Re: [PATCH] kvm-vmx: add module parameter to avoid trapping HLT instructions (v2)

Anthony Liguori
2010-12-06T14:08:11Z

On 12/06/2010 08:02 AM, Avi Kivity wrote:
> On 12/06/2010 04:01 PM, Avi Kivity wrote:
>>> It's not just possible, it appears to be exactly what happens.
>>>
>>> I guess it makes sense that RIP gets advanced before HLT begins to
>>> wait.
>>>
>>
>>
>> It does. Good, it simplifies the patch.
>>
>
> btw, this is how kvm emulates HLT - first we advance rip, then we
> sleep the vcpu.

Yes, I assume the hardware updates RIP immediately after fetching the
instruction. That's at least how some simpler architectures I'm aware
of work.

Regards,

Anthony Liguori