kbuild: use $(src) instead of $(srctree)/$(src) for source directory

Kbuild conventionally uses $(obj)/ for generated files, and $(src)/ for
checked-in source files. It is merely a convention without any functional
difference. In fact, $(obj) and $(src) are exactly the same, as defined
in scripts/Makefile.build:

    src := $(obj)

When the kernel is built in a separate output directory, $(src) does
not accurately reflect the source directory location. While Kbuild
resolves this discrepancy by specifying VPATH=$(srctree) to search for
source files, it does not cover all cases. For example, when adding a
header search path for local headers, -I$(srctree)/$(src) is typically
passed to the compiler.

This introduces inconsistency between upstream and downstream Makefiles
because $(src) is used instead of $(srctree)/$(src) for the latter.

To address this inconsistency, this commit changes the semantics of
$(src) so that it always points to the directory in the source tree.

Going forward, the variables used in Makefiles will have the following
meanings:

  $(obj)     - directory in the object tree
  $(src)     - directory in the source tree  (changed by this commit)
  $(objtree) - the top of the kernel object tree
  $(srctree) - the top of the kernel source tree

Consequently, $(srctree)/$(src) in upstream Makefiles need to be replaced
with $(src).
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>

Documentation/Makefile

@@ -76,22 +76,22 @@ loop_cmd = $(echo-cmd) $(cmd_$(1)) || exit;
 #    * dest folder relative to $(BUILDDIR) and
 #    * cache folder relative to $(BUILDDIR)/.doctrees
 # $4 dest subfolder e.g. "man" for man pages at userspace-api/media/man
-# $5 reST source folder relative to $(srctree)/$(src),
+# $5 reST source folder relative to $(src),
 #    e.g. "userspace-api/media" for the linux-tv book-set at ./Documentation/userspace-api/media
 
 quiet_cmd_sphinx = SPHINX  $@ --> file://$(abspath $(BUILDDIR)/$3/$4)
       cmd_sphinx = $(MAKE) BUILDDIR=$(abspath $(BUILDDIR)) $(build)=Documentation/userspace-api/media $2 && \
 	PYTHONDONTWRITEBYTECODE=1 \
-	BUILDDIR=$(abspath $(BUILDDIR)) SPHINX_CONF=$(abspath $(srctree)/$(src)/$5/$(SPHINX_CONF)) \
+	BUILDDIR=$(abspath $(BUILDDIR)) SPHINX_CONF=$(abspath $(src)/$5/$(SPHINX_CONF)) \
 	$(PYTHON3) $(srctree)/scripts/jobserver-exec \
 	$(CONFIG_SHELL) $(srctree)/Documentation/sphinx/parallel-wrapper.sh \
 	$(SPHINXBUILD) \
 	-b $2 \
-	-c $(abspath $(srctree)/$(src)) \
+	-c $(abspath $(src)) \
 	-d $(abspath $(BUILDDIR)/.doctrees/$3) \
 	-D version=$(KERNELVERSION) -D release=$(KERNELRELEASE) \
 	$(ALLSPHINXOPTS) \
-	$(abspath $(srctree)/$(src)/$5) \
+	$(abspath $(src)/$5) \
 	$(abspath $(BUILDDIR)/$3/$4) && \
 	if [ "x$(DOCS_CSS)" != "x" ]; then \
 		cp $(if $(patsubst /%,,$(DOCS_CSS)),$(abspath $(srctree)/$(DOCS_CSS)),$(DOCS_CSS)) $(BUILDDIR)/$3/_static/; \

Documentation/devicetree/bindings/Makefile

@@ -25,7 +25,7 @@ quiet_cmd_extract_ex = DTEX    $@
 $(obj)/%.example.dts: $(src)/%.yaml check_dtschema_version FORCE
 	$(call if_changed,extract_ex)
 
-find_all_cmd = find $(srctree)/$(src) \( -name '*.yaml' ! \
+find_all_cmd = find $(src) \( -name '*.yaml' ! \
 		-name 'processed-schema*' \)
 
 find_cmd = $(find_all_cmd) | \
@@ -37,12 +37,12 @@ CHK_DT_EXAMPLES := $(patsubst $(srctree)/%.yaml,%.example.dtb, $(shell $(find_cm
 quiet_cmd_yamllint = LINT    $(src)
       cmd_yamllint = ($(find_cmd) | \
                      xargs -n200 -P$$(nproc) \
-		     $(DT_SCHEMA_LINT) -f parsable -c $(srctree)/$(src)/.yamllint >&2) \
+		     $(DT_SCHEMA_LINT) -f parsable -c $(src)/.yamllint >&2) \
 		     && touch $@ || true
 
 quiet_cmd_chk_bindings = CHKDT   $(src)
       cmd_chk_bindings = ($(find_cmd) | \
-			  xargs -n200 -P$$(nproc) $(DT_DOC_CHECKER) -u $(srctree)/$(src)) \
+			  xargs -n200 -P$$(nproc) $(DT_DOC_CHECKER) -u $(src)) \
 			  && touch $@ || true
 
 quiet_cmd_mk_schema = SCHEMA  $@

Documentation/kbuild/makefiles.rst

@@ -346,7 +346,7 @@ ccflags-y, asflags-y and ldflags-y
   Example::
 
     #arch/cris/boot/compressed/Makefile
-    ldflags-y += -T $(srctree)/$(src)/decompress_$(arch-y).lds
+    ldflags-y += -T $(src)/decompress_$(arch-y).lds
 
 subdir-ccflags-y, subdir-asflags-y
   The two flags listed above are similar to ccflags-y and asflags-y.
@@ -426,14 +426,14 @@ path to prerequisite files and target files.
 Two variables are used when defining custom rules:
 
 $(src)
-  $(src) is a relative path which points to the directory
-  where the Makefile is located. Always use $(src) when
+  $(src) is the directory where the Makefile is located. Always use $(src) when
   referring to files located in the src tree.
 
 $(obj)
-  $(obj) is a relative path which points to the directory
-  where the target is saved. Always use $(obj) when
-  referring to generated files.
+  $(obj) is the directory where the target is saved. Always use $(obj) when
+  referring to generated files. Use $(obj) for pattern rules that need to work
+  for both generated files and real sources (VPATH will help to find the
+  prerequisites not only in the object tree but also in the source tree).
 
   Example::
 

Makefile

@@ -263,7 +263,14 @@ srctree := $(abs_srctree)
 endif
 
 objtree		:= .
+
+VPATH		:=
+
+ifeq ($(KBUILD_EXTMOD),)
+ifdef building_out_of_srctree
 VPATH		:= $(srctree)
+endif
+endif
 
 export building_out_of_srctree srctree objtree VPATH
 

arch/arc/boot/dts/Makefile

@@ -10,8 +10,7 @@ obj-y   += $(builtindtb-y).dtb.o
 dtb-y := $(builtindtb-y).dtb
 
 # for CONFIG_OF_ALL_DTBS test
-dtstree	:= $(srctree)/$(src)
-dtb-	:= $(patsubst $(dtstree)/%.dts,%.dtb, $(wildcard $(dtstree)/*.dts))
+dtb-	:= $(patsubst $(src)/%.dts,%.dtb, $(wildcard $(src)/*.dts))
 
 # board-specific dtc flags
 DTC_FLAGS_hsdk += --pad 20

arch/arm/Kbuild

 # SPDX-License-Identifier: GPL-2.0-only
 obj-$(CONFIG_FPE_NWFPE)		+= nwfpe/
 # Put arch/arm/fastfpe/ to use this.
-obj-$(CONFIG_FPE_FASTFPE)	+= $(patsubst $(srctree)/$(src)/%,%,$(wildcard $(srctree)/$(src)/fastfpe/))
+obj-$(CONFIG_FPE_FASTFPE)	+= $(patsubst $(src)/%,%,$(wildcard $(src)/fastfpe/))
 obj-$(CONFIG_VFP)		+= vfp/
 obj-$(CONFIG_XEN)		+= xen/
 obj-$(CONFIG_VDSO)		+= vdso/

arch/arm/boot/Makefile

@@ -25,8 +25,7 @@ targets := Image zImage xipImage bootpImage uImage
 
 ifeq ($(CONFIG_XIP_KERNEL),y)
 
