Date:   Fri, 31 Dec 2021 18:19:35 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc:     tglx@linutronix.de, mingo@redhat.com, dave.hansen@intel.com,
        luto@kernel.org, peterz@infradead.org,
        sathyanarayanan.kuppuswamy@linux.intel.com, aarcange@redhat.com,
        ak@linux.intel.com, dan.j.williams@intel.com, david@redhat.com,
        hpa@zytor.com, jgross@suse.com, jmattson@google.com,
        joro@8bytes.org, jpoimboe@redhat.com, knsathya@kernel.org,
        pbonzini@redhat.com, sdeep@vmware.com, seanjc@google.com,
        tony.luck@intel.com, vkuznets@redhat.com, wanpengli@tencent.com,
        x86@kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 07/26] x86/tdx: Handle CPUID via #VE
Message-ID: <Yc87mpjSNbgUtqKV@zn.tnic>
References: <20211214150304.62613-1-kirill.shutemov@linux.intel.com>
 <20211214150304.62613-8-kirill.shutemov@linux.intel.com>
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In-Reply-To: <20211214150304.62613-8-kirill.shutemov@linux.intel.com>
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On Tue, Dec 14, 2021 at 06:02:45PM +0300, Kirill A. Shutemov wrote:
> In TDX guests, most CPUID leaf/sub-leaf combinations are virtualized
> by the TDX module while some trigger #VE.
> 
> Implement the #VE handling for EXIT_REASON_CPUID by handing it through
> the hypercall, which in turn lets the TDX module handle it by invoking
> the host VMM.
> 
> More details on CPUID Virtualization can be found in the TDX module
> specification [1], the section titled "CPUID Virtualization".

The exact name and section should be enough to find the spec document
because...

> 
> [1] - https://software.intel.com/content/dam/develop/external/us/en/documents/tdx-module-1.0-public-spec-v0.931.pdf

... those links are never stable and become stale eventually. Just save
yourself the effort of adding them to commit messages.

-- 
Regards/Gruss,
    Boris.

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