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Message-ID: <57e68a47-42fb-4029-a46a-c81d1522f7ff@intel.com>
Date: Thu, 7 Mar 2024 13:50:00 +1300
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Subject: Re: [PATCH 14/16] KVM: x86/mmu: Set kvm_page_fault.hva to
 KVM_HVA_ERR_BAD for "no slot" faults
Content-Language: en-US
To: Sean Christopherson <seanjc@google.com>, Paolo Bonzini
	<pbonzini@redhat.com>
CC: <kvm@vger.kernel.org>, <linux-kernel@vger.kernel.org>, Yan Zhao
	<yan.y.zhao@intel.com>, Isaku Yamahata <isaku.yamahata@intel.com>, "Michael
 Roth" <michael.roth@amd.com>, Yu Zhang <yu.c.zhang@linux.intel.com>, Chao
 Peng <chao.p.peng@linux.intel.com>, Fuad Tabba <tabba@google.com>, David
 Matlack <dmatlack@google.com>
References: <20240228024147.41573-1-seanjc@google.com>
 <20240228024147.41573-15-seanjc@google.com>
From: "Huang, Kai" <kai.huang@intel.com>
In-Reply-To: <20240228024147.41573-15-seanjc@google.com>
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On 28/02/2024 3:41 pm, Sean Christopherson wrote:
> 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>
> ---
>   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 4dee0999a66e..43f24a74571a 100644
> --- a/arch/x86/kvm/mmu/mmu.c
> +++ b/arch/x86/kvm/mmu/mmu.c
> @@ -3325,6 +3325,7 @@ 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

Not sure why this cannot be merged to the previous one?

Anyway,

Reviewed-by: Kai Huang <kai.huang@intel.com>