Makefile

   1 # SPDX-License-Identifier: GPL-2.0
   2 VERSION = 5
   3 PATCHLEVEL = 7
   4 SUBLEVEL = 0
   5 EXTRAVERSION = -rc5
   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 export KBUILD_CHECKSRC KBUILD_EXTMOD
 222
 223 extmod-prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
 224
 225 ifeq ($(abs_srctree),$(abs_objtree))
 226         # building in the source tree
 227         srctree := .
 228         building_out_of_srctree :=
 229 else
 230         ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
 231                 # building in a subdirectory of the source tree
 232                 srctree := ..
 233         else
 234                 srctree := $(abs_srctree)
 235         endif
 236         building_out_of_srctree := 1
 237 endif
 238
 239 ifneq ($(KBUILD_ABS_SRCTREE),)
 240 srctree := $(abs_srctree)
 241 endif
 242
 243 objtree         := .
 244 VPATH           := $(srctree)
 245
 246 export building_out_of_srctree srctree objtree VPATH
 247
 248 # To make sure we do not include .config for any of the *config targets
 249 # catch them early, and hand them over to scripts/kconfig/Makefile
 250 # It is allowed to specify more targets when calling make, including
 251 # mixing *config targets and build targets.
 252 # For example 'make oldconfig all'.
 253 # Detect when mixed targets is specified, and make a second invocation
 254 # of make so .config is not included in this case either (for *config).
 255
 256 version_h := include/generated/uapi/linux/version.h
 257 old_version_h := include/linux/version.h
 258
 259 clean-targets := %clean mrproper cleandocs
 260 no-dot-config-targets := $(clean-targets) \
 261                          cscope gtags TAGS tags help% %docs check% coccicheck \
 262                          $(version_h) headers headers_% archheaders archscripts \
 263                          %asm-generic kernelversion %src-pkg dt_binding_check \
 264                          outputmakefile
 265 no-sync-config-targets := $(no-dot-config-targets) install %install \
 266                            kernelrelease
 267 single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
 268
 269 config-build    :=
 270 mixed-build     :=
 271 need-config     := 1
 272 may-sync-config := 1
 273 single-build    :=
 274
 275 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
 276         ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
 277                 need-config :=
 278         endif
 279 endif
 280
 281 ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
 282         ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
 283                 may-sync-config :=
 284         endif
 285 endif
 286
 287 ifneq ($(KBUILD_EXTMOD),)
 288         may-sync-config :=
 289 endif
 290
 291 ifeq ($(KBUILD_EXTMOD),)
 292         ifneq ($(filter config %config,$(MAKECMDGOALS)),)
 293                 config-build := 1
 294                 ifneq ($(words $(MAKECMDGOALS)),1)
 295                         mixed-build := 1
 296                 endif
 297         endif
 298 endif
 299
 300 # We cannot build single targets and the others at the same time
 301 ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
 302         single-build := 1
 303         ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
 304                 mixed-build := 1
 305         endif
 306 endif
 307
 308 # For "make -j clean all", "make -j mrproper defconfig all", etc.
 309 ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
 310         ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
 311                 mixed-build := 1
 312         endif
 313 endif
 314
 315 # install and modules_install need also be processed one by one
 316 ifneq ($(filter install,$(MAKECMDGOALS)),)
 317         ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
 318                 mixed-build := 1
 319         endif
 320 endif
 321
 322 ifdef mixed-build
 323 # ===========================================================================
 324 # We're called with mixed targets (*config and build targets).
 325 # Handle them one by one.
 326
 327 PHONY += $(MAKECMDGOALS) __build_one_by_one
 328
 329 $(MAKECMDGOALS): __build_one_by_one
 330         @:
 331
 332 __build_one_by_one:
 333         $(Q)set -e; \
 334         for i in $(MAKECMDGOALS); do \
 335                 $(MAKE) -f $(srctree)/Makefile $$i; \
 336         done
 337
 338 else # !mixed-build
 339
 340 include scripts/Kbuild.include
 341
 342 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
 343 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
 344 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
 345 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
 346
 347 include scripts/subarch.include
 348
 349 # Cross compiling and selecting different set of gcc/bin-utils
 350 # ---------------------------------------------------------------------------
 351 #
 352 # When performing cross compilation for other architectures ARCH shall be set
 353 # to the target architecture. (See arch/* for the possibilities).
 354 # ARCH can be set during invocation of make:
 355 # make ARCH=ia64
 356 # Another way is to have ARCH set in the environment.
 357 # The default ARCH is the host where make is executed.
 358
 359 # CROSS_COMPILE specify the prefix used for all executables used
 360 # during compilation. Only gcc and related bin-utils executables
 361 # are prefixed with $(CROSS_COMPILE).
 362 # CROSS_COMPILE can be set on the command line
 363 # make CROSS_COMPILE=ia64-linux-
 364 # Alternatively CROSS_COMPILE can be set in the environment.
 365 # Default value for CROSS_COMPILE is not to prefix executables
 366 # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
 367 ARCH            ?= $(SUBARCH)
 368
 369 # Architecture as present in compile.h
 370 UTS_MACHINE     := $(ARCH)
 371 SRCARCH         := $(ARCH)
 372
 373 # Additional ARCH settings for x86
 374 ifeq ($(ARCH),i386)
 375         SRCARCH := x86
 376 endif
 377 ifeq ($(ARCH),x86_64)
 378         SRCARCH := x86
 379 endif
 380
 381 # Additional ARCH settings for sparc
 382 ifeq ($(ARCH),sparc32)
 383        SRCARCH := sparc
 384 endif
 385 ifeq ($(ARCH),sparc64)
 386        SRCARCH := sparc
 387 endif
 388
 389 # Additional ARCH settings for sh
 390 ifeq ($(ARCH),sh64)
 391        SRCARCH := sh
 392 endif
 393
 394 KCONFIG_CONFIG  ?= .config
 395 export KCONFIG_CONFIG
 396
 397 # Default file for 'make defconfig'. This may be overridden by arch-Makefile.
 398 export KBUILD_DEFCONFIG := defconfig
 399
 400 # SHELL used by kbuild
 401 CONFIG_SHELL := sh
 402
 403 HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
 404 HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
 405 HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
 406
 407 ifneq ($(LLVM),)
 408 HOSTCC  = clang
 409 HOSTCXX = clang++
 410 else
 411 HOSTCC  = gcc
 412 HOSTCXX = g++
 413 endif
 414
 415 export KBUILD_USERCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
 416                               -O2 -fomit-frame-pointer -std=gnu89
 417 export KBUILD_USERLDFLAGS :=
 418
 419 KBUILD_HOSTCFLAGS   := $(KBUILD_USERCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
 420 KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
 421 KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
 422 KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
 423
 424 # Make variables (CC, etc...)
