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# SPDX-License-Identifier: GPL-2.0
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VERSION = 5
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PATCHLEVEL = 11
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SUBLEVEL = 0
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EXTRAVERSION = -rc7
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NAME = Kleptomaniac Octopus
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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_
endif

export quiet Q KBUILD_VERBOSE

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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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abs_srctree := $(realpath $(dir $(lastword $(MAKEFILE_LIST))))
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ifneq ($(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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this-makefile := $(lastword $(MAKEFILE_LIST))

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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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# 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.
#
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# See the file "Documentation/dev-tools/sparse.rst" for more details,
# including where to get the "sparse" utility.
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ifeq ("$(origin C)", "command line")
  KBUILD_CHECKSRC = $(C)
endif
ifndef KBUILD_CHECKSRC
  KBUILD_CHECKSRC = 0
endif

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

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

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export KBUILD_CHECKSRC KBUILD_EXTMOD

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extmod-prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)

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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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no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease
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single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
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config-build	:=
mixed-build	:=
need-config	:= 1
may-sync-config	:= 1
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single-build	:=
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ifneq ($(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-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 scripts/Kbuild.include

# Read KERNELRELEASE from include/config/kernel.release (if it exists)
KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION

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include 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 ($(ARCH),sparc64)
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       SRCARCH := sparc
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endif
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# Additional ARCH settings for sh
ifeq ($(ARCH),sh64)
       SRCARCH := sh
endif

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KCONFIG_CONFIG	?= .config
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export KCONFIG_CONFIG
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# Default file for 'make defconfig'. This may be overridden by arch-Makefile.
export KBUILD_DEFCONFIG := defconfig

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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/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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	$(Q)rm -f .tmp_quiet_recordmcount
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PHONY += outputmakefile
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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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outputmakefile:
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ifdef building_out_of_srctree
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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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	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile $(srctree)
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	$(Q)test -e .gitignore || \
	{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
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endif
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# The expansion should be delayed until arch/$(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.
CC_VERSION_TEXT = $(shell $(CC) --version 2>/dev/null | head -n 1)

ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
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ifneq ($(CROSS_COMPILE),)
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CLANG_FLAGS	+= --target=$(notdir $(CROSS_COMPILE:%-=%))
569
GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
570
CLANG_FLAGS	+= --prefix=$(GCC_TOOLCHAIN_DIR)$(notdir $(CROSS_COMPILE))
571
GCC_TOOLCHAIN	:= $(realpath $(GCC_TOOLCHAIN_DIR)/..)
572 573
endif
ifneq ($(GCC_TOOLCHAIN),)
574
CLANG_FLAGS	+= --gcc-toolchain=$(GCC_TOOLCHAIN)
575
endif
576
ifneq ($(LLVM_IAS),1)
577
CLANG_FLAGS	+= -no-integrated-as
578
endif
579
CLANG_FLAGS	+= -Werror=unknown-warning-option
580 581
KBUILD_CFLAGS	+= $(CLANG_FLAGS)
KBUILD_AFLAGS	+= $(CLANG_FLAGS)
582
export CLANG_FLAGS
583 584
endif

585
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'
593
include arch/$(SRCARCH)/Makefile
594
export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
L
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595

596
config: outputmakefile scripts_basic FORCE
S
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597 598
	$(Q)$(MAKE) $(build)=scripts/kconfig $@

599
%config: outputmakefile scripts_basic FORCE
L
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600 601
	$(Q)$(MAKE) $(build)=scripts/kconfig $@

602
else #!config-build
L
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603 604 605 606
# ===========================================================================
# Build targets only - this includes vmlinux, arch specific targets, clean
# targets and others. In general all targets except *config targets.

607
# If building an external module we do not care about the all: rule
608
# but instead __all depend on modules
609 610
PHONY += all
ifeq ($(KBUILD_EXTMOD),)
611
__all: all
612
else
613
__all: modules
614 615 616 617 618 619 620 621 622 623
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)
624
  KBUILD_BUILTIN :=
625 626 627 628 629 630
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

631
ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
632 633 634 635 636 637 638 639 640
  KBUILD_MODULES := 1
endif

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

export KBUILD_MODULES KBUILD_BUILTIN

641
ifdef need-config
642 643 644
include include/config/auto.conf
endif

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645 646
ifeq ($(KBUILD_EXTMOD),)
# Objects we will link into vmlinux / subdirs we need to visit
647
core-y		:= init/ usr/
648
drivers-y	:= drivers/ sound/
649
drivers-$(CONFIG_SAMPLES) += samples/
650
drivers-y	+= net/ virt/
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651 652 653
libs-y		:= lib/
endif # KBUILD_EXTMOD

654 655 656 657 658 659 660 661 662
# 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,)
663
export CFLAGS_GCOV
664

665 666 667 668 669
# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
ifdef CONFIG_FUNCTION_TRACER
  CC_FLAGS_FTRACE := -pg
endif

670 671 672 673 674 675 676 677 678
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

679
include arch/$(SRCARCH)/Makefile
L
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680

681 682
ifdef need-config
ifdef may-sync-config
683 684 685
# 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.
686
include include/config/auto.conf.cmd
L
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688 689 690 691 692 693 694 695
$(KCONFIG_CONFIG):
	@echo >&2 '***'
	@echo >&2 '*** Configuration file "$@" 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
L
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696

697 698 699
# 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).
700 701 702
#
# This exploits the 'multi-target pattern rule' trick.
# The syncconfig should be executed only once to make all the targets.
703
# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
704 705 706
quiet_cmd_syncconfig = SYNC    $@
      cmd_syncconfig = $(MAKE) -f $(srctree)/Makefile syncconfig

