A race condition exists between perf_event_exit_task() and perf_pending_task().

During begin_new_exec(), perf_event_exit_task() may be called, and the
PF_EXITING flag is not set on task. so perf_sigtrap() continues to execute
and triggers WARN_ON_ONCE(event->ctx->task != current).

To fix this problem, also check if the event->ctx->task is TASK_TOMBSTONE.

Fixes: 97ba62b27867 ("perf: Add support for SIGTRAP on perf events")
Signed-off-by: Luo Gengkun <luogengkun2@huawei.com>
---
 kernel/events/core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 1f5699b339ec..3422900263fa 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -7543,7 +7543,7 @@ static void perf_sigtrap(struct perf_event *event)
 	 * Both perf_pending_task() and perf_pending_irq() can race with the
 	 * task exiting.
 	 */
-	if (current->flags & PF_EXITING)
+	if (current->flags & PF_EXITING || event->ctx->task == TASK_TOMBSTONE)
 		return;
 
 	/*
-- 
2.34.1