Re: [Patch net-next 2/2] netpoll: use the net namespace of current process instead of init_net

[Cong Wang <amwang@redhat.com>]

On Sat, 2013-01-26 at 21:16 -0800, Eric W. Biederman wrote:
> Cong Wang <amwang@redhat.com> writes:
> 
> > On Wed, 2013-01-23 at 17:02 +0800, Cong Wang wrote:
> >> From: Cong Wang <amwang@redhat.com>
> >> 
> >> This will allow us to setup netconsole in a different namespace
> >> rather than where init_net is.
> >> 
> >
> > Hmm, I missed to put the netns in netpoll_cleanup()...
> >
> > Will send v2.
> 
> Since you are working on it.  I forgot to mention that it doesn't
> look you were working with nsproxy properly.  The code just felt
> very different from every other nsproxy reference I have seen.
> 
> Looking more closely since you are looking at current you don't need
> to test to see if nsproxy is NULL. You can just say.
> 
> -	if (np->dev_name)
> -		ndev = __dev_get_by_name(&init_net, np->dev_name);
> +	if (np->dev_name) {
> +		net = current->nsproxy->net_ns;
> +		ndev = __dev_get_by_name(net, np->dev_name);
> +	}
> 
> task_nsproxy and get_net are needed when you are accessing another
> tasks nsproxy.  Since you are just accessing current the code
> can be much simpler.

Ok.

> 
> Which also means that you shouldn't need to get a reference to
> the network namespace or put the reference to the network namespace.
> Although you do need to handle things like network device hotplug
> in case the network device (or equivalently for most purposes) the
> network namespace goes away.

I believe we already handle NETDEV_UNREGISTER.

Thanks!