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# SPDX-License-Identifier: GPL-2.0
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VERSION = 5
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PATCHLEVEL = 15
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SUBLEVEL = 0
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EXTRAVERSION = -rc6
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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
#
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# --included-dir is added for backward compatibility, but you should not rely on
# it. Please add $(srctree)/ prefix to include Makefiles in the source tree.
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MAKEFLAGS += --include-dir=$(abs_srctree)
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 ($(ARCH),sparc64)
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       SRCARCH := sparc
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endif
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# Additional ARCH settings for parisc
ifeq ($(ARCH),parisc64)
       SRCARCH := parisc
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)
581 582
	$(Q)test -e .gitignore || \
	{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
583
endif
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585 586 587 588
# The expansion should be delayed until arch/$(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.
589
CC_VERSION_TEXT = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1))
590 591

ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
592
include $(srctree)/scripts/Makefile.clang
593 594
endif

595 596
# Include this also for config targets because some architectures need
# cc-cross-prefix to determine CROSS_COMPILE.
597
ifdef need-compiler
598
include $(srctree)/scripts/Makefile.compiler
599
endif
600

601
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'
609
include $(srctree)/arch/$(SRCARCH)/Makefile
610
export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
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612
config: outputmakefile scripts_basic FORCE
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613 614
	$(Q)$(MAKE) $(build)=scripts/kconfig $@

615
%config: outputmakefile scripts_basic FORCE
L
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616 617
	$(Q)$(MAKE) $(build)=scripts/kconfig $@

618
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.

623
# If building an external module we do not care about the all: rule
624
# but instead __all depend on modules
625 626
PHONY += all
ifeq ($(KBUILD_EXTMOD),)
627
__all: all
628
else
629
__all: modules
630 631 632 633 634 635 636 637 638 639
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)
640
  KBUILD_BUILTIN :=
641 642 643 644 645 646
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

647
ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
648 649 650 651 652 653 654 655 656
  KBUILD_MODULES := 1
endif

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

export KBUILD_MODULES KBUILD_BUILTIN

657
ifdef need-config
658 659 660
include include/config/auto.conf
endif

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ifeq ($(KBUILD_EXTMOD),)
# Objects we will link into vmlinux / subdirs we need to visit
663
core-y		:= init/ usr/ arch/$(SRCARCH)/
664
drivers-y	:= drivers/ sound/
665
drivers-$(CONFIG_SAMPLES) += samples/
666 667
drivers-$(CONFIG_NET) += net/
drivers-y	+= virt/
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668 669 670
libs-y		:= lib/
endif # KBUILD_EXTMOD

671 672 673 674 675 676
# 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

677 678 679 680
CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage
ifdef CONFIG_CC_IS_GCC
CFLAGS_GCOV	+= -fno-tree-loop-im
endif
681
export CFLAGS_GCOV
682

683 684 685 686 687
# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
ifdef CONFIG_FUNCTION_TRACER
  CC_FLAGS_FTRACE := -pg
endif

688 689 690 691 692 693 694 695
ifdef CONFIG_CC_IS_GCC
RETPOLINE_CFLAGS	:= $(call cc-option,-mindirect-branch=thunk-extern -mindirect-branch-register)
RETPOLINE_VDSO_CFLAGS	:= $(call cc-option,-mindirect-branch=thunk-inline -mindirect-branch-register)
endif
ifdef CONFIG_CC_IS_CLANG
RETPOLINE_CFLAGS	:= -mretpoline-external-thunk
RETPOLINE_VDSO_CFLAGS	:= -mretpoline
endif
696 697 698
export RETPOLINE_CFLAGS
export RETPOLINE_VDSO_CFLAGS

699
include $(srctree)/arch/$(SRCARCH)/Makefile
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700

701 702
ifdef need-config
ifdef may-sync-config
703 704 705
# 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.
706
include include/config/auto.conf.cmd
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708 709 710 711 712 713 714 715
$(KCONFIG_CONFIG):
	@echo >&2 '***'
	@echo >&2 '*** Configuration file "$@" 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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717 718 719
# 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).
720 721 722
#
# This exploits the 'multi-target pattern rule' trick.
# The syncconfig should be executed only once to make all the targets.
723
# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
724 725 726
#
# Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
# so you cannot notice that Kconfig is waiting for the user input.
727
%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h: $(KCONFIG_CONFIG)
728 729
	$(Q)$(kecho) "  SYNC    $@"
	$(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
730
else # !may-sync-config
731 732 733
# 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
734 735 736
PHONY += include/config/auto.conf

include/config/auto.conf:
737
	$(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 ;							\
743 744
	/bin/false)

745
endif # may-sync-config
746
endif # need-config
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748
KBUILD_CFLAGS	+= -fno-delete-null-pointer-checks
749
KBUILD_CFLAGS	+= $(call cc-disable-warning,frame-address,)
750 751
KBUILD_CFLAGS	+= $(call cc-disable-warning, format-truncation)
KBUILD_CFLAGS	+= $(call cc-disable-warning, format-overflow)
752
KBUILD_CFLAGS	+= $(call cc-disable-warning, address-of-packed-member)
753

