[PATCH 3.16.y-ckt 123/126] sched/core: Remove false-positive warning from wake_up_process()

From: Luis Henriques
Date: Wed Jan 06 2016 - 05:42:18 EST


3.16.7-ckt22 -stable review patch. If anyone has any objections, please let me know.

------------------

From: Sasha Levin <sasha.levin@xxxxxxxxxx>

commit 119d6f6a3be8b424b200dcee56e74484d5445f7e upstream.

Because wakeups can (fundamentally) be late, a task might not be in
the expected state. Therefore testing against a task's state is racy,
and can yield false positives.

Signed-off-by: Sasha Levin <sasha.levin@xxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Acked-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Mike Galbraith <efault@xxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: oleg@xxxxxxxxxx
Fixes: 9067ac85d533 ("wake_up_process() should be never used to wakeup a TASK_STOPPED/TRACED task")
Link: http://lkml.kernel.org/r/1448933660-23082-1-git-send-email-sasha.levin@xxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Signed-off-by: Luis Henriques <luis.henriques@xxxxxxxxxxxxx>
---
kernel/sched/core.c | 1 -
1 file changed, 1 deletion(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 0417f4b1a5f3..c49c16c405b7 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -1772,7 +1772,6 @@ out:
*/
int wake_up_process(struct task_struct *p)
{
- WARN_ON(task_is_stopped_or_traced(p));
return try_to_wake_up(p, TASK_NORMAL, 0);
}
EXPORT_SYMBOL(wake_up_process);
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/