diff --git a/drivers/net/ethernet/mellanox/mlx4/mr.c b/drivers/net/ethernet/mellanox/mlx4/mr.c
index 78f51e1..9319519 100644
--- a/drivers/net/ethernet/mellanox/mlx4/mr.c
+++ b/drivers/net/ethernet/mellanox/mlx4/mr.c
@@ -318,7 +318,7 @@
 				key, NULL);
 	} else {
 		mailbox = mlx4_alloc_cmd_mailbox(dev);
-		if (IS_ERR_OR_NULL(mailbox))
+		if (IS_ERR(mailbox))
 			return PTR_ERR(mailbox);
 
 		err = mlx4_cmd_box(dev, 0, mailbox->dma, key,