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

Upstream commit 9067ac85d533651b98c2ff903182a20cbb361fcb.

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>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/kernel/sched.c b/kernel/sched.c
index aacd55f..cd2b7cb 100644 (file)
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -2778,7 +2778,8 @@ 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);