From mboxrd@z Thu Jan  1 00:00:00 1970
From: Borislav Petkov <bp-Gina5bIWoIWzQB+pC5nmwQ@public.gmane.org>
Subject: Re: [PATCH 1/2] x86/boot/compressed/64: Remove .bss/.pgtable from
 bzImage
Date: Mon, 6 Apr 2020 19:21:02 +0200
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To: Ard Biesheuvel <ardb-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, Arvind Sankar <nivedita-FrUbXkNCsVf2fBVCVOL8/A@public.gmane.org>
Cc: Sergey Shatunov <me-fHUSW+XspFU@public.gmane.org>, hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org, Linux Kernel Mailing List <linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, mingo-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, Thomas Gleixner <tglx-hfZtesqFncYOwBW4kG4KsQ@public.gmane.org>, x86-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, linux-efi <linux-efi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, initramfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Donovan Tremura <neurognostic-g/b1ySJe57IkP3XJZ0H8fw@public.gmane.org>, Harald Hoyer <harald-PnQE6hpDOpmlVyrhU4qvOw@public.gmane.org>

On Mon, Apr 06, 2020 at 03:29:18PM +0200, Ard Biesheuvel wrote:
> > What do you think of the other problem -- that's actually worse to fix,
> > as it won't just be when kaslr is disabled, the startup_64 code will do
> > relocation to the end of init_size and clobber the initrd before getting
> > to the kaslr code, so it will break as soon as the firmware loads the
> > "unified kernel image" at a 2Mb-aligned address. The only thing I can
> > think of is to just unconditionally call efi_relocate_kernel if we were
> > entered via handover_entry?
> >
> 
> Yes, that seems to be the most robust approach.

The commit in question is this one:

d5cdf4cfeac9 ("efi/x86: Don't relocate the kernel unless necessary")

I presume?

I'm guessing it can simply be reverted as it doesn't fix a bug but it is
just an optimization... provided I'm not missing something, of course.

-- 
Regards/Gruss,
    Boris.

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