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Date:   Mon, 23 Aug 2021 06:50:06 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Michael Roth <michael.roth@amd.com>
Cc:     Brijesh Singh <brijesh.singh@amd.com>, x86@kernel.org,
        linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
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        Ingo Molnar <mingo@redhat.com>, Joerg Roedel <jroedel@suse.de>,
        Tom Lendacky <thomas.lendacky@amd.com>,
        "H. Peter Anvin" <hpa@zytor.com>, Ard Biesheuvel <ardb@kernel.org>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Sean Christopherson <seanjc@google.com>,
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        Dov Murik <dovmurik@linux.ibm.com>,
        Tobin Feldman-Fitzthum <tobin@ibm.com>,
        Vlastimil Babka <vbabka@suse.cz>, tony.luck@intel.com,
        brijesh.ksingh@gmail.com
Subject: Re: [PATCH Part1 RFC v4 22/36] x86/sev: move MSR-based VMGEXITs for
 CPUID to helper
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References: <20210707181506.30489-1-brijesh.singh@amd.com>
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On Thu, Aug 19, 2021 at 10:29:08PM -0500, Michael Roth wrote:
> The select cases where we still fetch CPUID values from hypervisor in
> SNP need careful consideration, so for the purposes of auditing the code
> for security, or just noticing things in patches, I think it's important
> to make it clear what is the "normal" SNP case (not trusting hypervisor
> CPUID values) and what are exceptional cases (getting select values from
> hypervisor). If something got added in the future, I think something
> like:
> 
>   +sev_cpuid_hv(0x8000001f, ...)
> 
> would be more likely to raise eyebrows and get more scrutiny than:
> 
>   +sev_cpuid(0x8000001f, ...)
> 
> where it might get lost in the noise or mistaken as similar to
> sev_snp_cpuid().
> 
> Maybe a bit contrived, and probably not a big deal in practice, but
> conveying the source it in the naming does seem at least seem slightly
> better than not doing so.

Ok, makes sense.

Thx.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette