[PATCH 2/2] signal: sys_pause() should check signal_pending()

[Oleg Nesterov <oleg@redhat.com>]

ERESTART* is always wrong without TIF_SIGPENDING. Teach sys_pause()
to handle the spurious wakeup correctly.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
---

 kernel/signal.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

--- sigprocmask/kernel/signal.c~pause_ck_signal_pending	2011-05-23 18:09:49.000000000 +0200
+++ sigprocmask/kernel/signal.c	2011-05-23 18:52:24.000000000 +0200
@@ -3023,8 +3023,10 @@ SYSCALL_DEFINE2(signal, int, sig, __sigh
 
 SYSCALL_DEFINE0(pause)
 {
-	current->state = TASK_INTERRUPTIBLE;
-	schedule();
+	while (!signal_pending(current)) {
+		current->state = TASK_INTERRUPTIBLE;
+		schedule();
+	}
 	return -ERESTARTNOHAND;
 }