From f5c7f1fc8f28f21deaf1391973162804cce24032 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Fri, 16 Aug 2024 09:34:15 +0000 Subject: [PATCH 1/4] ASoC: tracing: Export SND_SOC_DAPM_DIR_OUT to its value stable inclusion from stable-v4.19.316 commit 60c68092723ea420215e9c3d5530038bc6568739 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/IAJIPJ Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=60c68092723e -------------------------------- [ Upstream commit 58300f8d6a48e58d1843199be743f819e2791ea3 ] The string SND_SOC_DAPM_DIR_OUT is printed in the snd_soc_dapm_path trace event instead of its value: (((REC->path_dir) == SND_SOC_DAPM_DIR_OUT) ? "->" : "<-") User space cannot parse this, as it has no idea what SND_SOC_DAPM_DIR_OUT is. Use TRACE_DEFINE_ENUM() to convert it to its value: (((REC->path_dir) == 1) ? "->" : "<-") So that user space tools, such as perf and trace-cmd, can parse it correctly. Reported-by: Luca Ceresoli Fixes: 6e588a0d839b5 ("ASoC: dapm: Consolidate path trace events") Signed-off-by: Steven Rostedt (Google) Link: https://lore.kernel.org/r/20240416000303.04670cdf@rorschach.local.home Signed-off-by: Mark Brown Signed-off-by: Sasha Levin Signed-off-by: Xiaomeng Zhang --- include/trace/events/asoc.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/include/trace/events/asoc.h b/include/trace/events/asoc.h index 40c300fe704d..f62d5b702426 100644 --- a/include/trace/events/asoc.h +++ b/include/trace/events/asoc.h @@ -11,6 +11,8 @@ #define DAPM_DIRECT "(direct)" #define DAPM_ARROW(dir) (((dir) == SND_SOC_DAPM_DIR_OUT) ? "->" : "<-") +TRACE_DEFINE_ENUM(SND_SOC_DAPM_DIR_OUT); + struct snd_soc_jack; struct snd_soc_card; struct snd_soc_dapm_widget; -- Gitee From b0f6a5db93150b8bb6bfb07bab69f8bf95efcee8 Mon Sep 17 00:00:00 2001 From: Rik van Riel Date: Fri, 16 Aug 2024 09:34:16 +0000 Subject: [PATCH 2/4] fs/proc: fix softlockup in __read_vmcore stable inclusion from stable-v4.19.317 commit 7bdf1d550ddfcd9ab797087421f77b7aceddc8a7 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAJKLA Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7bdf1d550ddf -------------------------------- commit 5cbcb62dddf5346077feb82b7b0c9254222d3445 upstream. While taking a kernel core dump with makedumpfile on a larger system, softlockup messages often appear. While softlockup warnings can be harmless, they can also interfere with things like RCU freeing memory, which can be problematic when the kdump kexec image is configured with as little memory as possible. Avoid the softlockup, and give things like work items and RCU a chance to do their thing during __read_vmcore by adding a cond_resched. Link: https://lkml.kernel.org/r/20240507091858.36ff767f@imladris.surriel.com Signed-off-by: Rik van Riel Acked-by: Baoquan He Cc: Dave Young Cc: Vivek Goyal Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman Signed-off-by: Xiaomeng Zhang --- fs/proc/vmcore.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/proc/vmcore.c b/fs/proc/vmcore.c index f5dfedc01552..cd384a1ebef5 100644 --- a/fs/proc/vmcore.c +++ b/fs/proc/vmcore.c @@ -359,6 +359,8 @@ static ssize_t __read_vmcore(char *buffer, size_t buflen, loff_t *fpos, /* leave now if filled buffer already */ if (buflen == 0) return acc; + + cond_resched(); } list_for_each_entry(m, &vmcore_list, list) { -- Gitee From 351bb8f882e99954cc054b9ccedbfcf972361f4b Mon Sep 17 00:00:00 2001 From: Jeff Johnson Date: Fri, 16 Aug 2024 09:34:17 +0000 Subject: [PATCH 3/4] tracing: Add MODULE_DESCRIPTION() to preemptirq_delay_test stable inclusion from stable-v4.19.317 commit 876d7d009c528caea5af95a70ab998374cbc7c7f category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAJLBC Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=876d7d009c52 -------------------------------- [ Upstream commit 23748e3e0fbfe471eff5ce439921629f6a427828 ] Fix the 'make W=1' warning: WARNING: modpost: missing MODULE_DESCRIPTION() in kernel/trace/preemptirq_delay_test.o Link: https://lore.kernel.org/linux-trace-kernel/20240518-md-preemptirq_delay_test-v1-1-387d11b30d85@quicinc.com Cc: stable@vger.kernel.org Cc: Mathieu Desnoyers Fixes: f96e8577da10 ("lib: Add module for testing preemptoff/irqsoff latency tracers") Acked-by: Masami Hiramatsu (Google) Signed-off-by: Jeff Johnson Signed-off-by: Steven Rostedt (Google) Signed-off-by: Sasha Levin Signed-off-by: Xiaomeng Zhang --- kernel/trace/preemptirq_delay_test.