From: Greg Kroah-Hartman Date: Tue, 10 Sep 2024 07:36:32 +0000 (+0200) Subject: 4.19-stable patches X-Git-Tag: v4.19.322~32 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=943cdd3508be0b4954b32ed2c1805dd192b06baf;p=thirdparty%2Fkernel%2Fstable-queue.git 4.19-stable patches added patches: rtmutex-drop-rt_mutex-wait_lock-before-scheduling.patch --- diff --git a/queue-4.19/rtmutex-drop-rt_mutex-wait_lock-before-scheduling.patch b/queue-4.19/rtmutex-drop-rt_mutex-wait_lock-before-scheduling.patch new file mode 100644 index 00000000000..fc063c42bfd --- /dev/null +++ b/queue-4.19/rtmutex-drop-rt_mutex-wait_lock-before-scheduling.patch @@ -0,0 +1,57 @@ +From d33d26036a0274b472299d7dcdaa5fb34329f91b Mon Sep 17 00:00:00 2001 +From: Roland Xu +Date: Thu, 15 Aug 2024 10:58:13 +0800 +Subject: rtmutex: Drop rt_mutex::wait_lock before scheduling + +From: Roland Xu + +commit d33d26036a0274b472299d7dcdaa5fb34329f91b upstream. + +rt_mutex_handle_deadlock() is called with rt_mutex::wait_lock held. In the +good case it returns with the lock held and in the deadlock case it emits a +warning and goes into an endless scheduling loop with the lock held, which +triggers the 'scheduling in atomic' warning. + +Unlock rt_mutex::wait_lock in the dead lock case before issuing the warning +and dropping into the schedule for ever loop. + +[ tglx: Moved unlock before the WARN(), removed the pointless comment, + massaged changelog, added Fixes tag ] + +Fixes: 3d5c9340d194 ("rtmutex: Handle deadlock detection smarter") +Signed-off-by: Roland Xu +Signed-off-by: Thomas Gleixner +Cc: stable@vger.kernel.org +Link: https://lore.kernel.org/all/ME0P300MB063599BEF0743B8FA339C2CECC802@ME0P300MB0635.AUSP300.PROD.OUTLOOK.COM +Signed-off-by: Greg Kroah-Hartman +--- + kernel/locking/rtmutex.c | 4 +++- + 1 file changed, 3 insertions(+), 1 deletion(-) + +--- a/kernel/locking/rtmutex.c ++++ b/kernel/locking/rtmutex.c +@@ -1205,6 +1205,7 @@ __rt_mutex_slowlock(struct rt_mutex *loc + } + + static void rt_mutex_handle_deadlock(int res, int detect_deadlock, ++ struct rt_mutex *lock, + struct rt_mutex_waiter *w) + { + /* +@@ -1214,6 +1215,7 @@ static void rt_mutex_handle_deadlock(int + if (res != -EDEADLOCK || detect_deadlock) + return; + ++ raw_spin_unlock_irq(&lock->wait_lock); + /* + * Yell lowdly and stop the task right here. + */ +@@ -1269,7 +1271,7 @@ rt_mutex_slowlock(struct rt_mutex *lock, + if (unlikely(ret)) { + __set_current_state(TASK_RUNNING); + remove_waiter(lock, &waiter); +- rt_mutex_handle_deadlock(ret, chwalk, &waiter); ++ rt_mutex_handle_deadlock(ret, chwalk, lock, &waiter); + } + + /* diff --git a/queue-4.19/series b/queue-4.19/series index 85ac27934fb..80847d69466 100644 --- a/queue-4.19/series +++ b/queue-4.19/series @@ -89,3 +89,4 @@ acpi-processor-return-an-error-if-acpi_processor_get.patch acpi-processor-fix-memory-leaks-in-error-paths-of-pr.patch drm-i915-fence-mark-debug_fence_init_onstack-with-__.patch drm-i915-fence-mark-debug_fence_free-with-__maybe_un.patch +rtmutex-drop-rt_mutex-wait_lock-before-scheduling.patch