Makefile

# when using lld < 13.0.0.
ifneq ($(CONFIG_FRAME_WARN),0)
ifeq ($(call test-lt, $(CONFIG_LLD_VERSION), 130000),y)
KBUILD_LDFLAGS	+= -plugin-opt=-warn-stack-size=$(CONFIG_FRAME_WARN)
endif
endif
endif

ifdef CONFIG_LTO
KBUILD_CFLAGS	+= -fno-lto $(CC_FLAGS_LTO)
KBUILD_AFLAGS	+= -fno-lto
export CC_FLAGS_LTO
endif

ifdef CONFIG_CFI_CLANG
CC_FLAGS_CFI	:= -fsanitize=kcfi
KBUILD_CFLAGS	+= $(CC_FLAGS_CFI)
export CC_FLAGS_CFI
endif

ifneq ($(CONFIG_FUNCTION_ALIGNMENT),0)
KBUILD_CFLAGS += -falign-functions=$(CONFIG_FUNCTION_ALIGNMENT)
endif

# arch Makefile may override CC so keep this after arch Makefile is included
NOSTDINC_FLAGS += -nostdinc

# Variable Length Arrays (VLAs) should not be used anywhere in the kernel
KBUILD_CFLAGS += -Wvla

# disable pointer signed / unsigned warnings in gcc 4.0
KBUILD_CFLAGS += -Wno-pointer-sign

# In order to make sure new function cast mismatches are not introduced
# in the kernel (to avoid tripping CFI checking), the kernel should be
# globally built with -Wcast-function-type.
KBUILD_CFLAGS += $(call cc-option, -Wcast-function-type)

# To gain proper coverage for CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE,
# the kernel uses only C99 flexible arrays for dynamically sized trailing
# arrays. Enforce this for everything that may examine structure sizes and
# perform bounds checking.
KBUILD_CFLAGS += $(call cc-option, -fstrict-flex-arrays=3)

# disable stringop warnings in gcc 8+
KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)

# We'll want to enable this eventually, but it's not going away for 5.7 at least
KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)

# Another good warning that we'll want to enable eventually
KBUILD_CFLAGS += $(call cc-disable-warning, restrict)

# Enabled with W=2, disabled by default as noisy
ifdef CONFIG_CC_IS_GCC
KBUILD_CFLAGS += -Wno-maybe-uninitialized
endif

# The allocators already balk at large sizes, so silence the compiler
# warnings for bounds checks involving those possible values. While
# -Wno-alloc-size-larger-than would normally be used here, earlier versions
# of gcc (<9.1) weirdly don't handle the option correctly when _other_
# warnings are produced (?!). Using -Walloc-size-larger-than=SIZE_MAX
# doesn't work (as it is documented to), silently resolving to "0" prior to
# version 9.1 (and producing an error more recently). Numeric values larger
# than PTRDIFF_MAX also don't work prior to version 9.1, which are silently
# ignored, continuing to default to PTRDIFF_MAX. So, left with no other
# choice, we must perform a versioned check to disable this warning.
# https://lore.kernel.org/lkml/20210824115859.187f272f@canb.auug.org.au
KBUILD_CFLAGS-$(call gcc-min-version, 90100) += -Wno-alloc-size-larger-than
KBUILD_CFLAGS += $(KBUILD_CFLAGS-y) $(CONFIG_CC_IMPLICIT_FALLTHROUGH)

