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Date: Mon, 12 Aug 2024 15:25:27 +0200
From: Christoph Hellwig <hch@lst.de>
To: Miquel Raynal <miquel.raynal@bootlin.com>
Cc: Christian Marangi <ansuelsmth@gmail.com>,
	Ulf Hansson <ulf.hansson@linaro.org>, Rob Herring <robh@kernel.org>,
	Krzysztof Kozlowski <krzk+dt@kernel.org>,
	Conor Dooley <conor+dt@kernel.org>,
	Richard Weinberger <richard@nod.at>,
	Vignesh Raghavendra <vigneshr@ti.com>,
	Joern Engel <joern@lazybastard.org>,
	Keith Busch <kbusch@kernel.org>, Jens Axboe <axboe@kernel.dk>,
	Christoph Hellwig <hch@lst.de>, Sagi Grimberg <sagi@grimberg.me>,
	Saravana Kannan <saravanak@google.com>,
	Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
	Wolfram Sang <wsa+renesas@sang-engineering.com>,
	Florian Fainelli <f.fainelli@gmail.com>, linux-mmc@vger.kernel.org,
	devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-mtd@lists.infradead.org, linux-nvme@lists.infradead.org
Subject: Re: [PATCH v4 0/7] mtd: improve block2mtd + airoha parser
Message-ID: <20240812132527.GB23655@lst.de>
References: <20240809172106.25892-1-ansuelsmth@gmail.com> <20240812104954.1e8d55f7@xps-13> <66b9df7c.050a0220.3574aa.d5bb@mx.google.com> <20240812151755.0feab4b2@xps-13>
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On Mon, Aug 12, 2024 at 03:17:55PM +0200, Miquel Raynal wrote:
> Is this supported in mainline Linux? MTD handles the bad blocks and the
> bad block tables, so I don't understand how this hardware feature can
> live together with MTD.
> 
> Anyway, you are talking about MMCs, I don't understand why there are
> bad blocks, nor what is checking them and when. This is all still very
> fuzzy to me, I'm sorry.

Yes.  The idea of using block2mtd for anything but development seems
a bit odd to say it politely.  Using it to reinvent bad block management
on top of a block device that needs to do that as one of it's fundamental
functions seems extremely odd.