On Wed, Feb 25, 2026 at 12:29:41PM +0000, Srujana Challa wrote:
> > > > patch 1 is unreasonable i think.
> > >
> > > Patch 1 is targeted for net, addressing an issue where
> > > VIRTIO_NET_RSS_MAX_KEY_SIZE is fixed at 40, which is only the minimum
> > > required by the spec. This led to virtio‑net probe failures when
> > > devices reported an RSS key size greater than 40. However, the driver
> > > also cannot handle keys larger than NETDEV_RSS_KEY_LEN (previously 52)
> > > due to the BUG_ON(len > sizeof(netdev_rss_key)) in netdev_rss_key_fill. To
> > resolve both issues, VIRTIO_NET_RSS_MAX_KEY_SIZE has been replaced with
> > NETDEV_RSS_KEY_LEN.
> >
> > but where would driver *get* keys larger than sizeof(netdev_rss_key), even
> > if
> > device supports more.
> In virtio‑net, we rely on netdev_rss_key_fill() during
> virtnet_init_default_rss() to populate the RSS hash key,
> which uses device supported length.
> The code path is:
> static void virtnet_init_default_rss(struct virtnet_info *vi)
> {
> vi->rss_hdr->hash_types = cpu_to_le32(vi->rss_hash_types_supported);
> vi->rss_hash_types_saved = vi->rss_hash_types_supported;
> vi->rss_hdr->indirection_table_mask = vi->rss_indir_table_size
> ?
> cpu_to_le16(vi->rss_indir_table_size - 1) : 0;
> vi->rss_hdr->unclassified_queue = 0;
>
> virtnet_rss_update_by_qpairs(vi, vi->curr_queue_pairs);
>
> vi->rss_trailer.hash_key_length = vi->rss_key_size;
>
> netdev_rss_key_fill(vi->rss_hash_key_data, vi->rss_key_size);
> }
Is there a point you are trying to make? disabling features because user
bought a stronger device is counter intuitive. Make it work
in a sane way pls.
--
MST
