[PATCH 5.10 06/37] kbuild: Fix include path in scripts/Makefile.modpost

From: Greg Kroah-Hartman
Date: Fri Sep 02 2022 - 08:57:29 EST

From: Jing Leng <jleng@xxxxxxxxxxxxx>

commit 23a0cb8e3225122496bfa79172005c587c2d64bf upstream.

When building an external module, if users don't need to separate the
compilation output and source code, they run the following command:
"make -C $(LINUX_SRC_DIR) M=$(PWD)". At this point, "$(KBUILD_EXTMOD)"
and "$(src)" are the same.

If they need to separate them, they run "make -C $(KERNEL_SRC_DIR)
O=$(KERNEL_OUT_DIR) M=$(OUT_DIR) src=$(PWD)". Before running the
command, they need to copy "Kbuild" or "Makefile" to "$(OUT_DIR)" to
prevent compilation failure.

So the kernel should change the included path to avoid the copy operation.

Signed-off-by: Jing Leng <jleng@xxxxxxxxxxxxx>
[masahiro: I do not think "M=$(OUT_DIR) src=$(PWD)" is the official way,
but this patch is a nice clean up anyway.]
Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
Signed-off-by: Nicolas Schier <n.schier@xxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
scripts/Makefile.modpost | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

--- a/scripts/Makefile.modpost
+++ b/scripts/Makefile.modpost
@@ -87,8 +87,7 @@ obj := $(KBUILD_EXTMOD)
src := $(obj)

# Include the module's Makefile to find KBUILD_EXTRA_SYMBOLS
-include $(if $(wildcard $(KBUILD_EXTMOD)/Kbuild), \
- $(KBUILD_EXTMOD)/Kbuild, $(KBUILD_EXTMOD)/Makefile)
+include $(if $(wildcard $(src)/Kbuild), $(src)/Kbuild, $(src)/Makefile)

# modpost option for external modules