned long __must_check __arch_copy_from_user(void *to, const void __u __acfu_ret; \ }) -extern unsigned long __must_check __arch_copy_to_user(void __user *to, const void *from, unsigned long n); +#endif + +#ifdef CONFIG_USE_VECTORIZED_COPY + +extern int sysctl_copy_to_user_threshold; + +extern unsigned long __must_check +__arch_copy_to_user(void __user *to, const void *from, unsigned long n); + +extern unsigned long __must_check +__arch_copy_to_user_fpsimd(void __user *to, const void *from, unsigned long n); + +static __always_inline unsigned long __must_check +raw_copy_to_user(void __user *to, const void *from, unsigned long n) +{ + unsigned long __actu_ret; + + + if (sysctl_copy_to_user_threshold == -1 || n < sysctl_copy_to_user_threshold) { + uaccess_ttbr0_enable(); + __actu_ret = __arch_copy_to_user(__uaccess_mask_ptr(to), + from, n); + uaccess_ttbr0_disable(); + } else { + if (kernel_fpsimd_begin()) { + unsigned long __actu_ret_fpsimd; + + uaccess_enable_privileged(); + __actu_ret_fpsimd = __arch_copy_to_user_fpsimd(__uaccess_mask_ptr(to), + from, n); + uaccess_disable_privileged(); + + kernel_fpsimd_end(); + __actu_ret = __actu_ret_fpsimd; +#ifdef CONFIG_VECTORIZED_COPY_VALIDATE + if (verify_fpsimd_copy(__uaccess_mask_ptr(to), from, n, + __actu_ret)) { + uaccess_ttbr0_enable(); + __actu_ret = __arch_copy_to_user(__uaccess_mask_ptr(to), + from, n); + uaccess_ttbr0_disable(); + + compare_fpsimd_copy(__uaccess_mask_ptr(to), from, n, + __actu_ret_fpsimd, __actu_ret); + } +#endif + } else { + uaccess_ttbr0_enable(); + __actu_ret = __arch_copy_to_user(__uaccess_mask_ptr(to), + from, n); + uaccess_ttbr0_disable(); + } + } + + return __actu_ret; +} +#else +extern unsigned long __must_check +__arch_copy_to_user(void __user *to, const void *from, unsigned long n); + #define raw_copy_to_user(to, from, n) \ ({ \ unsigned long __actu_ret; \ @@ -412,6 +621,7 @@ extern unsigned long __must_check __arch_copy_to_user(void __user *to, const voi uaccess_ttbr0_disable(); \ __actu_ret; \ }) +#endif static __must_check __always_inline bool user_access_begin(const void __user *ptr, size_t len) { diff --git a/arch/arm64/kernel/entry-fpsimd.S b/arch/arm64/kernel/entry-fpsimd.S index 6325db1a2179..6660465f1b7c 100644 --- a/arch/arm64/kernel/entry-fpsimd.S +++ b/arch/arm64/kernel/entry-fpsimd.S @@ -11,6 +11,28 @@ #include <asm/assembler.h> #include <asm/fpsimdmacros.h> +#ifdef CONFIG_USE_VECTORIZED_COPY +/* + * Save the FP registers. + * + * x0 - pointer to struct fpsimd_state_light + */ +SYM_FUNC_START(fpsimd_save_state_light) + fpsimd_save_light x0 + ret +SYM_FUNC_END(fpsimd_save_state_light) + +/* + * Load the FP registers. + * + * x0 - pointer to struct fpsimd_state_light + */ +SYM_FUNC_START(fpsimd_load_state_light) + fpsimd_restore_light x0 + ret +SYM_FUNC_END(fpsimd_load_state_light) +#endif + /* * Save the FP registers. * diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c index 0137d987631e..19fcf3a3ac66 100644 --- a/arch/arm64/kernel/fpsimd.c +++ b/arch/arm64/kernel/fpsimd.c @@ -1577,6 +1577,11 @@ void do_fpsimd_exc(unsigned long esr, struct pt_regs *regs) current); } +#ifdef CONFIG_USE_VECTORIZED_COPY +static void kernel_fpsimd_rollback_changes(void); +static void kernel_fpsimd_restore_changes(struct task_struct *tsk); +#endif + void fpsimd_thread_switch(struct task_struct *next) { bool wrong_task, wrong_cpu; @@ -1585,10 +1590,11 @@ void fpsimd_thread_switch(struct task_struct *next) return; __get_cpu_fpsimd_context(); - +#ifdef CONFIG_USE_VECTORIZED_COPY + kernel_fpsimd_rollback_changes(); +#endif /* Save unsaved fpsimd state, if any: */ fpsimd_save(); - /* * Fix up TIF_FOREIGN_FPSTATE to correctly describe next's * state. For kernel threads, FPSIMD registers are never loaded @@ -1601,6 +1607,9 @@ void fpsimd_thread_switch(struct task_struct *next) update_tsk_thread_flag(next, TIF_FOREIGN_FPSTATE, wrong_task || wrong_cpu); +#ifdef CONFIG_USE_VECTORIZED_COPY + kernel_fpsimd_restore_changes(next); +#endif __put_cpu_fpsimd_context(); } @@ -1956,6 +1965,95 @@ void kernel_neon_end(void) } EXPORT_SYMBOL_GPL(kernel_neon_end); +#ifdef CONFIG_USE_VECTORIZED_COPY +bool kernel_fpsimd_begin(void) +{ + if (WARN_ON(!system_capabilities_finalized()) || + !system_supports_fpsimd() || + in_irq() || irqs_disabled() || in_nmi()) + return false; + + preempt_disable(); + if (test_and_set_thread_flag(TIF_KERNEL_FPSIMD)) { + preempt_enable(); + + WARN_ON(1); + return false; + } + + /* + * Leaving streaming mode enabled will cause issues for any kernel + * NEON and leaving streaming mode or ZA enabled may increase power + * consumption. + */ + if (system_supports_sme()) + sme_smstop(); + + fpsimd_save_state_light(&current->thread.ustate); + preempt_enable(); + + return true; +} +EXPORT_SYMBOL(kernel_fpsimd_begin); + +void kernel_fpsimd_end(void) +{ + if (!system_supports_fpsimd()) + return; + + preempt_disable(); + if (test_and_clear_thread_flag(TIF_KERNEL_FPSIMD)) + fpsimd_load_state_light(&current->thread.ustate); + + preempt_enable(); +} +EXPORT_SYMBOL(kernel_fpsimd_end); + +void _kernel_fpsimd_save(struct fpsimd_state *state) +{ + if (!system_supports_fpsimd()) + return; + + BUG_ON(preemptible()); + if (test_thread_flag(TIF_KERNEL_FPSIMD)) + fpsimd_save_state_light(state); +} + +void _kernel_fpsimd_load(struct fpsimd_state *state) +{ + if (!system_supports_fpsimd()) + return; + + BUG_ON(preemptible()); + if (test_thread_flag(TIF_KERNEL_FPSIMD)) + fpsimd_load_state_light(state); +} + +static void kernel_fpsimd_rollback_changes(void) +{ + if (!system_supports_fpsimd()) + return; + + BUG_ON(preemptible()); + if (test_thread_flag(TIF_KERNEL_FPSIMD)) { + fpsimd_save_state_light(&current->thread.kstate); + fpsimd_load_state_light(&current->thread.ustate); + } +} + +static void kernel_fpsimd_restore_changes(struct task_struct *tsk) +{ + if (!system_supports_fpsimd()) + return; + + BUG_ON(preemptible()); + if (test_ti_thread_flag(task_thread_info(tsk), TIF_KERNEL_FPSIMD)) { + fpsimd_save_state_light(&tsk->thread.ustate); + fpsimd_load_state_light(&tsk->thread.kstate); + } +} +#endif + #ifdef CONFIG_EFI static DEFINE_PER_CPU(struct user_fpsimd_state, efi_fpsimd_state); diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c index 068e5bb2661b..bbeb36e671de 100644 --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -524,7 +524,7 @@ struct task_struct *__switch_to(struct task_struct *prev, struct task_struct *next) { struct task_struct *last; - + uaccess_priviliged_context_switch(next); fpsimd_thread_switch(next); tls_thread_switch(next); hw_breakpoint_thread_switch(next); diff --git a/arch/arm64/lib/copy_from_user.S b/arch/arm64/lib/copy_from_user.S index 34e317907524..60dc63e10233 100644 --- a/arch/arm64/lib/copy_from_user.S +++ b/arch/arm64/lib/copy_from_user.S @@ -71,3 +71,33 @@ USER(9998f, ldtrb tmp1w, [srcin]) ret SYM_FUNC_END(__arch_copy_from_user) EXPORT_SYMBOL(__arch_copy_from_user) + + + +#ifdef CONFIG_USE_VECTORIZED_COPY + .macro ldsve reg1, reg2, reg3, reg4, ptr + USER(9997f, ld1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + + .macro stsve reg1, reg2, reg3, reg4, ptr + KERNEL_ME_SAFE(9998f, st1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + +SYM_FUNC_START(__arch_copy_from_user_fpsimd) + add end, x0, x2 + mov srcin, x1 +#include "copy_template_fpsimd.S" + mov x0, #0 // Nothing to copy + ret + + // Exception fixups +9997: cmp dst, dstin + b.ne 9998f + // Before being absolutely sure we couldn't copy anything, try harder +USER(9998f, ldtrb tmp1w, [srcin]) + strb tmp1w, [dst], #1 +9998: sub x0, end, dst // bytes not copied + ret +SYM_FUNC_END(__arch_copy_from_user_fpsimd) +EXPORT_SYMBOL(__arch_copy_from_user_fpsimd) +#endif \ No newline at end of file diff --git a/arch/arm64/lib/copy_template_fpsimd.S b/arch/arm64/lib/copy_template_fpsimd.S new file mode 100644 index 000000000000..9b2e7ce1e4d2 --- /dev/null +++ b/arch/arm64/lib/copy_template_fpsimd.S @@ -0,0 +1,180 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2013 ARM Ltd. + * Copyright (C) 2013 Linaro. + * + * This code is based on glibc cortex strings work originally authored by Linaro + * be found @ + * + * http://bazaar.launchpad.net/~linaro-toolchain-dev/cortex-strings/trunk/ + * files/head:/src/aarch64/ + */ + +/* + * Copy a buffer from src to dest (alignment handled by the hardware) + * + * Parameters: + * x0 - dest + * x1 - src + * x2 - n + * Returns: + * x0 - dest + */ +dstin .req x0 +src .req x1 +count .req x2 +tmp1 .req x3 +tmp1w .req w3 +tmp2 .req x4 +tmp2w .req w4 +dst .req x6 + +A_l .req x7 +A_h .req x8 +B_l .req x9 +B_h .req x10 +C_l .req x11 +C_h .req x12 +D_l .req x13 +D_h .req x14 + +V_a .req v20 +V_b .req v21 +V_c .req v22 +V_d .req v23 + + mov dst, dstin + cmp count, #16 + /*When memory length is less than 16, the accessed are not aligned.*/ + b.lo .Ltiny15_fpsimd + + neg tmp2, src + ands tmp2, tmp2, #15/* Bytes to reach alignment. */ + b.eq .LSrcAligned_fpsimd + sub count, count, tmp2 + /* + * Copy the leading memory data from src to dst in an increasing + * address order.By this way,the risk of overwriting the source + * memory data is eliminated when the distance between src and + * dst is less than 16. The memory accesses here are alignment. + */ + tbz tmp2, #0, 1f + ldrb1 tmp1w, src, #1 + strb1 tmp1w, dst, #1 +1: + tbz tmp2, #1, 2f + ldrh1 tmp1w, src, #2 + strh1 tmp1w, dst, #2 +2: + tbz tmp2, #2, 3f + ldr1 tmp1w, src, #4 + str1 tmp1w, dst, #4 +3: + tbz tmp2, #3, .LSrcAligned_fpsimd + ldr1 tmp1, src, #8 + str1 tmp1, dst, #8 + +.LSrcAligned_fpsimd: + cmp count, #64 + b.ge .Lcpy_over64_fpsimd + /* + * Deal with small copies quickly by dropping straight into the + * exit block. + */ +.Ltail63_fpsimd: + /* + * Copy up to 48 bytes of data. At this point we only need the + * bottom 6 bits of count to be accurate. + */ + ands tmp1, count, #0x30 + b.eq .Ltiny15_fpsimd + cmp tmp1w, #0x20 + b.eq 1f + b.lt 2f + ldp1 A_l, A_h, src, #16 + stp1 A_l, A_h, dst, #16 +1: + ldp1 A_l, A_h, src, #16 + stp1 A_l, A_h, dst, #16 +2: + ldp1 A_l, A_h, src, #16 + stp1 A_l, A_h, dst, #16 +.Ltiny15_fpsimd: + /* + * Prefer to break one ldp/stp into several load/store to access + * memory in an increasing address order,rather than to load/store 16 + * bytes from (src-16) to (dst-16) and to backward the src to aligned + * address,which way is used in original cortex memcpy. If keeping + * the original memcpy process here, memmove need to satisfy the + * precondition that src address is at least 16 bytes bigger than dst + * address,otherwise some source data will be overwritten when memove + * call memcpy directly. To make memmove simpler and decouple the + * memcpy's dependency on memmove, withdrew the original process. + */ + tbz count, #3, 1f + ldr1 tmp1, src, #8 + str1 tmp1, dst, #8 +1: + tbz count, #2, 2f + ldr1 tmp1w, src, #4 + str1 tmp1w, dst, #4 +2: + tbz count, #1, 3f + ldrh1 tmp1w, src, #2 + strh1 tmp1w, dst, #2 +3: + tbz count, #0, .Lexitfunc_fpsimd + ldrb1 tmp1w, src, #1 + strb1 tmp1w, dst, #1 + + b .Lexitfunc_fpsimd + +.Lcpy_over64_fpsimd: + subs count, count, #128 + b.ge .Lcpy_body_large_fpsimd + /* + * Less than 128 bytes to copy, so handle 64 here and then jump + * to the tail. + */ + ldp1 A_l, A_h, src, #16 + stp1 A_l, A_h, dst, #16 + ldp1 B_l, B_h, src, #16 + ldp1 C_l, C_h, src, #16 + stp1 B_l, B_h, dst, #16 + stp1 C_l, C_h, dst, #16 + ldp1 D_l, D_h, src, #16 + stp1 D_l, D_h, dst, #16 + + tst count, #0x3f + b.ne .Ltail63_fpsimd + b .Lexitfunc_fpsimd + + /* + * Critical loop. Start at a new cache line boundary. Assuming + * 64 bytes per line this ensures the entire loop is in one line. + */ + .p2align L1_CACHE_SHIFT +.Lcpy_body_large_fpsimd: + /* pre-get 64 bytes data. */ + ldsve V_a.16b, V_b.16b, V_c.16b, V_d.16b, src + add src, src, #64 + +1: + /* + * interlace the load of next 64 bytes data block with store of the last + * loaded 64 bytes data. + */ + stsve V_a.16b, V_b.16b, V_c.16b, V_d.16b, dst + ldsve V_a.16b, V_b.16b, V_c.16b, V_d.16b, src + add dst, dst, #64 + add src, src, #64 + + subs count, count, #64 + b.ge 1b + + stsve V_a.16b, V_b.16b, V_c.16b, V_d.16b, dst + add dst, dst, #64 + + tst count, #0x3f + b.ne .Ltail63_fpsimd +.Lexitfunc_fpsimd: diff --git a/arch/arm64/lib/copy_to_user.S b/arch/arm64/lib/copy_to_user.S index 2ac716c0d6d8..c190e5f8a989 100644 --- a/arch/arm64/lib/copy_to_user.S +++ b/arch/arm64/lib/copy_to_user.S @@ -71,3 +71,33 @@ USER(9998f, sttrb tmp1w, [dst]) ret SYM_FUNC_END(__arch_copy_to_user) EXPORT_SYMBOL(__arch_copy_to_user) + + +#ifdef CONFIG_USE_VECTORIZED_COPY + .macro stsve reg1, reg2, reg3, reg4, ptr + USER(9997f, st1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + + .macro ldsve reg1, reg2, reg3, reg4, ptr + KERNEL_ME_SAFE(9998f, ld1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + +SYM_FUNC_START(__arch_copy_to_user_fpsimd) + add end, x0, x2 + mov srcin, x1 +#include "copy_template_fpsimd.S" + mov x0, #0 + ret + + // Exception fixups +9997: cmp dst, dstin + b.ne 9998f + // Before being absolutely sure we couldn't copy anything, try harder +KERNEL_ME_SAFE(9998f, ldrb tmp1w, [srcin]) +USER(9998f, sttrb tmp1w, [dst]) + add dst, dst, #1 +9998: sub x0, end, dst // bytes not copied + ret +SYM_FUNC_END(__arch_copy_to_user_fpsimd) +EXPORT_SYMBOL(__arch_copy_to_user_fpsimd) +#endif diff --git a/kernel/softirq.c b/kernel/softirq.c index cd8770b2f76c..e8ce3275a099 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -30,6 +30,10 @@ #include <asm/softirq_stack.h> +#ifdef CONFIG_USE_VECTORIZED_COPY +#include <asm/fpsimd.h> +#endif + #define CREATE_TRACE_POINTS #include <trace/events/irq.h> @@ -517,6 +521,9 @@ static void handle_softirqs(bool ksirqd) __u32 pending; int softirq_bit; +#ifdef CONFIG_USE_VECTORIZED_COPY + struct fpsimd_state state; +#endif /* * Mask out PF_MEMALLOC as the current task context is borrowed for the * softirq. A softirq handled, such as network RX, might set PF_MEMALLOC @@ -526,10 +533,16 @@ static void handle_softirqs(bool ksirqd) pending = local_softirq_pending(); + softirq_handle_begin(); in_hardirq = lockdep_softirq_start(); account_softirq_enter(current); +#ifdef CONFIG_USE_VECTORIZED_COPY + _kernel_fpsimd_save(&state); + uaccess_priviliged_state_save(); +#endif + restart: /* Reset the pending bitmask before enabling irqs */ set_softirq_pending(0); @@ -578,7 +591,14 @@ static void handle_softirqs(bool ksirqd) account_softirq_exit(current); lockdep_softirq_end(in_hardirq); + +#ifdef CONFIG_USE_VECTORIZED_COPY + uaccess_priviliged_state_restore(); + _kernel_fpsimd_load(&state); +#endif + softirq_handle_end(); + current_restore_flags(old_flags, PF_MEMALLOC); } @@ -812,12 +832,21 @@ static void tasklet_action_common(struct softirq_action *a, { struct tasklet_struct *list; +#ifdef CONFIG_USE_VECTORIZED_COPY + struct fpsimd_state state; +#endif + local_irq_disable(); list = tl_head->head; tl_head->head = NULL; tl_head->tail = &tl_head->head; local_irq_enable(); +#ifdef CONFIG_USE_VECTORIZED_COPY + _kernel_fpsimd_save(&state); + uaccess_priviliged_state_save(); +#endif + while (list) { struct tasklet_struct *t = list; @@ -849,6 +878,11 @@ static void tasklet_action_common(struct softirq_action *a, __raise_softirq_irqoff(softirq_nr); local_irq_enable(); } + +#ifdef CONFIG_USE_VECTORIZED_COPY + uaccess_priviliged_state_restore(); + _kernel_fpsimd_load(&state); +#endif } static __latent_entropy void tasklet_action(struct softirq_action *a) diff --git a/kernel/sysctl.c b/kernel/sysctl.c index e84df0818517..6f8e22102bdc 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -137,6 +137,17 @@ int sysctl_legacy_va_layout; #endif /* CONFIG_SYSCTL */ +#ifdef CONFIG_USE_VECTORIZED_COPY +int sysctl_copy_to_user_threshold = -1; +EXPORT_SYMBOL(sysctl_copy_to_user_threshold); + +int sysctl_copy_from_user_threshold = -1; +EXPORT_SYMBOL(sysctl_copy_from_user_threshold); + +int sysctl_copy_in_user_threshold = -1; +EXPORT_SYMBOL(sysctl_copy_in_user_threshold); +#endif + /* * /proc/sys support */ @@ -2250,6 +2261,29 @@ static struct ctl_table vm_table[] = { .extra1 = (void *)&mmap_rnd_compat_bits_min, .extra2 = (void *)&mmap_rnd_compat_bits_max, }, +#endif +#ifdef CONFIG_USE_VECTORIZED_COPY + { + .procname = "copy_to_user_threshold", + .data = &sysctl_copy_to_user_threshold, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec + }, + { + .procname = "copy_from_user_threshold", + .data = &sysctl_copy_from_user_threshold, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec + }, + { + .procname = "copy_in_user_threshold", + .data = &sysctl_copy_in_user_threshold, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec + }, #endif { } }; -- 2.34.1

2 1

[PATCH v1 OLK-6.6] Add copy to/from/in user with vectorization support
by Nikita Panov 28 Jan '26

28 Jan '26

From: Artem Kuzin <artem.kuzin(a)huawei.com> kunpeng inclusion category: feature bugzilla: https://atomgit.com/openeuler/kernel/issues/8445 ------------------------------------------------- 1. This implementation uses st1/ld1 4-vector instructions which allow to copy 64 bytes at once 2. Copy code is used only if size of data block to copy is more than 128 bytes 4. To use this functionality you need to set configuration switch CONFIG_USE_VECTORIZED_COPY=y 5. Code can be used on any ARMv8 variant 6. In kernel copy functions like memcpy are not supported now, but can be enabled in future 7. For now we use lightweght version of register context saving/restoration (4-registers) We introduce support of vectorization for copy_from/to/in_user functions. Nowadays it works in parallel with original FPSIMD/SVE vectorization and doesn't affect it anyhow. We have special flag in task struct - TIF_KERNEL_FPSIMD, that set if currently we use lightweight vectorization in kernel. Task struct has been updated by two fields: user space fpsimd state and kernel fpsimd state. User space fpsimd state used by kernel_fpsimd_begin(), kernel_fpsimd_end() functions that wrap lightweight FPSIMD contexts usage in kernel space. Kernel fpsimd state is used to manage threads switch. Now there is no support of nested calls of kernel_neon_begin()/kernel_fpsimd_begin() and there is no plans to support this in future. This is not necessary. We save lightweight FPSIMD context in kernel_fpsimd_begin(), and restore it in /kernel_fpsimd_end(). On thread switch we preserve kernel FPSIMD context and restore user space one if any. This prevens curruption of user space FPSIMD state. Before switching to the next thread we restore it's kernel FPSIMD context if any. It is allowed to use FPSIMD in bottom halves, due to in case of BH preemption we check TIF_KERNEL_FPSIMD flag and save/restore contexts. Context management if quite lightweight and executed only in case of TIF_KERNEL_FPSIMD flag is set. To enable this feature, you need to manually modify one of the appropriate entries: /proc/sys/vm/copy_from_user_threshold /proc/sys/vm/copy_in_user_threshold /proc/sys/vm/copy_to_user_threshold Allowed values are following: -1 - feature enabled 0 - feature always enabled n (n >0) - feature enabled, if copied size is greater than n KB. P.S.: What I am personally don't like in current approach: 1. Additional fields and flag in task struct look quite ugly 2. No way to configure the size of chunk to copy using FPSIMD from user space 3. FPSIMD-based memory movement is not generic, need to enable for memmove(), memcpy() and friends in future. Co-developed-by: Alexander Kozhevnikov <alexander.kozhevnikov(a)huawei-partners.com> Signed-off-by: Alexander Kozhevnikov <alexander.kozhevnikov(a)huawei-partners.com> Co-developed-by: Nikita Panov <panov.nikita(a)huawei.com> Signed-off-by: Nikita Panov <panov.nikita(a)huawei.com> Signed-off-by: Artem Kuzin <artem.kuzin(a)huawei.com> --- arch/arm64/Kconfig | 15 ++ arch/arm64/configs/openeuler_defconfig | 2 + arch/arm64/include/asm/fpsimd.h | 15 ++ arch/arm64/include/asm/fpsimdmacros.h | 14 ++ arch/arm64/include/asm/neon.h | 28 ++++ arch/arm64/include/asm/processor.h | 10 ++ arch/arm64/include/asm/thread_info.h | 5 + arch/arm64/include/asm/uaccess.h | 218 ++++++++++++++++++++++++- arch/arm64/kernel/entry-fpsimd.S | 22 +++ arch/arm64/kernel/fpsimd.c | 102 +++++++++++- arch/arm64/kernel/process.c | 2 +- arch/arm64/lib/copy_from_user.S | 30 ++++ arch/arm64/lib/copy_template_fpsimd.S | 180 ++++++++++++++++++++ arch/arm64/lib/copy_to_user.S | 30 ++++ kernel/softirq.c | 34 ++++ kernel/sysctl.c | 34 ++++ 16 files changed, 734 insertions(+), 7 deletions(-) create mode 100644 arch/arm64/lib/copy_template_fpsimd.S diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index ef8c524a296d..15ec2232994a 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -1870,6 +1870,21 @@ config ARM64_ILP32 is an ABI where long and pointers are 32bits but it uses the AARCH64 instruction set. +config USE_VECTORIZED_COPY + bool "Use vectorized instructions in copy_to/from user" + depends on KERNEL_MODE_NEON + default y + help + This option turns on vectorization to speed up copy_to/from_user routines. + +config VECTORIZED_COPY_VALIDATE + bool "Validate result of vectorized copy using regular implementation" + depends on KERNEL_MODE_NEON + depends on USE_VECTORIZED_COPY + default n + help + This option turns on vectorization to speed up copy_to/from_user routines. + menuconfig AARCH32_EL0 bool "Kernel support for 32-bit EL0" depends on ARM64_4K_PAGES || EXPERT diff --git a/arch/arm64/configs/openeuler_defconfig b/arch/arm64/configs/openeuler_defconfig index 425616aa8422..331077d556ca 100644 --- a/arch/arm64/configs/openeuler_defconfig +++ b/arch/arm64/configs/openeuler_defconfig @@ -525,6 +525,8 @@ CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY=y # CONFIG_RODATA_FULL_DEFAULT_ENABLED is not set # CONFIG_ARM64_SW_TTBR0_PAN is not set CONFIG_ARM64_TAGGED_ADDR_ABI=y +CONFIG_USE_VECTORIZED_COPY=y +# CONFIG_VECTORIZED_COPY_VALIDATE is not set CONFIG_AARCH32_EL0=y # CONFIG_KUSER_HELPERS is not set # CONFIG_COMPAT_ALIGNMENT_FIXUPS is not set diff --git a/arch/arm64/include/asm/fpsimd.h b/arch/arm64/include/asm/fpsimd.h index b6c6949984d8..1fc9089b4a47 100644 --- a/arch/arm64/include/asm/fpsimd.h +++ b/arch/arm64/include/asm/fpsimd.h @@ -46,6 +46,21 @@ struct task_struct; +#ifdef CONFIG_USE_VECTORIZED_COPY +extern void fpsimd_save_state_light(struct fpsimd_state *state); +extern void fpsimd_load_state_light(struct fpsimd_state *state); +#else +static inline void fpsimd_save_state_light(struct fpsimd_state *state) +{ + (void) state; +} + +static inline void fpsimd_load_state_light(struct fpsimd_state *state) +{ + (void) state; +} +#endif + extern void fpsimd_save_state(struct user_fpsimd_state *state); extern void fpsimd_load_state(struct user_fpsimd_state *state); diff --git a/arch/arm64/include/asm/fpsimdmacros.h b/arch/arm64/include/asm/fpsimdmacros.h index cdf6a35e3994..df9d3ed91931 100644 --- a/arch/arm64/include/asm/fpsimdmacros.h +++ b/arch/arm64/include/asm/fpsimdmacros.h @@ -8,6 +8,20 @@ #include <asm/assembler.h> +#ifdef CONFIG_USE_VECTORIZED_COPY +/* Lightweight fpsimd context saving/restoration. + * Necessary for vectorized kernel memory movement + * implementation + */ +.macro fpsimd_save_light state + st1 {v20.16b, v21.16b, v22.16b, v23.16b}, [\state] +.endm + +.macro fpsimd_restore_light state + ld1 {v20.16b, v21.16b, v22.16b, v23.16b}, [\state] +.endm +#endif + .macro fpsimd_save state, tmpnr stp q0, q1, [\state, #16 * 0] stp q2, q3, [\state, #16 * 2] diff --git a/arch/arm64/include/asm/neon.h b/arch/arm64/include/asm/neon.h index d4b1d172a79b..ab84b194d7b3 100644 --- a/arch/arm64/include/asm/neon.h +++ b/arch/arm64/include/asm/neon.h @@ -16,4 +16,32 @@ void kernel_neon_begin(void); void kernel_neon_end(void); +#ifdef CONFIG_USE_VECTORIZED_COPY +bool kernel_fpsimd_begin(void); +void kernel_fpsimd_end(void); +/* Functions to use in non-preemptible context */ +void _kernel_fpsimd_save(struct fpsimd_state *state); +void _kernel_fpsimd_load(struct fpsimd_state *state); +#else +bool kernel_fpsimd_begin(void) +{ + return false; +} + +void kernel_fpsimd_end(void) +{ +} + +/* Functions to use in non-preemptible context */ +void _kernel_fpsimd_save(struct fpsimd_state *state) +{ + (void) state; +} + +void _kernel_fpsimd_load(struct fpsimd_state *state) +{ + (void) state; +} +#endif + #endif /* ! __ASM_NEON_H */ diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h index 9e688b1b13d4..9b81dbcd2126 100644 --- a/arch/arm64/include/asm/processor.h +++ b/arch/arm64/include/asm/processor.h @@ -153,6 +153,10 @@ struct cpu_context { unsigned long pc; }; +struct fpsimd_state { + __uint128_t v[4]; +}; + struct thread_struct { struct cpu_context cpu_context; /* cpu context */ @@ -196,6 +200,12 @@ struct thread_struct { KABI_RESERVE(6) KABI_RESERVE(7) KABI_RESERVE(8) +#ifdef CONFIG_USE_VECTORIZED_COPY + KABI_EXTEND( + struct fpsimd_state ustate; + struct fpsimd_state kstate; + ) +#endif }; static inline unsigned int thread_get_vl(struct thread_struct *thread, diff --git a/arch/arm64/include/asm/thread_info.h b/arch/arm64/include/asm/thread_info.h index 379d24059f5b..60d0be8a2d58 100644 --- a/arch/arm64/include/asm/thread_info.h +++ b/arch/arm64/include/asm/thread_info.h @@ -89,6 +89,9 @@ void arch_setup_new_exec(void); #define TIF_SME 27 /* SME in use */ #define TIF_SME_VL_INHERIT 28 /* Inherit SME vl_onexec across exec */ #define TIF_32BIT_AARCH64 29 /* 32 bit process on AArch64(ILP32) */ +#define TIF_KERNEL_FPSIMD 31 /* Use FPSIMD in kernel */ +#define TIF_PRIV_UACC_ENABLED 32 /* Whether priviliged uaccess was manually enabled */ + #define _TIF_SIGPENDING (1 << TIF_SIGPENDING) #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) @@ -107,6 +110,8 @@ void arch_setup_new_exec(void); #define _TIF_MTE_ASYNC_FAULT (1 << TIF_MTE_ASYNC_FAULT) #define _TIF_NOTIFY_SIGNAL (1 << TIF_NOTIFY_SIGNAL) #define _TIF_32BIT_AARCH64 (1 << TIF_32BIT_AARCH64) +#define _TIF_KERNEL_FPSIMD (1 << TIF_KERNEL_FPSIMD) +#define _TIF_PRIV_UACC_ENABLED (1 << TIF_PRIV_UACC_ENABLED) #define _TIF_WORK_MASK (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \ _TIF_NOTIFY_RESUME | _TIF_FOREIGN_FPSTATE | \ diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h index dd0877a75922..fc9f1a40624d 100644 --- a/arch/arm64/include/asm/uaccess.h +++ b/arch/arm64/include/asm/uaccess.h @@ -26,6 +26,10 @@ #include <asm/memory.h> #include <asm/extable.h> +#ifndef __GENKSYMS__ +#include <asm/neon.h> +#endif + static inline int __access_ok(const void __user *ptr, unsigned long size); /* @@ -134,7 +138,7 @@ static inline void __uaccess_enable_hw_pan(void) CONFIG_ARM64_PAN)); } -static inline void uaccess_disable_privileged(void) +static inline void __uaccess_disable_privileged(void) { mte_disable_tco(); @@ -144,7 +148,22 @@ static inline void uaccess_disable_privileged(void) __uaccess_enable_hw_pan(); } -static inline void uaccess_enable_privileged(void) +static inline void uaccess_disable_privileged(void) +{ + preempt_disable(); + + if (!test_and_clear_thread_flag(TIF_PRIV_UACC_ENABLED)) { + WARN_ON(1); + preempt_enable(); + return; + } + + __uaccess_disable_privileged(); + + preempt_enable(); +} + +static inline void __uaccess_enable_privileged(void) { mte_enable_tco(); @@ -154,6 +173,47 @@ static inline void uaccess_enable_privileged(void) __uaccess_disable_hw_pan(); } +static inline void uaccess_enable_privileged(void) +{ + preempt_disable(); + + if (test_and_set_thread_flag(TIF_PRIV_UACC_ENABLED)) { + WARN_ON(1); + preempt_enable(); + return; + } + + __uaccess_enable_privileged(); + + preempt_enable(); +} + +static inline void uaccess_priviliged_context_switch(struct task_struct *next) +{ + bool curr_enabled = !!test_thread_flag(TIF_PRIV_UACC_ENABLED); + bool next_enabled = !!test_ti_thread_flag(&next->thread_info, TIF_PRIV_UACC_ENABLED); + + if (curr_enabled == next_enabled) + return; + + if (curr_enabled) + __uaccess_disable_privileged(); + else + __uaccess_enable_privileged(); +} + +static inline void uaccess_priviliged_state_save(void) +{ + if (test_thread_flag(TIF_PRIV_UACC_ENABLED)) + __uaccess_disable_privileged(); +} + +static inline void uaccess_priviliged_state_restore(void) +{ + if (test_thread_flag(TIF_PRIV_UACC_ENABLED)) + __uaccess_enable_privileged(); +} + /* * Sanitize a uaccess pointer such that it cannot reach any kernel address. * @@ -391,7 +451,97 @@ do { \ } while (0); \ } while(0) -extern unsigned long __must_check __arch_copy_from_user(void *to, const void __user *from, unsigned long n); +#define USER_COPY_CHUNK_SIZE 4096 + +#ifdef CONFIG_USE_VECTORIZED_COPY + +extern int sysctl_copy_from_user_threshold; + +#define verify_fpsimd_copy(to, from, n, ret) \ +({ \ + unsigned long __verify_ret = 0; \ + __verify_ret = memcmp(to, from, ret ? n - ret : n); \ + if (__verify_ret) \ + pr_err("FPSIMD:%s inconsistent state\n", __func__); \ + if (ret) \ + pr_err("FPSIMD:%s failed to copy data, expected=%lu, copied=%lu\n", __func__, n, n - ret); \ + __verify_ret |= ret; \ + __verify_ret; \ +}) + +#define compare_fpsimd_copy(to, from, n, ret_fpsimd, ret) \ +({ \ + unsigned long __verify_ret = 0; \ + __verify_ret = memcmp(to, from, ret ? n - ret : n); \ + if (__verify_ret) \ + pr_err("FIXUP:%s inconsistent state\n", __func__); \ + if (ret) \ + pr_err("FIXUP:%s failed to copy data, expected=%lu, copied=%lu\n", __func__, n, n - ret); \ + __verify_ret |= ret; \ + if (ret_fpsimd != ret) { \ + pr_err("FIXUP:%s difference between FPSIMD %lu and regular %lu\n", __func__, n - ret_fpsimd, n - ret); \ + __verify_ret |= 1; \ + } else { \ + __verify_ret = 0; \ + } \ + __verify_ret; \ +}) + +extern unsigned long __must_check +__arch_copy_from_user(void *to, const void __user *from, unsigned long n); + +extern unsigned long __must_check +__arch_copy_from_user_fpsimd(void *to, const void __user *from, unsigned long n); + +static __always_inline unsigned long __must_check +raw_copy_from_user(void *to, const void __user *from, unsigned long n) +{ + unsigned long __acfu_ret; + + if (sysctl_copy_from_user_threshold == -1 || n < sysctl_copy_from_user_threshold) { + uaccess_ttbr0_enable(); + __acfu_ret = __arch_copy_from_user(to, + __uaccess_mask_ptr(from), n); + uaccess_ttbr0_disable(); + } else { + if (kernel_fpsimd_begin()) { + unsigned long __acfu_ret_fpsimd; + + uaccess_enable_privileged(); + __acfu_ret_fpsimd = __arch_copy_from_user_fpsimd((to), + __uaccess_mask_ptr(from), n); + uaccess_disable_privileged(); + + __acfu_ret = __acfu_ret_fpsimd; + kernel_fpsimd_end(); +#ifdef CONFIG_VECTORIZED_COPY_VALIDATE + if (verify_fpsimd_copy(to, __uaccess_mask_ptr(from), n, + __acfu_ret)) { + + uaccess_ttbr0_enable(); + __acfu_ret = __arch_copy_from_user((to), + __uaccess_mask_ptr(from), n); + uaccess_ttbr0_disable(); + + compare_fpsimd_copy(to, __uaccess_mask_ptr(from), n, + __acfu_ret_fpsimd, __acfu_ret); + } +#endif + } else { + uaccess_ttbr0_enable(); + __acfu_ret = __arch_copy_from_user((to), + __uaccess_mask_ptr(from), n); + uaccess_ttbr0_disable(); + } + } + + + return __acfu_ret; +} +#else +extern unsigned long __must_check +__arch_copy_from_user(void *to, const void __user *from, unsigned long n); + #define raw_copy_from_user(to, from, n) \ ({ \ unsigned long __acfu_ret; \ @@ -402,7 +552,66 @@ extern unsigned long __must_check __arch_copy_from_user(void *to, const void __u __acfu_ret; \ }) -extern unsigned long __must_check __arch_copy_to_user(void __user *to, const void *from, unsigned long n); +#endif + +#ifdef CONFIG_USE_VECTORIZED_COPY + +extern int sysctl_copy_to_user_threshold; + +extern unsigned long __must_check +__arch_copy_to_user(void __user *to, const void *from, unsigned long n); + +extern unsigned long __must_check +__arch_copy_to_user_fpsimd(void __user *to, const void *from, unsigned long n); + +static __always_inline unsigned long __must_check +raw_copy_to_user(void __user *to, const void *from, unsigned long n) +{ + unsigned long __actu_ret; + + + if (sysctl_copy_to_user_threshold == -1 || n < sysctl_copy_to_user_threshold) { + uaccess_ttbr0_enable(); + __actu_ret = __arch_copy_to_user(__uaccess_mask_ptr(to), + from, n); + uaccess_ttbr0_disable(); + } else { + if (kernel_fpsimd_begin()) { + unsigned long __actu_ret_fpsimd; + + uaccess_enable_privileged(); + __actu_ret_fpsimd = __arch_copy_to_user_fpsimd(__uaccess_mask_ptr(to), + from, n); + uaccess_disable_privileged(); + + kernel_fpsimd_end(); + __actu_ret = __actu_ret_fpsimd; +#ifdef CONFIG_VECTORIZED_COPY_VALIDATE + if (verify_fpsimd_copy(__uaccess_mask_ptr(to), from, n, + __actu_ret)) { + uaccess_ttbr0_enable(); + __actu_ret = __arch_copy_to_user(__uaccess_mask_ptr(to), + from, n); + uaccess_ttbr0_disable(); + + compare_fpsimd_copy(__uaccess_mask_ptr(to), from, n, + __actu_ret_fpsimd, __actu_ret); + } +#endif + } else { + uaccess_ttbr0_enable(); + __actu_ret = __arch_copy_to_user(__uaccess_mask_ptr(to), + from, n); + uaccess_ttbr0_disable(); + } + } + + return __actu_ret; +} +#else +extern unsigned long __must_check +__arch_copy_to_user(void __user *to, const void *from, unsigned long n); + #define raw_copy_to_user(to, from, n) \ ({ \ unsigned long __actu_ret; \ @@ -412,6 +621,7 @@ extern unsigned long __must_check __arch_copy_to_user(void __user *to, const voi uaccess_ttbr0_disable(); \ __actu_ret; \ }) +#endif static __must_check __always_inline bool user_access_begin(const void __user *ptr, size_t len) { diff --git a/arch/arm64/kernel/entry-fpsimd.S b/arch/arm64/kernel/entry-fpsimd.S index 6325db1a2179..6660465f1b7c 100644 --- a/arch/arm64/kernel/entry-fpsimd.S +++ b/arch/arm64/kernel/entry-fpsimd.S @@ -11,6 +11,28 @@ #include <asm/assembler.h> #include <asm/fpsimdmacros.h> +#ifdef CONFIG_USE_VECTORIZED_COPY +/* + * Save the FP registers. + * + * x0 - pointer to struct fpsimd_state_light + */ +SYM_FUNC_START(fpsimd_save_state_light) + fpsimd_save_light x0 + ret +SYM_FUNC_END(fpsimd_save_state_light) + +/* + * Load the FP registers. + * + * x0 - pointer to struct fpsimd_state_light + */ +SYM_FUNC_START(fpsimd_load_state_light) + fpsimd_restore_light x0 + ret +SYM_FUNC_END(fpsimd_load_state_light) +#endif + /* * Save the FP registers. * diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c index b86a50646700..103559cccb07 100644 --- a/arch/arm64/kernel/fpsimd.c +++ b/arch/arm64/kernel/fpsimd.c @@ -1579,6 +1579,11 @@ void do_fpsimd_exc(unsigned long esr, struct pt_regs *regs) current); } +#ifdef CONFIG_USE_VECTORIZED_COPY +static void kernel_fpsimd_rollback_changes(void); +static void kernel_fpsimd_restore_changes(struct task_struct *tsk); +#endif + void fpsimd_thread_switch(struct task_struct *next) { bool wrong_task, wrong_cpu; @@ -1587,10 +1592,11 @@ void fpsimd_thread_switch(struct task_struct *next) return; __get_cpu_fpsimd_context(); - +#ifdef CONFIG_USE_VECTORIZED_COPY + kernel_fpsimd_rollback_changes(); +#endif /* Save unsaved fpsimd state, if any: */ fpsimd_save(); - /* * Fix up TIF_FOREIGN_FPSTATE to correctly describe next's * state. For kernel threads, FPSIMD registers are never loaded @@ -1603,6 +1609,9 @@ void fpsimd_thread_switch(struct task_struct *next) update_tsk_thread_flag(next, TIF_FOREIGN_FPSTATE, wrong_task || wrong_cpu); +#ifdef CONFIG_USE_VECTORIZED_COPY + kernel_fpsimd_restore_changes(next); +#endif __put_cpu_fpsimd_context(); } @@ -1933,6 +1942,95 @@ void kernel_neon_end(void) } EXPORT_SYMBOL_GPL(kernel_neon_end); +#ifdef CONFIG_USE_VECTORIZED_COPY +bool kernel_fpsimd_begin(void) +{ + if (WARN_ON(!system_capabilities_finalized()) || + !system_supports_fpsimd() || + in_irq() || irqs_disabled() || in_nmi()) + return false; + + preempt_disable(); + if (test_and_set_thread_flag(TIF_KERNEL_FPSIMD)) { + preempt_enable(); + + WARN_ON(1); + return false; + } + + /* + * Leaving streaming mode enabled will cause issues for any kernel + * NEON and leaving streaming mode or ZA enabled may increase power + * consumption. + */ + if (system_supports_sme()) + sme_smstop(); + + fpsimd_save_state_light(&current->thread.ustate); + preempt_enable(); + + return true; +} +EXPORT_SYMBOL(kernel_fpsimd_begin); + +void kernel_fpsimd_end(void) +{ + if (!system_supports_fpsimd()) + return; + + preempt_disable(); + if (test_and_clear_thread_flag(TIF_KERNEL_FPSIMD)) + fpsimd_load_state_light(&current->thread.ustate); + + preempt_enable(); +} +EXPORT_SYMBOL(kernel_fpsimd_end); + +void _kernel_fpsimd_save(struct fpsimd_state *state) +{ + if (!system_supports_fpsimd()) + return; + + BUG_ON(preemptible()); + if (test_thread_flag(TIF_KERNEL_FPSIMD)) + fpsimd_save_state_light(state); +} + +void _kernel_fpsimd_load(struct fpsimd_state *state) +{ + if (!system_supports_fpsimd()) + return; + + BUG_ON(preemptible()); + if (test_thread_flag(TIF_KERNEL_FPSIMD)) + fpsimd_load_state_light(state); +} + +static void kernel_fpsimd_rollback_changes(void) +{ + if (!system_supports_fpsimd()) + return; + + BUG_ON(preemptible()); + if (test_thread_flag(TIF_KERNEL_FPSIMD)) { + fpsimd_save_state_light(&current->thread.kstate); + fpsimd_load_state_light(&current->thread.ustate); + } +} + +static void kernel_fpsimd_restore_changes(struct task_struct *tsk) +{ + if (!system_supports_fpsimd()) + return; + + BUG_ON(preemptible()); + if (test_ti_thread_flag(task_thread_info(tsk), TIF_KERNEL_FPSIMD)) { + fpsimd_save_state_light(&tsk->thread.ustate); + fpsimd_load_state_light(&tsk->thread.kstate); + } +} +#endif + #ifdef CONFIG_EFI static DEFINE_PER_CPU(struct user_fpsimd_state, efi_fpsimd_state); diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c index e9e5ce956f15..fd895189cb7e 100644 --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -529,7 +529,7 @@ struct task_struct *__switch_to(struct task_struct *prev, struct task_struct *next) { struct task_struct *last; - + uaccess_priviliged_context_switch(next); fpsimd_thread_switch(next); tls_thread_switch(next); hw_breakpoint_thread_switch(next); diff --git a/arch/arm64/lib/copy_from_user.S b/arch/arm64/lib/copy_from_user.S index 34e317907524..60dc63e10233 100644 --- a/arch/arm64/lib/copy_from_user.S +++ b/arch/arm64/lib/copy_from_user.S @@ -71,3 +71,33 @@ USER(9998f, ldtrb tmp1w, [srcin]) ret SYM_FUNC_END(__arch_copy_from_user) EXPORT_SYMBOL(__arch_copy_from_user) + + + +#ifdef CONFIG_USE_VECTORIZED_COPY + .macro ldsve reg1, reg2, reg3, reg4, ptr + USER(9997f, ld1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + + .macro stsve reg1, reg2, reg3, reg4, ptr + KERNEL_ME_SAFE(9998f, st1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + +SYM_FUNC_START(__arch_copy_from_user_fpsimd) + add end, x0, x2 + mov srcin, x1 +#include "copy_template_fpsimd.S" + mov x0, #0 // Nothing to copy + ret + + // Exception fixups +9997: cmp dst, dstin + b.ne 9998f + // Before being absolutely sure we couldn't copy anything, try harder +USER(9998f, ldtrb tmp1w, [srcin]) + strb tmp1w, [dst], #1 +9998: sub x0, end, dst // bytes not copied + ret +SYM_FUNC_END(__arch_copy_from_user_fpsimd) +EXPORT_SYMBOL(__arch_copy_from_user_fpsimd) +#endif \ No newline at end of file diff --git a/arch/arm64/lib/copy_template_fpsimd.S b/arch/arm64/lib/copy_template_fpsimd.S new file mode 100644 index 000000000000..9b2e7ce1e4d2 --- /dev/null +++ b/arch/arm64/lib/copy_template_fpsimd.S @@ -0,0 +1,180 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2013 ARM Ltd. + * Copyright (C) 2013 Linaro. + * + * This code is based on glibc cortex strings work originally authored by Linaro + * be found @ + * + * http://bazaar.launchpad.net/~linaro-toolchain-dev/cortex-strings/trunk/ + * files/head:/src/aarch64/ + */ + +/* + * Copy a buffer from src to dest (alignment handled by the hardware) + * + * Parameters: + * x0 - dest + * x1 - src + * x2 - n + * Returns: + * x0 - dest + */ +dstin .req x0 +src .req x1 +count .req x2 +tmp1 .req x3 +tmp1w .req w3 +tmp2 .req x4 +tmp2w .req w4 +dst .req x6 + +A_l .req x7 +A_h .req x8 +B_l .req x9 +B_h .req x10 +C_l .req x11 +C_h .req x12 +D_l .req x13 +D_h .req x14 + +V_a .req v20 +V_b .req v21 +V_c .req v22 +V_d .req v23 + + mov dst, dstin + cmp count, #16 + /*When memory length is less than 16, the accessed are not aligned.*/ + b.lo .Ltiny15_fpsimd + + neg tmp2, src + ands tmp2, tmp2, #15/* Bytes to reach alignment. */ + b.eq .LSrcAligned_fpsimd + sub count, count, tmp2 + /* + * Copy the leading memory data from src to dst in an increasing + * address order.By this way,the risk of overwriting the source + * memory data is eliminated when the distance between src and + * dst is less than 16. The memory accesses here are alignment. + */ + tbz tmp2, #0, 1f + ldrb1 tmp1w, src, #1 + strb1 tmp1w, dst, #1 +1: + tbz tmp2, #1, 2f + ldrh1 tmp1w, src, #2 + strh1 tmp1w, dst, #2 +2: + tbz tmp2, #2, 3f + ldr1 tmp1w, src, #4 + str1 tmp1w, dst, #4 +3: + tbz tmp2, #3, .LSrcAligned_fpsimd + ldr1 tmp1, src, #8 + str1 tmp1, dst, #8 + +.LSrcAligned_fpsimd: + cmp count, #64 + b.ge .Lcpy_over64_fpsimd + /* + * Deal with small copies quickly by dropping straight into the + * exit block. + */ +.Ltail63_fpsimd: + /* + * Copy up to 48 bytes of data. At this point we only need the + * bottom 6 bits of count to be accurate. + */ + ands tmp1, count, #0x30 + b.eq .Ltiny15_fpsimd + cmp tmp1w, #0x20 + b.eq 1f + b.lt 2f + ldp1 A_l, A_h, src, #16 + stp1 A_l, A_h, dst, #16 +1: + ldp1 A_l, A_h, src, #16 + stp1 A_l, A_h, dst, #16 +2: + ldp1 A_l, A_h, src, #16 + stp1 A_l, A_h, dst, #16 +.Ltiny15_fpsimd: + /* + * Prefer to break one ldp/stp into several load/store to access + * memory in an increasing address order,rather than to load/store 16 + * bytes from (src-16) to (dst-16) and to backward the src to aligned + * address,which way is used in original cortex memcpy. If keeping + * the original memcpy process here, memmove need to satisfy the + * precondition that src address is at least 16 bytes bigger than dst + * address,otherwise some source data will be overwritten when memove + * call memcpy directly. To make memmove simpler and decouple the + * memcpy's dependency on memmove, withdrew the original process. + */ + tbz count, #3, 1f + ldr1 tmp1, src, #8 + str1 tmp1, dst, #8 +1: + tbz count, #2, 2f + ldr1 tmp1w, src, #4 + str1 tmp1w, dst, #4 +2: + tbz count, #1, 3f + ldrh1 tmp1w, src, #2 + strh1 tmp1w, dst, #2 +3: + tbz count, #0, .Lexitfunc_fpsimd + ldrb1 tmp1w, src, #1 + strb1 tmp1w, dst, #1 + + b .Lexitfunc_fpsimd + +.Lcpy_over64_fpsimd: + subs count, count, #128 + b.ge .Lcpy_body_large_fpsimd + /* + * Less than 128 bytes to copy, so handle 64 here and then jump + * to the tail. + */ + ldp1 A_l, A_h, src, #16 + stp1 A_l, A_h, dst, #16 + ldp1 B_l, B_h, src, #16 + ldp1 C_l, C_h, src, #16 + stp1 B_l, B_h, dst, #16 + stp1 C_l, C_h, dst, #16 + ldp1 D_l, D_h, src, #16 + stp1 D_l, D_h, dst, #16 + + tst count, #0x3f + b.ne .Ltail63_fpsimd + b .Lexitfunc_fpsimd + + /* + * Critical loop. Start at a new cache line boundary. Assuming + * 64 bytes per line this ensures the entire loop is in one line. + */ + .p2align L1_CACHE_SHIFT +.Lcpy_body_large_fpsimd: + /* pre-get 64 bytes data. */ + ldsve V_a.16b, V_b.16b, V_c.16b, V_d.16b, src + add src, src, #64 + +1: + /* + * interlace the load of next 64 bytes data block with store of the last + * loaded 64 bytes data. + */ + stsve V_a.16b, V_b.16b, V_c.16b, V_d.16b, dst + ldsve V_a.16b, V_b.16b, V_c.16b, V_d.16b, src + add dst, dst, #64 + add src, src, #64 + + subs count, count, #64 + b.ge 1b + + stsve V_a.16b, V_b.16b, V_c.16b, V_d.16b, dst + add dst, dst, #64 + + tst count, #0x3f + b.ne .Ltail63_fpsimd +.Lexitfunc_fpsimd: diff --git a/arch/arm64/lib/copy_to_user.S b/arch/arm64/lib/copy_to_user.S index 2ac716c0d6d8..c190e5f8a989 100644 --- a/arch/arm64/lib/copy_to_user.S +++ b/arch/arm64/lib/copy_to_user.S @@ -71,3 +71,33 @@ USER(9998f, sttrb tmp1w, [dst]) ret SYM_FUNC_END(__arch_copy_to_user) EXPORT_SYMBOL(__arch_copy_to_user) + + +#ifdef CONFIG_USE_VECTORIZED_COPY + .macro stsve reg1, reg2, reg3, reg4, ptr + USER(9997f, st1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + + .macro ldsve reg1, reg2, reg3, reg4, ptr + KERNEL_ME_SAFE(9998f, ld1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + +SYM_FUNC_START(__arch_copy_to_user_fpsimd) + add end, x0, x2 + mov srcin, x1 +#include "copy_template_fpsimd.S" + mov x0, #0 + ret + + // Exception fixups +9997: cmp dst, dstin + b.ne 9998f + // Before being absolutely sure we couldn't copy anything, try harder +KERNEL_ME_SAFE(9998f, ldrb tmp1w, [srcin]) +USER(9998f, sttrb tmp1w, [dst]) + add dst, dst, #1 +9998: sub x0, end, dst // bytes not copied + ret +SYM_FUNC_END(__arch_copy_to_user_fpsimd) +EXPORT_SYMBOL(__arch_copy_to_user_fpsimd) +#endif diff --git a/kernel/softirq.c b/kernel/softirq.c index bd10ff418865..9935a11be1e8 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -30,6 +30,10 @@ #include <asm/softirq_stack.h> +#ifdef CONFIG_USE_VECTORIZED_COPY +#include <asm/fpsimd.h> +#endif + #define CREATE_TRACE_POINTS #include <trace/events/irq.h> @@ -542,6 +546,9 @@ static void handle_softirqs(bool ksirqd) __u32 pending; int softirq_bit; +#ifdef CONFIG_USE_VECTORIZED_COPY + struct fpsimd_state state; +#endif /* * Mask out PF_MEMALLOC as the current task context is borrowed for the * softirq. A softirq handled, such as network RX, might set PF_MEMALLOC @@ -551,10 +558,16 @@ static void handle_softirqs(bool ksirqd) pending = local_softirq_pending(); + softirq_handle_begin(); in_hardirq = lockdep_softirq_start(); account_softirq_enter(current); +#ifdef CONFIG_USE_VECTORIZED_COPY + _kernel_fpsimd_save(&state); + uaccess_priviliged_state_save(); +#endif + restart: /* Reset the pending bitmask before enabling irqs */ set_softirq_pending(0); @@ -603,7 +616,14 @@ static void handle_softirqs(bool ksirqd) account_softirq_exit(current); lockdep_softirq_end(in_hardirq); + +#ifdef CONFIG_USE_VECTORIZED_COPY + uaccess_priviliged_state_restore(); + _kernel_fpsimd_load(&state); +#endif + softirq_handle_end(); + current_restore_flags(old_flags, PF_MEMALLOC); } @@ -837,12 +857,21 @@ static void tasklet_action_common(struct softirq_action *a, { struct tasklet_struct *list; +#ifdef CONFIG_USE_VECTORIZED_COPY + struct fpsimd_state state; +#endif + local_irq_disable(); list = tl_head->head; tl_head->head = NULL; tl_head->tail = &tl_head->head; local_irq_enable(); +#ifdef CONFIG_USE_VECTORIZED_COPY + _kernel_fpsimd_save(&state); + uaccess_priviliged_state_save(); +#endif + while (list) { struct tasklet_struct *t = list; @@ -874,6 +903,11 @@ static void tasklet_action_common(struct softirq_action *a, __raise_softirq_irqoff(softirq_nr); local_irq_enable(); } + +#ifdef CONFIG_USE_VECTORIZED_COPY + uaccess_priviliged_state_restore(); + _kernel_fpsimd_load(&state); +#endif } static __latent_entropy void tasklet_action(struct softirq_action *a) diff --git a/kernel/sysctl.c b/kernel/sysctl.c index e84df0818517..6f8e22102bdc 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -137,6 +137,17 @@ int sysctl_legacy_va_layout; #endif /* CONFIG_SYSCTL */ +#ifdef CONFIG_USE_VECTORIZED_COPY +int sysctl_copy_to_user_threshold = -1; +EXPORT_SYMBOL(sysctl_copy_to_user_threshold); + +int sysctl_copy_from_user_threshold = -1; +EXPORT_SYMBOL(sysctl_copy_from_user_threshold); + +int sysctl_copy_in_user_threshold = -1; +EXPORT_SYMBOL(sysctl_copy_in_user_threshold); +#endif + /* * /proc/sys support */ @@ -2250,6 +2261,29 @@ static struct ctl_table vm_table[] = { .extra1 = (void *)&mmap_rnd_compat_bits_min, .extra2 = (void *)&mmap_rnd_compat_bits_max, }, +#endif +#ifdef CONFIG_USE_VECTORIZED_COPY + { + .procname = "copy_to_user_threshold", + .data = &sysctl_copy_to_user_threshold, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec + }, + { + .procname = "copy_from_user_threshold", + .data = &sysctl_copy_from_user_threshold, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec + }, + { + .procname = "copy_in_user_threshold", + .data = &sysctl_copy_in_user_threshold, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec + }, #endif { } }; -- 2.34.1

