Subject: Re: [PATCH 5/8] KVM: SVM: fix comment
To: Paolo Bonzini <pbonzini@redhat.com>, linux-kernel@vger.kernel.org,
        kvm@vger.kernel.org
Cc: rkrcmar@redhat.com, liran.alon@oracle.com, jmattson@google.com,
        aliguori@amazon.com, thomas.lendacky@amd.com, dwmw@amazon.co.uk,
        bp@alien8.de, x86@kernel.org
References: <20180109120311.27565-1-pbonzini@redhat.com>
 <20180109120311.27565-6-pbonzini@redhat.com>
From: David Hildenbrand <david@redhat.com>
Organization: Red Hat GmbH
Message-ID: <9e1504dc-514c-8bbd-f941-f1edca5e8f50@redhat.com>
Date: Mon, 15 Jan 2018 10:53:22 +0100
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On 09.01.2018 13:03, Paolo Bonzini wrote:
> If always==true, then read/write bits are cleared from
> the MSR permission bitmap, thus passing-through the MSR.
> Fix the comment to match reality.
> 
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
>  arch/x86/kvm/svm.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
> index 55dde3896898..31ace8d7774a 100644
> --- a/arch/x86/kvm/svm.c
> +++ b/arch/x86/kvm/svm.c
> @@ -236,7 +236,7 @@ struct amd_svm_iommu_ir {
>  
>  static const struct svm_direct_access_msrs {
>  	u32 index;   /* Index of the MSR */
> -	bool always; /* True if intercept is always on */
> +	bool always; /* True if intercept is always off */
>  } direct_access_msrs[] = {
>  	{ .index = MSR_STAR,				.always = true  },
>  	{ .index = MSR_IA32_SYSENTER_CS,		.always = true  },
> 

The function set_msr_interception() is really named confusingly.

If we pass in a "1", we clear the bit, resulting in no interception.

So 1==no intercept, 0==intercept. This function would be better named
"disable_msr_interception" or sth. like that.

Reviewed-by: David Hildenbrand <david@redhat.com>

-- 

Thanks,

David / dhildenb