April 2024 - Kernel - mailweb.openeuler.org

[PATCH OLK-5.10 0/5] CVE-2024-26921
by Ziyang Xuan 28 Apr '24

28 Apr '24

Patchset of CVE-2024-26921. Florian Westphal (1): inet: inet_defrag: prevent sk release while still in use Vasily Averin (2): skbuff: introduce skb_expand_head() skb_expand_head() adjust skb->truesize incorrectly Ziyang Xuan (2): net: Fix KABI break for introducing is_skb_wmem() sk_buff: Fix KABI break for the modification of struct sk_buff include/linux/skbuff.h | 1 + include/net/tcp.h | 2 +- include/net/tcp_ext.h | 14 +++++ net/core/skbuff.c | 52 ++++++++++++++++++ net/ipv4/inet_fragment.c | 70 ++++++++++++++++++++----- net/ipv4/ip_fragment.c | 2 +- net/ipv6/netfilter/nf_conntrack_reasm.c | 2 +- 7 files changed, 127 insertions(+), 16 deletions(-) create mode 100644 include/net/tcp_ext.h -- 2.25.1

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[PATCH OLK-5.10 0/5] Apply patches of ses from stable
by Li Lingfeng 28 Apr '24

28 Apr '24

Jiri Kosina (1): scsi: ses: Handle enclosure with just a primary component gracefully Li Lingfeng (3): Revert "scsi: ses: fix slab-out-of-bounds in ses_enclosure_data_process" Revert "scsi: ses: Fix crash caused by kfree an invalid pointer" Revert "scsi: ses: Handle enclosure with just a primary component gracefully" Tomas Henzl (1): scsi: ses: Fix possible desc_ptr out-of-bounds accesses drivers/scsi/ses.c | 21 ++++++++++++--------- 1 file changed, 12 insertions(+), 9 deletions(-) -- 2.31.1

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[PATCH OLK-5.10 0/2] olk-5.10: bugfix for mm
by Wupeng Ma 28 Apr '24

28 Apr '24

From: Ma Wupeng <mawupeng1(a)huawei.com> backport minor bugfix for mm. Mel Gorman (1): mm/page_alloc: always attempt to allocate at least one page during bulk allocation Miaohe Lin (1): mm/madvise: fix potential pte_unmap_unlock pte error mm/madvise.c | 8 ++++---- mm/page_alloc.c | 7 ++++--- 2 files changed, 8 insertions(+), 7 deletions(-) -- 2.25.1

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[PATCH OLK-5.10] NFSv4.2: fix nfs4_listxattr kernel BUG at mm/usercopy.c:102
by Long Li 28 Apr '24

