Kernel spewing errors/warnings on 7.0-CURRENT

After restarting my FreeBSD-CURRENT workstation, shortly after I  
logged in, and shortly before bg_fsck had completely (power outage  
last night) I got the following set of messages spewed to ttyv0 :

Aug  3 16:19:17 workstation kernel: lock order reversal
Aug  3 16:19:17 workstation kernel: 1st 0xc097ab20 UMA lock (UMA  
lock) _at_ /usr/src/sys/vm/uma_core.c:1491
Aug  3 16:19:17 workstation kernel: 2nd 0xc1060144 system map (system  
map) _at_ /usr/src/sys/vm/vm_map.c:2317
Aug  3 16:19:17 workstation kernel: KDB: stack backtrace:
Aug  3 16:19:17 workstation kernel: kdb_backtrace 
(0,ffffffff,c092fc38,c092fd78,c08ba624) at kdb_backtrace+0x29
Aug  3 16:19:17 workstation kernel: witness_checkorder 
(c1060144,9,c0870d80,90d) at witness_checkorder+0x564
Aug  3 16:19:17 workstation kernel: _mtx_lock_flags 
(c1060144,0,c0870d80,90d) at _mtx_lock_flags+0x5b
Aug  3 16:19:17 workstation kernel: _vm_map_lock 
(c10600c0,c0870d80,90d) at _vm_map_lock+0x26
Aug  3 16:19:17 workstation kernel: vm_map_remove 
(c10600c0,c1d0a000,c1d0b000,d56ecc08,c077e4e1) at vm_map_remove+0x1f
Aug  3 16:19:17 workstation kernel: kmem_free 
(c10600c0,c1d0a000,1000,d56ecc38,c077de8e) at kmem_free+0x25
Aug  3 16:19:17 workstation kernel: page_free(c1d0a000,1000,2) at  
page_free+0x29
Aug  3 16:19:17 workstation kernel: zone_drain(c104a960) at zone_drain 
+0x26a
Aug  3 16:19:17 workstation kernel: zone_foreach 
(c077dc24,d56eccec,c078fcaf,c1a3d900,d56ecc74) at zone_foreach+0x37
Aug  3 16:19:17 workstation kernel: uma_reclaim 
(c1a3d900,d56ecc74,0,c0926260,d56ecc80) at uma_reclaim+0x12
Aug  3 16:19:17 workstation kernel: vm_pageout_scan 
(0,c097af80,0,c087226d,5c3) at vm_pageout_scan+0x103
Aug  3 16:19:17 workstation kernel: vm_pageout 
(0,d56ecd38,0,c0790a68,0) at vm_pageout+0x2c3
Aug  3 16:19:17 workstation kernel: fork_exit(c0790a68,0,d56ecd38) at  
fork_exit+0xa0
Aug  3 16:19:17 workstation kernel: fork_trampoline() at  
fork_trampoline+0x8
Aug  3 16:19:17 workstation kernel: --- trap 0x1, eip = 0, esp =  
0xd56ecd6c, ebp = 0 ---


FreeBSD workstation.local 7.0-CURRENT FreeBSD 7.0-CURRENT #0: Sat Jul  
16 15:09:18 CDT 2005     root_at_workstation.local:/usr/obj/usr/src/sys/ 
GENERIC  i386

*****************************

This didn't cause the kernel to panic or anything, I just figured the  
kernel debugger output might be helpful to somebody here...

The same lock order reversal happened the last time I did a clean  
reboot, and this time after a hard restart.

dmesg output is here if needed: http://agentdero.com/~tyler/ 
dmesg.workstation.txt

Is this nothing to worry about? Or is something going slightly wrong?

Cheers,

-R. Tyler Ballance