FreeBSD 8.0-CUURENT/amd64 coredumps when shutdown

Hello.
I have a difficult problem and apart from possible hardware problems I 
need to track down problems.
My lab's box is a Intel Q6600 driven box with a ASUS P5K-Deluxe WiFi 
mainboard (Intel P35 chipset, ICH9, 8GB DDR2-800 RAM).

Symptomatics:

Whenever I shutdown or reboot the box, it dumps a core! This happens 
only if the box is in multiuser mode.
First I suspected the new 'drm' code, but disabling every module loading 
and even with X11-free environment the box dies when shutting down or 
reboot.
The weir thing is: I realised this faulty behaviour before the upgrade 
to FreeBSD 6.0-CURRENT/amd64 I did last week when the box ran FreeBSD 
7.1-STABLE/amd64. Whenever I left a Xsession, the box died. Whenever I 
rebootet it, the box died.

I already checked cabling and SMART logs of the harddrives making sure 
there is no issue with lost blocks or similar. Then I tried testing 
memory, but also with no success finding an issue.

A weird behaviour is: whenever I load drm.ko module on that box 
(remember, P35/ICH9/Q6600, that means NO AGP!) agp.ko gets also loaded. 
None of the other 8.0-CURRENT/amd64 boxes with PCIe hardware show that 
behaviour (most of them are older).

Well, I saw this strange crashing-behaviour prior to that of my desk's 
box on one of our DELL PowerEdge 1950 III server days before. That box 
is running FreeBSD 8.0-CURRENT/amd64 on two 4-core XEONs. Whenever I 
rebootet that box, I got a coredump. That vanished now with the mature 
of the 8.0-CURRENT sourcs, but it occurs now for the desktop box.

I can not provide a sophisticated core or a screendump of the log 
message since I need the box by the end of the week due to some 
conference prapartions (so all of the debugging stuff has been 
disabled), but I will provide more by next week if this issue seems not 
familiar to someone.

By the way, BIOS of the board is 1101 - newest on market for that mobo.

I'm open for some hints and tips tracking down the issue ...

A dmesg output is provided.

