virtio: checksum error reported for ip6 traffic with GSO enable

When GSO is enabled, vhost clears the checksum field prior to transmitting
the packet. Some newer kernel version does not like that and complains
about checksum error. This was seen with ip6 traffic.

Type: fix

Signed-off-by: Steven Luong <sluong@cisco.com>
Change-Id: I7c6f2a6148f4a30107bfa8b078f5990e64300cf1
(cherry picked from commit ac0f5363881fdce2721287bc5c756282166d9991)

diff --git a/src/vnet/devices/virtio/vhost_user_input.c b/src/vnet/devices/virtio/vhost_user_input.c
index ea8e7d6..1209e13 100644 (file)
--- a/src/vnet/devices/virtio/vhost_user_input.c
+++ b/src/vnet/devices/virtio/vhost_user_input.c
@@ -292,15 +292,11 @@ vhost_user_handle_rx_offload (vlib_buffer_t * b0, u8 * b0_data,
       tcp_header_t *tcp = (tcp_header_t *)
        (b0_data + vnet_buffer (b0)->l4_hdr_offset);
       l4_hdr_sz = tcp_header_bytes (tcp);
-      tcp->checksum = 0;
       b0->flags |= VNET_BUFFER_F_OFFLOAD_TCP_CKSUM;
     }
   else if (l4_proto == IP_PROTOCOL_UDP)
     {
-      udp_header_t *udp =
-       (udp_header_t *) (b0_data + vnet_buffer (b0)->l4_hdr_offset);
-      l4_hdr_sz = sizeof (*udp);
-      udp->checksum = 0;
+      l4_hdr_sz = sizeof (udp_header_t);
       b0->flags |= VNET_BUFFER_F_OFFLOAD_UDP_CKSUM;
     }
 

diff --git a/src/vnet/devices/virtio/vhost_user_output.c b/src/vnet/devices/virtio/vhost_user_output.c
index 2d17ddf..54d478c 100644 (file)
--- a/src/vnet/devices/virtio/vhost_user_output.c
+++ b/src/vnet/devices/virtio/vhost_user_output.c
@@ -256,18 +256,12 @@ vhost_user_handle_tx_offload (vhost_user_intf_t * vui, vlib_buffer_t * b,
       hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
       hdr->csum_start = gho.l4_hdr_offset;
       hdr->csum_offset = offsetof (udp_header_t, checksum);
-      udp_header_t *udp =
-       (udp_header_t *) (vlib_buffer_get_current (b) + gho.l4_hdr_offset);
-      udp->checksum = 0;
     }
   else if (b->flags & VNET_BUFFER_F_OFFLOAD_TCP_CKSUM)
     {
       hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
       hdr->csum_start = gho.l4_hdr_offset;
       hdr->csum_offset = offsetof (tcp_header_t, checksum);
-      tcp_header_t *tcp =
-       (tcp_header_t *) (vlib_buffer_get_current (b) + gho.l4_hdr_offset);
-      tcp->checksum = 0;
     }
 
   /* GSO offload */