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# SPDX-License-Identifier: GPL-2.0
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VERSION = 5
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PATCHLEVEL = 14
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SUBLEVEL = 0
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EXTRAVERSION =
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NAME = Opossums on Parade
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# *DOCUMENTATION*
# To see a list of typical targets execute "make help"
# More info can be located in ./README
# Comments in this file are targeted only to the developer, do not
# expect to learn how to build the kernel reading this file.

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$(if $(filter __%, $(MAKECMDGOALS)), \
	$(error targets prefixed with '__' are only for internal use))

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# That's our default target when none is given on the command line
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PHONY := __all
__all:
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# We are using a recursive build, so we need to do a little thinking
# to get the ordering right.
#
# Most importantly: sub-Makefiles should only ever modify files in
# their own directory. If in some directory we have a dependency on
# a file in another dir (which doesn't happen often, but it's often
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# unavoidable when linking the built-in.a targets which finally
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# turn into vmlinux), we will call a sub make in that other dir, and
# after that we are sure that everything which is in that other dir
# is now up to date.
#
# The only cases where we need to modify files which have global
# effects are thus separated out and done before the recursive
# descending is started. They are now explicitly listed as the
# prepare rule.

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ifneq ($(sub_make_done),1)
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# Do not use make's built-in rules and variables
# (this increases performance and avoids hard-to-debug behaviour)
MAKEFLAGS += -rR

# Avoid funny character set dependencies
unexport LC_ALL
LC_COLLATE=C
LC_NUMERIC=C
export LC_COLLATE LC_NUMERIC

# Avoid interference with shell env settings
unexport GREP_OPTIONS

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# Beautify output
# ---------------------------------------------------------------------------
#
# Normally, we echo the whole command before executing it. By making
# that echo $($(quiet)$(cmd)), we now have the possibility to set
# $(quiet) to choose other forms of output instead, e.g.
#
#         quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
#         cmd_cc_o_c       = $(CC) $(c_flags) -c -o $@ $<
#
# If $(quiet) is empty, the whole command will be printed.
# If it is set to "quiet_", only the short version will be printed.
# If it is set to "silent_", nothing will be printed at all, since
# the variable $(silent_cmd_cc_o_c) doesn't exist.
#
# A simple variant is to prefix commands with $(Q) - that's useful
# for commands that shall be hidden in non-verbose mode.
#
#	$(Q)ln $@ :<
#
# If KBUILD_VERBOSE equals 0 then the above command will be hidden.
# If KBUILD_VERBOSE equals 1 then the above command is displayed.
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# If KBUILD_VERBOSE equals 2 then give the reason why each target is rebuilt.
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#
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# To put more focus on warnings, be less verbose as default
# Use 'make V=1' to see the full commands

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ifeq ("$(origin V)", "command line")
  KBUILD_VERBOSE = $(V)
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endif
ifndef KBUILD_VERBOSE
  KBUILD_VERBOSE = 0
endif

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ifeq ($(KBUILD_VERBOSE),1)
  quiet =
  Q =
else
  quiet=quiet_
  Q = @
endif

# If the user is running make -s (silent mode), suppress echoing of
# commands

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ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
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  quiet=silent_
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  KBUILD_VERBOSE = 0
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endif

export quiet Q KBUILD_VERBOSE

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# Call a source code checker (by default, "sparse") as part of the
# C compilation.
#
# Use 'make C=1' to enable checking of only re-compiled files.
# Use 'make C=2' to enable checking of *all* source files, regardless
# of whether they are re-compiled or not.
#
# See the file "Documentation/dev-tools/sparse.rst" for more details,
# including where to get the "sparse" utility.

ifeq ("$(origin C)", "command line")
  KBUILD_CHECKSRC = $(C)
endif
ifndef KBUILD_CHECKSRC
  KBUILD_CHECKSRC = 0
endif

export KBUILD_CHECKSRC

# Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
# directory of external module to build. Setting M= takes precedence.
ifeq ("$(origin M)", "command line")
  KBUILD_EXTMOD := $(M)
endif

$(if $(word 2, $(KBUILD_EXTMOD)), \
	$(error building multiple external modules is not supported))

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# Remove trailing slashes
ifneq ($(filter %/, $(KBUILD_EXTMOD)),)
KBUILD_EXTMOD := $(shell dirname $(KBUILD_EXTMOD).)
endif

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export KBUILD_EXTMOD

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# Kbuild will save output files in the current working directory.
# This does not need to match to the root of the kernel source tree.
#
# For example, you can do this:
#
#  cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
#
# If you want to save output files in a different location, there are
# two syntaxes to specify it.
#
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# 1) O=
# Use "make O=dir/to/store/output/files/"
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#
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# 2) Set KBUILD_OUTPUT
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# Set the environment variable KBUILD_OUTPUT to point to the output directory.
# export KBUILD_OUTPUT=dir/to/store/output/files/; make
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#
# The O= assignment takes precedence over the KBUILD_OUTPUT environment
# variable.

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# Do we want to change the working directory?
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ifeq ("$(origin O)", "command line")
  KBUILD_OUTPUT := $(O)
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endif

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ifneq ($(KBUILD_OUTPUT),)
# Make's built-in functions such as $(abspath ...), $(realpath ...) cannot
# expand a shell special character '~'. We use a somewhat tedious way here.
abs_objtree := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) && pwd)
$(if $(abs_objtree),, \
     $(error failed to create output directory "$(KBUILD_OUTPUT)"))

# $(realpath ...) resolves symlinks
abs_objtree := $(realpath $(abs_objtree))
else
abs_objtree := $(CURDIR)
endif # ifneq ($(KBUILD_OUTPUT),)

ifeq ($(abs_objtree),$(CURDIR))
# Suppress "Entering directory ..." unless we are changing the work directory.
MAKEFLAGS += --no-print-directory
else
need-sub-make := 1
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endif

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this-makefile := $(lastword $(MAKEFILE_LIST))
abs_srctree := $(realpath $(dir $(this-makefile)))
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ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
$(error source directory cannot contain spaces or colons)
endif
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ifneq ($(abs_srctree),$(abs_objtree))
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# Look for make include files relative to root of kernel src
#
# This does not become effective immediately because MAKEFLAGS is re-parsed
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# once after the Makefile is read. We need to invoke sub-make.
MAKEFLAGS += --include-dir=$(abs_srctree)
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need-sub-make := 1
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endif
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ifneq ($(filter 3.%,$(MAKE_VERSION)),)
# 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
# We need to invoke sub-make to avoid implicit rules in the top Makefile.
need-sub-make := 1
# Cancel implicit rules for this Makefile.
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$(this-makefile): ;
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endif

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export abs_srctree abs_objtree
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export sub_make_done := 1

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ifeq ($(need-sub-make),1)

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PHONY += $(MAKECMDGOALS) __sub-make
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$(filter-out $(this-makefile), $(MAKECMDGOALS)) __all: __sub-make
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	@:
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# Invoke a second make in the output directory, passing relevant variables
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__sub-make:
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	$(Q)$(MAKE) -C $(abs_objtree) -f $(abs_srctree)/Makefile $(MAKECMDGOALS)
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endif # need-sub-make
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endif # sub_make_done
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# We process the rest of the Makefile if this is the final invocation of make
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ifeq ($(need-sub-make),)
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# Do not print "Entering directory ...",
# but we want to display it when entering to the output directory
# so that IDEs/editors are able to understand relative filenames.
MAKEFLAGS += --no-print-directory

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ifeq ($(abs_srctree),$(abs_objtree))
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        # building in the source tree
        srctree := .
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	building_out_of_srctree :=
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else
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        ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
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                # building in a subdirectory of the source tree
                srctree := ..
        else
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                srctree := $(abs_srctree)
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        endif
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	building_out_of_srctree := 1
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endif
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ifneq ($(KBUILD_ABS_SRCTREE),)
srctree := $(abs_srctree)
endif
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objtree		:= .
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VPATH		:= $(srctree)
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export building_out_of_srctree srctree objtree VPATH
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# To make sure we do not include .config for any of the *config targets
# catch them early, and hand them over to scripts/kconfig/Makefile
# It is allowed to specify more targets when calling make, including
# mixing *config targets and build targets.
# For example 'make oldconfig all'.
# Detect when mixed targets is specified, and make a second invocation
# of make so .config is not included in this case either (for *config).