28 Apr '24

From: Jorge Mora <jmora1300(a)gmail.com> stable inclusion from stable-v5.10.167 commit 4403438eaca6e91f02d272211c4d6b045092396b category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9HK78 CVE: CVE-2024-26870 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=… -------------------------------- [ Upstream commit 251a658bbfceafb4d58c76b77682c8bf7bcfad65 ] A call to listxattr() with a buffer size = 0 returns the actual size of the buffer needed for a subsequent call. When size > 0, nfs4_listxattr() does not return an error because either generic_listxattr() or nfs4_listxattr_nfs4_label() consumes exactly all the bytes then size is 0 when calling nfs4_listxattr_nfs4_user() which then triggers the following kernel BUG: [ 99.403778] kernel BUG at mm/usercopy.c:102! [ 99.404063] Internal error: Oops - BUG: 00000000f2000800 [#1] SMP [ 99.408463] CPU: 0 PID: 3310 Comm: python3 Not tainted 6.6.0-61.fc40.aarch64 #1 [ 99.415827] Call trace: [ 99.415985] usercopy_abort+0x70/0xa0 [ 99.416227] __check_heap_object+0x134/0x158 [ 99.416505] check_heap_object+0x150/0x188 [ 99.416696] __check_object_size.part.0+0x78/0x168 [ 99.416886] __check_object_size+0x28/0x40 [ 99.417078] listxattr+0x8c/0x120 [ 99.417252] path_listxattr+0x78/0xe0 [ 99.417476] __arm64_sys_listxattr+0x28/0x40 [ 99.417723] invoke_syscall+0x78/0x100 [ 99.417929] el0_svc_common.constprop.0+0x48/0xf0 [ 99.418186] do_el0_svc+0x24/0x38 [ 99.418376] el0_svc+0x3c/0x110 [ 99.418554] el0t_64_sync_handler+0x120/0x130 [ 99.418788] el0t_64_sync+0x194/0x198 [ 99.418994] Code: aa0003e3 d000a3e0 91310000 97f49bdb (d4210000) Issue is reproduced when generic_listxattr() returns 'system.nfs4_acl', thus calling lisxattr() with size = 16 will trigger the bug. Add check on nfs4_listxattr() to return ERANGE error when it is called with size > 0 and the return value is greater than size. Fixes: 012a211abd5d ("NFSv4.2: hook in the user extended attribute handlers") Signed-off-by: Jorge Mora <mora(a)netapp.com> Reviewed-by: Benjamin Coddington <bcodding(a)redhat.com> Signed-off-by: Trond Myklebust <trond.myklebust(a)hammerspace.com> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Long Li <leo.lilong(a)huawei.com> --- fs/nfs/nfs4proc.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index f3f41027f697..62c227eb75bd 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -10367,29 +10367,33 @@ const struct nfs4_minor_version_ops *nfs_v4_minor_ops[] = { static ssize_t nfs4_listxattr(struct dentry *dentry, char *list, size_t size) { ssize_t error, error2, error3; + size_t left = size; - error = generic_listxattr(dentry, list, size); + error = generic_listxattr(dentry, list, left); if (error < 0) return error; if (list) { list += error; - size -= error; + left -= error; } - error2 = nfs4_listxattr_nfs4_label(d_inode(dentry), list, size); + error2 = nfs4_listxattr_nfs4_label(d_inode(dentry), list, left); if (error2 < 0) return error2; if (list) { list += error2; - size -= error2; + left -= error2; } - error3 = nfs4_listxattr_nfs4_user(d_inode(dentry), list, size); + error3 = nfs4_listxattr_nfs4_user(d_inode(dentry), list, left); if (error3 < 0) return error3; - return error + error2 + error3; + error += error2 + error3; + if (size && error > size) + return -ERANGE; + return error; } static void nfs4_enable_swap(struct inode *inode) -- 2.31.1

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[PATCH OLK-5.10 0/8] cvm feature patches
by hejingxian 28 Apr '24

28 Apr '24

From: Jingxian He <hejingxian(a)huawei.com> Add cvm feature patches:: kvm: add cvm host feature pmu: enable pmu phys irq inject for cvm kvm: add support for multi-numa and fix kabi change swiotlb: Add restricted DMA alloc/free support swiotlb: add swiotlb io_tlb_list release slots methd mm: enable swiotlb alloc for cvm share mem config: modify arm64 defconfig for cvm feature gicv3: add lpi support for cvm guest arch/arm64/Kconfig | 8 + arch/arm64/configs/defconfig | 3 + arch/arm64/configs/openeuler_defconfig | 3 + arch/arm64/include/asm/Kbuild | 1 - arch/arm64/include/asm/cvm_guest.h | 46 ++ arch/arm64/include/asm/kvm_emulate.h | 18 + arch/arm64/include/asm/kvm_host.h | 28 +- arch/arm64/include/asm/kvm_tmi.h | 377 +++++++++++ arch/arm64/include/asm/kvm_tmm.h | 73 ++ arch/arm64/include/asm/set_memory.h | 9 + arch/arm64/kernel/Makefile | 1 + arch/arm64/kernel/cvm_guest.c | 93 +++ arch/arm64/kvm/Kconfig | 7 + arch/arm64/kvm/Makefile | 4 + arch/arm64/kvm/arch_timer.c | 104 ++- arch/arm64/kvm/arm.c | 157 ++++- arch/arm64/kvm/cvm.c | 892 +++++++++++++++++++++++++ arch/arm64/kvm/cvm_exit.c | 240 +++++++ arch/arm64/kvm/guest.c | 8 + arch/arm64/kvm/hisilicon/hisi_virt.c | 7 + arch/arm64/kvm/hyp/vgic-v3-sr.c | 19 + arch/arm64/kvm/mmio.c | 19 + arch/arm64/kvm/mmu.c | 7 + arch/arm64/kvm/pmu-emul.c | 12 + arch/arm64/kvm/psci.c | 12 +- arch/arm64/kvm/reset.c | 10 + arch/arm64/kvm/tmi.c | 168 +++++ arch/arm64/kvm/vgic/vgic-v3.c | 18 +- arch/arm64/kvm/vgic/vgic.c | 59 +- arch/arm64/mm/init.c | 3 + arch/arm64/mm/mmu.c | 6 +- arch/arm64/mm/pageattr.c | 3 + drivers/irqchip/irq-gic-v3-its.c | 229 ++++++- drivers/perf/arm_pmu.c | 17 + include/kvm/arm_arch_timer.h | 4 + include/linux/kvm_host.h | 23 + include/linux/perf/arm_pmu.h | 3 + include/linux/swiotlb.h | 17 + include/uapi/linux/kvm.h | 27 + kernel/dma/Kconfig | 10 + kernel/dma/direct.c | 56 +- kernel/dma/swiotlb.c | 92 +++ virt/kvm/kvm_main.c | 7 +- 43 files changed, 2843 insertions(+), 57 deletions(-) create mode 100644 arch/arm64/include/asm/cvm_guest.h create mode 100644 arch/arm64/include/asm/kvm_tmi.h create mode 100644 arch/arm64/include/asm/kvm_tmm.h create mode 100644 arch/arm64/include/asm/set_memory.h create mode 100644 arch/arm64/kernel/cvm_guest.c create mode 100644 arch/arm64/kvm/cvm.c create mode 100644 arch/arm64/kvm/cvm_exit.c create mode 100644 arch/arm64/kvm/tmi.c -- 2.33.0

