Kernel Support in Linux PPC

Hi

I am developing a Linux Kernel Module which basically would do native
bridging with VLAN and RSTP. The LKM basically would make use of
sk_buff ,net_device, timers, locks etc. I am developing this in i386
platform and the kernel version is 2.6.15.4 and it works fine as of
now. Now i need to move from i386 to PPC architecture with the same
version of the kernel and then move from 2.6.15.4 to 2.6.26 in the PPC
architecture.

I would like to know whether would i face any big surprises/changes
apart from the sk_buff and netdevice data structure changes in the
latest versions of the kernel ?

Thanks for your help

Cheers,
Balaji