Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753797AbaJBDvy (ORCPT ); Wed, 1 Oct 2014 23:51:54 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:43955 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751357AbaJBDvx (ORCPT ); Wed, 1 Oct 2014 23:51:53 -0400 Message-ID: <542CCBCB.9000709@oracle.com> Date: Wed, 01 Oct 2014 23:51:39 -0400 From: Sasha Levin User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.0 MIME-Version: 1.0 To: Andrew Morton CC: linux-kernel@vger.kernel.org, linux-mm@kvack.org, hughd@google.com, mgorman@suse.de Subject: Re: [PATCH 0/5] mm: poison critical mm/ structs References: <1412041639-23617-1-git-send-email-sasha.levin@oracle.com> <20141001140725.fd7f1d0cf933fbc2aa9fc1b1@linux-foundation.org> <542C749B.1040103@oracle.com> <20141001144834.ff3ff0349951df734d159fb3@linux-foundation.org> In-Reply-To: <20141001144834.ff3ff0349951df734d159fb3@linux-foundation.org> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit X-Source-IP: ucsinet22.oracle.com [156.151.31.94] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/01/2014 05:48 PM, Andrew Morton wrote: > On Wed, 01 Oct 2014 17:39:39 -0400 Sasha Levin wrote: > >>> It looks fairly cheap - I wonder if it should simply fall under >>> CONFIG_DEBUG_VM rather than the new CONFIG_DEBUG_VM_POISON. >> >> Config options are cheap as well :) > > Thing is, lots of people are enabling CONFIG_DEBUG_VM, but a smaller > number of people will enable CONFIG_DEBUG_VM_POISON. Less coverage. > > Defaulting to y if CONFIG_DEBUG_VM might help, but if people do `make > oldconfig' when CONFIG_DEBUG_VM=n, their CONFIG_DEBUG_VM_POISON will > get set to `n' and will remain that way when they set CONFIG_DEBUG_VM > again. In that case, what about: diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index db41b15..b2c7038 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -546,6 +546,7 @@ config DEBUG_VM_RB config DEBUG_VM_POISON bool "Poison VM structures" depends on DEBUG_VM + def_bool y help Add poison to the beggining and end of various VM structure to detect memory corruption in VM management code. We'll default to "Y" in 'make oldconfig' and it'll automatically be switched on when the user selects CONFIG_DEBUG_VM=y, but we still keep the advantages of having it in a different config option. Thanks, Sasha -- 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/