Hi,

I tried the following:

ubik# uname -a
NetBSD ubik.bernstein.com 1.3_ALPHA NetBSD 1.3_ALPHA (UBIK) #0: Sun Nov  9 08:39:13 EST 1997     entropy@ubik.bernstein.com:/usr/src/sys/arch/pmax/compile/UBIK
ubik# [hit DO key to enter DDB]
ddb> break elf32_load_file
ddb> cont
After the continue, the machine locks up solid.  Even the halt key
doesn't work, I need to power cycle the machine.

It doesn't seem to matter what I choose for the breakpoint, I tried
many different locations all with the same result.

If I enter DDB and do other things, such as ps, then ``cont'' works OK
without wedging the machine.  Only setting a breakpoint seems to cause
the machine to hang.  Also, setting a breakpoint on a non-symbolic
address doesn't seem to help (e.g. if I use nm to find the address of
the symbol in the elf kernel)

The kernel was built from the config file included below.  netbsd.aout
was installed as /netbsd.

Sources are from 11/4/97.

ubik is a 5000/120 with 33MHz upgrade CPU module.

#
# DECstation 5000/240 kernel config
#
# 	$NetBSD: DS5000_100,v 1.6 1997/08/20 04:21:31 jonathan Exp $
#
include		"arch/pmax/conf/std.pmax"

maxusers	64

options 	MIPS1			# R2000/R3000 support (new)
#options 	MIPS3			# R4000/R4400 support (not finished)


# Support for specific models of DECstation
#options 	DS3100			# PMAX (kn01) DECstation 2100, 3100
#options 	DS5000_25		# MAXINE (kn02ca/xine) support
options 	DS5000_100		# 3MIN (kn02ba/kmin) support
#options 	DS5000_200		# 3MAX (kn02) support
#options 	DS5000_240		# 3MAXPLUS (kn03) support



# Standard system options
options 	DIAGNOSTIC		# extra kernel debugging checks
options 	DEBUG			# extra kernel debugging support
options 	"COMPAT_43"		# compatibility with 4.3BSD binaries
options 	KTRACE			# system call tracing support
options 	"NKMEMCLUSTERS=1024"	# 4K pages in kernel malloc pool
#options 	KGDB			# support for kernel gdb
#options 	"KGDBRATE=19200"	# kernel gdb port rate (default 9600)
#options 	"KGDBDEV=15*256+0"	# device for kernel gdb
#makeoptions DEBUG="-g"
options DDB

#options 	NTP			# network time protocol
#options 	UCONSOLE		# users can redirect console (unsafe)
options		COLORFONT_CACHE


# Filesystem options
file-system 	FFS             # fast filesystem with user and group quotas
file-system 	MFS		# memory-based filesystem
file-system 	NFS		# Sun NFS-compatible filesystem (client)
#file-system	KERNFS		# kernel data-structure filesystem
#file-system	FDESC		# user file descriptor filesystem
#file-system	UMAPFS		# uid/gid remapping filesystem
file-system 	NULLFS		# null layer filesystem
file-system	UNION
#file-system	LFS		# Log-based filesystem (still experimental)
#file-system	PORTAL		# portal filesystem (still experimental)

options 	FIFO		# POSIX fifo support (in all filesystems)
options 	NFSSERVER	# Sun NFS-compatible filesystem (server)

# Networking options
options 	INET		# Internet protocols
options 	"TCP_COMPAT_42"	# compatibility with 4.2BSD TCP/IP
#options 	GATEWAY		# IP packet forwarding
#options 	MULTICAST	# Multicast support
#options 	MROUTING	# Multicast routing support
#options 	ISO		# OSI networking
#options 	TPIP
#options 	EON

# NetBSD backwards compatibility
#options 	COMPAT_10	# NetBSD 1.0, (needed for X on 386?)
#options 	COMPAT_11	# NetBSD 1.1,
options 	COMPAT_12	# Netbsd 1.2 reboot()


# pmax specific
options 	COMPAT_ULTRIX	# ultrix compatibility
options 	EXEC_ECOFF	# Ultrix RISC binaries are ECOFF format
options 	"HZ=256"	# RTC rate required

config		netbsd root on ? type ?



########################################################################
###                   I/O bus and device options                     ###
########################################################################

# TC bus and supported options. (All but PMAXes have a turbochannel.)
include 	"arch/pmax/conf/tc.std"

# ioasic standard baseboard options (5000/2x, 5000/1xx, 5000/2[46]0)
include 	"arch/pmax/conf/builtin.ioasic"

# MAXINE-only ioasic baseboard devices and on-baseboard "options"
#include 	"arch/pmax/conf/builtin.maxine"

# Configuration for 3MAX (5000/200) which has turbochannel but no ASIC.
#include 	"arch/pmax/conf/builtin.3max"


# 2100/3100-only (aka PMAX aka KN01) baseboard devices.
# (may also be present on a 5100).
#include 	"arch/pmax/conf/builtin.3100"		# needed only on 2100/3100(/5100)


########################################################################
# SCSI configuration                                                   #
########################################################################

oldscsibus*	at asc?
#
# SCSI configuration for old 4.4bsd/pmax DECstation SCSI driver
#
include 	"arch/pmax/conf/scsi.pmax"
#include 	"arch/pmax/conf/mi.scsi"		# not yet supported


########################################################################
###                        Pseudo-devices                            ###
########################################################################

pseudo-device	sl		 4	# serial-line IP ports
#pseudo-device   ppp              2      # serial-line IP ports
pseudo-device	pty		64	# pseudo ptys
pseudo-device	bpfilter	16	# packet filter ports
pseudo-device	loop
pseudo-device	vnd		4	# virtual disk ick
pseudo-device   ccd             4       # concatenated disks

#pseudo-device	ether			# From old config. what does it mean?
pseudo-device	rasterconsole	1 	# NB: raster console requires "fb"
pseudo-device	fb		1	# up to 3 framebuffers

--
entropy -- it's not just a good idea, it's the second law.