Any way to make usb passtrough work with Windows 10 HVM?

I set up a Windows 10 HVM on my qube laptop. I was able to passthrough my GPU and redirect audio through pulseaudio so I have a nearly fully functionnal windows and I’m very happy with this. I can run games with steam, and use visual studio, everything work smoothly.

However the only thing missing is that I can’t passthrough usb devices to the HVM. When I try, using qubes interface, I get this error message : ‘QubesExecption - Device attach failed: Failed to open data vchan connection’. Any ideas how to go around that issue?

It’s the only thing missing before I get a fully functionnal windows laptop running inside of qube, so I would really love to make this work.


edit : I’m on R4.0 by the way.

I would be interested in this as well since I am in the same situation and have experienced the vchan error. I understand at least to some extent the vchan functionality as documented and I would suppose that your developers find a windows qube inherently risky since even the print spooler is “vulnerable by design” as Microsoft says about poin and print functionality. Steve Gibson opines that this should be their tag line for Windows 11.

Unfortunately, I “fixed” this for non-block devices (camera and good DAC) by adding a usb card to pci bus and assigning it to the window - 20 dollars not too bad a penalty and I just got tired of reading some of your code and wanted it fixed. I will note that usb cards that are self powered did not work after reboot. It looks like DOM0 doesn’t like to let go or windows gets confused even with your usb reset function. Windows will not see a self powered card unless I turn off the computer for a few days which I did to test.

:slight_smile: Rich 20 Dollars poorer but richer in audio

There are already some forum posts on this. Please chekout out first

And for the future release of Qubes (r4.1):

Continuing the discussion from Any way to make usb passtrough work with Windows 10 HVM?:

Thanks for the info deeplow/moderator but since I can’t stand audio or video lags I’ll stick with the 20 dollar fix. Looking forward to 4.1 but since at least for now Qubes 4.0 is my primary box with a pure windows surface laptop that I now only use with clients I am going to wait until the rc1.

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I’m stumped on this as well. Vchan error.
Afraid I can’t go for the USB controller workaround, since Windows won’t boot if I attach certain onboard controllers.

Offering a bounty of $15 to whoever can help me get this working. I just wanna play some games.

I think the vchan error basically means you can’t pass USB to Windows on R4.0.

I have a USB 3.1 port with a dedicated controller and I assigned the pci device to Windows but it doesn’t pick up my usb 3.0 flash drive. The device manager picks up the controller correctly. The funny thing is the usb-sys picks up the devices in my USB 3.1 port. The bios is set to legacy usb but turning it off didn’t help either.

I wonder if you pci passthrough only works with an external card as I’ve read some have done.