On x86 due to a compat fix host-model effectively is CUSTOM see qemuProcessUpdateGuestCPU (in coreys post).
I also checked where this gets populated but didn't find a sweet sport to see if is now different. But qemuBuildCpuModelArgStr was interesting. On 2.5 and master stripped of unimportant to aarch64 it is: - host-passthrough -> add "host" - host-model -> fail (remember x86 converts host-model to custom) - custom -> add "whatever was given" So that won't work even if we would let it pass the check. And while the code changed the semantics did not - yet there it handled host-model "like" passthrough not in the construction but due to a fallback in detection. That known I checked the qemu command strings it constructed in the past, it was: "-cpu host". Aha, no specials due to host-model (as it didn't work), so on aarch64 host-model was equal to host-passthrough with the failure that the "advertised" extra that host-model has over host-passthrough did not work. Now libvirt changed to know that and tells you that host-model is not working, but that is actually correct - even it seemed so in the first place I'd not consider this a regression in the usual sense. - Regression: sometihng that worked now fails - This: something that you thought works, but didn't now fails telling you so Summarizing in next comment to catch everybody and sync with the openstack Team on this. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1673467 Title: [ocata] unsupported configuration: CPU mode 'host-model' for aarch64 kvm domain on aarch64 host is not supported by hypervisor To manage notifications about this bug go to: https://bugs.launchpad.net/nova/+bug/1673467/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
