xc_priority
xc_priority(arg1, arg2, (xc_arg_t)&rc,
xc_priority((xc_arg_t)&newkernel, 0, 0, CPUSET2BV(cpuset),
xc_priority(0, 0, 0, CPUSET2BV(xcset), mach_cpu_halt);
xc_priority(0, 0, 0, CPUSET2BV(xcset), (xc_func_t)panic_idle);
extern void xc_priority(xc_arg_t, xc_arg_t, xc_arg_t, ulong_t *, xc_func_t);