Regards,
Oliver

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FreeBSD 8.0-CURRENT #2 r189870: Mon Mar 16 09:03:05 UTC 2009
    root_at_telesto.geoinf.fu-berlin.de:/usr/obj/usr/src/sys/TELESTO
Timecounter "i8254" frequency 1193182 Hz quality 0
CPU: Intel(R) Core(TM)2 Quad CPU    Q6600  _at_ 2.40GHz (3013.58-MHz K8-class CPU)
  Origin = "GenuineIntel"  Id = 0x6fb  Stepping = 11
  Features=0xbfebfbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CLFLUSH,DTS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE>
  Features2=0xe3bd<SSE3,DTES64,MON,DS_CPL,VMX,EST,TM2,SSSE3,CX16,xTPR,PDCM>
  AMD Features=0x20100800<SYSCALL,NX,LM>
  AMD Features2=0x1<LAHF>
  TSC: P-state invariant
  Cores per package: 4
usable memory = 8579391488 (8181 MB)
avail memory  = 8283136000 (7899 MB)
ACPI APIC Table: <A_M_I_ OEMAPIC >
FreeBSD/SMP: Multiprocessor System Detected: 4 CPUs
 cpu0 (BSP): APIC ID:  0
 cpu1 (AP): APIC ID:  1
 cpu2 (AP): APIC ID:  2
 cpu3 (AP): APIC ID:  3
ioapic0 <Version 2.0> irqs 0-23 on motherboard
kbd1 at kbdmux0
netsmb_dev: loaded
cryptosoft0: <software crypto> on motherboard
acpi0: <A_M_I_ OEMXSDT> on motherboard
acpi0: [ITHREAD]
acpi0: Power Button (fixed)
acpi0: reservation of 0, a0000 (3) failed
acpi0: reservation of 100000, cff00000 (3) failed
Timecounter "ACPI-safe" frequency 3579545 Hz quality 850
acpi_timer0: <24-bit timer at 3.579545MHz> port 0x808-0x80b on acpi0
acpi_hpet0: <High Precision Event Timer> iomem 0xfed00000-0xfed003ff on acpi0
Timecounter "HPET" frequency 14318180 Hz quality 900
pcib0: <ACPI Host-PCI bridge> port 0xcf8-0xcff on acpi0
pci0: <ACPI PCI bus> on pcib0
pcib1: <ACPI PCI-PCI bridge> irq 16 at device 1.0 on pci0
pci1: <ACPI PCI bus> on pcib1
vgapci0: <VGA-compatible display> port 0xb000-0xb0ff mem 0xd0000000-0xdfffffff,0xfe8e0000-0xfe8effff irq 16 at device 0.0 on pci1
hdac0: <ATI RV730 High Definition Audio Controller> mem 0xfe8fc000-0xfe8fffff irq 17 at device 0.1 on pci1
hdac0: HDA Driver Revision: 20090226_0129
hdac0: [ITHREAD]
uhci0: <Intel 82801I (ICH9) USB controller> port 0xa800-0xa81f irq 16 at device 26.0 on pci0
uhci0: [ITHREAD]
uhci0: LegSup = 0x0f30
usbus0: <Intel 82801I (ICH9) USB controller> on uhci0
uhci1: <Intel 82801I (ICH9) USB controller> port 0xa880-0xa89f irq 21 at device 26.1 on pci0
uhci1: [ITHREAD]
uhci1: LegSup = 0x0f30
usbus1: <Intel 82801I (ICH9) USB controller> on uhci1
uhci2: <Intel 82801I (ICH9) USB controller> port 0xac00-0xac1f irq 18 at device 26.2 on pci0
uhci2: [ITHREAD]
uhci2: LegSup = 0x0f30
usbus2: <Intel 82801I (ICH9) USB controller> on uhci2
ehci0: <Intel 82801I (ICH9) USB 2.0 controller> mem 0xfe7ffc00-0xfe7fffff irq 18 at device 26.7 on pci0
ehci0: [ITHREAD]
usbus3: EHCI version 1.0
usbus3: <Intel 82801I (ICH9) USB 2.0 controller> on ehci0
hdac1: <Intel 82801I High Definition Audio Controller> mem 0xfe7f8000-0xfe7fbfff irq 22 at device 27.0 on pci0
hdac1: HDA Driver Revision: 20090226_0129
hdac1: [ITHREAD]
pcib2: <ACPI PCI-PCI bridge> irq 17 at device 28.0 on pci0
pci4: <ACPI PCI bus> on pcib2
pcib3: <ACPI PCI-PCI bridge> irq 17 at device 28.4 on pci0
pci3: <ACPI PCI bus> on pcib3
atapci0: <JMicron AHCI controller> mem 0xfeafe000-0xfeafffff irq 16 at device 0.0 on pci3
atapci0: [ITHREAD]
atapci0: AHCI Version 01.00 controller with 2 ports PM supported
ata2: <ATA channel 0> on atapci0
ata2: [ITHREAD]
ata3: <ATA channel 1> on atapci0
ata3: [ITHREAD]
atapci1: <JMicron JMB363 UDMA133 controller> port 0xdc00-0xdc07,0xd880-0xd883,0xd800-0xd807,0xd480-0xd483,0xd400-0xd40f at device 0.1 on pci3
atapci1: [ITHREAD]
ata4: <ATA channel 0> on atapci1
ata4: [ITHREAD]
pcib4: <ACPI PCI-PCI bridge> irq 16 at device 28.5 on pci0
