Hi, Gerd My Qemu version is 1.5.1, and use libusb for usb pass through. I pass through a host usb device to the guest by bus number and physical port, when I unplug the usb device from the host, and plug in on the same physical port immediately, but the usb device don't show up in the guest. The qemu log show: libusb_release_interface: -4 [NO_DEVICE] libusbx: error [_get_usbfs_fd] libusbx couldn't open USB device /dev/bus/usb/002/004: No such file or directory libusbx: error [_get_usbfs_fd] libusbx couldn't open USB device /dev/bus/usb/002/004: No such file or directory libusbx: error [_get_usbfs_fd] libusbx couldn't open USB device /dev/bus/usb/002/004: No such file or directory
I find the reason is that the global libusb_context has recorded the usb devices' devnum, but when the host device was unplugged and plugged from the host, the devnum will change, finally cause the problem. Any ideas ? Thanks! Best Regards! -Gonglei