diff options
Diffstat (limited to 'Documentation/kbuild')
| -rw-r--r-- | Documentation/kbuild/kconfig-language.txt | 17 | ||||
| -rw-r--r-- | Documentation/kbuild/modules.txt | 9 |
2 files changed, 17 insertions, 9 deletions
diff --git a/Documentation/kbuild/kconfig-language.txt b/Documentation/kbuild/kconfig-language.txt index 649cb87..00b950d 100644 --- a/Documentation/kbuild/kconfig-language.txt +++ b/Documentation/kbuild/kconfig-language.txt @@ -104,14 +104,15 @@ applicable everywhere (see syntax). Reverse dependencies can only be used with boolean or tristate symbols. Note: - select is evil.... select will by brute force set a symbol - equal to 'y' without visiting the dependencies. So 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. kconfig - should one day warn about such things. + 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. + kconfig should one day warn about such things. - numerical ranges: "range" <symbol> <symbol> ["if" <expr>] This allows to limit the range of possible input values for int diff --git a/Documentation/kbuild/modules.txt b/Documentation/kbuild/modules.txt index 1d247d5..1821c07 100644 --- a/Documentation/kbuild/modules.txt +++ b/Documentation/kbuild/modules.txt @@ -486,7 +486,7 @@ Module.symvers contains a list of all exported symbols from a kernel build. Sometimes, an external module uses exported symbols from another external module. Kbuild needs to have full knowledge on all symbols to avoid spitting out warnings about undefined symbols. - Two solutions exist to let kbuild know all symbols of more than + Three solutions exist to let kbuild know all symbols of more than one external module. The method with a top-level kbuild file is recommended but may be impractical in certain situations. @@ -523,6 +523,13 @@ Module.symvers contains a list of all exported symbols from a kernel build. containing the sum of all symbols defined and not part of the kernel. + Use make variable KBUILD_EXTRA_SYMBOLS in the Makefile + If it is impractical to copy Module.symvers from another + module, you can assign a space separated list of files to + KBUILD_EXTRA_SYMBOLS in your Makfile. These files will be + loaded by modpost during the initialisation of its symbol + tables. + === 8. Tips & Tricks --- 8.1 Testing for CONFIG_FOO_BAR |