Code review comment for lp:~allenap/maas/tftp-rebind-on-netif-change

> Are we using threads anywhere in pserv (other than spawning one after the
> HUP)? Signals don't play nice with threads but it may be moot if Twisted is
> DTRT.

Nope, don't think we're using threads. However, I've been cautious;
reactor.callFromThread will DTRT whether the handler runs in the reactor
thread or outside.

>
> Anyway, lovely change.

Thanks for the review!