754 755 756 757 758 759
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
760
endif
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761

762
# Tell gcc to never replace conditional load with a non-conditional one
763 764 765
ifdef CONFIG_CC_IS_GCC
# gcc-10 renamed --param=allow-store-data-races=0 to
# -fno-allow-store-data-races.
766
KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
767
KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
768
endif
769

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770 771 772 773 774
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
775
KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
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endif

778
ifneq ($(CONFIG_FRAME_WARN),0)
779
KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
780 781
endif

782
stackp-flags-y                                    := -fno-stack-protector
783 784
stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
785 786

KBUILD_CFLAGS += $(stackp-flags-y)
787

788 789 790
KBUILD_CFLAGS-$(CONFIG_WERROR) += -Werror
KBUILD_CFLAGS += $(KBUILD_CFLAGS-y)

791
ifdef CONFIG_CC_IS_CLANG
792
KBUILD_CPPFLAGS += -Qunused-arguments
793
# The kernel builds with '-std=gnu89' so use of GNU extensions is acceptable.
794
KBUILD_CFLAGS += -Wno-gnu
795 796 797
# 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
798
KBUILD_CFLAGS += -mno-global-merge
799 800 801 802 803 804
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,)
805 806
# gcc inanely warns about local variables called 'main'
KBUILD_CFLAGS += -Wno-main
807 808
endif

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)
813

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814
ifdef CONFIG_FRAME_POINTER
815
KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
L
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816
else
817 818 819 820 821 822
# 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
823
KBUILD_CFLAGS	+= -fomit-frame-pointer
L
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824
endif
825
endif
L
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826

827 828
# Initialize all stack variables with a 0xAA pattern.
ifdef CONFIG_INIT_STACK_ALL_PATTERN
829 830 831
KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
endif

832 833 834 835 836 837 838 839 840
# 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

841 842 843 844
# 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)

845 846 847 848 849
# Clear used registers at func exit (to reduce data lifetime and ROP gadgets).
ifdef CONFIG_ZERO_CALL_USED_REGS
KBUILD_CFLAGS	+= -fzero-call-used-regs=used-gpr
endif

850 851
DEBUG_CFLAGS	:=

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
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858
endif
859

860
ifndef CONFIG_AS_IS_LLVM
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
871 872 873 874
DEBUG_CFLAGS	+= -fno-var-tracking
ifdef CONFIG_CC_IS_GCC
DEBUG_CFLAGS	+= -femit-struct-debug-baseonly
endif
875 876
endif

877 878
ifdef CONFIG_DEBUG_INFO_COMPRESSED
DEBUG_CFLAGS	+= -gz=zlib
879
KBUILD_AFLAGS	+= -gz=zlib
880 881 882
KBUILD_LDFLAGS	+= --compress-debug-sections=zlib
endif

883 884
endif # CONFIG_DEBUG_INFO

885 886 887
KBUILD_CFLAGS += $(DEBUG_CFLAGS)
export DEBUG_CFLAGS

888
ifdef CONFIG_FUNCTION_TRACER
889 890
ifdef CONFIG_FTRACE_MCOUNT_USE_CC
  CC_FLAGS_FTRACE	+= -mrecord-mcount
891 892 893 894 895 896
  ifdef CONFIG_HAVE_NOP_MCOUNT
    ifeq ($(call cc-option-yn, -mnop-mcount),y)
      CC_FLAGS_FTRACE	+= -mnop-mcount
      CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
    endif
  endif
897
endif
898 899 900
ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
  CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
endif
901 902 903 904 905 906
ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
  ifdef CONFIG_HAVE_C_RECORDMCOUNT
    BUILD_C_RECORDMCOUNT := y
    export BUILD_C_RECORDMCOUNT
  endif
endif
907
ifdef CONFIG_HAVE_FENTRY
908
  # s390-linux-gnu-gcc did not support -mfentry until gcc-9.
909 910 911 912
  ifeq ($(call cc-option-yn, -mfentry),y)
    CC_FLAGS_FTRACE	+= -mfentry
    CC_FLAGS_USING	+= -DCC_USING_FENTRY
  endif
913
endif
914 915 916
export CC_FLAGS_FTRACE
KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
917 918
endif

919 920
# We trigger additional mismatches with less inlining
ifdef CONFIG_DEBUG_SECTION_MISMATCH
921
KBUILD_CFLAGS += -fno-inline-functions-called-once
922 923
endif

924
ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
925 926
KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
LDFLAGS_vmlinux += --gc-sections
927 928
endif

929 930 931 932 933 934
ifdef CONFIG_SHADOW_CALL_STACK
CC_FLAGS_SCS	:= -fsanitize=shadow-call-stack
KBUILD_CFLAGS	+= $(CC_FLAGS_SCS)
export CC_FLAGS_SCS
endif

