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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BFDBBC001E0 for ; Mon, 23 Oct 2023 07:36:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233517AbjJWHgv (ORCPT ); Mon, 23 Oct 2023 03:36:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48148 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233529AbjJWHgr (ORCPT ); Mon, 23 Oct 2023 03:36:47 -0400 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 26ED7D66 for ; Mon, 23 Oct 2023 00:36:44 -0700 (PDT) Received: from kwepemm000013.china.huawei.com (unknown [172.30.72.55]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4SDRhl5q81zcdJs; Mon, 23 Oct 2023 15:31:51 +0800 (CST) Received: from [10.174.178.46] (10.174.178.46) by kwepemm000013.china.huawei.com (7.193.23.81) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.31; Mon, 23 Oct 2023 15:36:41 +0800 Subject: Re: [PATCH v2] ubi: gluebi: Fix NULL pointer dereference caused by ftl notifier To: Richard Weinberger CC: ZhaoLong Wang , Miquel Raynal , Vignesh Raghavendra , dpervushin , Artem Bityutskiy , linux-mtd , linux-kernel , yi zhang , yangerkun References: <20231018121618.778385-1-wangzhaolong1@huawei.com> <1381458025.20897.1697747248632.JavaMail.zimbra@nod.at> <891e554b-c133-6378-3a65-836fc9147e54@huawei.com> <441107100.23734.1697904580252.JavaMail.zimbra@nod.at> <93b2d5ab-e36c-be08-7343-ef4ca16f991d@huawei.com> <879960555.29268.1698045341596.JavaMail.zimbra@nod.at> From: Zhihao Cheng Message-ID: <12400272-4449-040c-1ccd-6494a67f4da0@huawei.com> Date: Mon, 23 Oct 2023 15:36:29 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.5.0 MIME-Version: 1.0 In-Reply-To: <879960555.29268.1698045341596.JavaMail.zimbra@nod.at> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 8bit X-Originating-IP: [10.174.178.46] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To kwepemm000013.china.huawei.com (7.193.23.81) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 在 2023/10/23 15:15, Richard Weinberger 写道: > ----- Ursprüngliche Mail ----- >> Von: "chengzhihao1" >>>> If we add new ioctls to control creation/destroying of gluebi, then >>>> gluebi mtd won't be automatically created when UBI volume is added. I'm >>>> not certain whether this change will effect existing startup process >>>> that depends on gluebi. >>> Let's take a stack back. The sole purpose of gluebi is providing >>> a way to run JFFS2 on top of UBI. >> Is it possible that someone runs ext4 on mtdblock based on gluebi, for >> the advantage of wear-leveling? > Unless they want to kill their NAND immediately, no. > UBIblock hat initially an RW-Mode but it was rejected because > UBI is not an FTL and will all dangerous setups. > > What I'm trying to say is, I'd like to avoid adding complicated solutions > or workarounds just to make artificial stacking of outdated MTD components > possible. > Let's keep the big picture in mind. Makes sense. Zhaolong and I didn't make clear the boundary between FTL and ubiblock/gluebi. Now, I believe that UBI needn't be responsible much for the extension mechanism(eg. mtdblock based on gluebi). So, let's pick your solution. > Thanks, > //richard > > .