version_h := include/generated/uapi/linux/version.h

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clean-targets := %clean mrproper cleandocs
no-dot-config-targets := $(clean-targets) \
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			 cscope gtags TAGS tags help% %docs check% coccicheck \
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			 $(version_h) headers headers_% archheaders archscripts \
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			 %asm-generic kernelversion %src-pkg dt_binding_check \
			 outputmakefile
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# Installation targets should not require compiler. Unfortunately, vdso_install
# is an exception where build artifacts may be updated. This must be fixed.
no-compiler-targets := $(no-dot-config-targets) install dtbs_install \
			headers_install modules_install kernelrelease image_name
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no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease \
			  image_name
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single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
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config-build	:=
mixed-build	:=
need-config	:= 1
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need-compiler	:= 1
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may-sync-config	:= 1
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single-build	:=
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ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
	ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
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		need-config :=
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	endif
endif

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ifneq ($(filter $(no-compiler-targets), $(MAKECMDGOALS)),)
	ifeq ($(filter-out $(no-compiler-targets), $(MAKECMDGOALS)),)
		need-compiler :=
	endif
endif

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ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
	ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
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		may-sync-config :=
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	endif
endif

ifneq ($(KBUILD_EXTMOD),)
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	may-sync-config :=
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endif

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ifeq ($(KBUILD_EXTMOD),)
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        ifneq ($(filter %config,$(MAKECMDGOALS)),)
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		config-build := 1
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                ifneq ($(words $(MAKECMDGOALS)),1)
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			mixed-build := 1
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                endif
        endif
endif
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# We cannot build single targets and the others at the same time
ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
	single-build := 1
	ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
		mixed-build := 1
	endif
endif

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# For "make -j clean all", "make -j mrproper defconfig all", etc.
ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
        ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
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		mixed-build := 1
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        endif
endif

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# install and modules_install need also be processed one by one
ifneq ($(filter install,$(MAKECMDGOALS)),)
        ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
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		mixed-build := 1
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        endif
endif

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ifdef mixed-build
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# ===========================================================================
# We're called with mixed targets (*config and build targets).
# Handle them one by one.

PHONY += $(MAKECMDGOALS) __build_one_by_one

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$(MAKECMDGOALS): __build_one_by_one
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	@:

__build_one_by_one:
	$(Q)set -e; \
	for i in $(MAKECMDGOALS); do \
		$(MAKE) -f $(srctree)/Makefile $$i; \
	done

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else # !mixed-build
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include $(srctree)/scripts/Kbuild.include
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# 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

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include $(srctree)/scripts/subarch.include
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# Cross compiling and selecting different set of gcc/bin-utils
# ---------------------------------------------------------------------------
#
# When performing cross compilation for other architectures ARCH shall be set
# to the target architecture. (See arch/* for the possibilities).
# ARCH can be set during invocation of make:
# make ARCH=ia64
# Another way is to have ARCH set in the environment.
# The default ARCH is the host where make is executed.

# CROSS_COMPILE specify the prefix used for all executables used
# during compilation. Only gcc and related bin-utils executables
# are prefixed with $(CROSS_COMPILE).
# CROSS_COMPILE can be set on the command line
# make CROSS_COMPILE=ia64-linux-
# Alternatively CROSS_COMPILE can be set in the environment.
# Default value for CROSS_COMPILE is not to prefix executables
# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
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ARCH		?= $(SUBARCH)
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# Architecture as present in compile.h
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UTS_MACHINE 	:= $(ARCH)
SRCARCH 	:= $(ARCH)
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# Additional ARCH settings for x86
ifeq ($(ARCH),i386)
        SRCARCH := x86
endif
ifeq ($(ARCH),x86_64)
        SRCARCH := x86
endif
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# Additional ARCH settings for sparc
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ifeq ($(ARCH),sparc32)
       SRCARCH := sparc
endif
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ifeq ($(ARCH),sparc64)
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       SRCARCH := sparc
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endif
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export cross_compiling :=
ifneq ($(SRCARCH),$(SUBARCH))
cross_compiling := 1
endif

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KCONFIG_CONFIG	?= .config
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export KCONFIG_CONFIG
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# SHELL used by kbuild
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CONFIG_SHELL := sh
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HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
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ifneq ($(LLVM),)
HOSTCC	= clang
HOSTCXX	= clang++
else
HOSTCC	= gcc
HOSTCXX	= g++
endif
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export KBUILD_USERCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
			      -O2 -fomit-frame-pointer -std=gnu89
export KBUILD_USERLDFLAGS :=

KBUILD_HOSTCFLAGS   := $(KBUILD_USERCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
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KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
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KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
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# Make variables (CC, etc...)
CPP		= $(CC) -E
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ifneq ($(LLVM),)
CC		= clang
LD		= ld.lld
AR		= llvm-ar
NM		= llvm-nm
OBJCOPY		= llvm-objcopy
OBJDUMP		= llvm-objdump
READELF		= llvm-readelf
STRIP		= llvm-strip
else
CC		= $(CROSS_COMPILE)gcc
LD		= $(CROSS_COMPILE)ld
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AR		= $(CROSS_COMPILE)ar
NM		= $(CROSS_COMPILE)nm
OBJCOPY		= $(CROSS_COMPILE)objcopy
OBJDUMP		= $(CROSS_COMPILE)objdump
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READELF		= $(CROSS_COMPILE)readelf
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STRIP		= $(CROSS_COMPILE)strip
endif
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PAHOLE		= pahole
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RESOLVE_BTFIDS	= $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
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LEX		= flex
YACC		= bison
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AWK		= awk
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INSTALLKERNEL  := installkernel
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DEPMOD		= depmod
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PERL		= perl
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PYTHON3		= python3
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CHECK		= sparse
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BASH		= bash
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KGZIP		= gzip
KBZIP2		= bzip2
KLZOP		= lzop
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LZMA		= lzma
LZ4		= lz4c
XZ		= xz
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ZSTD		= zstd
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CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
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		  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
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NOSTDINC_FLAGS :=
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CFLAGS_MODULE   =
AFLAGS_MODULE   =
LDFLAGS_MODULE  =
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CFLAGS_KERNEL	=
AFLAGS_KERNEL	=
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LDFLAGS_vmlinux =
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# Use USERINCLUDE when you must reference the UAPI directories only.
USERINCLUDE    := \
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		-I$(srctree)/arch/$(SRCARCH)/include/uapi \
		-I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
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		-I$(srctree)/include/uapi \
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		-I$(objtree)/include/generated/uapi \
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                -include $(srctree)/include/linux/compiler-version.h \
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                -include $(srctree)/include/linux/kconfig.h

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# Use LINUXINCLUDE when you must reference the include/ directory.
# Needed to be compatible with the O= option
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LINUXINCLUDE    := \
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		-I$(srctree)/arch/$(SRCARCH)/include \
		-I$(objtree)/arch/$(SRCARCH)/include/generated \
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		$(if $(building_out_of_srctree),-I$(srctree)/include) \
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		-I$(objtree)/include \
		$(USERINCLUDE)
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KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
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KBUILD_CFLAGS   := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
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		   -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
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		   -Werror=implicit-function-declaration -Werror=implicit-int \
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		   -Werror=return-type -Wno-format-security \
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		   -std=gnu89
KBUILD_CPPFLAGS := -D__KERNEL__
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KBUILD_AFLAGS_KERNEL :=
KBUILD_CFLAGS_KERNEL :=
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KBUILD_AFLAGS_MODULE  := -DMODULE
KBUILD_CFLAGS_MODULE  := -DMODULE
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KBUILD_LDFLAGS_MODULE :=
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KBUILD_LDFLAGS :=
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CLANG_FLAGS :=
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export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC
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export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
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export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
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export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
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export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
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export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
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export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
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export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
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export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
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export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
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# Files to ignore in find ... statements

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export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
			  -name CVS -o -name .pc -o -name .hg -o -name .git \) \
			  -prune -o
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export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
			 --exclude CVS --exclude .pc --exclude .hg --exclude .git
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# ===========================================================================
# Rules shared between *config targets and build targets

