From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [net-next PATCH 3/3] net: frag queue per hash bucket locking Date: Fri, 29 Mar 2013 15:22:59 -0400 (EDT) Message-ID: <20130329.152259.696287122868561280.davem@davemloft.net> References: <1364513982.15753.57.camel@edumazet-glaptop> <20130329003308.GD20223@order.stressinduktion.org> <1364583693.3232.257.camel@localhost> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: hannes@stressinduktion.org, eric.dumazet@gmail.com, netdev@vger.kernel.org, fw@strlen.de, dborkman@redhat.com To: brouer@redhat.com Return-path: Received: from shards.monkeyblade.net ([149.20.54.216]:56267 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756255Ab3C2TXA (ORCPT ); Fri, 29 Mar 2013 15:23:00 -0400 In-Reply-To: <1364583693.3232.257.camel@localhost> Sender: netdev-owner@vger.kernel.org List-ID: From: Jesper Dangaard Brouer Date: Fri, 29 Mar 2013 20:01:33 +0100 > On Fri, 2013-03-29 at 01:33 +0100, Hannes Frederic Sowa wrote: >> On Thu, Mar 28, 2013 at 04:39:42PM -0700, Eric Dumazet wrote: >> > On Fri, 2013-03-29 at 00:30 +0100, Hannes Frederic Sowa wrote: >> > > On Thu, Mar 28, 2013 at 01:22:44PM -0700, Eric Dumazet wrote: >> > > > On Thu, 2013-03-28 at 19:57 +0100, Hannes Frederic Sowa wrote: >> > > > >> > > > > I assume that it has to do with the usage of this code in >> > > > > ipv6/netfilter/nf_conntrack_reasm.c, which could be invoked from process >> > > > > context, if I read it correctly. >> > > > >> > > > Then there would be a possible deadlock in current code. >> > > >> > > Netfilter currently does a local_bh_disable() before entering inet_fragment >> > > (and later enables it, again). >> > > >> > >> > Good, so no need for the _bh() as I suspected. >> >> Ack. >> >> I replaced the _bh spin_locks with plain spinlocks and tested the code >> with sending fragments and receiving fragments (netfilter and reassmbly >> logic) with lockdep and didn't get any splats. Looks good so far. > > Well, it's great to see, that you are working on solving my patch > proposal. While I'm on Easter vacation ;-) Much appreciated. > I'm officially back from vacation Tuesday, and I'll repost then (after > testing it on my 10G testlab). Jesper, when you do this, please just put the whole of the excellent description text you had in the "0/3" posting from this series into the commit message for the respun patch #3. Thanks.