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Date:   Sun, 13 Feb 2022 18:21:33 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     Tom Lendacky <thomas.lendacky@amd.com>
Cc:     Brijesh Singh <brijesh.singh@amd.com>,
        "Kirill A . Shutemov" <kirill@shutemov.name>, x86@kernel.org,
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        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Joerg Roedel <jroedel@suse.de>,
        "H. Peter Anvin" <hpa@zytor.com>, Ard Biesheuvel <ardb@kernel.org>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Sean Christopherson <seanjc@google.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Jim Mattson <jmattson@google.com>,
        Andy Lutomirski <luto@kernel.org>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Sergio Lopez <slp@redhat.com>, Peter Gonda <pgonda@google.com>,
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        Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>,
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        Dov Murik <dovmurik@linux.ibm.com>,
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        brijesh.ksingh@gmail.com, tony.luck@intel.com, marcorr@google.com,
        sathyanarayanan.kuppuswamy@linux.intel.com
Subject: Re: [PATCH v10 21/45] x86/mm: Add support to validate memory when
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On Sun, Feb 13, 2022 at 08:50:48AM -0600, Tom Lendacky wrote:
> I think there were a lot of assumptions that only SME/SEV would set
> sme_me_mask and that is used, for example, in the cc_platform_has() routine
> to figure out whether we're AMD or Intel. If you go the cc_mask route, I
> think we'll need to add a cc_vendor variable that would then be checked in
> cc_platform_has().

Right, or cc_platform_type or whatever. It would probably be a good
idea to have a variable explicitly state what the active coco flavor is
anyway, as we had some ambiguity questions in the past along the lines
of, what does cc_platform_has() need to return when running as a guest
on the respective platform.

If you have it explicitly, then it would work unambiguously simple. And
then we can get rid of CC_ATTR_GUEST_SEV_SNP or CC_ATTR_GUEST_TDX which
is clumsy.

Thx.

-- 
Regards/Gruss,
    Boris.

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