On Wed, Jan 10, 2024 at 06:59:25AM +0000, Meng, Li (Jassmine) wrote: > The reason why I added the selects is just to distinguish different > pstate drivers. These two drivers cannot be supported simultaneously > in the same project. No, that's not what I meant. Read here: "- reverse dependencies: "select" <symbol> ["if" <expr>] While normal dependencies reduce the upper limit of a symbol (see below), reverse dependencies can be used to force a lower limit of another symbol. The value of the current menu symbol is used as the minimal value <symbol> can be set to. If <symbol> is selected multiple times, the limit is set to the largest selection. Reverse dependencies can only be used with boolean or tristate symbols. Note: select should be used with care. select will force a symbol to a value without visiting the dependencies. By abusing select you are able to select a symbol FOO even if FOO depends on BAR that is not set. In general use select only for non-visible symbols (no prompts anywhere) and for symbols with no dependencies. That will limit the usefulness but on the other hand avoid the illegal configurations all over." >From Documentation/kbuild/kconfig-language.rst -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette