Makefile

   1 # SPDX-License-Identifier: GPL-2.0
   2 VERSION = 5
   3 PATCHLEVEL = 9
   4 SUBLEVEL = 0
   5 EXTRAVERSION = -rc6
   6 NAME = 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         $(error targets prefixed with '__' are only for internal use))
  16
  17 # That's our default target when none is given on the command line
  18 PHONY := __all
  19 __all:
  20
  21 # We are using a recursive build, so we need to do a little thinking
  22 # to get the ordering right.
  23 #
  24 # Most importantly: sub-Makefiles should only ever modify files in
  25 # their own directory. If in some directory we have a dependency on
  26 # a file in another dir (which doesn't happen often, but it's often
  27 # unavoidable when linking the built-in.a targets which finally
  28 # turn into vmlinux), we will call a sub make in that other dir, and
  29 # after that we are sure that everything which is in that other dir
  30 # is now up to date.
  31 #
  32 # The only cases where we need to modify files which have global
  33 # effects are thus separated out and done before the recursive
  34 # descending is started. They are now explicitly listed as the
  35 # prepare rule.
  36
  37 ifneq ($(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 --%,$(MAKEFLAGS))),)
  98   quiet=silent_
  99 endif
 100
 101 export quiet Q KBUILD_VERBOSE
 102
 103 # Kbuild will save output files in the current working directory.
 104 # This does not need to match to the root of the kernel source tree.
 105 #
 106 # For example, you can do this:
 107 #
 108 #  cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
 109 #
 110 # If you want to save output files in a different location, there are
 111 # two syntaxes to specify it.
 112 #
 113 # 1) O=
 114 # Use "make O=dir/to/store/output/files/"
 115 #
 116 # 2) Set KBUILD_OUTPUT
 117 # Set the environment variable KBUILD_OUTPUT to point to the output directory.
 118 # export KBUILD_OUTPUT=dir/to/store/output/files/; make
 119 #
 120 # The O= assignment takes precedence over the KBUILD_OUTPUT environment
 121 # variable.
 122
 123 # Do we want to change the working directory?
 124 ifeq ("$(origin O)", "command line")
 125   KBUILD_OUTPUT := $(O)
 126 endif
 127
 128 ifneq ($(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.
 131 abs_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
 136 abs_objtree := $(realpath $(abs_objtree))
 137 else
 138 abs_objtree := $(CURDIR)
 139 endif # ifneq ($(KBUILD_OUTPUT),)
 140
 141 ifeq ($(abs_objtree),$(CURDIR))
 142 # Suppress "Entering directory ..." unless we are changing the work directory.
 143 MAKEFLAGS += --no-print-directory
 144 else
 145 need-sub-make := 1
 146 endif
 147
 148 abs_srctree := $(realpath $(dir $(lastword $(MAKEFILE_LIST))))
 149
 150 ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
 151 $(error source directory cannot contain spaces or colons)
 152 endif
 153
 154 ifneq ($(abs_srctree),$(abs_objtree))
 155 # Look for make include files relative to root of kernel src
 156 #
 157 # This does not become effective immediately because MAKEFLAGS is re-parsed
 158 # once after the Makefile is read. We need to invoke sub-make.
 159 MAKEFLAGS += --include-dir=$(abs_srctree)
 160 need-sub-make := 1
 161 endif
 162
 163 this-makefile := $(lastword $(MAKEFILE_LIST))
 164
 165 ifneq ($(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.
 168 need-sub-make := 1
 169 # Cancel implicit rules for this Makefile.
 170 $(this-makefile): ;
 171 endif
 172
 173 export abs_srctree abs_objtree
 174 export sub_make_done := 1
 175
 176 ifeq ($(need-sub-make),1)
 177
 178 PHONY += $(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 $(MAKECMDGOALS)
 186
 187 endif # need-sub-make
 188 endif # sub_make_done
 189
 190 # We process the rest of the Makefile if this is the final invocation of make
 191 ifeq ($(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.
 196 MAKEFLAGS += --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
 208 ifeq ("$(origin C)", "command line")
 209   KBUILD_CHECKSRC = $(C)
 210 endif
 211 ifndef KBUILD_CHECKSRC
 212   KBUILD_CHECKSRC = 0
 213 endif
 214
 215 # Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
 216 # directory of external module to build. Setting M= takes precedence.
 217 ifeq ("$(origin M)", "command line")
 218   KBUILD_EXTMOD := $(M)
 219 endif
 220
 221 $(if $(word 2, $(KBUILD_EXTMOD)), \
 222         $(error building multiple external modules is not supported))
 223
 224 export KBUILD_CHECKSRC KBUILD_EXTMOD
 225
 226 extmod-prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
 227
 228 ifeq ($(abs_srctree),$(abs_objtree))
 229         # building in the source tree
 230         srctree := .
 231         building_out_of_srctree :=
 232 else
 233         ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
 234                 # building in a subdirectory of the source tree
 235                 srctree := ..
 236         else
 237                 srctree := $(abs_srctree)
 238         endif
 239         building_out_of_srctree := 1
 240 endif
 241
 242 ifneq ($(KBUILD_ABS_SRCTREE),)
 243 srctree := $(abs_srctree)
 244 endif
 245
 246 objtree         := .
 247 VPATH           := $(srctree)
 248
 249 export 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
 259 version_h := include/generated/uapi/linux/version.h
 260 old_version_h := include/linux/version.h
 261
 262 clean-targets := %clean mrproper cleandocs
 263 no-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
 268 no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease
 269 single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
 270
 271 config-build    :=
 272 mixed-build     :=
 273 need-config     := 1
 274 may-sync-config := 1
 275 single-build    :=
 276
 277 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
 278         ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
 279                 need-config :=
 280         endif
 281 endif
 282
 283 ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
 284         ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
 285                 may-sync-config :=
 286         endif
 287 endif
 288
 289 ifneq ($(KBUILD_EXTMOD),)
 290         may-sync-config :=
 291 endif
 292
 293 ifeq ($(KBUILD_EXTMOD),)
 294         ifneq ($(filter %config,$(MAKECMDGOALS)),)
 295                 config-build := 1
 296                 ifneq ($(words $(MAKECMDGOALS)),1)
 297                         mixed-build := 1
 298                 endif
 299         endif
 300 endif
 301
 302 # We cannot build single targets and the others at the same time
 303 ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
 304         single-build := 1
 305         ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
 306                 mixed-build := 1
 307         endif
 308 endif
 309
 310 # For "make -j clean all", "make -j mrproper defconfig all", etc.
 311 ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
 312         ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
 313                 mixed-build := 1
 314         endif
 315 endif
 316
 317 # install and modules_install need also be processed one by one
 318 ifneq ($(filter install,$(MAKECMDGOALS)),)
 319         ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
 320                 mixed-build := 1
 321         endif
 322 endif
 323
 324 ifdef mixed-build
 325 # ===========================================================================
 326 # We're called with mixed targets (*config and build targets).
 327 # Handle them one by one.
