Re: [Qemu-devel] [v5][PATCH 0/5] xen: add Intel IGD passthrough support

[Michael S. Tsirkin]

On Wed, Jun 25, 2014 at 03:53:30PM +0200, Paolo Bonzini wrote:
> Il 25/06/2014 15:47, Michael S. Tsirkin ha scritto:
> >OK, so how about doing this: either for the ISA
> >bridge, or for the VGA card itself:
> >
> >    set subsystem vendor id to PCI_VENDOR_ID_XEN,
> >    set subsystem device id to PCH device id
> 
> That would work, but the same problem would then arise for the MCH.  The
> driver there is banging at random places in the configuration space.
> 
> This is why I asked for a solution that is future-proof, and since you can
> make one that works for both MCH and PCH it is nice to do the work just
> once.
> 
> Paolo

Q35 has MCH, so I don't see why we can't make that work,
extending it as appropriate.
Doing that for PIIX is iffy.
Should we really do that? Q35 is there.

-- 
MST