[PATCH net-next 2/3] be2net: Pad skb to meet min Tx pkt size in lancer

[PATCH net-next 2/3] be2net: Pad skb to meet min Tx pkt size in lancer

[Somnath Kotur]

In Lancer, packets that are 32 bytes or less may cause a transmit stall.
The work-around is to pad such packets to a 36 byte length.

Signed-off-by: Kalesh AP <kalesh.purayil@emulex.com>
Signed-off-by: Somnath Kotur <somnath.kotur@emulex.com>
---
 drivers/net/ethernet/emulex/benet/be_main.c |   10 ++++++++++
 1 files changed, 10 insertions(+), 0 deletions(-)

diff --git a/drivers/net/ethernet/emulex/benet/be_main.c b/drivers/net/ethernet/emulex/benet/be_main.c
index 0f21c35..a1b9474 100644
--- a/drivers/net/ethernet/emulex/benet/be_main.c
+++ b/drivers/net/ethernet/emulex/benet/be_main.c
@@ -856,6 +856,16 @@ static struct sk_buff *be_xmit_workarounds(struct be_adapter *adapter,
 	unsigned int eth_hdr_len;
 	struct iphdr *ip;
 
+	/* Lancer ASIC has a bug wherein packets that are 32 bytes or less
+	 * may cause a transmit stall on that port. So the work-around is to
+	 * pad such packets to a 36-byte length.
+	 */
+	if (unlikely(lancer_chip(adapter) && skb->len <= 32)) {
+		if (skb_padto(skb, 36))
+			goto tx_drop;
+		skb->len = 36;
+	}
+
 	/* For padded packets, BE HW modifies tot_len field in IP header
 	 * incorrecly when VLAN tag is inserted by HW.
 	 */
-- 
1.5.6.1