Received: by 2002:a05:6a10:c7c6:0:0:0:0 with SMTP id h6csp1207674pxy; Sun, 1 Aug 2021 16:48:48 -0700 (PDT) X-Google-Smtp-Source: ABdhPJxtBEvR7qqvnpxLksAmxS1yJW4yutxxGumAaJU2/RSuUUv7NT19Ybs6gG3qZ1qFxighAE1n X-Received: by 2002:aa7:c9d8:: with SMTP id i24mr16191791edt.79.1627861728211; Sun, 01 Aug 2021 16:48:48 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1627861728; cv=none; d=google.com; s=arc-20160816; b=T+Nel5vfU9CExOBoe4+9KFUqBAq6wHtZs7P/vlsCe4hB6964WW4hDR2QnUNCwZO8ZR /QweE+O1CrCDFuXI29Gh58ltJcXs8DLFVUDJc3RpQrFBANlro6ow0RLJ8MyFBs7MRXXc 5JbslMeCp+uX6FcXFmV0KuzEsZ7jgr1OUyU6FhnsyjfBh0cNkmIb4ThOxYeUbM5lAqS9 AUZz6PMhmOrwgSIaAANXo8pQGmfDCW+qPKjx4UKjP/ocTgJba+XTqT9xhJnfxFR+AsJk x1MfGMeumcGe6Tco9z6Wl5YXczpBHga2pguxZvF+e3lfUt5XAY+K1PbjiOvAI8517664 Qwrg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from; bh=TyTxkPd57NcQ9kmri/AuLfFck0jCFPb7Pitk1sOs+UY=; b=EjEbjVHK3n3PQK9ec+3MmNHlwF6byhyyxKMbvpyy0fo2XUPWM4Nzvuj0orYTWiYqJM gNVLYkvRsHp28Fy1/l8brYMaIsoUsyu5j9xfQYebtmW7PTh016no1dZYFswhEXPzc3+8 AxytaapYCVKxmakEgJT/p7ZtoYWs7oz339jSJlUj6AenfuVCCIuusQIAaQ7GD5oUOx6O UfyBDJPVh7l06XOEU/3hCSs0o2w9nHwoICkU6jDcvQ3CP0JML2Y4+CcisSXF66GDiXlJ taX5OXaus4bP2gqyw/xTBKIkUmBEntKkpT/qCZZPm9TS6pAzSUTnIa6QKD4IK4mwU3iW KHtg== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=collabora.com Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id 8si9166305ejx.341.2021.08.01.16.48.25; Sun, 01 Aug 2021 16:48:48 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=collabora.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232043AbhHAXpw (ORCPT + 99 others); Sun, 1 Aug 2021 19:45:52 -0400 Received: from bhuna.collabora.co.uk ([46.235.227.227]:50972 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231899AbhHAXpt (ORCPT ); Sun, 1 Aug 2021 19:45:49 -0400 Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: ezequiel) with ESMTPSA id 700991F41069 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 2/3] mtdblock: Add comment about UBI block devices Date: Sun, 1 Aug 2021 20:45:08 -0300 Message-Id: <20210801234509.18774-7-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. Given this approach is suboptimal than using UBI, and given the UBI block device layer was introduced many years ago specifically with this use case in mind, add a small comment inviting users and developers to consider UBI block. Signed-off-by: Ezequiel Garcia --- drivers/mtd/Kconfig | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/mtd/Kconfig b/drivers/mtd/Kconfig index 32bed6c63863..91cdbbd44317 100644 --- a/drivers/mtd/Kconfig +++ b/drivers/mtd/Kconfig @@ -151,6 +151,9 @@ config MTD_BLOCK_RO You do not need this option for use with the DiskOnChip devices. For those, enable NFTL support (CONFIG_NFTL) instead. +comment "Note that in some cases UBI block is preferred. See MTD_UBI_BLOCK." + depends on MTD_BLOCK || MTD_BLOCK_RO + config FTL tristate "FTL (Flash Translation Layer) support" depends on BLOCK -- 2.32.0