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Subject: Re: [PATCH v8 4/4] kvm: vmx: virtualize split lock detection
To:     Thomas Gleixner <tglx@linutronix.de>,
        Paolo Bonzini <pbonzini@redhat.com>, kvm@vger.kernel.org,
        Sean Christopherson <sean.j.christopherson@intel.com>
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        Arvind Sankar <nivedita@alum.mit.edu>
References: <20200414063129.133630-1-xiaoyao.li@intel.com>
 <20200414063129.133630-5-xiaoyao.li@intel.com>
 <87y2qwmszt.fsf@nanos.tec.linutronix.de>
From:   Xiaoyao Li <xiaoyao.li@intel.com>
Message-ID: <906dd919-3ae5-5279-b706-168e509ce953@intel.com>
Date:   Thu, 16 Apr 2020 10:12:26 +0800
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On 4/16/2020 3:47 AM, Thomas Gleixner wrote:
> Xiaoyao Li <xiaoyao.li@intel.com> writes:
> 
>> Due to the fact that TEST_CTRL MSR is per-core scope, i.e., the sibling
>> threads in the same physical CPU core share the same MSR, only
>> advertising feature split lock detection to guest when SMT is disabled
>> or unsupported, for simplicitly.
> 
> That's not for simplicity. It's for correctness because you cannot
> provide consistent state to a guest.
> 

I'll correct it.

Thanks!
-Xiaoyao