I spawned "pc-i440fx-wily" (which is actually xenial in very early days due to a bug back then) guests on Bionic and Focal.
New types like Bionic and Focal all have "any_layout = true" in all slots. Which is reasonable as they all are post 2.3 where this was later introduced as new default. Defining the type to "pc-i440fx-wily" on Bionic and Focal shows the issue as reported: Bionic: dev: virtio-balloon-pci, id "balloon0" bus: virtio-bus dev: virtio-balloon-device, id "" any_layout = true Focal: dev: virtio-balloon-pci, id "balloon0" bus: virtio-bus dev: virtio-balloon-device, id "" any_layout = false As already reported the hw_compat_2_3 should disable that. But since the wily/xenial confusion was exactly that maybe something was lost there when porting to newer code. There was a change how types got handled later on which might have been the source of this. The history of the odd Wily type is in these bugs: - bug 1621042 Xenial used a wily type - bug 1829868 wily type was a hybrid of 2.4 / 2.3 types Therefore the "modern" pc_i440fx_wily_machine_options use this mix to reflect that: + pc_i440fx_2_4_machine_options(m); + m->hw_version = "2.4.0"; + pcmc->broken_reserved_end = true; + compat_props_add(m->compat_props, hw_compat_2_3, hw_compat_2_3_len); + compat_props_add(m->compat_props, pc_compat_2_3, pc_compat_2_3_len); Seems like you have found a new incarnation of this old bug (from before my time here even) to continue to haunt us *sigh*. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1902654 Title: failure to migrate virtual machines with pc-i440fx-wily type to ubuntu 20.04 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/1902654/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs