On Mon, Sep 11, 2017 at 11:05:23PM -0600, Ross Zwisler wrote:
The current code has the potential for data corruption when changing
an
inode's journaling mode, as that can result in a subsequent unsafe change
in S_DAX.
I've captured an instance of this data corruption in the following fstest:
https://patchwork.kernel.org/patch/9948377/
Prevent this data corruption from happening by disallowing changes to the
journaling mode if the '-o dax' mount option was used. This means that for
a given filesystem we could have a mix of inodes using either DAX or
data journaling, but whatever state the inodes are in will be held for the
duration of the mount.
Signed-off-by: Ross Zwisler <ross.zwisler(a)linux.intel.com>
Suggested-by: Jan Kara <jack(a)suse.cz>
Thanks, applied.
- Ted