Re: [Qemu-devel] vfio IGD assignment (was Re: [PATCH v6 0/8] Series short description)

Gerd Hoffmann
2016-05-20T12:19:23Z

On Mi, 2016-05-18 at 12:45 -0600, Alex Williamson wrote:
> On Wed, 18 May 2016 16:24:49 +0200
> Gerd Hoffmann <kraxel@redhat.com> wrote:
>
> > Hi,
> >
> > > I believe we're no longer blocked by SeaBIOS being willing to
> > > consume the new fw_cfg entries, so barring feedback otherwise, my
> > > plan will be to send a pull request including these changes (after
> > > an appropriate review period), ask Kevin to apply the matching
> > > SeaBIOS change, then see if Gerd will help me pull that support
> > > into the default QEMU SeaBIOS image.
> >
> > Sounds good. Patches look sane to me too.
> >
> > Will try to set aside some time to test them later this week (and also
> > push a branch with updated seabios etc for others to try).
>
> Thanks Gerd!

Works flawlessly.

Linux works fine with the igd assigned as primary (pc machine type and
igd using slot 2).

Linux doesn't work in UPT mode for me. That is more a guest driver
issue though. The i915 driver of older kernels Oopses. The i915 driver
of recent kernels (4.4.5+) loads fine on q35, but fails to drive my
monitor, no matter whenever I enable the opregion or not. For pc an
additional kernel patch is needed (which hopefully lands upstream soon)
to reach feature parity (as-in: no Oops on load) with q35.

For windows UPT mode is the only thing supported by the drivers. Needs
the opregion enabled to show something on the connected display. Works
fine on both pc and q35, in parallel with a emulated display, and you
can configure things as you want (mirror, expand desktop, use only one
of the displays).

Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Tested-by: Gerd Hoffmann <kraxel@redhat.com>

cheers,
Gerd