On 8/21/2021 12:42 AM, John Mok wrote:
Hi Chuck,
As a quick fix on the make installer media work, how can I remake my
own installation ISO by recompil ing the kernel and initramfs ?
Can give me some directions ?
Not yet regarding what kernel options are needed, because
I have not done any tests yet to see which kernel configuration
options or modules might be missing that are needed by the
Xen HVM.
A quick solution would not even require any recompilation
of a kernel, since we know the kernel and ramdisk of
an installed bullseye system does work in a Xen HVM guest.
Therefore...
if you can build an iso that is the same as the installation
iso in every way except that it boots using the default Debian kernel
and ramdisk on the final installed system instead of the stripped
down kernels/ramdisks on the installation media, you should get an
iso that can boot the debian installer in a Xen HVM guest.
I am not familiar with the process that the debian installer team
uses to generate the installation ISOs, but if I wanted to learn
I would start by looking at
https://wiki.debian.org/DebianInstaller/CheckOut
<https://wiki.debian.org/DebianInstaller/CheckOut>
and follow the instructions in the wiki checkout the source code
for the debian installer and from there you might be able to learn
how to build and modify a Debian installation ISO.
Regards,
Chuck
Chuck
Thanks a lot.
John Mok
On Sat, Aug 21, 2021, 12:08 Chuck Zmudzinski <brchu...@netscape.net
<mailto:brchu...@netscape.net>> wrote:
On 8/19/2021 3:11 PM, Andy Smith wrote:
> Hi Chuck,
>
> On Tue, Aug 17, 2021 at 08:04:43AM -0400, Chuck Zmudzinski wrote:
>> After some testing of the Debian 11 installer on Xen
>> (using the debian-11.0.0-amd64-netinst.iso), I find that
>> this image only supports installation into a Xen PV guest,
>> the guest always crashes and reboots for either a BIOS
>> or OVMF boot into an HVM Xen guest.
> Could you report this to Debian's Xen team as a bug? Perhaps it is
> as simple as needing different kernel options in the netinst
> installer kernel given that the full install works under HVM?
Hi Andy,
That is exactly what I think the problem is. I will look into it
and see if
there is a simple solution like adding the correct kernel
configuration
options and kernel modules to the kernel and ramdisk on the default
debian installer iso. The generic default amd64 iso should work in
Xen HVM guests.
>
> The Debian Xen team is very under-resourced for human help and it
> has been a long time since they have managed to keep the version in
> stable to a recent and supported one upstream. If you run a Xen dom0
> on Debian I think really you need to be building your own packages
> or using the Debian Xen team's packages from sid.
>
> The stable packaged 4.11 hypervisor is out of even security support
> upstream so it's not really suitable for production use.
With bullseye released, that is oldstable now. Xen 4.14 is on bullseye
and I think Xen 4.15 is the latest release upstream, so it is not
too far behind now. I presume Xen 4.14 is still getting security
patches
upstream, but I cannot find a good explanation of Xen's support
cycle on their website and I don't know if Debian can expect upstream
to support 4.14 until bullseye becomes oldstable in two years or so.
> I don't
> think the Debian Xen team would recommend using it but would instead
> suggest using their newer package that;s in sid (on stable) and
> test/report bigs against that. But let's get this reported.
If/when I find the solution, I will post a bug report and see if
the Xen
team can get the solution into the installer media for future bullseye
point releases. I already know the same problem exists on Xen 4.14
on bullseye, and AFAIK even sid has not bumped to 4.15 yet.
>
> I'm not skilled enough in Debian package building to help the team
> but I do still report bigs sometimes; for production use I am
> building packages from newer upstream source.
>
> For this problem I can't help as I don't run HVM guests (only PV and
> PVH).
I always had difficulty with pygrub/pvgrub on PV domains, and using
bullseye's Xen-4.14 version, I could not boot the debian installer iso
with pygrub but had to extract the xen-enabled kernel and ramdisk to
Dom0 and boot them from within Dom0. I think this is another Xen
bug in the Xen-4.14 package that I also will investigate next week.
Probably some tweaks to the pygrub script are needed there.
I have always wanted to try out PVH domains, but have not done so
yet.
>
> The Debian Xen team mailing list is at:
>
https://alioth-lists.debian.net/cgi-bin/mailman/listinfo/pkg-xen-devel
<https://alioth-lists.debian.net/cgi-bin/mailman/listinfo/pkg-xen-devel>
I will do some testing on this next week. I do want to help the
Xen team
make Debian more Xen-friendly and will report these bugs, hopefully
sometime next week.
Cheers,
Chuck
>
> Cheers,
> Andy
>