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   1# SPDX-License-Identifier: GPL-2.0
   2VERSION = 5
   3PATCHLEVEL = 10
   4SUBLEVEL = 0
   5EXTRAVERSION =
   6NAME = Kleptomaniac Octopus
   7
   8# *DOCUMENTATION*
   9# To see a list of typical targets execute "make help"
  10# More info can be located in ./README
  11# Comments in this file are targeted only to the developer, do not
  12# expect to learn how to build the kernel reading this file.
  13
  14$(if $(filter __%, $(MAKECMDGOALS)), \
  15        $(error targets prefixed with '__' are only for internal use))
  16
  17# That's our default target when none is given on the command line
  18PHONY := __all
  19__all:
  20
  21# We are using a recursive build, so we need to do a little thinking
  22# to get the ordering right.
  23#
  24# Most importantly: sub-Makefiles should only ever modify files in
  25# their own directory. If in some directory we have a dependency on
  26# a file in another dir (which doesn't happen often, but it's often
  27# unavoidable when linking the built-in.a targets which finally
  28# turn into vmlinux), we will call a sub make in that other dir, and
  29# after that we are sure that everything which is in that other dir
  30# is now up to date.
  31#
  32# The only cases where we need to modify files which have global
  33# effects are thus separated out and done before the recursive
  34# descending is started. They are now explicitly listed as the
  35# prepare rule.
  36
  37ifneq ($(sub_make_done),1)
  38
  39# Do not use make's built-in rules and variables
  40# (this increases performance and avoids hard-to-debug behaviour)
  41MAKEFLAGS += -rR
  42
  43# Avoid funny character set dependencies
  44unexport LC_ALL
  45LC_COLLATE=C
  46LC_NUMERIC=C
  47export LC_COLLATE LC_NUMERIC
  48
  49# Avoid interference with shell env settings
  50unexport GREP_OPTIONS
  51
  52# Beautify output
  53# ---------------------------------------------------------------------------
  54#
  55# Normally, we echo the whole command before executing it. By making
  56# that echo $($(quiet)$(cmd)), we now have the possibility to set
  57# $(quiet) to choose other forms of output instead, e.g.
  58#
  59#         quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
  60#         cmd_cc_o_c       = $(CC) $(c_flags) -c -o $@ $<
  61#
  62# If $(quiet) is empty, the whole command will be printed.
  63# If it is set to "quiet_", only the short version will be printed.
  64# If it is set to "silent_", nothing will be printed at all, since
  65# the variable $(silent_cmd_cc_o_c) doesn't exist.
  66#
  67# A simple variant is to prefix commands with $(Q) - that's useful
  68# for commands that shall be hidden in non-verbose mode.
  69#
  70#       $(Q)ln $@ :<
  71#
  72# If KBUILD_VERBOSE equals 0 then the above command will be hidden.
  73# If KBUILD_VERBOSE equals 1 then the above command is displayed.
  74# If KBUILD_VERBOSE equals 2 then give the reason why each target is rebuilt.
  75#
  76# To put more focus on warnings, be less verbose as default
  77# Use 'make V=1' to see the full commands
  78
  79ifeq ("$(origin V)", "command line")
  80  KBUILD_VERBOSE = $(V)
  81endif
  82ifndef KBUILD_VERBOSE
  83  KBUILD_VERBOSE = 0
  84endif
  85
  86ifeq ($(KBUILD_VERBOSE),1)
  87  quiet =
  88  Q =
  89else
  90  quiet=quiet_
  91  Q = @
  92endif
  93
  94# If the user is running make -s (silent mode), suppress echoing of
  95# commands
  96
  97ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
  98  quiet=silent_
  99endif
 100
 101export quiet Q KBUILD_VERBOSE
 102
 103# Kbuild will save output files in the current working directory.
 104# This does not need to match to the root of the kernel source tree.
 105#
 106# For example, you can do this:
 107#
 108#  cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
 109#
 110# If you want to save output files in a different location, there are
 111# two syntaxes to specify it.
 112#
 113# 1) O=
 114# Use "make O=dir/to/store/output/files/"
 115#
 116# 2) Set KBUILD_OUTPUT
 117# Set the environment variable KBUILD_OUTPUT to point to the output directory.
 118# export KBUILD_OUTPUT=dir/to/store/output/files/; make
 119#
 120# The O= assignment takes precedence over the KBUILD_OUTPUT environment
 121# variable.
 122
 123# Do we want to change the working directory?
 124ifeq ("$(origin O)", "command line")
 125  KBUILD_OUTPUT := $(O)
 126endif
 127
 128ifneq ($(KBUILD_OUTPUT),)
 129# Make's built-in functions such as $(abspath ...), $(realpath ...) cannot
 130# expand a shell special character '~'. We use a somewhat tedious way here.
 131abs_objtree := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) && pwd)
 132$(if $(abs_objtree),, \
 133     $(error failed to create output directory "$(KBUILD_OUTPUT)"))
 134
 135# $(realpath ...) resolves symlinks
 136abs_objtree := $(realpath $(abs_objtree))
 137else
 138abs_objtree := $(CURDIR)
 139endif # ifneq ($(KBUILD_OUTPUT),)
 140
 141ifeq ($(abs_objtree),$(CURDIR))
 142# Suppress "Entering directory ..." unless we are changing the work directory.
 143MAKEFLAGS += --no-print-directory
 144else
 145need-sub-make := 1
 146endif
 147
 148abs_srctree := $(realpath $(dir $(lastword $(MAKEFILE_LIST))))
 149
 150ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
 151$(error source directory cannot contain spaces or colons)
 152endif
 153
 154ifneq ($(abs_srctree),$(abs_objtree))
 155# Look for make include files relative to root of kernel src
 156#
 157# This does not become effective immediately because MAKEFLAGS is re-parsed
 158# once after the Makefile is read. We need to invoke sub-make.
 159MAKEFLAGS += --include-dir=$(abs_srctree)
 160need-sub-make := 1
 161endif
 162
 163this-makefile := $(lastword $(MAKEFILE_LIST))
 164
 165ifneq ($(filter 3.%,$(MAKE_VERSION)),)
 166# 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
 167# We need to invoke sub-make to avoid implicit rules in the top Makefile.
 168need-sub-make := 1
 169# Cancel implicit rules for this Makefile.
 170$(this-makefile): ;
 171endif
 172
 173export abs_srctree abs_objtree
 174export sub_make_done := 1
 175
 176ifeq ($(need-sub-make),1)
 177
 178PHONY += $(MAKECMDGOALS) __sub-make
 179
 180$(filter-out $(this-makefile), $(MAKECMDGOALS)) __all: __sub-make
 181        @:
 182
 183# Invoke a second make in the output directory, passing relevant variables
 184__sub-make:
 185        $(Q)$(MAKE) -C $(abs_objtree) -f $(abs_srctree)/Makefile $(MAKECMDGOALS)
 186
 187endif # need-sub-make
 188endif # sub_make_done
 189
 190# We process the rest of the Makefile if this is the final invocation of make
 191ifeq ($(need-sub-make),)
 192
 193# Do not print "Entering directory ...",
 194# but we want to display it when entering to the output directory
 195# so that IDEs/editors are able to understand relative filenames.
 196MAKEFLAGS += --no-print-directory
 197
 198# Call a source code checker (by default, "sparse") as part of the
 199# C compilation.
 200#
 201# Use 'make C=1' to enable checking of only re-compiled files.
 202# Use 'make C=2' to enable checking of *all* source files, regardless
 203# of whether they are re-compiled or not.
 204#
 205# See the file "Documentation/dev-tools/sparse.rst" for more details,
 206# including where to get the "sparse" utility.
 207
 208ifeq ("$(origin C)", "command line")
 209  KBUILD_CHECKSRC = $(C)
 210endif
 211ifndef KBUILD_CHECKSRC
 212  KBUILD_CHECKSRC = 0
 213endif
 214
 215# Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
 216# directory of external module to build. Setting M= takes precedence.
 217ifeq ("$(origin M)", "command line")
 218  KBUILD_EXTMOD := $(M)
 219endif
 220
 221$(if $(word 2, $(KBUILD_EXTMOD)), \
 222        $(error building multiple external modules is not supported))
 223
 224export KBUILD_CHECKSRC KBUILD_EXTMOD
 225
 226extmod-prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
 227
 228ifeq ($(abs_srctree),$(abs_objtree))
 229        # building in the source tree
 230        srctree := .
 231        building_out_of_srctree :=
 232else
 233        ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
 234                # building in a subdirectory of the source tree
 235                srctree := ..
 236        else
 237                srctree := $(abs_srctree)
 238        endif
 239        building_out_of_srctree := 1
 240endif
 241
 242ifneq ($(KBUILD_ABS_SRCTREE),)
 243srctree := $(abs_srctree)
 244endif
 245
 246objtree         := .
