From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758874AbXI0TBW (ORCPT ); Thu, 27 Sep 2007 15:01:22 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756606AbXI0TBP (ORCPT ); Thu, 27 Sep 2007 15:01:15 -0400 Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:54258 "EHLO sunset.davemloft.net" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1756567AbXI0TBO (ORCPT ); Thu, 27 Sep 2007 15:01:14 -0400 Date: Thu, 27 Sep 2007 12:01:14 -0700 (PDT) Message-Id: <20070927.120114.95884344.davem@davemloft.net> To: helge.hafting@aitel.hist.no Cc: shemminger@linux-foundation.org, jengelh@computergmbh.de, olecom@flower.upol.cz, jbeulich@novell.com, bridge@lists.linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: why network devices don't do reference counting? From: David Miller In-Reply-To: <46FB99EF.4020806@aitel.hist.no> References: <20070926153330.77aade4d@freepuppy.rosehill> <46FB99EF.4020806@aitel.hist.no> X-Mailer: Mew version 5.1.52 on Emacs 21.4 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org From: Helge Hafting Date: Thu, 27 Sep 2007 13:54:23 +0200 > Wouldn't it be enough to down all the interfaces and close all the sockets? > No need to bring down every app. And there are routes, and neighbour cache entries, and all sorts of external references to the stack. For example, if a packet gets stuck in a device because the link just went down, that can hold references to the ipv6 module from several angles. But you have to add code to actually keep track of all of these references and there is no such code in the ipv6 module at all and it's a nontrivial time consuming job to implement it.