[PATCH V2 net-next 1/1] hyperv: Properly handle checksum offload

[K. Y. Srinivasan]

Do checksum offload only if the client of the driver wants checksum to be
offloaded.

In V1 version of this patch, I  addressed comments from
Stephen Hemminger <stephen at networkplumber.org> and
Eric Dumazet <eric.dumazet at gmail.com>.

In this version of the patch I have addressed comments from
David Miller.

This patch fixes a bug that is exposed in gateway scenarios.


Signed-off-by: K. Y. Srinivasan <kys at microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz at microsoft.com>
Cc: stable at kernel.org
---
 drivers/net/hyperv/netvsc_drv.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index 939e3af..64c7816 100644
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -467,6 +467,10 @@ static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net)
 	if (skb_is_gso(skb))
 		goto do_lso;
 
+	if ((skb->ip_summed == CHECKSUM_NONE) ||
+	    (skb->ip_summed == CHECKSUM_UNNECESSARY))
+		goto do_send;
+
 	rndis_msg_size += NDIS_CSUM_PPI_SIZE;
 	ppi = init_ppi_data(rndis_msg, NDIS_CSUM_PPI_SIZE,
 			    TCPIP_CHKSUM_PKTINFO);
-- 
1.7.4.1