 247VPATH           := $(srctree)
 248
 249export building_out_of_srctree srctree objtree VPATH
 250
 251# To make sure we do not include .config for any of the *config targets
 252# catch them early, and hand them over to scripts/kconfig/Makefile
 253# It is allowed to specify more targets when calling make, including
 254# mixing *config targets and build targets.
 255# For example 'make oldconfig all'.
 256# Detect when mixed targets is specified, and make a second invocation
 257# of make so .config is not included in this case either (for *config).
 258
 259version_h := include/generated/uapi/linux/version.h
 260old_version_h := include/linux/version.h
 261
 262clean-targets := %clean mrproper cleandocs
 263no-dot-config-targets := $(clean-targets) \
 264                         cscope gtags TAGS tags help% %docs check% coccicheck \
 265                         $(version_h) headers headers_% archheaders archscripts \
 266                         %asm-generic kernelversion %src-pkg dt_binding_check \
 267                         outputmakefile
 268no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease
 269single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
 270
 271config-build    :=
 272mixed-build     :=
 273need-config     := 1
 274may-sync-config := 1
 275single-build    :=
 276
 277ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
 278        ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
 279                need-config :=
 280        endif
 281endif
 282
 283ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
 284        ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
 285                may-sync-config :=
 286        endif
 287endif
 288
 289ifneq ($(KBUILD_EXTMOD),)
 290        may-sync-config :=
 291endif
 292
 293ifeq ($(KBUILD_EXTMOD),)
 294        ifneq ($(filter %config,$(MAKECMDGOALS)),)
 295                config-build := 1
 296                ifneq ($(words $(MAKECMDGOALS)),1)
 297                        mixed-build := 1
 298                endif
 299        endif
 300endif
 301
 302# We cannot build single targets and the others at the same time
 303ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
 304        single-build := 1
 305        ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
 306                mixed-build := 1
 307        endif
 308endif
 309
 310# For "make -j clean all", "make -j mrproper defconfig all", etc.
 311ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
 312        ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
 313                mixed-build := 1
 314        endif
 315endif
 316
 317# install and modules_install need also be processed one by one
 318ifneq ($(filter install,$(MAKECMDGOALS)),)
 319        ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
 320                mixed-build := 1
 321        endif
 322endif
 323
 324ifdef mixed-build
 325# ===========================================================================
 326# We're called with mixed targets (*config and build targets).
 327# Handle them one by one.
 328
 329PHONY += $(MAKECMDGOALS) __build_one_by_one
 330
 331$(MAKECMDGOALS): __build_one_by_one
 332        @:
 333
 334__build_one_by_one:
 335        $(Q)set -e; \
 336        for i in $(MAKECMDGOALS); do \
 337                $(MAKE) -f $(srctree)/Makefile $$i; \
 338        done
 339
 340else # !mixed-build
 341
 342include scripts/Kbuild.include
 343
 344# Read KERNELRELEASE from include/config/kernel.release (if it exists)
 345KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
 346KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
 347export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
 348
 349include scripts/subarch.include
 350
 351# Cross compiling and selecting different set of gcc/bin-utils
 352# ---------------------------------------------------------------------------
 353#
 354# When performing cross compilation for other architectures ARCH shall be set
 355# to the target architecture. (See arch/* for the possibilities).
 356# ARCH can be set during invocation of make:
 357# make ARCH=ia64
 358# Another way is to have ARCH set in the environment.
 359# The default ARCH is the host where make is executed.
 360
 361# CROSS_COMPILE specify the prefix used for all executables used
 362# during compilation. Only gcc and related bin-utils executables
 363# are prefixed with $(CROSS_COMPILE).
 364# CROSS_COMPILE can be set on the command line
 365# make CROSS_COMPILE=ia64-linux-
 366# Alternatively CROSS_COMPILE can be set in the environment.
 367# Default value for CROSS_COMPILE is not to prefix executables
 368# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
 369ARCH            ?= $(SUBARCH)
 370
 371# Architecture as present in compile.h
 372UTS_MACHINE     := $(ARCH)
 373SRCARCH         := $(ARCH)
 374
 375# Additional ARCH settings for x86
 376ifeq ($(ARCH),i386)
 377        SRCARCH := x86
 378endif
 379ifeq ($(ARCH),x86_64)
 380        SRCARCH := x86
 381endif
 382
 383# Additional ARCH settings for sparc
 384ifeq ($(ARCH),sparc32)
 385       SRCARCH := sparc
 386endif
 387ifeq ($(ARCH),sparc64)
 388       SRCARCH := sparc
 389endif
 390
 391# Additional ARCH settings for sh
 392ifeq ($(ARCH),sh64)
 393       SRCARCH := sh
 394endif
 395
 396KCONFIG_CONFIG  ?= .config
 397export KCONFIG_CONFIG
 398
 399# Default file for 'make defconfig'. This may be overridden by arch-Makefile.
 400export KBUILD_DEFCONFIG := defconfig
 401
 402# SHELL used by kbuild
 403CONFIG_SHELL := sh
 404
 405HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
 406HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
 407HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
 408
 409ifneq ($(LLVM),)
 410HOSTCC  = clang
 411HOSTCXX = clang++
 412else
 413HOSTCC  = gcc
 414HOSTCXX = g++
 415endif
 416
 417export KBUILD_USERCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
 418                              -O2 -fomit-frame-pointer -std=gnu89
 419export KBUILD_USERLDFLAGS :=
 420
 421KBUILD_HOSTCFLAGS   := $(KBUILD_USERCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
 422KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
 423KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
 424KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
 425
 426# Make variables (CC, etc...)
 427CPP             = $(CC) -E
 428ifneq ($(LLVM),)
 429CC              = clang
 430LD              = ld.lld
 431AR              = llvm-ar
 432NM              = llvm-nm
 433OBJCOPY         = llvm-objcopy
 434OBJDUMP         = llvm-objdump
 435READELF         = llvm-readelf
 436STRIP           = llvm-strip
 437else
 438CC              = $(CROSS_COMPILE)gcc
 439LD              = $(CROSS_COMPILE)ld
 440AR              = $(CROSS_COMPILE)ar
 441NM              = $(CROSS_COMPILE)nm
 442OBJCOPY         = $(CROSS_COMPILE)objcopy
 443OBJDUMP         = $(CROSS_COMPILE)objdump
 444READELF         = $(CROSS_COMPILE)readelf
 445STRIP           = $(CROSS_COMPILE)strip
 446endif
 447PAHOLE          = pahole
 448RESOLVE_BTFIDS  = $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
 449LEX             = flex
 450YACC            = bison
 451AWK             = awk
 452INSTALLKERNEL  := installkernel
 453DEPMOD          = /sbin/depmod
 454PERL            = perl
 455PYTHON          = python
 456PYTHON3         = python3
 457CHECK           = sparse
 458BASH            = bash
 459KGZIP           = gzip
 460KBZIP2          = bzip2
 461KLZOP           = lzop
 462LZMA            = lzma
 463LZ4             = lz4c
 464XZ              = xz
 465ZSTD            = zstd
 466
 467CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
 468                  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
 469NOSTDINC_FLAGS :=
 470CFLAGS_MODULE   =
 471AFLAGS_MODULE   =
 472LDFLAGS_MODULE  =
 473CFLAGS_KERNEL   =
 474AFLAGS_KERNEL   =
 475LDFLAGS_vmlinux =
 476
 477# Use USERINCLUDE when you must reference the UAPI directories only.
 478USERINCLUDE    := \
 479                -I$(srctree)/arch/$(SRCARCH)/include/uapi \
 480                -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
 481                -I$(srctree)/include/uapi \
 482                -I$(objtree)/include/generated/uapi \
 483                -include $(srctree)/include/linux/kconfig.h
 484
 485# Use LINUXINCLUDE when you must reference the include/ directory.
