Comment 9 for bug 1996176

Same problem on Kinetic (as expected) before the update:
   1073 root 20 0 1659848 47424 33744 R 93.8 0.1 0:20.74 libvirtd

Upgrading was just fine (again there was so much in flight that I won't copy all of it).
But an excerpt:
...
Setting up python3-software-properties (0.99.27.1) ...
Setting up linux-headers-5.19.0-27-generic (5.19.0-27.28) ...
Setting up libvirt-daemon-driver-qemu (8.6.0-0ubuntu3.1) ...
Setting up libvirt-daemon (8.6.0-0ubuntu3.1) ...
Setting up libvirt-daemon-driver-storage-rbd (8.6.0-0ubuntu3.1) ...
Setting up qemu-system-gui (1:7.0+dfsg-7ubuntu2.1) ...
Setting up libqmi-glib5:amd64 (1.32.0-1ubuntu0.22.10.1) ...
Setting up linux-headers-generic (5.19.0.27.24) ...
Setting up software-properties-common (0.99.27.1) ...
Setting up libvirt-daemon-system (8.6.0-0ubuntu3.1) ...
Installing new version of config file /etc/apparmor.d/abstractions/libvirt-qemu ...
virtlockd.service is a disabled or a static unit, not starting it.
Setting up libvirt-daemon dnsmasq configuration.
...

BTW even correctly spotting this due to a lib update :-)
...
VM guests are running outdated hypervisor (qemu) binaries on this host:
 'j' with pid 1711

On trigger and libvirt interaction it says down in regard to cpu usage:
   4589 root 20 0 1659824 44516 33428 S 0.3 0.1 0:00.96 libvirtd