Dependency between interfaces

[Wojciech A. Koszek]

Hello,

Is EVENTHANDLER(9) proper way of notification for standalone driver about
network interface attach/detach operations? I've met simple problem in
ef(4), which causes machine freeze in following situation: load NIC driver
-> load if_ef -> unload NIC driver -> some activity with interface.
Althought driver of network interface no longer exists, if_ef does not know
about it and continues it's operation.

I've seen similar situation for example in ng_fec(4): piece of code needs to
call some cleanup routines in order to keep pointers in valid state. I think
this situation is almost the same like this current in if_bridge(4). Just
repeat situation described above for ef(4), but with if_bridge(4).

Regards,
-- 
* Wojciech A. Koszek && dunstan at FreeBSD.czest.pl