Re: [PULL 0/2] Seabios 1.17.0 20250611 patches

[Stefan Hajnoczi <stefanha@gmail.com>]

On Thu, Jun 12, 2025 at 6:16 AM Daniel P. Berrangé <berrange@redhat.com> wrote:
>
> On Wed, Jun 11, 2025 at 03:21:38PM -0400, Stefan Hajnoczi wrote:
> > On Wed, Jun 11, 2025 at 2:03 PM Daniel P. Berrangé <berrange@redhat.com> wrote:
> > >
> > > FYI, this seabios 1.17.0 release appears to have broken the
> > > ability to use virtio-pci with libguestfs+QEMU:
> > >
> > >   https://bugzilla.redhat.com/show_bug.cgi?id=2372329
> > >
> > > so I'd suggest we hold off on this pull request until
> > > the regression is diagnosed.
> >
> > Thanks, Daniel. I have pushed a revert to staging.
>
> This has been diagnosed now.
>
> Old SeaBIOS would unconditionally add ACPI tables, even when QEMU
> machine type had acpi=off. libguestfs forgot to ask for ACPI in
> its libvirt XML, so was getting acpi=off as far as QEMU was
> concerned, but SeaBIOS was none the less creating ACPI tables.
>
> It was a miracle this worked because the ACPI tables were
> designed for i440fx, but somehow Linux still booted with
> them under q35.
>
> So, the SeaBIOS update has a functional change, but that
> was intentional & desirable, and the root bug was the lack
> of request for ACPI in libguestfs.
>
> So no need to revert anything

Thanks for the update!

Stefan