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Date: Thu, 18 Apr 2024 15:57:11 +0800
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Subject: Re: [PATCH v19 079/130] KVM: TDX: vcpu_run: save/restore host
 state(host kernel gs)
To: Isaku Yamahata <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>, Kai Huang <kai.huang@intel.com>,
 chen.bo@intel.com, hang.yuan@intel.com, tina.zhang@intel.com,
 isaku.yamahata@linux.intel.com
References: <cover.1708933498.git.isaku.yamahata@intel.com>
 <4a766983346b2c01e943348af3c5ca6691e272f9.1708933498.git.isaku.yamahata@intel.com>
 <8132ddff-16f3-482f-b08b-a73aa8eddbbc@linux.intel.com>
 <20240412201702.GJ3039520@ls.amr.corp.intel.com>
From: Binbin Wu <binbin.wu@linux.intel.com>
In-Reply-To: <20240412201702.GJ3039520@ls.amr.corp.intel.com>
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On 4/13/2024 4:17 AM, Isaku Yamahata wrote:
>>> +void tdx_prepare_switch_to_guest(struct kvm_vcpu *vcpu)
>> Just like vmx_prepare_switch_to_host(), the input can be "struct vcpu_tdx
>> *", since vcpu is not used inside the function.
>> And the callsites just use "to_tdx(vcpu)"
>>
>>> +{
>>> +	struct vcpu_tdx *tdx = to_tdx(vcpu);
>> Then, this can be dropped.
> prepare_switch_to_guest() is used for kvm_x86_ops.prepare_switch_to_guest().
> kvm_x86_ops consistently takes struct kvm_vcpu.

Oh yes, it's not suitable for tdx_prepare_switch_to_guest().
Still, it can be for tdx_prepare_switch_to_host().