# disable invalid "can't wrap" optimizations for signed / pointers
KBUILD_CFLAGS	+= -fno-strict-overflow

# Make sure -fstack-check isn't enabled (like gentoo apparently did)
KBUILD_CFLAGS  += -fno-stack-check

# conserve stack if available
ifdef CONFIG_CC_IS_GCC
KBUILD_CFLAGS   += -fconserve-stack
endif

# Prohibit date/time macros, which would make the build non-deterministic
KBUILD_CFLAGS   += -Werror=date-time

# enforce correct pointer usage
KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)

# Require designated initializers for all marked structures
KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)

# change __FILE__ to the relative path from the srctree
KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)

# include additional Makefiles when needed
include-y			:= scripts/Makefile.extrawarn
include-$(CONFIG_DEBUG_INFO)	+= scripts/Makefile.debug
include-$(CONFIG_KASAN)		+= scripts/Makefile.kasan
include-$(CONFIG_KCSAN)		+= scripts/Makefile.kcsan
include-$(CONFIG_KMSAN)		+= scripts/Makefile.kmsan
include-$(CONFIG_UBSAN)		+= scripts/Makefile.ubsan
include-$(CONFIG_KCOV)		+= scripts/Makefile.kcov
include-$(CONFIG_RANDSTRUCT)	+= scripts/Makefile.randstruct
include-$(CONFIG_GCC_PLUGINS)	+= scripts/Makefile.gcc-plugins

include $(addprefix $(srctree)/, $(include-y))

# scripts/Makefile.gcc-plugins is intentionally included last.
# Do not add $(call cc-option,...) below this line. When you build the kernel
# from the clean source tree, the GCC plugins do not exist at this point.

# Add user supplied CPPFLAGS, AFLAGS, CFLAGS and RUSTFLAGS as the last assignments
KBUILD_CPPFLAGS += $(KCPPFLAGS)
KBUILD_AFLAGS   += $(KAFLAGS)
KBUILD_CFLAGS   += $(KCFLAGS)
KBUILD_RUSTFLAGS += $(KRUSTFLAGS)

KBUILD_LDFLAGS_MODULE += --build-id=sha1
LDFLAGS_vmlinux += --build-id=sha1

KBUILD_LDFLAGS	+= -z noexecstack
ifeq ($(CONFIG_LD_IS_BFD),y)
KBUILD_LDFLAGS	+= $(call ld-option,--no-warn-rwx-segments)
endif

ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
LDFLAGS_vmlinux	+= -X
endif

ifeq ($(CONFIG_RELR),y)
# ld.lld before 15 did not support -z pack-relative-relocs.
LDFLAGS_vmlinux	+= $(call ld-option,--pack-dyn-relocs=relr,-z pack-relative-relocs)
endif

# We never want expected sections to be placed heuristically by the
# linker. All sections should be explicitly named in the linker script.
ifdef CONFIG_LD_ORPHAN_WARN
LDFLAGS_vmlinux += --orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL)
endif

# Align the bit size of userspace programs with the kernel
KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))

# make the checker run with the right architecture
CHECKFLAGS += --arch=$(ARCH)

# insure the checker run with the right endianness
CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)

# the checker needs the correct machine size
CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)

# Default kernel image to build when no specific target is given.
# KBUILD_IMAGE may be overruled on the command line or
# set in the environment
# Also any assignments in arch/$(ARCH)/Makefile take precedence over
# this default value
export KBUILD_IMAGE ?= vmlinux

#
# INSTALL_PATH specifies where to place the updated kernel and system map
# images. Default is /boot, but you can set it to other values
export	INSTALL_PATH ?= /boot

#
# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
# an argument if needed. Otherwise it defaults to the kernel install path
#
export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)

#
# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
# relocations required by build roots.  This is not defined in the
# makefile but the argument can be passed to make if needed.
#

MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
export MODLIB

PHONY += prepare0

export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
export MODORDER := $(extmod_prefix)modules.order
export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps

ifeq ($(KBUILD_EXTMOD),)

build-dir	:= .
clean-dirs	:= $(sort . Documentation \
		     $(patsubst %/,%,$(filter %/, $(core-) \
			$(drivers-) $(libs-))))

export ARCH_CORE	:= $(core-y)
export ARCH_LIB		:= $(filter %/, $(libs-y))
export ARCH_DRIVERS	:= $(drivers-y) $(drivers-m)
# Externally visible symbols (used by link-vmlinux.sh)

KBUILD_VMLINUX_OBJS := ./built-in.a
ifdef CONFIG_MODULES
KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
else
KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
endif

export KBUILD_VMLINUX_LIBS
export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds

ifdef CONFIG_TRIM_UNUSED_KSYMS
# For the kernel to actually contain only the needed exported symbols,
# we have to build modules as well to determine what those symbols are.
KBUILD_MODULES := 1
endif

