FreeBSD 6.0 sudden kernel panic

[Lukasz Jaroszewski]

I did nothing special when suddenly my freebsd rebooted:

Jul 10 17:16:06 nietykalni savecore: reboot after panic: page fault
Jul 10 17:16:06 nietykalni savecore: writing core to vmcore.0

--------------------------------------------------------------------------
nietykalni# cat /var/crash/info.0
Dump header from device /dev/ad1s1b
   Architecture: i386
   Architecture Version: 2
   Dump Length: 267976704B (255 MB)
   Blocksize: 512
   Dumptime: Mon Jul 10 17:19:31 2006
   Hostname: nietykalni.org
   Magic: FreeBSD Kernel Dump
   Version String: FreeBSD 6.0-RELEASE #1: Tue Mar 14 10:40:21 CET 2006
     vandal at revival:/usr/obj/usr/src/sys/GENERIC-NIETYKALNI
   Panic String: page fault
   Dump Parity: 534305
   Bounds: 0
   Dump Status: good

-------------------------------------------------------------------------
nietykalni# kgdb kernel.debug /var/crash/vmcore.0

Unread portion of the kernel message buffer:


#0  doadump () at pcpu.h:165
165  __asm __volatile("movl %%fs:0,%0" : "=r" (td));
(kgdb) bt
#0  doadump () at pcpu.h:165
#1  0xc061f242 in boot (howto=260) at 
/usr/src/sys/kern/kern_shutdown.c:399
#2  0xc061f4d8 in panic (fmt=0xc07f4c2a "%s")
     at /usr/src/sys/kern/kern_shutdown.c:555
#3  0xc07b1f78 in trap_fatal (frame=0xd551cc18, eva=123)
     at /usr/src/sys/i386/i386/trap.c:831
#4  0xc07b1ce3 in trap_pfault (frame=0xd551cc18, usermode=0, eva=123)
     at /usr/src/sys/i386/i386/trap.c:742
#5  0xc07b1941 in trap (frame=
       {tf_fs = 8, tf_es = -1030815704, tf_ds = -1030815704, tf_edi = 
-1030797440, tf_esi = -1042154576, tf_ebp = -716059468, tf_isp = 
-716059580, tf_ebx = -1027664896,

tf_edx = -1030797440, tf_ecx = 4, tf_eax = 0, tf_trapno = 12, tf_err = 0, 
tf_eip = -1067455388, tf_cs = 32, tf_eflags = 66182, tf_esp = -1039158768, 
tf_ss = 0}) at

/usr/src/sys/i386/i386/trap.c:432
#6  0xc07a1a2a in calltrap () at /usr/src/sys/i386/i386/exception.s:139
#7  0xc05fec64 in closef (fp=0xc1826120, td=0xc28f4780)
     at /usr/src/sys/kern/kern_descrip.c:1876
#8  0xc05fc47d in close (td=0xc28f4780, uap=0x0)
     at /usr/src/sys/kern/kern_descrip.c:1004
#9  0xc07b228f in syscall (frame=
       {tf_fs = 59, tf_es = -1078001605, tf_ds = -1078001605, tf_edi = 0, 
tf_esi = 0, tf_ebp = -1077944344, tf_isp = -716059292, tf_ebx = 134934528, 
tf_edx = 0, tf_ecx =

0, tf_eax = 6, tf_trapno = 12, tf_err = 2, tf_eip = 144033747, tf_cs = 
---Type <return> to continue, or q <return> to quit---
51, tf_eflags = 662, tf_esp = -1077944372, tf_ss = 59})
     at /usr/src/sys/i386/i386/trap.c:976
#10 0xc07a1a7f in Xint0x80_syscall () at 
/usr/src/sys/i386/i386/exception.s:200
#11 0x00000033 in ?? ()
Previous frame inner to this frame (corrupt stack?)
(...)
(kgdb) up
#4  0xc07b1ce3 in trap_pfault (frame=0xd551cc18, usermode=0, eva=123)
     at /usr/src/sys/i386/i386/trap.c:742
742   trap_fatal(frame, eva);
(kgdb)  p p->p_comm
$1 = "screen", '\0' <repeats 13 times>
(...)
(kgdb) up
#7  0xc05fec64 in closef (fp=0xc1826120, td=0xc28f4780)
     at /usr/src/sys/kern/kern_descrip.c:1876
1876   vfslocked = VFS_LOCK_GIANT(vp->v_mount);
Current language:  auto; currently c
(kgdb) p vp
$2 = (struct vnode *) 0xc1e1fbb0
(kgdb) p vp-v_mount
No symbol "v_mount" in current context.
(kgdb) p vp->v_mount
$3 = (struct mount *) 0x0
(kgdb)
(...)