LOR - pcn vs radix node head (Jan16 -CUR)

This one comes from the same Jan16 -CUR. pcn(4) has the patch I sent 
earlier this week applied. It's non-fatal, and I can't seem to 
reproduce it now. (Multiple attach/detach cycles have not exposed
the ACPI LOR again, hooray!)

ukphy0: detached
miibus0: detached
lock order reversal
1st 0xc214bf90 pcn0 (network driver) _at_ /usr/src/sys/modules/pcn/../../pci/if_pcn.c:1386
2nd 0xc1d0be7c radix node head (radix node head) _at_ net/route.c:1171
KDB: stack backtrace:
witness_checkorder(c1d0be7c,9,c070bfd9,493,9) at witness_checkorder+0x5c6
_mtx_lock_flags(c1d0be7c,0,c070bfd0,493,c1d0be7c) at _mtx_lock_flags+0x54
rtinit(c1f5f900,2,0,c1f5f900,c0745200) at rtinit+0x165
in_ifscrub(c214b800,c1f5f900,c0745200,c07452dc,db26cb38) at in_ifscrub+0x117
rip_ctlinput(0,c1f5f9c4,0,c1f5f900,c214b800) at rip_ctlinput+0x4b
pfctlinput(0,c1f5f9c4,c0767840,0,c214b800) at pfctlinput+0x63
if_down(c214b800,12b,0,c0743440,c0743464) at if_down+0x35
if_detach(c214b800,c214b800,db26cbf8,c2179706,c214b800) at if_detach+0x10e
ether_ifdetach(c214b800,8,c217a7a3,299,c1c59380) at ether_ifdetach+0x23
pcn_detach(c1c59380,c214c850,c073606c,933,c217b990) at pcn_detach+0xd6
device_detach(c1c59380,c217a6f9,c2123740,1,c1c1fa00) at device_detach+0x99
devclass_delete_driver(c1c1fa00,c217b990,1f2,0,c21237c0) at devclass_delete_driver+0xd1
driver_module_handler(c21237c0,1,c217b97c) at driver_module_handler+0xe2
module_unload(c21237c0,0,1f2,c1f5e000,c07001e5) at module_unload+0x68
linker_file_unload(c1f5e000,0,c07001ee,31e,bfbfe8b0) at linker_file_unload+0x29d
kern_kldunload(0,db26cd14,8,3ff,2) at kern_kldunload+0x8c
syscall(2f,2f,2f,3,bfbfee2a) at syscall+0x137
Xint0x80_syscall() at Xint0x80_syscall+0x1f
--- syscall (444, FreeBSD ELF32, kldunloadf), eip = 0x280c459f, esp = 0xbfbfe8ac, ebp = 0xbfbfed24 ---
pcn0: detached

-ksaihr