Commit 650226bd authored Jun 06, 2014 by Oleg Nesterov Committed by Linus Torvalds Jun 06, 2014

ptrace: task_clear_jobctl_trapping()->wake_up_bit() needs mb()



__wake_up_bit() checks waitqueue_active() and thus the caller needs mb()
as wake_up_bit() documents, fix task_clear_jobctl_trapping().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 4e52365f

kernel/signal.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -277,6 +277,7 @@ void task_clear_jobctl_trapping(struct task_struct *task)
		{
		if (unlikely(task->jobctl & JOBCTL_TRAPPING)) {
		task->jobctl &= ~JOBCTL_TRAPPING;
		smp_mb(); /* advised by wake_up_bit() */
		wake_up_bit(&task->jobctl, JOBCTL_TRAPPING_BIT);
		}
		}