Re: qemu-xen-staging v7.0.0, FTBFS in Bullseye, deb11

[Chuck Zmudzinski <brchuckz@xxxxxxxxxxxx>]

On 8/13/22 11:29 PM, Pry Mar wrote:
> Hello,
>
> https://lists.nongnu.org/archive/html/qemu-devel/2022-07/msg04911.html
>
> I rebased the xen-4.16.1.tar.gz release with the qemu-xen v7.0.0 from staging.
>
> http://xenbits.xen.org/gitweb/?p=qemu-xen.git;a=shortlog;h=refs/heads/staging
>
> I built this in AlmaLinux 9 and Jammy 22.04 without trouble, however
> in Bullseye I could not get past errors like shown in qemu-devel post
> above.
>
> > ../ui/dbus.c: In function ‘dbus_create_context’:
> > ../ui/dbus.c:47:20: error: ‘qemu_egl_rn_ctx’ undeclared (first use in this
> > function); did you mean ‘qemu_egl_init_ctx’?
> >    47 |                    qemu_egl_rn_ctx);
> >       |                    ^~~~~~~~~~~~~~~
> >       |                    qemu_egl_init_ctx
> > ../ui/dbus.c:47:20: note: each undeclared identifier is reported only once
> > for each function it appears in
> >
> > and many other similar errors, because include/ui/egl-helpers.h only has
> > these declaration if gbm is found on the system.
> >
> > Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
>
> `D-bus display` is a new feature in qemu v7.0.0 and they are showing
> errors still 3 months after release.
>
> The patch they proposed is indexed at 3285 past the v7.0.0 release! It
> seemed impossible to put together a backported patchset that includes
> their fix.
>
> Nevertheless I found 5/3285 patches that could backport and get past FTBFS.
> They are attached along with the Meson metainfo for the Bullseye qemu build.
>
> I have used this patchset using the quilt, git am, and rpm patching
> systems and I trust it will work anywhere on the qemu-xen tree.
>
> cheers,
> PryMar56

Thank you for this interesting information, but...

I am not sure I understand the significance of this information for
users of the Debian Bullseye packages of Xen and Qemu.

This information might be useful for some purposes on Debian 11
stable aka Bullseye but Debian does not support running Xen 4.16.x on
Bullseye, because the Xen package for Debian 11 Bullseye is Xen 4.14.x,
not Xen 4.16.x, and also the package for Qemu on Debian 11 Bullseye is
fairly old, Qemu 5.2, not Qemu 7.0. Debian does provide a backported
version of Qemu 7.0 for Bullseye but that is only supported with Xen 4.14,
not Xen 4.16, on Debian Bullseye. Are you saying that Debian should
use your five patches instead of the patches they are currently using
to deliver their backported version of Qemu 7.0 for Debian Bullseye?
Do your five patches fix some bug on Debian Bullseye or add some
feature that is currently missing from Debian Bullseye, such as the new
D-Bus display feature in Qemu 7.0?

The current supported way to run Xen-4.16/Qemu 7.0 on Debian is
to use Debian testing, aka Bookworm, which when released will be
Debian 12, or to use Debian unstable, aka Debian Sid. Have you tested
the build of qemu-xen-staging v7.0.0 on Debian Bookworm or Debian Sid?
That would be more interesting to me as a Debian user going forward than
fixing an FTBFS on Debian Bullseye that does not clearly add any benefit
to users of Debian Bullseye.

If by using your proposed patch set for Qemu 7.0 on Bullseye instead
of Debian's official backported version of Qemu 7.0 for Bullseye something
is fixed such as a bug or the new D-Bus display feature is added to Debian
Bullseye, then this might be of interest to me as a user of Debian Bullseye
and Debian's Xen and Qemu packages for Bullseye.

Best regards,

Chuck