RE: [PATCH v2 1/2] virtio-net: Fix receive buffer size calculation text

[Cornelia Huck <cohuck@redhat.com>]

On Tue, Jan 16 2024, Parav Pandit <parav@nvidia.com> wrote:

>> From: Cornelia Huck <cohuck@redhat.com>
>> Sent: Monday, January 15, 2024 10:14 PM
>
>> On Mon, Jan 15 2024, Parav Pandit <parav@nvidia.com> wrote:
>> > +The driver MUST consider size of field \field{struct virtio_net_hdr}
>> > +20 bytes if VIRTIO_NET_F_HASH_REPORT is negotiated, and 12 bytes if
>> not.
>> > +
>> 
>> Requiring the driver to consider the size of something to be its actual size
>> seems a bit odd :) I don't think we need this, as the length can be derived
>> from looking at the definitions, and is already spelled out explicitly, if you
>> consider my suggestion above.
> We need this because tx side also needs to refer to the virtio_net_hdr in patch 2 to be same as that of the rx side.
> And hence, this normative sets base line for tx side too. Relying on rest of the receive packet normative is not enough.

Hm, why? If struct virtio_net_hdr is well-defined, its size is
well-defined as well, and we do not need to state it explictly?