Hi, I want to create a virtual hci device on my virtual machine. I have seen that qemu has options supporting this https://qemu.weilnetz.de/doc/qemu-doc.html#Bluetooth_0028R_0029-options and https://qemu.weilnetz.de/doc/qemu-doc.html#pcsys_005fusb Is there any support for these options in libvirt? I was not able to find anything in documentation so I added the qemu command line xml as follows <qemu:commandline> <qemu:arg value='-usbdevice'/> <qemu:arg value='bt:hci'/> <qemu:arg value='-bt'/> <qemu:arg value='hci,host'/> </qemu:commandline> but when I try to run my machine from virt-manager i get the following error: Error starting domain: internal error: process exited while connecting to monitor: 2017-02-28T21:25:51.735987Z qemu-system-x86_64: -device ich9-usb-ehci1,id=usb,bus=pcie.0,addr=0x1d.0x7: PCI: slot 29 function 7 not available for ich9-usb-ehci1, in use by ich9-usb-ehci1 this error does not appear if I remove the commandline xml nodes Does anyone have any guidance for troubleshooting this? If it helps at all, virsh -v gives 2.1.0, virt-manager about page lists 1.3.2 and qemu-system-x86_64 --help gives 2.6.1 I am running Ubuntu 16.10. thanks, Max Ehrlich