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   1# SPDX-License-Identifier: GPL-2.0
   2VERSION = 5
   3PATCHLEVEL = 9
   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
 436OBJSIZE         = llvm-size
 437STRIP           = llvm-strip
 438else
 439CC              = $(CROSS_COMPILE)gcc
 440LD              = $(CROSS_COMPILE)ld
 441AR              = $(CROSS_COMPILE)ar
 442NM              = $(CROSS_COMPILE)nm
 443OBJCOPY         = $(CROSS_COMPILE)objcopy
 444OBJDUMP         = $(CROSS_COMPILE)objdump
 445READELF         = $(CROSS_COMPILE)readelf
 446OBJSIZE         = $(CROSS_COMPILE)size
 447STRIP           = $(CROSS_COMPILE)strip
 448endif
 449PAHOLE          = pahole
 450RESOLVE_BTFIDS  = $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
 451LEX             = flex
 452YACC            = bison
 453AWK             = awk
 454INSTALLKERNEL  := installkernel
 455DEPMOD          = /sbin/depmod
 456PERL            = perl
 457PYTHON          = python
 458PYTHON3         = python3
 459CHECK           = sparse
 460BASH            = bash
 461KGZIP           = gzip
 462KBZIP2          = bzip2
 463KLZOP           = lzop
 464LZMA            = lzma
 465LZ4             = lz4c
 466XZ              = xz
 467ZSTD            = zstd
 468
 469CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
 470                  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
 471NOSTDINC_FLAGS :=
 472CFLAGS_MODULE   =
 473AFLAGS_MODULE   =
 474LDFLAGS_MODULE  =
 475CFLAGS_KERNEL   =
 476AFLAGS_KERNEL   =
 477LDFLAGS_vmlinux =
 478
 479# Use USERINCLUDE when you must reference the UAPI directories only.
 480USERINCLUDE    := \
 481                -I$(srctree)/arch/$(SRCARCH)/include/uapi \
 482                -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
 483                -I$(srctree)/include/uapi \
 484                -I$(objtree)/include/generated/uapi \
 485                -include $(srctree)/include/linux/kconfig.h
 486
 487# Use LINUXINCLUDE when you must reference the include/ directory.
 488# Needed to be compatible with the O= option
 489LINUXINCLUDE    := \
 490                -I$(srctree)/arch/$(SRCARCH)/include \
 491                -I$(objtree)/arch/$(SRCARCH)/include/generated \
 492                $(if $(building_out_of_srctree),-I$(srctree)/include) \
 493                -I$(objtree)/include \
 494                $(USERINCLUDE)
 495
 496KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
 497KBUILD_CFLAGS   := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
 498                   -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
 499                   -Werror=implicit-function-declaration -Werror=implicit-int \
 500                   -Wno-format-security \
 501                   -std=gnu89
 502KBUILD_CPPFLAGS := -D__KERNEL__
 503KBUILD_AFLAGS_KERNEL :=
 504KBUILD_CFLAGS_KERNEL :=
 505KBUILD_AFLAGS_MODULE  := -DMODULE
 506KBUILD_CFLAGS_MODULE  := -DMODULE
 507KBUILD_LDFLAGS_MODULE :=
 508export KBUILD_LDS_MODULE := $(srctree)/scripts/module-common.lds
 509KBUILD_LDFLAGS :=
 510CLANG_FLAGS :=
 511
 512export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC
 513export CPP AR NM STRIP OBJCOPY OBJDUMP OBJSIZE READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
 514export PERL PYTHON PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
 515export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
 516export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
 517
 518export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
 519export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
 520export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN CFLAGS_KCSAN
 521export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
 522export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
 523export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
 524
 525# Files to ignore in find ... statements
 526
 527export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
 528                          -name CVS -o -name .pc -o -name .hg -o -name .git \) \
 529                          -prune -o
 530export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
 531                         --exclude CVS --exclude .pc --exclude .hg --exclude .git
 532
 533# ===========================================================================
 534# Rules shared between *config targets and build targets
 535
 536# Basic helpers built in scripts/basic/
 537PHONY += scripts_basic
 538scripts_basic:
 539        $(Q)$(MAKE) $(build)=scripts/basic
 540        $(Q)rm -f .tmp_quiet_recordmcount
 541
 542PHONY += outputmakefile
 543# Before starting out-of-tree build, make sure the source tree is clean.
 544# outputmakefile generates a Makefile in the output directory, if using a
 545# separate output directory. This allows convenient use of make in the
 546# output directory.
 547# At the same time when output Makefile generated, generate .gitignore to
 548# ignore whole output directory
 549outputmakefile:
 550ifdef building_out_of_srctree
 551        $(Q)if [ -f $(srctree)/.config -o \
 552                 -d $(srctree)/include/config -o \
 553                 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
 554                echo >&2 "***"; \
 555                echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
 556                echo >&2 "*** in $(abs_srctree)";\
 557                echo >&2 "***"; \
 558                false; \
 559        fi
 560        $(Q)ln -fsn $(srctree) source
 561        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile $(srctree)
 562        $(Q)test -e .gitignore || \
 563        { echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
 564endif
 565
 566ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),)
 567ifneq ($(CROSS_COMPILE),)
 568CLANG_FLAGS     += --target=$(notdir $(CROSS_COMPILE:%-=%))
 569GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
 570CLANG_FLAGS     += --prefix=$(GCC_TOOLCHAIN_DIR)$(notdir $(CROSS_COMPILE))
 571GCC_TOOLCHAIN   := $(realpath $(GCC_TOOLCHAIN_DIR)/..)
 572endif
 573ifneq ($(GCC_TOOLCHAIN),)
 574CLANG_FLAGS     += --gcc-toolchain=$(GCC_TOOLCHAIN)
 575endif
 576ifneq ($(LLVM_IAS),1)
 577CLANG_FLAGS     += -no-integrated-as
 578endif
 579CLANG_FLAGS     += -Werror=unknown-warning-option
 580KBUILD_CFLAGS   += $(CLANG_FLAGS)
 581KBUILD_AFLAGS   += $(CLANG_FLAGS)
 582export CLANG_FLAGS
 583endif
 584
 585# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
 586# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
 587# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
 588# and from include/config/auto.conf.cmd to detect the compiler upgrade.
