Re: [XEN PATCH v3] sbat: Add SBAT section to the Xen EFI binary

[Frediano Ziglio <frediano.ziglio@xxxxxxxxx>]

On Thu, May 8, 2025 at 12:55 PM Andrew Cooper <andrew.cooper3@xxxxxxxxxx> wrote:
>
> On 08/05/2025 11:31 am, Marek Marczykowski-Górecki wrote:
> > On Thu, May 08, 2025 at 09:51:59AM +0100, Andrew Cooper wrote:
> >> Also,
> >>
> >>> ld: warning: orphan section `.sbat' from `prelink.o' being placed in 
> >>> section `.sbat'
> >> This is because sbat.o is getting linked into the non-EFI build of Xen too.
> >>
> >> I'm less sure how to go about fixing this.  There's no nice way I can
> >> see of of getting sbat.o only in the EFI build.  The other option is to
> >> discard it for the ELF build.
> > This is kinda related to my question on Matrix - is multiboot2 binary
> > also supposed to (eventually) support UEFI SB?
>
> This is mixing two things.
>
> Xen is either an ELF binary (ultimately zipped, so xen.gz) or is an EFI
> binary (xen.efi).
>
> Both of these binaries currently have an MB2 header.  This was by
> accident, as xen.efi is a strict superset of the ELF build.
>

We are planning to use multiboot2 booting. The reason is the way we
want some parameters (like command line) to be passed. We are going to
use grub2.

> AIUI, SBAT only makes sense to exist in the EFI binary.
>
> ~Andrew

Frediano