On 21 May 2013 11:01, Daniel P. Berrange <berrange@redhat.com> wrote:
On Tue, May 21, 2013 at 07:55:27PM +1000, Paul Mackerras wrote:
I think libvirt needs some more sensible way to ask qemu what its capabilities are. Currently it has no way to ask qemu "what machines can you emulate with kvm acceleration?" If the user has asked for a KVM domain then the default machine should be one that can be provided by KVM. At present it isn't, on PowerPC.
If QEMU can provide more intelligent info in this respect, then libvirt can use it.
I think this would make sense. Currently for ARM to get KVM acceleration you have to use a specific guest CPU (A15), and so you have to use a machine which supports that CPU (currently just vexpress-a15). But we don't expose any way for libvirt to tell that it needs an A15 or which machine models support which CPUs. In fact we don't even give a sensible error message if you try to use a wrong CPU, we'll just blithely push ahead and behave very weirdly. thanks -- PMM