Bugzilla Bug 189636

Since upgrading to 2.6.21 I get this message on shutdown.
I know that actually the disks are spun down but the message is annoying.
This apparently only happens with SATA drives.Boxes with IDE disks don't
show this message.

Reproducible: Always

Steps to Reproduce:
1.Shutdown.
2.
3.

Actual Results:  
The above message appears.

Expected Results:  
No disturbing message.

I came across this in /usr/src/linux/Documentation/feature-removal-schedule.txt

What: libata spindown skipping and warning
When: Dec 2008
Why:  Some halt(8) implementations synchronize caches for and spin
      down libata disks because libata didn't use to spin down disk on
      system halt (only synchronized caches).
      Spin down on system halt is now implemented.  sysfs node
      /sys/class/scsi_disk/h:c:i:l/manage_start_stop is present if
      spin down support is available.
      Because issuing spin down command to an already spun down disk
      makes some disks spin up just to spin down again, libata tracks
      device spindown status to skip the extra spindown command and
      warn about it.
      This is to give userspace tools the time to get updated and will
      be removed after userspace is reasonably updated.
Who:  Tejun Heo <htejun@gmail.com>

This has absolutely nothing to do with Gentoo Bugzilla product; read the
descriptions when filing bugs please.

*** This bug has been marked as a duplicate of bug 174373 ***