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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,USER_AGENT_GIT autolearn=ham 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 2DC1DC4338F for ; Sun, 1 Aug 2021 23:45:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 14BD361042 for ; Sun, 1 Aug 2021 23:45:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232096AbhHAXp5 (ORCPT ); Sun, 1 Aug 2021 19:45:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36226 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231958AbhHAXpw (ORCPT ); Sun, 1 Aug 2021 19:45:52 -0400 Received: from bhuna.collabora.co.uk (bhuna.collabora.co.uk [IPv6:2a00:1098:0:82:1000:25:2eeb:e3e3]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3A36BC06175F for ; Sun, 1 Aug 2021 16:45:44 -0700 (PDT) Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: ezequiel) with ESMTPSA id 9A6121F424D4 From: Ezequiel Garcia To: linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org, Richard Weinberger Cc: Miquel Raynal , Vignesh Raghavendra , Ezequiel Garcia Subject: [PATCH 3/3] mtdblock: Warn if the added for a NAND device Date: Sun, 1 Aug 2021 20:45:09 -0300 Message-Id: <20210801234509.18774-8-ezequiel@collabora.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210801234509.18774-1-ezequiel@collabora.com> References: <20210801234509.18774-1-ezequiel@collabora.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org There is a surprisingly large number of tutorials that suggest using mtdblock to mount SquashFS filesystems on flash devices, including NAND devices. This approach is suboptimal than using UBI. If the flash device is NAND, this is specially true, due to wear leveling, bit-flips and badblocks. In this case UBI is strongly preferred, so be nice to users and print a warning suggesting to consider UBI block, if mtdblock is added for a NAND device. Signed-off-by: Ezequiel Garcia Untracked files not listed --- drivers/mtd/mtdblock.c | 4 ++++ drivers/mtd/mtdblock_ro.c | 4 ++++ 2 files changed, 8 insertions(+) diff --git a/drivers/mtd/mtdblock.c b/drivers/mtd/mtdblock.c index b2d5ed1cbc94..7c02643f862f 100644 --- a/drivers/mtd/mtdblock.c +++ b/drivers/mtd/mtdblock.c @@ -332,6 +332,10 @@ static void mtdblock_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd) if (!(mtd->flags & MTD_WRITEABLE)) dev->mbd.readonly = 1; + if (mtd_type_is_nand(mtd)) + pr_warn("%s: MTD device '%s' is NAND, please consider using UBI block devices instead.\n", + tr->name, mtd->name); + if (add_mtd_blktrans_dev(&dev->mbd)) kfree(dev); } diff --git a/drivers/mtd/mtdblock_ro.c b/drivers/mtd/mtdblock_ro.c index fb5dc89369de..a438e2f6089c 100644 --- a/drivers/mtd/mtdblock_ro.c +++ b/drivers/mtd/mtdblock_ro.c @@ -60,6 +60,10 @@ static void mtdblock_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd) dev->tr = tr; dev->readonly = 1; + if (mtd_type_is_nand(mtd)) + pr_warn("%s: MTD device '%s' is NAND, please consider using UBI block devices instead.\n", + tr->name, mtd->name); + if (add_mtd_blktrans_dev(dev)) kfree(dev); } -- 2.32.0