From: Jing Leng jleng@ambarella.com
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 "$(OUT_DIR)" to prevent compilation failure.
So the kernel should change the included path to avoid the copy operation.
Signed-off-by: Jing Leng jleng@ambarella.com [masahiro: I do not think "M=$(OUT_DIR) src=$(PWD)" is the official way, but this patch is a nice clean up anyway.] Signed-off-by: Masahiro Yamada masahiroy@kernel.org [nsc: updated context for v4.19] Signed-off-by: Nicolas Schier n.schier@avm.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- scripts/Makefile.modpost | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)
--- a/scripts/Makefile.modpost +++ b/scripts/Makefile.modpost @@ -75,8 +75,7 @@ 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) endif
MODPOST += $(subst -i,-n,$(filter -i,$(MAKEFLAGS))) -s -T - $(wildcard vmlinux)