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Date:   Fri, 4 Mar 2022 16:43:11 +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,
        thomas.lendacky@amd.com, brijesh.singh@amd.com, x86@kernel.org,
        linux-kernel@vger.kernel.org,
        Dave Hansen <dave.hansen@linux.intel.com>
Subject: Re: [PATCHv5 01/30] x86/tdx: Detect running as a TDX guest in early
 boot
Message-ID: <YiIzgg3Ql81He0X9@nazgul.tnic>
References: <20220302142806.51844-1-kirill.shutemov@linux.intel.com>
 <20220302142806.51844-2-kirill.shutemov@linux.intel.com>
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On Wed, Mar 02, 2022 at 05:27:37PM +0300, Kirill A. Shutemov wrote:
> +void __init tdx_early_init(void)
> +{
> +	u32 eax, sig[3];
> +
> +	cpuid_count(TDX_CPUID_LEAF_ID, 0, &eax, &sig[0], &sig[2],  &sig[1]);
> +
> +	BUILD_BUG_ON(sizeof(sig) != sizeof(TDX_IDENT) - 1);

That's new.

Is that pure paranoia or what are you protecting here against?

-- 
Regards/Gruss,
    Boris.

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