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Date:   Thu, 29 Sep 2022 21:45:04 -0600 (Mountain Daylight Time)
From:   =?UTF-8?Q?Marc_Aur=C3=A8le_La_France?= <tsi@tuyoix.net>
To:     "Theodore Ts'o" <tytso@mit.edu>
cc:     Andreas Dilger <adilger.kernel@dilger.ca>,
        linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] ext4: Register ext[23] support only after successful
 ext4 registration
In-Reply-To: <YzWpv8ZKJ7BrOBsg@mit.edu>
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References: <7ef87cdb-0d0b-2488-6f42-a670a6454630@tuyoix.net> <YzWpv8ZKJ7BrOBsg@mit.edu>
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On Thu, 29 Sep 2022, Theodore Ts'o wrote:
> On Wed, Aug 10, 2022 at 02:20:45PM -0600, Marc Aurèle La France wrote:
>> Register ext4 as a "replacement" for ext2 and ext3 only after ext4 itself has
>> been successfully registered.  As a side effect, this allows
>> unregister_as_ext[23]() to be inlined.

> The corrent ordering is deliberate; it allows file systems that have
> ext2 and ext3 only file system features will be reported as using ext2
> and ext3 in /proc/mounts.  This doesn't matter quite as much, but it
> could potentially break userspace if a legacy file system that only
> has ext2 file system features is mounted and reported as ext4.

> So sorry, I can't take this change.

Fair enough.  Thanks for responding.

Marc.
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