935 936
ifdef CONFIG_LTO_CLANG
ifdef CONFIG_LTO_CLANG_THIN
937
CC_FLAGS_LTO	:= -flto=thin -fsplit-lto-unit
938
KBUILD_LDFLAGS	+= --thinlto-cache-dir=$(extmod_prefix).thinlto-cache
939
else
940
CC_FLAGS_LTO	:= -flto
941 942
endif
CC_FLAGS_LTO	+= -fvisibility=hidden
S
Sami Tolvanen 已提交
943 944 945

# Limit inlining across translation units to reduce binary size
KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
946

947 948
# Check for frame size exceeding threshold during prolog/epilog insertion
# when using lld < 13.0.0.
949
ifneq ($(CONFIG_FRAME_WARN),0)
950
ifeq ($(shell test $(CONFIG_LLD_VERSION) -lt 130000; echo $$?),0)
951 952
KBUILD_LDFLAGS	+= -plugin-opt=-warn-stack-size=$(CONFIG_FRAME_WARN)
endif
953
endif
954
endif
955 956

ifdef CONFIG_LTO
957 958
KBUILD_CFLAGS	+= -fno-lto $(CC_FLAGS_LTO)
KBUILD_AFLAGS	+= -fno-lto
959 960 961
export CC_FLAGS_LTO
endif

S
Sami Tolvanen 已提交
962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978
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

979 980
ifdef CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_64B
KBUILD_CFLAGS += -falign-functions=64
981 982
endif

983
# arch Makefile may override CC so keep this after arch Makefile is included
M
Masahiro Yamada 已提交
984
NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
985

L
Linus Torvalds 已提交
986
# warn about C99 declaration after statement
987
KBUILD_CFLAGS += -Wdeclaration-after-statement
L
Linus Torvalds 已提交
988

K
Kees Cook 已提交
989
# Variable Length Arrays (VLAs) should not be used anywhere in the kernel
990
KBUILD_CFLAGS += -Wvla
K
Kees Cook 已提交
991

S
Sam Ravnborg 已提交
992
# disable pointer signed / unsigned warnings in gcc 4.0
993
KBUILD_CFLAGS += -Wno-pointer-sign
L
Linus Torvalds 已提交
994

995 996 997
# disable stringop warnings in gcc 8+
KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)

998 999
# 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)
1000
KBUILD_CFLAGS += -Wno-array-bounds
1001
KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
1002

1003 1004 1005
# Another good warning that we'll want to enable eventually
KBUILD_CFLAGS += $(call cc-disable-warning, restrict)

1006
# Enabled with W=2, disabled by default as noisy
1007 1008 1009
ifdef CONFIG_CC_IS_GCC
KBUILD_CFLAGS += -Wno-maybe-uninitialized
endif
1010

1011
# disable invalid "can't wrap" optimizations for signed / pointers
1012
KBUILD_CFLAGS	+= -fno-strict-overflow
1013

1014
# Make sure -fstack-check isn't enabled (like gentoo apparently did)
1015
KBUILD_CFLAGS  += -fno-stack-check
1016

1017
# conserve stack if available
1018 1019 1020
ifdef CONFIG_CC_IS_GCC
KBUILD_CFLAGS   += -fconserve-stack
endif
1021

1022
# Prohibit date/time macros, which would make the build non-deterministic
1023
KBUILD_CFLAGS   += -Werror=date-time
1024

1025 1026 1027
# enforce correct pointer usage
KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)

1028 1029 1030
# Require designated initializers for all marked structures
KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)

1031
# change __FILE__ to the relative path from the srctree
1032
KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
1033

1034 1035 1036 1037 1038 1039 1040 1041 1042
# 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))
1043

1044 1045 1046
# 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.
1047

1048 1049 1050 1051
# Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
KBUILD_CPPFLAGS += $(KCPPFLAGS)
KBUILD_AFLAGS   += $(KAFLAGS)
KBUILD_CFLAGS   += $(KCFLAGS)
1052

1053 1054
KBUILD_LDFLAGS_MODULE += --build-id=sha1
LDFLAGS_vmlinux += --build-id=sha1
R
Roland McGrath 已提交
1055

1056
ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1057
LDFLAGS_vmlinux	+= $(call ld-option, -X,)
1058 1059
endif

1060
ifeq ($(CONFIG_RELR),y)
1061
LDFLAGS_vmlinux	+= --pack-dyn-relocs=relr --use-android-relr-tags
1062 1063
endif

1064 1065 1066 1067 1068 1069
# 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

1070
# Align the bit size of userspace programs with the kernel
1071 1072
KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1073

1074 1075 1076
# make the checker run with the right architecture
CHECKFLAGS += --arch=$(ARCH)

1077 1078 1079
# insure the checker run with the right endianness
CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)

1080 1081 1082
# the checker needs the correct machine size
CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)

L
Linus Torvalds 已提交
1083
# Default kernel image to build when no specific target is given.
S
Sam Ravnborg 已提交
1084
# KBUILD_IMAGE may be overruled on the command line or
L
Linus Torvalds 已提交
1085 1086 1087 1088 1089 1090 1091 1092 1093 1094
# 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

1095 1096 1097 1098 1099 1100 1101
#
# 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
1102 1103 1104
#
# 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
1105
# makefile but the argument can be passed to make if needed.
L
Linus Torvalds 已提交
1106 1107
#