 328
 329 PHONY += $(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
 340 else # !mixed-build
 341
 342 include scripts/Kbuild.include
 343
 344 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
 345 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
 346 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
 347 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
 348
 349 include 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
 369 ARCH            ?= $(SUBARCH)
 370
 371 # Architecture as present in compile.h
 372 UTS_MACHINE     := $(ARCH)
 373 SRCARCH         := $(ARCH)
 374
 375 # Additional ARCH settings for x86
 376 ifeq ($(ARCH),i386)
 377         SRCARCH := x86
 378 endif
 379 ifeq ($(ARCH),x86_64)
 380         SRCARCH := x86
 381 endif
 382
 383 # Additional ARCH settings for sparc
 384 ifeq ($(ARCH),sparc32)
 385        SRCARCH := sparc
 386 endif
 387 ifeq ($(ARCH),sparc64)
 388        SRCARCH := sparc
 389 endif
 390
 391 # Additional ARCH settings for sh
 392 ifeq ($(ARCH),sh64)
 393        SRCARCH := sh
 394 endif
 395
 396 KCONFIG_CONFIG  ?= .config
 397 export KCONFIG_CONFIG
 398
 399 # Default file for 'make defconfig'. This may be overridden by arch-Makefile.
 400 export KBUILD_DEFCONFIG := defconfig
 401
 402 # SHELL used by kbuild
 403 CONFIG_SHELL := sh
 404
 405 HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
 406 HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
 407 HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
 408
 409 ifneq ($(LLVM),)
 410 HOSTCC  = clang
 411 HOSTCXX = clang++
 412 else
 413 HOSTCC  = gcc
 414 HOSTCXX = g++
 415 endif
 416
 417 export KBUILD_USERCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
 418                               -O2 -fomit-frame-pointer -std=gnu89
 419 export KBUILD_USERLDFLAGS :=
 420
 421 KBUILD_HOSTCFLAGS   := $(KBUILD_USERCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
 422 KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
 423 KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
 424 KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
 425
 426 # Make variables (CC, etc...)
 427 CPP             = $(CC) -E
 428 ifneq ($(LLVM),)
 429 CC              = clang
 430 LD              = ld.lld
 431 AR              = llvm-ar
 432 NM              = llvm-nm
 433 OBJCOPY         = llvm-objcopy
 434 OBJDUMP         = llvm-objdump
 435 READELF         = llvm-readelf
 436 OBJSIZE         = llvm-size
 437 STRIP           = llvm-strip
 438 else
 439 CC              = $(CROSS_COMPILE)gcc
 440 LD              = $(CROSS_COMPILE)ld
 441 AR              = $(CROSS_COMPILE)ar
 442 NM              = $(CROSS_COMPILE)nm
 443 OBJCOPY         = $(CROSS_COMPILE)objcopy
 444 OBJDUMP         = $(CROSS_COMPILE)objdump
 445 READELF         = $(CROSS_COMPILE)readelf
 446 OBJSIZE         = $(CROSS_COMPILE)size
 447 STRIP           = $(CROSS_COMPILE)strip
 448 endif
 449 PAHOLE          = pahole
 450 RESOLVE_BTFIDS  = $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
 451 LEX             = flex
 452 YACC            = bison
 453 AWK             = awk
 454 INSTALLKERNEL  := installkernel
 455 DEPMOD          = /sbin/depmod
 456 PERL            = perl
 457 PYTHON          = python
 458 PYTHON3         = python3
 459 CHECK           = sparse
 460 BASH            = bash
 461 KGZIP           = gzip
 462 KBZIP2          = bzip2
 463 KLZOP           = lzop
 464 LZMA            = lzma
 465 LZ4             = lz4c
 466 XZ              = xz
 467 ZSTD            = zstd
 468
 469 CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
 470                   -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
 471 NOSTDINC_FLAGS :=
 472 CFLAGS_MODULE   =
 473 AFLAGS_MODULE   =
 474 LDFLAGS_MODULE  =
 475 CFLAGS_KERNEL   =
 476 AFLAGS_KERNEL   =
 477 LDFLAGS_vmlinux =
 478
 479 # Use USERINCLUDE when you must reference the UAPI directories only.
 480 USERINCLUDE    := \
 481                 -I$(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 $(srctree)/include/linux/kconfig.h
 486
 487 # Use LINUXINCLUDE when you must reference the include/ directory.
 488 # Needed to be compatible with the O= option
 489 LINUXINCLUDE    := \
 490                 -I$(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
 496 KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
 497 KBUILD_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
 502 KBUILD_CPPFLAGS := -D__KERNEL__
 503 KBUILD_AFLAGS_KERNEL :=
 504 KBUILD_CFLAGS_KERNEL :=
 505 KBUILD_AFLAGS_MODULE  := -DMODULE
 506 KBUILD_CFLAGS_MODULE  := -DMODULE
 507 KBUILD_LDFLAGS_MODULE :=
 508 export KBUILD_LDS_MODULE := $(srctree)/scripts/module-common.lds
 509 KBUILD_LDFLAGS :=
 510 CLANG_FLAGS :=
 511
 512 export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC
 513 export CPP AR NM STRIP OBJCOPY OBJDUMP OBJSIZE READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
 514 export PERL PYTHON PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
 515 export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
 516 export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
 517
 518 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
 519 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
 520 export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN CFLAGS_KCSAN
 521 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
 522 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
 523 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
 524
 525 # Files to ignore in find ... statements
 526
 527 export 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
 530 export 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/
 537 PHONY += scripts_basic
 538 scripts_basic:
 539         $(Q)$(MAKE) $(build)=scripts/basic
 540         $(Q)rm -f .tmp_quiet_recordmcount
 541
 542 PHONY += 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
 549 outputmakefile:
 550 ifdef 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         $(Q)test -e .gitignore || \
 563         { echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
 564 endif
 565
 566 ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),)
 567 ifneq ($(CROSS_COMPILE),)
 568 CLANG_FLAGS     += --target=$(notdir $(CROSS_COMPILE:%-=%))
 569 GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
 570 CLANG_FLAGS     += --prefix=$(GCC_TOOLCHAIN_DIR)$(notdir $(CROSS_COMPILE))
 571 GCC_TOOLCHAIN   := $(realpath $(GCC_TOOLCHAIN_DIR)/..)
 572 endif
 573 ifneq ($(GCC_TOOLCHAIN),)
 574 CLANG_FLAGS     += --gcc-toolchain=$(GCC_TOOLCHAIN)
 575 endif
 576 ifneq ($(LLVM_IAS),1)
 577 CLANG_FLAGS     += -no-integrated-as
 578 endif
 579 CLANG_FLAGS     += -Werror=unknown-warning-option
 580 KBUILD_CFLAGS   += $(CLANG_FLAGS)
 581 KBUILD_AFLAGS   += $(CLANG_FLAGS)
 582 export CLANG_FLAGS
 583 endif
 584
 585 # The expansion should be delayed until arch/$(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.
 589 CC_VERSION_TEXT = $(shell $(CC) --version 2>/dev/null | head -n 1)
 590
 591 ifdef config-build
 592 # ===========================================================================
 593 # *config targets only - make sure prerequisites are updated, and descend
 594 # in scripts/kconfig to make the *config target
 595
 596 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
 597 # KBUILD_DEFCONFIG may point out an alternative default configuration
 598 # used for 'make defconfig'
 599 include arch/$(SRCARCH)/Makefile
 600 export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
 601
 602 config: outputmakefile scripts_basic FORCE
 603         $(Q)$(MAKE) $(build)=scripts/kconfig $@
 604
 605 %config: outputmakefile scripts_basic FORCE
 606         $(Q)$(MAKE) $(build)=scripts/kconfig $@
 607
 608 else #!config-build
 609 # ===========================================================================
 610 # Build targets only - this includes vmlinux, arch specific targets, clean
 611 # targets and others. In general all targets except *config targets.