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# Basic helpers built in scripts/basic/
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PHONY += scripts_basic
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scripts_basic:
	$(Q)$(MAKE) $(build)=scripts/basic

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PHONY += outputmakefile
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ifdef building_out_of_srctree
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# Before starting out-of-tree build, make sure the source tree is clean.
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# outputmakefile generates a Makefile in the output directory, if using a
# separate output directory. This allows convenient use of make in the
# output directory.
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# At the same time when output Makefile generated, generate .gitignore to
# ignore whole output directory
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quiet_cmd_makefile = GEN     Makefile
      cmd_makefile = { \
	echo "\# Automatically generated by $(srctree)/Makefile: don't edit"; \
	echo "include $(srctree)/Makefile"; \
	} > Makefile

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outputmakefile:
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	$(Q)if [ -f $(srctree)/.config -o \
		 -d $(srctree)/include/config -o \
		 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
		echo >&2 "***"; \
		echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
		echo >&2 "*** in $(abs_srctree)";\
		echo >&2 "***"; \
		false; \
	fi
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	$(Q)ln -fsn $(srctree) source
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	$(call cmd,makefile)
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	$(Q)test -e .gitignore || \
	{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
579
endif
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581 582 583 584
# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
# and from include/config/auto.conf.cmd to detect the compiler upgrade.
585
CC_VERSION_TEXT = $(subst $(pound),,$(shell $(CC) --version 2>/dev/null | head -n 1))
586 587

ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
588
ifneq ($(CROSS_COMPILE),)
589
CLANG_FLAGS	+= --target=$(notdir $(CROSS_COMPILE:%-=%))
590
endif
591 592 593
ifeq ($(LLVM_IAS),1)
CLANG_FLAGS	+= -integrated-as
else
594
CLANG_FLAGS	+= -no-integrated-as
595 596
GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
CLANG_FLAGS	+= --prefix=$(GCC_TOOLCHAIN_DIR)$(notdir $(CROSS_COMPILE))
597
endif
598
CLANG_FLAGS	+= -Werror=unknown-warning-option
599 600
KBUILD_CFLAGS	+= $(CLANG_FLAGS)
KBUILD_AFLAGS	+= $(CLANG_FLAGS)
601
export CLANG_FLAGS
602 603
endif

604 605
# Include this also for config targets because some architectures need
# cc-cross-prefix to determine CROSS_COMPILE.
606
ifdef need-compiler
607
include $(srctree)/scripts/Makefile.compiler
608
endif
609

610
ifdef config-build
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# ===========================================================================
# *config targets only - make sure prerequisites are updated, and descend
# in scripts/kconfig to make the *config target

# Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
# KBUILD_DEFCONFIG may point out an alternative default configuration
# used for 'make defconfig'
618
include $(srctree)/arch/$(SRCARCH)/Makefile
619
export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
L
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620

621
config: outputmakefile scripts_basic FORCE
S
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622 623
	$(Q)$(MAKE) $(build)=scripts/kconfig $@

624
%config: outputmakefile scripts_basic FORCE
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625 626
	$(Q)$(MAKE) $(build)=scripts/kconfig $@

627
else #!config-build
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# ===========================================================================
# Build targets only - this includes vmlinux, arch specific targets, clean
# targets and others. In general all targets except *config targets.

632
# If building an external module we do not care about the all: rule
633
# but instead __all depend on modules
634 635
PHONY += all
ifeq ($(KBUILD_EXTMOD),)
636
__all: all
637
else
638
__all: modules
639 640 641 642 643 644 645 646 647 648
endif

# Decide whether to build built-in, modular, or both.
# Normally, just do built-in.

KBUILD_MODULES :=
KBUILD_BUILTIN := 1

# If we have only "make modules", don't compile built-in objects.
ifeq ($(MAKECMDGOALS),modules)
649
  KBUILD_BUILTIN :=
650 651 652 653 654 655
endif

# If we have "make <whatever> modules", compile modules
# in addition to whatever we do anyway.
# Just "make" or "make all" shall build modules as well

656
ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
657 658 659 660 661 662 663 664 665
  KBUILD_MODULES := 1
endif

ifeq ($(MAKECMDGOALS),)
  KBUILD_MODULES := 1
endif

export KBUILD_MODULES KBUILD_BUILTIN

666
ifdef need-config
667 668 669
include include/config/auto.conf
endif

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ifeq ($(KBUILD_EXTMOD),)
# Objects we will link into vmlinux / subdirs we need to visit
672
core-y		:= init/ usr/ arch/$(SRCARCH)/
673
drivers-y	:= drivers/ sound/
674
drivers-$(CONFIG_SAMPLES) += samples/
675 676
drivers-$(CONFIG_NET) += net/
drivers-y	+= virt/
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libs-y		:= lib/
endif # KBUILD_EXTMOD

680 681 682 683 684 685 686 687 688
# The all: target is the default when no target is given on the
# command line.
# This allow a user to issue only 'make' to build a kernel including modules
# Defaults to vmlinux, but the arch makefile usually adds further targets
all: vmlinux

CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage \
	$(call cc-option,-fno-tree-loop-im) \
	$(call cc-disable-warning,maybe-uninitialized,)
689
export CFLAGS_GCOV
690

691 692 693 694 695
# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
ifdef CONFIG_FUNCTION_TRACER
  CC_FLAGS_FTRACE := -pg
endif

696 697 698 699 700 701 702 703 704
RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
export RETPOLINE_CFLAGS
export RETPOLINE_VDSO_CFLAGS

705
include $(srctree)/arch/$(SRCARCH)/Makefile
L
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707 708
ifdef need-config
ifdef may-sync-config
709 710 711
# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
# because some architectures define CROSS_COMPILE there.
712
include include/config/auto.conf.cmd
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714 715 716 717 718 719 720 721
$(KCONFIG_CONFIG):
	@echo >&2 '***'
	@echo >&2 '*** Configuration file "$@" not found!'
	@echo >&2 '***'
	@echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
	@echo >&2 '*** "make menuconfig" or "make xconfig").'
	@echo >&2 '***'
	@/bin/false
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722

723 724 725
# The actual configuration files used during the build are stored in
# include/generated/ and include/config/. Update them if .config is newer than
# include/config/auto.conf (which mirrors .config).
726 727 728
#
# This exploits the 'multi-target pattern rule' trick.
# The syncconfig should be executed only once to make all the targets.
729
# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
730 731 732
#
# Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
# so you cannot notice that Kconfig is waiting for the user input.
733
%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h: $(KCONFIG_CONFIG)
734 735
	$(Q)$(kecho) "  SYNC    $@"
	$(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
736
else # !may-sync-config
737 738 739
# External modules and some install targets need include/generated/autoconf.h
# and include/config/auto.conf but do not care if they are up-to-date.
# Use auto.conf to trigger the test
740 741 742
PHONY += include/config/auto.conf

include/config/auto.conf:
743
	$(Q)test -e include/generated/autoconf.h -a -e $@ || (		\
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	echo >&2;							\
	echo >&2 "  ERROR: Kernel configuration is invalid.";		\
	echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
	echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";	\
	echo >&2 ;							\
749 750
	/bin/false)

751
endif # may-sync-config
752
endif # need-config
L
Linus Torvalds 已提交
753

754
KBUILD_CFLAGS	+= $(call cc-option,-fno-delete-null-pointer-checks,)
755
KBUILD_CFLAGS	+= $(call cc-disable-warning,frame-address,)
756 757
KBUILD_CFLAGS	+= $(call cc-disable-warning, format-truncation)
KBUILD_CFLAGS	+= $(call cc-disable-warning, format-overflow)
758
KBUILD_CFLAGS	+= $(call cc-disable-warning, address-of-packed-member)
759

760 761 762 763 764 765
ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
KBUILD_CFLAGS += -O2
else ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3
KBUILD_CFLAGS += -O3
else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
KBUILD_CFLAGS += -Os
766
endif
L
Linus Torvalds 已提交
767

768 769
# Tell gcc to never replace conditional load with a non-conditional one
KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
770
KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
771

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Andi Kleen 已提交
772 773 774 775 776 777 778 779 780 781
ifdef CONFIG_READABLE_ASM
# Disable optimizations that make assembler listings hard to read.
# reorder blocks reorders the control in the function
# ipa clone creates specialized cloned functions
# partial inlining inlines only parts of functions
KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
                 $(call cc-option,-fno-ipa-cp-clone,) \
                 $(call cc-option,-fno-partial-inlining)
endif

