Can not boot kernel from Mar 10 07:22 UTC

GDB: no debug ports present
KDB: debugger backends: ddb
KDB: current backend: ddb
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 7.0-CURRENT #1: Fri Mar 10 08:43:30 CET 2006
    pho_at_current.osted.lan:/usr/src/sys/i386/compile/PHO
WARNING: WITNESS option enabled, expect reduced performance.
ACPI APIC Table: <A M I  OEMAPIC >
Timecounter "i8254" frequency 1193182 Hz quality 0
CPU: Intel(R) Celeron(R) CPU 1.80GHz (1799.14-MHz 686-class CPU)
  Origin = "GenuineIntel"  Id = 0xf13  Stepping = 3
  Features=0x3febfbff<FPU,VME,DE,...,DTS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM>
real memory  = 267583488 (255 MB)
avail memory = 252137472 (240 MB)
:
ad0: 76319MB <Seagate ST380011A 3.06> at ata0-master UDMA100
acd0: DMA limited to UDMA33, controller found non-ATA66 cable
acd0: CDROM <SONY CD-ROM CDU5261/C200SNS> at ata1-master UDMA33
Trying to mount root from ufs:/dev/ad0s1a


Fatal trap 12: page fault while in kernel mode
cpuid = 0; apic id = 00
fault virtual address	= 0x2
fault code		= supervisor write, page not present
instruction pointer	= 0x20:0xc07887f7
stack pointer	        = 0x28:0xcbf617d4
frame pointer	        = 0x28:0xcbf618bc
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		= 1 (swapper)
[thread pid 1 tid 100007 ]
Stopped at      ffs_balloc_ufs2+0x8f:   movl    $0,0(%edi)
db> where
Tracing pid 1 tid 100007 td 0xc21bd360
ffs_balloc_ufs2(c23f3a28,0,0,0,cbf618f8) at ffs_balloc_ufs2+0x8f
ufsdirhash_build(c23f9dec) at ufsdirhash_build+0x3c4
ufs_lookup(cbf619f8,c23f3a28,cbf61c28,cbf61a34,c06b3af2) at ufs_lookup+0xf9
VOP_CACHEDLOOKUP_APV(c093a3e0,cbf619f8) at VOP_CACHEDLOOKUP_APV+0x9b
vfs_cache_lookup(cbf61a94,c23f3a28,0,cbf61ab0,c06b7ce6) at vfs_cache_lookup+0xb2
VOP_LOOKUP_APV(c093a3e0,cbf61a94) at VOP_LOOKUP_APV+0x87
lookup(cbf61c00,3,0,c21bd360,c068a77d) at lookup+0x402
namei(cbf61c00,9,0,0,0) at namei+0x382
do_execve(c21bd360,cbf61c90,0,cbf61c90,bfbffff2) at do_execve+0x159
kern_execve(c21bd360,cbf61c90,0) at kern_execve+0x7c
execve(c21bd360,cbf61cf0,bfbfffe4,bfbffff2,bfbfffe8,bfbffffd,...) at execve+0x2f
start_init(0,cbf61d38) at start_init+0x20b
fork_exit(c063bc9c,0,cbf61d38) at fork_exit+0xa4
fork_trampoline() at fork_trampoline+0x8
--- trap 0x1, eip = 0, esp = 0xcbf61d6c, ebp = 0 ---
db> reset

(kgdb) l *0xc07887f7
0xc07887f7 is in ffs_balloc_ufs2 (../../../ufs/ffs/ffs_balloc.c:478).
473             ump = ip->i_ump;
474             lbn = lblkno(fs, startoffset);
475             size = blkoff(fs, startoffset) + size;
476             if (size > fs->fs_bsize)
477                     panic("ffs_balloc_ufs2: blk too big");
478             *bpp = NULL;
479             if (lbn < 0)
480                     return (EFBIG);
481
482             /*


This is GENERIC with:

include GENERIC
ident          PHO-GENERIC
options        BREAK_TO_DEBUGGER
options        DEBUG_VFS_LOCKS

-- 
Peter Holm