From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [PATCH] KVM: x86: no need to check CPL for XSETBV on VMX
Date: Fri, 15 Apr 2016 12:43:39 +0200
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To: Yang Zhang <yang.zhang.wz@gmail.com>,
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On 15/04/2016 12:37, Yang Zhang wrote:
>> I don't think this is performance-sensitive, hence it's simpler to keep
>> the code as simple as possible.  For example, if one added XSETBV
>> support to the emulator, your patch would introduce a bug.
> 
> In what case we need to decode XSETBV?

The emulator can be a way to unify code between vmx and svm.  It is an
alternative to writing small wrapper functions such as kvm_set_xcr.

Thanks,

Paolo