Re: [Qemu-devel] [PATCH V7 23/24] apci: fix PXB behaviour if used with unsupported BIOS

[Gerd Hoffmann]

On Mo, 2015-06-01 at 14:17 +0200, Michael S. Tsirkin wrote:
> On Mon, Jun 01, 2015 at 01:40:19PM +0200, Gerd Hoffmann wrote:
> > On Mo, 2015-06-01 at 12:44 +0300, Marcel Apfelbaum wrote:
> > > On 05/31/2015 09:12 PM, Michael S. Tsirkin wrote:
> > > > On Mon, May 25, 2015 at 06:34:01PM +0300, Marcel Apfelbaum wrote:
> > > >> PXB does not work with unsupported bioses, but should
> > > >> not interfere with normal OS operation.
> > > >> We don't ship them anymore, but it's reasonable
> > > >> to keep the work-around until we update the bios in qemu.
> > > >
> > > > We already did, did we not?
> > > Yes, we did, but Gerd preferred to keep this patch around.
> > > Adding him to thread.
> > 
> > seabios bundled with qemu isn't the only possible firmware.
> > 
> > We have ovmf, coreboot, qboot.
> 
> ovmf is especially interesting. Marcel, did you look at what
> happens with pxb and ovmf?
> 
> > You might boot with old seabios for
> > whatever reasons (say bisecting down something).
> 
> But then you won't have pxb, will you?

Devices behind pxb wouldn't be working because they didn't got resources
assigned, yes.  But at least the resources for the primary root bus
devices would not be screwed up like they are without this patch (IIRC).

cheers,
  Gerd