Re: [virtio-comment] [PATCH v4 1/1] virtio-net: Define per-packet hash reporting feature

["Michael S. Tsirkin" <mst@redhat.com>]

On Wed, Feb 19, 2020 at 08:27:10PM +0800, Jason Wang wrote:
> 
> On 2020/2/19 äå3:53, Yuri Benditovich wrote:
> >   The device MUST set \field{rss_max_indirection_table_length} to at least 128, if it offers
> >   VIRTIO_NET_F_RSS.
> > @@ -3195,6 +3180,8 @@ \subsection{Device Operation}\label{sec:Device Types / Network Device / Device O
> >           le16 csum_start;
> >           le16 csum_offset;
> >           le16 num_buffers;
> > +        le32 hash_value; (Only if VIRTIO_NET_F_HASH_REPORT negotiated)
> > +        le16 hash_type;  (Only if VIRTIO_NET_F_HASH_REPORT negotiated)
> >   };
> >   \end{lstlisting}
> 
> 
> A question here:
> 
> Consider we introduce VIRTIO_NET_F_FEATURE_INFORMATION in the future:
> 
> le32 hash_type; // VIRTIO_NET_F_HASH_REPORT
> le32 feature_information; // VIRTIO_NET_F_FEATURE_INFORMATION
> 
> What happens if HASH_REPORT is not negotiated, I believe we expect a stable
> ABI(offset) here for feature_information?
> 
> Thanks
> 

We'll have to decide at that point ... any better ideas?

-- 
MST