-cmd_deflate_xip_data = $(CONFIG_SHELL) -c \
-	'$(srctree)/$(src)/deflate_xip_data.sh $< $@'
+cmd_deflate_xip_data = $(CONFIG_SHELL) -c '$(src)/deflate_xip_data.sh $< $@'
 
 ifeq ($(CONFIG_XIP_DEFLATED_DATA),y)
 quiet_cmd_mkxip = XIPZ    $@

arch/arm/mach-s3c/Makefile

@@ -2,7 +2,7 @@
 #
 # Copyright 2009 Simtec Electronics
 
-include $(srctree)/$(src)/Makefile.s3c64xx
+include $(src)/Makefile.s3c64xx
 
 # Objects we always build independent of SoC choice
 

arch/arm/plat-orion/Makefile

@@ -2,7 +2,7 @@
 #
 # Makefile for the linux kernel.
 #
-ccflags-y := -I$(srctree)/$(src)/include
+ccflags-y := -I$(src)/include
 
 orion-gpio-$(CONFIG_GPIOLIB)      += gpio.o
 obj-$(CONFIG_PLAT_ORION_LEGACY)   += irq.o pcie.o time.o common.o mpp.o

arch/arm/tools/Makefile

@@ -9,7 +9,7 @@ gen := arch/$(ARCH)/include/generated
 kapi := $(gen)/asm
 uapi := $(gen)/uapi/asm
 syshdr := $(srctree)/scripts/syscallhdr.sh
-sysnr := $(srctree)/$(src)/syscallnr.sh
+sysnr := $(src)/syscallnr.sh
 systbl := $(srctree)/scripts/syscalltbl.sh
 syscall := $(src)/syscall.tbl
 

arch/arm64/kernel/vdso/Makefile

@@ -68,7 +68,7 @@ $(obj)/%.so: $(obj)/%.so.dbg FORCE
 	$(call if_changed,objcopy)
 
 # Generate VDSO offsets using helper script
-gen-vdsosym := $(srctree)/$(src)/gen_vdso_offsets.sh
+gen-vdsosym := $(src)/gen_vdso_offsets.sh
 quiet_cmd_vdsosym = VDSOSYM $@
       cmd_vdsosym = $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@
 

arch/arm64/kvm/Makefile

@@ -3,7 +3,7 @@
 # Makefile for Kernel-based Virtual Machine module
 #
 
-ccflags-y += -I $(srctree)/$(src)
+ccflags-y += -I $(src)
 
 include $(srctree)/virt/kvm/Makefile.kvm
 
@@ -30,7 +30,7 @@ define rule_gen_hyp_constants
 	$(call filechk,offsets,__HYP_CONSTANTS_H__)
 endef
 
-CFLAGS_hyp-constants.o = -I $(srctree)/$(src)/hyp/include
+CFLAGS_hyp-constants.o = -I $(src)/hyp/include
 $(obj)/hyp-constants.s: $(src)/hyp/hyp-constants.c FORCE
 	$(call if_changed_dep,cc_s_c)
 

arch/arm64/kvm/hyp/Makefile

@@ -3,7 +3,7 @@
 # Makefile for Kernel-based Virtual Machine module, HYP part
 #
 
-incdir := $(srctree)/$(src)/include
+incdir := $(src)/include
 subdir-asflags-y := -I$(incdir)
 subdir-ccflags-y := -I$(incdir)
 

arch/csky/boot/dts/Makefile

 # SPDX-License-Identifier: GPL-2.0-only
-dtstree	:= $(srctree)/$(src)
-
-dtb-y := $(patsubst $(dtstree)/%.dts,%.dtb, $(wildcard $(dtstree)/*.dts))
+dtb-y := $(patsubst $(src)/%.dts,%.dtb, $(wildcard $(src)/*.dts))

arch/csky/kernel/vdso/Makefile

@@ -57,4 +57,4 @@ quiet_cmd_vdsold = VDSOLD  $@
 # Extracts symbol offsets from the VDSO, converting them into an assembly file
 # that contains the same symbols at the same offsets.
 quiet_cmd_so2s = SO2S    $@
-      cmd_so2s = $(NM) -D $< | $(srctree)/$(src)/so2s.sh > $@
+      cmd_so2s = $(NM) -D $< | $(src)/so2s.sh > $@

arch/loongarch/kvm/Makefile

@@ -3,7 +3,7 @@
 # Makefile for LoongArch KVM support
 #
 
-ccflags-y += -I $(srctree)/$(src)
+ccflags-y += -I $(src)
 
 include $(srctree)/virt/kvm/Makefile.kvm
 

arch/loongarch/vdso/Makefile

@@ -52,7 +52,7 @@ quiet_cmd_vdsoas_o_S = AS       $@
       cmd_vdsoas_o_S = $(CC) $(a_flags) -c -o $@ $<
 
 # Generate VDSO offsets using helper script
-gen-vdsosym := $(srctree)/$(src)/gen_vdso_offsets.sh
+gen-vdsosym := $(src)/gen_vdso_offsets.sh
 quiet_cmd_vdsosym = VDSOSYM $@
       cmd_vdsosym = $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@
 

arch/mips/kernel/syscalls/Makefile

@@ -5,7 +5,7 @@ uapi := arch/$(SRCARCH)/include/generated/uapi/asm
 $(shell mkdir -p $(uapi) $(kapi))
 
 syshdr := $(srctree)/scripts/syscallhdr.sh
-sysnr := $(srctree)/$(src)/syscallnr.sh
+sysnr := $(src)/syscallnr.sh
 systbl := $(srctree)/scripts/syscalltbl.sh
 
 quiet_cmd_syshdr = SYSHDR  $@

arch/mips/vdso/Makefile

@@ -43,8 +43,8 @@ CFLAGS_vgettimeofday.o = -include $(c-gettimeofday-y)
 # config-n32-o32-env.c prepares the environment to build a 32bit vDSO
 # library on a 64bit kernel.
 # Note: Needs to be included before than the generic library.
-CFLAGS_vgettimeofday-o32.o = -include $(srctree)/$(src)/config-n32-o32-env.c -include $(c-gettimeofday-y)
-CFLAGS_vgettimeofday-n32.o = -include $(srctree)/$(src)/config-n32-o32-env.c -include $(c-gettimeofday-y)
+CFLAGS_vgettimeofday-o32.o = -include $(src)/config-n32-o32-env.c -include $(c-gettimeofday-y)
+CFLAGS_vgettimeofday-n32.o = -include $(src)/config-n32-o32-env.c -include $(c-gettimeofday-y)
 endif
 
 CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE)

arch/nios2/boot/dts/Makefile

@@ -2,5 +2,4 @@
 
 obj-y := $(patsubst %.dts,%.dtb.o,$(CONFIG_NIOS2_DTB_SOURCE))
 
-dtstree		:= $(srctree)/$(src)
-dtb-$(CONFIG_OF_ALL_DTBS) := $(patsubst $(dtstree)/%.dts,%.dtb, $(wildcard $(dtstree)/*.dts))
+dtb-$(CONFIG_OF_ALL_DTBS) := $(patsubst $(src)/%.dts,%.dtb, $(wildcard $(src)/*.dts))

arch/parisc/kernel/vdso32/Makefile

@@ -40,7 +40,7 @@ quiet_cmd_vdso32as = VDSO32A $@
       cmd_vdso32as = $(CROSS32CC) $(a_flags) -c -o $@ $<
 
 # Generate VDSO offsets using helper script
-gen-vdsosym := $(srctree)/$(src)/gen_vdso_offsets.sh
+gen-vdsosym := $(src)/gen_vdso_offsets.sh
 quiet_cmd_vdsosym = VDSOSYM $@
 	cmd_vdsosym = $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@
 

arch/parisc/kernel/vdso64/Makefile

@@ -40,7 +40,7 @@ quiet_cmd_vdso64as = VDSO64A $@
       cmd_vdso64as = $(CC) $(a_flags) -c -o $@ $<
 
 # Generate VDSO offsets using helper script
-gen-vdsosym := $(srctree)/$(src)/gen_vdso_offsets.sh
+gen-vdsosym := $(src)/gen_vdso_offsets.sh
 quiet_cmd_vdsosym = VDSOSYM $@
 	cmd_vdsosym = $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@
 

arch/powerpc/boot/Makefile

@@ -218,7 +218,7 @@ $(addprefix $(obj)/,$(libfdt) $(libfdtheader)): $(obj)/%: $(srctree)/scripts/dtc
 $(obj)/empty.c:
 	$(Q)touch $@
 
-$(obj)/zImage.coff.lds $(obj)/zImage.ps3.lds : $(obj)/%: $(srctree)/$(src)/%.S
+$(obj)/zImage.coff.lds $(obj)/zImage.ps3.lds : $(obj)/%: $(src)/%.S
 	$(Q)cp $< $@
 
 clean-files := $(zlib-) $(zlibheader-) $(zliblinuxheader-) \
@@ -252,9 +252,9 @@ targets		+= $(patsubst $(obj)/%,%,$(obj-boot) wrapper.a) zImage.lds
 extra-y		:= $(obj)/wrapper.a $(obj-plat) $(obj)/empty.o \
 		   $(obj)/zImage.lds $(obj)/zImage.coff.lds $(obj)/zImage.ps3.lds
 
