Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757015AbYFFNeA (ORCPT ); Fri, 6 Jun 2008 09:34:00 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754231AbYFFNdw (ORCPT ); Fri, 6 Jun 2008 09:33:52 -0400 Received: from netops-testserver-3-out.sgi.com ([192.48.171.28]:52377 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753063AbYFFNdv (ORCPT ); Fri, 6 Jun 2008 09:33:51 -0400 Message-ID: <48493CBD.1000202@sgi.com> Date: Fri, 06 Jun 2008 06:33:49 -0700 From: Mike Travis User-Agent: Thunderbird 2.0.0.6 (X11/20070801) MIME-Version: 1.0 To: Vegard Nossum CC: Ingo Molnar , Andrew Morton , Stephen Rothwell , linux-next@vger.kernel.org, LKML Subject: Re: linux-next: Tree for June 5 References: <20080605175217.cee497f3.sfr@canb.auug.org.au> <20080605195604.41623687.akpm@linux-foundation.org> <20080606071707.GB9708@elte.hu> <20080606002957.6329a0ec.akpm@linux-foundation.org> <20080606024811.70db9ab2.akpm@linux-foundation.org> <20080606035413.37f340ef.akpm@linux-foundation.org> <20080606115759.GA29321@elte.hu> <19f34abd0806060533x6d3ff66tc29306143103fc40@mail.gmail.com> In-Reply-To: <19f34abd0806060533x6d3ff66tc29306143103fc40@mail.gmail.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2933 Lines: 77 Vegard Nossum wrote: > On Fri, Jun 6, 2008 at 1:57 PM, Ingo Molnar wrote: >> * Andrew Morton wrote: >> >>> Good >>> >>> a9ad585c8a18f7ba754b85f5786976609b9d7d29 >>> Author: Mike Travis 2008-05-12 12:21:12 >>> Committer: Thomas Gleixner 2008-05-23 09:07:47 >>> Parent: 543e21916497be5a4005fd5820264ce1de9bd56d (x86: restore pda nodenumber field) >>> Child: 78d49c6d890aee9cf8aea371011c9d7b0121b822 (x86: remove static boot_cpu_pda array v2) >>> Branch: >>> Follows: v2.6.26-rc2 >>> Precedes: next-20080526 >>> >>> x86: remove the static 256k node_to_cpumask_map >>> >>> crash, as described earlier. >> thanks for tracking it down! This was the origin of the commit: >> >> # tip/x86/numa: a9ad585: x86: remove the static 256k node_to_cpumask_map >> >> which has been in -tip since May 12 and in linux-next for two weeks >> AFAICS, which is beyond the point of being something freshly wrong. >> >> So i suspect something more subtle here. What compiler version are you >> using? This crash is not something that has been found in testing before >> - i use rather new compilers, gcc 4.2.2 most of the time. Previous >> compilers miscompile the kernel seriously so it's not usable for our >> regression testing grid. >> > > Hi, > > I reproced it with gc 4.1.2. I think the error is somewhere in kernel/sched.c. > > static int __build_sched_domains(const cpumask_t *cpu_map, > struct sched_domain_attr *attr) > { > ... > for (i = 0; i < MAX_NUMNODES; i++) { > ... > sg = kmalloc_node(sizeof(struct sched_group), GFP_KERNEL, i); > ... > > This code is calling into the allocator with a spurious value of i, > which causes SLAB to use an index (of 4 in my case) that is out of > bounds for its nodelist array (at least it hasn't been initialized). > > This bit of code (a bit further down, inside the same loop) is also dubious: > > sg = kmalloc_node(sizeof(struct sched_group), > GFP_KERNEL, i); > if (!sg) { > printk(KERN_WARNING > "Can not alloc domain group for node %d\n", j); > goto error; > } > > Where it passes i to kmalloc_node() but reports an allocation for node > j. Which one is correct? > > Hope this helps, will send an update if I find out more. > > > Vegard > Thanks Vegard for tracking this down. My thoughts were along the same wavelength... ;-) Mike -- 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/