(unknown charset) 6.0-BETA3 - ffs_blkfree: freeing free block panic

Hi.

I'm seeing this occuring on two boxes, one built Aug 23 and the
other Aug 31. The panic occurs under moderate disk I/O. I suspect
that a commit made in HEAD on 31/7/2005 (by ups_at_freebsd.org) to
src/sys/ufs/ffs/ffs_softdep.c (1.182) and src/sys/ufs/ffs/softdep.h
(1.18) are related. I'll pull those across from a -current box and
see if it makes a difference. But just for those looking for feedback
for 6-RELENG;

[citadel] /var/crash# kgdb /usr/src/sys/i386/compile/CITADEL5/kernel.debug vmcore.8
[GDB will not be able to debug user-mode threads: /usr/lib/libthread_db.so: Undefined symbol "ps_pglobal_lookup"]
GNU gdb 6.1.1 [FreeBSD]
Copyright 2004 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "i386-marcel-freebsd".

Unread portion of the kernel message buffer:
Á¸ÁøÁ¨±Á_at_ qÁdb) backtrace
#0  doadump () at pcpu.h:165
#1  0xc0501c7c in boot (howto=260) at ../../../kern/kern_shutdown.c:397
#2  0xc0501fd1 in panic (fmt=0xc06b958c "ffs_blkfree: freeing free block")
     at ../../../kern/kern_shutdown.c:553
#3  0xc05ef36f in ffs_blkfree (ump=0xc1c15a00, fs=0xc1c2f000,
     devvp=0xc1c5ecc0, bno=4, size=16384, inum=4)
     at ../../../ufs/ffs/ffs_alloc.c:1847
#4  0xc05fde18 in handle_workitem_freeblocks (freeblks=0xc422b300, flags=0)
     at ../../../ufs/ffs/ffs_softdep.c:2588
#5  0xc05fae3c in process_worklist_item (matchmnt=0x0, flags=0)
     at ../../../ufs/ffs/ffs_softdep.c:836
#6  0xc05faadc in softdep_process_worklist (matchmnt=0x0)
     at ../../../ufs/ffs/ffs_softdep.c:700
#7  0xc055961d in sched_sync () at ../../../kern/vfs_subr.c:1623
#8  0xc04ebd95 in fork_exit (callout=0xc055933c <sched_sync>, arg=0x0,
     frame=0xd5295d38) at ../../../kern/kern_fork.c:789
#9  0xc065a78c in fork_trampoline () at ../../../i386/i386/exception.s:208
(kgdb)

