[PATCH 3/4] Add IPv6 address checkpoint handler

[Serge E. Hallyn]

Quoting Dan Smith (danms at us.ibm.com):
> >> +#ifdef CONFIG_NETNS_CHECKPOING
> 
> SH> How could that be defined?  :)
> 
> Hmm, I must have typo'd that after I did all my config testing because
> otherwise I wouldn't have been able to test checkpointing ipv6 stuff.
> 
> SH> Again, I'd prefer ckpt_err here.
> 
> SH> Note that in my last email that really was a q - if you're under
> SH> spinlock here, then you can't use ckpt_err().
> 
> Right, the point of this loop was to iterate the list quickly while
> holding the device lock, so we could write out the results after we
> release it.
> 
> I think these two cases (and the ipv4 case) are pretty unlikely to be
> a problem as they would only be triggered if you actually have
> active multicast or anycast sessions configured.  This will not
> trigger for the default addresses.
> 
> I don't think that dropping the lock to do ckpt_err() would be very
> pretty, nor would introducing a result string for an error message.

Agreed.

> This is plumbed a couple levels deep.
> 
> Is there some way you see this being handled better?

Not really...  looks like we're doing what we can at the moment
then, good enough :)

thanks,
-serge