Re: [PATCH 2/2] IPVS: Add genetlink interface implementation

[Thomas Graf <tgraf@suug.ch>]

* Julius Volz <juliusv@google.com> 2008-07-10 15:58
> On Thu, Jul 10, 2008 at 2:15 PM, Patrick McHardy <kaber@trash.net> wrote:
> > There probably should be a struct module *owner in the
> > ops registered with genetlink. This is necessary at
> > least to make sure that modules don't disappear during
> > dumps.
> 
> There seems to be no such thing in genetlink. af_netlink.c tracks the
> owner of a netlink socket, but that would increase the use count of
> the genetlink module.
> 
> First I would have suspected the genl_mutex to be held while dumping,
> so that at least unregistering the family at module unload would
> block. But the mutex is explicitly unlocked for the duration of the
> netlink dump:

It used to be like before the locking during dumps was revised. I
promised to redo the locking and module owner tracking but haven't
gotten around. Patrick's suggestion certainly makes sense.

> net/netlink/genetlink.c:
> 
>                 genl_unlock();
>                 err = netlink_dump_start(genl_sock, skb, nlh,
>                                          ops->dumpit, ops->done);
>                 genl_lock();
> 
> Julius