From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757537Ab3BFQHY (ORCPT ); Wed, 6 Feb 2013 11:07:24 -0500 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.122]:27268 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755083Ab3BFQHW (ORCPT ); Wed, 6 Feb 2013 11:07:22 -0500 X-Authority-Analysis: v=2.0 cv=bJmU0YCZ c=1 sm=0 a=rXTBtCOcEpjy1lPqhTCpEQ==:17 a=mNMOxpOpBa8A:10 a=_Bp3_fu7e2UA:10 a=5SG0PmZfjMsA:10 a=Q9fys5e9bTEA:10 a=meVymXHHAAAA:8 a=wIfm1DkAj9kA:10 a=uYVGJH5IAAAA:8 a=dprfMjs3EWEHZhD5L78A:9 a=PUjeQqilurYA:10 a=rXTBtCOcEpjy1lPqhTCpEQ==:117 X-Cloudmark-Score: 0 X-Authenticated-User: X-Originating-IP: 74.67.115.198 Message-ID: <1360166840.2621.45.camel@gandalf.local.home> Subject: Re: Question on lockdep and MAX_LOCK_DEPTH From: Steven Rostedt To: Ben Greear Cc: Linux Kernel Mailing List , Peter Zijlstra , Ingo Molnar Date: Wed, 06 Feb 2013 11:07:20 -0500 In-Reply-To: <51127D15.7080503@candelatech.com> References: <5111AD8D.1080005@candelatech.com> <20130206015430.GA9161@home.goodmis.org> <5111BF51.5010607@candelatech.com> <1360119124.2621.37.camel@gandalf.local.home> <5111CE60.4080403@candelatech.com> <1360125419.2621.39.camel@gandalf.local.home> <5111F6F6.7010402@candelatech.com> <1360156888.2621.42.camel@gandalf.local.home> <51127D15.7080503@candelatech.com> Content-Type: text/plain; charset="ISO-8859-15" X-Mailer: Evolution 3.4.4-1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2013-02-06 at 07:56 -0800, Ben Greear wrote: > > I'm 99% sure that the bug is in your modifications. > > I'm sorry, I tried to make that clear. You said it was an out of tree module, I didn't realize it had changes to the core Linux as well. > My tree is here, minus a few debugging patches related to this bug: > > http://dmz2.candelatech.com/git/gitweb.cgi?p=linux-3.7.dev.y/.git;a=summary Here's your bug: 3319 list_for_each_entry_rcu(ptype, &ptype_all, list) { 3320 if (!ptype->dev || ptype->dev == skb->dev) { 3321 if (pt_prev) { 3322 ret = deliver_skb(skb, pt_prev, orig_dev); 3323 if (ret == NET_RX_CONSUMED) { 3324 kfree_skb(skb); /* we made a copy in deliver_skb */ 3325 goto out; 3326 } 3327 } One of many. All those "goto out;"s skip the rcu_read_unlock(). -- Steve