smp.h:
struct secondary_data {
	void* stack;
	struct task_struct* task;
	long status;
};

mpboot.c:
struct secondary_data secondary_data;

arch_boot_cpu() {
	struct task_struct* new_task = kmalloc(...);
	...
	secondary_data.task = new_task;
`	__flush_dcache_area(&secondary_data, sizeof(secondary_data));
	// WHAT SHOULD GO HERE??? HMM??
}