Tejun Heo <htejun@xxxxxxxxx> wrote: > This really isn't a regression. It's been always like that with libata. > libata doesn't make devices go into standby mode and shutdown(8) does > it for libata. The problem here is that libata does issue > SYNCHRONIZE_CACHE on shutdown. So, the sequence of event is... > > 1. shutdown(8) issues SYNCHRONIZE_CACHE followed by STANDBY_NOW > 2. kernel shutdown starts > 3. libata shutdown issues SYNCHRONIZE_CACHE > 4. power goes off > > Some drives seem to spin up at step #3 even when its cache is clean and > power goes off right after the disk finishes the command. So, it's > really bad when it happens - spin down, spin up followed by immediate > power off. > > SCSI part of the fix is queued in scsi-misc-2.6 tree and libata-dev part > is acked and waiting to be merged, so the fix will be available in > 2.6.22. However, it's disabled by default to remain compatible with the ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ > current behavior and requires userland change to fully fix the problem. ^^^^^^^^^^^^^^^^ It sounds like the Schilling kind of compatibility: "The old burner destroyed your disk on buffer underruns, therefore the new thing should do the same instead of giving you a perfectly readable data disk." Guys, not destroying hardware is _NOT_ bad! -- Anger, fear, aggression. The Dark Side of the Force are they. Once you start down the Dark Path, forever will it dominate your destiny. -- Jedi Master Yoda Friß, Spammer: QuG4KfL@xxxxxxxxxxxxxxxxxxxxxx - To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html