707
%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h: $(KCONFIG_CONFIG)
708
	+$(call cmd,syncconfig)
709
else # !may-sync-config
710 711 712
# 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
713 714 715
PHONY += include/config/auto.conf

include/config/auto.conf:
716
	$(Q)test -e include/generated/autoconf.h -a -e $@ || (		\
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Michal Marek 已提交
717 718 719 720 721
	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 ;							\
722 723
	/bin/false)

724
endif # may-sync-config
725
endif # need-config
L
Linus Torvalds 已提交
726

727
KBUILD_CFLAGS	+= $(call cc-option,-fno-delete-null-pointer-checks,)
728
KBUILD_CFLAGS	+= $(call cc-disable-warning,frame-address,)
729 730
KBUILD_CFLAGS	+= $(call cc-disable-warning, format-truncation)
KBUILD_CFLAGS	+= $(call cc-disable-warning, format-overflow)
731
KBUILD_CFLAGS	+= $(call cc-disable-warning, address-of-packed-member)
732

733 734 735 736 737 738
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
739
endif
L
Linus Torvalds 已提交
740

741 742
# Tell gcc to never replace conditional load with a non-conditional one
KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
743
KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
744

A
Andi Kleen 已提交
745 746 747 748 749 750 751 752 753 754
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

755
ifneq ($(CONFIG_FRAME_WARN),0)
756
KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
757 758
endif

759
stackp-flags-y                                    := -fno-stack-protector
760 761
stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
762 763

KBUILD_CFLAGS += $(stackp-flags-y)
764

765
ifdef CONFIG_CC_IS_CLANG
766 767 768
KBUILD_CPPFLAGS += -Qunused-arguments
KBUILD_CFLAGS += -Wno-format-invalid-specifier
KBUILD_CFLAGS += -Wno-gnu
769 770 771
# 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
772
KBUILD_CFLAGS += -mno-global-merge
773 774 775 776
else

# These warnings generated too much noise in a regular build.
# Use make W=1 to enable them (see scripts/Makefile.extrawarn)
777
KBUILD_CFLAGS += -Wno-unused-but-set-variable
778 779 780 781 782

# 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,)
783 784
endif

785
KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
L
Linus Torvalds 已提交
786
ifdef CONFIG_FRAME_POINTER
787
KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
L
Linus Torvalds 已提交
788
else
789 790 791 792 793 794
# 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
795
KBUILD_CFLAGS	+= -fomit-frame-pointer
L
Linus Torvalds 已提交
796
endif
797
endif
L
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798

799 800
# Initialize all stack variables with a 0xAA pattern.
ifdef CONFIG_INIT_STACK_ALL_PATTERN
801 802 803
KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
endif

804 805 806 807 808 809 810 811 812
# 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

813 814
DEBUG_CFLAGS	:=

815 816 817
# Workaround for GCC versions < 5.0
# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61801
ifdef CONFIG_CC_IS_GCC
818
DEBUG_CFLAGS	+= $(call cc-ifversion, -lt, 0500, $(call cc-option, -fno-var-tracking-assignments))
819
endif
820

L
Linus Torvalds 已提交
821
ifdef CONFIG_DEBUG_INFO
822

A
Andi Kleen 已提交
823
ifdef CONFIG_DEBUG_INFO_SPLIT
824
DEBUG_CFLAGS	+= -gsplit-dwarf
A
Andi Kleen 已提交
825
else
826
DEBUG_CFLAGS	+= -g
A
Andi Kleen 已提交
827
endif
828

829
ifneq ($(LLVM_IAS),1)
830
KBUILD_AFLAGS	+= -Wa,-gdwarf-2
831
endif
832

833 834
ifndef CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT
dwarf-version-$(CONFIG_DEBUG_INFO_DWARF4) := 4
835
dwarf-version-$(CONFIG_DEBUG_INFO_DWARF5) := 5
836
DEBUG_CFLAGS	+= -gdwarf-$(dwarf-version-y)
837
endif
L
Linus Torvalds 已提交
838

839
ifdef CONFIG_DEBUG_INFO_REDUCED
840
DEBUG_CFLAGS	+= $(call cc-option, -femit-struct-debug-baseonly) \
841
		   $(call cc-option,-fno-var-tracking)
842 843
endif

844 845
ifdef CONFIG_DEBUG_INFO_COMPRESSED
DEBUG_CFLAGS	+= -gz=zlib
846
KBUILD_AFLAGS	+= -gz=zlib
847 848 849
KBUILD_LDFLAGS	+= --compress-debug-sections=zlib
endif

850 851
endif # CONFIG_DEBUG_INFO

852 853 854
KBUILD_CFLAGS += $(DEBUG_CFLAGS)
export DEBUG_CFLAGS

855
ifdef CONFIG_FUNCTION_TRACER
856 857 858 859 860 861
ifdef CONFIG_FTRACE_MCOUNT_RECORD
  # gcc 5 supports generating the mcount tables directly
  ifeq ($(call cc-option-yn,-mrecord-mcount),y)
    CC_FLAGS_FTRACE	+= -mrecord-mcount
    export CC_USING_RECORD_MCOUNT := 1
  endif
862 863 864 865 866 867
  ifdef CONFIG_HAVE_NOP_MCOUNT
    ifeq ($(call cc-option-yn, -mnop-mcount),y)
      CC_FLAGS_FTRACE	+= -mnop-mcount
      CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
    endif
  endif
868
endif
869
ifdef CONFIG_HAVE_FENTRY
870 871 872 873
  ifeq ($(call cc-option-yn, -mfentry),y)
    CC_FLAGS_FTRACE	+= -mfentry
    CC_FLAGS_USING	+= -DCC_USING_FENTRY
  endif
874
endif
875 876 877
export CC_FLAGS_FTRACE
KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
878
ifdef CONFIG_DYNAMIC_FTRACE
879
	ifdef CONFIG_HAVE_C_RECORDMCOUNT
880 881 882 883
		BUILD_C_RECORDMCOUNT := y
		export BUILD_C_RECORDMCOUNT
	endif
endif
884 885
endif

