periodical crash 6.1-REL

[dawnshade]

Hi all.

I have periodically crashes 6.1-RELEASE running on Intel MB S875WP1

in messages i see: May 31 06:14:50 mail savecore: reboot after panic: page 
fault

i installed debug kernel and got a core, but can't understand what happens. 
results of backtrace :


mail# kgdb /boot/kernel/kernel vmcore.4
[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".
(no debugging symbols found)...Attempt to extract a component of a value that 
is not a structure pointer.
(kgdb) bt
#0  0xc04bd73c in doadump ()
#1  0xc04bdd8d in boot ()
#2  0xc04be13e in panic ()
#3  0xc060c155 in trap_fatal ()
#4  0xc060be49 in trap_pfault ()
#5  0xc060ba2f in trap ()
#6  0xc05f6f6a in calltrap ()
#7  0xc056a0d1 in ip_ctloutput ()
#8  0xc0579d7b in tcp_ctloutput ()
#9  0xc05033bc in sogetopt ()
#10 0xc05092df in kern_getsockopt ()
#11 0xc05091ce in getsockopt ()
#12 0xc060c53c in syscall ()
#13 0xc05f6fbf in Xint0x80_syscall ()
#14 0x00000033 in ?? ()
Previous frame inner to this frame (corrupt stack?)
(kgdb)                    


dmesg:

Copyright (c) 1992-2006 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 6.1-RELEASE #0: Sat May 27 22:54:46 MSD 2006
    root at mail.*.ru:/usr/src/sys/i386/compile/mail_kern_6
MPTable: < Canterwood-P>
Timecounter "i8254" frequency 1193182 Hz quality 0
CPU: Intel(R) Pentium(R) 4 CPU 2.80GHz (2793.01-MHz 686-class CPU)
  Origin = "GenuineIntel"  Id = 0xf25  Stepping = 5
  
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=0x4400<CNTX-ID,<b14>>
  Logical CPUs per core: 2
real memory  = 2146631680 (2047 MB)
avail memory = 2097582080 (2000 MB)
ioapic0: Assuming intbase of 0
ioapic0 <Version 2.0> irqs 0-23 on motherboard
cpu0 on motherboard
pcib0: <MPTable Host-PCI bridge> pcibus 0 on motherboard
pci0: <PCI bus> on pcib0
pcib1: <PCI-PCI bridge> at device 1.0 on pci0
pci1: <PCI bus> on pcib1
pcib2: <MPTable PCI-PCI bridge> at device 3.0 on pci0
pci2: <PCI bus> on pcib2
em0: <Intel(R) PRO/1000 Network Connection Version - 3.2.18> port 
0xbc00-0xbc1f mem 0xfc9e0000-0xfc9fffff irq 18 at device 1.0 on pci2
em0: Ethernet address: 00:0c:f1:e4:26:5b
pci0: <serial bus, USB> at device 29.0 (no driver attached)
pci0: <serial bus, USB> at device 29.1 (no driver attached)
pci0: <serial bus, USB> at device 29.2 (no driver attached)
pci0: <serial bus, USB> at device 29.3 (no driver attached)
pcib3: <MPTable PCI-PCI bridge> at device 30.0 on pci0
pci3: <PCI bus> on pcib3
pci3: <display, VGA> at device 6.0 (no driver attached)
pci3: <network, ethernet> at device 8.0 (no driver attached)
isab0: <PCI-ISA bridge> at device 31.0 on pci0
isa0: <ISA bus> on isab0
atapci0: <Intel ICH5 UDMA100 controller> port 
0x1f0-0x1f7,0x3f6,0x170-0x177,0x376,0xffa0-0xffaf at device 31.1 on pci0
ata0: <ATA channel 0> on atapci0
ata1: <ATA channel 1> on atapci0
pci0: <serial bus, SMBus> at device 31.3 (no driver attached)
pmtimer0 on isa0
orm0: <ISA Option ROM> at iomem 0xc0000-0xc7fff 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>
sio0: configured irq 4 not in bitmap of probed irqs 0
sio0: port may not be enabled
sio0 at port 0x3f8-0x3ff irq 4 flags 0x10 on isa0
sio0: type 8250 or not responding
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
unknown: <PNP0303> can't assign resources (port)
unknown: <INT0800> can't assign resources (memory)
Timecounter "TSC" frequency 2793010524 Hz quality 800
Timecounters tick every 1.000 msec
ipfw2 (+ipv6) initialized, divert loadable, rule-based forwarding disabled, 
default to accept, logging unlimited
ad0: 190782MB <Seagate ST3200822A 3.01> at ata0-master UDMA100
acd0: CDROM <ASUS CD-S520/A4/1.2> at ata1-master UDMA33

This dmesg w/o ACPI, i tried running with and got the same results.
HTT disabled by default.
Can anybody interpreter resuls of backtrace?

thx.