Re: [RFC Part1 PATCH 07/13] x86/compressed: register GHCB memory when SNP is active

Borislav Petkov
2021-04-08T08:17:43Z

On Wed, Apr 07, 2021 at 12:34:59PM -0500, Brijesh Singh wrote:
> The feature is part of the GHCB version 2 and is enforced by the
> hypervisor. I guess it can be extended for the ES. Since this feature
> was not available in GHCB version 1 (base ES) so it should be presented
> as an optional for the ES ?

Yeah, it probably is not worth the effort. If an attacker controls the
guest kernel, then it can re-register a new GHCB so it doesn't really
matter.

--
Regards/Gruss,
Boris.