efi_call_virt_pointer
ret = efi_call_virt_pointer(tab, function, (u64)which, a1, a2, a3, a4, a5);
status = efi_call_virt_pointer(efi.runtime, set_variable, name, vendor,
status = efi_call_virt_pointer(efi.runtime, query_variable_info, attr,