Re: [Qemu-devel] USB Passthrough not working for Windows 7 guest

[Jens Frederich]

>On 2013-11-05 17:01, Frederich, Jens wrote:
>> Hi all,
>>
>> we're currently evaluating different RTOS systems (Windows CE, Intime, RTX,
>> etc.).
>> One system is Linux RT + KVM/QEMU with a Windows 7 guest. Up to now all
>> works fine, Linux RT has good latency and KVM/Qemu setup was easy. But one
>> QEMU bug
>> breaks my measurement setup and evaluation.
>>
>> I've some usb devices for the Windows 7 guest. I configure them as USB
>> passthrough.
>> The devices appears in the device manager of Windows 7, but with
>> "Error code 10": device cannot start". The Windows driver fails on USB set
>> configuration.
>> The driver creates a IRP and send it via IOCTRL to lower layer. The IOCTRL
>> fails with
>> invalid parameter.
>>
>> driver log:
>> 00000009      0.65470564      vnCDrvUsbControlRequestSetConfiguration,
>> WdfUsbTargetDeviceSelectConfig single interface failed 0xc000000d
>> 00000010      0.65472370      vnCDrvUsbIFPrepareHardwareState,
>> vnCDrvUsbControlRequestSetConfiguration failed: 0xc000000d
>> 00000011      0.65473646      vnCDrvDevConPrepareHardware,
>> vnCDrvUsbIFPrepareHardwareState failed 0xc000000d
>> 00000012      0.65474838      vnCDrvEvtDevicePrepareHardware,
>> vnCDrvDevConPrepareHardware failed 0xc0000001
>> 00000013      0.6547
>>
>> This bug breaks my latency measurement setup and Linux RT is out of the
>> evaluationg
>> race. Windows CE should not win :-), it there anyway workaround or hack to
>> fix the issue?
>
>Workaround: Pass-through one of the (typically) many USB host
>controllers to the Windows guest (vfio or classic pci-assign). I did
>this back then when *HCI emulation was still pretty immature.
>
>But USB device pass-through should also work. Do you happen to pass a
>USB 2.0 device via an emulated UHCI? Or are you already using the EHCI
>emulation?

I'm not sure which mode it has been. I've used the virt-manager to configure
the device. A usb controller is already configured in mode 'default'.
My steps on virt-manager:

1. add hardware
2. select usb host device
3. I can see my usb device, I select it
4. start guest and open Windows device manager

I don't know is this UHCI or EHCI? On the usb host device list are
some controller listed e.q. xhci, ehci and so on. Should I map these
controller to Windows 7 as well?

thanks,
Jens