diff --git a/[refs] b/[refs]
index 98b7413fc3f3..462e3b9f8f45 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: a67adb997419fb53540d4a4f79c6471c60bc69b6
+refs/heads/master: 103a197c0c4ec936f5a243b5b092e4e49213f569
diff --git a/trunk/security/device_cgroup.c b/trunk/security/device_cgroup.c
index 19ecc8de9e6b..d794abcc4b3b 100644
--- a/trunk/security/device_cgroup.c
+++ b/trunk/security/device_cgroup.c
@@ -215,7 +215,9 @@ static void devcgroup_css_free(struct cgroup *cgroup)
 	struct dev_cgroup *dev_cgroup;
 
 	dev_cgroup = cgroup_to_devcgroup(cgroup);
+	mutex_lock(&devcgroup_mutex);
 	dev_exception_clean(dev_cgroup);
+	mutex_unlock(&devcgroup_mutex);
 	kfree(dev_cgroup);
 }