[   37.274815] unregister_netdevice: waiting for ktst-veth to become free. Usage count = 16
[   37.274953] unregister_netdevice: waiting for lo to become free. Usage count = 4
[   37.275004] unregister_netdevice: waiting for ktst-veth to become free. Usage count = 18
[   37.275054] unregister_netdevice: waiting for lo to become free. Usage count = 6