-dtstree		:= $(srctree)/$(src)/dts
+dtstree		:= $(src)/dts
 
-wrapper		:=$(srctree)/$(src)/wrapper
+wrapper		:= $(src)/wrapper
 wrapperbits	:= $(extra-y) $(addprefix $(obj)/,addnote hack-coff mktree) \
 			$(wrapper) FORCE
 

arch/powerpc/boot/dts/Makefile

@@ -2,5 +2,4 @@
 
 subdir-y += fsl
 
-dtstree		:= $(srctree)/$(src)
-dtb-$(CONFIG_OF_ALL_DTBS) := $(patsubst $(dtstree)/%.dts,%.dtb, $(wildcard $(dtstree)/*.dts))
+dtb-$(CONFIG_OF_ALL_DTBS) := $(patsubst $(src)/%.dts,%.dtb, $(wildcard $(src)/*.dts))

arch/powerpc/boot/dts/fsl/Makefile

 # SPDX-License-Identifier: GPL-2.0
 
-dtstree		:= $(srctree)/$(src)
-dtb-$(CONFIG_OF_ALL_DTBS) := $(patsubst $(dtstree)/%.dts,%.dtb, $(wildcard $(dtstree)/*.dts))
+dtb-$(CONFIG_OF_ALL_DTBS) := $(patsubst $(src)/%.dts,%.dtb, $(wildcard $(src)/*.dts))

arch/powerpc/kernel/vdso/Makefile

@@ -90,10 +90,10 @@ $(obj)/vgettimeofday-64.o: %-64.o: %.c FORCE
 	$(call if_changed_dep,cc_o_c)
 
 # Generate VDSO offsets using helper script
-gen-vdso32sym := $(srctree)/$(src)/gen_vdso32_offsets.sh
+gen-vdso32sym := $(src)/gen_vdso32_offsets.sh
 quiet_cmd_vdso32sym = VDSO32SYM $@
       cmd_vdso32sym = $(NM) $< | $(gen-vdso32sym) | LC_ALL=C sort > $@
-gen-vdso64sym := $(srctree)/$(src)/gen_vdso64_offsets.sh
+gen-vdso64sym := $(src)/gen_vdso64_offsets.sh
 quiet_cmd_vdso64sym = VDSO64SYM $@
       cmd_vdso64sym = $(NM) $< | $(gen-vdso64sym) | LC_ALL=C sort > $@
 

arch/riscv/kernel/compat_vdso/Makefile

@@ -58,7 +58,7 @@ $(obj)/%.so: $(obj)/%.so.dbg FORCE
 	$(call if_changed,objcopy)
 
 # Generate VDSO offsets using helper script
-gen-compat_vdsosym := $(srctree)/$(src)/gen_compat_vdso_offsets.sh
+gen-compat_vdsosym := $(src)/gen_compat_vdso_offsets.sh
 quiet_cmd_compat_vdsosym = VDSOSYM $@
 	cmd_compat_vdsosym = $(NM) $< | $(gen-compat_vdsosym) | LC_ALL=C sort > $@
 

arch/riscv/kernel/vdso/Makefile

@@ -60,7 +60,7 @@ $(obj)/%.so: $(obj)/%.so.dbg FORCE
 	$(call if_changed,objcopy)
 
 # Generate VDSO offsets using helper script
-gen-vdsosym := $(srctree)/$(src)/gen_vdso_offsets.sh
+gen-vdsosym := $(src)/gen_vdso_offsets.sh
 quiet_cmd_vdsosym = VDSOSYM $@
 	cmd_vdsosym = $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@
 

arch/riscv/kvm/Makefile

@@ -3,7 +3,7 @@
 # Makefile for RISC-V KVM support
 #
 
-ccflags-y += -I $(srctree)/$(src)
+ccflags-y += -I $(src)
 
 include $(srctree)/virt/kvm/Makefile.kvm
 

arch/s390/kernel/syscalls/Makefile

@@ -4,8 +4,8 @@ gen	:= arch/$(ARCH)/include/generated
 kapi	:= $(gen)/asm
 uapi	:= $(gen)/uapi/asm
 
-syscall	:= $(srctree)/$(src)/syscall.tbl
-systbl	:= $(srctree)/$(src)/syscalltbl
+syscall	:= $(src)/syscall.tbl
+systbl	:= $(src)/syscalltbl
 
 gen-y := $(kapi)/syscall_table.h
 kapi-hdrs-y := $(kapi)/unistd_nr.h

arch/s390/kernel/vdso32/Makefile

@@ -62,7 +62,7 @@ quiet_cmd_vdso32cc = VDSO32C $@
       cmd_vdso32cc = $(CC) $(c_flags) -c -o $@ $<
 
 # Generate VDSO offsets using helper script
-gen-vdsosym := $(srctree)/$(src)/gen_vdso_offsets.sh
+gen-vdsosym := $(src)/gen_vdso_offsets.sh
 quiet_cmd_vdsosym = VDSOSYM $@
 	cmd_vdsosym = $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@
 

arch/s390/kernel/vdso64/Makefile

@@ -72,7 +72,7 @@ quiet_cmd_vdso64cc = VDSO64C $@
       cmd_vdso64cc = $(CC) $(c_flags) -c -o $@ $<
 
 # Generate VDSO offsets using helper script
-gen-vdsosym := $(srctree)/$(src)/gen_vdso_offsets.sh
+gen-vdsosym := $(src)/gen_vdso_offsets.sh
 quiet_cmd_vdsosym = VDSOSYM $@
 	cmd_vdsosym = $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@
 

arch/sparc/vdso/Makefile

@@ -103,7 +103,7 @@ quiet_cmd_vdso = VDSO    $@
       cmd_vdso = $(LD) -nostdlib -o $@ \
 		       $(VDSO_LDFLAGS) $(VDSO_LDFLAGS_$(filter %.lds,$(^F))) \
 		       -T $(filter %.lds,$^) $(filter %.o,$^) && \
-		sh $(srctree)/$(src)/checkundef.sh '$(OBJDUMP)' '$@'
+		sh $(src)/checkundef.sh '$(OBJDUMP)' '$@'
 
 VDSO_LDFLAGS = -shared --hash-style=both --build-id=sha1 -Bsymbolic
 GCOV_PROFILE := n

arch/um/kernel/Makefile

@@ -47,7 +47,7 @@ $(obj)/config.c: $(src)/config.c.in $(obj)/config.tmp FORCE
 	$(call if_changed,quote2)
 
 quiet_cmd_mkcapflags = MKCAP   $@
-      cmd_mkcapflags = $(CONFIG_SHELL) $(srctree)/$(src)/../../x86/kernel/cpu/mkcapflags.sh $@ $^
+      cmd_mkcapflags = $(CONFIG_SHELL) $(src)/../../x86/kernel/cpu/mkcapflags.sh $@ $^
 
 cpufeature = $(src)/../../x86/include/asm/cpufeatures.h
 vmxfeature = $(src)/../../x86/include/asm/vmxfeatures.h

arch/x86/boot/Makefile

@@ -129,7 +129,7 @@ targets += mtools.conf
 # genimage.sh requires bash, but it also has a bunch of other
 # external dependencies.
 quiet_cmd_genimage = GENIMAGE $3
-cmd_genimage = $(BASH) $(srctree)/$(src)/genimage.sh $2 $3 $(obj)/bzImage \
+      cmd_genimage = $(BASH) $(src)/genimage.sh $2 $3 $(obj)/bzImage \
 		$(obj)/mtools.conf '$(FDARGS)' $(FDINITRD)
 
 PHONY += bzdisk fdimage fdimage144 fdimage288 hdimage isoimage

arch/x86/entry/vdso/Makefile

@@ -176,7 +176,7 @@ quiet_cmd_vdso = VDSO    $@
       cmd_vdso = $(LD) -o $@ \
 		       $(VDSO_LDFLAGS) $(VDSO_LDFLAGS_$(filter %.lds,$(^F))) \
 		       -T $(filter %.lds,$^) $(filter %.o,$^) && \
-		 sh $(srctree)/$(src)/checkundef.sh '$(NM)' '$@'
+		 sh $(src)/checkundef.sh '$(NM)' '$@'
 
 VDSO_LDFLAGS = -shared --hash-style=both --build-id=sha1 \
 	$(call ld-option, --eh-frame-hdr) -Bsymbolic -z noexecstack

arch/x86/kernel/Makefile

@@ -40,7 +40,7 @@ KMSAN_SANITIZE_sev.o					:= n
 KCOV_INSTRUMENT_head$(BITS).o				:= n
 KCOV_INSTRUMENT_sev.o					:= n
 
