diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index b9d321bdaa8a7eb91a0834c0398351f97fc36920..226103af30f05b0de9200a7020751dfe7917420d 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -1216,6 +1216,16 @@ static int nbd_start_device(struct nbd_device *nbd)
 		args = kzalloc(sizeof(*args), GFP_KERNEL);
 		if (!args) {
 			sock_shutdown(nbd);
+			/*
+			 * If num_connections is m (2 < m),
+			 * and NO.1 ~ NO.n(1 < n < m) kzallocs are successful.
+			 * But NO.(n + 1) failed. We still have n recv threads.
+			 * So, add flush_workqueue here to prevent recv threads
+			 * dropping the last config_refs and trying to destroy
+			 * the workqueue from inside the workqueue.
+			 */
+			if (i)
+				flush_workqueue(nbd->recv_workq);
 			return -ENOMEM;
 		}
 		sk_set_memalloc(config->socks[i]->sock->sk);