1108
MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
L
Linus Torvalds 已提交
1109 1110
export MODLIB

1111
PHONY += prepare0
1112

1113
export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
1114 1115
export MODORDER := $(extmod_prefix)modules.order
export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
1116

L
Linus Torvalds 已提交
1117
ifeq ($(KBUILD_EXTMOD),)
1118
core-y		+= kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
L
Linus Torvalds 已提交
1119

1120
vmlinux-dirs	:= $(patsubst %/,%,$(filter %/, \
L
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1121
		     $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
1122
		     $(libs-y) $(libs-m)))
L
Linus Torvalds 已提交
1123

1124
vmlinux-alldirs	:= $(sort $(vmlinux-dirs) Documentation \
1125
		     $(patsubst %/,%,$(filter %/, $(core-) \
1126
			$(drivers-) $(libs-))))
L
Linus Torvalds 已提交
1127

1128 1129 1130
subdir-modorder := $(addsuffix modules.order,$(filter %/, \
			$(core-y) $(core-m) $(libs-y) $(libs-m) \
			$(drivers-y) $(drivers-m)))
L
Linus Torvalds 已提交
1131

1132
build-dirs	:= $(vmlinux-dirs)
1133
clean-dirs	:= $(vmlinux-alldirs)
1134

1135 1136 1137
# 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)))
1138
ifdef CONFIG_MODULES
1139 1140
KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1141
else
1142
KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1143
endif
1144
KBUILD_VMLINUX_OBJS += $(patsubst %/,%/built-in.a, $(drivers-y))
L
Linus Torvalds 已提交
1145

1146
export KBUILD_VMLINUX_OBJS KBUILD_VMLINUX_LIBS
1147
export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1148
# used by scripts/Makefile.package
1149
export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) LICENSES arch include scripts tools)
1150

1151
vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
L
Linus Torvalds 已提交
1152

1153 1154
# Recurse until adjust_autoksyms.sh is satisfied
PHONY += autoksyms_recursive
1155
ifdef CONFIG_TRIM_UNUSED_KSYMS
1156 1157 1158
# 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)
1159 1160 1161 1162 1163
KBUILD_MODULES := 1

autoksyms_recursive: descend modules.order
	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
	  "$(MAKE) -f $(srctree)/Makefile vmlinux"
1164 1165
endif

1166 1167
autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)

1168 1169 1170 1171
quiet_cmd_autoksyms_h = GEN     $@
      cmd_autoksyms_h = mkdir -p $(dir $@); \
			$(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@

1172
$(autoksyms_h):
1173
	$(call cmd,autoksyms_h)
1174

1175 1176 1177
ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)

# Final link of vmlinux with optional arch pass after final link
1178
cmd_link-vmlinux =                                                 \
1179
	$(CONFIG_SHELL) $< "$(LD)" "$(KBUILD_LDFLAGS)" "$(LDFLAGS_vmlinux)";    \
1180
	$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1181

1182
vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1183
	+$(call if_changed_dep,link-vmlinux)
1184

1185 1186
targets := vmlinux

1187
# The actual objects are generated when descending,
L
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1188
# make sure no implicit rule kicks in
1189
$(sort $(vmlinux-deps) $(subdir-modorder)): descend ;
L
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1190

1191
filechk_kernel.release = \
1192 1193
	echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"

G
Geert Uytterhoeven 已提交
1194
# Store (new) KERNELRELEASE string in include/config/kernel.release
1195
include/config/kernel.release: FORCE
1196
	$(call filechk,kernel.release)
1197

1198 1199 1200 1201
# Additional helpers built in scripts/
# Carefully list dependencies so we do not try to build scripts twice
# in parallel
PHONY += scripts
1202
scripts: scripts_basic scripts_dtc
1203
	$(Q)$(MAKE) $(build)=$(@)
1204

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1205
# Things we need to do before we recursively start building the kernel
1206 1207 1208 1209
# 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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1210

M
Masahiro Yamada 已提交
1211
PHONY += prepare archprepare
1212

1213
archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1214
	asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h \
1215
	include/generated/autoconf.h remove-stale-files
1216

1217
prepare0: archprepare
1218
	$(Q)$(MAKE) $(build)=scripts/mod
1219
	$(Q)$(MAKE) $(build)=.
1220

L
Linus Torvalds 已提交
1221
# All the preparing..
1222
prepare: prepare0
1223

1224 1225 1226 1227
PHONY += remove-stale-files
remove-stale-files:
	$(Q)$(srctree)/scripts/remove-stale-files

1228
# Support for using generic headers in asm-generic
1229 1230
asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj

1231 1232
PHONY += asm-generic uapi-asm-generic
asm-generic: uapi-asm-generic
1233 1234
	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
	generic=include/asm-generic
1235
uapi-asm-generic:
1236 1237
	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
	generic=include/uapi/asm-generic
1238