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/trace/preemptirq_delay_test.c b/kernel/trace/preemptirq_delay_test.c index d8765c952fab..4692c87d4b69 100644 --- a/kernel/trace/preemptirq_delay_test.c +++ b/kernel/trace/preemptirq_delay_test.c @@ -69,4 +69,5 @@ static void __exit preemptirq_delay_exit(void) module_init(preemptirq_delay_init) module_exit(preemptirq_delay_exit) +MODULE_DESCRIPTION("Preempt / IRQ disable delay thread to test latency tracers"); MODULE_LICENSE("GPL v2"); -- Gitee From c634a9b1370a59d214ccbfcffa1d73d569616aab Mon Sep 17 00:00:00 2001 From: Haifeng Xu Date: Fri, 16 Aug 2024 09:34:18 +0000 Subject: [PATCH 4/4] perf/core: Fix missing wakeup when waiting for context reference stable inclusion from stable-v4.19.317 commit c23ead9986a17c793d39be11ce6c084904c9c44a category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAJLGS Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c23ead9986a1 -------------------------------- [ Upstream commit 74751ef5c1912ebd3e65c3b65f45587e05ce5d36 ] In our production environment, we found many hung tasks which are blocked for more than 18 hours. Their call traces are like this: [346278.191038] __schedule+0x2d8/0x890 [346278.191046] schedule+0x4e/0xb0 [346278.191049] perf_event_free_task+0x220/0x270 [346278.191056] ? init_wait_var_entry+0x50/0x50 [346278.191060] copy_process+0x663/0x18d0 [346278.191068] kernel_clone+0x9d/0x3d0 [346278.191072] __do_sys_clone+0x5d/0x80 [346278.191076] __x64_sys_clone+0x25/0x30 [346278.191079] do_syscall_64+0x5c/0xc0 [346278.191083] ? syscall_exit_to_user_mode+0x27/0x50 [346278.191086] ? do_syscall_64+0x69/0xc0 [346278.191088] ? irqentry_exit_to_user_mode+0x9/0x20 [346278.191092] ? irqentry_exit+0x19/0x30 [346278.191095] ? exc_page_fault+0x89/0x160 [346278.191097] ? asm_exc_page_fault+0x8/0x30 [346278.191102] entry_SYSCALL_64_after_hwframe+0x44/0xae The task was waiting for the refcount become to 1, but from the vmcore, we found the refcount has already been 1. It seems that the task didn't get woken up by perf_event_release_kernel() and got stuck forever. The below scenario may cause the problem. Thread A Thread B ... ... perf_event_free_task perf_event_release_kernel ... acquire event->child_mutex ... get_ctx ... release event->child_mutex acquire ctx->mutex ... perf_free_event (acquire/release event->child_mutex) ... release ctx->mutex wait_var_event acquire ctx->mutex acquire event->child_mutex # move existing events to free_list release event->child_mutex release ctx->mutex put_ctx ... ... In this case, all events of the ctx have been freed, so we couldn't find the ctx in free_list and Thread A will miss the wakeup. It's thus necessary to add a wakeup after dropping the reference. Fixes: 1cf8dfe8a661 ("perf/core: Fix race between close() and fork()") Signed-off-by: Haifeng Xu Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Frederic Weisbecker Acked-by: Mark Rutland Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20240513103948.33570-1-haifeng.xu@shopee.com Signed-off-by: Sasha Levin Signed-off-by: Xiaomeng Zhang --- kernel/events/core.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/kernel/events/core.c b/kernel/events/core.c index be528436a03b..9070eabd890e 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -4664,6 +4664,7 @@ int perf_event_release_kernel(struct perf_event *event) again: mutex_lock(&event->child_mutex); list_for_each_entry(child, &event->child_list, child_list) { + void *var = NULL; /* * Cannot change, child events are not migrated, see the @@ -4704,11 +4705,23 @@ int perf_event_release_kernel(struct perf_event *event) * this can't be the last reference. */ put_event(event); + } else { + var = &ctx->refcount; } mutex_unlock(&event->child_mutex); mutex_unlock(&ctx->mutex); put_ctx(ctx); + + if (var) { + /* + * If perf_event_free_task() has deleted all events from the + * ctx while the child_mutex got released above, make sure to + * notify about the preceding put_ctx(). + */ + smp_mb(); /* pairs with wait_var_event() */ + wake_up_var(var); + } goto again; } mutex_unlock(&event->child_mutex); -- Gitee