 612
 613 # If building an external module we do not care about the all: rule
 614 # but instead __all depend on modules
 615 PHONY += all
 616 ifeq ($(KBUILD_EXTMOD),)
 617 __all: all
 618 else
 619 __all: modules
 620 endif
 621
 622 # Decide whether to build built-in, modular, or both.
 623 # Normally, just do built-in.
 624
 625 KBUILD_MODULES :=
 626 KBUILD_BUILTIN := 1
 627
 628 # If we have only "make modules", don't compile built-in objects.
 629 ifeq ($(MAKECMDGOALS),modules)
 630   KBUILD_BUILTIN :=
 631 endif
 632
 633 # If we have "make <whatever> modules", compile modules
 634 # in addition to whatever we do anyway.
 635 # Just "make" or "make all" shall build modules as well
 636
 637 ifneq ($(filter all modules nsdeps,$(MAKECMDGOALS)),)
 638   KBUILD_MODULES := 1
 639 endif
 640
 641 ifeq ($(MAKECMDGOALS),)
 642   KBUILD_MODULES := 1
 643 endif
 644
 645 export KBUILD_MODULES KBUILD_BUILTIN
 646
 647 ifdef need-config
 648 include include/config/auto.conf
 649 endif
 650
 651 ifeq ($(KBUILD_EXTMOD),)
 652 # Objects we will link into vmlinux / subdirs we need to visit
 653 core-y          := init/ usr/
 654 drivers-y       := drivers/ sound/
 655 drivers-$(CONFIG_SAMPLES) += samples/
 656 drivers-y       += net/ virt/
 657 libs-y          := lib/
 658 endif # 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
 664 all: vmlinux
 665
 666 CFLAGS_GCOV     := -fprofile-arcs -ftest-coverage \
 667         $(call cc-option,-fno-tree-loop-im) \
 668         $(call cc-disable-warning,maybe-uninitialized,)
 669 export CFLAGS_GCOV
 670
 671 # The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
 672 ifdef CONFIG_FUNCTION_TRACER
 673   CC_FLAGS_FTRACE := -pg
 674 endif
 675
 676 RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
 677 RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
 678 RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
 679 RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
 680 RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
 681 RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
 682 export RETPOLINE_CFLAGS
 683 export RETPOLINE_VDSO_CFLAGS
 684
 685 include arch/$(SRCARCH)/Makefile
 686
 687 ifdef need-config
 688 ifdef may-sync-config
 689 # Read in dependencies to all Kconfig* files, make sure to run syncconfig if
 690 # changes are detected. This should be included after arch/$(SRCARCH)/Makefile
 691 # because some architectures define CROSS_COMPILE there.
 692 include 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
 712 else # !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
 716 PHONY += include/config/auto.conf
 717
 718 include/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
 727 endif # may-sync-config
 728 endif # need-config
 729
 730 KBUILD_CFLAGS   += $(call cc-option,-fno-delete-null-pointer-checks,)
 731 KBUILD_CFLAGS   += $(call cc-disable-warning,frame-address,)
 732 KBUILD_CFLAGS   += $(call cc-disable-warning, format-truncation)
 733 KBUILD_CFLAGS   += $(call cc-disable-warning, format-overflow)
 734 KBUILD_CFLAGS   += $(call cc-disable-warning, address-of-packed-member)
 735
 736 ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
 737 KBUILD_CFLAGS += -O2
 738 else ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3
 739 KBUILD_CFLAGS += -O3
 740 else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
 741 KBUILD_CFLAGS += -Os
 742 endif
 743
 744 # Tell gcc to never replace conditional load with a non-conditional one
 745 KBUILD_CFLAGS   += $(call cc-option,--param=allow-store-data-races=0)
 746 KBUILD_CFLAGS   += $(call cc-option,-fno-allow-store-data-races)
 747
 748 ifdef 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
 753 KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
 754                  $(call cc-option,-fno-ipa-cp-clone,) \
 755                  $(call cc-option,-fno-partial-inlining)
 756 endif
 757
 758 ifneq ($(CONFIG_FRAME_WARN),0)
 759 KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
 760 endif
 761
 762 stackp-flags-y                                    := -fno-stack-protector
 763 stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
 764 stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
 765
 766 KBUILD_CFLAGS += $(stackp-flags-y)
 767
 768 ifdef CONFIG_CC_IS_CLANG
 769 KBUILD_CPPFLAGS += -Qunused-arguments
 770 KBUILD_CFLAGS += -Wno-format-invalid-specifier
 771 KBUILD_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
 775 KBUILD_CFLAGS += -mno-global-merge
 776 else
 777
 778 # These warnings generated too much noise in a regular build.
 779 # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
 780 KBUILD_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.
 785 KBUILD_CFLAGS += $(call cc-option,-Wimplicit-fallthrough,)
 786 endif
 787
 788 KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
 789 ifdef CONFIG_FRAME_POINTER
 790 KBUILD_CFLAGS   += -fno-omit-frame-pointer -fno-optimize-sibling-calls
 791 else
 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.
 797 ifndef CONFIG_FUNCTION_TRACER
 798 KBUILD_CFLAGS   += -fomit-frame-pointer
 799 endif
 800 endif
 801
 802 # Initialize all stack variables with a 0xAA pattern.
 803 ifdef CONFIG_INIT_STACK_ALL_PATTERN
 804 KBUILD_CFLAGS   += -ftrivial-auto-var-init=pattern
 805 endif
 806
 807 # Initialize all stack variables with a zero value.
 808 ifdef 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.