 425 CPP             = $(CC) -E
 426 ifneq ($(LLVM),)
 427 CC              = clang
 428 LD              = ld.lld
 429 AR              = llvm-ar
 430 NM              = llvm-nm
 431 OBJCOPY         = llvm-objcopy
 432 OBJDUMP         = llvm-objdump
 433 READELF         = llvm-readelf
 434 OBJSIZE         = llvm-size
 435 STRIP           = llvm-strip
 436 else
 437 CC              = $(CROSS_COMPILE)gcc
 438 LD              = $(CROSS_COMPILE)ld
 439 AR              = $(CROSS_COMPILE)ar
 440 NM              = $(CROSS_COMPILE)nm
 441 OBJCOPY         = $(CROSS_COMPILE)objcopy
 442 OBJDUMP         = $(CROSS_COMPILE)objdump
 443 READELF         = $(CROSS_COMPILE)readelf
 444 OBJSIZE         = $(CROSS_COMPILE)size
 445 STRIP           = $(CROSS_COMPILE)strip
 446 endif
 447 PAHOLE          = pahole
 448 LEX             = flex
 449 YACC            = bison
 450 AWK             = awk
 451 INSTALLKERNEL  := installkernel
 452 DEPMOD          = /sbin/depmod
 453 PERL            = perl
 454 PYTHON          = python
 455 PYTHON3         = python3
 456 CHECK           = sparse
 457 BASH            = bash
 458
 459 CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
 460                   -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
 461 NOSTDINC_FLAGS :=
 462 CFLAGS_MODULE   =
 463 AFLAGS_MODULE   =
 464 LDFLAGS_MODULE  =
 465 CFLAGS_KERNEL   =
 466 AFLAGS_KERNEL   =
 467 LDFLAGS_vmlinux =
 468
 469 # Use USERINCLUDE when you must reference the UAPI directories only.
 470 USERINCLUDE    := \
 471                 -I$(srctree)/arch/$(SRCARCH)/include/uapi \
 472                 -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
 473                 -I$(srctree)/include/uapi \
 474                 -I$(objtree)/include/generated/uapi \
 475                 -include $(srctree)/include/linux/kconfig.h
 476
 477 # Use LINUXINCLUDE when you must reference the include/ directory.
 478 # Needed to be compatible with the O= option
 479 LINUXINCLUDE    := \
 480                 -I$(srctree)/arch/$(SRCARCH)/include \
 481                 -I$(objtree)/arch/$(SRCARCH)/include/generated \
 482                 $(if $(building_out_of_srctree),-I$(srctree)/include) \
 483                 -I$(objtree)/include \
 484                 $(USERINCLUDE)
 485
 486 KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
 487 KBUILD_CFLAGS   := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
 488                    -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
 489                    -Werror=implicit-function-declaration -Werror=implicit-int \
 490                    -Wno-format-security \
 491                    -std=gnu89
 492 KBUILD_CPPFLAGS := -D__KERNEL__
 493 KBUILD_AFLAGS_KERNEL :=
 494 KBUILD_CFLAGS_KERNEL :=
 495 KBUILD_AFLAGS_MODULE  := -DMODULE
 496 KBUILD_CFLAGS_MODULE  := -DMODULE
 497 KBUILD_LDFLAGS_MODULE :=
 498 export KBUILD_LDS_MODULE := $(srctree)/scripts/module-common.lds
 499 KBUILD_LDFLAGS :=
 500 GCC_PLUGINS_CFLAGS :=
 501 CLANG_FLAGS :=
 502
 503 export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC
 504 export CPP AR NM STRIP OBJCOPY OBJDUMP OBJSIZE READELF PAHOLE LEX YACC AWK INSTALLKERNEL
 505 export PERL PYTHON PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
 506 export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
 507
 508 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
 509 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
 510 export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN
 511 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
 512 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
 513 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
 514
 515 # Files to ignore in find ... statements
 516
 517 export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
 518                           -name CVS -o -name .pc -o -name .hg -o -name .git \) \
 519                           -prune -o
 520 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
 521                          --exclude CVS --exclude .pc --exclude .hg --exclude .git
 522
 523 # ===========================================================================
 524 # Rules shared between *config targets and build targets
 525
 526 # Basic helpers built in scripts/basic/
 527 PHONY += scripts_basic
 528 scripts_basic:
 529         $(Q)$(MAKE) $(build)=scripts/basic
 530         $(Q)rm -f .tmp_quiet_recordmcount
 531
 532 PHONY += outputmakefile
 533 # Before starting out-of-tree build, make sure the source tree is clean.
 534 # outputmakefile generates a Makefile in the output directory, if using a
 535 # separate output directory. This allows convenient use of make in the
 536 # output directory.
 537 # At the same time when output Makefile generated, generate .gitignore to
 538 # ignore whole output directory
 539 outputmakefile:
 540 ifdef building_out_of_srctree
 541         $(Q)if [ -f $(srctree)/.config -o \
 542                  -d $(srctree)/include/config -o \
 543                  -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
 544                 echo >&2 "***"; \
 545                 echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
 546                 echo >&2 "*** in $(abs_srctree)";\
 547                 echo >&2 "***"; \
 548                 false; \
 549         fi
 550         $(Q)ln -fsn $(srctree) source
 551         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile $(srctree)
 552         $(Q)test -e .gitignore || \
 553         { echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
 554 endif
 555
 556 ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),)
 557 ifneq ($(CROSS_COMPILE),)
 558 CLANG_FLAGS     += --target=$(notdir $(CROSS_COMPILE:%-=%))
 559 GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
 560 CLANG_FLAGS     += --prefix=$(GCC_TOOLCHAIN_DIR)
 561 GCC_TOOLCHAIN   := $(realpath $(GCC_TOOLCHAIN_DIR)/..)
 562 endif
 563 ifneq ($(GCC_TOOLCHAIN),)
 564 CLANG_FLAGS     += --gcc-toolchain=$(GCC_TOOLCHAIN)
 565 endif
 566 ifneq ($(LLVM_IAS),1)
 567 CLANG_FLAGS     += -no-integrated-as
 568 endif
 569 CLANG_FLAGS     += -Werror=unknown-warning-option
 570 KBUILD_CFLAGS   += $(CLANG_FLAGS)
 571 KBUILD_AFLAGS   += $(CLANG_FLAGS)
 572 export CLANG_FLAGS
 573 endif
 574
 575 # The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
 576 # Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
 577 # CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
 578 # and from include/config/auto.conf.cmd to detect the compiler upgrade.
 579 CC_VERSION_TEXT = $(shell $(CC) --version 2>/dev/null | head -n 1)
 580
 581 ifdef config-build
 582 # ===========================================================================
 583 # *config targets only - make sure prerequisites are updated, and descend
 584 # in scripts/kconfig to make the *config target
 585
 586 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
 587 # KBUILD_DEFCONFIG may point out an alternative default configuration
 588 # used for 'make defconfig'
 589 include arch/$(SRCARCH)/Makefile
 590 export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
 591
 592 config: outputmakefile scripts_basic FORCE
 593         $(Q)$(MAKE) $(build)=scripts/kconfig $@
 594
 595 %config: outputmakefile scripts_basic FORCE
 596         $(Q)$(MAKE) $(build)=scripts/kconfig $@
 597
 598 else #!config-build
 599 # ===========================================================================
 600 # Build targets only - this includes vmlinux, arch specific targets, clean
 601 # targets and others. In general all targets except *config targets.
 602
 603 # If building an external module we do not care about the all: rule
 604 # but instead __all depend on modules
 605 PHONY += all
 606 ifeq ($(KBUILD_EXTMOD),)
 607 __all: all
 608 else
 609 __all: modules
 610 endif
 611
 612 # Decide whether to build built-in, modular, or both.
 613 # Normally, just do built-in.
