From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754290AbZCSRCU (ORCPT ); Thu, 19 Mar 2009 13:02:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756185AbZCSRCF (ORCPT ); Thu, 19 Mar 2009 13:02:05 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:36458 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755411AbZCSRCE (ORCPT ); Thu, 19 Mar 2009 13:02:04 -0400 Date: Thu, 19 Mar 2009 18:01:30 +0100 From: Ingo Molnar To: Jeremy Fitzhardinge Cc: Rusty Russell , Andrew Morton , Steven Rostedt , LKML , Peter Zijlstra Subject: Re: [PATCH] cpumask: remove cpumask allocation from idle_balance Message-ID: <20090319170130.GA29683@elte.hu> References: <200903191522.21045.rusty@rustcorp.com.au> <200903192310.52314.rusty@rustcorp.com.au> <20090319132426.GA27017@elte.hu> <20090319162942.GA21672@elte.hu> <49C278F2.1000600@goop.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <49C278F2.1000600@goop.org> User-Agent: Mutt/1.5.18 (2008-05-17) 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 * Jeremy Fitzhardinge wrote: > Ingo Molnar wrote: >> * Ingo Molnar wrote: >> >> >>>> This time for sure, >>>> >>> not so sure: >>> >>> [ 4.303068] ============================================================================= >>> [ 4.303332] BUG idr_layer_cache: Redzone overwritten >>> [ 4.303332] ----------------------------------------------------------------------------- >>> [ 4.303332] [ 4.303332] INFO: >>> 0xffff88003f838958-0xffff88003f83895f. First byte 0xa1 instead of >>> 0xbb >>> [ 4.303332] INFO: Allocated in 0xffff88003f9b94b0 age=4294878587 cpu=2 pid=0 >>> [ 4.303332] INFO: Freed in 0xffff88003f8389f0 age=18446744073709463001 cpu=4294967295 pid=0 >>> [ 4.303332] INFO: Slab 0xffffe200015d5340 objects=13 used=10 fp=0xffff88003f838738 flags=0x40000000000020c3 >>> [ 4.303332] INFO: Object 0xffff88003f838738 @offset=1848 fp=0x(null) >>> >> >> hm, i'm seeing this even with the cpus4096 bits removed. >> >> It _seems_ to trigger when i add these two commits: >> >> 71ff49d: x86: with the last user gone, remove set_pte_present >> b40c757: x86/32: no need to use set_pte_present in set_pte_vaddr >> >> but i'm not completely sure it's related, i tried a bisection and it >> showed heisenbug properties. >> >> Might have come from upstream, that saw some IDR changes recently. >> > > Seems very unlikely; those patches only touch 32-bit only code, > and this looks like a 64-bit crash. yes - that's why i think it's a Heisenbug. Ingo