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,URIBL_BLOCKED, 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 EDFCEC433FF for ; Mon, 12 Aug 2019 08:24:59 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id B96802087B for ; Mon, 12 Aug 2019 08:24:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B96802087B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=mediatek.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 6F4816B0005; Mon, 12 Aug 2019 04:24:59 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 6A4ED6B0006; Mon, 12 Aug 2019 04:24:59 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 5E2996B0008; Mon, 12 Aug 2019 04:24:59 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0136.hostedemail.com [216.40.44.136]) by kanga.kvack.org (Postfix) with ESMTP id 3AB276B0005 for ; Mon, 12 Aug 2019 04:24:59 -0400 (EDT) Received: from smtpin03.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with SMTP id D8EEC8248AA3 for ; Mon, 12 Aug 2019 08:24:58 +0000 (UTC) X-FDA: 75813090276.03.help49_2b4818a8bf755 X-HE-Tag: help49_2b4818a8bf755 X-Filterd-Recvd-Size: 2772 Received: from mailgw01.mediatek.com (unknown [210.61.82.183]) by imf41.hostedemail.com (Postfix) with ESMTP for ; Mon, 12 Aug 2019 08:24:57 +0000 (UTC) X-UUID: e2401d4e653c481e87b5cab55e7c4c14-20190812 X-UUID: e2401d4e653c481e87b5cab55e7c4c14-20190812 Received: from mtkcas08.mediatek.inc [(172.21.101.126)] by mailgw01.mediatek.com (envelope-from ) (Cellopoint E-mail Firewall v4.1.10 Build 0707 with TLS) with ESMTP id 2145448533; Mon, 12 Aug 2019 16:24:48 +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; Mon, 12 Aug 2019 16:24:48 +0800 Received: from [172.21.77.33] (172.21.77.33) by mtkcas07.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1395.4 via Frontend Transport; Mon, 12 Aug 2019 16:24:48 +0800 Message-ID: <1565598290.5872.6.camel@mtkswgap22> Subject: Re: [RFC PATCH v2] mm: slub: print kernel addresses in slub debug messages From: Miles Chen To: Matthew Wilcox CC: Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , , , , , "Tobin C . Harding" , Kees Cook Date: Mon, 12 Aug 2019 16:24:50 +0800 In-Reply-To: <20190809142617.GO5482@bombadil.infradead.org> References: <20190809010837.24166-1-miles.chen@mediatek.com> <20190809024644.GL5482@bombadil.infradead.org> <1565359918.12824.20.camel@mtkswgap22> <20190809142617.GO5482@bombadil.infradead.org> 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000002, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, 2019-08-09 at 07:26 -0700, Matthew Wilcox wrote: > On Fri, Aug 09, 2019 at 10:11:58PM +0800, Miles Chen wrote: > > On Thu, 2019-08-08 at 19:46 -0700, Matthew Wilcox wrote: > > > On Fri, Aug 09, 2019 at 09:08:37AM +0800, miles.chen@mediatek.com wrote: > > > > INFO: Slab 0x(____ptrval____) objects=25 used=10 fp=0x(____ptrval____) > > > > > > ... you don't have any randomness on your platform? > > > > We have randomized base on our platforms. > > Look at initialize_ptr_random(). If you have randomness, then you > get a siphash_1u32() of the address. With no randomness, you get this > ___ptrval___ string instead. > You are right. There is no randomness in this platform. (I ran my test code on Qemu with no randomness) thanks again