Makefile

   1 # SPDX-License-Identifier: GPL-2.0
   2 VERSION = 5
   3 PATCHLEVEL = 13
   4 SUBLEVEL = 0
   5 EXTRAVERSION = -rc3
   6 NAME = Frozen Wasteland
   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         $(error targets prefixed with '__' are only for internal use))
  16
  17 # That's our default target when none is given on the command line
  18 PHONY := __all
  19 __all:
  20
  21 # We are using a recursive build, so we need to do a little thinking
  22 # to get the ordering right.
  23 #
  24 # Most importantly: sub-Makefiles should only ever modify files in
  25 # their own directory. If in some directory we have a dependency on
  26 # a file in another dir (which doesn't happen often, but it's often
  27 # unavoidable when linking the built-in.a targets which finally
  28 # turn into vmlinux), we will call a sub make in that other dir, and
  29 # after that we are sure that everything which is in that other dir
  30 # is now up to date.
  31 #
  32 # The only cases where we need to modify files which have global
  33 # effects are thus separated out and done before the recursive
  34 # descending is started. They are now explicitly listed as the
  35 # prepare rule.
  36
  37 ifneq ($(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)
  41 MAKEFLAGS += -rR
  42
  43 # Avoid funny character set dependencies
  44 unexport LC_ALL
  45 LC_COLLATE=C
  46 LC_NUMERIC=C
  47 export LC_COLLATE LC_NUMERIC
  48
  49 # Avoid interference with shell env settings
  50 unexport 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 $@ :<
  71 #
  72 # If KBUILD_VERBOSE equals 0 then the above command will be hidden.
  73 # If KBUILD_VERBOSE equals 1 then the above command is displayed.
  74 # If KBUILD_VERBOSE equals 2 then give the reason why each target is rebuilt.
  75 #
  76 # To put more focus on warnings, be less verbose as default
  77 # Use 'make V=1' to see the full commands
  78
  79 ifeq ("$(origin V)", "command line")
  80   KBUILD_VERBOSE = $(V)
  81 endif
  82 ifndef KBUILD_VERBOSE
  83   KBUILD_VERBOSE = 0
  84 endif
  85
  86 ifeq ($(KBUILD_VERBOSE),1)
  87   quiet =
  88   Q =
  89 else
  90   quiet=quiet_
  91   Q = @
  92 endif
  93
  94 # If the user is running make -s (silent mode), suppress echoing of
  95 # commands
  96
  97 ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
  98   quiet=silent_
  99   KBUILD_VERBOSE = 0
 100 endif
 101
 102 export quiet Q KBUILD_VERBOSE
 103
 104 # Call a source code checker (by default, "sparse") as part of the
 105 # C compilation.
 106 #
 107 # Use 'make C=1' to enable checking of only re-compiled files.
 108 # Use 'make C=2' to enable checking of *all* source files, regardless
 109 # of whether they are re-compiled or not.
 110 #
 111 # See the file "Documentation/dev-tools/sparse.rst" for more details,
 112 # including where to get the "sparse" utility.
 113
 114 ifeq ("$(origin C)", "command line")
 115   KBUILD_CHECKSRC = $(C)
 116 endif
 117 ifndef KBUILD_CHECKSRC
 118   KBUILD_CHECKSRC = 0
 119 endif
 120
 121 export KBUILD_CHECKSRC
 122
 123 # Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
 124 # directory of external module to build. Setting M= takes precedence.
 125 ifeq ("$(origin M)", "command line")
 126   KBUILD_EXTMOD := $(M)
 127 endif
 128
 129 $(if $(word 2, $(KBUILD_EXTMOD)), \
 130         $(error building multiple external modules is not supported))
 131
 132 # Remove trailing slashes
 133 ifneq ($(filter %/, $(KBUILD_EXTMOD)),)
 134 KBUILD_EXTMOD := $(shell dirname $(KBUILD_EXTMOD).)
 135 endif
 136
 137 export KBUILD_EXTMOD
 138
 139 # Kbuild will save output files in the current working directory.
 140 # This does not need to match to the root of the kernel source tree.
 141 #
 142 # For example, you can do this:
 143 #
 144 #  cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
 145 #
 146 # If you want to save output files in a different location, there are
 147 # two syntaxes to specify it.
 148 #
 149 # 1) O=
 150 # Use "make O=dir/to/store/output/files/"
 151 #
 152 # 2) Set KBUILD_OUTPUT
 153 # Set the environment variable KBUILD_OUTPUT to point to the output directory.
 154 # export KBUILD_OUTPUT=dir/to/store/output/files/; make
 155 #
 156 # The O= assignment takes precedence over the KBUILD_OUTPUT environment
 157 # variable.
 158
 159 # Do we want to change the working directory?
 160 ifeq ("$(origin O)", "command line")
 161   KBUILD_OUTPUT := $(O)
 162 endif
 163
 164 ifneq ($(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.
 167 abs_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
 172 abs_objtree := $(realpath $(abs_objtree))
 173 else
 174 abs_objtree := $(CURDIR)
 175 endif # ifneq ($(KBUILD_OUTPUT),)
 176
 177 ifeq ($(abs_objtree),$(CURDIR))
 178 # Suppress "Entering directory ..." unless we are changing the work directory.
 179 MAKEFLAGS += --no-print-directory
 180 else
 181 need-sub-make := 1
 182 endif
 183
 184 this-makefile := $(lastword $(MAKEFILE_LIST))
 185 abs_srctree := $(realpath $(dir $(this-makefile)))
 186
 187 ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
 188 $(error source directory cannot contain spaces or colons)
 189 endif
 190
 191 ifneq ($(abs_srctree),$(abs_objtree))
 192 # Look for make include files relative to root of kernel src
 193 #
 194 # This does not become effective immediately because MAKEFLAGS is re-parsed
 195 # once after the Makefile is read. We need to invoke sub-make.
 196 MAKEFLAGS += --include-dir=$(abs_srctree)
 197 need-sub-make := 1
 198 endif
 199
 200 ifneq ($(filter 3.%,$(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.
 203 need-sub-make := 1
 204 # Cancel implicit rules for this Makefile.
 205 $(this-makefile): ;
 206 endif
 207
 208 export abs_srctree abs_objtree
 209 export sub_make_done := 1
 210
 211 ifeq ($(need-sub-make),1)
 212
 213 PHONY += $(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 $(MAKECMDGOALS)
 221
 222 endif # need-sub-make
 223 endif # sub_make_done
 224
 225 # We process the rest of the Makefile if this is the final invocation of make
 226 ifeq ($(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.
 231 MAKEFLAGS += --no-print-directory
 232
 233 ifeq ($(abs_srctree),$(abs_objtree))
 234         # building in the source tree
 235         srctree := .
 236         building_out_of_srctree :=
 237 else
 238         ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
 239                 # building in a subdirectory of the source tree
 240                 srctree := ..
 241         else
 242                 srctree := $(abs_srctree)
 243         endif
 244         building_out_of_srctree := 1
 245 endif
 246
 247 ifneq ($(KBUILD_ABS_SRCTREE),)
 248 srctree := $(abs_srctree)
 249 endif
 250
 251 objtree         := .
 252 VPATH           := $(srctree)
 253
 254 export 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
 264 version_h := include/generated/uapi/linux/version.h
 265
 266 clean-targets := %clean mrproper cleandocs
 267 no-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.
 274 no-compiler-targets := $(no-dot-config-targets) install dtbs_install \
 275                         headers_install modules_install kernelrelease image_name
 276 no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease \
 277                           image_name
 278 single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
 279
 280 config-build    :=
 281 mixed-build     :=
 282 need-config     := 1
 283 need-compiler   := 1
 284 may-sync-config := 1
 285 single-build    :=
 286
 287 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
 288         ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
 289                 need-config :=
 290         endif
 291 endif
 292
 293 ifneq ($(filter $(no-compiler-targets), $(MAKECMDGOALS)),)
 294         ifeq ($(filter-out $(no-compiler-targets), $(MAKECMDGOALS)),)
 295                 need-compiler :=
 296         endif
 297 endif
 298
 299 ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
 300         ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
 301                 may-sync-config :=
 302         endif
 303 endif
 304
 305 ifneq ($(KBUILD_EXTMOD),)
 306         may-sync-config :=
 307 endif
 308
 309 ifeq ($(KBUILD_EXTMOD),)
 310         ifneq ($(filter %config,$(MAKECMDGOALS)),)
 311                 config-build := 1
 312                 ifneq ($(words $(MAKECMDGOALS)),1)
 313                         mixed-build := 1
 314                 endif
 315         endif
 316 endif
 317
 318 # We cannot build single targets and the others at the same time
 319 ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
 320         single-build := 1
 321         ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
 322                 mixed-build := 1
 323         endif
 324 endif
 325
 326 # For "make -j clean all", "make -j mrproper defconfig all", etc.
