On 2014/9/15 2:41, Michael S. Tsirkin wrote:
> From: Damjan Marion <damar...@cisco.com>
>
> Header length check should happen only if backend is kernel. For user
> backend there is no reason to reset this bit.
>
> vhost-user code does not define .has_vnet_hdr_len so
> VIRTIO_NET_F_MRG_RXBUF cannot be negotiated even if both sides
> support it.
>
> Signed-off-by: Damjan Marion <damar...@cisco.com>
> Reviewed-by: Michael S. Tsirkin <m...@redhat.com>
> Signed-off-by: Michael S. Tsirkin <m...@redhat.com>
> ---
> hw/net/vhost_net.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c
> index b21e7a4..77bb93e 100644
> --- a/hw/net/vhost_net.c
> +++ b/hw/net/vhost_net.c
> @@ -163,11 +163,11 @@ struct vhost_net *vhost_net_init(VhostNetOptions
> *options)
> if (r < 0) {
> goto fail;
> }
> - if (!qemu_has_vnet_hdr_len(options->net_backend,
> - sizeof(struct virtio_net_hdr_mrg_rxbuf))) {
> - net->dev.features &= ~(1 << VIRTIO_NET_F_MRG_RXBUF);
> - }
> if (backend_kernel) {
> + if (!qemu_has_vnet_hdr_len(options->net_backend,
> + sizeof(struct virtio_net_hdr_mrg_rxbuf))) {
> + net->dev.features &= ~(1 << VIRTIO_NET_F_MRG_RXBUF);
> + }
> if (~net->dev.features & net->dev.backend_features) {
> fprintf(stderr, "vhost lacks feature mask %" PRIu64
> " for backend\n",
>
why vhost-user code not define .has_vnet_hdr_len? I think vhost-user code
should define it.
if packet bigger than MTU,this will be a bug?
