panic with RAIDFRAME_CONFIGURE ioctl (lockmgr: thread 0xc7a8c3c0, not exclusive lock holder 0xc3b1b4c0 unlocking)

I'm having a panic when attempting to configure a RAID 1 volume
under -current. The panic occurs when I run "raidctl -C /etc/raid0.conf"
with the following config:

--->8--->8--->8--->8--->8--->8--->8--->8--->8
START array
# numRow numCol numSpare
1 2 0

START disks
/dev/da1s1a
/dev/da2s1a

START layout
128 1 1 1

START queue
fifo 100
--->8--->8--->8--->8--->8--->8--->8--->8--->8

I have no idea where this comes from, I am still looking at it. The
crash dump is available in case anyone wants more information.

panic: lockmgr: thread 0xc7a8c3c0, not exclusive lock holder 0xc3b1b4c0 unlockin
g
panic messages:
---
panic: lockmgr: thread 0xc7a8c3c0, not exclusive lock holder 0xc3b1b4c0 unlockin
g
cpuid = 0; lapic.id = 00000000
boot() called on cpu#0

[...]

#0  doadump () at ../../../kern/kern_shutdown.c:238
#1  0xc01d2f43 in boot (howto=256) at ../../../kern/kern_shutdown.c:370
#2  0xc01d32ff in panic () at ../../../kern/kern_shutdown.c:543
#3  0xc01c66de in lockmgr (lkp=0xc7d279dc, flags=6, interlkp=0x1000000, 
    td=0xc7a8c3c0) at ../../../kern/kern_lock.c:422
#4  0xc022063f in vop_stdunlock (ap=0x0) at ../../../kern/vfs_default.c:322
#5  0xc0220458 in vop_defaultop (ap=0x0) at ../../../kern/vfs_default.c:163
#6  0xc019ddf8 in spec_vnoperate (ap=0x0)
    at ../../../fs/specfs/spec_vnops.c:123
#7  0xc7da5b4c in raidlookup (path=0x0, td=0xc7a8c3c0, vpp=0x0)
    at vnode_if.h:1021
#8  0xc7da7457 in raid_getcomponentsize (raidPtr=0xc7dc6000, row=0, col=0)
    at /usr/src/sys/dev/raidframe/rf_freebsdkintf.c:3106
#9  0xc7d77546 in rf_ConfigureDisk (raidPtr=0xc7dc6000, buf=0x0, 
    diskPtr=0xc7cec800, row=0, col=0)
    at /usr/src/sys/dev/raidframe/rf_disks.c:631
#10 0xc7d76781 in rf_ConfigureDisks (listp=0xc7dc610c, raidPtr=0xc7dc6000, 
    cfgPtr=0xc7d2a000) at /usr/src/sys/dev/raidframe/rf_disks.c:140
#11 0xc7d792a0 in rf_Configure (raidPtr=0xc7dc6000, cfgPtr=0xc7d2a000, ac=0x0)
    at /usr/src/sys/dev/raidframe/rf_driver.c:495
#12 0xc7da3c40 in raidctlioctl (dev=0xc7d0b000, cmd=0, data=0x0, flags=3, 
    td=0xc3b1b4c0) at /usr/src/sys/dev/raidframe/rf_freebsdkintf.c:550
#13 0xc019e6be in spec_ioctl (ap=0x0) at ../../../fs/specfs/spec_vnops.c:347
#14 0xc019ddf8 in spec_vnoperate (ap=0x0)
    at ../../../fs/specfs/spec_vnops.c:123
#15 0xc0235231 in vn_ioctl (fp=0xc7d1cb40, com=2147774977, data=0xe1236c54, 
    active_cred=0xc3b12280, td=0xc3b1b4c0) at vnode_if.h:488
#16 0xc01f9498 in ioctl (td=0xc3b1b4c0, uap=0xe1236d10) at file.h:251
#17 0xc02fe14e in syscall (frame=
      {tf_fs = 47, tf_es = 47, tf_ds = 47, tf_edi = 3, tf_esi = 3, tf_ebp = -1077969192, tf_isp = -517771916, tf_ebx = 1, tf_edx = 134635520, tf_ecx = 0, tf_eax = 54, tf_trapno = 12, tf_err = 2, tf_eip = 134526559, tf_cs = 31, tf_eflags = 646, tf_esp = -1077969220, tf_ss = 47}) at ../../../i386/i386/trap.c:1021
#18 0xc02e620d in Xint0x80_syscall () at {standard input}:139

-- 
Pierre Beyssac						pb_at_enst.fr