Re: Grub xen_pvh platform does not seem to support uncompressed kernels

[Bastian Blank <bblank@xxxxxxxxxx>]

On Mon, Nov 02, 2020 at 08:27:23AM +0000, Andy Smith wrote:
> The decompressed kernel is generated like this:
> # extract-vmlinux /boot/vmlinuz-5.4.0-52-generic > 
> /boot/vmlinuz-5.4.0-52-generic-decompressed

vmlinuz contains two parts:
- the x86 boot code and
- the compressed ELF file.

extract-vmlinux extracts and decompresses the second part.  But it can't
restore the boot code, which is required to make this file actually
bootable in normal conditions.

> The decompressed kernel does boot when presented to the hypervisor
> directly, i.e. no grub, directly listed in guest config file.

Because Xen extracts and boots the ELF file embedded in the file without
any help of the x86 boot code.

> So, is this a bug? Grub should be able to boot uncompressed kernels,
> shouldn't it?

No, at least not the one you gave it on x86.

Regards,
Bastian

-- 
It is undignified for a woman to play servant to a man who is not hers.
                -- Spock, "Amok Time", stardate 3372.7