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 8FA3EC4320A for ; Sun, 1 Aug 2021 23:45:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 759E3610A6 for ; Sun, 1 Aug 2021 23:45:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231872AbhHAXpl (ORCPT ); Sun, 1 Aug 2021 19:45:41 -0400 Received: from bhuna.collabora.co.uk ([46.235.227.227]:50942 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231877AbhHAXpi (ORCPT ); Sun, 1 Aug 2021 19:45:38 -0400 Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: ezequiel) with ESMTPSA id 93EF11F424CD 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 20:45:05 -0300 Message-Id: <20210801234509.18774-4-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