# '$(AR) mPi' needs 'T' to workaround the bug of llvm-ar <= 14
quiet_cmd_ar_vmlinux.a = AR      $@
      cmd_ar_vmlinux.a = \
	rm -f $@; \
	$(AR) cDPrST $@ $(KBUILD_VMLINUX_OBJS); \
	$(AR) mPiT $$($(AR) t $@ | sed -n 1p) $@ $$($(AR) t $@ | grep -F -f $(srctree)/scripts/head-object-list.txt)

targets += vmlinux.a
vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt FORCE
	$(call if_changed,ar_vmlinux.a)

PHONY += vmlinux_o
vmlinux_o: vmlinux.a $(KBUILD_VMLINUX_LIBS)
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o

vmlinux.o modules.builtin.modinfo modules.builtin: vmlinux_o
	@:

PHONY += vmlinux
# LDFLAGS_vmlinux in the top Makefile defines linker flags for the top vmlinux,
# not for decompressors. LDFLAGS_vmlinux in arch/*/boot/compressed/Makefile is
# unrelated; the decompressors just happen to have the same base name,
# arch/*/boot/compressed/vmlinux.
# Export LDFLAGS_vmlinux only to scripts/Makefile.vmlinux.
#
# _LDFLAGS_vmlinux is a workaround for the 'private export' bug:
#   https://savannah.gnu.org/bugs/?61463
# For Make > 4.4, the following simple code will work:
#  vmlinux: private export LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
vmlinux: private _LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
vmlinux: export LDFLAGS_vmlinux = $(_LDFLAGS_vmlinux)
vmlinux: vmlinux.o $(KBUILD_LDS) modpost
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux

# The actual objects are generated when descending,
# make sure no implicit rule kicks in
$(sort $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)): . ;

ifeq ($(origin KERNELRELEASE),file)
filechk_kernel.release = $(srctree)/scripts/setlocalversion $(srctree)
else
filechk_kernel.release = echo $(KERNELRELEASE)
endif

# Store (new) KERNELRELEASE string in include/config/kernel.release
include/config/kernel.release: FORCE
	$(call filechk,kernel.release)

# Additional helpers built in scripts/
# Carefully list dependencies so we do not try to build scripts twice
# in parallel
PHONY += scripts
scripts: scripts_basic scripts_dtc
	$(Q)$(MAKE) $(build)=$(@)

# Things we need to do before we recursively start building the kernel
# or the modules are listed in "prepare".
# A multi level approach is used. prepareN is processed before prepareN-1.
# archprepare is used in arch Makefiles and when processed asm symlink,
# version.h and scripts_basic is processed / created.

PHONY += prepare archprepare

archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
	asm-generic $(version_h) include/generated/utsrelease.h \
	include/generated/compile.h include/generated/autoconf.h remove-stale-files

prepare0: archprepare
	$(Q)$(MAKE) $(build)=scripts/mod
	$(Q)$(MAKE) $(build)=. prepare

# All the preparing..
prepare: prepare0
ifdef CONFIG_RUST
	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh -v
	$(Q)$(MAKE) $(build)=rust
endif

PHONY += remove-stale-files
remove-stale-files:
	$(Q)$(srctree)/scripts/remove-stale-files

# Support for using generic headers in asm-generic
asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj

PHONY += asm-generic uapi-asm-generic
asm-generic: uapi-asm-generic
	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
	generic=include/asm-generic
uapi-asm-generic:
	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
	generic=include/uapi/asm-generic

# Generate some files
# ---------------------------------------------------------------------------

# KERNELRELEASE can change from a few different places, meaning version.h
# needs to be updated, so this check is forced on all builds

uts_len := 64
define filechk_utsrelease.h
	if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
	  exit 1;                                                         \
	fi;                                                               \
	echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
endef

define filechk_version.h
	if [ $(SUBLEVEL) -gt 255 ]; then                                 \
		echo \#define LINUX_VERSION_CODE $(shell                 \
		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
	else                                                             \
		echo \#define LINUX_VERSION_CODE $(shell                 \
		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
	fi;                                                              \
	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
	((c) > 255 ? 255 : (c)))';                                       \
	echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
	echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
	echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
endef

