Comment 109 for bug 1419355

(In reply to Peter Maciejko from comment #105)
> Hello, first of all I would like to say thank you for your effort.
>
> I have H87 PRO 4 motherboard and same issue with reboot after shutdown. What
> kind of information do you need? I am Python developer and I need my machine
> to work. With this bug my computer is almost unusable. I can provide you all
> information and data you want, just fix this please.
> I have tried manually setpci. I can not remove xhci_hcd from kernel, after
> make
> #sudo modprobe -r xhci_hcd beacause I get this info: "Can not remove module.
> Module is built-in".
>
> Nothing works. Intel USB controller is my only xhci device. Please help me
> fastest as you can.

Since you have a kernel with built in xhci (unlike the Arch example given above) you need to set it on the kernel command line. In /etc/default/grub, there should be a line like:
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

Add to the end of it before the quotes the extra argument of (try the other quirk numbers mentioned above if this one doesn't work): xhci_hcd.quirks=270336

I think you then run "sudo update-grub" on Ubuntu to regenerate the grub config with this change. Not sure, it's been a while since I last used Ubuntu and most of my machines boot with gummiboot.