From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH 0/3] ipv4: pmtu fixes Date: Mon, 08 Oct 2012 14:47:13 -0400 (EDT) Message-ID: <20121008.144713.729746528422701623.davem@davemloft.net> References: <20121008084642.GB15622@secunet.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org To: steffen.klassert@secunet.com Return-path: Received: from shards.monkeyblade.net ([149.20.54.216]:56889 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753480Ab2JHSrP (ORCPT ); Mon, 8 Oct 2012 14:47:15 -0400 In-Reply-To: <20121008084642.GB15622@secunet.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Steffen Klassert Date: Mon, 8 Oct 2012 10:46:42 +0200 > This patchset fixes some issues that came with the routing cache removal. > > 1) IPsec and others (udp, ipvs) may cache output routes, these routes > need to be invalidated on pmtu events in the same way e.g. tcp socket > cached routes are invalidated. With this we always invalidate or update > (if we already use a nh exeption route) the old route on pmtu events. > > This has the drawback that we may needlessly invalidate an uncached route, > but this fixes all the users that cache routes and pmtu events are rare, so > this should not be a real issue. > > 2) We create nh exeptions if a user (e.g. tracepath) tries to do pmtu > dicsovery with packets bigger than the output device mtu. The device mtu > is not learned and does not expire, so don't create an exeption route. > > 3) We report cached pmtu values to userspace even if they are expired. > Fix this by checking for expiration before we report. All applied and queued up for -stable, thanks!