 589CC_VERSION_TEXT = $(shell $(CC) --version 2>/dev/null | head -n 1)
 590
 591ifdef config-build
 592# ===========================================================================
 593# *config targets only - make sure prerequisites are updated, and descend
 594# in scripts/kconfig to make the *config target
 595
 596# Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
 597# KBUILD_DEFCONFIG may point out an alternative default configuration
 598# used for 'make defconfig'
 599include arch/$(SRCARCH)/Makefile
 600export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
 601
 602config: outputmakefile scripts_basic FORCE
 603        $(Q)$(MAKE) $(build)=scripts/kconfig $@
 604
 605%config: outputmakefile scripts_basic FORCE
 606        $(Q)$(MAKE) $(build)=scripts/kconfig $@
 607
 608else #!config-build
 609# ===========================================================================
 610# Build targets only - this includes vmlinux, arch specific targets, clean
 611# targets and others. In general all targets except *config targets.
 612
 613# If building an external module we do not care about the all: rule
 614# but instead __all depend on modules
 615PHONY += all
 616ifeq ($(KBUILD_EXTMOD),)
 617__all: all
 618else
 619__all: modules
 620endif
 621
 622# Decide whether to build built-in, modular, or both.
 623# Normally, just do built-in.
 624
 625KBUILD_MODULES :=
 626KBUILD_BUILTIN := 1
 627
 628# If we have only "make modules", don't compile built-in objects.
 629ifeq ($(MAKECMDGOALS),modules)
 630  KBUILD_BUILTIN :=
 631endif
 632
 633# If we have "make <whatever> modules", compile modules
 634# in addition to whatever we do anyway.
 635# Just "make" or "make all" shall build modules as well
 636
 637ifneq ($(filter all modules nsdeps,$(MAKECMDGOALS)),)
 638  KBUILD_MODULES := 1
 639endif
 640
 641ifeq ($(MAKECMDGOALS),)
 642  KBUILD_MODULES := 1
 643endif
 644
 645export KBUILD_MODULES KBUILD_BUILTIN
 646
 647ifdef need-config
 648include include/config/auto.conf
 649endif
 650
 651ifeq ($(KBUILD_EXTMOD),)
 652# Objects we will link into vmlinux / subdirs we need to visit
 653core-y          := init/ usr/
 654drivers-y       := drivers/ sound/
 655drivers-$(CONFIG_SAMPLES) += samples/
 656drivers-y       += net/ virt/
 657libs-y          := lib/
 658endif # KBUILD_EXTMOD
 659
 660# The all: target is the default when no target is given on the
 661# command line.
 662# This allow a user to issue only 'make' to build a kernel including modules
 663# Defaults to vmlinux, but the arch makefile usually adds further targets
 664all: vmlinux
 665
 666CFLAGS_GCOV     := -fprofile-arcs -ftest-coverage \
 667        $(call cc-option,-fno-tree-loop-im) \
 668        $(call cc-disable-warning,maybe-uninitialized,)
 669export CFLAGS_GCOV
 670
 671# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
 672ifdef CONFIG_FUNCTION_TRACER
 673  CC_FLAGS_FTRACE := -pg
 674endif
 675
 676RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
 677RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
 678RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
 679RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
 680RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
 681RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
 682export RETPOLINE_CFLAGS
 683export RETPOLINE_VDSO_CFLAGS
 684
 685include arch/$(SRCARCH)/Makefile
 686
 687ifdef need-config
 688ifdef may-sync-config
 689# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
 690# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
 691# because some architectures define CROSS_COMPILE there.
 692include include/config/auto.conf.cmd
 693
 694$(KCONFIG_CONFIG):
 695        @echo >&2 '***'
 696        @echo >&2 '*** Configuration file "$@" not found!'
 697        @echo >&2 '***'
 698        @echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
 699        @echo >&2 '*** "make menuconfig" or "make xconfig").'
 700        @echo >&2 '***'
 701        @/bin/false
 702
 703# The actual configuration files used during the build are stored in
 704# include/generated/ and include/config/. Update them if .config is newer than
 705# include/config/auto.conf (which mirrors .config).
 706#
 707# This exploits the 'multi-target pattern rule' trick.
 708# The syncconfig should be executed only once to make all the targets.
 709# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
 710%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h: $(KCONFIG_CONFIG)
 711        $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
 712else # !may-sync-config
 713# External modules and some install targets need include/generated/autoconf.h
 714# and include/config/auto.conf but do not care if they are up-to-date.
 715# Use auto.conf to trigger the test
 716PHONY += include/config/auto.conf
 717
 718include/config/auto.conf:
 719        $(Q)test -e include/generated/autoconf.h -a -e $@ || (          \
 720        echo >&2;                                                       \
 721        echo >&2 "  ERROR: Kernel configuration is invalid.";           \
 722        echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
 723        echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";      \
 724        echo >&2 ;                                                      \
 725        /bin/false)
 726
 727endif # may-sync-config
 728endif # need-config
 729
 730KBUILD_CFLAGS   += $(call cc-option,-fno-delete-null-pointer-checks,)
 731KBUILD_CFLAGS   += $(call cc-disable-warning,frame-address,)
 732KBUILD_CFLAGS   += $(call cc-disable-warning, format-truncation)
 733KBUILD_CFLAGS   += $(call cc-disable-warning, format-overflow)
 734KBUILD_CFLAGS   += $(call cc-disable-warning, address-of-packed-member)
 735
 736ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
 737KBUILD_CFLAGS += -O2
 738else ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3
 739KBUILD_CFLAGS += -O3
 740else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
 741KBUILD_CFLAGS += -Os
 742endif
 743
 744# Tell gcc to never replace conditional load with a non-conditional one
 745KBUILD_CFLAGS   += $(call cc-option,--param=allow-store-data-races=0)
 746KBUILD_CFLAGS   += $(call cc-option,-fno-allow-store-data-races)
 747
 748ifdef CONFIG_READABLE_ASM
 749# Disable optimizations that make assembler listings hard to read.
 750# reorder blocks reorders the control in the function
 751# ipa clone creates specialized cloned functions
 752# partial inlining inlines only parts of functions
 753KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
 754                 $(call cc-option,-fno-ipa-cp-clone,) \
 755                 $(call cc-option,-fno-partial-inlining)
 756endif
 757
 758ifneq ($(CONFIG_FRAME_WARN),0)
 759KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
 760endif
 761
 762stackp-flags-y                                    := -fno-stack-protector
 763stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
 764stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
 765
 766KBUILD_CFLAGS += $(stackp-flags-y)
 767
 768ifdef CONFIG_CC_IS_CLANG
 769KBUILD_CPPFLAGS += -Qunused-arguments
 770KBUILD_CFLAGS += -Wno-format-invalid-specifier
 771KBUILD_CFLAGS += -Wno-gnu
 772# CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
 773# source of a reference will be _MergedGlobals and not on of the whitelisted names.
