[Linux-kernel-mentees] [PATCH RFC] kbuild: use interpreters to invoke scripts
lukas.bulwahn at gmail.com
Thu Oct 1 14:09:54 UTC 2020
On Thu, 1 Oct 2020, Ujjwal Kumar wrote:
> On 01/10/20 4:38 pm, Lukas Bulwahn wrote:
> > On Thu, 1 Oct 2020, Ujjwal Kumar wrote:
> >> We cannot rely on execute bits to be set on files in the repository.
> >> The build script should use the explicit interpreter when invoking any
> >> script from the repository.
> >> Link: https://firstname.lastname@example.org/
> >> Link: https://lore.kernel.org/lkml/202008271102.FEB906C88@keescook/
> >> Suggested-by: Andrew Morton <akpm at linux-foundation.org>
> >> Suggested-by: Kees Cook <keescook at chromium.org>
> >> Suggested-by: Lukas Bulwahn <lukas.bulwahn at gmail.com>
> >> Signed-off-by: Ujjwal Kumar <ujjwalkumar0501 at gmail.com>
> >> ---
> >> Documentation/Makefile | 16 ++++++++--------
> >> Documentation/userspace-api/media/Makefile | 6 +++---
> >> Makefile | 4 ++--
> >> arch/arm64/kernel/vdso/Makefile | 2 +-
> >> arch/arm64/kernel/vdso32/Makefile | 2 +-
> >> arch/ia64/Makefile | 4 ++--
> >> arch/nds32/kernel/vdso/Makefile | 2 +-
> >> .../comedi/drivers/ni_routing/tools/Makefile | 6 +++---
> >> scripts/Makefile.build | 2 +-
> >> scripts/Makefile.package | 4 ++--
> >> tools/bootconfig/Makefile | 2 +-
> >> tools/bpf/Makefile.helpers | 2 +-
> >> tools/lib/bpf/Makefile | 2 +-
> >> tools/perf/Makefile.perf | 2 +-
> >> tools/power/cpupower/Makefile | 2 +-
> >> tools/testing/selftests/rcutorture/Makefile | 2 +-
> >> tools/testing/selftests/rseq/Makefile | 2 +-
> >> tools/testing/selftests/vm/Makefile | 6 +++---
> >> tools/testing/selftests/wireguard/qemu/Makefile | 4 ++--
> >> tools/testing/selftests/x86/Makefile | 6 +++---
> >> 20 files changed, 39 insertions(+), 39 deletions(-)
> > You will probably need to split this patch into multiple patches, but the
> > discussion will show how to split it best.
> > Probably:
> > - one for Documentation
> > - one for general kbuild, maybe including arch
> > - one for selftests
> > - one for the other tools
> > - one for the comedi driver
> > So, what did you do for testing your change?
> First, I had to unset the execute bits on all files.
> for i in $(find -executable -type f); do chmod -x $i; done
> To test the changes, I invoked the make rule under which my current
> changes lie. And I could see a permission-denied whenever a script
> was invoked. After the patch, the make rule progressed without
> any permissions error.
> I couldn't test each and every change, because some rules failed
> before invoking the script and others could not be invoked by me.
Which could you not test? Please share that.
> I successfully tested the changes under Documentation/ (and some others).
> $ make htmldocs
> make: execvp: ./scripts/sphinx-pre-install: Permission denied
> make: *** [Documentation/Makefile:81: htmldocs] Error 127
> make: *** [Makefile:1661: htmldocs] Error 2
> Files that I tested my changes on:
> Documentation/Makefile | 16 ++++++++--------
> Documentation/userspace-api/media/Makefile | 6 +++---
> Makefile | 4 ++--
> tools/perf/Makefile.perf | 2 +-
> tools/power/cpupower/Makefile | 2 +-
> > Did you check if CONFIG_SHELL is actually available in tools?
> Yes, I did check.
> To verify, I echo(ed) the variables under a make task. And invoked
> the task from srctree.
That sounds good.
> >> --- a/arch/nds32/kernel/vdso/Makefile
> >> +++ b/arch/nds32/kernel/vdso/Makefile
> >> @@ -39,7 +39,7 @@ $(obj)/%.so: $(obj)/%.so.dbg FORCE
> >> # Generate VDSO offsets using helper script
> >> gen-vdsosym := $(srctree)/$(src)/gen_vdso_offsets.sh
> >> quiet_cmd_vdsosym = VDSOSYM $@
> >> - cmd_vdsosym = $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@
> >> + cmd_vdsosym = $(NM) $< | $(CONFIG_SHELL) $(gen-vdsosym) | LC_ALL=C sort > $@
> > I guess it is better to modify gen-vdsosym.
> Do you mean something as follows:
> gen-vdsosym := $(CONFIG_SHELL) $(srctree)/$(src)/gen_vdso_offsets.sh
> If so, I have never seen that style in the build files. Infact, the current
> style is followed at many places.
> For instance,
I searched around as well. I think your proposal is fine.
How about splitting out a first patch on the generic kbuild files and send
that out as RFC, first send the RFC patch to linux-kernel-mentees list,
then if that looks good, we go for Masahiro and the linux-kbuild list?
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