trap 12 during boot

[Jean-Marc Zucconi]

>>>>> Matthew Dillon writes:

 > :This occured with a world/kernel from yesterday sources:
 > :
 > :Booting [/kernel]...               
 > :ACPI autoload failed - no such file or directory
 > :...

 >     If it happens again get a stack backtrace using 'trace'.  If you have a
 >     kernel core we can work from that, too.

The trace does not help here:
db> trace


Fatal trap 12: page fault while in kernel mode
mp_lock = 00000000; cpuid = 0; lapic.id = 01000000
fault virtual address   = 0x8758b53
fault code              = supervisor read, page not present
instruction pointer     = 0x8:0xc02f0a50
stack pointer           = 0x10:0xc048eac8
frame pointer           = 0x10:0xc048eacc
code segment            = base 0x0, limit 0xfffff, type 0x1b
                        = DPL 0, pres 1, def32 1, gran 1
processor eflags        = resume, IOPL = 0
current process         = 0 (swapper)
current thread          = pri 12 
interrupt mask          = net tty bio cam  <- SMP: XXX
kernel: type 12 trap, code=0
db> 

Here the IP is into the debugger:
     c02f004c T db_disasm
     c02f07a8 T kdb_trap
     c02f0a34 T db_read_bytes
     c02f0a6c T db_write_bytes

Jean-Marc

-- 
Jean-Marc Zucconi -- PGP Key: finger jmz at xxxxxxxxxxx [KeyID: 400B38E9]