From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH -next] Revert "ipv4: use skb coalescing in defragmentation" Date: Sat, 11 Jul 2015 21:17:14 -0700 (PDT) Message-ID: <20150711.211714.1422141941490741042.davem@davemloft.net> References: <1436571456-27905-1-git-send-email-fw@strlen.de> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, edumazet@google.com To: fw@strlen.de Return-path: Received: from shards.monkeyblade.net ([149.20.54.216]:60392 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750736AbbGLERP (ORCPT ); Sun, 12 Jul 2015 00:17:15 -0400 In-Reply-To: <1436571456-27905-1-git-send-email-fw@strlen.de> Sender: netdev-owner@vger.kernel.org List-ID: From: Florian Westphal Date: Sat, 11 Jul 2015 01:37:36 +0200 > This reverts commit 3cc4949269e01f39443d0fcfffb5bc6b47878d45. > > There is nothing wrong with coalescing during defragmentation, it > reduces truesize overhead and simplifies things for the receiving > socket (no fraglist walk needed). > > However, it also destroys geometry of the original fragments. > While that doesn't cause any breakage (we make sure to not exceed largest > original size) ip_do_fragment contains a 'fastpath' that takes advantage > of a present frag list and results in fragments that (in most cases) > match what was received. > > In case its needed the coalescing could be done later, when we're sure > the skb is not forwarded. But discussion during NFWS resulted in > 'lets just remove this for now'. > > Cc: Eric Dumazet > Signed-off-by: Florian Westphal Applied, thanks for following up on this.