Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758019AbZGGPzT (ORCPT ); Tue, 7 Jul 2009 11:55:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755304AbZGGPzI (ORCPT ); Tue, 7 Jul 2009 11:55:08 -0400 Received: from viefep19-int.chello.at ([62.179.121.39]:40781 "EHLO viefep19-int.chello.at" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754864AbZGGPzH (ORCPT ); Tue, 7 Jul 2009 11:55:07 -0400 X-SourceIP: 213.93.53.227 Subject: Re: [PATCH 1/3] Increase lockdep limits: MAX_STACK_TRACE_ENTRIES From: Peter Zijlstra To: Joao Correia Cc: LKML , =?ISO-8859-1?Q?Am=E9rico?= Wang In-Reply-To: References: <1246980836.9777.5.camel@twins> <1246981444.9777.11.camel@twins> Content-Type: text/plain Date: Tue, 07 Jul 2009 17:55:01 +0200 Message-Id: <1246982101.9777.15.camel@twins> Mime-Version: 1.0 X-Mailer: Evolution 2.26.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2462 Lines: 58 On Tue, 2009-07-07 at 16:50 +0100, Joao Correia wrote: > >> Yes. Anything 2.6.31 forward triggers this immediatly during init > >> process, at random places. > > > > Not on my machines it doesn't.. so I suspect its something weird in > > your .config or maybe due to some hardware you have that I don't that > > triggers different drivers or somesuch. > > I am not the only one reporting this, and it happens, for example, > with a stock .config from a Fedora 11 install. > > It may, of course, be a funny driver interaction yes, but other than > stripping the box piece by piece, how would one go about debugging > this otherwise? One thing to do is stare (or share) at the output of /proc/lockdep_chains and see if there's some particularly large chains in there, or many of the same name or something. /proc/lockdep_stats might also be interesting, mine reads like: [root@opteron ~]# cat /proc/lockdep_stats lock-classes: 641 [max: 8191] direct dependencies: 3794 [max: 16384] indirect dependencies: 7557 all direct dependencies: 73254 dependency chains: 3716 [max: 32768] dependency chain hlocks: 10167 [max: 163840] in-hardirq chains: 21 in-softirq chains: 353 in-process chains: 3342 stack-trace entries: 91035 [max: 262144] combined max dependencies: 26035284 hardirq-safe locks: 28 hardirq-unsafe locks: 460 softirq-safe locks: 114 softirq-unsafe locks: 373 irq-safe locks: 123 irq-unsafe locks: 460 hardirq-read-safe locks: 0 hardirq-read-unsafe locks: 45 softirq-read-safe locks: 8 softirq-read-unsafe locks: 39 irq-read-safe locks: 8 irq-read-unsafe locks: 45 uncategorized locks: 106 unused locks: 1 max locking depth: 14 max recursion depth: 10 debug_locks: 1 -- 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/