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

oleg-nesterov · torvalds · commit 9067ac85d533 · 2013-01-22T10:08:17.000-08:00
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 &lt;oleg@redhat.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
@@ -1523,7 +1523,8 @@ static void try_to_wake_up_local(struct task_struct *p)
  */
 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);
 

Original file line number	Diff line number	Diff line change
`@@ -1523,7 +1523,8 @@ static void try_to_wake_up_local(struct task_struct *p)`
`1523`	`1523`	`*/`
`1524`	`1524`	`int wake_up_process(struct task_struct *p)`
`1525`	`1525`	`{`
`1526`		`- return try_to_wake_up(p, TASK_ALL, 0);`
	`1526`	`+ WARN_ON(task_is_stopped_or_traced(p));`
	`1527`	`+ return try_to_wake_up(p, TASK_NORMAL, 0);`
`1527`	`1528`	`}`
`1528`	`1529`	`EXPORT_SYMBOL(wake_up_process);`
`1529`	`1530`