886 887 888 889 890
# We trigger additional mismatches with less inlining
ifdef CONFIG_DEBUG_SECTION_MISMATCH
KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
endif

891
ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
892 893
KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
LDFLAGS_vmlinux += --gc-sections
894 895
endif

896 897 898 899 900 901
ifdef CONFIG_SHADOW_CALL_STACK
CC_FLAGS_SCS	:= -fsanitize=shadow-call-stack
KBUILD_CFLAGS	+= $(CC_FLAGS_SCS)
export CC_FLAGS_SCS
endif

902 903 904 905
ifdef CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_32B
KBUILD_CFLAGS += -falign-functions=32
endif

906
# arch Makefile may override CC so keep this after arch Makefile is included
M
Masahiro Yamada 已提交
907
NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
908

L
Linus Torvalds 已提交
909
# warn about C99 declaration after statement
910
KBUILD_CFLAGS += -Wdeclaration-after-statement
L
Linus Torvalds 已提交
911

K
Kees Cook 已提交
912
# Variable Length Arrays (VLAs) should not be used anywhere in the kernel
913
KBUILD_CFLAGS += -Wvla
K
Kees Cook 已提交
914

S
Sam Ravnborg 已提交
915
# disable pointer signed / unsigned warnings in gcc 4.0
916
KBUILD_CFLAGS += -Wno-pointer-sign
L
Linus Torvalds 已提交
917

918 919 920
# disable stringop warnings in gcc 8+
KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)

921 922
# 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)
923
KBUILD_CFLAGS += $(call cc-disable-warning, array-bounds)
924
KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
925

926 927 928
# Another good warning that we'll want to enable eventually
KBUILD_CFLAGS += $(call cc-disable-warning, restrict)

929 930 931
# Enabled with W=2, disabled by default as noisy
KBUILD_CFLAGS += $(call cc-disable-warning, maybe-uninitialized)

932
# disable invalid "can't wrap" optimizations for signed / pointers
933
KBUILD_CFLAGS	+= -fno-strict-overflow
934

935
# Make sure -fstack-check isn't enabled (like gentoo apparently did)
936
KBUILD_CFLAGS  += -fno-stack-check
937

938 939 940
# conserve stack if available
KBUILD_CFLAGS   += $(call cc-option,-fconserve-stack)

941
# Prohibit date/time macros, which would make the build non-deterministic
942
KBUILD_CFLAGS   += -Werror=date-time
943

944 945 946
# enforce correct pointer usage
KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)

947 948 949
# Require designated initializers for all marked structures
KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)

950
# change __FILE__ to the relative path from the srctree
951
KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
952

953 954 955 956 957 958 959 960 961
# 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))
962

963 964 965
# 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.
966

967 968 969 970
# Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
KBUILD_CPPFLAGS += $(KCPPFLAGS)
KBUILD_AFLAGS   += $(KAFLAGS)
KBUILD_CFLAGS   += $(KCFLAGS)
971

972 973
KBUILD_LDFLAGS_MODULE += --build-id=sha1
LDFLAGS_vmlinux += --build-id=sha1
R
Roland McGrath 已提交
974

975
ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
976
LDFLAGS_vmlinux	+= $(call ld-option, -X,)
977 978
endif

979 980 981 982
ifeq ($(CONFIG_RELR),y)
LDFLAGS_vmlinux	+= --pack-dyn-relocs=relr
endif

983 984 985 986 987 988
# 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

989
# Align the bit size of userspace programs with the kernel
990 991
KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
992

993 994 995
# make the checker run with the right architecture
CHECKFLAGS += --arch=$(ARCH)

996 997 998
# insure the checker run with the right endianness
CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)

999 1000 1001
# the checker needs the correct machine size
CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)

L
Linus Torvalds 已提交
1002
# Default kernel image to build when no specific target is given.
S
Sam Ravnborg 已提交
1003
# KBUILD_IMAGE may be overruled on the command line or
L
Linus Torvalds 已提交
1004 1005 1006 1007 1008 1009 1010 1011 1012 1013
# 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

1014 1015 1016 1017 1018 1019 1020
#
# 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
1021 1022 1023
#
# 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
1024
# makefile but the argument can be passed to make if needed.
L
Linus Torvalds 已提交
1025 1026
#

1027
MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
L
Linus Torvalds 已提交
1028 1029
export MODLIB

1030
#
1031 1032 1033 1034
# INSTALL_MOD_STRIP, if defined, will cause modules to be
# stripped after they are installed.  If INSTALL_MOD_STRIP is '1', then
# the default option --strip-debug will be used.  Otherwise,
# INSTALL_MOD_STRIP value will be used as the options to the strip command.
1035

1036 1037
ifdef INSTALL_MOD_STRIP
ifeq ($(INSTALL_MOD_STRIP),1)
1038
mod_strip_cmd = $(STRIP) --strip-debug
1039
else
1040
mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
1041 1042
endif # INSTALL_MOD_STRIP=1
else
1043
mod_strip_cmd = true
1044 1045 1046
endif # INSTALL_MOD_STRIP
export mod_strip_cmd

1047 1048 1049 1050 1051 1052 1053
# CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
# after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
# or CONFIG_MODULE_COMPRESS_XZ.

