From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,USER_AGENT_SANE_2 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C8392C3A59E for ; Thu, 5 Sep 2019 01:54:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9F39A2168B for ; Thu, 5 Sep 2019 01:54:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730695AbfIEByp (ORCPT ); Wed, 4 Sep 2019 21:54:45 -0400 Received: from mailgw02.mediatek.com ([210.61.82.184]:26599 "EHLO mailgw02.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1727156AbfIEByp (ORCPT ); Wed, 4 Sep 2019 21:54:45 -0400 X-UUID: e1c814d6fac6479dbb5a3b406a2fee58-20190905 X-UUID: e1c814d6fac6479dbb5a3b406a2fee58-20190905 Received: from mtkmrs01.mediatek.inc [(172.21.131.159)] by mailgw02.mediatek.com (envelope-from ) (Cellopoint E-mail Firewall v4.1.10 Build 0809 with TLS) with ESMTP id 1846864118; Thu, 05 Sep 2019 09:54:37 +0800 Received: from mtkcas07.mediatek.inc (172.21.101.84) by mtkmbs07n2.mediatek.inc (172.21.101.141) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Thu, 5 Sep 2019 09:54:34 +0800 Received: from [172.21.84.99] (172.21.84.99) by mtkcas07.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1395.4 via Frontend Transport; Thu, 5 Sep 2019 09:54:34 +0800 Message-ID: <1567648476.32522.36.camel@mtksdccf07> Subject: Re: [PATCH 1/2] mm/kasan: dump alloc/free stack for page allocator From: Walter Wu To: Qian Cai CC: Dmitry Vyukov , Matthias Brugger , Andrew Morton , "Martin Schwidefsky" , Arnd Bergmann , kasan-dev , Linux Memory Management List , LKML , Linux ARM , , , Alexander Potapenko , "Andrey Ryabinin" Date: Thu, 5 Sep 2019 09:54:36 +0800 In-Reply-To: <1567607824.5576.77.camel@lca.pw> References: <20190904065133.20268-1-walter-zh.wu@mediatek.com> <1567606591.32522.21.camel@mtksdccf07> <1567607824.5576.77.camel@lca.pw> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3-0ubuntu6 Content-Transfer-Encoding: 7bit MIME-Version: 1.0 X-MTK: N Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2019-09-04 at 10:37 -0400, Qian Cai wrote: > On Wed, 2019-09-04 at 22:16 +0800, Walter Wu wrote: > > On Wed, 2019-09-04 at 15:44 +0200, Andrey Konovalov wrote: > > > On Wed, Sep 4, 2019 at 8:51 AM Walter Wu wrote: > > > > +config KASAN_DUMP_PAGE > > > > + bool "Dump the page last stack information" > > > > + depends on KASAN && PAGE_OWNER > > > > + help > > > > + By default, KASAN doesn't record alloc/free stack for page > > > > allocator. > > > > + It is difficult to fix up page use-after-free issue. > > > > + This feature depends on page owner to record the last stack of > > > > page. > > > > + It is very helpful for solving the page use-after-free or out- > > > > of-bound. > > > > > > I'm not sure if we need a separate config for this. Is there any > > > reason to not have this enabled by default? > > > > PAGE_OWNER need some memory usage, it is not allowed to enable by > > default in low RAM device. so I create new feature option and the person > > who wants to use it to enable it. > > Or you can try to look into reducing the memory footprint of PAGE_OWNER to fit > your needs. It does not always need to be that way. Thanks your suggestion. We can try to think what can be slimmed. Thanks. Walter