Re: [PATCH v3] x86/e820: Fix handling of subpage regions when calculating nosave ranges

[Ingo Molnar <mingo@kernel.org>]

* Myrrh Periwinkle <myrrhperiwinkle@qtmlabs.xyz> wrote:

> The current implementation of e820__register_nosave_regions suffers from
> multiple serious issues:
>  - The end of last region is tracked by PFN, causing it to find holes
>    that aren't there if two consecutive subpage regions are present
>  - The nosave PFN ranges derived from holes are rounded out (instead of
>    rounded in) which makes it inconsistent with how explicitly reserved
>    regions are handled
> 
> Fix this by:
>  - Treating reserved regions as if they were holes, to ensure consistent
>    handling (rounding out nosave PFN ranges is more correct as the
>    kernel does not use partial pages)
>  - Tracking the end of the last RAM region by address instead of pages
>    to detect holes more precisely
> 
> Cc: stable@vger.kernel.org
> Fixes: e5540f875404 ("x86/boot/e820: Consolidate 'struct e820_entry *entry' local variable names")

So why is this SHA1 indicated as the root cause? AFAICS that commit 
does nothing but cleanups, so it cannot cause such regressions.

Thanks,

	Ingo