From mboxrd@z Thu Jan 1 00:00:00 1970 From: Cong Wang Subject: Re: [PATCH net] net-gro: reset skb->truesize in napi_reuse_skb() Date: Fri, 16 May 2014 14:27:00 -0700 Message-ID: References: <1396542490.12330.17.camel@edumazet-glaptop2.roam.corp.google.com> <20140403.161834.1232262926542795326.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Cc: Eric Dumazet , netdev To: David Miller Return-path: Received: from mail-lb0-f169.google.com ([209.85.217.169]:38979 "EHLO mail-lb0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755468AbaEPV1C (ORCPT ); Fri, 16 May 2014 17:27:02 -0400 Received: by mail-lb0-f169.google.com with SMTP id s7so2390946lbd.28 for ; Fri, 16 May 2014 14:27:00 -0700 (PDT) In-Reply-To: <20140403.161834.1232262926542795326.davem@davemloft.net> Sender: netdev-owner@vger.kernel.org List-ID: On Thu, Apr 3, 2014 at 1:18 PM, David Miller wrote: > From: Eric Dumazet > Date: Thu, 03 Apr 2014 09:28:10 -0700 > >> From: Eric Dumazet >> >> Recycling skb always had been very tough... >> >> This time it appears GRO layer can accumulate skb->truesize >> adjustments made by drivers when they attach a fragment to skb. >> >> skb_gro_receive() can only subtract from skb->truesize the used part >> of a fragment. >> >> I spotted this problem seeing TcpExtPruneCalled and >> TcpExtTCPRcvCollapsed that were unexpected with a recent kernel, where >> TCP receive window should be sized properly to accept traffic coming >> from a driver not overshooting skb->truesize. >> >> Signed-off-by: Eric Dumazet > > Nasty... > > Applied, thanks Eric. I think this patch should be queued for -stable as well? Looking at your stable queue [1], it's not there. :) Thanks! 1. http://patchwork.ozlabs.org/bundle/davem/stable/?state=*