kern/117918: HP dc5750 will only boot with ACPI disabled

[Pete French]

>Number:         117918
>Category:       kern
>Synopsis:       HP dc5750 will only boot with ACPI disabled
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Thu Nov 08 13:00:09 UTC 2007
>Closed-Date:
>Last-Modified:
>Originator:     Pete French
>Release:        FreeBSD 6.3-PRERELEASE i386
>Organization:
Ticket Switch Ltd
>Environment:
System: FreeBSD dilbert.rattatosk 6.3-PRERELEASE FreeBSD 6.3-PRERELEASE #0: Tue Nov 6 20:42:48 GMT 2007 petefrench at dilbert.rattatosk:/mnt/fast/usr.obj/usr/src/sys/GENERIC i386


>Description:

	This workstation - an HP dc5750 panics if you try and boot with ACPI
	enabled. I realise that there is another problem with these machines
	relating to the SMAP as reported in 111952, but this appears to
	be different. I see the SMAP probelem if I boot in amd64 (with or
	without ACPI enabled) but under i386 it simply panics before even
	getting to that stage.

	I am using the latest BIOS from HP, and a version of -STABLE
	from two days ago (November 6th).


>How-To-Repeat:

	Attempt to boot a 6.3 kernel on one of these machines with ACPI
	enabled.
	
>Fix:

	Disabling ACPI enables the machine to boot - but it then requires
	the amount of physical memory to be set by hand in loader.conf 
	and cannot see the 2nd processor.
>Release-Note:
>Audit-Trail:
>Unformatted: