RDMA/nes: Fix for crash when TX checksum offload is off

When TX checksum offload is disabled for an iWarp connection,
skb->ip_summed needs to be set to CHECKSUM_NONE.

Signed-off-by: Tatyana Nikolova <Tatyana.E.Nikolova@intel.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

drivers/infiniband/hw/nes/nes_cm.c

@@ -430,6 +430,8 @@ static void form_cm_frame(struct sk_buff *skb,
 	buf += sizeof(*tcph);
 
 	skb->ip_summed = CHECKSUM_PARTIAL;
+	if (!(cm_node->netdev->features & NETIF_F_IP_CSUM))
+		skb->ip_summed = CHECKSUM_NONE;
 	skb->protocol = htons(0x800);
 	skb->data_len = 0;
 	skb->mac_len = ETH_HLEN;