pci2: <ACPI PCI bus> on pcib4
mskc0: <Marvell Yukon 88E8056 Gigabit Ethernet> port 0xc800-0xc8ff mem 0xfe9fc000-0xfe9fffff irq 17 at device 0.0 on pci2
msk0: <Marvell Technology Group Ltd. Yukon EC Ultra Id 0xb4 Rev 0x03> on mskc0
can't re-use a leaf (jabbers)!
msk0: Ethernet address: 00:1d:60:a6:fa:74
miibus0: <MII bus> on msk0
e1000phy0: <Marvell 88E1149 Gigabit PHY> PHY 0 on miibus0
e1000phy0:  10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, 1000baseTX-FDX, auto
mskc0: [FILTER]
uhci3: <Intel 82801I (ICH9) USB controller> port 0xa080-0xa09f irq 23 at device 29.0 on pci0
uhci3: [ITHREAD]
uhci3: LegSup = 0x0f30
usbus4: <Intel 82801I (ICH9) USB controller> on uhci3
uhci4: <Intel 82801I (ICH9) USB controller> port 0xa400-0xa41f irq 19 at device 29.1 on pci0
uhci4: [ITHREAD]
uhci4: LegSup = 0x0f30
usbus5: <Intel 82801I (ICH9) USB controller> on uhci4
uhci5: <Intel 82801I (ICH9) USB controller> port 0xa480-0xa49f irq 18 at device 29.2 on pci0
uhci5: [ITHREAD]
uhci5: LegSup = 0x0f30
usbus6: <Intel 82801I (ICH9) USB controller> on uhci5
ehci1: <Intel 82801I (ICH9) USB 2.0 controller> mem 0xfe7ff800-0xfe7ffbff irq 23 at device 29.7 on pci0
ehci1: [ITHREAD]
usbus7: EHCI version 1.0
usbus7: <Intel 82801I (ICH9) USB 2.0 controller> on ehci1
pcib5: <ACPI PCI-PCI bridge> at device 30.0 on pci0
pci5: <ACPI PCI bus> on pcib5
re0: <RealTek 8169SC/8110SC Single-chip Gigabit Ethernet> port 0xe800-0xe8ff mem 0xfebffc00-0xfebffcff irq 16 at device 4.0 on pci5
re0: Chip rev. 0x18000000
re0: MAC rev. 0x00000000
miibus1: <MII bus> on re0
rgephy0: <RTL8169S/8110S/8211B media interface> PHY 1 on miibus1
rgephy0:  10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, 1000baseT, 1000baseT-FDX, auto
re0: Ethernet address: 00:1d:60:a6:f0:50
re0: [FILTER]
isab0: <PCI-ISA bridge> at device 31.0 on pci0
isa0: <ISA bus> on isab0
atapci2: <Intel ICH9 SATA300 controller> port 0x9000-0x9007,0x8c00-0x8c03,0x8880-0x8887,0x8800-0x8803,0x8480-0x848f,0x8400-0x840f irq 22 at device 31.2 on pci0
atapci2: [ITHREAD]
ata5: <ATA channel 0> on atapci2
ata5: [ITHREAD]
ata6: <ATA channel 1> on atapci2
ata6: [ITHREAD]
ichsmb0: <SMBus controller> port 0x400-0x41f mem 0xfe7ff400-0xfe7ff4ff irq 18 at device 31.3 on pci0
ichsmb0: [ITHREAD]
smbus0: <System Management Bus> on ichsmb0
smb0: <SMBus generic I/O> on smbus0
atapci3: <Intel ICH9 SATA300 controller> port 0xa000-0xa007,0x9c00-0x9c03,0x9880-0x9887,0x9800-0x9803,0x9480-0x948f,0x9400-0x940f irq 22 at device 31.5 on pci0
atapci3: [ITHREAD]
ata7: <ATA channel 0> on atapci3
ata7: [ITHREAD]
ata8: <ATA channel 1> on atapci3
ata8: [ITHREAD]
acpi_button0: <Power Button> on acpi0
atrtc0: <AT realtime clock> port 0x70-0x71 irq 8 on acpi0
atkbdc0: <Keyboard controller (i8042)> port 0x60,0x64 irq 1 on acpi0
atkbd0: <AT Keyboard> irq 1 on atkbdc0
kbd0 at atkbd0
atkbd0: [GIANT-LOCKED]
atkbd0: [ITHREAD]
cpu0: <ACPI CPU> on acpi0
coretemp0: <CPU On-Die Thermal Sensors> on cpu0
cpu1: <ACPI CPU> on acpi0
coretemp1: <CPU On-Die Thermal Sensors> on cpu1
cpu2: <ACPI CPU> on acpi0
coretemp2: <CPU On-Die Thermal Sensors> on cpu2
cpu3: <ACPI CPU> on acpi0
coretemp3: <CPU On-Die Thermal Sensors> on cpu3
orm0: <ISA Option ROM> at iomem 0xc0000-0xcefff on isa0
sc0: <System console> at flags 0x100 on isa0
sc0: VGA <8 virtual consoles, flags=0x300>
vga0: <Generic ISA VGA> at port 0x3c0-0x3df iomem 0xa0000-0xbffff on isa0
fb0 at vga0
Timecounters tick every 1.333 msec
IPsec: Initialized Security Association Processing.
usbus0: 12Mbps Full Speed USB v1.0
usbus1: 12Mbps Full Speed USB v1.0
usbus2: 12Mbps Full Speed USB v1.0
usbus3: 480Mbps High Speed USB v2.0
