[PATCH 6.1 086/197] modpost: propagate W=1 build option to modpost

Greg Kroah-Hartman
2024-02-20T21:02:23Z

From: Masahiro Yamada <masahiroy@kernel.org>

commit 20ff36856fe00879f82de71fe6f1482ca1b72334 upstream.

"No build warning" is a strong requirement these days, so you must fix
all issues before enabling a new warning flag.

We often add a new warning to W=1 first so that the kbuild test robot
blocks new breakages.

This commit allows modpost to show extra warnings only when W=1
(or KBUILD_EXTRA_WARN=1) is given.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Stable-dep-of: 846cfbeed09b ("um: Fix adding '-no-pie' for clang")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
scripts/Makefile.modpost | 1 +
scripts/mod/modpost.c | 7 ++++++-
2 files changed, 7 insertions(+), 1 deletion(-)

--- a/scripts/Makefile.modpost
+++ b/scripts/Makefile.modpost
@@ -44,6 +44,7 @@ modpost-args = \
$(if $(CONFIG_SECTION_MISMATCH_WARN_ONLY),,-E) \
$(if $(KBUILD_NSDEPS),-d $(MODULES_NSDEPS)) \
$(if $(CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS)$(KBUILD_NSDEPS),-N) \
+ $(if $(findstring 1, $(KBUILD_EXTRA_WARN)),-W) \
-o $@

# 'make -i -k' ignores compile errors, and builds as many modules as possible.
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -41,6 +41,8 @@ static bool allow_missing_ns_imports;

static bool error_occurred;

+static bool extra_warn;
+
/*
* Cut off the warnings when there are too many. This typically occurs when
* vmlinux is missing. ('make modules' without building vmlinux.)
@@ -2290,7 +2292,7 @@ int main(int argc, char **argv)
LIST_HEAD(dump_lists);
struct dump_list *dl, *dl2;

- while ((opt = getopt(argc, argv, "ei:mnT:o:awENd:")) != -1) {
+ while ((opt = getopt(argc, argv, "ei:mnT:o:aWwENd:")) != -1) {
switch (opt) {
case 'e':
external_module = true;
@@ -2315,6 +2317,9 @@ int main(int argc, char **argv)
case 'T':
files_source = optarg;
break;
+ case 'W':
+ extra_warn = true;
+ break;
case 'w':
warn_unresolved = true;
break;