On Tue, Jul 15, 2008 at 12:03:27PM +0200, Andi Kleen wrote: > Matthew Wilcox <matthew@xxxxxx> writes: > > > > I don't understand why we want to know about these CPUs. Surely they > > should be 'possible', but not 'present'? What useful thing can Linux do > > with them? > > He explained it in the intro, near the end (I nearly complained about > this too when I hadn't finished reading it completely :): > > |The big picture implication is that we can allow userspace > |to interact with disabled CPUs. In this particular example, > |we provide a knob that lets a sysadmin schedule any present > |CPU for firmware deconfiguration or enablement. > > The reason sounds pretty exotic, but ok. I don't see why this needs to be cross architecture then - shouldn't the generic kernel only be concerning itself with things that are possible, present and/or online? If you have an interface which allows you to change the machines configuration in a machine specific way, shouldn't that be something for that machine to support and forced upon the entire kernel? -- Russell King Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/ maintainer of: -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
