perf: Fix free_event()
With the context rework stuff we can actually end up freeing an event
before it gets attached to a context.
Reported-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index bc46bff6..440f9ca 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -2150,7 +2150,9 @@
if (event->destroy)
event->destroy(event);
- put_ctx(event->ctx);
+ if (event->ctx)
+ put_ctx(event->ctx);
+
call_rcu(&event->rcu_head, free_event_rcu);
}