[Qemu-devel] Re: KVM call agenda for Jan 26

[Anthony Liguori <anthony@codemonkey.ws>]

On 01/26/2010 08:26 AM, Avi Kivity wrote:
> On 01/26/2010 04:22 PM, Anthony Liguori wrote:
>> On 01/26/2010 08:15 AM, Avi Kivity wrote:
>>> On 01/26/2010 04:13 PM, Anthony Liguori wrote:
>>>>> Me too, especially as the whole stack is involved, and qemu is the 
>>>>> topmost part from our perspective (no doubt libvirt will want to 
>>>>> integrate that functionality as well).
>>>>
>>>>
>>>> I'm not sure I agree.  It would use no code from qemu and really 
>>>> benefit in no way from being part of qemu.  I don't feel that 
>>>> strongly about it though.
>>>>
>>>
>>> It would need to know which cpuid bits qemu supports.  Only qemu 
>>> knows that.
>>
>> I'm not sure I understand why.  Can you elaborate?
>>
>
> If qemu doesn't recognize -cpu qemu64,+nx, then no amount of hardware 
> and kvm.ko support will allow the user to enable nx in a guest.

Does -cpu host filter out flags that we don't know about?  I'm pretty 
sure it doesn't.  Since we're planning on moving to -cpu host by default 
for KVM, does it really matter?

Oh, I was under the impression that the tool was meant to be software 
agnostic.  IOW, here are all the virt features your hardware supports.

Regards,

Anthony Liguori