From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754474Ab1HNQXT (ORCPT ); Sun, 14 Aug 2011 12:23:19 -0400 Received: from cantor2.suse.de ([195.135.220.15]:36648 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754333Ab1HNQIY (ORCPT ); Sun, 14 Aug 2011 12:08:24 -0400 X-Mailbox-Line: From gregkh@clark.kroah.org Fri Aug 12 14:05:56 2011 Message-Id: <20110812210556.405297273@clark.kroah.org> User-Agent: quilt/0.48-16.4 Date: Fri, 12 Aug 2011 14:04:34 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Eric Dumazet , Michal Soltys , Patrick McHardy , "David S. Miller" Subject: [49/90] sch_sfq: fix sfq_enqueue() In-Reply-To: <20110812210626.GA4725@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.0-stable review patch. If anyone has any objections, please let us know. ------------------ From: Eric Dumazet [ Upstream commit e1738bd9cecc5c867b0e2996470c1ff20f66ba79 ] commit 8efa88540635 (sch_sfq: avoid giving spurious NET_XMIT_CN signals) forgot to call qdisc_tree_decrease_qlen() to signal upper levels that a packet (from another flow) was dropped, leading to various problems. With help from Michal Soltys and Michal Pokrywka, who did a bisection. Bugzilla ref: https://bugzilla.kernel.org/show_bug.cgi?id=39372 Debian ref: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=631945 Reported-by: Lucas Bocchi Reported-and-bisected-by: Michal Pokrywka Signed-off-by: Eric Dumazet CC: Michal Soltys Acked-by: Patrick McHardy Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/sched/sch_sfq.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) --- a/net/sched/sch_sfq.c +++ b/net/sched/sch_sfq.c @@ -410,7 +410,12 @@ sfq_enqueue(struct sk_buff *skb, struct /* Return Congestion Notification only if we dropped a packet * from this flow. */ - return (qlen != slot->qlen) ? NET_XMIT_CN : NET_XMIT_SUCCESS; + if (qlen != slot->qlen) + return NET_XMIT_CN; + + /* As we dropped a packet, better let upper stack know this */ + qdisc_tree_decrease_qlen(sch, 1); + return NET_XMIT_SUCCESS; } static struct sk_buff *