mod_compress_cmd = true
ifdef CONFIG_MODULE_COMPRESS
  ifdef CONFIG_MODULE_COMPRESS_GZIP
1054
    mod_compress_cmd = $(KGZIP) -n -f
1055 1056
  endif # CONFIG_MODULE_COMPRESS_GZIP
  ifdef CONFIG_MODULE_COMPRESS_XZ
1057
    mod_compress_cmd = $(XZ) --lzma2=dict=2MiB -f
1058 1059 1060 1061
  endif # CONFIG_MODULE_COMPRESS_XZ
endif # CONFIG_MODULE_COMPRESS
export mod_compress_cmd

1062
ifdef CONFIG_MODULE_SIG_ALL
1063 1064 1065
$(eval $(call config_filename,MODULE_SIG_KEY))

mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
1066 1067 1068 1069 1070
else
mod_sign_cmd = true
endif
export mod_sign_cmd

1071 1072
HOST_LIBELF_LIBS = $(shell pkg-config libelf --libs 2>/dev/null || echo -lelf)

1073 1074 1075
has_libelf = $(call try-run,\
               echo "int main() {}" | $(HOSTCC) -xc -o /dev/null $(HOST_LIBELF_LIBS) -,1,0)

1076 1077 1078 1079 1080 1081 1082 1083 1084
ifdef CONFIG_STACK_VALIDATION
  ifeq ($(has_libelf),1)
    objtool_target := tools/objtool FORCE
  else
    SKIP_STACK_VALIDATION := 1
    export SKIP_STACK_VALIDATION
  endif
endif

1085
ifdef CONFIG_BPF
1086 1087 1088 1089 1090 1091
ifdef CONFIG_DEBUG_INFO_BTF
  ifeq ($(has_libelf),1)
    resolve_btfids_target := tools/bpf/resolve_btfids FORCE
  else
    ERROR_RESOLVE_BTFIDS := 1
  endif
1092 1093
endif # CONFIG_DEBUG_INFO_BTF
endif # CONFIG_BPF
1094

1095
PHONY += prepare0
1096

1097
export MODORDER := $(extmod-prefix)modules.order
1098
export MODULES_NSDEPS := $(extmod-prefix)modules.nsdeps
1099

L
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ifeq ($(KBUILD_EXTMOD),)
1101
core-y		+= kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
L
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1102

1103
vmlinux-dirs	:= $(patsubst %/,%,$(filter %/, \
L
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1104
		     $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
1105
		     $(libs-y) $(libs-m)))
L
Linus Torvalds 已提交
1106

1107
vmlinux-alldirs	:= $(sort $(vmlinux-dirs) Documentation \
1108
		     $(patsubst %/,%,$(filter %/, $(core-) \
1109
			$(drivers-) $(libs-))))
L
Linus Torvalds 已提交
1110

1111 1112 1113
subdir-modorder := $(addsuffix modules.order,$(filter %/, \
			$(core-y) $(core-m) $(libs-y) $(libs-m) \
			$(drivers-y) $(drivers-m)))
L
Linus Torvalds 已提交
1114

1115
build-dirs	:= $(vmlinux-dirs)
1116
clean-dirs	:= $(vmlinux-alldirs)
1117

1118 1119 1120
# 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)))
1121
ifdef CONFIG_MODULES
1122 1123
KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1124
else
1125
KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1126
endif
1127
KBUILD_VMLINUX_OBJS += $(patsubst %/,%/built-in.a, $(drivers-y))
L
Linus Torvalds 已提交
1128

1129
export KBUILD_VMLINUX_OBJS KBUILD_VMLINUX_LIBS
1130
export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1131
# used by scripts/Makefile.package
1132
export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) LICENSES arch include scripts tools)
1133

1134
vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
L
Linus Torvalds 已提交
1135

1136 1137
# Recurse until adjust_autoksyms.sh is satisfied
PHONY += autoksyms_recursive
1138
ifdef CONFIG_TRIM_UNUSED_KSYMS
1139 1140 1141
# 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)
1142 1143 1144 1145 1146
KBUILD_MODULES := 1

autoksyms_recursive: descend modules.order
	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
	  "$(MAKE) -f $(srctree)/Makefile vmlinux"
1147 1148
endif

1149 1150
autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)

1151 1152 1153 1154
quiet_cmd_autoksyms_h = GEN     $@
      cmd_autoksyms_h = mkdir -p $(dir $@); \
			$(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@

1155
$(autoksyms_h):
1156
	$(call cmd,autoksyms_h)
1157

1158 1159 1160
ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)

# Final link of vmlinux with optional arch pass after final link
1161
cmd_link-vmlinux =                                                 \
1162
	$(CONFIG_SHELL) $< "$(LD)" "$(KBUILD_LDFLAGS)" "$(LDFLAGS_vmlinux)";    \
1163
	$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1164

1165
vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1166
	+$(call if_changed,link-vmlinux)
1167

1168 1169
targets := vmlinux

1170
# The actual objects are generated when descending,
L
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1171
# make sure no implicit rule kicks in
1172
$(sort $(vmlinux-deps) $(subdir-modorder)): descend ;
L
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1173

1174
filechk_kernel.release = \
1175 1176
	echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"

G
Geert Uytterhoeven 已提交
1177
# Store (new) KERNELRELEASE string in include/config/kernel.release
1178
include/config/kernel.release: FORCE
1179
	$(call filechk,kernel.release)
1180

1181 1182 1183 1184
# Additional helpers built in scripts/
# Carefully list dependencies so we do not try to build scripts twice
# in parallel
PHONY += scripts
1185
scripts: scripts_basic scripts_dtc
1186
	$(Q)$(MAKE) $(build)=$(@)
1187