2 1

[PATCH v3 OLK-5.10] Add copy to/from/in user with vectorization support
by Nikita Panov 28 Jan '26

28 Jan '26

From: Artem Kuzin <artem.kuzin(a)huawei.com> kunpeng inclusion category: feature bugzilla: https://atomgit.com/openeuler/kernel/issues/8445 ------------------------------------------------- 1. This implementation uses st1/ld1 4-vector instructions which allow to copy 64 bytes at once 2. Copy code is used only if size of data block to copy is more than 128 bytes 4. To use this functionality you need to set configuration switch CONFIG_USE_VECTORIZED_COPY=y 5. Code can be used on any ARMv8 variant 6. In kernel copy functions like memcpy are not supported now, but can be enabled in future 7. For now we use lightweght version of register context saving/restoration (4-registers) We introduce support of vectorization for copy_from/to/in_user functions. Nowadays it works in parallel with original FPSIMD/SVE vectorization and doesn't affect it anyhow. We have special flag in task struct - TIF_KERNEL_FPSIMD, that set if currently we use lightweight vectorization in kernel. Task struct has been updated by two fields: user space fpsimd state and kernel fpsimd state. User space fpsimd state used by kernel_fpsimd_begin(), kernel_fpsimd_end() functions that wrap lightweight FPSIMD contexts usage in kernel space. Kernel fpsimd state is used to manage threads switch. Now there is no support of nested calls of kernel_neon_begin()/kernel_fpsimd_begin() and there is no plans to support this in future. This is not necessary. We save lightweight FPSIMD context in kernel_fpsimd_begin(), and restore it in /kernel_fpsimd_end(). On thread switch we preserve kernel FPSIMD context and restore user space one if any. This prevens curruption of user space FPSIMD state. Before switching to the next thread we restore it's kernel FPSIMD context if any. It is allowed to use FPSIMD in bottom halves, due to in case of BH preemption we check TIF_KERNEL_FPSIMD flag and save/restore contexts. Context management if quite lightweight and executed only in case of TIF_KERNEL_FPSIMD flag is set. To enable this feature, you need to manually modify one of the appropriate entries: /proc/sys/vm/copy_from_user_threshold /proc/sys/vm/copy_in_user_threshold /proc/sys/vm/copy_to_user_threshold Allowed values are following: -1 - feature enabled 0 - feature always enabled n (n >0) - feature enabled, if copied size is greater than n KB. P.S.: What I am personally don't like in current approach: 1. Additional fields and flag in task struct look quite ugly 2. No way to configure the size of chunk to copy using FPSIMD from user space 3. FPSIMD-based memory movement is not generic, need to enable for memmove(), memcpy() and friends in future. Co-developed-by: Alexander Kozhevnikov <alexander.kozhevnikov(a)huawei-partners.com> Signed-off-by: Alexander Kozhevnikov <alexander.kozhevnikov(a)huawei-partners.com> Co-developed-by: Nikita Panov <panov.nikita(a)huawei.com> Signed-off-by: Nikita Panov <panov.nikita(a)huawei.com> Signed-off-by: Artem Kuzin <artem.kuzin(a)huawei.com> --- arch/arm64/Kconfig | 15 ++ arch/arm64/configs/openeuler_defconfig | 2 + arch/arm64/include/asm/fpsimd.h | 15 ++ arch/arm64/include/asm/fpsimdmacros.h | 14 ++ arch/arm64/include/asm/neon.h | 28 +++ arch/arm64/include/asm/processor.h | 10 + arch/arm64/include/asm/thread_info.h | 4 + arch/arm64/include/asm/uaccess.h | 274 ++++++++++++++++++++++++- arch/arm64/kernel/entry-fpsimd.S | 22 ++ arch/arm64/kernel/fpsimd.c | 102 ++++++++- arch/arm64/kernel/process.c | 2 +- arch/arm64/lib/copy_from_user.S | 18 ++ arch/arm64/lib/copy_in_user.S | 19 ++ arch/arm64/lib/copy_template_fpsimd.S | 180 ++++++++++++++++ arch/arm64/lib/copy_to_user.S | 19 ++ kernel/softirq.c | 31 ++- kernel/sysctl.c | 35 ++++ 17 files changed, 782 insertions(+), 8 deletions(-) create mode 100644 arch/arm64/lib/copy_template_fpsimd.S diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index eb30ef59aca2..959af31f7e70 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -1470,6 +1470,21 @@ config ARM64_ILP32 is an ABI where long and pointers are 32bits but it uses the AARCH64 instruction set. +config USE_VECTORIZED_COPY + bool "Use vectorized instructions in copy_to/from user" + depends on KERNEL_MODE_NEON + default y + help + This option turns on vectorization to speed up copy_to/from_user routines. + +config VECTORIZED_COPY_VALIDATE + bool "Validate result of vectorized copy using regular implementation" + depends on KERNEL_MODE_NEON + depends on USE_VECTORIZED_COPY + default n + help + This option turns on vectorization to speed up copy_to/from_user routines. + menuconfig AARCH32_EL0 bool "Kernel support for 32-bit EL0" depends on ARM64_4K_PAGES || EXPERT diff --git a/arch/arm64/configs/openeuler_defconfig b/arch/arm64/configs/openeuler_defconfig index be1faf2da008..84408352a95e 100644 --- a/arch/arm64/configs/openeuler_defconfig +++ b/arch/arm64/configs/openeuler_defconfig @@ -484,6 +484,8 @@ CONFIG_ARM64_PMEM_RESERVE=y CONFIG_ARM64_PMEM_LEGACY=m # CONFIG_ARM64_SW_TTBR0_PAN is not set CONFIG_ARM64_TAGGED_ADDR_ABI=y +CONFIG_USE_VECTORIZED_COPY=y +# CONFIG_VECTORIZED_COPY_VALIDATE is not set CONFIG_AARCH32_EL0=y # CONFIG_KUSER_HELPERS is not set CONFIG_ARMV8_DEPRECATED=y diff --git a/arch/arm64/include/asm/fpsimd.h b/arch/arm64/include/asm/fpsimd.h index 22f6c6e23441..cb53767105ef 100644 --- a/arch/arm64/include/asm/fpsimd.h +++ b/arch/arm64/include/asm/fpsimd.h @@ -46,6 +46,21 @@ struct task_struct; +#ifdef CONFIG_USE_VECTORIZED_COPY +extern void fpsimd_save_state_light(struct fpsimd_state *state); +extern void fpsimd_load_state_light(struct fpsimd_state *state); +#else +static inline void fpsimd_save_state_light(struct fpsimd_state *state) +{ + (void) state; +} + +static inline void fpsimd_load_state_light(struct fpsimd_state *state) +{ + (void) state; +} +#endif + extern void fpsimd_save_state(struct user_fpsimd_state *state); extern void fpsimd_load_state(struct user_fpsimd_state *state); diff --git a/arch/arm64/include/asm/fpsimdmacros.h b/arch/arm64/include/asm/fpsimdmacros.h index ea2577e159f6..62f5f8a0540a 100644 --- a/arch/arm64/include/asm/fpsimdmacros.h +++ b/arch/arm64/include/asm/fpsimdmacros.h @@ -8,6 +8,20 @@ #include <asm/assembler.h> +#ifdef CONFIG_USE_VECTORIZED_COPY +/* Lightweight fpsimd context saving/restoration. + * Necessary for vectorized kernel memory movement + * implementation + */ +.macro fpsimd_save_light state + st1 {v20.16b, v21.16b, v22.16b, v23.16b}, [\state] +.endm + +.macro fpsimd_restore_light state + ld1 {v20.16b, v21.16b, v22.16b, v23.16b}, [\state] +.endm +#endif + .macro fpsimd_save state, tmpnr stp q0, q1, [\state, #16 * 0] stp q2, q3, [\state, #16 * 2] diff --git a/arch/arm64/include/asm/neon.h b/arch/arm64/include/asm/neon.h index d4b1d172a79b..ab84b194d7b3 100644 --- a/arch/arm64/include/asm/neon.h +++ b/arch/arm64/include/asm/neon.h @@ -16,4 +16,32 @@ void kernel_neon_begin(void); void kernel_neon_end(void); +#ifdef CONFIG_USE_VECTORIZED_COPY +bool kernel_fpsimd_begin(void); +void kernel_fpsimd_end(void); +/* Functions to use in non-preemptible context */ +void _kernel_fpsimd_save(struct fpsimd_state *state); +void _kernel_fpsimd_load(struct fpsimd_state *state); +#else +bool kernel_fpsimd_begin(void) +{ + return false; +} + +void kernel_fpsimd_end(void) +{ +} + +/* Functions to use in non-preemptible context */ +void _kernel_fpsimd_save(struct fpsimd_state *state) +{ + (void) state; +} + +void _kernel_fpsimd_load(struct fpsimd_state *state) +{ + (void) state; +} +#endif + #endif /* ! __ASM_NEON_H */ diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h index 66186f3ab550..d6ca823f7f0f 100644 --- a/arch/arm64/include/asm/processor.h +++ b/arch/arm64/include/asm/processor.h @@ -137,6 +137,10 @@ struct cpu_context { unsigned long pc; }; +struct fpsimd_state { + __uint128_t v[4]; +}; + struct thread_struct { struct cpu_context cpu_context; /* cpu context */ @@ -174,6 +178,12 @@ struct thread_struct { KABI_RESERVE(6) KABI_RESERVE(7) KABI_RESERVE(8) +#ifdef CONFIG_USE_VECTORIZED_COPY + KABI_EXTEND( + struct fpsimd_state ustate; + struct fpsimd_state kstate; + ) +#endif }; static inline unsigned int thread_get_vl(struct thread_struct *thread, diff --git a/arch/arm64/include/asm/thread_info.h b/arch/arm64/include/asm/thread_info.h index 390d9612546b..2e395ebcc856 100644 --- a/arch/arm64/include/asm/thread_info.h +++ b/arch/arm64/include/asm/thread_info.h @@ -89,6 +89,8 @@ void arch_release_task_struct(struct task_struct *tsk); #define TIF_PATCH_PENDING 28 /* pending live patching update */ #define TIF_SME 29 /* SME in use */ #define TIF_SME_VL_INHERIT 30 /* Inherit SME vl_onexec across exec */ +#define TIF_KERNEL_FPSIMD 31 /* Use FPSIMD in kernel */ +#define TIF_PRIV_UACC_ENABLED 32 /* Whether priviliged uaccess was manually enabled */ #define _TIF_SIGPENDING (1 << TIF_SIGPENDING) #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) @@ -108,6 +110,8 @@ void arch_release_task_struct(struct task_struct *tsk); #define _TIF_32BIT_AARCH64 (1 << TIF_32BIT_AARCH64) #define _TIF_PATCH_PENDING (1 << TIF_PATCH_PENDING) #define _TIF_POLLING_NRFLAG (1 << TIF_POLLING_NRFLAG) +#define _TIF_KERNEL_FPSIMD (1 << TIF_KERNEL_FPSIMD) +#define _TIF_PRIV_UACC_ENABLED (1 << TIF_PRIV_UACC_ENABLED) #define _TIF_WORK_MASK (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \ _TIF_NOTIFY_RESUME | _TIF_FOREIGN_FPSTATE | \ diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h index 03c2db710f92..4e4eec098cbc 100644 --- a/arch/arm64/include/asm/uaccess.h +++ b/arch/arm64/include/asm/uaccess.h @@ -24,6 +24,10 @@ #include <asm/memory.h> #include <asm/extable.h> +#ifndef __GENKSYMS__ +#include <asm/neon.h> +#endif + #define HAVE_GET_KERNEL_NOFAULT /* @@ -174,7 +178,7 @@ static inline void __uaccess_enable_hw_pan(void) CONFIG_ARM64_PAN)); } -static inline void uaccess_disable_privileged(void) +static inline void __uaccess_disable_privileged(void) { if (uaccess_ttbr0_disable()) return; @@ -182,7 +186,22 @@ static inline void uaccess_disable_privileged(void) __uaccess_enable_hw_pan(); } -static inline void uaccess_enable_privileged(void) +static inline void uaccess_disable_privileged(void) +{ + preempt_disable(); + + if (!test_and_clear_thread_flag(TIF_PRIV_UACC_ENABLED)) { + WARN_ON(1); + preempt_enable(); + return; + } + + __uaccess_disable_privileged(); + + preempt_enable(); +} + +static inline void __uaccess_enable_privileged(void) { if (uaccess_ttbr0_enable()) return; @@ -190,6 +209,47 @@ static inline void uaccess_enable_privileged(void) __uaccess_disable_hw_pan(); } +static inline void uaccess_enable_privileged(void) +{ + preempt_disable(); + + if (test_and_set_thread_flag(TIF_PRIV_UACC_ENABLED)) { + WARN_ON(1); + preempt_enable(); + return; + } + + __uaccess_enable_privileged(); + + preempt_enable(); +} + +static inline void uaccess_priviliged_context_switch(struct task_struct *next) +{ + bool curr_enabled = !!test_thread_flag(TIF_PRIV_UACC_ENABLED); + bool next_enabled = !!test_ti_thread_flag(&next->thread_info, TIF_PRIV_UACC_ENABLED); + + if (curr_enabled == next_enabled) + return; + + if (curr_enabled) + __uaccess_disable_privileged(); + else + __uaccess_enable_privileged(); +} + +static inline void uaccess_priviliged_state_save(void) +{ + if (test_thread_flag(TIF_PRIV_UACC_ENABLED)) + __uaccess_disable_privileged(); +} + +static inline void uaccess_priviliged_state_restore(void) +{ + if (test_thread_flag(TIF_PRIV_UACC_ENABLED)) + __uaccess_enable_privileged(); +} + /* * Sanitise a uaccess pointer such that it becomes NULL if above the maximum * user address. In case the pointer is tagged (has the top byte set), untag @@ -386,7 +446,97 @@ do { \ goto err_label; \ } while(0) -extern unsigned long __must_check __arch_copy_from_user(void *to, const void __user *from, unsigned long n); +#define USER_COPY_CHUNK_SIZE 4096 + +#ifdef CONFIG_USE_VECTORIZED_COPY + +extern int sysctl_copy_from_user_threshold; + +#define verify_fpsimd_copy(to, from, n, ret) \ +({ \ + unsigned long __verify_ret = 0; \ + __verify_ret = memcmp(to, from, ret ? n - ret : n); \ + if (__verify_ret) \ + pr_err("FPSIMD:%s inconsistent state\n", __func__); \ + if (ret) \ + pr_err("FPSIMD:%s failed to copy data, expected=%lu, copied=%lu\n", __func__, n, n - ret); \ + __verify_ret |= ret; \ + __verify_ret; \ +}) + +#define compare_fpsimd_copy(to, from, n, ret_fpsimd, ret) \ +({ \ + unsigned long __verify_ret = 0; \ + __verify_ret = memcmp(to, from, ret ? n - ret : n); \ + if (__verify_ret) \ + pr_err("FIXUP:%s inconsistent state\n", __func__); \ + if (ret) \ + pr_err("FIXUP:%s failed to copy data, expected=%lu, copied=%lu\n", __func__, n, n - ret); \ + __verify_ret |= ret; \ + if (ret_fpsimd != ret) { \ + pr_err("FIXUP:%s difference between FPSIMD %lu and regular %lu\n", __func__, n - ret_fpsimd, n - ret); \ + __verify_ret |= 1; \ + } else { \ + __verify_ret = 0; \ + } \ + __verify_ret; \ +}) + +extern unsigned long __must_check +__arch_copy_from_user(void *to, const void __user *from, unsigned long n); + +extern unsigned long __must_check +__arch_copy_from_user_fpsimd(void *to, const void __user *from, unsigned long n); + +static __always_inline unsigned long __must_check +raw_copy_from_user(void *to, const void __user *from, unsigned long n) +{ + unsigned long __acfu_ret; + + if (sysctl_copy_from_user_threshold == -1 || n < sysctl_copy_from_user_threshold) { + uaccess_ttbr0_enable(); + __acfu_ret = __arch_copy_from_user(to, + __uaccess_mask_ptr(from), n); + uaccess_ttbr0_disable(); + } else { + if (kernel_fpsimd_begin()) { + unsigned long __acfu_ret_fpsimd; + + uaccess_enable_privileged(); + __acfu_ret_fpsimd = __arch_copy_from_user_fpsimd((to), + __uaccess_mask_ptr(from), n); + uaccess_disable_privileged(); + + __acfu_ret = __acfu_ret_fpsimd; + kernel_fpsimd_end(); +#ifdef CONFIG_VECTORIZED_COPY_VALIDATE + if (verify_fpsimd_copy(to, __uaccess_mask_ptr(from), n, + __acfu_ret)) { + + uaccess_ttbr0_enable(); + __acfu_ret = __arch_copy_from_user((to), + __uaccess_mask_ptr(from), n); + uaccess_ttbr0_disable(); + + compare_fpsimd_copy(to, __uaccess_mask_ptr(from), n, + __acfu_ret_fpsimd, __acfu_ret); + } +#endif + } else { + uaccess_ttbr0_enable(); + __acfu_ret = __arch_copy_from_user((to), + __uaccess_mask_ptr(from), n); + uaccess_ttbr0_disable(); + } + } + + + return __acfu_ret; +} +#else +extern unsigned long __must_check +__arch_copy_from_user(void *to, const void __user *from, unsigned long n); + #define raw_copy_from_user(to, from, n) \ ({ \ unsigned long __acfu_ret; \ @@ -397,7 +547,66 @@ extern unsigned long __must_check __arch_copy_from_user(void *to, const void __u __acfu_ret; \ }) -extern unsigned long __must_check __arch_copy_to_user(void __user *to, const void *from, unsigned long n); +#endif + +#ifdef CONFIG_USE_VECTORIZED_COPY + +extern int sysctl_copy_to_user_threshold; + +extern unsigned long __must_check +__arch_copy_to_user(void __user *to, const void *from, unsigned long n); + +extern unsigned long __must_check +__arch_copy_to_user_fpsimd(void __user *to, const void *from, unsigned long n); + +static __always_inline unsigned long __must_check +raw_copy_to_user(void __user *to, const void *from, unsigned long n) +{ + unsigned long __actu_ret; + + + if (sysctl_copy_to_user_threshold == -1 || n < sysctl_copy_to_user_threshold) { + uaccess_ttbr0_enable(); + __actu_ret = __arch_copy_to_user(__uaccess_mask_ptr(to), + from, n); + uaccess_ttbr0_disable(); + } else { + if (kernel_fpsimd_begin()) { + unsigned long __actu_ret_fpsimd; + + uaccess_enable_privileged(); + __actu_ret_fpsimd = __arch_copy_to_user_fpsimd(__uaccess_mask_ptr(to), + from, n); + uaccess_disable_privileged(); + + kernel_fpsimd_end(); + __actu_ret = __actu_ret_fpsimd; +#ifdef CONFIG_VECTORIZED_COPY_VALIDATE + if (verify_fpsimd_copy(__uaccess_mask_ptr(to), from, n, + __actu_ret)) { + uaccess_ttbr0_enable(); + __actu_ret = __arch_copy_to_user(__uaccess_mask_ptr(to), + from, n); + uaccess_ttbr0_disable(); + + compare_fpsimd_copy(__uaccess_mask_ptr(to), from, n, + __actu_ret_fpsimd, __actu_ret); + } +#endif + } else { + uaccess_ttbr0_enable(); + __actu_ret = __arch_copy_to_user(__uaccess_mask_ptr(to), + from, n); + uaccess_ttbr0_disable(); + } + } + + return __actu_ret; +} +#else +extern unsigned long __must_check +__arch_copy_to_user(void __user *to, const void *from, unsigned long n); + #define raw_copy_to_user(to, from, n) \ ({ \ unsigned long __actu_ret; \ @@ -407,7 +616,62 @@ extern unsigned long __must_check __arch_copy_to_user(void __user *to, const voi uaccess_ttbr0_disable(); \ __actu_ret; \ }) +#endif +#ifdef CONFIG_USE_VECTORIZED_COPY + +extern int sysctl_copy_in_user_threshold; + +extern unsigned long __must_check +__arch_copy_in_user(void __user *to, const void __user *from, unsigned long n); + +extern unsigned long __must_check +__arch_copy_in_user_fpsimd(void __user *to, const void __user *from, unsigned long n); + +static __always_inline unsigned long __must_check +raw_copy_in_user(void __user *to, const void __user *from, unsigned long n) +{ + unsigned long __aciu_ret; + + if (sysctl_copy_in_user_threshold == -1 || n < sysctl_copy_in_user_threshold) { + uaccess_ttbr0_enable(); + __aciu_ret = __arch_copy_in_user(__uaccess_mask_ptr(to), + __uaccess_mask_ptr(from), n); + uaccess_ttbr0_disable(); + } else { + if (kernel_fpsimd_begin()) { + unsigned long __aciu_ret_fpsimd; + + uaccess_enable_privileged(); + __aciu_ret_fpsimd = __arch_copy_in_user_fpsimd(__uaccess_mask_ptr(to), + __uaccess_mask_ptr(from), n); + uaccess_disable_privileged(); + + kernel_fpsimd_end(); + __aciu_ret = __aciu_ret_fpsimd; +#ifdef CONFIG_VECTORIZED_COPY_VALIDATE + if (verify_fpsimd_copy(__uaccess_mask_ptr(to), __uaccess_mask_ptr(from), n, + __aciu_ret)) { + uaccess_ttbr0_enable(); + __aciu_ret = __arch_copy_in_user(__uaccess_mask_ptr(to), + __uaccess_mask_ptr(from), n); + uaccess_ttbr0_disable(); + + compare_fpsimd_copy(__uaccess_mask_ptr(to), __uaccess_mask_ptr(from), n, + __aciu_ret_fpsimd, __aciu_ret); + } +#endif + } else { + uaccess_ttbr0_enable(); + __aciu_ret = __arch_copy_in_user(__uaccess_mask_ptr(to), + __uaccess_mask_ptr(from), n); + uaccess_ttbr0_disable(); + } + } + + return __aciu_ret; +} +#else extern unsigned long __must_check __arch_copy_in_user(void __user *to, const void __user *from, unsigned long n); #define raw_copy_in_user(to, from, n) \ ({ \ @@ -419,6 +683,8 @@ extern unsigned long __must_check __arch_copy_in_user(void __user *to, const voi __aciu_ret; \ }) +#endif + #define INLINE_COPY_TO_USER #define INLINE_COPY_FROM_USER diff --git a/arch/arm64/kernel/entry-fpsimd.S b/arch/arm64/kernel/entry-fpsimd.S index 8d12aaac7862..848ca6a351d7 100644 --- a/arch/arm64/kernel/entry-fpsimd.S +++ b/arch/arm64/kernel/entry-fpsimd.S @@ -11,6 +11,28 @@ #include <asm/assembler.h> #include <asm/fpsimdmacros.h> +#ifdef CONFIG_USE_VECTORIZED_COPY +/* + * Save the FP registers. + * + * x0 - pointer to struct fpsimd_state_light + */ +SYM_FUNC_START(fpsimd_save_state_light) + fpsimd_save_light x0 + ret +SYM_FUNC_END(fpsimd_save_state_light) + +/* + * Load the FP registers. + * + * x0 - pointer to struct fpsimd_state_light + */ +SYM_FUNC_START(fpsimd_load_state_light) + fpsimd_restore_light x0 + ret +SYM_FUNC_END(fpsimd_load_state_light) +#endif + /* * Save the FP registers. * diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c index c2489a72b0b9..1a08c19a181f 100644 --- a/arch/arm64/kernel/fpsimd.c +++ b/arch/arm64/kernel/fpsimd.c @@ -1492,6 +1492,11 @@ void do_fpsimd_exc(unsigned int esr, struct pt_regs *regs) current); } +#ifdef CONFIG_USE_VECTORIZED_COPY +static void kernel_fpsimd_rollback_changes(void); +static void kernel_fpsimd_restore_changes(struct task_struct *tsk); +#endif + void fpsimd_thread_switch(struct task_struct *next) { bool wrong_task, wrong_cpu; @@ -1500,10 +1505,11 @@ void fpsimd_thread_switch(struct task_struct *next) return; __get_cpu_fpsimd_context(); - +#ifdef CONFIG_USE_VECTORIZED_COPY + kernel_fpsimd_rollback_changes(); +#endif /* Save unsaved fpsimd state, if any: */ fpsimd_save(); - /* * Fix up TIF_FOREIGN_FPSTATE to correctly describe next's * state. For kernel threads, FPSIMD registers are never loaded @@ -1516,6 +1522,9 @@ void fpsimd_thread_switch(struct task_struct *next) update_tsk_thread_flag(next, TIF_FOREIGN_FPSTATE, wrong_task || wrong_cpu); +#ifdef CONFIG_USE_VECTORIZED_COPY + kernel_fpsimd_restore_changes(next); +#endif __put_cpu_fpsimd_context(); } @@ -1835,6 +1844,95 @@ void kernel_neon_end(void) } EXPORT_SYMBOL(kernel_neon_end); +#ifdef CONFIG_USE_VECTORIZED_COPY +bool kernel_fpsimd_begin(void) +{ + if (WARN_ON(!system_capabilities_finalized()) || + !system_supports_fpsimd() || + in_irq() || irqs_disabled() || in_nmi()) + return false; + + preempt_disable(); + if (test_and_set_thread_flag(TIF_KERNEL_FPSIMD)) { + preempt_enable(); + + WARN_ON(1); + return false; + } + + /* + * Leaving streaming mode enabled will cause issues for any kernel + * NEON and leaving streaming mode or ZA enabled may increase power + * consumption. + */ + if (system_supports_sme()) + sme_smstop(); + + fpsimd_save_state_light(&current->thread.ustate); + preempt_enable(); + + return true; +} +EXPORT_SYMBOL(kernel_fpsimd_begin); + +void kernel_fpsimd_end(void) +{ + if (!system_supports_fpsimd()) + return; + + preempt_disable(); + if (test_and_clear_thread_flag(TIF_KERNEL_FPSIMD)) + fpsimd_load_state_light(&current->thread.ustate); + + preempt_enable(); +} +EXPORT_SYMBOL(kernel_fpsimd_end); + +void _kernel_fpsimd_save(struct fpsimd_state *state) +{ + if (!system_supports_fpsimd()) + return; + + BUG_ON(preemptible()); + if (test_thread_flag(TIF_KERNEL_FPSIMD)) + fpsimd_save_state_light(state); +} + +void _kernel_fpsimd_load(struct fpsimd_state *state) +{ + if (!system_supports_fpsimd()) + return; + + BUG_ON(preemptible()); + if (test_thread_flag(TIF_KERNEL_FPSIMD)) + fpsimd_load_state_light(state); +} + +static void kernel_fpsimd_rollback_changes(void) +{ + if (!system_supports_fpsimd()) + return; + + BUG_ON(preemptible()); + if (test_thread_flag(TIF_KERNEL_FPSIMD)) { + fpsimd_save_state_light(&current->thread.kstate); + fpsimd_load_state_light(&current->thread.ustate); + } +} + +static void kernel_fpsimd_restore_changes(struct task_struct *tsk) +{ + if (!system_supports_fpsimd()) + return; + + BUG_ON(preemptible()); + if (test_ti_thread_flag(task_thread_info(tsk), TIF_KERNEL_FPSIMD)) { + fpsimd_save_state_light(&tsk->thread.ustate); + fpsimd_load_state_light(&tsk->thread.kstate); + } +} +#endif + #ifdef CONFIG_EFI static DEFINE_PER_CPU(struct user_fpsimd_state, efi_fpsimd_state); diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c index 14300c9e06d5..338d40725a5d 100644 --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -572,7 +572,7 @@ __notrace_funcgraph struct task_struct *__switch_to(struct task_struct *prev, struct task_struct *next) { struct task_struct *last; - + uaccess_priviliged_context_switch(next); fpsimd_thread_switch(next); tls_thread_switch(next); hw_breakpoint_thread_switch(next); diff --git a/arch/arm64/lib/copy_from_user.S b/arch/arm64/lib/copy_from_user.S index dfc33ce09e72..94290069d97d 100644 --- a/arch/arm64/lib/copy_from_user.S +++ b/arch/arm64/lib/copy_from_user.S @@ -63,6 +63,24 @@ SYM_FUNC_START(__arch_copy_from_user) SYM_FUNC_END(__arch_copy_from_user) EXPORT_SYMBOL(__arch_copy_from_user) +#ifdef CONFIG_USE_VECTORIZED_COPY + .macro ldsve reg1, reg2, reg3, reg4, ptr + USER(9997f, ld1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + + .macro stsve reg1, reg2, reg3, reg4, ptr + USER_MC(9998f, st1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + +SYM_FUNC_START(__arch_copy_from_user_fpsimd) + add end, x0, x2 + mov srcin, x1 +#include "copy_template_fpsimd.S" + mov x0, #0 // Nothing to copy + ret +SYM_FUNC_END(__arch_copy_from_user_fpsimd) +EXPORT_SYMBOL(__arch_copy_from_user_fpsimd) +#endif .section .fixup,"ax" .align 2 9997: cmp dst, dstin diff --git a/arch/arm64/lib/copy_in_user.S b/arch/arm64/lib/copy_in_user.S index dbea3799c3ef..cbc09c377050 100644 --- a/arch/arm64/lib/copy_in_user.S +++ b/arch/arm64/lib/copy_in_user.S @@ -64,6 +64,25 @@ SYM_FUNC_START(__arch_copy_in_user) SYM_FUNC_END(__arch_copy_in_user) EXPORT_SYMBOL(__arch_copy_in_user) +#ifdef CONFIG_USE_VECTORIZED_COPY + .macro ldsve reg1, reg2, reg3, reg4, ptr + USER(9997f, ld1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + + .macro stsve reg1, reg2, reg3, reg4, ptr + USER(9997f, st1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + +SYM_FUNC_START(__arch_copy_in_user_fpsimd) + add end, x0, x2 + mov srcin, x1 +#include "copy_template_fpsimd.S" + mov x0, #0 + ret +SYM_FUNC_END(__arch_copy_in_user_fpsimd) +EXPORT_SYMBOL(__arch_copy_in_user_fpsimd) +#endif + .section .fixup,"ax" .align 2 9997: cmp dst, dstin diff --git a/arch/arm64/lib/copy_template_fpsimd.S b/arch/arm64/lib/copy_template_fpsimd.S new file mode 100644 index 000000000000..9b2e7ce1e4d2 --- /dev/null +++ b/arch/arm64/lib/copy_template_fpsimd.S @@ -0,0 +1,180 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2013 ARM Ltd. + * Copyright (C) 2013 Linaro. + * + * This code is based on glibc cortex strings work originally authored by Linaro + * be found @ + * + * http://bazaar.launchpad.net/~linaro-toolchain-dev/cortex-strings/trunk/ + * files/head:/src/aarch64/ + */ + +/* + * Copy a buffer from src to dest (alignment handled by the hardware) + * + * Parameters: + * x0 - dest + * x1 - src + * x2 - n + * Returns: + * x0 - dest + */ +dstin .req x0 +src .req x1 +count .req x2 +tmp1 .req x3 +tmp1w .req w3 +tmp2 .req x4 +tmp2w .req w4 +dst .req x6 + +A_l .req x7 +A_h .req x8 +B_l .req x9 +B_h .req x10 +C_l .req x11 +C_h .req x12 +D_l .req x13 +D_h .req x14 + +V_a .req v20 +V_b .req v21 +V_c .req v22 +V_d .req v23 + + mov dst, dstin + cmp count, #16 + /*When memory length is less than 16, the accessed are not aligned.*/ + b.lo .Ltiny15_fpsimd + + neg tmp2, src + ands tmp2, tmp2, #15/* Bytes to reach alignment. */ + b.eq .LSrcAligned_fpsimd + sub count, count, tmp2 + /* + * Copy the leading memory data from src to dst in an increasing + * address order.By this way,the risk of overwriting the source + * memory data is eliminated when the distance between src and + * dst is less than 16. The memory accesses here are alignment. + */ + tbz tmp2, #0, 1f + ldrb1 tmp1w, src, #1 + strb1 tmp1w, dst, #1 +1: + tbz tmp2, #1, 2f + ldrh1 tmp1w, src, #2 + strh1 tmp1w, dst, #2 +2: + tbz tmp2, #2, 3f + ldr1 tmp1w, src, #4 + str1 tmp1w, dst, #4 +3: + tbz tmp2, #3, .LSrcAligned_fpsimd + ldr1 tmp1, src, #8 + str1 tmp1, dst, #8 + +.LSrcAligned_fpsimd: + cmp count, #64 + b.ge .Lcpy_over64_fpsimd + /* + * Deal with small copies quickly by dropping straight into the + * exit block. + */ +.Ltail63_fpsimd: + /* + * Copy up to 48 bytes of data. At this point we only need the + * bottom 6 bits of count to be accurate. + */ + ands tmp1, count, #0x30 + b.eq .Ltiny15_fpsimd + cmp tmp1w, #0x20 + b.eq 1f + b.lt 2f + ldp1 A_l, A_h, src, #16 + stp1 A_l, A_h, dst, #16 +1: + ldp1 A_l, A_h, src, #16 + stp1 A_l, A_h, dst, #16 +2: + ldp1 A_l, A_h, src, #16 + stp1 A_l, A_h, dst, #16 +.Ltiny15_fpsimd: + /* + * Prefer to break one ldp/stp into several load/store to access + * memory in an increasing address order,rather than to load/store 16 + * bytes from (src-16) to (dst-16) and to backward the src to aligned + * address,which way is used in original cortex memcpy. If keeping + * the original memcpy process here, memmove need to satisfy the + * precondition that src address is at least 16 bytes bigger than dst + * address,otherwise some source data will be overwritten when memove + * call memcpy directly. To make memmove simpler and decouple the + * memcpy's dependency on memmove, withdrew the original process. + */ + tbz count, #3, 1f + ldr1 tmp1, src, #8 + str1 tmp1, dst, #8 +1: + tbz count, #2, 2f + ldr1 tmp1w, src, #4 + str1 tmp1w, dst, #4 +2: + tbz count, #1, 3f + ldrh1 tmp1w, src, #2 + strh1 tmp1w, dst, #2 +3: + tbz count, #0, .Lexitfunc_fpsimd + ldrb1 tmp1w, src, #1 + strb1 tmp1w, dst, #1 + + b .Lexitfunc_fpsimd + +.Lcpy_over64_fpsimd: + subs count, count, #128 + b.ge .Lcpy_body_large_fpsimd + /* + * Less than 128 bytes to copy, so handle 64 here and then jump + * to the tail. + */ + ldp1 A_l, A_h, src, #16 + stp1 A_l, A_h, dst, #16 + ldp1 B_l, B_h, src, #16 + ldp1 C_l, C_h, src, #16 + stp1 B_l, B_h, dst, #16 + stp1 C_l, C_h, dst, #16 + ldp1 D_l, D_h, src, #16 + stp1 D_l, D_h, dst, #16 + + tst count, #0x3f + b.ne .Ltail63_fpsimd + b .Lexitfunc_fpsimd + + /* + * Critical loop. Start at a new cache line boundary. Assuming + * 64 bytes per line this ensures the entire loop is in one line. + */ + .p2align L1_CACHE_SHIFT +.Lcpy_body_large_fpsimd: + /* pre-get 64 bytes data. */ + ldsve V_a.16b, V_b.16b, V_c.16b, V_d.16b, src + add src, src, #64 + +1: + /* + * interlace the load of next 64 bytes data block with store of the last + * loaded 64 bytes data. + */ + stsve V_a.16b, V_b.16b, V_c.16b, V_d.16b, dst + ldsve V_a.16b, V_b.16b, V_c.16b, V_d.16b, src + add dst, dst, #64 + add src, src, #64 + + subs count, count, #64 + b.ge 1b + + stsve V_a.16b, V_b.16b, V_c.16b, V_d.16b, dst + add dst, dst, #64 + + tst count, #0x3f + b.ne .Ltail63_fpsimd +.Lexitfunc_fpsimd: diff --git a/arch/arm64/lib/copy_to_user.S b/arch/arm64/lib/copy_to_user.S index 34154e7c8577..d0211fce4923 100644 --- a/arch/arm64/lib/copy_to_user.S +++ b/arch/arm64/lib/copy_to_user.S @@ -62,6 +62,25 @@ SYM_FUNC_START(__arch_copy_to_user) SYM_FUNC_END(__arch_copy_to_user) EXPORT_SYMBOL(__arch_copy_to_user) +#ifdef CONFIG_USE_VECTORIZED_COPY + .macro stsve reg1, reg2, reg3, reg4, ptr + USER(9997f, st1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + + .macro ldsve reg1, reg2, reg3, reg4, ptr + USER_MC(9998f, ld1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + +SYM_FUNC_START(__arch_copy_to_user_fpsimd) + add end, x0, x2 + mov srcin, x1 +#include "copy_template_fpsimd.S" + mov x0, #0 + ret +SYM_FUNC_END(__arch_copy_to_user_fpsimd) +EXPORT_SYMBOL(__arch_copy_to_user_fpsimd) +#endif + .section .fixup,"ax" .align 2 9997: cmp dst, dstin diff --git a/kernel/softirq.c b/kernel/softirq.c index 9fc69e6e2c11..e3f73422829d 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -26,6 +26,10 @@ #include <linux/tick.h> #include <linux/irq.h> +#ifdef CONFIG_USE_VECTORIZED_COPY +#include <asm/fpsimd.h> +#endif + #define CREATE_TRACE_POINTS #include <trace/events/irq.h> @@ -262,6 +266,9 @@ asmlinkage __visible void __softirq_entry __do_softirq(void) __u32 pending; int softirq_bit; +#ifdef CONFIG_USE_VECTORIZED_COPY + struct fpsimd_state state; +#endif /* * Mask out PF_MEMALLOC as the current task context is borrowed for the * softirq. A softirq handled, such as network RX, might set PF_MEMALLOC @@ -273,8 +280,11 @@ asmlinkage __visible void __softirq_entry __do_softirq(void) account_irq_enter_time(current); __local_bh_disable_ip(_RET_IP_, SOFTIRQ_OFFSET); +#ifdef CONFIG_USE_VECTORIZED_COPY + _kernel_fpsimd_save(&state); + uaccess_priviliged_state_save(); +#endif in_hardirq = lockdep_softirq_start(); - restart: /* Reset the pending bitmask before enabling irqs */ set_softirq_pending(0); @@ -322,6 +332,11 @@ asmlinkage __visible void __softirq_entry __do_softirq(void) lockdep_softirq_end(in_hardirq); account_irq_exit_time(current); + +#ifdef CONFIG_USE_VECTORIZED_COPY + uaccess_priviliged_state_restore(); + _kernel_fpsimd_load(&state); +#endif __local_bh_enable(SOFTIRQ_OFFSET); WARN_ON_ONCE(in_interrupt()); current_restore_flags(old_flags, PF_MEMALLOC); @@ -612,12 +627,21 @@ static void tasklet_action_common(struct softirq_action *a, { struct tasklet_struct *list; +#ifdef CONFIG_USE_VECTORIZED_COPY + struct fpsimd_state state; +#endif + local_irq_disable(); list = tl_head->head; tl_head->head = NULL; tl_head->tail = &tl_head->head; local_irq_enable(); +#ifdef CONFIG_USE_VECTORIZED_COPY + _kernel_fpsimd_save(&state); + uaccess_priviliged_state_save(); +#endif + while (list) { struct tasklet_struct *t = list; @@ -645,6 +669,11 @@ static void tasklet_action_common(struct softirq_action *a, __raise_softirq_irqoff(softirq_nr); local_irq_enable(); } + +#ifdef CONFIG_USE_VECTORIZED_COPY + uaccess_priviliged_state_restore(); + _kernel_fpsimd_load(&state); +#endif } static __latent_entropy void tasklet_action(struct softirq_action *a) diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 0b1c13a05332..9ec07294429b 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -210,6 +210,17 @@ static int max_extfrag_threshold = 1000; #endif /* CONFIG_SYSCTL */ +#ifdef CONFIG_USE_VECTORIZED_COPY +int sysctl_copy_to_user_threshold = -1; +EXPORT_SYMBOL(sysctl_copy_to_user_threshold); + +int sysctl_copy_from_user_threshold = -1; +EXPORT_SYMBOL(sysctl_copy_from_user_threshold); + +int sysctl_copy_in_user_threshold = -1; +EXPORT_SYMBOL(sysctl_copy_in_user_threshold); +#endif + #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_SYSCTL) static int bpf_stats_handler(struct ctl_table *table, int write, void *buffer, size_t *lenp, loff_t *ppos) @@ -3385,6 +3396,30 @@ static struct ctl_table vm_table[] = { .extra2 = SYSCTL_ONE, }, #endif + +#ifdef CONFIG_USE_VECTORIZED_COPY + { + .procname = "copy_to_user_threshold", + .data = &sysctl_copy_to_user_threshold, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec + }, + { + .procname = "copy_from_user_threshold", + .data = &sysctl_copy_from_user_threshold, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec + }, + { + .procname = "copy_in_user_threshold", + .data = &sysctl_copy_in_user_threshold, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec + }, +#endif { } }; -- 2.34.1

