Excuse me, It's a little offtopic.
I was talking about implement SMP via hardware in Hurd (Mach really). In this implementation, Mach configures the processor during the boot, enabling multicore support. (All Pentium 4 or modern x86 processor supports this)
In the current SMP support, this multicore support feels been build from software, generating the threads and assigning It to the processor from software. Then, my idea is to start a project to change this SMP software to a newer implementation via hardware, as I previously said. As this form, we don't need to know how many cores has the processor and set the core number in Mach in compilation time. Instead, the same processor will detect the cores number and configure SMP automatically.
This can be an interesting project, and could to be a good improvement to the Hurd.