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    Subject[PATCH] ext3: Update Kconfig description of EXT3_DEFAULTS_TO_ORDERED
    From: Theodore Ts'o <>

    The old description for this configuration option was perhaps not
    completely balanced in terms of describing the tradeoffs of using a
    default of data=writeback vs. data=ordered. Despite the fact that old
    description very strongly recomended disabling this feature, all of
    the major distributions have elected to preserve the existing 'legacy'
    default, which is a strong hint that it perhaps wasn't telling the
    whole story.

    This revised description has been vetted by a number of ext3
    developers as being better at informing the user about the tradeoffs
    of enabling or disabling this configuration feature.

    Signed-off-by: "Theodore Ts'o" <>
    Signed-off-by: Jan Kara <>
    fs/ext3/Kconfig | 32 +++++++++++++++++---------------
    1 files changed, 17 insertions(+), 15 deletions(-)

    diff --git a/fs/ext3/Kconfig b/fs/ext3/Kconfig
    index fb3c1a2..522b154 100644
    --- a/fs/ext3/Kconfig
    +++ b/fs/ext3/Kconfig
    @@ -29,23 +29,25 @@ config EXT3_FS
    module will be called ext3.

    - bool "Default to 'data=ordered' in ext3 (legacy option)"
    + bool "Default to 'data=ordered' in ext3"
    depends on EXT3_FS
    - If a filesystem does not explicitly specify a data ordering
    - mode, and the journal capability allowed it, ext3 used to
    - historically default to 'data=ordered'.
    - That was a rather unfortunate choice, because it leads to all
    - kinds of latency problems, and the 'data=writeback' mode is more
    - appropriate these days.
    - You should probably always answer 'n' here, and if you really
    - want to use 'data=ordered' mode, set it in the filesystem itself
    - with 'tune2fs -o journal_data_ordered'.
    - But if you really want to enable the legacy default, you can do
    - so by answering 'y' to this question.
    + The journal mode options for ext3 have different tradeoffs
    + between when data is guaranteed to be on disk and
    + performance. The use of "data=writeback" can cause
    + unwritten data to appear in files after an system crash or
    + power failure, which can be a security issue. However,
    + "data=ordered" mode can also result in major performance
    + problems, including seconds-long delays before an fsync()
    + call returns. For details, see:
    + If you have been historically happy with ext3's performance,
    + data=ordered mode will be a safe choice and you should
    + answer 'y' here. If you understand the reliability and data
    + privacy issues of data=writeback and are willing to make
    + that trade off, answer 'n'.

    config EXT3_FS_XATTR
    bool "Ext3 extended attributes"

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