2 1

[PATCH v2 OLK-5.10] Add copy to/from/in user with vectorization support
by Nikita Panov 28 Jan '26

28 Jan '26

From: Artem Kuzin <artem.kuzin(a)huawei.com> kunpeng inclusion category: feature bugzilla: https://atomgit.com/openeuler/kernel/issues/8445 ------------------------------------------------- 1. This implementation uses st1/ld1 4-vector instructions which allow to copy 64 bytes at once 2. Copy code is used only if size of data block to copy is more than 128 bytes 4. To use this functionality you need to set configuration switch CONFIG_USE_VECTORIZED_COPY=y 5. Code can be used on any ARMv8 variant 6. In kernel copy functions like memcpy are not supported now, but can be enabled in future 7. For now we use lightweght version of register context saving/restoration (4-registers) We introduce support of vectorization for copy_from/to/in_user functions. Nowadays it works in parallel with original FPSIMD/SVE vectorization and doesn't affect it anyhow. We have special flag in task struct - TIF_KERNEL_FPSIMD, that set if currently we use lightweight vectorization in kernel. Task struct has been updated by two fields: user space fpsimd state and kernel fpsimd state. User space fpsimd state used by kernel_fpsimd_begin(), kernel_fpsimd_end() functions that wrap lightweight FPSIMD contexts usage in kernel space. Kernel fpsimd state is used to manage threads switch. Now there is no support of nested calls of kernel_neon_begin()/kernel_fpsimd_begin() and there is no plans to support this in future. This is not necessary. We save lightweight FPSIMD context in kernel_fpsimd_begin(), and restore it in /kernel_fpsimd_end(). On thread switch we preserve kernel FPSIMD context and restore user space one if any. This prevens curruption of user space FPSIMD state. Before switching to the next thread we restore it's kernel FPSIMD context if any. It is allowed to use FPSIMD in bottom halves, due to in case of BH preemption we check TIF_KERNEL_FPSIMD flag and save/restore contexts. Context management if quite lightweight and executed only in case of TIF_KERNEL_FPSIMD flag is set. To enable this feature, you need to manually modify one of the appropriate entries: /proc/sys/vm/copy_from_user_threshold /proc/sys/vm/copy_in_user_threshold /proc/sys/vm/copy_to_user_threshold Allowed values are following: -1 - feature enabled 0 - feature always enabled n (n >0) - feature enabled, if copied size is greater than n KB. P.S.: What I am personally don't like in current approach: 1. Additional fields and flag in task struct look quite ugly 2. No way to configure the size of chunk to copy using FPSIMD from user space 3. FPSIMD-based memory movement is not generic, need to enable for memmove(), memcpy() and friends in future. Co-developed-by: Alexander Kozhevnikov <alexander.kozhevnikov(a)huawei-partners.com> Signed-off-by: Alexander Kozhevnikov <alexander.kozhevnikov(a)huawei-partners.com> Co-developed-by: Nikita Panov <panov.nikita(a)huawei.com> Signed-off-by: Nikita Panov <panov.nikita(a)huawei.com> Signed-off-by: Artem Kuzin <artem.kuzin(a)huawei.com> --- arch/arm64/Kconfig | 15 ++ arch/arm64/include/asm/fpsimd.h | 15 ++ arch/arm64/include/asm/fpsimdmacros.h | 14 ++ arch/arm64/include/asm/neon.h | 28 +++ arch/arm64/include/asm/processor.h | 10 + arch/arm64/include/asm/thread_info.h | 4 + arch/arm64/include/asm/uaccess.h | 274 +++++++++++++++++++++++++- arch/arm64/kernel/entry-fpsimd.S | 22 +++ arch/arm64/kernel/fpsimd.c | 102 +++++++++- arch/arm64/kernel/process.c | 2 +- arch/arm64/lib/copy_from_user.S | 18 ++ arch/arm64/lib/copy_in_user.S | 19 ++ arch/arm64/lib/copy_template_fpsimd.S | 180 +++++++++++++++++ arch/arm64/lib/copy_to_user.S | 19 ++ kernel/softirq.c | 31 ++- kernel/sysctl.c | 35 ++++ 16 files changed, 780 insertions(+), 8 deletions(-) create mode 100644 arch/arm64/lib/copy_template_fpsimd.S diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index eb30ef59aca2..959af31f7e70 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -1470,6 +1470,21 @@ config ARM64_ILP32 is an ABI where long and pointers are 32bits but it uses the AARCH64 instruction set. +config USE_VECTORIZED_COPY + bool "Use vectorized instructions in copy_to/from user" + depends on KERNEL_MODE_NEON + default y + help + This option turns on vectorization to speed up copy_to/from_user routines. + +config VECTORIZED_COPY_VALIDATE + bool "Validate result of vectorized copy using regular implementation" + depends on KERNEL_MODE_NEON + depends on USE_VECTORIZED_COPY + default n + help + This option turns on vectorization to speed up copy_to/from_user routines. + menuconfig AARCH32_EL0 bool "Kernel support for 32-bit EL0" depends on ARM64_4K_PAGES || EXPERT diff --git a/arch/arm64/include/asm/fpsimd.h b/arch/arm64/include/asm/fpsimd.h index 22f6c6e23441..cb53767105ef 100644 --- a/arch/arm64/include/asm/fpsimd.h +++ b/arch/arm64/include/asm/fpsimd.h @@ -46,6 +46,21 @@ struct task_struct; +#ifdef CONFIG_USE_VECTORIZED_COPY +extern void fpsimd_save_state_light(struct fpsimd_state *state); +extern void fpsimd_load_state_light(struct fpsimd_state *state); +#else +static inline void fpsimd_save_state_light(struct fpsimd_state *state) +{ + (void) state; +} + +static inline void fpsimd_load_state_light(struct fpsimd_state *state) +{ + (void) state; +} +#endif + extern void fpsimd_save_state(struct user_fpsimd_state *state); extern void fpsimd_load_state(struct user_fpsimd_state *state); diff --git a/arch/arm64/include/asm/fpsimdmacros.h b/arch/arm64/include/asm/fpsimdmacros.h index ea2577e159f6..62f5f8a0540a 100644 --- a/arch/arm64/include/asm/fpsimdmacros.h +++ b/arch/arm64/include/asm/fpsimdmacros.h @@ -8,6 +8,20 @@ #include <asm/assembler.h> +#ifdef CONFIG_USE_VECTORIZED_COPY +/* Lightweight fpsimd context saving/restoration. + * Necessary for vectorized kernel memory movement + * implementation + */ +.macro fpsimd_save_light state + st1 {v20.16b, v21.16b, v22.16b, v23.16b}, [\state] +.endm + +.macro fpsimd_restore_light state + ld1 {v20.16b, v21.16b, v22.16b, v23.16b}, [\state] +.endm +#endif + .macro fpsimd_save state, tmpnr stp q0, q1, [\state, #16 * 0] stp q2, q3, [\state, #16 * 2] diff --git a/arch/arm64/include/asm/neon.h b/arch/arm64/include/asm/neon.h index d4b1d172a79b..ab84b194d7b3 100644 --- a/arch/arm64/include/asm/neon.h +++ b/arch/arm64/include/asm/neon.h @@ -16,4 +16,32 @@ void kernel_neon_begin(void); void kernel_neon_end(void); +#ifdef CONFIG_USE_VECTORIZED_COPY +bool kernel_fpsimd_begin(void); +void kernel_fpsimd_end(void); +/* Functions to use in non-preemptible context */ +void _kernel_fpsimd_save(struct fpsimd_state *state); +void _kernel_fpsimd_load(struct fpsimd_state *state); +#else +bool kernel_fpsimd_begin(void) +{ + return false; +} + +void kernel_fpsimd_end(void) +{ +} + +/* Functions to use in non-preemptible context */ +void _kernel_fpsimd_save(struct fpsimd_state *state) +{ + (void) state; +} + +void _kernel_fpsimd_load(struct fpsimd_state *state) +{ + (void) state; +} +#endif + #endif /* ! __ASM_NEON_H */ diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h index 66186f3ab550..d6ca823f7f0f 100644 --- a/arch/arm64/include/asm/processor.h +++ b/arch/arm64/include/asm/processor.h @@ -137,6 +137,10 @@ struct cpu_context { unsigned long pc; }; +struct fpsimd_state { + __uint128_t v[4]; +}; + struct thread_struct { struct cpu_context cpu_context; /* cpu context */ @@ -174,6 +178,12 @@ struct thread_struct { KABI_RESERVE(6) KABI_RESERVE(7) KABI_RESERVE(8) +#ifdef CONFIG_USE_VECTORIZED_COPY + KABI_EXTEND( + struct fpsimd_state ustate; + struct fpsimd_state kstate; + ) +#endif }; static inline unsigned int thread_get_vl(struct thread_struct *thread, diff --git a/arch/arm64/include/asm/thread_info.h b/arch/arm64/include/asm/thread_info.h index 390d9612546b..2e395ebcc856 100644 --- a/arch/arm64/include/asm/thread_info.h +++ b/arch/arm64/include/asm/thread_info.h @@ -89,6 +89,8 @@ void arch_release_task_struct(struct task_struct *tsk); #define TIF_PATCH_PENDING 28 /* pending live patching update */ #define TIF_SME 29 /* SME in use */ #define TIF_SME_VL_INHERIT 30 /* Inherit SME vl_onexec across exec */ +#define TIF_KERNEL_FPSIMD 31 /* Use FPSIMD in kernel */ +#define TIF_PRIV_UACC_ENABLED 32 /* Whether priviliged uaccess was manually enabled */ #define _TIF_SIGPENDING (1 << TIF_SIGPENDING) #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) @@ -108,6 +110,8 @@ void arch_release_task_struct(struct task_struct *tsk); #define _TIF_32BIT_AARCH64 (1 << TIF_32BIT_AARCH64) #define _TIF_PATCH_PENDING (1 << TIF_PATCH_PENDING) #define _TIF_POLLING_NRFLAG (1 << TIF_POLLING_NRFLAG) +#define _TIF_KERNEL_FPSIMD (1 << TIF_KERNEL_FPSIMD) +#define _TIF_PRIV_UACC_ENABLED (1 << TIF_PRIV_UACC_ENABLED) #define _TIF_WORK_MASK (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \ _TIF_NOTIFY_RESUME | _TIF_FOREIGN_FPSTATE | \ diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h index 03c2db710f92..4e4eec098cbc 100644 --- a/arch/arm64/include/asm/uaccess.h +++ b/arch/arm64/include/asm/uaccess.h @@ -24,6 +24,10 @@ #include <asm/memory.h> #include <asm/extable.h> +#ifndef __GENKSYMS__ +#include <asm/neon.h> +#endif + #define HAVE_GET_KERNEL_NOFAULT /* @@ -174,7 +178,7 @@ static inline void __uaccess_enable_hw_pan(void) CONFIG_ARM64_PAN)); } -static inline void uaccess_disable_privileged(void) +static inline void __uaccess_disable_privileged(void) { if (uaccess_ttbr0_disable()) return; @@ -182,7 +186,22 @@ static inline void uaccess_disable_privileged(void) __uaccess_enable_hw_pan(); } -static inline void uaccess_enable_privileged(void) +static inline void uaccess_disable_privileged(void) +{ + preempt_disable(); + + if (!test_and_clear_thread_flag(TIF_PRIV_UACC_ENABLED)) { + WARN_ON(1); + preempt_enable(); + return; + } + + __uaccess_disable_privileged(); + + preempt_enable(); +} + +static inline void __uaccess_enable_privileged(void) { if (uaccess_ttbr0_enable()) return; @@ -190,6 +209,47 @@ static inline void uaccess_enable_privileged(void) __uaccess_disable_hw_pan(); } +static inline void uaccess_enable_privileged(void) +{ + preempt_disable(); + + if (test_and_set_thread_flag(TIF_PRIV_UACC_ENABLED)) { + WARN_ON(1); + preempt_enable(); + return; + } + + __uaccess_enable_privileged(); + + preempt_enable(); +} + +static inline void uaccess_priviliged_context_switch(struct task_struct *next) +{ + bool curr_enabled = !!test_thread_flag(TIF_PRIV_UACC_ENABLED); + bool next_enabled = !!test_ti_thread_flag(&next->thread_info, TIF_PRIV_UACC_ENABLED); + + if (curr_enabled == next_enabled) + return; + + if (curr_enabled) + __uaccess_disable_privileged(); + else + __uaccess_enable_privileged(); +} + +static inline void uaccess_priviliged_state_save(void) +{ + if (test_thread_flag(TIF_PRIV_UACC_ENABLED)) + __uaccess_disable_privileged(); +} + +static inline void uaccess_priviliged_state_restore(void) +{ + if (test_thread_flag(TIF_PRIV_UACC_ENABLED)) + __uaccess_enable_privileged(); +} + /* * Sanitise a uaccess pointer such that it becomes NULL if above the maximum * user address. In case the pointer is tagged (has the top byte set), untag @@ -386,7 +446,97 @@ do { \ goto err_label; \ } while(0) -extern unsigned long __must_check __arch_copy_from_user(void *to, const void __user *from, unsigned long n); +#define USER_COPY_CHUNK_SIZE 4096 + +#ifdef CONFIG_USE_VECTORIZED_COPY + +extern int sysctl_copy_from_user_threshold; + +#define verify_fpsimd_copy(to, from, n, ret) \ +({ \ + unsigned long __verify_ret = 0; \ + __verify_ret = memcmp(to, from, ret ? n - ret : n); \ + if (__verify_ret) \ + pr_err("FPSIMD:%s inconsistent state\n", __func__); \ + if (ret) \ + pr_err("FPSIMD:%s failed to copy data, expected=%lu, copied=%lu\n", __func__, n, n - ret); \ + __verify_ret |= ret; \ + __verify_ret; \ +}) + +#define compare_fpsimd_copy(to, from, n, ret_fpsimd, ret) \ +({ \ + unsigned long __verify_ret = 0; \ + __verify_ret = memcmp(to, from, ret ? n - ret : n); \ + if (__verify_ret) \ + pr_err("FIXUP:%s inconsistent state\n", __func__); \ + if (ret) \ + pr_err("FIXUP:%s failed to copy data, expected=%lu, copied=%lu\n", __func__, n, n - ret); \ + __verify_ret |= ret; \ + if (ret_fpsimd != ret) { \ + pr_err("FIXUP:%s difference between FPSIMD %lu and regular %lu\n", __func__, n - ret_fpsimd, n - ret); \ + __verify_ret |= 1; \ + } else { \ + __verify_ret = 0; \ + } \ + __verify_ret; \ +}) + +extern unsigned long __must_check +__arch_copy_from_user(void *to, const void __user *from, unsigned long n); + +extern unsigned long __must_check +__arch_copy_from_user_fpsimd(void *to, const void __user *from, unsigned long n); + +static __always_inline unsigned long __must_check +raw_copy_from_user(void *to, const void __user *from, unsigned long n) +{ + unsigned long __acfu_ret; + + if (sysctl_copy_from_user_threshold == -1 || n < sysctl_copy_from_user_threshold) { + uaccess_ttbr0_enable(); + __acfu_ret = __arch_copy_from_user(to, + __uaccess_mask_ptr(from), n); + uaccess_ttbr0_disable(); + } else { + if (kernel_fpsimd_begin()) { + unsigned long __acfu_ret_fpsimd; + + uaccess_enable_privileged(); + __acfu_ret_fpsimd = __arch_copy_from_user_fpsimd((to), + __uaccess_mask_ptr(from), n); + uaccess_disable_privileged(); + + __acfu_ret = __acfu_ret_fpsimd; + kernel_fpsimd_end(); +#ifdef CONFIG_VECTORIZED_COPY_VALIDATE + if (verify_fpsimd_copy(to, __uaccess_mask_ptr(from), n, + __acfu_ret)) { + + uaccess_ttbr0_enable(); + __acfu_ret = __arch_copy_from_user((to), + __uaccess_mask_ptr(from), n); + uaccess_ttbr0_disable(); + + compare_fpsimd_copy(to, __uaccess_mask_ptr(from), n, + __acfu_ret_fpsimd, __acfu_ret); + } +#endif + } else { + uaccess_ttbr0_enable(); + __acfu_ret = __arch_copy_from_user((to), + __uaccess_mask_ptr(from), n); + uaccess_ttbr0_disable(); + } + } + + + return __acfu_ret; +} +#else +extern unsigned long __must_check +__arch_copy_from_user(void *to, const void __user *from, unsigned long n); + #define raw_copy_from_user(to, from, n) \ ({ \ unsigned long __acfu_ret; \ @@ -397,7 +547,66 @@ extern unsigned long __must_check __arch_copy_from_user(void *to, const void __u __acfu_ret; \ }) -extern unsigned long __must_check __arch_copy_to_user(void __user *to, const void *from, unsigned long n); +#endif + +#ifdef CONFIG_USE_VECTORIZED_COPY + +extern int sysctl_copy_to_user_threshold; + +extern unsigned long __must_check +__arch_copy_to_user(void __user *to, const void *from, unsigned long n); + +extern unsigned long __must_check +__arch_copy_to_user_fpsimd(void __user *to, const void *from, unsigned long n); + +static __always_inline unsigned long __must_check +raw_copy_to_user(void __user *to, const void *from, unsigned long n) +{ + unsigned long __actu_ret; + + + if (sysctl_copy_to_user_threshold == -1 || n < sysctl_copy_to_user_threshold) { + uaccess_ttbr0_enable(); + __actu_ret = __arch_copy_to_user(__uaccess_mask_ptr(to), + from, n); + uaccess_ttbr0_disable(); + } else { + if (kernel_fpsimd_begin()) { + unsigned long __actu_ret_fpsimd; + + uaccess_enable_privileged(); + __actu_ret_fpsimd = __arch_copy_to_user_fpsimd(__uaccess_mask_ptr(to), + from, n); + uaccess_disable_privileged(); + + kernel_fpsimd_end(); + __actu_ret = __actu_ret_fpsimd; +#ifdef CONFIG_VECTORIZED_COPY_VALIDATE + if (verify_fpsimd_copy(__uaccess_mask_ptr(to), from, n, + __actu_ret)) { + uaccess_ttbr0_enable(); + __actu_ret = __arch_copy_to_user(__uaccess_mask_ptr(to), + from, n); + uaccess_ttbr0_disable(); + + compare_fpsimd_copy(__uaccess_mask_ptr(to), from, n, + __actu_ret_fpsimd, __actu_ret); + } +#endif + } else { + uaccess_ttbr0_enable(); + __actu_ret = __arch_copy_to_user(__uaccess_mask_ptr(to), + from, n); + uaccess_ttbr0_disable(); + } + } + + return __actu_ret; +} +#else +extern unsigned long __must_check +__arch_copy_to_user(void __user *to, const void *from, unsigned long n); + #define raw_copy_to_user(to, from, n) \ ({ \ unsigned long __actu_ret; \ @@ -407,7 +616,62 @@ extern unsigned long __must_check __arch_copy_to_user(void __user *to, const voi uaccess_ttbr0_disable(); \ __actu_ret; \ }) +#endif +#ifdef CONFIG_USE_VECTORIZED_COPY + +extern int sysctl_copy_in_user_threshold; + +extern unsigned long __must_check +__arch_copy_in_user(void __user *to, const void __user *from, unsigned long n); + +extern unsigned long __must_check +__arch_copy_in_user_fpsimd(void __user *to, const void __user *from, unsigned long n); + +static __always_inline unsigned long __must_check +raw_copy_in_user(void __user *to, const void __user *from, unsigned long n) +{ + unsigned long __aciu_ret; + + if (sysctl_copy_in_user_threshold == -1 || n < sysctl_copy_in_user_threshold) { + uaccess_ttbr0_enable(); + __aciu_ret = __arch_copy_in_user(__uaccess_mask_ptr(to), + __uaccess_mask_ptr(from), n); + uaccess_ttbr0_disable(); + } else { + if (kernel_fpsimd_begin()) { + unsigned long __aciu_ret_fpsimd; + + uaccess_enable_privileged(); + __aciu_ret_fpsimd = __arch_copy_in_user_fpsimd(__uaccess_mask_ptr(to), + __uaccess_mask_ptr(from), n); + uaccess_disable_privileged(); + + kernel_fpsimd_end(); + __aciu_ret = __aciu_ret_fpsimd; +#ifdef CONFIG_VECTORIZED_COPY_VALIDATE + if (verify_fpsimd_copy(__uaccess_mask_ptr(to), __uaccess_mask_ptr(from), n, + __aciu_ret)) { + uaccess_ttbr0_enable(); + __aciu_ret = __arch_copy_in_user(__uaccess_mask_ptr(to), + __uaccess_mask_ptr(from), n); + uaccess_ttbr0_disable(); + + compare_fpsimd_copy(__uaccess_mask_ptr(to), __uaccess_mask_ptr(from), n, + __aciu_ret_fpsimd, __aciu_ret); + } +#endif + } else { + uaccess_ttbr0_enable(); + __aciu_ret = __arch_copy_in_user(__uaccess_mask_ptr(to), + __uaccess_mask_ptr(from), n); + uaccess_ttbr0_disable(); + } + } + + return __aciu_ret; +} +#else extern unsigned long __must_check __arch_copy_in_user(void __user *to, const void __user *from, unsigned long n); #define raw_copy_in_user(to, from, n) \ ({ \ @@ -419,6 +683,8 @@ extern unsigned long __must_check __arch_copy_in_user(void __user *to, const voi __aciu_ret; \ }) +#endif + #define INLINE_COPY_TO_USER #define INLINE_COPY_FROM_USER diff --git a/arch/arm64/kernel/entry-fpsimd.S b/arch/arm64/kernel/entry-fpsimd.S index 8d12aaac7862..848ca6a351d7 100644 --- a/arch/arm64/kernel/entry-fpsimd.S +++ b/arch/arm64/kernel/entry-fpsimd.S @@ -11,6 +11,28 @@ #include <asm/assembler.h> #include <asm/fpsimdmacros.h> +#ifdef CONFIG_USE_VECTORIZED_COPY +/* + * Save the FP registers. + * + * x0 - pointer to struct fpsimd_state_light + */ +SYM_FUNC_START(fpsimd_save_state_light) + fpsimd_save_light x0 + ret +SYM_FUNC_END(fpsimd_save_state_light) + +/* + * Load the FP registers. + * + * x0 - pointer to struct fpsimd_state_light + */ +SYM_FUNC_START(fpsimd_load_state_light) + fpsimd_restore_light x0 + ret +SYM_FUNC_END(fpsimd_load_state_light) +#endif + /* * Save the FP registers. * diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c index c2489a72b0b9..1a08c19a181f 100644 --- a/arch/arm64/kernel/fpsimd.c +++ b/arch/arm64/kernel/fpsimd.c @@ -1492,6 +1492,11 @@ void do_fpsimd_exc(unsigned int esr, struct pt_regs *regs) current); } +#ifdef CONFIG_USE_VECTORIZED_COPY +static void kernel_fpsimd_rollback_changes(void); +static void kernel_fpsimd_restore_changes(struct task_struct *tsk); +#endif + void fpsimd_thread_switch(struct task_struct *next) { bool wrong_task, wrong_cpu; @@ -1500,10 +1505,11 @@ void fpsimd_thread_switch(struct task_struct *next) return; __get_cpu_fpsimd_context(); - +#ifdef CONFIG_USE_VECTORIZED_COPY + kernel_fpsimd_rollback_changes(); +#endif /* Save unsaved fpsimd state, if any: */ fpsimd_save(); - /* * Fix up TIF_FOREIGN_FPSTATE to correctly describe next's * state. For kernel threads, FPSIMD registers are never loaded @@ -1516,6 +1522,9 @@ void fpsimd_thread_switch(struct task_struct *next) update_tsk_thread_flag(next, TIF_FOREIGN_FPSTATE, wrong_task || wrong_cpu); +#ifdef CONFIG_USE_VECTORIZED_COPY + kernel_fpsimd_restore_changes(next); +#endif __put_cpu_fpsimd_context(); } @@ -1835,6 +1844,95 @@ void kernel_neon_end(void) } EXPORT_SYMBOL(kernel_neon_end); +#ifdef CONFIG_USE_VECTORIZED_COPY +bool kernel_fpsimd_begin(void) +{ + if (WARN_ON(!system_capabilities_finalized()) || + !system_supports_fpsimd() || + in_irq() || irqs_disabled() || in_nmi()) + return false; + + preempt_disable(); + if (test_and_set_thread_flag(TIF_KERNEL_FPSIMD)) { + preempt_enable(); + + WARN_ON(1); + return false; + } + + /* + * Leaving streaming mode enabled will cause issues for any kernel + * NEON and leaving streaming mode or ZA enabled may increase power + * consumption. + */ + if (system_supports_sme()) + sme_smstop(); + + fpsimd_save_state_light(&current->thread.ustate); + preempt_enable(); + + return true; +} +EXPORT_SYMBOL(kernel_fpsimd_begin); + +void kernel_fpsimd_end(void) +{ + if (!system_supports_fpsimd()) + return; + + preempt_disable(); + if (test_and_clear_thread_flag(TIF_KERNEL_FPSIMD)) + fpsimd_load_state_light(&current->thread.ustate); + + preempt_enable(); +} +EXPORT_SYMBOL(kernel_fpsimd_end); + +void _kernel_fpsimd_save(struct fpsimd_state *state) +{ + if (!system_supports_fpsimd()) + return; + + BUG_ON(preemptible()); + if (test_thread_flag(TIF_KERNEL_FPSIMD)) + fpsimd_save_state_light(state); +} + +void _kernel_fpsimd_load(struct fpsimd_state *state) +{ + if (!system_supports_fpsimd()) + return; + + BUG_ON(preemptible()); + if (test_thread_flag(TIF_KERNEL_FPSIMD)) + fpsimd_load_state_light(state); +} + +static void kernel_fpsimd_rollback_changes(void) +{ + if (!system_supports_fpsimd()) + return; + + BUG_ON(preemptible()); + if (test_thread_flag(TIF_KERNEL_FPSIMD)) { + fpsimd_save_state_light(&current->thread.kstate); + fpsimd_load_state_light(&current->thread.ustate); + } +} + +static void kernel_fpsimd_restore_changes(struct task_struct *tsk) +{ + if (!system_supports_fpsimd()) + return; + + BUG_ON(preemptible()); + if (test_ti_thread_flag(task_thread_info(tsk), TIF_KERNEL_FPSIMD)) { + fpsimd_save_state_light(&tsk->thread.ustate); + fpsimd_load_state_light(&tsk->thread.kstate); + } +} +#endif + #ifdef CONFIG_EFI static DEFINE_PER_CPU(struct user_fpsimd_state, efi_fpsimd_state); diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c index 14300c9e06d5..338d40725a5d 100644 --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -572,7 +572,7 @@ __notrace_funcgraph struct task_struct *__switch_to(struct task_struct *prev, struct task_struct *next) { struct task_struct *last; - + uaccess_priviliged_context_switch(next); fpsimd_thread_switch(next); tls_thread_switch(next); hw_breakpoint_thread_switch(next); diff --git a/arch/arm64/lib/copy_from_user.S b/arch/arm64/lib/copy_from_user.S index dfc33ce09e72..94290069d97d 100644 --- a/arch/arm64/lib/copy_from_user.S +++ b/arch/arm64/lib/copy_from_user.S @@ -63,6 +63,24 @@ SYM_FUNC_START(__arch_copy_from_user) SYM_FUNC_END(__arch_copy_from_user) EXPORT_SYMBOL(__arch_copy_from_user) +#ifdef CONFIG_USE_VECTORIZED_COPY + .macro ldsve reg1, reg2, reg3, reg4, ptr + USER(9997f, ld1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + + .macro stsve reg1, reg2, reg3, reg4, ptr + USER_MC(9998f, st1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + +SYM_FUNC_START(__arch_copy_from_user_fpsimd) + add end, x0, x2 + mov srcin, x1 +#include "copy_template_fpsimd.S" + mov x0, #0 // Nothing to copy + ret +SYM_FUNC_END(__arch_copy_from_user_fpsimd) +EXPORT_SYMBOL(__arch_copy_from_user_fpsimd) +#endif .section .fixup,"ax" .align 2 9997: cmp dst, dstin diff --git a/arch/arm64/lib/copy_in_user.S b/arch/arm64/lib/copy_in_user.S index dbea3799c3ef..cbc09c377050 100644 --- a/arch/arm64/lib/copy_in_user.S +++ b/arch/arm64/lib/copy_in_user.S @@ -64,6 +64,25 @@ SYM_FUNC_START(__arch_copy_in_user) SYM_FUNC_END(__arch_copy_in_user) EXPORT_SYMBOL(__arch_copy_in_user) +#ifdef CONFIG_USE_VECTORIZED_COPY + .macro ldsve reg1, reg2, reg3, reg4, ptr + USER(9997f, ld1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + + .macro stsve reg1, reg2, reg3, reg4, ptr + USER(9997f, st1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + +SYM_FUNC_START(__arch_copy_in_user_fpsimd) + add end, x0, x2 + mov srcin, x1 +#include "copy_template_fpsimd.S" + mov x0, #0 + ret +SYM_FUNC_END(__arch_copy_in_user_fpsimd) +EXPORT_SYMBOL(__arch_copy_in_user_fpsimd) +#endif + .section .fixup,"ax" .align 2 9997: cmp dst, dstin diff --git a/arch/arm64/lib/copy_template_fpsimd.S b/arch/arm64/lib/copy_template_fpsimd.S new file mode 100644 index 000000000000..9b2e7ce1e4d2 --- /dev/null +++ b/arch/arm64/lib/copy_template_fpsimd.S @@ -0,0 +1,180 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2013 ARM Ltd. + * Copyright (C) 2013 Linaro. + * + * This code is based on glibc cortex strings work originally authored by Linaro + * be found @ + * + * http://bazaar.launchpad.net/~linaro-toolchain-dev/cortex-strings/trunk/ + * files/head:/src/aarch64/ + */ + +/* + * Copy a buffer from src to dest (alignment handled by the hardware) + * + * Parameters: + * x0 - dest + * x1 - src + * x2 - n + * Returns: + * x0 - dest + */ +dstin .req x0 +src .req x1 +count .req x2 +tmp1 .req x3 +tmp1w .req w3 +tmp2 .req x4 +tmp2w .req w4 +dst .req x6 + +A_l .req x7 +A_h .req x8 +B_l .req x9 +B_h .req x10 +C_l .req x11 +C_h .req x12 +D_l .req x13 +D_h .req x14 + +V_a .req v20 +V_b .req v21 +V_c .req v22 +V_d .req v23 + + mov dst, dstin + cmp count, #16 + /*When memory length is less than 16, the accessed are not aligned.*/ + b.lo .Ltiny15_fpsimd + + neg tmp2, src + ands tmp2, tmp2, #15/* Bytes to reach alignment. */ + b.eq .LSrcAligned_fpsimd + sub count, count, tmp2 + /* + * Copy the leading memory data from src to dst in an increasing + * address order.By this way,the risk of overwriting the source + * memory data is eliminated when the distance between src and + * dst is less than 16. The memory accesses here are alignment. + */ + tbz tmp2, #0, 1f + ldrb1 tmp1w, src, #1 + strb1 tmp1w, dst, #1 +1: + tbz tmp2, #1, 2f + ldrh1 tmp1w, src, #2 + strh1 tmp1w, dst, #2 +2: + tbz tmp2, #2, 3f + ldr1 tmp1w, src, #4 + str1 tmp1w, dst, #4 +3: + tbz tmp2, #3, .LSrcAligned_fpsimd + ldr1 tmp1, src, #8 + str1 tmp1, dst, #8 + +.LSrcAligned_fpsimd: + cmp count, #64 + b.ge .Lcpy_over64_fpsimd + /* + * Deal with small copies quickly by dropping straight into the + * exit block. + */ +.Ltail63_fpsimd: + /* + * Copy up to 48 bytes of data. At this point we only need the + * bottom 6 bits of count to be accurate. + */ + ands tmp1, count, #0x30 + b.eq .Ltiny15_fpsimd + cmp tmp1w, #0x20 + b.eq 1f + b.lt 2f + ldp1 A_l, A_h, src, #16 + stp1 A_l, A_h, dst, #16 +1: + ldp1 A_l, A_h, src, #16 + stp1 A_l, A_h, dst, #16 +2: + ldp1 A_l, A_h, src, #16 + stp1 A_l, A_h, dst, #16 +.Ltiny15_fpsimd: + /* + * Prefer to break one ldp/stp into several load/store to access + * memory in an increasing address order,rather than to load/store 16 + * bytes from (src-16) to (dst-16) and to backward the src to aligned + * address,which way is used in original cortex memcpy. If keeping + * the original memcpy process here, memmove need to satisfy the + * precondition that src address is at least 16 bytes bigger than dst + * address,otherwise some source data will be overwritten when memove + * call memcpy directly. To make memmove simpler and decouple the + * memcpy's dependency on memmove, withdrew the original process. + */ + tbz count, #3, 1f + ldr1 tmp1, src, #8 + str1 tmp1, dst, #8 +1: + tbz count, #2, 2f + ldr1 tmp1w, src, #4 + str1 tmp1w, dst, #4 +2: + tbz count, #1, 3f + ldrh1 tmp1w, src, #2 + strh1 tmp1w, dst, #2 +3: + tbz count, #0, .Lexitfunc_fpsimd + ldrb1 tmp1w, src, #1 + strb1 tmp1w, dst, #1 + + b .Lexitfunc_fpsimd + +.Lcpy_over64_fpsimd: + subs count, count, #128 + b.ge .Lcpy_body_large_fpsimd + /* + * Less than 128 bytes to copy, so handle 64 here and then jump + * to the tail. + */ + ldp1 A_l, A_h, src, #16 + stp1 A_l, A_h, dst, #16 + ldp1 B_l, B_h, src, #16 + ldp1 C_l, C_h, src, #16 + stp1 B_l, B_h, dst, #16 + stp1 C_l, C_h, dst, #16 + ldp1 D_l, D_h, src, #16 + stp1 D_l, D_h, dst, #16 + + tst count, #0x3f + b.ne .Ltail63_fpsimd + b .Lexitfunc_fpsimd + + /* + * Critical loop. Start at a new cache line boundary. Assuming + * 64 bytes per line this ensures the entire loop is in one line. + */ + .p2align L1_CACHE_SHIFT +.Lcpy_body_large_fpsimd: + /* pre-get 64 bytes data. */ + ldsve V_a.16b, V_b.16b, V_c.16b, V_d.16b, src + add src, src, #64 + +1: + /* + * interlace the load of next 64 bytes data block with store of the last + * loaded 64 bytes data. + */ + stsve V_a.16b, V_b.16b, V_c.16b, V_d.16b, dst + ldsve V_a.16b, V_b.16b, V_c.16b, V_d.16b, src + add dst, dst, #64 + add src, src, #64 + + subs count, count, #64 + b.ge 1b + + stsve V_a.16b, V_b.16b, V_c.16b, V_d.16b, dst + add dst, dst, #64 + + tst count, #0x3f + b.ne .Ltail63_fpsimd +.Lexitfunc_fpsimd: diff --git a/arch/arm64/lib/copy_to_user.S b/arch/arm64/lib/copy_to_user.S index 34154e7c8577..d0211fce4923 100644 --- a/arch/arm64/lib/copy_to_user.S +++ b/arch/arm64/lib/copy_to_user.S @@ -62,6 +62,25 @@ SYM_FUNC_START(__arch_copy_to_user) SYM_FUNC_END(__arch_copy_to_user) EXPORT_SYMBOL(__arch_copy_to_user) +#ifdef CONFIG_USE_VECTORIZED_COPY + .macro stsve reg1, reg2, reg3, reg4, ptr + USER(9997f, st1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + + .macro ldsve reg1, reg2, reg3, reg4, ptr + USER_MC(9998f, ld1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + +SYM_FUNC_START(__arch_copy_to_user_fpsimd) + add end, x0, x2 + mov srcin, x1 +#include "copy_template_fpsimd.S" + mov x0, #0 + ret +SYM_FUNC_END(__arch_copy_to_user_fpsimd) +EXPORT_SYMBOL(__arch_copy_to_user_fpsimd) +#endif + .section .fixup,"ax" .align 2 9997: cmp dst, dstin diff --git a/kernel/softirq.c b/kernel/softirq.c index 9fc69e6e2c11..e3f73422829d 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -26,6 +26,10 @@ #include <linux/tick.h> #include <linux/irq.h> +#ifdef CONFIG_USE_VECTORIZED_COPY +#include <asm/fpsimd.h> +#endif + #define CREATE_TRACE_POINTS #include <trace/events/irq.h> @@ -262,6 +266,9 @@ asmlinkage __visible void __softirq_entry __do_softirq(void) __u32 pending; int softirq_bit; +#ifdef CONFIG_USE_VECTORIZED_COPY + struct fpsimd_state state; +#endif /* * Mask out PF_MEMALLOC as the current task context is borrowed for the * softirq. A softirq handled, such as network RX, might set PF_MEMALLOC @@ -273,8 +280,11 @@ asmlinkage __visible void __softirq_entry __do_softirq(void) account_irq_enter_time(current); __local_bh_disable_ip(_RET_IP_, SOFTIRQ_OFFSET); +#ifdef CONFIG_USE_VECTORIZED_COPY + _kernel_fpsimd_save(&state); + uaccess_priviliged_state_save(); +#endif in_hardirq = lockdep_softirq_start(); - restart: /* Reset the pending bitmask before enabling irqs */ set_softirq_pending(0); @@ -322,6 +332,11 @@ asmlinkage __visible void __softirq_entry __do_softirq(void) lockdep_softirq_end(in_hardirq); account_irq_exit_time(current); + +#ifdef CONFIG_USE_VECTORIZED_COPY + uaccess_priviliged_state_restore(); + _kernel_fpsimd_load(&state); +#endif __local_bh_enable(SOFTIRQ_OFFSET); WARN_ON_ONCE(in_interrupt()); current_restore_flags(old_flags, PF_MEMALLOC); @@ -612,12 +627,21 @@ static void tasklet_action_common(struct softirq_action *a, { struct tasklet_struct *list; +#ifdef CONFIG_USE_VECTORIZED_COPY + struct fpsimd_state state; +#endif + local_irq_disable(); list = tl_head->head; tl_head->head = NULL; tl_head->tail = &tl_head->head; local_irq_enable(); +#ifdef CONFIG_USE_VECTORIZED_COPY + _kernel_fpsimd_save(&state); + uaccess_priviliged_state_save(); +#endif + while (list) { struct tasklet_struct *t = list; @@ -645,6 +669,11 @@ static void tasklet_action_common(struct softirq_action *a, __raise_softirq_irqoff(softirq_nr); local_irq_enable(); } + +#ifdef CONFIG_USE_VECTORIZED_COPY + uaccess_priviliged_state_restore(); + _kernel_fpsimd_load(&state); +#endif } static __latent_entropy void tasklet_action(struct softirq_action *a) diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 0b1c13a05332..9ec07294429b 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -210,6 +210,17 @@ static int max_extfrag_threshold = 1000; #endif /* CONFIG_SYSCTL */ +#ifdef CONFIG_USE_VECTORIZED_COPY +int sysctl_copy_to_user_threshold = -1; +EXPORT_SYMBOL(sysctl_copy_to_user_threshold); + +int sysctl_copy_from_user_threshold = -1; +EXPORT_SYMBOL(sysctl_copy_from_user_threshold); + +int sysctl_copy_in_user_threshold = -1; +EXPORT_SYMBOL(sysctl_copy_in_user_threshold); +#endif + #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_SYSCTL) static int bpf_stats_handler(struct ctl_table *table, int write, void *buffer, size_t *lenp, loff_t *ppos) @@ -3385,6 +3396,30 @@ static struct ctl_table vm_table[] = { .extra2 = SYSCTL_ONE, }, #endif + +#ifdef CONFIG_USE_VECTORIZED_COPY + { + .procname = "copy_to_user_threshold", + .data = &sysctl_copy_to_user_threshold, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec + }, + { + .procname = "copy_from_user_threshold", + .data = &sysctl_copy_from_user_threshold, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec + }, + { + .procname = "copy_in_user_threshold", + .data = &sysctl_copy_in_user_threshold, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec + }, +#endif { } }; -- 2.34.1

