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   1# SPDX-License-Identifier: GPL-2.0
   2VERSION = 5
   3PATCHLEVEL = 13
   4SUBLEVEL = 19
   5EXTRAVERSION =
   6NAME = Opossums on Parade
   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 --%,$(MAKEFLAGS))),)
  98  quiet=silent_
  99  KBUILD_VERBOSE = 0
 100endif
 101
 102export quiet Q KBUILD_VERBOSE
 103
 104# Call a source code checker (by default, "sparse") as part of the
 105# C compilation.
 106#
 107# Use 'make C=1' to enable checking of only re-compiled files.
 108# Use 'make C=2' to enable checking of *all* source files, regardless
 109# of whether they are re-compiled or not.
 110#
 111# See the file "Documentation/dev-tools/sparse.rst" for more details,
 112# including where to get the "sparse" utility.
 113
 114ifeq ("$(origin C)", "command line")
 115  KBUILD_CHECKSRC = $(C)
 116endif
 117ifndef KBUILD_CHECKSRC
 118  KBUILD_CHECKSRC = 0
 119endif
 120
 121export KBUILD_CHECKSRC
 122
 123# Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
 124# directory of external module to build. Setting M= takes precedence.
 125ifeq ("$(origin M)", "command line")
 126  KBUILD_EXTMOD := $(M)
 127endif
 128
 129$(if $(word 2, $(KBUILD_EXTMOD)), \
 130        $(error building multiple external modules is not supported))
 131
 132# Remove trailing slashes
 133ifneq ($(filter %/, $(KBUILD_EXTMOD)),)
 134KBUILD_EXTMOD := $(shell dirname $(KBUILD_EXTMOD).)
 135endif
 136
 137export KBUILD_EXTMOD
 138
 139# Kbuild will save output files in the current working directory.
 140# This does not need to match to the root of the kernel source tree.
 141#
 142# For example, you can do this:
 143#
 144#  cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
 145#
 146# If you want to save output files in a different location, there are
 147# two syntaxes to specify it.
 148#
 149# 1) O=
 150# Use "make O=dir/to/store/output/files/"
 151#
 152# 2) Set KBUILD_OUTPUT
 153# Set the environment variable KBUILD_OUTPUT to point to the output directory.
 154# export KBUILD_OUTPUT=dir/to/store/output/files/; make
 155#
 156# The O= assignment takes precedence over the KBUILD_OUTPUT environment
 157# variable.
 158
 159# Do we want to change the working directory?
 160ifeq ("$(origin O)", "command line")
 161  KBUILD_OUTPUT := $(O)
 162endif
 163
 164ifneq ($(KBUILD_OUTPUT),)
 165# Make's built-in functions such as $(abspath ...), $(realpath ...) cannot
 166# expand a shell special character '~'. We use a somewhat tedious way here.
 167abs_objtree := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) && pwd)
 168$(if $(abs_objtree),, \
 169     $(error failed to create output directory "$(KBUILD_OUTPUT)"))
 170
 171# $(realpath ...) resolves symlinks
 172abs_objtree := $(realpath $(abs_objtree))
 173else
 174abs_objtree := $(CURDIR)
 175endif # ifneq ($(KBUILD_OUTPUT),)
 176
 177ifeq ($(abs_objtree),$(CURDIR))
 178# Suppress "Entering directory ..." unless we are changing the work directory.
 179MAKEFLAGS += --no-print-directory
 180else
 181need-sub-make := 1
 182endif
 183
 184this-makefile := $(lastword $(MAKEFILE_LIST))
 185abs_srctree := $(realpath $(dir $(this-makefile)))
 186
 187ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
 188$(error source directory cannot contain spaces or colons)
 189endif
 190
 191ifneq ($(abs_srctree),$(abs_objtree))
 192# Look for make include files relative to root of kernel src
 193#
 194# This does not become effective immediately because MAKEFLAGS is re-parsed
 195# once after the Makefile is read. We need to invoke sub-make.
 196MAKEFLAGS += --include-dir=$(abs_srctree)
 197need-sub-make := 1
 198endif
 199
 200ifneq ($(filter 3.%,$(MAKE_VERSION)),)
 201# 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
 202# We need to invoke sub-make to avoid implicit rules in the top Makefile.
 203need-sub-make := 1
 204# Cancel implicit rules for this Makefile.
 205$(this-makefile): ;
 206endif
 207
 208export abs_srctree abs_objtree
 209export sub_make_done := 1
 210
 211ifeq ($(need-sub-make),1)
 212
 213PHONY += $(MAKECMDGOALS) __sub-make
 214
 215$(filter-out $(this-makefile), $(MAKECMDGOALS)) __all: __sub-make
 216        @:
 217
 218# Invoke a second make in the output directory, passing relevant variables
 219__sub-make:
 220        $(Q)$(MAKE) -C $(abs_objtree) -f $(abs_srctree)/Makefile $(MAKECMDGOALS)
 221
 222endif # need-sub-make
 223endif # sub_make_done
 224
 225# We process the rest of the Makefile if this is the final invocation of make
 226ifeq ($(need-sub-make),)
 227
 228# Do not print "Entering directory ...",
 229# but we want to display it when entering to the output directory
 230# so that IDEs/editors are able to understand relative filenames.
 231MAKEFLAGS += --no-print-directory
 232
 233ifeq ($(abs_srctree),$(abs_objtree))
 234        # building in the source tree
 235        srctree := .
 236        building_out_of_srctree :=
 237else
 238        ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
 239                # building in a subdirectory of the source tree
 240                srctree := ..
 241        else
 242                srctree := $(abs_srctree)
 243        endif
 244        building_out_of_srctree := 1
 245endif
 246
 247ifneq ($(KBUILD_ABS_SRCTREE),)
 248srctree := $(abs_srctree)
 249endif
 250
 251objtree         := .
 252VPATH           := $(srctree)
 253
 254export building_out_of_srctree srctree objtree VPATH
 255
 256# To make sure we do not include .config for any of the *config targets
 257# catch them early, and hand them over to scripts/kconfig/Makefile
 258# It is allowed to specify more targets when calling make, including
 259# mixing *config targets and build targets.
 260# For example 'make oldconfig all'.
 261# Detect when mixed targets is specified, and make a second invocation
 262# of make so .config is not included in this case either (for *config).
 263
 264version_h := include/generated/uapi/linux/version.h
 265
 266clean-targets := %clean mrproper cleandocs
 267no-dot-config-targets := $(clean-targets) \
 268                         cscope gtags TAGS tags help% %docs check% coccicheck \
 269                         $(version_h) headers headers_% archheaders archscripts \
 270                         %asm-generic kernelversion %src-pkg dt_binding_check \
 271                         outputmakefile
 272# Installation targets should not require compiler. Unfortunately, vdso_install
 273# is an exception where build artifacts may be updated. This must be fixed.
 274no-compiler-targets := $(no-dot-config-targets) install dtbs_install \
 275                        headers_install modules_install kernelrelease image_name
 276no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease \
 277                          image_name
 278single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
 279
 280config-build    :=
 281mixed-build     :=
 282need-config     := 1
 283need-compiler   := 1
 284may-sync-config := 1
 285single-build    :=
 286
 287ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
 288        ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
 289                need-config :=
 290        endif
 291endif
 292
 293ifneq ($(filter $(no-compiler-targets), $(MAKECMDGOALS)),)
 294        ifeq ($(filter-out $(no-compiler-targets), $(MAKECMDGOALS)),)
 295                need-compiler :=
 296        endif
 297endif
 298
 299ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
 300        ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
 301                may-sync-config :=
 302        endif
 303endif
 304
 305ifneq ($(KBUILD_EXTMOD),)
 306        may-sync-config :=
 307endif
 308
 309ifeq ($(KBUILD_EXTMOD),)
 310        ifneq ($(filter %config,$(MAKECMDGOALS)),)
 311                config-build := 1
 312                ifneq ($(words $(MAKECMDGOALS)),1)
 313                        mixed-build := 1
 314                endif
 315        endif
 316endif
 317
 318# We cannot build single targets and the others at the same time
 319ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
 320        single-build := 1
 321        ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
 322                mixed-build := 1
 323        endif
 324endif
 325
 326# For "make -j clean all", "make -j mrproper defconfig all", etc.
 327ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
 328        ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
 329                mixed-build := 1
 330        endif
 331endif
 332
 333# install and modules_install need also be processed one by one
 334ifneq ($(filter install,$(MAKECMDGOALS)),)
 335        ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
 336                mixed-build := 1
 337        endif
 338endif
 339
 340ifdef mixed-build
 341# ===========================================================================
 342# We're called with mixed targets (*config and build targets).
