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Date:   Tue, 28 Sep 2021 15:18:46 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Joerg Roedel <joro@8bytes.org>
Cc:     "Kuppuswamy, Sathyanarayanan" 
        <sathyanarayanan.kuppuswamy@linux.intel.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, x86@kernel.org,
        Paolo Bonzini <pbonzini@redhat.com>,
        Juergen Gross <jgross@suse.com>, Deep Shah <sdeep@vmware.com>,
        VMware Inc <pv-drivers@vmware.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Peter H Anvin <hpa@zytor.com>,
        Dave Hansen <dave.hansen@intel.com>,
        Tony Luck <tony.luck@intel.com>,
        Dan Williams <dan.j.williams@intel.com>,
        Andi Kleen <ak@linux.intel.com>,
        Kirill Shutemov <kirill.shutemov@linux.intel.com>,
        Sean Christopherson <seanjc@google.com>,
        Kuppuswamy Sathyanarayanan <knsathya@kernel.org>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v6 04/11] x86/tdx: Add protected guest support for TDX
 guest
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References: <20210903172812.1097643-1-sathyanarayanan.kuppuswamy@linux.intel.com>
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On Tue, Sep 28, 2021 at 03:04:36PM +0200, Joerg Roedel wrote:
> Yes, but distributions will enable this in their default configs, so the
> function call will happen on every Intel machine, even on bare-metal.

The result of whether the guest is a TDX needs to be cached and queried
instead anyway:

https://lkml.kernel.org/r/YVL4ZUGhfsh1QfRX@zn.tnic

-- 
Regards/Gruss,
    Boris.

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