782
ifneq ($(CONFIG_FRAME_WARN),0)
783
KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
784 785
endif

786
stackp-flags-y                                    := -fno-stack-protector
787 788
stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
789 790

KBUILD_CFLAGS += $(stackp-flags-y)
791

792
ifdef CONFIG_CC_IS_CLANG
793 794 795
KBUILD_CPPFLAGS += -Qunused-arguments
KBUILD_CFLAGS += -Wno-format-invalid-specifier
KBUILD_CFLAGS += -Wno-gnu
796 797 798
# CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
# source of a reference will be _MergedGlobals and not on of the whitelisted names.
# See modpost pattern 2
799
KBUILD_CFLAGS += -mno-global-merge
800 801 802 803 804 805
else

# Warn about unmarked fall-throughs in switch statement.
# Disabled for clang while comment to attribute conversion happens and
# https://github.com/ClangBuiltLinux/linux/issues/636 is discussed.
KBUILD_CFLAGS += $(call cc-option,-Wimplicit-fallthrough=5,)
806 807
endif

808 809 810 811
# These warnings generated too much noise in a regular build.
# Use make W=1 to enable them (see scripts/Makefile.extrawarn)
KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)

812
KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
L
Linus Torvalds 已提交
813
ifdef CONFIG_FRAME_POINTER
814
KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
L
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815
else
816 817 818 819 820 821
# Some targets (ARM with Thumb2, for example), can't be built with frame
# pointers.  For those, we don't have FUNCTION_TRACER automatically
# select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
# incompatible with -fomit-frame-pointer with current GCC, so we don't use
# -fomit-frame-pointer with FUNCTION_TRACER.
ifndef CONFIG_FUNCTION_TRACER
822
KBUILD_CFLAGS	+= -fomit-frame-pointer
L
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823
endif
824
endif
L
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825

826 827
# Initialize all stack variables with a 0xAA pattern.
ifdef CONFIG_INIT_STACK_ALL_PATTERN
828 829 830
KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
endif

831 832 833 834 835 836 837 838 839
# Initialize all stack variables with a zero value.
ifdef CONFIG_INIT_STACK_ALL_ZERO
# Future support for zero initialization is still being debated, see
# https://bugs.llvm.org/show_bug.cgi?id=45497. These flags are subject to being
# renamed or dropped.
KBUILD_CFLAGS	+= -ftrivial-auto-var-init=zero
KBUILD_CFLAGS	+= -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
endif

840 841 842 843
# While VLAs have been removed, GCC produces unreachable stack probes
# for the randomize_kstack_offset feature. Disable it for all compilers.
KBUILD_CFLAGS	+= $(call cc-option, -fno-stack-clash-protection)

844 845
DEBUG_CFLAGS	:=

846 847 848
# Workaround for GCC versions < 5.0
# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61801
ifdef CONFIG_CC_IS_GCC
849
DEBUG_CFLAGS	+= $(call cc-ifversion, -lt, 0500, $(call cc-option, -fno-var-tracking-assignments))
850
endif
851

L
Linus Torvalds 已提交
852
ifdef CONFIG_DEBUG_INFO
853

A
Andi Kleen 已提交
854
ifdef CONFIG_DEBUG_INFO_SPLIT
855
DEBUG_CFLAGS	+= -gsplit-dwarf
A
Andi Kleen 已提交
856
else
857
DEBUG_CFLAGS	+= -g
A
Andi Kleen 已提交
858
endif
859

860
ifneq ($(LLVM_IAS),1)
861
KBUILD_AFLAGS	+= -Wa,-gdwarf-2
862
endif
863

864 865
ifndef CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT
dwarf-version-$(CONFIG_DEBUG_INFO_DWARF4) := 4
866
dwarf-version-$(CONFIG_DEBUG_INFO_DWARF5) := 5
867
DEBUG_CFLAGS	+= -gdwarf-$(dwarf-version-y)
868
endif
L
Linus Torvalds 已提交
869

870
ifdef CONFIG_DEBUG_INFO_REDUCED
871
DEBUG_CFLAGS	+= $(call cc-option, -femit-struct-debug-baseonly) \
872
		   $(call cc-option,-fno-var-tracking)
873 874
endif

875 876
ifdef CONFIG_DEBUG_INFO_COMPRESSED
DEBUG_CFLAGS	+= -gz=zlib
877
KBUILD_AFLAGS	+= -gz=zlib
878 879 880
KBUILD_LDFLAGS	+= --compress-debug-sections=zlib
endif

881 882
endif # CONFIG_DEBUG_INFO

883 884 885
KBUILD_CFLAGS += $(DEBUG_CFLAGS)
export DEBUG_CFLAGS

886
ifdef CONFIG_FUNCTION_TRACER
887 888
ifdef CONFIG_FTRACE_MCOUNT_USE_CC
  CC_FLAGS_FTRACE	+= -mrecord-mcount
889 890 891 892 893 894
  ifdef CONFIG_HAVE_NOP_MCOUNT
    ifeq ($(call cc-option-yn, -mnop-mcount),y)
      CC_FLAGS_FTRACE	+= -mnop-mcount
      CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
    endif
  endif
895
endif
896 897 898
ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
  CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
endif
899 900 901 902 903 904
ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
  ifdef CONFIG_HAVE_C_RECORDMCOUNT
    BUILD_C_RECORDMCOUNT := y
    export BUILD_C_RECORDMCOUNT
  endif
endif
905
ifdef CONFIG_HAVE_FENTRY
906 907 908 909
  ifeq ($(call cc-option-yn, -mfentry),y)
    CC_FLAGS_FTRACE	+= -mfentry
    CC_FLAGS_USING	+= -DCC_USING_FENTRY
  endif
910
endif
911 912 913
export CC_FLAGS_FTRACE
KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
914 915
endif

916 917 918 919 920
# We trigger additional mismatches with less inlining
ifdef CONFIG_DEBUG_SECTION_MISMATCH
KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
endif

921
ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
922 923
KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
LDFLAGS_vmlinux += --gc-sections
924 925
endif

926 927 928 929 930 931
ifdef CONFIG_SHADOW_CALL_STACK
CC_FLAGS_SCS	:= -fsanitize=shadow-call-stack
KBUILD_CFLAGS	+= $(CC_FLAGS_SCS)
export CC_FLAGS_SCS
endif

932 933
ifdef CONFIG_LTO_CLANG
ifdef CONFIG_LTO_CLANG_THIN
934
CC_FLAGS_LTO	:= -flto=thin -fsplit-lto-unit
935
KBUILD_LDFLAGS	+= --thinlto-cache-dir=$(extmod_prefix).thinlto-cache
936
else
937
CC_FLAGS_LTO	:= -flto
938 939
endif
CC_FLAGS_LTO	+= -fvisibility=hidden
S
Sami Tolvanen 已提交
940 941 942

# Limit inlining across translation units to reduce binary size
KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
943

944 945
# Check for frame size exceeding threshold during prolog/epilog insertion
# when using lld < 13.0.0.
946
ifneq ($(CONFIG_FRAME_WARN),0)
947
ifeq ($(shell test $(CONFIG_LLD_VERSION) -lt 130000; echo $$?),0)
948 949
KBUILD_LDFLAGS	+= -plugin-opt=-warn-stack-size=$(CONFIG_FRAME_WARN)
endif
950
endif
951
endif
952 953

ifdef CONFIG_LTO
954 955
KBUILD_CFLAGS	+= -fno-lto $(CC_FLAGS_LTO)
KBUILD_AFLAGS	+= -fno-lto
956 957 958
export CC_FLAGS_LTO
endif

S
Sami Tolvanen 已提交
959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975
ifdef CONFIG_CFI_CLANG
CC_FLAGS_CFI	:= -fsanitize=cfi \
		   -fsanitize-cfi-cross-dso \
		   -fno-sanitize-cfi-canonical-jump-tables \
		   -fno-sanitize-trap=cfi \
		   -fno-sanitize-blacklist

ifdef CONFIG_CFI_PERMISSIVE
CC_FLAGS_CFI	+= -fsanitize-recover=cfi
endif

# If LTO flags are filtered out, we must also filter out CFI.
CC_FLAGS_LTO	+= $(CC_FLAGS_CFI)
KBUILD_CFLAGS	+= $(CC_FLAGS_CFI)
export CC_FLAGS_CFI
endif