-CFLAGS_irq.o := -I $(srctree)/$(src)/../include/asm/trace
+CFLAGS_irq.o := -I $(src)/../include/asm/trace
 
 obj-y			+= head_$(BITS).o
 obj-y			+= head$(BITS).o

arch/x86/kernel/cpu/Makefile

@@ -60,7 +60,7 @@ obj-$(CONFIG_ACRN_GUEST)		+= acrn.o
 obj-$(CONFIG_DEBUG_FS)			+= debugfs.o
 
 quiet_cmd_mkcapflags = MKCAP   $@
-      cmd_mkcapflags = $(CONFIG_SHELL) $(srctree)/$(src)/mkcapflags.sh $@ $^
+      cmd_mkcapflags = $(CONFIG_SHELL) $(src)/mkcapflags.sh $@ $^
 
 cpufeature = $(src)/../../include/asm/cpufeatures.h
 vmxfeature = $(src)/../../include/asm/vmxfeatures.h

arch/x86/mm/Makefile

@@ -34,7 +34,7 @@ obj-y				+= pat/
 CFLAGS_physaddr.o		:= -fno-stack-protector
 CFLAGS_mem_encrypt_identity.o	:= -fno-stack-protector
 
-CFLAGS_fault.o := -I $(srctree)/$(src)/../include/asm/trace
+CFLAGS_fault.o := -I $(src)/../include/asm/trace
 
 obj-$(CONFIG_X86_32)		+= pgtable_32.o iomap_32.o
 

arch/x86/um/vdso/Makefile

@@ -63,7 +63,7 @@ quiet_cmd_vdso = VDSO    $@
       cmd_vdso = $(CC) -nostdlib -o $@ \
 		       $(CC_FLAGS_LTO) $(VDSO_LDFLAGS) $(VDSO_LDFLAGS_$(filter %.lds,$(^F))) \
 		       -Wl,-T,$(filter %.lds,$^) $(filter %.o,$^) && \
-		 sh $(srctree)/$(src)/checkundef.sh '$(NM)' '$@'
+		 sh $(src)/checkundef.sh '$(NM)' '$@'
 
 VDSO_LDFLAGS = -fPIC -shared -Wl,--hash-style=sysv -z noexecstack
 GCOV_PROFILE := n

arch/xtensa/boot/dts/Makefile

@@ -10,5 +10,4 @@
 obj-$(CONFIG_OF) += $(addsuffix .dtb.o, $(CONFIG_BUILTIN_DTB_SOURCE))
 
 # for CONFIG_OF_ALL_DTBS test
-dtstree	:= $(srctree)/$(src)
-dtb-	:= $(patsubst $(dtstree)/%.dts,%.dtb, $(wildcard $(dtstree)/*.dts))
+dtb-	:= $(patsubst $(src)/%.dts,%.dtb, $(wildcard $(src)/*.dts))

certs/Makefile

@@ -13,7 +13,7 @@ CFLAGS_blacklist_hashes.o := -I $(obj)
 quiet_cmd_check_and_copy_blacklist_hash_list = GEN     $@
       cmd_check_and_copy_blacklist_hash_list = \
 	$(if $(CONFIG_SYSTEM_BLACKLIST_HASH_LIST), \
-	$(AWK) -f $(srctree)/$(src)/check-blacklist-hashes.awk $(CONFIG_SYSTEM_BLACKLIST_HASH_LIST) >&2; \
+	$(AWK) -f $(src)/check-blacklist-hashes.awk $(CONFIG_SYSTEM_BLACKLIST_HASH_LIST) >&2; \
 	{ cat $(CONFIG_SYSTEM_BLACKLIST_HASH_LIST); echo $(comma) NULL; } > $@, \
 	echo NULL > $@)
 
@@ -55,7 +55,7 @@ $(obj)/signing_key.pem: $(obj)/x509.genkey FORCE
 targets += signing_key.pem
 
 quiet_cmd_copy_x509_config = COPY    $@
-      cmd_copy_x509_config = cat $(srctree)/$(src)/default_x509.genkey > $@
+      cmd_copy_x509_config = cat $(src)/default_x509.genkey > $@
 
 # You can provide your own config file. If not present, copy the default one.
 $(obj)/x509.genkey:

drivers/Makefile

@@ -6,11 +6,6 @@
 # Rewritten to use lists instead of if-statements.
 #
 
-# Some driver Makefiles miss $(srctree)/ for include directive.
-ifdef building_out_of_srctree
-MAKEFLAGS += --include-dir=$(srctree)
-endif
-
 obj-y				+= cache/
 obj-y				+= irqchip/
 obj-y				+= bus/

drivers/crypto/intel/qat/qat_420xx/Makefile

 # SPDX-License-Identifier: GPL-2.0-only
-ccflags-y := -I $(srctree)/$(src)/../qat_common
+ccflags-y := -I $(src)/../qat_common
 obj-$(CONFIG_CRYPTO_DEV_QAT_420XX) += qat_420xx.o
 qat_420xx-objs := adf_drv.o adf_420xx_hw_data.o

drivers/crypto/intel/qat/qat_4xxx/Makefile

 # SPDX-License-Identifier: (BSD-3-Clause OR GPL-2.0-only)
-ccflags-y := -I $(srctree)/$(src)/../qat_common
+ccflags-y := -I $(src)/../qat_common
 obj-$(CONFIG_CRYPTO_DEV_QAT_4XXX) += qat_4xxx.o
 qat_4xxx-objs := adf_drv.o adf_4xxx_hw_data.o

drivers/crypto/intel/qat/qat_c3xxx/Makefile

 # SPDX-License-Identifier: GPL-2.0-only
-ccflags-y := -I $(srctree)/$(src)/../qat_common
+ccflags-y := -I $(src)/../qat_common
 obj-$(CONFIG_CRYPTO_DEV_QAT_C3XXX) += qat_c3xxx.o
 qat_c3xxx-objs := adf_drv.o adf_c3xxx_hw_data.o

drivers/crypto/intel/qat/qat_c3xxxvf/Makefile

 # SPDX-License-Identifier: GPL-2.0-only
-ccflags-y := -I $(srctree)/$(src)/../qat_common
+ccflags-y := -I $(src)/../qat_common
 obj-$(CONFIG_CRYPTO_DEV_QAT_C3XXXVF) += qat_c3xxxvf.o
 qat_c3xxxvf-objs := adf_drv.o adf_c3xxxvf_hw_data.o

drivers/crypto/intel/qat/qat_c62x/Makefile

 # SPDX-License-Identifier: GPL-2.0-only
-ccflags-y := -I $(srctree)/$(src)/../qat_common
+ccflags-y := -I $(src)/../qat_common
 obj-$(CONFIG_CRYPTO_DEV_QAT_C62X) += qat_c62x.o
 qat_c62x-objs := adf_drv.o adf_c62x_hw_data.o

drivers/crypto/intel/qat/qat_c62xvf/Makefile

 # SPDX-License-Identifier: GPL-2.0-only
-ccflags-y := -I $(srctree)/$(src)/../qat_common
+ccflags-y := -I $(src)/../qat_common
 obj-$(CONFIG_CRYPTO_DEV_QAT_C62XVF) += qat_c62xvf.o
 qat_c62xvf-objs := adf_drv.o adf_c62xvf_hw_data.o

drivers/crypto/intel/qat/qat_dh895xcc/Makefile

 # SPDX-License-Identifier: GPL-2.0-only
-ccflags-y := -I $(srctree)/$(src)/../qat_common
+ccflags-y := -I $(src)/../qat_common
 obj-$(CONFIG_CRYPTO_DEV_QAT_DH895xCC) += qat_dh895xcc.o
 qat_dh895xcc-objs := adf_drv.o adf_dh895xcc_hw_data.o

drivers/crypto/intel/qat/qat_dh895xccvf/Makefile

 # SPDX-License-Identifier: GPL-2.0-only
-ccflags-y := -I $(srctree)/$(src)/../qat_common
+ccflags-y := -I $(src)/../qat_common
 obj-$(CONFIG_CRYPTO_DEV_QAT_DH895xCCVF) += qat_dh895xccvf.o
 qat_dh895xccvf-objs := adf_drv.o adf_dh895xccvf_hw_data.o

drivers/gpu/drm/amd/amdgpu/Makefile

@@ -23,7 +23,7 @@
 # Makefile for the drm device driver.  This driver provides support for the
 # Direct Rendering Infrastructure (DRI) in XFree86 4.1.0 and higher.
 