 343# Handle them one by one.
 344
 345PHONY += $(MAKECMDGOALS) __build_one_by_one
 346
 347$(MAKECMDGOALS): __build_one_by_one
 348        @:
 349
 350__build_one_by_one:
 351        $(Q)set -e; \
 352        for i in $(MAKECMDGOALS); do \
 353                $(MAKE) -f $(srctree)/Makefile $$i; \
 354        done
 355
 356else # !mixed-build
 357
 358include $(srctree)/scripts/Kbuild.include
 359
 360# Read KERNELRELEASE from include/config/kernel.release (if it exists)
 361KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
 362KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
 363export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
 364
 365include $(srctree)/scripts/subarch.include
 366
 367# Cross compiling and selecting different set of gcc/bin-utils
 368# ---------------------------------------------------------------------------
 369#
 370# When performing cross compilation for other architectures ARCH shall be set
 371# to the target architecture. (See arch/* for the possibilities).
 372# ARCH can be set during invocation of make:
 373# make ARCH=ia64
 374# Another way is to have ARCH set in the environment.
 375# The default ARCH is the host where make is executed.
 376
 377# CROSS_COMPILE specify the prefix used for all executables used
 378# during compilation. Only gcc and related bin-utils executables
 379# are prefixed with $(CROSS_COMPILE).
 380# CROSS_COMPILE can be set on the command line
 381# make CROSS_COMPILE=ia64-linux-
 382# Alternatively CROSS_COMPILE can be set in the environment.
 383# Default value for CROSS_COMPILE is not to prefix executables
 384# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
 385ARCH            ?= $(SUBARCH)
 386
 387# Architecture as present in compile.h
 388UTS_MACHINE     := $(ARCH)
 389SRCARCH         := $(ARCH)
 390
 391# Additional ARCH settings for x86
 392ifeq ($(ARCH),i386)
 393        SRCARCH := x86
 394endif
 395ifeq ($(ARCH),x86_64)
 396        SRCARCH := x86
 397endif
 398
 399# Additional ARCH settings for sparc
 400ifeq ($(ARCH),sparc32)
 401       SRCARCH := sparc
 402endif
 403ifeq ($(ARCH),sparc64)
 404       SRCARCH := sparc
 405endif
 406
 407# Additional ARCH settings for parisc
 408ifeq ($(ARCH),parisc64)
 409       SRCARCH := parisc
 410endif
 411
 412export cross_compiling :=
 413ifneq ($(SRCARCH),$(SUBARCH))
 414cross_compiling := 1
 415endif
 416
 417KCONFIG_CONFIG  ?= .config
 418export KCONFIG_CONFIG
 419
 420# SHELL used by kbuild
 421CONFIG_SHELL := sh
 422
 423HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
 424HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
 425HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
 426
 427ifneq ($(LLVM),)
 428HOSTCC  = clang
 429HOSTCXX = clang++
 430else
 431HOSTCC  = gcc
 432HOSTCXX = g++
 433endif
 434
 435export KBUILD_USERCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
 436                              -O2 -fomit-frame-pointer -std=gnu89
 437export KBUILD_USERLDFLAGS :=
 438
 439KBUILD_HOSTCFLAGS   := $(KBUILD_USERCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
 440KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
 441KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
 442KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
 443
 444# Make variables (CC, etc...)
 445CPP             = $(CC) -E
 446ifneq ($(LLVM),)
 447CC              = clang
 448LD              = ld.lld
 449AR              = llvm-ar
 450NM              = llvm-nm
 451OBJCOPY         = llvm-objcopy
 452OBJDUMP         = llvm-objdump
 453READELF         = llvm-readelf
 454STRIP           = llvm-strip
 455else
 456CC              = $(CROSS_COMPILE)gcc
 457LD              = $(CROSS_COMPILE)ld
 458AR              = $(CROSS_COMPILE)ar
 459NM              = $(CROSS_COMPILE)nm
 460OBJCOPY         = $(CROSS_COMPILE)objcopy
 461OBJDUMP         = $(CROSS_COMPILE)objdump
 462READELF         = $(CROSS_COMPILE)readelf
 463STRIP           = $(CROSS_COMPILE)strip
 464endif
 465PAHOLE          = pahole
 466RESOLVE_BTFIDS  = $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
 467LEX             = flex
 468YACC            = bison
 469AWK             = awk
 470INSTALLKERNEL  := installkernel
 471DEPMOD          = depmod
 472PERL            = perl
 473PYTHON3         = python3
 474CHECK           = sparse
 475BASH            = bash
 476KGZIP           = gzip
 477KBZIP2          = bzip2
 478KLZOP           = lzop
 479LZMA            = lzma
 480LZ4             = lz4c
 481XZ              = xz
 482ZSTD            = zstd
 483
 484CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
 485                  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
 486NOSTDINC_FLAGS :=
 487CFLAGS_MODULE   =
 488AFLAGS_MODULE   =
 489LDFLAGS_MODULE  =
 490CFLAGS_KERNEL   =
 491AFLAGS_KERNEL   =
 492LDFLAGS_vmlinux =
 493
 494# Use USERINCLUDE when you must reference the UAPI directories only.
 495USERINCLUDE    := \
 496                -I$(srctree)/arch/$(SRCARCH)/include/uapi \
 497                -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
 498                -I$(srctree)/include/uapi \
 499                -I$(objtree)/include/generated/uapi \
 500                -include $(srctree)/include/linux/compiler-version.h \
 501                -include $(srctree)/include/linux/kconfig.h
 502
 503# Use LINUXINCLUDE when you must reference the include/ directory.
 504# Needed to be compatible with the O= option
 505LINUXINCLUDE    := \
 506                -I$(srctree)/arch/$(SRCARCH)/include \
 507                -I$(objtree)/arch/$(SRCARCH)/include/generated \
 508                $(if $(building_out_of_srctree),-I$(srctree)/include) \
 509                -I$(objtree)/include \
 510                $(USERINCLUDE)
 511
 512KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
 513KBUILD_CFLAGS   := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
 514                   -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
 515                   -Werror=implicit-function-declaration -Werror=implicit-int \
 516                   -Werror=return-type -Wno-format-security \
 517                   -std=gnu89
 518KBUILD_CPPFLAGS := -D__KERNEL__
 519KBUILD_AFLAGS_KERNEL :=
 520KBUILD_CFLAGS_KERNEL :=
 521KBUILD_AFLAGS_MODULE  := -DMODULE
 522KBUILD_CFLAGS_MODULE  := -DMODULE
 523KBUILD_LDFLAGS_MODULE :=
 524KBUILD_LDFLAGS :=
 525CLANG_FLAGS :=
 526
 527export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC
 528export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
 529export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
 530export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
 531export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
 532
 533export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
 534export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
 535export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
 536export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
 537export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
 538
 539# Files to ignore in find ... statements
 540
 541export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
 542                          -name CVS -o -name .pc -o -name .hg -o -name .git \) \
 543                          -prune -o
 544export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
 545                         --exclude CVS --exclude .pc --exclude .hg --exclude .git
 546
 547# ===========================================================================
 548# Rules shared between *config targets and build targets
 549
 550# Basic helpers built in scripts/basic/
 551PHONY += scripts_basic
 552scripts_basic:
 553        $(Q)$(MAKE) $(build)=scripts/basic
 554        $(Q)rm -f .tmp_quiet_recordmcount
 555
 556PHONY += outputmakefile
 557# Before starting out-of-tree build, make sure the source tree is clean.
 558# outputmakefile generates a Makefile in the output directory, if using a
 559# separate output directory. This allows convenient use of make in the
 560# output directory.
 561# At the same time when output Makefile generated, generate .gitignore to
 562# ignore whole output directory
 563outputmakefile:
 564ifdef building_out_of_srctree
 565        $(Q)if [ -f $(srctree)/.config -o \
 566                 -d $(srctree)/include/config -o \
 567                 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
 568                echo >&2 "***"; \
 569                echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
 570                echo >&2 "*** in $(abs_srctree)";\
 571                echo >&2 "***"; \
 572                false; \
 573        fi
 574        $(Q)ln -fsn $(srctree) source
 575        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile $(srctree)
 576        $(Q)test -e .gitignore || \
 577        { echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
 578endif
 579
 580# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
 581# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
 582# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
 583# and from include/config/auto.conf.cmd to detect the compiler upgrade.
