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Message-ID: <e7ad9ad5-7f55-4a89-b4fb-2b0043a93552@intel.com>
Date: Mon, 13 May 2024 14:28:54 +0800
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Subject: Re: [PATCH 15/17] KVM: x86/mmu: Set kvm_page_fault.hva to
 KVM_HVA_ERR_BAD for "no slot" faults
To: Paolo Bonzini <pbonzini@redhat.com>, linux-kernel@vger.kernel.org,
 kvm@vger.kernel.org
Cc: Sean Christopherson <seanjc@google.com>, Kai Huang <kai.huang@intel.com>
References: <20240507155817.3951344-1-pbonzini@redhat.com>
 <20240507155817.3951344-16-pbonzini@redhat.com>
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From: Xiaoyao Li <xiaoyao.li@intel.com>
In-Reply-To: <20240507155817.3951344-16-pbonzini@redhat.com>
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On 5/7/2024 11:58 PM, Paolo Bonzini wrote:
> From: Sean Christopherson <seanjc@google.com>
> 
> Explicitly set fault->hva to KVM_HVA_ERR_BAD when handling a "no slot"
> fault to ensure that KVM doesn't use a bogus virtual address, e.g. if
> there *was* a slot but it's unusable (APIC access page), or if there
> really was no slot, in which case fault->hva will be '0' (which is a
> legal address for x86).
> 
> Signed-off-by: Sean Christopherson <seanjc@google.com>
> Reviewed-by: Kai Huang <kai.huang@intel.com>
> Message-ID: <20240228024147.41573-15-seanjc@google.com>
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>

> ---
>   arch/x86/kvm/mmu/mmu.c | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
> index 7630ad8cb022..d717d60c6f19 100644
> --- a/arch/x86/kvm/mmu/mmu.c
> +++ b/arch/x86/kvm/mmu/mmu.c
> @@ -3273,6 +3273,7 @@ static int kvm_handle_noslot_fault(struct kvm_vcpu *vcpu,
>   	fault->slot = NULL;
>   	fault->pfn = KVM_PFN_NOSLOT;
>   	fault->map_writable = false;
> +	fault->hva = KVM_HVA_ERR_BAD;
>   
>   	/*
>   	 * If MMIO caching is disabled, emulate immediately without