Re: [PATCH 0/1] x86/kexec: UKI support

From: Jan Hendrik Farr
Date: Sat Sep 09 2023 - 13:59:24 EST


> - the cmdline section is actually optional, just like it's optional to
> pass it on a traditional kexec load, so it should be used if present,
> but skipped if not

Should be an easy fix.

This should be updated in the UKI documentation as for other optional sections it's explicitly marked. I assumed that in the case of an empty cmdline the section would still be included but empty. Or is that semantically different: empty .cmdline section -> no cmdline allowed, no .cmdline section -> user can specify cmdline in bootloader?

> - the dtb section also is optional but supported, and given kexec
> supports loading a new dtb I think this change should support it too
> immediately. Moreover, we are adding support for multiple DTBs in a
> single UKI (by simply having multiple .dtb sections, and picking the
> one that matches the firmware), as a stretch goal would be nice to
> support that too, but it can also come later

As far as I know dtb is not supported by kexec_file_load at all at the moment. Maybe someone here knows more about this. I'll look into it.

> - also what would it take to support arm64, which is the other major UEFI arch?

I'm not familiar with UEFI on arm64, but I can certainly look into it. I assume it's not gonna be that difficult.