 584CC_VERSION_TEXT = $(subst $(pound),,$(shell $(CC) --version 2>/dev/null | head -n 1))
 585
 586ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
 587ifneq ($(CROSS_COMPILE),)
 588CLANG_FLAGS     += --target=$(notdir $(CROSS_COMPILE:%-=%))
 589endif
 590ifeq ($(LLVM_IAS),1)
 591CLANG_FLAGS     += -integrated-as
 592else
 593CLANG_FLAGS     += -no-integrated-as
 594GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
 595CLANG_FLAGS     += --prefix=$(GCC_TOOLCHAIN_DIR)$(notdir $(CROSS_COMPILE))
 596endif
 597CLANG_FLAGS     += -Werror=unknown-warning-option
 598KBUILD_CFLAGS   += $(CLANG_FLAGS)
 599KBUILD_AFLAGS   += $(CLANG_FLAGS)
 600export CLANG_FLAGS
 601endif
 602
 603# Include this also for config targets because some architectures need
 604# cc-cross-prefix to determine CROSS_COMPILE.
 605ifdef need-compiler
 606include $(srctree)/scripts/Makefile.compiler
 607endif
 608
 609ifdef config-build
 610# ===========================================================================
 611# *config targets only - make sure prerequisites are updated, and descend
 612# in scripts/kconfig to make the *config target
 613
 614# Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
 615# KBUILD_DEFCONFIG may point out an alternative default configuration
 616# used for 'make defconfig'
 617include $(srctree)/arch/$(SRCARCH)/Makefile
 618export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
 619
 620config: outputmakefile scripts_basic FORCE
 621        $(Q)$(MAKE) $(build)=scripts/kconfig $@
 622
 623%config: outputmakefile scripts_basic FORCE
 624        $(Q)$(MAKE) $(build)=scripts/kconfig $@
 625
 626else #!config-build
 627# ===========================================================================
 628# Build targets only - this includes vmlinux, arch specific targets, clean
 629# targets and others. In general all targets except *config targets.
 630
 631# If building an external module we do not care about the all: rule
 632# but instead __all depend on modules
 633PHONY += all
 634ifeq ($(KBUILD_EXTMOD),)
 635__all: all
 636else
 637__all: modules
 638endif
 639
 640# Decide whether to build built-in, modular, or both.
 641# Normally, just do built-in.
 642
 643KBUILD_MODULES :=
 644KBUILD_BUILTIN := 1
 645
 646# If we have only "make modules", don't compile built-in objects.
 647ifeq ($(MAKECMDGOALS),modules)
 648  KBUILD_BUILTIN :=
 649endif
 650
 651# If we have "make <whatever> modules", compile modules
 652# in addition to whatever we do anyway.
 653# Just "make" or "make all" shall build modules as well
 654
 655ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
 656  KBUILD_MODULES := 1
 657endif
 658
 659ifeq ($(MAKECMDGOALS),)
 660  KBUILD_MODULES := 1
 661endif
 662
 663export KBUILD_MODULES KBUILD_BUILTIN
 664
 665ifdef need-config
 666include include/config/auto.conf
 667endif
 668
 669ifeq ($(KBUILD_EXTMOD),)
 670# Objects we will link into vmlinux / subdirs we need to visit
 671core-y          := init/ usr/
 672drivers-y       := drivers/ sound/
 673drivers-$(CONFIG_SAMPLES) += samples/
 674drivers-$(CONFIG_NET) += net/
 675drivers-y       += virt/
 676libs-y          := lib/
 677endif # KBUILD_EXTMOD
 678
 679# The all: target is the default when no target is given on the
 680# command line.
 681# This allow a user to issue only 'make' to build a kernel including modules
 682# Defaults to vmlinux, but the arch makefile usually adds further targets
 683all: vmlinux
 684
 685CFLAGS_GCOV     := -fprofile-arcs -ftest-coverage \
 686        $(call cc-option,-fno-tree-loop-im) \
 687        $(call cc-disable-warning,maybe-uninitialized,)
 688export CFLAGS_GCOV
 689
 690# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
 691ifdef CONFIG_FUNCTION_TRACER
 692  CC_FLAGS_FTRACE := -pg
 693endif
 694
 695RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
 696RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
 697RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
 698RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
 699RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
 700RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
 701export RETPOLINE_CFLAGS
 702export RETPOLINE_VDSO_CFLAGS
 703
 704include $(srctree)/arch/$(SRCARCH)/Makefile
 705
 706ifdef need-config
 707ifdef may-sync-config
 708# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
 709# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
 710# because some architectures define CROSS_COMPILE there.
 711include include/config/auto.conf.cmd
 712
 713$(KCONFIG_CONFIG):
 714        @echo >&2 '***'
 715        @echo >&2 '*** Configuration file "$@" not found!'
 716        @echo >&2 '***'
 717        @echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
 718        @echo >&2 '*** "make menuconfig" or "make xconfig").'
 719        @echo >&2 '***'
 720        @/bin/false
 721
 722# The actual configuration files used during the build are stored in
 723# include/generated/ and include/config/. Update them if .config is newer than
 724# include/config/auto.conf (which mirrors .config).
 725#
 726# This exploits the 'multi-target pattern rule' trick.
 727# The syncconfig should be executed only once to make all the targets.
 728# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
 729#
 730# Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
 731# so you cannot notice that Kconfig is waiting for the user input.
 732%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h: $(KCONFIG_CONFIG)
 733        $(Q)$(kecho) "  SYNC    $@"
 734        $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
 735else # !may-sync-config
 736# External modules and some install targets need include/generated/autoconf.h
 737# and include/config/auto.conf but do not care if they are up-to-date.
 738# Use auto.conf to trigger the test
 739PHONY += include/config/auto.conf
 740
 741include/config/auto.conf:
 742        $(Q)test -e include/generated/autoconf.h -a -e $@ || (          \
 743        echo >&2;                                                       \
 744        echo >&2 "  ERROR: Kernel configuration is invalid.";           \
 745        echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
 746        echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";      \
 747        echo >&2 ;                                                      \
 748        /bin/false)
 749
 750endif # may-sync-config
 751endif # need-config
 752
 753KBUILD_CFLAGS   += $(call cc-option,-fno-delete-null-pointer-checks,)
 754KBUILD_CFLAGS   += $(call cc-disable-warning,frame-address,)
 755KBUILD_CFLAGS   += $(call cc-disable-warning, format-truncation)
 756KBUILD_CFLAGS   += $(call cc-disable-warning, format-overflow)
 757KBUILD_CFLAGS   += $(call cc-disable-warning, address-of-packed-member)
 758
 759ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
 760KBUILD_CFLAGS += -O2
 761else ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3
 762KBUILD_CFLAGS += -O3
 763else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
 764KBUILD_CFLAGS += -Os
 765endif
 766
 767# Tell gcc to never replace conditional load with a non-conditional one
 768KBUILD_CFLAGS   += $(call cc-option,--param=allow-store-data-races=0)
 769KBUILD_CFLAGS   += $(call cc-option,-fno-allow-store-data-races)
 770
 771ifdef CONFIG_READABLE_ASM
 772# Disable optimizations that make assembler listings hard to read.
 773# reorder blocks reorders the control in the function
 774# ipa clone creates specialized cloned functions
 775# partial inlining inlines only parts of functions
 776KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
 777                 $(call cc-option,-fno-ipa-cp-clone,) \
 778                 $(call cc-option,-fno-partial-inlining)
 779endif
 780
 781ifneq ($(CONFIG_FRAME_WARN),0)
 782KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
 783endif
 784
 785stackp-flags-y                                    := -fno-stack-protector
 786stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
 787stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
 788
 789KBUILD_CFLAGS += $(stackp-flags-y)
 790
 791ifdef CONFIG_CC_IS_CLANG
 792KBUILD_CPPFLAGS += -Qunused-arguments
 793KBUILD_CFLAGS += -Wno-format-invalid-specifier
 794KBUILD_CFLAGS += -Wno-gnu
 795# CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
 796# source of a reference will be _MergedGlobals and not on of the whitelisted names.
 797# See modpost pattern 2
 798KBUILD_CFLAGS += -mno-global-merge
 799else
 800
 801# Warn about unmarked fall-throughs in switch statement.
 802# Disabled for clang while comment to attribute conversion happens and
 803# https://github.com/ClangBuiltLinux/linux/issues/636 is discussed.
 804KBUILD_CFLAGS += $(call cc-option,-Wimplicit-fallthrough,)
 805endif
 806
 807# These warnings generated too much noise in a regular build.
 808# Use make W=1 to enable them (see scripts/Makefile.extrawarn)
 809KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
 810
 811KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
 812ifdef CONFIG_FRAME_POINTER
 813KBUILD_CFLAGS   += -fno-omit-frame-pointer -fno-optimize-sibling-calls
 814else
 815# Some targets (ARM with Thumb2, for example), can't be built with frame
 816# pointers.  For those, we don't have FUNCTION_TRACER automatically
 817# select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
 818# incompatible with -fomit-frame-pointer with current GCC, so we don't use
 819# -fomit-frame-pointer with FUNCTION_TRACER.