 812 KBUILD_CFLAGS   += -ftrivial-auto-var-init=zero
 813 KBUILD_CFLAGS   += -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
 814 endif
 815
 816 DEBUG_CFLAGS    := $(call cc-option, -fno-var-tracking-assignments)
 817
 818 ifdef CONFIG_DEBUG_INFO
 819 ifdef CONFIG_DEBUG_INFO_SPLIT
 820 DEBUG_CFLAGS    += -gsplit-dwarf
 821 else
 822 DEBUG_CFLAGS    += -g
 823 endif
 824 KBUILD_AFLAGS   += -Wa,-gdwarf-2
 825 endif
 826 ifdef CONFIG_DEBUG_INFO_DWARF4
 827 DEBUG_CFLAGS    += -gdwarf-4
 828 endif
 829
 830 ifdef CONFIG_DEBUG_INFO_REDUCED
 831 DEBUG_CFLAGS    += $(call cc-option, -femit-struct-debug-baseonly) \
 832                    $(call cc-option,-fno-var-tracking)
 833 endif
 834
 835 ifdef CONFIG_DEBUG_INFO_COMPRESSED
 836 DEBUG_CFLAGS    += -gz=zlib
 837 KBUILD_AFLAGS   += -gz=zlib
 838 KBUILD_LDFLAGS  += --compress-debug-sections=zlib
 839 endif
 840
 841 KBUILD_CFLAGS += $(DEBUG_CFLAGS)
 842 export DEBUG_CFLAGS
 843
 844 ifdef CONFIG_FUNCTION_TRACER
 845 ifdef CONFIG_FTRACE_MCOUNT_RECORD
 846   # gcc 5 supports generating the mcount tables directly
 847   ifeq ($(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 ($(call cc-option-yn, -mnop-mcount),y)
 853       CC_FLAGS_FTRACE   += -mnop-mcount
 854       CC_FLAGS_USING    += -DCC_USING_NOP_MCOUNT
 855     endif
 856   endif
 857 endif
 858 ifdef CONFIG_HAVE_FENTRY
 859   ifeq ($(call cc-option-yn, -mfentry),y)
 860     CC_FLAGS_FTRACE     += -mfentry
 861     CC_FLAGS_USING      += -DCC_USING_FENTRY
 862   endif
 863 endif
 864 export CC_FLAGS_FTRACE
 865 KBUILD_CFLAGS   += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
 866 KBUILD_AFLAGS   += $(CC_FLAGS_USING)
 867 ifdef CONFIG_DYNAMIC_FTRACE
 868         ifdef CONFIG_HAVE_C_RECORDMCOUNT
 869                 BUILD_C_RECORDMCOUNT := y
 870                 export BUILD_C_RECORDMCOUNT
 871         endif
 872 endif
 873 endif
 874
 875 # We trigger additional mismatches with less inlining
 876 ifdef CONFIG_DEBUG_SECTION_MISMATCH
 877 KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
 878 endif
 879
 880 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
 881 KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
 882 LDFLAGS_vmlinux += --gc-sections
 883 endif
 884
 885 ifdef CONFIG_SHADOW_CALL_STACK
 886 CC_FLAGS_SCS    := -fsanitize=shadow-call-stack
 887 KBUILD_CFLAGS   += $(CC_FLAGS_SCS)
 888 export CC_FLAGS_SCS
 889 endif
 890
 891 ifdef CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_32B
 892 KBUILD_CFLAGS += -falign-functions=32
 893 endif
 894
 895 # arch Makefile may override CC so keep this after arch Makefile is included
 896 NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
 897
 898 # warn about C99 declaration after statement
 899 KBUILD_CFLAGS += -Wdeclaration-after-statement
 900
 901 # Variable Length Arrays (VLAs) should not be used anywhere in the kernel
 902 KBUILD_CFLAGS += -Wvla
 903
 904 # disable pointer signed / unsigned warnings in gcc 4.0
 905 KBUILD_CFLAGS += -Wno-pointer-sign
 906
 907 # disable stringop warnings in gcc 8+
 908 KBUILD_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
 911 KBUILD_CFLAGS += $(call cc-disable-warning, zero-length-bounds)
 912 KBUILD_CFLAGS += $(call cc-disable-warning, array-bounds)
 913 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
 914
 915 # Another good warning that we'll want to enable eventually
 916 KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
 917
 918 # Enabled with W=2, disabled by default as noisy
 919 KBUILD_CFLAGS += $(call cc-disable-warning, maybe-uninitialized)
 920
 921 # disable invalid "can't wrap" optimizations for signed / pointers
 922 KBUILD_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.
 927 KBUILD_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.
 931 KBUILD_CFLAGS   += $(call cc-option,-fmerge-constants)
 932
 933 # Make sure -fstack-check isn't enabled (like gentoo apparently did)
 934 KBUILD_CFLAGS  += $(call cc-option,-fno-stack-check,)
 935
 936 # conserve stack if available
 937 KBUILD_CFLAGS   += $(call cc-option,-fconserve-stack)
 938
 939 # Prohibit date/time macros, which would make the build non-deterministic
 940 KBUILD_CFLAGS   += $(call cc-option,-Werror=date-time)
 941
 942 # enforce correct pointer usage
 943 KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)
 944
 945 # Require designated initializers for all marked structures
 946 KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)
 947
 948 # change __FILE__ to the relative path from the srctree
 949 KBUILD_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
 953 ifdef CONFIG_RETPOLINE
 954 KBUILD_CFLAGS += $(call cc-option,-fcf-protection=none)
 955 endif
 956
 957 # include additional Makefiles when needed
 958 include-y                       := scripts/Makefile.extrawarn
 959 include-$(CONFIG_KASAN)         += scripts/Makefile.kasan
 960 include-$(CONFIG_KCSAN)         += scripts/Makefile.kcsan
 961 include-$(CONFIG_UBSAN)         += scripts/Makefile.ubsan
 962 include-$(CONFIG_KCOV)          += scripts/Makefile.kcov
 963 include-$(CONFIG_GCC_PLUGINS)   += scripts/Makefile.gcc-plugins
 964
 965 include $(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
 972 KBUILD_CPPFLAGS += $(KCPPFLAGS)
 973 KBUILD_AFLAGS   += $(KAFLAGS)
 974 KBUILD_CFLAGS   += $(KCFLAGS)
 975
 976 KBUILD_LDFLAGS_MODULE += --build-id
 977 LDFLAGS_vmlinux += --build-id
 978
 979 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
 980 LDFLAGS_vmlinux += $(call ld-option, -X,)
 981 endif
 982
 983 ifeq ($(CONFIG_RELR),y)
 984 LDFLAGS_vmlinux += --pack-dyn-relocs=relr
 985 endif
 986
 987 # Align the bit size of userspace programs with the kernel
 988 KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
 989 KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
 990
 991 # make the checker run with the right architecture
 992 CHECKFLAGS += --arch=$(ARCH)
 993
 994 # insure the checker run with the right endianness
 995 CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
 996
 997 # the checker needs the correct machine size
 998 CHECKFLAGS += $(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
1005 export 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
1010 export  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 #
1017 export 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
1025 MODLIB  = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1026 export 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
1034 ifdef INSTALL_MOD_STRIP
1035 ifeq ($(INSTALL_MOD_STRIP),1)
1036 mod_strip_cmd = $(STRIP) --strip-debug
1037 else
1038 mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
1039 endif # INSTALL_MOD_STRIP=1
1040 else
1041 mod_strip_cmd = true
1042 endif # INSTALL_MOD_STRIP
1043 export 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
1049 mod_compress_cmd = true
1050 ifdef 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
1057 endif # CONFIG_MODULE_COMPRESS
1058 export mod_compress_cmd
1059
1060 ifdef CONFIG_MODULE_SIG_ALL
1061 $(eval $(call config_filename,MODULE_SIG_KEY))
1062
1063 mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
1064 else
1065 mod_sign_cmd = true
1066 endif
1067 export mod_sign_cmd
1068
1069 HOST_LIBELF_LIBS = $(shell pkg-config libelf --libs 2>/dev/null || echo -lelf)
1070
1071 has_libelf = $(call try-run,\
1072                echo "int main() {}" | $(HOSTCC) -xc -o /dev/null $(HOST_LIBELF_LIBS) -,1,0)
1073
1074 ifdef CONFIG_STACK_VALIDATION
1075   ifeq ($(has_libelf),1)
1076     objtool_target := tools/objtool FORCE
1077   else
1078     SKIP_STACK_VALIDATION := 1
1079     export SKIP_STACK_VALIDATION
1080   endif
1081 endif
1082
1083 ifdef CONFIG_BPF
1084 ifdef CONFIG_DEBUG_INFO_BTF
1085   ifeq ($(has_libelf),1)
1086     resolve_btfids_target := tools/bpf/resolve_btfids FORCE
1087   else
1088     ERROR_RESOLVE_BTFIDS := 1
1089   endif
1090 endif # CONFIG_DEBUG_INFO_BTF
1091 endif # CONFIG_BPF
1092
1093 PHONY += prepare0
1094
1095 export MODORDER := $(extmod-prefix)modules.order