 327 ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
 328         ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
 329                 mixed-build := 1
 330         endif
 331 endif
 332
 333 # install and modules_install need also be processed one by one
 334 ifneq ($(filter install,$(MAKECMDGOALS)),)
 335         ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
 336                 mixed-build := 1
 337         endif
 338 endif
 339
 340 ifdef mixed-build
 341 # ===========================================================================
 342 # We're called with mixed targets (*config and build targets).
 343 # Handle them one by one.
 344
 345 PHONY += $(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
 356 else # !mixed-build
 357
 358 include $(srctree)/scripts/Kbuild.include
 359
 360 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
 361 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
 362 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
 363 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
 364
 365 include $(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
 385 ARCH            ?= $(SUBARCH)
 386
 387 # Architecture as present in compile.h
 388 UTS_MACHINE     := $(ARCH)
 389 SRCARCH         := $(ARCH)
 390
 391 # Additional ARCH settings for x86
 392 ifeq ($(ARCH),i386)
 393         SRCARCH := x86
 394 endif
 395 ifeq ($(ARCH),x86_64)
 396         SRCARCH := x86
 397 endif
 398
 399 # Additional ARCH settings for sparc
 400 ifeq ($(ARCH),sparc32)
 401        SRCARCH := sparc
 402 endif
 403 ifeq ($(ARCH),sparc64)
 404        SRCARCH := sparc
 405 endif
 406
 407 export cross_compiling :=
 408 ifneq ($(SRCARCH),$(SUBARCH))
 409 cross_compiling := 1
 410 endif
 411
 412 KCONFIG_CONFIG  ?= .config
 413 export KCONFIG_CONFIG
 414
 415 # SHELL used by kbuild
 416 CONFIG_SHELL := sh
 417
 418 HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
 419 HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
 420 HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
 421
 422 ifneq ($(LLVM),)
 423 HOSTCC  = clang
 424 HOSTCXX = clang++
 425 else
 426 HOSTCC  = gcc
 427 HOSTCXX = g++
 428 endif
 429
 430 export KBUILD_USERCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
 431                               -O2 -fomit-frame-pointer -std=gnu89
 432 export KBUILD_USERLDFLAGS :=
 433
 434 KBUILD_HOSTCFLAGS   := $(KBUILD_USERCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
 435 KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
 436 KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
 437 KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
 438
 439 # Make variables (CC, etc...)
 440 CPP             = $(CC) -E
 441 ifneq ($(LLVM),)
 442 CC              = clang
 443 LD              = ld.lld
 444 AR              = llvm-ar
 445 NM              = llvm-nm
 446 OBJCOPY         = llvm-objcopy
 447 OBJDUMP         = llvm-objdump
 448 READELF         = llvm-readelf
 449 STRIP           = llvm-strip
 450 else
 451 CC              = $(CROSS_COMPILE)gcc
 452 LD              = $(CROSS_COMPILE)ld
 453 AR              = $(CROSS_COMPILE)ar
 454 NM              = $(CROSS_COMPILE)nm
 455 OBJCOPY         = $(CROSS_COMPILE)objcopy
 456 OBJDUMP         = $(CROSS_COMPILE)objdump
 457 READELF         = $(CROSS_COMPILE)readelf
 458 STRIP           = $(CROSS_COMPILE)strip
 459 endif
 460 PAHOLE          = pahole
 461 RESOLVE_BTFIDS  = $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
 462 LEX             = flex
 463 YACC            = bison
 464 AWK             = awk
 465 INSTALLKERNEL  := installkernel
 466 DEPMOD          = depmod
 467 PERL            = perl
 468 PYTHON3         = python3
 469 CHECK           = sparse
 470 BASH            = bash
 471 KGZIP           = gzip
 472 KBZIP2          = bzip2
 473 KLZOP           = lzop
 474 LZMA            = lzma
 475 LZ4             = lz4c
 476 XZ              = xz
 477 ZSTD            = zstd
 478
 479 CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
 480                   -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
 481 NOSTDINC_FLAGS :=
 482 CFLAGS_MODULE   =
 483 AFLAGS_MODULE   =
 484 LDFLAGS_MODULE  =
 485 CFLAGS_KERNEL   =
 486 AFLAGS_KERNEL   =
 487 LDFLAGS_vmlinux =
 488
 489 # Use USERINCLUDE when you must reference the UAPI directories only.
 490 USERINCLUDE    := \
 491                 -I$(srctree)/arch/$(SRCARCH)/include/uapi \
 492                 -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
 493                 -I$(srctree)/include/uapi \
 494                 -I$(objtree)/include/generated/uapi \
 495                 -include $(srctree)/include/linux/compiler-version.h \
 496                 -include $(srctree)/include/linux/kconfig.h
 497
 498 # Use LINUXINCLUDE when you must reference the include/ directory.
 499 # Needed to be compatible with the O= option
 500 LINUXINCLUDE    := \
 501                 -I$(srctree)/arch/$(SRCARCH)/include \
 502                 -I$(objtree)/arch/$(SRCARCH)/include/generated \
 503                 $(if $(building_out_of_srctree),-I$(srctree)/include) \
 504                 -I$(objtree)/include \
 505                 $(USERINCLUDE)
 506
 507 KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
 508 KBUILD_CFLAGS   := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
 509                    -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
 510                    -Werror=implicit-function-declaration -Werror=implicit-int \
 511                    -Werror=return-type -Wno-format-security \
 512                    -std=gnu89
 513 KBUILD_CPPFLAGS := -D__KERNEL__
 514 KBUILD_AFLAGS_KERNEL :=
 515 KBUILD_CFLAGS_KERNEL :=
 516 KBUILD_AFLAGS_MODULE  := -DMODULE
 517 KBUILD_CFLAGS_MODULE  := -DMODULE
 518 KBUILD_LDFLAGS_MODULE :=
 519 KBUILD_LDFLAGS :=
 520 CLANG_FLAGS :=
 521
 522 export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC
 523 export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
 524 export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
 525 export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
 526 export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
 527
 528 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
 529 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
 530 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
 531 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
 532 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
 533
 534 # Files to ignore in find ... statements
 535
 536 export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
 537                           -name CVS -o -name .pc -o -name .hg -o -name .git \) \
 538                           -prune -o
 539 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
 540                          --exclude CVS --exclude .pc --exclude .hg --exclude .git
 541
 542 # ===========================================================================
 543 # Rules shared between *config targets and build targets
 544
 545 # Basic helpers built in scripts/basic/
 546 PHONY += scripts_basic
 547 scripts_basic:
 548         $(Q)$(MAKE) $(build)=scripts/basic
 549         $(Q)rm -f .tmp_quiet_recordmcount
 550
 551 PHONY += outputmakefile
 552 ifdef building_out_of_srctree
 553 # Before starting out-of-tree build, make sure the source tree is clean.
 554 # outputmakefile generates a Makefile in the output directory, if using a
 555 # separate output directory. This allows convenient use of make in the
 556 # output directory.
 557 # At the same time when output Makefile generated, generate .gitignore to
 558 # ignore whole output directory
 559
 560 quiet_cmd_makefile = GEN     Makefile
 561       cmd_makefile = { \
 562         echo "\# Automatically generated by $(srctree)/Makefile: don't edit"; \
 563         echo "include $(srctree)/Makefile"; \
 564         } > Makefile
 565
 566 outputmakefile:
 567         $(Q)if [ -f $(srctree)/.config -o \
 568                  -d $(srctree)/include/config -o \
 569                  -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
 570                 echo >&2 "***"; \
 571                 echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
 572                 echo >&2 "*** in $(abs_srctree)";\
 573                 echo >&2 "***"; \
 574                 false; \
 575         fi
 576         $(Q)ln -fsn $(srctree) source
 577         $(call cmd,makefile)
 578         $(Q)test -e .gitignore || \
 579         { echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
 580 endif
 581
 582 # The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
 583 # Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
 584 # CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
 585 # and from include/config/auto.conf.cmd to detect the compiler upgrade.