L
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1188
# Things we need to do before we recursively start building the kernel
1189 1190 1191 1192
# 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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M
Masahiro Yamada 已提交
1194
PHONY += prepare archprepare
1195

1196
archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1197 1198
	asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h \
	include/generated/autoconf.h
1199

1200
prepare0: archprepare
1201
	$(Q)$(MAKE) $(build)=scripts/mod
1202
	$(Q)$(MAKE) $(build)=.
1203

L
Linus Torvalds 已提交
1204
# All the preparing..
1205
prepare: prepare0 prepare-objtool prepare-resolve_btfids
1206

1207
# Support for using generic headers in asm-generic
1208 1209
asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj

1210 1211
PHONY += asm-generic uapi-asm-generic
asm-generic: uapi-asm-generic
1212 1213
	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
	generic=include/asm-generic
1214
uapi-asm-generic:
1215 1216
	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
	generic=include/uapi/asm-generic
1217

1218
PHONY += prepare-objtool prepare-resolve_btfids
1219
prepare-objtool: $(objtool_target)
1220 1221 1222 1223 1224 1225 1226 1227
ifeq ($(SKIP_STACK_VALIDATION),1)
ifdef CONFIG_UNWINDER_ORC
	@echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
	@false
else
	@echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
endif
endif
L
Linus Torvalds 已提交
1228

1229 1230 1231 1232 1233
prepare-resolve_btfids: $(resolve_btfids_target)
ifeq ($(ERROR_RESOLVE_BTFIDS),1)
	@echo "error: Cannot resolve BTF IDs for CONFIG_DEBUG_INFO_BTF, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
	@false
endif
L
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1234 1235 1236 1237 1238 1239 1240
# 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
1241 1242 1243 1244 1245
define filechk_utsrelease.h
	if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
	  exit 1;                                                         \
	fi;                                                               \
1246
	echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
S
Sam Ravnborg 已提交
1247
endef
L
Linus Torvalds 已提交
1248 1249

define filechk_version.h
S
Sasha Levin 已提交
1250 1251 1252 1253 1254 1255 1256 1257
	if [ $(SUBLEVEL) -gt 255 ]; then                                 \
		echo \#define LINUX_VERSION_CODE $(shell                 \
		expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 255); \
	else                                                             \
		echo \#define LINUX_VERSION_CODE $(shell                 \
		expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
	fi;                                                              \
	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
1258 1259 1260 1261
	((c) > 255 ? 255 : (c)))';                                       \
	echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
	echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
	echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
L
Linus Torvalds 已提交
1262 1263
endef

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 1305
headers_check:
	@:
1306

1307
ifdef CONFIG_HEADERS_INSTALL
1308
prepare: headers
1309
endif
1310

1311 1312 1313 1314
PHONY += scripts_unifdef
scripts_unifdef: scripts_basic
	$(Q)$(MAKE) $(build)=scripts scripts/unifdef

1315 1316 1317 1318 1319
# ---------------------------------------------------------------------------
# Kernel selftest

PHONY += kselftest
kselftest:
1320
	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1321

1322 1323
kselftest-%: FORCE
	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
W
Wang Long 已提交
1324

1325 1326 1327
PHONY += kselftest-merge
kselftest-merge:
	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1328 1329
	$(Q)find $(srctree)/tools/testing/selftests -name config | \
		xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1330
	$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1331

1332 1333 1334 1335 1336 1337 1338 1339 1340
# ---------------------------------------------------------------------------
# Devicetree files

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

ifneq ($(dtstree),)

M
Masahiro Yamada 已提交
1341
%.dtb: include/config/kernel.release scripts_dtc
1342 1343
	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@

1344
PHONY += dtbs dtbs_install dtbs_check
1345
dtbs: include/config/kernel.release scripts_dtc
1346 1347
	$(Q)$(MAKE) $(build)=$(dtstree)

1348
ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1349
export CHECK_DTBS=y
1350 1351 1352 1353
dtbs: dt_binding_check
endif

dtbs_check: dtbs
1354

1355
dtbs_install:
1356
	$(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367

ifdef CONFIG_OF_EARLY_FLATTREE
all: dtbs
endif

endif

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

1368 1369 1370 1371
ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
export CHECK_DT_BINDING=y
endif

1372
PHONY += dt_binding_check
1373 1374 1375
dt_binding_check: scripts_dtc
	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings

L
Linus Torvalds 已提交
1376 1377 1378 1379 1380
# ---------------------------------------------------------------------------
# Modules

ifdef CONFIG_MODULES

S
Sam Ravnborg 已提交
1381
# By default, build modules as well
L
Linus Torvalds 已提交
1382

1383
all: modules
L
Linus Torvalds 已提交
1384

1385 1386 1387 1388 1389 1390 1391
# 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

1392
# Build modules
T
Tejun Heo 已提交
1393
#
1394 1395 1396
# 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
1397

1398
PHONY += modules
1399
modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_check modules_prepare
S
Sam Ravnborg 已提交
1400
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
L
Linus Torvalds 已提交
1401

1402 1403 1404
PHONY += modules_check
modules_check: modules.order
	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
L
Linus Torvalds 已提交
1405

1406 1407 1408 1409 1410 1411
cmd_modules_order = $(AWK) '!x[$$0]++' $(real-prereqs) > $@

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

targets += modules.order
1412

L
Linus Torvalds 已提交
1413
# Target to prepare building external modules
1414
PHONY += modules_prepare
1415
modules_prepare: prepare
1416
	$(Q)$(MAKE) $(build)=scripts scripts/module.lds
L
Linus Torvalds 已提交
1417 1418