 820ifndef CONFIG_FUNCTION_TRACER
 821KBUILD_CFLAGS   += -fomit-frame-pointer
 822endif
 823endif
 824
 825# Initialize all stack variables with a 0xAA pattern.
 826ifdef CONFIG_INIT_STACK_ALL_PATTERN
 827KBUILD_CFLAGS   += -ftrivial-auto-var-init=pattern
 828endif
 829
 830# Initialize all stack variables with a zero value.
 831ifdef CONFIG_INIT_STACK_ALL_ZERO
 832# Future support for zero initialization is still being debated, see
 833# https://bugs.llvm.org/show_bug.cgi?id=45497. These flags are subject to being
 834# renamed or dropped.
 835KBUILD_CFLAGS   += -ftrivial-auto-var-init=zero
 836KBUILD_CFLAGS   += -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
 837endif
 838
 839# While VLAs have been removed, GCC produces unreachable stack probes
 840# for the randomize_kstack_offset feature. Disable it for all compilers.
 841KBUILD_CFLAGS   += $(call cc-option, -fno-stack-clash-protection)
 842
 843DEBUG_CFLAGS    :=
 844
 845# Workaround for GCC versions < 5.0
 846# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61801
 847ifdef CONFIG_CC_IS_GCC
 848DEBUG_CFLAGS    += $(call cc-ifversion, -lt, 0500, $(call cc-option, -fno-var-tracking-assignments))
 849endif
 850
 851ifdef CONFIG_DEBUG_INFO
 852
 853ifdef CONFIG_DEBUG_INFO_SPLIT
 854DEBUG_CFLAGS    += -gsplit-dwarf
 855else
 856DEBUG_CFLAGS    += -g
 857endif
 858
 859ifneq ($(LLVM_IAS),1)
 860KBUILD_AFLAGS   += -Wa,-gdwarf-2
 861endif
 862
 863ifndef CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT
 864dwarf-version-$(CONFIG_DEBUG_INFO_DWARF4) := 4
 865dwarf-version-$(CONFIG_DEBUG_INFO_DWARF5) := 5
 866DEBUG_CFLAGS    += -gdwarf-$(dwarf-version-y)
 867endif
 868
 869ifdef CONFIG_DEBUG_INFO_REDUCED
 870DEBUG_CFLAGS    += $(call cc-option, -femit-struct-debug-baseonly) \
 871                   $(call cc-option,-fno-var-tracking)
 872endif
 873
 874ifdef CONFIG_DEBUG_INFO_COMPRESSED
 875DEBUG_CFLAGS    += -gz=zlib
 876KBUILD_AFLAGS   += -gz=zlib
 877KBUILD_LDFLAGS  += --compress-debug-sections=zlib
 878endif
 879
 880endif # CONFIG_DEBUG_INFO
 881
 882KBUILD_CFLAGS += $(DEBUG_CFLAGS)
 883export DEBUG_CFLAGS
 884
 885ifdef CONFIG_FUNCTION_TRACER
 886ifdef CONFIG_FTRACE_MCOUNT_USE_CC
 887  CC_FLAGS_FTRACE       += -mrecord-mcount
 888  ifdef CONFIG_HAVE_NOP_MCOUNT
 889    ifeq ($(call cc-option-yn, -mnop-mcount),y)
 890      CC_FLAGS_FTRACE   += -mnop-mcount
 891      CC_FLAGS_USING    += -DCC_USING_NOP_MCOUNT
 892    endif
 893  endif
 894endif
 895ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
 896  CC_FLAGS_USING        += -DCC_USING_NOP_MCOUNT
 897endif
 898ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
 899  ifdef CONFIG_HAVE_C_RECORDMCOUNT
 900    BUILD_C_RECORDMCOUNT := y
 901    export BUILD_C_RECORDMCOUNT
 902  endif
 903endif
 904ifdef CONFIG_HAVE_FENTRY
 905  ifeq ($(call cc-option-yn, -mfentry),y)
 906    CC_FLAGS_FTRACE     += -mfentry
 907    CC_FLAGS_USING      += -DCC_USING_FENTRY
 908  endif
 909endif
 910export CC_FLAGS_FTRACE
 911KBUILD_CFLAGS   += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
 912KBUILD_AFLAGS   += $(CC_FLAGS_USING)
 913endif
 914
 915# We trigger additional mismatches with less inlining
 916ifdef CONFIG_DEBUG_SECTION_MISMATCH
 917KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
 918endif
 919
 920ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
 921KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
 922LDFLAGS_vmlinux += --gc-sections
 923endif
 924
 925ifdef CONFIG_SHADOW_CALL_STACK
 926CC_FLAGS_SCS    := -fsanitize=shadow-call-stack
 927KBUILD_CFLAGS   += $(CC_FLAGS_SCS)
 928export CC_FLAGS_SCS
 929endif
 930
 931ifdef CONFIG_LTO_CLANG
 932ifdef CONFIG_LTO_CLANG_THIN
 933CC_FLAGS_LTO    := -flto=thin -fsplit-lto-unit
 934KBUILD_LDFLAGS  += --thinlto-cache-dir=$(extmod_prefix).thinlto-cache
 935else
 936CC_FLAGS_LTO    := -flto
 937endif
 938CC_FLAGS_LTO    += -fvisibility=hidden
 939
 940# Limit inlining across translation units to reduce binary size
 941KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
 942
 943# Check for frame size exceeding threshold during prolog/epilog insertion
 944# when using lld < 13.0.0.
 945ifneq ($(CONFIG_FRAME_WARN),0)
 946ifeq ($(shell test $(CONFIG_LLD_VERSION) -lt 130000; echo $$?),0)
 947KBUILD_LDFLAGS  += -plugin-opt=-warn-stack-size=$(CONFIG_FRAME_WARN)
 948endif
 949endif
 950endif
 951
 952ifdef CONFIG_LTO
 953KBUILD_CFLAGS   += -fno-lto $(CC_FLAGS_LTO)
 954KBUILD_AFLAGS   += -fno-lto
 955export CC_FLAGS_LTO
 956endif
 957
 958ifdef CONFIG_CFI_CLANG
 959CC_FLAGS_CFI    := -fsanitize=cfi \
 960                   -fsanitize-cfi-cross-dso \
 961                   -fno-sanitize-cfi-canonical-jump-tables \
 962                   -fno-sanitize-trap=cfi \
 963                   -fno-sanitize-blacklist
 964
 965ifdef CONFIG_CFI_PERMISSIVE
 966CC_FLAGS_CFI    += -fsanitize-recover=cfi
 967endif
 968
 969# If LTO flags are filtered out, we must also filter out CFI.
 970CC_FLAGS_LTO    += $(CC_FLAGS_CFI)
 971KBUILD_CFLAGS   += $(CC_FLAGS_CFI)
 972export CC_FLAGS_CFI
 973endif
 974
 975ifdef CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_32B
 976KBUILD_CFLAGS += -falign-functions=32
 977endif
 978
 979# arch Makefile may override CC so keep this after arch Makefile is included
 980NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
 981
 982# warn about C99 declaration after statement
 983KBUILD_CFLAGS += -Wdeclaration-after-statement
 984
 985# Variable Length Arrays (VLAs) should not be used anywhere in the kernel
 986KBUILD_CFLAGS += -Wvla
 987
 988# disable pointer signed / unsigned warnings in gcc 4.0
 989KBUILD_CFLAGS += -Wno-pointer-sign
 990
 991# disable stringop warnings in gcc 8+
 992KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
 993
 994# We'll want to enable this eventually, but it's not going away for 5.7 at least
 995KBUILD_CFLAGS += $(call cc-disable-warning, zero-length-bounds)
 996KBUILD_CFLAGS += $(call cc-disable-warning, array-bounds)
 997KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
 998
 999# Another good warning that we'll want to enable eventually
1000KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
1001
1002# Enabled with W=2, disabled by default as noisy
1003KBUILD_CFLAGS += $(call cc-disable-warning, maybe-uninitialized)
1004
1005# disable invalid "can't wrap" optimizations for signed / pointers
1006KBUILD_CFLAGS   += -fno-strict-overflow
1007
1008# Make sure -fstack-check isn't enabled (like gentoo apparently did)
1009KBUILD_CFLAGS  += -fno-stack-check
1010
1011# conserve stack if available
1012KBUILD_CFLAGS   += $(call cc-option,-fconserve-stack)
1013
1014# Prohibit date/time macros, which would make the build non-deterministic
1015KBUILD_CFLAGS   += -Werror=date-time
1016
1017# enforce correct pointer usage
1018KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)
1019
1020# Require designated initializers for all marked structures
1021KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)
1022
1023# change __FILE__ to the relative path from the srctree
1024KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
1025
1026# include additional Makefiles when needed
1027include-y                       := scripts/Makefile.extrawarn
1028include-$(CONFIG_KASAN)         += scripts/Makefile.kasan
1029include-$(CONFIG_KCSAN)         += scripts/Makefile.kcsan
1030include-$(CONFIG_UBSAN)         += scripts/Makefile.ubsan
1031include-$(CONFIG_KCOV)          += scripts/Makefile.kcov
1032include-$(CONFIG_GCC_PLUGINS)   += scripts/Makefile.gcc-plugins
1033
1034include $(addprefix $(srctree)/, $(include-y))
1035
1036# scripts/Makefile.gcc-plugins is intentionally included last.
