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Date:   Tue, 14 Jan 2020 08:39:45 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     Ritesh Harjani <riteshh@linux.ibm.com>
Cc:     linux-ext4@vger.kernel.org, tytso@mit.edu, jack@suse.cz
Subject: Re: [RFC 0/2] ext4: Fix stale data read exposure problem with DIO
 read/page_mkwrite
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> Currently there is a small race window as pointed out by Jan [2] where, when
> ext4 tries to allocate a written block for mapped files and if DIO read is in
> progress, then this may result into stale data read exposure problem.

Do we have a test case for the problem?