On a Ubuntu 18.10 host device with a gpu-passthrough kvm-qemu windows 10 client connection to a Delock PCIe 2x USB-A 3.1 gen2, I use an ATEN US224 Usb2.0 switch to redirect my keyboard and mouse between the Windows client and the Ubuntu host.
But for some reason after awhile when I switch back to the host neither the mouse or keyboard react to any input. I can switch it back to the host and everything works fine. But can't use the client until i reboot the computer.
Tonight I used
watch -n2 lsusb to keep track of if the devices just never connects. But I can see all of them connecting and disconnecting as they should.
Also the problem only appears after I have been using the client for awhile. So I have tried to remove all sleeping behaviors on both the client and host.