Subject: Re: [PATCH net v2 1/2] virtio_net: Do not set rss_indir if RSS is not supported

From: Breno Leitao <[email-masked]>
Date: Wed, 27 Mar 2024 06:51:25 -0700

Hello Xuan,

On Wed, Mar 27, 2024 at 09:37:43AM +0800, Xuan Zhuo wrote:
> On Tue, 26 Mar 2024 08:19:08 -0700, Breno Leitao <[email-masked]> wrote:
> > Do not set virtnet_info->rss_indir_table_size if RSS is not available
> > for the device.
> >
> > Currently, rss_indir_table_size is set if either has_rss or
> > has_rss_hash_report is available, but, it should only be set if has_rss
> > is set.
> >
> > On the virtnet_set_rxfh(), return an invalid command if the request has
> > indirection table set, but virtnet does not support RSS.
> >
> > Suggested-by: Heng Qi <[email-masked]>
> > Signed-off-by: Breno Leitao <[email-masked]>
> > ---
> >  drivers/net/virtio_net.c | 9 +++++++--
> >  1 file changed, 7 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> > index c22d1118a133..c640fdf28fc5 100644
> > --- a/drivers/net/virtio_net.c
> > +++ b/drivers/net/virtio_net.c
> > @@ -3813,6 +3813,9 @@ static int virtnet_set_rxfh(struct net_device *dev,
> >  	    rxfh->hfunc != ETH_RSS_HASH_TOP)
> >  		return -EOPNOTSUPP;
> >
> > +	if (rxfh->indir && !vi->has_rss)
> > +		return -EINVAL;
> > +
> >  	if (rxfh->indir) {
> 
> Put !vi->has_rss here?

I am not sure I understand the suggestion. Where do you suggest we have
!vi->has_rss?

If we got this far, we either have:

a) rxfh->indir set and vi->has_rss is also set
b) rxfh->indir not set. (vi->has_rss could be set or not).

Thanks for the review,
Breno