Received: by 2002:a05:6a10:c7c6:0:0:0:0 with SMTP id h6csp1206751pxy; Sun, 1 Aug 2021 16:47:11 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwDIvx7oXp1V5Y2YOowRpWRpSMka7NRk94q8auaMaH5AYPjydl6pJmDa6sWZPpAflNZSa1M X-Received: by 2002:a17:906:4784:: with SMTP id cw4mr12776209ejc.160.1627861631606; Sun, 01 Aug 2021 16:47:11 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1627861631; cv=none; d=google.com; s=arc-20160816; b=r4D+KMPYbRtrfnbhvWevuPTvPCnublv3qqwldz7ZuJrtVa7HlxFghXxq9D+v6rFBvQ omfrm/QmBPSv6j9wKgwsvVZENrA3asOz91x3TCG5bqpAP9Wyh02RL4B1R4tv02fbgBCP /WF32CVj+Fp0fqbi641CqEPu1n0fMPhQOFgsU4AnOd4kORGxXusi4a/HnZidcpvIJyTH IMw2luFJ0i3dAkSIVT2JYQGe/UkBWR1N9gPT2pqSwh8vf+MEUO74CtqhND6Tms3LIzOu ss0D4k+XLzHv4hDDMalULYQ9Oy5NpNdGZpGv4jLu7DcKCc9mYeLnv//uJkdy7Tuw5b/+ lHsg== 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=s83rr/+F3LFoI5akAJvG7f+wHNh8/A2WtqrbA6ZYTdw5OTfUDqGRgwKXD+n5DWWXNC y98X2yniu7lNoCGP0CrZ1yshxOZFG+YzFW1GeKz1zWxcBa3osmcoUpFqxIKjs9GI3lBC 6JrgViDQJIqaNwcqFsTBdxPoYP2PQJOaRVfS0oUPNxZhpufYL7J/iCHkr+b3DXMvHTgv dN37sFMnzGHMZIhNEQKuYxFIAQ6isHGp6EWrMc7t7ogPCqbWehW8X07spl8Vy9mhpF1/ eYB8LquHLfFmiHLXaM8FjqOUIYOmHznIbI894JzbPXGWUajptnJweALhE/HmieoBgC/8 j5Pw== 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 t2si9052652ejf.408.2021.08.01.16.46.49; Sun, 01 Aug 2021 16:47:11 -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 S231819AbhHAXpg (ORCPT + 99 others); Sun, 1 Aug 2021 19:45:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36128 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231615AbhHAXpf (ORCPT ); Sun, 1 Aug 2021 19:45:35 -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 2E962C06175F for ; Sun, 1 Aug 2021 16:45:27 -0700 (PDT) Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: ezequiel) with ESMTPSA id 9AD2E1F424CC 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 20:45:04 -0300 Message-Id: <20210801234509.18774-3-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