F9 (bug?) Superblock features different from backup

[Eric Sandeen]

Ahmed Kamal wrote:
> Just out of curiosity, could you let me know what kind of changes the
> kernel makes to the superblock without asking first! That sounds interesting

sure, things like the first time a "large" (> 2G file) is written it
will set a flag to that effect.

Or the first time an extent-based file is created on ext4.

We've talked about removing these, actually, and requiring the flags to
be set at mkfs time, or via tune2fs, if you wish to use the feature,
rather than silently turning them on.

-Eric