 486# Needed to be compatible with the O= option
 487LINUXINCLUDE    := \
 488                -I$(srctree)/arch/$(SRCARCH)/include \
 489                -I$(objtree)/arch/$(SRCARCH)/include/generated \
 490                $(if $(building_out_of_srctree),-I$(srctree)/include) \
 491                -I$(objtree)/include \
 492                $(USERINCLUDE)
 493
 494KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
 495KBUILD_CFLAGS   := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
 496                   -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
 497                   -Werror=implicit-function-declaration -Werror=implicit-int \
 498                   -Werror=return-type -Wno-format-security \
 499                   -std=gnu89
 500KBUILD_CPPFLAGS := -D__KERNEL__
 501KBUILD_AFLAGS_KERNEL :=
 502KBUILD_CFLAGS_KERNEL :=
 503KBUILD_AFLAGS_MODULE  := -DMODULE
 504KBUILD_CFLAGS_MODULE  := -DMODULE
 505KBUILD_LDFLAGS_MODULE :=
 506KBUILD_LDFLAGS :=
 507CLANG_FLAGS :=
 508
 509export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC
 510export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
 511export PERL PYTHON PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
 512export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
 513export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
 514
 515export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
 516export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
 517export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
 518export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
 519export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
 520
 521# Files to ignore in find ... statements
 522
 523export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
 524                          -name CVS -o -name .pc -o -name .hg -o -name .git \) \
 525                          -prune -o
 526export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
 527                         --exclude CVS --exclude .pc --exclude .hg --exclude .git
 528
 529# ===========================================================================
 530# Rules shared between *config targets and build targets
 531
 532# Basic helpers built in scripts/basic/
 533PHONY += scripts_basic
 534scripts_basic:
 535        $(Q)$(MAKE) $(build)=scripts/basic
 536        $(Q)rm -f .tmp_quiet_recordmcount
 537
 538PHONY += outputmakefile
 539# Before starting out-of-tree build, make sure the source tree is clean.
 540# outputmakefile generates a Makefile in the output directory, if using a
 541# separate output directory. This allows convenient use of make in the
 542# output directory.
 543# At the same time when output Makefile generated, generate .gitignore to
 544# ignore whole output directory
 545outputmakefile:
 546ifdef building_out_of_srctree
 547        $(Q)if [ -f $(srctree)/.config -o \
 548                 -d $(srctree)/include/config -o \
 549                 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
 550                echo >&2 "***"; \
 551                echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
 552                echo >&2 "*** in $(abs_srctree)";\
 553                echo >&2 "***"; \
 554                false; \
 555        fi
 556        $(Q)ln -fsn $(srctree) source
 557        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile $(srctree)
 558        $(Q)test -e .gitignore || \
 559        { echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
 560endif
 561
 562ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),)
 563ifneq ($(CROSS_COMPILE),)
 564CLANG_FLAGS     += --target=$(notdir $(CROSS_COMPILE:%-=%))
 565GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
 566CLANG_FLAGS     += --prefix=$(GCC_TOOLCHAIN_DIR)$(notdir $(CROSS_COMPILE))
 567GCC_TOOLCHAIN   := $(realpath $(GCC_TOOLCHAIN_DIR)/..)
 568endif
 569ifneq ($(GCC_TOOLCHAIN),)
 570CLANG_FLAGS     += --gcc-toolchain=$(GCC_TOOLCHAIN)
 571endif
 572ifneq ($(LLVM_IAS),1)
 573CLANG_FLAGS     += -no-integrated-as
 574endif
 575CLANG_FLAGS     += -Werror=unknown-warning-option
 576KBUILD_CFLAGS   += $(CLANG_FLAGS)
 577KBUILD_AFLAGS   += $(CLANG_FLAGS)
 578export CLANG_FLAGS
 579endif
 580
 581# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
 582# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
 583# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
 584# and from include/config/auto.conf.cmd to detect the compiler upgrade.
 585CC_VERSION_TEXT = $(shell $(CC) --version 2>/dev/null | head -n 1)
 586
 587ifdef config-build
 588# ===========================================================================
 589# *config targets only - make sure prerequisites are updated, and descend
 590# in scripts/kconfig to make the *config target
 591
 592# Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
 593# KBUILD_DEFCONFIG may point out an alternative default configuration
 594# used for 'make defconfig'
 595include arch/$(SRCARCH)/Makefile
 596export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
 597
 598config: outputmakefile scripts_basic FORCE
 599        $(Q)$(MAKE) $(build)=scripts/kconfig $@
 600
 601%config: outputmakefile scripts_basic FORCE
 602        $(Q)$(MAKE) $(build)=scripts/kconfig $@
 603
 604else #!config-build
 605# ===========================================================================
 606# Build targets only - this includes vmlinux, arch specific targets, clean
 607# targets and others. In general all targets except *config targets.
 608
 609# If building an external module we do not care about the all: rule
 610# but instead __all depend on modules
 611PHONY += all
 612ifeq ($(KBUILD_EXTMOD),)
 613__all: all
 614else
 615__all: modules
 616endif
 617
 618# Decide whether to build built-in, modular, or both.
 619# Normally, just do built-in.
 620
 621KBUILD_MODULES :=
 622KBUILD_BUILTIN := 1
 623
 624# If we have only "make modules", don't compile built-in objects.
 625ifeq ($(MAKECMDGOALS),modules)
 626  KBUILD_BUILTIN :=
 627endif
 628
 629# If we have "make <whatever> modules", compile modules
 630# in addition to whatever we do anyway.
 631# Just "make" or "make all" shall build modules as well
 632
 633ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
 634  KBUILD_MODULES := 1
 635endif
 636
 637ifeq ($(MAKECMDGOALS),)
 638  KBUILD_MODULES := 1
 639endif
 640
 641export KBUILD_MODULES KBUILD_BUILTIN
 642
 643ifdef need-config
 644include include/config/auto.conf
 645endif
 646
 647ifeq ($(KBUILD_EXTMOD),)
 648# Objects we will link into vmlinux / subdirs we need to visit
 649core-y          := init/ usr/
 650drivers-y       := drivers/ sound/
 651drivers-$(CONFIG_SAMPLES) += samples/
 652drivers-y       += net/ virt/
 653libs-y          := lib/
 654endif # KBUILD_EXTMOD
 655
 656# The all: target is the default when no target is given on the
 657# command line.
 658# This allow a user to issue only 'make' to build a kernel including modules
 659# Defaults to vmlinux, but the arch makefile usually adds further targets
 660all: vmlinux
 661
 662CFLAGS_GCOV     := -fprofile-arcs -ftest-coverage \
 663        $(call cc-option,-fno-tree-loop-im) \
 664        $(call cc-disable-warning,maybe-uninitialized,)
 665export CFLAGS_GCOV
 666
 667# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
 668ifdef CONFIG_FUNCTION_TRACER
 669  CC_FLAGS_FTRACE := -pg
 670endif
 671
 672RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
 673RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
 674RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
 675RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
 676RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
 677RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
 678export RETPOLINE_CFLAGS
 679export RETPOLINE_VDSO_CFLAGS
 680
 681include arch/$(SRCARCH)/Makefile
 682
 683ifdef need-config
 684ifdef may-sync-config
 685# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
 686# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
 687# because some architectures define CROSS_COMPILE there.
 688include include/config/auto.conf.cmd
 689
 690$(KCONFIG_CONFIG):
 691        @echo >&2 '***'
 692        @echo >&2 '*** Configuration file "$@" not found!'
 693        @echo >&2 '***'
 694        @echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
 695        @echo >&2 '*** "make menuconfig" or "make xconfig").'
 696        @echo >&2 '***'
 697        @/bin/false
 698
 699# The actual configuration files used during the build are stored in
 700# include/generated/ and include/config/. Update them if .config is newer than
 701# include/config/auto.conf (which mirrors .config).
 702#
 703# This exploits the 'multi-target pattern rule' trick.
 704# The syncconfig should be executed only once to make all the targets.
 705# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
 706quiet_cmd_syncconfig = SYNC    $@
 707      cmd_syncconfig = $(MAKE) -f $(srctree)/Makefile syncconfig
 708
 709%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h: $(KCONFIG_CONFIG)
 710        +$(call cmd,syncconfig)
 711else # !may-sync-config
 712# External modules and some install targets need include/generated/autoconf.h
 713# and include/config/auto.conf but do not care if they are up-to-date.
 714# Use auto.conf to trigger the test
 715PHONY += include/config/auto.conf
 716
 717include/config/auto.conf:
 718        $(Q)test -e include/generated/autoconf.h -a -e $@ || (          \
 719        echo >&2;                                                       \
 720        echo >&2 "  ERROR: Kernel configuration is invalid.";           \
 721        echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
 722        echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";      \
 723        echo >&2 ;                                                      \
 724        /bin/false)
 725
 726endif # may-sync-config
 727endif # need-config
 728
 729KBUILD_CFLAGS   += $(call cc-option,-fno-delete-null-pointer-checks,)
 730KBUILD_CFLAGS   += $(call cc-disable-warning,frame-address,)
 731KBUILD_CFLAGS   += $(call cc-disable-warning, format-truncation)
 732KBUILD_CFLAGS   += $(call cc-disable-warning, format-overflow)
 733KBUILD_CFLAGS   += $(call cc-disable-warning, address-of-packed-member)
 734
 735ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
 736KBUILD_CFLAGS += -O2
 737else ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3
 738KBUILD_CFLAGS += -O3
 739else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
 740KBUILD_CFLAGS += -Os
 741endif
 742
 743# Tell gcc to never replace conditional load with a non-conditional one
 744KBUILD_CFLAGS   += $(call cc-option,--param=allow-store-data-races=0)
 745KBUILD_CFLAGS   += $(call cc-option,-fno-allow-store-data-races)
 746
 747ifdef CONFIG_READABLE_ASM
 748# Disable optimizations that make assembler listings hard to read.