 774# See modpost pattern 2
 775KBUILD_CFLAGS += -mno-global-merge
 776else
 777
 778# These warnings generated too much noise in a regular build.
 779# Use make W=1 to enable them (see scripts/Makefile.extrawarn)
 780KBUILD_CFLAGS += -Wno-unused-but-set-variable
 781
 782# Warn about unmarked fall-throughs in switch statement.
 783# Disabled for clang while comment to attribute conversion happens and
 784# https://github.com/ClangBuiltLinux/linux/issues/636 is discussed.
 785KBUILD_CFLAGS += $(call cc-option,-Wimplicit-fallthrough,)
 786endif
 787
 788KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
 789ifdef CONFIG_FRAME_POINTER
 790KBUILD_CFLAGS   += -fno-omit-frame-pointer -fno-optimize-sibling-calls
 791else
 792# Some targets (ARM with Thumb2, for example), can't be built with frame
 793# pointers.  For those, we don't have FUNCTION_TRACER automatically
 794# select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
 795# incompatible with -fomit-frame-pointer with current GCC, so we don't use
 796# -fomit-frame-pointer with FUNCTION_TRACER.
 797ifndef CONFIG_FUNCTION_TRACER
 798KBUILD_CFLAGS   += -fomit-frame-pointer
 799endif
 800endif
 801
 802# Initialize all stack variables with a 0xAA pattern.
 803ifdef CONFIG_INIT_STACK_ALL_PATTERN
 804KBUILD_CFLAGS   += -ftrivial-auto-var-init=pattern
 805endif
 806
 807# Initialize all stack variables with a zero value.
 808ifdef CONFIG_INIT_STACK_ALL_ZERO
 809# Future support for zero initialization is still being debated, see
 810# https://bugs.llvm.org/show_bug.cgi?id=45497. These flags are subject to being
 811# renamed or dropped.
 812KBUILD_CFLAGS   += -ftrivial-auto-var-init=zero
 813KBUILD_CFLAGS   += -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
 814endif
 815
 816DEBUG_CFLAGS    := $(call cc-option, -fno-var-tracking-assignments)
 817
 818ifdef CONFIG_DEBUG_INFO
 819ifdef CONFIG_DEBUG_INFO_SPLIT
 820DEBUG_CFLAGS    += -gsplit-dwarf
 821else
 822DEBUG_CFLAGS    += -g
 823endif
 824KBUILD_AFLAGS   += -Wa,-gdwarf-2
 825endif
 826ifdef CONFIG_DEBUG_INFO_DWARF4
 827DEBUG_CFLAGS    += -gdwarf-4
 828endif
 829
 830ifdef CONFIG_DEBUG_INFO_REDUCED
 831DEBUG_CFLAGS    += $(call cc-option, -femit-struct-debug-baseonly) \
 832                   $(call cc-option,-fno-var-tracking)
 833endif
 834
 835ifdef CONFIG_DEBUG_INFO_COMPRESSED
 836DEBUG_CFLAGS    += -gz=zlib
 837KBUILD_AFLAGS   += -gz=zlib
 838KBUILD_LDFLAGS  += --compress-debug-sections=zlib
 839endif
 840
 841KBUILD_CFLAGS += $(DEBUG_CFLAGS)
 842export DEBUG_CFLAGS
 843
 844ifdef CONFIG_FUNCTION_TRACER
 845ifdef CONFIG_FTRACE_MCOUNT_RECORD
 846  # gcc 5 supports generating the mcount tables directly
 847  ifeq ($(call cc-option-yn,-mrecord-mcount),y)
 848    CC_FLAGS_FTRACE     += -mrecord-mcount
 849    export CC_USING_RECORD_MCOUNT := 1
 850  endif
 851  ifdef CONFIG_HAVE_NOP_MCOUNT
 852    ifeq ($(call cc-option-yn, -mnop-mcount),y)
 853      CC_FLAGS_FTRACE   += -mnop-mcount
 854      CC_FLAGS_USING    += -DCC_USING_NOP_MCOUNT
 855    endif
 856  endif
 857endif
 858ifdef CONFIG_HAVE_FENTRY
 859  ifeq ($(call cc-option-yn, -mfentry),y)
 860    CC_FLAGS_FTRACE     += -mfentry
 861    CC_FLAGS_USING      += -DCC_USING_FENTRY
 862  endif
 863endif
 864export CC_FLAGS_FTRACE
 865KBUILD_CFLAGS   += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
 866KBUILD_AFLAGS   += $(CC_FLAGS_USING)
 867ifdef CONFIG_DYNAMIC_FTRACE
 868        ifdef CONFIG_HAVE_C_RECORDMCOUNT
 869                BUILD_C_RECORDMCOUNT := y
 870                export BUILD_C_RECORDMCOUNT
 871        endif
 872endif
 873endif
 874
 875# We trigger additional mismatches with less inlining
 876ifdef CONFIG_DEBUG_SECTION_MISMATCH
 877KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
 878endif
 879
 880ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
 881KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
 882LDFLAGS_vmlinux += --gc-sections
 883endif
 884
 885ifdef CONFIG_SHADOW_CALL_STACK
 886CC_FLAGS_SCS    := -fsanitize=shadow-call-stack
 887KBUILD_CFLAGS   += $(CC_FLAGS_SCS)
 888export CC_FLAGS_SCS
 889endif
 890
 891ifdef CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_32B
 892KBUILD_CFLAGS += -falign-functions=32
 893endif
 894
 895# arch Makefile may override CC so keep this after arch Makefile is included
 896NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
 897
 898# warn about C99 declaration after statement
 899KBUILD_CFLAGS += -Wdeclaration-after-statement
 900
 901# Variable Length Arrays (VLAs) should not be used anywhere in the kernel
 902KBUILD_CFLAGS += -Wvla
 903
 904# disable pointer signed / unsigned warnings in gcc 4.0
 905KBUILD_CFLAGS += -Wno-pointer-sign
 906
 907# disable stringop warnings in gcc 8+
 908KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
 909
 910# We'll want to enable this eventually, but it's not going away for 5.7 at least
 911KBUILD_CFLAGS += $(call cc-disable-warning, zero-length-bounds)
 912KBUILD_CFLAGS += $(call cc-disable-warning, array-bounds)
 913KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
 914
 915# Another good warning that we'll want to enable eventually
 916KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
 917
 918# Enabled with W=2, disabled by default as noisy
 919KBUILD_CFLAGS += $(call cc-disable-warning, maybe-uninitialized)
 920
 921# disable invalid "can't wrap" optimizations for signed / pointers
 922KBUILD_CFLAGS   += $(call cc-option,-fno-strict-overflow)
 923
 924# clang sets -fmerge-all-constants by default as optimization, but this
 925# is non-conforming behavior for C and in fact breaks the kernel, so we
 926# need to disable it here generally.