976 977
ifdef CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_64B
KBUILD_CFLAGS += -falign-functions=64
978 979
endif

980
# arch Makefile may override CC so keep this after arch Makefile is included
M
Masahiro Yamada 已提交
981
NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
982

L
Linus Torvalds 已提交
983
# warn about C99 declaration after statement
984
KBUILD_CFLAGS += -Wdeclaration-after-statement
L
Linus Torvalds 已提交
985

K
Kees Cook 已提交
986
# Variable Length Arrays (VLAs) should not be used anywhere in the kernel
987
KBUILD_CFLAGS += -Wvla
K
Kees Cook 已提交
988

S
Sam Ravnborg 已提交
989
# disable pointer signed / unsigned warnings in gcc 4.0
990
KBUILD_CFLAGS += -Wno-pointer-sign
L
Linus Torvalds 已提交
991

992 993 994
# disable stringop warnings in gcc 8+
KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)

995 996
# We'll want to enable this eventually, but it's not going away for 5.7 at least
KBUILD_CFLAGS += $(call cc-disable-warning, zero-length-bounds)
997
KBUILD_CFLAGS += $(call cc-disable-warning, array-bounds)
998
KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
999

1000 1001 1002
# Another good warning that we'll want to enable eventually
KBUILD_CFLAGS += $(call cc-disable-warning, restrict)

1003 1004 1005
# Enabled with W=2, disabled by default as noisy
KBUILD_CFLAGS += $(call cc-disable-warning, maybe-uninitialized)

1006
# disable invalid "can't wrap" optimizations for signed / pointers
1007
KBUILD_CFLAGS	+= -fno-strict-overflow
1008

1009
# Make sure -fstack-check isn't enabled (like gentoo apparently did)
1010
KBUILD_CFLAGS  += -fno-stack-check
1011

1012 1013 1014
# conserve stack if available
KBUILD_CFLAGS   += $(call cc-option,-fconserve-stack)

1015
# Prohibit date/time macros, which would make the build non-deterministic
1016
KBUILD_CFLAGS   += -Werror=date-time
1017

1018 1019 1020
# enforce correct pointer usage
KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)

1021 1022 1023
# Require designated initializers for all marked structures
KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)

1024
# change __FILE__ to the relative path from the srctree
1025
KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
1026

1027 1028 1029 1030 1031 1032 1033 1034 1035
# include additional Makefiles when needed
include-y			:= scripts/Makefile.extrawarn
include-$(CONFIG_KASAN)		+= scripts/Makefile.kasan
include-$(CONFIG_KCSAN)		+= scripts/Makefile.kcsan
include-$(CONFIG_UBSAN)		+= scripts/Makefile.ubsan
include-$(CONFIG_KCOV)		+= scripts/Makefile.kcov
include-$(CONFIG_GCC_PLUGINS)	+= scripts/Makefile.gcc-plugins

include $(addprefix $(srctree)/, $(include-y))
1036

1037 1038 1039
# 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.
1040

1041 1042 1043 1044
# Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
KBUILD_CPPFLAGS += $(KCPPFLAGS)
KBUILD_AFLAGS   += $(KAFLAGS)
KBUILD_CFLAGS   += $(KCFLAGS)
1045

1046 1047
KBUILD_LDFLAGS_MODULE += --build-id=sha1
LDFLAGS_vmlinux += --build-id=sha1
R
Roland McGrath 已提交
1048

1049
ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1050
LDFLAGS_vmlinux	+= $(call ld-option, -X,)
1051 1052
endif

1053
ifeq ($(CONFIG_RELR),y)
1054
LDFLAGS_vmlinux	+= --pack-dyn-relocs=relr --use-android-relr-tags
1055 1056
endif

1057 1058 1059 1060 1061 1062
# 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=warn
endif

1063
# Align the bit size of userspace programs with the kernel
1064 1065
KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1066

1067 1068 1069
# make the checker run with the right architecture
CHECKFLAGS += --arch=$(ARCH)

1070 1071 1072
# insure the checker run with the right endianness
CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)

1073 1074 1075
# the checker needs the correct machine size
CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)

L
Linus Torvalds 已提交
1076
# Default kernel image to build when no specific target is given.
S
Sam Ravnborg 已提交
1077
# KBUILD_IMAGE may be overruled on the command line or
L
Linus Torvalds 已提交
1078 1079 1080 1081 1082 1083 1084 1085 1086 1087
# 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

1088 1089 1090 1091 1092 1093 1094
#
# 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)

L
Linus Torvalds 已提交
1095 1096 1097
#
# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
# relocations required by build roots.  This is not defined in the
S
Sam Ravnborg 已提交
1098
# makefile but the argument can be passed to make if needed.
L
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1099 1100
#

1101
MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
L
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1102 1103
export MODLIB

1104
PHONY += prepare0
1105

1106
export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
1107 1108
export MODORDER := $(extmod_prefix)modules.order
export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
1109

L
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1110
ifeq ($(KBUILD_EXTMOD),)
1111
core-y		+= kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
L
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1112

1113
vmlinux-dirs	:= $(patsubst %/,%,$(filter %/, \
L
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1114
		     $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
1115
		     $(libs-y) $(libs-m)))
L
Linus Torvalds 已提交
1116

1117
vmlinux-alldirs	:= $(sort $(vmlinux-dirs) Documentation \
1118
		     $(patsubst %/,%,$(filter %/, $(core-) \
1119
			$(drivers-) $(libs-))))
L
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1120

1121 1122 1123
subdir-modorder := $(addsuffix modules.order,$(filter %/, \
			$(core-y) $(core-m) $(libs-y) $(libs-m) \
			$(drivers-y) $(drivers-m)))
L
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1124

1125
build-dirs	:= $(vmlinux-dirs)
1126
clean-dirs	:= $(vmlinux-alldirs)
1127

1128 1129 1130
# Externally visible symbols (used by link-vmlinux.sh)
KBUILD_VMLINUX_OBJS := $(head-y) $(patsubst %/,%/built-in.a, $(core-y))
KBUILD_VMLINUX_OBJS += $(addsuffix built-in.a, $(filter %/, $(libs-y)))
1131
ifdef CONFIG_MODULES
1132 1133
KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1134
else
1135
KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1136
endif
1137
KBUILD_VMLINUX_OBJS += $(patsubst %/,%/built-in.a, $(drivers-y))
L
Linus Torvalds 已提交
1138

1139
export KBUILD_VMLINUX_OBJS KBUILD_VMLINUX_LIBS
1140
export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1141
# used by scripts/Makefile.package
1142
export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) LICENSES arch include scripts tools)
1143

1144
vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
L
Linus Torvalds 已提交
1145

1146 1147
# Recurse until adjust_autoksyms.sh is satisfied
PHONY += autoksyms_recursive
1148
ifdef CONFIG_TRIM_UNUSED_KSYMS
1149 1150 1151
# For the kernel to actually contain only the needed exported symbols,
# we have to build modules as well to determine what those symbols are.
# (this can be evaluated only once include/config/auto.conf has been included)
1152 1153 1154 1155 1156
KBUILD_MODULES := 1

autoksyms_recursive: descend modules.order
	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
	  "$(MAKE) -f $(srctree)/Makefile vmlinux"
1157 1158
endif

1159 1160
autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)

1161 1162 1163 1164
quiet_cmd_autoksyms_h = GEN     $@
      cmd_autoksyms_h = mkdir -p $(dir $@); \
			$(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@

1165
$(autoksyms_h):
1166
	$(call cmd,autoksyms_h)
1167

1168 1169 1170
ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)

# Final link of vmlinux with optional arch pass after final link
1171
cmd_link-vmlinux =                                                 \
1172
	$(CONFIG_SHELL) $< "$(LD)" "$(KBUILD_LDFLAGS)" "$(LDFLAGS_vmlinux)";    \
1173
	$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1174

1175
vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1176
	+$(call if_changed_dep,link-vmlinux)
1177

