gianfar: only check headroom when FCB is needed

Signed-off-by: Li Yang <leoli@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 2 deletions

diff --git a/drivers/net/gianfar.c b/drivers/net/gianfar.c
index 44cbf2622b46..6a38800be3f1 100644
--- a/drivers/net/gianfar.c
+++ b/drivers/net/gianfar.c
@@ -1310,8 +1310,10 @@ static int gfar_start_xmit(struct sk_buff *skb, struct net_device *dev)
 
         base = priv->tx_bd_base;
 
-        /* make space for additional header */
-        if (skb_headroom(skb) < GMAC_FCB_LEN) {
+        /* make space for additional header when fcb is needed */
+        if (((skb->ip_summed == CHECKSUM_PARTIAL) ||
+                        (priv->vlgrp && vlan_tx_tag_present(skb))) &&
+                        (skb_headroom(skb) < GMAC_FCB_LEN)) {
                 struct sk_buff *skb_new;
 
                 skb_new = skb_realloc_headroom(skb, GMAC_FCB_LEN);