 586 CC_VERSION_TEXT = $(subst $(pound),,$(shell $(CC) --version 2>/dev/null | head -n 1))
 587
 588 ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
 589 ifneq ($(CROSS_COMPILE),)
 590 CLANG_FLAGS     += --target=$(notdir $(CROSS_COMPILE:%-=%))
 591 endif
 592 ifeq ($(LLVM_IAS),1)
 593 CLANG_FLAGS     += -integrated-as
 594 else
 595 CLANG_FLAGS     += -no-integrated-as
 596 GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
 597 CLANG_FLAGS     += --prefix=$(GCC_TOOLCHAIN_DIR)$(notdir $(CROSS_COMPILE))
 598 endif
 599 CLANG_FLAGS     += -Werror=unknown-warning-option
 600 KBUILD_CFLAGS   += $(CLANG_FLAGS)
 601 KBUILD_AFLAGS   += $(CLANG_FLAGS)
 602 export CLANG_FLAGS
 603 endif
 604
 605 # Include this also for config targets because some architectures need
 606 # cc-cross-prefix to determine CROSS_COMPILE.
 607 ifdef need-compiler
 608 include $(srctree)/scripts/Makefile.compiler
 609 endif
 610
 611 ifdef config-build
 612 # ===========================================================================
 613 # *config targets only - make sure prerequisites are updated, and descend
 614 # in scripts/kconfig to make the *config target
 615
 616 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
 617 # KBUILD_DEFCONFIG may point out an alternative default configuration
 618 # used for 'make defconfig'
 619 include $(srctree)/arch/$(SRCARCH)/Makefile
 620 export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
 621
 622 config: outputmakefile scripts_basic FORCE
 623         $(Q)$(MAKE) $(build)=scripts/kconfig $@
 624
 625 %config: outputmakefile scripts_basic FORCE
 626         $(Q)$(MAKE) $(build)=scripts/kconfig $@
 627
 628 else #!config-build
 629 # ===========================================================================
 630 # Build targets only - this includes vmlinux, arch specific targets, clean
 631 # targets and others. In general all targets except *config targets.
 632
 633 # If building an external module we do not care about the all: rule
 634 # but instead __all depend on modules
 635 PHONY += all
 636 ifeq ($(KBUILD_EXTMOD),)
 637 __all: all
 638 else
 639 __all: modules
 640 endif
 641
 642 # Decide whether to build built-in, modular, or both.
 643 # Normally, just do built-in.
 644
 645 KBUILD_MODULES :=
 646 KBUILD_BUILTIN := 1
 647
 648 # If we have only "make modules", don't compile built-in objects.
 649 ifeq ($(MAKECMDGOALS),modules)
 650   KBUILD_BUILTIN :=
 651 endif
 652
 653 # If we have "make <whatever> modules", compile modules
 654 # in addition to whatever we do anyway.
 655 # Just "make" or "make all" shall build modules as well
 656
 657 ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
 658   KBUILD_MODULES := 1
 659 endif
 660
 661 ifeq ($(MAKECMDGOALS),)
 662   KBUILD_MODULES := 1
 663 endif
 664
 665 export KBUILD_MODULES KBUILD_BUILTIN
 666
 667 ifdef need-config
 668 include include/config/auto.conf
 669 endif
 670
 671 ifeq ($(KBUILD_EXTMOD),)
 672 # Objects we will link into vmlinux / subdirs we need to visit
 673 core-y          := init/ usr/ arch/$(SRCARCH)/
 674 drivers-y       := drivers/ sound/
 675 drivers-$(CONFIG_SAMPLES) += samples/
 676 drivers-$(CONFIG_NET) += net/
 677 drivers-y       += virt/
 678 libs-y          := lib/
 679 endif # KBUILD_EXTMOD
 680
 681 # The all: target is the default when no target is given on the
 682 # command line.
 683 # This allow a user to issue only 'make' to build a kernel including modules
 684 # Defaults to vmlinux, but the arch makefile usually adds further targets
 685 all: vmlinux
 686
 687 CFLAGS_GCOV     := -fprofile-arcs -ftest-coverage \
 688         $(call cc-option,-fno-tree-loop-im) \
 689         $(call cc-disable-warning,maybe-uninitialized,)
 690 export CFLAGS_GCOV
 691
 692 # The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
 693 ifdef CONFIG_FUNCTION_TRACER
 694   CC_FLAGS_FTRACE := -pg
 695 endif
 696
 697 RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
 698 RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
 699 RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
 700 RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
 701 RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
 702 RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
 703 export RETPOLINE_CFLAGS
 704 export RETPOLINE_VDSO_CFLAGS
 705
 706 include $(srctree)/arch/$(SRCARCH)/Makefile
 707
 708 ifdef need-config
 709 ifdef may-sync-config
 710 # Read in dependencies to all Kconfig* files, make sure to run syncconfig if
 711 # changes are detected. This should be included after arch/$(SRCARCH)/Makefile
 712 # because some architectures define CROSS_COMPILE there.
 713 include include/config/auto.conf.cmd
 714
 715 $(KCONFIG_CONFIG):
 716         @echo >&2 '***'
 717         @echo >&2 '*** Configuration file "$@" not found!'
 718         @echo >&2 '***'
 719         @echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
 720         @echo >&2 '*** "make menuconfig" or "make xconfig").'
 721         @echo >&2 '***'
 722         @/bin/false
 723
 724 # The actual configuration files used during the build are stored in
 725 # include/generated/ and include/config/. Update them if .config is newer than
 726 # include/config/auto.conf (which mirrors .config).
 727 #
 728 # This exploits the 'multi-target pattern rule' trick.
 729 # The syncconfig should be executed only once to make all the targets.
 730 # (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
 731 quiet_cmd_syncconfig = SYNC    $@
 732       cmd_syncconfig = $(MAKE) -f $(srctree)/Makefile syncconfig
 733
 734 %/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h: $(KCONFIG_CONFIG)
 735         +$(call cmd,syncconfig)
 736 else # !may-sync-config
 737 # External modules and some install targets need include/generated/autoconf.h
 738 # and include/config/auto.conf but do not care if they are up-to-date.
 739 # Use auto.conf to trigger the test
 740 PHONY += include/config/auto.conf
 741
 742 include/config/auto.conf:
 743         $(Q)test -e include/generated/autoconf.h -a -e $@ || (          \
 744         echo >&2;                                                       \
 745         echo >&2 "  ERROR: Kernel configuration is invalid.";           \
 746         echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
 747         echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";      \
 748         echo >&2 ;                                                      \
 749         /bin/false)
 750
 751 endif # may-sync-config
 752 endif # need-config
 753
 754 KBUILD_CFLAGS   += $(call cc-option,-fno-delete-null-pointer-checks,)
 755 KBUILD_CFLAGS   += $(call cc-disable-warning,frame-address,)
 756 KBUILD_CFLAGS   += $(call cc-disable-warning, format-truncation)
 757 KBUILD_CFLAGS   += $(call cc-disable-warning, format-overflow)
 758 KBUILD_CFLAGS   += $(call cc-disable-warning, address-of-packed-member)
 759
 760 ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
 761 KBUILD_CFLAGS += -O2
 762 else ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3
 763 KBUILD_CFLAGS += -O3
 764 else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
 765 KBUILD_CFLAGS += -Os
 766 endif
 767
 768 # Tell gcc to never replace conditional load with a non-conditional one
 769 KBUILD_CFLAGS   += $(call cc-option,--param=allow-store-data-races=0)
 770 KBUILD_CFLAGS   += $(call cc-option,-fno-allow-store-data-races)
 771
 772 ifdef CONFIG_READABLE_ASM
 773 # Disable optimizations that make assembler listings hard to read.
 774 # reorder blocks reorders the control in the function
 775 # ipa clone creates specialized cloned functions
 776 # partial inlining inlines only parts of functions
 777 KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
 778                  $(call cc-option,-fno-ipa-cp-clone,) \
 779                  $(call cc-option,-fno-partial-inlining)
 780 endif
 781
 782 ifneq ($(CONFIG_FRAME_WARN),0)
 783 KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
 784 endif
 785
 786 stackp-flags-y                                    := -fno-stack-protector
 787 stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
 788 stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
 789
 790 KBUILD_CFLAGS += $(stackp-flags-y)
 791
 792 ifdef CONFIG_CC_IS_CLANG
 793 KBUILD_CPPFLAGS += -Qunused-arguments
 794 KBUILD_CFLAGS += -Wno-format-invalid-specifier
 795 KBUILD_CFLAGS += -Wno-gnu
 796 # CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
 797 # source of a reference will be _MergedGlobals and not on of the whitelisted names.
 798 # See modpost pattern 2
 799 KBUILD_CFLAGS += -mno-global-merge
 800 else
 801
 802 # Warn about unmarked fall-throughs in switch statement.
 803 # Disabled for clang while comment to attribute conversion happens and
 804 # https://github.com/ClangBuiltLinux/linux/issues/636 is discussed.