1096 export MODULES_NSDEPS := $(extmod-prefix)modules.nsdeps
1097
1098 ifeq ($(KBUILD_EXTMOD),)
1099 core-y          += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
1100
1101 vmlinux-dirs    := $(patsubst %/,%,$(filter %/, \
1102                      $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
1103                      $(libs-y) $(libs-m)))
1104
1105 vmlinux-alldirs := $(sort $(vmlinux-dirs) Documentation \
1106                      $(patsubst %/,%,$(filter %/, $(core-) \
1107                         $(drivers-) $(libs-))))
1108
1109 subdir-modorder := $(addsuffix modules.order,$(filter %/, \
1110                         $(core-y) $(core-m) $(libs-y) $(libs-m) \
1111                         $(drivers-y) $(drivers-m)))
1112
1113 build-dirs      := $(vmlinux-dirs)
1114 clean-dirs      := $(vmlinux-alldirs)
1115
1116 # Externally visible symbols (used by link-vmlinux.sh)
1117 KBUILD_VMLINUX_OBJS := $(head-y) $(patsubst %/,%/built-in.a, $(core-y))
1118 KBUILD_VMLINUX_OBJS += $(addsuffix built-in.a, $(filter %/, $(libs-y)))
1119 ifdef CONFIG_MODULES
1120 KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1121 KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1122 else
1123 KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1124 endif
1125 KBUILD_VMLINUX_OBJS += $(patsubst %/,%/built-in.a, $(drivers-y))
1126
1127 export KBUILD_VMLINUX_OBJS KBUILD_VMLINUX_LIBS
1128 export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1129 # used by scripts/Makefile.package
1130 export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) LICENSES arch include scripts tools)
1131
1132 vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
1133
1134 # Recurse until adjust_autoksyms.sh is satisfied
1135 PHONY += autoksyms_recursive
1136 ifdef CONFIG_TRIM_UNUSED_KSYMS
1137 # For the kernel to actually contain only the needed exported symbols,
1138 # we have to build modules as well to determine what those symbols are.
1139 # (this can be evaluated only once include/config/auto.conf has been included)
1140 KBUILD_MODULES := 1
1141
1142 autoksyms_recursive: descend modules.order
1143         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1144           "$(MAKE) -f $(srctree)/Makefile vmlinux"
1145 endif
1146
1147 autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1148
1149 quiet_cmd_autoksyms_h = GEN     $@
1150       cmd_autoksyms_h = mkdir -p $(dir $@); \
1151                         $(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@
1152
1153 $(autoksyms_h):
1154         $(call cmd,autoksyms_h)
1155
1156 ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1157
1158 # Final link of vmlinux with optional arch pass after final link
1159 cmd_link-vmlinux =                                                 \
1160         $(CONFIG_SHELL) $< "$(LD)" "$(KBUILD_LDFLAGS)" "$(LDFLAGS_vmlinux)";    \
1161         $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1162
1163 vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1164         +$(call if_changed,link-vmlinux)
1165
1166 targets := vmlinux
1167
1168 # The actual objects are generated when descending,
1169 # make sure no implicit rule kicks in
1170 $(sort $(vmlinux-deps) $(subdir-modorder)): descend ;
1171
1172 filechk_kernel.release = \
1173         echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1174
1175 # Store (new) KERNELRELEASE string in include/config/kernel.release
1176 include/config/kernel.release: FORCE
1177         $(call filechk,kernel.release)
1178
1179 # Additional helpers built in scripts/
1180 # Carefully list dependencies so we do not try to build scripts twice
1181 # in parallel
1182 PHONY += scripts
1183 scripts: scripts_basic scripts_dtc
1184         $(Q)$(MAKE) $(build)=$(@)
1185
1186 # Things we need to do before we recursively start building the kernel
1187 # or the modules are listed in "prepare".
1188 # A multi level approach is used. prepareN is processed before prepareN-1.
1189 # archprepare is used in arch Makefiles and when processed asm symlink,
1190 # version.h and scripts_basic is processed / created.
1191
1192 PHONY += prepare archprepare
1193
1194 archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1195         asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h \
1196         include/generated/autoconf.h
1197
1198 prepare0: archprepare
1199         $(Q)$(MAKE) $(build)=scripts/mod
1200         $(Q)$(MAKE) $(build)=.
1201
1202 # All the preparing..
1203 prepare: prepare0 prepare-objtool prepare-resolve_btfids
1204
1205 # Support for using generic headers in asm-generic
1206 asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1207
1208 PHONY += asm-generic uapi-asm-generic
1209 asm-generic: uapi-asm-generic
1210         $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1211         generic=include/asm-generic
1212 uapi-asm-generic:
1213         $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1214         generic=include/uapi/asm-generic
1215
1216 PHONY += prepare-objtool prepare-resolve_btfids
1217 prepare-objtool: $(objtool_target)
1218 ifeq ($(SKIP_STACK_VALIDATION),1)
1219 ifdef CONFIG_UNWINDER_ORC
1220         @echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1221         @false
1222 else
1223         @echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1224 endif
1225 endif
1226
1227 prepare-resolve_btfids: $(resolve_btfids_target)
1228 ifeq ($(ERROR_RESOLVE_BTFIDS),1)
1229         @echo "error: Cannot resolve BTF IDs for CONFIG_DEBUG_INFO_BTF, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1230         @false
1231 endif
1232 # Generate some files
1233 # ---------------------------------------------------------------------------
1234
1235 # KERNELRELEASE can change from a few different places, meaning version.h
1236 # needs to be updated, so this check is forced on all builds
1237
1238 uts_len := 64
1239 define filechk_utsrelease.h
1240         if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1241           echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1242           exit 1;                                                         \
1243         fi;                                                               \
1244         echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1245 endef
1246
1247 define filechk_version.h
1248         echo \#define LINUX_VERSION_CODE $(shell                         \
1249         expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1250         echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))'
1251 endef
1252
1253 $(version_h): FORCE
1254         $(call filechk,version.h)
1255         $(Q)rm -f $(old_version_h)
1256
1257 include/generated/utsrelease.h: include/config/kernel.release FORCE
1258         $(call filechk,utsrelease.h)
1259
1260 PHONY += headerdep
1261 headerdep:
1262         $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1263         $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1264
1265 # ---------------------------------------------------------------------------
1266 # Kernel headers
1267
1268 #Default location for installed headers
1269 export INSTALL_HDR_PATH = $(objtree)/usr
1270
1271 quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1272       cmd_headers_install = \
1273         mkdir -p $(INSTALL_HDR_PATH); \
1274         rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1275         usr/include $(INSTALL_HDR_PATH)
1276
1277 PHONY += headers_install
1278 headers_install: headers
1279         $(call cmd,headers_install)
1280
1281 PHONY += archheaders archscripts
1282
1283 hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1284
1285 PHONY += headers
1286 headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1287         $(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1288           $(error Headers not exportable for the $(SRCARCH) architecture))
1289         $(Q)$(MAKE) $(hdr-inst)=include/uapi
1290         $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1291
1292 # Deprecated. It is no-op now.
