SPICE协议桌面，定义Guest声音驱动，以及USB重定向的libvirt.xml
<devices>
...
<sound model='ac97'/>
<controller type='usb' index='0' model='ich9-ehci1'/>
<controller type='usb' index='0' model='ich9-uhci1'>
<master startport='0'/>
</controller>
<redirdev bus='usb' type='spicevmc'/>
</devices>从命令行启动的参数命令
root@ubuntu#qemu-system-x86_64 -m 4096 -drive file=disk,if=virtio -net nic -net user -spice port=5988,disable-ticketing -enable-kvm -soundhw ac97 -device qxl-vga -smp 16,sockets=1,cores=4,threads=4 -device ich9-usb-ehci1,id=usb -device ich9-usb-uhci1,masterbus=usb.0,firstport=0,multifunction=on -chardev spicevmc,name=usbredir,id=usbredirchardev1 -device usb-redir,chardev=usbredirchardev1,id=usbredirdev1