diff --git a/drivers/infiniband/hw/mlx4/main.c b/drivers/infiniband/hw/mlx4/main.c
index f07cbf8..3ae64ce 100644
--- a/drivers/infiniband/hw/mlx4/main.c
+++ b/drivers/infiniband/hw/mlx4/main.c
@@ -886,7 +886,7 @@
 		return -EOPNOTSUPP;
 
 	spin_lock_irqsave(&to_mdev(ibdev)->sm_lock, flags);
-	memcpy(ibdev->node_desc, props->node_desc, 64);
+	memcpy(ibdev->node_desc, props->node_desc, IB_DEVICE_NODE_DESC_MAX);
 	spin_unlock_irqrestore(&to_mdev(ibdev)->sm_lock, flags);
 
 	/*
@@ -897,7 +897,7 @@
 	if (IS_ERR(mailbox))
 		return 0;
 
-	memcpy(mailbox->buf, props->node_desc, 64);
+	memcpy(mailbox->buf, props->node_desc, IB_DEVICE_NODE_DESC_MAX);
 	mlx4_cmd(to_mdev(ibdev)->dev, mailbox->dma, 1, 0,
 		 MLX4_CMD_SET_NODE, MLX4_CMD_TIME_CLASS_A, MLX4_CMD_NATIVE);
 
@@ -2025,7 +2025,7 @@
 	if (err)
 		goto out;
 
-	memcpy(dev->ib_dev.node_desc, out_mad->data, 64);
+	memcpy(dev->ib_dev.node_desc, out_mad->data, IB_DEVICE_NODE_DESC_MAX);
 
 	in_mad->attr_id = IB_SMP_ATTR_NODE_INFO;