> Routers have a tendency not to announce routes for networks
> that are physically down, i miss that in linux. Mr. Becker
> suggested using libmii was a no-no-never solution (up to a few
> ms lockup of the machine per poll) for this issue. Select as
> you suggest seems ideal.
mm.. I've clocked an mdio_read() at 300 usecs. Not a thing you'd want
to poll very frequently, particularly as some drivers are racy in this
area, and the consequences of hitting the race could be quite bad.
spin_lock_bh() is the correct solution for mdio protection, BTW.
Of course, with many devices you simply _have_ to poll.
But if someone is setting up a multi-node HA system or a router, it's
not unreasonable to expect them to fork out the $$$ for a NIC which
generates link status change interrupts, and to be prepared to use