 614
 615 KBUILD_MODULES :=
 616 KBUILD_BUILTIN := 1
 617
 618 # If we have only "make modules", don't compile built-in objects.
 619 # When we're building modules with modversions, we need to consider
 620 # the built-in objects during the descend as well, in order to
 621 # make sure the checksums are up to date before we record them.
 622
 623 ifeq ($(MAKECMDGOALS),modules)
 624   KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
 625 endif
 626
 627 # If we have "make <whatever> modules", compile modules
 628 # in addition to whatever we do anyway.
 629 # Just "make" or "make all" shall build modules as well
 630
 631 ifneq ($(filter all modules nsdeps,$(MAKECMDGOALS)),)
 632   KBUILD_MODULES := 1
 633 endif
 634
 635 ifeq ($(MAKECMDGOALS),)
 636   KBUILD_MODULES := 1
 637 endif
 638
 639 export KBUILD_MODULES KBUILD_BUILTIN
 640
 641 ifdef need-config
 642 include include/config/auto.conf
 643 endif
 644
 645 ifeq ($(KBUILD_EXTMOD),)
 646 # Objects we will link into vmlinux / subdirs we need to visit
 647 init-y          := init/
 648 drivers-y       := drivers/ sound/
 649 drivers-$(CONFIG_SAMPLES) += samples/
 650 net-y           := net/
 651 libs-y          := lib/
 652 core-y          := usr/
 653 virt-y          := virt/
 654 endif # KBUILD_EXTMOD
 655
 656 # The all: target is the default when no target is given on the
 657 # command line.
 658 # This allow a user to issue only 'make' to build a kernel including modules
 659 # Defaults to vmlinux, but the arch makefile usually adds further targets
 660 all: vmlinux
 661
 662 CFLAGS_GCOV     := -fprofile-arcs -ftest-coverage \
 663         $(call cc-option,-fno-tree-loop-im) \
 664         $(call cc-disable-warning,maybe-uninitialized,)
 665 export CFLAGS_GCOV
 666
 667 # The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
 668 ifdef CONFIG_FUNCTION_TRACER
 669   CC_FLAGS_FTRACE := -pg
 670 endif
 671
 672 RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
 673 RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
 674 RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
 675 RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
 676 RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
 677 RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
 678 export RETPOLINE_CFLAGS
 679 export RETPOLINE_VDSO_CFLAGS
 680
 681 include arch/$(SRCARCH)/Makefile
 682
 683 ifdef need-config
 684 ifdef may-sync-config
 685 # Read in dependencies to all Kconfig* files, make sure to run syncconfig if
 686 # changes are detected. This should be included after arch/$(SRCARCH)/Makefile
 687 # because some architectures define CROSS_COMPILE there.
 688 include include/config/auto.conf.cmd
 689
 690 $(KCONFIG_CONFIG):
 691         @echo >&2 '***'
 692         @echo >&2 '*** Configuration file "$@" not found!'
 693         @echo >&2 '***'
 694         @echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
 695         @echo >&2 '*** "make menuconfig" or "make xconfig").'
 696         @echo >&2 '***'
 697         @/bin/false
 698
 699 # The actual configuration files used during the build are stored in
 700 # include/generated/ and include/config/. Update them if .config is newer than
 701 # include/config/auto.conf (which mirrors .config).
 702 #
 703 # This exploits the 'multi-target pattern rule' trick.
 704 # The syncconfig should be executed only once to make all the targets.
 705 # (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
 706 %/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h: $(KCONFIG_CONFIG)
 707         $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
 708 else # !may-sync-config
 709 # External modules and some install targets need include/generated/autoconf.h
 710 # and include/config/auto.conf but do not care if they are up-to-date.
 711 # Use auto.conf to trigger the test
 712 PHONY += include/config/auto.conf
 713
 714 include/config/auto.conf:
 715         $(Q)test -e include/generated/autoconf.h -a -e $@ || (          \
 716         echo >&2;                                                       \
 717         echo >&2 "  ERROR: Kernel configuration is invalid.";           \
 718         echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
 719         echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";      \
 720         echo >&2 ;                                                      \
 721         /bin/false)
 722
 723 endif # may-sync-config
 724 endif # need-config
 725
 726 KBUILD_CFLAGS   += $(call cc-option,-fno-delete-null-pointer-checks,)
 727 KBUILD_CFLAGS   += $(call cc-disable-warning,frame-address,)
 728 KBUILD_CFLAGS   += $(call cc-disable-warning, format-truncation)
 729 KBUILD_CFLAGS   += $(call cc-disable-warning, format-overflow)
 730 KBUILD_CFLAGS   += $(call cc-disable-warning, address-of-packed-member)
 731
 732 ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
 733 KBUILD_CFLAGS += -O2
 734 else ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3
 735 KBUILD_CFLAGS += -O3
 736 else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
 737 KBUILD_CFLAGS += -Os
 738 endif
 739
 740 # Tell gcc to never replace conditional load with a non-conditional one
 741 KBUILD_CFLAGS   += $(call cc-option,--param=allow-store-data-races=0)
 742 KBUILD_CFLAGS   += $(call cc-option,-fno-allow-store-data-races)
 743
 744 include scripts/Makefile.kcov
 745 include scripts/Makefile.gcc-plugins
 746
 747 ifdef CONFIG_READABLE_ASM
 748 # Disable optimizations that make assembler listings hard to read.
 749 # reorder blocks reorders the control in the function
 750 # ipa clone creates specialized cloned functions
 751 # partial inlining inlines only parts of functions
 752 KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
 753                  $(call cc-option,-fno-ipa-cp-clone,) \
 754                  $(call cc-option,-fno-partial-inlining)
 755 endif
 756
 757 ifneq ($(CONFIG_FRAME_WARN),0)
 758 KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
 759 endif
 760
 761 stackp-flags-$(CONFIG_CC_HAS_STACKPROTECTOR_NONE) := -fno-stack-protector
 762 stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
 763 stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
 764
 765 KBUILD_CFLAGS += $(stackp-flags-y)
 766
 767 ifdef CONFIG_CC_IS_CLANG
 768 KBUILD_CPPFLAGS += -Qunused-arguments
 769 KBUILD_CFLAGS += -Wno-format-invalid-specifier
 770 KBUILD_CFLAGS += -Wno-gnu
 771 # CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
 772 # source of a reference will be _MergedGlobals and not on of the whitelisted names.
 773 # See modpost pattern 2
 774 KBUILD_CFLAGS += -mno-global-merge
 775 else
 776
 777 # These warnings generated too much noise in a regular build.
 778 # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
 779 KBUILD_CFLAGS += -Wno-unused-but-set-variable
 780
 781 # Warn about unmarked fall-throughs in switch statement.
 782 # Disabled for clang while comment to attribute conversion happens and
 783 # https://github.com/ClangBuiltLinux/linux/issues/636 is discussed.
 784 KBUILD_CFLAGS += $(call cc-option,-Wimplicit-fallthrough,)
 785 endif
 786
 787 KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
 788 ifdef CONFIG_FRAME_POINTER
 789 KBUILD_CFLAGS   += -fno-omit-frame-pointer -fno-optimize-sibling-calls
 790 else
 791 # Some targets (ARM with Thumb2, for example), can't be built with frame
 792 # pointers.  For those, we don't have FUNCTION_TRACER automatically
 793 # select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
 794 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
 795 # -fomit-frame-pointer with FUNCTION_TRACER.