 749# reorder blocks reorders the control in the function
 750# ipa clone creates specialized cloned functions
 751# partial inlining inlines only parts of functions
 752KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
 753                 $(call cc-option,-fno-ipa-cp-clone,) \
 754                 $(call cc-option,-fno-partial-inlining)
 755endif
 756
 757ifneq ($(CONFIG_FRAME_WARN),0)
 758KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
 759endif
 760
 761stackp-flags-y                                    := -fno-stack-protector
 762stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
 763stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
 764
 765KBUILD_CFLAGS += $(stackp-flags-y)
 766
 767ifdef CONFIG_CC_IS_CLANG
 768KBUILD_CPPFLAGS += -Qunused-arguments
 769KBUILD_CFLAGS += -Wno-format-invalid-specifier
 770KBUILD_CFLAGS += -Wno-gnu
 771# CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
 772# source of a reference will be _MergedGlobals and not on of the whitelisted names.
 773# See modpost pattern 2
 774KBUILD_CFLAGS += -mno-global-merge
 775else
 776
 777# These warnings generated too much noise in a regular build.
 778# Use make W=1 to enable them (see scripts/Makefile.extrawarn)
 779KBUILD_CFLAGS += -Wno-unused-but-set-variable
 780
 781# Warn about unmarked fall-throughs in switch statement.
 782# Disabled for clang while comment to attribute conversion happens and
 783# https://github.com/ClangBuiltLinux/linux/issues/636 is discussed.
 784KBUILD_CFLAGS += $(call cc-option,-Wimplicit-fallthrough,)
 785endif
 786
 787KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
 788ifdef CONFIG_FRAME_POINTER
 789KBUILD_CFLAGS   += -fno-omit-frame-pointer -fno-optimize-sibling-calls
 790else
 791# Some targets (ARM with Thumb2, for example), can't be built with frame
 792# pointers.  For those, we don't have FUNCTION_TRACER automatically
 793# select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
 794# incompatible with -fomit-frame-pointer with current GCC, so we don't use
 795# -fomit-frame-pointer with FUNCTION_TRACER.
 796ifndef CONFIG_FUNCTION_TRACER
 797KBUILD_CFLAGS   += -fomit-frame-pointer
 798endif
 799endif
 800
 801# Initialize all stack variables with a 0xAA pattern.
 802ifdef CONFIG_INIT_STACK_ALL_PATTERN
 803KBUILD_CFLAGS   += -ftrivial-auto-var-init=pattern
 804endif
 805
 806# Initialize all stack variables with a zero value.
 807ifdef CONFIG_INIT_STACK_ALL_ZERO
 808# Future support for zero initialization is still being debated, see
 809# https://bugs.llvm.org/show_bug.cgi?id=45497. These flags are subject to being
 810# renamed or dropped.
 811KBUILD_CFLAGS   += -ftrivial-auto-var-init=zero
 812KBUILD_CFLAGS   += -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
 813endif
 814
 815# Workaround for GCC versions < 5.0
 816# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61801
 817ifdef CONFIG_CC_IS_GCC
 818DEBUG_CFLAGS    := $(call cc-ifversion, -lt, 0500, $(call cc-option, -fno-var-tracking-assignments))
 819endif
 820
 821ifdef CONFIG_DEBUG_INFO
 822
 823ifdef CONFIG_DEBUG_INFO_SPLIT
 824DEBUG_CFLAGS    += -gsplit-dwarf
 825else
 826DEBUG_CFLAGS    += -g
 827endif
 828
 829ifneq ($(LLVM_IAS),1)
 830KBUILD_AFLAGS   += -Wa,-gdwarf-2
 831endif
 832
 833ifdef CONFIG_DEBUG_INFO_DWARF4
 834DEBUG_CFLAGS    += -gdwarf-4
 835endif
 836
 837ifdef CONFIG_DEBUG_INFO_REDUCED
 838DEBUG_CFLAGS    += $(call cc-option, -femit-struct-debug-baseonly) \
 839                   $(call cc-option,-fno-var-tracking)
 840endif
 841
 842ifdef CONFIG_DEBUG_INFO_COMPRESSED
 843DEBUG_CFLAGS    += -gz=zlib
 844KBUILD_AFLAGS   += -gz=zlib
 845KBUILD_LDFLAGS  += --compress-debug-sections=zlib
 846endif
 847
 848endif # CONFIG_DEBUG_INFO
 849
 850KBUILD_CFLAGS += $(DEBUG_CFLAGS)
 851export DEBUG_CFLAGS
 852
 853ifdef CONFIG_FUNCTION_TRACER
 854ifdef CONFIG_FTRACE_MCOUNT_RECORD
 855  # gcc 5 supports generating the mcount tables directly
 856  ifeq ($(call cc-option-yn,-mrecord-mcount),y)
 857    CC_FLAGS_FTRACE     += -mrecord-mcount
 858    export CC_USING_RECORD_MCOUNT := 1
 859  endif
 860  ifdef CONFIG_HAVE_NOP_MCOUNT
 861    ifeq ($(call cc-option-yn, -mnop-mcount),y)
 862      CC_FLAGS_FTRACE   += -mnop-mcount
 863      CC_FLAGS_USING    += -DCC_USING_NOP_MCOUNT
 864    endif
 865  endif
 866endif
 867ifdef CONFIG_HAVE_FENTRY
 868  ifeq ($(call cc-option-yn, -mfentry),y)
 869    CC_FLAGS_FTRACE     += -mfentry
 870    CC_FLAGS_USING      += -DCC_USING_FENTRY
 871  endif
 872endif
 873export CC_FLAGS_FTRACE
 874KBUILD_CFLAGS   += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
 875KBUILD_AFLAGS   += $(CC_FLAGS_USING)
 876ifdef CONFIG_DYNAMIC_FTRACE
 877        ifdef CONFIG_HAVE_C_RECORDMCOUNT
 878                BUILD_C_RECORDMCOUNT := y
 879                export BUILD_C_RECORDMCOUNT
 880        endif
 881endif
 882endif
 883
 884# We trigger additional mismatches with less inlining
 885ifdef CONFIG_DEBUG_SECTION_MISMATCH
 886KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
 887endif
 888
 889ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
 890KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
 891LDFLAGS_vmlinux += --gc-sections
 892endif
 893
 894ifdef CONFIG_SHADOW_CALL_STACK
 895CC_FLAGS_SCS    := -fsanitize=shadow-call-stack
 896KBUILD_CFLAGS   += $(CC_FLAGS_SCS)
 897export CC_FLAGS_SCS
 898endif
 899
 900ifdef CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_32B
 901KBUILD_CFLAGS += -falign-functions=32
 902endif
 903
 904# arch Makefile may override CC so keep this after arch Makefile is included
 905NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
 906
 907# warn about C99 declaration after statement
 908KBUILD_CFLAGS += -Wdeclaration-after-statement
 909
 910# Variable Length Arrays (VLAs) should not be used anywhere in the kernel
 911KBUILD_CFLAGS += -Wvla
 912
 913# disable pointer signed / unsigned warnings in gcc 4.0
 914KBUILD_CFLAGS += -Wno-pointer-sign
 915
 916# disable stringop warnings in gcc 8+
 917KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
 918
 919# We'll want to enable this eventually, but it's not going away for 5.7 at least
 920KBUILD_CFLAGS += $(call cc-disable-warning, zero-length-bounds)
 921KBUILD_CFLAGS += $(call cc-disable-warning, array-bounds)
 922KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
 923
 924# Another good warning that we'll want to enable eventually
 925KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
 926
 927# Enabled with W=2, disabled by default as noisy
 928KBUILD_CFLAGS += $(call cc-disable-warning, maybe-uninitialized)
 929
 930# disable invalid "can't wrap" optimizations for signed / pointers
 931KBUILD_CFLAGS   += -fno-strict-overflow
 932
 933# Make sure -fstack-check isn't enabled (like gentoo apparently did)
 934KBUILD_CFLAGS  += -fno-stack-check
 935
 936# conserve stack if available
 937KBUILD_CFLAGS   += $(call cc-option,-fconserve-stack)
 938
 939# Prohibit date/time macros, which would make the build non-deterministic
 940KBUILD_CFLAGS   += -Werror=date-time
 941
 942# enforce correct pointer usage
 943KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)
 944
 945# Require designated initializers for all marked structures
 946KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)
 947
 948# change __FILE__ to the relative path from the srctree
 949KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
 950
 951# ensure -fcf-protection is disabled when using retpoline as it is
 952# incompatible with -mindirect-branch=thunk-extern
 953ifdef CONFIG_RETPOLINE
 954KBUILD_CFLAGS += $(call cc-option,-fcf-protection=none)
 955endif
 956
 957# include additional Makefiles when needed
 958include-y                       := scripts/Makefile.extrawarn
 959include-$(CONFIG_KASAN)         += scripts/Makefile.kasan
 960include-$(CONFIG_KCSAN)         += scripts/Makefile.kcsan
 961include-$(CONFIG_UBSAN)         += scripts/Makefile.ubsan
 962include-$(CONFIG_KCOV)          += scripts/Makefile.kcov
 963include-$(CONFIG_GCC_PLUGINS)   += scripts/Makefile.gcc-plugins
 964
 965include $(addprefix $(srctree)/, $(include-y))
 966
 967# scripts/Makefile.gcc-plugins is intentionally included last.
