On Wed, Jul 29, 2015 at 08:11:58PM +0300, Marcel Apfelbaum wrote:
> Complete vhost-user negotiation by syncing the features
> supported by the backend.
>
> Signed-off-by: Marcel Apfelbaum <mar...@redhat.com>
> ---
> To be used on top of:
> [PATCH 0/4] vhost-user: protocol updates
> https://lists.gnu.org/archive/html/qemu-devel/2015-07/msg03842.html
>
> Currently the vhost-user supported features are not evaluated.
> The way I see it, and please correct me, the best way to do
> this is to:
> 1. get the backend features on vhost init
> 2. Instead of simply copying them during features ack,
> check that that all backend features are supported by current QEMU
> 3. All other code should remain the same.
>
> Thanks,
> Marcel
>
> hw/net/vhost_net.c | 3 ++-
> hw/virtio/vhost-user.c | 4 ++--
> 2 files changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c
> index c864237..1ea5866 100644
> --- a/hw/net/vhost_net.c
> +++ b/hw/net/vhost_net.c
> @@ -118,7 +118,8 @@ uint64_t vhost_net_get_features(struct vhost_net *net,
> uint64_t features)
>
> void vhost_net_ack_features(struct vhost_net *net, uint64_t features)
> {
> - net->dev.acked_features = net->dev.backend_features;
> + vhost_ack_features(&net->dev, vhost_net_get_feature_bits(net),
> + net->dev.backend_features);
> vhost_ack_features(&net->dev, vhost_net_get_feature_bits(net), features);
So you ack it twice?
> }
>
> diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
> index c4428a1..077457b 100644
> --- a/hw/virtio/vhost-user.c
> +++ b/hw/virtio/vhost-user.c
> @@ -358,9 +358,9 @@ static int vhost_user_init(struct vhost_dev *dev, void
> *opaque)
> return err;
> }
>
> - if (__virtio_has_feature(msg.u64, VHOST_USER_F_PROTOCOL_FEATURES)) {
> - dev->backend_features |= 1ULL << VHOST_USER_F_PROTOCOL_FEATURES;
> + dev->backend_features = msg.u64;
>
> + if (__virtio_has_feature(msg.u64, VHOST_USER_F_PROTOCOL_FEATURES)) {
> msg.request = VHOST_USER_GET_PROTOCOL_FEATURES;
> msg.flags = VHOST_USER_VERSION;
> msg.size = 0;
> --
> 2.1.0