# Target to install modules
1419
PHONY += modules_install
L
Linus Torvalds 已提交
1420 1421
modules_install: _modinst_ _modinst_post

1422
PHONY += _modinst_
1423
_modinst_:
L
Linus Torvalds 已提交
1424 1425 1426
	@rm -rf $(MODLIB)/kernel
	@rm -f $(MODLIB)/source
	@mkdir -p $(MODLIB)/kernel
1427
	@ln -s $(abspath $(srctree)) $(MODLIB)/source
L
Linus Torvalds 已提交
1428 1429
	@if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
		rm -f $(MODLIB)/build ; \
1430
		ln -s $(CURDIR) $(MODLIB)/build ; \
L
Linus Torvalds 已提交
1431
	fi
1432
	@sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order
1433 1434
	@cp -f modules.builtin $(MODLIB)/
	@cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
S
Sam Ravnborg 已提交
1435
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
L
Linus Torvalds 已提交
1436

1437
# This depmod is only for convenience to give the initial
L
Linus Torvalds 已提交
1438 1439
# boot a modules.dep even before / is mounted read-write.  However the
# boot script depmod is the master version.
1440
PHONY += _modinst_post
1441
_modinst_post: _modinst_
1442
	$(call cmd,depmod)
L
Linus Torvalds 已提交
1443

J
Josh Boyer 已提交
1444 1445 1446 1447 1448 1449
ifeq ($(CONFIG_MODULE_SIG), y)
PHONY += modules_sign
modules_sign:
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
endif

L
Linus Torvalds 已提交
1450 1451 1452 1453 1454
else # CONFIG_MODULES

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

1455 1456
PHONY += modules modules_install
modules modules_install:
M
Michal Marek 已提交
1457 1458 1459 1460 1461
	@echo >&2
	@echo >&2 "The present kernel configuration has modules disabled."
	@echo >&2 "Type 'make config' and enable loadable module support."
	@echo >&2 "Then build a kernel with module support enabled."
	@echo >&2
L
Linus Torvalds 已提交
1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473
	@exit 1

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'
1474
CLEAN_FILES += include/ksym vmlinux.symvers \
1475 1476
	       modules.builtin modules.builtin.modinfo modules.nsdeps \
	       compile_commands.json
L
Linus Torvalds 已提交
1477 1478

# Directories & files removed with 'make mrproper'
1479
MRPROPER_FILES += include/config include/generated          \
1480
		  arch/$(SRCARCH)/include/generated .tmp_objdiff \
1481 1482
		  debian snap tar-install \
		  .config .config.old .version \
1483
		  Module.symvers \
1484 1485
		  signing_key.pem signing_key.priv signing_key.x509	\
		  x509.genkey extra_certificates signing_key.x509.keyid	\
1486 1487
		  signing_key.x509.signer vmlinux-gdb.py \
		  *.spec
L
Linus Torvalds 已提交
1488

1489 1490 1491
# Directories & files removed with 'make distclean'
DISTCLEAN_FILES += tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS

L
Linus Torvalds 已提交
1492 1493 1494 1495
# clean - Delete most, but leave enough to build external modules
#
clean: rm-files := $(CLEAN_FILES)

1496
PHONY += archclean vmlinuxclean
L
Linus Torvalds 已提交
1497

1498 1499
vmlinuxclean:
	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1500
	$(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1501 1502

clean: archclean vmlinuxclean
L
Linus Torvalds 已提交
1503 1504 1505 1506

# mrproper - Delete all generated files, including .config
#
mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1507
mrproper-dirs      := $(addprefix _mrproper_,scripts)
L
Linus Torvalds 已提交
1508

1509
PHONY += $(mrproper-dirs) mrproper
L
Linus Torvalds 已提交
1510 1511 1512
$(mrproper-dirs):
	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)

1513
mrproper: clean $(mrproper-dirs)
L
Linus Torvalds 已提交
1514 1515 1516 1517
	$(call cmd,rmfiles)

# distclean
#
1518 1519
distclean: rm-files := $(wildcard $(DISTCLEAN_FILES))

1520
PHONY += distclean
L
Linus Torvalds 已提交
1521 1522

distclean: mrproper
1523
	$(call cmd,rmfiles)
L
Linus Torvalds 已提交
1524
	@find $(srctree) $(RCS_FIND_IGNORE) \
S
Sam Ravnborg 已提交
1525
		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1526 1527
		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
		-o -name 'core' \) \
L
Linus Torvalds 已提交
1528 1529 1530 1531 1532 1533
		-type f -print | xargs rm -f


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

1534
%src-pkg: FORCE
1535
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1536
%pkg: include/config/kernel.release FORCE
1537
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
L
Linus Torvalds 已提交
1538 1539 1540 1541

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

1542
boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1543
boards := $(sort $(notdir $(boards)))
1544 1545
board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
board-dirs := $(sort $(notdir $(board-dirs:/=)))
L
Linus Torvalds 已提交
1546

