By default, the kernel contains a database of all known Zorro device names to make the information in /proc/iomem comprehensible to the user. This database increases the size of the kernel image by about 15KB, but it gets freed after the system boots up, so it doesn't take up kernel memory. Anyway, if you are building an installation floppy or kernel for an embedded system where kernel image size really matters, you can disable this feature and you'll get device ID numbers instead of names. When in doubt, say Y.