 805 KBUILD_CFLAGS += $(call cc-option,-Wimplicit-fallthrough,)
 806 endif
 807
 808 # These warnings generated too much noise in a regular build.
 809 # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
 810 KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
 811
 812 KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
 813 ifdef CONFIG_FRAME_POINTER
 814 KBUILD_CFLAGS   += -fno-omit-frame-pointer -fno-optimize-sibling-calls
 815 else
 816 # Some targets (ARM with Thumb2, for example), can't be built with frame
 817 # pointers.  For those, we don't have FUNCTION_TRACER automatically
 818 # select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
 819 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
 820 # -fomit-frame-pointer with FUNCTION_TRACER.
 821 ifndef CONFIG_FUNCTION_TRACER
 822 KBUILD_CFLAGS   += -fomit-frame-pointer
 823 endif
 824 endif
 825
 826 # Initialize all stack variables with a 0xAA pattern.
 827 ifdef CONFIG_INIT_STACK_ALL_PATTERN
 828 KBUILD_CFLAGS   += -ftrivial-auto-var-init=pattern
 829 endif
 830
 831 # Initialize all stack variables with a zero value.
 832 ifdef CONFIG_INIT_STACK_ALL_ZERO
 833 # Future support for zero initialization is still being debated, see
 834 # https://bugs.llvm.org/show_bug.cgi?id=45497. These flags are subject to being
 835 # renamed or dropped.
 836 KBUILD_CFLAGS   += -ftrivial-auto-var-init=zero
 837 KBUILD_CFLAGS   += -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
 838 endif
 839
 840 # While VLAs have been removed, GCC produces unreachable stack probes
 841 # for the randomize_kstack_offset feature. Disable it for all compilers.
 842 KBUILD_CFLAGS   += $(call cc-option, -fno-stack-clash-protection)
 843
 844 DEBUG_CFLAGS    :=
 845
 846 # Workaround for GCC versions < 5.0
 847 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61801
 848 ifdef CONFIG_CC_IS_GCC
 849 DEBUG_CFLAGS    += $(call cc-ifversion, -lt, 0500, $(call cc-option, -fno-var-tracking-assignments))
 850 endif
 851
 852 ifdef CONFIG_DEBUG_INFO
 853
 854 ifdef CONFIG_DEBUG_INFO_SPLIT
 855 DEBUG_CFLAGS    += -gsplit-dwarf
 856 else
 857 DEBUG_CFLAGS    += -g
 858 endif
 859
 860 ifneq ($(LLVM_IAS),1)
 861 KBUILD_AFLAGS   += -Wa,-gdwarf-2
 862 endif
 863
 864 ifndef CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT
 865 dwarf-version-$(CONFIG_DEBUG_INFO_DWARF4) := 4
 866 dwarf-version-$(CONFIG_DEBUG_INFO_DWARF5) := 5
 867 DEBUG_CFLAGS    += -gdwarf-$(dwarf-version-y)
 868 endif
 869
 870 ifdef CONFIG_DEBUG_INFO_REDUCED
 871 DEBUG_CFLAGS    += $(call cc-option, -femit-struct-debug-baseonly) \
 872                    $(call cc-option,-fno-var-tracking)
 873 endif
 874
 875 ifdef CONFIG_DEBUG_INFO_COMPRESSED
 876 DEBUG_CFLAGS    += -gz=zlib
 877 KBUILD_AFLAGS   += -gz=zlib
 878 KBUILD_LDFLAGS  += --compress-debug-sections=zlib
 879 endif
 880
 881 endif # CONFIG_DEBUG_INFO
 882
 883 KBUILD_CFLAGS += $(DEBUG_CFLAGS)
 884 export DEBUG_CFLAGS
 885
 886 ifdef CONFIG_FUNCTION_TRACER
 887 ifdef CONFIG_FTRACE_MCOUNT_USE_CC
 888   CC_FLAGS_FTRACE       += -mrecord-mcount
 889   ifdef CONFIG_HAVE_NOP_MCOUNT
 890     ifeq ($(call cc-option-yn, -mnop-mcount),y)
 891       CC_FLAGS_FTRACE   += -mnop-mcount
 892       CC_FLAGS_USING    += -DCC_USING_NOP_MCOUNT
 893     endif
 894   endif
 895 endif
 896 ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
 897   CC_FLAGS_USING        += -DCC_USING_NOP_MCOUNT
 898 endif
 899 ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
 900   ifdef CONFIG_HAVE_C_RECORDMCOUNT
 901     BUILD_C_RECORDMCOUNT := y
 902     export BUILD_C_RECORDMCOUNT
 903   endif
 904 endif
 905 ifdef CONFIG_HAVE_FENTRY
 906   ifeq ($(call cc-option-yn, -mfentry),y)
 907     CC_FLAGS_FTRACE     += -mfentry
 908     CC_FLAGS_USING      += -DCC_USING_FENTRY
 909   endif
 910 endif
 911 export CC_FLAGS_FTRACE
 912 KBUILD_CFLAGS   += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
 913 KBUILD_AFLAGS   += $(CC_FLAGS_USING)
 914 endif
 915
 916 # We trigger additional mismatches with less inlining
 917 ifdef CONFIG_DEBUG_SECTION_MISMATCH
 918 KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
 919 endif
 920
 921 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
 922 KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
 923 LDFLAGS_vmlinux += --gc-sections
 924 endif
 925
 926 ifdef CONFIG_SHADOW_CALL_STACK
 927 CC_FLAGS_SCS    := -fsanitize=shadow-call-stack
 928 KBUILD_CFLAGS   += $(CC_FLAGS_SCS)
 929 export CC_FLAGS_SCS
 930 endif
 931
 932 ifdef CONFIG_LTO_CLANG
 933 ifdef CONFIG_LTO_CLANG_THIN
 934 CC_FLAGS_LTO    := -flto=thin -fsplit-lto-unit
 935 KBUILD_LDFLAGS  += --thinlto-cache-dir=$(extmod_prefix).thinlto-cache
 936 else
 937 CC_FLAGS_LTO    := -flto
 938 endif
 939 CC_FLAGS_LTO    += -fvisibility=hidden
 940
 941 # Limit inlining across translation units to reduce binary size
 942 KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
 943 endif
 944
 945 ifdef CONFIG_LTO
 946 KBUILD_CFLAGS   += -fno-lto $(CC_FLAGS_LTO)
 947 KBUILD_AFLAGS   += -fno-lto
 948 export CC_FLAGS_LTO
 949 endif
 950
 951 ifdef CONFIG_CFI_CLANG
 952 CC_FLAGS_CFI    := -fsanitize=cfi \
 953                    -fsanitize-cfi-cross-dso \
 954                    -fno-sanitize-cfi-canonical-jump-tables \
 955                    -fno-sanitize-trap=cfi \
 956                    -fno-sanitize-blacklist
 957
 958 ifdef CONFIG_CFI_PERMISSIVE
 959 CC_FLAGS_CFI    += -fsanitize-recover=cfi
 960 endif
 961
 962 # If LTO flags are filtered out, we must also filter out CFI.
 963 CC_FLAGS_LTO    += $(CC_FLAGS_CFI)
 964 KBUILD_CFLAGS   += $(CC_FLAGS_CFI)
 965 export CC_FLAGS_CFI
 966 endif
 967
 968 ifdef CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_64B
 969 KBUILD_CFLAGS += -falign-functions=64
 970 endif
 971
 972 # arch Makefile may override CC so keep this after arch Makefile is included
 973 NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
 974
 975 # warn about C99 declaration after statement
 976 KBUILD_CFLAGS += -Wdeclaration-after-statement
 977
 978 # Variable Length Arrays (VLAs) should not be used anywhere in the kernel
 979 KBUILD_CFLAGS += -Wvla
 980
 981 # disable pointer signed / unsigned warnings in gcc 4.0
 982 KBUILD_CFLAGS += -Wno-pointer-sign
 983
 984 # disable stringop warnings in gcc 8+
 985 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
 986
 987 # We'll want to enable this eventually, but it's not going away for 5.7 at least
 988 KBUILD_CFLAGS += $(call cc-disable-warning, zero-length-bounds)
 989 KBUILD_CFLAGS += $(call cc-disable-warning, array-bounds)
 990 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
 991
 992 # Another good warning that we'll want to enable eventually
 993 KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
 994
 995 # Enabled with W=2, disabled by default as noisy
 996 KBUILD_CFLAGS += $(call cc-disable-warning, maybe-uninitialized)
 997
 998 # disable invalid "can't wrap" optimizations for signed / pointers
 999 KBUILD_CFLAGS   += -fno-strict-overflow
1000
1001 # Make sure -fstack-check isn't enabled (like gentoo apparently did)
1002 KBUILD_CFLAGS  += -fno-stack-check
1003
1004 # conserve stack if available
1005 KBUILD_CFLAGS   += $(call cc-option,-fconserve-stack)
1006
1007 # Prohibit date/time macros, which would make the build non-deterministic
1008 KBUILD_CFLAGS   += -Werror=date-time
1009
1010 # enforce correct pointer usage
1011 KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)
1012
1013 # Require designated initializers for all marked structures
1014 KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)
1015
1016 # change __FILE__ to the relative path from the srctree
1017 KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
1018
1019 # include additional Makefiles when needed
1020 include-y                       := scripts/Makefile.extrawarn
1021 include-$(CONFIG_KASAN)         += scripts/Makefile.kasan
1022 include-$(CONFIG_KCSAN)         += scripts/Makefile.kcsan
1023 include-$(CONFIG_UBSAN)         += scripts/Makefile.ubsan
1024 include-$(CONFIG_KCOV)          += scripts/Makefile.kcov
1025 include-$(CONFIG_GCC_PLUGINS)   += scripts/Makefile.gcc-plugins
1026
1027 include $(addprefix $(srctree)/, $(include-y))
1028
1029 # scripts/Makefile.gcc-plugins is intentionally included last.
1030 # Do not add $(call cc-option,...) below this line. When you build the kernel
1031 # from the clean source tree, the GCC plugins do not exist at this point.
1032
1033 # Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
1034 KBUILD_CPPFLAGS += $(KCPPFLAGS)
1035 KBUILD_AFLAGS   += $(KAFLAGS)
1036 KBUILD_CFLAGS   += $(KCFLAGS)
1037
1038 KBUILD_LDFLAGS_MODULE += --build-id=sha1
1039 LDFLAGS_vmlinux += --build-id=sha1
1040
1041 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1042 LDFLAGS_vmlinux += $(call ld-option, -X,)
1043 endif
1044
1045 ifeq ($(CONFIG_RELR),y)
1046 LDFLAGS_vmlinux += --pack-dyn-relocs=relr
1047 endif
1048
1049 # We never want expected sections to be placed heuristically by the
1050 # linker. All sections should be explicitly named in the linker script.
1051 ifdef CONFIG_LD_ORPHAN_WARN
1052 LDFLAGS_vmlinux += --orphan-handling=warn
1053 endif
1054
1055 # Align the bit size of userspace programs with the kernel
1056 KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1057 KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1058
1059 # make the checker run with the right architecture
1060 CHECKFLAGS += --arch=$(ARCH)
1061
1062 # insure the checker run with the right endianness
1063 CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1064
1065 # the checker needs the correct machine size
1066 CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1067
1068 # Default kernel image to build when no specific target is given.
1069 # KBUILD_IMAGE may be overruled on the command line or
1070 # set in the environment
1071 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
1072 # this default value
1073 export KBUILD_IMAGE ?= vmlinux
1074
1075 #
1076 # INSTALL_PATH specifies where to place the updated kernel and system map
1077 # images. Default is /boot, but you can set it to other values
1078 export  INSTALL_PATH ?= /boot
1079
1080 #
1081 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1082 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1083 # an argument if needed. Otherwise it defaults to the kernel install path
1084 #
1085 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1086
1087 #
1088 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1089 # relocations required by build roots.  This is not defined in the
1090 # makefile but the argument can be passed to make if needed.
1091 #
1092
1093 MODLIB  = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1094 export MODLIB
1095
1096 PHONY += prepare0
1097
1098 export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
1099 export MODORDER := $(extmod_prefix)modules.order
1100 export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
1101
1102 ifeq ($(KBUILD_EXTMOD),)
1103 core-y          += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
1104
1105 vmlinux-dirs    := $(patsubst %/,%,$(filter %/, \
1106                      $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
1107                      $(libs-y) $(libs-m)))
1108
1109 vmlinux-alldirs := $(sort $(vmlinux-dirs) Documentation \
1110                      $(patsubst %/,%,$(filter %/, $(core-) \
1111                         $(drivers-) $(libs-))))
1112
1113 subdir-modorder := $(addsuffix modules.order,$(filter %/, \
1114                         $(core-y) $(core-m) $(libs-y) $(libs-m) \
1115                         $(drivers-y) $(drivers-m)))
1116
1117 build-dirs      := $(vmlinux-dirs)
1118 clean-dirs      := $(vmlinux-alldirs)
1119
1120 # Externally visible symbols (used by link-vmlinux.sh)
1121 KBUILD_VMLINUX_OBJS := $(head-y) $(patsubst %/,%/built-in.a, $(core-y))
1122 KBUILD_VMLINUX_OBJS += $(addsuffix built-in.a, $(filter %/, $(libs-y)))
1123 ifdef CONFIG_MODULES
1124 KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1125 KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1126 else
1127 KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1128 endif
1129 KBUILD_VMLINUX_OBJS += $(patsubst %/,%/built-in.a, $(drivers-y))
1130
1131 export KBUILD_VMLINUX_OBJS KBUILD_VMLINUX_LIBS
1132 export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1133 # used by scripts/Makefile.package
1134 export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) LICENSES arch include scripts tools)
1135
1136 vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
1137
1138 # Recurse until adjust_autoksyms.sh is satisfied
1139 PHONY += autoksyms_recursive
1140 ifdef CONFIG_TRIM_UNUSED_KSYMS
1141 # For the kernel to actually contain only the needed exported symbols,
1142 # we have to build modules as well to determine what those symbols are.
1143 # (this can be evaluated only once include/config/auto.conf has been included)
1144 KBUILD_MODULES := 1
1145
1146 autoksyms_recursive: descend modules.order
1147         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1148           "$(MAKE) -f $(srctree)/Makefile vmlinux"
1149 endif
1150
1151 autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1152
1153 quiet_cmd_autoksyms_h = GEN     $@
1154       cmd_autoksyms_h = mkdir -p $(dir $@); \
1155                         $(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@
1156
1157 $(autoksyms_h):
1158         $(call cmd,autoksyms_h)
1159
1160 ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1161
1162 # Final link of vmlinux with optional arch pass after final link
1163 cmd_link-vmlinux =                                                 \
1164         $(CONFIG_SHELL) $< "$(LD)" "$(KBUILD_LDFLAGS)" "$(LDFLAGS_vmlinux)";    \
1165         $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1166
1167 vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1168         +$(call if_changed_dep,link-vmlinux)
1169
1170 targets := vmlinux
1171
1172 # The actual objects are generated when descending,
1173 # make sure no implicit rule kicks in
1174 $(sort $(vmlinux-deps) $(subdir-modorder)): descend ;
1175
1176 filechk_kernel.release = \
1177         echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1178
1179 # Store (new) KERNELRELEASE string in include/config/kernel.release
1180 include/config/kernel.release: FORCE
1181         $(call filechk,kernel.release)
1182
1183 # Additional helpers built in scripts/
1184 # Carefully list dependencies so we do not try to build scripts twice
1185 # in parallel
1186 PHONY += scripts
1187 scripts: scripts_basic scripts_dtc
1188         $(Q)$(MAKE) $(build)=$(@)
1189
1190 # Things we need to do before we recursively start building the kernel
1191 # or the modules are listed in "prepare".
1192 # A multi level approach is used. prepareN is processed before prepareN-1.
1193 # archprepare is used in arch Makefiles and when processed asm symlink,
1194 # version.h and scripts_basic is processed / created.
1195
1196 PHONY += prepare archprepare
1197
1198 archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1199         asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h \
1200         include/generated/autoconf.h remove-stale-files
1201
1202 prepare0: archprepare
1203         $(Q)$(MAKE) $(build)=scripts/mod
1204         $(Q)$(MAKE) $(build)=.
1205
1206 # All the preparing..