 927KBUILD_CFLAGS   += $(call cc-option,-fno-merge-all-constants)
 928
 929# for gcc -fno-merge-all-constants disables everything, but it is fine
 930# to have actual conforming behavior enabled.
 931KBUILD_CFLAGS   += $(call cc-option,-fmerge-constants)
 932
 933# Make sure -fstack-check isn't enabled (like gentoo apparently did)
 934KBUILD_CFLAGS  += $(call cc-option,-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   += $(call cc-option,-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_CFLAGS   += $(call cc-option,-fmacro-prefix-map=$(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   += $(KCFLAGS)
 975
 976KBUILD_LDFLAGS_MODULE += --build-id
 977LDFLAGS_vmlinux += --build-id
 978
 979ifeq ($(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# Align the bit size of userspace programs with the kernel
 988KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
 989KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
 990
 991# make the checker run with the right architecture
 992CHECKFLAGS += --arch=$(ARCH)
 993
 994# insure the checker run with the right endianness
 995CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
 996
 997# the checker needs the correct machine size
 998CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
 999
1000# Default kernel image to build when no specific target is given.
1001# KBUILD_IMAGE may be overruled on the command line or
1002# set in the environment
1003# Also any assignments in arch/$(ARCH)/Makefile take precedence over
1004# this default value
1005export KBUILD_IMAGE ?= vmlinux
1006
1007#
1008# INSTALL_PATH specifies where to place the updated kernel and system map
1009# images. Default is /boot, but you can set it to other values
1010export  INSTALL_PATH ?= /boot
1011
1012#
1013# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1014# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1015# an argument if needed. Otherwise it defaults to the kernel install path
1016#
1017export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1018
1019#
1020# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1021# relocations required by build roots.  This is not defined in the
1022# makefile but the argument can be passed to make if needed.
1023#
1024
1025MODLIB  = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1026export MODLIB
1027
1028#
1029# INSTALL_MOD_STRIP, if defined, will cause modules to be
1030# stripped after they are installed.  If INSTALL_MOD_STRIP is '1', then
1031# the default option --strip-debug will be used.  Otherwise,
1032# INSTALL_MOD_STRIP value will be used as the options to the strip command.
1033
1034ifdef INSTALL_MOD_STRIP
1035ifeq ($(INSTALL_MOD_STRIP),1)
1036mod_strip_cmd = $(STRIP) --strip-debug
1037else
1038mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
1039endif # INSTALL_MOD_STRIP=1
1040else
1041mod_strip_cmd = true
1042endif # INSTALL_MOD_STRIP
1043export mod_strip_cmd
1044
1045# CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
1046# after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
1047# or CONFIG_MODULE_COMPRESS_XZ.
1048
1049mod_compress_cmd = true
1050ifdef CONFIG_MODULE_COMPRESS
1051  ifdef CONFIG_MODULE_COMPRESS_GZIP
1052    mod_compress_cmd = $(KGZIP) -n -f
1053  endif # CONFIG_MODULE_COMPRESS_GZIP
1054  ifdef CONFIG_MODULE_COMPRESS_XZ
1055    mod_compress_cmd = $(XZ) -f
1056  endif # CONFIG_MODULE_COMPRESS_XZ
1057endif # CONFIG_MODULE_COMPRESS
1058export mod_compress_cmd
1059
1060ifdef CONFIG_MODULE_SIG_ALL
1061$(eval $(call config_filename,MODULE_SIG_KEY))
1062
1063mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
1064else
1065mod_sign_cmd = true
1066endif
1067export mod_sign_cmd
1068
1069HOST_LIBELF_LIBS = $(shell pkg-config libelf --libs 2>/dev/null || echo -lelf)
1070
1071has_libelf = $(call try-run,\
1072               echo "int main() {}" | $(HOSTCC) -xc -o /dev/null $(HOST_LIBELF_LIBS) -,1,0)
1073
1074ifdef CONFIG_STACK_VALIDATION
1075  ifeq ($(has_libelf),1)
1076    objtool_target := tools/objtool FORCE
1077  else
1078    SKIP_STACK_VALIDATION := 1
1079    export SKIP_STACK_VALIDATION
1080  endif
1081endif
1082
1083ifdef CONFIG_DEBUG_INFO_BTF
1084  ifeq ($(has_libelf),1)
1085    resolve_btfids_target := tools/bpf/resolve_btfids FORCE
1086  else
1087    ERROR_RESOLVE_BTFIDS := 1
1088  endif
1089endif
1090
1091PHONY += prepare0
1092
1093export MODORDER := $(extmod-prefix)modules.order
1094export MODULES_NSDEPS := $(extmod-prefix)modules.nsdeps
1095
1096ifeq ($(KBUILD_EXTMOD),)
1097core-y          += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
1098
1099vmlinux-dirs    := $(patsubst %/,%,$(filter %/, \
1100                     $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
1101                     $(libs-y) $(libs-m)))
1102
1103vmlinux-alldirs := $(sort $(vmlinux-dirs) Documentation \
1104                     $(patsubst %/,%,$(filter %/, $(core-) \
1105                        $(drivers-) $(libs-))))
1106
1107subdir-modorder := $(addsuffix modules.order,$(filter %/, \
1108                        $(core-y) $(core-m) $(libs-y) $(libs-m) \
1109                        $(drivers-y) $(drivers-m)))
1110
1111build-dirs      := $(vmlinux-dirs)
1112clean-dirs      := $(vmlinux-alldirs)
1113
1114# Externally visible symbols (used by link-vmlinux.sh)
1115KBUILD_VMLINUX_OBJS := $(head-y) $(patsubst %/,%/built-in.a, $(core-y))
1116KBUILD_VMLINUX_OBJS += $(addsuffix built-in.a, $(filter %/, $(libs-y)))
1117ifdef CONFIG_MODULES
1118KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1119KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1120else
1121KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1122endif
1123KBUILD_VMLINUX_OBJS += $(patsubst %/,%/built-in.a, $(drivers-y))
1124
1125export KBUILD_VMLINUX_OBJS KBUILD_VMLINUX_LIBS
1126export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1127# used by scripts/Makefile.package
1128export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) LICENSES arch include scripts tools)
1129
1130vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
1131
1132# Recurse until adjust_autoksyms.sh is satisfied
1133PHONY += autoksyms_recursive
1134ifdef CONFIG_TRIM_UNUSED_KSYMS
1135# For the kernel to actually contain only the needed exported symbols,
1136# we have to build modules as well to determine what those symbols are.