1293 PHONY += headers_check
1294 headers_check:
1295         @:
1296
1297 ifdef CONFIG_HEADERS_INSTALL
1298 prepare: headers
1299 endif
1300
1301 PHONY += scripts_unifdef
1302 scripts_unifdef: scripts_basic
1303         $(Q)$(MAKE) $(build)=scripts scripts/unifdef
1304
1305 # ---------------------------------------------------------------------------
1306 # Kernel selftest
1307
1308 PHONY += kselftest
1309 kselftest:
1310         $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1311
1312 kselftest-%: FORCE
1313         $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1314
1315 PHONY += kselftest-merge
1316 kselftest-merge:
1317         $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1318         $(Q)find $(srctree)/tools/testing/selftests -name config | \
1319                 xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1320         $(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1321
1322 # ---------------------------------------------------------------------------
1323 # Devicetree files
1324
1325 ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1326 dtstree := arch/$(SRCARCH)/boot/dts
1327 endif
1328
1329 ifneq ($(dtstree),)
1330
1331 %.dtb: include/config/kernel.release scripts_dtc
1332         $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1333
1334 PHONY += dtbs dtbs_install dtbs_check
1335 dtbs: include/config/kernel.release scripts_dtc
1336         $(Q)$(MAKE) $(build)=$(dtstree)
1337
1338 ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1339 export CHECK_DTBS=y
1340 dtbs: dt_binding_check
1341 endif
1342
1343 dtbs_check: dtbs
1344
1345 dtbs_install:
1346         $(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1347
1348 ifdef CONFIG_OF_EARLY_FLATTREE
1349 all: dtbs
1350 endif
1351
1352 endif
1353
1354 PHONY += scripts_dtc
1355 scripts_dtc: scripts_basic
1356         $(Q)$(MAKE) $(build)=scripts/dtc
1357
1358 ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1359 export CHECK_DT_BINDING=y
1360 endif
1361
1362 PHONY += dt_binding_check
1363 dt_binding_check: scripts_dtc
1364         $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1365
1366 # ---------------------------------------------------------------------------
1367 # Modules
1368
1369 ifdef CONFIG_MODULES
1370
1371 # By default, build modules as well
1372
1373 all: modules
1374
1375 # When we're building modules with modversions, we need to consider
1376 # the built-in objects during the descend as well, in order to
1377 # make sure the checksums are up to date before we record them.
1378 ifdef CONFIG_MODVERSIONS
1379   KBUILD_BUILTIN := 1
1380 endif
1381
1382 # Build modules
1383 #
1384 # A module can be listed more than once in obj-m resulting in
1385 # duplicate lines in modules.order files.  Those are removed
1386 # using awk while concatenating to the final file.
1387
1388 PHONY += modules
1389 modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_check
1390         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1391
1392 PHONY += modules_check
1393 modules_check: modules.order
1394         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1395
1396 cmd_modules_order = $(AWK) '!x[$$0]++' $(real-prereqs) > $@
1397
1398 modules.order: $(subdir-modorder) FORCE
1399         $(call if_changed,modules_order)
1400
1401 targets += modules.order
1402
1403 # Target to prepare building external modules
1404 PHONY += modules_prepare
1405 modules_prepare: prepare
1406
1407 # Target to install modules
1408 PHONY += modules_install
1409 modules_install: _modinst_ _modinst_post
1410
1411 PHONY += _modinst_
1412 _modinst_:
1413         @rm -rf $(MODLIB)/kernel
1414         @rm -f $(MODLIB)/source
1415         @mkdir -p $(MODLIB)/kernel
1416         @ln -s $(abspath $(srctree)) $(MODLIB)/source
1417         @if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
1418                 rm -f $(MODLIB)/build ; \
1419                 ln -s $(CURDIR) $(MODLIB)/build ; \
1420         fi
1421         @sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order
1422         @cp -f modules.builtin $(MODLIB)/
1423         @cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
1424         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1425
1426 # This depmod is only for convenience to give the initial
1427 # boot a modules.dep even before / is mounted read-write.  However the
1428 # boot script depmod is the master version.
1429 PHONY += _modinst_post
1430 _modinst_post: _modinst_
1431         $(call cmd,depmod)
1432
1433 ifeq ($(CONFIG_MODULE_SIG), y)
1434 PHONY += modules_sign
1435 modules_sign:
1436         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1437 endif
1438
1439 else # CONFIG_MODULES
1440
1441 # Modules not configured
1442 # ---------------------------------------------------------------------------
1443
1444 PHONY += modules modules_install
1445 modules modules_install:
1446         @echo >&2
1447         @echo >&2 "The present kernel configuration has modules disabled."
1448         @echo >&2 "Type 'make config' and enable loadable module support."
1449         @echo >&2 "Then build a kernel with module support enabled."
1450         @echo >&2
1451         @exit 1
1452
1453 endif # CONFIG_MODULES
1454
1455 ###
1456 # Cleaning is done on three levels.
1457 # make clean     Delete most generated files
1458 #                Leave enough to build external modules
1459 # make mrproper  Delete the current configuration, and all generated files
1460 # make distclean Remove editor backup files, patch leftover files and the like
1461
1462 # Directories & files removed with 'make clean'
1463 CLEAN_FILES += include/ksym vmlinux.symvers \
1464                modules.builtin modules.builtin.modinfo modules.nsdeps
1465
1466 # Directories & files removed with 'make mrproper'
1467 MRPROPER_FILES += include/config include/generated          \
1468                   arch/$(SRCARCH)/include/generated .tmp_objdiff \
1469                   debian snap tar-install \
1470                   .config .config.old .version \
1471                   Module.symvers \
1472                   signing_key.pem signing_key.priv signing_key.x509     \
1473                   x509.genkey extra_certificates signing_key.x509.keyid \
1474                   signing_key.x509.signer vmlinux-gdb.py \
1475                   *.spec
1476
1477 # Directories & files removed with 'make distclean'
1478 DISTCLEAN_FILES += tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS
1479
1480 # clean - Delete most, but leave enough to build external modules
1481 #
1482 clean: rm-files := $(CLEAN_FILES)
1483
1484 PHONY += archclean vmlinuxclean
1485
1486 vmlinuxclean:
1487         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1488         $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1489
1490 clean: archclean vmlinuxclean
1491
1492 # mrproper - Delete all generated files, including .config
1493 #
1494 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1495 mrproper-dirs      := $(addprefix _mrproper_,scripts)
1496
1497 PHONY += $(mrproper-dirs) mrproper
1498 $(mrproper-dirs):
1499         $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1500
1501 mrproper: clean $(mrproper-dirs)
1502         $(call cmd,rmfiles)
1503
1504 # distclean
1505 #
1506 distclean: rm-files := $(wildcard $(DISTCLEAN_FILES))
1507
1508 PHONY += distclean
1509
1510 distclean: mrproper
1511         $(call cmd,rmfiles)
1512         @find $(srctree) $(RCS_FIND_IGNORE) \
1513                 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1514                 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1515                 -o -name 'core' \) \
1516                 -type f -print | xargs rm -f
1517
1518
1519 # Packaging of the kernel to various formats
1520 # ---------------------------------------------------------------------------
1521
1522 %src-pkg: FORCE
1523         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1524 %pkg: include/config/kernel.release FORCE
1525         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1526
1527 # Brief documentation of the typical targets used
1528 # ---------------------------------------------------------------------------
1529
1530 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1531 boards := $(sort $(notdir $(boards)))
1532 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1533 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1534
1535 PHONY += help
1536 help:
1537         @echo  'Cleaning targets:'
1538         @echo  '  clean           - Remove most generated files but keep the config and'
1539         @echo  '                    enough build support to build external modules'
1540         @echo  '  mrproper        - Remove all generated files + config + various backup files'
