From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Denys Fedoryshchenko" Subject: Re: circular locking, mirred, 2.6.24.2 Date: Fri, 7 Mar 2008 01:43:33 +0200 Message-ID: <20080306233151.M43262@visp.net.lb> References: <20080225095646.GA4321@ff.dom.local> <20080225104652.M2446@visp.net.lb> <20080225113930.GA4733@ff.dom.local> <20080305103935.M76165@visp.net.lb> <20080306134015.GA4571@ff.dom.local> <20080306135625.M25627@visp.net.lb> <1204813634.4440.59.camel@localhost> <20080306143910.M91001@visp.net.lb> <20080306202551.GB2876@ami.dom.local> <1204837000.4457.108.camel@localhost> <20080306221253.GD2876@ami.dom.local> Mime-Version: 1.0 Content-Type: text/plain; charset=koi8-r Cc: netdev@vger.kernel.org To: jamal , Jarek Poplawski Return-path: Received: from usermail.globalproof.net ([194.146.153.18]:58978 "EHLO usermail.globalproof.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756229AbYCFXny (ORCPT ); Thu, 6 Mar 2008 18:43:54 -0500 In-Reply-To: <20080306221253.GD2876@ami.dom.local> Sender: netdev-owner@vger.kernel.org List-ID: About reproducing, I think .config matter Mine is at http://www.nuclearcat.com/files/config.txt About hardware, maybe it is important - it is Intel dual core machine (32- bit). I test few more times, i can reproduce it for sure. It gives lockdep on first incoming packet. More info about hardware: CPU model name : Intel(R) Core(TM)2 CPU 6600 @ 2.40GHz Other machines where i get this lockdep also Core Duo CPU's. I test now on old 2xXeon,P4 with hyperthreading - also triggered. Shortest script i use: modprobe ifb ifconfig ifb0 up /sbin/tc qdisc del dev eth0 ingress 1>/dev/null 2>/dev/null /sbin/tc qdisc add dev eth0 ingress /sbin/tc filter add dev eth0 parent ffff: protocol ip prio 10 u32 \ match u32 0 0 flowid 1:1 \ action mirred egress redirect dev ifb0 On Thu, 6 Mar 2008 23:12:53 +0100, Jarek Poplawski wrote > On Thu, Mar 06, 2008 at 03:56:40PM -0500, jamal wrote: > > On Thu, 2008-06-03 at 21:25 +0100, Jarek Poplawski wrote: > > > > > It's really strange: I can't reproduce this, > > > > I couldnt either - are you using 2.6.25-rc4? > > No, David's net-2.6 tree so 2.6.25-rc3 plus something... > > > > > > and if it were so easy we > > > would get really a lot of similar reports. It looks like you have > > > something special. This lockdep report with this kind of problem > > > usually looks different too. The good side is it's easy to reproduce. > > > So, could you try the patch below? (It's only supposed to fix the lockdep > > > warning, not lockups). > > > > This is more out of ignorance: Why is ifb needing the extra teaching for > > lockdep? It is a netdevice - shouldnt the two global lockdeps you > > described earlier not be sufficient? > > As I've written in the previous message, currently lockdep tracks > dev->queue_lock and dev->ingress_lock as only two locks used by all > net devices (unless they were annotated individually). So, it's like > A and B lock, and it's really not right to them AB in one place, and > BA in another. In reality each net_device's locks are independent, > so ifb has C and D. And it's not AB vs. BA, but: AB (eth/lo- > >queue_lock, eth/lo->ingress_lock), CD (the same for ifb) and BC > (eth/lo->ingress_lock, ifb->queue_lock) - all legal combinations, > and no inversion. > > Cheers, > Jarek P. > -- > To unsubscribe from this list: send the line "unsubscribe netdev" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Denys Fedoryshchenko Technical Manager Virtual ISP S.A.L.