Re: 3.18 regression: Error while assigning device slot ID, USB3 devices not detected

[Greg KH <gregkh@linuxfoundation.org>]

On Sun, Jan 18, 2015 at 12:08:18AM -0600, Robert Hancock wrote:
> I've got an Intel Haswell-based system with a Gigabyte Z87X-D3H motherboard
> under Fedora 21. After updating to the 3.18.2-200 Fedora kernel, I noticed
> some errors in dmesg and at least some of my USB3 ports don't recognize any
> USB3 devices plugged into them:
> 
> [    0.560838] xhci_hcd 0000:00:14.0: Error while assigning device slot ID
> [    0.560912] xhci_hcd 0000:00:14.0: Max number of devices this xHCI host
> supports is 32.
> [    0.560990] usb usb2-port2: couldn't allocate usb_device
> [    0.561098] xhci_hcd 0000:00:14.0: Error while assigning device slot ID
> [    0.561163] xhci_hcd 0000:00:14.0: Max number of devices this xHCI host
> supports is 32.
> [    0.561239] usb usb2-port5: couldn't allocate usb_device
> [    0.561344] xhci_hcd 0000:00:14.0: Error while assigning device slot ID
> [    0.561409] xhci_hcd 0000:00:14.0: Max number of devices this xHCI host
> supports is 32.
> [    0.561484] usb usb2-port6: couldn't allocate usb_device
> 
> This worked fine under 3.17. Is this a known problem?

Yes it is, should be fixed in Linus's tree now and will be backported to
the latest 3.18-stable tree in a week or so.

thanks,

greg k-h