 796 ifndef CONFIG_FUNCTION_TRACER
 797 KBUILD_CFLAGS   += -fomit-frame-pointer
 798 endif
 799 endif
 800
 801 # Initialize all stack variables with a pattern, if desired.
 802 ifdef CONFIG_INIT_STACK_ALL
 803 KBUILD_CFLAGS   += -ftrivial-auto-var-init=pattern
 804 endif
 805
 806 DEBUG_CFLAGS    := $(call cc-option, -fno-var-tracking-assignments)
 807
 808 ifdef CONFIG_DEBUG_INFO
 809 ifdef CONFIG_DEBUG_INFO_SPLIT
 810 DEBUG_CFLAGS    += -gsplit-dwarf
 811 else
 812 DEBUG_CFLAGS    += -g
 813 endif
 814 KBUILD_AFLAGS   += -Wa,-gdwarf-2
 815 endif
 816 ifdef CONFIG_DEBUG_INFO_DWARF4
 817 DEBUG_CFLAGS    += -gdwarf-4
 818 endif
 819
 820 ifdef CONFIG_DEBUG_INFO_REDUCED
 821 DEBUG_CFLAGS    += $(call cc-option, -femit-struct-debug-baseonly) \
 822                    $(call cc-option,-fno-var-tracking)
 823 endif
 824
 825 KBUILD_CFLAGS += $(DEBUG_CFLAGS)
 826 export DEBUG_CFLAGS
 827
 828 ifdef CONFIG_FUNCTION_TRACER
 829 ifdef CONFIG_FTRACE_MCOUNT_RECORD
 830   # gcc 5 supports generating the mcount tables directly
 831   ifeq ($(call cc-option-yn,-mrecord-mcount),y)
 832     CC_FLAGS_FTRACE     += -mrecord-mcount
 833     export CC_USING_RECORD_MCOUNT := 1
 834   endif
 835   ifdef CONFIG_HAVE_NOP_MCOUNT
 836     ifeq ($(call cc-option-yn, -mnop-mcount),y)
 837       CC_FLAGS_FTRACE   += -mnop-mcount
 838       CC_FLAGS_USING    += -DCC_USING_NOP_MCOUNT
 839     endif
 840   endif
 841 endif
 842 ifdef CONFIG_HAVE_FENTRY
 843   ifeq ($(call cc-option-yn, -mfentry),y)
 844     CC_FLAGS_FTRACE     += -mfentry
 845     CC_FLAGS_USING      += -DCC_USING_FENTRY
 846   endif
 847 endif
 848 export CC_FLAGS_FTRACE
 849 KBUILD_CFLAGS   += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
 850 KBUILD_AFLAGS   += $(CC_FLAGS_USING)
 851 ifdef CONFIG_DYNAMIC_FTRACE
 852         ifdef CONFIG_HAVE_C_RECORDMCOUNT
 853                 BUILD_C_RECORDMCOUNT := y
 854                 export BUILD_C_RECORDMCOUNT
 855         endif
 856 endif
 857 endif
 858
 859 # We trigger additional mismatches with less inlining
 860 ifdef CONFIG_DEBUG_SECTION_MISMATCH
 861 KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
 862 endif
 863
 864 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
 865 KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
 866 LDFLAGS_vmlinux += --gc-sections
 867 endif
 868
 869 ifdef CONFIG_LIVEPATCH
 870 KBUILD_CFLAGS += $(call cc-option, -flive-patching=inline-clone)
 871 endif
 872
 873 # arch Makefile may override CC so keep this after arch Makefile is included
 874 NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
 875
 876 # warn about C99 declaration after statement
 877 KBUILD_CFLAGS += -Wdeclaration-after-statement
 878
 879 # Variable Length Arrays (VLAs) should not be used anywhere in the kernel
 880 KBUILD_CFLAGS += -Wvla
 881
 882 # disable pointer signed / unsigned warnings in gcc 4.0
 883 KBUILD_CFLAGS += -Wno-pointer-sign
 884
 885 # disable stringop warnings in gcc 8+
 886 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
 887
 888 # We'll want to enable this eventually, but it's not going away for 5.7 at least
 889 KBUILD_CFLAGS += $(call cc-disable-warning, zero-length-bounds)
 890 KBUILD_CFLAGS += $(call cc-disable-warning, array-bounds)
 891 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
 892
 893 # Another good warning that we'll want to enable eventually
 894 KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
 895
 896 # Enabled with W=2, disabled by default as noisy
 897 KBUILD_CFLAGS += $(call cc-disable-warning, maybe-uninitialized)
 898
 899 # disable invalid "can't wrap" optimizations for signed / pointers
 900 KBUILD_CFLAGS   += $(call cc-option,-fno-strict-overflow)
 901
 902 # clang sets -fmerge-all-constants by default as optimization, but this
 903 # is non-conforming behavior for C and in fact breaks the kernel, so we
 904 # need to disable it here generally.
 905 KBUILD_CFLAGS   += $(call cc-option,-fno-merge-all-constants)
 906
 907 # for gcc -fno-merge-all-constants disables everything, but it is fine
 908 # to have actual conforming behavior enabled.
 909 KBUILD_CFLAGS   += $(call cc-option,-fmerge-constants)
 910
 911 # Make sure -fstack-check isn't enabled (like gentoo apparently did)
 912 KBUILD_CFLAGS  += $(call cc-option,-fno-stack-check,)
 913
 914 # conserve stack if available
 915 KBUILD_CFLAGS   += $(call cc-option,-fconserve-stack)
 916
 917 # Prohibit date/time macros, which would make the build non-deterministic
 918 KBUILD_CFLAGS   += $(call cc-option,-Werror=date-time)
 919
 920 # enforce correct pointer usage
 921 KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)
 922
 923 # Require designated initializers for all marked structures
 924 KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)
 925
 926 # change __FILE__ to the relative path from the srctree
 927 KBUILD_CFLAGS   += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
 928
 929 # ensure -fcf-protection is disabled when using retpoline as it is
 930 # incompatible with -mindirect-branch=thunk-extern
 931 ifdef CONFIG_RETPOLINE
 932 KBUILD_CFLAGS += $(call cc-option,-fcf-protection=none)
 933 endif
 934
 935 include scripts/Makefile.kasan
 936 include scripts/Makefile.extrawarn
 937 include scripts/Makefile.ubsan
 938
 939 # Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
 940 KBUILD_CPPFLAGS += $(KCPPFLAGS)
 941 KBUILD_AFLAGS   += $(KAFLAGS)
 942 KBUILD_CFLAGS   += $(KCFLAGS)
 943
 944 KBUILD_LDFLAGS_MODULE += --build-id
 945 LDFLAGS_vmlinux += --build-id
 946
 947 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
 948 LDFLAGS_vmlinux += $(call ld-option, -X,)
 949 endif
 950
 951 ifeq ($(CONFIG_RELR),y)
 952 LDFLAGS_vmlinux += --pack-dyn-relocs=relr
 953 endif
 954
 955 # Align the bit size of userspace programs with the kernel
 956 KBUILD_USERCFLAGS  += $(filter -m32 -m64, $(KBUILD_CFLAGS))
 957 KBUILD_USERLDFLAGS += $(filter -m32 -m64, $(KBUILD_CFLAGS))
 958
 959 # make the checker run with the right architecture
 960 CHECKFLAGS += --arch=$(ARCH)
 961
 962 # insure the checker run with the right endianness
 963 CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
 964
 965 # the checker needs the correct machine size
 966 CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
 967
 968 # Default kernel image to build when no specific target is given.
 969 # KBUILD_IMAGE may be overruled on the command line or
 970 # set in the environment
 971 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
 972 # this default value
 973 export KBUILD_IMAGE ?= vmlinux
 974
 975 #
 976 # INSTALL_PATH specifies where to place the updated kernel and system map
 977 # images. Default is /boot, but you can set it to other values
 978 export  INSTALL_PATH ?= /boot
 979
 980 #
 981 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
 982 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
 983 # an argument if needed. Otherwise it defaults to the kernel install path
 984 #
 985 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
 986
 987 #
 988 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
 989 # relocations required by build roots.  This is not defined in the
 990 # makefile but the argument can be passed to make if needed.
 991 #
 992
 993 MODLIB  = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
 994 export MODLIB
 995
 996 #
 997 # INSTALL_MOD_STRIP, if defined, will cause modules to be
 998 # stripped after they are installed.  If INSTALL_MOD_STRIP is '1', then
 999 # the default option --strip-debug will be used.  Otherwise,
1000 # INSTALL_MOD_STRIP value will be used as the options to the strip command.
1001
1002 ifdef INSTALL_MOD_STRIP
1003 ifeq ($(INSTALL_MOD_STRIP),1)
1004 mod_strip_cmd = $(STRIP) --strip-debug
1005 else
1006 mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
1007 endif # INSTALL_MOD_STRIP=1
1008 else
1009 mod_strip_cmd = true
1010 endif # INSTALL_MOD_STRIP
1011 export mod_strip_cmd
1012
1013 # CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
1014 # after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
1015 # or CONFIG_MODULE_COMPRESS_XZ.
1016
1017 mod_compress_cmd = true
1018 ifdef CONFIG_MODULE_COMPRESS
1019   ifdef CONFIG_MODULE_COMPRESS_GZIP
1020     mod_compress_cmd = gzip -n -f
1021   endif # CONFIG_MODULE_COMPRESS_GZIP
1022   ifdef CONFIG_MODULE_COMPRESS_XZ
1023     mod_compress_cmd = xz -f
1024   endif # CONFIG_MODULE_COMPRESS_XZ
1025 endif # CONFIG_MODULE_COMPRESS
1026 export mod_compress_cmd
1027
1028 ifdef CONFIG_MODULE_SIG_ALL
1029 $(eval $(call config_filename,MODULE_SIG_KEY))
1030
1031 mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
1032 else
1033 mod_sign_cmd = true
1034 endif
1035 export mod_sign_cmd
1036
1037 HOST_LIBELF_LIBS = $(shell pkg-config libelf --libs 2>/dev/null || echo -lelf)
1038
1039 ifdef CONFIG_STACK_VALIDATION
1040   has_libelf := $(call try-run,\
1041                 echo "int main() {}" | $(HOSTCC) -xc -o /dev/null $(HOST_LIBELF_LIBS) -,1,0)
1042   ifeq ($(has_libelf),1)
1043     objtool_target := tools/objtool FORCE
1044   else
1045     SKIP_STACK_VALIDATION := 1
1046     export SKIP_STACK_VALIDATION
1047   endif
1048 endif
1049
1050 PHONY += prepare0
1051
1052 export MODORDER := $(extmod-prefix)modules.order
1053 export MODULES_NSDEPS := $(extmod-prefix)modules.nsdeps
1054
1055 ifeq ($(KBUILD_EXTMOD),)
1056 core-y          += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
1057
1058 vmlinux-dirs    := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
1059                      $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
1060                      $(net-y) $(net-m) $(libs-y) $(libs-m) $(virt-y)))
1061
1062 vmlinux-alldirs := $(sort $(vmlinux-dirs) Documentation \
1063                      $(patsubst %/,%,$(filter %/, $(init-) $(core-) \
1064                         $(drivers-) $(net-) $(libs-) $(virt-))))
1065
1066 build-dirs      := $(vmlinux-dirs)
1067 clean-dirs      := $(vmlinux-alldirs)
1068
1069 init-y          := $(patsubst %/, %/built-in.a, $(init-y))
1070 core-y          := $(patsubst %/, %/built-in.a, $(core-y))
1071 drivers-y       := $(patsubst %/, %/built-in.a, $(drivers-y))
1072 net-y           := $(patsubst %/, %/built-in.a, $(net-y))
1073 libs-y2         := $(patsubst %/, %/built-in.a, $(filter %/, $(libs-y)))
1074 ifdef CONFIG_MODULES
1075 libs-y1         := $(filter-out %/, $(libs-y))
1076 libs-y2         += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1077 else
1078 libs-y1         := $(patsubst %/, %/lib.a, $(libs-y))
1079 endif
1080 virt-y          := $(patsubst %/, %/built-in.a, $(virt-y))
1081
1082 # Externally visible symbols (used by link-vmlinux.sh)
1083 export KBUILD_VMLINUX_OBJS := $(head-y) $(init-y) $(core-y) $(libs-y2) \
1084                               $(drivers-y) $(net-y) $(virt-y)
1085 export KBUILD_VMLINUX_LIBS := $(libs-y1)
1086 export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1087 export LDFLAGS_vmlinux
1088 # used by scripts/Makefile.package
1089 export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) LICENSES arch include scripts tools)
1090
1091 vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
1092
1093 # Recurse until adjust_autoksyms.sh is satisfied
1094 PHONY += autoksyms_recursive
1095 ifdef CONFIG_TRIM_UNUSED_KSYMS
1096 autoksyms_recursive: descend modules.order
1097         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1098           "$(MAKE) -f $(srctree)/Makefile vmlinux"
1099 endif
1100
1101 # For the kernel to actually contain only the needed exported symbols,
1102 # we have to build modules as well to determine what those symbols are.
1103 # (this can be evaluated only once include/config/auto.conf has been included)
1104 ifdef CONFIG_TRIM_UNUSED_KSYMS
1105   KBUILD_MODULES := 1
1106 endif
1107
1108 autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1109
1110 quiet_cmd_autoksyms_h = GEN     $@
1111       cmd_autoksyms_h = mkdir -p $(dir $@); \
1112                         $(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@
1113
1114 $(autoksyms_h):
1115         $(call cmd,autoksyms_h)
1116
1117 ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1118
1119 # Final link of vmlinux with optional arch pass after final link
1120 cmd_link-vmlinux =                                                 \
1121         $(CONFIG_SHELL) $< $(LD) $(KBUILD_LDFLAGS) $(LDFLAGS_vmlinux) ;    \
1122         $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1123
1124 vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1125         +$(call if_changed,link-vmlinux)
1126
1127 targets := vmlinux
1128
1129 # The actual objects are generated when descending,
1130 # make sure no implicit rule kicks in
1131 $(sort $(vmlinux-deps)): descend ;
1132
1133 filechk_kernel.release = \
1134         echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1135
1136 # Store (new) KERNELRELEASE string in include/config/kernel.release
1137 include/config/kernel.release: FORCE
1138         $(call filechk,kernel.release)
1139
1140 # Additional helpers built in scripts/
1141 # Carefully list dependencies so we do not try to build scripts twice
1142 # in parallel
1143 PHONY += scripts
1144 scripts: scripts_basic scripts_dtc
1145         $(Q)$(MAKE) $(build)=$(@)
1146
1147 # Things we need to do before we recursively start building the kernel
1148 # or the modules are listed in "prepare".
