On a NetBSD/mac68k 1.4_ALPHA system, April 10 sources, I was doing a
"make build" when I got a "panic: closef: count < 0"
I don't remember the exact stack trace, but ddb said curproc was "cc",
and the trace had sys_exit() and exit1() in it.

And for something likely mac68k-specific, I can't seem to be able to get
a crash dump anymore. If I break into ddb, then do "reboot 0x100", I
get:

syncing disks... done
vfs_unmountall: no context, aborting
NetBSD/mac68k does not trust itself to update the RTC on shutdown

dumping to dev 4,9 offset 73742
dump uvm_fault(0xf7b20, 0x161d000, 0, 0x1) -> 0x2
  type 8, code [mmu,ssw]: 505
trap type 8, code = 0x505, v = 0x161d189
kernel program counter = 0xddc40
kernel: MMU fault trap
Caught exception in ddb.

Stack trace looks lame and/or wrong this time: Debugger <- nmihand <-
lev7intr <- mi_switch <- tsleep <- uvm_scheduler, then another
uvm_fault.

When I tried to get a crash dump from the closef panic, I got a stack
trace that looked better, but I was too tired to type it in :) Had to do
with pmap_remove_mapping though. (And actually, 0xddc40 is
pmap_remove_mapping + 0x14e: cmpal a3@(0x4),a4... "show reg" says that
a3 is _proc0, a4 is _microtime. a3@(0x4) would try to deref a null
pointer).
-- 
Name: Dave Huang     |   Mammal, mammal / their names are called /
INet: khym@bga.com   |   they raise a paw / the bat, the cat /
FurryMUCK: Dahan     |   dolphin and dog / koala bear and hog -- TMBG
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