diff --git a/[refs] b/[refs]
index 21bc12bb5300..dc1bbbd56341 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 7109c4429af3640f79a638f177fc5d05b9807149
+refs/heads/master: b77d69db9f4ba03b2ed17e383c2d73ca89f5ab14
diff --git a/trunk/kernel/sched_fair.c b/trunk/kernel/sched_fair.c
index 9f06094e5275..0c718857176f 100644
--- a/trunk/kernel/sched_fair.c
+++ b/trunk/kernel/sched_fair.c
@@ -489,6 +489,9 @@ update_stats_wait_end(struct cfs_rq *cfs_rq, struct sched_entity *se)
 {
 	unsigned long delta_fair;
 
+	if (unlikely(!se->wait_start_fair))
+		return;
+
 	delta_fair = (unsigned long)min((u64)(2*sysctl_sched_runtime_limit),
 			(u64)(cfs_rq->fair_clock - se->wait_start_fair));