1137# (this can be evaluated only once include/config/auto.conf has been included)
1138KBUILD_MODULES := 1
1139
1140autoksyms_recursive: descend modules.order
1141        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1142          "$(MAKE) -f $(srctree)/Makefile vmlinux"
1143endif
1144
1145autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1146
1147quiet_cmd_autoksyms_h = GEN     $@
1148      cmd_autoksyms_h = mkdir -p $(dir $@); \
1149                        $(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@
1150
1151$(autoksyms_h):
1152        $(call cmd,autoksyms_h)
1153
1154ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1155
1156# Final link of vmlinux with optional arch pass after final link
1157cmd_link-vmlinux =                                                 \
1158        $(CONFIG_SHELL) $< "$(LD)" "$(KBUILD_LDFLAGS)" "$(LDFLAGS_vmlinux)";    \
1159        $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1160
1161vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1162        +$(call if_changed,link-vmlinux)
1163
1164targets := vmlinux
1165
1166# The actual objects are generated when descending,
1167# make sure no implicit rule kicks in
1168$(sort $(vmlinux-deps) $(subdir-modorder)): descend ;
1169
1170filechk_kernel.release = \
1171        echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1172
1173# Store (new) KERNELRELEASE string in include/config/kernel.release
1174include/config/kernel.release: FORCE
1175        $(call filechk,kernel.release)
1176
1177# Additional helpers built in scripts/
1178# Carefully list dependencies so we do not try to build scripts twice
1179# in parallel
1180PHONY += scripts
1181scripts: scripts_basic scripts_dtc
1182        $(Q)$(MAKE) $(build)=$(@)
1183
1184# Things we need to do before we recursively start building the kernel
1185# or the modules are listed in "prepare".
1186# A multi level approach is used. prepareN is processed before prepareN-1.
1187# archprepare is used in arch Makefiles and when processed asm symlink,
1188# version.h and scripts_basic is processed / created.
1189
1190PHONY += prepare archprepare
1191
1192archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1193        asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h \
1194        include/generated/autoconf.h
1195
1196prepare0: archprepare
1197        $(Q)$(MAKE) $(build)=scripts/mod
1198        $(Q)$(MAKE) $(build)=.
1199
1200# All the preparing..
1201prepare: prepare0 prepare-objtool prepare-resolve_btfids
1202
1203# Support for using generic headers in asm-generic
1204asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1205
1206PHONY += asm-generic uapi-asm-generic
1207asm-generic: uapi-asm-generic
1208        $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1209        generic=include/asm-generic
1210uapi-asm-generic:
1211        $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1212        generic=include/uapi/asm-generic
1213
1214PHONY += prepare-objtool prepare-resolve_btfids
1215prepare-objtool: $(objtool_target)
1216ifeq ($(SKIP_STACK_VALIDATION),1)
1217ifdef CONFIG_UNWINDER_ORC
1218        @echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1219        @false
1220else
1221        @echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1222endif
1223endif
1224
1225prepare-resolve_btfids: $(resolve_btfids_target)
1226ifeq ($(ERROR_RESOLVE_BTFIDS),1)
1227        @echo "error: Cannot resolve BTF IDs for CONFIG_DEBUG_INFO_BTF, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1228        @false
1229endif
1230# Generate some files
1231# ---------------------------------------------------------------------------
1232
1233# KERNELRELEASE can change from a few different places, meaning version.h
1234# needs to be updated, so this check is forced on all builds
1235
1236uts_len := 64
1237define filechk_utsrelease.h
1238        if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1239          echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1240          exit 1;                                                         \
1241        fi;                                                               \
1242        echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1243endef
1244
1245define filechk_version.h
1246        echo \#define LINUX_VERSION_CODE $(shell                         \
1247        expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1248        echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))'
1249endef
1250
1251$(version_h): FORCE
1252        $(call filechk,version.h)
1253        $(Q)rm -f $(old_version_h)
1254
1255include/generated/utsrelease.h: include/config/kernel.release FORCE
1256        $(call filechk,utsrelease.h)
1257
1258PHONY += headerdep
1259headerdep:
1260        $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1261        $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1262
1263# ---------------------------------------------------------------------------
1264# Kernel headers
1265
1266#Default location for installed headers
1267export INSTALL_HDR_PATH = $(objtree)/usr
1268
1269quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1270      cmd_headers_install = \
1271        mkdir -p $(INSTALL_HDR_PATH); \
1272        rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1273        usr/include $(INSTALL_HDR_PATH)
1274
1275PHONY += headers_install
1276headers_install: headers
1277        $(call cmd,headers_install)
1278
1279PHONY += archheaders archscripts
1280
1281hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1282
1283PHONY += headers
1284headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1285        $(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1286          $(error Headers not exportable for the $(SRCARCH) architecture))
1287        $(Q)$(MAKE) $(hdr-inst)=include/uapi
1288        $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1289
1290# Deprecated. It is no-op now.
1291PHONY += headers_check
1292headers_check:
1293        @:
1294
1295ifdef CONFIG_HEADERS_INSTALL
1296prepare: headers
1297endif
1298
1299PHONY += scripts_unifdef
1300scripts_unifdef: scripts_basic
1301        $(Q)$(MAKE) $(build)=scripts scripts/unifdef
1302
1303# ---------------------------------------------------------------------------
1304# Kernel selftest
1305
1306PHONY += kselftest
1307kselftest:
1308        $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1309
1310kselftest-%: FORCE
1311        $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1312
1313PHONY += kselftest-merge
1314kselftest-merge:
1315        $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1316        $(Q)find $(srctree)/tools/testing/selftests -name config | \
1317                xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1318        $(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1319
1320# ---------------------------------------------------------------------------
1321# Devicetree files
1322
1323ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1324dtstree := arch/$(SRCARCH)/boot/dts
1325endif
1326
1327ifneq ($(dtstree),)
1328
1329%.dtb: include/config/kernel.release scripts_dtc
1330        $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1331
1332PHONY += dtbs dtbs_install dtbs_check
1333dtbs: include/config/kernel.release scripts_dtc
1334        $(Q)$(MAKE) $(build)=$(dtstree)
1335
1336ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1337export CHECK_DTBS=y
1338dtbs: dt_binding_check
1339endif
1340
1341dtbs_check: dtbs
1342
1343dtbs_install:
1344        $(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1345
1346ifdef CONFIG_OF_EARLY_FLATTREE
1347all: dtbs
1348endif
1349
1350endif
1351
1352PHONY += scripts_dtc
1353scripts_dtc: scripts_basic
1354        $(Q)$(MAKE) $(build)=scripts/dtc
1355
1356ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1357export CHECK_DT_BINDING=y
1358endif
1359
1360PHONY += dt_binding_check
1361dt_binding_check: scripts_dtc
1362        $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1363
1364# ---------------------------------------------------------------------------
1365# Modules
1366
1367ifdef CONFIG_MODULES
1368
1369# By default, build modules as well
1370
1371all: modules
1372
1373# When we're building modules with modversions, we need to consider
1374# the built-in objects during the descend as well, in order to
1375# make sure the checksums are up to date before we record them.
