Subject: kernel crash and scsi-disk/hang
To: None <current-users@NetBSD.ORG>
From: Andrew Wheadon <>
List: current-users
Date: 01/22/1995 11:57:32
I'm having quite a few kernel crashes recently (about 2-3 per week)
and the accounting always seems to be corrupted when people
are using irc or screen-3.6, so I presume it's crashing when they
are running these programs for some time. I find it a bit frustrating
that when I do pop in to see what has happened the kernel has 
usually rebooted instead of staying in the Debugger to tell me
where it happened. (I have DDB and DIAGNOSTIC options in my configfile)

Anyway it sometimes seems to reboot while the slower of my two scsi-disks
(sd0) is being accessed, at least the light is still on both the 
disk and the controller while the other peripherals (sd1 and st0 are off).

This causes it to fail to find any scsi-peripherals and thus
ask for a boot-disk and then just wait until i come into work
and turn sd0 off and turn it on again, after this it finds 
them nicely on both a hard and a soft-reboot.

I can imagine that sd0 is being accessed too fast, at least 
our Novell-server has the same problem when the speed is set
too high on it's adaptec, but I don't know how to set the ncr
to different speeds for different devices and it seems to do
it itself anyway.

SO:	How do I make the kernel stop in debugger (for ever) 
	instead of rebooting.
	How do I set the speed for different devices on the
	How do I cause the scsi-bus to be reset properly on
	How do I find out which program is crashing my system
	or better still stop programs from being able to crash
	my System, without disabling user-access of the machine ?

I get no coredump when the machine crashes anyway.

Here is dmesg:

NetBSD 1.0A (WIPUX) #0: Fri Jan 20 09:43:25 MET 1995
CPU: Pentium (GenuineIntel 586-class CPU)
real mem  = 33161216
avail mem = 29646848
using 430 buffers containing 1761280 bytes of memory
isa0 (root)
npx0 at isa0 port 0xf0-0xff: using exception 16
WARNING: Pentium FDIV bug detected!
vt0 at isa0 port 0x60-0x6f irq 1: et4000, 80/132 col, color, 8 scr, mf2-kbd, [R3.00]
com0 at isa0 port 0x3f8-0x3ff irq 4: ns82450 or ns16450, no fifo
com1 at isa0 port 0x2f8-0x2ff irq 3: ns82450 or ns16450, no fifo
lpt0 at isa0 port 0x378-0x37f: polled
fdc0 at isa0 port 0x3f0-0x3f7 irq 6 drq 2
fd0 at fdc0 drive 0: 1.44MB 80 cyl, 2 head, 18 sec
ed0 at isa0 port 0x300-0x31f iomem 0xdc000-0xdffff irq 10: address 00:00:c0:c0:43:a0, type SMC8216/SMC8216C (16-bit) aui
root device eisa not configured
pci0 (root): configuration mode 2
pci0 bus 0 device 0: identifier 04a38086 class 06000011 not configured
pci0 bus 0 device 2: identifier 04828086 class 00000003 not configured
ncr0 at pci0 bus 0 device 5
pci_map_mem: memory mapped at c0000000-c0000fff
pci_map_int: pin A mapped to line 11
ncr0: restart (scsi reset).
ncr0 scanning for targets 0..6 ($Revision: 1.10 $)
scsibus0 at ncr0
probe(ncr0:0:0): 225ns (4 Mb/sec) offset 8.
ncr0 targ 0 lun 0: <FUJITSU, M2266S-512, 0020> SCSI2 0/direct fixed
sd0 at scsibus0: 1029MB, 1658 cyl, 15 head, 84 sec, 512 bytes/sec
probe(ncr0:1:0): 200ns (5 Mb/sec) offset 8.
ncr0 targ 1 lun 0: <FUJITSU, M2694S-512, 0124> SCSI2 0/direct fixed
sd1 at scsibus0sd1(ncr0:1:0): FAST SCSI-2 100ns (10 Mb/sec) offset 8.
: 1033MB, 1819 cyl, 15 head, 77 sec, 512 bytes/sec
ncr0 targ 5 lun 0: <HP, HP35470A, 1109> SCSI2 1/sequential removable
st0 at scsibus0: st0(ncr0:5:0): 200ns (5 Mb/sec) offset 8.
drive empty
biomask 840 netmask 41a ttymask 1a
changing root device to sd0a
sd1(ncr0:1:0): sd1(ncr0:1:0):
	^- these two messages appear while fsck is running.

