> kgdb kernel.debug /var/crash/vmcore.0
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Unread portion of the kernel message buffer:


Fatal trap 12: page fault while in kernel mode
cpuid = 0; apic id = 00
fault virtual address = 0x0
fault code = supervisor write, page not present
instruction pointer = 0x20:0xc05957dd
stack pointer = 0x28:0xe92ee800
frame pointer = 0x28:0xe92ee828
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 = 1609 (initial thread)
trap number = 12
panic: page fault
cpuid = 0
Uptime: 4h17m1s
Physical memory: 2960 MB
Dumping 142 MB: 127 111 95 79 63 47 31 15

Reading symbols from /boot/kernel/snd_hda.ko...Reading symbols from /boot/kernel/snd_hda.ko.symbols...done.
done.
Loaded symbols for /boot/kernel/snd_hda.ko
Reading symbols from /boot/kernel/sound.ko...Reading symbols from /boot/kernel/sound.ko.symbols...done.
done.
Loaded symbols for /boot/kernel/sound.ko
Reading symbols from /boot/kernel/if_iwn.ko...done.
Loaded symbols for /boot/kernel/if_iwn.ko
Reading symbols from /boot/kernel/iwn5000fw.ko...done.
Loaded symbols for /boot/kernel/iwn5000fw.ko
Reading symbols from /boot/modules/vboxdrv.ko...done.
Loaded symbols for /boot/modules/vboxdrv.ko
Reading symbols from /boot/kernel/i915.ko...Reading symbols from /boot/kernel/i915.ko.symbols...done.
done.
Loaded symbols for /boot/kernel/i915.ko
Reading symbols from /boot/kernel/drm.ko...Reading symbols from /boot/kernel/drm.ko.symbols...done.
done.
Loaded symbols for /boot/kernel/drm.ko
#0 doadump () at pcpu.h:246
246 __asm __volatile("movl %%fs:0,%0" : "=r" (td));
(kgdb) backtrace
#0 doadump () at pcpu.h:246
#1 0xc05d8507 in boot (howto=260) at ../../../kern/kern_shutdown.c:416
#2 0xc05d87f9 in panic (fmt=Variable "fmt" is not available.
) at ../../../kern/kern_shutdown.c:579
#3 0xc088bcdc in trap_fatal (frame=0xe92ee7c0, eva=0) at ../../../i386/i386/trap.c:933
#4 0xc088bf40 in trap_pfault (frame=0xe92ee7c0, usermode=0, eva=0) at ../../../i386/i386/trap.c:846
#5 0xc088c8f9 in trap (frame=0xe92ee7c0) at ../../../i386/i386/trap.c:528
#6 0xc086faeb in calltrap () at ../../../i386/i386/exception.s:165
#7 0xc05957dd in clone_create (cdp=0xc09bee84, csw=0xc0971cc0, up=0xe92ee84c, dp=0xe92ee8dc, extra=0) at ../../../kern/kern_conf.c:1017
#8 0xc0866582 in apm_clone (arg=0x0, cred=0xc6efb700, name=0xe92ee91c "apm", namelen=3, dev=0xe92ee8dc) at ../../../i386/acpica/acpi_machdep.c:237
#9 0xc055f6e5 in devfs_lookup (ap=0xe92ee990) at ../../../fs/devfs/devfs_vnops.c:811
#10 0xc0898926 in VOP_LOOKUP_APV (vop=0xc0949b00, a=0xe92ee990) at vnode_if.c:123
#11 0xc0655bce in lookup (ndp=0xe92eeba4) at vnode_if.h:54
#12 0xc0656c0b in namei (ndp=0xe92eeba4) at ../../../kern/vfs_lookup.c:264
#13 0xc066e883 in vn_open_cred (ndp=0xe92eeba4, flagp=0xe92eec5c, cmode=0, vn_open_flags=Variable "vn_open_flags" is not available.
) at ../../../kern/vfs_vnops.c:188
#14 0xc066eb8b in vn_open (ndp=0xe92eeba4, flagp=0xe92eec5c, cmode=0, fp=0xc6bce310) at ../../../kern/vfs_vnops.c:94
#15 0xc066d40f in kern_openat (td=0xc6f42240, fd=-100, path=0x8075d80 , pathseg=UIO_USERSPACE, flags=1, mode=0) at ../../../kern/vfs_syscalls.c:1084
#16 0xc066d915 in kern_open (td=0xc6f42240, path=0x8075d80 , pathseg=UIO_USERSPACE, flags=0, mode=0) at ../../../kern/vfs_syscalls.c:1038
#17 0xc066d950 in open (td=0xc6f42240, uap=0xe92eecf8) at ../../../kern/vfs_syscalls.c:1014
#18 0xc088c285 in syscall (frame=0xe92eed38) at ../../../i386/i386/trap.c:1073
#19 0xc086fb50 in Xint0x80_syscall () at ../../../i386/i386/exception.s:261
#20 0x00000033 in ?? ()
Previous frame inner to this frame (corrupt stack?)
(kgdb) list *0xc0713860
0xc0713860 is in sctp_med_chunk_output (../../../netinet/sctp_output.c:8318).
8313 }
8314 SCTPDBG(SCTP_DEBUG_OUTPUT3, "Gak send error %d\n", error);
8315 if (hbflag) {
8316 if (*now_filled == 0) {
8317 (void)SCTP_GETTIME_TIMEVAL(&net->last_sent_time);
8318 *now_filled = 1;
8319 *now = net->last_sent_time;
8320 } else {
8321 net->last_sent_time = *now;
8322 }
(kgdb)