If you have not already done so, please do the following. Open YaST (Enter root user password) / Software / Software Management - Select the View Button on the top left and pick Patterns. Now, you will see several Patterns listed and you want to select:
Originally Posted by dmbgo
Then Press the Accept button on the bottom right and allow these applications to install. I suggest this because it appears you have not installed the kernel source code before.
[X] Base Development
[X] Linux Kernel Development
[X] C/C++ Development