[Unionfs] Re: timestamp/mtime related bugs, probable fix

[pascal at pabr.org]

This patch looks promising, thanks, I will be testing it too.

Erez Zadok wrote:
> +	 (upper inode time being the max of all lower ones).

By the way, I find this policy a little odd.

For regular files, it looks like if one lower branch has the
highest mtime and another branch has the highest ctime,
then the timestamps of the upper file will not match those
of any individual lower file (which would be disturbing).
Is that correct ?

Besides, in order to preserve the invariant, the implementation
seems to assume that lower timestamps can only increase over
time (which is not true).  Wouldn't it be safer to reset the
timestamps at the beginning of unionfs_copy_attr_times() too ?

Pascal