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[PATCH OLK-6.6 0/1] Fix TLBI broadcast optimization loss and incorrect dvmbm handling
by Tian Zheng 13 Mar '26

13 Mar '26

Fix 1 In the TLBI broadcast-optimization feature, the SYS_LSUDVM_CTRL_EL2 register controls whether the feature is enabled. When LPI low-power mode is enabled, this register is cleared as the pCPU powers down into LPI mode, causing the TLBI broadcast optimization to stop working. The fix saves and restores this control register in the callbacks for entering and exiting LPI mode. Fix 2 The current TLBI broadcast-optimization logic only supports normal VMs. If the feature is enabled globally, VMs that are not yet adapted for it, such as CCA will use an incorrect TLBI broadcast bitmap, which can cause a panic in CCA VMs. The fix moves the actual enable/disable of the dvmbm functionality into the vcpu load and vcpu put functions. Tian Zheng (1): KVM: arm64: Fix CCA guest panic when dvmbm is enabled arch/arm64/kvm/hisilicon/hisi_virt.c | 18 ++++++------------ 1 file changed, 6 insertions(+), 12 deletions(-) -- 2.33.0

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[PATCH v13 00/12] arm64: entry: Convert to Generic Entry
by Jinjie Ruan 13 Mar '26

13 Mar '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 v7.0-rc1. And the performance was measured on Kunpeng 920 using "perf bench basic syscall" with "arm64.nopauth selinux=0 audit=1". On the basis of optimizing el0_svc_common(), 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: - Stress-ng CPU stress test. - Hackbench stress test. - "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 \ Changes in v13: - Rebased on v7.0-rc3, so drop the firt applied arm64 patch. - Use generic TIF bits to enables RSEQ optimization. - Update most of the commit message to make it more clear. - Link to v12: https://lore.kernel.org/all/20260203133728.848283-5-ruanjinjie@huawei.com/ Changes in v12: - Rebased on "sched/core", so remove the four generic entry patches. - Move "Expand secure_computing() in place" and "Use syscall_get_arguments() helper" patch forward, which will group all non-functional cleanups at the front. - Adjust the explanation for moving rseq_syscall() before audit_syscall_exit(). - Link to v11: https://lore.kernel.org/all/20260128031934.3906955-1-ruanjinjie@huawei.com/ 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/ Jinjie Ruan (11): arm64/ptrace: Refactor syscall_trace_enter/exit() to accept flags parameter arm64/ptrace: Expand secure_computing() in place arm64/ptrace: Use syscall_get_arguments() helper for audit arm64: ptrace: Move rseq_syscall() before audit_syscall_exit() arm64: syscall: Introduce syscall_exit_to_user_mode_work() arm64/ptrace: Define and use _TIF_SYSCALL_EXIT_WORK arm64/ptrace: Skip syscall exit reporting for PTRACE_SYSEMU_SINGLESTEP arm64: entry: Convert to generic entry arm64: Inline el0_svc_common() s390: Rename TIF_SINGLE_STEP to TIF_SINGLESTEP arm64: Use generic TIF bits for common thread flags kemal (1): selftests: sud_test: Support aarch64 arch/arm64/Kconfig | 3 +- arch/arm64/include/asm/entry-common.h | 76 ++++++++++++ arch/arm64/include/asm/syscall.h | 19 ++- arch/arm64/include/asm/thread_info.h | 76 ++++-------- 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 ++--- arch/s390/include/asm/thread_info.h | 7 +- arch/s390/kernel/process.c | 2 +- arch/s390/kernel/ptrace.c | 20 +-- arch/s390/kernel/signal.c | 6 +- arch/x86/include/asm/thread_info.h | 6 +- include/asm-generic/thread_info_tif.h | 5 + .../syscall_user_dispatch/sud_benchmark.c | 2 +- .../syscall_user_dispatch/sud_test.c | 4 + 16 files changed, 166 insertions(+), 213 deletions(-) -- 2.34.1