usbus4: 12Mbps Full Speed USB v1.0
usbus5: 12Mbps Full Speed USB v1.0
usbus6: 12Mbps Full Speed USB v1.0
usbus7: 480Mbps High Speed USB v2.0
ugen0.1: <Intel> at usbus0
uhub0: <Intel UHCI root HUB, class 9/0, rev 1.00/1.00, addr 1> on usbus0
ugen1.1: <Intel> at usbus1
uhub1: <Intel UHCI root HUB, class 9/0, rev 1.00/1.00, addr 1> on usbus1
ugen2.1: <Intel> at usbus2
uhub2: <Intel UHCI root HUB, class 9/0, rev 1.00/1.00, addr 1> on usbus2
ugen3.1: <Intel> at usbus3
uhub3: <Intel EHCI root HUB, class 9/0, rev 2.00/1.00, addr 1> on usbus3
ugen4.1: <Intel> at usbus4
uhub4: <Intel UHCI root HUB, class 9/0, rev 1.00/1.00, addr 1> on usbus4
ugen5.1: <Intel> at usbus5
uhub5: <Intel UHCI root HUB, class 9/0, rev 1.00/1.00, addr 1> on usbus5
ugen6.1: <Intel> at usbus6
uhub6: <Intel UHCI root HUB, class 9/0, rev 1.00/1.00, addr 1> on usbus6
ugen7.1: <Intel> at usbus7
uhub7: <Intel EHCI root HUB, class 9/0, rev 2.00/1.00, addr 1> on usbus7
ad10: 238475MB <Hitachi HDT725025VLA380 V5DOA52A> at ata5-master SATA300
ad11: 476940MB <SAMSUNG HD501LJ CR100-11> at ata5-slave SATA300
GEOM: ad10s1: geometry does not match label (255h,63s != 16h,63s).
ad12: 610480MB <SAMSUNG HD642JJ 1AA01109> at ata6-master SATA300
GEOM: ad10s2: geometry does not match label (255h,63s != 16h,63s).
ad13: 381554MB <SAMSUNG HD403LJ CT100-11> at ata6-slave SATA300
uhub0: 2 ports with 2 removable, self powered
uhub1: 2 ports with 2 removable, self powered
uhub2: 2 ports with 2 removable, self powered
uhub4: 2 ports with 2 removable, self powered
uhub5: 2 ports with 2 removable, self powered
uhub6: 2 ports with 2 removable, self powered
uhub3: 6 ports with 6 removable, self powered
uhub7: 6 ports with 6 removable, self powered
acd0: DVDR <HL-DT-ST DVDRAM GSA-H62N/CL00> at ata8-master SATA150
hdac0: HDA Codec #0: ATI R6xx HDMI
pcm0: <HDA ATI R6xx HDMI PCM #0 Digital> at cad 0 nid 1 on hdac0
hdac1: HDA Codec #0: Analog Devices AD1988B
pcm1: <HDA Analog Devices AD1988B PCM #0 Analog> at cad 0 nid 1 on hdac1
pcm2: <HDA Analog Devices AD1988B PCM #1 Analog> at cad 0 nid 1 on hdac1
pcm3: <HDA Analog Devices AD1988B PCM #2 Digital> at cad 0 nid 1 on hdac1
acd0: FAILURE - INQUIRY ILLEGAL REQUEST asc=0x24 ascq=0x00 sks=0x40 0x00 0x01
acd0: FAILURE - INQUIRY ILLEGAL REQUEST asc=0x24 ascq=0x00 sks=0x40 0x00 0x01
SMP: AP CPU #1 Launched!
SMP: AP CPU #3 Launched!
SMP: AP CPU #2 Launched!
ugen6.2: <Logitech> at usbus6
ums0: <Logitech USB-PS/2 Optical Mouse, class 0/0, rev 2.00/27.20, addr 2> on usbus6
ums0: 8 buttons and [XYZ] coordinates
cd0 at ata2 bus 0 target 0 lun 0
cd0: <HL-DT-ST DVDRAM GSA-H62N CL00> Removable CD-ROM SCSI-0 device 
cd0: 3.300MB/s transfers
cd0: Attempt to query device size failed: NOT READY, Medium not present
Trying to mount root from ufs:/dev/ad10s1a
WARNING: / was not properly dismounted
WARNING: /compat was not properly dismounted
WARNING: /data was not properly dismounted
WARNING: /scratch was not properly dismounted
WARNING: /usr was not properly dismounted
WARNING: /usr/local was not properly dismounted
/usr/local: mount pending error: blocks 4 files 1
WARNING: /usr/obj was not properly dismounted
WARNING: /usr/ports was not properly dismounted
WARNING: /usr/src was not properly dismounted
WARNING: /var was not properly dismounted
/var: mount pending error: blocks 132 files 20
This module (opensolaris) contains code covered by the
Common Development and Distribution License (CDDL)
see http://opensolaris.org/os/licensing/opensolaris_license/
WARNING: ZFS is considered to be an experimental feature in FreeBSD.
ZFS filesystem version 13
ZFS storage pool version 13
pf: started
altq: started
msk0: link state changed to UP