[root@paprika] /usr/obj/usr/src/sys/UP# kgdb -n 9                                                                  [102]
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Unread portion of the kernel message buffer:
panic: snapacct_ufs2: bad block
Uptime: 15m43s
Physical memory: 1014 MB
Dumping 99 MB: 84 68 52 36 20 4

Reading symbols from /boot/kernel/acpi.ko...Reading symbols from /boot/kernel/acpi.ko.symbols...done.
done.
Loaded symbols for /boot/kernel/acpi.ko
#0  doadump () at pcpu.h:196
196             __asm __volatile("movl %%fs:0,%0" : "=r" (td));
(kgdb) bt
#0  doadump () at pcpu.h:196
#1  0xc0571a1a in boot (howto=260) at /usr/src/sys/kern/kern_shutdown.c:418
#2  0xc0571c54 in panic (fmt=Variable "fmt" is not available.
) at /usr/src/sys/kern/kern_shutdown.c:574
#3  0xc06c007a in snapacct_ufs2 (vp=0xc4388cf0, oldblkp=0xc43ebf48, lastblkp=0xc43ee000, fs=0xc3e23800, lblkno=2007052,
    expungetype=2) at /usr/src/sys/ufs/ffs/ffs_snapshot.c:1481
#4  0xc06bf6ab in indiracct_ufs2 (snapvp=0xc4388cf0, cancelvp=0xc3e29e04, level=0, blkno=11294696, lbn=-2007052,
    rlbn=2007052, remblks=9273, blksperindir=1, fs=0xc3e23800, acctfunc=0xc06bff31 <snapacct_ufs2>, expungetype=2)
    at /usr/src/sys/ufs/ffs/ffs_snapshot.c:1396
#5  0xc06bf5fc in indiracct_ufs2 (snapvp=0xc4388cf0, cancelvp=0xc3e29e04, level=0, blkno=11670776, lbn=Unhandled dwarf expression opcode 0x93
)
    at /usr/src/sys/ufs/ffs/ffs_snapshot.c:1406
#6  0xc06c05a3 in expunge_ufs2 (snapvp=0xc4388cf0, cancelip=0xc3e14b80, fs=0xc3e23800,
    acctfunc=0xc06bff31 <snapacct_ufs2>, expungetype=2) at /usr/src/sys/ufs/ffs/ffs_snapshot.c:1328
#7  0xc06c3c2a in ffs_snapshot (mp=0xc3dd9864, snapfile=0xc416bb40 "/jail/bender/.snap/fsck_snapshot")
    at /usr/src/sys/ufs/ffs/ffs_snapshot.c:711
#8  0xc06d3bfa in ffs_mount (mp=0xc3dd9864, td=0xc437e000) at /usr/src/sys/ufs/ffs/ffs_vfsops.c:337
#9  0xc05e1a04 in vfs_donmount (td=0xc437e000, fsflags=18944000, fsoptions=0xc3e33180)
    at /usr/src/sys/kern/vfs_mount.c:1014
#10 0xc05e2c07 in nmount (td=0xc437e000, uap=0xe65b4cfc) at /usr/src/sys/kern/vfs_mount.c:415
#11 0xc073408b in syscall (frame=0xe65b4d38) at /usr/src/sys/i386/i386/trap.c:1090
#12 0xc07237f0 in Xint0x80_syscall () at /usr/src/sys/i386/i386/exception.s:255
#13 0x00000033 in ?? ()
Previous frame inner to this frame (corrupt stack?)
(kgdb)