1376ifdef CONFIG_MODVERSIONS
1377  KBUILD_BUILTIN := 1
1378endif
1379
1380# Build modules
1381#
1382# A module can be listed more than once in obj-m resulting in
1383# duplicate lines in modules.order files.  Those are removed
1384# using awk while concatenating to the final file.
1385
1386PHONY += modules
1387modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_check
1388        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1389
1390PHONY += modules_check
1391modules_check: modules.order
1392        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1393
1394cmd_modules_order = $(AWK) '!x[$$0]++' $(real-prereqs) > $@
1395
1396modules.order: $(subdir-modorder) FORCE
1397        $(call if_changed,modules_order)
1398
1399targets += modules.order
1400
1401# Target to prepare building external modules
1402PHONY += modules_prepare
1403modules_prepare: prepare
1404
1405# Target to install modules
1406PHONY += modules_install
1407modules_install: _modinst_ _modinst_post
1408
1409PHONY += _modinst_
1410_modinst_:
1411        @rm -rf $(MODLIB)/kernel
1412        @rm -f $(MODLIB)/source
1413        @mkdir -p $(MODLIB)/kernel
1414        @ln -s $(abspath $(srctree)) $(MODLIB)/source
1415        @if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
1416                rm -f $(MODLIB)/build ; \
1417                ln -s $(CURDIR) $(MODLIB)/build ; \
1418        fi
1419        @sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order
1420        @cp -f modules.builtin $(MODLIB)/
1421        @cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
1422        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1423
1424# This depmod is only for convenience to give the initial
1425# boot a modules.dep even before / is mounted read-write.  However the
1426# boot script depmod is the master version.
1427PHONY += _modinst_post
1428_modinst_post: _modinst_
1429        $(call cmd,depmod)
1430
1431ifeq ($(CONFIG_MODULE_SIG), y)
1432PHONY += modules_sign
1433modules_sign:
1434        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1435endif
1436
1437else # CONFIG_MODULES
1438
1439# Modules not configured
1440# ---------------------------------------------------------------------------
1441
1442PHONY += modules modules_install
1443modules modules_install:
1444        @echo >&2
1445        @echo >&2 "The present kernel configuration has modules disabled."
1446        @echo >&2 "Type 'make config' and enable loadable module support."
1447        @echo >&2 "Then build a kernel with module support enabled."
1448        @echo >&2
1449        @exit 1
1450
1451endif # CONFIG_MODULES
1452
1453###
1454# Cleaning is done on three levels.
1455# make clean     Delete most generated files
1456#                Leave enough to build external modules
1457# make mrproper  Delete the current configuration, and all generated files
1458# make distclean Remove editor backup files, patch leftover files and the like
1459
1460# Directories & files removed with 'make clean'
1461CLEAN_FILES += include/ksym vmlinux.symvers \
1462               modules.builtin modules.builtin.modinfo modules.nsdeps
1463
1464# Directories & files removed with 'make mrproper'
1465MRPROPER_FILES += include/config include/generated          \
1466                  arch/$(SRCARCH)/include/generated .tmp_objdiff \
1467                  debian snap tar-install \
1468                  .config .config.old .version \
1469                  Module.symvers \
1470                  signing_key.pem signing_key.priv signing_key.x509     \
1471                  x509.genkey extra_certificates signing_key.x509.keyid \
1472                  signing_key.x509.signer vmlinux-gdb.py \
1473                  *.spec
1474
1475# Directories & files removed with 'make distclean'
1476DISTCLEAN_FILES += tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS
1477
1478# clean - Delete most, but leave enough to build external modules
1479#
1480clean: rm-files := $(CLEAN_FILES)
1481
1482PHONY += archclean vmlinuxclean
1483
1484vmlinuxclean:
1485        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1486        $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1487
1488clean: archclean vmlinuxclean
1489
1490# mrproper - Delete all generated files, including .config
1491#
1492mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1493mrproper-dirs      := $(addprefix _mrproper_,scripts)
1494
1495PHONY += $(mrproper-dirs) mrproper
1496$(mrproper-dirs):
1497        $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1498
1499mrproper: clean $(mrproper-dirs)
1500        $(call cmd,rmfiles)
1501
1502# distclean
1503#
1504distclean: rm-files := $(wildcard $(DISTCLEAN_FILES))
1505
1506PHONY += distclean
1507
1508distclean: mrproper
1509        $(call cmd,rmfiles)
1510        @find $(srctree) $(RCS_FIND_IGNORE) \
1511                \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1512                -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1513                -o -name 'core' \) \
1514                -type f -print | xargs rm -f
1515
1516
1517# Packaging of the kernel to various formats
1518# ---------------------------------------------------------------------------
1519
1520%src-pkg: FORCE
1521        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1522%pkg: include/config/kernel.release FORCE
1523        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1524
1525# Brief documentation of the typical targets used
1526# ---------------------------------------------------------------------------
1527
1528boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1529boards := $(sort $(notdir $(boards)))
1530board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1531board-dirs := $(sort $(notdir $(board-dirs:/=)))
1532
1533PHONY += help
1534help:
1535        @echo  'Cleaning targets:'
1536        @echo  '  clean           - Remove most generated files but keep the config and'
1537        @echo  '                    enough build support to build external modules'
1538        @echo  '  mrproper        - Remove all generated files + config + various backup files'
1539        @echo  '  distclean       - mrproper + remove editor backup and patch files'
1540        @echo  ''
1541        @echo  'Configuration targets:'
1542        @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1543        @echo  ''
1544        @echo  'Other generic targets:'
1545        @echo  '  all             - Build all targets marked with [*]'
1546        @echo  '* vmlinux         - Build the bare kernel'
1547        @echo  '* modules         - Build all modules'
1548        @echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1549        @echo  '  dir/            - Build all files in dir and below'
1550        @echo  '  dir/file.[ois]  - Build specified target only'
1551        @echo  '  dir/file.ll     - Build the LLVM assembly file'
1552        @echo  '                    (requires compiler support for LLVM assembly generation)'
1553        @echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1554        @echo  '                    (requires a recent binutils and recent build (System.map))'
1555        @echo  '  dir/file.ko     - Build module including final link'
1556        @echo  '  modules_prepare - Set up for building external modules'
1557        @echo  '  tags/TAGS       - Generate tags file for editors'
1558        @echo  '  cscope          - Generate cscope index'