-FULL_AMD_PATH=$(srctree)/$(src)/..
+FULL_AMD_PATH=$(src)/..
 DISPLAY_FOLDER_NAME=display
 FULL_AMD_DISPLAY_PATH = $(FULL_AMD_PATH)/$(DISPLAY_FOLDER_NAME)
 

drivers/gpu/drm/arm/display/komeda/Makefile

 # SPDX-License-Identifier: GPL-2.0
 
 ccflags-y := \
-	-I $(srctree)/$(src)/../include \
-	-I $(srctree)/$(src)
+	-I $(src)/../include \
+	-I $(src)
 
 komeda-y := \
 	komeda_drv.o \

drivers/gpu/drm/i915/Makefile

@@ -41,7 +41,7 @@ CFLAGS_display/intel_fbdev.o = -Wno-override-init
 # drivers. Define I915 when building i915.
 subdir-ccflags-y += -DI915
 
-subdir-ccflags-y += -I$(srctree)/$(src)
+subdir-ccflags-y += -I$(src)
 
 # Please keep these build lists sorted!
 
@@ -434,7 +434,7 @@ no-header-test := \
 
 always-$(CONFIG_DRM_I915_WERROR) += \
 	$(patsubst %.h,%.hdrtest, $(filter-out $(no-header-test), \
-		$(shell cd $(srctree)/$(src) && find * -name '*.h')))
+		$(shell cd $(src) && find * -name '*.h')))
 
 quiet_cmd_hdrtest = HDRTEST $(patsubst %.hdrtest,%.h,$@)
       cmd_hdrtest = $(CC) $(filter-out $(CFLAGS_GCOV), $(c_flags)) -S -o /dev/null -x c /dev/null -include $<; \

drivers/gpu/drm/imagination/Makefile

 # SPDX-License-Identifier: GPL-2.0-only OR MIT
 # Copyright (c) 2023 Imagination Technologies Ltd.
 
-subdir-ccflags-y := -I$(srctree)/$(src)
+subdir-ccflags-y := -I$(src)
 
 powervr-y := \
 	pvr_ccb.o \

drivers/gpu/drm/msm/Makefile

 # SPDX-License-Identifier: GPL-2.0
-ccflags-y := -I $(srctree)/$(src)
-ccflags-y += -I $(srctree)/$(src)/disp/dpu1
-ccflags-$(CONFIG_DRM_MSM_DSI) += -I $(srctree)/$(src)/dsi
-ccflags-$(CONFIG_DRM_MSM_DP) += -I $(srctree)/$(src)/dp
+ccflags-y := -I $(src)
+ccflags-y += -I $(src)/disp/dpu1
+ccflags-$(CONFIG_DRM_MSM_DSI) += -I $(src)/dsi
+ccflags-$(CONFIG_DRM_MSM_DP) += -I $(src)/dp
 
 msm-y := \
 	adreno/adreno_device.o \

drivers/gpu/drm/nouveau/Kbuild

-NOUVEAU_PATH ?= $(srctree)
-
 # SPDX-License-Identifier: MIT
-ccflags-y += -I $(NOUVEAU_PATH)/$(src)/include
-ccflags-y += -I $(NOUVEAU_PATH)/$(src)/include/nvkm
-ccflags-y += -I $(NOUVEAU_PATH)/$(src)/nvkm
-ccflags-y += -I $(NOUVEAU_PATH)/$(src)
+ccflags-y += -I $(src)/include
+ccflags-y += -I $(src)/include/nvkm
+ccflags-y += -I $(src)/nvkm
+ccflags-y += -I $(src)
 
 # NVKM - HW resource manager
 #- code also used by various userspace tools/tests

drivers/gpu/drm/xe/Makefile

@@ -32,7 +32,7 @@ endif
 # Enable -Werror in CI and development
 subdir-ccflags-$(CONFIG_DRM_XE_WERROR) += -Werror
 
-subdir-ccflags-y += -I$(obj) -I$(srctree)/$(src)
+subdir-ccflags-y += -I$(obj) -I$(src)
 
 # generated sources
 hostprogs := xe_gen_wa_oob
@@ -43,7 +43,7 @@ quiet_cmd_wa_oob = GEN     $(notdir $(generated_oob))
       cmd_wa_oob = mkdir -p $(@D); $^ $(generated_oob)
 
 $(obj)/generated/%_wa_oob.c $(obj)/generated/%_wa_oob.h: $(obj)/xe_gen_wa_oob \
-		 $(srctree)/$(src)/xe_wa_oob.rules
+		 $(src)/xe_wa_oob.rules
 	$(call cmd,wa_oob)
 
 uses_generated_oob := \
@@ -166,8 +166,8 @@ endif
 
 # i915 Display compat #defines and #includes
 subdir-ccflags-$(CONFIG_DRM_XE_DISPLAY) += \
-	-I$(srctree)/$(src)/display/ext \
-	-I$(srctree)/$(src)/compat-i915-headers \
+	-I$(src)/display/ext \
+	-I$(src)/compat-i915-headers \
 	-I$(srctree)/drivers/gpu/drm/i915/display/ \
 	-Ddrm_i915_gem_object=xe_bo \
 	-Ddrm_i915_private=xe_device
@@ -310,7 +310,7 @@ ifneq ($(CONFIG_DRM_XE_DISPLAY),y)
 endif
 
 always-$(CONFIG_DRM_XE_WERROR) += \
-	$(patsubst %.h,%.hdrtest, $(shell cd $(srctree)/$(src) && find * -name '*.h' $(hdrtest_find_args)))
+	$(patsubst %.h,%.hdrtest, $(shell cd $(src) && find * -name '*.h' $(hdrtest_find_args)))
 
 quiet_cmd_hdrtest = HDRTEST $(patsubst %.hdrtest,%.h,$@)
       cmd_hdrtest = $(CC) -DHDRTEST $(filter-out $(CFLAGS_GCOV), $(c_flags)) -S -o /dev/null -x c /dev/null -include $<; touch $@

drivers/hid/amd-sfh-hid/Makefile

@@ -13,4 +13,4 @@ amd_sfh-objs += sfh1_1/amd_sfh_init.o
 amd_sfh-objs += sfh1_1/amd_sfh_interface.o
 amd_sfh-objs += sfh1_1/amd_sfh_desc.o
 
-ccflags-y += -I $(srctree)/$(src)/
+ccflags-y += -I $(src)/

drivers/hid/intel-ish-hid/Makefile

@@ -23,4 +23,4 @@ intel-ishtp-hid-objs += ishtp-hid-client.o
 obj-$(CONFIG_INTEL_ISH_FIRMWARE_DOWNLOADER) += intel-ishtp-loader.o
 intel-ishtp-loader-objs += ishtp-fw-loader.o
 
-ccflags-y += -I $(srctree)/$(src)/ishtp
+ccflags-y += -I $(src)/ishtp

drivers/md/dm-vdo/Makefile

 # SPDX-License-Identifier: GPL-2.0-only
 
-ccflags-y := -I$(srctree)/$(src) -I$(srctree)/$(src)/indexer
+ccflags-y := -I$(src) -I$(src)/indexer
 
 obj-$(CONFIG_DM_VDO) += dm-vdo.o
 

drivers/net/ethernet/aquantia/atlantic/Makefile

@@ -8,7 +8,7 @@
 
 obj-$(CONFIG_AQTION) += atlantic.o
 
-ccflags-y += -I$(srctree)/$(src)
+ccflags-y += -I$(src)
 
 atlantic-objs := aq_main.o \
 	aq_nic.o \

drivers/net/ethernet/chelsio/libcxgb/Makefile

 # SPDX-License-Identifier: GPL-2.0-only
-ccflags-y := -I $(srctree)/$(src)/../cxgb4
+ccflags-y := -I $(src)/../cxgb4
 
 obj-$(CONFIG_CHELSIO_LIB) += libcxgb.o
 

drivers/net/ethernet/fungible/funeth/Makefile

 # SPDX-License-Identifier: (GPL-2.0-only OR BSD-3-Clause)
 
-ccflags-y += -I$(srctree)/$(src)/../funcore -I$(srctree)/$(src)
+ccflags-y += -I$(src)/../funcore -I$(src)
 
 obj-$(CONFIG_FUN_ETH) += funeth.o
 

drivers/net/ethernet/hisilicon/hns3/Makefile

@@ -3,7 +3,7 @@
 # Makefile for the HISILICON network device drivers.
 #
 
-ccflags-y += -I$(srctree)/$(src)
+ccflags-y += -I$(src)
 ccflags-y += -I$(srctree)/drivers/net/ethernet/hisilicon/hns3/hns3pf
 ccflags-y += -I$(srctree)/drivers/net/ethernet/hisilicon/hns3/hns3vf
 ccflags-y += -I$(srctree)/drivers/net/ethernet/hisilicon/hns3/hns3_common

drivers/net/wireless/broadcom/brcm80211/brcmfmac/Makefile

@@ -6,8 +6,8 @@
 #
 
 ccflags-y += \
-	-I $(srctree)/$(src) \
-	-I $(srctree)/$(src)/../include
+	-I $(src) \
+	-I $(src)/../include
 
