Message-ID: <f67229d5-c92e-5953-5f77-1dee2c7643b3@redhat.com>
Date:   Fri, 24 Dec 2021 10:16:16 +0100
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Subject: Re: [PATCH 03/26] x86/tdx: Add __tdx_module_call() and
 __tdx_hypercall() helper functions
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To:     "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        Borislav Petkov <bp@alien8.de>
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,
        sdeep@vmware.com, seanjc@google.com, tony.luck@intel.com,
        vkuznets@redhat.com, wanpengli@tencent.com, x86@kernel.org,
        linux-kernel@vger.kernel.org
References: <20211214150304.62613-1-kirill.shutemov@linux.intel.com>
 <20211214150304.62613-4-kirill.shutemov@linux.intel.com>
 <YcIm8fngUsVulUoI@zn.tnic>
 <20211223165548.xr57h25g4diixivp@black.fi.intel.com>
From:   Paolo Bonzini <pbonzini@redhat.com>
In-Reply-To: <20211223165548.xr57h25g4diixivp@black.fi.intel.com>
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On 12/23/21 17:55, Kirill A. Shutemov wrote:
> 	In a TDX based VM, since the VMM is an untrusted entity, an intermediary
> 	layer -- TDX module -- facilitates secure communication between the host
> 	and the guest. TDX module is loaded like a firmware into a special CPU
> 	mode called SEAM. TDX guests communicate with the TDX module using the
> 	TDCALL instruction.
> 
> Does it look fine?

Looks good but I wouldn't say "like a firmware".  The TDX module is the 
"real" hypervisor, it's not firmware.

Paolo