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Date:   Fri, 31 Mar 2023 14:59:18 +0800
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Subject: Re: [PATCH v13 016/113] KVM: TDX: x86: Add ioctl to get TDX
 systemwide parameters
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To:     Zhi Wang <zhi.wang.linux@gmail.com>, isaku.yamahata@intel.com
Cc:     kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
        isaku.yamahata@gmail.com, Paolo Bonzini <pbonzini@redhat.com>,
        erdemaktas@google.com, Sean Christopherson <seanjc@google.com>,
        Sagi Shahar <sagis@google.com>,
        David Matlack <dmatlack@google.com>,
        Kai Huang <kai.huang@intel.com>,
        Sean Christopherson <sean.j.christopherson@intel.com>
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 <20230325104306.00004585@gmail.com>
From:   Xiaoyao Li <xiaoyao.li@intel.com>
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On 3/25/2023 4:43 PM, Zhi Wang wrote:
> On Sun, 12 Mar 2023 10:55:40 -0700
> isaku.yamahata@intel.com  wrote:
> 
> Does this have to be a new generic ioctl with a dedicated new x86_ops? SNP
> does not use it at all and all the system-scoped ioctl of SNP going through
> the CCP driver. So getting system-scope information of TDX/SNP will end up
> differently.
> 
> Any thought, Sean? Moving getting SNP system-wide information to
> KVM dev ioctl seems not ideal and TDX does not have a dedicated driver like
> CCP. Maybe make this ioctl TDX-specific? KVM_TDX_DEV_OP?

What's the real different of it? For me, it's just renaming 
KVM_MEMORY_ENCRYPT_OP to KVM_TDX_DEV_OP and maybe add some error message 
if the IOCTL is issued for AMD plaform.