followup: my understanding is there are a bunch of usb interfaces:
uhci is usb 1.0 ehci is usb 2.0 xhci is usb 3.0 … -device piix3-usb-uhci will create an usb 1.0 interface. I guess usb 1.0 is insufficent for modern usb devices so windows errors with code 10. ehci have enough to bring full support for modern usb devices. qemu is like LEGO where you can wire it all together :-) refference: https://github.com/qemu/qemu/blob/master/docs/usb2.txt https://en.wikipedia.org/wiki/Host_controller_interface_(USB,_Firewire)#USB -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/685096 Title: USB Passthrough not working for Windows 7 guest Status in QEMU: Confirmed Status in “qemu-kvm” package in Ubuntu: Confirmed Bug description: USB Passthrough from host to guest is not working for a 32-bit Windows 7 guest, while it works perfectly for a 32-bit Windows XP guest. The device appears in the device manager of Windows 7, but with "Error code 10: device cannot start". I have tried this with numerous USB thumbdrives and a USB wireless NIC, all with the same result. The device name and functionality is recognized, so at least some USB negotiation is taking place. I am trying this with the latest git-pull of QEMU-KVM. The command line to launch qemu-kvm for win7 is: sudo /home/user/local_install/bin/qemu-system-x86_64 -cpu core2duo -m 1024 -smp 2 -vga std -hda ./disk_images/win7.qcow -vnc :1 -boot c -usb -usbdevice tablet -usbdevice host:0781:5150 The command line to launch qemu-kvm for winxp is: sudo /home/user/local_install/bin/qemu-system-x86_64 -cpu core2duo -m 1024 -smp 2 -usb -vga std -hda ./winxpsp3.qcow -vnc :0 -boot c -usbdevice tablet -usbdevice host:0781:5150 Any help is appreciated. To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/685096/+subscriptions
