From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756269Ab2INWNs (ORCPT ); Fri, 14 Sep 2012 18:13:48 -0400 Received: from mail-wi0-f178.google.com ([209.85.212.178]:64664 "EHLO mail-wi0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754454Ab2INWNq (ORCPT ); Fri, 14 Sep 2012 18:13:46 -0400 Message-ID: <5053AC2F.3070203@gmail.com> Date: Sat, 15 Sep 2012 00:14:07 +0200 From: Sasha Levin User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:15.0) Gecko/20120902 Thunderbird/15.0 MIME-Version: 1.0 To: Michel Lespinasse CC: linux-mm@kvack.org, riel@redhat.com, peterz@infradead.org, aarcange@redhat.com, hughd@google.com, daniel.santos@pobox.com, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, Dave Jones Subject: Re: [PATCH 6/7] mm: add CONFIG_DEBUG_VM_RB build option References: <1346750457-12385-1-git-send-email-walken@google.com> <1346750457-12385-7-git-send-email-walken@google.com> In-Reply-To: <1346750457-12385-7-git-send-email-walken@google.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 On 09/04/2012 11:20 AM, Michel Lespinasse wrote: > Add a CONFIG_DEBUG_VM_RB build option for the previously existing > DEBUG_MM_RB code. Now that Andi Kleen modified it to avoid using > recursive algorithms, we can expose it a bit more. > > Also extend this code to validate_mm() after stack expansion, and to > check that the vma's start and last pgoffs have not changed since the > nodes were inserted on the anon vma interval tree (as it is important > that the nodes be reindexed after each such update). This patch exposes the following warning: [ 24.977502] ------------[ cut here ]------------ [ 24.979089] WARNING: at mm/interval_tree.c:110 anon_vma_interval_tree_verify+0x81/0xa0() [ 24.981765] Pid: 5928, comm: trinity-child37 Tainted: G W 3.6.0-rc5-next-20120914-sasha-00003-g7deb7fa-dirty #333 [ 24.985501] Call Trace: [ 24.986345] [] ? anon_vma_interval_tree_verify+0x81/0xa0 [ 24.988535] [] warn_slowpath_common+0x86/0xb0 [ 24.990636] [] warn_slowpath_null+0x15/0x20 [ 24.992658] [] anon_vma_interval_tree_verify+0x81/0xa0 [ 24.994980] [] validate_mm+0x58/0x1e0 [ 24.996772] [] vma_link+0x94/0xe0 [ 24.997719] [] copy_vma+0x279/0x2e0 [ 24.998522] [] ? trace_hardirqs_off+0xd/0x10 [ 25.000772] [] move_vma+0xa9/0x260 [ 25.002499] [] sys_mremap+0x475/0x540 [ 25.004364] [] tracesys+0xe1/0xe6 [ 25.006108] ---[ end trace 7c901670963aa6e2 ]--- The code line is WARN_ON_ONCE(node->cached_vma_last != avc_last_pgoff(node));