$qemu-kvm? -usb -monitor stdio
(qemu) device_add usb-host,vendorid=0x03f0,productid=0x134a,id=usb0 #增加usb設備
(qemu) device_del usb0 ?#刪除對應id的usb設備
2. 采用virsh管理：
virsh qemu-monitor-command --hmp testwin7 'device_del usb-host,vendorid=0x03f0,productid=0x134a,? id=usbxx0'
刪除：?virsh qemu-monitor-command testwin7 --hmp "device_del usbx"
查詢：?virsh qemu-monitor-command testwin7 --hmp "info usb"