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Date:   Sat, 8 Oct 2022 17:51:30 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Ard Biesheuvel <ardb@kernel.org>
Cc:     linux-efi@vger.kernel.org, x86@kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] efi: x86: Make the deprecated EFI handover protocol
 optional
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On Sat, Oct 08, 2022 at 05:41:40PM +0200, Ard Biesheuvel wrote:
> Yeah most distros have ~100 ore more patches against GRUB, but this
> isn't actually their fault. GRUB maintainership was defunct for a
> number of years, which is why we were stuck on GRUB version 2.02-beta3
> for such a long time. But in recent years, things have been getting
> better, and there is an agreement with the current maintainer not to
> merge the EFI handover protocol, and merge the new EFI protocol based
> initrd loading method instead, which works on all architectures
> instead of only on x86.

Aha, ok.

> Never tried that in .S files but I guess it should just work.

If not, at least in the .c files.

> I'd venture a guess that this will break the boot even your own x86
> boxes, given that almost nobody uses plain upstream GRUB..
> 
> I can work with the distros directly to start disabling this in their
> downstream configs once their GRUB builds are up to date with the new
> changes, so we can phase this out in a controlled manner.

Hm, that might turn out to be a multi-year effort considering how the
enterprise distros' kernels are moving. Yeah, yeah, they have good
reasons and so on.

> But disabling tthis right now by default is going to affect everyone
> who builds their own kernels and runs them on a distro Linux install.

Ok, I can try it on my SUSE and Debian partitions and see what happens.

Thx.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette