RELENG_8 -- shutdown -p no longer powers off boxes

[Jeremy Chadwick]

Looks like some form of regression in RELENG_8, between the dates of
2010/03/30 and 2010/04/22.  My 2010/03/30 kernel (built from RELENG_8
source dated 2010/03/30 @ 10:30 PDT) doesn't have this problem.

Symptom: shutdown -p no longer powers off either of my systems; instead,
the box reboots (e.g. shutdown -p behaves like shutdown -r).  Systems
are a Supermicro X7SBL-LN2 board, and a Supermicro X7SBA board.  These
are server-class boards.  I have not tried using the physical power
switch yet.

Looks like others have reported the same on a different board, though I
haven't booted verbose to see if the behaviour is identical:

http://lists.freebsd.org/pipermail/freebsd-acpi/2010-March/006345.html
http://lists.freebsd.org/pipermail/freebsd-acpi/2010-April/006462.html

I went digging through HEAD commits between the above dates and wasn't
able to find much other than this, which appears to be the HEAD commit
that was MFC'd to RELENG_8:

http://freshbsd.org/2010/04/02/23/04/31

So I'm not sure where/what fixed this in HEAD, but it should probably be
MFC'd sooner than the 4 week window.

-- 
| Jeremy Chadwick                                   jdc at parodius.com |
| Parodius Networking                       http://www.parodius.com/ |
| UNIX Systems Administrator                  Mountain View, CA, USA |
| Making life hard for others since 1977.              PGP: 4BD6C0CB |