L
Linus Torvalds 已提交
1239 1240 1241 1242 1243 1244 1245
# 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
Sam Ravnborg 已提交
1246 1247 1248 1249 1250
define filechk_utsrelease.h
	if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
	  exit 1;                                                         \
	fi;                                                               \
1251
	echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
S
Sam Ravnborg 已提交
1252
endef
L
Linus Torvalds 已提交
1253 1254

define filechk_version.h
S
Sasha Levin 已提交
1255 1256
	if [ $(SUBLEVEL) -gt 255 ]; then                                 \
		echo \#define LINUX_VERSION_CODE $(shell                 \
1257
		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
S
Sasha Levin 已提交
1258 1259
	else                                                             \
		echo \#define LINUX_VERSION_CODE $(shell                 \
1260
		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
S
Sasha Levin 已提交
1261 1262
	fi;                                                              \
	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
1263 1264 1265 1266
	((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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1267 1268
endef

1269 1270
$(version_h): PATCHLEVEL := $(if $(PATCHLEVEL), $(PATCHLEVEL), 0)
$(version_h): SUBLEVEL := $(if $(SUBLEVEL), $(SUBLEVEL), 0)
1271
$(version_h): FORCE
L
Linus Torvalds 已提交
1272 1273
	$(call filechk,version.h)

1274
include/generated/utsrelease.h: include/config/kernel.release FORCE
S
Sam Ravnborg 已提交
1275 1276
	$(call filechk,utsrelease.h)

1277 1278
PHONY += headerdep
headerdep:
1279 1280
	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
	$(srctree)/scripts/headerdep.pl -I$(srctree)/include
1281

1282 1283 1284
# ---------------------------------------------------------------------------
# Kernel headers

1285 1286
#Default location for installed headers
export INSTALL_HDR_PATH = $(objtree)/usr
1287

1288 1289 1290 1291 1292
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)
1293

1294
PHONY += headers_install
1295 1296
headers_install: headers
	$(call cmd,headers_install)
1297

1298
PHONY += archheaders archscripts
1299

1300
hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1301

1302 1303
PHONY += headers
headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1304
	$(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1305
	  $(error Headers not exportable for the $(SRCARCH) architecture))
1306 1307
	$(Q)$(MAKE) $(hdr-inst)=include/uapi
	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1308

1309
# Deprecated. It is no-op now.
1310
PHONY += headers_check
1311
headers_check:
1312 1313 1314 1315 1316
	@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 "==============================================="
1317

1318
ifdef CONFIG_HEADERS_INSTALL
1319
prepare: headers
1320
endif
1321

1322 1323 1324 1325
PHONY += scripts_unifdef
scripts_unifdef: scripts_basic
	$(Q)$(MAKE) $(build)=scripts scripts/unifdef

1326 1327 1328 1329 1330 1331 1332 1333 1334 1335
# ---------------------------------------------------------------------------
# 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 :=

1336 1337 1338
# ---------------------------------------------------------------------------
# Tools

1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359
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

1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372
# 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/ $*

1373 1374 1375 1376 1377
# ---------------------------------------------------------------------------
# Kernel selftest

PHONY += kselftest
kselftest:
1378
	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1379

1380 1381
kselftest-%: FORCE
	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
W
Wang Long 已提交
1382

1383 1384 1385
PHONY += kselftest-merge
kselftest-merge:
	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1386 1387
	$(Q)find $(srctree)/tools/testing/selftests -name config | \
		xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1388
	$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1389

1390 1391 1392 1393 1394 1395 1396 1397 1398
# ---------------------------------------------------------------------------
# Devicetree files

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

ifneq ($(dtstree),)

M
Masahiro Yamada 已提交
1399
%.dtb: include/config/kernel.release scripts_dtc
1400 1401
	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@

1402 1403 1404
%.dtbo: include/config/kernel.release scripts_dtc
	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@

1405
PHONY += dtbs dtbs_install dtbs_check
1406
dtbs: include/config/kernel.release scripts_dtc
1407 1408
	$(Q)$(MAKE) $(build)=$(dtstree)

1409
ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1410
export CHECK_DTBS=y
1411 1412 1413 1414
dtbs: dt_binding_check
endif

dtbs_check: dtbs
1415

1416
dtbs_install:
1417
	$(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428

ifdef CONFIG_OF_EARLY_FLATTREE
all: dtbs
endif

endif

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

1429 1430 1431 1432
ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
export CHECK_DT_BINDING=y
endif

1433
PHONY += dt_binding_check
1434 1435 1436
dt_binding_check: scripts_dtc
	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings

L
Linus Torvalds 已提交
1437 1438 1439 1440 1441
# ---------------------------------------------------------------------------
# Modules

ifdef CONFIG_MODULES

S
Sam Ravnborg 已提交
1442
# By default, build modules as well
L
Linus Torvalds 已提交
1443

1444
all: modules
L
Linus Torvalds 已提交
1445

1446 1447 1448 1449 1450 1451 1452
# 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

1453
# Build modules
T
Tejun Heo 已提交
1454
#
1455 1456 1457
# 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
1458

1459
PHONY += modules
1460
modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_check modules_prepare
L
Linus Torvalds 已提交
1461

1462 1463 1464 1465 1466 1467
cmd_modules_order = $(AWK) '!x[$$0]++' $(real-prereqs) > $@

