From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759506AbXGEIoA (ORCPT ); Thu, 5 Jul 2007 04:44:00 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758115AbXGEInl (ORCPT ); Thu, 5 Jul 2007 04:43:41 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:49546 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757446AbXGEInj (ORCPT ); Thu, 5 Jul 2007 04:43:39 -0400 Date: Thu, 5 Jul 2007 10:43:23 +0200 From: Ingo Molnar To: Oleg Nesterov Cc: Johannes Berg , Ingo Molnar , Arjan van de Ven , Linux Kernel list , linux-wireless , Peter Zijlstra , Thomas Sattler Subject: Re: [RFC/PATCH] debug workqueue deadlocks with lockdep Message-ID: <20070705084323.GB2447@elte.hu> References: <1182969638.4769.56.camel@johannes.berg> <1183048429.4089.1.camel@johannes.berg> <1183052001.4089.2.camel@johannes.berg> <1183190728.7932.43.camel@earth4> <20070630114658.GA344@tv-sign.ru> <1183381393.4089.117.camel@johannes.berg> <20070703173112.GA108@tv-sign.ru> <1183549772.3812.10.camel@johannes.berg> <20070704125219.GA98@tv-sign.ru> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070704125219.GA98@tv-sign.ru> User-Agent: Mutt/1.5.14 (2007-02-12) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.0 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.0.3 -1.0 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org * Oleg Nesterov wrote: > > > Isn't it better to call lock_release() with nested == 1 ? > > > > Not sure, Ingo? > > Ingo, could you also explain the meaning of "nested" parameter? Looks > like it is just unneeded, lock_release_nested() does a quick check and > use lock_release_non_nested() when hlock is not on top of stack. hm, i forgot about that. We basically turned off all bad-nesting warnings in lockdep due to false positives. the workqueue dependencies should all nest perfectly so please just use nested==1, even though it's a dummy right now. We might want to turn unlock-nest checking back on in the future. Or we'll remove that parameter altogether. Ingo