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Message-ID: <4f35f658-bd0a-4461-b9db-992bef0e57a9@linux.intel.com>
Date: Sun, 4 Feb 2024 16:46:35 +0800
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Subject: Re: [PATCH v18 053/121] KVM: x86/mmu: TDX: Do not enable page track
 for TD guest
To: 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,
 Yan Zhao <yan.y.zhao@intel.com>, Yuan Yao <yuan.yao@linux.intel.com>
References: <cover.1705965634.git.isaku.yamahata@intel.com>
 <ba65644eb8327600c393bc3a3dc71c49e872d29f.1705965635.git.isaku.yamahata@intel.com>
From: Binbin Wu <binbin.wu@linux.intel.com>
In-Reply-To: <ba65644eb8327600c393bc3a3dc71c49e872d29f.1705965635.git.isaku.yamahata@intel.com>
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On 1/23/2024 7:53 AM, isaku.yamahata@intel.com wrote:
> From: Yan Zhao <yan.y.zhao@intel.com>
>
> TDX does not support write protection and hence page track.
> Though !tdp_enabled and kvm_shadow_root_allocated(kvm) are always false
> for TD guest, should also return false when external write tracking is
> enabled.

Nit:
The preferred shortlog prefix format is "KVM: <topic>:", remove "TDX" from
the shortlog?
"KVM: x86/mmu: Do not enable page track for TD guest" should be OK.

Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com>

>
> Cc: Yuan Yao <yuan.yao@linux.intel.com>
> Signed-off-by: Yan Zhao <yan.y.zhao@intel.com>
> ---
>   arch/x86/kvm/mmu/page_track.c | 3 +++
>   1 file changed, 3 insertions(+)
>
> diff --git a/arch/x86/kvm/mmu/page_track.c b/arch/x86/kvm/mmu/page_track.c
> index c87da11f3a04..ce698ab213c1 100644
> --- a/arch/x86/kvm/mmu/page_track.c
> +++ b/arch/x86/kvm/mmu/page_track.c
> @@ -22,6 +22,9 @@
>   
>   bool kvm_page_track_write_tracking_enabled(struct kvm *kvm)
>   {
> +	if (kvm->arch.vm_type == KVM_X86_TDX_VM)
> +		return false;
> +
>   	return IS_ENABLED(CONFIG_KVM_EXTERNAL_WRITE_TRACKING) ||
>   	       !tdp_enabled || kvm_shadow_root_allocated(kvm);
>   }