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Subject: Re: [PATCH 1/3] KVM: x86: remove bogus #GP injection
To:     Paolo Bonzini <pbonzini@redhat.com>, linux-kernel@vger.kernel.org,
        kvm@vger.kernel.org
Cc:     Sean Christopherson <sean.j.christopherson@intel.com>,
        Alexander Graf <graf@amazon.com>
References: <20201214183250.1034541-1-pbonzini@redhat.com>
 <20201214183250.1034541-2-pbonzini@redhat.com>
From:   Tom Lendacky <thomas.lendacky@amd.com>
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Date:   Mon, 14 Dec 2020 14:50:44 -0600
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On 12/14/20 12:32 PM, Paolo Bonzini wrote:
> There is no need to inject a #GP from kvm_mtrr_set_msr, kvm_emulate_wrmsr will
> handle it.
> 
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>

> ---
>  arch/x86/kvm/mtrr.c | 6 +-----
>  1 file changed, 1 insertion(+), 5 deletions(-)
> 
> diff --git a/arch/x86/kvm/mtrr.c b/arch/x86/kvm/mtrr.c
> index 7f0059aa30e1..f472fdb6ae7e 100644
> --- a/arch/x86/kvm/mtrr.c
> +++ b/arch/x86/kvm/mtrr.c
> @@ -84,12 +84,8 @@ bool kvm_mtrr_valid(struct kvm_vcpu *vcpu, u32 msr, u64 data)
>  	} else
>  		/* MTRR mask */
>  		mask |= 0x7ff;
> -	if (data & mask) {
> -		kvm_inject_gp(vcpu, 0);
> -		return false;
> -	}
>  
> -	return true;
> +	return (data & mask) == 0;
>  }
>  EXPORT_SYMBOL_GPL(kvm_mtrr_valid);
>  
>