[Linux-kernel-mentees] [PATCH RFC] doc: kbuild: use interpreters to invoke scripts

[Ujjwal Kumar]

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://lore.kernel.org/lkml/20200830174409.c24c3f67addcce0cea9a9d4c@linux-foundation.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 +++---
  2 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/Documentation/Makefile b/Documentation/Makefile
index 6b12dd82f712..e74315074336 100644
--- a/Documentation/Makefile
+++ b/Documentation/Makefile
@@ -7,7 +7,7 @@ subdir- := devicetree/bindings
 
 # Check for broken documentation file references
 ifeq ($(CONFIG_WARN_MISSING_DOCUMENTS),y)
-$(shell $(srctree)/scripts/documentation-file-ref-check --warn)
+$($(PERL) $(srctree)/scripts/documentation-file-ref-check --warn)
 endif
 
 # You can set these variables from the command line.
@@ -29,7 +29,7 @@ ifeq ($(HAVE_SPHINX),0)
 .DEFAULT:
 	$(warning The '$(SPHINXBUILD)' command was not found. Make sure you have Sphinx installed and in PATH, or set the SPHINXBUILD make variable to point to the full path of the '$(SPHINXBUILD)' executable.)
 	@echo
-	@$(srctree)/scripts/sphinx-pre-install
+	@$(PERL) $(srctree)/scripts/sphinx-pre-install
 	@echo "  SKIP    Sphinx $@ target."
 
 else # HAVE_SPHINX
@@ -78,14 +78,14 @@ quiet_cmd_sphinx = SPHINX  $@ --> file://$(abspath $(BUILDDIR)/$3/$4)
 	$(abspath $(BUILDDIR)/$3/$4)
 
 htmldocs:
-	@$(srctree)/scripts/sphinx-pre-install --version-check
+	@$(PERL) $(srctree)/scripts/sphinx-pre-install --version-check
 	@+$(foreach var,$(SPHINXDIRS),$(call loop_cmd,sphinx,html,$(var),,$(var)))
 
 linkcheckdocs:
 	@$(foreach var,$(SPHINXDIRS),$(call loop_cmd,sphinx,linkcheck,$(var),,$(var)))
 
 latexdocs:
-	@$(srctree)/scripts/sphinx-pre-install --version-check
+	@$(PERL) $(srctree)/scripts/sphinx-pre-install --version-check
 	@+$(foreach var,$(SPHINXDIRS),$(call loop_cmd,sphinx,latex,$(var),latex,$(var)))
 
 ifeq ($(HAVE_PDFLATEX),0)
@@ -97,7 +97,7 @@ pdfdocs:
 else # HAVE_PDFLATEX
 
 pdfdocs: latexdocs
-	@$(srctree)/scripts/sphinx-pre-install --version-check
+	@$(PERL) $(srctree)/scripts/sphinx-pre-install --version-check
 	$(foreach var,$(SPHINXDIRS), \
 	   $(MAKE) PDFLATEX="$(PDFLATEX)" LATEXOPTS="$(LATEXOPTS)" -C $(BUILDDIR)/$(var)/latex || exit; \
 	   mkdir -p $(BUILDDIR)/$(var)/pdf; \
@@ -107,11 +107,11 @@ pdfdocs: latexdocs
 endif # HAVE_PDFLATEX
 
 epubdocs:
-	@$(srctree)/scripts/sphinx-pre-install --version-check
+	@$(PERL) $(srctree)/scripts/sphinx-pre-install --version-check
 	@+$(foreach var,$(SPHINXDIRS),$(call loop_cmd,sphinx,epub,$(var),epub,$(var)))
 
 xmldocs:
-	@$(srctree)/scripts/sphinx-pre-install --version-check
+	@$(PERL) $(srctree)/scripts/sphinx-pre-install --version-check
 	@+$(foreach var,$(SPHINXDIRS),$(call loop_cmd,sphinx,xml,$(var),xml,$(var)))
 
 endif # HAVE_SPHINX
@@ -120,7 +120,7 @@ endif # HAVE_SPHINX
 # work or silently pass without Sphinx.
 
 refcheckdocs:
-	$(Q)cd $(srctree);scripts/documentation-file-ref-check
+	$(Q)cd $(srctree);$(PERL) scripts/documentation-file-ref-check
 
 cleandocs:
 	$(Q)rm -rf $(BUILDDIR)
diff --git a/Documentation/userspace-api/media/Makefile b/Documentation/userspace-api/media/Makefile
index 81a4a1a53bce..5919b3e749fe 100644
--- a/Documentation/userspace-api/media/Makefile
+++ b/Documentation/userspace-api/media/Makefile
@@ -13,11 +13,11 @@ FILES = audio.h.rst ca.h.rst dmx.h.rst frontend.h.rst net.h.rst video.h.rst \
 TARGETS := $(addprefix $(BUILDDIR)/, $(FILES))
 
 gen_rst = \
-	echo ${PARSER} $< $@ $(SRC_DIR)/$(notdir $@).exceptions; \
-	${PARSER} $< $@ $(SRC_DIR)/$(notdir $@).exceptions
+	echo $(PERL) ${PARSER} $< $@ $(SRC_DIR)/$(notdir $@).exceptions; \
+	$(PERL) ${PARSER} $< $@ $(SRC_DIR)/$(notdir $@).exceptions
 
 quiet_gen_rst = echo '  PARSE   $(patsubst $(srctree)/%,%,$<)'; \
-	${PARSER} $< $@ $(SRC_DIR)/$(notdir $@).exceptions
+	$(PERL) ${PARSER} $< $@ $(SRC_DIR)/$(notdir $@).exceptions
 
 silent_gen_rst = ${gen_rst}
 
-- 
2.26.2