Hi,

I got this crash when I was trying to save a file on union mounted ffs 
filesystems.
The system is NetBSD 4.99.33 updated from CVS around 2007-10-14 with 
applied patches from here:
http://mail-index.netbsd.org/current-users/2007/10/16/0013.html (no idea 
if it is relevant)

panic: lockmgr: release of unlocked lock! (type *0* flags 0, sharecount 
0, exclusivecount 0, recurselevel 0, waitcount 0
fatal breakpoint trap in supervisor mode
trap type 1 code 0 eip c03dd349 cs 9 eflags 246 cr2 0 ilevel 0
Stopped in pid 5832.1 (vim) at  netbsd:breakpoint+0x1:  ret
db> bt         
breakpoint(c048593c,cb2599d6,c0485815,cb259940,0) at netbsd:breakpoint+0x1
lockpanic(cb02fe9c,c0485a94,cb259aac,c032ba88,ca4d7028) at 
netbsd:lockpanic+0xc2

lockmgr(cb02fe9c,6,cb02fe1c,c0950c80,cb02fd60) at netbsd:lockmgr+0x759
ffs_unlock(cb259b00,0,cb259b5c,c044fbe0,cb02fe1c) at netbsd:ffs_unlock+0x3d
VOP_UNLOCK(cb02fe1c,0,cb22e8c0,11,c0a20580) at netbsd:VOP_UNLOCK+0x28      
union_unlock(cb259b40,ca532400,ca532400,c044fbe0,cb02fd60) at 
netbsd:union_unloc
k+0xc8                                                                         
 
VOP_UNLOCK(cb02fd60,0,cb259b8c,c02471dc,cb02fd60) at netbsd:VOP_UNLOCK+0x28
vput(cb02fd60,cb02fe1c,cb259bf0,c09c4960,ca532405) at netbsd:vput+0x31     
union_remove(cb259b9c,c044fda0,c044f8e0,cb02fd60,cb312bc4) at 
netbsd:union_remov
e+0x14c                                                                        
 
VOP_REMOVE(cb02fd60,cb312bc4,cb259bf0,2,0) at netbsd:VOP_REMOVE+0x2b
sys_unlink(cb22e8c0,cb259c48,cb259c68,cb259c50,c03ee705) at 
netbsd:sys_unlink+0x
e5                                                                             
 
syscall_plain() at netbsd:syscall_plain+0x136
--- syscall (number 10) ---                  
0xbbb713c7:                
db>        

Any idea/suggestion/fix is welcome.

Regards,
Juraj