From mboxrd@z Thu Jan 1 00:00:00 1970 From: KOVACS Krisztian Subject: Re: [PATCH net-next-2.6] netfilter: allow nf_tproxy_core module to be removed Date: Fri, 25 Jun 2010 09:56:57 +0200 Message-ID: <4C246149.3090603@sch.bme.hu> References: <20100623183503.GE2687@psychotron.bos.redhat.com> <20100623184611.GG27132@Chamillionaire.breakpoint.cc> <20100623.115558.189705237.davem@davemloft.net> <4C2379D9.2080608@trash.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7BIT Cc: David Miller , fw@strlen.de, jpirko@redhat.com, netdev@vger.kernel.org, Balazs Scheidler To: Patrick McHardy Return-path: Received: from balu.sch.bme.hu ([152.66.208.40]:47576 "EHLO balu.sch.bme.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751558Ab0FYI5G (ORCPT ); Fri, 25 Jun 2010 04:57:06 -0400 Received: from [IPv6:::1] ([152.66.208.86]) by balu.sch.bme.hu (Sun Java System Messaging Server 6.2-7.05 (built Sep 5 2006)) with ESMTPSA id <0L4K00EKF8QXQDC0@balu.sch.bme.hu> for netdev@vger.kernel.org; Fri, 25 Jun 2010 09:57:01 +0200 (CEST) In-reply-to: <4C2379D9.2080608@trash.net> Sender: netdev-owner@vger.kernel.org List-ID: Hi, On 06/24/2010 05:29 PM, Patrick McHardy wrote: > David Miller wrote: >> From: Florian Westphal >> Date: Wed, 23 Jun 2010 20:46:11 +0200 >> >>> tproxy assigns skb->destructor, what prevents module unload while >>> such skbs may >>> still be around? >> >> The only reference to nf_tproxy_core.ko is for the symbol, >> "nf_tproxy_assign_sock". >> xt_TPROXY.c, which references this symbol, thus creates a symbol >> dependency on this >> module, so xt_TPROXY.o needs to unload before nf_tproxy_core.ko can >> unload, and >> xt_TPROXY.o has it's own manner for handling module references properly. > > I don't see anything waiting for skbs in flight using the tproxy > destructor in either xt_TPROXY or nf_tproxy_core though, so I think > Florian is correct. Yes, I think Florian and Patrick's right. Right now there's nothing preventing xt_TPROXY and nf_tproxy_core from being removed while there are skbs in flight with the tproxy destructor set. -- KOVACS Krisztian