From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@redhat.com>
Subject: Re: [Patch v3] Enable CPU SMEP feature for KVM
Date: Sun, 29 May 2011 10:20:47 +0300
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Cc: "Yang, Wei Y" <wei.y.yang@intel.com>,
	"kvm@vger.kernel.org" <kvm@vger.kernel.org>
To: "Li, Xin" <xin.li@intel.com>
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On 05/29/2011 10:15 AM, Li, Xin wrote:
> >  >  >
> >  >  >   >   +		else
> >  >  >   >   +			best->ebx&= ~(bit(X86_FEATURE_SMEP));
> >  >  >
> >  >  >   Not needed - x86.c already masks unsupported features.
> >  >
> >  >  Should KVM still support guest SMEP when host disables it thru nosmep?
> >
> >  No.  We treat nosmep as "no smep for the kernel and any guests".  NX is
> >  treated in the same way.
>
> Then we need to add logic to do_cpuid_ent to mask off leaf 7 features when host
> disables it.

Yes.

-- 
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.