From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756738Ab3LSQL1 (ORCPT ); Thu, 19 Dec 2013 11:11:27 -0500 Received: from mx1.redhat.com ([209.132.183.28]:32145 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754284Ab3LSQLX (ORCPT ); Thu, 19 Dec 2013 11:11:23 -0500 Date: Thu, 19 Dec 2013 11:10:45 -0500 From: Dave Jones To: Peter Zijlstra Cc: Sasha Levin , Ingo Molnar , LKML Subject: Re: lockdep: BUG: MAX_LOCKDEP_ENTRIES too low! Message-ID: <20131219161045.GC25771@redhat.com> Mail-Followup-To: Dave Jones , Peter Zijlstra , Sasha Levin , Ingo Molnar , LKML References: <52B289F4.7060205@oracle.com> <20131219103401.GE30183@twins.programming.kicks-ass.net> <52B2FC66.9010309@oracle.com> <20131219152002.GK16438@laptop.programming.kicks-ass.net> <52B3134D.2010203@oracle.com> <20131219155121.GL16438@laptop.programming.kicks-ass.net> <20131219155917.GB25771@redhat.com> <20131219160116.GC7959@laptop.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20131219160116.GC7959@laptop.programming.kicks-ass.net> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Dec 19, 2013 at 05:01:16PM +0100, Peter Zijlstra wrote: > On Thu, Dec 19, 2013 at 10:59:17AM -0500, Dave Jones wrote: > > On Thu, Dec 19, 2013 at 04:51:21PM +0100, Peter Zijlstra wrote: > > > On Thu, Dec 19, 2013 at 10:39:57AM -0500, Sasha Levin wrote: > > > > That discusses lockdep classes, which is actually fine in my case. I ran out of > > > > MAX_LOCKDEP_ENTRIES, which isn't mentioned anywhere in Documentation/ . > > > > > > Yeah, it suffers from the same problem though. Lockdep has static > > > resource allocation and never frees them. > > > > > > The lock classes are the smallest pool and usually run out first, but > > > the same could happen for the entries, after all, the more classes we > > > have the more class connections can happen. > > > > > > Anyway, barring a leak and silly class mistakes like mentioned in the > > > document there's nothing we can do except raise the number. > > > > I tried this. When you bump it to 32k, it fares better but then you > > start seeing "BUG: MAX_LOCKDEP_CHAINS too low!" instead. > > I've not tried bumping that yet, as I've stopped seeing these lately > > due to hitting more serious bugs first. > > What are you doing to trigger all this? I don't see these. Are you > loading/unloading modules a lot? syscall fuzzing. Dave