Re: mm/hwpoison: persist poisoned PFN list across kexec via KHO [RFC]

On Wed, Jun 24, 2026 at 08:21:16AM -0700, Breno Leitao wrote:
> > > Possible solutions
> > > ==================
> > ...
> > > 
> > > 2. e820 / EFI memory map (E820_TYPE_UNUSABLE). Tempting because the
> > >    frame would simply never become RAM (no allocator race at all).
> > >    But: it is x86-only (no arm64 equivalent in the same mechanism;
> > >    this series is tested on arm64);
> > 
> > (+Ard. I might get some details around EFI wrong.)
> > 
> > This isn't accurate, and I think it's the right direction for EFI
> > platforms. EFI_UNUSABLE_MEMORY is honored on both arches today, no new
> > consumer code:
> > 
> >   - arm64: reserve_regions() marks non-usable memory nomap.
> 
> Is it true for non-UEFI arm64 hosts?

No. It is EFI-only thingy.

Is there non-EFI server platforms worth caring about?

-- 
  Kiryl Shutsemau / Kirill A. Shutemov