$(version_h): PATCHLEVEL := $(or $(PATCHLEVEL), 0)
$(version_h): SUBLEVEL := $(or $(SUBLEVEL), 0)
$(version_h): FORCE
	$(call filechk,version.h)

include/generated/utsrelease.h: include/config/kernel.release FORCE
	$(call filechk,utsrelease.h)

filechk_compile.h = $(srctree)/scripts/mkcompile_h \
	"$(UTS_MACHINE)" "$(CONFIG_CC_VERSION_TEXT)" "$(LD)"

include/generated/compile.h: FORCE
	$(call filechk,compile.h)

PHONY += headerdep
headerdep:
	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
	$(srctree)/scripts/headerdep.pl -I$(srctree)/include

# ---------------------------------------------------------------------------
# Kernel headers

#Default location for installed headers
export INSTALL_HDR_PATH = $(objtree)/usr

quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
      cmd_headers_install = \
	mkdir -p $(INSTALL_HDR_PATH); \
	rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
	usr/include $(INSTALL_HDR_PATH)

PHONY += headers_install
headers_install: headers
	$(call cmd,headers_install)

PHONY += archheaders archscripts

hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj

PHONY += headers
headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
	$(if $(filter um, $(SRCARCH)), $(error Headers not exportable for UML))
	$(Q)$(MAKE) $(hdr-inst)=include/uapi
	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi

ifdef CONFIG_HEADERS_INSTALL
prepare: headers
endif

PHONY += scripts_unifdef
scripts_unifdef: scripts_basic
	$(Q)$(MAKE) $(build)=scripts scripts/unifdef

# ---------------------------------------------------------------------------
# Install

# Many distributions have the custom install script, /sbin/installkernel.
# If DKMS is installed, 'make install' will eventually recurse back
# to this Makefile to build and install external modules.
# Cancel sub_make_done so that options such as M=, V=, etc. are parsed.

quiet_cmd_install = INSTALL $(INSTALL_PATH)
      cmd_install = unset sub_make_done; $(srctree)/scripts/install.sh

# ---------------------------------------------------------------------------
# Tools

ifdef CONFIG_OBJTOOL
prepare: tools/objtool
endif

ifdef CONFIG_BPF
ifdef CONFIG_DEBUG_INFO_BTF
prepare: tools/bpf/resolve_btfids
endif
endif

PHONY += resolve_btfids_clean

resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids

# tools/bpf/resolve_btfids directory might not exist
# in output directory, skip its clean in that case
resolve_btfids_clean:
ifneq ($(wildcard $(resolve_btfids_O)),)
	$(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
endif

# Clear a bunch of variables before executing the submake
ifeq ($(quiet),silent_)
tools_silent=s
endif

tools/: FORCE
	$(Q)mkdir -p $(objtree)/tools
	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/

tools/%: FORCE
	$(Q)mkdir -p $(objtree)/tools
	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*

# ---------------------------------------------------------------------------
# Kernel selftest

PHONY += kselftest
kselftest: headers
	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests

kselftest-%: headers FORCE
	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*

PHONY += kselftest-merge
kselftest-merge:
	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
	$(Q)find $(srctree)/tools/testing/selftests -name config | \
		xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
	$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig

# ---------------------------------------------------------------------------
# Devicetree files

ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
dtstree := arch/$(SRCARCH)/boot/dts
endif

ifneq ($(dtstree),)

%.dtb: dtbs_prepare
	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@

%.dtbo: dtbs_prepare
	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@

PHONY += dtbs dtbs_prepare dtbs_install dtbs_check
dtbs: dtbs_prepare
	$(Q)$(MAKE) $(build)=$(dtstree)

# include/config/kernel.release is actually needed when installing DTBs because
# INSTALL_DTBS_PATH contains $(KERNELRELEASE). However, we do not want to make
# dtbs_install depend on it as dtbs_install may run as root.
dtbs_prepare: include/config/kernel.release scripts_dtc

ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
export CHECK_DTBS=y
endif

ifneq ($(CHECK_DTBS),)
dtbs_prepare: dt_binding_check
endif

dtbs_check: dtbs

dtbs_install:
	$(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)

ifdef CONFIG_OF_EARLY_FLATTREE
all: dtbs
endif

endif

PHONY += scripts_dtc
scripts_dtc: scripts_basic
	$(Q)$(MAKE) $(build)=scripts/dtc

ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
export CHECK_DT_BINDING=y
endif

PHONY += dt_binding_check
dt_binding_check: scripts_dtc
	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings

PHONY += dt_compatible_check
dt_compatible_check: dt_binding_check
	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@

# ---------------------------------------------------------------------------
# Modules

ifdef CONFIG_MODULES

# By default, build modules as well

all: modules

# When we're building modules with modversions, we need to consider
# the built-in objects during the descend as well, in order to
# make sure the checksums are up to date before we record them.
ifdef CONFIG_MODVERSIONS
  KBUILD_BUILTIN := 1
endif

# Build modules
#

# *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFO_BTF_MODULES
# is an exception.
ifdef CONFIG_DEBUG_INFO_BTF_MODULES
KBUILD_BUILTIN := 1
modules: vmlinux
endif

modules: modules_prepare

# Target to prepare building external modules
modules_prepare: prepare
	$(Q)$(MAKE) $(build)=scripts scripts/module.lds

export modules_sign_only :=

ifeq ($(CONFIG_MODULE_SIG),y)
PHONY += modules_sign
modules_sign: modules_install
	@:

# modules_sign is a subset of modules_install.
# 'make modules_install modules_sign' is equivalent to 'make modules_install'.
ifeq ($(filter modules_install,$(MAKECMDGOALS)),)
modules_sign_only := y
endif
endif

endif # CONFIG_MODULES

modinst_pre :=
ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
modinst_pre := __modinst_pre
endif

modules_install: $(modinst_pre)
PHONY += __modinst_pre
__modinst_pre:
	@rm -rf $(MODLIB)/kernel
	@rm -f $(MODLIB)/source
	@mkdir -p $(MODLIB)
ifdef CONFIG_MODULES
	@ln -s $(abspath $(srctree)) $(MODLIB)/source
	@if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
		rm -f $(MODLIB)/build ; \
		ln -s $(CURDIR) $(MODLIB)/build ; \
	fi
	@sed 's:^\(.*\)\.o$$:kernel/\1.ko:' modules.order > $(MODLIB)/modules.order
endif
	@cp -f modules.builtin $(MODLIB)/
	@cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/

###
# Cleaning is done on three levels.
# make clean     Delete most generated files
#                Leave enough to build external modules
# make mrproper  Delete the current configuration, and all generated files
# make distclean Remove editor backup files, patch leftover files and the like

# Directories & files removed with 'make clean'
CLEAN_FILES += include/ksym vmlinux.symvers modules-only.symvers \
	       modules.builtin modules.builtin.modinfo modules.nsdeps \
	       compile_commands.json .thinlto-cache rust/test rust/doc \
	       rust-project.json .vmlinux.objs .vmlinux.export.c

# Directories & files removed with 'make mrproper'
MRPROPER_FILES += include/config include/generated          \
		  arch/$(SRCARCH)/include/generated .objdiff \
		  debian snap tar-install \
		  .config .config.old .version \
		  Module.symvers \
		  certs/signing_key.pem \
		  certs/x509.genkey \
		  vmlinux-gdb.py \
		  *.spec rpmbuild \
		  rust/libmacros.so

# clean - Delete most, but leave enough to build external modules
#
clean: rm-files := $(CLEAN_FILES)

PHONY += archclean vmlinuxclean

vmlinuxclean:
	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
	$(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)

clean: archclean vmlinuxclean resolve_btfids_clean

# mrproper - Delete all generated files, including .config
#
mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
mrproper-dirs      := $(addprefix _mrproper_,scripts)

PHONY += $(mrproper-dirs) mrproper
$(mrproper-dirs):
	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)

mrproper: clean $(mrproper-dirs)
	$(call cmd,rmfiles)
	@find . $(RCS_FIND_IGNORE) \
		\( -name '*.rmeta' \) \
		-type f -print | xargs rm -f

