Generate mini.config:

- cd into kernel directory
- copy .config to dot-config
- invoke 
         miniconfig.sh dot-config
  - use appropriate path to miniconfig.sh and dot-config
  - this will take a while (up to an hour)
  - result is a file mini.config
- if there are different dot-config files (e.g. for up, smp, xen) 
  repeat the process for each of them
- find a common subset and save that to mini.config, the differences
  to mini.config{,-smp}.additions

Generate .config using mini.config and *.addtions

- cd into kernel directory

  cat mini.config mini.config.addtions >  template
  make allnoconfig KCONFIG_ALLCONFIG=template

Build Kernel

  ...

Files:
  miniconfig.sh
    - script used to generate mini.config
  mini.config-up, mini.config-smp 
    - files generated from up, smp dot-config
  mini.config 
    - common subset of mini.config-up, mini.config-smp
  mini.config.additions, mini.config-smp.additions,
    - additional config values for up, smp