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[PATCH v3 00/10] arm_mpam: Introduce the Narrow-PARTID feature for MPAM driver
by Zeng Heng 13 Mar '26

13 Mar '26

The patchset is based on mpam_resctrl_glue_v5_debugfs branch of https://gitlab.arm.com/linux-arm/linux-bh.git repository. 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 * NUM_PMG + 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. --- Compared with v2: - Add dynamic reqPARTID allocation implementation. - Patch 4 has been merged into the repository, dropped from this series. Compared with v1: - Redefine the RMID information. - Refactor the resctrl_arch_rmid_idx_decode() and resctrl_arch_rmid_idx_encode(). - Simplify closid_rmid2reqpartid() to rmid2reqpartid() and replace it accordingly. Compared with RFC-v4: - Rebase the patch set on the v6.14-rc1 branch. Compared with RFC-v3: - Add limitation of the Narrow-PARTID feature (See Patch 2). - Remove redundant reqpartid2closid() and reqpartid_pmg2rmid(). - Refactor closid_rmid2reqpartid() partially. - Merge the PARTID conversion-related patches into a single patch for bisectability. - Skip adaptation of resctrl_arch_set_rmid() which is going to be removed. Compared with RFC-v2: - Refactor closid/rmid pair translation. - Simplify the logic of synchronize configuration. - Remove reqPARTID source bitmap. Compared with RFC-v1: - Rebase this patch set on latest MPAM driver of the v6.12-rc1 branch. v2: https://lore.kernel.org/all/20250222112448.2438586-1-zengheng4@huawei.com/ v1: https://lore.kernel.org/all/20250217031852.2014939-1-zengheng4@huawei.com/ RFC-v4: https://lore.kernel.org/all/20250104101224.873926-1-zengheng4@huawei.com/ RFC-v3: https://lore.kernel.org/all/20241207092136.2488426-1-zengheng4@huawei.com/ RFC-v2: https://lore.kernel.org/all/20241119135104.595630-1-zengheng4@huawei.com/ RFC-v1: https://lore.kernel.org/all/20241114135037.918470-1-zengheng4@huawei.com/ --- Ben Horgan (1): arm64/sysreg: Add MPAMSM_EL1 register Zeng Heng (9): arm_mpam: Add intPARTID and reqPARTID support for narrow PARTID feature arm_mpam: Disable Narrow-PARTID when MBA lacks support arm_mpam: Refactor rmid to reqPARTID/PMG mapping arm_mpam: Propagate control group config to sub-monitoring groups fs/resctrl: Add rmid_entry state helpers arm_mpam: Implement dynamic reqPARTID allocation for monitoring groups fs/resctrl: Wire up rmid expansion and reclaim functions arm64/mpam: Add mpam_sync_config() for dynamic rmid expansion fs/resctrl: Prevent rmid parsing errors by flushing limbo on umount Documentation/arch/arm64/index.rst | 1 + Documentation/arch/arm64/mpam.rst | 94 + Documentation/arch/arm64/silicon-errata.rst | 9 + arch/arm64/Kconfig | 6 +- arch/arm64/include/asm/el2_setup.h | 3 +- arch/arm64/include/asm/mpam.h | 96 + arch/arm64/include/asm/resctrl.h | 2 + arch/arm64/include/asm/thread_info.h | 3 + arch/arm64/kernel/Makefile | 1 + arch/arm64/kernel/cpufeature.c | 21 +- arch/arm64/kernel/mpam.c | 62 + arch/arm64/kernel/process.c | 7 + arch/arm64/kvm/hyp/include/hyp/switch.h | 12 +- arch/arm64/kvm/hyp/nvhe/hyp-main.c | 9 + arch/arm64/kvm/hyp/vhe/sysreg-sr.c | 16 + arch/arm64/kvm/sys_regs.c | 2 + arch/arm64/tools/sysreg | 8 + arch/x86/include/asm/resctrl.h | 7 + drivers/resctrl/Kconfig | 9 +- drivers/resctrl/Makefile | 1 + drivers/resctrl/mpam_devices.c | 340 ++- drivers/resctrl/mpam_internal.h | 112 +- drivers/resctrl/mpam_resctrl.c | 2094 +++++++++++++++++++ drivers/resctrl/test_mpam_resctrl.c | 364 ++++ fs/resctrl/monitor.c | 50 +- fs/resctrl/rdtgroup.c | 24 +- include/linux/arm_mpam.h | 49 + include/linux/resctrl.h | 21 + 28 files changed, 3368 insertions(+), 55 deletions(-) create mode 100644 Documentation/arch/arm64/mpam.rst create mode 100644 arch/arm64/include/asm/mpam.h create mode 100644 arch/arm64/include/asm/resctrl.h create mode 100644 arch/arm64/kernel/mpam.c create mode 100644 drivers/resctrl/mpam_resctrl.c create mode 100644 drivers/resctrl/test_mpam_resctrl.c -- 2.25.1