# distclean
#
PHONY += distclean

distclean: mrproper
	@find . $(RCS_FIND_IGNORE) \
		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
		-o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
		-o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
		-type f -print | xargs rm -f


# Packaging of the kernel to various formats
# ---------------------------------------------------------------------------

%src-pkg: FORCE
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
%pkg: include/config/kernel.release FORCE
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@

# Brief documentation of the typical targets used
# ---------------------------------------------------------------------------

boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
boards := $(sort $(notdir $(boards)))
board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
board-dirs := $(sort $(notdir $(board-dirs:/=)))

PHONY += help
help:
	@echo  'Cleaning targets:'
	@echo  '  clean		  - Remove most generated files but keep the config and'
	@echo  '                    enough build support to build external modules'
	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
	@echo  ''
	@echo  'Configuration targets:'
	@$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
	@echo  ''
	@echo  'Other generic targets:'
	@echo  '  all		  - Build all targets marked with [*]'
	@echo  '* vmlinux	  - Build the bare kernel'
	@echo  '* modules	  - Build all modules'
	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
	@echo  '  dir/            - Build all files in dir and below'
	@echo  '  dir/file.[ois]  - Build specified target only'
	@echo  '  dir/file.ll     - Build the LLVM assembly file'
	@echo  '                    (requires compiler support for LLVM assembly generation)'
	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
	@echo  '                    (requires a recent binutils and recent build (System.map))'
	@echo  '  dir/file.ko     - Build module including final link'
	@echo  '  modules_prepare - Set up for building external modules'
	@echo  '  tags/TAGS	  - Generate tags file for editors'
	@echo  '  cscope	  - Generate cscope index'
	@echo  '  gtags           - Generate GNU GLOBAL index'
	@echo  '  kernelrelease	  - Output the release version string (use with make -s)'
	@echo  '  kernelversion	  - Output the version stored in Makefile (use with make -s)'
	@echo  '  image_name	  - Output the image name (use with make -s)'
	@echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
	 echo  ''
	@echo  'Static analysers:'
	@echo  '  checkstack      - Generate a list of stack hogs'
	@echo  '  versioncheck    - Sanity check on version.h usage'
	@echo  '  includecheck    - Check for duplicate included header files'
	@echo  '  export_report   - List the usages of all exported symbols'
	@echo  '  headerdep       - Detect inclusion cycles in headers'
	@echo  '  coccicheck      - Check with Coccinelle'
	@echo  '  clang-analyzer  - Check with clang static analyzer'
	@echo  '  clang-tidy      - Check with clang-tidy'
	@echo  ''
	@echo  'Tools:'
	@echo  '  nsdeps          - Generate missing symbol namespace dependencies'
	@echo  ''
	@echo  'Kernel selftest:'
	@echo  '  kselftest         - Build and run kernel selftest'
	@echo  '                      Build, install, and boot kernel before'
	@echo  '                      running kselftest on it'
	@echo  '                      Run as root for full coverage'
	@echo  '  kselftest-all     - Build kernel selftest'
	@echo  '  kselftest-install - Build and install kernel selftest'
	@echo  '  kselftest-clean   - Remove all generated kselftest files'
	@echo  '  kselftest-merge   - Merge all the config dependencies of'
	@echo  '		      kselftest to existing .config.'
	@echo  ''
	@echo  'Rust targets:'
	@echo  '  rustavailable   - Checks whether the Rust toolchain is'
	@echo  '		    available and, if not, explains why.'
	@echo  '  rustfmt	  - Reformat all the Rust code in the kernel'
	@echo  '  rustfmtcheck	  - Checks if all the Rust code in the kernel'
	@echo  '		    is formatted, printing a diff otherwise.'
	@echo  '  rustdoc	  - Generate Rust documentation'
	@echo  '		    (requires kernel .config)'
	@echo  '  rusttest        - Runs the Rust tests'
	@echo  '                    (requires kernel .config; downloads external repos)'
	@echo  '  rust-analyzer	  - Generate rust-project.json rust-analyzer support file'
	@echo  '		    (requires kernel .config)'
	@echo  '  dir/file.[os]   - Build specified target only'
	@echo  '  dir/file.rsi    - Build macro expanded source, similar to C preprocessing.'
	@echo  '                    Run with RUSTFMT=n to skip reformatting if needed.'
	@echo  '                    The output is not intended to be compilable.'
	@echo  '  dir/file.ll     - Build the LLVM assembly file'
	@echo  ''
	@$(if $(dtstree), \
		echo 'Devicetree:'; \
		echo '* dtbs             - Build device tree blobs for enabled boards'; \
		echo '  dtbs_install     - Install dtbs to $(INSTALL_DTBS_PATH)'; \
		echo '  dt_binding_check - Validate device tree binding documents'; \
		echo '  dtbs_check       - Validate device tree source files';\
		echo '')