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[PATCH openEuler-1.0-LTS] drm/bridge: adv7511: fix crash on irq during probe
by Zhao Wenhui 27 Apr '24

27 Apr '24

From: Mads Bligaard Nielsen <bli(a)bang-olufsen.dk> mainline inclusion from mainline-v6.9-rc1 commit aeedaee5ef5468caf59e2bb1265c2116e0c9a924 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9HKEE CVE: CVE-2024-26876 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- Moved IRQ registration down to end of adv7511_probe(). If an IRQ already is pending during adv7511_probe (before adv7511_cec_init) then cec_received_msg_ts could crash using uninitialized data: Unable to handle kernel read from unreadable memory at virtual address 00000000000003d5 Internal error: Oops: 96000004 [#1] PREEMPT_RT SMP Call trace: cec_received_msg_ts+0x48/0x990 [cec] adv7511_cec_irq_process+0x1cc/0x308 [adv7511] adv7511_irq_process+0xd8/0x120 [adv7511] adv7511_irq_handler+0x1c/0x30 [adv7511] irq_thread_fn+0x30/0xa0 irq_thread+0x14c/0x238 kthread+0x190/0x1a8 Fixes: 3b1b975003e4 ("drm: adv7511/33: add HDMI CEC support") Signed-off-by: Mads Bligaard Nielsen <bli(a)bang-olufsen.dk> Signed-off-by: Alvin Šipraga <alsi(a)bang-olufsen.dk> Reviewed-by: Robert Foss <rfoss(a)kernel.org> Signed-off-by: Robert Foss <rfoss(a)kernel.org> Link: https://patchwork.freedesktop.org/patch/msgid/20240219-adv7511-cec-irq-cras… Conflicts: drivers/gpu/drm/bridge/adv7511/adv7511_drv.c Signed-off-by: Zhao Wenhui <zhaowenhui8(a)huawei.com> --- drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 23 ++++++++++---------- 1 file changed, 12 insertions(+), 11 deletions(-) diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c index e7ddd3e3db92..31bce3a37b20 100644 --- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c +++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c @@ -1194,17 +1194,6 @@ static int adv7511_probe(struct i2c_client *i2c, const struct i2c_device_id *id) INIT_WORK(&adv7511->hpd_work, adv7511_hpd_work); - if (i2c->irq) { - init_waitqueue_head(&adv7511->wq); - - ret = devm_request_threaded_irq(dev, i2c->irq, NULL, - adv7511_irq_handler, - IRQF_ONESHOT, dev_name(dev), - adv7511); - if (ret) - goto err_unregister_cec; - } - adv7511_power_off(adv7511); i2c_set_clientdata(i2c, adv7511); @@ -1222,6 +1211,18 @@ static int adv7511_probe(struct i2c_client *i2c, const struct i2c_device_id *id) drm_bridge_add(&adv7511->bridge); adv7511_audio_init(dev, adv7511); + + if (i2c->irq) { + init_waitqueue_head(&adv7511->wq); + + ret = devm_request_threaded_irq(dev, i2c->irq, NULL, + adv7511_irq_handler, + IRQF_ONESHOT, dev_name(dev), + adv7511); + if (ret) + goto err_unregister_cec; + } + return 0; err_unregister_cec: -- 2.34.1

