I wasn't at my computer at the time of the crash.  The only thing
happening as far as I know was a sup (over my slip link).  It's the
first crash I've had in a long time.

Here's the info I got out of the kernel debugger before rebooting:
----------------------------------------------------------------------
vm_fault(f81b78c8, 0, 1, 0) -> 5
kernel: page fault trap, code=0
Stopped at      _ip_stripoptions+0x16d: movzbl  0x57(%eax),%eax
db> trace
_ip_stripoptions(f8442100,0) at _ip_stripoptions+0x16d
_ipintr(f7bffdf0,80000000,f81cc834,f8144715,f81a62f8) at _ipintr+0x268
_Xsoftnet(0,f811a960,f7bffdc0,f8107ee3,0) at _Xsoftnet+0x28
_pffasttimo(0) at _pffasttimo+0x23
_softclock(f7bffdf0,f81b28e0,0,ffffffff,f7bffde4) at _softclock+0x77
_hardclock(f7bffdf0,f7bffe54,f81014d7,f7bffdf0,0) at _hardclock+0x20d
_clockintr(f7bffdf0) at _clockintr+0xb
_Xintr0(f81b3390,118,f8111980,afc80,f843db00) at _Xintr0+0x5b
_select(f843db00,f7bfff94,f7bfff8c,0,800) at _select+0x26c
_syscall() at _syscall+0x12b
--- syscall (number 93) ---
0x1007222d:
db> show registers
cs          0xf7bf0008
ds          0xf8440010  _end+0x26e5b8
es                0x10
ss                0x10
eax                  0
ecx         0xf8442100  _end+0x2706a8
edx                0x2
ebx         0xf81c5508  _ipforward_rt+0x4
esp         0xf7bffd28  _kstack+0x1d28
ebp         0xf7bffd58  _kstack+0x1d58
esi         0xf843df00  _end+0x26c4a8
edi         0xf844212c  _end+0x2706d4
eip         0xf8140771  _ip_stripoptions+0x16d
efl            0x10286
_ip_stripoptions+0x16d: movzbl  0x57(%eax),%eax
db> 
----------------------------------------------------------------------

Here's my config (trimmed of comments):
----------------------------------------------------------------------
machine		"i386"
ident		EXCELSIOR
cpu		"I486_CPU"
options		MATH_EMULATE
options		MACHINE_NONCONTIG
timezone	5 dst
maxusers	32
maxfdescs	2048
options		SWAPPAGER,VNODEPAGER,DEVPAGER
options		KTRACE
options		FIFO
options		SYSVMSG,SYSVSEM,SYSVSHM
options		LKM
options		SCSI,QUOTA,MFS,FFS
options		NFSSERVER,NFSCLIENT,MSDOSFS
options		FDESC,KERNFS
options		INET,NS,ISO,TPIP,EON,CCITT,MULTICAST,GATEWAY
options		DDB
options		"USER_LDT"
options		"COMPAT_NOMID"
options		"COMPAT_43"
options		"TCP_COMPAT_42"
options		XSERVER,UCONSOLE
options		"PCVT_META_ESC=1"

config		netbsd	root on wd0 swap on wd0 and sd0

controller	isa0

device		vt0	at isa? port "IO_KBD" irq 1

device		npx0	at isa? port "IO_NPX" irq 13

device		com0	at isa? port "IO_COM1" irq 4
device		com1	at isa? port "IO_COM2" irq 3
device		com2	at isa? port "IO_COM3" irq 9

device		lpt0	at isa? port "IO_LPT3"

controller	wdc0	at isa? port "IO_WD1" irq 14
disk		wd0	at wdc0 drive ?

controller	fdc0	at isa? port "IO_FD1" irq 6 drq 2
disk		fd0	at fdc0 drive ?
disk		fd1	at fdc0 drive ?

controller	uha0	at isa? port 0x340 irq 11 drq 5
master		scsibus0 at uha0
device		sd0	at scsibus0 slave ?
device		st0	at scsibus0 slave ?

pseudo-device pty	64
pseudo-device loop
pseudo-device ether #XXX
pseudo-device log
pseudo-device bpfilter	4
pseudo-device sl	2
pseudo-device ppp
pseudo-device vn	4
pseudo-device speaker
pseudo-device tb
----------------------------------------------------------------------

	Mark
--------------------------------------------------------------------
Email: Mark_Weaver@brown.edu           | Brown University
PGP Key: finger mhw@cs.brown.edu       | Dept of Computer Science

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