kthread: fix return value of kthread_create() upon SIGKILL.

Commit 786235eeba0e ("kthread: make kthread_create() killable") meant
for allowing kthread_create() to abort as soon as killed by the
OOM-killer.  But returning -ENOMEM is wrong if killed by SIGKILL from
userspace.  Change kthread_create() to return -EINTR upon SIGKILL.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Oleg Nesterov <oleg@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: <stable@vger.kernel.org> [3.13+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/kernel/kthread.c b/kernel/kthread.c
index 9a130ec06f7a5aa38c92f2f7961db6131f43153d..c2390f41307bca58cdd9b14bb9530d8a16c20e6c 100644 (file)
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -262,7 +262,7 @@ static void create_kthread(struct kthread_create_info *create)
  * kthread_stop() has been called).  The return value should be zero
  * or a negative error number; it will be passed to kthread_stop().
  *
- * Returns a task_struct or ERR_PTR(-ENOMEM).
+ * Returns a task_struct or ERR_PTR(-ENOMEM) or ERR_PTR(-EINTR).
  */
 struct task_struct *kthread_create_on_node(int (*threadfn)(void *data),
                                           void *data, int node,
@@ -298,7 +298,7 @@ struct task_struct *kthread_create_on_node(int (*threadfn)(void *data),
                 * that thread.
                 */
                if (xchg(&create->done, NULL))
-                       return ERR_PTR(-ENOMEM);
+                       return ERR_PTR(-EINTR);
                /*
                 * kthreadd (or new kernel thread) will call complete()
                 * shortly.