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[PATCH OLK-5.10 0/8] cvm feature patches
by hejingxian 27 Apr '24

27 Apr '24

From: Jingxian He <hejingxian(a)huawei.com> Add cvm feature patches:: kvm: add cvm host feature pmu: enable pmu phys irq inject for cvm kvm: add support for multi-numa and fix kabi change swiotlb: Add restricted DMA alloc/free support swiotlb: add swiotlb io_tlb_list release slots methd mm: enable swiotlb alloc for cvm share mem config: modify arm64 defconfig for cvm featue gicv3: add lpi support for cvm guest arch/arm64/Kconfig | 8 + arch/arm64/configs/defconfig | 3 + arch/arm64/configs/openeuler_defconfig | 3 + arch/arm64/include/asm/Kbuild | 1 - arch/arm64/include/asm/cvm_guest.h | 46 ++ arch/arm64/include/asm/kvm_emulate.h | 18 + arch/arm64/include/asm/kvm_host.h | 28 +- arch/arm64/include/asm/kvm_tmi.h | 377 +++++++++++ arch/arm64/include/asm/kvm_tmm.h | 73 ++ arch/arm64/include/asm/set_memory.h | 9 + arch/arm64/kernel/Makefile | 1 + arch/arm64/kernel/cvm_guest.c | 93 +++ arch/arm64/kvm/Kconfig | 7 + arch/arm64/kvm/Makefile | 4 + arch/arm64/kvm/arch_timer.c | 104 ++- arch/arm64/kvm/arm.c | 157 ++++- arch/arm64/kvm/cvm.c | 892 +++++++++++++++++++++++++ arch/arm64/kvm/cvm_exit.c | 240 +++++++ arch/arm64/kvm/guest.c | 8 + arch/arm64/kvm/hisilicon/hisi_virt.c | 7 + arch/arm64/kvm/hyp/vgic-v3-sr.c | 19 + arch/arm64/kvm/mmio.c | 19 + arch/arm64/kvm/mmu.c | 7 + arch/arm64/kvm/pmu-emul.c | 12 + arch/arm64/kvm/psci.c | 12 +- arch/arm64/kvm/reset.c | 10 + arch/arm64/kvm/tmi.c | 168 +++++ arch/arm64/kvm/vgic/vgic-v3.c | 18 +- arch/arm64/kvm/vgic/vgic.c | 59 +- arch/arm64/mm/init.c | 3 + arch/arm64/mm/mmu.c | 6 +- arch/arm64/mm/pageattr.c | 3 + drivers/irqchip/irq-gic-v3-its.c | 229 ++++++- drivers/perf/arm_pmu.c | 17 + include/kvm/arm_arch_timer.h | 4 + include/linux/kvm_host.h | 23 + include/linux/perf/arm_pmu.h | 3 + include/linux/swiotlb.h | 17 + include/uapi/linux/kvm.h | 27 + kernel/dma/Kconfig | 10 + kernel/dma/direct.c | 56 +- kernel/dma/swiotlb.c | 92 +++ virt/kvm/kvm_main.c | 7 +- 43 files changed, 2843 insertions(+), 57 deletions(-) create mode 100644 arch/arm64/include/asm/cvm_guest.h create mode 100644 arch/arm64/include/asm/kvm_tmi.h create mode 100644 arch/arm64/include/asm/kvm_tmm.h create mode 100644 arch/arm64/include/asm/set_memory.h create mode 100644 arch/arm64/kernel/cvm_guest.c create mode 100644 arch/arm64/kvm/cvm.c create mode 100644 arch/arm64/kvm/cvm_exit.c create mode 100644 arch/arm64/kvm/tmi.c -- 2.33.0

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[PATCH openEuler-1.0-LTS V1] sched/rt: Disallow writing invalid values to sched_rt_period_us
by Cheng Yu 27 Apr '24