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[PATCH OLK-6.6] arm64/mpam: Fix warning of schedule state in resctrl_arch_mon_ctx_alloc()
by Zeng Heng 13 Mar '26

13 Mar '26

hulk inclusion category: bugfix bugzilla: https://atomgit.com/openeuler/kernel/issues/8686 ------------------ resctrl_arch_mon_ctx_alloc() triggers a scheduling state warning when calling kmalloc() while the task is in a non-running state: do not call blocking ops when !TASK_RUNNING; state=1 set at prepare_to_wait WARNING: CPU: 78 PID: 12592 at kernel/sched/core.c:10584 _might_sleep Call trace: _might_sleep+0x1cc/0xf8 _kmalloc_cache_alloc_node+0x3a0/0x4e0 kmalloc_trace+0x44/0x120 resctrl_arch_mon_ctx_alloc+0xf0/0x178 mon_event_read+0xa0/0x308 mkdir_mondata_subdir+0x24c/0x330 mkdir_mondata_all+0x17c/0x248 rdt_get_tree+0x2e8/0x680 vfs_get_tree+0x5c/0x190 do_new_mount+0x27c/0x408 path_mount+0x2ac/0x448 arm64_sys_mount+0x1d4/0x228 Ensure the allocation is performed in TASK_RUNNING state to avoid schedule state corrupted. Fixes: 9119da143939 ("arm_mpam: resctrl: Allow resctrl to allocate monitors") Signed-off-by: Zeng Heng <zengheng4(a)huawei.com> --- drivers/platform/mpam/mpam_resctrl.c | 25 +++---------------------- 1 file changed, 3 insertions(+), 22 deletions(-) diff --git a/drivers/platform/mpam/mpam_resctrl.c b/drivers/platform/mpam/mpam_resctrl.c index 1a26a0ed2cff..b6681f328aaa 100644 --- a/drivers/platform/mpam/mpam_resctrl.c +++ b/drivers/platform/mpam/mpam_resctrl.c @@ -388,11 +388,11 @@ struct rdt_resource *resctrl_arch_get_resource(enum resctrl_res_level l) return &mpam_resctrl_exports[l].resctrl_res; } -static void *resctrl_arch_mon_ctx_alloc_no_wait(struct rdt_resource *r, - int evtid) +void *resctrl_arch_mon_ctx_alloc(struct rdt_resource *r, int evtid) { - u32 *ret = kmalloc(sizeof(*ret), GFP_KERNEL); + u32 *ret; + ret = kmalloc(sizeof(*ret), GFP_KERNEL); if (!ret) return ERR_PTR(-ENOMEM); @@ -400,25 +400,6 @@ static void *resctrl_arch_mon_ctx_alloc_no_wait(struct rdt_resource *r, return ret; } -void *resctrl_arch_mon_ctx_alloc(struct rdt_resource *r, int evtid) -{ - DEFINE_WAIT(wait); - void *ret; - - might_sleep(); - - do { - prepare_to_wait(&resctrl_mon_ctx_waiters, &wait, - TASK_INTERRUPTIBLE); - ret = resctrl_arch_mon_ctx_alloc_no_wait(r, evtid); - if (PTR_ERR(ret) == -ENOSPC) - schedule(); - } while (PTR_ERR(ret) == -ENOSPC && !signal_pending(current)); - finish_wait(&resctrl_mon_ctx_waiters, &wait); - - return ret; -} - void resctrl_arch_mon_ctx_free(struct rdt_resource *r, int evtid, void *arch_mon_ctx) { -- 2.25.1