	@echo 'Userspace tools targets:'
	@echo '  use "make tools/help"'
	@echo '  or  "cd tools; make help"'
	@echo  ''
	@echo  'Kernel packaging:'
	@$(MAKE) -f $(srctree)/scripts/Makefile.package help
	@echo  ''
	@echo  'Documentation targets:'
	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
	@echo  ''
	@echo  'Architecture specific targets ($(SRCARCH)):'
	@$(or $(archhelp),\
		echo '  No architecture specific help defined for $(SRCARCH)')
	@echo  ''
	@$(if $(boards), \
		$(foreach b, $(boards), \
		printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
		echo '')
	@$(if $(board-dirs), \
		$(foreach b, $(board-dirs), \
		printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
		printf "  %-16s - Show all of the above\\n" help-boards; \
		echo '')

	@echo  '  make V=n   [targets] 1: verbose build'
	@echo  '                       2: give reason for rebuild of target'
	@echo  '                       V=1 and V=2 can be combined with V=12'
	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
	@echo  '                       (sparse by default)'
	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
	@echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
	@echo  '		1: warnings which may be relevant and do not occur too often'
	@echo  '		2: warnings which occur quite often but may still be relevant'
	@echo  '		3: more obscure warnings, can most likely be ignored'
	@echo  '		e: warnings are being treated as errors'
	@echo  '		Multiple levels can be combined with W=12 or W=123'
	@$(if $(dtstree), \
		echo '  make CHECK_DTBS=1 [targets] Check all generated dtb files against schema'; \
		echo '         This can be applied both to "dtbs" and to individual "foo.dtb" targets' ; \
		)
	@echo  ''
	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
	@echo  'For further info see the ./README file'


help-board-dirs := $(addprefix help-,$(board-dirs))

help-boards: $(help-board-dirs)

boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))

$(help-board-dirs): help-%:
	@echo  'Architecture specific targets ($(SRCARCH) $*):'
	@$(if $(boards-per-dir), \
		$(foreach b, $(boards-per-dir), \
		printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
		echo '')


# Documentation targets
# ---------------------------------------------------------------------------
DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
	       linkcheckdocs dochelp refcheckdocs texinfodocs infodocs
PHONY += $(DOC_TARGETS)
$(DOC_TARGETS):
	$(Q)$(MAKE) $(build)=Documentation $@


# Rust targets
# ---------------------------------------------------------------------------

# "Is Rust available?" target
PHONY += rustavailable
rustavailable:
	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh -v && echo "Rust is available!"

# Documentation target
#
# Using the singular to avoid running afoul of `no-dot-config-targets`.
PHONY += rustdoc
rustdoc: prepare
	$(Q)$(MAKE) $(build)=rust $@

