Ralf Baechle wrote: > On Sun, Mar 05, 2006 at 09:09:58AM +0100, Jan-Benedict Glaw wrote: > >> On Sun, 2006-03-05 14:17:56 +0800, zhuzhenhua <zzh.hust@xxxxxxxxx> wrote: >> > if in my product based ide disk, i want to it to support the >> > u-disk(with vfat fs), and can i set the root fs as vfat too? >> > if use vfat as rootfs, what's disadvantage of the selection? >> >> Well, most notably you won't have device nodes. Maybe a ram-backed >> filesystem mounted to /dev/ could solve that, but you'd probably need >> an initrd for that to do. > > It's anso case-insensitive which may cause some further troubles. It's > doesn't have proper inodes, no UNIX file modes, no UID / GID support (These > two can be kludges in awfully insufficient way through mount options), not > only lacks device special files but also no FIFO, no UNIX domain sockets, > no hard or soft links. It's simply a sorry excuse for a useful filesystem. It's attractive for a limited resource device that needs to have FAT support for a removable flash memory card (for Windows PC interoperability). If you can use FAT for the root fs, that reduces the system resource needs. It doesn't make sense if his ide disk is non-removable though. -Geoff