2 1

[PATCH OLK-6.6] selftests/bpf: Add cross-build support for urandom_read et al
by Pu Lehui 12 Mar '26

12 Mar '26

From: Björn Töpel <bjorn(a)rivosinc.com> mainline inclusion from mainline-v6.7-rc1 commit 97a79e502e25e27a65b0506c9fb210cb2d89b52e category: bugfix bugzilla: https://atomgit.com/openeuler/kernel/issues/8638 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- Some userland programs in the BPF test suite, e.g. urandom_read, is missing cross-build support. Add cross-build support for these programs Signed-off-by: Björn Töpel <bjorn(a)rivosinc.com> Signed-off-by: Andrii Nakryiko <andrii(a)kernel.org> Link: https://lore.kernel.org/bpf/20231004122721.54525-2-bjorn@kernel.org Conflicts: tools/testing/selftests/bpf/Makefile [ctx conflicts] Signed-off-by: Pu Lehui <pulehui(a)huawei.com> --- tools/testing/selftests/bpf/Makefile | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index 8ce50befca91..e97ec89fe83d 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -208,15 +208,17 @@ endif # do not fail. Static builds leave urandom_read relying on system-wide shared libraries. $(OUTPUT)/liburandom_read.so: urandom_read_lib1.c urandom_read_lib2.c $(call msg,LIB,,$@) - $(Q)$(CLANG) $(filter-out -static,$(CFLAGS) $(LDFLAGS)) \ + $(Q)$(CLANG) $(CLANG_TARGET_ARCH) \ + $(filter-out -static,$(CFLAGS) $(LDFLAGS)) \ $^ $(filter-out -static,$(LDLIBS)) \ -fuse-ld=$(LLD) -Wl,-znoseparate-code -Wl,--build-id=sha1 \ -fPIC -shared -o $@ $(OUTPUT)/urandom_read: urandom_read.c urandom_read_aux.c $(OUTPUT)/liburandom_read.so $(call msg,BINARY,,$@) - $(Q)$(CLANG) $(filter-out -static,$(CFLAGS) $(LDFLAGS)) $(filter %.c,$^) \ - -lurandom_read $(filter-out -static,$(LDLIBS)) -L$(OUTPUT) \ + $(Q)$(CLANG) $(CLANG_TARGET_ARCH) \ + $(filter-out -static,$(CFLAGS) $(LDFLAGS)) $(filter %.c,$^) \ + -lurandom_read $(filter-out -static,$(LDLIBS)) -L$(OUTPUT) \ -fuse-ld=$(LLD) -Wl,-znoseparate-code -Wl,--build-id=sha1 \ -Wl,-rpath=. -o $@ -- 2.34.1

2 1

[PATCH OLK-6.6] arm64/mpam: Fix warning of schedule state in resctrl_arch_mon_ctx_alloc()
by Zeng Heng 12 Mar '26

