If I type 'shutdown -r now' it will panic

_panic
_trap
_vnode_pager_umount(0)
_reboot_sync(37,ffe3f80,dfffe2c,3bc48,14584)
_reboot2(0,0,ffe3f44,e0128e8,0)
_boot(0,0,ffe3fa0,e079342,e556c00)
_reboot(e556c00,ffe3f80,ffe3f78)
_syscall(0)
_trap0()

Mar 29 13:55:30 charon shutdown: reboot by root: 
Mar 29 13:55:35 charon syslogd: exiting on signal 15
Mar 29 14:03:59 charon /netbsd: syncing disks... trap type=0, code=0x145, v=0xdeadbef3
Mar 29 14:03:59 charon /netbsd: kernel: Bus error trap
Mar 29 14:03:59 charon /netbsd: pid = 105, pc = 0E06BCE8, ps = 2308, sfc = 0001, dfc = 0001
Mar 29 14:04:00 charon /netbsd: Registers:
Mar 29 14:04:00 charon /netbsd:              0        1        2        3        4        5        6        7
Mar 29 14:04:02 charon /netbsd: dreg: 00000000 00000002 DEADBEEF 00000000 00000064 00000000 00000000 00000007
Mar 29 14:04:03 charon /netbsd: areg: DEADBEEF 0E566280 0E572900 0E556C00 00000004 0E0A3540 0FFE3EE8 0DFFFDE8
Mar 29 14:04:03 charon /netbsd: 
Mar 29 14:04:04 charon /netbsd: Kernel stack (0FFE3DE0):
Mar 29 14:04:05 charon /netbsd: FE3DE0: 0E078F26 0FFE3E34 00000080 DEADBEEF 00000000 00000064 00000000 00000000
Mar 29 14:04:05 charon /netbsd: FE3E00: 00000007 0E572900 0E556C00 00000004 0E0A3540 0E075F0A 0E11BAB0 00000000
Mar 29 14:04:07 charon /netbsd: FE3E20: 0FFE3EE8 0E004864 00000000 00000145 DEADBEF3 00000000 00000002 DEADBEEF
Mar 29 14:04:07 charon /netbsd: FE3E40: 00000000 00000064 00000000 00000000 00000007 DEADBEEF 0E566280 0E572900
Mar 29 14:04:08 charon /netbsd: FE3E60: 0E556C00 00000004 0E0A3540 0FFE3EE8 0DFFFDE8 00000000 23080E06 BCE8B008
Mar 29 14:04:08 charon /netbsd: FE3E80: 0E2C0145 4A836706 DEADBEF3 DEADBEF3 DEADBEEF 24680004 0E06BCF0 0E06BCEE
Mar 29 14:04:09 charon /netbsd: FE3EA0: 0E06BCEC FFFFFFFF 0004FF0B 000F1486 DEADBEEF 0E535480 0E08C358 00000E08
Mar 29 14:04:09 charon /netbsd: FE3EC0: A0200000 DEADBEF3 00000000 0E572900 0FFE3ECC 00000000 00000000 0FFE3F80
Mar 29 14:04:10 charon /netbsd: FE3EE0: 0E08C358 0E572900 0FFE3F04 0E0737B4 00000000 00000000 00000000 00000064
Mar 29 14:04:10 charon /netbsd: FE3F00: 0FFE3F80 0FFE3F24 0E0738A4 00000037 0FFE3F80 0DFFFE2C 0003BC48 00014584
Mar 29 14:04:11 charon /netbsd: FE3F20: 0DFFFFE6 0FFE3F34 0E07393E 00000000 00000000 0FFE3F44 0E0128E8 00000000
Mar 29 14:04:12 charon /netbsd: FE3F40: 00000000 0FFE3FA0 0E079342 0E556C00 0FFE3F80 0FFE3F78 00000002 00000000
Mar 29 14:04:13 charon /netbsd: FE3F60: 00000000 00012A8A 0DFFFE2C 0003BC48 00014584 00002B7E 00000000 FFFFFFFF
Mar 29 14:04:13 charon /netbsd: FE3F80: 00000000 0003BC48 00014584 00014584 00000000 00000064 0DFFFDCC 0E0045EA
Mar 29 14:04:13 charon /netbsd: FE3FA0: 0DFFFE08 0E0049AC 00000000 00000000 FFFFFFFF 00000002 00000000 00000000
Mar 29 14:04:14 charon /netbsd: FE3FC0: 00000000 00000000 00000007 0DFFFDD4 0DFFFDDC 00012A8A 0DFFFE2C 0003BC48
Mar 29 14:04:16 charon /netbsd: panic: Bus error
Mar 29 14:04:17 charon /netbsd: dumping not supported yet :)
Mar 29 14:04:17 charon /netbsd: Kernel rebooting...