From f660daac474c6f7c2d710100e29b3276a6f4db0a Mon Sep 17 00:00:00 2001
From: David Rientjes <rientjes@google.com>
Date: Mon, 31 Oct 2011 17:07:07 -0700
Subject: [PATCH] oom: thaw threads if oom killed thread is frozen before
 deferring

If a thread has been oom killed and is frozen, thaw it before returning to
the page allocator.  Otherwise, it can stay frozen indefinitely and no
memory will be freed.

Signed-off-by: David Rientjes <rientjes@google.com>
Reported-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Acked-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 mm/oom_kill.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index 626303b52f3c..d897262068e2 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -32,6 +32,7 @@
 #include <linux/mempolicy.h>
 #include <linux/security.h>
 #include <linux/ptrace.h>
+#include <linux/freezer.h>
 
 int sysctl_panic_on_oom;
 int sysctl_oom_kill_allocating_task;
@@ -317,8 +318,11 @@ static struct task_struct *select_bad_process(unsigned int *ppoints,
 		 * blocked waiting for another task which itself is waiting
 		 * for memory. Is there a better alternative?
 		 */
-		if (test_tsk_thread_flag(p, TIF_MEMDIE))
+		if (test_tsk_thread_flag(p, TIF_MEMDIE)) {
+			if (unlikely(frozen(p)))
+				thaw_process(p);
 			return ERR_PTR(-1UL);
+		}
 		if (!p->mm)
 			continue;
 
-- 
2.20.1