patch for ext2fs unmount problem at shutdown

Matthias Andree matthias.andree at
Tue Sep 6 02:01:36 PDT 2005

"Poul-Henning Kamp" <phk at> writes:

> PS: Considering power management, sleep/suspend modes etc, it would
> make sense to add a "MNT_CLEAN" flag to pass to VOP_FSYNC which
> instructed the filesystem to flush everything to disk, and reset
> any "dirty" flags on the disk to "clean" but leave the filesystem
> mounted.  (On subsequent I/O the first thing the filesystem must
> do is set the dirty flag again.  That way it would be as safe (as
> possible) to power a sleeping/suspend machine off.

If you have proper cache flushing/synchronization semantics (such as
putting an ATA disk to sleep), go right ahead - but woe betide the user
whose disk choses to reorder writes and sleep before flushing the whole

Matthias Andree

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