<html> <head> <meta http-equiv="content-type" content="text/html; charset=utf-8"> </head> <body bgcolor="#FFFFFF" text="#000000"> Up until about a week ago, I could pass through the USB controller for my front panel to my gaming VM and it would work just fine. Since then, though, and I'm not exactly sure what triggered it, it appears as if said controller isn't properly being released by the VM when it shuts down on its own (i.e : When I initiate a shutdown from within the guest and let it complete). Interestingly, getting libvirt to destroy the VM works just fine, and I can reboot without issues this way. On a "bad" shut down, virt-manager says the VM is "Shutting down" and won't let me do anything with it. Trying to use virsh directly doesn't seem to do anything, as the operation just blocks forever. Trying to restart libvirtd only makes it unresponsive. The Qemu logs for the VM themselves have this interesting bit : <blockquote> <pre>vfio : Cannot reset device 0000:00:14.0, no available reset mechanism </pre> </blockquote> Going back to earlier entries makes it seem like the USB controller always did this, although this line would usually be followed by something like this : <blockquote> <pre>terminating on signal 15 prom pid 8360 </pre> </blockquote> This no longer appears in newer entries. Trying to do a device remove/rescan blocks the shell with an unkillable task, while dmesg outputs this : <blockquote> <pre>vfio-pci 0000:00:14.0: Relaying device request to user (#0) vfio-pci 0000:00:14.0: Relaying device request to user (#10) vfio-pci 0000:00:14.0: Relaying device request to user (#20) vfio-pci 0000:00:14.0: Relaying device request to user (#30) vfio-pci 0000:00:14.0: Relaying device request to user (#40) vfio-pci 0000:00:14.0: Device is currently in use, task "bash" (2030) blocked until device is released </pre> </blockquote> Until I try to run that remove/rescan, the lspci still lists the device with this entry, which goes away after that even though the operation seemingly never completes : <blockquote> <div class="de1"> <pre>00:14.0 USB controller [0c03]: Intel Corporation 7 Series/C210 Series Chipset Family USB xHCI Host Controller [8086:1e31] (rev 04) Subsystem: Micro-Star International Co., Ltd. [MSI] Device [1462:7758] Kernel driver in use: xhci_hcd Kernel modules: xhci_pci </pre> </div> </blockquote> It looks just the same when the controller is attached to the host, even though none of what's plugged into it is listed by lsusb after I shutdown the VM. Can anyone tell me what's going on? I feel like I'm closing in on the solution, but I'm really not sure where to go from here. </body> </html>