SMP on x86/Linux is now an official feature and is not experimental. Experimental SMP support for other architectures is underway. Please view linux/Documentation/smp for more information about enabling SMP. SMP support for Linux with up to 16 processors using the Intel MP specification. To fix: o Clean up processor specific/independent split. o Document it all. [PARTLY DONE] o Halting other CPUs on reset or panic doesn't always work. o Don't waste page at 4 K--don't need it now (watch the GDT code). o Dump bootup pages once booted somehow. o Clean up warnings/volatiles. o 486 startup code. o How to handle mixed FPU/non FPU processors. o Test IO-APIC on various hardware. o Separate IO-APIC from SMP.