/* check for extension rom (ignore length byte!) */
rom = isa_bus_to_virt(extension_rom_resource.start);
if (romsignature(rom)) {
- length = extension_rom_resource.end - extension_rom_resource.start + 1;
+ length = resource_size(&extension_rom_resource);
if (romchecksum(rom, length)) {
request_resource(&iomem_resource, &extension_rom_resource);
upper = extension_rom_resource.start;