On 24 June 2015 at 15:38, Paolo Bonzini <pbonz...@redhat.com> wrote: > It's certainly okay for libvirt and OpenStack to use the host CPU > features in order to check whether a node will run a given VM. However, > libvirt should trust that QEMU developers will not prevent a VM from > running on a previously viable host, just because you change the machine > type.
Note that this might be true for x86 but isn't (in full generality) necessarily so for other architectures like ARM. For instance if you have a host machine with a GICv3 with no v2-back-compatibility support, then you can run a VM whose machine type specifies a GICv3, but not machine types that require a GICv2... thanks -- PMM
