Multiple instances of tap0 and panic when destroying

[Rumko]

Had a tap0 configured through rc.conf at boot-time, and started a vkernel
with -I tap0:bridge0.
When I did this, I noticed that another tap0 was created (doing "ifconfig"
showed 2 tap0 devices with different MAC addresses), so I did a "ifconfig tap0
destroy" and got a panic.

The kernel.X and vmcore.X are at leaf:~rumko/crash/tap/, sources used from
approximately 13:00 CEST today.

Backtrace:
Unread portion of the kernel message buffer:
panic: Bad link elm 0xd2721368 next->prev != elm
mp_lock = 00000001; cpuid = 1
Trace beginning at frame 0xdde4a960
panic(dde4a984,dd4d8300,c39093a0,dd490398,dde4a990) at panic+0x14d
panic(c04088a4,d2721368,dd4d8300,dd4903a4,dde4aaac) at panic+0x14d
eventhandler_deregister(c39093a0,d2721368) at eventhandler_deregister+0x31
pfi_detach_ifnet(dd490398) at pfi_detach_ifnet+0xc0
pfi_detach_ifnet_event(0,dd490398,d2720f30,c0451e20,dd490398) at
pfi_detach_ifnet_event+0xb
if_detach(dd490398,dd490398) at if_detach+0x2b
ether_ifdetach(dd490398,dd490398,0,dd490398,0) at ether_ifdetach+0x2b
tapdestroy(c0453240,dde4ac1c,dde4ab44,c026a88e,dd490398) at tapdestroy+0x66
tap_clone_destroy(dd490398,0,dde4ac1c,dde4ac1c,dde4abc4) at
tap_clone_destroy+0x45
if_clone_destroy(dde4ac1c,dd4dd000,0,0,dde4aba8) at if_clone_destroy+0x45
ifioctl(dd412e00,80206979,dde4ac1c,dd870288,0) at ifioctl+0x26f
soo_ioctl(dd384ea8,80206979,dde4ac1c,dd870288,dd384ea8) at soo_ioctl+0x13b
mapped_ioctl(3,80206979,80d9900,0,dde4ad34) at mapped_ioctl+0x3e1
sys_ioctl(dde4acf0,6,0,0,d8f84698) at sys_ioctl+0x16
syscall2(dde4ad40) at syscall2+0x265
Xint0x80_syscall() at Xint0x80_syscall+0x36
boot() called on cpu#1
Uptime: 3h38m6s
-- 
Regards,
Rumko