1207 prepare: prepare0
1208
1209 PHONY += remove-stale-files
1210 remove-stale-files:
1211         $(Q)$(srctree)/scripts/remove-stale-files
1212
1213 # Support for using generic headers in asm-generic
1214 asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1215
1216 PHONY += asm-generic uapi-asm-generic
1217 asm-generic: uapi-asm-generic
1218         $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1219         generic=include/asm-generic
1220 uapi-asm-generic:
1221         $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1222         generic=include/uapi/asm-generic
1223
1224 # Generate some files
1225 # ---------------------------------------------------------------------------
1226
1227 # KERNELRELEASE can change from a few different places, meaning version.h
1228 # needs to be updated, so this check is forced on all builds
1229
1230 uts_len := 64
1231 define filechk_utsrelease.h
1232         if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1233           echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1234           exit 1;                                                         \
1235         fi;                                                               \
1236         echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1237 endef
1238
1239 define filechk_version.h
1240         if [ $(SUBLEVEL) -gt 255 ]; then                                 \
1241                 echo \#define LINUX_VERSION_CODE $(shell                 \
1242                 expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1243         else                                                             \
1244                 echo \#define LINUX_VERSION_CODE $(shell                 \
1245                 expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1246         fi;                                                              \
1247         echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
1248         ((c) > 255 ? 255 : (c)))';                                       \
1249         echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
1250         echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
1251         echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1252 endef
1253
1254 $(version_h): PATCHLEVEL := $(if $(PATCHLEVEL), $(PATCHLEVEL), 0)
1255 $(version_h): SUBLEVEL := $(if $(SUBLEVEL), $(SUBLEVEL), 0)
1256 $(version_h): FORCE
1257         $(call filechk,version.h)
1258
1259 include/generated/utsrelease.h: include/config/kernel.release FORCE
1260         $(call filechk,utsrelease.h)
1261
1262 PHONY += headerdep
1263 headerdep:
1264         $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1265         $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1266
1267 # ---------------------------------------------------------------------------
1268 # Kernel headers
1269
1270 #Default location for installed headers
1271 export INSTALL_HDR_PATH = $(objtree)/usr
1272
1273 quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1274       cmd_headers_install = \
1275         mkdir -p $(INSTALL_HDR_PATH); \
1276         rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1277         usr/include $(INSTALL_HDR_PATH)
1278
1279 PHONY += headers_install
1280 headers_install: headers
1281         $(call cmd,headers_install)
1282
1283 PHONY += archheaders archscripts
1284
1285 hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1286
1287 PHONY += headers
1288 headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1289         $(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1290           $(error Headers not exportable for the $(SRCARCH) architecture))
1291         $(Q)$(MAKE) $(hdr-inst)=include/uapi
1292         $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1293
1294 # Deprecated. It is no-op now.
1295 PHONY += headers_check
1296 headers_check:
1297         @echo >&2 "=================== WARNING ==================="
1298         @echo >&2 "Since Linux 5.5, 'make headers_check' is no-op,"
1299         @echo >&2 "and will be removed after Linux 5.15 release."
1300         @echo >&2 "Please remove headers_check from your scripts."
1301         @echo >&2 "==============================================="
1302
1303 ifdef CONFIG_HEADERS_INSTALL
1304 prepare: headers
1305 endif
1306
1307 PHONY += scripts_unifdef
1308 scripts_unifdef: scripts_basic
1309         $(Q)$(MAKE) $(build)=scripts scripts/unifdef
1310
1311 # ---------------------------------------------------------------------------
1312 # Tools
1313
1314 ifdef CONFIG_STACK_VALIDATION
1315 prepare: tools/objtool
1316 endif
1317
1318 ifdef CONFIG_BPF
1319 ifdef CONFIG_DEBUG_INFO_BTF
1320 prepare: tools/bpf/resolve_btfids
1321 endif
1322 endif
1323
1324 PHONY += resolve_btfids_clean
1325
1326 resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1327
1328 # tools/bpf/resolve_btfids directory might not exist
1329 # in output directory, skip its clean in that case
1330 resolve_btfids_clean:
1331 ifneq ($(wildcard $(resolve_btfids_O)),)
1332         $(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1333 endif
1334
1335 # Clear a bunch of variables before executing the submake
1336 ifeq ($(quiet),silent_)
1337 tools_silent=s
1338 endif
1339
1340 tools/: FORCE
1341         $(Q)mkdir -p $(objtree)/tools
1342         $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1343
1344 tools/%: FORCE
1345         $(Q)mkdir -p $(objtree)/tools
1346         $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1347
1348 # ---------------------------------------------------------------------------
1349 # Kernel selftest
1350
1351 PHONY += kselftest
1352 kselftest:
1353         $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1354
1355 kselftest-%: FORCE
1356         $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1357
1358 PHONY += kselftest-merge
1359 kselftest-merge:
1360         $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1361         $(Q)find $(srctree)/tools/testing/selftests -name config | \
1362                 xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1363         $(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1364
1365 # ---------------------------------------------------------------------------
1366 # Devicetree files
1367
1368 ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1369 dtstree := arch/$(SRCARCH)/boot/dts
1370 endif
1371
1372 ifneq ($(dtstree),)
1373
1374 %.dtb: include/config/kernel.release scripts_dtc
1375         $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1376
1377 %.dtbo: include/config/kernel.release scripts_dtc
1378         $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1379
1380 PHONY += dtbs dtbs_install dtbs_check
1381 dtbs: include/config/kernel.release scripts_dtc
1382         $(Q)$(MAKE) $(build)=$(dtstree)
1383
1384 ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1385 export CHECK_DTBS=y
1386 dtbs: dt_binding_check
1387 endif
1388
1389 dtbs_check: dtbs
1390
1391 dtbs_install:
1392         $(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1393
1394 ifdef CONFIG_OF_EARLY_FLATTREE
1395 all: dtbs
1396 endif
1397
1398 endif
1399
1400 PHONY += scripts_dtc
1401 scripts_dtc: scripts_basic
1402         $(Q)$(MAKE) $(build)=scripts/dtc
1403
1404 ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1405 export CHECK_DT_BINDING=y
1406 endif
1407
1408 PHONY += dt_binding_check
1409 dt_binding_check: scripts_dtc
1410         $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1411
1412 # ---------------------------------------------------------------------------
1413 # Modules
1414
1415 ifdef CONFIG_MODULES
1416
1417 # By default, build modules as well
1418
1419 all: modules
1420
1421 # When we're building modules with modversions, we need to consider
1422 # the built-in objects during the descend as well, in order to
1423 # make sure the checksums are up to date before we record them.
1424 ifdef CONFIG_MODVERSIONS
1425   KBUILD_BUILTIN := 1
1426 endif
1427
1428 # Build modules
1429 #
1430 # A module can be listed more than once in obj-m resulting in
1431 # duplicate lines in modules.order files.  Those are removed
1432 # using awk while concatenating to the final file.
1433
1434 PHONY += modules
1435 modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_check modules_prepare
1436
1437 cmd_modules_order = $(AWK) '!x[$$0]++' $(real-prereqs) > $@
1438
1439 modules.order: $(subdir-modorder) FORCE
1440         $(call if_changed,modules_order)
1441
1442 targets += modules.order
1443
1444 # Target to prepare building external modules
1445 PHONY += modules_prepare
1446 modules_prepare: prepare
1447         $(Q)$(MAKE) $(build)=scripts scripts/module.lds
1448
1449 export modules_sign_only :=
1450
1451 ifeq ($(CONFIG_MODULE_SIG),y)
1452 PHONY += modules_sign
1453 modules_sign: modules_install
1454         @:
1455
1456 # modules_sign is a subset of modules_install.
1457 # 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1458 ifeq ($(filter modules_install,$(MAKECMDGOALS)),)
1459 modules_sign_only := y
1460 endif
1461 endif
1462
1463 modinst_pre :=
1464 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
1465 modinst_pre := __modinst_pre
1466 endif
1467
1468 modules_install: $(modinst_pre)
1469 PHONY += __modinst_pre
1470 __modinst_pre:
1471         @rm -rf $(MODLIB)/kernel
1472         @rm -f $(MODLIB)/source
1473         @mkdir -p $(MODLIB)/kernel
1474         @ln -s $(abspath $(srctree)) $(MODLIB)/source
1475         @if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
1476                 rm -f $(MODLIB)/build ; \
1477                 ln -s $(CURDIR) $(MODLIB)/build ; \
1478         fi
1479         @sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order
1480         @cp -f modules.builtin $(MODLIB)/
1481         @cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
1482
1483 endif # CONFIG_MODULES
1484
1485 ###
1486 # Cleaning is done on three levels.