1037# Do not add $(call cc-option,...) below this line. When you build the kernel
1038# from the clean source tree, the GCC plugins do not exist at this point.
1039
1040# Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
1041KBUILD_CPPFLAGS += $(KCPPFLAGS)
1042KBUILD_AFLAGS   += $(KAFLAGS)
1043KBUILD_CFLAGS   += $(KCFLAGS)
1044
1045KBUILD_LDFLAGS_MODULE += --build-id=sha1
1046LDFLAGS_vmlinux += --build-id=sha1
1047
1048ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1049LDFLAGS_vmlinux += $(call ld-option, -X,)
1050endif
1051
1052ifeq ($(CONFIG_RELR),y)
1053LDFLAGS_vmlinux += --pack-dyn-relocs=relr --use-android-relr-tags
1054endif
1055
1056# We never want expected sections to be placed heuristically by the
1057# linker. All sections should be explicitly named in the linker script.
1058ifdef CONFIG_LD_ORPHAN_WARN
1059LDFLAGS_vmlinux += --orphan-handling=warn
1060endif
1061
1062# Align the bit size of userspace programs with the kernel
1063KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1064KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1065
1066# make the checker run with the right architecture
1067CHECKFLAGS += --arch=$(ARCH)
1068
1069# insure the checker run with the right endianness
1070CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1071
1072# the checker needs the correct machine size
1073CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1074
1075# Default kernel image to build when no specific target is given.
1076# KBUILD_IMAGE may be overruled on the command line or
1077# set in the environment
1078# Also any assignments in arch/$(ARCH)/Makefile take precedence over
1079# this default value
1080export KBUILD_IMAGE ?= vmlinux
1081
1082#
1083# INSTALL_PATH specifies where to place the updated kernel and system map
1084# images. Default is /boot, but you can set it to other values
1085export  INSTALL_PATH ?= /boot
1086
1087#
1088# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1089# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1090# an argument if needed. Otherwise it defaults to the kernel install path
1091#
1092export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1093
1094#
1095# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1096# relocations required by build roots.  This is not defined in the
1097# makefile but the argument can be passed to make if needed.
1098#
1099
1100MODLIB  = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1101export MODLIB
1102
1103HOST_LIBELF_LIBS = $(shell pkg-config libelf --libs 2>/dev/null || echo -lelf)
1104
1105has_libelf = $(call try-run,\
1106               echo "int main() {}" | $(HOSTCC) $(KBUILD_HOSTLDFLAGS) -xc -o /dev/null $(HOST_LIBELF_LIBS) -,1,0)
1107
1108ifdef CONFIG_STACK_VALIDATION
1109  ifeq ($(has_libelf),1)
1110    objtool_target := tools/objtool FORCE
1111  else
1112    SKIP_STACK_VALIDATION := 1
1113    export SKIP_STACK_VALIDATION
1114  endif
1115endif
1116
1117PHONY += resolve_btfids_clean
1118
1119resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1120
1121# tools/bpf/resolve_btfids directory might not exist
1122# in output directory, skip its clean in that case
1123resolve_btfids_clean:
1124ifneq ($(wildcard $(resolve_btfids_O)),)
1125        $(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1126endif
1127
1128ifdef CONFIG_BPF
1129ifdef CONFIG_DEBUG_INFO_BTF
1130  ifeq ($(has_libelf),1)
1131    resolve_btfids_target := tools/bpf/resolve_btfids FORCE
1132  else
1133    ERROR_RESOLVE_BTFIDS := 1
1134  endif
1135endif # CONFIG_DEBUG_INFO_BTF
1136endif # CONFIG_BPF
1137
1138PHONY += prepare0
1139
1140export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
1141export MODORDER := $(extmod_prefix)modules.order
1142export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
1143
1144ifeq ($(KBUILD_EXTMOD),)
1145core-y          += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
1146
1147vmlinux-dirs    := $(patsubst %/,%,$(filter %/, \
1148                     $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
1149                     $(libs-y) $(libs-m)))
1150
1151vmlinux-alldirs := $(sort $(vmlinux-dirs) Documentation \
1152                     $(patsubst %/,%,$(filter %/, $(core-) \
1153                        $(drivers-) $(libs-))))
1154
1155subdir-modorder := $(addsuffix modules.order,$(filter %/, \
1156                        $(core-y) $(core-m) $(libs-y) $(libs-m) \
1157                        $(drivers-y) $(drivers-m)))
1158
1159build-dirs      := $(vmlinux-dirs)
1160clean-dirs      := $(vmlinux-alldirs)
1161
1162# Externally visible symbols (used by link-vmlinux.sh)
1163KBUILD_VMLINUX_OBJS := $(head-y) $(patsubst %/,%/built-in.a, $(core-y))
1164KBUILD_VMLINUX_OBJS += $(addsuffix built-in.a, $(filter %/, $(libs-y)))
1165ifdef CONFIG_MODULES
1166KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1167KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1168else
1169KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1170endif
1171KBUILD_VMLINUX_OBJS += $(patsubst %/,%/built-in.a, $(drivers-y))
1172
1173export KBUILD_VMLINUX_OBJS KBUILD_VMLINUX_LIBS
1174export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1175# used by scripts/Makefile.package
1176export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) LICENSES arch include scripts tools)
1177
1178vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
1179
1180# Recurse until adjust_autoksyms.sh is satisfied
1181PHONY += autoksyms_recursive
1182ifdef CONFIG_TRIM_UNUSED_KSYMS
1183# For the kernel to actually contain only the needed exported symbols,
1184# we have to build modules as well to determine what those symbols are.
1185# (this can be evaluated only once include/config/auto.conf has been included)
1186KBUILD_MODULES := 1
1187
1188autoksyms_recursive: descend modules.order
1189        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1190          "$(MAKE) -f $(srctree)/Makefile vmlinux"
1191endif
1192
1193autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1194
1195quiet_cmd_autoksyms_h = GEN     $@
1196      cmd_autoksyms_h = mkdir -p $(dir $@); \
1197                        $(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@
1198
1199$(autoksyms_h):
1200        $(call cmd,autoksyms_h)
1201
1202ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1203
1204# Final link of vmlinux with optional arch pass after final link
1205cmd_link-vmlinux =                                                 \
1206        $(CONFIG_SHELL) $< "$(LD)" "$(KBUILD_LDFLAGS)" "$(LDFLAGS_vmlinux)";    \
1207        $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1208
1209vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1210        +$(call if_changed_dep,link-vmlinux)
1211
1212targets := vmlinux
1213
1214# The actual objects are generated when descending,
1215# make sure no implicit rule kicks in
1216$(sort $(vmlinux-deps) $(subdir-modorder)): descend ;
1217
1218filechk_kernel.release = \
1219        echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1220
1221# Store (new) KERNELRELEASE string in include/config/kernel.release
1222include/config/kernel.release: FORCE
1223        $(call filechk,kernel.release)
1224
1225# Additional helpers built in scripts/
1226# Carefully list dependencies so we do not try to build scripts twice
1227# in parallel
1228PHONY += scripts
1229scripts: scripts_basic scripts_dtc
1230        $(Q)$(MAKE) $(build)=$(@)
1231
1232# Things we need to do before we recursively start building the kernel
1233# or the modules are listed in "prepare".
1234# A multi level approach is used. prepareN is processed before prepareN-1.
1235# archprepare is used in arch Makefiles and when processed asm symlink,
1236# version.h and scripts_basic is processed / created.
1237
1238PHONY += prepare archprepare
1239
1240archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1241        asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h \
1242        include/generated/autoconf.h remove-stale-files
1243
1244prepare0: archprepare
1245        $(Q)$(MAKE) $(build)=scripts/mod
1246        $(Q)$(MAKE) $(build)=.