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

targets += modules.order
1468

L
Linus Torvalds 已提交
1469
# Target to prepare building external modules
1470
PHONY += modules_prepare
1471
modules_prepare: prepare
1472
	$(Q)$(MAKE) $(build)=scripts scripts/module.lds
L
Linus Torvalds 已提交
1473

1474 1475 1476 1477 1478 1479
export modules_sign_only :=

ifeq ($(CONFIG_MODULE_SIG),y)
PHONY += modules_sign
modules_sign: modules_install
	@:
L
Linus Torvalds 已提交
1480

1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493
# 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)
1494 1495
PHONY += __modinst_pre
__modinst_pre:
L
Linus Torvalds 已提交
1496 1497 1498
	@rm -rf $(MODLIB)/kernel
	@rm -f $(MODLIB)/source
	@mkdir -p $(MODLIB)/kernel
1499
	@ln -s $(abspath $(srctree)) $(MODLIB)/source
L
Linus Torvalds 已提交
1500 1501
	@if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
		rm -f $(MODLIB)/build ; \
1502
		ln -s $(CURDIR) $(MODLIB)/build ; \
L
Linus Torvalds 已提交
1503
	fi
1504
	@sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order
1505 1506
	@cp -f modules.builtin $(MODLIB)/
	@cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
L
Linus Torvalds 已提交
1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517

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'
1518
CLEAN_FILES += include/ksym vmlinux.symvers modules-only.symvers \
1519
	       modules.builtin modules.builtin.modinfo modules.nsdeps \
1520
	       compile_commands.json .thinlto-cache
L
Linus Torvalds 已提交
1521 1522

# Directories & files removed with 'make mrproper'
1523
MRPROPER_FILES += include/config include/generated          \
1524
		  arch/$(SRCARCH)/include/generated .tmp_objdiff \
1525 1526
		  debian snap tar-install \
		  .config .config.old .version \
1527
		  Module.symvers \
1528 1529 1530
		  certs/signing_key.pem certs/signing_key.x509 \
		  certs/x509.genkey \
		  vmlinux-gdb.py \
1531
		  *.spec
L
Linus Torvalds 已提交
1532 1533 1534 1535 1536

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

1537
PHONY += archclean vmlinuxclean
L
Linus Torvalds 已提交
1538

1539 1540
vmlinuxclean:
	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1541
	$(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1542

1543
clean: archclean vmlinuxclean resolve_btfids_clean
L
Linus Torvalds 已提交
1544 1545 1546 1547

# mrproper - Delete all generated files, including .config
#
mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1548
mrproper-dirs      := $(addprefix _mrproper_,scripts)
L
Linus Torvalds 已提交
1549

1550
PHONY += $(mrproper-dirs) mrproper
L
Linus Torvalds 已提交
1551 1552 1553
$(mrproper-dirs):
	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)

1554
mrproper: clean $(mrproper-dirs)
L
Linus Torvalds 已提交
1555 1556 1557 1558
	$(call cmd,rmfiles)

# distclean
#
1559
PHONY += distclean
L
Linus Torvalds 已提交
1560 1561

distclean: mrproper
1562
	@find . $(RCS_FIND_IGNORE) \
S
Sam Ravnborg 已提交
1563
		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1564
		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
1565 1566
		-o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
		-o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
L
Linus Torvalds 已提交
1567 1568 1569 1570 1571 1572
		-type f -print | xargs rm -f


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

1573
%src-pkg: FORCE
1574
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1575
%pkg: include/config/kernel.release FORCE
1576
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
L
Linus Torvalds 已提交
1577 1578 1579 1580

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

1581
boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1582
boards := $(sort $(notdir $(boards)))
1583 1584
board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
board-dirs := $(sort $(notdir $(board-dirs:/=)))
L
Linus Torvalds 已提交
1585

