Re: [RFC Part1 PATCH 06/13] x86/compressed: rescinds and validate the memory used for the GHCB

From: Borislav Petkov
Date: Wed Apr 07 2021 - 07:25:56 EST


On Tue, Apr 06, 2021 at 02:42:43PM -0500, Tom Lendacky wrote:
> The GHCB spec only defines the "0" reason code set. We could provide Linux
> it's own reason code set with some more specific reason codes for
> failures, if that is needed.

Why Linux only?

Don't we want to have a generalized set of error codes which say what
has happened so that people can debug?

Let's take the above case Brijesh explains: guest tries a page state
change, HV cannot manage for whatever reason and guest terminates with a
"general request".

Wouldn't you want to at least have a *hint* as to why the guest
terminated instead of just "guest terminated"?

I.e., none of those:

https://duckduckgo.com/?q=dumb+error+messages&iax=images&ia=images

:-)

--
Regards/Gruss,
Boris.

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