Re: [PATCH] x86/efistub: Omit physical KASLR when memory reservations exist

From: Kees Cook
Date: Thu May 16 2024 - 14:45:16 EST


On Thu, May 16, 2024 at 05:29:11PM +0000, Chaney, Ben wrote:
> > +static efi_status_t parse_options(const char *cmdline)
> > +{
> > + static const char opts[][14] = {
> > + "mem=", "memmap=", "efi_fake_mem=", "hugepages="
> > + };
> > +
>
> I think we probably want to include both crashkernel and pstore as arguments that can disable this randomization.

The carve-outs that pstore uses should already appear in the physical
memory mapping that EFI has. (i.e. those things get listed in e820 as
non-RAM, etc)

I don't know anything about crashkernel, but if we really do have a lot
of these, we likely need to find a way to express them to EFI...

--
Kees Cook