Re: [libvirt] [Qemu-devel] Modern CPU models cannot be used with libvirt

On Mon, Mar 12, 2012 at 01:04:19PM +0000, Daniel P. Berrange wrote: > On Mon, Mar 12, 2012 at 09:52:27AM -0300, Eduardo Habkost wrote: > > On Sun, Mar 11, 2012 at 09:12:58AM -0500, Anthony Liguori wrote: > > > On 03/11/2012 08:27 AM, Gleb Natapov wrote: > > > >On Sat, Mar 10, 2012 at 12:24:47PM -0600, Anthony Liguori wrote: > > > >>Let's step back here. > > > >> > > > >>Why are you writing these patches? It's probably not because you > > > >>have a desire to say -cpu Westmere when you run QEMU on your laptop. > > > >>I'd wager to say that no human has ever done that or that if they > > > >>had, they did so by accident because they read documentation and > > > >>thought they had to. > > > > No, it's because libvirt doesn't handle all the tiny small details > > involved in specifying a CPU. All libvirty knows about are a set of CPU > > flag bits, but it knows nothing about 'level', 'family', and 'xlevel', > > but we would like to allow it to expose a Westmere-like CPU to the > > guest. > > This is easily fixable in libvirt - so for the point of going discussion, > IMHO, we can assume libvirt will support level, family, xlevel, etc. > And fill in all cpuid leafs by querying /dev/kvm when needed or, if TCG is used, replicating QEMU logic? And since QEMU should be usable without libvirt the same logic should be implemented in QEMU anyway.