1541         @echo  '  distclean       - mrproper + remove editor backup and patch files'
1542         @echo  ''
1543         @echo  'Configuration targets:'
1544         @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1545         @echo  ''
1546         @echo  'Other generic targets:'
1547         @echo  '  all             - Build all targets marked with [*]'
1548         @echo  '* vmlinux         - Build the bare kernel'
1549         @echo  '* modules         - Build all modules'
1550         @echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1551         @echo  '  dir/            - Build all files in dir and below'
1552         @echo  '  dir/file.[ois]  - Build specified target only'
1553         @echo  '  dir/file.ll     - Build the LLVM assembly file'
1554         @echo  '                    (requires compiler support for LLVM assembly generation)'
1555         @echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1556         @echo  '                    (requires a recent binutils and recent build (System.map))'
1557         @echo  '  dir/file.ko     - Build module including final link'
1558         @echo  '  modules_prepare - Set up for building external modules'
1559         @echo  '  tags/TAGS       - Generate tags file for editors'
1560         @echo  '  cscope          - Generate cscope index'
1561         @echo  '  gtags           - Generate GNU GLOBAL index'
1562         @echo  '  kernelrelease   - Output the release version string (use with make -s)'
1563         @echo  '  kernelversion   - Output the version stored in Makefile (use with make -s)'
1564         @echo  '  image_name      - Output the image name (use with make -s)'
1565         @echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1566          echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1567          echo  ''
1568         @echo  'Static analysers:'
1569         @echo  '  checkstack      - Generate a list of stack hogs'
1570         @echo  '  namespacecheck  - Name space analysis on compiled kernel'
1571         @echo  '  versioncheck    - Sanity check on version.h usage'
1572         @echo  '  includecheck    - Check for duplicate included header files'
1573         @echo  '  export_report   - List the usages of all exported symbols'
1574         @echo  '  headerdep       - Detect inclusion cycles in headers'
1575         @echo  '  coccicheck      - Check with Coccinelle'
1576         @echo  ''
1577         @echo  'Tools:'
1578         @echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1579         @echo  ''
1580         @echo  'Kernel selftest:'
1581         @echo  '  kselftest         - Build and run kernel selftest'
1582         @echo  '                      Build, install, and boot kernel before'
1583         @echo  '                      running kselftest on it'
1584         @echo  '                      Run as root for full coverage'
1585         @echo  '  kselftest-all     - Build kernel selftest'
1586         @echo  '  kselftest-install - Build and install kernel selftest'
1587         @echo  '  kselftest-clean   - Remove all generated kselftest files'
1588         @echo  '  kselftest-merge   - Merge all the config dependencies of'
1589         @echo  '                      kselftest to existing .config.'
1590         @echo  ''
1591         @$(if $(dtstree), \
1592                 echo 'Devicetree:'; \
1593                 echo '* dtbs             - Build device tree blobs for enabled boards'; \
1594                 echo '  dtbs_install     - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1595                 echo '  dt_binding_check - Validate device tree binding documents'; \
1596                 echo '  dtbs_check       - Validate device tree source files';\
1597                 echo '')
1598
1599         @echo 'Userspace tools targets:'
1600         @echo '  use "make tools/help"'
1601         @echo '  or  "cd tools; make help"'
1602         @echo  ''
1603         @echo  'Kernel packaging:'
1604         @$(MAKE) -f $(srctree)/scripts/Makefile.package help
1605         @echo  ''
1606         @echo  'Documentation targets:'
1607         @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1608         @echo  ''
1609         @echo  'Architecture specific targets ($(SRCARCH)):'
1610         @$(if $(archhelp),$(archhelp),\
1611                 echo '  No architecture specific help defined for $(SRCARCH)')
1612         @echo  ''
1613         @$(if $(boards), \
1614                 $(foreach b, $(boards), \
1615                 printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1616                 echo '')
1617         @$(if $(board-dirs), \
1618                 $(foreach b, $(board-dirs), \
1619                 printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1620                 printf "  %-16s - Show all of the above\\n" help-boards; \
1621                 echo '')
1622
1623         @echo  '  make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1624         @echo  '  make V=2   [targets] 2 => give reason for rebuild of target'
1625         @echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1626         @echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1627         @echo  '                       (sparse by default)'
1628         @echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1629         @echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1630         @echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
1631         @echo  '                1: warnings which may be relevant and do not occur too often'
1632         @echo  '                2: warnings which occur quite often but may still be relevant'
1633         @echo  '                3: more obscure warnings, can most likely be ignored'
1634         @echo  '                Multiple levels can be combined with W=12 or W=123'
1635         @echo  ''
1636         @echo  'Execute "make" or "make all" to build all targets marked with [*] '
1637         @echo  'For further info see the ./README file'
1638
1639
1640 help-board-dirs := $(addprefix help-,$(board-dirs))
1641
1642 help-boards: $(help-board-dirs)
1643
1644 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1645
1646 $(help-board-dirs): help-%:
1647         @echo  'Architecture specific targets ($(SRCARCH) $*):'
1648         @$(if $(boards-per-dir), \
1649                 $(foreach b, $(boards-per-dir), \
1650                 printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1651                 echo '')
1652
1653
1654 # Documentation targets
1655 # ---------------------------------------------------------------------------
1656 DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1657                linkcheckdocs dochelp refcheckdocs
1658 PHONY += $(DOC_TARGETS)
1659 $(DOC_TARGETS):
1660         $(Q)$(MAKE) $(build)=Documentation $@
1661
1662 # Misc
1663 # ---------------------------------------------------------------------------
1664
1665 PHONY += scripts_gdb
1666 scripts_gdb: prepare0
1667         $(Q)$(MAKE) $(build)=scripts/gdb
1668         $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1669
1670 ifdef CONFIG_GDB_SCRIPTS
1671 all: scripts_gdb
1672 endif
1673
1674 else # KBUILD_EXTMOD
1675
1676 ###
1677 # External module support.
1678 # When building external modules the kernel used as basis is considered
1679 # read-only, and no consistency checks are made and the make
1680 # system is not used on the basis kernel. If updates are required
1681 # in the basis kernel ordinary make commands (without M=...) must
1682 # be used.
1683 #
1684 # The following are the only valid targets when building external
1685 # modules.
1686 # make M=dir clean     Delete all automatically generated files
1687 # make M=dir modules   Make all modules in specified dir
1688 # make M=dir           Same as 'make M=dir modules'
1689 # make M=dir modules_install
1690 #                      Install the modules built in the module directory
1691 #                      Assumes install directory is already created
1692
1693 # We are always building modules
1694 KBUILD_MODULES := 1
1695
1696 build-dirs := $(KBUILD_EXTMOD)
1697 PHONY += modules
1698 modules: descend
1699         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1700
1701 PHONY += modules_install
1702 modules_install: _emodinst_ _emodinst_post
1703
1704 install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1705 PHONY += _emodinst_
1706 _emodinst_:
1707         $(Q)mkdir -p $(MODLIB)/$(install-dir)
1708         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1709
1710 PHONY += _emodinst_post
1711 _emodinst_post: _emodinst_
1712         $(call cmd,depmod)
1713
1714 clean-dirs := $(KBUILD_EXTMOD)
1715 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps
1716
1717 PHONY += help
1718 help:
1719         @echo  '  Building external modules.'