2 1

[PATCH v1 OLK-5.10] Add copy to/from/in user with vectorization support
by Nikita Panov 28 Jan '26

28 Jan '26

From: Artem Kuzin <artem.kuzin(a)huawei.com> kunpeng inclusion category: feature bugzilla: https://atomgit.com/openeuler/kernel/issues/8445 ------------------------------------------------- 1. This implementation uses st1/ld1 4-vector instructions which allow to copy 64 bytes at once 2. Copy code is used only if size of data block to copy is more than 128 bytes 4. To use this functionality you need to set configuration switch CONFIG_USE_VECTORIZED_COPY=y 5. Code can be used on any ARMv8 variant 6. In kernel copy functions like memcpy are not supported now, but can be enabled in future 7. For now we use lightweght version of register context saving/restoration (4-registers) We introduce support of vectorization for copy_from/to/in_user functions. Nowadays it works in parallel with original FPSIMD/SVE vectorization and doesn't affect it anyhow. We have special flag in task struct - TIF_KERNEL_FPSIMD, that set if currently we use lightweight vectorization in kernel. Task struct has been updated by two fields: user space fpsimd state and kernel fpsimd state. User space fpsimd state used by kernel_fpsimd_begin(), kernel_fpsimd_end() functions that wrap lightweight FPSIMD contexts usage in kernel space. Kernel fpsimd state is used to manage threads switch. Now there is no support of nested calls of kernel_neon_begin()/kernel_fpsimd_begin() and there is no plans to support this in future. This is not necessary. We save lightweight FPSIMD context in kernel_fpsimd_begin(), and restore it in /kernel_fpsimd_end(). On thread switch we preserve kernel FPSIMD context and restore user space one if any. This prevens curruption of user space FPSIMD state. Before switching to the next thread we restore it's kernel FPSIMD context if any. It is allowed to use FPSIMD in bottom halves, due to in case of BH preemption we check TIF_KERNEL_FPSIMD flag and save/restore contexts. Context management if quite lightweight and executed only in case of TIF_KERNEL_FPSIMD flag is set. To enable this feature, you need to manually modify one of the appropriate entries: /proc/sys/vm/copy_from_user_threshold /proc/sys/vm/copy_in_user_threshold /proc/sys/vm/copy_to_user_threshold Allowed values are following: -1 - feature enabled 0 - feature always enabled n (n >0) - feature enabled, if copied size is greater than n KB. P.S.: What I am personally don't like in current approach: 1. Additional fields and flag in task struct look quite ugly 2. No way to configure the size of chunk to copy using FPSIMD from user space 3. FPSIMD-based memory movement is not generic, need to enable for memmove(), memcpy() and friends in future. Co-developed-by: Alexander Kozhevnikov <alexander.kozhevnikov(a)huawei-partners.com> Signed-off-by: Alexander Kozhevnikov <alexander.kozhevnikov(a)huawei-partners.com> Co-developed-by: Nikita Panov <panov.nikita(a)huawei.com> Signed-off-by: Nikita Panov <panov.nikita(a)huawei.com> Signed-off-by: Artem Kuzin <artem.kuzin(a)huawei.com> --- arch/arm64/Kconfig | 15 ++ arch/arm64/include/asm/fpsimd.h | 15 ++ arch/arm64/include/asm/fpsimdmacros.h | 14 ++ arch/arm64/include/asm/neon.h | 28 +++ arch/arm64/include/asm/processor.h | 7 + arch/arm64/include/asm/thread_info.h | 4 + arch/arm64/include/asm/uaccess.h | 271 +++++++++++++++++++++++++- arch/arm64/kernel/entry-fpsimd.S | 22 +++ arch/arm64/kernel/fpsimd.c | 102 +++++++++- arch/arm64/kernel/process.c | 2 +- arch/arm64/lib/copy_from_user.S | 18 ++ arch/arm64/lib/copy_in_user.S | 19 ++ arch/arm64/lib/copy_template_fpsimd.S | 180 +++++++++++++++++ arch/arm64/lib/copy_to_user.S | 19 ++ kernel/softirq.c | 31 ++- kernel/sysctl.c | 35 ++++ 16 files changed, 774 insertions(+), 8 deletions(-) create mode 100644 arch/arm64/lib/copy_template_fpsimd.S diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index eb30ef59aca2..959af31f7e70 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -1470,6 +1470,21 @@ config ARM64_ILP32 is an ABI where long and pointers are 32bits but it uses the AARCH64 instruction set. +config USE_VECTORIZED_COPY + bool "Use vectorized instructions in copy_to/from user" + depends on KERNEL_MODE_NEON + default y + help + This option turns on vectorization to speed up copy_to/from_user routines. + +config VECTORIZED_COPY_VALIDATE + bool "Validate result of vectorized copy using regular implementation" + depends on KERNEL_MODE_NEON + depends on USE_VECTORIZED_COPY + default n + help + This option turns on vectorization to speed up copy_to/from_user routines. + menuconfig AARCH32_EL0 bool "Kernel support for 32-bit EL0" depends on ARM64_4K_PAGES || EXPERT diff --git a/arch/arm64/include/asm/fpsimd.h b/arch/arm64/include/asm/fpsimd.h index 22f6c6e23441..cb53767105ef 100644 --- a/arch/arm64/include/asm/fpsimd.h +++ b/arch/arm64/include/asm/fpsimd.h @@ -46,6 +46,21 @@ struct task_struct; +#ifdef CONFIG_USE_VECTORIZED_COPY +extern void fpsimd_save_state_light(struct fpsimd_state *state); +extern void fpsimd_load_state_light(struct fpsimd_state *state); +#else +static inline void fpsimd_save_state_light(struct fpsimd_state *state) +{ + (void) state; +} + +static inline void fpsimd_load_state_light(struct fpsimd_state *state) +{ + (void) state; +} +#endif + extern void fpsimd_save_state(struct user_fpsimd_state *state); extern void fpsimd_load_state(struct user_fpsimd_state *state); diff --git a/arch/arm64/include/asm/fpsimdmacros.h b/arch/arm64/include/asm/fpsimdmacros.h index ea2577e159f6..62f5f8a0540a 100644 --- a/arch/arm64/include/asm/fpsimdmacros.h +++ b/arch/arm64/include/asm/fpsimdmacros.h @@ -8,6 +8,20 @@ #include <asm/assembler.h> +#ifdef CONFIG_USE_VECTORIZED_COPY +/* Lightweight fpsimd context saving/restoration. + * Necessary for vectorized kernel memory movement + * implementation + */ +.macro fpsimd_save_light state + st1 {v20.16b, v21.16b, v22.16b, v23.16b}, [\state] +.endm + +.macro fpsimd_restore_light state + ld1 {v20.16b, v21.16b, v22.16b, v23.16b}, [\state] +.endm +#endif + .macro fpsimd_save state, tmpnr stp q0, q1, [\state, #16 * 0] stp q2, q3, [\state, #16 * 2] diff --git a/arch/arm64/include/asm/neon.h b/arch/arm64/include/asm/neon.h index d4b1d172a79b..ab84b194d7b3 100644 --- a/arch/arm64/include/asm/neon.h +++ b/arch/arm64/include/asm/neon.h @@ -16,4 +16,32 @@ void kernel_neon_begin(void); void kernel_neon_end(void); +#ifdef CONFIG_USE_VECTORIZED_COPY +bool kernel_fpsimd_begin(void); +void kernel_fpsimd_end(void); +/* Functions to use in non-preemptible context */ +void _kernel_fpsimd_save(struct fpsimd_state *state); +void _kernel_fpsimd_load(struct fpsimd_state *state); +#else +bool kernel_fpsimd_begin(void) +{ + return false; +} + +void kernel_fpsimd_end(void) +{ +} + +/* Functions to use in non-preemptible context */ +void _kernel_fpsimd_save(struct fpsimd_state *state) +{ + (void) state; +} + +void _kernel_fpsimd_load(struct fpsimd_state *state) +{ + (void) state; +} +#endif + #endif /* ! __ASM_NEON_H */ diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h index 66186f3ab550..3f6784867508 100644 --- a/arch/arm64/include/asm/processor.h +++ b/arch/arm64/include/asm/processor.h @@ -137,6 +137,10 @@ struct cpu_context { unsigned long pc; }; +struct fpsimd_state { + __uint128_t v[4]; +}; + struct thread_struct { struct cpu_context cpu_context; /* cpu context */ @@ -166,6 +170,9 @@ struct thread_struct { u64 sctlr_tcf0; u64 gcr_user_incl; #endif + struct fpsimd_state ustate; + struct fpsimd_state kstate; + KABI_USE(1, unsigned int vl[ARM64_VEC_MAX]) KABI_USE(2, unsigned int vl_onexec[ARM64_VEC_MAX]) KABI_USE(3, u64 tpidr2_el0) diff --git a/arch/arm64/include/asm/thread_info.h b/arch/arm64/include/asm/thread_info.h index 390d9612546b..2e395ebcc856 100644 --- a/arch/arm64/include/asm/thread_info.h +++ b/arch/arm64/include/asm/thread_info.h @@ -89,6 +89,8 @@ void arch_release_task_struct(struct task_struct *tsk); #define TIF_PATCH_PENDING 28 /* pending live patching update */ #define TIF_SME 29 /* SME in use */ #define TIF_SME_VL_INHERIT 30 /* Inherit SME vl_onexec across exec */ +#define TIF_KERNEL_FPSIMD 31 /* Use FPSIMD in kernel */ +#define TIF_PRIV_UACC_ENABLED 32 /* Whether priviliged uaccess was manually enabled */ #define _TIF_SIGPENDING (1 << TIF_SIGPENDING) #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) @@ -108,6 +110,8 @@ void arch_release_task_struct(struct task_struct *tsk); #define _TIF_32BIT_AARCH64 (1 << TIF_32BIT_AARCH64) #define _TIF_PATCH_PENDING (1 << TIF_PATCH_PENDING) #define _TIF_POLLING_NRFLAG (1 << TIF_POLLING_NRFLAG) +#define _TIF_KERNEL_FPSIMD (1 << TIF_KERNEL_FPSIMD) +#define _TIF_PRIV_UACC_ENABLED (1 << TIF_PRIV_UACC_ENABLED) #define _TIF_WORK_MASK (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \ _TIF_NOTIFY_RESUME | _TIF_FOREIGN_FPSTATE | \ diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h index 03c2db710f92..60ffb6aee7bf 100644 --- a/arch/arm64/include/asm/uaccess.h +++ b/arch/arm64/include/asm/uaccess.h @@ -23,6 +23,7 @@ #include <asm/ptrace.h> #include <asm/memory.h> #include <asm/extable.h> +#include <asm/neon.h> #define HAVE_GET_KERNEL_NOFAULT @@ -174,7 +175,7 @@ static inline void __uaccess_enable_hw_pan(void) CONFIG_ARM64_PAN)); } -static inline void uaccess_disable_privileged(void) +static inline void __uaccess_disable_privileged(void) { if (uaccess_ttbr0_disable()) return; @@ -182,7 +183,22 @@ static inline void uaccess_disable_privileged(void) __uaccess_enable_hw_pan(); } -static inline void uaccess_enable_privileged(void) +static inline void uaccess_disable_privileged(void) +{ + preempt_disable(); + + if (!test_and_clear_thread_flag(TIF_PRIV_UACC_ENABLED)) { + WARN_ON(1); + preempt_enable(); + return; + } + + __uaccess_disable_privileged(); + + preempt_enable(); +} + +static inline void __uaccess_enable_privileged(void) { if (uaccess_ttbr0_enable()) return; @@ -190,6 +206,47 @@ static inline void uaccess_enable_privileged(void) __uaccess_disable_hw_pan(); } +static inline void uaccess_enable_privileged(void) +{ + preempt_disable(); + + if (test_and_set_thread_flag(TIF_PRIV_UACC_ENABLED)) { + WARN_ON(1); + preempt_enable(); + return; + } + + __uaccess_enable_privileged(); + + preempt_enable(); +} + +static inline void uaccess_priviliged_context_switch(struct task_struct *next) +{ + bool curr_enabled = !!test_thread_flag(TIF_PRIV_UACC_ENABLED); + bool next_enabled = !!test_ti_thread_flag(&next->thread_info, TIF_PRIV_UACC_ENABLED); + + if (curr_enabled == next_enabled) + return; + + if (curr_enabled) + __uaccess_disable_privileged(); + else + __uaccess_enable_privileged(); +} + +static inline void uaccess_priviliged_state_save(void) +{ + if (test_thread_flag(TIF_PRIV_UACC_ENABLED)) + __uaccess_disable_privileged(); +} + +static inline void uaccess_priviliged_state_restore(void) +{ + if (test_thread_flag(TIF_PRIV_UACC_ENABLED)) + __uaccess_enable_privileged(); +} + /* * Sanitise a uaccess pointer such that it becomes NULL if above the maximum * user address. In case the pointer is tagged (has the top byte set), untag @@ -386,7 +443,97 @@ do { \ goto err_label; \ } while(0) -extern unsigned long __must_check __arch_copy_from_user(void *to, const void __user *from, unsigned long n); +#define USER_COPY_CHUNK_SIZE 4096 + +#ifdef CONFIG_USE_VECTORIZED_COPY + +extern int sysctl_copy_from_user_threshold; + +#define verify_fpsimd_copy(to, from, n, ret) \ +({ \ + unsigned long __verify_ret = 0; \ + __verify_ret = memcmp(to, from, ret ? n - ret : n); \ + if (__verify_ret) \ + pr_err("FPSIMD:%s inconsistent state\n", __func__); \ + if (ret) \ + pr_err("FPSIMD:%s failed to copy data, expected=%lu, copied=%lu\n", __func__, n, n - ret); \ + __verify_ret |= ret; \ + __verify_ret; \ +}) + +#define compare_fpsimd_copy(to, from, n, ret_fpsimd, ret) \ +({ \ + unsigned long __verify_ret = 0; \ + __verify_ret = memcmp(to, from, ret ? n - ret : n); \ + if (__verify_ret) \ + pr_err("FIXUP:%s inconsistent state\n", __func__); \ + if (ret) \ + pr_err("FIXUP:%s failed to copy data, expected=%lu, copied=%lu\n", __func__, n, n - ret); \ + __verify_ret |= ret; \ + if (ret_fpsimd != ret) { \ + pr_err("FIXUP:%s difference between FPSIMD %lu and regular %lu\n", __func__, n - ret_fpsimd, n - ret); \ + __verify_ret |= 1; \ + } else { \ + __verify_ret = 0; \ + } \ + __verify_ret; \ +}) + +extern unsigned long __must_check +__arch_copy_from_user(void *to, const void __user *from, unsigned long n); + +extern unsigned long __must_check +__arch_copy_from_user_fpsimd(void *to, const void __user *from, unsigned long n); + +static __always_inline unsigned long __must_check +raw_copy_from_user(void *to, const void __user *from, unsigned long n) +{ + unsigned long __acfu_ret; + + if (sysctl_copy_from_user_threshold == -1 || n < sysctl_copy_from_user_threshold) { + uaccess_ttbr0_enable(); + __acfu_ret = __arch_copy_from_user(to, + __uaccess_mask_ptr(from), n); + uaccess_ttbr0_disable(); + } else { + if (kernel_fpsimd_begin()) { + unsigned long __acfu_ret_fpsimd; + + uaccess_enable_privileged(); + __acfu_ret_fpsimd = __arch_copy_from_user_fpsimd((to), + __uaccess_mask_ptr(from), n); + uaccess_disable_privileged(); + + __acfu_ret = __acfu_ret_fpsimd; + kernel_fpsimd_end(); +#ifdef CONFIG_VECTORIZED_COPY_VALIDATE + if (verify_fpsimd_copy(to, __uaccess_mask_ptr(from), n, + __acfu_ret)) { + + uaccess_ttbr0_enable(); + __acfu_ret = __arch_copy_from_user((to), + __uaccess_mask_ptr(from), n); + uaccess_ttbr0_disable(); + + compare_fpsimd_copy(to, __uaccess_mask_ptr(from), n, + __acfu_ret_fpsimd, __acfu_ret); + } +#endif + } else { + uaccess_ttbr0_enable(); + __acfu_ret = __arch_copy_from_user((to), + __uaccess_mask_ptr(from), n); + uaccess_ttbr0_disable(); + } + } + + + return __acfu_ret; +} +#else +extern unsigned long __must_check +__arch_copy_from_user(void *to, const void __user *from, unsigned long n); + #define raw_copy_from_user(to, from, n) \ ({ \ unsigned long __acfu_ret; \ @@ -397,7 +544,66 @@ extern unsigned long __must_check __arch_copy_from_user(void *to, const void __u __acfu_ret; \ }) -extern unsigned long __must_check __arch_copy_to_user(void __user *to, const void *from, unsigned long n); +#endif + +#ifdef CONFIG_USE_VECTORIZED_COPY + +extern int sysctl_copy_to_user_threshold; + +extern unsigned long __must_check +__arch_copy_to_user(void __user *to, const void *from, unsigned long n); + +extern unsigned long __must_check +__arch_copy_to_user_fpsimd(void __user *to, const void *from, unsigned long n); + +static __always_inline unsigned long __must_check +raw_copy_to_user(void __user *to, const void *from, unsigned long n) +{ + unsigned long __actu_ret; + + + if (sysctl_copy_to_user_threshold == -1 || n < sysctl_copy_to_user_threshold) { + uaccess_ttbr0_enable(); + __actu_ret = __arch_copy_to_user(__uaccess_mask_ptr(to), + from, n); + uaccess_ttbr0_disable(); + } else { + if (kernel_fpsimd_begin()) { + unsigned long __actu_ret_fpsimd; + + uaccess_enable_privileged(); + __actu_ret_fpsimd = __arch_copy_to_user_fpsimd(__uaccess_mask_ptr(to), + from, n); + uaccess_disable_privileged(); + + kernel_fpsimd_end(); + __actu_ret = __actu_ret_fpsimd; +#ifdef CONFIG_VECTORIZED_COPY_VALIDATE + if (verify_fpsimd_copy(__uaccess_mask_ptr(to), from, n, + __actu_ret)) { + uaccess_ttbr0_enable(); + __actu_ret = __arch_copy_to_user(__uaccess_mask_ptr(to), + from, n); + uaccess_ttbr0_disable(); + + compare_fpsimd_copy(__uaccess_mask_ptr(to), from, n, + __actu_ret_fpsimd, __actu_ret); + } +#endif + } else { + uaccess_ttbr0_enable(); + __actu_ret = __arch_copy_to_user(__uaccess_mask_ptr(to), + from, n); + uaccess_ttbr0_disable(); + } + } + + return __actu_ret; +} +#else +extern unsigned long __must_check +__arch_copy_to_user(void __user *to, const void *from, unsigned long n); + #define raw_copy_to_user(to, from, n) \ ({ \ unsigned long __actu_ret; \ @@ -407,7 +613,62 @@ extern unsigned long __must_check __arch_copy_to_user(void __user *to, const voi uaccess_ttbr0_disable(); \ __actu_ret; \ }) +#endif +#ifdef CONFIG_USE_VECTORIZED_COPY + +extern int sysctl_copy_in_user_threshold; + +extern unsigned long __must_check +__arch_copy_in_user(void __user *to, const void __user *from, unsigned long n); + +extern unsigned long __must_check +__arch_copy_in_user_fpsimd(void __user *to, const void __user *from, unsigned long n); + +static __always_inline unsigned long __must_check +raw_copy_in_user(void __user *to, const void __user *from, unsigned long n) +{ + unsigned long __aciu_ret; + + if (sysctl_copy_in_user_threshold == -1 || n < sysctl_copy_in_user_threshold) { + uaccess_ttbr0_enable(); + __aciu_ret = __arch_copy_in_user(__uaccess_mask_ptr(to), + __uaccess_mask_ptr(from), n); + uaccess_ttbr0_disable(); + } else { + if (kernel_fpsimd_begin()) { + unsigned long __aciu_ret_fpsimd; + + uaccess_enable_privileged(); + __aciu_ret_fpsimd = __arch_copy_in_user_fpsimd(__uaccess_mask_ptr(to), + __uaccess_mask_ptr(from), n); + uaccess_disable_privileged(); + + kernel_fpsimd_end(); + __aciu_ret = __aciu_ret_fpsimd; +#ifdef CONFIG_VECTORIZED_COPY_VALIDATE + if (verify_fpsimd_copy(__uaccess_mask_ptr(to), __uaccess_mask_ptr(from), n, + __aciu_ret)) { + uaccess_ttbr0_enable(); + __aciu_ret = __arch_copy_in_user(__uaccess_mask_ptr(to), + __uaccess_mask_ptr(from), n); + uaccess_ttbr0_disable(); + + compare_fpsimd_copy(__uaccess_mask_ptr(to), __uaccess_mask_ptr(from), n, + __aciu_ret_fpsimd, __aciu_ret); + } +#endif + } else { + uaccess_ttbr0_enable(); + __aciu_ret = __arch_copy_in_user(__uaccess_mask_ptr(to), + __uaccess_mask_ptr(from), n); + uaccess_ttbr0_disable(); + } + } + + return __aciu_ret; +} +#else extern unsigned long __must_check __arch_copy_in_user(void __user *to, const void __user *from, unsigned long n); #define raw_copy_in_user(to, from, n) \ ({ \ @@ -419,6 +680,8 @@ extern unsigned long __must_check __arch_copy_in_user(void __user *to, const voi __aciu_ret; \ }) +#endif + #define INLINE_COPY_TO_USER #define INLINE_COPY_FROM_USER diff --git a/arch/arm64/kernel/entry-fpsimd.S b/arch/arm64/kernel/entry-fpsimd.S index 8d12aaac7862..848ca6a351d7 100644 --- a/arch/arm64/kernel/entry-fpsimd.S +++ b/arch/arm64/kernel/entry-fpsimd.S @@ -11,6 +11,28 @@ #include <asm/assembler.h> #include <asm/fpsimdmacros.h> +#ifdef CONFIG_USE_VECTORIZED_COPY +/* + * Save the FP registers. + * + * x0 - pointer to struct fpsimd_state_light + */ +SYM_FUNC_START(fpsimd_save_state_light) + fpsimd_save_light x0 + ret +SYM_FUNC_END(fpsimd_save_state_light) + +/* + * Load the FP registers. + * + * x0 - pointer to struct fpsimd_state_light + */ +SYM_FUNC_START(fpsimd_load_state_light) + fpsimd_restore_light x0 + ret +SYM_FUNC_END(fpsimd_load_state_light) +#endif + /* * Save the FP registers. * diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c index c2489a72b0b9..1a08c19a181f 100644 --- a/arch/arm64/kernel/fpsimd.c +++ b/arch/arm64/kernel/fpsimd.c @@ -1492,6 +1492,11 @@ void do_fpsimd_exc(unsigned int esr, struct pt_regs *regs) current); } +#ifdef CONFIG_USE_VECTORIZED_COPY +static void kernel_fpsimd_rollback_changes(void); +static void kernel_fpsimd_restore_changes(struct task_struct *tsk); +#endif + void fpsimd_thread_switch(struct task_struct *next) { bool wrong_task, wrong_cpu; @@ -1500,10 +1505,11 @@ void fpsimd_thread_switch(struct task_struct *next) return; __get_cpu_fpsimd_context(); - +#ifdef CONFIG_USE_VECTORIZED_COPY + kernel_fpsimd_rollback_changes(); +#endif /* Save unsaved fpsimd state, if any: */ fpsimd_save(); - /* * Fix up TIF_FOREIGN_FPSTATE to correctly describe next's * state. For kernel threads, FPSIMD registers are never loaded @@ -1516,6 +1522,9 @@ void fpsimd_thread_switch(struct task_struct *next) update_tsk_thread_flag(next, TIF_FOREIGN_FPSTATE, wrong_task || wrong_cpu); +#ifdef CONFIG_USE_VECTORIZED_COPY + kernel_fpsimd_restore_changes(next); +#endif __put_cpu_fpsimd_context(); } @@ -1835,6 +1844,95 @@ void kernel_neon_end(void) } EXPORT_SYMBOL(kernel_neon_end); +#ifdef CONFIG_USE_VECTORIZED_COPY +bool kernel_fpsimd_begin(void) +{ + if (WARN_ON(!system_capabilities_finalized()) || + !system_supports_fpsimd() || + in_irq() || irqs_disabled() || in_nmi()) + return false; + + preempt_disable(); + if (test_and_set_thread_flag(TIF_KERNEL_FPSIMD)) { + preempt_enable(); + + WARN_ON(1); + return false; + } + + /* + * Leaving streaming mode enabled will cause issues for any kernel + * NEON and leaving streaming mode or ZA enabled may increase power + * consumption. + */ + if (system_supports_sme()) + sme_smstop(); + + fpsimd_save_state_light(&current->thread.ustate); + preempt_enable(); + + return true; +} +EXPORT_SYMBOL(kernel_fpsimd_begin); + +void kernel_fpsimd_end(void) +{ + if (!system_supports_fpsimd()) + return; + + preempt_disable(); + if (test_and_clear_thread_flag(TIF_KERNEL_FPSIMD)) + fpsimd_load_state_light(&current->thread.ustate); + + preempt_enable(); +} +EXPORT_SYMBOL(kernel_fpsimd_end); + +void _kernel_fpsimd_save(struct fpsimd_state *state) +{ + if (!system_supports_fpsimd()) + return; + + BUG_ON(preemptible()); + if (test_thread_flag(TIF_KERNEL_FPSIMD)) + fpsimd_save_state_light(state); +} + +void _kernel_fpsimd_load(struct fpsimd_state *state) +{ + if (!system_supports_fpsimd()) + return; + + BUG_ON(preemptible()); + if (test_thread_flag(TIF_KERNEL_FPSIMD)) + fpsimd_load_state_light(state); +} + +static void kernel_fpsimd_rollback_changes(void) +{ + if (!system_supports_fpsimd()) + return; + + BUG_ON(preemptible()); + if (test_thread_flag(TIF_KERNEL_FPSIMD)) { + fpsimd_save_state_light(&current->thread.kstate); + fpsimd_load_state_light(&current->thread.ustate); + } +} + +static void kernel_fpsimd_restore_changes(struct task_struct *tsk) +{ + if (!system_supports_fpsimd()) + return; + + BUG_ON(preemptible()); + if (test_ti_thread_flag(task_thread_info(tsk), TIF_KERNEL_FPSIMD)) { + fpsimd_save_state_light(&tsk->thread.ustate); + fpsimd_load_state_light(&tsk->thread.kstate); + } +} +#endif + #ifdef CONFIG_EFI static DEFINE_PER_CPU(struct user_fpsimd_state, efi_fpsimd_state); diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c index 14300c9e06d5..338d40725a5d 100644 --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -572,7 +572,7 @@ __notrace_funcgraph struct task_struct *__switch_to(struct task_struct *prev, struct task_struct *next) { struct task_struct *last; - + uaccess_priviliged_context_switch(next); fpsimd_thread_switch(next); tls_thread_switch(next); hw_breakpoint_thread_switch(next); diff --git a/arch/arm64/lib/copy_from_user.S b/arch/arm64/lib/copy_from_user.S index dfc33ce09e72..94290069d97d 100644 --- a/arch/arm64/lib/copy_from_user.S +++ b/arch/arm64/lib/copy_from_user.S @@ -63,6 +63,24 @@ SYM_FUNC_START(__arch_copy_from_user) SYM_FUNC_END(__arch_copy_from_user) EXPORT_SYMBOL(__arch_copy_from_user) +#ifdef CONFIG_USE_VECTORIZED_COPY + .macro ldsve reg1, reg2, reg3, reg4, ptr + USER(9997f, ld1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + + .macro stsve reg1, reg2, reg3, reg4, ptr + USER_MC(9998f, st1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + +SYM_FUNC_START(__arch_copy_from_user_fpsimd) + add end, x0, x2 + mov srcin, x1 +#include "copy_template_fpsimd.S" + mov x0, #0 // Nothing to copy + ret +SYM_FUNC_END(__arch_copy_from_user_fpsimd) +EXPORT_SYMBOL(__arch_copy_from_user_fpsimd) +#endif .section .fixup,"ax" .align 2 9997: cmp dst, dstin diff --git a/arch/arm64/lib/copy_in_user.S b/arch/arm64/lib/copy_in_user.S index dbea3799c3ef..cbc09c377050 100644 --- a/arch/arm64/lib/copy_in_user.S +++ b/arch/arm64/lib/copy_in_user.S @@ -64,6 +64,25 @@ SYM_FUNC_START(__arch_copy_in_user) SYM_FUNC_END(__arch_copy_in_user) EXPORT_SYMBOL(__arch_copy_in_user) +#ifdef CONFIG_USE_VECTORIZED_COPY + .macro ldsve reg1, reg2, reg3, reg4, ptr + USER(9997f, ld1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + + .macro stsve reg1, reg2, reg3, reg4, ptr + USER(9997f, st1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + +SYM_FUNC_START(__arch_copy_in_user_fpsimd) + add end, x0, x2 + mov srcin, x1 +#include "copy_template_fpsimd.S" + mov x0, #0 + ret +SYM_FUNC_END(__arch_copy_in_user_fpsimd) +EXPORT_SYMBOL(__arch_copy_in_user_fpsimd) +#endif + .section .fixup,"ax" .align 2 9997: cmp dst, dstin diff --git a/arch/arm64/lib/copy_template_fpsimd.S b/arch/arm64/lib/copy_template_fpsimd.S new file mode 100644 index 000000000000..9b2e7ce1e4d2 --- /dev/null +++ b/arch/arm64/lib/copy_template_fpsimd.S @@ -0,0 +1,180 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2013 ARM Ltd. + * Copyright (C) 2013 Linaro. + * + * This code is based on glibc cortex strings work originally authored by Linaro + * be found @ + * + * http://bazaar.launchpad.net/~linaro-toolchain-dev/cortex-strings/trunk/ + * files/head:/src/aarch64/ + */ + +/* + * Copy a buffer from src to dest (alignment handled by the hardware) + * + * Parameters: + * x0 - dest + * x1 - src + * x2 - n + * Returns: + * x0 - dest + */ +dstin .req x0 +src .req x1 +count .req x2 +tmp1 .req x3 +tmp1w .req w3 +tmp2 .req x4 +tmp2w .req w4 +dst .req x6 + +A_l .req x7 +A_h .req x8 +B_l .req x9 +B_h .req x10 +C_l .req x11 +C_h .req x12 +D_l .req x13 +D_h .req x14 + +V_a .req v20 +V_b .req v21 +V_c .req v22 +V_d .req v23 + + mov dst, dstin + cmp count, #16 + /*When memory length is less than 16, the accessed are not aligned.*/ + b.lo .Ltiny15_fpsimd + + neg tmp2, src + ands tmp2, tmp2, #15/* Bytes to reach alignment. */ + b.eq .LSrcAligned_fpsimd + sub count, count, tmp2 + /* + * Copy the leading memory data from src to dst in an increasing + * address order.By this way,the risk of overwriting the source + * memory data is eliminated when the distance between src and + * dst is less than 16. The memory accesses here are alignment. + */ + tbz tmp2, #0, 1f + ldrb1 tmp1w, src, #1 + strb1 tmp1w, dst, #1 +1: + tbz tmp2, #1, 2f + ldrh1 tmp1w, src, #2 + strh1 tmp1w, dst, #2 +2: + tbz tmp2, #2, 3f + ldr1 tmp1w, src, #4 + str1 tmp1w, dst, #4 +3: + tbz tmp2, #3, .LSrcAligned_fpsimd + ldr1 tmp1, src, #8 + str1 tmp1, dst, #8 + +.LSrcAligned_fpsimd: + cmp count, #64 + b.ge .Lcpy_over64_fpsimd + /* + * Deal with small copies quickly by dropping straight into the + * exit block. + */ +.Ltail63_fpsimd: + /* + * Copy up to 48 bytes of data. At this point we only need the + * bottom 6 bits of count to be accurate. + */ + ands tmp1, count, #0x30 + b.eq .Ltiny15_fpsimd + cmp tmp1w, #0x20 + b.eq 1f + b.lt 2f + ldp1 A_l, A_h, src, #16 + stp1 A_l, A_h, dst, #16 +1: + ldp1 A_l, A_h, src, #16 + stp1 A_l, A_h, dst, #16 +2: + ldp1 A_l, A_h, src, #16 + stp1 A_l, A_h, dst, #16 +.Ltiny15_fpsimd: + /* + * Prefer to break one ldp/stp into several load/store to access + * memory in an increasing address order,rather than to load/store 16 + * bytes from (src-16) to (dst-16) and to backward the src to aligned + * address,which way is used in original cortex memcpy. If keeping + * the original memcpy process here, memmove need to satisfy the + * precondition that src address is at least 16 bytes bigger than dst + * address,otherwise some source data will be overwritten when memove + * call memcpy directly. To make memmove simpler and decouple the + * memcpy's dependency on memmove, withdrew the original process. + */ + tbz count, #3, 1f + ldr1 tmp1, src, #8 + str1 tmp1, dst, #8 +1: + tbz count, #2, 2f + ldr1 tmp1w, src, #4 + str1 tmp1w, dst, #4 +2: + tbz count, #1, 3f + ldrh1 tmp1w, src, #2 + strh1 tmp1w, dst, #2 +3: + tbz count, #0, .Lexitfunc_fpsimd + ldrb1 tmp1w, src, #1 + strb1 tmp1w, dst, #1 + + b .Lexitfunc_fpsimd + +.Lcpy_over64_fpsimd: + subs count, count, #128 + b.ge .Lcpy_body_large_fpsimd + /* + * Less than 128 bytes to copy, so handle 64 here and then jump + * to the tail. + */ + ldp1 A_l, A_h, src, #16 + stp1 A_l, A_h, dst, #16 + ldp1 B_l, B_h, src, #16 + ldp1 C_l, C_h, src, #16 + stp1 B_l, B_h, dst, #16 + stp1 C_l, C_h, dst, #16 + ldp1 D_l, D_h, src, #16 + stp1 D_l, D_h, dst, #16 + + tst count, #0x3f + b.ne .Ltail63_fpsimd + b .Lexitfunc_fpsimd + + /* + * Critical loop. Start at a new cache line boundary. Assuming + * 64 bytes per line this ensures the entire loop is in one line. + */ + .p2align L1_CACHE_SHIFT +.Lcpy_body_large_fpsimd: + /* pre-get 64 bytes data. */ + ldsve V_a.16b, V_b.16b, V_c.16b, V_d.16b, src + add src, src, #64 + +1: + /* + * interlace the load of next 64 bytes data block with store of the last + * loaded 64 bytes data. + */ + stsve V_a.16b, V_b.16b, V_c.16b, V_d.16b, dst + ldsve V_a.16b, V_b.16b, V_c.16b, V_d.16b, src + add dst, dst, #64 + add src, src, #64 + + subs count, count, #64 + b.ge 1b + + stsve V_a.16b, V_b.16b, V_c.16b, V_d.16b, dst + add dst, dst, #64 + + tst count, #0x3f + b.ne .Ltail63_fpsimd +.Lexitfunc_fpsimd: diff --git a/arch/arm64/lib/copy_to_user.S b/arch/arm64/lib/copy_to_user.S index 34154e7c8577..d0211fce4923 100644 --- a/arch/arm64/lib/copy_to_user.S +++ b/arch/arm64/lib/copy_to_user.S @@ -62,6 +62,25 @@ SYM_FUNC_START(__arch_copy_to_user) SYM_FUNC_END(__arch_copy_to_user) EXPORT_SYMBOL(__arch_copy_to_user) +#ifdef CONFIG_USE_VECTORIZED_COPY + .macro stsve reg1, reg2, reg3, reg4, ptr + USER(9997f, st1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + + .macro ldsve reg1, reg2, reg3, reg4, ptr + USER_MC(9998f, ld1 {\reg1, \reg2, \reg3, \reg4}, [\ptr]) + .endm + +SYM_FUNC_START(__arch_copy_to_user_fpsimd) + add end, x0, x2 + mov srcin, x1 +#include "copy_template_fpsimd.S" + mov x0, #0 + ret +SYM_FUNC_END(__arch_copy_to_user_fpsimd) +EXPORT_SYMBOL(__arch_copy_to_user_fpsimd) +#endif + .section .fixup,"ax" .align 2 9997: cmp dst, dstin diff --git a/kernel/softirq.c b/kernel/softirq.c index 9fc69e6e2c11..e3f73422829d 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -26,6 +26,10 @@ #include <linux/tick.h> #include <linux/irq.h> +#ifdef CONFIG_USE_VECTORIZED_COPY +#include <asm/fpsimd.h> +#endif + #define CREATE_TRACE_POINTS #include <trace/events/irq.h> @@ -262,6 +266,9 @@ asmlinkage __visible void __softirq_entry __do_softirq(void) __u32 pending; int softirq_bit; +#ifdef CONFIG_USE_VECTORIZED_COPY + struct fpsimd_state state; +#endif /* * Mask out PF_MEMALLOC as the current task context is borrowed for the * softirq. A softirq handled, such as network RX, might set PF_MEMALLOC @@ -273,8 +280,11 @@ asmlinkage __visible void __softirq_entry __do_softirq(void) account_irq_enter_time(current); __local_bh_disable_ip(_RET_IP_, SOFTIRQ_OFFSET); +#ifdef CONFIG_USE_VECTORIZED_COPY + _kernel_fpsimd_save(&state); + uaccess_priviliged_state_save(); +#endif in_hardirq = lockdep_softirq_start(); - restart: /* Reset the pending bitmask before enabling irqs */ set_softirq_pending(0); @@ -322,6 +332,11 @@ asmlinkage __visible void __softirq_entry __do_softirq(void) lockdep_softirq_end(in_hardirq); account_irq_exit_time(current); + +#ifdef CONFIG_USE_VECTORIZED_COPY + uaccess_priviliged_state_restore(); + _kernel_fpsimd_load(&state); +#endif __local_bh_enable(SOFTIRQ_OFFSET); WARN_ON_ONCE(in_interrupt()); current_restore_flags(old_flags, PF_MEMALLOC); @@ -612,12 +627,21 @@ static void tasklet_action_common(struct softirq_action *a, { struct tasklet_struct *list; +#ifdef CONFIG_USE_VECTORIZED_COPY + struct fpsimd_state state; +#endif + local_irq_disable(); list = tl_head->head; tl_head->head = NULL; tl_head->tail = &tl_head->head; local_irq_enable(); +#ifdef CONFIG_USE_VECTORIZED_COPY + _kernel_fpsimd_save(&state); + uaccess_priviliged_state_save(); +#endif + while (list) { struct tasklet_struct *t = list; @@ -645,6 +669,11 @@ static void tasklet_action_common(struct softirq_action *a, __raise_softirq_irqoff(softirq_nr); local_irq_enable(); } + +#ifdef CONFIG_USE_VECTORIZED_COPY + uaccess_priviliged_state_restore(); + _kernel_fpsimd_load(&state); +#endif } static __latent_entropy void tasklet_action(struct softirq_action *a) diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 0b1c13a05332..9ec07294429b 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -210,6 +210,17 @@ static int max_extfrag_threshold = 1000; #endif /* CONFIG_SYSCTL */ +#ifdef CONFIG_USE_VECTORIZED_COPY +int sysctl_copy_to_user_threshold = -1; +EXPORT_SYMBOL(sysctl_copy_to_user_threshold); + +int sysctl_copy_from_user_threshold = -1; +EXPORT_SYMBOL(sysctl_copy_from_user_threshold); + +int sysctl_copy_in_user_threshold = -1; +EXPORT_SYMBOL(sysctl_copy_in_user_threshold); +#endif + #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_SYSCTL) static int bpf_stats_handler(struct ctl_table *table, int write, void *buffer, size_t *lenp, loff_t *ppos) @@ -3385,6 +3396,30 @@ static struct ctl_table vm_table[] = { .extra2 = SYSCTL_ONE, }, #endif + +#ifdef CONFIG_USE_VECTORIZED_COPY + { + .procname = "copy_to_user_threshold", + .data = &sysctl_copy_to_user_threshold, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec + }, + { + .procname = "copy_from_user_threshold", + .data = &sysctl_copy_from_user_threshold, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec + }, + { + .procname = "copy_in_user_threshold", + .data = &sysctl_copy_in_user_threshold, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec + }, +#endif { } }; -- 2.34.1

