Panic on boot on Lenovo ThinkCentre, before copyright message appears

[Antony Mawer]

I've been having trouble getting 6.x, 7.x and 8.0 to boot on a Lenovo 
ThinkCentre M-series, model 6081 AG1. The system panics on boot, what 
seems to be as soon as it goes to boot the kernel (it loads the kernel 
and modules like acpi.ko fine)...

System is running the latest BIOS (2KRT50AUS) from 22 July 2008; we have 
successfully booted Windows and Linux on the same system, and it has 
survived several hours of memtest'ing.

The panic (manually transcribed, so I hope I haven't made any typos) as 
seen from the 200807/i386 snapshot CD:


/boot/kernel/acpi.ko text=0x54624 data=0x2640+0x182c 
syms=0x4+0x8b70+0x4+0xbe09]
GDB: no debug ports present
KDB: debugger backends: ddb
KDB: current backend: ddb



Fatal trap 12: page fault while in kernel mode
cpuid = 0; apic id = 00
fatal virtual address   = 0xf000ff53
fault code              = supervisor read, page not present
instruction pointer     = 0x20:0xf000ff53
stack pointer           = 0x28:0xc1421f0c
frame pointer           = 0x28:0xc1421f9c
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 ()
[thread pid 0 tid 0 ]
Stopped at      0xf000ff53:     *** error reading from address f000ff53 ***
db> bt
Tracing pid 0 tid 0 td 0xc0c837c0
trap(c1421fa8) at trap+0x66f
calltrap() at calltrap+0x6
--- trap 0x9, eip = 0x3fbb, esp = 0xfd2, ebp = 0 ---
db> sh reg
cs                0x20
ds                0x28
es                0x28
fs                 0x8
ss                0x28
eax         0xf000ff53
ecx                0x9
edx                0xa
ebx                0x9
esp         0xc1421f0c
ebp         0xc1421f9c
esi         0xc1421fa8
edi         0xc0c837c0   thread0
eip         0xf000ff53
efl            0x10286
0xf000ff53:     *** error reading from address f000ff53 ***
db>



Is there any additional information I can provide from the DDB prompt 
that may help tracking down why this machine is unable to boot (I have 
included the output from backtrace above, but it does not appear to help 
much...)?

Cheers
Antony