diff --git a/fs/lockd/svclock.c b/fs/lockd/svclock.c
index 82db7b323b83..fe9bdb4a220c 100644
--- a/fs/lockd/svclock.c
+++ b/fs/lockd/svclock.c
@@ -795,6 +795,17 @@ static void nlmsvc_grant_callback(struct rpc_task *task, void *data)
 
 	dprintk("lockd: GRANT_MSG RPC callback\n");
 
+	/* if the block is not on a list at this point then it has
+	 * been invalidated. Don't try to requeue it.
+	 *
+	 * FIXME: it's possible that the block is removed from the list
+	 * after this check but before the nlmsvc_insert_block. In that
+	 * case it will be added back. Perhaps we need better locking
+	 * for nlm_blocked?
+	 */
+	if (list_empty(&block->b_list))
+		return;
+
 	/* Technically, we should down the file semaphore here. Since we
 	 * move the block towards the head of the queue only, no harm
 	 * can be done, though. */