On Mon, Mar 30, 2015 at 10:58:12PM +0800, Woody Wu wrote:

Unfortunately I failed in 'modprobe'.

FFC3 3.1.0-ffc3mb-00050-g5874787 # pwd
/lib/modules/3.1.0-ffc3mb-00050-g5874787
FFC3 3.1.0-ffc3mb-00050-g5874787 # modprobe tun
modprobe: can't load module tun (net/tun.ko): invalid module format

FFC3 3.1.0-ffc3mb-00050-g5874787 # modinfo net/tun.ko
filename:       net/tun.ko
license:        GPL
author:         (C) 1999-2004 Max Krasnyansky [off-list ref]
description:    Universal TUN/TAP device driver
alias:          devname:net/tun
depends:
vermagic:       3.1.0-ffc3mb-00050-g5874787
-ffc3mb-00055-g4c6394f-dirty mod_unload ARMv5

Can you help to give a clue?  Thanks in advance!

Please work with the vendor that is forcing you to use such an old and
obsolete kernel version, they are the only ones that can help you out
here.

Also look in your kernel log, it will show errors when loading modules
as to what went wrong.

good luck,

greg k-h