Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755578AbYARJOz (ORCPT ); Fri, 18 Jan 2008 04:14:55 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753622AbYARJOl (ORCPT ); Fri, 18 Jan 2008 04:14:41 -0500 Received: from mx3.mail.elte.hu ([157.181.1.138]:34354 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753013AbYARJOj (ORCPT ); Fri, 18 Jan 2008 04:14:39 -0500 Date: Fri, 18 Jan 2008 10:14:22 +0100 From: Ingo Molnar To: Zan Lynx Cc: Andrew Morton , Linux Kernel , Peter Zijlstra Subject: Re: 2.6.24-rc8-mm1 and boot lockup during locking self-test Message-ID: <20080118091422.GF24337@elte.hu> References: <1200612743.7660.8.camel@localhost> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1200612743.7660.8.camel@localhost> User-Agent: Mutt/1.5.17 (2007-11-01) X-ELTE-VirusStatus: clean 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=3.2.3 -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 Content-Length: 2807 Lines: 94 * Zan Lynx wrote: > Included Ingo in CC because I think he did the locking test. > > The following is copied from a different boot, but looks the same to my > eye as what I got on the console: > > ------------------------ > | Locking API testsuite: > ---------------------------------------------------------------------------- > | spin |wlock |rlock |mutex | wsem | rsem | > -------------------------------------------------------------------------- > A-A deadlock: ok | > > It just sticks there. I assume that means a problem with wlock? does the patch below from Nick fix it? It went upstream just after rc8-mm1 so rc8-mm1 might be missing it. Ingo ------------------> commit 5a26db5bd25cf4bf32ae9fa9f6136b6b6d5b45c5 Author: Nick Piggin Date: Wed Jan 16 09:51:58 2008 +0100 lockdep: fix internal double unlock during self-test Lockdep, during self-test (when it was simulating double unlocks) was sometimes unconditionally unlocking a spinlock when it had not been locked. This won't work for ticket locks. Signed-off-by: Nick Piggin Signed-off-by: Ingo Molnar Signed-off-by: Peter Zijlstra diff --git a/kernel/lockdep.c b/kernel/lockdep.c index 723bd9f..4335f12 100644 --- a/kernel/lockdep.c +++ b/kernel/lockdep.c @@ -2943,9 +2943,10 @@ void lockdep_free_key_range(void *start, unsigned long size) struct list_head *head; unsigned long flags; int i; + int locked; raw_local_irq_save(flags); - graph_lock(); + locked = graph_lock(); /* * Unhash all classes that were created by this module: @@ -2959,7 +2960,8 @@ void lockdep_free_key_range(void *start, unsigned long size) zap_class(class); } - graph_unlock(); + if (locked) + graph_unlock(); raw_local_irq_restore(flags); } @@ -2969,6 +2971,7 @@ void lockdep_reset_lock(struct lockdep_map *lock) struct list_head *head; unsigned long flags; int i, j; + int locked; raw_local_irq_save(flags); @@ -2987,7 +2990,7 @@ void lockdep_reset_lock(struct lockdep_map *lock) * Debug check: in the end all mapped classes should * be gone. */ - graph_lock(); + locked = graph_lock(); for (i = 0; i < CLASSHASH_SIZE; i++) { head = classhash_table + i; if (list_empty(head)) @@ -3000,7 +3003,8 @@ void lockdep_reset_lock(struct lockdep_map *lock) } } } - graph_unlock(); + if (locked) + graph_unlock(); out_restore: raw_local_irq_restore(flags); -- 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/