kbuild: prefix $(srctree)/ to some included Makefiles

VPATH is used in Kbuild to make pattern rules search for prerequisites
in both $(objtree) and $(srctree). Some of *.c, *.S files are not real
sources, but generated by tools such as flex, bison, perl.

In contrast, I doubt the benefit of --include-dir=$(abs_srctree) because
it is always clear which Makefiles are real sources, and which are not.

So, my hope is to add $(srctree)/ prefix to all check-in Makefiles,
then remove --include-dir=$(abs_srctree) flag in the future.

I am touching only some Kbuild core parts for now. Treewide fixes will
be needed to achieve this goal.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Makefile

@@ -339,14 +339,14 @@ __build_one_by_one:
 
 else # !mixed-build
 
-include scripts/Kbuild.include
+include $(srctree)/scripts/Kbuild.include
 
 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
 
-include scripts/subarch.include
+include $(srctree)/scripts/subarch.include
 
 # Cross compiling and selecting different set of gcc/bin-utils
 # ---------------------------------------------------------------------------
@@ -592,7 +592,7 @@ ifdef config-build
 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
 # KBUILD_DEFCONFIG may point out an alternative default configuration
 # used for 'make defconfig'
-include arch/$(SRCARCH)/Makefile
+include $(srctree)/arch/$(SRCARCH)/Makefile
 export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
 
 config: outputmakefile scripts_basic FORCE
@@ -679,7 +679,7 @@ RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc
 export RETPOLINE_CFLAGS
 export RETPOLINE_VDSO_CFLAGS
 
-include arch/$(SRCARCH)/Makefile
+include $(srctree)/arch/$(SRCARCH)/Makefile
 
 ifdef need-config
 ifdef may-sync-config

scripts/Makefile.asm-generic

@@ -14,10 +14,10 @@ src := $(subst /generated,,$(obj))
 
 # $(generic)/Kbuild lists mandatory-y. Exclude um since it is a special case.
 ifneq ($(SRCARCH),um)
-include $(generic)/Kbuild
+include $(srctree)/$(generic)/Kbuild
 endif
 
-include scripts/Kbuild.include
+include $(srctree)/scripts/Kbuild.include
 
 redundant := $(filter $(mandatory-y) $(generated-y), $(generic-y))
 redundant += $(foreach f, $(generic-y), $(if $(wildcard $(srctree)/$(src)/$(f)),$(f)))

scripts/Makefile.build

@@ -35,27 +35,27 @@ subdir-ccflags-y :=
 # Read auto.conf if it exists, otherwise ignore
 -include include/config/auto.conf
 
-include scripts/Kbuild.include
+include $(srctree)/scripts/Kbuild.include
 
 # The filename Kbuild has precedence over Makefile
 kbuild-dir := $(if $(filter /%,$(src)),$(src),$(srctree)/$(src))
 kbuild-file := $(if $(wildcard $(kbuild-dir)/Kbuild),$(kbuild-dir)/Kbuild,$(kbuild-dir)/Makefile)
 include $(kbuild-file)
 
-include scripts/Makefile.lib
+include $(srctree)/scripts/Makefile.lib
 
 # Do not include hostprogs rules unless needed.
 # $(sort ...) is used here to remove duplicated words and excessive spaces.
 hostprogs := $(sort $(hostprogs))
 ifneq ($(hostprogs),)
-include scripts/Makefile.host
+include $(srctree)/scripts/Makefile.host
 endif
 
 # Do not include userprogs rules unless needed.
 # $(sort ...) is used here to remove duplicated words and excessive spaces.
 userprogs := $(sort $(userprogs))
 ifneq ($(userprogs),)
-include scripts/Makefile.userprogs
+include $(srctree)/scripts/Makefile.userprogs
 endif
 
 ifndef obj

scripts/Makefile.clean

@@ -8,7 +8,7 @@ src := $(obj)
 PHONY := __clean
 __clean:
 
-include scripts/Kbuild.include
+include $(srctree)/scripts/Kbuild.include
 
 # The filename Kbuild has precedence over Makefile
 kbuild-dir := $(if $(filter /%,$(src)),$(src),$(srctree)/$(src))

scripts/Makefile.dtbinst

@@ -14,7 +14,7 @@ PHONY := __dtbs_install
 __dtbs_install:
 
 include include/config/auto.conf
-include scripts/Kbuild.include
+include $(srctree)/scripts/Kbuild.include
 include $(src)/Makefile
 
 dtbs    := $(addprefix $(dst)/, $(dtb-y) $(if $(CONFIG_OF_ALL_DTBS),$(dtb-)))

scripts/Makefile.headersinst

@@ -12,7 +12,7 @@
 PHONY := __headers
 __headers:
 
-include scripts/Kbuild.include
+include $(srctree)/scripts/Kbuild.include
 
 src := $(srctree)/$(obj)
 gen := $(objtree)/$(subst include/,include/generated/,$(obj))

scripts/Makefile.modinst

@@ -6,7 +6,7 @@
 PHONY := __modinst
 __modinst:
 
-include scripts/Kbuild.include
+include $(srctree)/scripts/Kbuild.include
 
 modules := $(sort $(shell cat $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)modules.order))
 

scripts/Makefile.modpost

@@ -41,10 +41,10 @@ PHONY := __modpost
 __modpost:
 
 include include/config/auto.conf
-include scripts/Kbuild.include
+include $(srctree)/scripts/Kbuild.include
 
 # for ld_flags
-include scripts/Makefile.lib
+include $(srctree)/scripts/Makefile.lib
 
 MODPOST = scripts/mod/modpost								\
 	$(if $(CONFIG_MODVERSIONS),-m)							\

scripts/Makefile.modsign

@@ -6,7 +6,7 @@
 PHONY := __modsign
 __modsign:
 
-include scripts/Kbuild.include
+include $(srctree)/scripts/Kbuild.include
 
 modules := $(sort $(shell cat modules.order))