 968# Do not add $(call cc-option,...) below this line. When you build the kernel
 969# from the clean source tree, the GCC plugins do not exist at this point.
 970
 971# Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
 972KBUILD_CPPFLAGS += $(KCPPFLAGS)
 973KBUILD_AFLAGS   += $(KAFLAGS)
 974KBUILD_CFLAGS   += $(KCFLAGS)
 975
 976KBUILD_LDFLAGS_MODULE += --build-id=sha1
 977LDFLAGS_vmlinux += --build-id=sha1
 978
 979ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
 980LDFLAGS_vmlinux += $(call ld-option, -X,)
 981endif
 982
 983ifeq ($(CONFIG_RELR),y)
 984LDFLAGS_vmlinux += --pack-dyn-relocs=relr
 985endif
 986
 987# We never want expected sections to be placed heuristically by the
 988# linker. All sections should be explicitly named in the linker script.
 989ifdef CONFIG_LD_ORPHAN_WARN
 990LDFLAGS_vmlinux += --orphan-handling=warn
 991endif
 992
 993# Align the bit size of userspace programs with the kernel
 994KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
 995KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
 996
 997# make the checker run with the right architecture
 998CHECKFLAGS += --arch=$(ARCH)
 999
1000# insure the checker run with the right endianness
1001CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1002
1003# the checker needs the correct machine size
1004CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1005
1006# Default kernel image to build when no specific target is given.
1007# KBUILD_IMAGE may be overruled on the command line or
1008# set in the environment
1009# Also any assignments in arch/$(ARCH)/Makefile take precedence over
1010# this default value
1011export KBUILD_IMAGE ?= vmlinux
1012
1013#
1014# INSTALL_PATH specifies where to place the updated kernel and system map
1015# images. Default is /boot, but you can set it to other values
1016export  INSTALL_PATH ?= /boot
1017
1018#
1019# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1020# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1021# an argument if needed. Otherwise it defaults to the kernel install path
1022#
1023export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1024
1025#
1026# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1027# relocations required by build roots.  This is not defined in the
1028# makefile but the argument can be passed to make if needed.
1029#
1030
1031MODLIB  = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1032export MODLIB
1033
1034#
1035# INSTALL_MOD_STRIP, if defined, will cause modules to be
1036# stripped after they are installed.  If INSTALL_MOD_STRIP is '1', then
1037# the default option --strip-debug will be used.  Otherwise,
1038# INSTALL_MOD_STRIP value will be used as the options to the strip command.
1039
1040ifdef INSTALL_MOD_STRIP
1041ifeq ($(INSTALL_MOD_STRIP),1)
1042mod_strip_cmd = $(STRIP) --strip-debug
1043else
1044mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
1045endif # INSTALL_MOD_STRIP=1
1046else
1047mod_strip_cmd = true
1048endif # INSTALL_MOD_STRIP
1049export mod_strip_cmd
1050
1051# CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
1052# after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
1053# or CONFIG_MODULE_COMPRESS_XZ.
1054
1055mod_compress_cmd = true
1056ifdef CONFIG_MODULE_COMPRESS
1057  ifdef CONFIG_MODULE_COMPRESS_GZIP
1058    mod_compress_cmd = $(KGZIP) -n -f
1059  endif # CONFIG_MODULE_COMPRESS_GZIP
1060  ifdef CONFIG_MODULE_COMPRESS_XZ
1061    mod_compress_cmd = $(XZ) -f
1062  endif # CONFIG_MODULE_COMPRESS_XZ
1063endif # CONFIG_MODULE_COMPRESS
1064export mod_compress_cmd
1065
1066ifdef CONFIG_MODULE_SIG_ALL
1067$(eval $(call config_filename,MODULE_SIG_KEY))
1068
1069mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
1070else
1071mod_sign_cmd = true
1072endif
1073export mod_sign_cmd
1074
1075HOST_LIBELF_LIBS = $(shell pkg-config libelf --libs 2>/dev/null || echo -lelf)
1076
1077has_libelf = $(call try-run,\
1078               echo "int main() {}" | $(HOSTCC) -xc -o /dev/null $(HOST_LIBELF_LIBS) -,1,0)
1079
1080ifdef CONFIG_STACK_VALIDATION
1081  ifeq ($(has_libelf),1)
1082    objtool_target := tools/objtool FORCE
1083  else
1084    SKIP_STACK_VALIDATION := 1
1085    export SKIP_STACK_VALIDATION
1086  endif
1087endif
1088
1089ifdef CONFIG_BPF
1090ifdef CONFIG_DEBUG_INFO_BTF
1091  ifeq ($(has_libelf),1)
1092    resolve_btfids_target := tools/bpf/resolve_btfids FORCE
1093  else
1094    ERROR_RESOLVE_BTFIDS := 1
1095  endif
1096endif # CONFIG_DEBUG_INFO_BTF
1097endif # CONFIG_BPF
1098
1099PHONY += prepare0
1100
1101export MODORDER := $(extmod-prefix)modules.order
1102export MODULES_NSDEPS := $(extmod-prefix)modules.nsdeps
1103
1104ifeq ($(KBUILD_EXTMOD),)
1105core-y          += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
1106
1107vmlinux-dirs    := $(patsubst %/,%,$(filter %/, \
1108                     $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
1109                     $(libs-y) $(libs-m)))
1110
1111vmlinux-alldirs := $(sort $(vmlinux-dirs) Documentation \
1112                     $(patsubst %/,%,$(filter %/, $(core-) \
1113                        $(drivers-) $(libs-))))
1114
1115subdir-modorder := $(addsuffix modules.order,$(filter %/, \
1116                        $(core-y) $(core-m) $(libs-y) $(libs-m) \
1117                        $(drivers-y) $(drivers-m)))
1118
1119build-dirs      := $(vmlinux-dirs)
1120clean-dirs      := $(vmlinux-alldirs)
1121
1122# Externally visible symbols (used by link-vmlinux.sh)
1123KBUILD_VMLINUX_OBJS := $(head-y) $(patsubst %/,%/built-in.a, $(core-y))
1124KBUILD_VMLINUX_OBJS += $(addsuffix built-in.a, $(filter %/, $(libs-y)))
1125ifdef CONFIG_MODULES
1126KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1127KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1128else
1129KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1130endif
1131KBUILD_VMLINUX_OBJS += $(patsubst %/,%/built-in.a, $(drivers-y))
1132
1133export KBUILD_VMLINUX_OBJS KBUILD_VMLINUX_LIBS
1134export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1135# used by scripts/Makefile.package
1136export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) LICENSES arch include scripts tools)
1137
1138vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
1139
1140# Recurse until adjust_autoksyms.sh is satisfied
1141PHONY += autoksyms_recursive
1142ifdef CONFIG_TRIM_UNUSED_KSYMS
1143# For the kernel to actually contain only the needed exported symbols,
1144# we have to build modules as well to determine what those symbols are.
1145# (this can be evaluated only once include/config/auto.conf has been included)
1146KBUILD_MODULES := 1
1147
1148autoksyms_recursive: descend modules.order
1149        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1150          "$(MAKE) -f $(srctree)/Makefile vmlinux"
1151endif
1152
1153autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1154
1155quiet_cmd_autoksyms_h = GEN     $@
1156      cmd_autoksyms_h = mkdir -p $(dir $@); \
1157                        $(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@
1158
1159$(autoksyms_h):
1160        $(call cmd,autoksyms_h)
1161
1162ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1163
1164# Final link of vmlinux with optional arch pass after final link
1165cmd_link-vmlinux =                                                 \
1166        $(CONFIG_SHELL) $< "$(LD)" "$(KBUILD_LDFLAGS)" "$(LDFLAGS_vmlinux)";    \
1167        $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1168
1169vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1170        +$(call if_changed,link-vmlinux)
1171
1172targets := vmlinux
1173
1174# The actual objects are generated when descending,
1175# make sure no implicit rule kicks in
1176$(sort $(vmlinux-deps) $(subdir-modorder)): descend ;
1177
1178filechk_kernel.release = \
1179        echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1180
1181# Store (new) KERNELRELEASE string in include/config/kernel.release
1182include/config/kernel.release: FORCE
1183        $(call filechk,kernel.release)
1184
1185# Additional helpers built in scripts/
1186# Carefully list dependencies so we do not try to build scripts twice
1187# in parallel
1188PHONY += scripts
1189scripts: scripts_basic scripts_dtc
1190        $(Q)$(MAKE) $(build)=$(@)
1191
1192# Things we need to do before we recursively start building the kernel
1193# or the modules are listed in "prepare".