2 1

[PATCH OLK-5.10] ext4: fix e4b bitmap inconsistency reports
by Yongjian Sun 28 Jan '26

28 Jan '26

hulk inclusion category: bugfix bugzilla: https://atomgit.com/openeuler/kernel/issues/8330 ---------------------------------------------------------------------- A bitmap inconsistency issue was observed during stress tests under mixed huge-page workloads. Ext4 reported multiple e4b bitmap check failures like: ext4_mb_complex_scan_group:2508: group 350, 8179 free clusters as per group info. But got 8192 blocks Analysis and experimentation confirmed that the issue is caused by a race condition between page migration and bitmap modification. Although this timing window is extremely narrow, it is still hit in practice: folio_lock ext4_mb_load_buddy __migrate_folio check ref count folio_mc_copy __filemap_get_folio folio_try_get(folio) ...... mb_mark_used ext4_mb_unload_buddy __folio_migrate_mapping folio_ref_freeze folio_unlock The root cause of this issue is that the fast path of load_buddy only increments the folio's reference count, which is insufficient to prevent concurrent folio migration. We observed that the folio migration process acquires the folio lock. Therefore, we can determine whether to take the fast path in load_buddy by checking the lock status. If the folio is locked, we opt for the slow path (which acquires the lock) to close this concurrency window. Additionally, this change addresses the following issues: When the DOUBLE_CHECK macro is enabled to inspect bitmap-related issues, the following error may be triggered: corruption in group 324 at byte 784(6272): f in copy != ff on disk/prealloc Analysis reveals that this is a false positive. There is a specific race window where the bitmap and the group descriptor become momentarily inconsistent, leading to this error report: ext4_mb_load_buddy ext4_mb_load_buddy __filemap_get_folio(create|lock) folio_lock ext4_mb_init_cache folio_mark_uptodate __filemap_get_folio(no lock) ...... mb_mark_used mb_mark_used_double mb_cmp_bitmaps mb_set_bits(e4b->bd_bitmap) folio_unlock The original logic assumed that since mb_cmp_bitmaps is called when the bitmap is newly loaded from disk, the folio lock would be sufficient to prevent concurrent access. However, this overlooks a specific race condition: if another process attempts to load buddy and finds the folio is already in an uptodate state, it will immediately begin using it without holding folio lock. Fixes: 9bb3fd60f91e ("arm64: mm: Add copy mc support for all migrate_page") Signed-off-by: Yongjian Sun <sunyongjian1(a)huawei.com> --- fs/ext4/mballoc.c | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-) diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 522d2ec128ef..9d4e8e3c74e2 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -1217,16 +1217,17 @@ ext4_mb_load_buddy_gfp(struct super_block *sb, ext4_group_t group, /* we could use find_or_create_page(), but it locks page * what we'd like to avoid in fast path ... */ page = find_get_page_flags(inode->i_mapping, pnum, FGP_ACCESSED); - if (page == NULL || !PageUptodate(page)) { + if (page == NULL || !PageUptodate(page) || PageLocked(page)) { + /* + * PageLocked is employed to detect ongoing page + * migrations, since concurrent migrations can lead to + * bitmap inconsistency. And if we are not uptodate that + * implies somebody just created the page but is yet to + * initialize it. We can drop the page reference and + * try to get the page with lock in both cases to avoid + * concurrency. + */ if (page) - /* - * drop the page reference and try - * to get the page with lock. If we - * are not uptodate that implies - * somebody just created the page but - * is yet to initialize the same. So - * wait for it to initialize. - */ put_page(page); page = find_or_create_page(inode->i_mapping, pnum, gfp); if (page) { @@ -1261,7 +1262,7 @@ ext4_mb_load_buddy_gfp(struct super_block *sb, ext4_group_t group, poff = block % blocks_per_page; page = find_get_page_flags(inode->i_mapping, pnum, FGP_ACCESSED); - if (page == NULL || !PageUptodate(page)) { + if (page == NULL || !PageUptodate(page) || PageLocked(page)) { if (page) put_page(page); page = find_or_create_page(inode->i_mapping, pnum, gfp); -- 2.39.2

2 1

[PATCH OLK-6.6] udp: Deal with race between UDP socket address change and rehash
by Zhang Changzhong 28 Jan '26

28 Jan '26

From: Stefano Brivio <sbrivio(a)redhat.com> mainline inclusion from mainline-v6.14-rc1 commit a502ea6fa94b1f7be72a24bcf9e3f5f6b7e6e90c category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/10960 CVE: CVE-2024-57974 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… ------------------------------------------------- If a UDP socket changes its local address while it's receiving datagrams, as a result of connect(), there is a period during which a lookup operation might fail to find it, after the address is changed but before the secondary hash (port and address) and the four-tuple hash (local and remote ports and addresses) are updated. Secondary hash chains were introduced by commit 30fff9231fad ("udp: bind() optimisation") and, as a result, a rehash operation became needed to make a bound socket reachable again after a connect(). This operation was introduced by commit 719f835853a9 ("udp: add rehash on connect()") which isn't however a complete fix: the socket will be found once the rehashing completes, but not while it's pending. This is noticeable with a socat(1) server in UDP4-LISTEN mode, and a client sending datagrams to it. After the server receives the first datagram (cf. _xioopen_ipdgram_listen()), it issues a connect() to the address of the sender, in order to set up a directed flow. Now, if the client, running on a different CPU thread, happens to send a (subsequent) datagram while the server's socket changes its address, but is not rehashed yet, this will result in a failed lookup and a port unreachable error delivered to the client, as apparent from the following reproducer: LEN=$(($(cat /proc/sys/net/core/wmem_default) / 4)) dd if=/dev/urandom bs=1 count=${LEN} of=tmp.in while :; do taskset -c 1 socat UDP4-LISTEN:1337,null-eof OPEN:tmp.out,create,trunc & sleep 0.1 || sleep 1 taskset -c 2 socat OPEN:tmp.in UDP4:localhost:1337,shut-null wait done where the client will eventually get ECONNREFUSED on a write() (typically the second or third one of a given iteration): 2024/11/13 21:28:23 socat[46901] E write(6, 0x556db2e3c000, 8192): Connection refused This issue was first observed as a seldom failure in Podman's tests checking UDP functionality while using pasta(1) to connect the container's network namespace, which leads us to a reproducer with the lookup error resulting in an ICMP packet on a tap device: LOCAL_ADDR="$(ip -j -4 addr show|jq -rM '.[] | .addr_info[0] | select(.scope == "global").local')" while :; do ./pasta --config-net -p pasta.pcap -u 1337 socat UDP4-LISTEN:1337,null-eof OPEN:tmp.out,create,trunc & sleep 0.2 || sleep 1 socat OPEN:tmp.in UDP4:${LOCAL_ADDR}:1337,shut-null wait cmp tmp.in tmp.out done Once this fails: tmp.in tmp.out differ: char 8193, line 29 we can finally have a look at what's going on: $ tshark -r pasta.pcap 1 0.000000 :: ? ff02::16 ICMPv6 110 Multicast Listener Report Message v2 2 0.168690 88.198.0.161 ? 88.198.0.164 UDP 8234 60260 ? 1337 Len=8192 3 0.168767 88.198.0.161 ? 88.198.0.164 UDP 8234 60260 ? 1337 Len=8192 4 0.168806 88.198.0.161 ? 88.198.0.164 UDP 8234 60260 ? 1337 Len=8192 5 0.168827 c6:47:05:8d:dc:04 ? Broadcast ARP 42 Who has 88.198.0.161? Tell 88.198.0.164 6 0.168851 9a:55:9a:55:9a:55 ? c6:47:05:8d:dc:04 ARP 42 88.198.0.161 is at 9a:55:9a:55:9a:55 7 0.168875 88.198.0.161 ? 88.198.0.164 UDP 8234 60260 ? 1337 Len=8192 8 0.168896 88.198.0.164 ? 88.198.0.161 ICMP 590 Destination unreachable (Port unreachable) 9 0.168926 88.198.0.161 ? 88.198.0.164 UDP 8234 60260 ? 1337 Len=8192 10 0.168959 88.198.0.161 ? 88.198.0.164 UDP 8234 60260 ? 1337 Len=8192 11 0.168989 88.198.0.161 ? 88.198.0.164 UDP 4138 60260 ? 1337 Len=4096 12 0.169010 88.198.0.161 ? 88.198.0.164 UDP 42 60260 ? 1337 Len=0 On the third datagram received, the network namespace of the container initiates an ARP lookup to deliver the ICMP message. In another variant of this reproducer, starting the client with: strace -f pasta --config-net -u 1337 socat UDP4-LISTEN:1337,null-eof OPEN:tmp.out,create,trunc 2>strace.log & and connecting to the socat server using a loopback address: socat OPEN:tmp.in UDP4:localhost:1337,shut-null we can more clearly observe a sendmmsg() call failing after the first datagram is delivered: [pid 278012] connect(173, 0x7fff96c95fc0, 16) = 0 [...] [pid 278012] recvmmsg(173, 0x7fff96c96020, 1024, MSG_DONTWAIT, NULL) = -1 EAGAIN (Resource temporarily unavailable) [pid 278012] sendmmsg(173, 0x561c5ad0a720, 1, MSG_NOSIGNAL) = 1 [...] [pid 278012] sendmmsg(173, 0x561c5ad0a720, 1, MSG_NOSIGNAL) = -1 ECONNREFUSED (Connection refused) and, somewhat confusingly, after a connect() on the same socket succeeded. Until commit 4cdeeee9252a ("net: udp: prefer listeners bound to an address"), the race between receive address change and lookup didn't actually cause visible issues, because, once the lookup based on the secondary hash chain failed, we would still attempt a lookup based on the primary hash (destination port only), and find the socket with the outdated secondary hash. That change, however, dropped port-only lookups altogether, as side effect, making the race visible. To fix this, while avoiding the need to make address changes and rehash atomic against lookups, reintroduce primary hash lookups as fallback, if lookups based on four-tuple and secondary hashes fail. To this end, introduce a simplified lookup implementation, which doesn't take care of SO_REUSEPORT groups: if we have one, there are multiple sockets that would match the four-tuple or secondary hash, meaning that we can't run into this race at all. v2: - instead of synchronising lookup operations against address change plus rehash, reintroduce a simplified version of the original primary hash lookup as fallback v1: - fix build with CONFIG_IPV6=n: add ifdef around sk_v6_rcv_saddr usage (Kuniyuki Iwashima) - directly use sk_rcv_saddr for IPv4 receive addresses instead of fetching inet_rcv_saddr (Kuniyuki Iwashima) - move inet_update_saddr() to inet_hashtables.h and use that to set IPv4/IPv6 addresses as suitable (Kuniyuki Iwashima) - rebase onto net-next, update commit message accordingly Reported-by: Ed Santiago <santiago(a)redhat.com> Link: https://github.com/containers/podman/issues/24147 Analysed-by: David Gibson <david(a)gibson.dropbear.id.au> Fixes: 30fff9231fad ("udp: bind() optimisation") Signed-off-by: Stefano Brivio <sbrivio(a)redhat.com> Reviewed-by: Eric Dumazet <edumazet(a)google.com> Reviewed-by: Willem de Bruijn <willemb(a)google.com> Signed-off-by: David S. Miller <davem(a)davemloft.net> Conflicts: net/ipv4/udp.c net/ipv6/udp.c [context conflicts, and fix some discards qualifiers error.] Signed-off-by: Liu Jian <liujian56(a)huawei.com> Signed-off-by: Zhang Changzhong <zhangchangzhong(a)huawei.com> --- net/ipv4/udp.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ net/ipv6/udp.c | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 108 insertions(+) diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 8a34e22..4c1f82f 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -421,6 +421,49 @@ u32 udp_ehashfn(const struct net *net, const __be32 laddr, const __u16 lport, udp_ehash_secret + net_hash_mix(net)); } +/** + * udp4_lib_lookup1() - Simplified lookup using primary hash (destination port) + * @net: Network namespace + * @saddr: Source address, network order + * @sport: Source port, network order + * @daddr: Destination address, network order + * @hnum: Destination port, host order + * @dif: Destination interface index + * @sdif: Destination bridge port index, if relevant + * @udptable: Set of UDP hash tables + * + * Simplified lookup to be used as fallback if no sockets are found due to a + * potential race between (receive) address change, and lookup happening before + * the rehash operation. This function ignores SO_REUSEPORT groups while scoring + * result sockets, because if we have one, we don't need the fallback at all. + * + * Called under rcu_read_lock(). + * + * Return: socket with highest matching score if any, NULL if none + */ +static struct sock *udp4_lib_lookup1(const struct net *net, + __be32 saddr, __be16 sport, + __be32 daddr, unsigned int hnum, + int dif, int sdif, + const struct udp_table *udptable) +{ + unsigned int slot = udp_hashfn(net, hnum, udptable->mask); + struct udp_hslot *hslot = &udptable->hash[slot]; + struct sock *sk, *result = NULL; + int score, badness = 0; + + sk_for_each_rcu(sk, &hslot->head) { + score = compute_score(sk, (struct net *)net, + saddr, sport, daddr, hnum, dif, sdif); + if (score > badness) { + result = sk; + badness = score; + } + } + + return result; +} + /* called with rcu_read_lock() */ static struct sock *udp4_lib_lookup2(struct net *net, __be32 saddr, __be16 sport, @@ -526,6 +569,19 @@ struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr, result = udp4_lib_lookup2(net, saddr, sport, htonl(INADDR_ANY), hnum, dif, sdif, hslot2, skb); + if (!IS_ERR_OR_NULL(result)) + goto done; + + /* Primary hash (destination port) lookup as fallback for this race: + * 1. __ip4_datagram_connect() sets sk_rcv_saddr + * 2. lookup (this function): new sk_rcv_saddr, hashes not updated yet + * 3. rehash operation updating _secondary and four-tuple_ hashes + * The primary hash doesn't need an update after 1., so, thanks to this + * further step, 1. and 3. don't need to be atomic against the lookup. + */ + result = udp4_lib_lookup1(net, saddr, sport, daddr, hnum, dif, sdif, + udptable); + done: if (IS_ERR(result)) return NULL; diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 9ff8e72..7c9f77f 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -162,6 +162,51 @@ static int compute_score(struct sock *sk, struct net *net, return score; } +/** + * udp6_lib_lookup1() - Simplified lookup using primary hash (destination port) + * @net: Network namespace + * @saddr: Source address, network order + * @sport: Source port, network order + * @daddr: Destination address, network order + * @hnum: Destination port, host order + * @dif: Destination interface index + * @sdif: Destination bridge port index, if relevant + * @udptable: Set of UDP hash tables + * + * Simplified lookup to be used as fallback if no sockets are found due to a + * potential race between (receive) address change, and lookup happening before + * the rehash operation. This function ignores SO_REUSEPORT groups while scoring + * result sockets, because if we have one, we don't need the fallback at all. + * + * Called under rcu_read_lock(). + * + * Return: socket with highest matching score if any, NULL if none + */ +static struct sock *udp6_lib_lookup1(const struct net *net, + const struct in6_addr *saddr, __be16 sport, + const struct in6_addr *daddr, + unsigned int hnum, int dif, int sdif, + const struct udp_table *udptable) +{ + unsigned int slot = udp_hashfn(net, hnum, udptable->mask); + struct udp_hslot *hslot = &udptable->hash[slot]; + struct sock *sk, *result = NULL; + int score, badness = 0; + + sk_for_each_rcu(sk, &hslot->head) { + score = compute_score(sk, (struct net *)net, + (struct in6_addr *)saddr, sport, + (struct in6_addr *)daddr, hnum, + dif, sdif); + if (score > badness) { + result = sk; + badness = score; + } + } + + return result; +} + /* called with rcu_read_lock() */ static struct sock *udp6_lib_lookup2(struct net *net, const struct in6_addr *saddr, __be16 sport, @@ -266,6 +311,13 @@ struct sock *__udp6_lib_lookup(struct net *net, result = udp6_lib_lookup2(net, saddr, sport, &in6addr_any, hnum, dif, sdif, hslot2, skb); + if (!IS_ERR_OR_NULL(result)) + goto done; + + /* Cover address change/lookup/rehash race: see __udp4_lib_lookup() */ + result = udp6_lib_lookup1(net, saddr, sport, daddr, hnum, dif, sdif, + udptable); + done: if (IS_ERR(result)) return NULL; -- 2.9.5

2 1

[PATCH OLK-6.6] x86/fpu: Clear XSTATE_BV[i] in guest XSAVE state whenever XFD[i]=1
by Zhang Kunbo 28 Jan '26

28 Jan '26

From: Sean Christopherson <seanjc(a)google.com> stable inclusion from stable-v6.12.67 commit f577508cc8a0adb8b4ebe9480bba7683b6149930 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/13516 CVE: CVE-2026-23005 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- commit b45f721775947a84996deb5c661602254ce25ce6 upstream. When loading guest XSAVE state via KVM_SET_XSAVE, and when updating XFD in response to a guest WRMSR, clear XFD-disabled features in the saved (or to be restored) XSTATE_BV to ensure KVM doesn't attempt to load state for features that are disabled via the guest's XFD. Because the kernel executes XRSTOR with the guest's XFD, saving XSTATE_BV[i]=1 with XFD[i]=1 will cause XRSTOR to #NM and panic the kernel. E.g. if fpu_update_guest_xfd() sets XFD without clearing XSTATE_BV: ------------[ cut here ]------------ WARNING: arch/x86/kernel/traps.c:1524 at exc_device_not_available+0x101/0x110, CPU#29: amx_test/848 Modules linked in: kvm_intel kvm irqbypass CPU: 29 UID: 1000 PID: 848 Comm: amx_test Not tainted 6.19.0-rc2-ffa07f7fd437-x86_amx_nm_xfd_non_init-vm #171 NONE Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 RIP: 0010:exc_device_not_available+0x101/0x110 Call Trace: <TASK> asm_exc_device_not_available+0x1a/0x20 RIP: 0010:restore_fpregs_from_fpstate+0x36/0x90 switch_fpu_return+0x4a/0xb0 kvm_arch_vcpu_ioctl_run+0x1245/0x1e40 [kvm] kvm_vcpu_ioctl+0x2c3/0x8f0 [kvm] __x64_sys_ioctl+0x8f/0xd0 do_syscall_64+0x62/0x940 entry_SYSCALL_64_after_hwframe+0x4b/0x53 </TASK> ---[ end trace 0000000000000000 ]--- This can happen if the guest executes WRMSR(MSR_IA32_XFD) to set XFD[18] = 1, and a host IRQ triggers kernel_fpu_begin() prior to the vmexit handler's call to fpu_update_guest_xfd(). and if userspace stuffs XSTATE_BV[i]=1 via KVM_SET_XSAVE: ------------[ cut here ]------------ WARNING: arch/x86/kernel/traps.c:1524 at exc_device_not_available+0x101/0x110, CPU#14: amx_test/867 Modules linked in: kvm_intel kvm irqbypass CPU: 14 UID: 1000 PID: 867 Comm: amx_test Not tainted 6.19.0-rc2-2dace9faccd6-x86_amx_nm_xfd_non_init-vm #168 NONE Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 RIP: 0010:exc_device_not_available+0x101/0x110 Call Trace: <TASK> asm_exc_device_not_available+0x1a/0x20 RIP: 0010:restore_fpregs_from_fpstate+0x36/0x90 fpu_swap_kvm_fpstate+0x6b/0x120 kvm_load_guest_fpu+0x30/0x80 [kvm] kvm_arch_vcpu_ioctl_run+0x85/0x1e40 [kvm] kvm_vcpu_ioctl+0x2c3/0x8f0 [kvm] __x64_sys_ioctl+0x8f/0xd0 do_syscall_64+0x62/0x940 entry_SYSCALL_64_after_hwframe+0x4b/0x53 </TASK> ---[ end trace 0000000000000000 ]--- The new behavior is consistent with the AMX architecture. Per Intel's SDM, XSAVE saves XSTATE_BV as '0' for components that are disabled via XFD (and non-compacted XSAVE saves the initial configuration of the state component): If XSAVE, XSAVEC, XSAVEOPT, or XSAVES is saving the state component i, the instruction does not generate #NM when XCR0[i] = IA32_XFD[i] = 1; instead, it operates as if XINUSE[i] = 0 (and the state component was in its initial state): it saves bit i of XSTATE_BV field of the XSAVE header as 0; in addition, XSAVE saves the initial configuration of the state component (the other instructions do not save state component i). Alternatively, KVM could always do XRSTOR with XFD=0, e.g. by using a constant XFD based on the set of enabled features when XSAVEing for a struct fpu_guest. However, having XSTATE_BV[i]=1 for XFD-disabled features can only happen in the above interrupt case, or in similar scenarios involving preemption on preemptible kernels, because fpu_swap_kvm_fpstate()'s call to save_fpregs_to_fpstate() saves the outgoing FPU state with the current XFD; and that is (on all but the first WRMSR to XFD) the guest XFD. Therefore, XFD can only go out of sync with XSTATE_BV in the above interrupt case, or in similar scenarios involving preemption on preemptible kernels, and it we can consider it (de facto) part of KVM ABI that KVM_GET_XSAVE returns XSTATE_BV[i]=0 for XFD-disabled features. Reported-by: Paolo Bonzini <pbonzini(a)redhat.com> Cc: stable(a)vger.kernel.org Fixes: 820a6ee944e7 ("kvm: x86: Add emulation for IA32_XFD", 2022-01-14) Signed-off-by: Sean Christopherson <seanjc(a)google.com> [Move clearing of XSTATE_BV from fpu_copy_uabi_to_guest_fpstate to kvm_vcpu_ioctl_x86_set_xsave. - Paolo] Reviewed-by: Binbin Wu <binbin.wu(a)linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini(a)redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Conflicts: arch/x86/kvm/x86.c [Context difference. ] Signed-off-by: Zhang Kunbo <zhangkunbo(a)huawei.com> --- arch/x86/kernel/fpu/core.c | 32 +++++++++++++++++++++++++++++--- arch/x86/kvm/x86.c | 9 +++++++++ 2 files changed, 38 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index 1f0871be9d53..fd53ff26cd42 100644 --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -296,10 +296,29 @@ EXPORT_SYMBOL_GPL(fpu_enable_guest_xfd_features); #ifdef CONFIG_X86_64 void fpu_update_guest_xfd(struct fpu_guest *guest_fpu, u64 xfd) { + struct fpstate *fpstate = guest_fpu->fpstate; + fpregs_lock(); - guest_fpu->fpstate->xfd = xfd; - if (guest_fpu->fpstate->in_use) - xfd_update_state(guest_fpu->fpstate); + + /* + * KVM's guest ABI is that setting XFD[i]=1 *can* immediately revert the + * save state to its initial configuration. Likewise, KVM_GET_XSAVE does + * the same as XSAVE and returns XSTATE_BV[i]=0 whenever XFD[i]=1. + * + * If the guest's FPU state is in hardware, just update XFD: the XSAVE + * in fpu_swap_kvm_fpstate will clear XSTATE_BV[i] whenever XFD[i]=1. + * + * If however the guest's FPU state is NOT resident in hardware, clear + * disabled components in XSTATE_BV now, or a subsequent XRSTOR will + * attempt to load disabled components and generate #NM _in the host_. + */ + if (xfd && test_thread_flag(TIF_NEED_FPU_LOAD)) + fpstate->regs.xsave.header.xfeatures &= ~xfd; + + fpstate->xfd = xfd; + if (fpstate->in_use) + xfd_update_state(fpstate); + fpregs_unlock(); } EXPORT_SYMBOL_GPL(fpu_update_guest_xfd); @@ -407,6 +426,13 @@ int fpu_copy_uabi_to_guest_fpstate(struct fpu_guest *gfpu, const void *buf, if (ustate->xsave.header.xfeatures & ~xcr0) return -EINVAL; + /* + * Disabled features must be in their initial state, otherwise XRSTOR + * causes an exception. + */ + if (WARN_ON_ONCE(ustate->xsave.header.xfeatures & kstate->xfd)) + return -EINVAL; + /* * Nullify @vpkru to preserve its current value if PKRU's bit isn't set * in the header. KVM's odd ABI is to leave PKRU untouched in this diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 2139f728aecc..57fc6916906b 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -5541,9 +5541,18 @@ static void kvm_vcpu_ioctl_x86_get_xsave(struct kvm_vcpu *vcpu, static int kvm_vcpu_ioctl_x86_set_xsave(struct kvm_vcpu *vcpu, struct kvm_xsave *guest_xsave) { + union fpregs_state *xstate = (union fpregs_state *)guest_xsave->region; + if (fpstate_is_confidential(&vcpu->arch.guest_fpu)) return 0; + /* + * For backwards compatibility, do not expect disabled features to be in + * their initial state. XSTATE_BV[i] must still be cleared whenever + * XFD[i]=1, or XRSTOR would cause a #NM. + */ + xstate->xsave.header.xfeatures &= ~vcpu->arch.guest_fpu.fpstate->xfd; + return fpu_copy_uabi_to_guest_fpstate(&vcpu->arch.guest_fpu, guest_xsave->region, kvm_caps.supported_xcr0, -- 2.34.1

