Automatically answer defaults when doing 'make oldconfig' on a kernel tree
is what you want. From the help (
make help in the kernel source dir)
olddefconfig - Same as silentoldconfig but sets new symbols to their default value
Use the command :
yes "" | make oldconfig
The 'yes' command repeatedly output a line with all specified string, or 'y' by default.
So, you can use it to simply "press enter", which will result in using the defaults value for the 'make oldconfig' command.