Am 23.06.2015 um 18:38 schrieb Eduardo Habkost: > On Tue, Jun 23, 2015 at 06:33:05PM +0200, Michael S. Tsirkin wrote: >> On Tue, Jun 23, 2015 at 05:25:55PM +0100, Daniel P. Berrange wrote: >>> Whether QEMU changed the CPU for existing machines, or only for new >>> machines is actually not the core problem. Even if we only changed >>> the CPU in new machines that would still be an unsatisfactory situation >>> because we want to be able to be able to access different versions of >>> the CPU without the machine type changing, and access different versions >>> of the machine type, without the CPU changing. IOW it is the fact that the >>> changes in CPU are tied to changes in machine type that is the core >>> problem. >> >> But that's because we are fixing bugs. If CPU X used to work on >> hardware Y in machine type A and stopped in machine type B, this is >> because we have determined that it's the right thing to do for the >> guests and the users. We don't break stuff just for fun. >> Why do you want to bring back the bugs we fixed? > > I didn't take the time to count them, but I bet most of the commits I > listed on my previous e-mail message are not bug fixes, but new > features.
Huh? Of course the latest machine model get new features. The point is that the previous ones don't and that's what we are providing them for - libvirt is expected to choose one machine and the contract with QEMU is that for that machine the CPU does *not* grow new features, and we're going at great lengths to achieve that. So this thread feels more and more weird... Regards, Andreas -- SUSE Linux GmbH, Maxfeldstr. 5, 90409 Nürnberg, Germany GF: Felix Imendörffer, Jane Smithard, Dilip Upmanyu, Graham Norton; HRB 21284 (AG Nürnberg)