Description of problem: The guest has a host-usb device(Kingston Technology DataTraveler 100 G3/G4/SE9 G2), which is attached to xhci controller(on host). Qemu will stuck if I detach it from guest.
How reproducible: 100% Steps to Reproduce: 1. Use usb stick to copy files in guest , make it busy working. 2. virsh detach-device vm_name usb.xml Then qemu will stuck for 20s, I found this is because libusb_release_interface block for 20s. Dmesg prints: [35442.034861] usb 4-2.1: Disable of device-initiated U1 failed. [35447.034993] usb 4-2.1: Disable of device-initiated U2 failed. [35452.035131] usb 4-2.1: Set SEL for device-initiated U1 failed. [35457.035259] usb 4-2.1: Set SEL for device-initiated U2 failed. Is this a hardware error or software's bug?