mtime of untouched files changed?

[Josh Boyer]

On Tue, May 19, 2015 at 11:46 AM, Reindl Harald <h.reindl at thelounge.net> wrote:
>>> commit 8f4d855839179f410fa910a26eb81d646d628f26
>>> Author: Theodore Ts'o <tytso at mit.edu>
>>> Date:   Thu May 14 18:19:01 2015 -0400
>>>
>>>      ext4: fix lazytime optimization
>>>
>>>      We had a fencepost error in the lazytime optimization which means
>>> that
>>>      timestamp would get written to the wrong inode.
>>>
>>>      Cc: stable at vger.kernel.org
>>>      Signed-off-by: Theodore Ts'o <tytso at mit.edu>
>>
>>
>> which looks like it's probably the culprit.  This was broken since:
>>
>>> commit a26f49926da938f47561f386be56a83dd37a496d
>>> Author: Theodore Ts'o <tytso at mit.edu>
>>> Date:   Mon Feb 2 00:37:02 2015 -0500
>>>
>>>      ext4: add optimization for the lazytime mount option
>
>
> wow - and nobody noticed all the months that mtimes are randomly changing
> all over the system while it takes exactly one day to get rkhunter mails and
> rsync listing a ton of untouched files

That isn't really all that surprising.  The lazytime mount option is
very new, isn't used by default anywhere, and likely isn't widely
tested outside of the usecase the original developers had in mind.

josh