2 1

[PATCH OLK-6.6] x86/fpu: Clear XSTATE_BV[i] in guest XSAVE state whenever XFD[i]=1
by Zhang Kunbo 28 Jan '26

28 Jan '26

From: Sean Christopherson <seanjc(a)google.com> stable inclusion from stable-v6.12.67 commit f577508cc8a0adb8b4ebe9480bba7683b6149930 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/13516 CVE: CVE-2026-23005 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- commit b45f721775947a84996deb5c661602254ce25ce6 upstream. When loading guest XSAVE state via KVM_SET_XSAVE, and when updating XFD in response to a guest WRMSR, clear XFD-disabled features in the saved (or to be restored) XSTATE_BV to ensure KVM doesn't attempt to load state for features that are disabled via the guest's XFD. Because the kernel executes XRSTOR with the guest's XFD, saving XSTATE_BV[i]=1 with XFD[i]=1 will cause XRSTOR to #NM and panic the kernel. E.g. if fpu_update_guest_xfd() sets XFD without clearing XSTATE_BV: ------------[ cut here ]------------ WARNING: arch/x86/kernel/traps.c:1524 at exc_device_not_available+0x101/0x110, CPU#29: amx_test/848 Modules linked in: kvm_intel kvm irqbypass CPU: 29 UID: 1000 PID: 848 Comm: amx_test Not tainted 6.19.0-rc2-ffa07f7fd437-x86_amx_nm_xfd_non_init-vm #171 NONE Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 RIP: 0010:exc_device_not_available+0x101/0x110 Call Trace: <TASK> asm_exc_device_not_available+0x1a/0x20 RIP: 0010:restore_fpregs_from_fpstate+0x36/0x90 switch_fpu_return+0x4a/0xb0 kvm_arch_vcpu_ioctl_run+0x1245/0x1e40 [kvm] kvm_vcpu_ioctl+0x2c3/0x8f0 [kvm] __x64_sys_ioctl+0x8f/0xd0 do_syscall_64+0x62/0x940 entry_SYSCALL_64_after_hwframe+0x4b/0x53 </TASK> ---[ end trace 0000000000000000 ]--- This can happen if the guest executes WRMSR(MSR_IA32_XFD) to set XFD[18] = 1, and a host IRQ triggers kernel_fpu_begin() prior to the vmexit handler's call to fpu_update_guest_xfd(). and if userspace stuffs XSTATE_BV[i]=1 via KVM_SET_XSAVE: ------------[ cut here ]------------ WARNING: arch/x86/kernel/traps.c:1524 at exc_device_not_available+0x101/0x110, CPU#14: amx_test/867 Modules linked in: kvm_intel kvm irqbypass CPU: 14 UID: 1000 PID: 867 Comm: amx_test Not tainted 6.19.0-rc2-2dace9faccd6-x86_amx_nm_xfd_non_init-vm #168 NONE Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 RIP: 0010:exc_device_not_available+0x101/0x110 Call Trace: <TASK> asm_exc_device_not_available+0x1a/0x20 RIP: 0010:restore_fpregs_from_fpstate+0x36/0x90 fpu_swap_kvm_fpstate+0x6b/0x120 kvm_load_guest_fpu+0x30/0x80 [kvm] kvm_arch_vcpu_ioctl_run+0x85/0x1e40 [kvm] kvm_vcpu_ioctl+0x2c3/0x8f0 [kvm] __x64_sys_ioctl+0x8f/0xd0 do_syscall_64+0x62/0x940 entry_SYSCALL_64_after_hwframe+0x4b/0x53 </TASK> ---[ end trace 0000000000000000 ]--- The new behavior is consistent with the AMX architecture. Per Intel's SDM, XSAVE saves XSTATE_BV as '0' for components that are disabled via XFD (and non-compacted XSAVE saves the initial configuration of the state component): If XSAVE, XSAVEC, XSAVEOPT, or XSAVES is saving the state component i, the instruction does not generate #NM when XCR0[i] = IA32_XFD[i] = 1; instead, it operates as if XINUSE[i] = 0 (and the state component was in its initial state): it saves bit i of XSTATE_BV field of the XSAVE header as 0; in addition, XSAVE saves the initial configuration of the state component (the other instructions do not save state component i). Alternatively, KVM could always do XRSTOR with XFD=0, e.g. by using a constant XFD based on the set of enabled features when XSAVEing for a struct fpu_guest. However, having XSTATE_BV[i]=1 for XFD-disabled features can only happen in the above interrupt case, or in similar scenarios involving preemption on preemptible kernels, because fpu_swap_kvm_fpstate()'s call to save_fpregs_to_fpstate() saves the outgoing FPU state with the current XFD; and that is (on all but the first WRMSR to XFD) the guest XFD. Therefore, XFD can only go out of sync with XSTATE_BV in the above interrupt case, or in similar scenarios involving preemption on preemptible kernels, and it we can consider it (de facto) part of KVM ABI that KVM_GET_XSAVE returns XSTATE_BV[i]=0 for XFD-disabled features. Reported-by: Paolo Bonzini <pbonzini(a)redhat.com> Cc: stable(a)vger.kernel.org Fixes: 820a6ee944e7 ("kvm: x86: Add emulation for IA32_XFD", 2022-01-14) Signed-off-by: Sean Christopherson <seanjc(a)google.com> [Move clearing of XSTATE_BV from fpu_copy_uabi_to_guest_fpstate to kvm_vcpu_ioctl_x86_set_xsave. - Paolo] Reviewed-by: Binbin Wu <binbin.wu(a)linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini(a)redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Conflicts: arch/x86/kvm/x86.c [Context difference. ] Signed-off-by: Zhang Kunbo <zhangkunbo(a)huawei.com> --- arch/x86/kernel/fpu/core.c | 32 +++++++++++++++++++++++++++++--- arch/x86/kvm/x86.c | 9 +++++++++ 2 files changed, 38 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index 1f0871be9d53..fd53ff26cd42 100644 --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -296,10 +296,29 @@ EXPORT_SYMBOL_GPL(fpu_enable_guest_xfd_features); #ifdef CONFIG_X86_64 void fpu_update_guest_xfd(struct fpu_guest *guest_fpu, u64 xfd) { + struct fpstate *fpstate = guest_fpu->fpstate; + fpregs_lock(); - guest_fpu->fpstate->xfd = xfd; - if (guest_fpu->fpstate->in_use) - xfd_update_state(guest_fpu->fpstate); + + /* + * KVM's guest ABI is that setting XFD[i]=1 *can* immediately revert the + * save state to its initial configuration. Likewise, KVM_GET_XSAVE does + * the same as XSAVE and returns XSTATE_BV[i]=0 whenever XFD[i]=1. + * + * If the guest's FPU state is in hardware, just update XFD: the XSAVE + * in fpu_swap_kvm_fpstate will clear XSTATE_BV[i] whenever XFD[i]=1. + * + * If however the guest's FPU state is NOT resident in hardware, clear + * disabled components in XSTATE_BV now, or a subsequent XRSTOR will + * attempt to load disabled components and generate #NM _in the host_. + */ + if (xfd && test_thread_flag(TIF_NEED_FPU_LOAD)) + fpstate->regs.xsave.header.xfeatures &= ~xfd; + + fpstate->xfd = xfd; + if (fpstate->in_use) + xfd_update_state(fpstate); + fpregs_unlock(); } EXPORT_SYMBOL_GPL(fpu_update_guest_xfd); @@ -407,6 +426,13 @@ int fpu_copy_uabi_to_guest_fpstate(struct fpu_guest *gfpu, const void *buf, if (ustate->xsave.header.xfeatures & ~xcr0) return -EINVAL; + /* + * Disabled features must be in their initial state, otherwise XRSTOR + * causes an exception. + */ + if (WARN_ON_ONCE(ustate->xsave.header.xfeatures & kstate->xfd)) + return -EINVAL; + /* * Nullify @vpkru to preserve its current value if PKRU's bit isn't set * in the header. KVM's odd ABI is to leave PKRU untouched in this diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 2139f728aecc..57fc6916906b 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -5541,9 +5541,18 @@ static void kvm_vcpu_ioctl_x86_get_xsave(struct kvm_vcpu *vcpu, static int kvm_vcpu_ioctl_x86_set_xsave(struct kvm_vcpu *vcpu, struct kvm_xsave *guest_xsave) { + union fpregs_state *xstate = (union fpregs_state *)guest_xsave->region; + if (fpstate_is_confidential(&vcpu->arch.guest_fpu)) return 0; + /* + * For backwards compatibility, do not expect disabled features to be in + * their initial state. XSTATE_BV[i] must still be cleared whenever + * XFD[i]=1, or XRSTOR would cause a #NM. + */ + xstate->xsave.header.xfeatures &= ~vcpu->arch.guest_fpu.fpstate->xfd; + return fpu_copy_uabi_to_guest_fpstate(&vcpu->arch.guest_fpu, guest_xsave->region, kvm_caps.supported_xcr0, -- 2.34.1

2 1

[PATCH v11 00/14] arm64: entry: Convert to Generic Entry
by Jinjie Ruan 28 Jan '26

28 Jan '26

Currently, x86, Riscv, Loongarch use the Generic Entry which makes maintainers' work easier and codes more elegant. arm64 has already successfully switched to the Generic IRQ Entry in commit b3cf07851b6c ("arm64: entry: Switch to generic IRQ entry"), it is time to completely convert arm64 to Generic Entry. The goal is to bring arm64 in line with other architectures that already use the generic entry infrastructure, reducing duplicated code and making it easier to share future changes in entry/exit paths, such as "Syscall User Dispatch". This patch set is rebased on arm64 (for-next/entry). And the performance was measured on Kunpeng 920 using "perf bench basic syscall" with "arm64.nopauth selinux=0 audit=1". After switch to Generic Entry, the performance are below: | Metric | W/O Generic Framework | With Generic Framework | Change | | ---------- | --------------------- | ---------------------- | ------ | | Total time | 2.487 [sec] | 2.393[sec] | ↓3.8% | | usecs/op | 0.248780 | 0.239361 | ↓3.8% | | ops/sec | 4,019,620 | 4,177,789 | ↑3.9% | Compared to earlier with arch specific handling, the performance improved by approximately 3.9%. On the basis of optimizing syscall_get_arguments()[1], el0_svc_common() and syscall_exit_work(), the performance are below: | Metric | W/O Generic Entry | With Generic Entry opt| Change | | ---------- | ----------------- | ------------------ | ------ | | Total time | 2.487 [sec] | 2.264 [sec] | ↓9.0% | | usecs/op | 0.248780 | 0.226481 | ↓9.0% | | ops/sec | 4,019,620 | 4,415,383 | ↑9.8% | Therefore, after the optimization, ARM64 System Call performance improved by approximately 9%. It was tested ok with following test cases on kunpeng920 and QEMU virt platform: - Perf tests. - Different `dynamic preempt` mode switch. - Pseudo NMI tests. - Stress-ng CPU stress test. - Hackbench stress test. - MTE test case in Documentation/arch/arm64/memory-tagging-extension.rst and all test cases in tools/testing/selftests/arm64/mte/*. - "sud" selftest testcase. - get_set_sud, get_syscall_info, set_syscall_info, peeksiginfo in tools/testing/selftests/ptrace. - breakpoint_test_arm64 in selftests/breakpoints. - syscall-abi and ptrace in tools/testing/selftests/arm64/abi - fp-ptrace, sve-ptrace, za-ptrace in selftests/arm64/fp. - vdso_test_getrandom in tools/testing/selftests/vDSO - Strace tests. The test QEMU configuration is as follows: qemu-system-aarch64 \ -M virt,gic-version=3,virtualization=on,mte=on \ -cpu max,pauth-impdef=on \ -kernel Image \ -smp 8,sockets=1,cores=4,threads=2 \ -m 512m \ -nographic \ -no-reboot \ -device virtio-rng-pci \ -append "root=/dev/vda rw console=ttyAMA0 kgdboc=ttyAMA0,115200 \ earlycon preempt=voluntary irqchip.gicv3_pseudo_nmi=1" \ -drive if=none,file=images/rootfs.ext4,format=raw,id=hd0 \ -device virtio-blk-device,drive=hd0 \ [1]: https://kernel.googlesource.com/pub/scm/linux/kernel/git/akpm/mm/+/89bf683c… Changes in v11: - Remove unused syscall in syscall_trace_enter(). - Update and provide a detailed explanation of the differences after moving rseq_syscall() before audit_syscall_exit(). - Rebased on arm64 (for-next/entry), and remove the first applied 3 patchs. - syscall_exit_to_user_mode_work() for arch reuse instead of adding new syscall_exit_to_user_mode_work_prepare() helper. - Link to v10: https://lore.kernel.org/all/20251222114737.1334364-1-ruanjinjie@huawei.com/ Changes in v10: - Rebased on v6.19-rc1, rename syscall_exit_to_user_mode_prepare() to syscall_exit_to_user_mode_work_prepare() to avoid conflict. - Also inline syscall_trace_enter(). - Support aarch64 for sud_benchmark. - Update and correct the commit message. - Add Reviewed-by. - Link to v9: https://lore.kernel.org/all/20251204082123.2792067-1-ruanjinjie@huawei.com/ Changes in v9: - Move "Return early for ptrace_report_syscall_entry() error" patch ahead to make it not introduce a regression. - Not check _TIF_SECCOMP/SYSCALL_EMU for syscall_exit_work() in a separate patch. - Do not report_syscall_exit() for PTRACE_SYSEMU_SINGLESTEP in a separate patch. - Add two performance patch to improve the arm64 performance. - Add Reviewed-by. - Link to v8: https://lore.kernel.org/all/20251126071446.3234218-1-ruanjinjie@huawei.com/ Changes in v8: - Rename "report_syscall_enter()" to "report_syscall_entry()". - Add ptrace_save_reg() to avoid duplication. - Remove unused _TIF_WORK_MASK in a standalone patch. - Align syscall_trace_enter() return value with the generic version. - Use "scno" instead of regs->syscallno in el0_svc_common(). - Move rseq_syscall() ahead in a standalone patch to clarify it clearly. - Rename "syscall_trace_exit()" to "syscall_exit_work()". - Keep the goto in el0_svc_common(). - No argument was passed to __secure_computing() and check -1 not -1L. - Remove "Add has_syscall_work() helper" patch. - Move "Add syscall_exit_to_user_mode_prepare() helper" patch later. - Add miss header for asm/entry-common.h. - Update the implementation of arch_syscall_is_vdso_sigreturn(). - Add "ARCH_SYSCALL_WORK_EXIT" to be defined as "SECCOMP | SYSCALL_EMU" to keep the behaviour unchanged. - Add more testcases test. - Add Reviewed-by. - Update the commit message. - Link to v7: https://lore.kernel.org/all/20251117133048.53182-1-ruanjinjie@huawei.com/ Chanegs in v7: - Support "Syscall User Dispatch" by implementing arch_syscall_is_vdso_sigreturn() as kemal suggested. - Add aarch64 support for "sud" selftest testcase, which tested ok with the patch series. - Fix the kernel test robot warning for arch_ptrace_report_syscall_entry() and arch_ptrace_report_syscall_exit() in asm/entry-common.h. - Add perf syscall performance test. - Link to v6: https://lore.kernel.org/all/20250916082611.2972008-1-ruanjinjie@huawei.com/ Changes in v6: - Rebased on v6.17-rc5-next as arm64 generic irq entry has merged. - Update the commit message. - Link to v5: https://lore.kernel.org/all/20241206101744.4161990-1-ruanjinjie@huawei.com/ Changes in v5: - Not change arm32 and keep inerrupts_enabled() macro for gicv3 driver. - Move irqentry_state definition into arch/arm64/kernel/entry-common.c. - Avoid removing the __enter_from_*() and __exit_to_*() wrappers. - Update "irqentry_state_t ret/irq_state" to "state" to keep it consistently. - Use generic irq entry header for PREEMPT_DYNAMIC after split the generic entry. - Also refactor the ARM64 syscall code. - Introduce arch_ptrace_report_syscall_entry/exit(), instead of arch_pre/post_report_syscall_entry/exit() to simplify code. - Make the syscall patches clear separation. - Update the commit message. - Link to v4: https://lore.kernel.org/all/20241025100700.3714552-1-ruanjinjie@huawei.com/ Changes in v4: - Rework/cleanup split into a few patches as Mark suggested. - Replace interrupts_enabled() macro with regs_irqs_disabled(), instead of left it here. - Remove rcu and lockdep state in pt_regs by using temporary irqentry_state_t as Mark suggested. - Remove some unnecessary intermediate functions to make it clear. - Rework preempt irq and PREEMPT_DYNAMIC code to make the switch more clear. - arch_prepare_*_entry/exit() -> arch_pre_*_entry/exit(). - Expand the arch functions comment. - Make arch functions closer to its caller. - Declare saved_reg in for block. - Remove arch_exit_to_kernel_mode_prepare(), arch_enter_from_kernel_mode(). - Adjust "Add few arch functions to use generic entry" patch to be the penultimate. - Update the commit message. - Add suggested-by. - Link to v3: https://lore.kernel.org/all/20240629085601.470241-1-ruanjinjie@huawei.com/ Changes in v3: - Test the MTE test cases. - Handle forget_syscall() in arch_post_report_syscall_entry() - Make the arch funcs not use __weak as Thomas suggested, so move the arch funcs to entry-common.h, and make arch_forget_syscall() folded in arch_post_report_syscall_entry() as suggested. - Move report_single_step() to thread_info.h for arm64 - Change __always_inline() to inline, add inline for the other arch funcs. - Remove unused signal.h for entry-common.h. - Add Suggested-by. - Update the commit message. Changes in v2: - Add tested-by. - Fix a bug that not call arch_post_report_syscall_entry() in syscall_trace_enter() if ptrace_report_syscall_entry() return not zero. - Refactor report_syscall(). - Add comment for arch_prepare_report_syscall_exit(). - Adjust entry-common.h header file inclusion to alphabetical order. - Update the commit message. Jinjie Ruan (13): entry: Remove unused syscall in syscall_trace_enter() arm64/ptrace: Refactor syscall_trace_enter/exit() arm64: ptrace: Move rseq_syscall() before audit_syscall_exit() arm64: syscall: Rework el0_svc_common() arm64/ptrace: Not check _TIF_SECCOMP/SYSCALL_EMU for syscall_exit_work() arm64/ptrace: Do not report_syscall_exit() for PTRACE_SYSEMU_SINGLESTEP arm64/ptrace: Expand secure_computing() in place arm64/ptrace: Use syscall_get_arguments() helper entry: Rework syscall_exit_to_user_mode_work() for arch reuse entry: Add arch_ptrace_report_syscall_entry/exit() arm64: entry: Convert to generic entry arm64: Inline el0_svc_common() entry: Inline syscall_exit_work() and syscall_trace_enter() kemal (1): selftests: sud_test: Support aarch64 arch/arm64/Kconfig | 2 +- arch/arm64/include/asm/entry-common.h | 76 +++++++++ arch/arm64/include/asm/syscall.h | 19 ++- arch/arm64/include/asm/thread_info.h | 16 +- arch/arm64/kernel/debug-monitors.c | 7 + arch/arm64/kernel/ptrace.c | 115 ------------- arch/arm64/kernel/signal.c | 2 +- arch/arm64/kernel/syscall.c | 29 +--- include/linux/entry-common.h | 158 ++++++++++++++++-- kernel/entry/common.h | 7 - kernel/entry/syscall-common.c | 96 +---------- kernel/entry/syscall_user_dispatch.c | 4 +- .../syscall_user_dispatch/sud_benchmark.c | 2 +- .../syscall_user_dispatch/sud_test.c | 4 + 14 files changed, 268 insertions(+), 269 deletions(-) delete mode 100644 kernel/entry/common.h -- 2.34.1

1 14

[PATCH OLK-6.6 0/2] Fix exception when umount with release dev fd
by Hongbo Li 28 Jan '26

28 Jan '26

Fix exception when umount with release dev fd. Hongbo Li (2): mfs: Fix wild-memory-access error when mfs event is destroy. mfs: Do not release the async event immediately when read failed fs/mfs/cache.c | 2 ++ fs/mfs/dev.c | 12 ++++++++---- fs/mfs/super.c | 6 +++++- 3 files changed, 15 insertions(+), 5 deletions(-) -- 2.34.1

2 3

[PATCH OLK-6.6] tracing: Fix crash on synthetic stacktrace field usage
by Tengda Wu 28 Jan '26

28 Jan '26

From: Steven Rostedt <rostedt(a)goodmis.org> mainline inclusion from mainline-v6.19-rc4 commit 90f9f5d64cae4e72defd96a2a22760173cb3c9ec category: bugfix bugzilla: https://atomgit.com/openeuler/kernel/issues/8435 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- When creating a synthetic event based on an existing synthetic event that had a stacktrace field and the new synthetic event used that field a kernel crash occurred: ~# cd /sys/kernel/tracing ~# echo 's:stack unsigned long stack[];' > dynamic_events ~# echo 'hist:keys=prev_pid:s0=common_stacktrace if prev_state & 3' >> events/sched/sched_switch/trigger ~# echo 'hist:keys=next_pid:s1=$s0:onmatch(sched.sched_switch).trace(stack,$s1)' >> events/sched/sched_switch/trigger The above creates a synthetic event that takes a stacktrace when a task schedules out in a non-running state and passes that stacktrace to the sched_switch event when that task schedules back in. It triggers the "stack" synthetic event that has a stacktrace as its field (called "stack"). ~# echo 's:syscall_stack s64 id; unsigned long stack[];' >> dynamic_events ~# echo 'hist:keys=common_pid:s2=stack' >> events/synthetic/stack/trigger ~# echo 'hist:keys=common_pid:s3=$s2,i0=id:onmatch(synthetic.stack).trace(syscall_stack,$i0,$s3)' >> events/raw_syscalls/sys_exit/trigger The above makes another synthetic event called "syscall_stack" that attaches the first synthetic event (stack) to the sys_exit trace event and records the stacktrace from the stack event with the id of the system call that is exiting. When enabling this event (or using it in a historgram): ~# echo 1 > events/synthetic/syscall_stack/enable Produces a kernel crash! BUG: unable to handle page fault for address: 0000000000400010 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: Oops: 0000 [#1] SMP PTI CPU: 6 UID: 0 PID: 1257 Comm: bash Not tainted 6.16.3+deb14-amd64 #1 PREEMPT(lazy) Debian 6.16.3-1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.17.0-debian-1.17.0-1 04/01/2014 RIP: 0010:trace_event_raw_event_synth+0x90/0x380 Code: c5 00 00 00 00 85 d2 0f 84 e1 00 00 00 31 db eb 34 0f 1f 00 66 66 2e 0f 1f 84 00 00 00 00 00 66 66 2e 0f 1f 84 00 00 00 00 00 <49> 8b 04 24 48 83 c3 01 8d 0c c5 08 00 00 00 01 cd 41 3b 5d 40 0f RSP: 0018:ffffd2670388f958 EFLAGS: 00010202 RAX: ffff8ba1065cc100 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000001 RSI: fffff266ffda7b90 RDI: ffffd2670388f9b0 RBP: 0000000000000010 R08: ffff8ba104e76000 R09: ffffd2670388fa50 R10: ffff8ba102dd42e0 R11: ffffffff9a908970 R12: 0000000000400010 R13: ffff8ba10a246400 R14: ffff8ba10a710220 R15: fffff266ffda7b90 FS: 00007fa3bc63f740(0000) GS:ffff8ba2e0f48000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000400010 CR3: 0000000107f9e003 CR4: 0000000000172ef0 Call Trace: <TASK> ? __tracing_map_insert+0x208/0x3a0 action_trace+0x67/0x70 event_hist_trigger+0x633/0x6d0 event_triggers_call+0x82/0x130 trace_event_buffer_commit+0x19d/0x250 trace_event_raw_event_sys_exit+0x62/0xb0 syscall_exit_work+0x9d/0x140 do_syscall_64+0x20a/0x2f0 ? trace_event_raw_event_sched_switch+0x12b/0x170 ? save_fpregs_to_fpstate+0x3e/0x90 ? _raw_spin_unlock+0xe/0x30 ? finish_task_switch.isra.0+0x97/0x2c0 ? __rseq_handle_notify_resume+0xad/0x4c0 ? __schedule+0x4b8/0xd00 ? restore_fpregs_from_fpstate+0x3c/0x90 ? switch_fpu_return+0x5b/0xe0 ? do_syscall_64+0x1ef/0x2f0 ? do_fault+0x2e9/0x540 ? __handle_mm_fault+0x7d1/0xf70 ? count_memcg_events+0x167/0x1d0 ? handle_mm_fault+0x1d7/0x2e0 ? do_user_addr_fault+0x2c3/0x7f0 entry_SYSCALL_64_after_hwframe+0x76/0x7e The reason is that the stacktrace field is not labeled as such, and is treated as a normal field and not as a dynamic event that it is. In trace_event_raw_event_synth() the event is field is still treated as a dynamic array, but the retrieval of the data is considered a normal field, and the reference is just the meta data: // Meta data is retrieved instead of a dynamic array str_val = (char *)(long)var_ref_vals[val_idx]; // Then when it tries to process it: len = *((unsigned long *)str_val) + 1; It triggers a kernel page fault. To fix this, first when defining the fields of the first synthetic event, set the filter type to FILTER_STACKTRACE. This is used later by the second synthetic event to know that this field is a stacktrace. When creating the field of the new synthetic event, have it use this FILTER_STACKTRACE to know to create a stacktrace field to copy the stacktrace into. Cc: stable(a)vger.kernel.org Cc: Masami Hiramatsu <mhiramat(a)kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers(a)efficios.com> Cc: Tom Zanussi <zanussi(a)kernel.org> Link: https://patch.msgid.link/20260122194824.6905a38e@gandalf.local.home Fixes: 00cf3d672a9d ("tracing: Allow synthetic events to pass around stacktraces") Signed-off-by: Steven Rostedt (Google) <rostedt(a)goodmis.org> Signed-off-by: Tengda Wu <wutengda2(a)huawei.com> --- kernel/trace/trace_events_hist.c | 9 +++++++++ kernel/trace/trace_events_synth.c | 8 +++++++- 2 files changed, 16 insertions(+), 1 deletion(-) diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index 2d6f3c63bc62..f22aa4afaa6d 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -2047,6 +2047,15 @@ static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data, hist_field->fn_num = HIST_FIELD_FN_RELDYNSTRING; else hist_field->fn_num = HIST_FIELD_FN_PSTRING; + } else if (field->filter_type == FILTER_STACKTRACE) { + flags |= HIST_FIELD_FL_STACKTRACE; + + hist_field->size = MAX_FILTER_STR_VAL; + hist_field->type = kstrdup_const(field->type, GFP_KERNEL); + if (!hist_field->type) + goto free; + + hist_field->fn_num = HIST_FIELD_FN_STACK; } else { hist_field->size = field->size; hist_field->is_signed = field->is_signed; diff --git a/kernel/trace/trace_events_synth.c b/kernel/trace/trace_events_synth.c index 794e72dbb12d..13c2d3ad7185 100644 --- a/kernel/trace/trace_events_synth.c +++ b/kernel/trace/trace_events_synth.c @@ -137,7 +137,9 @@ static int synth_event_define_fields(struct trace_event_call *call) struct synth_event *event = call->data; unsigned int i, size, n_u64; char *name, *type; + int filter_type; bool is_signed; + bool is_stack; int ret = 0; for (i = 0, n_u64 = 0; i < event->n_fields; i++) { @@ -145,8 +147,12 @@ static int synth_event_define_fields(struct trace_event_call *call) is_signed = event->fields[i]->is_signed; type = event->fields[i]->type; name = event->fields[i]->name; + is_stack = event->fields[i]->is_stack; + + filter_type = is_stack ? FILTER_STACKTRACE : FILTER_OTHER; + ret = trace_define_field(call, type, name, offset, size, - is_signed, FILTER_OTHER); + is_signed, filter_type); if (ret) break; -- 2.34.1

2 1

[PATCH OLK-6.6] ima: don't clear IMA_DIGSIG flag when setting or removing non-IMA xattr
by Zhao Yipeng 27 Jan '26

27 Jan '26

From: Coiby Xu <coxu(a)redhat.com> stable inclusion from stable-v6.6.117 commit d2993a7e98eb70c737c6f5365a190e79c72b8407 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/11626 CVE: CVE-2025-68183 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit 88b4cbcf6b041ae0f2fc8a34554a5b6a83a2b7cd ] Currently when both IMA and EVM are in fix mode, the IMA signature will be reset to IMA hash if a program first stores IMA signature in security.ima and then writes/removes some other security xattr for the file. For example, on Fedora, after booting the kernel with "ima_appraise=fix evm=fix ima_policy=appraise_tcb" and installing rpm-plugin-ima, installing/reinstalling a package will not make good reference IMA signature generated. Instead IMA hash is generated, # getfattr -m - -d -e hex /usr/bin/bash # file: usr/bin/bash security.ima=0x0404... This happens because when setting security.selinux, the IMA_DIGSIG flag that had been set early was cleared. As a result, IMA hash is generated when the file is closed. Similarly, IMA signature can be cleared on file close after removing security xattr like security.evm or setting/removing ACL. Prevent replacing the IMA file signature with a file hash, by preventing the IMA_DIGSIG flag from being reset. Here's a minimal C reproducer which sets security.selinux as the last step which can also replaced by removing security.evm or setting ACL, #include <stdio.h> #include <sys/xattr.h> #include <fcntl.h> #include <unistd.h> #include <string.h> #include <stdlib.h> int main() { const char* file_path = "/usr/sbin/test_binary"; const char* hex_string = "030204d33204490066306402304"; int length = strlen(hex_string); char* ima_attr_value; int fd; fd = open(file_path, O_WRONLY|O_CREAT|O_EXCL, 0644); if (fd == -1) { perror("Error opening file"); return 1; } ima_attr_value = (char*)malloc(length / 2 ); for (int i = 0, j = 0; i < length; i += 2, j++) { sscanf(hex_string + i, "%2hhx", &ima_attr_value[j]); } if (fsetxattr(fd, "security.ima", ima_attr_value, length/2, 0) == -1) { perror("Error setting extended attribute"); close(fd); return 1; } const char* selinux_value= "system_u:object_r:bin_t:s0"; if (fsetxattr(fd, "security.selinux", selinux_value, strlen(selinux_value), 0) == -1) { perror("Error setting extended attribute"); close(fd); return 1; } close(fd); return 0; } Signed-off-by: Coiby Xu <coxu(a)redhat.com> Signed-off-by: Mimi Zohar <zohar(a)linux.ibm.com> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Zhao Yipeng <zhaoyipeng5(a)huawei.com> --- security/integrity/ima/ima_appraise.c | 23 ++++++++++++++++++----- 1 file changed, 18 insertions(+), 5 deletions(-) diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c index 8a54399d212d..a9e31d8addc6 100644 --- a/security/integrity/ima/ima_appraise.c +++ b/security/integrity/ima/ima_appraise.c @@ -809,6 +809,15 @@ static int ima_protect_xattr(struct dentry *dentry, const char *xattr_name, return 0; } +/* + * ima_reset_appraise_flags - reset ima_iint_cache flags + * + * @digsig: whether to clear/set IMA_DIGSIG flag, tristate values + * 0: clear IMA_DIGSIG + * 1: set IMA_DIGSIG + * -1: don't change IMA_DIGSIG + * + */ static void ima_reset_appraise_flags(struct inode *inode, int digsig) { struct integrity_iint_cache *iint; @@ -821,9 +830,9 @@ static void ima_reset_appraise_flags(struct inode *inode, int digsig) return; iint->measured_pcrs = 0; set_bit(IMA_CHANGE_XATTR, &iint->atomic_flags); - if (digsig) + if (digsig == 1) set_bit(IMA_DIGSIG, &iint->atomic_flags); - else + else if (digsig == 0) clear_bit(IMA_DIGSIG, &iint->atomic_flags); } @@ -908,6 +917,8 @@ int ima_inode_setxattr(struct dentry *dentry, const char *xattr_name, digsig = (xvalue->type == EVM_IMA_XATTR_DIGSIG); } else if (!strcmp(xattr_name, XATTR_NAME_EVM) && xattr_value_len > 0) { digsig = (xvalue->type == EVM_XATTR_PORTABLE_DIGSIG); + } else { + digsig = -1; } if (result == 1 || evm_revalidate_status(xattr_name)) { ima_reset_appraise_flags(d_backing_inode(dentry), digsig); @@ -921,18 +932,20 @@ int ima_inode_set_acl(struct mnt_idmap *idmap, struct dentry *dentry, const char *acl_name, struct posix_acl *kacl) { if (evm_revalidate_status(acl_name)) - ima_reset_appraise_flags(d_backing_inode(dentry), 0); + ima_reset_appraise_flags(d_backing_inode(dentry), -1); return 0; } int ima_inode_removexattr(struct dentry *dentry, const char *xattr_name) { - int result; + int result, digsig = -1; result = ima_protect_xattr(dentry, xattr_name, NULL, 0); if (result == 1 || evm_revalidate_status(xattr_name)) { - ima_reset_appraise_flags(d_backing_inode(dentry), 0); + if (!strcmp(xattr_name, XATTR_NAME_IMA)) + digsig = 0; + ima_reset_appraise_flags(d_backing_inode(dentry), digsig); if (result == 1) result = 0; } -- 2.34.1

2 1

[PATCH OLK-5.10] wifi: prevent A-MSDU attacks in mesh networks
by Zhang Yuwei 27 Jan '26

27 Jan '26

From: Mathy Vanhoef <Mathy.Vanhoef(a)kuleuven.be> stable inclusion from stable-v6.1.146 commit e2c8a3c0388aef6bfc4aabfba07bc7dff16eea80 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/7758 CVE: CVE-2025-27558 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- commit 737bb912ebbe4571195c56eba557c4d7315b26fb upstream. This patch is a mitigation to prevent the A-MSDU spoofing vulnerability for mesh networks. The initial update to the IEEE 802.11 standard, in response to the FragAttacks, missed this case (CVE-2025-27558). It can be considered a variant of CVE-2020-24588 but for mesh networks. This patch tries to detect if a standard MSDU was turned into an A-MSDU by an adversary. This is done by parsing a received A-MSDU as a standard MSDU, calculating the length of the Mesh Control header, and seeing if the 6 bytes after this header equal the start of an rfc1042 header. If equal, this is a strong indication of an ongoing attack attempt. This defense was tested with mac80211_hwsim against a mesh network that uses an empty Mesh Address Extension field, i.e., when four addresses are used, and when using a 12-byte Mesh Address Extension field, i.e., when six addresses are used. Functionality of normal MSDUs and A-MSDUs was also tested, and confirmed working, when using both an empty and 12-byte Mesh Address Extension field. It was also tested with mac80211_hwsim that A-MSDU attacks in non-mesh networks keep being detected and prevented. Note that the vulnerability being patched, and the defense being implemented, was also discussed in the following paper and in the following IEEE 802.11 presentation: https://papers.mathyvanhoef.com/wisec2025.pdf https://mentor.ieee.org/802.11/dcn/25/11-25-0949-00-000m-a-msdu-mesh-spoof-… Cc: stable(a)vger.kernel.org Signed-off-by: Mathy Vanhoef <Mathy.Vanhoef(a)kuleuven.be> Link: https://patch.msgid.link/20250616004635.224344-1-Mathy.Vanhoef@kuleuven.be Signed-off-by: Johannes Berg <johannes.berg(a)intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Conflicts: net/wireless/util.c [Fanhua Li: context conflict] Signed-off-by: Fanhua Li <lifanhua5(a)huawei.com> --- net/wireless/util.c | 51 +++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 49 insertions(+), 2 deletions(-) diff --git a/net/wireless/util.c b/net/wireless/util.c index 15773db362a1..81ac8d1da085 100644 --- a/net/wireless/util.c +++ b/net/wireless/util.c @@ -742,6 +742,51 @@ __ieee80211_amsdu_copy(struct sk_buff *skb, unsigned int hlen, return frame; } +/* + * Detects if an MSDU frame was maliciously converted into an A-MSDU + * frame by an adversary. This is done by parsing the received frame + * as if it were a regular MSDU, even though the A-MSDU flag is set. + * + * For non-mesh interfaces, detection involves checking whether the + * payload, when interpreted as an MSDU, begins with a valid RFC1042 + * header. This is done by comparing the A-MSDU subheader's destination + * address to the start of the RFC1042 header. + * + * For mesh interfaces, the MSDU includes a 6-byte Mesh Control field + * and an optional variable-length Mesh Address Extension field before + * the RFC1042 header. The position of the RFC1042 header must therefore + * be calculated based on the mesh header length. + * + * Since this function intentionally parses an A-MSDU frame as an MSDU, + * it only assumes that the A-MSDU subframe header is present, and + * beyond this it performs its own bounds checks under the assumption + * that the frame is instead parsed as a non-aggregated MSDU. + */ +static bool +is_amsdu_aggregation_attack(struct ethhdr *eth, struct sk_buff *skb, + enum nl80211_iftype iftype) +{ + int offset; + + /* Non-mesh case can be directly compared */ + if (iftype != NL80211_IFTYPE_MESH_POINT) + return ether_addr_equal(eth->h_dest, rfc1042_header); + + offset = __ieee80211_get_mesh_hdrlen(eth->h_dest[0]); + if (offset == 6) { + /* Mesh case with empty address extension field */ + return ether_addr_equal(eth->h_source, rfc1042_header); + } else if (offset + ETH_ALEN <= skb->len) { + /* Mesh case with non-empty address extension field */ + u8 temp[ETH_ALEN]; + + skb_copy_bits(skb, offset, temp, ETH_ALEN); + return ether_addr_equal(temp, rfc1042_header); + } + + return false; +} + void ieee80211_amsdu_to_8023s(struct sk_buff *skb, struct sk_buff_head *list, const u8 *addr, enum nl80211_iftype iftype, const unsigned int extra_headroom, @@ -774,8 +819,10 @@ void ieee80211_amsdu_to_8023s(struct sk_buff *skb, struct sk_buff_head *list, /* the last MSDU has no padding */ if (subframe_len > remaining) goto purge; - /* mitigate A-MSDU aggregation injection attacks */ - if (ether_addr_equal(eth.h_dest, rfc1042_header)) + /* mitigate A-MSDU aggregation injection attacks, to be + * checked when processing first subframe (offset == 0). + */ + if (offset == 0 && is_amsdu_aggregation_attack(&eth, skb, iftype)) goto purge; offset += sizeof(struct ethhdr); -- 2.22.0

2 1

[PATCH OLK-6.6] wifi: prevent A-MSDU attacks in mesh networks
by Zhang Yuwei 27 Jan '26

