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Date:   Sun, 15 Aug 2021 16:39:09 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Tom Lendacky <thomas.lendacky@amd.com>
Cc:     linux-kernel@vger.kernel.org, x86@kernel.org,
        linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org,
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        Brijesh Singh <brijesh.singh@amd.com>,
        Joerg Roedel <joro@8bytes.org>,
        Andi Kleen <ak@linux.intel.com>,
        Sathyanarayanan Kuppuswamy 
        <sathyanarayanan.kuppuswamy@linux.intel.com>,
        Tianyu Lan <Tianyu.Lan@microsoft.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Andy Lutomirski <luto@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Joerg Roedel <jroedel@suse.de>
Subject: Re: [PATCH v2 03/12] x86/sev: Add an x86 version of prot_guest_has()
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On Sun, Aug 15, 2021 at 08:53:31AM -0500, Tom Lendacky wrote:
> It's not a cross-vendor thing as opposed to a KVM or other hypervisor
> thing where the family doesn't have to be reported as AMD or HYGON.

What would be the use case? A HV starts a guest which is supposed to be
encrypted using the AMD's confidential guest technology but the HV tells
the guest that it is not running on an AMD SVM HV but something else?

Is that even an actual use case?

Or am I way off?

I know we have talked about this in the past but this still sounds
insane.

-- 
Regards/Gruss,
    Boris.

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