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Date:   Tue, 15 Feb 2022 13:54:48 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     "Kirill A. Shutemov" <kirill@shutemov.name>
Cc:     Brijesh Singh <brijesh.singh@amd.com>, x86@kernel.org,
        linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
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        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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        sathyanarayanan.kuppuswamy@linux.intel.com
Subject: Re: [PATCH v10 21/45] x86/mm: Add support to validate memory when
 changing C-bit
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On Tue, Feb 15, 2022 at 03:43:31PM +0300, Kirill A. Shutemov wrote:
> I don't think it works. TDX and SME/SEV has opposite polarity of the mask.
> SME/SEV has to clear the mask to share the page. TDX has to set it.
> 
> Making a single global mask only increases confusion.

Didn't you read the rest of the thread with Tom's suggestion? I think
there's a merit in having a cc_vendor or so which explicitly states what
type of HV the kernel runs on...

-- 
Regards/Gruss,
    Boris.

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