# Testing target
PHONY += rusttest
rusttest: prepare
	$(Q)$(MAKE) $(build)=rust $@

# Formatting targets
PHONY += rustfmt rustfmtcheck

# We skip `rust/alloc` since we want to minimize the diff w.r.t. upstream.
#
# We match using absolute paths since `find` does not resolve them
# when matching, which is a problem when e.g. `srctree` is `..`.
# We `grep` afterwards in order to remove the directory entry itself.
rustfmt:
	$(Q)find $(abs_srctree) -type f -name '*.rs' \
		-o -path $(abs_srctree)/rust/alloc -prune \
		-o -path $(abs_objtree)/rust/test -prune \
		| grep -Fv $(abs_srctree)/rust/alloc \
		| grep -Fv $(abs_objtree)/rust/test \
		| grep -Fv generated \
		| xargs $(RUSTFMT) $(rustfmt_flags)

rustfmtcheck: rustfmt_flags = --check
rustfmtcheck: rustfmt

# IDE support targets
PHONY += rust-analyzer
rust-analyzer:
	$(Q)$(MAKE) $(build)=rust $@

# Misc
# ---------------------------------------------------------------------------

PHONY += misc-check
misc-check:
	$(Q)$(srctree)/scripts/misc-check

all: misc-check

PHONY += scripts_gdb
scripts_gdb: prepare0
	$(Q)$(MAKE) $(build)=scripts/gdb
	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)

ifdef CONFIG_GDB_SCRIPTS
all: scripts_gdb
endif

else # KBUILD_EXTMOD

filechk_kernel.release = echo $(KERNELRELEASE)

###
# External module support.
# When building external modules the kernel used as basis is considered
# read-only, and no consistency checks are made and the make
# system is not used on the basis kernel. If updates are required
# in the basis kernel ordinary make commands (without M=...) must be used.

# We are always building only modules.
KBUILD_BUILTIN :=
KBUILD_MODULES := 1

build-dir := $(KBUILD_EXTMOD)

compile_commands.json: $(extmod_prefix)compile_commands.json
PHONY += compile_commands.json

clean-dirs := $(KBUILD_EXTMOD)
clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
	$(KBUILD_EXTMOD)/compile_commands.json $(KBUILD_EXTMOD)/.thinlto-cache

PHONY += prepare
# now expand this into a simple variable to reduce the cost of shell evaluations
prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT)
prepare:
	@if [ "$(CC_VERSION_TEXT)" != "$(CONFIG_CC_VERSION_TEXT)" ]; then \
		echo >&2 "warning: the compiler differs from the one used to build the kernel"; \
		echo >&2 "  The kernel was built by: $(CONFIG_CC_VERSION_TEXT)"; \
		echo >&2 "  You are using:           $(CC_VERSION_TEXT)"; \
	fi

PHONY += help
help:
	@echo  '  Building external modules.'
	@echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
	@echo  ''
	@echo  '  modules         - default target, build the module(s)'
	@echo  '  modules_install - install the module'
	@echo  '  clean           - remove generated files in module directory only'
	@echo  ''

__external_modules_error:
	@echo >&2 '***'
	@echo >&2 '*** The present kernel disabled CONFIG_MODULES.'
	@echo >&2 '*** You cannot build or install external modules.'
	@echo >&2 '***'
	@false

endif # KBUILD_EXTMOD

# ---------------------------------------------------------------------------
# Modules

PHONY += modules modules_install modules_prepare

ifdef CONFIG_MODULES

$(MODORDER): $(build-dir)
	@:

# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
# This is solely useful to speed up test compiles.
modules: modpost
ifneq ($(KBUILD_MODPOST_NOFINAL),1)
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
endif

PHONY += modules_check
modules_check: $(MODORDER)
	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<

quiet_cmd_depmod = DEPMOD  $(MODLIB)
      cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
                   $(KERNELRELEASE)

modules_install:
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
	$(call cmd,depmod)

else # CONFIG_MODULES

# Modules not configured
# ---------------------------------------------------------------------------

PHONY += __external_modules_error

modules modules_install: __external_modules_error
	@:

KBUILD_MODULES :=

endif # CONFIG_MODULES

PHONY += modpost
modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \
	 $(if $(KBUILD_MODULES), modules_check)
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost

# Single targets
# ---------------------------------------------------------------------------
# To build individual files in subdirectories, you can do like this:
#
#   make foo/bar/baz.s
#
# The supported suffixes for single-target are listed in 'single-targets'
#
# To build only under specific subdirectories, you can do like this:
#
#   make foo/bar/baz/

ifdef single-build

# .ko is special because modpost is needed