12 Mar '26

Offering: HULK hulk inclusion category: bugfix bugzilla: https://atomgit.com/openeuler/kernel/issues/8686 ------------------ resctrl_arch_mon_ctx_alloc() triggers a scheduling state warning when calling kmalloc() while the task is in a non-running state: do not call blocking ops when !TASK_RUNNING; state=1 set at prepare_to_wait WARNING: CPU: 78 PID: 12592 at kernel/sched/core.c:10584 _might_sleep Call trace: _might_sleep+0x1cc/0xf8 _kmalloc_cache_alloc_node+0x3a0/0x4e0 kmalloc_trace+0x44/0x120 resctrl_arch_mon_ctx_alloc+0xf0/0x178 mon_event_read+0xa0/0x308 mkdir_mondata_subdir+0x24c/0x330 mkdir_mondata_all+0x17c/0x248 rdt_get_tree+0x2e8/0x680 vfs_get_tree+0x5c/0x190 do_new_mount+0x27c/0x408 path_mount+0x2ac/0x448 arm64_sys_mount+0x1d4/0x228 Ensure the allocation is performed in TASK_RUNNING state to avoid schedule state corrupted. Fixes: 9119da143939 ("arm_mpam: resctrl: Allow resctrl to allocate monitors") Signed-off-by: Zeng Heng <zengheng4(a)huawei.com> --- drivers/platform/mpam/mpam_resctrl.c | 25 +++---------------------- 1 file changed, 3 insertions(+), 22 deletions(-) diff --git a/drivers/platform/mpam/mpam_resctrl.c b/drivers/platform/mpam/mpam_resctrl.c index 1a26a0ed2cff..b6681f328aaa 100644 --- a/drivers/platform/mpam/mpam_resctrl.c +++ b/drivers/platform/mpam/mpam_resctrl.c @@ -388,11 +388,11 @@ struct rdt_resource *resctrl_arch_get_resource(enum resctrl_res_level l) return &mpam_resctrl_exports[l].resctrl_res; } -static void *resctrl_arch_mon_ctx_alloc_no_wait(struct rdt_resource *r, - int evtid) +void *resctrl_arch_mon_ctx_alloc(struct rdt_resource *r, int evtid) { - u32 *ret = kmalloc(sizeof(*ret), GFP_KERNEL); + u32 *ret; + ret = kmalloc(sizeof(*ret), GFP_KERNEL); if (!ret) return ERR_PTR(-ENOMEM); @@ -400,25 +400,6 @@ static void *resctrl_arch_mon_ctx_alloc_no_wait(struct rdt_resource *r, return ret; } -void *resctrl_arch_mon_ctx_alloc(struct rdt_resource *r, int evtid) -{ - DEFINE_WAIT(wait); - void *ret; - - might_sleep(); - - do { - prepare_to_wait(&resctrl_mon_ctx_waiters, &wait, - TASK_INTERRUPTIBLE); - ret = resctrl_arch_mon_ctx_alloc_no_wait(r, evtid); - if (PTR_ERR(ret) == -ENOSPC) - schedule(); - } while (PTR_ERR(ret) == -ENOSPC && !signal_pending(current)); - finish_wait(&resctrl_mon_ctx_waiters, &wait); - - return ret; -} - void resctrl_arch_mon_ctx_free(struct rdt_resource *r, int evtid, void *arch_mon_ctx) { -- 2.25.1

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[PATCH OLK-6.6] Revert "drivers: core: synchronize really_probe() and dev_uevent()"
by Lin Ruifeng 12 Mar '26

12 Mar '26

From: Dmitry Torokhov <dmitry.torokhov(a)gmail.com> stable inclusion from stable-v6.6.89 commit d29c2d53357fd35f24b7acba594725a5be6404d7 category: bugfix bugzilla: https://atomgit.com/openeuler/kernel/issues/8715 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- commit dc1771f718548f7d4b93991b174c6e7b5e1ba410 upstream. This reverts commit c0a40097f0bc81deafc15f9195d1fb54595cd6d0. Probing a device can take arbitrary long time. In the field we observed that, for example, probing a bad micro-SD cards in an external USB card reader (or maybe cards were good but cables were flaky) sometimes takes longer than 2 minutes due to multiple retries at various levels of the stack. We can not block uevent_show() method for that long because udev is reading that attribute very often and that blocks udev and interferes with booting of the system. The change that introduced locking was concerned with dev_uevent() racing with unbinding the driver. However we can handle it without locking (which will be done in subsequent patch). There was also claim that synchronization with probe() is needed to properly load USB drivers, however this is a red herring: the change adding the lock was introduced in May of last year and USB loading and probing worked properly for many years before that. Revert the harmful locking. Cc: stable(a)vger.kernel.org Signed-off-by: Dmitry Torokhov <dmitry.torokhov(a)gmail.com> Reviewed-by: Masami Hiramatsu (Google) <mhiramat(a)kernel.org> Link: https://lore.kernel.org/r/20250311052417.1846985-1-dmitry.torokhov@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Lin Ruifeng <linruifeng4(a)huawei.com> --- drivers/base/core.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/drivers/base/core.c b/drivers/base/core.c index 9872ce765eaa..8a4c3bc7bafa 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -2707,11 +2707,8 @@ static ssize_t uevent_show(struct device *dev, struct device_attribute *attr, if (!env) return -ENOMEM; - /* Synchronize with really_probe() */ - device_lock(dev); /* let the kset specific function add its keys */ retval = kset->uevent_ops->uevent(&dev->kobj, env); - device_unlock(dev); if (retval) goto out; -- 2.43.0

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[PATCH OLK-6.6 0/3] Fix RT priority Setting
by Liu Kai 12 Mar '26

12 Mar '26

Fix RT priority Setting Liu Kai (3): xsched: refactor xse_this_grp_xcu to xse_this_cfs_rq for clarity and correctness xsched: fix typo in xcu cgroup subsys released callback name xsched: initialize tgid before configuring RT priority include/linux/xsched.h | 29 ++++++++++++++--------------- kernel/xsched/cfs.c | 2 +- kernel/xsched/cgroup.c | 4 ++-- kernel/xsched/core.c | 3 +-- 4 files changed, 18 insertions(+), 20 deletions(-) -- 2.34.1

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[PATCH OLK-6.6 0/3] optimize lightweight load balancing
by Chen Jinghuang 12 Mar '26

12 Mar '26

*** BLURB HERE *** Chen Jinghuang (2): sched: Fix kabi breakage of struct sched_domain for newidle_stats sched: expand sysctl_sched_features to unsigned long Peter Zijlstra (Intel) (1): sched/fair: Proportional newidle balance include/linux/sched/topology.h | 5 ++++ kernel/sched/core.c | 5 +++- kernel/sched/fair.c | 50 +++++++++++++++++++++++++++++++--- kernel/sched/features.h | 5 ++++ kernel/sched/sched.h | 9 +++++- kernel/sched/topology.c | 6 ++++ 6 files changed, 74 insertions(+), 6 deletions(-) -- 2.34.1

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[PATCH OLK-5.10] scsi: hisi_sas: Change the debugfs parameters dump count default value
by Yihang Li 12 Mar '26

12 Mar '26

driver inclusion category: feature bugzilla: https://atomgit.com/openeuler/kernel/issues/8713 ----------------------------------------------------------------------------- The memory allocation time of the DFX is changed from device initialization to dump occurs, so restore the default setting hisi_sas_debugfs_dump_count to 50. Signed-off-by: Yihang Li <liyihang9(a)h-partners.com> --- drivers/scsi/hisi_sas/hisi_sas_main.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/hisi_sas/hisi_sas_main.c b/drivers/scsi/hisi_sas/hisi_sas_main.c index a525d484d6e2..c58b77902782 100644 --- a/drivers/scsi/hisi_sas/hisi_sas_main.c +++ b/drivers/scsi/hisi_sas/hisi_sas_main.c @@ -2955,12 +2955,12 @@ EXPORT_SYMBOL_GPL(hisi_sas_remove); #if IS_ENABLED(CONFIG_SCSI_HISI_SAS_DEBUGFS_DEFAULT_ENABLE) #define DEBUGFS_ENABLE_DEFAULT "enabled" bool hisi_sas_debugfs_enable = true; +u32 hisi_sas_debugfs_dump_count = 50; #else #define DEBUGFS_ENABLE_DEFAULT "disabled" bool hisi_sas_debugfs_enable; -#endif - u32 hisi_sas_debugfs_dump_count = 1; +#endif EXPORT_SYMBOL_GPL(hisi_sas_debugfs_enable); module_param_named(debugfs_enable, hisi_sas_debugfs_enable, bool, 0444); -- 2.33.0

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