Am 23.06.2015 um 18:25 schrieb Daniel P. Berrange: > 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.
This coupling is by design and we expect all KVM/QEMU users to adhere to it, including those that use the libvirt tool (which I assume is going to be the majority of KVM users). Either you want a certain backwards-compatible machine and CPU, or you want the latest and greatest - why in the world mix and match?! Would a qemu64-2.3 model help here that pc*-2.3 could use? I believe that's been proposed in the past. I don't oppose the idea of a fully-custom CPU, but this blatant attempt of ignoring QEMU's CPU versioning by libvirt worries me. Regards, Andreas -- SUSE Linux GmbH, Maxfeldstr. 5, 90409 Nürnberg, Germany GF: Felix Imendörffer, Jane Smithard, Dilip Upmanyu, Graham Norton; HRB 21284 (AG Nürnberg)
