Patch "sched/core: Remove false-positive warning from wake_up_process()" has been added to the 3.14-stable tree

Patch "sched/core: Remove false-positive warning from wake_up_process()" has been added to the 3.14-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

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

to the 3.14-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     sched-core-remove-false-positive-warning-from-wake_up_process.patch
and it can be found in the queue-3.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 119d6f6a3be8b424b200dcee56e74484d5445f7e Mon Sep 17 00:00:00 2001
From: Sasha Levin <sasha.levin@oracle.com>
Date: Mon, 30 Nov 2015 20:34:20 -0500
Subject: sched/core: Remove false-positive warning from wake_up_process()

From: Sasha Levin <sasha.levin@oracle.com>

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>

---
 kernel/sched/core.c |    1 -
 1 file changed, 1 deletion(-)

--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -1696,7 +1696,6 @@ 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);


Patches currently in stable-queue which might be from sasha.levin@oracle.com are

queue-3.14/sched-core-remove-false-positive-warning-from-wake_up_process.patch
queue-3.14/rds-verify-the-underlying-transport-exists-before-creating-a-connection.patch
queue-3.14/rds-fix-race-condition-when-sending-a-message-on-unbound-socket.patch