In order to be able to identify what code is compiled into modules (even
built-in 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_cflahs), 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 soure files.
Signed-off-by: Kris Van Hees <kris.van.hees@oracle.com>
---
scripts/Makefile.lib | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 9f06f6aaf7fc..f4aec3553ff2 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)
--
2.45.1On Mon, 15 Jul 2024 23:10:42 -0400 Kris Van Hees <kris.van.hees@oracle.com> wrote: As mentioned before, should start off with the goal. 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, ... > In order to be able to identify what code is compiled into modules (even > built-in 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_cflahs), 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 soure files. The rest looks good. Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> -- Steve > > Signed-off-by: Kris Van Hees <kris.van.hees@oracle.com> > --- > scripts/Makefile.lib | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib > index 9f06f6aaf7fc..f4aec3553ff2 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)
On Wed, Aug 14, 2024 at 01:17:46PM -0400, Steven Rostedt wrote: > On Mon, 15 Jul 2024 23:10:42 -0400 > Kris Van Hees <kris.van.hees@oracle.com> wrote: > > > As mentioned before, should start off with the goal. > > 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, ... Ok, I see what you mean. Fixing that. Thanks! > In order to be able to identify what code is compiled into modules (even > > built-in 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_cflahs), 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 soure files. > > The rest looks good. > > Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Thanks! > > -- Steve > > > > > Signed-off-by: Kris Van Hees <kris.van.hees@oracle.com> > > --- > > scripts/Makefile.lib | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib > > index 9f06f6aaf7fc..f4aec3553ff2 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)
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