27 Apr '24

From: Cyril Hrubis <chrubis(a)suse.cz> stable inclusion from stable-v4.19.308 commit 2d931472d4740d3ada7011cc4c3499948d3a22fa category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I9K4JZ Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=… -------------------------------- [ Upstream commit 079be8fc630943d9fc70a97807feb73d169ee3fc ] The validation of the value written to sched_rt_period_us was broken because: - the sysclt_sched_rt_period is declared as unsigned int - parsed by proc_do_intvec() - the range is asserted after the value parsed by proc_do_intvec() Because of this negative values written to the file were written into a unsigned integer that were later on interpreted as large positive integers which did passed the check: if (sysclt_sched_rt_period <= 0) return EINVAL; This commit fixes the parsing by setting explicit range for both perid_us and runtime_us into the sched_rt_sysctls table and processes the values with proc_dointvec_minmax() instead. Alternatively if we wanted to use full range of unsigned int for the period value we would have to split the proc_handler and use proc_douintvec() for it however even the Documentation/scheduller/sched-rt-group.rst describes the range as 1 to INT_MAX. As far as I can tell the only problem this causes is that the sysctl file allows writing negative values which when read back may confuse userspace. There is also a LTP test being submitted for these sysctl files at: http://patchwork.ozlabs.org/project/ltp/patch/20230901144433.2526-1-chrubis… Signed-off-by: Cyril Hrubis <chrubis(a)suse.cz> Signed-off-by: Ingo Molnar <mingo(a)kernel.org> Link: https://lore.kernel.org/r/20231002115553.3007-2-chrubis@suse.cz [ pvorel: rebased for 4.19 ] Reviewed-by: Petr Vorel <pvorel(a)suse.cz> Signed-off-by: Petr Vorel <pvorel(a)suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Conflicts: kernel/sysctl.c Signed-off-by: Cheng Yu <serein.chengyu(a)huawei.com> --- kernel/sched/rt.c | 5 +---- kernel/sysctl.c | 5 +++++ 2 files changed, 6 insertions(+), 4 deletions(-) diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 5dff9a6fe2cf..724a31e0b2a3 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -2655,9 +2655,6 @@ static int sched_rt_global_constraints(void) static int sched_rt_global_validate(void) { - if (sysctl_sched_rt_period <= 0) - return -EINVAL; - if ((sysctl_sched_rt_runtime != RUNTIME_INF) && (sysctl_sched_rt_runtime > sysctl_sched_rt_period)) return -EINVAL; @@ -2687,7 +2684,7 @@ int sched_rt_handler(struct ctl_table *table, int write, old_period = sysctl_sched_rt_period; old_runtime = sysctl_sched_rt_runtime; - ret = proc_dointvec(table, write, buffer, lenp, ppos); + ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); if (!ret && write) { ret = sched_rt_global_validate(); diff --git a/kernel/sysctl.c b/kernel/sysctl.c index c7064f67f4a5..f64c4495bc54 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -131,6 +131,7 @@ static int __maybe_unused three = 3; static int __maybe_unused four = 4; static int __maybe_unused five = 5; static int __maybe_unused uce_kernel_recovery_max = 31; +static int int_max = INT_MAX; static unsigned long zero_ul; static unsigned long one_ul = 1; static unsigned long long_max = LONG_MAX; @@ -463,6 +464,8 @@ static struct ctl_table kern_table[] = { .maxlen = sizeof(unsigned int), .mode = 0644, .proc_handler = sched_rt_handler, + .extra1 = &one, + .extra2 = &int_max, }, { .procname = "sched_rt_runtime_us", @@ -470,6 +473,8 @@ static struct ctl_table kern_table[] = { .maxlen = sizeof(int), .mode = 0644, .proc_handler = sched_rt_handler, + .extra1 = &neg_one, + .extra2 = &int_max, }, { .procname = "sched_rr_timeslice_ms", -- 2.25.1

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[PATCH openEuler-1.0-LTS V1] sched/rt: sysctl_sched_rr_timeslice show default timeslice after reset
by Cheng Yu 27 Apr '24

