Re: [PATCH v4 05/15] x86/sev: Use kernel provided SVSM Calling Areas

From: Borislav Petkov
Date: Fri May 17 2024 - 15:24:22 EST


On Wed, May 08, 2024 at 03:09:02PM -0500, Tom Lendacky wrote:
> If we're not running at VMPL0 (based on the RMPADJUST check) and if the SVSM
> doesn't advertise a non-zero VMPL value, we will self-terminate. So those
> values are only set if we are not running at VMPL0 and the SVSM has provided
> a non-zero value to us.
>
> I'm going to turn the function into a bool function so that the call
> becomes:
>
> if (!svsm_setup_caa(cc_info))
> return;

Sure, I guess I'm misled by the

if (bla)
sev_es_terminate()

which is a function call but I need to read its name to realize that
after that point we're either terminated or we have all the stuff
required to run on a SVSM.

> I do. I think you're missing the RMPADJUST check that causes the function to
> return early if we're running at VMPL0.

Yap.

--
Regards/Gruss,
Boris.

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