Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756895Ab1CIAgu (ORCPT ); Tue, 8 Mar 2011 19:36:50 -0500 Received: from proofpoint-cluster.metrocast.net ([65.175.128.136]:47687 "EHLO proofpoint-cluster.metrocast.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755347Ab1CIAgt (ORCPT ); Tue, 8 Mar 2011 19:36:49 -0500 Subject: Re: BUG at mm/mmap.c:2309 when cx18.ko and cx18-alsa.ko loaded From: Andy Walls To: Hugh Dickins Cc: linux-kernel@vger.kernel.org, akpm@linux-foundation.org, David Miller , linux-media@vger.kernel.org, Devin Heitmueller In-Reply-To: <1299445446.2310.157.camel@localhost> References: <1299204400.2812.35.camel@localhost> <1299362366.2570.27.camel@localhost> <1299377017.2341.50.camel@localhost> <1299445446.2310.157.camel@localhost> Content-Type: text/plain; charset="UTF-8" Date: Tue, 08 Mar 2011 19:37:01 -0500 Message-ID: <1299631021.3023.10.camel@localhost> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 (2.28.3-1.fc12) Content-Transfer-Encoding: 7bit X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:5.2.15,1.0.148,0.0.0000 definitions=2011-03-08_09:2011-03-08,2011-03-08,1970-01-01 signatures=0 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 spamscore=0 ipscore=0 suspectscore=0 phishscore=0 bulkscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx engine=5.0.0-1012030000 definitions=main-1103080182 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2435 Lines: 68 On Sun, 2011-03-06 at 16:04 -0500, Andy Walls wrote: > On Sun, 2011-03-06 at 10:37 -0800, Hugh Dickins wrote: > > > > Thanks for all the effort you are putting into investigating this: you > > deserve a better response than I can give you. > > > > mm/vmalloc.c's vmap_area handling is entirely separate from > > mm/mmap.c's vm_area_struct handling, yet both misbehaviors would be > > explained if a next pointer has been corrupted to NULL. > > > > Probably just coincidence that they both manifest that way, though the > > underlying problem may turn out to be one. > > If you have not already, it would be well worth turning on > > CONFIG_DEBUG_LIST and CONFIG_DEBUG_SLAB or CONFIG_SLUB_DEBUG with > > CONFIG_SLUB_DEBUG_ON. > > > But you are having trouble > > reproducing it yourself? > > I can't say yet. I'm currently two for two. After backing up the machine and testing again, I'm now 3 for 3. This time it happened in the memset() in kernel/module.c:move_module() when modprobe was trying to load the cx18-alsa.ko module. static int move_module(struct module *mod, struct load_info *info) { int i; void *ptr; /* Do the allocs. */ ptr = module_alloc_update_bounds(mod->core_size); /* * The pointer to this block is stored in the module structure * which is inside the block. Just mark it as not being a * leak. */ kmemleak_not_leak(ptr); if (!ptr) return -ENOMEM; memset(ptr, 0, mod->core_size); <----- Ooops/BUG /home/andy/cx18dev/git/media_tree/kernel/module.c:2529 385c: 41 8b 8c 24 64 01 00 mov 0x164(%r12),%ecx 3863: 00 3864: 31 c0 xor %eax,%eax 3866: 48 89 d7 mov %rdx,%rdi 3869: f3 aa rep stos %al,%es:(%rdi) <----- Oops/BUG ptr had a value of 0x0000000000001000 I'm starting a git bisect now. Regards, Andy -- 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/