kern/121558: Supermicro X7SB4 Fatal trap 12 when ACPI disabled

[Leon Kos]

mptable output of the system is located at:
http://www.lecad.uni-lj.si/~leon/other/x7sb4/mptable.txt

I could not change version in BIOS. Processor option supported by BIOS are
shown in http://www.lecad.uni-lj.si/~leon/other/x7sb4/img_1638.jpg

I have added
options     INVARIANTS
options     INVARIANT_SUPPORT
options     DIAGNOSTIC

and now GENERIC shows the following trace when ACPI disabled:
http://www.lecad.uni-lj.si/~leon/other/x7sb4/img_1639.jpg
http://www.lecad.uni-lj.si/~leon/other/x7sb4/img_1640.jpg
http://www.lecad.uni-lj.si/~leon/other/x7sb4/img_1641.jpg


Forcing single core in BIOS helps when running ACPI disabled.
Toggling other BIOS options like C1 Enhanced Mode or Speed Step
does not.


Kind regards!

Leon Kos, CAD lab, Mech.Eng., University of Ljubljana, Slovenia
(http://www.lecad.uni-lj.si/~leon)