h2dioscan
h2dioscan(kd, 4, cp);
h2dioscan(kd, tab, (uintptr_t)dio.rbnode.rbe_left);
h2dioscan(kd, tab, (uintptr_t)dio.rbnode.rbe_right);
static void h2dioscan(kvm_t *kd, int tab, uintptr_t cp);