panic: device_set_ivars(NULL, ...) (was: fatal trap 12 when booting without ACPI)

I recompiled the kernel with all invariants and ddb enabled, which
seems to catch the problem already while setting some invariants.
See further down.

Without invariants or ddb, I get the following:

pcib5: <ServerWorks NB6635 3.0LE host to PCI bridge> at pcibus 5 on motherboard

Fatal trap 12: page fault while in kernel mode
fault virtual address   = 0x44
fault code              = supervisor write, age not present
instruction pointer     = 0x8:0xc04f0919
stack pointer           = 0x10:0xc0821c34
frame pointer           = 0x10:0xc0821c34
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 (swapper)
trap number             = 12
panic: page fault
at line 815 in file /usr/src/sys/i386/i386/trap.c
Uptime: 1s


With invariants and ddb in I get:

pcib5: <ServerWorks NB6635 3.0LE host to PCI bridge> at pcibus 5 on motherboard
panic: device_set_invars(NULL, ...)
at line 1353 in file ../../../kern/subr_bus.c
Debugger("panic")
Stopped at      Debugger+0x54:  xchgl    %ebx,in_Debugger.0
db>


``db> where'' results in (truncated ``[...]'' alot of information):

Debugger[...]
__panic[...]
device_set_invars[...]
legacy_add_child[...]
legacy_pcib_attach[...]
[...]

Please tell me what data You need (like full where with argument
values and addresses).

Regards, Robert S.