27 Jan '26

From: Mathy Vanhoef <Mathy.Vanhoef(a)kuleuven.be> stable inclusion from stable-v6.6.99 commit ec6392061de6681148b63ee6c8744da833498cdd category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/7758 CVE: CVE-2025-27558 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- commit 737bb912ebbe4571195c56eba557c4d7315b26fb upstream. This patch is a mitigation to prevent the A-MSDU spoofing vulnerability for mesh networks. The initial update to the IEEE 802.11 standard, in response to the FragAttacks, missed this case (CVE-2025-27558). It can be considered a variant of CVE-2020-24588 but for mesh networks. This patch tries to detect if a standard MSDU was turned into an A-MSDU by an adversary. This is done by parsing a received A-MSDU as a standard MSDU, calculating the length of the Mesh Control header, and seeing if the 6 bytes after this header equal the start of an rfc1042 header. If equal, this is a strong indication of an ongoing attack attempt. This defense was tested with mac80211_hwsim against a mesh network that uses an empty Mesh Address Extension field, i.e., when four addresses are used, and when using a 12-byte Mesh Address Extension field, i.e., when six addresses are used. Functionality of normal MSDUs and A-MSDUs was also tested, and confirmed working, when using both an empty and 12-byte Mesh Address Extension field. It was also tested with mac80211_hwsim that A-MSDU attacks in non-mesh networks keep being detected and prevented. Note that the vulnerability being patched, and the defense being implemented, was also discussed in the following paper and in the following IEEE 802.11 presentation: https://papers.mathyvanhoef.com/wisec2025.pdf https://mentor.ieee.org/802.11/dcn/25/11-25-0949-00-000m-a-msdu-mesh-spoof-… Cc: stable(a)vger.kernel.org Signed-off-by: Mathy Vanhoef <Mathy.Vanhoef(a)kuleuven.be> Link: https://patch.msgid.link/20250616004635.224344-1-Mathy.Vanhoef@kuleuven.be Signed-off-by: Johannes Berg <johannes.berg(a)intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Wang Hai <wanghai38(a)huawei.com> --- net/wireless/util.c | 52 +++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 50 insertions(+), 2 deletions(-) diff --git a/net/wireless/util.c b/net/wireless/util.c index 7acd8d0db61a..24e5af65da58 100644 --- a/net/wireless/util.c +++ b/net/wireless/util.c @@ -826,6 +826,52 @@ bool ieee80211_is_valid_amsdu(struct sk_buff *skb, u8 mesh_hdr) } EXPORT_SYMBOL(ieee80211_is_valid_amsdu); + +/* + * Detects if an MSDU frame was maliciously converted into an A-MSDU + * frame by an adversary. This is done by parsing the received frame + * as if it were a regular MSDU, even though the A-MSDU flag is set. + * + * For non-mesh interfaces, detection involves checking whether the + * payload, when interpreted as an MSDU, begins with a valid RFC1042 + * header. This is done by comparing the A-MSDU subheader's destination + * address to the start of the RFC1042 header. + * + * For mesh interfaces, the MSDU includes a 6-byte Mesh Control field + * and an optional variable-length Mesh Address Extension field before + * the RFC1042 header. The position of the RFC1042 header must therefore + * be calculated based on the mesh header length. + * + * Since this function intentionally parses an A-MSDU frame as an MSDU, + * it only assumes that the A-MSDU subframe header is present, and + * beyond this it performs its own bounds checks under the assumption + * that the frame is instead parsed as a non-aggregated MSDU. + */ +static bool +is_amsdu_aggregation_attack(struct ethhdr *eth, struct sk_buff *skb, + enum nl80211_iftype iftype) +{ + int offset; + + /* Non-mesh case can be directly compared */ + if (iftype != NL80211_IFTYPE_MESH_POINT) + return ether_addr_equal(eth->h_dest, rfc1042_header); + + offset = __ieee80211_get_mesh_hdrlen(eth->h_dest[0]); + if (offset == 6) { + /* Mesh case with empty address extension field */ + return ether_addr_equal(eth->h_source, rfc1042_header); + } else if (offset + ETH_ALEN <= skb->len) { + /* Mesh case with non-empty address extension field */ + u8 temp[ETH_ALEN]; + + skb_copy_bits(skb, offset, temp, ETH_ALEN); + return ether_addr_equal(temp, rfc1042_header); + } + + return false; +} + void ieee80211_amsdu_to_8023s(struct sk_buff *skb, struct sk_buff_head *list, const u8 *addr, enum nl80211_iftype iftype, const unsigned int extra_headroom, @@ -867,8 +913,10 @@ void ieee80211_amsdu_to_8023s(struct sk_buff *skb, struct sk_buff_head *list, /* the last MSDU has no padding */ if (subframe_len > remaining) goto purge; - /* mitigate A-MSDU aggregation injection attacks */ - if (ether_addr_equal(hdr.eth.h_dest, rfc1042_header)) + /* mitigate A-MSDU aggregation injection attacks, to be + * checked when processing first subframe (offset == 0). + */ + if (offset == 0 && is_amsdu_aggregation_attack(&hdr.eth, skb, iftype)) goto purge; offset += sizeof(struct ethhdr); -- 2.22.0

2 1

[PATCH OLK-5.10] wifi: prevent A-MSDU attacks in mesh networks
by Fanhua Li 27 Jan '26

27 Jan '26

From: Mathy Vanhoef <Mathy.Vanhoef(a)kuleuven.be> stable inclusion from stable-v6.1.146 commit e2c8a3c0388aef6bfc4aabfba07bc7dff16eea80 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/9288 CVE: CVE-2025-38512 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- commit 737bb912ebbe4571195c56eba557c4d7315b26fb upstream. This patch is a mitigation to prevent the A-MSDU spoofing vulnerability for mesh networks. The initial update to the IEEE 802.11 standard, in response to the FragAttacks, missed this case (CVE-2025-27558). It can be considered a variant of CVE-2020-24588 but for mesh networks. This patch tries to detect if a standard MSDU was turned into an A-MSDU by an adversary. This is done by parsing a received A-MSDU as a standard MSDU, calculating the length of the Mesh Control header, and seeing if the 6 bytes after this header equal the start of an rfc1042 header. If equal, this is a strong indication of an ongoing attack attempt. This defense was tested with mac80211_hwsim against a mesh network that uses an empty Mesh Address Extension field, i.e., when four addresses are used, and when using a 12-byte Mesh Address Extension field, i.e., when six addresses are used. Functionality of normal MSDUs and A-MSDUs was also tested, and confirmed working, when using both an empty and 12-byte Mesh Address Extension field. It was also tested with mac80211_hwsim that A-MSDU attacks in non-mesh networks keep being detected and prevented. Note that the vulnerability being patched, and the defense being implemented, was also discussed in the following paper and in the following IEEE 802.11 presentation: https://papers.mathyvanhoef.com/wisec2025.pdf https://mentor.ieee.org/802.11/dcn/25/11-25-0949-00-000m-a-msdu-mesh-spoof-… Cc: stable(a)vger.kernel.org Signed-off-by: Mathy Vanhoef <Mathy.Vanhoef(a)kuleuven.be> Link: https://patch.msgid.link/20250616004635.224344-1-Mathy.Vanhoef@kuleuven.be Signed-off-by: Johannes Berg <johannes.berg(a)intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Conflicts: net/wireless/util.c [Fanhua Li: context conflict] Signed-off-by: Fanhua Li <lifanhua5(a)huawei.com> --- net/wireless/util.c | 51 +++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 49 insertions(+), 2 deletions(-) diff --git a/net/wireless/util.c b/net/wireless/util.c index 15773db362a15..81ac8d1da0854 100644 --- a/net/wireless/util.c +++ b/net/wireless/util.c @@ -742,6 +742,51 @@ __ieee80211_amsdu_copy(struct sk_buff *skb, unsigned int hlen, return frame; } +/* + * Detects if an MSDU frame was maliciously converted into an A-MSDU + * frame by an adversary. This is done by parsing the received frame + * as if it were a regular MSDU, even though the A-MSDU flag is set. + * + * For non-mesh interfaces, detection involves checking whether the + * payload, when interpreted as an MSDU, begins with a valid RFC1042 + * header. This is done by comparing the A-MSDU subheader's destination + * address to the start of the RFC1042 header. + * + * For mesh interfaces, the MSDU includes a 6-byte Mesh Control field + * and an optional variable-length Mesh Address Extension field before + * the RFC1042 header. The position of the RFC1042 header must therefore + * be calculated based on the mesh header length. + * + * Since this function intentionally parses an A-MSDU frame as an MSDU, + * it only assumes that the A-MSDU subframe header is present, and + * beyond this it performs its own bounds checks under the assumption + * that the frame is instead parsed as a non-aggregated MSDU. + */ +static bool +is_amsdu_aggregation_attack(struct ethhdr *eth, struct sk_buff *skb, + enum nl80211_iftype iftype) +{ + int offset; + + /* Non-mesh case can be directly compared */ + if (iftype != NL80211_IFTYPE_MESH_POINT) + return ether_addr_equal(eth->h_dest, rfc1042_header); + + offset = __ieee80211_get_mesh_hdrlen(eth->h_dest[0]); + if (offset == 6) { + /* Mesh case with empty address extension field */ + return ether_addr_equal(eth->h_source, rfc1042_header); + } else if (offset + ETH_ALEN <= skb->len) { + /* Mesh case with non-empty address extension field */ + u8 temp[ETH_ALEN]; + + skb_copy_bits(skb, offset, temp, ETH_ALEN); + return ether_addr_equal(temp, rfc1042_header); + } + + return false; +} + void ieee80211_amsdu_to_8023s(struct sk_buff *skb, struct sk_buff_head *list, const u8 *addr, enum nl80211_iftype iftype, const unsigned int extra_headroom, @@ -774,8 +819,10 @@ void ieee80211_amsdu_to_8023s(struct sk_buff *skb, struct sk_buff_head *list, /* the last MSDU has no padding */ if (subframe_len > remaining) goto purge; - /* mitigate A-MSDU aggregation injection attacks */ - if (ether_addr_equal(eth.h_dest, rfc1042_header)) + /* mitigate A-MSDU aggregation injection attacks, to be + * checked when processing first subframe (offset == 0). + */ + if (offset == 0 && is_amsdu_aggregation_attack(&eth, skb, iftype)) goto purge; offset += sizeof(struct ethhdr); -- 2.43.0

2 1

[PATCH OLK-5.10] mlxsw: spectrum_router: Fix neighbour use-after-free
by Cai Xinchen 27 Jan '26

27 Jan '26

From: Ido Schimmel <idosch(a)nvidia.com> stable inclusion from stable-v5.10.248 commit a2dfe6758fc63e542105bee8b17a3a7485684db0 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/13354 CVE: CVE-2025-68801 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit 8b0e69763ef948fb872a7767df4be665d18f5fd4 ] We sometimes observe use-after-free when dereferencing a neighbour [1]. The problem seems to be that the driver stores a pointer to the neighbour, but without holding a reference on it. A reference is only taken when the neighbour is used by a nexthop. Fix by simplifying the reference counting scheme. Always take a reference when storing a neighbour pointer in a neighbour entry. Avoid taking a referencing when the neighbour is used by a nexthop as the neighbour entry associated with the nexthop already holds a reference. Tested by running the test that uncovered the problem over 300 times. Without this patch the problem was reproduced after a handful of iterations. [1] BUG: KASAN: slab-use-after-free in mlxsw_sp_neigh_entry_update+0x2d4/0x310 Read of size 8 at addr ffff88817f8e3420 by task ip/3929 CPU: 3 UID: 0 PID: 3929 Comm: ip Not tainted 6.18.0-rc4-virtme-g36b21a067510 #3 PREEMPT(full) Hardware name: Nvidia SN5600/VMOD0013, BIOS 5.13 05/31/2023 Call Trace: <TASK> dump_stack_lvl+0x6f/0xa0 print_address_description.constprop.0+0x6e/0x300 print_report+0xfc/0x1fb kasan_report+0xe4/0x110 mlxsw_sp_neigh_entry_update+0x2d4/0x310 mlxsw_sp_router_rif_gone_sync+0x35f/0x510 mlxsw_sp_rif_destroy+0x1ea/0x730 mlxsw_sp_inetaddr_port_vlan_event+0xa1/0x1b0 __mlxsw_sp_inetaddr_lag_event+0xcc/0x130 __mlxsw_sp_inetaddr_event+0xf5/0x3c0 mlxsw_sp_router_netdevice_event+0x1015/0x1580 notifier_call_chain+0xcc/0x150 call_netdevice_notifiers_info+0x7e/0x100 __netdev_upper_dev_unlink+0x10b/0x210 netdev_upper_dev_unlink+0x79/0xa0 vrf_del_slave+0x18/0x50 do_set_master+0x146/0x7d0 do_setlink.isra.0+0x9a0/0x2880 rtnl_newlink+0x637/0xb20 rtnetlink_rcv_msg+0x6fe/0xb90 netlink_rcv_skb+0x123/0x380 netlink_unicast+0x4a3/0x770 netlink_sendmsg+0x75b/0xc90 __sock_sendmsg+0xbe/0x160 ____sys_sendmsg+0x5b2/0x7d0 ___sys_sendmsg+0xfd/0x180 __sys_sendmsg+0x124/0x1c0 do_syscall_64+0xbb/0xfd0 entry_SYSCALL_64_after_hwframe+0x4b/0x53 [...] Allocated by task 109: kasan_save_stack+0x30/0x50 kasan_save_track+0x14/0x30 __kasan_kmalloc+0x7b/0x90 __kmalloc_noprof+0x2c1/0x790 neigh_alloc+0x6af/0x8f0 ___neigh_create+0x63/0xe90 mlxsw_sp_nexthop_neigh_init+0x430/0x7e0 mlxsw_sp_nexthop_type_init+0x212/0x960 mlxsw_sp_nexthop6_group_info_init.constprop.0+0x81f/0x1280 mlxsw_sp_nexthop6_group_get+0x392/0x6a0 mlxsw_sp_fib6_entry_create+0x46a/0xfd0 mlxsw_sp_router_fib6_replace+0x1ed/0x5f0 mlxsw_sp_router_fib6_event_work+0x10a/0x2a0 process_one_work+0xd57/0x1390 worker_thread+0x4d6/0xd40 kthread+0x355/0x5b0 ret_from_fork+0x1d4/0x270 ret_from_fork_asm+0x11/0x20 Freed by task 154: kasan_save_stack+0x30/0x50 kasan_save_track+0x14/0x30 __kasan_save_free_info+0x3b/0x60 __kasan_slab_free+0x43/0x70 kmem_cache_free_bulk.part.0+0x1eb/0x5e0 kvfree_rcu_bulk+0x1f2/0x260 kfree_rcu_work+0x130/0x1b0 process_one_work+0xd57/0x1390 worker_thread+0x4d6/0xd40 kthread+0x355/0x5b0 ret_from_fork+0x1d4/0x270 ret_from_fork_asm+0x11/0x20 Last potentially related work creation: kasan_save_stack+0x30/0x50 kasan_record_aux_stack+0x8c/0xa0 kvfree_call_rcu+0x93/0x5b0 mlxsw_sp_router_neigh_event_work+0x67d/0x860 process_one_work+0xd57/0x1390 worker_thread+0x4d6/0xd40 kthread+0x355/0x5b0 ret_from_fork+0x1d4/0x270 ret_from_fork_asm+0x11/0x20 Fixes: 6cf3c971dc84 ("mlxsw: spectrum_router: Add private neigh table") Signed-off-by: Ido Schimmel <idosch(a)nvidia.com> Reviewed-by: Petr Machata <petrm(a)nvidia.com> Signed-off-by: Petr Machata <petrm(a)nvidia.com> Reviewed-by: Simon Horman <horms(a)kernel.org> Link: https://patch.msgid.link/92d75e21d95d163a41b5cea67a15cd33f547cba6.176469565… Signed-off-by: Jakub Kicinski <kuba(a)kernel.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Cai Xinchen <caixinchen1(a)huawei.com> --- .../ethernet/mellanox/mlxsw/spectrum_router.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c index d2887ae508bb..e22ee1336d74 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c @@ -2032,6 +2032,7 @@ mlxsw_sp_neigh_entry_alloc(struct mlxsw_sp *mlxsw_sp, struct neighbour *n, if (!neigh_entry) return NULL; + neigh_hold(n); neigh_entry->key.n = n; neigh_entry->rif = rif; INIT_LIST_HEAD(&neigh_entry->nexthop_list); @@ -2041,6 +2042,7 @@ mlxsw_sp_neigh_entry_alloc(struct mlxsw_sp *mlxsw_sp, struct neighbour *n, static void mlxsw_sp_neigh_entry_free(struct mlxsw_sp_neigh_entry *neigh_entry) { + neigh_release(neigh_entry->key.n); kfree(neigh_entry); } @@ -3607,6 +3609,8 @@ mlxsw_sp_nexthop_dead_neigh_replace(struct mlxsw_sp *mlxsw_sp, if (err) goto err_neigh_entry_insert; + neigh_release(old_n); + read_lock_bh(&n->lock); nud_state = n->nud_state; dead = n->dead; @@ -3615,14 +3619,10 @@ mlxsw_sp_nexthop_dead_neigh_replace(struct mlxsw_sp *mlxsw_sp, list_for_each_entry(nh, &neigh_entry->nexthop_list, neigh_list_node) { - neigh_release(old_n); - neigh_clone(n); __mlxsw_sp_nexthop_neigh_update(nh, !entry_connected); mlxsw_sp_nexthop_group_refresh(mlxsw_sp, nh->nh_grp); } - neigh_release(n); - return 0; err_neigh_entry_insert: @@ -3711,6 +3711,11 @@ static int mlxsw_sp_nexthop_neigh_init(struct mlxsw_sp *mlxsw_sp, } } + /* Release the reference taken by neigh_lookup() / neigh_create() since + * neigh_entry already holds one. + */ + neigh_release(n); + /* If that is the first nexthop connected to that neigh, add to * nexthop_neighs_list */ @@ -3737,11 +3742,9 @@ static void mlxsw_sp_nexthop_neigh_fini(struct mlxsw_sp *mlxsw_sp, struct mlxsw_sp_nexthop *nh) { struct mlxsw_sp_neigh_entry *neigh_entry = nh->neigh_entry; - struct neighbour *n; if (!neigh_entry) return; - n = neigh_entry->key.n; __mlxsw_sp_nexthop_neigh_update(nh, true); list_del(&nh->neigh_list_node); @@ -3755,8 +3758,6 @@ static void mlxsw_sp_nexthop_neigh_fini(struct mlxsw_sp *mlxsw_sp, if (!neigh_entry->connected && list_empty(&neigh_entry->nexthop_list)) mlxsw_sp_neigh_entry_destroy(mlxsw_sp, neigh_entry); - - neigh_release(n); } static bool mlxsw_sp_ipip_netdev_ul_up(struct net_device *ol_dev) -- 2.34.1

2 1

[PATCH OLK-5.10] mlxsw: spectrum_mr: Fix use-after-free when updating multicast route stats
by Cai Xinchen 27 Jan '26

27 Jan '26

From: Ido Schimmel <idosch(a)nvidia.com> stable inclusion from stable-v5.10.248 commit b957366f5611bbaba03dd10ef861283347ddcc88 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/13353 CVE: CVE-2025-68800 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit 8ac1dacec458f55f871f7153242ed6ab60373b90 ] Cited commit added a dedicated mutex (instead of RTNL) to protect the multicast route list, so that it will not change while the driver periodically traverses it in order to update the kernel about multicast route stats that were queried from the device. One instance of list entry deletion (during route replace) was missed and it can result in a use-after-free [1]. Fix by acquiring the mutex before deleting the entry from the list and releasing it afterwards. [1] BUG: KASAN: slab-use-after-free in mlxsw_sp_mr_stats_update+0x4a5/0x540 drivers/net/ethernet/mellanox/mlxsw/spectrum_mr.c:1006 [mlxsw_spectrum] Read of size 8 at addr ffff8881523c2fa8 by task kworker/2:5/22043 CPU: 2 UID: 0 PID: 22043 Comm: kworker/2:5 Not tainted 6.18.0-rc1-custom-g1a3d6d7cd014 #1 PREEMPT(full) Hardware name: Mellanox Technologies Ltd. MSN2010/SA002610, BIOS 5.6.5 08/24/2017 Workqueue: mlxsw_core mlxsw_sp_mr_stats_update [mlxsw_spectrum] Call Trace: <TASK> dump_stack_lvl+0xba/0x110 print_report+0x174/0x4f5 kasan_report+0xdf/0x110 mlxsw_sp_mr_stats_update+0x4a5/0x540 drivers/net/ethernet/mellanox/mlxsw/spectrum_mr.c:1006 [mlxsw_spectrum] process_one_work+0x9cc/0x18e0 worker_thread+0x5df/0xe40 kthread+0x3b8/0x730 ret_from_fork+0x3e9/0x560 ret_from_fork_asm+0x1a/0x30 </TASK> Allocated by task 29933: kasan_save_stack+0x30/0x50 kasan_save_track+0x14/0x30 __kasan_kmalloc+0x8f/0xa0 mlxsw_sp_mr_route_add+0xd8/0x4770 [mlxsw_spectrum] mlxsw_sp_router_fibmr_event_work+0x371/0xad0 drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c:7965 [mlxsw_spectrum] process_one_work+0x9cc/0x18e0 worker_thread+0x5df/0xe40 kthread+0x3b8/0x730 ret_from_fork+0x3e9/0x560 ret_from_fork_asm+0x1a/0x30 Freed by task 29933: kasan_save_stack+0x30/0x50 kasan_save_track+0x14/0x30 __kasan_save_free_info+0x3b/0x70 __kasan_slab_free+0x43/0x70 kfree+0x14e/0x700 mlxsw_sp_mr_route_add+0x2dea/0x4770 drivers/net/ethernet/mellanox/mlxsw/spectrum_mr.c:444 [mlxsw_spectrum] mlxsw_sp_router_fibmr_event_work+0x371/0xad0 drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c:7965 [mlxsw_spectrum] process_one_work+0x9cc/0x18e0 worker_thread+0x5df/0xe40 kthread+0x3b8/0x730 ret_from_fork+0x3e9/0x560 ret_from_fork_asm+0x1a/0x30 Fixes: f38656d06725 ("mlxsw: spectrum_mr: Protect multicast route list with a lock") Signed-off-by: Ido Schimmel <idosch(a)nvidia.com> Reviewed-by: Petr Machata <petrm(a)nvidia.com> Signed-off-by: Petr Machata <petrm(a)nvidia.com> Reviewed-by: Simon Horman <horms(a)kernel.org> Link: https://patch.msgid.link/f996feecfd59fde297964bfc85040b6d83ec6089.176469565… Signed-off-by: Jakub Kicinski <kuba(a)kernel.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Cai Xinchen <caixinchen1(a)huawei.com> --- drivers/net/ethernet/mellanox/mlxsw/spectrum_mr.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_mr.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_mr.c index ee308d9aedcd..d8a4bbb8e899 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_mr.c +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_mr.c @@ -440,7 +440,9 @@ int mlxsw_sp_mr_route_add(struct mlxsw_sp_mr_table *mr_table, rhashtable_remove_fast(&mr_table->route_ht, &mr_orig_route->ht_node, mlxsw_sp_mr_route_ht_params); + mutex_lock(&mr_table->route_list_lock); list_del(&mr_orig_route->node); + mutex_unlock(&mr_table->route_list_lock); mlxsw_sp_mr_route_destroy(mr_table, mr_orig_route); } -- 2.34.1

2 1

[PATCH OLK-6.6] memcg: avoid the warning in mem_cgroup_migrate
by Chen Ridong 27 Jan '26

27 Jan '26

hulk inclusion category: bugfix bugzilla: https://atomgit.com/openeuler/kernel/issues/7679 -------------------------------- For a hugetlb folio, the memcg may be null, which will lead to warning, To avoid warning, add !folio_test_hugetlb(old). The mem_cgroup_replace_folio is only used by fuse or shmem, the !folio_test_hugetlb(old) is unnecessary, remove it and keep the same with mainline. Fixes: d151025ac030 ("hugetlb: memcg: account hugetlb-backed memory in memory controller") Signed-off-by: Chen Ridong <chenridong(a)huawei.com> --- mm/memcontrol.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 45352cee74b18..51b438146ceef 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -8803,12 +8803,7 @@ void mem_cgroup_replace_folio(struct folio *old, struct folio *new) return; memcg = folio_memcg(old); - /* - * Note that it is normal to see !memcg for a hugetlb folio. - * For e.g, itt could have been allocated when memory_hugetlb_accounting - * was not selected. - */ - VM_WARN_ON_ONCE_FOLIO(!folio_test_hugetlb(old) && !memcg, old); + VM_WARN_ON_ONCE_FOLIO(!memcg, old); if (!memcg) return; @@ -8852,7 +8847,12 @@ void mem_cgroup_migrate(struct folio *old, struct folio *new) return; memcg = folio_memcg(old); - VM_WARN_ON_ONCE_FOLIO(!memcg, old); + /* + * Note that it is normal to see !memcg for a hugetlb folio. + * For e.g, itt could have been allocated when memory_hugetlb_accounting + * was not selected. + */ + VM_WARN_ON_ONCE_FOLIO(!folio_test_hugetlb(old) && !memcg, old); if (!memcg) return; -- 2.34.1

2 1

[PATCH OLK-5.10 0/2] Fix CVE-2025-37947
by Long Li 27 Jan '26

27 Jan '26

Fix CVE-2025-37947 Namjae Jeon (1): ksmbd: fix stream write failure Norbert Szetei (1): ksmbd: prevent out-of-bounds stream writes by validating *pos fs/ksmbd/vfs.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) -- 2.39.2

2 3

[PATCH OLK-6.6] s390/pci: Avoid deadlock between PCI error recovery and mlx5 crdump
by Zhang Yuwei 27 Jan '26

27 Jan '26

From: Gerd Bayer <gbayer(a)linux.ibm.com> stable inclusion from stable-v6.6.117 commit b63c061be622b17b495cbf78a6d5f2d4c3147f8e category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/11503 CVE: CVE-2025-68310 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit 0fd20f65df6aa430454a0deed8f43efa91c54835 ] Do not block PCI config accesses through pci_cfg_access_lock() when executing the s390 variant of PCI error recovery: Acquire just device_lock() instead of pci_dev_lock() as powerpc's EEH and generig PCI AER processing do. During error recovery testing a pair of tasks was reported to be hung: mlx5_core 0000:00:00.1: mlx5_health_try_recover:338:(pid 5553): health recovery flow aborted, PCI reads still not working INFO: task kmcheck:72 blocked for more than 122 seconds. Not tainted 5.14.0-570.12.1.bringup7.el9.s390x #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kmcheck state:D stack:0 pid:72 tgid:72 ppid:2 flags:0x00000000 Call Trace: [<000000065256f030>] __schedule+0x2a0/0x590 [<000000065256f356>] schedule+0x36/0xe0 [<000000065256f572>] schedule_preempt_disabled+0x22/0x30 [<0000000652570a94>] __mutex_lock.constprop.0+0x484/0x8a8 [<000003ff800673a4>] mlx5_unload_one+0x34/0x58 [mlx5_core] [<000003ff8006745c>] mlx5_pci_err_detected+0x94/0x140 [mlx5_core] [<0000000652556c5a>] zpci_event_attempt_error_recovery+0xf2/0x398 [<0000000651b9184a>] __zpci_event_error+0x23a/0x2c0 INFO: task kworker/u1664:6:1514 blocked for more than 122 seconds. Not tainted 5.14.0-570.12.1.bringup7.el9.s390x #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u1664:6 state:D stack:0 pid:1514 tgid:1514 ppid:2 flags:0x00000000 Workqueue: mlx5_health0000:00:00.0 mlx5_fw_fatal_reporter_err_work [mlx5_core] Call Trace: [<000000065256f030>] __schedule+0x2a0/0x590 [<000000065256f356>] schedule+0x36/0xe0 [<0000000652172e28>] pci_wait_cfg+0x80/0xe8 [<0000000652172f94>] pci_cfg_access_lock+0x74/0x88 [<000003ff800916b6>] mlx5_vsc_gw_lock+0x36/0x178 [mlx5_core] [<000003ff80098824>] mlx5_crdump_collect+0x34/0x1c8 [mlx5_core] [<000003ff80074b62>] mlx5_fw_fatal_reporter_dump+0x6a/0xe8 [mlx5_core] [<0000000652512242>] devlink_health_do_dump.part.0+0x82/0x168 [<0000000652513212>] devlink_health_report+0x19a/0x230 [<000003ff80075a12>] mlx5_fw_fatal_reporter_err_work+0xba/0x1b0 [mlx5_core] No kernel log of the exact same error with an upstream kernel is available - but the very same deadlock situation can be constructed there, too: - task: kmcheck mlx5_unload_one() tries to acquire devlink lock while the PCI error recovery code has set pdev->block_cfg_access by way of pci_cfg_access_lock() - task: kworker mlx5_crdump_collect() tries to set block_cfg_access through pci_cfg_access_lock() while devlink_health_report() had acquired the devlink lock. A similar deadlock situation can be reproduced by requesting a crdump with > devlink health dump show pci/<BDF> reporter fw_fatal while PCI error recovery is executed on the same <BDF> physical function by mlx5_core's pci_error_handlers. On s390 this can be injected with > zpcictl --reset-fw <BDF> Tests with this patch failed to reproduce that second deadlock situation, the devlink command is rejected with "kernel answers: Permission denied" - and we get a kernel log message of: mlx5_core 1ed0:00:00.1: mlx5_crdump_collect:50:(pid 254382): crdump: failed to lock vsc gw err -5 because the config read of VSC_SEMAPHORE is rejected by the underlying hardware. Two prior attempts to address this issue have been discussed and ultimately rejected [see link], with the primary argument that s390's implementation of PCI error recovery is imposing restrictions that neither powerpc's EEH nor PCI AER handling need. Tests show that PCI error recovery on s390 is running to completion even without blocking access to PCI config space. Link: https://lore.kernel.org/all/20251007144826.2825134-1-gbayer@linux.ibm.com/ Cc: stable(a)vger.kernel.org Fixes: 4cdf2f4e24ff ("s390/pci: implement minimal PCI error recovery") Reviewed-by: Niklas Schnelle <schnelle(a)linux.ibm.com> Signed-off-by: Gerd Bayer <gbayer(a)linux.ibm.com> Signed-off-by: Heiko Carstens <hca(a)linux.ibm.com> [ Adjust context ] Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Wang Hai <wanghai38(a)huawei.com> --- arch/s390/pci/pci_event.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/s390/pci/pci_event.c b/arch/s390/pci/pci_event.c index 3291241806bb..4cb77079ef2d 100644 --- a/arch/s390/pci/pci_event.c +++ b/arch/s390/pci/pci_event.c @@ -176,7 +176,7 @@ static pci_ers_result_t zpci_event_attempt_error_recovery(struct pci_dev *pdev) * is unbound or probed and that userspace can't access its * configuration space while we perform recovery. */ - pci_dev_lock(pdev); + device_lock(&pdev->dev); if (pdev->error_state == pci_channel_io_perm_failure) { ers_res = PCI_ERS_RESULT_DISCONNECT; goto out_unlock; @@ -224,7 +224,7 @@ static pci_ers_result_t zpci_event_attempt_error_recovery(struct pci_dev *pdev) if (driver->err_handler->resume) driver->err_handler->resume(pdev); out_unlock: - pci_dev_unlock(pdev); + device_unlock(&pdev->dev); return ers_res; } -- 2.22.0

2 1

[PATCH OLK-5.10] s390/pci: Avoid deadlock between PCI error recovery and mlx5 crdump
by Zhang Yuwei 27 Jan '26

27 Jan '26

From: Gerd Bayer <gbayer(a)linux.ibm.com> stable inclusion from stable-v6.6.117 commit b63c061be622b17b495cbf78a6d5f2d4c3147f8e category: bugfix bugzilla: https://atomgit.com/openeuler/kernel/issues/8287 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit 0fd20f65df6aa430454a0deed8f43efa91c54835 ] Do not block PCI config accesses through pci_cfg_access_lock() when executing the s390 variant of PCI error recovery: Acquire just device_lock() instead of pci_dev_lock() as powerpc's EEH and generig PCI AER processing do. During error recovery testing a pair of tasks was reported to be hung: mlx5_core 0000:00:00.1: mlx5_health_try_recover:338:(pid 5553): health recovery flow aborted, PCI reads still not working INFO: task kmcheck:72 blocked for more than 122 seconds. Not tainted 5.14.0-570.12.1.bringup7.el9.s390x #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kmcheck state:D stack:0 pid:72 tgid:72 ppid:2 flags:0x00000000 Call Trace: [<000000065256f030>] __schedule+0x2a0/0x590 [<000000065256f356>] schedule+0x36/0xe0 [<000000065256f572>] schedule_preempt_disabled+0x22/0x30 [<0000000652570a94>] __mutex_lock.constprop.0+0x484/0x8a8 [<000003ff800673a4>] mlx5_unload_one+0x34/0x58 [mlx5_core] [<000003ff8006745c>] mlx5_pci_err_detected+0x94/0x140 [mlx5_core] [<0000000652556c5a>] zpci_event_attempt_error_recovery+0xf2/0x398 [<0000000651b9184a>] __zpci_event_error+0x23a/0x2c0 INFO: task kworker/u1664:6:1514 blocked for more than 122 seconds. Not tainted 5.14.0-570.12.1.bringup7.el9.s390x #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u1664:6 state:D stack:0 pid:1514 tgid:1514 ppid:2 flags:0x00000000 Workqueue: mlx5_health0000:00:00.0 mlx5_fw_fatal_reporter_err_work [mlx5_core] Call Trace: [<000000065256f030>] __schedule+0x2a0/0x590 [<000000065256f356>] schedule+0x36/0xe0 [<0000000652172e28>] pci_wait_cfg+0x80/0xe8 [<0000000652172f94>] pci_cfg_access_lock+0x74/0x88 [<000003ff800916b6>] mlx5_vsc_gw_lock+0x36/0x178 [mlx5_core] [<000003ff80098824>] mlx5_crdump_collect+0x34/0x1c8 [mlx5_core] [<000003ff80074b62>] mlx5_fw_fatal_reporter_dump+0x6a/0xe8 [mlx5_core] [<0000000652512242>] devlink_health_do_dump.part.0+0x82/0x168 [<0000000652513212>] devlink_health_report+0x19a/0x230 [<000003ff80075a12>] mlx5_fw_fatal_reporter_err_work+0xba/0x1b0 [mlx5_core] No kernel log of the exact same error with an upstream kernel is available - but the very same deadlock situation can be constructed there, too: - task: kmcheck mlx5_unload_one() tries to acquire devlink lock while the PCI error recovery code has set pdev->block_cfg_access by way of pci_cfg_access_lock() - task: kworker mlx5_crdump_collect() tries to set block_cfg_access through pci_cfg_access_lock() while devlink_health_report() had acquired the devlink lock. A similar deadlock situation can be reproduced by requesting a crdump with > devlink health dump show pci/<BDF> reporter fw_fatal while PCI error recovery is executed on the same <BDF> physical function by mlx5_core's pci_error_handlers. On s390 this can be injected with > zpcictl --reset-fw <BDF> Tests with this patch failed to reproduce that second deadlock situation, the devlink command is rejected with "kernel answers: Permission denied" - and we get a kernel log message of: mlx5_core 1ed0:00:00.1: mlx5_crdump_collect:50:(pid 254382): crdump: failed to lock vsc gw err -5 because the config read of VSC_SEMAPHORE is rejected by the underlying hardware. Two prior attempts to address this issue have been discussed and ultimately rejected [see link], with the primary argument that s390's implementation of PCI error recovery is imposing restrictions that neither powerpc's EEH nor PCI AER handling need. Tests show that PCI error recovery on s390 is running to completion even without blocking access to PCI config space. Link: https://lore.kernel.org/all/20251007144826.2825134-1-gbayer@linux.ibm.com/ Cc: stable(a)vger.kernel.org Fixes: 4cdf2f4e24ff ("s390/pci: implement minimal PCI error recovery") Reviewed-by: Niklas Schnelle <schnelle(a)linux.ibm.com> Signed-off-by: Gerd Bayer <gbayer(a)linux.ibm.com> Signed-off-by: Heiko Carstens <hca(a)linux.ibm.com> [ Adjust context ] Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Wang Hai <wanghai38(a)huawei.com> --- arch/s390/pci/pci_event.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/s390/pci/pci_event.c b/arch/s390/pci/pci_event.c index 3291241806bb..4cb77079ef2d 100644 --- a/arch/s390/pci/pci_event.c +++ b/arch/s390/pci/pci_event.c @@ -176,7 +176,7 @@ static pci_ers_result_t zpci_event_attempt_error_recovery(struct pci_dev *pdev) * is unbound or probed and that userspace can't access its * configuration space while we perform recovery. */ - pci_dev_lock(pdev); + device_lock(&pdev->dev); if (pdev->error_state == pci_channel_io_perm_failure) { ers_res = PCI_ERS_RESULT_DISCONNECT; goto out_unlock; @@ -224,7 +224,7 @@ static pci_ers_result_t zpci_event_attempt_error_recovery(struct pci_dev *pdev) if (driver->err_handler->resume) driver->err_handler->resume(pdev); out_unlock: - pci_dev_unlock(pdev); + device_unlock(&pdev->dev); return ers_res; } -- 2.22.0

2 1

[PATCH OLK-6.6] KVM: SVM: Reject SEV{-ES} intra host migration if vCPU creation is in-flight
by Lin Ruifeng 27 Jan '26

27 Jan '26

From: Sean Christopherson <seanjc(a)google.com> stable inclusion from stable-v6.6.99 commit 8c8e8d4d7544bb783e15078eda8ba2580e192246 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/9350 CVE: CVE-2025-38455 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- commit ecf371f8b02d5e31b9aa1da7f159f1b2107bdb01 upstream. Reject migration of SEV{-ES} state if either the source or destination VM is actively creating a vCPU, i.e. if kvm_vm_ioctl_create_vcpu() is in the section between incrementing created_vcpus and online_vcpus. The bulk of vCPU creation runs _outside_ of kvm->lock to allow creating multiple vCPUs in parallel, and so sev_info.es_active can get toggled from false=>true in the destination VM after (or during) svm_vcpu_create(), resulting in an SEV{-ES} VM effectively having a non-SEV{-ES} vCPU. The issue manifests most visibly as a crash when trying to free a vCPU's NULL VMSA page in an SEV-ES VM, but any number of things can go wrong. BUG: unable to handle page fault for address: ffffebde00000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: Oops: 0000 [#1] SMP KASAN NOPTI CPU: 227 UID: 0 PID: 64063 Comm: syz.5.60023 Tainted: G U O 6.15.0-smp-DEV #2 NONE Tainted: [U]=USER, [O]=OOT_MODULE Hardware name: Google, Inc. Arcadia_IT_80/Arcadia_IT_80, BIOS 12.52.0-0 10/28/2024 RIP: 0010:constant_test_bit arch/x86/include/asm/bitops.h:206 [inline] RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:238 [inline] RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline] RIP: 0010:PageHead include/linux/page-flags.h:866 [inline] RIP: 0010:___free_pages+0x3e/0x120 mm/page_alloc.c:5067 Code: <49> f7 06 40 00 00 00 75 05 45 31 ff eb 0c 66 90 4c 89 f0 4c 39 f0 RSP: 0018:ffff8984551978d0 EFLAGS: 00010246 RAX: 0000777f80000001 RBX: 0000000000000000 RCX: ffffffff918aeb98 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffebde00000000 RBP: 0000000000000000 R08: ffffebde00000007 R09: 1ffffd7bc0000000 R10: dffffc0000000000 R11: fffff97bc0000001 R12: dffffc0000000000 R13: ffff8983e19751a8 R14: ffffebde00000000 R15: 1ffffd7bc0000000 FS: 0000000000000000(0000) GS:ffff89ee661d3000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffebde00000000 CR3: 000000793ceaa000 CR4: 0000000000350ef0 DR0: 0000000000000000 DR1: 0000000000000b5f DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: <TASK> sev_free_vcpu+0x413/0x630 arch/x86/kvm/svm/sev.c:3169 svm_vcpu_free+0x13a/0x2a0 arch/x86/kvm/svm/svm.c:1515 kvm_arch_vcpu_destroy+0x6a/0x1d0 arch/x86/kvm/x86.c:12396 kvm_vcpu_destroy virt/kvm/kvm_main.c:470 [inline] kvm_destroy_vcpus+0xd1/0x300 virt/kvm/kvm_main.c:490 kvm_arch_destroy_vm+0x636/0x820 arch/x86/kvm/x86.c:12895 kvm_put_kvm+0xb8e/0xfb0 virt/kvm/kvm_main.c:1310 kvm_vm_release+0x48/0x60 virt/kvm/kvm_main.c:1369 __fput+0x3e4/0x9e0 fs/file_table.c:465 task_work_run+0x1a9/0x220 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x7f0/0x25b0 kernel/exit.c:953 do_group_exit+0x203/0x2d0 kernel/exit.c:1102 get_signal+0x1357/0x1480 kernel/signal.c:3034 arch_do_signal_or_restart+0x40/0x690 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x67/0xb0 kernel/entry/common.c:218 do_syscall_64+0x7c/0x150 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f87a898e969 </TASK> Modules linked in: gq(O) gsmi: Log Shutdown Reason 0x03 CR2: ffffebde00000000 ---[ end trace 0000000000000000 ]--- Deliberately don't check for a NULL VMSA when freeing the vCPU, as crashing the host is likely desirable due to the VMSA being consumed by hardware. E.g. if KVM manages to allow VMRUN on the vCPU, hardware may read/write a bogus VMSA page. Accessing PFN 0 is "fine"-ish now that it's sequestered away thanks to L1TF, but panicking in this scenario is preferable to potentially running with corrupted state. Reported-by: Alexander Potapenko <glider(a)google.com> Tested-by: Alexander Potapenko <glider(a)google.com> Fixes: 0b020f5af092 ("KVM: SEV: Add support for SEV-ES intra host migration") Fixes: b56639318bb2 ("KVM: SEV: Add support for SEV intra host migration") Cc: stable(a)vger.kernel.org Cc: James Houghton <jthoughton(a)google.com> Cc: Peter Gonda <pgonda(a)google.com> Reviewed-by: Liam Merwick <liam.merwick(a)oracle.com> Tested-by: Liam Merwick <liam.merwick(a)oracle.com> Reviewed-by: James Houghton <jthoughton(a)google.com> Link: https://lore.kernel.org/r/20250602224459.41505-2-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc(a)google.com> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Lin Ruifeng <linruifeng4(a)huawei.com> --- arch/x86/kvm/svm/sev.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index 63611572ae10..9da6ce316dc4 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -1895,6 +1895,10 @@ static int sev_check_source_vcpus(struct kvm *dst, struct kvm *src) struct kvm_vcpu *src_vcpu; unsigned long i; + if (src->created_vcpus != atomic_read(&src->online_vcpus) || + dst->created_vcpus != atomic_read(&dst->online_vcpus)) + return -EBUSY; + if (!sev_es_guest(src)) return 0; -- 2.43.0

