Re: [PATCH v2] x86/sev: Apply the RMP table e820 fixups before memblock is populated

From: Tom Lendacky

Date: Wed Oct 21 2026 - 09:42:29 EST


On 10/20/26 22:49, Borislav Petkov wrote:
> On Tue, Oct 20, 2026 at 08:28:18PM +0000, Ashish Kalra wrote:
>> From: Ashish Kalra <ashish.kalra@xxxxxxx>
>>
>> When the start and/or end of the RMP table is not 2MB aligned,
>
> When is that the case? Why aren't they? Why doesn't firmware align them?

It is actually quite common with the contiguous RMP and a bit less with
the segmented RMP as the RMP segments tend to be aligned, but the RMP
segment table tends not to be.

We can ask BIOS to do this in the future, but we have a lot of existing
versions of BIOS out there that don't do this and require this support.

Thanks,
Tom

>