Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755241AbbKDEZn (ORCPT ); Tue, 3 Nov 2015 23:25:43 -0500 Received: from hosting.visp.net.lb ([194.146.153.11]:42590 "EHLO hosting.visp.net.lb" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754990AbbKDEZg (ORCPT ); Tue, 3 Nov 2015 23:25:36 -0500 MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Wed, 04 Nov 2015 06:25:29 +0200 From: Denys Fedoryshchenko To: Cong Wang Cc: Jamal Hadi Salim , "David S. Miller" , netdev , linux-kernel@vger.kernel.org Subject: Re: kernel panic in 4.2.3, rb_erase in sch_fq In-Reply-To: References: Message-ID: <0705e2b76150c28341d7e1915433450d@visp.net.lb> User-Agent: VISP Webmail/0.8.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2787 Lines: 67 On 2015-11-04 00:06, Cong Wang wrote: > On Mon, Nov 2, 2015 at 6:11 AM, Denys Fedoryshchenko > wrote: >> Hi! >> >> Actually seems i was getting this panic for a while (once per week) on >> loaded pppoe server, but just now was able to get full panic message. >> After checking commit logs on sch_fq.c i didnt seen any fixes, so >> probably >> upgrading to newer kernel wont help? > > > Can you share your `tc qdisc show dev xxxx` with us? And how to > reproduce > it? I tried to setup htb+fq and then flip the interface back and forth > but I don't > see any crash. My guess it wont be easy to reproduce, it is happening on box with 4.5k interfaces, that constantly create/delete interfaces, and even with that this problem may happen once per day, or may not happen for 1 week. Here is script that is being fired after new ppp interface detected. But pppoe process are independent from process that are "establishing" shapers. /sbin/tc qdisc del root /sbin/tc qdisc add handle 1: root htb default 3 /sbin/tc filter add parent 1:0 protocol ip prio 4 handle 1 fw flowid 1:3 /sbin/tc filter add parent 1:0 protocol ip prio 3 u32 match ip protocol 6 0xff match ip src 10.0.252.8/32 flowid 1:3/sbin/tc filter add parent 1:0 protocol ip prio 5 u32 match ip protocol 1 0xff flowid 1:0 /sbin/tc filter add parent 1:0 protocol ip prio 5 u32 match ip protocol 6 0xff match ip sport 80 0xffff flowid 1:4 /sbin/tc filter add parent 1:0 protocol ip prio 5 u32 match ip protocol 6 0xff match ip sport 443 0xffff flowid 1:5 /sbin/tc filter add parent 1:0 protocol ip prio 100 u32 match u32 0 0 flowid 1:2 /sbin/tc class add classid 1:1 parent 1:0 htb rate 512Kbit ceil 512Kbit. /sbin/tc class add classid 1:2 parent 1:1 htb rate 32Kbit ceil 512Kbit /sbin/tc class add classid 1:3 parent 1:0 htb rate 10Mbit ceil 10Mbit /sbin/tc class add classid 1:4 parent 1:1 htb rate 32Kbit ceil 512Kbit /sbin/tc class add classid 1:5 parent 1:1 htb rate 32Kbit ceil 512Kbit /sbin/tc qdisc add parent 1:2 fq limit 300 /sbin/tc qdisc add parent 1:3 pfifo limit 300 /sbin/tc qdisc add parent 1:4 fq limit 300 /sbin/tc qdisc add parent 1:5 fq limit 300 Possible cases come to my mind (but maybe i missed others): Script and tc working and interface are deleted in a process (e.g. interface disappears) Script deleting root while there is heavy traffic on interface and a lot of packets queued ppp interface destroyed, while there is a lot of traffic queued on it (this one a bit rare situation) > > Thanks. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/