[vfio-users] USB device passthrough regression?

[Patrick O'Callaghan]

On Sat, 2017-10-28 at 12:58 +0100, Patrick O'Callaghan wrote:
> I've been using a USB-attached slide scanner (Ion Slidesforever) under
> a Windows 10 VM using QEMU/KVM USB passthrough, however it has now
> stopped working.
> 
> The device still shows up under the Windows "device manager" console,
> and the scanner app doesn't complain that it can't find it. The scanner
> works correctly on a Windows laptop so the hardware is fine. I've also
> removed and reinstalled the app (you never know with Windows) but with
> no improvement.
> 
> Under the VM the app launches but doesn't appear to receive any input,
> nor does it give an error message. Removing and reattaching the device
> in the virt-manager console (and rebooting the VM) makes no difference.
> 
> Using xsane under Linux does capture an image, but unfortunately not at
> full resolution, so I need the proprietary Windows app and driver to
> work.
> 
> This may have nothing to do with VFIO, but I thought I'd ask in case
> anyone has seen something similar. I have several thousand slides to
> get through :-(
> 
> poc

Oops, I should have mentioned I'm using qemu-kvm-2.9.1-1.fc26.x86_64
under Fedora with kernel 4.13.9-200.fc26.x86_64. The last time I'm sure
this worked was with qemu-kvm-2.4.1-10.fc23.x86_64 and kernel 4.11.

poc