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Date: Thu, 29 Oct 2026 13:12:20 +0100
From: Christoph Hellwig <hch@lst.de>
To: Christian Brauner <brauner@kernel.org>
Cc: linux-fsdevel@vger.kernel.org, Christoph Hellwig <hch@lst.de>,
	Chris Mason <clm@meta.com>, Josef Bacik <josef@toxicpanda.com>,
	Matthew Wilcox <willy@infradead.org>,
	Zhang Yi <yi.zhang@huaweicloud.com>,
	Joanne Koong <joannelkoong@gmail.com>,
	"Darrick J. Wong" <djwong@kernel.org>,
	Brian Foster <bfoster@redhat.com>, linux-xfs@vger.kernel.org,
	stable@vger.kernel.org
Subject: Re: [PATCH 1/2] iomap: don't mark unwritten parts of a folio
 uptodate
Message-ID: <20261029121220.GA24197@lst.de>
References: <20261029-work-iomap-ai-fixes-v1-0-7eda63bc1b13@kernel.org> <20261029-work-iomap-ai-fixes-v1-1-7eda63bc1b13@kernel.org>
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User-Agent: Mutt/1.5.17 (2007-11-01)

On Thu, Oct 29, 2026 at 11:34:48AM +0100, Christian Brauner wrote:
> on disk. A source buffer that ends in an unmapped page is enough:
> 
>         ftruncate(fd, 4096);
>         pwrite(fd, p, 3000, 100);    /* 16 bytes at p, then PROT_NONE */
>         pread(fd, buf, 4096, 0);

Can we wire this up to xfstests, please?

> Willy reported this back in 2024 (cf. [1]) and Zhang Yi posted the same
> fix (cf. [2]) but it never got merged.

Should we credit the original submission then?