2 1

[PATCH OLK-6.6] atm: atmtcp: Prevent arbitrary write in atmtcp_recv_control().
by Lin Ruifeng 27 Jan '26

27 Jan '26

From: Kuniyuki Iwashima <kuniyu(a)google.com> stable inclusion from stable-v6.6.104 commit 3c80c230d6e3e6f63d43f4c3f0bb344e3e8b119b category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/12387 CVE: CVE-2025-39828 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit ec79003c5f9d2c7f9576fc69b8dbda80305cbe3a ] syzbot reported the splat below. [0] When atmtcp_v_open() or atmtcp_v_close() is called via connect() or close(), atmtcp_send_control() is called to send an in-kernel special message. The message has ATMTCP_HDR_MAGIC in atmtcp_control.hdr.length. Also, a pointer of struct atm_vcc is set to atmtcp_control.vcc. The notable thing is struct atmtcp_control is uAPI but has a space for an in-kernel pointer. struct atmtcp_control { struct atmtcp_hdr hdr; /* must be first */ ... atm_kptr_t vcc; /* both directions */ ... } __ATM_API_ALIGN; typedef struct { unsigned char _[8]; } __ATM_API_ALIGN atm_kptr_t; The special message is processed in atmtcp_recv_control() called from atmtcp_c_send(). atmtcp_c_send() is vcc->dev->ops->send() and called from 2 paths: 1. .ndo_start_xmit() (vcc->send() == atm_send_aal0()) 2. vcc_sendmsg() The problem is sendmsg() does not validate the message length and userspace can abuse atmtcp_recv_control() to overwrite any kptr by atmtcp_control. Let's add a new ->pre_send() hook to validate messages from sendmsg(). [0]: Oops: general protection fault, probably for non-canonical address 0xdffffc00200000ab: 0000 [#1] SMP KASAN PTI KASAN: probably user-memory-access in range [0x0000000100000558-0x000000010000055f] CPU: 0 UID: 0 PID: 5865 Comm: syz-executor331 Not tainted 6.17.0-rc1-syzkaller-00215-gbab3ce404553 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:atmtcp_recv_control drivers/atm/atmtcp.c:93 [inline] RIP: 0010:atmtcp_c_send+0x1da/0x950 drivers/atm/atmtcp.c:297 Code: 4d 8d 75 1a 4c 89 f0 48 c1 e8 03 42 0f b6 04 20 84 c0 0f 85 15 06 00 00 41 0f b7 1e 4d 8d b7 60 05 00 00 4c 89 f0 48 c1 e8 03 <42> 0f b6 04 20 84 c0 0f 85 13 06 00 00 66 41 89 1e 4d 8d 75 1c 4c RSP: 0018:ffffc90003f5f810 EFLAGS: 00010203 RAX: 00000000200000ab RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff88802a510000 RSI: 00000000ffffffff RDI: ffff888030a6068c RBP: ffff88802699fb40 R08: ffff888030a606eb R09: 1ffff1100614c0dd R10: dffffc0000000000 R11: ffffffff8718fc40 R12: dffffc0000000000 R13: ffff888030a60680 R14: 000000010000055f R15: 00000000ffffffff FS: 00007f8d7e9236c0(0000) GS:ffff888125c1c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000045ad50 CR3: 0000000075bde000 CR4: 00000000003526f0 Call Trace: <TASK> vcc_sendmsg+0xa10/0xc60 net/atm/common.c:645 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:729 ____sys_sendmsg+0x505/0x830 net/socket.c:2614 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668 __sys_sendmsg net/socket.c:2700 [inline] __do_sys_sendmsg net/socket.c:2705 [inline] __se_sys_sendmsg net/socket.c:2703 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2703 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8d7e96a4a9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 18 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f8d7e923198 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f8d7e9f4308 RCX: 00007f8d7e96a4a9 RDX: 0000000000000000 RSI: 0000200000000240 RDI: 0000000000000005 RBP: 00007f8d7e9f4300 R08: 65732f636f72702f R09: 65732f636f72702f R10: 65732f636f72702f R11: 0000000000000246 R12: 00007f8d7e9c10ac R13: 00007f8d7e9231a0 R14: 0000200000000200 R15: 0000200000000250 </TASK> Modules linked in: Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot+1741b56d54536f4ec349(a)syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/68a6767c.050a0220.3d78fd.0011.GAE@google.com/ Tested-by: syzbot+1741b56d54536f4ec349(a)syzkaller.appspotmail.com Signed-off-by: Kuniyuki Iwashima <kuniyu(a)google.com> Link: https://patch.msgid.link/20250821021901.2814721-1-kuniyu@google.com Signed-off-by: Jakub Kicinski <kuba(a)kernel.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Lin Ruifeng <linruifeng4(a)huawei.com> --- drivers/atm/atmtcp.c | 17 ++++++++++++++--- include/linux/atmdev.h | 1 + net/atm/common.c | 15 ++++++++++++--- 3 files changed, 27 insertions(+), 6 deletions(-) diff --git a/drivers/atm/atmtcp.c b/drivers/atm/atmtcp.c index ff558908897f..9c83fb29b2f1 100644 --- a/drivers/atm/atmtcp.c +++ b/drivers/atm/atmtcp.c @@ -279,6 +279,19 @@ static struct atm_vcc *find_vcc(struct atm_dev *dev, short vpi, int vci) return NULL; } +static int atmtcp_c_pre_send(struct atm_vcc *vcc, struct sk_buff *skb) +{ + struct atmtcp_hdr *hdr; + + if (skb->len < sizeof(struct atmtcp_hdr)) + return -EINVAL; + + hdr = (struct atmtcp_hdr *)skb->data; + if (hdr->length == ATMTCP_HDR_MAGIC) + return -EINVAL; + + return 0; +} static int atmtcp_c_send(struct atm_vcc *vcc,struct sk_buff *skb) { @@ -288,9 +301,6 @@ static int atmtcp_c_send(struct atm_vcc *vcc,struct sk_buff *skb) struct sk_buff *new_skb; int result = 0; - if (skb->len < sizeof(struct atmtcp_hdr)) - goto done; - dev = vcc->dev_data; hdr = (struct atmtcp_hdr *) skb->data; if (hdr->length == ATMTCP_HDR_MAGIC) { @@ -347,6 +357,7 @@ static const struct atmdev_ops atmtcp_v_dev_ops = { static const struct atmdev_ops atmtcp_c_dev_ops = { .close = atmtcp_c_close, + .pre_send = atmtcp_c_pre_send, .send = atmtcp_c_send }; diff --git a/include/linux/atmdev.h b/include/linux/atmdev.h index 45f2f278b50a..70807c679f1a 100644 --- a/include/linux/atmdev.h +++ b/include/linux/atmdev.h @@ -185,6 +185,7 @@ struct atmdev_ops { /* only send is required */ int (*compat_ioctl)(struct atm_dev *dev,unsigned int cmd, void __user *arg); #endif + int (*pre_send)(struct atm_vcc *vcc, struct sk_buff *skb); int (*send)(struct atm_vcc *vcc,struct sk_buff *skb); int (*send_bh)(struct atm_vcc *vcc, struct sk_buff *skb); int (*send_oam)(struct atm_vcc *vcc,void *cell,int flags); diff --git a/net/atm/common.c b/net/atm/common.c index 9cc82acbc735..48bb3f66a3f2 100644 --- a/net/atm/common.c +++ b/net/atm/common.c @@ -635,18 +635,27 @@ int vcc_sendmsg(struct socket *sock, struct msghdr *m, size_t size) skb->dev = NULL; /* for paths shared with net_device interfaces */ if (!copy_from_iter_full(skb_put(skb, size), size, &m->msg_iter)) { - atm_return_tx(vcc, skb); - kfree_skb(skb); error = -EFAULT; - goto out; + goto free_skb; } if (eff != size) memset(skb->data + size, 0, eff-size); + + if (vcc->dev->ops->pre_send) { + error = vcc->dev->ops->pre_send(vcc, skb); + if (error) + goto free_skb; + } + error = vcc->dev->ops->send(vcc, skb); error = error ? error : size; out: release_sock(sk); return error; +free_skb: + atm_return_tx(vcc, skb); + kfree_skb(skb); + goto out; } __poll_t vcc_poll(struct file *file, struct socket *sock, poll_table *wait) -- 2.43.0

2 1

[PATCH OLK-6.6] drm/mediatek: Disable AFBC support on Mediatek DRM driver
by Zhang Yuwei 27 Jan '26

27 Jan '26

From: Ariel D'Alessandro <ariel.dalessandro(a)collabora.com> stable inclusion from stable-v6.6.117 commit df1ad5de2197ea1b527d13ae7b699e9ee7d724d4 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/11625 CVE: CVE-2025-68184 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit 9882a40640036d5bbc590426a78981526d4f2345 ] Commit c410fa9b07c3 ("drm/mediatek: Add AFBC support to Mediatek DRM driver") added AFBC support to Mediatek DRM and enabled the 32x8/split/sparse modifier. However, this is currently broken on Mediatek MT8188 (Genio 700 EVK platform); tested using upstream Kernel and Mesa (v25.2.1), AFBC is used by default since Mesa v25.0. Kernel trace reports vblank timeouts constantly, and the render is garbled: ``` [CRTC:62:crtc-0] vblank wait timed out WARNING: CPU: 7 PID: 70 at drivers/gpu/drm/drm_atomic_helper.c:1835 drm_atomic_helper_wait_for_vblanks.part.0+0x24c/0x27c [...] Hardware name: MediaTek Genio-700 EVK (DT) Workqueue: events_unbound commit_work pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : drm_atomic_helper_wait_for_vblanks.part.0+0x24c/0x27c lr : drm_atomic_helper_wait_for_vblanks.part.0+0x24c/0x27c sp : ffff80008337bca0 x29: ffff80008337bcd0 x28: 0000000000000061 x27: 0000000000000000 x26: 0000000000000001 x25: 0000000000000000 x24: ffff0000c9dcc000 x23: 0000000000000001 x22: 0000000000000000 x21: ffff0000c66f2f80 x20: ffff0000c0d7d880 x19: 0000000000000000 x18: 000000000000000a x17: 000000040044ffff x16: 005000f2b5503510 x15: 0000000000000000 x14: 0000000000000000 x13: 74756f2064656d69 x12: 742074696177206b x11: 0000000000000058 x10: 0000000000000018 x9 : ffff800082396a70 x8 : 0000000000057fa8 x7 : 0000000000000cce x6 : ffff8000823eea70 x5 : ffff0001fef5f408 x4 : ffff80017ccee000 x3 : ffff0000c12cb480 x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff0000c12cb480 Call trace: drm_atomic_helper_wait_for_vblanks.part.0+0x24c/0x27c (P) drm_atomic_helper_commit_tail_rpm+0x64/0x80 commit_tail+0xa4/0x1a4 commit_work+0x14/0x20 process_one_work+0x150/0x290 worker_thread+0x2d0/0x3ec kthread+0x12c/0x210 ret_from_fork+0x10/0x20 ---[ end trace 0000000000000000 ]--- ``` Until this gets fixed upstream, disable AFBC support on this platform, as it's currently broken with upstream Mesa. Fixes: c410fa9b07c3 ("drm/mediatek: Add AFBC support to Mediatek DRM driver") Cc: stable(a)vger.kernel.org Signed-off-by: Ariel D'Alessandro <ariel.dalessandro(a)collabora.com> Reviewed-by: Daniel Stone <daniels(a)collabora.com> Reviewed-by: CK Hu <ck.hu(a)mediatek.com> Reviewed-by: Macpaul Lin <macpaul.lin(a)mediatek.com> Link: https://patchwork.kernel.org/project/dri-devel/patch/20251024202756.811425-… Signed-off-by: Chun-Kuang Hu <chunkuang.hu(a)kernel.org> [ Applied to mtk_drm_plane.c instead of mtk_plane.c ] Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Wang Hai <wanghai38(a)huawei.com> --- drivers/gpu/drm/mediatek/mtk_drm_plane.c | 24 +----------------------- 1 file changed, 1 insertion(+), 23 deletions(-) diff --git a/drivers/gpu/drm/mediatek/mtk_drm_plane.c b/drivers/gpu/drm/mediatek/mtk_drm_plane.c index f10d4cc6c223..32038cff2730 100644 --- a/drivers/gpu/drm/mediatek/mtk_drm_plane.c +++ b/drivers/gpu/drm/mediatek/mtk_drm_plane.c @@ -21,9 +21,6 @@ static const u64 modifiers[] = { DRM_FORMAT_MOD_LINEAR, - DRM_FORMAT_MOD_ARM_AFBC(AFBC_FORMAT_MOD_BLOCK_SIZE_32x8 | - AFBC_FORMAT_MOD_SPLIT | - AFBC_FORMAT_MOD_SPARSE), DRM_FORMAT_MOD_INVALID, }; @@ -71,26 +68,7 @@ static bool mtk_plane_format_mod_supported(struct drm_plane *plane, uint32_t format, uint64_t modifier) { - if (modifier == DRM_FORMAT_MOD_LINEAR) - return true; - - if (modifier != DRM_FORMAT_MOD_ARM_AFBC( - AFBC_FORMAT_MOD_BLOCK_SIZE_32x8 | - AFBC_FORMAT_MOD_SPLIT | - AFBC_FORMAT_MOD_SPARSE)) - return false; - - if (format != DRM_FORMAT_XRGB8888 && - format != DRM_FORMAT_ARGB8888 && - format != DRM_FORMAT_BGRX8888 && - format != DRM_FORMAT_BGRA8888 && - format != DRM_FORMAT_ABGR8888 && - format != DRM_FORMAT_XBGR8888 && - format != DRM_FORMAT_RGB888 && - format != DRM_FORMAT_BGR888) - return false; - - return true; + return modifier == DRM_FORMAT_MOD_LINEAR; } static void mtk_drm_plane_destroy_state(struct drm_plane *plane, -- 2.22.0

2 1

[PATCH OLK-6.6] drm/mediatek: Disable AFBC support on Mediatek DRM driver
by Zhang Yuwei 27 Jan '26

27 Jan '26

From: Ariel D'Alessandro <ariel.dalessandro(a)collabora.com> stable inclusion from stable-v6.6.117 commit df1ad5de2197ea1b527d13ae7b699e9ee7d724d4 category: bugfix bugzilla: https://atomgit.com/openeuler/kernel/issues/8287 CVE: CVE-2025-68184 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit 9882a40640036d5bbc590426a78981526d4f2345 ] Commit c410fa9b07c3 ("drm/mediatek: Add AFBC support to Mediatek DRM driver") added AFBC support to Mediatek DRM and enabled the 32x8/split/sparse modifier. However, this is currently broken on Mediatek MT8188 (Genio 700 EVK platform); tested using upstream Kernel and Mesa (v25.2.1), AFBC is used by default since Mesa v25.0. Kernel trace reports vblank timeouts constantly, and the render is garbled: ``` [CRTC:62:crtc-0] vblank wait timed out WARNING: CPU: 7 PID: 70 at drivers/gpu/drm/drm_atomic_helper.c:1835 drm_atomic_helper_wait_for_vblanks.part.0+0x24c/0x27c [...] Hardware name: MediaTek Genio-700 EVK (DT) Workqueue: events_unbound commit_work pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : drm_atomic_helper_wait_for_vblanks.part.0+0x24c/0x27c lr : drm_atomic_helper_wait_for_vblanks.part.0+0x24c/0x27c sp : ffff80008337bca0 x29: ffff80008337bcd0 x28: 0000000000000061 x27: 0000000000000000 x26: 0000000000000001 x25: 0000000000000000 x24: ffff0000c9dcc000 x23: 0000000000000001 x22: 0000000000000000 x21: ffff0000c66f2f80 x20: ffff0000c0d7d880 x19: 0000000000000000 x18: 000000000000000a x17: 000000040044ffff x16: 005000f2b5503510 x15: 0000000000000000 x14: 0000000000000000 x13: 74756f2064656d69 x12: 742074696177206b x11: 0000000000000058 x10: 0000000000000018 x9 : ffff800082396a70 x8 : 0000000000057fa8 x7 : 0000000000000cce x6 : ffff8000823eea70 x5 : ffff0001fef5f408 x4 : ffff80017ccee000 x3 : ffff0000c12cb480 x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff0000c12cb480 Call trace: drm_atomic_helper_wait_for_vblanks.part.0+0x24c/0x27c (P) drm_atomic_helper_commit_tail_rpm+0x64/0x80 commit_tail+0xa4/0x1a4 commit_work+0x14/0x20 process_one_work+0x150/0x290 worker_thread+0x2d0/0x3ec kthread+0x12c/0x210 ret_from_fork+0x10/0x20 ---[ end trace 0000000000000000 ]--- ``` Until this gets fixed upstream, disable AFBC support on this platform, as it's currently broken with upstream Mesa. Fixes: c410fa9b07c3 ("drm/mediatek: Add AFBC support to Mediatek DRM driver") Cc: stable(a)vger.kernel.org Signed-off-by: Ariel D'Alessandro <ariel.dalessandro(a)collabora.com> Reviewed-by: Daniel Stone <daniels(a)collabora.com> Reviewed-by: CK Hu <ck.hu(a)mediatek.com> Reviewed-by: Macpaul Lin <macpaul.lin(a)mediatek.com> Link: https://patchwork.kernel.org/project/dri-devel/patch/20251024202756.811425-… Signed-off-by: Chun-Kuang Hu <chunkuang.hu(a)kernel.org> [ Applied to mtk_drm_plane.c instead of mtk_plane.c ] Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Wang Hai <wanghai38(a)huawei.com> --- drivers/gpu/drm/mediatek/mtk_drm_plane.c | 24 +----------------------- 1 file changed, 1 insertion(+), 23 deletions(-) diff --git a/drivers/gpu/drm/mediatek/mtk_drm_plane.c b/drivers/gpu/drm/mediatek/mtk_drm_plane.c index f10d4cc6c223..32038cff2730 100644 --- a/drivers/gpu/drm/mediatek/mtk_drm_plane.c +++ b/drivers/gpu/drm/mediatek/mtk_drm_plane.c @@ -21,9 +21,6 @@ static const u64 modifiers[] = { DRM_FORMAT_MOD_LINEAR, - DRM_FORMAT_MOD_ARM_AFBC(AFBC_FORMAT_MOD_BLOCK_SIZE_32x8 | - AFBC_FORMAT_MOD_SPLIT | - AFBC_FORMAT_MOD_SPARSE), DRM_FORMAT_MOD_INVALID, }; @@ -71,26 +68,7 @@ static bool mtk_plane_format_mod_supported(struct drm_plane *plane, uint32_t format, uint64_t modifier) { - if (modifier == DRM_FORMAT_MOD_LINEAR) - return true; - - if (modifier != DRM_FORMAT_MOD_ARM_AFBC( - AFBC_FORMAT_MOD_BLOCK_SIZE_32x8 | - AFBC_FORMAT_MOD_SPLIT | - AFBC_FORMAT_MOD_SPARSE)) - return false; - - if (format != DRM_FORMAT_XRGB8888 && - format != DRM_FORMAT_ARGB8888 && - format != DRM_FORMAT_BGRX8888 && - format != DRM_FORMAT_BGRA8888 && - format != DRM_FORMAT_ABGR8888 && - format != DRM_FORMAT_XBGR8888 && - format != DRM_FORMAT_RGB888 && - format != DRM_FORMAT_BGR888) - return false; - - return true; + return modifier == DRM_FORMAT_MOD_LINEAR; } static void mtk_drm_plane_destroy_state(struct drm_plane *plane, -- 2.22.0

2 1

[PATCH OLK-6.6] nvme: fix admin request_queue lifetime
by Yifan Qiao 27 Jan '26

27 Jan '26

From: Keith Busch <kbusch(a)kernel.org> mainline inclusion from mainline-v6.18-rc7 commit 03b3bcd319b3ab5182bc9aaa0421351572c78ac0 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/11536 CVE: CVE-2025-68265 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- The namespaces can access the controller's admin request_queue, and stale references on the namespaces may exist after tearing down the controller. Ensure the admin request_queue is active by moving the controller's 'put' to after all controller references have been released to ensure no one is can access the request_queue. This fixes a reported use-after-free bug: BUG: KASAN: slab-use-after-free in blk_queue_enter+0x41c/0x4a0 Read of size 8 at addr ffff88c0a53819f8 by task nvme/3287 CPU: 67 UID: 0 PID: 3287 Comm: nvme Tainted: G E 6.13.2-ga1582f1a031e #15 Tainted: [E]=UNSIGNED_MODULE Hardware name: Jabil /EGS 2S MB1, BIOS 1.00 06/18/2025 Call Trace: <TASK> dump_stack_lvl+0x4f/0x60 print_report+0xc4/0x620 ? _raw_spin_lock_irqsave+0x70/0xb0 ? _raw_read_unlock_irqrestore+0x30/0x30 ? blk_queue_enter+0x41c/0x4a0 kasan_report+0xab/0xe0 ? blk_queue_enter+0x41c/0x4a0 blk_queue_enter+0x41c/0x4a0 ? __irq_work_queue_local+0x75/0x1d0 ? blk_queue_start_drain+0x70/0x70 ? irq_work_queue+0x18/0x20 ? vprintk_emit.part.0+0x1cc/0x350 ? wake_up_klogd_work_func+0x60/0x60 blk_mq_alloc_request+0x2b7/0x6b0 ? __blk_mq_alloc_requests+0x1060/0x1060 ? __switch_to+0x5b7/0x1060 nvme_submit_user_cmd+0xa9/0x330 nvme_user_cmd.isra.0+0x240/0x3f0 ? force_sigsegv+0xe0/0xe0 ? nvme_user_cmd64+0x400/0x400 ? vfs_fileattr_set+0x9b0/0x9b0 ? cgroup_update_frozen_flag+0x24/0x1c0 ? cgroup_leave_frozen+0x204/0x330 ? nvme_ioctl+0x7c/0x2c0 blkdev_ioctl+0x1a8/0x4d0 ? blkdev_common_ioctl+0x1930/0x1930 ? fdget+0x54/0x380 __x64_sys_ioctl+0x129/0x190 do_syscall_64+0x5b/0x160 entry_SYSCALL_64_after_hwframe+0x4b/0x53 RIP: 0033:0x7f765f703b0b Code: ff ff ff 85 c0 79 9b 49 c7 c4 ff ff ff ff 5b 5d 4c 89 e0 41 5c c3 66 0f 1f 84 00 00 00 00 00 f3 0f 1e fa b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d dd 52 0f 00 f7 d8 64 89 01 48 RSP: 002b:00007ffe2cefe808 EFLAGS: 00000202 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007ffe2cefe860 RCX: 00007f765f703b0b RDX: 00007ffe2cefe860 RSI: 00000000c0484e41 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000000 R10: 00007f765f611d50 R11: 0000000000000202 R12: 0000000000000003 R13: 00000000c0484e41 R14: 0000000000000001 R15: 00007ffe2cefea60 </TASK> Reported-by: Casey Chen <cachen(a)purestorage.com> Reviewed-by: Christoph Hellwig <hch(a)lst.de> Reviewed-by: Hannes Reinecke <hare(a)suse.de> Reviewed-by: Ming Lei <ming.lei(a)redhat.com> Reviewed-by: Chaitanya Kulkarni <kch(a)nvidia.com> Signed-off-by: Keith Busch <kbusch(a)kernel.org> Signed-off-by: Yifan Qiao <qiaoyifan4(a)huawei.com> --- drivers/nvme/host/core.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index 081f837f58d6..e79ff52ae0a0 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -4330,7 +4330,6 @@ EXPORT_SYMBOL_GPL(nvme_alloc_admin_tag_set); void nvme_remove_admin_tag_set(struct nvme_ctrl *ctrl) { blk_mq_destroy_queue(ctrl->admin_q); - blk_put_queue(ctrl->admin_q); if (ctrl->ops->flags & NVME_F_FABRICS) { blk_mq_destroy_queue(ctrl->fabrics_q); blk_put_queue(ctrl->fabrics_q); @@ -4469,6 +4468,8 @@ static void nvme_free_ctrl(struct device *dev) container_of(dev, struct nvme_ctrl, ctrl_device); struct nvme_subsystem *subsys = ctrl->subsys; + if (ctrl->admin_q) + blk_put_queue(ctrl->admin_q); if (!subsys || ctrl->instance != subsys->instance) ida_free(&nvme_instance_ida, ctrl->instance); -- 2.39.2

2 1

[PATCH OLK-5.10] um: virtio_uml: Fix use-after-free after put_device in probe
by Zhang Yuwei 27 Jan '26

27 Jan '26

From: Miaoqian Lin <linmq006(a)gmail.com> mainline inclusion from mainline-v6.17-rc7 commit 7ebf70cf181651fe3f2e44e95e7e5073d594c9c0 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/8206 CVE: CVE-2025-39951 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- When register_virtio_device() fails in virtio_uml_probe(), the code sets vu_dev->registered = 1 even though the device was not successfully registered. This can lead to use-after-free or other issues. Fixes: 04e5b1fb0183 ("um: virtio: Remove device on disconnect") Signed-off-by: Miaoqian Lin <linmq006(a)gmail.com> Signed-off-by: Johannes Berg <johannes.berg(a)intel.com> Conflicts: arch/um/drivers/virtio_uml.c [commit 1fcf9da38901 is not backport] Signed-off-by: Zhang Yuwei <zhangyuwei20(a)huawei.com> --- arch/um/drivers/virtio_uml.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/um/drivers/virtio_uml.c b/arch/um/drivers/virtio_uml.c index d5d768188b3b..0178d33e5946 100644 --- a/arch/um/drivers/virtio_uml.c +++ b/arch/um/drivers/virtio_uml.c @@ -1129,10 +1129,12 @@ static int virtio_uml_probe(struct platform_device *pdev) platform_set_drvdata(pdev, vu_dev); rc = register_virtio_device(&vu_dev->vdev); - if (rc) + if (rc) { put_device(&vu_dev->vdev.dev); + return rc; + } vu_dev->registered = 1; - return rc; + return 0; error_init: os_close_file(vu_dev->sock); -- 2.22.0

2 1

[PATCH OLK-5.10] um: virtio_uml: Fix use-after-free after put_device in probe
by Zhang Yuwei 27 Jan '26

27 Jan '26

From: Miaoqian Lin <linmq006(a)gmail.com> mainline inclusion from mainline-v6.17-rc7 commit 7ebf70cf181651fe3f2e44e95e7e5073d594c9c0 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/ID0U90 CVE: CVE-2025-39951 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- When register_virtio_device() fails in virtio_uml_probe(), the code sets vu_dev->registered = 1 even though the device was not successfully registered. This can lead to use-after-free or other issues. Fixes: 04e5b1fb0183 ("um: virtio: Remove device on disconnect") Signed-off-by: Miaoqian Lin <linmq006(a)gmail.com> Signed-off-by: Johannes Berg <johannes.berg(a)intel.com> Conflicts: arch/um/drivers/virtio_uml.c [commit 1fcf9da38901 is not backport] Signed-off-by: Zhang Yuwei <zhangyuwei20(a)huawei.com> --- arch/um/drivers/virtio_uml.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/um/drivers/virtio_uml.c b/arch/um/drivers/virtio_uml.c index d5d768188b3b..0178d33e5946 100644 --- a/arch/um/drivers/virtio_uml.c +++ b/arch/um/drivers/virtio_uml.c @@ -1129,10 +1129,12 @@ static int virtio_uml_probe(struct platform_device *pdev) platform_set_drvdata(pdev, vu_dev); rc = register_virtio_device(&vu_dev->vdev); - if (rc) + if (rc) { put_device(&vu_dev->vdev.dev); + return rc; + } vu_dev->registered = 1; - return rc; + return 0; error_init: os_close_file(vu_dev->sock); -- 2.22.0

2 1

[PATCH OLK-6.6 0/9] arm_mpam: Introduce the Narrow-PARTID feature for MPAM driver
by Zeng Heng 26 Jan '26

26 Jan '26

The narrow-partid feature in MPAM allows for a more efficient use of PARTIDs by enabling a many-to-one mapping of reqpartids (requested PARTIDs) to intpartids (internal PARTIDs). This mapping reduces the number of unique PARTIDs needed, thus allowing more tasks or processes to be monitored and managed with the available resources. For a mixture of MSCs system, for MSCs that do not support narrow-partid, we use the PARTIDs exceeding the number of closids as reqPARTIDs for expanding the monitoring groups. Therefore, we will expand the information contained in the RMID, so that it includes not only PMG, but also reqPARTIDs information. The new RMID would be like: RMID = (reqPARTID << shift | PMG). Each control group has m (req)PARTIDs, which are used to expand the number of monitoring groups under one control group. Therefore, the number of monitoring groups is no longer limited by the range of MPAM's PMG, which enhances the extensibility of the system's monitoring capabilities. Dave Martin (1): arm_mpam: Set INTERNAL as needed when setting MSC controls Zeng Heng (8): arm_mpam: Introduce the definitions of intPARTID and reqPARTID arm_mpam: Add limitation for the Narrow-PARTID feature arm_mpam: Expand the composition of RMID arm_mpam: Automatically synchronize the configuration of all sub-monitoring groups Revert "arm_mpam: Add limitation for the Narrow-PARTID feature" fs/resctrl: Add resctrl_arch_expand_rmid() fs/resctrl: Deploy resctrl_arch_expand_rmid() arm64/mpam: Add limitation arch/x86/include/asm/resctrl.h | 7 + drivers/platform/mpam/mpam_devices.c | 61 ++++- drivers/platform/mpam/mpam_internal.h | 5 + drivers/platform/mpam/mpam_resctrl.c | 355 ++++++++++++++++++++------ fs/resctrl/monitor.c | 45 +++- include/linux/arm_mpam.h | 16 ++ include/linux/resctrl.h | 18 ++ 7 files changed, 415 insertions(+), 92 deletions(-) -- 2.25.1

2 10

[PATCH OLK-6.6] ext4: fix stale data issue on the iomap path
by Yongjian Sun 26 Jan '26

26 Jan '26

Offering: HULK hulk inclusion category: bugfix bugzilla: https://atomgit.com/openeuler/kernel/issues/8430 -------------------------------- There is a stale data issue caused by merging 9e891675aab8. After the patch was merged, data writeback before punch hole cancellation was canceled. This led to some regions of unwritten extents not being zeroed, ultimately exposing stale data. Fixes: 9e891675aab8 ("ext4: don't write back data before punch hole in nojournal mode") Signed-off-by: Yongjian Sun <sunyongjian1(a)huawei.com> --- fs/ext4/inode.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 84a09f3e6d49..cc4eeccc0dd7 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -4696,13 +4696,12 @@ int ext4_punch_hole(struct file *file, loff_t offset, loff_t length) ret = ext4_update_disksize_before_punch(inode, offset, length); if (ret) goto out_dio; - - ret = ext4_truncate_page_cache_block_range(inode, - first_block_offset, last_block_offset + 1); - if (ret) - goto out_dio; } + ret = ext4_truncate_page_cache_block_range(inode, offset, offset + length); + if (ret) + goto out_dio; + if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) credits = ext4_writepage_trans_blocks(inode); else -- 2.39.2

2 1

[PATCH OLK-6.6] [Backport] tpm: Cap the number of PCR banks
by Chen Jinghuang 26 Jan '26

26 Jan '26

From: Jarkko Sakkinen <jarkko.sakkinen(a)opinsys.com> stable inclusion from stable-v6.6.120 commit d88481653d74d622d1d0d2c9bad845fc2cc6fd23 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/13388 CVE: CVE-2025-71077 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- commit faf07e611dfa464b201223a7253e9dc5ee0f3c9e upstream. tpm2_get_pcr_allocation() does not cap any upper limit for the number of banks. Cap the limit to eight banks so that out of bounds values coming from external I/O cause on only limited harm. Cc: stable(a)vger.kernel.org # v5.10+ Fixes: bcfff8384f6c ("tpm: dynamically allocate the allocated_banks array") Tested-by: Lai Yi <yi1.lai(a)linux.intel.com> Reviewed-by: Jonathan McDowell <noodles(a)meta.com> Reviewed-by: Roberto Sassu <roberto.sassu(a)huawei.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen(a)opinsys.com> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Chen Jinghuang <chenjinghuang2(a)huawei.com> --- drivers/char/tpm/tpm-chip.c | 1 - drivers/char/tpm/tpm1-cmd.c | 5 ----- drivers/char/tpm/tpm2-cmd.c | 8 +++----- include/linux/tpm.h | 8 +++++--- 4 files changed, 8 insertions(+), 14 deletions(-) diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c index 70e3fe20fdcf..458a3e9ea73a 100644 --- a/drivers/char/tpm/tpm-chip.c +++ b/drivers/char/tpm/tpm-chip.c @@ -279,7 +279,6 @@ static void tpm_dev_release(struct device *dev) kfree(chip->work_space.context_buf); kfree(chip->work_space.session_buf); - kfree(chip->allocated_banks); kfree(chip); } diff --git a/drivers/char/tpm/tpm1-cmd.c b/drivers/char/tpm/tpm1-cmd.c index cf64c7385105..b49a790f1bd5 100644 --- a/drivers/char/tpm/tpm1-cmd.c +++ b/drivers/char/tpm/tpm1-cmd.c @@ -799,11 +799,6 @@ int tpm1_pm_suspend(struct tpm_chip *chip, u32 tpm_suspend_pcr) */ int tpm1_get_pcr_allocation(struct tpm_chip *chip) { - chip->allocated_banks = kcalloc(1, sizeof(*chip->allocated_banks), - GFP_KERNEL); - if (!chip->allocated_banks) - return -ENOMEM; - chip->allocated_banks[0].alg_id = TPM_ALG_SHA1; chip->allocated_banks[0].digest_size = hash_digest_size[HASH_ALGO_SHA1]; chip->allocated_banks[0].crypto_id = HASH_ALGO_SHA1; diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c index 93545be190a5..57bb3e34b770 100644 --- a/drivers/char/tpm/tpm2-cmd.c +++ b/drivers/char/tpm/tpm2-cmd.c @@ -574,11 +574,9 @@ ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip) nr_possible_banks = be32_to_cpup( (__be32 *)&buf.data[TPM_HEADER_SIZE + 5]); - - chip->allocated_banks = kcalloc(nr_possible_banks, - sizeof(*chip->allocated_banks), - GFP_KERNEL); - if (!chip->allocated_banks) { + if (nr_possible_banks > TPM2_MAX_PCR_BANKS) { + pr_err("tpm: out of bank capacity: %u > %u\n", + nr_possible_banks, TPM2_MAX_PCR_BANKS); rc = -ENOMEM; goto out; } diff --git a/include/linux/tpm.h b/include/linux/tpm.h index bf8a4ec8a01c..f5e7cca2f257 100644 --- a/include/linux/tpm.h +++ b/include/linux/tpm.h @@ -25,7 +25,9 @@ #include <crypto/hash_info.h> #define TPM_DIGEST_SIZE 20 /* Max TPM v1.2 PCR size */ -#define TPM_MAX_DIGEST_SIZE SHA512_DIGEST_SIZE + +#define TPM2_MAX_DIGEST_SIZE SHA512_DIGEST_SIZE +#define TPM2_MAX_PCR_BANKS 8 struct tpm_chip; struct trusted_key_payload; @@ -51,7 +53,7 @@ enum tpm_algorithms { struct tpm_digest { u16 alg_id; - u8 digest[TPM_MAX_DIGEST_SIZE]; + u8 digest[TPM2_MAX_DIGEST_SIZE]; } __packed; struct tpm_bank_info { @@ -157,7 +159,7 @@ struct tpm_chip { unsigned int groups_cnt; u32 nr_allocated_banks; - struct tpm_bank_info *allocated_banks; + struct tpm_bank_info allocated_banks[TPM2_MAX_PCR_BANKS]; #ifdef CONFIG_ACPI acpi_handle acpi_dev_handle; char ppi_version[TPM_PPI_VERSION_LEN + 1]; -- 2.34.1

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[PATCH OLK-5.10] mm/kmemleak: move up cond_resched() call in page scanning loop
by Wupeng Ma 26 Jan '26

26 Jan '26

From: Waiman Long <longman(a)redhat.com> mainline inclusion from mainline-v6.6-rc1 commit e68d343d2720779362cb7160cb7f4bd24979b2b4 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/8429 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- Commit bde5f6bc68db ("kmemleak: add scheduling point to kmemleak_scan()") added a cond_resched() call to the struct page scanning loop to prevent soft lockup from happening. However, soft lockup can still happen in that loop in some corner cases when the pages that satisfy the "!(pfn & 63)" check are skipped for some reasons. Fix this corner case by moving up the cond_resched() check so that it will be called every 64 pages unconditionally. Link: https://lkml.kernel.org/r/20230825164947.1317981-1-longman@redhat.com Fixes: bde5f6bc68db ("kmemleak: add scheduling point to kmemleak_scan()") Signed-off-by: Waiman Long <longman(a)redhat.com> Cc: Catalin Marinas <catalin.marinas(a)arm.com> Cc: Yisheng Xie <xieyisheng1(a)huawei.com> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> Signed-off-by: Wupeng Ma <mawupeng1(a)huawei.com> --- mm/kmemleak.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/mm/kmemleak.c b/mm/kmemleak.c index 90eb82299149d..1d9ea3901d472 100644 --- a/mm/kmemleak.c +++ b/mm/kmemleak.c @@ -1456,6 +1456,9 @@ static void kmemleak_scan(void) for (pfn = start_pfn; pfn < end_pfn; pfn++) { struct page *page = pfn_to_online_page(pfn); + if (!(pfn & 63)) + cond_resched(); + if (!page) continue; @@ -1466,8 +1469,6 @@ static void kmemleak_scan(void) if (page_count(page) == 0) continue; scan_block(page, page + 1, NULL); - if (!(pfn & 63)) - cond_resched(); } } put_online_mems(); -- 2.43.0

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[PATCH OLK-6.6 0/2] CVE-2026-22980
by Li Lingfeng 26 Jan '26

26 Jan '26

Fix CVE-2026-22980. Li Lingfeng (1): Revert "nfsd: provide locking for v4_end_grace" NeilBrown (1): nfsd: provide locking for v4_end_grace fs/nfsd/nfs4state.c | 25 +++++++++++++++++++------ 1 file changed, 19 insertions(+), 6 deletions(-) -- 2.52.0

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