1547
PHONY += help
L
Linus Torvalds 已提交
1548 1549
help:
	@echo  'Cleaning targets:'
1550
	@echo  '  clean		  - Remove most generated files but keep the config and'
1551
	@echo  '                    enough build support to build external modules'
1552
	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
1553
	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
L
Linus Torvalds 已提交
1554 1555 1556 1557 1558 1559 1560 1561
	@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'
1562
	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
L
Linus Torvalds 已提交
1563
	@echo  '  dir/            - Build all files in dir and below'
1564
	@echo  '  dir/file.[ois]  - Build specified target only'
1565 1566
	@echo  '  dir/file.ll     - Build the LLVM assembly file'
	@echo  '                    (requires compiler support for LLVM assembly generation)'
1567 1568
	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
	@echo  '                    (requires a recent binutils and recent build (System.map))'
1569
	@echo  '  dir/file.ko     - Build module including final link'
1570
	@echo  '  modules_prepare - Set up for building external modules'
L
Linus Torvalds 已提交
1571 1572
	@echo  '  tags/TAGS	  - Generate tags file for editors'
	@echo  '  cscope	  - Generate cscope index'
1573
	@echo  '  gtags           - Generate GNU GLOBAL index'
1574 1575 1576
	@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)'
1577
	@echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1578
	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1579
	 echo  ''
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	@echo  'Static analysers:'
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	@echo  '  checkstack      - Generate a list of stack hogs'
1582
	@echo  '  versioncheck    - Sanity check on version.h usage'
1583
	@echo  '  includecheck    - Check for duplicate included header files'
1584
	@echo  '  export_report   - List the usages of all exported symbols'
1585
	@echo  '  headerdep       - Detect inclusion cycles in headers'
1586
	@echo  '  coccicheck      - Check with Coccinelle'
1587 1588
	@echo  '  clang-analyzer  - Check with clang static analyzer'
	@echo  '  clang-tidy      - Check with clang-tidy'
1589
	@echo  ''
1590 1591 1592
	@echo  'Tools:'
	@echo  '  nsdeps          - Generate missing symbol namespace dependencies'
	@echo  ''
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	@echo  'Kernel selftest:'
1594 1595 1596 1597 1598 1599 1600 1601 1602
	@echo  '  kselftest         - Build and run kernel selftest'
	@echo  '                      Build, install, and boot kernel before'
	@echo  '                      running kselftest on it'
	@echo  '                      Run as root for full coverage'
	@echo  '  kselftest-all     - Build kernel selftest'
	@echo  '  kselftest-install - Build and install kernel selftest'
	@echo  '  kselftest-clean   - Remove all generated kselftest files'
	@echo  '  kselftest-merge   - Merge all the config dependencies of'
	@echo  '		      kselftest to existing .config.'
1603
	@echo  ''
1604 1605
	@$(if $(dtstree), \
		echo 'Devicetree:'; \
1606 1607 1608 1609
		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';\
1610 1611
		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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1616
	@echo  'Kernel packaging:'
1617
	@$(MAKE) -f $(srctree)/scripts/Makefile.package help
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1618 1619
	@echo  ''
	@echo  'Documentation targets:'
1620
	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
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1621
	@echo  ''
1622
	@echo  'Architecture specific targets ($(SRCARCH)):'
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1623
	@$(if $(archhelp),$(archhelp),\
1624
		echo '  No architecture specific help defined for $(SRCARCH)')
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1625 1626 1627
	@echo  ''
	@$(if $(boards), \
		$(foreach b, $(boards), \
1628
		printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
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		echo '')
1630 1631 1632 1633 1634
	@$(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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	@echo  '  make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1637
	@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'
1639 1640
	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
	@echo  '                       (sparse by default)'
1641
	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1642
	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1643
	@echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
1644 1645 1646
	@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'
1647
	@echo  '		Multiple levels can be combined with W=12 or W=123'
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1648 1649 1650 1651 1652
	@echo  ''
	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
	@echo  'For further info see the ./README file'


1653 1654 1655 1656
help-board-dirs := $(addprefix help-,$(board-dirs))

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

1657
boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1658 1659 1660 1661 1662 1663 1664 1665 1666

$(help-board-dirs): help-%:
	@echo  'Architecture specific targets ($(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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# Documentation targets
# ---------------------------------------------------------------------------
1669 1670
DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
	       linkcheckdocs dochelp refcheckdocs
1671
PHONY += $(DOC_TARGETS)
1672
$(DOC_TARGETS):
1673
	$(Q)$(MAKE) $(build)=Documentation $@
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1675 1676 1677 1678
# Misc
# ---------------------------------------------------------------------------

PHONY += scripts_gdb
1679
scripts_gdb: prepare0
1680
	$(Q)$(MAKE) $(build)=scripts/gdb
1681
	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1682 1683 1684 1685 1686

ifdef CONFIG_GDB_SCRIPTS
all: scripts_gdb
endif

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1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702
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
# in the basis kernel ordinary make commands (without M=...) must
# be used.
#
# The following are the only valid targets when building external
# modules.
# make M=dir clean     Delete all automatically generated files
# make M=dir modules   Make all modules in specified dir
# make M=dir	       Same as 'make M=dir modules'
# make M=dir modules_install
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#                      Install the modules built in the module directory
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1704 1705
#                      Assumes install directory is already created

1706 1707
# We are always building only modules.
KBUILD_BUILTIN :=
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1708 1709
KBUILD_MODULES := 1

1710 1711
build-dirs := $(KBUILD_EXTMOD)
PHONY += modules
1712
modules: $(MODORDER)
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1713
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
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1714

1715 1716 1717
$(MODORDER): descend
	@:

1718
PHONY += modules_install
1719
modules_install: _emodinst_ _emodinst_post
1720

1721 1722
install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
PHONY += _emodinst_
1723 1724
_emodinst_:
	$(Q)mkdir -p $(MODLIB)/$(install-dir)
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1725
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
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1726

1727
PHONY += _emodinst_post
1728 1729 1730
_emodinst_post: _emodinst_
	$(call cmd,depmod)

1731 1732 1733
compile_commands.json: $(extmod-prefix)compile_commands.json
PHONY += compile_commands.json

1734
clean-dirs := $(KBUILD_EXTMOD)
1735 1736
clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
	$(KBUILD_EXTMOD)/compile_commands.json
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1737

