[PATCH 16/33] netns ct: per-netns event cache

[Patrick McHardy]

Alexey Dobriyan wrote:
> Heh, last minute proof-reading of this patch made me think,
> that this is actually unneeded, simply because "ct" pointers will be
> different for different conntracks in different netns, just like they
> are different in one netns.
> 
> Not so sure anymore.

Its necessary because the cache needs to be flushed on netns exit
and this is only allowed while its not in use anymore.

I don't see anything in this series actually making sure nothing
hits the cache on exit though. Am I missing something?

Additionally (I might have missed a following patch moving it
out though) this doesn't belong in the netns exit path:

void nf_conntrack_cleanup(struct net *net)
{
	rcu_assign_pointer(ip_ct_attach, NULL);
...
	rcu_assign_pointer(nf_ct_destroy, NULL);