1149 # A multi level approach is used. prepareN is processed before prepareN-1.
1150 # archprepare is used in arch Makefiles and when processed asm symlink,
1151 # version.h and scripts_basic is processed / created.
1152
1153 PHONY += prepare archprepare
1154
1155 archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1156         asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h \
1157         include/generated/autoconf.h
1158
1159 prepare0: archprepare
1160         $(Q)$(MAKE) $(build)=scripts/mod
1161         $(Q)$(MAKE) $(build)=.
1162
1163 # All the preparing..
1164 prepare: prepare0 prepare-objtool
1165
1166 # Support for using generic headers in asm-generic
1167 asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1168
1169 PHONY += asm-generic uapi-asm-generic
1170 asm-generic: uapi-asm-generic
1171         $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1172         generic=include/asm-generic
1173 uapi-asm-generic:
1174         $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1175         generic=include/uapi/asm-generic
1176
1177 PHONY += prepare-objtool
1178 prepare-objtool: $(objtool_target)
1179 ifeq ($(SKIP_STACK_VALIDATION),1)
1180 ifdef CONFIG_UNWINDER_ORC
1181         @echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1182         @false
1183 else
1184         @echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1185 endif
1186 endif
1187
1188 # Generate some files
1189 # ---------------------------------------------------------------------------
1190
1191 # KERNELRELEASE can change from a few different places, meaning version.h
1192 # needs to be updated, so this check is forced on all builds
1193
1194 uts_len := 64
1195 define filechk_utsrelease.h
1196         if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1197           echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1198           exit 1;                                                         \
1199         fi;                                                               \
1200         echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1201 endef
1202
1203 define filechk_version.h
1204         echo \#define LINUX_VERSION_CODE $(shell                         \
1205         expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1206         echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))'
1207 endef
1208
1209 $(version_h): FORCE
1210         $(call filechk,version.h)
1211         $(Q)rm -f $(old_version_h)
1212
1213 include/generated/utsrelease.h: include/config/kernel.release FORCE
1214         $(call filechk,utsrelease.h)
1215
1216 PHONY += headerdep
1217 headerdep:
1218         $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1219         $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1220
1221 # ---------------------------------------------------------------------------
1222 # Kernel headers
1223
1224 #Default location for installed headers
1225 export INSTALL_HDR_PATH = $(objtree)/usr
1226
1227 quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1228       cmd_headers_install = \
1229         mkdir -p $(INSTALL_HDR_PATH); \
1230         rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1231         usr/include $(INSTALL_HDR_PATH)
1232
1233 PHONY += headers_install
1234 headers_install: headers
1235         $(call cmd,headers_install)
1236
1237 PHONY += archheaders archscripts
1238
1239 hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1240
1241 PHONY += headers
1242 headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1243         $(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1244           $(error Headers not exportable for the $(SRCARCH) architecture))
1245         $(Q)$(MAKE) $(hdr-inst)=include/uapi
1246         $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1247
1248 # Deprecated. It is no-op now.
1249 PHONY += headers_check
1250 headers_check:
1251         @:
1252
1253 ifdef CONFIG_HEADERS_INSTALL
1254 prepare: headers
1255 endif
1256
1257 PHONY += scripts_unifdef
1258 scripts_unifdef: scripts_basic
1259         $(Q)$(MAKE) $(build)=scripts scripts/unifdef
1260
1261 # ---------------------------------------------------------------------------
1262 # Kernel selftest
1263
1264 PHONY += kselftest
1265 kselftest:
1266         $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1267
1268 kselftest-%: FORCE
1269         $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1270
1271 PHONY += kselftest-merge
1272 kselftest-merge:
1273         $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1274         $(Q)find $(srctree)/tools/testing/selftests -name config | \
1275                 xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1276         $(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1277
1278 # ---------------------------------------------------------------------------
1279 # Devicetree files
1280
1281 ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1282 dtstree := arch/$(SRCARCH)/boot/dts
1283 endif
1284
1285 ifneq ($(dtstree),)
1286
1287 %.dtb: include/config/kernel.release scripts_dtc
1288         $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1289
1290 PHONY += dtbs dtbs_install dtbs_check
1291 dtbs: include/config/kernel.release scripts_dtc
1292         $(Q)$(MAKE) $(build)=$(dtstree)
1293
1294 ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1295 export CHECK_DTBS=y
1296 dtbs: dt_binding_check
1297 endif
1298
1299 dtbs_check: dtbs
1300
1301 dtbs_install:
1302         $(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1303
1304 ifdef CONFIG_OF_EARLY_FLATTREE
1305 all: dtbs
1306 endif
1307
1308 endif
1309
1310 PHONY += scripts_dtc
1311 scripts_dtc: scripts_basic
1312         $(Q)$(MAKE) $(build)=scripts/dtc
1313
1314 ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1315 export CHECK_DT_BINDING=y
1316 endif
1317
1318 PHONY += dt_binding_check
1319 dt_binding_check: scripts_dtc
1320         $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1321
1322 # ---------------------------------------------------------------------------
1323 # Modules
1324
1325 ifdef CONFIG_MODULES
1326
1327 # By default, build modules as well
1328
1329 all: modules
1330
1331 # Build modules
1332 #
1333 # A module can be listed more than once in obj-m resulting in
1334 # duplicate lines in modules.order files.  Those are removed
1335 # using awk while concatenating to the final file.
1336
1337 PHONY += modules
1338 modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_check
1339         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1340
1341 PHONY += modules_check
1342 modules_check: modules.order
1343         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1344
1345 modules.order: descend
1346         $(Q)$(AWK) '!x[$$0]++' $(addsuffix /$@, $(build-dirs)) > $@
1347
1348 # Target to prepare building external modules
1349 PHONY += modules_prepare
1350 modules_prepare: prepare
1351
1352 # Target to install modules
1353 PHONY += modules_install
1354 modules_install: _modinst_ _modinst_post
1355
1356 PHONY += _modinst_
1357 _modinst_:
1358         @rm -rf $(MODLIB)/kernel
1359         @rm -f $(MODLIB)/source
1360         @mkdir -p $(MODLIB)/kernel
1361         @ln -s $(abspath $(srctree)) $(MODLIB)/source
1362         @if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
1363                 rm -f $(MODLIB)/build ; \
1364                 ln -s $(CURDIR) $(MODLIB)/build ; \
1365         fi
1366         @sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order
1367         @cp -f modules.builtin $(MODLIB)/
1368         @cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
1369         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1370
1371 # This depmod is only for convenience to give the initial
1372 # boot a modules.dep even before / is mounted read-write.  However the
1373 # boot script depmod is the master version.
