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Subject: Re: [PATCH v2 21/66] KVM: x86: Use supported_xcr0 to detect MPX
 support
To:     Sean Christopherson <sean.j.christopherson@intel.com>
Cc:     Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Joerg Roedel <joro@8bytes.org>, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org, Xiaoyao Li <xiaoyao.li@intel.com>
References: <20200302235709.27467-1-sean.j.christopherson@intel.com>
 <20200302235709.27467-22-sean.j.christopherson@intel.com>
From:   Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <c2faf73b-56e4-a398-430d-ad6f0afed6e4@redhat.com>
Date:   Tue, 3 Mar 2020 15:34:08 +0100
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On 03/03/20 00:56, Sean Christopherson wrote:
>  
>  bool kvm_mpx_supported(void)
>  {
> -	return ((host_xcr0 & (XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR))
> -		 && kvm_x86_ops->mpx_supported());
> +	return supported_xcr0 & (XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR);
>  }

Better check that both bits are set.

Paolo