CAM breaks USB [was Re: USB causing boot to hang]

[Steve Kargl]

On Sat, Dec 07, 2019 at 01:16:13AM +0100, Hans Petter Selasky wrote:
> 
> There is an option you can compile into the kernel which will allow the 
> keyboard to enter the debugger.
> 
> options	ALT_BREAK_TO_DEBUGGER
> 
> Sounds to me like either a leaked refcount or that one thread is 
> spinning blocking execution of other threads.
> 

I tried setting the sysctls

hw.usb.umass.debug: 1
hw.usb.xhci.debug: 1
hw.usb.uhci.debug: 1
hw.usb.ohci.debug: 1
hw.usb.ehci.debug: 1

but when I rebooted I forgot to request a verbose boot.
There was no apparent debugging output to the console.
I try again on Monday to get additional information.

-- 
Steve