[PATCH] Skip down interfaces (v2)

[Brian Haley]

Dan Smith wrote:
> This makes the netns checkpoint code skip interfaces that are not up.
> Later, we want to make it possible to checkpoint down interfaces with
> a flag, but for now this helps prevent people from getting stuck on
> stock kernels with various unsupported and persistent virtual interfaces,
> such as tunnel devices.

But devices that are not IFF_UP can still have addresses associated
with them, wouldn't this cause those addresses to not be
checkpointed?

-Brian