Re: bug, bad page free with hvm guest after commits about AMD IOMMU

[Wei Wang2 <wei.wang2@amd.com>]

On Thursday 05 May 2011 16:44:36 Tim Deegan wrote:
> CC'ing John and George, who reported similar-sounding failures.
>
> At 14:56 +0100 on 05 May (1304607375), Anthony Perard wrote:
> > On Thu, May 5, 2011 at 14:40, Tim Deegan <Tim.Deegan@citrix.com> wrote:
> > > At 14:31 +0100 on 05 May (1304605909), Anthony PERARD wrote:
> > >> Hi,
> > >>
> > >> With the last xen-unstable, when I try to run a HVM guest, the vgabios
> > >> did not display anything on the screen (it is only white), and Xen
> > >> print this:
> > >
> > > Interesting.  I get those messages but the BIOS continues OK so I
> > > hadn't been in a hurry to investigate.  I'll take a look.
> >
> > Yes, the guest works fine after that, but on linux, there is no vga
> > console, but a X server work fine.
>
> I suspect it's the use of type 0 to mean RAM: it means that an entry of
> all zeroes no longer gives type mmio so something's not going to qemu
> correctly.
>
> Does the attached patch fix it for you?  I'm still seeing intermittent
> failures with it but they may be unrelated.
Tim,
This patch works well with AMD. Thanks!
Wei

> Tim.