From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753052AbdDKQXd (ORCPT ); Tue, 11 Apr 2017 12:23:33 -0400 Received: from resqmta-ch2-04v.sys.comcast.net ([69.252.207.36]:34888 "EHLO resqmta-ch2-04v.sys.comcast.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751861AbdDKQXa (ORCPT ); Tue, 11 Apr 2017 12:23:30 -0400 Date: Tue, 11 Apr 2017 11:23:28 -0500 (CDT) From: Christoph Lameter X-X-Sender: cl@east.gentwo.org To: Kees Cook cc: Michal Hocko , Andrew Morton , Pekka Enberg , David Rientjes , Joonsoo Kim , Linux-MM , LKML Subject: Re: [PATCH] mm: Add additional consistency check In-Reply-To: Message-ID: References: <20170404113022.GC15490@dhcp22.suse.cz> <20170404151600.GN15132@dhcp22.suse.cz> <20170404194220.GT15132@dhcp22.suse.cz> <20170404201334.GV15132@dhcp22.suse.cz> <20170411134618.GN6729@dhcp22.suse.cz> <20170411141956.GP6729@dhcp22.suse.cz> Content-Type: text/plain; charset=US-ASCII X-CMAE-Envelope: MS4wfJL4JC2dka3LBN+V5wQetQ1sq3U7lN+8WvGXTtUkoTBaE4ZSgF7bT0SjjXQUdDQM4AQLAYfow4oqdBHifBT3CC2ngZHzzZmNwOsdwkh3O2owVjTyLmEA wIKsGAbuuBevc7eEv2s6EeyTEZ/05REzCBLH7H0O/UJu0hxHtk6Palstht8O9MUiXZDQpbb5v2tj46y2RQoHYyQfT3GQa1tHR/3Ck/arKdfUW0VqQQKiC1CP 4p4IGMWdUorVUCLUjkL4+MUS+d8QnwJ4OvIAOiqwtTiptDRuDIBjjbJYQ8T2QanGwYhwaO2OKQHUs0HtKRgSOTsdfMswExPDM42eoT+7WsKHe2qIDT8NOTsb dfjEDgrjMO3o6pVIkhmGAiTPB28GJONoQzYXlxZKpqfCkZGMeJM= Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 11 Apr 2017, Kees Cook wrote: > It seems that enabling the debug checks comes with a non-trivial > performance impact. I'd like to see consistency checks by default so > we can handle intentional heap corruption attacks better. This check > isn't expensive... Its in a very hot code and frequently used code path. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-io0-f197.google.com (mail-io0-f197.google.com [209.85.223.197]) by kanga.kvack.org (Postfix) with ESMTP id D438E6B03A2 for ; Tue, 11 Apr 2017 12:23:30 -0400 (EDT) Received: by mail-io0-f197.google.com with SMTP id f98so4256908iod.18 for ; Tue, 11 Apr 2017 09:23:30 -0700 (PDT) Received: from resqmta-ch2-09v.sys.comcast.net (resqmta-ch2-09v.sys.comcast.net. [2001:558:fe21:29:69:252:207:41]) by mx.google.com with ESMTPS id s141si2343944itb.110.2017.04.11.09.23.30 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 11 Apr 2017 09:23:30 -0700 (PDT) Date: Tue, 11 Apr 2017 11:23:28 -0500 (CDT) From: Christoph Lameter Subject: Re: [PATCH] mm: Add additional consistency check In-Reply-To: Message-ID: References: <20170404113022.GC15490@dhcp22.suse.cz> <20170404151600.GN15132@dhcp22.suse.cz> <20170404194220.GT15132@dhcp22.suse.cz> <20170404201334.GV15132@dhcp22.suse.cz> <20170411134618.GN6729@dhcp22.suse.cz> <20170411141956.GP6729@dhcp22.suse.cz> Content-Type: text/plain; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Kees Cook Cc: Michal Hocko , Andrew Morton , Pekka Enberg , David Rientjes , Joonsoo Kim , Linux-MM , LKML On Tue, 11 Apr 2017, Kees Cook wrote: > It seems that enabling the debug checks comes with a non-trivial > performance impact. I'd like to see consistency checks by default so > we can handle intentional heap corruption attacks better. This check > isn't expensive... Its in a very hot code and frequently used code path. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org