Hello! Our setup ir probably antic but reliable. We build PV domU with xen-create-image (fuly automatic with Puppet).
Just today I built the first Jammy domU on a Jammy dom0 (Linux 5.15 with xen-hypervisor-4.16-amd64 and xen-tools 4.9.1). Building the domU worked fine, but I can not start the domU:
When using pygrub the error is:
xc: error: panic: xg_dom_bzimageloader.c:619: xc_try_zstd_decode: ZSTD decompress support unavailable
So it seems that pygrub does not support the ZSTD compressed kernel.
So I tried to boot the domU with pvgrub2 by setting:
kernel = "/usr/lib/grub-xen/grub-x86_64-xen.bin"
This brings me to a Grub shell, and manuall booting just leads to:
grub> linux /boot/vmlinuz root=/dev/xvda2
error: not xen image.
https://wiki.xenproject.org/wiki/Xen_Project_4.15_Feature_List states "Support for zstd-compressed dom0 (x86) and domU
kernels.".
So I need some advice/confirmations:
Can I boot Linux 5.15 (ZSTD kernel) with pygrub? If not, is it planned to add ZSTD support to pygrub?
If pygrub will not support ZSTD, what are my options? Should it work with pvgrub2 and I am doing something wrong? How to correctly use pvgrub2.
If pvgrub2 does not support ZSTD, what are my options? Would it help to move from PV to PVH,PVHVM,…? Can I automate building domUs similar to xen-create-image also with non-PV domUs?
Thanks
Klaus
