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Message-ID: <6d0f2392-bc93-445d-9169-65221fb55329@intel.com>
Date: Tue, 12 Mar 2024 14:35:41 +1300
User-Agent: Mozilla Thunderbird
Subject: Re: [PATCH 07/21] KVM: VMX: Introduce test mode related to EPT
 violation VE
Content-Language: en-US
To: Paolo Bonzini <pbonzini@redhat.com>, <linux-kernel@vger.kernel.org>,
	<kvm@vger.kernel.org>
CC: <seanjc@google.com>, <michael.roth@amd.com>, <isaku.yamahata@intel.com>,
	<thomas.lendacky@amd.com>
References: <20240227232100.478238-1-pbonzini@redhat.com>
 <20240227232100.478238-8-pbonzini@redhat.com>
From: "Huang, Kai" <kai.huang@intel.com>
In-Reply-To: <20240227232100.478238-8-pbonzini@redhat.com>
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On 28/02/2024 12:20 pm, Paolo Bonzini wrote:
> From: Isaku Yamahata <isaku.yamahata@intel.com>
> 
> To support TDX, KVM is enhanced to operate with #VE.  For TDX, KVM uses the
> suppress #VE bit in EPT entries selectively, in order to be able to trap
> non-present conditions.  However, #VE isn't used for VMX and it's a bug
> if it happens.  To be defensive and test that VMX case isn't broken
> introduce an option ept_violation_ve_test and when it's set, BUG the vm.

I am wondering from HW's point of view, is it OK for the kernel to 
explicitly send #VE IPI, in which case, IIUC, the guest can legally get 
the #VE w/o being a TDX guest?