diff --git a/drivers/infiniband/hw/mlx4/mad.c b/drivers/infiniband/hw/mlx4/mad.c
index 08eccf2b6967..511e095aa556 100644
--- a/drivers/infiniband/hw/mlx4/mad.c
+++ b/drivers/infiniband/hw/mlx4/mad.c
@@ -2167,7 +2167,7 @@ static int mlx4_ib_alloc_demux_ctx(struct mlx4_ib_dev *dev,
 				       struct mlx4_ib_demux_ctx *ctx,
 				       int port)
 {
-	char name[12];
+	char name[21];
 	int ret = 0;
 	int i;