VFS lockdebug panic

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

Hi
I just got this panic on a -current system:
savecore: /dev/wd0a: Device not configured
Mar  7 00:43:39 comore savecore: /dev/wd0a: Device not configured
Mounting all filesystems...
Reader / writer lock error: rw_vector_exit: assertion failed: RW_COUNT(rw) != 0

lock address : 0xffffa000045a4610
current cpu  :                  0
current lwp  : 0xffffa000044ca7e0
owner/count  : 000000000000000000 flags    : 000000000000000000

panic: lock error
fatal breakpoint trap in supervisor mode
trap type 1 code 0 rip ffffffff8012ee5d cs e030 rflags 246 cr2  7f7ffd96a190 
cpl 0 rsp ffffa000045ff690
Stopped in pid 164.1 (mount_ffs) at     netbsd:breakpoint+0x5:  leave
breakpoint() at netbsd:breakpoint+0x5
panic() at netbsd:panic+0x242
lockdebug_abort() at netbsd:lockdebug_abort+0x42
rw_vector_exit() at netbsd:rw_vector_exit+0xa6
vlockmgr() at netbsd:vlockmgr+0xd8
VOP_UNLOCK() at netbsd:VOP_UNLOCK+0x28
spec_open() at netbsd:spec_open+0x33e
VOP_OPEN() at netbsd:VOP_OPEN+0x29
ffs_mount() at netbsd:ffs_mount+0x33b
do_sys_mount() at netbsd:do_sys_mount+0x62d
sys___mount50() at netbsd:sys___mount50+0x33
syscall() at netbsd:syscall+0xb4

any idea ?

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