1487 # make clean     Delete most generated files
1488 #                Leave enough to build external modules
1489 # make mrproper  Delete the current configuration, and all generated files
1490 # make distclean Remove editor backup files, patch leftover files and the like
1491
1492 # Directories & files removed with 'make clean'
1493 CLEAN_FILES += include/ksym vmlinux.symvers modules-only.symvers \
1494                modules.builtin modules.builtin.modinfo modules.nsdeps \
1495                compile_commands.json .thinlto-cache
1496
1497 # Directories & files removed with 'make mrproper'
1498 MRPROPER_FILES += include/config include/generated          \
1499                   arch/$(SRCARCH)/include/generated .tmp_objdiff \
1500                   debian snap tar-install \
1501                   .config .config.old .version \
1502                   Module.symvers \
1503                   certs/signing_key.pem certs/signing_key.x509 \
1504                   certs/x509.genkey \
1505                   vmlinux-gdb.py \
1506                   *.spec
1507
1508 # clean - Delete most, but leave enough to build external modules
1509 #
1510 clean: rm-files := $(CLEAN_FILES)
1511
1512 PHONY += archclean vmlinuxclean
1513
1514 vmlinuxclean:
1515         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1516         $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1517
1518 clean: archclean vmlinuxclean resolve_btfids_clean
1519
1520 # mrproper - Delete all generated files, including .config
1521 #
1522 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1523 mrproper-dirs      := $(addprefix _mrproper_,scripts)
1524
1525 PHONY += $(mrproper-dirs) mrproper
1526 $(mrproper-dirs):
1527         $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1528
1529 mrproper: clean $(mrproper-dirs)
1530         $(call cmd,rmfiles)
1531
1532 # distclean
1533 #
1534 PHONY += distclean
1535
1536 distclean: mrproper
1537         @find . $(RCS_FIND_IGNORE) \
1538                 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1539                 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1540                 -o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1541                 -o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1542                 -type f -print | xargs rm -f
1543
1544
1545 # Packaging of the kernel to various formats
1546 # ---------------------------------------------------------------------------
1547
1548 %src-pkg: FORCE
1549         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1550 %pkg: include/config/kernel.release FORCE
1551         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1552
1553 # Brief documentation of the typical targets used
1554 # ---------------------------------------------------------------------------
1555
1556 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1557 boards := $(sort $(notdir $(boards)))
1558 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1559 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1560
1561 PHONY += help
1562 help:
1563         @echo  'Cleaning targets:'
1564         @echo  '  clean           - Remove most generated files but keep the config and'
1565         @echo  '                    enough build support to build external modules'
1566         @echo  '  mrproper        - Remove all generated files + config + various backup files'
1567         @echo  '  distclean       - mrproper + remove editor backup and patch files'
1568         @echo  ''
1569         @echo  'Configuration targets:'
1570         @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1571         @echo  ''
1572         @echo  'Other generic targets:'
1573         @echo  '  all             - Build all targets marked with [*]'
1574         @echo  '* vmlinux         - Build the bare kernel'
1575         @echo  '* modules         - Build all modules'
1576         @echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1577         @echo  '  dir/            - Build all files in dir and below'
1578         @echo  '  dir/file.[ois]  - Build specified target only'
1579         @echo  '  dir/file.ll     - Build the LLVM assembly file'
1580         @echo  '                    (requires compiler support for LLVM assembly generation)'
1581         @echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1582         @echo  '                    (requires a recent binutils and recent build (System.map))'
1583         @echo  '  dir/file.ko     - Build module including final link'
1584         @echo  '  modules_prepare - Set up for building external modules'
1585         @echo  '  tags/TAGS       - Generate tags file for editors'
1586         @echo  '  cscope          - Generate cscope index'
1587         @echo  '  gtags           - Generate GNU GLOBAL index'
1588         @echo  '  kernelrelease   - Output the release version string (use with make -s)'
1589         @echo  '  kernelversion   - Output the version stored in Makefile (use with make -s)'
1590         @echo  '  image_name      - Output the image name (use with make -s)'
1591         @echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1592          echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1593          echo  ''
1594         @echo  'Static analysers:'
1595         @echo  '  checkstack      - Generate a list of stack hogs'
1596         @echo  '  versioncheck    - Sanity check on version.h usage'
1597         @echo  '  includecheck    - Check for duplicate included header files'
1598         @echo  '  export_report   - List the usages of all exported symbols'
1599         @echo  '  headerdep       - Detect inclusion cycles in headers'
1600         @echo  '  coccicheck      - Check with Coccinelle'
1601         @echo  '  clang-analyzer  - Check with clang static analyzer'
1602         @echo  '  clang-tidy      - Check with clang-tidy'
1603         @echo  ''
1604         @echo  'Tools:'
1605         @echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1606         @echo  ''
1607         @echo  'Kernel selftest:'
1608         @echo  '  kselftest         - Build and run kernel selftest'
1609         @echo  '                      Build, install, and boot kernel before'
1610         @echo  '                      running kselftest on it'
1611         @echo  '                      Run as root for full coverage'
1612         @echo  '  kselftest-all     - Build kernel selftest'
1613         @echo  '  kselftest-install - Build and install kernel selftest'
1614         @echo  '  kselftest-clean   - Remove all generated kselftest files'
1615         @echo  '  kselftest-merge   - Merge all the config dependencies of'
1616         @echo  '                      kselftest to existing .config.'
1617         @echo  ''
1618         @$(if $(dtstree), \
1619                 echo 'Devicetree:'; \
1620                 echo '* dtbs             - Build device tree blobs for enabled boards'; \
1621                 echo '  dtbs_install     - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1622                 echo '  dt_binding_check - Validate device tree binding documents'; \
1623                 echo '  dtbs_check       - Validate device tree source files';\
1624                 echo '')
1625
1626         @echo 'Userspace tools targets:'
1627         @echo '  use "make tools/help"'
1628         @echo '  or  "cd tools; make help"'
1629         @echo  ''
1630         @echo  'Kernel packaging:'
1631         @$(MAKE) -f $(srctree)/scripts/Makefile.package help
1632         @echo  ''
1633         @echo  'Documentation targets:'
1634         @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1635         @echo  ''
1636         @echo  'Architecture specific targets ($(SRCARCH)):'
1637         @$(if $(archhelp),$(archhelp),\
1638                 echo '  No architecture specific help defined for $(SRCARCH)')
1639         @echo  ''
1640         @$(if $(boards), \
1641                 $(foreach b, $(boards), \
1642                 printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1643                 echo '')
1644         @$(if $(board-dirs), \
1645                 $(foreach b, $(board-dirs), \
1646                 printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1647                 printf "  %-16s - Show all of the above\\n" help-boards; \
1648                 echo '')
1649
1650         @echo  '  make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1651         @echo  '  make V=2   [targets] 2 => give reason for rebuild of target'
1652         @echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1653         @echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1654         @echo  '                       (sparse by default)'
1655         @echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1656         @echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1657         @echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
1658         @echo  '                1: warnings which may be relevant and do not occur too often'
1659         @echo  '                2: warnings which occur quite often but may still be relevant'
1660         @echo  '                3: more obscure warnings, can most likely be ignored'
1661         @echo  '                Multiple levels can be combined with W=12 or W=123'
1662         @echo  ''
1663         @echo  'Execute "make" or "make all" to build all targets marked with [*] '
1664         @echo  'For further info see the ./README file'
1665
1666
1667 help-board-dirs := $(addprefix help-,$(board-dirs))
1668
1669 help-boards: $(help-board-dirs)
1670
1671 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1672
1673 $(help-board-dirs): help-%:
1674         @echo  'Architecture specific targets ($(SRCARCH) $*):'
1675         @$(if $(boards-per-dir), \
1676                 $(foreach b, $(boards-per-dir), \
1677                 printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1678                 echo '')
1679
1680
1681 # Documentation targets
1682 # ---------------------------------------------------------------------------
1683 DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1684                linkcheckdocs dochelp refcheckdocs
1685 PHONY += $(DOC_TARGETS)
1686 $(DOC_TARGETS):
1687         $(Q)$(MAKE) $(build)=Documentation $@
1688
1689 # Misc
1690 # ---------------------------------------------------------------------------
1691
1692 PHONY += scripts_gdb
1693 scripts_gdb: prepare0
1694         $(Q)$(MAKE) $(build)=scripts/gdb
1695         $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1696
1697 ifdef CONFIG_GDB_SCRIPTS
1698 all: scripts_gdb
1699 endif
1700
1701 else # KBUILD_EXTMOD
1702
1703 ###
1704 # External module support.
1705 # When building external modules the kernel used as basis is considered
1706 # read-only, and no consistency checks are made and the make
1707 # system is not used on the basis kernel. If updates are required
1708 # in the basis kernel ordinary make commands (without M=...) must be used.
1709
1710 # We are always building only modules.
