[PATCH] kbuild: build a single module using 'make dir/module.ko'

Using the syntax:
make dir/module.ko

kbuild now allows one to build a module including the final link stage.
This is usefull when one only wants to compile a single module and thus do
not have to wait until a full kernel has finished compiling.  Tested by:
randy_dunlap <rdunlap@xenotime.net>

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/Makefile b/Makefile
index 2717223d8666b1c2001427d6ffd2004bea8de488..9cf07e7b9f88dc43da8c06dde1b949f50b479aac 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -792,6 +792,9 @@ export CPPFLAGS_vmlinux.lds += -P -C -U$(ARCH)
        $(Q)$(MAKE) $(build)=$(@D) $@
 %.o: %.c scripts FORCE
        $(Q)$(MAKE) $(build)=$(@D) $@
+%.ko: scripts FORCE
+       $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) $(build)=$(@D) $(@:.ko=.o)
+       $(Q)$(MAKE) -rR -f $(srctree)/scripts/Makefile.modpost
 %/:      scripts prepare FORCE
        $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) $(build)=$(@D)
 %.lst: %.c scripts FORCE
@@ -1033,6 +1036,7 @@ help:
        @echo  '  modules_install - Install all modules'
        @echo  '  dir/            - Build all files in dir and below'
        @echo  '  dir/file.[ois]  - Build specified target only'
+       @echo  '  dir/file.ko     - Build module including final link'
        @echo  '  rpm             - Build a kernel as an RPM package'
        @echo  '  tags/TAGS       - Generate tags file for editors'
        @echo  '  cscope          - Generate cscope index'