From: Sasha Levin <sasha.levin@oracle.com>
Date: Tue, 1 Dec 2015 01:34:20 +0000 (-0500)
Subject: sched/core: Remove false-positive warning from wake_up_process()
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=6bf97b05008739ad7d644758301a427460479537;p=GitHub%2Fmt8127%2Fandroid_kernel_alcatel_ttab.git

sched/core: Remove false-positive warning from wake_up_process()

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@oracle.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: oleg@redhat.com
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@oracle.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index c771f2547bef..f234c84d36c8 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -1587,7 +1587,6 @@ 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);