 obj-$(CONFIG_BRCMFMAC) += brcmfmac.o
 brcmfmac-objs += \

drivers/net/wireless/broadcom/brcm80211/brcmfmac/bca/Makefile

@@ -3,9 +3,9 @@
 # Copyright (c) 2022 Broadcom Corporation
 
 ccflags-y += \
-	-I $(srctree)/$(src) \
-	-I $(srctree)/$(src)/.. \
-	-I $(srctree)/$(src)/../../include
+	-I $(src) \
+	-I $(src)/.. \
+	-I $(src)/../../include
 
 obj-m += brcmfmac-bca.o
 brcmfmac-bca-objs += \

drivers/net/wireless/broadcom/brcm80211/brcmfmac/cyw/Makefile

@@ -3,9 +3,9 @@
 # Copyright (c) 2022 Broadcom Corporation
 
 ccflags-y += \
-	-I $(srctree)/$(src) \
-	-I $(srctree)/$(src)/.. \
-	-I $(srctree)/$(src)/../../include
+	-I $(src) \
+	-I $(src)/.. \
+	-I $(src)/../../include
 
 obj-m += brcmfmac-cyw.o
 brcmfmac-cyw-objs += \

drivers/net/wireless/broadcom/brcm80211/brcmfmac/wcc/Makefile

@@ -3,9 +3,9 @@
 # Copyright (c) 2022 Broadcom Corporation
 
 ccflags-y += \
-	-I $(srctree)/$(src) \
-	-I $(srctree)/$(src)/.. \
-	-I $(srctree)/$(src)/../../include
+	-I $(src) \
+	-I $(src)/.. \
+	-I $(src)/../../include
 
 obj-m += brcmfmac-wcc.o
 brcmfmac-wcc-objs += \

drivers/net/wireless/broadcom/brcm80211/brcmsmac/Makefile

@@ -16,9 +16,9 @@
 # CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 
 ccflags-y := \
-	-I $(srctree)/$(src) \
-	-I $(srctree)/$(src)/phy \
-	-I $(srctree)/$(src)/../include
+	-I $(src) \
+	-I $(src)/phy \
+	-I $(src)/../include
 
 brcmsmac-y := \
 	mac80211_if.o \

drivers/net/wireless/broadcom/brcm80211/brcmutil/Makefile

@@ -4,7 +4,7 @@
 #
 # Copyright (c) 2011 Broadcom Corporation
 #
-ccflags-y := -I $(srctree)/$(src)/../include
+ccflags-y := -I $(src)/../include
 
 obj-$(CONFIG_BRCMUTIL)	+= brcmutil.o
 brcmutil-objs	= utils.o d11.o

drivers/net/wireless/intel/iwlwifi/dvm/Makefile

@@ -11,4 +11,4 @@ iwldvm-objs		+= rxon.o devices.o
 iwldvm-$(CONFIG_IWLWIFI_LEDS) += led.o
 iwldvm-$(CONFIG_IWLWIFI_DEBUGFS) += debugfs.o
 
-ccflags-y += -I $(srctree)/$(src)/../
+ccflags-y += -I $(src)/../

drivers/net/wireless/intel/iwlwifi/mei/Makefile

@@ -5,4 +5,4 @@ iwlmei-y += net.o
 iwlmei-$(CONFIG_IWLWIFI_DEVICE_TRACING) += trace.o
 CFLAGS_trace.o := -I$(src)
 
-ccflags-y += -I $(srctree)/$(src)/../
+ccflags-y += -I $(src)/../

drivers/net/wireless/intel/iwlwifi/mvm/Makefile

@@ -15,4 +15,4 @@ iwlmvm-$(CONFIG_IWLWIFI_LEDS) += led.o
 iwlmvm-$(CONFIG_PM) += d3.o
 iwlmvm-$(CONFIG_IWLMEI) += vendor-cmd.o
 
-ccflags-y += -I $(srctree)/$(src)/../
+ccflags-y += -I $(src)/../

drivers/net/wireless/intel/iwlwifi/tests/Makefile

@@ -2,6 +2,6 @@
 
 iwlwifi-tests-y += module.o devinfo.o
 
-ccflags-y += -I$(srctree)/$(src)/../
+ccflags-y += -I$(src)/../
 
 obj-$(CONFIG_IWLWIFI_KUNIT_TESTS) += iwlwifi-tests.o

drivers/net/wireless/realtek/rtl818x/rtl8180/Makefile

@@ -3,4 +3,4 @@ rtl818x_pci-objs	:= dev.o rtl8225.o sa2400.o max2820.o grf5101.o rtl8225se.o
 
 obj-$(CONFIG_RTL8180)	+= rtl818x_pci.o
 
-ccflags-y += -I $(srctree)/$(src)/..
+ccflags-y += -I $(src)/..

drivers/net/wireless/realtek/rtl818x/rtl8187/Makefile

@@ -3,4 +3,4 @@ rtl8187-objs		:= dev.o rtl8225.o leds.o rfkill.o
 
 obj-$(CONFIG_RTL8187)	+= rtl8187.o
 
-ccflags-y += -I $(srctree)/$(src)/..
+ccflags-y += -I $(src)/..

drivers/scsi/aic7xxx/Makefile

@@ -55,9 +55,9 @@ aicasm-7xxx-opts-$(CONFIG_AIC7XXX_REG_PRETTY_PRINT) := \
 
 ifeq ($(CONFIG_AIC7XXX_BUILD_FIRMWARE),y)
 $(obj)/aic7xxx_seq.h: $(src)/aic7xxx.seq $(src)/aic7xxx.reg $(obj)/aicasm/aicasm
-	$(obj)/aicasm/aicasm -I$(srctree)/$(src) -r $(obj)/aic7xxx_reg.h \
+	$(obj)/aicasm/aicasm -I $(src) -r $(obj)/aic7xxx_reg.h \
 			      $(aicasm-7xxx-opts-y) -o $(obj)/aic7xxx_seq.h \
-			      $(srctree)/$(src)/aic7xxx.seq
+			      $(src)/aic7xxx.seq
 
 $(aic7xxx-gen-y): $(objtree)/$(obj)/aic7xxx_seq.h
 	@true
@@ -73,9 +73,9 @@ aicasm-79xx-opts-$(CONFIG_AIC79XX_REG_PRETTY_PRINT) := \
 
 ifeq ($(CONFIG_AIC79XX_BUILD_FIRMWARE),y)
 $(obj)/aic79xx_seq.h: $(src)/aic79xx.seq $(src)/aic79xx.reg $(obj)/aicasm/aicasm
-	$(obj)/aicasm/aicasm -I$(srctree)/$(src) -r $(obj)/aic79xx_reg.h \
+	$(obj)/aicasm/aicasm -I $(src) -r $(obj)/aic79xx_reg.h \
 			      $(aicasm-79xx-opts-y) -o $(obj)/aic79xx_seq.h \
-			      $(srctree)/$(src)/aic79xx.seq
+			      $(src)/aic79xx.seq
 
 $(aic79xx-gen-y): $(objtree)/$(obj)/aic79xx_seq.h
 	@true
@@ -83,5 +83,5 @@ else
 $(obj)/aic79xx_reg_print.c: $(src)/aic79xx_reg_print.c_shipped
 endif
 
-$(obj)/aicasm/aicasm: $(srctree)/$(src)/aicasm/*.[chyl]
-	$(MAKE) -C $(srctree)/$(src)/aicasm OUTDIR=$(shell pwd)/$(obj)/aicasm/
+$(obj)/aicasm/aicasm: $(src)/aicasm/*.[chyl]
+	$(MAKE) -C $(src)/aicasm OUTDIR=$(shell pwd)/$(obj)/aicasm/

drivers/staging/rtl8723bs/Makefile

@@ -62,4 +62,4 @@ r8723bs-y = \
 
 obj-$(CONFIG_RTL8723BS) := r8723bs.o
 
-ccflags-y += -I$(srctree)/$(src)/include -I$(srctree)/$(src)/hal
+ccflags-y += -I$(src)/include -I$(src)/hal

fs/iomap/Makefile

@@ -4,7 +4,7 @@
 # All Rights Reserved.
 #
 
-ccflags-y += -I $(srctree)/$(src)		# needed for trace events
+ccflags-y += -I $(src)		# needed for trace events
 
 obj-$(CONFIG_FS_IOMAP)		+= iomap.o
 

fs/unicode/Makefile

@@ -18,13 +18,13 @@ ifdef REGENERATE_UTF8DATA
 
 quiet_cmd_utf8data = GEN     $@
       cmd_utf8data = $< \
-		-a $(srctree)/$(src)/DerivedAge.txt \
-		-c $(srctree)/$(src)/DerivedCombiningClass.txt \
-		-p $(srctree)/$(src)/DerivedCoreProperties.txt \
-		-d $(srctree)/$(src)/UnicodeData.txt \
-		-f $(srctree)/$(src)/CaseFolding.txt \
-		-n $(srctree)/$(src)/NormalizationCorrections.txt \
-		-t $(srctree)/$(src)/NormalizationTest.txt \
+		-a $(src)/DerivedAge.txt \
+		-c $(src)/DerivedCombiningClass.txt \
+		-p $(src)/DerivedCoreProperties.txt \
+		-d $(src)/UnicodeData.txt \
+		-f $(src)/CaseFolding.txt \
+		-n $(src)/NormalizationCorrections.txt \
+		-t $(src)/NormalizationTest.txt \
 		-o $@
 
