kern/112707: 6.2-STABLE panic: spoiling cp->ace = 3

[Eugene Grosbein]

>Number:         112707
>Category:       kern
>Synopsis:       6.2-STABLE panic: spoiling cp->ace = 3
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Wed May 16 11:20:02 GMT 2007
>Closed-Date:
>Last-Modified:
>Originator:     Eugene Grosbein
>Release:        FreeBSD 6.2-STABLE i386
>Organization:
Svyaz Service JSC
>Environment:
System: FreeBSD gw1.svzserv.kuzbass.ru 6.2-STABLE FreeBSD 6.2-STABLE #2: Thu Apr 26 17:48:06 UTC 2007 root at gw1.svzserv.kuzbass.ru:/home/obj/home/src/sys/GW1 i386

>Description:
	I use Transcend IDE Flash for diskless NanoBSD installation.
	It works pretty nice: BIOS detects it as 128M hard drive,
	NanoBSD boots and works flawlessly, I can even do remote upgrade:
	/dev/ad0 is divided to two slices and I may download
	new slice image into second slice (sysctl kern.geom.debugflags=16).
	After that, I need to change default slice for boot0:

boot0cfg -s 2 ad0

	This command works also, but after that all access
	to (mounted r/o) root partition fails with kernel message
	g_vfs_done about READ error. I need to power cycle machine
	to reboot it, it reboots and I see that boot0cfg did the job.
	However, this it not suitable for remote server.

	The kernel compiled with options INVARIANTS did not complete
	updating boot0 with mentioned command but panices immediately:

panic: spoiling cp->ace = 3

	This NanoBSD installation does not have dump device for crashdump
	by default and I have not one handy. But I hope it's possible
	to add IDE drive to the system and make dump device on it, if needed.

>How-To-Repeat:
	
	Kernel config file follows.

options		INCLUDE_CONFIG_FILE

machine		i386
cpu		I686_CPU
ident		GW
maxusers	0

options 	SCHED_4BSD		# 4BSD scheduler
options 	PREEMPTION		# Enable kernel thread preemption

options		CLK_USE_I8254_CALIBRATION

options 	INET			#InterNETworking
options 	FFS			#Berkeley Fast Filesystem
#options 	SOFTUPDATES		#Enable FFS soft updates support
options 	COMPAT_43		#Compatible with BSD 4.3 [KEEP THIS!]
options 	_KPOSIX_PRIORITY_SCHEDULING # POSIX P1003_1B real-time extensions
options 	KTRACE			#ktrace(1) support

device		acpi

device		isa
device		pci

# Floppy drives
device		fdc

# atkbdc0 controls both the keyboard and the PS/2 mouse
device		atkbdc
device		atkbd

options 	ATKBD_DFLT_KEYMAP	# specify the built-in keymap
makeoptions	ATKBD_DFLT_KEYMAP=ru.koi8-r

device		vga

# syscons is the default console driver, resembling an SCO console
device		sc
options		SC_HISTORY_SIZE=1000
options 	SC_DFLT_FONT		# compile font in
makeoptions	SC_DFLT_FONT=cp866

# Floating point support - do not disable.
device		npx

# Serial (COM) ports
device		sio
device		em

# PCI Ethernet NICs that use the common MII bus controller code.
# NOTE: Be sure to keep the 'device miibus' line in order to use these NICs!
device		miibus		# MII bus support
#device		rl		# RealTek 8129/8139
device		fxp		# Intel EtherExpress PRO/100B (82557, 82558)
device		sk

# Pseudo devices
device		loop			# Network loopback
device		mem
device		io
device		random
device		ether		# Ethernet support
device		ppp		# Kernel PPP
device		tun		# Packet tunnel.
device		pty		# Pseudo-ttys (telnet etc)
device		snp
device		md
device		gif		# IPv6 and IPv4 tunneling
device		vlan

# The `bpf' pseudo-device enables the Berkeley Packet Filter.
# Be aware of the administrative consequences of enabling this!
device		bpf		#Berkeley packet filter

device		ata
device		atadisk		# ATA disk drives

# USB support
#device		uhci		# UHCI PCI->USB interface
#device		usb		# USB Bus (required)
#device		umass		# Disks/Mass storage - Requires scbus and da

#device		scbus		# SCSI bus (required for SCSI)
#device		da		# Direct Access (disks)
#device		pass		# Passthrough device (direct SCSI access)

options		NO_SWAPPING

options 	IPFIREWALL
options 	IPFIREWALL_VERBOSE
options 	IPDIVERT
options 	IPFIREWALL_FORWARD
options		DUMMYNET
options		IPSEC
options		IPSEC_ESP
options		IPSEC_FILTERGIF

options 	HZ=1000
options		DEVICE_POLLING

options		ALT_BREAK_TO_DEBUGGER
options		KDB                     # Enable kernel debugger support.
options		KDB_TRACE
options		KDB_UNATTENDED

options		INVARIANTS
options		INVARIANT_SUPPORT

>Fix:

	Unknown for me

>Release-Note:
>Audit-Trail:
>Unformatted: