diff --git a/ipc/shm.c b/ipc/shm.c
index e77ec698..0add3fa 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -737,6 +737,10 @@
 	case SHM_LOCK:
 	case SHM_UNLOCK:
 	{
+		struct file *uninitialized_var(shm_file);
+
+		lru_add_drain_all();  /* drain pagevecs to lru lists */
+
 		shp = shm_lock_check(ns, shmid);
 		if (IS_ERR(shp)) {
 			err = PTR_ERR(shp);