1178 1179
targets := vmlinux

1180
# The actual objects are generated when descending,
L
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1181
# make sure no implicit rule kicks in
1182
$(sort $(vmlinux-deps) $(subdir-modorder)): descend ;
L
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1183

1184
filechk_kernel.release = \
1185 1186
	echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"

G
Geert Uytterhoeven 已提交
1187
# Store (new) KERNELRELEASE string in include/config/kernel.release
1188
include/config/kernel.release: FORCE
1189
	$(call filechk,kernel.release)
1190

1191 1192 1193 1194
# Additional helpers built in scripts/
# Carefully list dependencies so we do not try to build scripts twice
# in parallel
PHONY += scripts
1195
scripts: scripts_basic scripts_dtc
1196
	$(Q)$(MAKE) $(build)=$(@)
1197

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# Things we need to do before we recursively start building the kernel
1199 1200 1201 1202
# 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.
L
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1203

M
Masahiro Yamada 已提交
1204
PHONY += prepare archprepare
1205

1206
archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1207
	asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h \
1208
	include/generated/autoconf.h remove-stale-files
1209

1210
prepare0: archprepare
1211
	$(Q)$(MAKE) $(build)=scripts/mod
1212
	$(Q)$(MAKE) $(build)=.
1213

L
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1214
# All the preparing..
1215
prepare: prepare0
1216

1217 1218 1219 1220
PHONY += remove-stale-files
remove-stale-files:
	$(Q)$(srctree)/scripts/remove-stale-files

1221
# Support for using generic headers in asm-generic
1222 1223
asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj

1224 1225
PHONY += asm-generic uapi-asm-generic
asm-generic: uapi-asm-generic
1226 1227
	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
	generic=include/asm-generic
1228
uapi-asm-generic:
1229 1230
	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
	generic=include/uapi/asm-generic
1231

L
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1232 1233 1234 1235 1236 1237 1238
# 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
S
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1239 1240 1241 1242 1243
define filechk_utsrelease.h
	if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
	  exit 1;                                                         \
	fi;                                                               \
1244
	echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
S
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1245
endef
L
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1246 1247

define filechk_version.h
S
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1248 1249
	if [ $(SUBLEVEL) -gt 255 ]; then                                 \
		echo \#define LINUX_VERSION_CODE $(shell                 \
1250
		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
S
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1251 1252
	else                                                             \
		echo \#define LINUX_VERSION_CODE $(shell                 \
1253
		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
S
Sasha Levin 已提交
1254 1255
	fi;                                                              \
	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
1256 1257 1258 1259
	((c) > 255 ? 255 : (c)))';                                       \
	echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
	echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
	echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
L
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1260 1261
endef

1262 1263
$(version_h): PATCHLEVEL := $(if $(PATCHLEVEL), $(PATCHLEVEL), 0)
$(version_h): SUBLEVEL := $(if $(SUBLEVEL), $(SUBLEVEL), 0)
1264
$(version_h): FORCE
L
Linus Torvalds 已提交
1265 1266
	$(call filechk,version.h)

1267
include/generated/utsrelease.h: include/config/kernel.release FORCE
S
Sam Ravnborg 已提交
1268 1269
	$(call filechk,utsrelease.h)

1270 1271
PHONY += headerdep
headerdep:
1272 1273
	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
	$(srctree)/scripts/headerdep.pl -I$(srctree)/include
1274

1275 1276 1277
# ---------------------------------------------------------------------------
# Kernel headers

1278 1279
#Default location for installed headers
export INSTALL_HDR_PATH = $(objtree)/usr
1280

1281 1282 1283 1284 1285
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)
1286

1287
PHONY += headers_install
1288 1289
headers_install: headers
	$(call cmd,headers_install)
1290

1291
PHONY += archheaders archscripts
1292

1293
hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1294

1295 1296
PHONY += headers
headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1297
	$(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1298
	  $(error Headers not exportable for the $(SRCARCH) architecture))
1299 1300
	$(Q)$(MAKE) $(hdr-inst)=include/uapi
	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1301

1302
# Deprecated. It is no-op now.
1303
PHONY += headers_check
1304
headers_check:
1305 1306 1307 1308 1309
	@echo >&2 "=================== WARNING ==================="
	@echo >&2 "Since Linux 5.5, 'make headers_check' is no-op,"
	@echo >&2 "and will be removed after Linux 5.15 release."
	@echo >&2 "Please remove headers_check from your scripts."
	@echo >&2 "==============================================="
1310

1311
ifdef CONFIG_HEADERS_INSTALL
1312
prepare: headers
1313
endif
1314

1315 1316 1317 1318
PHONY += scripts_unifdef
scripts_unifdef: scripts_basic
	$(Q)$(MAKE) $(build)=scripts scripts/unifdef

1319 1320 1321 1322 1323 1324 1325 1326 1327 1328
# ---------------------------------------------------------------------------
# Install

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

install: sub_make_done :=

1329 1330 1331
# ---------------------------------------------------------------------------
# Tools

1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352
ifdef CONFIG_STACK_VALIDATION
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

1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365
# 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/ $*

1366 1367 1368 1369 1370
# ---------------------------------------------------------------------------
# Kernel selftest

PHONY += kselftest
kselftest:
1371
	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1372

1373 1374
kselftest-%: FORCE
	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
W
Wang Long 已提交
1375

1376 1377 1378
PHONY += kselftest-merge
kselftest-merge:
	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1379 1380
	$(Q)find $(srctree)/tools/testing/selftests -name config | \
		xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1381
	$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1382

1383 1384 1385 1386 1387 1388 1389 1390 1391
# ---------------------------------------------------------------------------
# Devicetree files

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

ifneq ($(dtstree),)

M
Masahiro Yamada 已提交
1392
%.dtb: include/config/kernel.release scripts_dtc
1393 1394
	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@

1395 1396 1397
%.dtbo: include/config/kernel.release scripts_dtc
	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@

1398
PHONY += dtbs dtbs_install dtbs_check
1399
dtbs: include/config/kernel.release scripts_dtc
1400 1401
	$(Q)$(MAKE) $(build)=$(dtstree)

1402
ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1403
export CHECK_DTBS=y
1404 1405 1406 1407
dtbs: dt_binding_check
endif

dtbs_check: dtbs
1408

1409
dtbs_install:
1410
	$(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421

ifdef CONFIG_OF_EARLY_FLATTREE
all: dtbs
endif

endif

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

1422 1423 1424 1425
ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
export CHECK_DT_BINDING=y
endif

1426
PHONY += dt_binding_check
1427 1428 1429
dt_binding_check: scripts_dtc
	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings

L
Linus Torvalds 已提交
1430 1431 1432 1433 1434
# ---------------------------------------------------------------------------
# Modules

ifdef CONFIG_MODULES

S
Sam Ravnborg 已提交
1435
# By default, build modules as well
L
Linus Torvalds 已提交
1436

1437
all: modules
L
Linus Torvalds 已提交
1438

1439 1440 1441 1442 1443 1444 1445
# 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

1446
# Build modules
T
Tejun Heo 已提交
1447
#
1448 1449 1450
# A module can be listed more than once in obj-m resulting in
# duplicate lines in modules.order files.  Those are removed
# using awk while concatenating to the final file.
L
Linus Torvalds 已提交
1451

1452
PHONY += modules
1453
modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_check modules_prepare
L
Linus Torvalds 已提交
1454

1455 1456 1457 1458 1459 1460
cmd_modules_order = $(AWK) '!x[$$0]++' $(real-prereqs) > $@

modules.order: $(subdir-modorder) FORCE
	$(call if_changed,modules_order)

targets += modules.order
1461

L
Linus Torvalds 已提交
1462
# Target to prepare building external modules
1463
PHONY += modules_prepare
1464
modules_prepare: prepare
1465
	$(Q)$(MAKE) $(build)=scripts scripts/module.lds
L
Linus Torvalds 已提交
1466

1467 1468 1469 1470 1471 1472
export modules_sign_only :=

ifeq ($(CONFIG_MODULE_SIG),y)
PHONY += modules_sign
modules_sign: modules_install
	@:
L
Linus Torvalds 已提交
1473

1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486
# 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