1247
1248# All the preparing..
1249prepare: prepare0 prepare-objtool prepare-resolve_btfids
1250
1251PHONY += remove-stale-files
1252remove-stale-files:
1253        $(Q)$(srctree)/scripts/remove-stale-files
1254
1255# Support for using generic headers in asm-generic
1256asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1257
1258PHONY += asm-generic uapi-asm-generic
1259asm-generic: uapi-asm-generic
1260        $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1261        generic=include/asm-generic
1262uapi-asm-generic:
1263        $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1264        generic=include/uapi/asm-generic
1265
1266PHONY += prepare-objtool prepare-resolve_btfids
1267prepare-objtool: $(objtool_target)
1268ifeq ($(SKIP_STACK_VALIDATION),1)
1269ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
1270        @echo "error: Cannot generate __mcount_loc for CONFIG_DYNAMIC_FTRACE=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1271        @false
1272endif
1273ifdef CONFIG_UNWINDER_ORC
1274        @echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1275        @false
1276else
1277        @echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1278endif
1279endif
1280
1281prepare-resolve_btfids: $(resolve_btfids_target)
1282ifeq ($(ERROR_RESOLVE_BTFIDS),1)
1283        @echo "error: Cannot resolve BTF IDs for CONFIG_DEBUG_INFO_BTF, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1284        @false
1285endif
1286# Generate some files
1287# ---------------------------------------------------------------------------
1288
1289# KERNELRELEASE can change from a few different places, meaning version.h
1290# needs to be updated, so this check is forced on all builds
1291
1292uts_len := 64
1293define filechk_utsrelease.h
1294        if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1295          echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1296          exit 1;                                                         \
1297        fi;                                                               \
1298        echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1299endef
1300
1301define filechk_version.h
1302        if [ $(SUBLEVEL) -gt 255 ]; then                                 \
1303                echo \#define LINUX_VERSION_CODE $(shell                 \
1304                expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1305        else                                                             \
1306                echo \#define LINUX_VERSION_CODE $(shell                 \
1307                expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1308        fi;                                                              \
1309        echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
1310        ((c) > 255 ? 255 : (c)))';                                       \
1311        echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
1312        echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
1313        echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1314endef
1315
1316$(version_h): PATCHLEVEL := $(if $(PATCHLEVEL), $(PATCHLEVEL), 0)
1317$(version_h): SUBLEVEL := $(if $(SUBLEVEL), $(SUBLEVEL), 0)
1318$(version_h): FORCE
1319        $(call filechk,version.h)
1320
1321include/generated/utsrelease.h: include/config/kernel.release FORCE
1322        $(call filechk,utsrelease.h)
1323
1324PHONY += headerdep
1325headerdep:
1326        $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1327        $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1328
1329# ---------------------------------------------------------------------------
1330# Kernel headers
1331
1332#Default location for installed headers
1333export INSTALL_HDR_PATH = $(objtree)/usr
1334
1335quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1336      cmd_headers_install = \
1337        mkdir -p $(INSTALL_HDR_PATH); \
1338        rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1339        usr/include $(INSTALL_HDR_PATH)
1340
1341PHONY += headers_install
1342headers_install: headers
1343        $(call cmd,headers_install)
1344
1345PHONY += archheaders archscripts
1346
1347hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1348
1349PHONY += headers
1350headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1351        $(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1352          $(error Headers not exportable for the $(SRCARCH) architecture))
1353        $(Q)$(MAKE) $(hdr-inst)=include/uapi
1354        $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1355
1356# Deprecated. It is no-op now.
1357PHONY += headers_check
1358headers_check:
1359        @echo >&2 "=================== WARNING ==================="
1360        @echo >&2 "Since Linux 5.5, 'make headers_check' is no-op,"
1361        @echo >&2 "and will be removed after Linux 5.15 release."
1362        @echo >&2 "Please remove headers_check from your scripts."
1363        @echo >&2 "==============================================="
1364
1365ifdef CONFIG_HEADERS_INSTALL
1366prepare: headers
1367endif
1368
1369PHONY += scripts_unifdef
1370scripts_unifdef: scripts_basic
1371        $(Q)$(MAKE) $(build)=scripts scripts/unifdef
1372
1373# ---------------------------------------------------------------------------
1374# Install
1375
1376# Many distributions have the custom install script, /sbin/installkernel.
1377# If DKMS is installed, 'make install' will eventually recuses back
1378# to the this Makefile to build and install external modules.
1379# Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
1380
1381install: sub_make_done :=
1382
1383# Kernel selftest
1384
1385PHONY += kselftest
1386kselftest:
1387        $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1388
1389kselftest-%: FORCE
1390        $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1391
1392PHONY += kselftest-merge
1393kselftest-merge:
1394        $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1395        $(Q)find $(srctree)/tools/testing/selftests -name config | \
1396                xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1397        $(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1398
1399# ---------------------------------------------------------------------------
1400# Devicetree files
1401
1402ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1403dtstree := arch/$(SRCARCH)/boot/dts
1404endif
1405
1406ifneq ($(dtstree),)
1407
1408%.dtb: include/config/kernel.release scripts_dtc
1409        $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1410
1411%.dtbo: include/config/kernel.release scripts_dtc
1412        $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1413
1414PHONY += dtbs dtbs_install dtbs_check
1415dtbs: include/config/kernel.release scripts_dtc
1416        $(Q)$(MAKE) $(build)=$(dtstree)
1417
1418ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1419export CHECK_DTBS=y
1420dtbs: dt_binding_check
1421endif
1422
1423dtbs_check: dtbs
1424
1425dtbs_install:
1426        $(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1427
1428ifdef CONFIG_OF_EARLY_FLATTREE
1429all: dtbs
1430endif
1431
1432endif
1433
1434PHONY += scripts_dtc
1435scripts_dtc: scripts_basic
1436        $(Q)$(MAKE) $(build)=scripts/dtc
1437
1438ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1439export CHECK_DT_BINDING=y
1440endif
1441
1442PHONY += dt_binding_check
1443dt_binding_check: scripts_dtc
1444        $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1445
1446# ---------------------------------------------------------------------------
1447# Modules
1448
1449ifdef CONFIG_MODULES
1450
1451# By default, build modules as well
1452
1453all: modules
1454
1455# When we're building modules with modversions, we need to consider
1456# the built-in objects during the descend as well, in order to
1457# make sure the checksums are up to date before we record them.
1458ifdef CONFIG_MODVERSIONS
1459  KBUILD_BUILTIN := 1
1460endif
1461
1462# Build modules
1463#
1464# A module can be listed more than once in obj-m resulting in
1465# duplicate lines in modules.order files.  Those are removed
1466# using awk while concatenating to the final file.
1467
1468PHONY += modules
1469modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_check modules_prepare
1470
1471cmd_modules_order = $(AWK) '!x[$$0]++' $(real-prereqs) > $@
1472
1473modules.order: $(subdir-modorder) FORCE
1474        $(call if_changed,modules_order)
1475
1476targets += modules.order
1477
1478# Target to prepare building external modules
1479PHONY += modules_prepare
1480modules_prepare: prepare
1481        $(Q)$(MAKE) $(build)=scripts scripts/module.lds
1482
1483export modules_sign_only :=
1484
1485ifeq ($(CONFIG_MODULE_SIG),y)
1486PHONY += modules_sign
1487modules_sign: modules_install
1488        @:
1489
1490# modules_sign is a subset of modules_install.
1491# 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1492ifeq ($(filter modules_install,$(MAKECMDGOALS)),)
1493modules_sign_only := y
1494endif
1495endif
1496
1497modinst_pre :=
1498ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
1499modinst_pre := __modinst_pre
1500endif
1501
1502modules_install: $(modinst_pre)
1503PHONY += __modinst_pre
1504__modinst_pre:
1505        @rm -rf $(MODLIB)/kernel
1506        @rm -f $(MODLIB)/source
1507        @mkdir -p $(MODLIB)/kernel
1508        @ln -s $(abspath $(srctree)) $(MODLIB)/source
1509        @if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
1510                rm -f $(MODLIB)/build ; \
1511                ln -s $(CURDIR) $(MODLIB)/build ; \
1512        fi
1513        @sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order
1514        @cp -f modules.builtin $(MODLIB)/
1515        @cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
1516
1517endif # CONFIG_MODULES
1518
1519###
1520# Cleaning is done on three levels.
