kbdmux + ddb = hard freeze

[Yar Tikhiy]

Just to save other folks' time, I'd like to remind that using
Ctrl+Alt+Esc to escape to ddb still leads to the system freezing
hard if kbdmux is enabled--at least with a PS/2 keyboard.  I had
missed this issue when it was brought up here a month ago, so I
spent some time to find why my system was hanging dead.  Possible
workarounds found:

- remove kbdmux from the kernel configuration file

- disable kbdmux in device.hints:
    hint.kbdmux.0.disabled="1"

- go straight to remote gdb:
    sysctl debug.kdb.current=gdb
    sysctl debug.kdb.enter=1

-- 
Yar