No SMP without ACPI?

John Baldwin jhb at
Tue Oct 12 11:09:02 PDT 2004

On Saturday 09 October 2004 05:10 pm, John Wilson wrote:
> Hello all.
> I just recently installed -BETA7 on an Intel D865PERL mainboard.  After a
> quick cvsup of the src's, and a recompile of the kernel, it appears that
> SMP fails and falls back to UP even with HTT enabled in the BIOS, as well
> as the proper kernel options of:
> options         SMP             # Symmetric MultiProcessor Kernel
> device          apic            # I/O APIC
> I am unable to figure out why this is the case.  HTT does indeed function
> with ACPI enabled, but tends to panic the box on shutdown, thus the reason
> for attempting to do this with ACPI disabled.  Here is the dmesg:

This is normal.  MP Tables normally do not enumerate logical CPUs, where as 
the MADT table from ACPI does.  You can force the kernel to guess at the 
existence of logical CPUs in the non-ACPI case by using the 
'MPTABLE_FORCE_HTT' option in your kernel.

John Baldwin <jhb at>  <><
"Power Users Use the Power to Serve"  =

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