I am trying to understand what the config option called CONFIG_SWAP_IO_SPACE means. It is used in io.h to swap upper and lower bytes depending on the endianness.I know it has got something to do with PCI I/O space. But I ain't very clear about it. Any help appreciated. Manoj -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ IRC Channel: irc.openprojects.net / #kernelnewbies Web Page: http://www.kernelnewbies.org/