1194# A multi level approach is used. prepareN is processed before prepareN-1.
1195# archprepare is used in arch Makefiles and when processed asm symlink,
1196# version.h and scripts_basic is processed / created.
1197
1198PHONY += prepare archprepare
1199
1200archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1201        asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h \
1202        include/generated/autoconf.h
1203
1204prepare0: archprepare
1205        $(Q)$(MAKE) $(build)=scripts/mod
1206        $(Q)$(MAKE) $(build)=.
1207
1208# All the preparing..
1209prepare: prepare0 prepare-objtool prepare-resolve_btfids
1210
1211# Support for using generic headers in asm-generic
1212asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1213
1214PHONY += asm-generic uapi-asm-generic
1215asm-generic: uapi-asm-generic
1216        $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1217        generic=include/asm-generic
1218uapi-asm-generic:
1219        $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1220        generic=include/uapi/asm-generic
1221
1222PHONY += prepare-objtool prepare-resolve_btfids
1223prepare-objtool: $(objtool_target)
1224ifeq ($(SKIP_STACK_VALIDATION),1)
1225ifdef CONFIG_UNWINDER_ORC
1226        @echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1227        @false
1228else
1229        @echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1230endif
1231endif
1232
1233prepare-resolve_btfids: $(resolve_btfids_target)
1234ifeq ($(ERROR_RESOLVE_BTFIDS),1)
1235        @echo "error: Cannot resolve BTF IDs for CONFIG_DEBUG_INFO_BTF, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1236        @false
1237endif
1238# Generate some files
1239# ---------------------------------------------------------------------------
1240
1241# KERNELRELEASE can change from a few different places, meaning version.h
1242# needs to be updated, so this check is forced on all builds
1243
1244uts_len := 64
1245define filechk_utsrelease.h
1246        if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1247          echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1248          exit 1;                                                         \
1249        fi;                                                               \
1250        echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1251endef
1252
1253define filechk_version.h
1254        echo \#define LINUX_VERSION_CODE $(shell                         \
1255        expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1256        echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))'
1257endef
1258
1259$(version_h): FORCE
1260        $(call filechk,version.h)
1261        $(Q)rm -f $(old_version_h)
1262
1263include/generated/utsrelease.h: include/config/kernel.release FORCE
1264        $(call filechk,utsrelease.h)
1265
1266PHONY += headerdep
1267headerdep:
1268        $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1269        $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1270
1271# ---------------------------------------------------------------------------
1272# Kernel headers
1273
1274#Default location for installed headers
1275export INSTALL_HDR_PATH = $(objtree)/usr
1276
1277quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1278      cmd_headers_install = \
1279        mkdir -p $(INSTALL_HDR_PATH); \
1280        rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1281        usr/include $(INSTALL_HDR_PATH)
1282
1283PHONY += headers_install
1284headers_install: headers
1285        $(call cmd,headers_install)
1286
1287PHONY += archheaders archscripts
1288
1289hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1290
1291PHONY += headers
1292headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1293        $(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1294          $(error Headers not exportable for the $(SRCARCH) architecture))
1295        $(Q)$(MAKE) $(hdr-inst)=include/uapi
1296        $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1297
1298# Deprecated. It is no-op now.
1299PHONY += headers_check
1300headers_check:
1301        @:
1302
1303ifdef CONFIG_HEADERS_INSTALL
1304prepare: headers
1305endif
1306
1307PHONY += scripts_unifdef
1308scripts_unifdef: scripts_basic
1309        $(Q)$(MAKE) $(build)=scripts scripts/unifdef
1310
1311# ---------------------------------------------------------------------------
1312# Kernel selftest
1313
1314PHONY += kselftest
1315kselftest:
1316        $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1317
1318kselftest-%: FORCE
1319        $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1320
1321PHONY += kselftest-merge
1322kselftest-merge:
1323        $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1324        $(Q)find $(srctree)/tools/testing/selftests -name config | \
1325                xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1326        $(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1327
1328# ---------------------------------------------------------------------------
1329# Devicetree files
1330
1331ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1332dtstree := arch/$(SRCARCH)/boot/dts
1333endif
1334
1335ifneq ($(dtstree),)
1336
1337%.dtb: include/config/kernel.release scripts_dtc
1338        $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1339
1340PHONY += dtbs dtbs_install dtbs_check
1341dtbs: include/config/kernel.release scripts_dtc
1342        $(Q)$(MAKE) $(build)=$(dtstree)
1343
1344ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1345export CHECK_DTBS=y
1346dtbs: dt_binding_check
1347endif
1348
1349dtbs_check: dtbs
1350
1351dtbs_install:
1352        $(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1353
1354ifdef CONFIG_OF_EARLY_FLATTREE
1355all: dtbs
1356endif
1357
1358endif
1359
1360PHONY += scripts_dtc
1361scripts_dtc: scripts_basic
1362        $(Q)$(MAKE) $(build)=scripts/dtc
1363
1364ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1365export CHECK_DT_BINDING=y
1366endif
1367
1368PHONY += dt_binding_check
1369dt_binding_check: scripts_dtc
1370        $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1371
1372# ---------------------------------------------------------------------------
1373# Modules
1374
1375ifdef CONFIG_MODULES
1376
1377# By default, build modules as well
1378
1379all: modules
1380
1381# When we're building modules with modversions, we need to consider
1382# the built-in objects during the descend as well, in order to
1383# make sure the checksums are up to date before we record them.
1384ifdef CONFIG_MODVERSIONS
1385  KBUILD_BUILTIN := 1
1386endif
1387
1388# Build modules
1389#
1390# A module can be listed more than once in obj-m resulting in
1391# duplicate lines in modules.order files.  Those are removed
1392# using awk while concatenating to the final file.
1393
1394PHONY += modules
1395modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_check modules_prepare
1396        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1397
1398PHONY += modules_check
1399modules_check: modules.order
1400        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1401
1402cmd_modules_order = $(AWK) '!x[$$0]++' $(real-prereqs) > $@
1403
1404modules.order: $(subdir-modorder) FORCE
1405        $(call if_changed,modules_order)
1406
1407targets += modules.order
1408
1409# Target to prepare building external modules
1410PHONY += modules_prepare
1411modules_prepare: prepare
1412        $(Q)$(MAKE) $(build)=scripts scripts/module.lds
1413
1414# Target to install modules
1415PHONY += modules_install
1416modules_install: _modinst_ _modinst_post
1417
1418PHONY += _modinst_
1419_modinst_:
1420        @rm -rf $(MODLIB)/kernel
1421        @rm -f $(MODLIB)/source
1422        @mkdir -p $(MODLIB)/kernel
1423        @ln -s $(abspath $(srctree)) $(MODLIB)/source
1424        @if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
1425                rm -f $(MODLIB)/build ; \
1426                ln -s $(CURDIR) $(MODLIB)/build ; \
1427        fi
1428        @sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order
1429        @cp -f modules.builtin $(MODLIB)/
1430        @cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
1431        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1432
1433# This depmod is only for convenience to give the initial
1434# boot a modules.dep even before / is mounted read-write.  However the
1435# boot script depmod is the master version.
1436PHONY += _modinst_post
1437_modinst_post: _modinst_
1438        $(call cmd,depmod)
1439
1440ifeq ($(CONFIG_MODULE_SIG), y)
1441PHONY += modules_sign
1442modules_sign:
1443        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1444endif
1445
1446else # CONFIG_MODULES
1447
1448# Modules not configured
1449# ---------------------------------------------------------------------------
1450
1451PHONY += modules modules_install
1452modules modules_install:
1453        @echo >&2
1454        @echo >&2 "The present kernel configuration has modules disabled."
1455        @echo >&2 "Type 'make config' and enable loadable module support."
1456        @echo >&2 "Then build a kernel with module support enabled."
1457        @echo >&2
1458        @exit 1
1459
1460endif # CONFIG_MODULES
1461
1462###
1463# Cleaning is done on three levels.