 $(obj)/utf8data.c: $(obj)/mkutf8data $(filter %.txt, $(cmd_utf8data)) FORCE

fs/xfs/Makefile

@@ -4,8 +4,8 @@
 # All Rights Reserved.
 #
 
-ccflags-y += -I $(srctree)/$(src)		# needed for trace events
-ccflags-y += -I $(srctree)/$(src)/libxfs
+ccflags-y += -I $(src)		# needed for trace events
+ccflags-y += -I $(src)/libxfs
 
 obj-$(CONFIG_XFS_FS)		+= xfs.o
 

init/Makefile

@@ -52,7 +52,7 @@ CFLAGS_version.o := -include $(obj)/utsversion-tmp.h
 # Build version-timestamp.c with final UTS_VERSION
 #
 
-include/generated/utsversion.h: build-version-auto = $(shell $(srctree)/$(src)/build-version)
+include/generated/utsversion.h: build-version-auto = $(shell $(src)/build-version)
 include/generated/utsversion.h: build-timestamp-auto = $(shell LC_ALL=C date)
 include/generated/utsversion.h: FORCE
 	$(call filechk,uts_version)

lib/Makefile

@@ -352,7 +352,7 @@ $(obj)/oid_registry_data.c: $(srctree)/include/linux/oid_registry.h \
 	$(call cmd,build_OID_registry)
 
 quiet_cmd_build_OID_registry = GEN     $@
-      cmd_build_OID_registry = perl $(srctree)/$(src)/build_OID_registry $< $@
+      cmd_build_OID_registry = perl $(src)/build_OID_registry $< $@
 
 clean-files	+= oid_registry_data.c
 
@@ -412,8 +412,8 @@ obj-$(CONFIG_GENERIC_LIB_DEVMEM_IS_ALLOWED) += devmem_is_allowed.o
 obj-$(CONFIG_FIRMWARE_TABLE) += fw_table.o
 
 # FORTIFY_SOURCE compile-time behavior tests
-TEST_FORTIFY_SRCS = $(wildcard $(srctree)/$(src)/test_fortify/*-*.c)
-TEST_FORTIFY_LOGS = $(patsubst $(srctree)/$(src)/%.c, %.log, $(TEST_FORTIFY_SRCS))
+TEST_FORTIFY_SRCS = $(wildcard $(src)/test_fortify/*-*.c)
+TEST_FORTIFY_LOGS = $(patsubst $(src)/%.c, %.log, $(TEST_FORTIFY_SRCS))
 TEST_FORTIFY_LOG = test_fortify.log
 
 quiet_cmd_test_fortify = TEST    $@

lib/raid6/Makefile

@@ -53,7 +53,7 @@ endif
 endif
 
 quiet_cmd_unroll = UNROLL  $@
-      cmd_unroll = $(AWK) -v N=$* -f $(srctree)/$(src)/unroll.awk < $< > $@
+      cmd_unroll = $(AWK) -v N=$* -f $(src)/unroll.awk < $< > $@
 
 targets += int1.c int2.c int4.c int8.c
 $(obj)/int%.c: $(src)/int.uc $(src)/unroll.awk FORCE

net/wireless/Makefile

@@ -25,7 +25,7 @@ ifneq ($(CONFIG_CFG80211_EXTRA_REGDB_KEYDIR),)
 cfg80211-y += extra-certs.o
 endif
 
-$(obj)/shipped-certs.c: $(sort $(wildcard $(srctree)/$(src)/certs/*.hex))
+$(obj)/shipped-certs.c: $(sort $(wildcard $(src)/certs/*.hex))
 	@$(kecho) "  GEN     $@"
 	$(Q)(echo '#include "reg.h"'; \
 	  echo 'const u8 shipped_regdb_certs[] = {'; \

rust/Makefile

@@ -239,7 +239,7 @@ quiet_cmd_rustsysroot = RUSTSYSROOT
 	rm -rf $(objtree)/$(obj)/test; \
 	mkdir -p $(objtree)/$(obj)/test; \
 	cp -a $(rustc_sysroot) $(objtree)/$(obj)/test/sysroot; \
-	cp -r $(srctree)/$(src)/alloc/* \
+	cp -r $(src)/alloc/* \
 		$(objtree)/$(obj)/test/sysroot/lib/rustlib/src/rust/library/alloc/src; \
 	echo '\#!/bin/sh' > $(objtree)/$(obj)/test/rustc_sysroot; \
 	echo "$(RUSTC) --sysroot=$(abspath $(objtree)/$(obj)/test/sysroot) \"\$$@\"" \
@@ -340,7 +340,7 @@ quiet_cmd_bindgen = BINDGEN $@
 		$(bindgen_target_cflags) $(bindgen_target_extra)
 
 $(obj)/bindings/bindings_generated.rs: private bindgen_target_flags = \
-    $(shell grep -Ev '^#|^$$' $(srctree)/$(src)/bindgen_parameters)
+    $(shell grep -Ev '^#|^$$' $(src)/bindgen_parameters)
 $(obj)/bindings/bindings_generated.rs: private bindgen_target_extra = ; \
     sed -Ei 's/pub const RUST_CONST_HELPER_([a-zA-Z0-9_]*)/pub const \1/g' $@
 $(obj)/bindings/bindings_generated.rs: $(src)/bindings/bindings_helper.h \
@@ -348,7 +348,7 @@ $(obj)/bindings/bindings_generated.rs: $(src)/bindings/bindings_helper.h \
 	$(call if_changed_dep,bindgen)
 
 $(obj)/uapi/uapi_generated.rs: private bindgen_target_flags = \
-    $(shell grep -Ev '^#|^$$' $(srctree)/$(src)/bindgen_parameters)
+    $(shell grep -Ev '^#|^$$' $(src)/bindgen_parameters)
 $(obj)/uapi/uapi_generated.rs: $(src)/uapi/uapi_helper.h \
     $(src)/bindgen_parameters FORCE
 	$(call if_changed_dep,bindgen)

samples/bpf/Makefile

 # SPDX-License-Identifier: GPL-2.0
 
-BPF_SAMPLES_PATH ?= $(abspath $(srctree)/$(src))
+BPF_SAMPLES_PATH ?= $(abspath $(src))
 TOOLS_PATH := $(BPF_SAMPLES_PATH)/../../tools
 
 pound := \#

samples/hid/Makefile

 # SPDX-License-Identifier: GPL-2.0
 
-HID_SAMPLES_PATH ?= $(abspath $(srctree)/$(src))
+HID_SAMPLES_PATH ?= $(abspath $(src))
 TOOLS_PATH := $(HID_SAMPLES_PATH)/../../tools
 
 pound := \#

scripts/Kbuild.include

@@ -62,8 +62,7 @@ stringify = $(squote)$(quote)$1$(quote)$(squote)
 
 ###
 # The path to Kbuild or Makefile. Kbuild has precedence over Makefile.
-kbuild-dir = $(if $(filter /%,$(src)),$(src),$(srctree)/$(src))
-kbuild-file = $(or $(wildcard $(kbuild-dir)/Kbuild),$(kbuild-dir)/Makefile)
+kbuild-file = $(or $(wildcard $(src)/Kbuild),$(src)/Makefile)
 
 ###
 # Read a file, replacing newlines with spaces

scripts/Makefile.asm-generic

@@ -9,7 +9,7 @@
 PHONY := all
 all:
 
-src := $(subst /generated,,$(obj))
+src := $(srctree)/$(subst /generated,,$(obj))
 
 include $(srctree)/scripts/Kbuild.include
 -include $(kbuild-file)
@@ -20,14 +20,14 @@ include $(srctree)/$(generic)/Kbuild
 endif
 
 redundant := $(filter $(mandatory-y) $(generated-y), $(generic-y))
-redundant += $(foreach f, $(generic-y), $(if $(wildcard $(srctree)/$(src)/$(f)),$(f)))
+redundant += $(foreach f, $(generic-y), $(if $(wildcard $(src)/$(f)),$(f)))
 redundant := $(sort $(redundant))
 $(if $(redundant),\
 	$(warning redundant generic-y found in $(src)/Kbuild: $(redundant)))
 