1521# make clean     Delete most generated files
1522#                Leave enough to build external modules
1523# make mrproper  Delete the current configuration, and all generated files
1524# make distclean Remove editor backup files, patch leftover files and the like
1525
1526# Directories & files removed with 'make clean'
1527CLEAN_FILES += include/ksym vmlinux.symvers modules-only.symvers \
1528               modules.builtin modules.builtin.modinfo modules.nsdeps \
1529               compile_commands.json .thinlto-cache
1530
1531# Directories & files removed with 'make mrproper'
1532MRPROPER_FILES += include/config include/generated          \
1533                  arch/$(SRCARCH)/include/generated .tmp_objdiff \
1534                  debian snap tar-install \
1535                  .config .config.old .version \
1536                  Module.symvers \
1537                  certs/signing_key.pem certs/signing_key.x509 \
1538                  certs/x509.genkey \
1539                  vmlinux-gdb.py \
1540                  *.spec
1541
1542# clean - Delete most, but leave enough to build external modules
1543#
1544clean: rm-files := $(CLEAN_FILES)
1545
1546PHONY += archclean vmlinuxclean
1547
1548vmlinuxclean:
1549        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1550        $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1551
1552clean: archclean vmlinuxclean resolve_btfids_clean
1553
1554# mrproper - Delete all generated files, including .config
1555#
1556mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1557mrproper-dirs      := $(addprefix _mrproper_,scripts)
1558
1559PHONY += $(mrproper-dirs) mrproper
1560$(mrproper-dirs):
1561        $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1562
1563mrproper: clean $(mrproper-dirs)
1564        $(call cmd,rmfiles)
1565
1566# distclean
1567#
1568PHONY += distclean
1569
1570distclean: mrproper
1571        @find . $(RCS_FIND_IGNORE) \
1572                \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1573                -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1574                -o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1575                -o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1576                -type f -print | xargs rm -f
1577
1578
1579# Packaging of the kernel to various formats
1580# ---------------------------------------------------------------------------
1581
1582%src-pkg: FORCE
1583        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1584%pkg: include/config/kernel.release FORCE
1585        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1586
1587# Brief documentation of the typical targets used
1588# ---------------------------------------------------------------------------
1589
1590boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1591boards := $(sort $(notdir $(boards)))
1592board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1593board-dirs := $(sort $(notdir $(board-dirs:/=)))
1594
1595PHONY += help
1596help:
1597        @echo  'Cleaning targets:'
1598        @echo  '  clean           - Remove most generated files but keep the config and'
1599        @echo  '                    enough build support to build external modules'
1600        @echo  '  mrproper        - Remove all generated files + config + various backup files'
1601        @echo  '  distclean       - mrproper + remove editor backup and patch files'
1602        @echo  ''
1603        @echo  'Configuration targets:'
1604        @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1605        @echo  ''
1606        @echo  'Other generic targets:'
1607        @echo  '  all             - Build all targets marked with [*]'
1608        @echo  '* vmlinux         - Build the bare kernel'
1609        @echo  '* modules         - Build all modules'
1610        @echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1611        @echo  '  dir/            - Build all files in dir and below'
1612        @echo  '  dir/file.[ois]  - Build specified target only'
1613        @echo  '  dir/file.ll     - Build the LLVM assembly file'
1614        @echo  '                    (requires compiler support for LLVM assembly generation)'
1615        @echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1616        @echo  '                    (requires a recent binutils and recent build (System.map))'
1617        @echo  '  dir/file.ko     - Build module including final link'
1618        @echo  '  modules_prepare - Set up for building external modules'
1619        @echo  '  tags/TAGS       - Generate tags file for editors'
1620        @echo  '  cscope          - Generate cscope index'
1621        @echo  '  gtags           - Generate GNU GLOBAL index'
1622        @echo  '  kernelrelease   - Output the release version string (use with make -s)'
1623        @echo  '  kernelversion   - Output the version stored in Makefile (use with make -s)'
1624        @echo  '  image_name      - Output the image name (use with make -s)'
1625        @echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1626         echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1627         echo  ''
1628        @echo  'Static analysers:'
1629        @echo  '  checkstack      - Generate a list of stack hogs'
1630        @echo  '  versioncheck    - Sanity check on version.h usage'
1631        @echo  '  includecheck    - Check for duplicate included header files'
1632        @echo  '  export_report   - List the usages of all exported symbols'
1633        @echo  '  headerdep       - Detect inclusion cycles in headers'
1634        @echo  '  coccicheck      - Check with Coccinelle'
1635        @echo  '  clang-analyzer  - Check with clang static analyzer'
1636        @echo  '  clang-tidy      - Check with clang-tidy'
1637        @echo  ''
1638        @echo  'Tools:'
1639        @echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1640        @echo  ''
1641        @echo  'Kernel selftest:'
1642        @echo  '  kselftest         - Build and run kernel selftest'
1643        @echo  '                      Build, install, and boot kernel before'
1644        @echo  '                      running kselftest on it'
1645        @echo  '                      Run as root for full coverage'
1646        @echo  '  kselftest-all     - Build kernel selftest'
1647        @echo  '  kselftest-install - Build and install kernel selftest'
1648        @echo  '  kselftest-clean   - Remove all generated kselftest files'
1649        @echo  '  kselftest-merge   - Merge all the config dependencies of'
1650        @echo  '                      kselftest to existing .config.'
1651        @echo  ''
1652        @$(if $(dtstree), \
1653                echo 'Devicetree:'; \
1654                echo '* dtbs             - Build device tree blobs for enabled boards'; \
1655                echo '  dtbs_install     - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1656                echo '  dt_binding_check - Validate device tree binding documents'; \
1657                echo '  dtbs_check       - Validate device tree source files';\
1658                echo '')
1659
1660        @echo 'Userspace tools targets:'
1661        @echo '  use "make tools/help"'
1662        @echo '  or  "cd tools; make help"'
1663        @echo  ''
1664        @echo  'Kernel packaging:'
1665        @$(MAKE) -f $(srctree)/scripts/Makefile.package help
1666        @echo  ''
1667        @echo  'Documentation targets:'
1668        @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1669        @echo  ''
1670        @echo  'Architecture specific targets ($(SRCARCH)):'
1671        @$(if $(archhelp),$(archhelp),\
1672                echo '  No architecture specific help defined for $(SRCARCH)')
1673        @echo  ''
1674        @$(if $(boards), \
1675                $(foreach b, $(boards), \
1676                printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1677                echo '')
1678        @$(if $(board-dirs), \
1679                $(foreach b, $(board-dirs), \
1680                printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1681                printf "  %-16s - Show all of the above\\n" help-boards; \
1682                echo '')
1683
1684        @echo  '  make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1685        @echo  '  make V=2   [targets] 2 => give reason for rebuild of target'
1686        @echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1687        @echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1688        @echo  '                       (sparse by default)'
1689        @echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1690        @echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1691        @echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
1692        @echo  '                1: warnings which may be relevant and do not occur too often'
1693        @echo  '                2: warnings which occur quite often but may still be relevant'
1694        @echo  '                3: more obscure warnings, can most likely be ignored'
1695        @echo  '                Multiple levels can be combined with W=12 or W=123'
1696        @echo  ''
1697        @echo  'Execute "make" or "make all" to build all targets marked with [*] '
1698        @echo  'For further info see the ./README file'
1699
1700
1701help-board-dirs := $(addprefix help-,$(board-dirs))
1702
1703help-boards: $(help-board-dirs)
1704
1705boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1706
1707$(help-board-dirs): help-%:
1708        @echo  'Architecture specific targets ($(SRCARCH) $*):'
1709        @$(if $(boards-per-dir), \
1710                $(foreach b, $(boards-per-dir), \
1711                printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1712                echo '')
1713
1714
1715# Documentation targets
1716# ---------------------------------------------------------------------------
1717DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1718               linkcheckdocs dochelp refcheckdocs
1719PHONY += $(DOC_TARGETS)
1720$(DOC_TARGETS):
1721        $(Q)$(MAKE) $(build)=Documentation $@
1722
1723# Misc
1724# ---------------------------------------------------------------------------
1725
1726PHONY += scripts_gdb
1727scripts_gdb: prepare0
1728        $(Q)$(MAKE) $(build)=scripts/gdb
1729        $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1730
1731ifdef CONFIG_GDB_SCRIPTS
1732all: scripts_gdb
1733endif
1734
1735else # KBUILD_EXTMOD
1736
1737###
1738# External module support.
1739# When building external modules the kernel used as basis is considered
1740# read-only, and no consistency checks are made and the make
1741# system is not used on the basis kernel. If updates are required
1742# in the basis kernel ordinary make commands (without M=...) must be used.
1743
1744# We are always building only modules.
