Re: [PATCH net-next] pkt_sched: namespace aware ifb

[Eric Dumazet <eric.dumazet@gmail.com>]

On Sun, 2013-01-13 at 11:41 -0500, Benjamin LaHaise wrote:
> Hi folks,
> 
> On Sun, Jan 13, 2013 at 09:44:48AM -0500, Jamal Hadi Salim wrote:
> > Eric, the point probably Ben was trying to make is not about 
> > synchronizing rather about which namespace has the right to that action 
> > config. Your change is correct for the common use of actions
> > but does not fix the larger picture.
> ...
> > In such a case, the "tc actions" netlink path may be
> > entered from a different namespace than the one that is
> > using it. Then current->nsproxy->net_ns is no longer correct.
> > 
> > To correct this, i think what Ben points out in passing the
> > init() the correct namespace seem like the way to go. Feel free
> > to make that change - otherwise i will get to it and fix it.
> 
> Yep, Jamal's right on the point I'm trying to make.  To deal with this, I 
> think we need a patch along the lines of the following to pass the 'struct 
> net *' down to where it's needed...  Please note that I've only compile 
> tested this with all the net/sched modules enabled and a allmodconfig 
> build.  It's a bit bigger, but passing the argument down through the call 
> chain looks simpler than trying to stuff a struct net pointer into the 
> various structures and keep that in sync with the network device's network 
> namespace.
> 
> 		-ben
> -- 
> "Thought is the essence of where you are now."
> 
> -- 
> pkt_sched: namespace aware ifb v2
> 
> Eric Dumazet pointed out that act_mirred needs to find the current net_ns,
> and struct net pointer is not provided in the call chain.  His original
> patch made use of current->nsproxy->net_ns to find the network namespace,
> but this fails to work correctly for userspace code that makes use of
> netlink sockets in different network namespaces.  Instead, pass the
> "struct net *" down along the call chain to where it is needed.
> 
> Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
> ---

OK I'll test it at the end of the (sunny) day.

Thanks