drity and then setting the s_dirt flag. And when 'write_super()' is executed to
handle the s_dirt flag, we just update the timestamp and again mark the
superblock buffer as dirty. Seems pointless.

It's the way sysv itself does stuff. The timestamp on v7/sys3/sys5
reflects the clock on the box. A lot of ancient boxes with no decent
hardware clocks used to reset the system time off the root fs superblock
on a loss of power.

Alan