Does the "managed" attribute of the hostdev element for a USB device make a difference? The Domain XML Format docs has the following sentence for the hostdev element: If managed is omitted or "no", and for USB devices, the user is responsible to call virNodeDeviceDettach (or virsh nodedev-dettach) before starting the guest or hot-plugging the device, and virNodeDeviceReAttach (or virsh nodedev-reattach) after hot-unplug or stopping the guest. Is that still accurate? The device seems to get passed through fine to my LXC container without any dettach/reattach calls. But I'm seeing some other strange USB behaviour in the guest and just want to see if it's at all related to the managed attribute. Cheers.