As PKT_TX_TCP_SEG flag in mbuf->ol_flags implies PKT_TX_TCP_CKSUM,
applications, e.g., testpmd, don't set PKT_TX_TCP_CKSUM when TSO
is set.
This leads to that packets get dropped in VM tcp stack layer because
of bad TCP csum.
To fix this, we make sure TCP NEEDS_CSUM info is set into virtio net
header when PKT_TX_TCP_SEG is set, so that VM tcp stack will not
check the TCP csum.
Fixes: 859b480d5afd ("vhost: add guest offload setting")
Cc: sta...@dpdk.org
Cc: Yuanhan Liu <yuanhan....@linux.intel.com>
Cc: Maxime Coquelin <maxime.coque...@redhat.com>
Cc: Jiayu Hu <jiayu...@intel.com>
Signed-off-by: Jianfeng Tan <jianfeng....@intel.com>
---
lib/librte_vhost/virtio_net.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c
index 48219e0..0a7e023 100644
--- a/lib/librte_vhost/virtio_net.c
+++ b/lib/librte_vhost/virtio_net.c
@@ -114,11 +114,16 @@ update_shadow_used_ring(struct vhost_virtqueue *vq,
static void
virtio_enqueue_offload(struct rte_mbuf *m_buf, struct virtio_net_hdr *net_hdr)
{
- if (m_buf->ol_flags & PKT_TX_L4_MASK) {
+ uint64_t csum_l4 = m_buf->ol_flags & PKT_TX_L4_MASK;
+
+ if (m_buf->ol_flags & PKT_TX_TCP_SEG)
+ csum_l4 |= PKT_TX_TCP_CKSUM;
+
+ if (csum_l4) {
net_hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
net_hdr->csum_start = m_buf->l2_len + m_buf->l3_len;
- switch (m_buf->ol_flags & PKT_TX_L4_MASK) {
+ switch (csum_l4) {
case PKT_TX_TCP_CKSUM:
net_hdr->csum_offset = (offsetof(struct tcp_hdr,
cksum));
--
2.7.4