1374 PHONY += _modinst_post
1375 _modinst_post: _modinst_
1376         $(call cmd,depmod)
1377
1378 ifeq ($(CONFIG_MODULE_SIG), y)
1379 PHONY += modules_sign
1380 modules_sign:
1381         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1382 endif
1383
1384 else # CONFIG_MODULES
1385
1386 # Modules not configured
1387 # ---------------------------------------------------------------------------
1388
1389 PHONY += modules modules_install
1390 modules modules_install:
1391         @echo >&2
1392         @echo >&2 "The present kernel configuration has modules disabled."
1393         @echo >&2 "Type 'make config' and enable loadable module support."
1394         @echo >&2 "Then build a kernel with module support enabled."
1395         @echo >&2
1396         @exit 1
1397
1398 endif # CONFIG_MODULES
1399
1400 ###
1401 # Cleaning is done on three levels.
1402 # make clean     Delete most generated files
1403 #                Leave enough to build external modules
1404 # make mrproper  Delete the current configuration, and all generated files
1405 # make distclean Remove editor backup files, patch leftover files and the like
1406
1407 # Directories & files removed with 'make clean'
1408 CLEAN_FILES += include/ksym \
1409                modules.builtin modules.builtin.modinfo modules.nsdeps
1410
1411 # Directories & files removed with 'make mrproper'
1412 MRPROPER_FILES += include/config include/generated          \
1413                   arch/$(SRCARCH)/include/generated .tmp_objdiff \
1414                   debian snap tar-install \
1415                   .config .config.old .version \
1416                   Module.symvers \
1417                   signing_key.pem signing_key.priv signing_key.x509     \
1418                   x509.genkey extra_certificates signing_key.x509.keyid \
1419                   signing_key.x509.signer vmlinux-gdb.py \
1420                   *.spec
1421
1422 # Directories & files removed with 'make distclean'
1423 DISTCLEAN_FILES += tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS
1424
1425 # clean - Delete most, but leave enough to build external modules
1426 #
1427 clean: rm-files := $(CLEAN_FILES)
1428
1429 PHONY += archclean vmlinuxclean
1430
1431 vmlinuxclean:
1432         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1433         $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1434
1435 clean: archclean vmlinuxclean
1436
1437 # mrproper - Delete all generated files, including .config
1438 #
1439 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1440 mrproper-dirs      := $(addprefix _mrproper_,scripts)
1441
1442 PHONY += $(mrproper-dirs) mrproper
1443 $(mrproper-dirs):
1444         $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1445
1446 mrproper: clean $(mrproper-dirs)
1447         $(call cmd,rmfiles)
1448
1449 # distclean
1450 #
1451 distclean: rm-files := $(wildcard $(DISTCLEAN_FILES))
1452
1453 PHONY += distclean
1454
1455 distclean: mrproper
1456         $(call cmd,rmfiles)
1457         @find $(srctree) $(RCS_FIND_IGNORE) \
1458                 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1459                 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1460                 -o -name 'core' \) \
1461                 -type f -print | xargs rm -f
1462
1463
1464 # Packaging of the kernel to various formats
1465 # ---------------------------------------------------------------------------
1466
1467 %src-pkg: FORCE
1468         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1469 %pkg: include/config/kernel.release FORCE
1470         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1471
1472 # Brief documentation of the typical targets used
1473 # ---------------------------------------------------------------------------
1474
1475 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1476 boards := $(sort $(notdir $(boards)))
1477 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1478 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1479
1480 PHONY += help
1481 help:
1482         @echo  'Cleaning targets:'
1483         @echo  '  clean           - Remove most generated files but keep the config and'
1484         @echo  '                    enough build support to build external modules'
1485         @echo  '  mrproper        - Remove all generated files + config + various backup files'
1486         @echo  '  distclean       - mrproper + remove editor backup and patch files'
1487         @echo  ''
1488         @echo  'Configuration targets:'
1489         @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1490         @echo  ''
1491         @echo  'Other generic targets:'
1492         @echo  '  all             - Build all targets marked with [*]'
1493         @echo  '* vmlinux         - Build the bare kernel'
1494         @echo  '* modules         - Build all modules'
1495         @echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1496         @echo  '  dir/            - Build all files in dir and below'
1497         @echo  '  dir/file.[ois]  - Build specified target only'
1498         @echo  '  dir/file.ll     - Build the LLVM assembly file'
1499         @echo  '                    (requires compiler support for LLVM assembly generation)'
1500         @echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1501         @echo  '                    (requires a recent binutils and recent build (System.map))'
1502         @echo  '  dir/file.ko     - Build module including final link'
1503         @echo  '  modules_prepare - Set up for building external modules'
1504         @echo  '  tags/TAGS       - Generate tags file for editors'
1505         @echo  '  cscope          - Generate cscope index'
1506         @echo  '  gtags           - Generate GNU GLOBAL index'
1507         @echo  '  kernelrelease   - Output the release version string (use with make -s)'
1508         @echo  '  kernelversion   - Output the version stored in Makefile (use with make -s)'
1509         @echo  '  image_name      - Output the image name (use with make -s)'
1510         @echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1511          echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1512          echo  ''
1513         @echo  'Static analysers:'
1514         @echo  '  checkstack      - Generate a list of stack hogs'
1515         @echo  '  namespacecheck  - Name space analysis on compiled kernel'
1516         @echo  '  versioncheck    - Sanity check on version.h usage'
1517         @echo  '  includecheck    - Check for duplicate included header files'
1518         @echo  '  export_report   - List the usages of all exported symbols'
1519         @echo  '  headerdep       - Detect inclusion cycles in headers'
1520         @echo  '  coccicheck      - Check with Coccinelle'
1521         @echo  ''
1522         @echo  'Tools:'
1523         @echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1524         @echo  ''
1525         @echo  'Kernel selftest:'
1526         @echo  '  kselftest         - Build and run kernel selftest'
1527         @echo  '                      Build, install, and boot kernel before'
1528         @echo  '                      running kselftest on it'
1529         @echo  '                      Run as root for full coverage'
1530         @echo  '  kselftest-all     - Build kernel selftest'
1531         @echo  '  kselftest-install - Build and install kernel selftest'
1532         @echo  '  kselftest-clean   - Remove all generated kselftest files'
1533         @echo  '  kselftest-merge   - Merge all the config dependencies of'
1534         @echo  '                      kselftest to existing .config.'
