Comment 15 for bug 1726367

I encountered this same error and was automagically pointed here by the bug reporting software.

Configuration: Dell Precision 7720, K17A (TB16) dock, Ubuntu 17.10 - live version, not installed. I had disabled USB security in BIOS prior to boot. Still running UEFI.

Booted a live 17.10 load from USB on the 7720 laptop. Everything was working when booting with dock plugged and all devices attached: ethernet, 2 displays, keyboard, and mouse.

When I tested hotplug, I encountered this same error.

Note that after the hotplug, both external displays and the laptop display worked correctly with extended display. Furthermore, the keyboard, mouse, and ethernet worked as well. It took a few seconds for everything to get recognized and restarted, but they did work.