1711 KBUILD_BUILTIN :=
1712 KBUILD_MODULES := 1
1713
1714 build-dirs := $(KBUILD_EXTMOD)
1715 $(MODORDER): descend
1716         @:
1717
1718 compile_commands.json: $(extmod_prefix)compile_commands.json
1719 PHONY += compile_commands.json
1720
1721 clean-dirs := $(KBUILD_EXTMOD)
1722 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1723         $(KBUILD_EXTMOD)/compile_commands.json $(KBUILD_EXTMOD)/.thinlto-cache
1724
1725 PHONY += help
1726 help:
1727         @echo  '  Building external modules.'
1728         @echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1729         @echo  ''
1730         @echo  '  modules         - default target, build the module(s)'
1731         @echo  '  modules_install - install the module'
1732         @echo  '  clean           - remove generated files in module directory only'
1733         @echo  ''
1734
1735 # no-op for external module builds
1736 PHONY += prepare modules_prepare
1737
1738 endif # KBUILD_EXTMOD
1739
1740 # ---------------------------------------------------------------------------
1741 # Modules
1742
1743 PHONY += modules modules_install
1744
1745 ifdef CONFIG_MODULES
1746
1747 modules: modules_check
1748         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1749
1750 PHONY += modules_check
1751 modules_check: $(MODORDER)
1752         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1753
1754 quiet_cmd_depmod = DEPMOD  $(MODLIB)
1755       cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1756                    $(KERNELRELEASE)
1757
1758 modules_install:
1759         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1760         $(call cmd,depmod)
1761
1762 else # CONFIG_MODULES
1763
1764 # Modules not configured
1765 # ---------------------------------------------------------------------------
1766
1767 modules modules_install:
1768         @echo >&2 '***'
1769         @echo >&2 '*** The present kernel configuration has modules disabled.'
1770         @echo >&2 '*** To use the module feature, please run "make menuconfig" etc.'
1771         @echo >&2 '*** to enable CONFIG_MODULES.'
1772         @echo >&2 '***'
1773         @exit 1
1774
1775 endif # CONFIG_MODULES
1776
1777 # Single targets
1778 # ---------------------------------------------------------------------------
1779 # To build individual files in subdirectories, you can do like this:
1780 #
1781 #   make foo/bar/baz.s
1782 #
1783 # The supported suffixes for single-target are listed in 'single-targets'
1784 #
1785 # To build only under specific subdirectories, you can do like this:
1786 #
1787 #   make foo/bar/baz/
1788
1789 ifdef single-build
1790
1791 # .ko is special because modpost is needed
1792 single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1793 single-no-ko := $(sort $(patsubst %.ko,%.mod, $(MAKECMDGOALS)))
1794
1795 $(single-ko): single_modpost
1796         @:
1797 $(single-no-ko): descend
1798         @:
1799
1800 ifeq ($(KBUILD_EXTMOD),)
1801 # For the single build of in-tree modules, use a temporary file to avoid
1802 # the situation of modules_install installing an invalid modules.order.
1803 MODORDER := .modules.tmp
1804 endif
1805
1806 PHONY += single_modpost
1807 single_modpost: $(single-no-ko) modules_prepare
1808         $(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$m;) } > $(MODORDER)
1809         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1810
1811 KBUILD_MODULES := 1
1812
1813 export KBUILD_SINGLE_TARGETS := $(addprefix $(extmod_prefix), $(single-no-ko))
1814
1815 # trim unrelated directories
1816 build-dirs := $(foreach d, $(build-dirs), \
1817                         $(if $(filter $(d)/%, $(KBUILD_SINGLE_TARGETS)), $(d)))
1818
1819 endif
1820
1821 ifndef CONFIG_MODULES
1822 KBUILD_MODULES :=
1823 endif
1824
1825 # Handle descending into subdirectories listed in $(build-dirs)
1826 # Preset locale variables to speed up the build process. Limit locale
1827 # tweaks to this spot to avoid wrong language settings when running
1828 # make menuconfig etc.
1829 # Error messages still appears in the original language
1830 PHONY += descend $(build-dirs)
1831 descend: $(build-dirs)
1832 $(build-dirs): prepare
1833         $(Q)$(MAKE) $(build)=$@ \
1834         single-build=$(if $(filter-out $@/, $(filter $@/%, $(KBUILD_SINGLE_TARGETS))),1) \
1835         need-builtin=1 need-modorder=1
1836
1837 clean-dirs := $(addprefix _clean_, $(clean-dirs))
1838 PHONY += $(clean-dirs) clean
1839 $(clean-dirs):
1840         $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1841
1842 clean: $(clean-dirs)
1843         $(call cmd,rmfiles)
1844         @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1845                 \( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1846                 -o -name '*.ko.*' \
1847                 -o -name '*.dtb' -o -name '*.dtbo' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1848                 -o -name '*.dwo' -o -name '*.lst' \
1849                 -o -name '*.su' -o -name '*.mod' \
1850                 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1851                 -o -name '*.lex.c' -o -name '*.tab.[ch]' \
1852                 -o -name '*.asn1.[ch]' \
1853                 -o -name '*.symtypes' -o -name 'modules.order' \
1854                 -o -name '.tmp_*.o.*' \
1855                 -o -name '*.c.[012]*.*' \
1856                 -o -name '*.ll' \
1857                 -o -name '*.gcno' \
1858                 -o -name '*.*.symversions' \) -type f -print | xargs rm -f
1859
1860 # Generate tags for editors
1861 # ---------------------------------------------------------------------------
1862 quiet_cmd_tags = GEN     $@
1863       cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1864
1865 tags TAGS cscope gtags: FORCE
1866         $(call cmd,tags)
1867
1868 # Script to generate missing namespace dependencies
1869 # ---------------------------------------------------------------------------
1870
1871 PHONY += nsdeps
1872 nsdeps: export KBUILD_NSDEPS=1
1873 nsdeps: modules
1874         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1875
1876 # Clang Tooling
1877 # ---------------------------------------------------------------------------
1878
1879 quiet_cmd_gen_compile_commands = GEN     $@
1880       cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
1881
1882 $(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
1883         $(if $(KBUILD_EXTMOD),,$(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)) \
1884         $(if $(CONFIG_MODULES), $(MODORDER)) FORCE
1885         $(call if_changed,gen_compile_commands)
1886
1887 targets += $(extmod_prefix)compile_commands.json
1888
1889 PHONY += clang-tidy clang-analyzer
1890
1891 ifdef CONFIG_CC_IS_CLANG
1892 quiet_cmd_clang_tools = CHECK   $<
1893       cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
1894
1895 clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
1896         $(call cmd,clang_tools)
1897 else
1898 clang-tidy clang-analyzer:
1899         @echo "$@ requires CC=clang" >&2
1900         @false
1901 endif
1902
1903 # Scripts to check various things for consistency
1904 # ---------------------------------------------------------------------------
1905
1906 PHONY += includecheck versioncheck coccicheck export_report
1907
1908 includecheck:
1909         find $(srctree)/* $(RCS_FIND_IGNORE) \
1910                 -name '*.[hcS]' -type f -print | sort \
1911                 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1912
1913 versioncheck:
1914         find $(srctree)/* $(RCS_FIND_IGNORE) \
1915                 -name '*.[hcS]' -type f -print | sort \
1916                 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1917
1918 coccicheck:
1919         $(Q)$(BASH) $(srctree)/scripts/$@
1920
1921 export_report:
1922         $(PERL) $(srctree)/scripts/export_report.pl
1923
1924 PHONY += checkstack kernelrelease kernelversion image_name
1925
1926 # UML needs a little special treatment here.  It wants to use the host
1927 # toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
1928 # else wants $(ARCH), including people doing cross-builds, which means
1929 # that $(SUBARCH) doesn't work here.
1930 ifeq ($(ARCH), um)
1931 CHECKSTACK_ARCH := $(SUBARCH)
1932 else
1933 CHECKSTACK_ARCH := $(ARCH)
1934 endif
1935 checkstack:
1936         $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1937         $(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1938
1939 kernelrelease:
1940         @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1941
1942 kernelversion:
1943         @echo $(KERNELVERSION)
1944
1945 image_name:
1946         @echo $(KBUILD_IMAGE)
1947
1948 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
1949       cmd_rmfiles = rm -rf $(rm-files)
1950
1951 # read saved command lines for existing targets
1952 existing-targets := $(wildcard $(sort $(targets)))
1953
1954 -include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
1955
1956 endif # config-build
1957 endif # mixed-build
1958 endif # need-sub-make
1959
1960 PHONY += FORCE
1961 FORCE:
1962
1963 # Declare the contents of the PHONY variable as phony.  We keep that
1964 # information in a variable so we can use it in if_changed and friends.
1965 .PHONY: $(PHONY)