1586
PHONY += help
L
Linus Torvalds 已提交
1587 1588
help:
	@echo  'Cleaning targets:'
1589
	@echo  '  clean		  - Remove most generated files but keep the config and'
1590
	@echo  '                    enough build support to build external modules'
1591
	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
1592
	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
L
Linus Torvalds 已提交
1593 1594 1595 1596 1597 1598 1599 1600
	@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'
1601
	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
L
Linus Torvalds 已提交
1602
	@echo  '  dir/            - Build all files in dir and below'
1603
	@echo  '  dir/file.[ois]  - Build specified target only'
1604 1605
	@echo  '  dir/file.ll     - Build the LLVM assembly file'
	@echo  '                    (requires compiler support for LLVM assembly generation)'
1606 1607
	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
	@echo  '                    (requires a recent binutils and recent build (System.map))'
1608
	@echo  '  dir/file.ko     - Build module including final link'
1609
	@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'
1612
	@echo  '  gtags           - Generate GNU GLOBAL index'
1613 1614 1615
	@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)'
1616
	@echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1617
	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1618
	 echo  ''
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	@echo  'Static analysers:'
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1620
	@echo  '  checkstack      - Generate a list of stack hogs'
1621
	@echo  '  versioncheck    - Sanity check on version.h usage'
1622
	@echo  '  includecheck    - Check for duplicate included header files'
1623
	@echo  '  export_report   - List the usages of all exported symbols'
1624
	@echo  '  headerdep       - Detect inclusion cycles in headers'
1625
	@echo  '  coccicheck      - Check with Coccinelle'
1626 1627
	@echo  '  clang-analyzer  - Check with clang static analyzer'
	@echo  '  clang-tidy      - Check with clang-tidy'
1628
	@echo  ''
1629 1630 1631
	@echo  'Tools:'
	@echo  '  nsdeps          - Generate missing symbol namespace dependencies'
	@echo  ''
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	@echo  'Kernel selftest:'
1633 1634 1635 1636 1637 1638 1639 1640 1641
	@echo  '  kselftest         - Build and run kernel selftest'
	@echo  '                      Build, install, and boot kernel before'
	@echo  '                      running kselftest on it'
	@echo  '                      Run as root for full coverage'
	@echo  '  kselftest-all     - Build kernel selftest'
	@echo  '  kselftest-install - Build and install kernel selftest'
	@echo  '  kselftest-clean   - Remove all generated kselftest files'
	@echo  '  kselftest-merge   - Merge all the config dependencies of'
	@echo  '		      kselftest to existing .config.'
1642
	@echo  ''
1643 1644
	@$(if $(dtstree), \
		echo 'Devicetree:'; \
1645 1646 1647 1648
		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';\
1649 1650
		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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1655
	@echo  'Kernel packaging:'
1656
	@$(MAKE) -f $(srctree)/scripts/Makefile.package help
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1657 1658
	@echo  ''
	@echo  'Documentation targets:'
1659
	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
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1660
	@echo  ''
1661
	@echo  'Architecture specific targets ($(SRCARCH)):'
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1662
	@$(if $(archhelp),$(archhelp),\
1663
		echo '  No architecture specific help defined for $(SRCARCH)')
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1664 1665 1666
	@echo  ''
	@$(if $(boards), \
		$(foreach b, $(boards), \
1667
		printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
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		echo '')
1669 1670 1671 1672 1673
	@$(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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1674 1675

	@echo  '  make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1676
	@echo  '  make V=2   [targets] 2 => give reason for rebuild of target'
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	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1678 1679
	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
	@echo  '                       (sparse by default)'
1680
	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1681
	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1682
	@echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
1683 1684 1685
	@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'
1686
	@echo  '		Multiple levels can be combined with W=12 or W=123'
L
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1687 1688 1689 1690 1691
	@echo  ''
	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
	@echo  'For further info see the ./README file'


1692 1693 1694 1695
help-board-dirs := $(addprefix help-,$(board-dirs))

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

1696
boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1697 1698 1699 1700 1701 1702 1703 1704 1705

$(help-board-dirs): help-%:
	@echo  'Architecture specific targets ($(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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1706 1707
# Documentation targets
# ---------------------------------------------------------------------------
1708 1709
DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
	       linkcheckdocs dochelp refcheckdocs
1710
PHONY += $(DOC_TARGETS)
1711
$(DOC_TARGETS):
1712
	$(Q)$(MAKE) $(build)=Documentation $@
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1713

1714 1715 1716 1717
# Misc
# ---------------------------------------------------------------------------

PHONY += scripts_gdb
1718
scripts_gdb: prepare0
1719
	$(Q)$(MAKE) $(build)=scripts/gdb
1720
	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1721 1722 1723 1724 1725

ifdef CONFIG_GDB_SCRIPTS
all: scripts_gdb
endif

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1726 1727 1728 1729 1730 1731 1732
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
1733
# in the basis kernel ordinary make commands (without M=...) must be used.
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1734

1735 1736
# We are always building only modules.
KBUILD_BUILTIN :=
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1737 1738
KBUILD_MODULES := 1

1739
build-dirs := $(KBUILD_EXTMOD)
1740 1741 1742
$(MODORDER): descend
	@:

1743
compile_commands.json: $(extmod_prefix)compile_commands.json
1744 1745
PHONY += compile_commands.json

1746
clean-dirs := $(KBUILD_EXTMOD)
1747
clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1748
	$(KBUILD_EXTMOD)/compile_commands.json $(KBUILD_EXTMOD)/.thinlto-cache
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1749

1750 1751 1752 1753 1754 1755 1756 1757 1758 1759
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

1760
PHONY += help
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1761 1762 1763 1764 1765 1766 1767 1768
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  ''
1769

1770
# no-op for external module builds
1771
PHONY += modules_prepare
1772

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endif # KBUILD_EXTMOD

1775 1776 1777 1778 1779 1780 1781
# ---------------------------------------------------------------------------
# Modules

PHONY += modules modules_install

ifdef CONFIG_MODULES

1782
modules: modules_check
1783 1784
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost

1785 1786 1787 1788
PHONY += modules_check
modules_check: $(MODORDER)
	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<

1789
quiet_cmd_depmod = DEPMOD  $(MODLIB)
1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811
      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

