kern/47309: NetBSD 5.2 hangs at boot in a QEMU VM when ACPI is enabled.

[g1pi%libero.it@localhost]

>Number:         47309
>Category:       kern
>Synopsis:       NetBSD 5.2 hangs at boot in a QEMU VM when ACPI is enabled.
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue Dec 11 10:45:00 +0000 2012
>Originator:     g one
>Release:        5.2
>Organization:
>Environment:
NetBSD n5 5.2 NetBSD 5.2 (GENERIC) #0: Wed Nov 28 09:36:47 UTC 2012  
builds%b8.netbsd.org@localhost:/home/builds/ab/netbsd-5-2-RELEASE/i386/201211280503Z-obj/home/builds/ab/netbsd-5-2-RELEASE/src/sys/arch/i386/compile/GENERIC
 i386
>Description:
In a QEMU VM (host OS: linux 2.6.32 32-bit, host cpu Intel(R) Core(TM)2 Duo CPU 
P8600  @ 2.40GHz), NetBSD hangs at boot while scanning the IDE channel.

The only way to boot either the install CD or the installed HD system, is to 
disable ACPI.  Booting without any HD image works too, although this is of 
limited use.

NetBSD 5.1.2 worked correctly on the same platform, therefore it seems a 
regression.


>How-To-Repeat:
qemu -hda /tmp/n.qcow2 -monitor stdio -m 128
>Fix:
Pick one:
- Disable ACPI at boot
- Upgrade to NetBSD 6.0
- Downgrade to NetBSD 5.1.2