[PATCH OLK-6.6 0/2] Merge March mainline patch
Breno Leitao (1): perf/core: Add RCU read lock protection to perf_iterate_ctx() Peter Zijlstra (1): perf/core: Fix pmus_lock vs. pmus_srcu ordering kernel/events/core.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) -- 2.34.1
反馈: 您发送到kernel@openeuler.org的补丁/补丁集，转换为PR失败！ 邮件列表地址：https://mailweb.openeuler.org/archives/list/kernel@openeuler.org/message/EVK... 失败原因：应用补丁/补丁集失败，Patch failed at 0002 perf/core: Add RCU read lock protection to perf_iterate_ctx() 建议解决方法：请查看失败原因， 确认补丁是否可以应用在当前期望分支的最新代码上 FeedBack: The patch(es) which you have sent to kernel@openeuler.org has been converted to PR failed! Mailing list address: https://mailweb.openeuler.org/archives/list/kernel@openeuler.org/message/EVK... Failed Reason: apply patch(es) failed, Patch failed at 0002 perf/core: Add RCU read lock protection to perf_iterate_ctx() Suggest Solution: please checkout if the failed patch(es) can work on the newest codes in expected branch
From: Peter Zijlstra <peterz@infradead.org> stable inclusion from stable-v6.6.83 commit 7c823e4c30d6fdc16089e13924260086eaea76be category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IBXQNU Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 2565e42539b120b81a68a58da961ce5d1e34eac8 ] Commit a63fbed776c7 ("perf/tracing/cpuhotplug: Fix locking order") placed pmus_lock inside pmus_srcu, this makes perf_pmu_unregister() trip lockdep. Move the locking about such that only pmu_idr and pmus (list) are modified while holding pmus_lock. This avoids doing synchronize_srcu() while holding pmus_lock and all is well again. Fixes: a63fbed776c7 ("perf/tracing/cpuhotplug: Fix locking order") Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20241104135517.679556858@infradead.org Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Luo Gengkun <luogengkun2@huawei.com> --- kernel/events/core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index c2b93f521497..d97575f18677 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -11669,6 +11669,8 @@ void perf_pmu_unregister(struct pmu *pmu) { mutex_lock(&pmus_lock); list_del_rcu(&pmu->entry); + idr_remove(&pmu_idr, pmu->type); + mutex_unlock(&pmus_lock); /* * We dereference the pmu list under both SRCU and regular RCU, so @@ -11678,7 +11680,6 @@ void perf_pmu_unregister(struct pmu *pmu) synchronize_rcu(); free_percpu(pmu->pmu_disable_count); - idr_remove(&pmu_idr, pmu->type); if (pmu_bus_running && pmu->dev && pmu->dev != PMU_NULL_DEV) { if (pmu->nr_addr_filters) device_remove_file(pmu->dev, &dev_attr_nr_addr_filters); @@ -11686,7 +11687,6 @@ void perf_pmu_unregister(struct pmu *pmu) put_device(pmu->dev); } free_pmu_context(pmu); - mutex_unlock(&pmus_lock); } EXPORT_SYMBOL_GPL(perf_pmu_unregister); -- 2.34.1
From: Breno Leitao <leitao@debian.org> stable inclusion from stable-v6.6.81 commit f390c2eea571945f357a2d3b9fcb1c015767132e category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IBXQNU Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit 0fe8813baf4b2e865d3b2c735ce1a15b86002c74 upstream. The perf_iterate_ctx() function performs RCU list traversal but currently lacks RCU read lock protection. This causes lockdep warnings when running perf probe with unshare(1) under CONFIG_PROVE_RCU_LIST=y: WARNING: suspicious RCU usage kernel/events/core.c:8168 RCU-list traversed in non-reader section!! Call Trace: lockdep_rcu_suspicious ? perf_event_addr_filters_apply perf_iterate_ctx perf_event_exec begin_new_exec ? load_elf_phdrs load_elf_binary ? lock_acquire ? find_held_lock ? bprm_execve bprm_execve do_execveat_common.isra.0 __x64_sys_execve do_syscall_64 entry_SYSCALL_64_after_hwframe This protection was previously present but was removed in commit bd2756811766 ("perf: Rewrite core context handling"). Add back the necessary rcu_read_lock()/rcu_read_unlock() pair around perf_iterate_ctx() call in perf_event_exec(). [ mingo: Use scoped_guard() as suggested by Peter ] Fixes: bd2756811766 ("perf: Rewrite core context handling") Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20250117-fix_perf_rcu-v1-1-13cb9210fc6a@debian.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Luo Gengkun <luogengkun2@huawei.com> --- kernel/events/core.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index d97575f18677..9b5d35c4a3ec 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -8124,7 +8124,8 @@ void perf_event_exec(void) perf_event_enable_on_exec(ctx); perf_event_remove_on_exec(ctx); - perf_iterate_ctx(ctx, perf_event_addr_filters_exec, NULL, true); + scoped_guard(rcu) + perf_iterate_ctx(ctx, perf_event_addr_filters_exec, NULL, true); perf_unpin_context(ctx); put_ctx(ctx); -- 2.34.1
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