From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:48681 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932900AbcGFX4m (ORCPT ); Wed, 6 Jul 2016 19:56:42 -0400 Subject: Patch "net_sched: fix pfifo_head_drop behavior vs backlog" has been added to the 4.6-stable tree To: edumazet@google.com, davem@davemloft.net, gregkh@linuxfoundation.org, jhs@mojatatu.com, xiyou.wangcong@gmail.com Cc: , From: Date: Wed, 06 Jul 2016 16:56:47 -0700 Message-ID: <146784940724075@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled net_sched: fix pfifo_head_drop behavior vs backlog to the 4.6-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: net_sched-fix-pfifo_head_drop-behavior-vs-backlog.patch and it can be found in the queue-4.6 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From foo@baz Wed Jul 6 16:50:56 PDT 2016 From: Eric Dumazet Date: Sun, 12 Jun 2016 20:01:25 -0700 Subject: net_sched: fix pfifo_head_drop behavior vs backlog From: Eric Dumazet [ Upstream commit 6c0d54f1897d229748d4f41ef919078db6db2123 ] When the qdisc is full, we drop a packet at the head of the queue, queue the current skb and return NET_XMIT_CN Now we track backlog on upper qdiscs, we need to call qdisc_tree_reduce_backlog(), even if the qlen did not change. Fixes: 2ccccf5fb43f ("net_sched: update hierarchical backlog too") Signed-off-by: Eric Dumazet Cc: WANG Cong Cc: Jamal Hadi Salim Acked-by: Cong Wang Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/sched/sch_fifo.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/net/sched/sch_fifo.c +++ b/net/sched/sch_fifo.c @@ -37,14 +37,18 @@ static int pfifo_enqueue(struct sk_buff static int pfifo_tail_enqueue(struct sk_buff *skb, struct Qdisc *sch) { + unsigned int prev_backlog; + if (likely(skb_queue_len(&sch->q) < sch->limit)) return qdisc_enqueue_tail(skb, sch); + prev_backlog = sch->qstats.backlog; /* queue full, remove one skb to fulfill the limit */ __qdisc_queue_drop_head(sch, &sch->q); qdisc_qstats_drop(sch); qdisc_enqueue_tail(skb, sch); + qdisc_tree_reduce_backlog(sch, 0, prev_backlog - sch->qstats.backlog); return NET_XMIT_CN; } Patches currently in stable-queue which might be from edumazet@google.com are queue-4.6/netem-fix-a-use-after-free.patch queue-4.6/net_sched-fix-pfifo_head_drop-behavior-vs-backlog.patch