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Date:   Wed, 6 Jul 2022 15:27:39 -0700
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Subject: Re: [PATCH v8 1/5] x86/tdx: Add TDX Guest attestation interface
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To:     Kai Huang <kai.huang@intel.com>,
        Dave Hansen <dave.hansen@intel.com>,
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From:   Sathyanarayanan Kuppuswamy 
        <sathyanarayanan.kuppuswamy@linux.intel.com>
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On 7/5/22 3:31 PM, Kai Huang wrote:
> On Tue, 2022-07-05 at 14:21 -0700, Sathyanarayanan Kuppuswamy wrote:
>> SGX is a related feature. It also uses IOCTL approach for enclave provisioning.
>>
>> arch/x86/kernel/cpu/sgx/ioctl.c
> 
> SGX isn't a good example here.  The IOCTLs are used to create enclaves, but not
> for attestation.  SGX attestation relies on enclave itself to get/verify the
> report, etc, so has no interaction with the kernel.

If you are looking for an attestation specific example, you can only check the AMD
code.

https://patchwork.kernel.org/project/linux-mm/patch/20220307213356.2797205-44-brijesh.singh@amd.com/

Also, sev_get_attestation_report() in arch/x86/kvm/svm/sev.c also implements attestation
IOCTL specific to KVM.

-- 
Sathyanarayanan Kuppuswamy
Linux Kernel Developer