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Date:   Sun, 6 Feb 2022 20:50:28 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     Brijesh Singh <brijesh.singh@amd.com>
Cc:     x86@kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
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        Michael Roth <michael.roth@amd.com>,
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        "Kirill A . Shutemov" <kirill@shutemov.name>,
        Andi Kleen <ak@linux.intel.com>,
        "Dr . David Alan Gilbert" <dgilbert@redhat.com>,
        brijesh.ksingh@gmail.com, tony.luck@intel.com, marcorr@google.com,
        sathyanarayanan.kuppuswamy@linux.intel.com
Subject: Re: [PATCH v9 38/43] x86/sev: Use firmware-validated CPUID for
 SEV-SNP guests
Message-ID: <YgAmhHv+kVtkIUB8@zn.tnic>
References: <20220128171804.569796-1-brijesh.singh@amd.com>
 <20220128171804.569796-39-brijesh.singh@amd.com>
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On Fri, Jan 28, 2022 at 11:17:59AM -0600, Brijesh Singh wrote:
> +/*
> + * It is useful from an auditing/testing perspective to provide an easy way
> + * for the guest owner to know that the CPUID table has been initialized as
> + * expected, but that initialization happens too early in boot to print any
> + * sort of indicator, and there's not really any other good place to do it.

If you really wanna do it - and I think it might make sense to be able
to dump that table for debugging or whatever purposes, you could define
a cmdline parameter like

	sev=debug

or so, which would enable checking and dumping of the cpuid table.

For example...

-- 
Regards/Gruss,
    Boris.

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