Re: [Qemu-devel] [PATCH 1/2] [RFC] Make vmport report the processor speed

[Alexander Graf <agraf@suse.de>]

François Revol wrote:
>>> Do we implement them yet ? grep got me some MSR_IA32_TSC in kvm.c,  
>>> so I
>>> suppose yes.
>>>       
>> That is the TSC value MSR I guess. So no, we don't implement them 
>> yet.  
>> But that sounds like a way better interface to me than the VMware  
>> backdoor ;).
>>     
>
> Maybe implementing it properly would fix running ESX without the need 
> for vmport ?
>   

I haven't seen VMware accessing the relevant MSR, so I guess no :-(.

>>> Oh, I didn't notice rdtscp, might be interesting to use instead for
>>> Haiku.
>>>       
>> Maybe using a PV clocksource is even better ...
>>     
>
> ?
>   

Xenner for example uses the KVM_CLOCK to do timings, because the guest
never really knows what time it is. There was a comment on that earlier
in this thread by Avi IIRC too. If you're running virtualized, it's
usually best to use a paravirtualized clocksource.

Alex