> -----Original Message-----
> From: Maxime Coquelin <maxime.coque...@redhat.com>
> Sent: Thursday, May 5, 2022 6:27 PM
> To: dev@dpdk.org; jasow...@redhat.com; Xia, Chenbo <chenbo....@intel.com>;
> david.march...@redhat.com; olivier.m...@6wind.com
> Cc: sta...@dpdk.org; Maxime Coquelin <maxime.coque...@redhat.com>
> Subject: [PATCH 2/6] vhost: fix missing enqueue pseudo-header calculation
> 
> The Virtio specification requires that in case of checksum
> offloading, the pseudo-header checksum must be set in the
> L4 header.
> 
> When received from another Vhost-user port, the packet
> checksum might already contain the pseudo-header checksum
> but we have no way to know it. So we have no other choice
> than doing the pseudo-header checksum systematically.
> 
> This patch handles this using the rte_net_intel_cksum_prepare()
> helper.
> 
> Fixes: 859b480d5afd ("vhost: add guest offload setting")
> Cc: sta...@dpdk.org
> 
> Signed-off-by: Maxime Coquelin <maxime.coque...@redhat.com>
> ---
>  lib/vhost/virtio_net.c | 10 ++++++++++
>  1 file changed, 10 insertions(+)
> 
> diff --git a/lib/vhost/virtio_net.c b/lib/vhost/virtio_net.c
> index 5f432b0d77..c0ff3357a8 100644
> --- a/lib/vhost/virtio_net.c
> +++ b/lib/vhost/virtio_net.c
> @@ -548,6 +548,16 @@ virtio_enqueue_offload(struct rte_mbuf *m_buf, struct
> virtio_net_hdr *net_hdr)
>               csum_l4 |= RTE_MBUF_F_TX_TCP_CKSUM;
> 
>       if (csum_l4) {
> +             /*
> +              * Pseudo-header checksum must be set as per Virtio spec.
> +              *
> +              * Note: We don't propagate rte_net_intel_cksum_prepare()
> +              * errors, as it would have an impact on performance, and an
> +              * error would mean the packet is dropped by the guest instead
> +              * of being dropped here.
> +              */
> +             rte_net_intel_cksum_prepare(m_buf);
> +
>               net_hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
>               net_hdr->csum_start = m_buf->l2_len + m_buf->l3_len;
> 
> --
> 2.35.1

Reviewed-by: Chenbo Xia <chenbo....@intel.com>

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