LOR/trap

JFYI, just got this.  Interestingly enough, the machine is still running :)
I have never seen this kind of traps before, so I don't know how to debug
further.

WARNING: / was not properly dismounted
module_register: module if_tun already exists!
Module if_tun failed to register: 17
can't re-use a leaf (if_tun_debug)!
lock order reversal
 1st 0xc3827948 vm object (vm object) _at_
/usr/src/sys/vm/swap_pager.c:1313
 2nd 0xc0900580 swap_pager swhash (swap_pager swhash) _at_
/usr/src/sys/vm/swap_pager.c:1803
 3rd 0xc103f8c4 vm object (vm object) _at_ /usr/src/sys/vm/uma_core.c:886
Stack backtrace:
backtrace(0,1,c08cef20,c08d00f0,c0838f9c) at backtrace+0x12
witness_checkorder(c103f8c4,9,c07f2153,376) at witness_checkorder+0x593
_mtx_lock_flags(c103f8c4,0,c07f2153,376,c2c418d4) at
_mtx_lock_flags+0x67
obj_alloc(c2c418c0,1000,cdb1ca3b,101,c2c418d4) at obj_alloc+0x31
slab_zalloc(c2c418c0,1,c2c418c0,c2c418d4,1) at slab_zalloc+0x82
uma_zone_slab(c2c418c0,1,c2c418d4,0,c07f2153,68f) at uma_zone_slab+0xb5
uma_zalloc_internal(c2c418c0,0,1,c2c418d4,0) at uma_zalloc_internal+0x28
uma_zalloc_arg(c2c418c0,0,1) at uma_zalloc_arg+0x2f8
swp_pager_meta_build(c3827948,38,0,2,0) at swp_pager_meta_build+0x108
swap_pager_putpages(c3827948,cdb1cc00,1,0,cdb1cb70) at
swap_pager_putpages+0x2b4
default_pager_putpages(c3827948,cdb1cc00,1,0,cdb1cb70) at
default_pager_putpages+0x18
vm_pageout_flush(cdb1cc00,1,0,8,c14fd7e0) at vm_pageout_flush+0x11e
vm_pageout_clean(c13372f8) at vm_pageout_clean+0x2a5
vm_pageout_scan(0) at vm_pageout_scan+0x54b
vm_pageout(0,cdb1cd48,0,c07320cc,0) at vm_pageout+0x2d2
fork_exit(c07320cc,0,cdb1cd48) at fork_exit+0xa8
fork_trampoline() at fork_trampoline+0x8
--- trap 0x1, eip = 0, esp = 0xcdb1cd7c, ebp = 0 ---

FreeBSD mobile.kawo2.rwth-aachen.de 5.2-CURRENT FreeBSD 5.2-CURRENT #1: Tue Mar 16 14:00:22 CET 2004
alex_at_mobile.kawo2.rwth-aachen.de:/usr/obj/usr/src/sys/MOBILE  i386

Alex