From: Oleg Nesterov <oleg@redhat.com>
Date: Mon, 21 Jan 2013 19:48:17 +0000 (+0100)
Subject: wake_up_process() should be never used to wakeup a TASK_STOPPED/TRACED task
X-Git-Tag: v3.2.39~30
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=8957028bd89221048c784d524ee42513356fc822;p=thirdparty%2Fkernel%2Fstable.git

wake_up_process() should be never used to wakeup a TASK_STOPPED/TRACED task

commit 9067ac85d533651b98c2ff903182a20cbb361fcb upstream.

wake_up_process() should never wakeup a TASK_STOPPED/TRACED task.
Change it to use TASK_NORMAL and add the WARN_ON().

TASK_ALL has no other users, probably can be killed.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bwh: Backported to 3.2: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---

diff --git a/kernel/sched.c b/kernel/sched.c
index fcc893f6fbaa2..eeeec4e6fa042 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -2924,7 +2924,8 @@ out:
  */
 int wake_up_process(struct task_struct *p)
 {
-	return try_to_wake_up(p, TASK_ALL, 0);
+	WARN_ON(task_is_stopped_or_traced(p));
+	return try_to_wake_up(p, TASK_NORMAL, 0);
 }
 EXPORT_SYMBOL(wake_up_process);