Page fault in kernel mode, 6.0-RELEASE

[Guido Van Hoecke]

I am fairly new at FreeBSD. I installed a 'beastie' server with 

FreeBSD 6.0-RELEASE #0: Thu Nov  3 09:36:13 UTC 2005
    root at x64.samsco.home:/usr/obj/usr/src/sys/GENERIC

but it traps immediately after the boot menu with following output
immediately after the boot menu:

/boot/kernel/acpi.ko text=0x40c2c data=0x2160+0x1090 \
syms=[0x4+0x7810+0x4+0xa292]

Fatal trap 12: page fault while in kernel mode
fault virtual address   = 0x8
fault code              = supervisor read, page not present
instruction pointer     = 0x20:0xc079abb9
stack pointer           = 0x28:0xc0c20d4c
frame pointer           = 0x28:0xc0c20d58
code segment            = base 0x0, limit 0xfffff, type 0x1b
                        = DPL 0, pres 1, def32 1, gran 1
processor eflags        = interrupt enabled, resume, IOPL = 0
current process         = 0 ()
trap number             = 12
panic: page fault
Uptime: 1s

Note that the /boot/kernel/acpi.ko line is absent if I boot with acpi
disabled (menu option 2). But the trap info is not affected by slecting
that boot option.

This is a 1.7 Ghz P4 with 1Gb mry and a fast 250Gb drive fully
dedicated (using normal partition scheme, not 'dangourously
dedicated') to FreeBSD. It has an MSI 845 Pro2 motherboard.

I had this trap during the first install yesterday. So I restarted the
installation and all went fine. After the installation, I rebooted
beastie and had no problems. I was able to work on it locally as well
as over an ssh connection to it.

Some time late at night, beastie trapped as reported above. Since
then, it never got beyond this trap. That's it. Full stop!

I looked into the BIOS setup, trying to change default settings that
might influence the kernel, such as disabling APIC mode. No success.

I booted the machine from a memtest86 CD and had it testing the memory
during several hours. No errors were detected. I ran all test programs
I could find (a.o. using Hiren's boot cd), and didn't find any
problems with the PC.

Still, I am pretty sure there must be a problem with that PC. Booting
from the FreeBSD-6.0-RC1 or FreeBSD-5.4R cd's causes the same trap at
the same point. Well, right now they just reboot after the menu. And
so does FreeSBIE 1.1 (FreeBSD 5.3 Live CD)

I've been further experimenting with the BIOS, I have upgraded it to
the latest version available from MSI.

Bottom line is that now it does not trap anymore. After the boot menu,
it goes a bit furthre. It shows the CopyRight and Release info and
reboots automaticlally without any further info.

Is there anything I can do to get more info about the reason for this
frustrating behaviour?

I do hope that more kernel-knowledgeable people will be able to point
my nose in the proper direction, given the consistant moment where the
error occurs. This is so frustrating, and I almost do feel ashame to
dump this onto the FreeBSD community, but I am desperate to get this
server installed and running!

Guido.