The kernel configuration is saved in the /usr/src/linux/.config file. It is highly recommended that you make a backup copy of this file, for example in the /root directory, so that you can not only reuse it later, but also save configurations for different kernels, as this is just a matter of giving different names to configuration files.
One possibility is to name configuration files after the kernel version. Say you modified your kernel version as shown Configuring The Kernel, then you can do:
$ cp .config /root/config-2.4.10-foo |
$ cp /root/config-2.4.10-foo .config |
However, apart from the chore of going through all the menus again, you can possibly miss some interesting new option(s). You can avoid this by using make oldconfig. It has two advantages:
it's fast;
if a new option appears in the kernel and wasn't present in your configuration file, it will stop and wait for you to enter your choice.
![]() | After you have copied your .config to the root home, as proposed above, run make mrproper. It will ensure nothing remains from the old configuration and you will get a clean kernel. |
Next, time for compilation.