 # If arch does not implement mandatory headers, fallback to asm-generic ones.
 mandatory-y := $(filter-out $(generated-y), $(mandatory-y))
-generic-y   += $(foreach f, $(mandatory-y), $(if $(wildcard $(srctree)/$(src)/$(f)),,$(f)))
+generic-y   += $(foreach f, $(mandatory-y), $(if $(wildcard $(src)/$(f)),,$(f)))
 
 generic-y   := $(addprefix $(obj)/, $(generic-y))
 generated-y := $(addprefix $(obj)/, $(generated-y))

scripts/Makefile.build

@@ -3,7 +3,7 @@
 # Building
 # ==========================================================================
 
-src := $(obj)
+src := $(if $(VPATH),$(VPATH)/)$(obj)
 
 PHONY := $(obj)/
 $(obj)/:

scripts/Makefile.clean

@@ -3,7 +3,7 @@
 # Cleaning up
 # ==========================================================================
 
-src := $(obj)
+src := $(if $(VPATH),$(VPATH)/)$(obj)
 
 PHONY := __clean
 __clean:

scripts/Makefile.lib

@@ -209,13 +209,13 @@ _c_flags += $(if $(patsubst n%,, \
 	-D__KCSAN_INSTRUMENT_BARRIERS__)
 endif
 
-# $(srctree)/$(src) for including checkin headers from generated source files
-# $(objtree)/$(obj) for including generated headers from checkin source files
+# $(src) for including checkin headers from generated source files
+# $(obj) for including generated headers from checkin source files
 ifeq ($(KBUILD_EXTMOD),)
 ifdef building_out_of_srctree
-_c_flags   += $(addprefix -I $(srctree)/,$(src)) $(addprefix -I $(objtree)/,$(obj))
-_a_flags   += $(addprefix -I $(srctree)/,$(src)) $(addprefix -I $(objtree)/,$(obj))
-_cpp_flags += $(addprefix -I $(srctree)/,$(src)) $(addprefix -I $(objtree)/,$(obj))
+_c_flags   += $(addprefix -I, $(src) $(obj))
+_a_flags   += $(addprefix -I, $(src) $(obj))
+_cpp_flags += $(addprefix -I, $(src) $(obj))
 endif
 endif
 

scripts/Makefile.modpost

@@ -112,7 +112,7 @@ else
 
 # set src + obj - they may be used in the modules's Makefile
 obj := $(KBUILD_EXTMOD)
-src := $(obj)
+src := $(if $(VPATH),$(VPATH)/)$(obj)
 
 # Include the module's Makefile to find KBUILD_EXTRA_SYMBOLS
 include $(kbuild-file)

scripts/dtc/Makefile

@@ -16,12 +16,12 @@ libfdt		= $(addprefix libfdt/,$(libfdt-objs))
 fdtoverlay-objs	:= $(libfdt) fdtoverlay.o util.o
 
 # Source files need to get at the userspace version of libfdt_env.h to compile
-HOST_EXTRACFLAGS += -I $(srctree)/$(src)/libfdt
+HOST_EXTRACFLAGS += -I $(src)/libfdt
 HOST_EXTRACFLAGS += -DNO_YAML
 
 # Generated files need one more search path to include headers in source tree
-HOSTCFLAGS_dtc-lexer.lex.o := -I $(srctree)/$(src)
-HOSTCFLAGS_dtc-parser.tab.o := -I $(srctree)/$(src)
+HOSTCFLAGS_dtc-lexer.lex.o := -I $(src)
+HOSTCFLAGS_dtc-parser.tab.o := -I $(src)
 
 # dependencies on generated files need to be listed explicitly
 $(obj)/dtc-lexer.lex.o: $(obj)/dtc-parser.tab.h

scripts/gdb/linux/Makefile

@@ -2,7 +2,7 @@
 
 ifdef building_out_of_srctree
 
-symlinks := $(patsubst $(srctree)/$(src)/%,%,$(wildcard $(srctree)/$(src)/*.py))
+symlinks := $(patsubst $(src)/%,%,$(wildcard $(src)/*.py))
 
 quiet_cmd_symlink = SYMLINK $@
       cmd_symlink = ln -fsn $(patsubst $(obj)/%,$(abspath $(srctree))/$(src)/%,$@) $@

scripts/genksyms/Makefile

@@ -23,8 +23,8 @@ $(obj)/pars%.tab.c $(obj)/pars%.tab.h: $(src)/pars%.y FORCE
 endif
 
 # -I needed for generated C source to include headers in source tree
-HOSTCFLAGS_parse.tab.o := -I $(srctree)/$(src)
-HOSTCFLAGS_lex.lex.o := -I $(srctree)/$(src)
+HOSTCFLAGS_parse.tab.o := -I $(src)
+HOSTCFLAGS_lex.lex.o := -I $(src)
 
 # dependencies on generated files need to be listed explicitly
 $(obj)/lex.lex.o: $(obj)/parse.tab.h

scripts/kconfig/Makefile

@@ -57,7 +57,7 @@ $(foreach c, config menuconfig nconfig gconfig xconfig, $(eval $(call config_rul
 
 PHONY += localmodconfig localyesconfig
 localyesconfig localmodconfig: $(obj)/conf
-	$(Q)$(PERL) $(srctree)/$(src)/streamline_config.pl --$@ $(srctree) $(Kconfig) > .tmp.config
+	$(Q)$(PERL) $(src)/streamline_config.pl --$@ $(srctree) $(Kconfig) > .tmp.config
 	$(Q)if [ -f .config ]; then 				\
 		cmp -s .tmp.config .config ||			\
 		(mv -f .config .config.old.1;			\
@@ -118,7 +118,7 @@ tinyconfig:
 # CHECK: -o cache_dir=<path> working?
 PHONY += testconfig
 testconfig: $(obj)/conf
-	$(Q)$(PYTHON3) -B -m pytest $(srctree)/$(src)/tests \
+	$(Q)$(PYTHON3) -B -m pytest $(src)/tests \
 	-o cache_dir=$(abspath $(obj)/tests/.cache) \
 	$(if $(findstring 1,$(KBUILD_VERBOSE)),--capture=no)
 clean-files += tests/.cache
@@ -165,8 +165,8 @@ common-objs	:= confdata.o expr.o lexer.lex.o menu.o parser.tab.o \
 		   preprocess.o symbol.o util.o
 
 $(obj)/lexer.lex.o: $(obj)/parser.tab.h
-HOSTCFLAGS_lexer.lex.o	:= -I $(srctree)/$(src)
-HOSTCFLAGS_parser.tab.o	:= -I $(srctree)/$(src)
+HOSTCFLAGS_lexer.lex.o	:= -I $(src)
+HOSTCFLAGS_parser.tab.o	:= -I $(src)
 
 # conf: Used for defconfig, oldconfig and related targets
 hostprogs	+= conf

security/tomoyo/Makefile

@@ -11,7 +11,7 @@ quiet_cmd_policy = POLICY  $@
 	printf '\t"";\n';) \
 	} > $@
 
-$(obj)/builtin-policy.h: $(wildcard $(obj)/policy/*.conf $(srctree)/$(src)/policy/*.conf.default) FORCE
+$(obj)/builtin-policy.h: $(wildcard $(obj)/policy/*.conf $(src)/policy/*.conf.default) FORCE
 	$(call if_changed,policy)
 
 ifndef CONFIG_SECURITY_TOMOYO_INSECURE_BUILTIN_SETTING

usr/Makefile

@@ -22,7 +22,7 @@ cpio-data :=
 # If CONFIG_INITRAMFS_SOURCE is empty, generate a small initramfs with the
 # default contents.
 ifeq ($(ramfs-input),)
-ramfs-input := $(srctree)/$(src)/default_cpio_list
+ramfs-input := $(src)/default_cpio_list
 endif
 
 ifeq ($(words $(ramfs-input)),1)

usr/include/Makefile

@@ -78,7 +78,7 @@ quiet_cmd_hdrtest = HDRTEST $<
       cmd_hdrtest = \
 		$(CC) $(c_flags) -fsyntax-only -x c /dev/null \
 			$(if $(filter-out $(no-header-test), $*.h), -include $< -include $<); \
-		$(PERL) $(srctree)/$(src)/headers_check.pl $(obj) $(SRCARCH) $<; \
+		$(PERL) $(src)/headers_check.pl $(obj) $(SRCARCH) $<; \
 		touch $@
 
 $(obj)/%.hdrtest: $(obj)/%.h FORCE