1720         @echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1721         @echo  ''
1722         @echo  '  modules         - default target, build the module(s)'
1723         @echo  '  modules_install - install the module'
1724         @echo  '  clean           - remove generated files in module directory only'
1725         @echo  ''
1726
1727 PHONY += prepare
1728 endif # KBUILD_EXTMOD
1729
1730 # Single targets
1731 # ---------------------------------------------------------------------------
1732 # To build individual files in subdirectories, you can do like this:
1733 #
1734 #   make foo/bar/baz.s
1735 #
1736 # The supported suffixes for single-target are listed in 'single-targets'
1737 #
1738 # To build only under specific subdirectories, you can do like this:
1739 #
1740 #   make foo/bar/baz/
1741
1742 ifdef single-build
1743
1744 # .ko is special because modpost is needed
1745 single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1746 single-no-ko := $(sort $(patsubst %.ko,%.mod, $(MAKECMDGOALS)))
1747
1748 $(single-ko): single_modpost
1749         @:
1750 $(single-no-ko): descend
1751         @:
1752
1753 ifeq ($(KBUILD_EXTMOD),)
1754 # For the single build of in-tree modules, use a temporary file to avoid
1755 # the situation of modules_install installing an invalid modules.order.
1756 MODORDER := .modules.tmp
1757 endif
1758
1759 PHONY += single_modpost
1760 single_modpost: $(single-no-ko)
1761         $(Q){ $(foreach m, $(single-ko), echo $(extmod-prefix)$m;) } > $(MODORDER)
1762         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1763
1764 KBUILD_MODULES := 1
1765
1766 export KBUILD_SINGLE_TARGETS := $(addprefix $(extmod-prefix), $(single-no-ko))
1767
1768 # trim unrelated directories
1769 build-dirs := $(foreach d, $(build-dirs), \
1770                         $(if $(filter $(d)/%, $(KBUILD_SINGLE_TARGETS)), $(d)))
1771
1772 endif
1773
1774 ifndef CONFIG_MODULES
1775 KBUILD_MODULES :=
1776 endif
1777
1778 # Handle descending into subdirectories listed in $(build-dirs)
1779 # Preset locale variables to speed up the build process. Limit locale
1780 # tweaks to this spot to avoid wrong language settings when running
1781 # make menuconfig etc.
1782 # Error messages still appears in the original language
1783 PHONY += descend $(build-dirs)
1784 descend: $(build-dirs)
1785 $(build-dirs): prepare
1786         $(Q)$(MAKE) $(build)=$@ \
1787         single-build=$(if $(filter-out $@/, $(filter $@/%, $(KBUILD_SINGLE_TARGETS))),1) \
1788         need-builtin=1 need-modorder=1
1789
1790 clean-dirs := $(addprefix _clean_, $(clean-dirs))
1791 PHONY += $(clean-dirs) clean
1792 $(clean-dirs):
1793         $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1794
1795 clean: $(clean-dirs)
1796         $(call cmd,rmfiles)
1797         @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1798                 \( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1799                 -o -name '*.ko.*' \
1800                 -o -name '*.dtb' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1801                 -o -name '*.dwo' -o -name '*.lst' \
1802                 -o -name '*.su' -o -name '*.mod' \
1803                 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1804                 -o -name '*.lex.c' -o -name '*.tab.[ch]' \
1805                 -o -name '*.asn1.[ch]' \
1806                 -o -name '*.symtypes' -o -name 'modules.order' \
1807                 -o -name '.tmp_*.o.*' \
1808                 -o -name '*.c.[012]*.*' \
1809                 -o -name '*.ll' \
1810                 -o -name '*.gcno' \) -type f -print | xargs rm -f
1811
1812 # Generate tags for editors
1813 # ---------------------------------------------------------------------------
1814 quiet_cmd_tags = GEN     $@
1815       cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1816
1817 tags TAGS cscope gtags: FORCE
1818         $(call cmd,tags)
1819
1820 # Script to generate missing namespace dependencies
1821 # ---------------------------------------------------------------------------
1822
1823 PHONY += nsdeps
1824 nsdeps: export KBUILD_NSDEPS=1
1825 nsdeps: modules
1826         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1827
1828 # Scripts to check various things for consistency
1829 # ---------------------------------------------------------------------------
1830
1831 PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1832
1833 includecheck:
1834         find $(srctree)/* $(RCS_FIND_IGNORE) \
1835                 -name '*.[hcS]' -type f -print | sort \
1836                 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1837
1838 versioncheck:
1839         find $(srctree)/* $(RCS_FIND_IGNORE) \
1840                 -name '*.[hcS]' -type f -print | sort \
1841                 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1842
1843 coccicheck:
1844         $(Q)$(BASH) $(srctree)/scripts/$@
1845
1846 namespacecheck:
1847         $(PERL) $(srctree)/scripts/namespace.pl
1848
1849 export_report:
1850         $(PERL) $(srctree)/scripts/export_report.pl
1851
1852 PHONY += checkstack kernelrelease kernelversion image_name
1853
1854 # UML needs a little special treatment here.  It wants to use the host
1855 # toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
1856 # else wants $(ARCH), including people doing cross-builds, which means
1857 # that $(SUBARCH) doesn't work here.
1858 ifeq ($(ARCH), um)
1859 CHECKSTACK_ARCH := $(SUBARCH)
1860 else
1861 CHECKSTACK_ARCH := $(ARCH)
1862 endif
1863 checkstack:
1864         $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1865         $(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1866
1867 kernelrelease:
1868         @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1869
1870 kernelversion:
1871         @echo $(KERNELVERSION)
1872
1873 image_name:
1874         @echo $(KBUILD_IMAGE)
1875
1876 # Clear a bunch of variables before executing the submake
1877
1878 ifeq ($(quiet),silent_)
1879 tools_silent=s
1880 endif
1881
1882 tools/: FORCE
1883         $(Q)mkdir -p $(objtree)/tools
1884         $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1885
1886 tools/%: FORCE
1887         $(Q)mkdir -p $(objtree)/tools
1888         $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1889
1890 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
1891       cmd_rmfiles = rm -rf $(rm-files)
1892
1893 # Run depmod only if we have System.map and depmod is executable
1894 quiet_cmd_depmod = DEPMOD  $(KERNELRELEASE)
1895       cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1896                    $(KERNELRELEASE)
1897
1898 # read saved command lines for existing targets
1899 existing-targets := $(wildcard $(sort $(targets)))
1900
1901 -include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
1902
1903 endif # config-build
1904 endif # mixed-build
1905 endif # need-sub-make
1906
1907 PHONY += FORCE
1908 FORCE:
1909
1910 # Declare the contents of the PHONY variable as phony.  We keep that
1911 # information in a variable so we can use it in if_changed and friends.
1912 .PHONY: $(PHONY)