What were you trying to do that didn't work?

Boot a VM after updating values of its interface. Unfortunately I accidentally set the wrong model type.

What is the impact of this issue to you?

Not big of an impact. I can just fix the problem based on the error message.

Please provide the package NVR for which the bug is seen:

libvirt-10.10.0-1.el9

How reproducible is this bug?:

100%

Steps to reproduce

1.  Update the interface device with an invalid model type for the persistent configuration, e.g.

   # cat iface.xml
   ...
      <model type="madremia"/>
   ...
   # virsh update-device vm iface.xml --config
   Device updated successfully
   # virsh start vm
   error: internal error: QEMU unexpectedly closed the monitor (vm='avocado-vt-vm1'): 2024-12-24T08:34:08.956689Z qemu-kvm: -device {"driver":"madremia","netdev":"hostnet0","id":"net0","mac":"52:54:00:af:a7:3b","devno":"fe.0.0001"}: 'madremia' is not a valid device model name
   

Expected results

The behavior should be the same as for updating on a running machine:

# virsh update-device avocado-vt-vm1 iface.xml --live
error: Failed to update device from iface.xml
error: Operation not supported: cannot modify network device model from virtio to madremia

Actual results

The device is updated with the invalid value.