In order to create the file at build time, modules.builtin.ranges, that contains the range of addresses for all built-in modules, there needs to be a way to identify what code is compiled into modules.
To identify what code is compiled into modules during a kernel build, one can look for the presence of the -DKBUILD_MODFILE and -DKBUILD_MODNAME options in the compile command lines. A simple grep in .*.cmd files for those options is sufficient for this. Unfortunately, these options are only passed when compiling C source files. Various modules also include objects built from assembler source, and these options are not passed in that case. Adding $(modfile_flags) to modkern_aflags (similar to modkern_cflags), and adding $(modname_flags) to a_flags (similar to c_flags) makes it possible to identify which objects are compiled into modules for both C and assembler source files. While KBUILD_MODFILE is sufficient to generate the modules ranges data, KBUILD_MODNAME is passed as well for consistency with the C source code case. Signed-off-by: Kris Van Hees <kris.van.h...@oracle.com> Reviewed-by: Steven Rostedt (Google) <rost...@goodmis.org> Tested-by: Sam James <s...@gentoo.org> --- Notes: Changes since v8: - Fixed typos. - Explained KBUILD_MODNAME being added for consistency. scripts/Makefile.lib | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 207325eaf1d1..feea1c6c11db 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -238,7 +238,7 @@ modkern_rustflags = \ modkern_aflags = $(if $(part-of-module), \ $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE), \ - $(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL)) + $(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL) $(modfile_flags)) c_flags = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ -include $(srctree)/include/linux/compiler_types.h \ @@ -248,7 +248,7 @@ c_flags = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ rust_flags = $(_rust_flags) $(modkern_rustflags) @$(objtree)/include/generated/rustc_cfg a_flags = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ - $(_a_flags) $(modkern_aflags) + $(_a_flags) $(modkern_aflags) $(modname_flags) cpp_flags = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ $(_cpp_flags) -- 2.45.2