Re: Pvgrub with lz4 compressed kernels

[Andy Smith <andy@xxxxxxxxxxxxxx>]

Hi John,

On Fri, May 01, 2020 at 04:23:29AM +0000, John S wrote:
> I am running PV guests on xen 4.11 with pvgrub. The recent
> releases of ubuntu (>19.04) look to have switched to lz4
> compressed kernels. These kernels work fine with direct boot, but
> under pvgrub and pvgrub2 they don't seem bootable.

I have the same problem. I don't believe there is any support in
Grub for it yet. I asked but have not got a response yet:

    https://lists.gnu.org/archive/html/grub-devel/2020-04/msg00198.html

If you see my own response to my email, I found that Grub compiled
as a PVH image will boot these kernels in PVH mode.

The other thing you can do right now is decompress the kernel images
using:

    
https://raw.githubusercontent.com/torvalds/linux/master/scripts/extract-vmlinux

They will then boot with pvgrub.

For those of us not yet ready to switch to PVH it would be great if
someone could implement LZ4 decompression for pvgrub.

Cheers,
Andy