While ttyflags appeared to be hanging (booting with GENERIC-52), I can
drop into the debugger, and trace to get:

	_Debugger
	_nmihand
	_lev7intr
	_zsc_intr_hard
	_zshard
	_lev4intr
	_spec_open
	_vn_open
	_sys_open
	_syscall(5)
	_trap0

I didn't copy down all those memory addresses that were arguments for
these function calls, but if they are really needed, I can always get
them.

So, from my (very poor) understanding of what is happening, it seems
that the zs code is stuck after masking all interrupts.

For the record, I run an LC III + FPU.  Using the most current BETA
sets and GENERIC-47, I can boot to multiuser and talk to my modem
attached to tty00 without incident.  Using any newer kernel, the
system hangs when trying to set ttyflags on tty00.

--
   Johnny C. Lam
   Department of Statistics                 lamj@stat.cmu.edu
   Carnegie Mellon University               http://www.stat.cmu.edu/~lamj/

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