1559        @echo  '  gtags           - Generate GNU GLOBAL index'
1560        @echo  '  kernelrelease   - Output the release version string (use with make -s)'
1561        @echo  '  kernelversion   - Output the version stored in Makefile (use with make -s)'
1562        @echo  '  image_name      - Output the image name (use with make -s)'
1563        @echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1564         echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1565         echo  ''
1566        @echo  'Static analysers:'
1567        @echo  '  checkstack      - Generate a list of stack hogs'
1568        @echo  '  namespacecheck  - Name space analysis on compiled kernel'
1569        @echo  '  versioncheck    - Sanity check on version.h usage'
1570        @echo  '  includecheck    - Check for duplicate included header files'
1571        @echo  '  export_report   - List the usages of all exported symbols'
1572        @echo  '  headerdep       - Detect inclusion cycles in headers'
1573        @echo  '  coccicheck      - Check with Coccinelle'
1574        @echo  ''
1575        @echo  'Tools:'
1576        @echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1577        @echo  ''
1578        @echo  'Kernel selftest:'
1579        @echo  '  kselftest         - Build and run kernel selftest'
1580        @echo  '                      Build, install, and boot kernel before'
1581        @echo  '                      running kselftest on it'
1582        @echo  '                      Run as root for full coverage'
1583        @echo  '  kselftest-all     - Build kernel selftest'
1584        @echo  '  kselftest-install - Build and install kernel selftest'
1585        @echo  '  kselftest-clean   - Remove all generated kselftest files'
1586        @echo  '  kselftest-merge   - Merge all the config dependencies of'
1587        @echo  '                      kselftest to existing .config.'
1588        @echo  ''
1589        @$(if $(dtstree), \
1590                echo 'Devicetree:'; \
1591                echo '* dtbs             - Build device tree blobs for enabled boards'; \
1592                echo '  dtbs_install     - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1593                echo '  dt_binding_check - Validate device tree binding documents'; \
1594                echo '  dtbs_check       - Validate device tree source files';\
1595                echo '')
1596
1597        @echo 'Userspace tools targets:'
1598        @echo '  use "make tools/help"'
1599        @echo '  or  "cd tools; make help"'
1600        @echo  ''
1601        @echo  'Kernel packaging:'
1602        @$(MAKE) -f $(srctree)/scripts/Makefile.package help
1603        @echo  ''
1604        @echo  'Documentation targets:'
1605        @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1606        @echo  ''
1607        @echo  'Architecture specific targets ($(SRCARCH)):'
1608        @$(if $(archhelp),$(archhelp),\
1609                echo '  No architecture specific help defined for $(SRCARCH)')
1610        @echo  ''
1611        @$(if $(boards), \
1612                $(foreach b, $(boards), \
1613                printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1614                echo '')
1615        @$(if $(board-dirs), \
1616                $(foreach b, $(board-dirs), \
1617                printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1618                printf "  %-16s - Show all of the above\\n" help-boards; \
1619                echo '')
1620
1621        @echo  '  make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1622        @echo  '  make V=2   [targets] 2 => give reason for rebuild of target'
1623        @echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1624        @echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1625        @echo  '                       (sparse by default)'
1626        @echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1627        @echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1628        @echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
1629        @echo  '                1: warnings which may be relevant and do not occur too often'
1630        @echo  '                2: warnings which occur quite often but may still be relevant'
1631        @echo  '                3: more obscure warnings, can most likely be ignored'
1632        @echo  '                Multiple levels can be combined with W=12 or W=123'
1633        @echo  ''
1634        @echo  'Execute "make" or "make all" to build all targets marked with [*] '
1635        @echo  'For further info see the ./README file'
1636
1637
1638help-board-dirs := $(addprefix help-,$(board-dirs))
1639
1640help-boards: $(help-board-dirs)
1641
1642boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1643
1644$(help-board-dirs): help-%:
1645        @echo  'Architecture specific targets ($(SRCARCH) $*):'
1646        @$(if $(boards-per-dir), \
1647                $(foreach b, $(boards-per-dir), \
1648                printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1649                echo '')
1650
1651
1652# Documentation targets
1653# ---------------------------------------------------------------------------
1654DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1655               linkcheckdocs dochelp refcheckdocs
1656PHONY += $(DOC_TARGETS)
1657$(DOC_TARGETS):
1658        $(Q)$(MAKE) $(build)=Documentation $@
1659
1660# Misc
1661# ---------------------------------------------------------------------------
1662
1663PHONY += scripts_gdb
1664scripts_gdb: prepare0
1665        $(Q)$(MAKE) $(build)=scripts/gdb
1666        $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1667
1668ifdef CONFIG_GDB_SCRIPTS
1669all: scripts_gdb
1670endif
1671
1672else # KBUILD_EXTMOD
1673
1674###
1675# External module support.
1676# When building external modules the kernel used as basis is considered
1677# read-only, and no consistency checks are made and the make
1678# system is not used on the basis kernel. If updates are required
1679# in the basis kernel ordinary make commands (without M=...) must
1680# be used.
1681#
1682# The following are the only valid targets when building external
1683# modules.
1684# make M=dir clean     Delete all automatically generated files
1685# make M=dir modules   Make all modules in specified dir
1686# make M=dir           Same as 'make M=dir modules'
1687# make M=dir modules_install
1688#                      Install the modules built in the module directory
1689#                      Assumes install directory is already created
1690
1691# We are always building modules
1692KBUILD_MODULES := 1
1693
1694build-dirs := $(KBUILD_EXTMOD)
1695PHONY += modules
1696modules: descend
1697        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1698
1699PHONY += modules_install
1700modules_install: _emodinst_ _emodinst_post
1701
1702install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1703PHONY += _emodinst_
1704_emodinst_:
1705        $(Q)mkdir -p $(MODLIB)/$(install-dir)
1706        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1707
1708PHONY += _emodinst_post
1709_emodinst_post: _emodinst_
1710        $(call cmd,depmod)
1711
1712clean-dirs := $(KBUILD_EXTMOD)
1713clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps
1714
1715PHONY += help
1716help:
1717        @echo  '  Building external modules.'
