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Date:   Mon, 9 Jan 2023 18:37:59 -0800
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Eric Biggers <ebiggers@kernel.org>
Cc:     linux-fscrypt@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-ext4@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net,
        linux-btrfs@vger.kernel.org, linux-xfs@vger.kernel.org,
        Andrey Albershteyn <aalbersh@redhat.com>
Subject: Re: [PATCH v2 10/11] fs/buffer.c: support fsverity in
 block_read_full_folio()
Message-Id: <20230109183759.c1e469f5f2181e9988f10131@linux-foundation.org>
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On Fri, 23 Dec 2022 12:36:37 -0800 Eric Biggers <ebiggers@kernel.org> wrote:

> After each filesystem block (as represented by a buffer_head) has been
> read from disk by block_read_full_folio(), verify it if needed.  The
> verification is done on the fsverity_read_workqueue.  Also allow reads
> of verity metadata past i_size, as required by ext4.

Sigh.  Do we reeeeealy need to mess with buffer.c in this fashion?  Did
any other subsystems feel a need to do this?

> This is needed to support fsverity on ext4 filesystems where the
> filesystem block size is less than the page size.

Does any real person actually do this?