[virtio-dev] RE: [PATCH v2 0/2] transport-pci: Introduce legacy registers access using AQ

Parav Pandit
2023-05-15T18:05:48Z

> From: Michael S. Tsirkin <mst@redhat.com>
> Sent: Monday, May 15, 2023 2:02 PM
> > >
> > How can it be required if it not part of it?
> > I likely didn't follow your question/comment, can you please explain.
>
> VIRTIO_F_NOTIF_CONFIG_DATA is there presumably for a reason.
The discussion is for the legacy interface for which CONFIG_DATA doesn't exist.

>
> > > > For modern device, guest driver will access the device own BAR
> > > > directly with
> > > its own config_data anyway.
> > > > Should we reserve a region in the PF BAR for SF/SIOV device?,
> > > > should device
> > > report which BAR/area to use for the given SF/SIOV device?
> > > > May be yes, those are different discussions with tradeoff to
> > > > consider during
> > > SIOV discussions. It is not related to VFs.
> > >
> > > For SIOV it's a given. But we can do this for SRIOV: reserve a PF region per
> VF.
> > Each VF has its own BAR area for driver notifications.
>
> But it is passed through to guest presumably.
Yes, so?