From: Chrissie Caulfield Subject: Re: [PATCH 07/10] decnet: Use rcu_barrier() on module unload. Date: Wed, 24 Jun 2009 14:50:42 +0100 Message-ID: <5A680E0A-EFEB-44EA-9F06-F338E6CBD6D1@googlemail.com> References: <20090623150330.22490.87327.stgit@localhost> <20090623150429.22490.15113.stgit@localhost> <4A41C67E.8070301@googlemail.com> <1245843884.6695.54.camel@localhost.localdomain> <1245845367.24921.3.camel@localhost.localdomain> Mime-Version: 1.0 (Apple Message framework v935.3) Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes Cc: "David S. Miller" , "Paul E. McKenney" , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, dougthompson@xmission.com, axboe@kernel.dk, Patrick McHardy , Trond.Myklebust@netapp.com, johannes@sipsolutions.net, yoshfuji@linux-ipv6.org, shemminger@linux-foundation.org, linux-nfs@vger.kernel.org, bfields@fieldses.org, neilb@suse.de, linux-ext4@vger.kernel.org, tytso@mit.edu, adilger-xsfywfwIY+M@public.gmane.org, netfilter-devel@vger.kernel.org To: jdb-4UpuNZONu4c@public.gmane.org Return-path: Received: from mtaout01-winn.ispmail.ntl.com ([81.103.221.47]:54002 "EHLO mtaout01-winn.ispmail.ntl.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752735AbZFXNuw (ORCPT ); Wed, 24 Jun 2009 09:50:52 -0400 In-Reply-To: <1245845367.24921.3.camel-bi+AKbBUZKY6gyzm1THtWbp2dZbC/Bob@public.gmane.org> Sender: linux-nfs-owner@vger.kernel.org List-ID: On 24 Jun 2009, at 13:09, Jesper Dangaard Brouer wrote: > On Wed, 2009-06-24 at 13:44 +0200, Jesper Dangaard Brouer wrote: >> On Wed, 2009-06-24 at 07:23 +0100, Chrissie Caulfield wrote: >>> The issues with DECnet module unloading are a little more than >>> just an >>> RCU leak I think! >>> >>> Though that area does need reviewing ... when I get some time. >> >> Fine. Now you have read my comment in the code, then there is a >> updated >> patch below. Will you ack-that? > I don't have any objection to the patch at all, it just seemed a little odd to deliberately add code inside #if 0 ;-) Chrissie > Sorry wrong patch... forgot save the code and 'stg refresh'... > > [PATCH 07/10] decnet: Use rcu_barrier() on module unload. > > From: Jesper Dangaard Brouer > > The decnet module unloading as been disabled with a '#if 0' statement, > because it have had issues. > > We add a rcu_barrier() anyhow for correctness. > > The maintainer (Chrissie Caulfield) will look into the unload issue > when time permits. > > Signed-off-by: Jesper Dangaard Brouer > --- > > net/decnet/af_decnet.c | 2 ++ > 1 files changed, 2 insertions(+), 0 deletions(-) > > > diff --git a/net/decnet/af_decnet.c b/net/decnet/af_decnet.c > index d351b8d..77d4028 100644 > --- a/net/decnet/af_decnet.c > +++ b/net/decnet/af_decnet.c > @@ -2413,6 +2413,8 @@ static void __exit decnet_exit(void) > proc_net_remove(&init_net, "decnet"); > > proto_unregister(&dn_proto); > + > + rcu_barrier_bh(); /* Wait for completion of call_rcu_bh()'s */ > } > module_exit(decnet_exit); > #endif > >