Comment 41 for bug 1546641

Many thanks Martin.

Trawling through the linux-usb and distro kernel mailing list archives shows that the kernel blocking problem has been around for some time and discussed at length.

What it seems to boil down to is this:
https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/tree/drivers/usb/core/hub.c#n67

The fact that parameters exist to force or fallback to the old initialisation scheme indicates the kernel devs. are aware there could be problems with the way USB devices are initialised, depending on the USB device.