27 Apr '24

From: Cyril Hrubis <chrubis(a)suse.cz> stable inclusion from stable-v4.19.308 commit 1f80bc015277247c9fd9646f7c21f1c728b5d908 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I9K4H3 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=… -------------------------------- [ Upstream commit c1fc6484e1fb7cc2481d169bfef129a1b0676abe ] The sched_rr_timeslice can be reset to default by writing value that is <= 0. However after reading from this file we always got the last value written, which is not useful at all. $ echo -1 > /proc/sys/kernel/sched_rr_timeslice_ms $ cat /proc/sys/kernel/sched_rr_timeslice_ms -1 Fix this by setting the variable that holds the sysctl file value to the jiffies_to_msecs(RR_TIMESLICE) in case that <= 0 value was written. Signed-off-by: Cyril Hrubis <chrubis(a)suse.cz> Signed-off-by: Peter Zijlstra (Intel) <peterz(a)infradead.org> Reviewed-by: Petr Vorel <pvorel(a)suse.cz> Acked-by: Mel Gorman <mgorman(a)suse.de> Tested-by: Petr Vorel <pvorel(a)suse.cz> Link: https://lore.kernel.org/r/20230802151906.25258-3-chrubis@suse.cz Signed-off-by: Petr Vorel <pvorel(a)suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Cheng Yu <serein.chengyu(a)huawei.com> --- kernel/sched/rt.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 5dff9a6fe2cf..d98adf048bb6 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -2732,6 +2732,9 @@ int sched_rr_handler(struct ctl_table *table, int write, sched_rr_timeslice = sysctl_sched_rr_timeslice <= 0 ? RR_TIMESLICE : msecs_to_jiffies(sysctl_sched_rr_timeslice); + + if (sysctl_sched_rr_timeslice <= 0) + sysctl_sched_rr_timeslice = jiffies_to_msecs(RR_TIMESLICE); } mutex_unlock(&mutex); -- 2.25.1

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[PATCH openEuler-1.0-LTS V1] sched/rt: Fix sysctl_sched_rr_timeslice intial value
by Cheng Yu 27 Apr '24

27 Apr '24

From: Cyril Hrubis <chrubis(a)suse.cz> stable inclusion from stable-v4.19.308 commit 41b7572dea9f7196d075b40d5ac8aafdb5f4b0d4 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I9K34B Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=… -------------------------------- [ Upstream commit c7fcb99877f9f542c918509b2801065adcaf46fa ] There is a 10% rounding error in the intial value of the sysctl_sched_rr_timeslice with CONFIG_HZ_300=y. This was found with LTP test sched_rr_get_interval01: sched_rr_get_interval01.c:57: TPASS: sched_rr_get_interval() passed sched_rr_get_interval01.c:64: TPASS: Time quantum 0s 99999990ns sched_rr_get_interval01.c:72: TFAIL: /proc/sys/kernel/sched_rr_timeslice_ms != 100 got 90 sched_rr_get_interval01.c:57: TPASS: sched_rr_get_interval() passed sched_rr_get_interval01.c:64: TPASS: Time quantum 0s 99999990ns sched_rr_get_interval01.c:72: TFAIL: /proc/sys/kernel/sched_rr_timeslice_ms != 100 got 90 What this test does is to compare the return value from the sched_rr_get_interval() and the sched_rr_timeslice_ms sysctl file and fails if they do not match. The problem it found is the intial sysctl file value which was computed as: static int sysctl_sched_rr_timeslice = (MSEC_PER_SEC / HZ) * RR_TIMESLICE; which works fine as long as MSEC_PER_SEC is multiple of HZ, however it introduces 10% rounding error for CONFIG_HZ_300: (MSEC_PER_SEC / HZ) * (100 * HZ / 1000) (1000 / 300) * (100 * 300 / 1000) 3 * 30 = 90 This can be easily fixed by reversing the order of the multiplication and division. After this fix we get: (MSEC_PER_SEC * (100 * HZ / 1000)) / HZ (1000 * (100 * 300 / 1000)) / 300 (1000 * 30) / 300 = 100 Fixes: 975e155ed873 ("sched/rt: Show the 'sched_rr_timeslice' SCHED_RR timeslice tuning knob in milliseconds") Signed-off-by: Cyril Hrubis <chrubis(a)suse.cz> Signed-off-by: Peter Zijlstra (Intel) <peterz(a)infradead.org> Reviewed-by: Petr Vorel <pvorel(a)suse.cz> Acked-by: Mel Gorman <mgorman(a)suse.de> Tested-by: Petr Vorel <pvorel(a)suse.cz> Link: https://lore.kernel.org/r/20230802151906.25258-2-chrubis@suse.cz [ pvorel: rebased for 4.19 ] Signed-off-by: Petr Vorel <pvorel(a)suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Cheng Yu <serein.chengyu(a)huawei.com> --- kernel/sched/rt.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 5dff9a6fe2cf..7f66f28d36a8 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -8,7 +8,7 @@ #include "pelt.h" int sched_rr_timeslice = RR_TIMESLICE; -int sysctl_sched_rr_timeslice = (MSEC_PER_SEC / HZ) * RR_TIMESLICE; +int sysctl_sched_rr_timeslice = (MSEC_PER_SEC * RR_TIMESLICE) / HZ; static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun); -- 2.25.1

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