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

modules_install: $(modinst_pre)
1487 1488
PHONY += __modinst_pre
__modinst_pre:
L
Linus Torvalds 已提交
1489 1490 1491
	@rm -rf $(MODLIB)/kernel
	@rm -f $(MODLIB)/source
	@mkdir -p $(MODLIB)/kernel
1492
	@ln -s $(abspath $(srctree)) $(MODLIB)/source
L
Linus Torvalds 已提交
1493 1494
	@if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
		rm -f $(MODLIB)/build ; \
1495
		ln -s $(CURDIR) $(MODLIB)/build ; \
L
Linus Torvalds 已提交
1496
	fi
1497
	@sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order
1498 1499
	@cp -f modules.builtin $(MODLIB)/
	@cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
L
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1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510

endif # CONFIG_MODULES

###
# 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'
1511
CLEAN_FILES += include/ksym vmlinux.symvers modules-only.symvers \
1512
	       modules.builtin modules.builtin.modinfo modules.nsdeps \
1513
	       compile_commands.json .thinlto-cache
L
Linus Torvalds 已提交
1514 1515

# Directories & files removed with 'make mrproper'
1516
MRPROPER_FILES += include/config include/generated          \
1517
		  arch/$(SRCARCH)/include/generated .tmp_objdiff \
1518 1519
		  debian snap tar-install \
		  .config .config.old .version \
1520
		  Module.symvers \
1521 1522 1523
		  certs/signing_key.pem certs/signing_key.x509 \
		  certs/x509.genkey \
		  vmlinux-gdb.py \
1524
		  *.spec
L
Linus Torvalds 已提交
1525 1526 1527 1528 1529

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

1530
PHONY += archclean vmlinuxclean
L
Linus Torvalds 已提交
1531

1532 1533
vmlinuxclean:
	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1534
	$(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1535

1536
clean: archclean vmlinuxclean resolve_btfids_clean
L
Linus Torvalds 已提交
1537 1538 1539 1540

# mrproper - Delete all generated files, including .config
#
mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1541
mrproper-dirs      := $(addprefix _mrproper_,scripts)
L
Linus Torvalds 已提交
1542

1543
PHONY += $(mrproper-dirs) mrproper
L
Linus Torvalds 已提交
1544 1545 1546
$(mrproper-dirs):
	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)

1547
mrproper: clean $(mrproper-dirs)
L
Linus Torvalds 已提交
1548 1549 1550 1551
	$(call cmd,rmfiles)

# distclean
#
1552
PHONY += distclean
L
Linus Torvalds 已提交
1553 1554

distclean: mrproper
1555
	@find . $(RCS_FIND_IGNORE) \
S
Sam Ravnborg 已提交
1556
		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1557
		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
1558 1559
		-o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
		-o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
L
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1560 1561 1562 1563 1564 1565
		-type f -print | xargs rm -f


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

1566
%src-pkg: FORCE
1567
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1568
%pkg: include/config/kernel.release FORCE
1569
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
L
Linus Torvalds 已提交
1570 1571 1572 1573

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

1574
boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1575
boards := $(sort $(notdir $(boards)))
1576 1577
board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
board-dirs := $(sort $(notdir $(board-dirs:/=)))
L
Linus Torvalds 已提交
1578

1579
PHONY += help
L
Linus Torvalds 已提交
1580 1581
help:
	@echo  'Cleaning targets:'
1582
	@echo  '  clean		  - Remove most generated files but keep the config and'
1583
	@echo  '                    enough build support to build external modules'
1584
	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
1585
	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
L
Linus Torvalds 已提交
1586 1587 1588 1589 1590 1591 1592 1593
	@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'
1594
	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
L
Linus Torvalds 已提交
1595
	@echo  '  dir/            - Build all files in dir and below'
1596
	@echo  '  dir/file.[ois]  - Build specified target only'
1597 1598
	@echo  '  dir/file.ll     - Build the LLVM assembly file'
	@echo  '                    (requires compiler support for LLVM assembly generation)'
1599 1600
	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
	@echo  '                    (requires a recent binutils and recent build (System.map))'
1601
	@echo  '  dir/file.ko     - Build module including final link'
1602
	@echo  '  modules_prepare - Set up for building external modules'
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	@echo  '  tags/TAGS	  - Generate tags file for editors'
	@echo  '  cscope	  - Generate cscope index'
1605
	@echo  '  gtags           - Generate GNU GLOBAL index'
1606 1607 1608
	@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)'
1609
	@echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1610
	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1611
	 echo  ''
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	@echo  'Static analysers:'
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	@echo  '  checkstack      - Generate a list of stack hogs'
1614
	@echo  '  versioncheck    - Sanity check on version.h usage'
1615
	@echo  '  includecheck    - Check for duplicate included header files'
1616
	@echo  '  export_report   - List the usages of all exported symbols'
1617
	@echo  '  headerdep       - Detect inclusion cycles in headers'
1618
	@echo  '  coccicheck      - Check with Coccinelle'
1619 1620
	@echo  '  clang-analyzer  - Check with clang static analyzer'
	@echo  '  clang-tidy      - Check with clang-tidy'
1621
	@echo  ''
1622 1623 1624
	@echo  'Tools:'
	@echo  '  nsdeps          - Generate missing symbol namespace dependencies'
	@echo  ''
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1625
	@echo  'Kernel selftest:'
1626 1627 1628 1629 1630 1631 1632 1633 1634
	@echo  '  kselftest         - Build and run kernel selftest'
	@echo  '                      Build, install, and boot kernel before'
	@echo  '                      running kselftest on it'
	@echo  '                      Run as root for full coverage'
	@echo  '  kselftest-all     - Build kernel selftest'
	@echo  '  kselftest-install - Build and install kernel selftest'
	@echo  '  kselftest-clean   - Remove all generated kselftest files'
	@echo  '  kselftest-merge   - Merge all the config dependencies of'
	@echo  '		      kselftest to existing .config.'
1635
	@echo  ''
1636 1637
	@$(if $(dtstree), \
		echo 'Devicetree:'; \
1638 1639 1640 1641
		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';\
1642 1643
		echo '')

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	@echo 'Userspace tools targets:'
	@echo '  use "make tools/help"'
	@echo '  or  "cd tools; make help"'
	@echo  ''
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1648
	@echo  'Kernel packaging:'
1649
	@$(MAKE) -f $(srctree)/scripts/Makefile.package help
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1650 1651
	@echo  ''
	@echo  'Documentation targets:'
1652
	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
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1653
	@echo  ''
1654
	@echo  'Architecture specific targets ($(SRCARCH)):'
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1655
	@$(if $(archhelp),$(archhelp),\
1656
		echo '  No architecture specific help defined for $(SRCARCH)')
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1657 1658 1659
	@echo  ''
	@$(if $(boards), \
		$(foreach b, $(boards), \
1660
		printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
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1661
		echo '')
1662 1663 1664 1665 1666
	@$(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 '')
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1667 1668

	@echo  '  make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1669
	@echo  '  make V=2   [targets] 2 => give reason for rebuild of target'
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1670
	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1671 1672
	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
	@echo  '                       (sparse by default)'
1673
	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1674
	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1675
	@echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
1676 1677 1678
	@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'
1679
	@echo  '		Multiple levels can be combined with W=12 or W=123'
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1680 1681 1682 1683 1684
	@echo  ''
	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
	@echo  'For further info see the ./README file'


1685 1686 1687 1688
help-board-dirs := $(addprefix help-,$(board-dirs))

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

1689
boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1690 1691 1692 1693 1694 1695 1696 1697 1698

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


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1699 1700
# Documentation targets
# ---------------------------------------------------------------------------
1701 1702
DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
	       linkcheckdocs dochelp refcheckdocs
1703
PHONY += $(DOC_TARGETS)
1704
$(DOC_TARGETS):
1705
	$(Q)$(MAKE) $(build)=Documentation $@
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1706

1707 1708 1709 1710
# Misc
# ---------------------------------------------------------------------------

PHONY += scripts_gdb
1711
scripts_gdb: prepare0
1712
	$(Q)$(MAKE) $(build)=scripts/gdb
1713
	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1714 1715 1716 1717 1718

ifdef CONFIG_GDB_SCRIPTS
all: scripts_gdb
endif

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1719 1720 1721 1722 1723 1724 1725
else # KBUILD_EXTMOD

