vm_page_max_address
phys_addr_t vm_page_max_address();
if (newtag->lowaddr < vm_page_max_address())
phys_addr_t vm_page_max_address();
|| (uint64)vm_page_max_address() < (uint64)1 << 32) {
if (vm_page_max_address() >= (phys_addr_t)1 << 32) {