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Date: Tue, 4 Aug 2026 16:01:02 +0200
From: Christoph Hellwig <hch@lst.de>
To: Tal Zussman <tz2294@columbia.edu>
Cc: Jens Axboe <axboe@kernel.dk>,
	Johannes Thumshirn <johannes.thumshirn@wdc.com>,
	Luis Chamberlain <mcgrof@kernel.org>,
	"Darrick J. Wong" <djwong@kernel.org>,
	Christoph Hellwig <hch@lst.de>, linux-block@vger.kernel.org,
	linux-kernel@vger.kernel.org, Sashiko <sashiko-bot@kernel.org>
Subject: Re: [PATCH 1/2] block: use iomap_dirty_folio for block devices
Message-ID: <20260804140102.GA8894@lst.de>
References: <20260802-blkdev-fixes-v1-0-a82fc549fd74@columbia.edu> <20260802-blkdev-fixes-v1-1-a82fc549fd74@columbia.edu>
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User-Agent: Mutt/1.5.17 (2007-11-01)

On Sun, Aug 02, 2026 at 07:14:26AM -0400, Tal Zussman wrote:
> To reproduce, on a device with a sub-page block size, write a known
> pattern with O_DIRECT, mmap the same range, store to it, msync() and
> fsync(), then read it back with O_DIRECT. A reproducer is available at

Heh, shared mmap writes to block devices..

> [1].
> 
> [1] https://gist.github.com/tzussman/18ab05cba4b3fdc79cce0a69d1fd05b4

Can you submit this to blktests?

Looks good:

Reviewed-by: Christoph Hellwig <hch@lst.de>