From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pablo Neira Ayuso Subject: Re: [patch 0/6] netfilter: ctnetlink allocation improvement Date: Tue, 17 Mar 2009 11:24:51 +0100 Message-ID: <49BF7A73.3010605@netfilter.org> References: <20090316220659.756862181@jonathan.eitzenberger.org> <49BF28A3.3010606@trash.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Cc: Holger Eitzenberger , David Miller , netfilter-devel@vger.kernel.org, netdev@vger.kernel.org To: Patrick McHardy Return-path: Received: from mail.us.es ([193.147.175.20]:42765 "EHLO us.es" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1757751AbZCQKY7 (ORCPT ); Tue, 17 Mar 2009 06:24:59 -0400 In-Reply-To: <49BF28A3.3010606@trash.net> Sender: netdev-owner@vger.kernel.org List-ID: Hi Patrick, Patrick McHardy wrote: > These patches look almost perfect, there's just one minor thing > that should be fixed from my perspective (from patch 4): > >> + l3proto = nf_ct_l3proto_find_get(tuple->src.l3num); >> + len += l3proto->nla_size; >> + nf_ct_l3proto_put(l3proto); >> + >> + l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, >> tuple->dst.protonum); >> + len += l4proto->nla_size; >> + nf_ct_l4proto_put(l4proto); >> + >> + return alloc_skb(len, gfp); > > Its preferrable not to use module reference counting during packet > processing, the protocols can be accessed safely using RCU. I thought > I had fixed all those areas, but I now notice that ctnetlink is full > of similar spots and takes and drops module references quite > excessively. So just leave it as it is I guess, this should be fully > fixed anyways. Indeed, there are still a couple of module reference spots. We only remove them from the event delivery path. > I'll wait a few hours for others to comment before applying your > patches. Hm, it seems that our patches follows two different principles. AFAICS, Holger calculates an approximate message size to avoid trimming, while I calculate the exact message size. -- "Los honestos son inadaptados sociales" -- Les Luthiers