RE: [virtio-dev] Re: [virtio-comment] Re: [PATCH v7] virtio-net: support inner header hash

[Parav Pandit <parav@nvidia.com>]

> From: Heng Qi <hengqi@linux.alibaba.com>
> Sent: Tuesday, February 7, 2023 10:25 PM

[..]
> >>
> >> Do you think we need both hash_types and hash_tunnel_types?
> > In struct virtio_net_config we need two fields.
> > a. supported_hash_types (already exists) b. supported_hash_tunnel_type
> > -> bitmap indicating for which outer headers, inner hash calculation is
> supported.
> 
> Thanks for the suggestion, we seem to have reached an agreement.
> 
> >
> > In struct virtio_net_hdr we need two fields.
> > a. hash_report (already exists)
> > b. hash_tunnel_type 8 bits -> absolute value indicating which outer header
> exists when inner header hash calculated.
> > You already have it in your patch named as hash_report_tunnel.
> > May be better to name as hash_report_tunnel_type to make it clearer that its
> type.
> 
> Sure.
> 
> Thanks for your reply.

I had one last question. Why do we need to inform the hash_report_tunnel_type of the outer header in the virtio_net_hdr?
Is this for debug? Or is there a use case that will process this value?