Hi,
I just got this on a 2.0/alpha system doing a bulk build:
panic: lockmgr: release of unlocked lock!
db> tr
cpu_Debugger() at netbsd:cpu_Debugger+0x4
panic() at netbsd:panic+0x1f8
lockmgr() at netbsd:lockmgr+0x308
layer_unlock() at netbsd:layer_unlock+0x98
VOP_UNLOCK() at netbsd:VOP_UNLOCK+0x3c
vput() at netbsd:vput+0x5c
lookup() at netbsd:lookup+0x44c
namei() at netbsd:namei+0x1bc
elf64_load_file() at netbsd:elf64_load_file+0x84
exec_elf64_makecmds() at netbsd:exec_elf64_makecmds+0x260
check_exec() at netbsd:check_exec+0x294
sys_execve() at netbsd:sys_execve+0x138
syscall_plain() at netbsd:syscall_plain+0xc4
XentSys() at netbsd:XentSys+0x5c
--- syscall (59) ---
--- user mode ---
db> 

Just before the panic there is:
vnode: table is full - increase kern.maxvnodes or NVNODE

I don't know if it's related or not.

-- 
Manuel Bouyer <bouyer@antioche.eu.org>
     NetBSD: 26 ans d'experience feront toujours la difference
--