1718        @echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1719        @echo  ''
1720        @echo  '  modules         - default target, build the module(s)'
1721        @echo  '  modules_install - install the module'
1722        @echo  '  clean           - remove generated files in module directory only'
1723        @echo  ''
1724
1725PHONY += prepare
1726endif # KBUILD_EXTMOD
1727
1728# Single targets
1729# ---------------------------------------------------------------------------
1730# To build individual files in subdirectories, you can do like this:
1731#
1732#   make foo/bar/baz.s
1733#
1734# The supported suffixes for single-target are listed in 'single-targets'
1735#
1736# To build only under specific subdirectories, you can do like this:
1737#
1738#   make foo/bar/baz/
1739
1740ifdef single-build
1741
1742# .ko is special because modpost is needed
1743single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1744single-no-ko := $(sort $(patsubst %.ko,%.mod, $(MAKECMDGOALS)))
1745
1746$(single-ko): single_modpost
1747        @:
1748$(single-no-ko): descend
1749        @:
1750
1751ifeq ($(KBUILD_EXTMOD),)
1752# For the single build of in-tree modules, use a temporary file to avoid
1753# the situation of modules_install installing an invalid modules.order.
1754MODORDER := .modules.tmp
1755endif
1756
1757PHONY += single_modpost
1758single_modpost: $(single-no-ko)
1759        $(Q){ $(foreach m, $(single-ko), echo $(extmod-prefix)$m;) } > $(MODORDER)
1760        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1761
1762KBUILD_MODULES := 1
1763
1764export KBUILD_SINGLE_TARGETS := $(addprefix $(extmod-prefix), $(single-no-ko))
1765
1766# trim unrelated directories
1767build-dirs := $(foreach d, $(build-dirs), \
1768                        $(if $(filter $(d)/%, $(KBUILD_SINGLE_TARGETS)), $(d)))
1769
1770endif
1771
1772ifndef CONFIG_MODULES
1773KBUILD_MODULES :=
1774endif
1775
1776# Handle descending into subdirectories listed in $(build-dirs)
1777# Preset locale variables to speed up the build process. Limit locale
1778# tweaks to this spot to avoid wrong language settings when running
1779# make menuconfig etc.
1780# Error messages still appears in the original language
1781PHONY += descend $(build-dirs)
1782descend: $(build-dirs)
1783$(build-dirs): prepare
1784        $(Q)$(MAKE) $(build)=$@ \
1785        single-build=$(if $(filter-out $@/, $(filter $@/%, $(KBUILD_SINGLE_TARGETS))),1) \
1786        need-builtin=1 need-modorder=1
1787
1788clean-dirs := $(addprefix _clean_, $(clean-dirs))
1789PHONY += $(clean-dirs) clean
1790$(clean-dirs):
1791        $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1792
1793clean: $(clean-dirs)
1794        $(call cmd,rmfiles)
1795        @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1796                \( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1797                -o -name '*.ko.*' \
1798                -o -name '*.dtb' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1799                -o -name '*.dwo' -o -name '*.lst' \
1800                -o -name '*.su' -o -name '*.mod' \
1801                -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1802                -o -name '*.lex.c' -o -name '*.tab.[ch]' \
1803                -o -name '*.asn1.[ch]' \
1804                -o -name '*.symtypes' -o -name 'modules.order' \
1805                -o -name '.tmp_*.o.*' \
1806                -o -name '*.c.[012]*.*' \
1807                -o -name '*.ll' \
1808                -o -name '*.gcno' \) -type f -print | xargs rm -f
1809
1810# Generate tags for editors
1811# ---------------------------------------------------------------------------
1812quiet_cmd_tags = GEN     $@
1813      cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1814
1815tags TAGS cscope gtags: FORCE
1816        $(call cmd,tags)
1817
1818# Script to generate missing namespace dependencies
1819# ---------------------------------------------------------------------------
1820
1821PHONY += nsdeps
1822nsdeps: export KBUILD_NSDEPS=1
1823nsdeps: modules
1824        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1825
1826# Scripts to check various things for consistency
1827# ---------------------------------------------------------------------------
1828
1829PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1830
1831includecheck:
1832        find $(srctree)/* $(RCS_FIND_IGNORE) \
1833                -name '*.[hcS]' -type f -print | sort \
1834                | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1835
1836versioncheck:
1837        find $(srctree)/* $(RCS_FIND_IGNORE) \
1838                -name '*.[hcS]' -type f -print | sort \
1839                | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1840
1841coccicheck:
1842        $(Q)$(BASH) $(srctree)/scripts/$@
1843
1844namespacecheck:
1845        $(PERL) $(srctree)/scripts/namespace.pl
1846
1847export_report:
1848        $(PERL) $(srctree)/scripts/export_report.pl
1849
1850PHONY += checkstack kernelrelease kernelversion image_name
1851
1852# UML needs a little special treatment here.  It wants to use the host
1853# toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
1854# else wants $(ARCH), including people doing cross-builds, which means
1855# that $(SUBARCH) doesn't work here.
1856ifeq ($(ARCH), um)
1857CHECKSTACK_ARCH := $(SUBARCH)
1858else
1859CHECKSTACK_ARCH := $(ARCH)
1860endif
1861checkstack:
1862        $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1863        $(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1864
1865kernelrelease:
1866        @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1867
1868kernelversion:
1869        @echo $(KERNELVERSION)
1870
1871image_name:
1872        @echo $(KBUILD_IMAGE)
1873
1874# Clear a bunch of variables before executing the submake
1875
1876ifeq ($(quiet),silent_)
1877tools_silent=s
1878endif
1879
1880tools/: FORCE
1881        $(Q)mkdir -p $(objtree)/tools
1882        $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1883
1884tools/%: FORCE
1885        $(Q)mkdir -p $(objtree)/tools
1886        $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1887
1888quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
1889      cmd_rmfiles = rm -rf $(rm-files)
1890
1891# Run depmod only if we have System.map and depmod is executable
1892quiet_cmd_depmod = DEPMOD  $(KERNELRELEASE)
1893      cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1894                   $(KERNELRELEASE)
1895
1896# read saved command lines for existing targets
1897existing-targets := $(wildcard $(sort $(targets)))
1898
1899-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
1900
1901endif # config-build
1902endif # mixed-build
1903endif # need-sub-make
1904
1905PHONY += FORCE
1906FORCE:
1907
1908# Declare the contents of the PHONY variable as phony.  We keep that
1909# information in a variable so we can use it in if_changed and friends.
1910.PHONY: $(PHONY)
1911