1745KBUILD_BUILTIN :=
1746KBUILD_MODULES := 1
1747
1748build-dirs := $(KBUILD_EXTMOD)
1749$(MODORDER): descend
1750        @:
1751
1752compile_commands.json: $(extmod_prefix)compile_commands.json
1753PHONY += compile_commands.json
1754
1755clean-dirs := $(KBUILD_EXTMOD)
1756clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1757        $(KBUILD_EXTMOD)/compile_commands.json $(KBUILD_EXTMOD)/.thinlto-cache
1758
1759PHONY += help
1760help:
1761        @echo  '  Building external modules.'
1762        @echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1763        @echo  ''
1764        @echo  '  modules         - default target, build the module(s)'
1765        @echo  '  modules_install - install the module'
1766        @echo  '  clean           - remove generated files in module directory only'
1767        @echo  ''
1768
1769# no-op for external module builds
1770PHONY += prepare modules_prepare
1771
1772endif # KBUILD_EXTMOD
1773
1774# ---------------------------------------------------------------------------
1775# Modules
1776
1777PHONY += modules modules_install
1778
1779ifdef CONFIG_MODULES
1780
1781modules: modules_check
1782        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1783
1784PHONY += modules_check
1785modules_check: $(MODORDER)
1786        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1787
1788quiet_cmd_depmod = DEPMOD  $(MODLIB)
1789      cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1790                   $(KERNELRELEASE)
1791
1792modules_install:
1793        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1794        $(call cmd,depmod)
1795
1796else # CONFIG_MODULES
1797
1798# Modules not configured
1799# ---------------------------------------------------------------------------
1800
1801modules modules_install:
1802        @echo >&2 '***'
1803        @echo >&2 '*** The present kernel configuration has modules disabled.'
1804        @echo >&2 '*** To use the module feature, please run "make menuconfig" etc.'
1805        @echo >&2 '*** to enable CONFIG_MODULES.'
1806        @echo >&2 '***'
1807        @exit 1
1808
1809endif # CONFIG_MODULES
1810
1811# Single targets
1812# ---------------------------------------------------------------------------
1813# To build individual files in subdirectories, you can do like this:
1814#
1815#   make foo/bar/baz.s
1816#
1817# The supported suffixes for single-target are listed in 'single-targets'
1818#
1819# To build only under specific subdirectories, you can do like this:
1820#
1821#   make foo/bar/baz/
1822
1823ifdef single-build
1824
1825# .ko is special because modpost is needed
1826single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1827single-no-ko := $(sort $(patsubst %.ko,%.mod, $(MAKECMDGOALS)))
1828
1829$(single-ko): single_modpost
1830        @:
1831$(single-no-ko): descend
1832        @:
1833
1834ifeq ($(KBUILD_EXTMOD),)
1835# For the single build of in-tree modules, use a temporary file to avoid
1836# the situation of modules_install installing an invalid modules.order.
1837MODORDER := .modules.tmp
1838endif
1839
1840PHONY += single_modpost
1841single_modpost: $(single-no-ko) modules_prepare
1842        $(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$m;) } > $(MODORDER)
1843        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1844
1845KBUILD_MODULES := 1
1846
1847export KBUILD_SINGLE_TARGETS := $(addprefix $(extmod_prefix), $(single-no-ko))
1848
1849# trim unrelated directories
1850build-dirs := $(foreach d, $(build-dirs), \
1851                        $(if $(filter $(d)/%, $(KBUILD_SINGLE_TARGETS)), $(d)))
1852
1853endif
1854
1855ifndef CONFIG_MODULES
1856KBUILD_MODULES :=
1857endif
1858
1859# Handle descending into subdirectories listed in $(build-dirs)
1860# Preset locale variables to speed up the build process. Limit locale
1861# tweaks to this spot to avoid wrong language settings when running
1862# make menuconfig etc.
1863# Error messages still appears in the original language
1864PHONY += descend $(build-dirs)
1865descend: $(build-dirs)
1866$(build-dirs): prepare
1867        $(Q)$(MAKE) $(build)=$@ \
1868        single-build=$(if $(filter-out $@/, $(filter $@/%, $(KBUILD_SINGLE_TARGETS))),1) \
1869        need-builtin=1 need-modorder=1
1870
1871clean-dirs := $(addprefix _clean_, $(clean-dirs))
1872PHONY += $(clean-dirs) clean
1873$(clean-dirs):
1874        $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1875
1876clean: $(clean-dirs)
1877        $(call cmd,rmfiles)
1878        @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1879                \( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1880                -o -name '*.ko.*' \
1881                -o -name '*.dtb' -o -name '*.dtbo' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1882                -o -name '*.dwo' -o -name '*.lst' \
1883                -o -name '*.su' -o -name '*.mod' \
1884                -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1885                -o -name '*.lex.c' -o -name '*.tab.[ch]' \
1886                -o -name '*.asn1.[ch]' \
1887                -o -name '*.symtypes' -o -name 'modules.order' \
1888                -o -name '.tmp_*.o.*' \
1889                -o -name '*.c.[012]*.*' \
1890                -o -name '*.ll' \
1891                -o -name '*.gcno' \
1892                -o -name '*.*.symversions' \) -type f -print | xargs rm -f
1893
1894# Generate tags for editors
1895# ---------------------------------------------------------------------------
1896quiet_cmd_tags = GEN     $@
1897      cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1898
1899tags TAGS cscope gtags: FORCE
1900        $(call cmd,tags)
1901
1902# Script to generate missing namespace dependencies
1903# ---------------------------------------------------------------------------
1904
1905PHONY += nsdeps
1906nsdeps: export KBUILD_NSDEPS=1
1907nsdeps: modules
1908        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1909
1910# Clang Tooling
1911# ---------------------------------------------------------------------------
1912
1913quiet_cmd_gen_compile_commands = GEN     $@
1914      cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
1915
1916$(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
1917        $(if $(KBUILD_EXTMOD),,$(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)) \
1918        $(if $(CONFIG_MODULES), $(MODORDER)) FORCE
1919        $(call if_changed,gen_compile_commands)
1920
1921targets += $(extmod_prefix)compile_commands.json
1922
1923PHONY += clang-tidy clang-analyzer
1924
1925ifdef CONFIG_CC_IS_CLANG
1926quiet_cmd_clang_tools = CHECK   $<
1927      cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
1928
1929clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
1930        $(call cmd,clang_tools)
1931else
1932clang-tidy clang-analyzer:
1933        @echo "$@ requires CC=clang" >&2
1934        @false
1935endif
1936
1937# Scripts to check various things for consistency
1938# ---------------------------------------------------------------------------
1939
1940PHONY += includecheck versioncheck coccicheck export_report
1941
1942includecheck:
1943        find $(srctree)/* $(RCS_FIND_IGNORE) \
1944                -name '*.[hcS]' -type f -print | sort \
1945                | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1946
1947versioncheck:
1948        find $(srctree)/* $(RCS_FIND_IGNORE) \
1949                -name '*.[hcS]' -type f -print | sort \
1950                | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1951
1952coccicheck:
1953        $(Q)$(BASH) $(srctree)/scripts/$@
1954
1955export_report:
1956        $(PERL) $(srctree)/scripts/export_report.pl
1957
1958PHONY += checkstack kernelrelease kernelversion image_name
1959
1960# UML needs a little special treatment here.  It wants to use the host
1961# toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
1962# else wants $(ARCH), including people doing cross-builds, which means
1963# that $(SUBARCH) doesn't work here.
1964ifeq ($(ARCH), um)
1965CHECKSTACK_ARCH := $(SUBARCH)
1966else
1967CHECKSTACK_ARCH := $(ARCH)
1968endif
1969checkstack:
1970        $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1971        $(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1972
1973kernelrelease:
1974        @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1975
1976kernelversion:
1977        @echo $(KERNELVERSION)
1978
1979image_name:
1980        @echo $(KBUILD_IMAGE)
1981
1982# Clear a bunch of variables before executing the submake
1983
1984ifeq ($(quiet),silent_)
1985tools_silent=s
1986endif
1987
1988tools/: FORCE
1989        $(Q)mkdir -p $(objtree)/tools
1990        $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1991
1992tools/%: FORCE
1993        $(Q)mkdir -p $(objtree)/tools
1994        $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1995
1996quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
1997      cmd_rmfiles = rm -rf $(rm-files)
1998
1999# read saved command lines for existing targets
2000existing-targets := $(wildcard $(sort $(targets)))
2001
2002-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
2003
2004endif # config-build
2005endif # mixed-build
2006endif # need-sub-make
2007
2008PHONY += FORCE
2009FORCE:
2010
2011# Declare the contents of the PHONY variable as phony.  We keep that
2012# information in a variable so we can use it in if_changed and friends.
2013.PHONY: $(PHONY)
2014