Re: [PATCH v7 02/45] x86/sev: detect/setup SEV/SME features earlier in boot

From: Borislav Petkov
Date: Wed Nov 17 2021 - 08:11:33 EST


On Mon, Nov 15, 2021 at 02:17:15PM -0600, Michael Roth wrote:
> but in order for that to happen soon enough to make use of the CPUID
> table for all CPUID intructions, it needs to be moved to just after the first
> #VC handler is setup (where snp_cpuid_init() used to be in v6).

So, it needs to happen after the initial IDT is loaded on the BSP in
startup_64_setup_env().

So why don't you call sme_enable() right after the
startup_64_setup_env() call and add a comment above it to explain why
this call needs to happen there?

Instead of sticking that call in startup_64_setup_env() where it doesn't
belong conceptually - enabling SME doesn't really have anything to do
with setting up early environment...

Hmm.

--
Regards/Gruss,
Boris.

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