[libvirt] [BUG] We can hot plug more than one vhost-user nics with the same chardev backend

We use virsh attach-device to hot-plug vhost-user nic with the following xml: <interface type='vhostuser'> <mac address='52:54:01:3b:83:a5'/> <source type='unix' path='/var/run/vhost-user/port1' mode='client'/> <target dev='port1'/> <model type='virtio'/> <driver queues='4'/> </interface> We can successfully hot plug more than one vhost-user nics with the same unix path ('/var/run/vhost-user/port1') which is a chardev backend. However, only one nic attached can work, because the unix path can only pair with one front-end of nic. So should we do something to forbid this operation?