From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932669AbWKOJel (ORCPT ); Wed, 15 Nov 2006 04:34:41 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932822AbWKOJel (ORCPT ); Wed, 15 Nov 2006 04:34:41 -0500 Received: from mx2.mail.elte.hu ([157.181.151.9]:34224 "EHLO mx2.mail.elte.hu") by vger.kernel.org with ESMTP id S932669AbWKOJek (ORCPT ); Wed, 15 Nov 2006 04:34:40 -0500 Date: Wed, 15 Nov 2006 10:33:54 +0100 From: Ingo Molnar To: Andrew Morton Cc: Stephen Hemminger , linux-kernel@vger.kernel.org Subject: Re: sleeping functions called in invalid context during resume Message-ID: <20061115093354.GA30813@elte.hu> References: <20061114223002.10c231bd@localhost.localdomain> <20061115012025.13c72fc1.akpm@osdl.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20061115012025.13c72fc1.akpm@osdl.org> User-Agent: Mutt/1.4.2.2i X-ELTE-SpamScore: -4.4 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-4.4 required=5.9 tests=ALL_TRUSTED,AWL,BAYES_00 autolearn=no SpamAssassin version=3.0.3 -3.3 ALL_TRUSTED Did not pass through any untrusted hosts -2.6 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0004] 1.5 AWL AWL: From: address is in the auto white-list X-ELTE-VirusStatus: clean Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org * Andrew Morton wrote: > > [] vfs_write+0xce/0x174 > > [] sys_write+0x45/0x6e > > [] system_call+0x7e/0x83 > > DWARF2 unwinder stuck at system_call+0x7e/0x83 > > > > Leftover inexact backtrace: > > Could mean that someone somewhere forgot to release a spinlock. > > Ingo had a patch which would find the culprit (preempt-tracing.patch). > > Does it still live? if it's really a spinlock/rwlock release that was missed, then i've got good news: we already have that debugging infrastructure, it's called lockdep :-) The patch below makes use of that capability of lockdep for all stackdumps that are printed to the console. Stephen, please apply this patch, enable CONFIG_PROVE_LOCKING and try to trigger another message. Ingo ----------------> Subject: lockdep: show held locks when showing a stackdump From: Ingo Molnar show held locks when printing a backtrace. Signed-off-by: Ingo Molnar --- arch/i386/kernel/traps.c | 1 + arch/x86_64/kernel/traps.c | 1 + 2 files changed, 2 insertions(+) Index: linux/arch/i386/kernel/traps.c =================================================================== --- linux.orig/arch/i386/kernel/traps.c +++ linux/arch/i386/kernel/traps.c @@ -318,6 +318,7 @@ static void show_stack_log_lvl(struct ta } printk("\n%sCall Trace:\n", log_lvl); show_trace_log_lvl(task, regs, esp, log_lvl); + debug_show_held_locks(task); } void show_stack(struct task_struct *task, unsigned long *esp) Index: linux/arch/x86_64/kernel/traps.c =================================================================== --- linux.orig/arch/x86_64/kernel/traps.c +++ linux/arch/x86_64/kernel/traps.c @@ -405,6 +405,7 @@ show_trace(struct task_struct *tsk, stru printk("\nCall Trace:\n"); dump_trace(tsk, regs, stack, &print_trace_ops, NULL); printk("\n"); + debug_show_held_locks(tsk); } static void