this is my config file:
#	$NetBSD: GENERIC,v 1.7 1994/12/11 16:20:52 mycroft Exp $
#	GENERIC -- everything that's currently supported

machine		i386		# architecture, used by config; REQUIRED

options		I386_CPU	# CPU classes; at least one is REQUIRED
options		I486_CPU
options		I586_CPU
#options		MATH_EMULATE	# floating point emulation

options		DUMMY_NOPS	# speed hack; recommended

maxusers	32		# estimated number of users
options		TIMEZONE=0	# time zone to adjust RTC time by
options		DST=0		# daylight savings time used by RTC

options		SWAPPAGER	# paging; REQUIRED
options		VNODEPAGER	# mmap() of files
options		DEVPAGER	# mmap() of devices

options		DDB		# in-kernel debugger
options		DIAGNOSTIC	# internally consistency checks
#options		KTRACE		# system call tracing, a la ktrace(1)

options		SYSVMSG		# System V-like message queues
options		SYSVSEM		# System V-like semaphores
options		SYSVSHM		# System V-like memory sharing
#options	SHMMAXPGS=1024	# 1024 pages is the default

options		COMPAT_NOMID	# compatibility with 386BSD, BSDI, NetBSD 0.8,
options		COMPAT_09	# NetBSD 0.9,
options		COMPAT_10	# NetBSD 1.0,
options		COMPAT_43	# and 4.3BSD
options		TCP_COMPAT_42	# TCP bug compatibility with 4.2BSD

options	COMPAT_SVR4	# binary compatibility with SVR4
#options	COMPAT_IBCS2	# binary compatibility with SCO and ISC

options		USER_LDT	# user-settable LDT; used by WINE
options		LKM		# loadable kernel modules

options		FFS,QUOTA	# UFS and quotas
#options		LFS		# log-structured file system
options		MFS		# memory file system

options		NFSCLIENT	# Network File System client
options		NFSSERVER	# Network File System server

options		CD9660		# ISO 9660 + Rock Ridge file system
options		MSDOSFS		# MS-DOS file system
#options		FDESC		# /dev/fd
#options		KERNFS		# /kern
#options		NULLFS		# loopback file system
#options		PORTAL		# ?
#options		PROCFS		# /proc
#options		UMAPFS		# NULLFS + uid and gid remapping
#options		UNION		# union file system

#options	GATEWAY		# packet forwarding
options		INET		# IP + ICMP + TCP + UDP
#options		NS		# XNS
#options		ISO,TPIP	# OSI
#options		EON		# OSI tunneling over IP
#options		CCITT,LLC,HDLC	# X.25

config		netbsd	swap generic
options		GENERIC
options		WIPUX

isa0	at root
#eisa0	at root
pci0	at root

npx0	at isa? port 0xf0 irq 13	# math coprocessor

vt0	at isa? port 0x60 irq 1		# virtual PC console device

com0	at isa? port 0x3f8 irq 4	# standard PC serial ports
com1	at isa? port 0x2f8 irq 3

#lpt0	at isa? port 0x378 irq 7	# standard PC parallel ports
lpt0	at isa? port 0x378 		# polled ports (safer)
#lpt1	at isa? port 0x278

ncr*	at pci? bus ? dev ?		# NCR 538XX SCSI controllers
scsibus* at ncr?
# ahb*	at eisa? slot ? irq ?		# Adaptec 174[024] SCSI controllers
# scsibus* at ahb?
aha0	at isa? port 0x330 irq ? drq ?	# Adaptec 154[02] SCSI controllers
scsibus* at aha?
sd*	at scsibus? target ? lun ?	# SCSI disk drives
st*	at scsibus? target ? lun ?	# SCSI tape drives
cd*	at scsibus? target ? lun ?	# SCSI CD-ROM drives
ch*	at scsibus? target ? lun ?	# SCSI autochangers

fdc0	at isa? port 0x3f0 irq 6 drq 2	# standard PC floppy controllers
fd*	at fdc? drive ?

ed0	at isa? port 0x300 iomem 0xdc000 irq 10	# WD/SMC, 3C503, and NE[12]000
#ed1	at eisa? slot ? iomem 0xd0000 irq ?	# Eisa/SMC Card in ISA Mode ?

#sb0	at isa? port 0x220 irq 7 drq 1	# SoundBlaster
#spkr0	at isa? ...

pseudo-device	loop	1		# network loopback
pseudo-device	bpfilter 8		# packet filter
pseudo-device	sl	2		# CSLIP
pseudo-device	ppp	2		# PPP
pseudo-device	tun	2		# network tunneling over tty

pseudo-device	pty	64		# pseudo-terminals
pseudo-device	tb	1		# tablet line discipline
pseudo-device	vn	4		# paging to files

Well it might be the Fifos but I didn't think irc used fifos.
I've switched to using an mfs-mounted /tmp but it didn't help
much and some people are defining their own SCREENDIR.
The cost of living hasn't affected it's popularity. (unknown)
current	release=doc \ "NetBSD-current mirror"
hostbase=/mit/ftp/pub/NetBSD base=/usr prefix=/usr backup delete use-rel-suffix