1464# make clean     Delete most generated files
1465#                Leave enough to build external modules
1466# make mrproper  Delete the current configuration, and all generated files
1467# make distclean Remove editor backup files, patch leftover files and the like
1468
1469# Directories & files removed with 'make clean'
1470CLEAN_FILES += include/ksym vmlinux.symvers \
1471               modules.builtin modules.builtin.modinfo modules.nsdeps \
1472               compile_commands.json
1473
1474# Directories & files removed with 'make mrproper'
1475MRPROPER_FILES += include/config include/generated          \
1476                  arch/$(SRCARCH)/include/generated .tmp_objdiff \
1477                  debian snap tar-install \
1478                  .config .config.old .version \
1479                  Module.symvers \
1480                  signing_key.pem signing_key.priv signing_key.x509     \
1481                  x509.genkey extra_certificates signing_key.x509.keyid \
1482                  signing_key.x509.signer vmlinux-gdb.py \
1483                  *.spec
1484
1485# Directories & files removed with 'make distclean'
1486DISTCLEAN_FILES += tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS
1487
1488# clean - Delete most, but leave enough to build external modules
1489#
1490clean: rm-files := $(CLEAN_FILES)
1491
1492PHONY += archclean vmlinuxclean
1493
1494vmlinuxclean:
1495        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1496        $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1497
1498clean: archclean vmlinuxclean
1499
1500# mrproper - Delete all generated files, including .config
1501#
1502mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1503mrproper-dirs      := $(addprefix _mrproper_,scripts)
1504
1505PHONY += $(mrproper-dirs) mrproper
1506$(mrproper-dirs):
1507        $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1508
1509mrproper: clean $(mrproper-dirs)
1510        $(call cmd,rmfiles)
1511
1512# distclean
1513#
1514distclean: rm-files := $(wildcard $(DISTCLEAN_FILES))
1515
1516PHONY += distclean
1517
1518distclean: mrproper
1519        $(call cmd,rmfiles)
1520        @find $(srctree) $(RCS_FIND_IGNORE) \
1521                \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1522                -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1523                -o -name 'core' \) \
1524                -type f -print | xargs rm -f
1525
1526
1527# Packaging of the kernel to various formats
1528# ---------------------------------------------------------------------------
1529
1530%src-pkg: FORCE
1531        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1532%pkg: include/config/kernel.release FORCE
1533        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1534
1535# Brief documentation of the typical targets used
1536# ---------------------------------------------------------------------------
1537
1538boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1539boards := $(sort $(notdir $(boards)))
1540board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1541board-dirs := $(sort $(notdir $(board-dirs:/=)))
1542
1543PHONY += help
1544help:
1545        @echo  'Cleaning targets:'
1546        @echo  '  clean           - Remove most generated files but keep the config and'
1547        @echo  '                    enough build support to build external modules'
1548        @echo  '  mrproper        - Remove all generated files + config + various backup files'
1549        @echo  '  distclean       - mrproper + remove editor backup and patch files'
1550        @echo  ''
1551        @echo  'Configuration targets:'
1552        @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1553        @echo  ''
1554        @echo  'Other generic targets:'
1555        @echo  '  all             - Build all targets marked with [*]'
1556        @echo  '* vmlinux         - Build the bare kernel'
1557        @echo  '* modules         - Build all modules'
1558        @echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1559        @echo  '  dir/            - Build all files in dir and below'
1560        @echo  '  dir/file.[ois]  - Build specified target only'
1561        @echo  '  dir/file.ll     - Build the LLVM assembly file'
1562        @echo  '                    (requires compiler support for LLVM assembly generation)'
1563        @echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1564        @echo  '                    (requires a recent binutils and recent build (System.map))'
1565        @echo  '  dir/file.ko     - Build module including final link'
1566        @echo  '  modules_prepare - Set up for building external modules'
1567        @echo  '  tags/TAGS       - Generate tags file for editors'
1568        @echo  '  cscope          - Generate cscope index'
1569        @echo  '  gtags           - Generate GNU GLOBAL index'
1570        @echo  '  kernelrelease   - Output the release version string (use with make -s)'
1571        @echo  '  kernelversion   - Output the version stored in Makefile (use with make -s)'
1572        @echo  '  image_name      - Output the image name (use with make -s)'
1573        @echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1574         echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1575         echo  ''
1576        @echo  'Static analysers:'
1577        @echo  '  checkstack      - Generate a list of stack hogs'
1578        @echo  '  versioncheck    - Sanity check on version.h usage'
1579        @echo  '  includecheck    - Check for duplicate included header files'
1580        @echo  '  export_report   - List the usages of all exported symbols'
1581        @echo  '  headerdep       - Detect inclusion cycles in headers'
1582        @echo  '  coccicheck      - Check with Coccinelle'
1583        @echo  '  clang-analyzer  - Check with clang static analyzer'
1584        @echo  '  clang-tidy      - Check with clang-tidy'
1585        @echo  ''
1586        @echo  'Tools:'
1587        @echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1588        @echo  ''
1589        @echo  'Kernel selftest:'
1590        @echo  '  kselftest         - Build and run kernel selftest'
1591        @echo  '                      Build, install, and boot kernel before'
1592        @echo  '                      running kselftest on it'
1593        @echo  '                      Run as root for full coverage'
1594        @echo  '  kselftest-all     - Build kernel selftest'
1595        @echo  '  kselftest-install - Build and install kernel selftest'
1596        @echo  '  kselftest-clean   - Remove all generated kselftest files'
1597        @echo  '  kselftest-merge   - Merge all the config dependencies of'
1598        @echo  '                      kselftest to existing .config.'
1599        @echo  ''
1600        @$(if $(dtstree), \
1601                echo 'Devicetree:'; \
1602                echo '* dtbs             - Build device tree blobs for enabled boards'; \
1603                echo '  dtbs_install     - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1604                echo '  dt_binding_check - Validate device tree binding documents'; \
1605                echo '  dtbs_check       - Validate device tree source files';\
1606                echo '')
1607
1608        @echo 'Userspace tools targets:'
1609        @echo '  use "make tools/help"'
1610        @echo '  or  "cd tools; make help"'
1611        @echo  ''
1612        @echo  'Kernel packaging:'
1613        @$(MAKE) -f $(srctree)/scripts/Makefile.package help
1614        @echo  ''
1615        @echo  'Documentation targets:'
1616        @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1617        @echo  ''
1618        @echo  'Architecture specific targets ($(SRCARCH)):'
1619        @$(if $(archhelp),$(archhelp),\
1620                echo '  No architecture specific help defined for $(SRCARCH)')
1621        @echo  ''
1622        @$(if $(boards), \
1623                $(foreach b, $(boards), \
1624                printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1625                echo '')
1626        @$(if $(board-dirs), \
1627                $(foreach b, $(board-dirs), \
1628                printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1629                printf "  %-16s - Show all of the above\\n" help-boards; \
1630                echo '')
1631
1632        @echo  '  make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1633        @echo  '  make V=2   [targets] 2 => give reason for rebuild of target'
1634        @echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1635        @echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1636        @echo  '                       (sparse by default)'
1637        @echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1638        @echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1639        @echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
1640        @echo  '                1: warnings which may be relevant and do not occur too often'
1641        @echo  '                2: warnings which occur quite often but may still be relevant'
1642        @echo  '                3: more obscure warnings, can most likely be ignored'
1643        @echo  '                Multiple levels can be combined with W=12 or W=123'
1644        @echo  ''
1645        @echo  'Execute "make" or "make all" to build all targets marked with [*] '
1646        @echo  'For further info see the ./README file'
1647
1648
1649help-board-dirs := $(addprefix help-,$(board-dirs))
1650
1651help-boards: $(help-board-dirs)
1652
1653boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1654
1655$(help-board-dirs): help-%:
1656        @echo  'Architecture specific targets ($(SRCARCH) $*):'
1657        @$(if $(boards-per-dir), \
1658                $(foreach b, $(boards-per-dir), \
1659                printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1660                echo '')
1661
1662
1663# Documentation targets
1664# ---------------------------------------------------------------------------
1665DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1666               linkcheckdocs dochelp refcheckdocs
1667PHONY += $(DOC_TARGETS)
1668$(DOC_TARGETS):
1669        $(Q)$(MAKE) $(build)=Documentation $@
1670
1671# Misc
1672# ---------------------------------------------------------------------------
1673
1674PHONY += scripts_gdb
1675scripts_gdb: prepare0
1676        $(Q)$(MAKE) $(build)=scripts/gdb
1677        $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1678
1679ifdef CONFIG_GDB_SCRIPTS
1680all: scripts_gdb
1681endif
1682
1683else # KBUILD_EXTMOD
1684
1685###
1686# External module support.
1687# When building external modules the kernel used as basis is considered
1688# read-only, and no consistency checks are made and the make
1689# system is not used on the basis kernel. If updates are required
1690# in the basis kernel ordinary make commands (without M=...) must
1691# be used.