###
# 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
1726
# in the basis kernel ordinary make commands (without M=...) must be used.
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1727

1728 1729
# We are always building only modules.
KBUILD_BUILTIN :=
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KBUILD_MODULES := 1

1732
build-dirs := $(KBUILD_EXTMOD)
1733 1734 1735
$(MODORDER): descend
	@:

1736
compile_commands.json: $(extmod_prefix)compile_commands.json
1737 1738
PHONY += compile_commands.json

1739
clean-dirs := $(KBUILD_EXTMOD)
1740
clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1741
	$(KBUILD_EXTMOD)/compile_commands.json $(KBUILD_EXTMOD)/.thinlto-cache
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1742

1743
PHONY += help
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1744 1745 1746 1747 1748 1749 1750 1751
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  ''
1752

1753 1754 1755
# no-op for external module builds
PHONY += prepare modules_prepare

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endif # KBUILD_EXTMOD

1758 1759 1760 1761 1762 1763 1764
# ---------------------------------------------------------------------------
# Modules

PHONY += modules modules_install

ifdef CONFIG_MODULES

1765
modules: modules_check
1766 1767
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost

1768 1769 1770 1771
PHONY += modules_check
modules_check: $(MODORDER)
	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<

1772
quiet_cmd_depmod = DEPMOD  $(MODLIB)
1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794
      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
# ---------------------------------------------------------------------------

modules modules_install:
	@echo >&2 '***'
	@echo >&2 '*** The present kernel configuration has modules disabled.'
	@echo >&2 '*** To use the module feature, please run "make menuconfig" etc.'
	@echo >&2 '*** to enable CONFIG_MODULES.'
	@echo >&2 '***'
	@exit 1

endif # CONFIG_MODULES

1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824
# 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
single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
single-no-ko := $(sort $(patsubst %.ko,%.mod, $(MAKECMDGOALS)))

$(single-ko): single_modpost
	@:
$(single-no-ko): descend
	@:

ifeq ($(KBUILD_EXTMOD),)
# For the single build of in-tree modules, use a temporary file to avoid
# the situation of modules_install installing an invalid modules.order.
MODORDER := .modules.tmp
endif

PHONY += single_modpost
1825
single_modpost: $(single-no-ko) modules_prepare
1826
	$(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$m;) } > $(MODORDER)
1827 1828 1829 1830
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost

KBUILD_MODULES := 1

1831
export KBUILD_SINGLE_TARGETS := $(addprefix $(extmod_prefix), $(single-no-ko))
1832 1833 1834 1835 1836 1837 1838

# trim unrelated directories
build-dirs := $(foreach d, $(build-dirs), \
			$(if $(filter $(d)/%, $(KBUILD_SINGLE_TARGETS)), $(d)))

endif

1839 1840 1841 1842
ifndef CONFIG_MODULES
KBUILD_MODULES :=
endif

1843 1844 1845 1846 1847 1848 1849 1850
# Handle descending into subdirectories listed in $(build-dirs)
# Preset locale variables to speed up the build process. Limit locale
# tweaks to this spot to avoid wrong language settings when running
# make menuconfig etc.
# Error messages still appears in the original language
PHONY += descend $(build-dirs)
descend: $(build-dirs)
$(build-dirs): prepare
1851
	$(Q)$(MAKE) $(build)=$@ \
1852
	single-build=$(if $(filter-out $@/, $(filter $@/%, $(KBUILD_SINGLE_TARGETS))),1) \
1853
	need-builtin=1 need-modorder=1
1854

1855 1856 1857 1858 1859
clean-dirs := $(addprefix _clean_, $(clean-dirs))
PHONY += $(clean-dirs) clean
$(clean-dirs):
	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)

1860 1861
clean: $(clean-dirs)
	$(call cmd,rmfiles)
1862
	@find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1863
		\( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1864
		-o -name '*.ko.*' \
1865
		-o -name '*.dtb' -o -name '*.dtbo' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1866
		-o -name '*.dwo' -o -name '*.lst' \
1867
		-o -name '*.su' -o -name '*.mod' \
1868
		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1869
		-o -name '*.lex.c' -o -name '*.tab.[ch]' \
1870
		-o -name '*.asn1.[ch]' \
1871
		-o -name '*.symtypes' -o -name 'modules.order' \
1872
		-o -name '.tmp_*.o.*' \
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		-o -name '*.c.[012]*.*' \
1874
		-o -name '*.ll' \
1875 1876
		-o -name '*.gcno' \
		-o -name '*.*.symversions' \) -type f -print | xargs rm -f
1877

L
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1878 1879
# Generate tags for editors
# ---------------------------------------------------------------------------
1880
quiet_cmd_tags = GEN     $@
1881
      cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
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1882

1883
tags TAGS cscope gtags: FORCE
L
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1884 1885
	$(call cmd,tags)

1886 1887 1888 1889
# Script to generate missing namespace dependencies
# ---------------------------------------------------------------------------

PHONY += nsdeps
1890
nsdeps: export KBUILD_NSDEPS=1
1891
nsdeps: modules
1892
	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1893

1894 1895 1896 1897 1898 1899
# Clang Tooling
# ---------------------------------------------------------------------------

quiet_cmd_gen_compile_commands = GEN     $@
      cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))

1900
$(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
1901 1902 1903 1904
	$(if $(KBUILD_EXTMOD),,$(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)) \
	$(if $(CONFIG_MODULES), $(MODORDER)) FORCE
	$(call if_changed,gen_compile_commands)

1905
targets += $(extmod_prefix)compile_commands.json
1906

1907 1908 1909 1910 1911 1912
PHONY += clang-tidy clang-analyzer

ifdef CONFIG_CC_IS_CLANG
quiet_cmd_clang_tools = CHECK   $<
      cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<

1913
clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
1914 1915 1916 1917 1918 1919 1920
	$(call cmd,clang_tools)
else
clang-tidy clang-analyzer:
	@echo "$@ requires CC=clang" >&2
	@false
endif

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1921 1922 1923
# Scripts to check various things for consistency
# ---------------------------------------------------------------------------

J
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1924
PHONY += includecheck versioncheck coccicheck export_report
P
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1925

L
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1926
includecheck:
1927
	find $(srctree)/* $(RCS_FIND_IGNORE) \
L
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1928
		-name '*.[hcS]' -type f -print | sort \
1929
		| xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
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1930 1931

versioncheck:
1932
	find $(srctree)/* $(RCS_FIND_IGNORE) \
L
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1933
		-name '*.[hcS]' -type f -print | sort \
1934
		| xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
L
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1935

1936
coccicheck:
1937
	$(Q)$(BASH) $(srctree)/scripts/$@
1938

1939 1940 1941
export_report:
	$(PERL) $(srctree)/scripts/export_report.pl

1942
PHONY += checkstack kernelrelease kernelversion image_name
J
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1943

J
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1944 1945 1946 1947 1948 1949 1950 1951 1952
# UML needs a little special treatment here.  It wants to use the host
# toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
# else wants $(ARCH), including people doing cross-builds, which means
# that $(SUBARCH) doesn't work here.
ifeq ($(ARCH), um)
CHECKSTACK_ARCH := $(SUBARCH)
else
CHECKSTACK_ARCH := $(ARCH)
endif
L
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1953 1954
checkstack:
	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1955
	$(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
L
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1956

1957 1958
kernelrelease:
	@echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1959

1960
kernelversion:
1961
	@echo $(KERNELVERSION)
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1962

1963 1964 1965
image_name:
	@echo $(KBUILD_IMAGE)

L
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quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
1967
      cmd_rmfiles = rm -rf $(rm-files)
L
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1968

1969 1970
# read saved command lines for existing targets
existing-targets := $(wildcard $(sort $(targets)))
L
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1971

1972
-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
L
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1973

1974
endif # config-build
1975 1976
endif # mixed-build
endif # need-sub-make
L
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1977

1978
PHONY += FORCE
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1979
FORCE:
1980

1981
# Declare the contents of the PHONY variable as phony.  We keep that
1982
# information in a variable so we can use it in if_changed and friends.
1983
.PHONY: $(PHONY)