From: Christoph Hellwig <hch@lst.de>
To: Daniel Golle <daniel@makrotopia.org>
Cc: Miquel Raynal <miquel.raynal@bootlin.com>,
linux-mtd@lists.infradead.org,
Vignesh Raghavendra <vigneshr@ti.com>,
Richard Weinberger <richard@nod.at>,
David Woodhouse <dwmw2@infradead.org>,
Christoph Hellwig <hch@lst.de>, Jan Kara <jack@suse.cz>,
Hannes Reinecke <hare@suse.de>
Subject: Re: [PATCH v4] mtd: super: don't rely on mtdblock device minor
Date: Tue, 11 May 2021 07:49:55 +0200 [thread overview]
Message-ID: <20210511054955.GA6542@lst.de> (raw)
In-Reply-To: <YJmx3Ru/5oyq6Y1a@makrotopia.org>
On Mon, May 10, 2021 at 11:21:17PM +0100, Daniel Golle wrote:
> For blktrans devices with partitions (ie. part_bits != 0) the
> assumption that the minor number of the mtdblock device matches
> the mtdnum doesn't hold true.
> Properly resolve mtd device from blktrans layer instead.
Why are you changing the legacy lookup method that is clearly deprecated
in favor of the mdt* syntax?
> +
> + if (MAJOR(bdev->bd_dev) == MTD_BLOCK_MAJOR) {
> + if (!bdev->bd_disk)
> + goto error_mtdblock;
bdev->bd_disk can't be NULL.
>
> + blktrans_dev = (struct mtd_blktrans_dev *)(bdev->bd_disk->private_data);
Overly long line due to the not actually required cast.
But more importantly you can't just look at the private data of a random
block device that you just opened. There is absolutely no guarantee that
it actually points to a specific private data.
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next prev parent reply other threads:[~2021-05-11 10:38 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-04-07 21:55 [PATCH] mtd: super: don't reply on mtdblock device minor Daniel Golle
2021-04-08 6:15 ` Miquel Raynal
2021-04-08 20:42 ` [PATCH v2] " Daniel Golle
2021-04-12 15:14 ` [PATCH v3] mtd: super: don't rely " Daniel Golle
2021-05-10 10:18 ` Miquel Raynal
2021-05-10 22:20 ` Daniel Golle
2021-05-10 22:21 ` [PATCH v4] " Daniel Golle
2021-05-11 5:49 ` Christoph Hellwig [this message]
2021-05-11 7:57 ` Daniel Golle
2021-05-11 16:42 ` Christoph Hellwig
2021-05-11 20:17 ` Daniel Golle
2021-05-12 6:42 ` Christoph Hellwig
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