--- a/drivers/net/ethernet/broadcom/bcm63xx_enet.c
+++ b/drivers/net/ethernet/broadcom/bcm63xx_enet.c
@@ -1515,7 +1515,7 @@ static int compute_hw_mtu(struct bcm_ene
 	actual_mtu = mtu;
 
 	/* add ethernet header + vlan tag size */
-	actual_mtu += VLAN_ETH_HLEN;
+	actual_mtu += VLAN_ETH_HLEN + VLAN_HLEN;
 
 	if (actual_mtu < 64 || actual_mtu > BCMENET_MAX_MTU)
 		return -EINVAL;