1692#
1693# The following are the only valid targets when building external
1694# modules.
1695# make M=dir clean     Delete all automatically generated files
1696# make M=dir modules   Make all modules in specified dir
1697# make M=dir           Same as 'make M=dir modules'
1698# make M=dir modules_install
1699#                      Install the modules built in the module directory
1700#                      Assumes install directory is already created
1701
1702# We are always building only modules.
1703KBUILD_BUILTIN :=
1704KBUILD_MODULES := 1
1705
1706build-dirs := $(KBUILD_EXTMOD)
1707PHONY += modules
1708modules: $(MODORDER)
1709        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1710
1711$(MODORDER): descend
1712        @:
1713
1714PHONY += modules_install
1715modules_install: _emodinst_ _emodinst_post
1716
1717install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1718PHONY += _emodinst_
1719_emodinst_:
1720        $(Q)mkdir -p $(MODLIB)/$(install-dir)
1721        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1722
1723PHONY += _emodinst_post
1724_emodinst_post: _emodinst_
1725        $(call cmd,depmod)
1726
1727compile_commands.json: $(extmod-prefix)compile_commands.json
1728PHONY += compile_commands.json
1729
1730clean-dirs := $(KBUILD_EXTMOD)
1731clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1732        $(KBUILD_EXTMOD)/compile_commands.json
1733
1734PHONY += help
1735help:
1736        @echo  '  Building external modules.'
1737        @echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1738        @echo  ''
1739        @echo  '  modules         - default target, build the module(s)'
1740        @echo  '  modules_install - install the module'
1741        @echo  '  clean           - remove generated files in module directory only'
1742        @echo  ''
1743
1744# no-op for external module builds
1745PHONY += prepare modules_prepare
1746
1747endif # KBUILD_EXTMOD
1748
1749# Single targets
1750# ---------------------------------------------------------------------------
1751# To build individual files in subdirectories, you can do like this:
1752#
1753#   make foo/bar/baz.s
1754#
1755# The supported suffixes for single-target are listed in 'single-targets'
1756#
1757# To build only under specific subdirectories, you can do like this:
1758#
1759#   make foo/bar/baz/
1760
1761ifdef single-build
1762
1763# .ko is special because modpost is needed
1764single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1765single-no-ko := $(sort $(patsubst %.ko,%.mod, $(MAKECMDGOALS)))
1766
1767$(single-ko): single_modpost
1768        @:
1769$(single-no-ko): descend
1770        @:
1771
1772ifeq ($(KBUILD_EXTMOD),)
1773# For the single build of in-tree modules, use a temporary file to avoid
1774# the situation of modules_install installing an invalid modules.order.
1775MODORDER := .modules.tmp
1776endif
1777
1778PHONY += single_modpost
1779single_modpost: $(single-no-ko) modules_prepare
1780        $(Q){ $(foreach m, $(single-ko), echo $(extmod-prefix)$m;) } > $(MODORDER)
1781        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1782
1783KBUILD_MODULES := 1
1784
1785export KBUILD_SINGLE_TARGETS := $(addprefix $(extmod-prefix), $(single-no-ko))
1786
1787# trim unrelated directories
1788build-dirs := $(foreach d, $(build-dirs), \
1789                        $(if $(filter $(d)/%, $(KBUILD_SINGLE_TARGETS)), $(d)))
1790
1791endif
1792
1793ifndef CONFIG_MODULES
1794KBUILD_MODULES :=
1795endif
1796
1797# Handle descending into subdirectories listed in $(build-dirs)
1798# Preset locale variables to speed up the build process. Limit locale
1799# tweaks to this spot to avoid wrong language settings when running
1800# make menuconfig etc.
1801# Error messages still appears in the original language
1802PHONY += descend $(build-dirs)
1803descend: $(build-dirs)
1804$(build-dirs): prepare
1805        $(Q)$(MAKE) $(build)=$@ \
1806        single-build=$(if $(filter-out $@/, $(filter $@/%, $(KBUILD_SINGLE_TARGETS))),1) \
1807        need-builtin=1 need-modorder=1
1808
1809clean-dirs := $(addprefix _clean_, $(clean-dirs))
1810PHONY += $(clean-dirs) clean
1811$(clean-dirs):
1812        $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1813
1814clean: $(clean-dirs)
1815        $(call cmd,rmfiles)
1816        @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1817                \( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1818                -o -name '*.ko.*' \
1819                -o -name '*.dtb' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1820                -o -name '*.dwo' -o -name '*.lst' \
1821                -o -name '*.su' -o -name '*.mod' \
1822                -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1823                -o -name '*.lex.c' -o -name '*.tab.[ch]' \
1824                -o -name '*.asn1.[ch]' \
1825                -o -name '*.symtypes' -o -name 'modules.order' \
1826                -o -name '.tmp_*.o.*' \
1827                -o -name '*.c.[012]*.*' \
1828                -o -name '*.ll' \
1829                -o -name '*.gcno' \) -type f -print | xargs rm -f
1830
1831# Generate tags for editors
1832# ---------------------------------------------------------------------------
1833quiet_cmd_tags = GEN     $@
1834      cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1835
1836tags TAGS cscope gtags: FORCE
1837        $(call cmd,tags)
1838
1839# Script to generate missing namespace dependencies
1840# ---------------------------------------------------------------------------
1841
1842PHONY += nsdeps
1843nsdeps: export KBUILD_NSDEPS=1
1844nsdeps: modules
1845        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1846
1847# Clang Tooling
1848# ---------------------------------------------------------------------------
1849
1850quiet_cmd_gen_compile_commands = GEN     $@
1851      cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
1852
1853$(extmod-prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
1854        $(if $(KBUILD_EXTMOD),,$(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)) \
1855        $(if $(CONFIG_MODULES), $(MODORDER)) FORCE
1856        $(call if_changed,gen_compile_commands)
1857
1858targets += $(extmod-prefix)compile_commands.json
1859
1860PHONY += clang-tidy clang-analyzer
1861
1862ifdef CONFIG_CC_IS_CLANG
1863quiet_cmd_clang_tools = CHECK   $<
1864      cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
1865
1866clang-tidy clang-analyzer: $(extmod-prefix)compile_commands.json
1867        $(call cmd,clang_tools)
1868else
1869clang-tidy clang-analyzer:
1870        @echo "$@ requires CC=clang" >&2
1871        @false
1872endif
1873
1874# Scripts to check various things for consistency
1875# ---------------------------------------------------------------------------
1876
1877PHONY += includecheck versioncheck coccicheck export_report
1878
1879includecheck:
1880        find $(srctree)/* $(RCS_FIND_IGNORE) \
1881                -name '*.[hcS]' -type f -print | sort \
1882                | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1883
1884versioncheck:
1885        find $(srctree)/* $(RCS_FIND_IGNORE) \
1886                -name '*.[hcS]' -type f -print | sort \
1887                | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1888
1889coccicheck:
1890        $(Q)$(BASH) $(srctree)/scripts/$@
1891
1892export_report:
1893        $(PERL) $(srctree)/scripts/export_report.pl
1894
1895PHONY += checkstack kernelrelease kernelversion image_name
1896
1897# UML needs a little special treatment here.  It wants to use the host
1898# toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
1899# else wants $(ARCH), including people doing cross-builds, which means
1900# that $(SUBARCH) doesn't work here.
1901ifeq ($(ARCH), um)
1902CHECKSTACK_ARCH := $(SUBARCH)
1903else
1904CHECKSTACK_ARCH := $(ARCH)
1905endif
1906checkstack:
1907        $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1908        $(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1909
1910kernelrelease:
1911        @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1912
1913kernelversion:
1914        @echo $(KERNELVERSION)
1915
1916image_name:
1917        @echo $(KBUILD_IMAGE)
1918
1919# Clear a bunch of variables before executing the submake
1920
1921ifeq ($(quiet),silent_)
1922tools_silent=s
1923endif
1924
1925tools/: FORCE
1926        $(Q)mkdir -p $(objtree)/tools
1927        $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1928
1929tools/%: 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
1933quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
1934      cmd_rmfiles = rm -rf $(rm-files)
1935
1936# Run depmod only if we have System.map and depmod is executable
1937quiet_cmd_depmod = DEPMOD  $(KERNELRELEASE)
1938      cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1939                   $(KERNELRELEASE)
1940
1941# read saved command lines for existing targets
1942existing-targets := $(wildcard $(sort $(targets)))
1943
1944-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
1945
1946endif # config-build
1947endif # mixed-build
1948endif # need-sub-make
1949
1950PHONY += FORCE
1951FORCE:
1952
1953# Declare the contents of the PHONY variable as phony.  We keep that
1954# information in a variable so we can use it in if_changed and friends.
1955.PHONY: $(PHONY)
1956