From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752061AbZHXJ2u (ORCPT ); Mon, 24 Aug 2009 05:28:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751286AbZHXJ2t (ORCPT ); Mon, 24 Aug 2009 05:28:49 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:39201 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750859AbZHXJ2s (ORCPT ); Mon, 24 Aug 2009 05:28:48 -0400 Date: Mon, 24 Aug 2009 11:28:36 +0200 From: Ingo Molnar To: "Paul E. McKenney" Cc: mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, tglx@linutronix.de, linux-tip-commits@vger.kernel.org Subject: Re: [tip:core/rcu] rcu: Consolidate sparse and lockdep declarations in include/linux/rcupdate.h Message-ID: <20090824092836.GB25267@elte.hu> References: <20090823184202.GA20404@elte.hu> <20090823193356.GB6882@linux.vnet.ibm.com> <20090823225321.GA3976@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090823225321.GA3976@linux.vnet.ibm.com> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.5 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Paul E. McKenney wrote: > On Sun, Aug 23, 2009 at 12:33:56PM -0700, Paul E. McKenney wrote: > > On Sun, Aug 23, 2009 at 08:42:02PM +0200, Ingo Molnar wrote: > > > > > > * tip-bot for Paul E. McKenney wrote: > > > > > > > Commit-ID: bc33f24bdca8b6e97376e3a182ab69e6cdefa989 > > > > Gitweb: http://git.kernel.org/tip/bc33f24bdca8b6e97376e3a182ab69e6cdefa989 > > > > Author: Paul E. McKenney > > > > AuthorDate: Sat, 22 Aug 2009 13:56:47 -0700 > > > > Committer: Ingo Molnar > > > > CommitDate: Sun, 23 Aug 2009 10:32:37 +0200 > > > > > > > > rcu: Consolidate sparse and lockdep declarations in include/linux/rcupdate.h > > > > > > -tip testing found a spontaneous reboot crash, which i > > > bisected back to this commit: > > > > > > bc33f24bdca8b6e97376e3a182ab69e6cdefa989 is first bad commit > > > > > > the reboot happens during the ftrace syscall tracepoints > > > self-test: > > > > > > [ 34.618832] Testing event sys_exit_set_robust_list: OK > > > [ 34.635511] Testing event sys_enter_get_robust_list: OK > > > [ 34.652164] Testing event sys_exit_get_robust_list: OK > > > [ 34.668844] Testing event sys_enter_futex: OK > > > [ 34.685495] Testing event sys_exit_futex: OK > > > [ 34.702170] Testing event lock_acquire: [instant reboot] > > > > > > There's no log message - just a reboot - which signals some > > > severe crash - perhaps some locking related infinite > > > recursion or something like that? > > > > Pretty impressive for having mostly moved RCU's lockdep-related > > declarations from one file to another... :-/ > > > > Looking into it, probably a typo on my part. > > I rechecked this several times, and don't see how anything else > should have noticed this patch. That said, that self-test is > rather amazing code, so... What do you think about the infinite recursion bug that Lai Jiangshan's found in that patch? (sharp eyes really!) That might explain the crash -tip testing found. Ingo