1 files changed, 5 insertions, 3 deletions

diff --git a/block/elevator.c b/block/elevator.c
index 6df2b5056b51..923a9139106c 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -242,9 +242,11 @@ int elevator_init(struct request_queue *q, char *name)
 {
         struct elevator_type *e = NULL;
         struct elevator_queue *eq;
-        int ret = 0;
         void *data;
 
+        if (unlikely(q->elevator))
+                return 0;
+
         INIT_LIST_HEAD(&q->queue_head);
         q->last_merge = NULL;
         q->end_sector = 0;
@@ -284,7 +286,7 @@ int elevator_init(struct request_queue *q, char *name)
         }
 
         elevator_attach(q, eq, data);
-        return ret;
+        return 0;
 }
 EXPORT_SYMBOL(elevator_init);
 
@@ -1097,7 +1099,7 @@ ssize_t elv_iosched_show(struct request_queue *q, char *name)
         struct elevator_type *__e;
         int len = 0;
 
-        if (!q->elevator)
+        if (!q->elevator || !blk_queue_stackable(q))
                 return sprintf(name, "none\n");
 
         elv = e->elevator_type;