On 11/14/19 10:44 AM, Jiri Denemark wrote: > On s390 machines host-passthrough and host-model CPUs result in the same > guest ABI (with QEMU new enough to be able to tell us what "host" CPU is > expanded to, which was implemented around 2.9.0). So instead of using > host-passthrough CPU when there's no CPU specified in a domain XML we > can safely use host-model and benefit from CPU compatibility checks > during migration, snapshot restore and similar operations. > > > This series applies on top of "qemu: Store default CPU in domain XML" > which is already acked, but it's waiting for a QEMU patch to be applied > to 4.2.0. > > You can fetch both series at once using > > git fetch https://gitlab.com/jirkade/libvirt cpu-default-type > > Jiri Denemark (4): > cpu_conf: Fix default value for CPU match attribute > cpu_conf: Don't format empty model for host-model CPUs > cpu_s390: Don't check match attribute for host-model CPUs > qemu: Use host-model CPU on s390 by default > > src/conf/cpu_conf.c | 25 ++++---------- > src/conf/cpu_conf.h | 2 +- > src/cpu/cpu_s390.c | 18 +++++----- > src/qemu/qemu_domain.c | 33 ++++++++++++------- > .../ppc64-host+guest-compat-none.xml | 4 +-- > ...t-cpu-kvm-ccw-virtio-4.2.s390x-latest.args | 4 ++- > .../cpu-check-default-partial.xml | 4 +-- > .../cpu-host-model-features.xml | 1 - > ...lt-cpu-kvm-ccw-virtio-4.2.s390x-latest.xml | 2 +- > 9 files changed, 45 insertions(+), 48 deletions(-) > Guest defined as expected. Once I start a guest, a dumpxml showed the model name and associated features as expected. Was able to successfully migrate the guest as well. Much preferred over the old default host-passthrough way. Built libvirt using the repo and branch you provided Built QEMU using master 4.1.92 (v4.2.0-rc2-27-g65e05c82bd) - guest used machine s390-ccw-virtio-4.2 Migrated between a weird mixed environment I'm chaotically working with :) Perhaps the testing was a bit over-extensive, but it's good to make sure. Tested-by: Collin Walling <walling@xxxxxxxxxxxxx> -- Respectfully, - Collin Walling -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list
