Re: [PATCH v19] virtio-net: support inner header hash

[Jason Wang <jasowang@redhat.com>]

On Wed, Jun 28, 2023 at 12:23âPM Parav Pandit <parav@nvidia.com> wrote:
>
>
> > From: Jason Wang <jasowang@redhat.com>
> > Sent: Tuesday, June 27, 2023 11:46 PM
> >
> > Having it in the config space, then a type agnostic provisioning through config
> > space + feature bits just works fine.
> >
> Provisioning is far simpler thing to do in device specific way than asking device to store this value in onchip area which is rarely accessed.

Are you suggesting to not place any new fields in the config space?

struct virtio_net_config {
        u8 mac[6];
        le16 status;
        le16 max_virtqueue_pairs;
        le16 mtu;
        le32 speed;
        u8 duplex;
        u8 rss_max_key_size;
        le16 rss_max_indirection_table_length;
        le32 supported_hash_types;
};

Which of the above do you think can be accessed frequently and which
part of the spec says it must be stored in the onchip area?

Thanks

> There are many fields of many features for 1.4 are discussed including this one. All of these capabilities just cannot be stored in config space.
>
> > If we move it only via cvq, we need device specific provisioning interface.