From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755220AbZHYQoh (ORCPT ); Tue, 25 Aug 2009 12:44:37 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754875AbZHYQog (ORCPT ); Tue, 25 Aug 2009 12:44:36 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:50519 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754789AbZHYQog (ORCPT ); Tue, 25 Aug 2009 12:44:36 -0400 Date: Tue, 25 Aug 2009 09:43:47 -0700 (PDT) From: Linus Torvalds X-X-Sender: torvalds@localhost.localdomain To: "Mikko C." cc: Eric Paris , Frans Pop , linux-kernel@vger.kernel.org, zdenek.kabelac@gmail.com, christoph.thielecke@gmx.de, akpm@linux-foundation.org, viro@zeniv.linux.org.uk, grant.wilson@zen.co.uk Subject: Re: [PATCH 2/3] inotify: do not BUG on idr entries at inotify destruction In-Reply-To: <4A93CE2A.90509@gmail.com> Message-ID: References: <20090824173524.14196.25992.stgit@paris.rdu.redhat.com> <20090824173524.14196.25992.stgit@paris.rdu.redhat.com> <20090824173812.14196.381.stgit@paris.rdu.redhat.com> <200908242034.50885.elendil@planet.nl> <1251140949.25096.16.camel@dhcp231-106.rdu.redhat.com> <1251146166.25096.22.camel@dhcp231-106.rdu.redhat.com> <4A93CE2A.90509@gmail.com> User-Agent: Alpine 2.01 (LFD 1184 2008-12-16) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 25 Aug 2009, Mikko C. wrote: > > I just got this with -rc7, but it doesn't look related to what I was having > before: > > BUG: Bad page map in process kio_thumbnail pte:ffff88006cc99128 pmd:6d3b1067 > addr:00007f9d4e3a5000 vm_flags:08000070 anon_vma:(null) > mapping:ffff88007abe21a0 index:200 > vma->vm_ops->fault: filemap_fault+0x0/0x460 > vma->vm_file->f_op->mmap: ext4_file_mmap+0x0/0x80 > Pid: 28022, comm: kio_thumbnail Not tainted 2.6.31-rc7 #1 > Call Trace: > [] ? print_bad_pte+0x1d4/0x2c0 > [] ? vm_normal_page+0x99/0xa0 > [] ? unmap_vmas+0x4cd/0x970 > [] ? exit_mmap+0x104/0x1d0 > [] ? mmput+0x4d/0x100 > [] ? exit_mm+0x101/0x150 > [] ? do_exit+0x6c0/0x750 > [] ? do_group_exit+0x56/0xd0 > [] ? sys_exit_group+0x22/0x40 > [] ? system_call_fastpath+0x16/0x1b > Disabling lock debugging due to kernel taint > > No lockups or anything. That looks like a memory corruption bug. Your page table entry is bad: pte:ffff88006cc99128. It has the "special" bit set (one of the software bits), in a mapping that should not have special pages. But that pte entry is odd in other ways too - it's _PAGE_PROTNONE, which is unusual (but not necessarily _wrong_) and _PAGE_BIT_ACCESSED. And it has the high bits set, which is really not ok for a page table entry. The PTE entry should look more like the pmd entry. So it looks like the pte has been overwritten by some bogus value, presumably by a stale pointer. And it migth be related to your inotify problems that way. Linus