1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841
# 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
1842
single_modpost: $(single-no-ko) modules_prepare
1843
	$(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$m;) } > $(MODORDER)
1844 1845 1846 1847
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost

KBUILD_MODULES := 1

1848
export KBUILD_SINGLE_TARGETS := $(addprefix $(extmod_prefix), $(single-no-ko))
1849 1850 1851 1852 1853 1854 1855

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

endif

1856 1857 1858 1859
ifndef CONFIG_MODULES
KBUILD_MODULES :=
endif

1860 1861 1862 1863 1864 1865 1866 1867
# 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
1868
	$(Q)$(MAKE) $(build)=$@ \
1869
	single-build=$(if $(filter-out $@/, $(filter $@/%, $(KBUILD_SINGLE_TARGETS))),1) \
1870
	need-builtin=1 need-modorder=1
1871

1872 1873 1874 1875 1876
clean-dirs := $(addprefix _clean_, $(clean-dirs))
PHONY += $(clean-dirs) clean
$(clean-dirs):
	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)

1877 1878
clean: $(clean-dirs)
	$(call cmd,rmfiles)
1879
	@find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1880
		\( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1881
		-o -name '*.ko.*' \
1882
		-o -name '*.dtb' -o -name '*.dtbo' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1883
		-o -name '*.dwo' -o -name '*.lst' \
1884
		-o -name '*.su' -o -name '*.mod' \
1885
		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1886
		-o -name '*.lex.c' -o -name '*.tab.[ch]' \
1887
		-o -name '*.asn1.[ch]' \
1888
		-o -name '*.symtypes' -o -name 'modules.order' \
1889
		-o -name '.tmp_*.o.*' \
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		-o -name '*.c.[012]*.*' \
1891
		-o -name '*.ll' \
1892 1893
		-o -name '*.gcno' \
		-o -name '*.*.symversions' \) -type f -print | xargs rm -f
1894

L
Linus Torvalds 已提交
1895 1896
# Generate tags for editors
# ---------------------------------------------------------------------------
1897
quiet_cmd_tags = GEN     $@
1898
      cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
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1899

1900
tags TAGS cscope gtags: FORCE
L
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1901 1902
	$(call cmd,tags)

1903 1904 1905 1906
# Script to generate missing namespace dependencies
# ---------------------------------------------------------------------------

PHONY += nsdeps
1907
nsdeps: export KBUILD_NSDEPS=1
1908
nsdeps: modules
1909
	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1910

1911 1912 1913 1914 1915 1916
# Clang Tooling
# ---------------------------------------------------------------------------

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

1917
$(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
1918 1919 1920 1921
	$(if $(KBUILD_EXTMOD),,$(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)) \
	$(if $(CONFIG_MODULES), $(MODORDER)) FORCE
	$(call if_changed,gen_compile_commands)

1922
targets += $(extmod_prefix)compile_commands.json
1923

1924 1925 1926 1927 1928 1929
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 $@ $<

1930
clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
1931 1932 1933 1934 1935 1936 1937
	$(call cmd,clang_tools)
else
clang-tidy clang-analyzer:
	@echo "$@ requires CC=clang" >&2
	@false
endif

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1938 1939 1940
# Scripts to check various things for consistency
# ---------------------------------------------------------------------------

J
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1941
PHONY += includecheck versioncheck coccicheck export_report
P
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1942

L
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1943
includecheck:
1944
	find $(srctree)/* $(RCS_FIND_IGNORE) \
L
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1945
		-name '*.[hcS]' -type f -print | sort \
1946
		| xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
L
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1947 1948

versioncheck:
1949
	find $(srctree)/* $(RCS_FIND_IGNORE) \
L
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1950
		-name '*.[hcS]' -type f -print | sort \
1951
		| xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
L
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1952

1953
coccicheck:
1954
	$(Q)$(BASH) $(srctree)/scripts/$@
1955

1956 1957 1958
export_report:
	$(PERL) $(srctree)/scripts/export_report.pl

1959
PHONY += checkstack kernelrelease kernelversion image_name
J
Jeff Dike 已提交
1960

J
Jeff Dike 已提交
1961 1962 1963 1964 1965 1966 1967 1968 1969
# 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
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1970 1971
checkstack:
	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1972
	$(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
L
Linus Torvalds 已提交
1973

1974 1975
kernelrelease:
	@echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1976

1977
kernelversion:
1978
	@echo $(KERNELVERSION)
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1979

1980 1981 1982
image_name:
	@echo $(KBUILD_IMAGE)

L
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1983
quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
1984
      cmd_rmfiles = rm -rf $(rm-files)
L
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1985

1986 1987
# read saved command lines for existing targets
existing-targets := $(wildcard $(sort $(targets)))
L
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1988

1989
-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
L
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1990

1991
endif # config-build
1992 1993
endif # mixed-build
endif # need-sub-make
L
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1994

1995
PHONY += FORCE
L
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1996
FORCE:
1997

1998
# Declare the contents of the PHONY variable as phony.  We keep that
1999
# information in a variable so we can use it in if_changed and friends.
2000
.PHONY: $(PHONY)