dmesg shows
Copyright (c) 1992-2005 The FreeBSD Project.
Copyright (c) 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993, 1994
         The Regents of the University of California. All rights reserved.
FreeBSD 6.0-BETA3 #0: Tue Aug 23 23:53:09 SAST 2005
     root_at_:/usr/src/sys/i386/compile/CITADEL5
WARNING: debug.mpsafenet forced to 0 as ipsec requires Giant
WARNING: MPSAFE network stack disabled, expect reduced performance.
Timecounter "i8254" frequency 1193182 Hz quality 0
CPU: Intel(R) Celeron(R) CPU 2.00GHz (1999.95-MHz 686-class CPU)
   Origin = "GenuineIntel"  Id = 0xf29  Stepping = 9
   Features=0xbfebfbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,C
MOV,PAT,PSE36,CLFLUSH,DTS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE>
   Features2=0x4400<CNTX-ID,<b14>>
real memory  = 528416768 (503 MB)
avail memory = 507617280 (484 MB)
ACPI APIC Table: <P4M266 AWRDACPI>
ioapic0 <Version 0.3> irqs 0-23 on motherboard
npx0: [FAST]
npx0: <math processor> on motherboard
npx0: INT 16 interface
acpi0: <P4M266 AWRDACPI> on motherboard
acpi0: Power Button (fixed)
pci_link0: <ACPI PCI Link LNKA> on acpi0
pci_link1: <ACPI PCI Link LNKB> on acpi0
pci_link2: <ACPI PCI Link LNKC> irq 11 on acpi0
pci_link3: <ACPI PCI Link LNKD> on acpi0
pci_link4: <ACPI PCI Link ALKA> irq 0 on acpi0
pci_link5: <ACPI PCI Link ALKB> irq 0 on acpi0
pci_link6: <ACPI PCI Link ALKC> irq 0 on acpi0
pci_link7: <ACPI PCI Link ALKD> irq 0 on acpi0
Timecounter "ACPI-fast" frequency 3579545 Hz quality 1000
acpi_timer0: <24-bit timer at 3.579545MHz> port 0x408-0x40b on acpi0
cpu0: <ACPI CPU> on acpi0
acpi_button0: <Power Button> on acpi0
pcib0: <ACPI Host-PCI bridge> port 0xcf8-0xcff on acpi0
pci0: <ACPI PCI bus> on pcib0
agp0: <VIA 8703 (P4M266x/P4N266) host to PCI bridge> mem 0xeb000000-0xeb7fffff a
t device 0.0 on pci0
pcib1: <PCI-PCI bridge> at device 1.0 on pci0
pci1: <PCI bus> on pcib1
pci1: <display, VGA> at device 0.0 (no driver attached)
fxp0: <Intel 82550 Pro/100 Ethernet> port 0xd000-0xd03f mem 0xeb820000-0xeb820ff
f,0xeb800000-0xeb81ffff irq 18 at device 8.0 on pci0
miibus0: <MII bus> on fxp0
inphy0: <i82555 10/100 media interface> on miibus0
inphy0:  10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto
fxp0: Ethernet address: 00:02:b3:ed:ec:a2
fxp0: [GIANT-LOCKED]
isab0: <PCI-ISA bridge> at device 17.0 on pci0
isa0: <ISA bus> on isab0
atapci0: <VIA 8235 UDMA133 controller> port 0x1f0-0x1f7,0x3f6,0x170-0x177,0x376,
0xe000-0xe00f at device 17.1 on pci0
ata0: <ATA channel 0> on atapci0
ata1: <ATA channel 1> on atapci0
acpi_tz0: <Thermal Zone> on acpi0
fdc0: <floppy drive controller> port 0x3f0-0x3f5,0x3f7 irq 6 drq 2 on acpi0
fdc0: [FAST]
sio0: <16550A-compatible COM port> port 0x3f8-0x3ff irq 4 flags 0x10 on acpi0
sio0: type 16550A
ppc0: <Standard parallel printer port> port 0x378-0x37f irq 7 on acpi0
ppc0: Generic chipset (NIBBLE-only) in COMPATIBLE mode
ppbus0: <Parallel port bus> on ppc0
plip0: <PLIP network interface> on ppbus0
lpt0: <Printer> on ppbus0
lpt0: Interrupt-driven port
ppi0: <Parallel I/O> on ppbus0
pmtimer0 on isa0
orm0: <ISA Option ROM> at iomem 0xcc000-0xcd7ff on isa0
atkbdc0: <Keyboard controller (i8042)> at port 0x60,0x64 on isa0
atkbd0: <AT Keyboard> irq 1 on atkbdc0
kbd0 at atkbd0
atkbd0: [GIANT-LOCKED]
sc0: <System console> at flags 0x100 on isa0
sc0: VGA <16 virtual consoles, flags=0x300>
sio1: configured irq 3 not in bitmap of probed irqs 0
sio1: port may not be enabled
vga0: <Generic ISA VGA> at port 0x3c0-0x3df iomem 0xa0000-0xbffff on isa0
Timecounter "TSC" frequency 1999953780 Hz quality 800
Timecounters tick every 1.000 msec
IPsec: Initialized Security Association Processing.
ipfw2 (+ipv6) initialized, divert loadable, rule-based forwarding disabled, defa
ult to deny, logging unlimited
ad0: 39266MB <HDS722540VLAT20 V31OA6EA> at ata0-master UDMA100
ad2: 39266MB <HDS722540VLAT20 V31OA6EA> at ata1-master UDMA100
Trying to mount root from ufs:/dev/ad0s1a
fxp0: Microcode loaded, int_delay: 1000 usec  bundle_max: 6
fxp0: Microcode loaded, int_delay: 1000 usec  bundle_max: 6
fxp0: Microcode loaded, int_delay: 1000 usec  bundle_max: 6
fxp0: Microcode loaded, int_delay: 1000 usec  bundle_max: 6
fxp0: Microcode loaded, int_delay: 1000 usec  bundle_max: 6
fxp0: Microcode loaded, int_delay: 1000 usec  bundle_max: 6
Accounting enabled

Khetan Gajjar.
--
khetan_at_os.org.za
+27 82 885 4047