1738
PHONY += help
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1739 1740 1741 1742 1743 1744 1745 1746
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  ''
1747

1748 1749 1750
# no-op for external module builds
PHONY += prepare modules_prepare

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1751 1752
endif # KBUILD_EXTMOD

1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782
# 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
1783
single_modpost: $(single-no-ko) modules_prepare
1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796
	$(Q){ $(foreach m, $(single-ko), echo $(extmod-prefix)$m;) } > $(MODORDER)
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost

KBUILD_MODULES := 1

export KBUILD_SINGLE_TARGETS := $(addprefix $(extmod-prefix), $(single-no-ko))

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

endif

1797 1798 1799 1800
ifndef CONFIG_MODULES
KBUILD_MODULES :=
endif

1801 1802 1803 1804 1805 1806 1807 1808
# 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
1809
	$(Q)$(MAKE) $(build)=$@ \
1810
	single-build=$(if $(filter-out $@/, $(filter $@/%, $(KBUILD_SINGLE_TARGETS))),1) \
1811
	need-builtin=1 need-modorder=1
1812

1813 1814 1815 1816 1817
clean-dirs := $(addprefix _clean_, $(clean-dirs))
PHONY += $(clean-dirs) clean
$(clean-dirs):
	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)

1818 1819
clean: $(clean-dirs)
	$(call cmd,rmfiles)
1820
	@find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1821
		\( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1822 1823
		-o -name '*.ko.*' \
		-o -name '*.dtb' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1824
		-o -name '*.dwo' -o -name '*.lst' \
1825
		-o -name '*.su' -o -name '*.mod' \
1826
		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1827
		-o -name '*.lex.c' -o -name '*.tab.[ch]' \
1828
		-o -name '*.asn1.[ch]' \
1829
		-o -name '*.symtypes' -o -name 'modules.order' \
1830
		-o -name '.tmp_*.o.*' \
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		-o -name '*.c.[012]*.*' \
1832
		-o -name '*.ll' \
1833 1834
		-o -name '*.gcno' \) -type f -print | xargs rm -f

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# Generate tags for editors
# ---------------------------------------------------------------------------
1837
quiet_cmd_tags = GEN     $@
1838
      cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
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1839

1840
tags TAGS cscope gtags: FORCE
L
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1841 1842
	$(call cmd,tags)

1843 1844 1845 1846
# Script to generate missing namespace dependencies
# ---------------------------------------------------------------------------

PHONY += nsdeps
1847
nsdeps: export KBUILD_NSDEPS=1
1848
nsdeps: modules
1849
	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1850

1851 1852 1853 1854 1855 1856
# Clang Tooling
# ---------------------------------------------------------------------------

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

1857
$(extmod-prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
1858 1859 1860 1861 1862 1863
	$(if $(KBUILD_EXTMOD),,$(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)) \
	$(if $(CONFIG_MODULES), $(MODORDER)) FORCE
	$(call if_changed,gen_compile_commands)

targets += $(extmod-prefix)compile_commands.json

1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877
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 $@ $<

clang-tidy clang-analyzer: $(extmod-prefix)compile_commands.json
	$(call cmd,clang_tools)
else
clang-tidy clang-analyzer:
	@echo "$@ requires CC=clang" >&2
	@false
endif

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1878 1879 1880
# Scripts to check various things for consistency
# ---------------------------------------------------------------------------

J
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1881
PHONY += includecheck versioncheck coccicheck export_report
P
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1882

L
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1883
includecheck:
1884
	find $(srctree)/* $(RCS_FIND_IGNORE) \
L
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1885
		-name '*.[hcS]' -type f -print | sort \
1886
		| xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
L
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1887 1888

versioncheck:
1889
	find $(srctree)/* $(RCS_FIND_IGNORE) \
L
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1890
		-name '*.[hcS]' -type f -print | sort \
1891
		| xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
L
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1892

1893
coccicheck:
1894
	$(Q)$(BASH) $(srctree)/scripts/$@
1895

1896 1897 1898
export_report:
	$(PERL) $(srctree)/scripts/export_report.pl

1899
PHONY += checkstack kernelrelease kernelversion image_name
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1900

J
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1901 1902 1903 1904 1905 1906 1907 1908 1909
# 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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1910 1911
checkstack:
	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1912
	$(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
L
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1913

1914 1915
kernelrelease:
	@echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1916

1917
kernelversion:
1918
	@echo $(KERNELVERSION)
L
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1919

1920 1921 1922
image_name:
	@echo $(KBUILD_IMAGE)

1923
# Clear a bunch of variables before executing the submake
1924 1925 1926 1927 1928

ifeq ($(quiet),silent_)
tools_silent=s
endif

1929
tools/: FORCE
1930
	$(Q)mkdir -p $(objtree)/tools
1931
	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1932 1933

tools/%: FORCE
1934
	$(Q)mkdir -p $(objtree)/tools
1935
	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1936

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1937
quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
1938
      cmd_rmfiles = rm -rf $(rm-files)
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1939

1940
# Run depmod only if we have System.map and depmod is executable
1941
quiet_cmd_depmod = DEPMOD  $(KERNELRELEASE)
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1942
      cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1943
                   $(KERNELRELEASE)
1944

1945 1946
# read saved command lines for existing targets
existing-targets := $(wildcard $(sort $(targets)))
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1947

1948
-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
L
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1949

1950
endif # config-build
1951 1952
endif # mixed-build
endif # need-sub-make
L
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1953

1954
PHONY += FORCE
L
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1955
FORCE:
1956

1957
# Declare the contents of the PHONY variable as phony.  We keep that
1958
# information in a variable so we can use it in if_changed and friends.
1959
.PHONY: $(PHONY)