1535         @echo  ''
1536         @$(if $(dtstree), \
1537                 echo 'Devicetree:'; \
1538                 echo '* dtbs             - Build device tree blobs for enabled boards'; \
1539                 echo '  dtbs_install     - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1540                 echo '  dt_binding_check - Validate device tree binding documents'; \
1541                 echo '  dtbs_check       - Validate device tree source files';\
1542                 echo '')
1543
1544         @echo 'Userspace tools targets:'
1545         @echo '  use "make tools/help"'
1546         @echo '  or  "cd tools; make help"'
1547         @echo  ''
1548         @echo  'Kernel packaging:'
1549         @$(MAKE) -f $(srctree)/scripts/Makefile.package help
1550         @echo  ''
1551         @echo  'Documentation targets:'
1552         @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1553         @echo  ''
1554         @echo  'Architecture specific targets ($(SRCARCH)):'
1555         @$(if $(archhelp),$(archhelp),\
1556                 echo '  No architecture specific help defined for $(SRCARCH)')
1557         @echo  ''
1558         @$(if $(boards), \
1559                 $(foreach b, $(boards), \
1560                 printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1561                 echo '')
1562         @$(if $(board-dirs), \
1563                 $(foreach b, $(board-dirs), \
1564                 printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1565                 printf "  %-16s - Show all of the above\\n" help-boards; \
1566                 echo '')
1567
1568         @echo  '  make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1569         @echo  '  make V=2   [targets] 2 => give reason for rebuild of target'
1570         @echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1571         @echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1572         @echo  '                       (sparse by default)'
1573         @echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1574         @echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1575         @echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
1576         @echo  '                1: warnings which may be relevant and do not occur too often'
1577         @echo  '                2: warnings which occur quite often but may still be relevant'
1578         @echo  '                3: more obscure warnings, can most likely be ignored'
1579         @echo  '                Multiple levels can be combined with W=12 or W=123'
1580         @echo  ''
1581         @echo  'Execute "make" or "make all" to build all targets marked with [*] '
1582         @echo  'For further info see the ./README file'
1583
1584
1585 help-board-dirs := $(addprefix help-,$(board-dirs))
1586
1587 help-boards: $(help-board-dirs)
1588
1589 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1590
1591 $(help-board-dirs): help-%:
1592         @echo  'Architecture specific targets ($(SRCARCH) $*):'
1593         @$(if $(boards-per-dir), \
1594                 $(foreach b, $(boards-per-dir), \
1595                 printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1596                 echo '')
1597
1598
1599 # Documentation targets
1600 # ---------------------------------------------------------------------------
1601 DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1602                linkcheckdocs dochelp refcheckdocs
1603 PHONY += $(DOC_TARGETS)
1604 $(DOC_TARGETS):
1605         $(Q)$(MAKE) $(build)=Documentation $@
1606
1607 # Misc
1608 # ---------------------------------------------------------------------------
1609
1610 PHONY += scripts_gdb
1611 scripts_gdb: prepare0
1612         $(Q)$(MAKE) $(build)=scripts/gdb
1613         $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1614
1615 ifdef CONFIG_GDB_SCRIPTS
1616 all: scripts_gdb
1617 endif
1618
1619 else # KBUILD_EXTMOD
1620
1621 ###
1622 # External module support.
1623 # When building external modules the kernel used as basis is considered
1624 # read-only, and no consistency checks are made and the make
1625 # system is not used on the basis kernel. If updates are required
1626 # in the basis kernel ordinary make commands (without M=...) must
1627 # be used.
1628 #
1629 # The following are the only valid targets when building external
1630 # modules.
1631 # make M=dir clean     Delete all automatically generated files
1632 # make M=dir modules   Make all modules in specified dir
1633 # make M=dir           Same as 'make M=dir modules'
1634 # make M=dir modules_install
1635 #                      Install the modules built in the module directory
1636 #                      Assumes install directory is already created
1637
1638 # We are always building modules
1639 KBUILD_MODULES := 1
1640
1641 PHONY += $(objtree)/Module.symvers
1642 $(objtree)/Module.symvers:
1643         @test -e $(objtree)/Module.symvers || ( \
1644         echo; \
1645         echo "  WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1646         echo "           is missing; modules will have no dependencies and modversions."; \
1647         echo )
1648
1649 build-dirs := $(KBUILD_EXTMOD)
1650 PHONY += modules
1651 modules: descend $(objtree)/Module.symvers
1652         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1653
1654 PHONY += modules_install
1655 modules_install: _emodinst_ _emodinst_post
1656
1657 install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1658 PHONY += _emodinst_
1659 _emodinst_:
1660         $(Q)mkdir -p $(MODLIB)/$(install-dir)
1661         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1662
1663 PHONY += _emodinst_post
1664 _emodinst_post: _emodinst_
1665         $(call cmd,depmod)
1666
1667 clean-dirs := $(KBUILD_EXTMOD)
1668 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps
1669
1670 PHONY += help
1671 help:
1672         @echo  '  Building external modules.'
1673         @echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1674         @echo  ''
1675         @echo  '  modules         - default target, build the module(s)'
1676         @echo  '  modules_install - install the module'
1677         @echo  '  clean           - remove generated files in module directory only'
1678         @echo  ''
1679
1680 PHONY += prepare
1681 endif # KBUILD_EXTMOD
1682
1683 # Single targets
1684 # ---------------------------------------------------------------------------
1685 # To build individual files in subdirectories, you can do like this:
1686 #
1687 #   make foo/bar/baz.s
1688 #
1689 # The supported suffixes for single-target are listed in 'single-targets'
1690 #
1691 # To build only under specific subdirectories, you can do like this:
1692 #
1693 #   make foo/bar/baz/
1694
1695 ifdef single-build
1696
1697 # .ko is special because modpost is needed
1698 single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1699 single-no-ko := $(sort $(patsubst %.ko,%.mod, $(MAKECMDGOALS)))
1700
1701 $(single-ko): single_modpost
1702         @:
1703 $(single-no-ko): descend
1704         @:
1705
1706 ifeq ($(KBUILD_EXTMOD),)
1707 # For the single build of in-tree modules, use a temporary file to avoid
1708 # the situation of modules_install installing an invalid modules.order.
1709 MODORDER := .modules.tmp
1710 endif
1711
1712 PHONY += single_modpost
1713 single_modpost: $(single-no-ko)
1714         $(Q){ $(foreach m, $(single-ko), echo $(extmod-prefix)$m;) } > $(MODORDER)
1715         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1716
1717 KBUILD_MODULES := 1
1718
1719 export KBUILD_SINGLE_TARGETS := $(addprefix $(extmod-prefix), $(single-no-ko))
1720
1721 # trim unrelated directories
1722 build-dirs := $(foreach d, $(build-dirs), \
1723                         $(if $(filter $(d)/%, $(KBUILD_SINGLE_TARGETS)), $(d)))
1724
1725 endif
1726
1727 # Handle descending into subdirectories listed in $(build-dirs)
1728 # Preset locale variables to speed up the build process. Limit locale
1729 # tweaks to this spot to avoid wrong language settings when running
1730 # make menuconfig etc.
1731 # Error messages still appears in the original language
1732 PHONY += descend $(build-dirs)
1733 descend: $(build-dirs)
1734 $(build-dirs): prepare
1735         $(Q)$(MAKE) $(build)=$@ \
1736         single-build=$(if $(filter-out $@/, $(filter $@/%, $(single-no-ko))),1) \
1737         need-builtin=1 need-modorder=1
1738
1739 clean-dirs := $(addprefix _clean_, $(clean-dirs))
1740 PHONY += $(clean-dirs) clean
1741 $(clean-dirs):
1742         $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1743
1744 clean: $(clean-dirs)
1745         $(call cmd,rmfiles)
1746         @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1747                 \( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1748                 -o -name '*.ko.*' \
1749                 -o -name '*.dtb' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1750                 -o -name '*.dwo' -o -name '*.lst' \
1751                 -o -name '*.su' -o -name '*.mod' \
1752                 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1753                 -o -name '*.lex.c' -o -name '*.tab.[ch]' \
1754                 -o -name '*.asn1.[ch]' \
1755                 -o -name '*.symtypes' -o -name 'modules.order' \
1756                 -o -name '.tmp_*.o.*' \
1757                 -o -name '*.c.[012]*.*' \
1758                 -o -name '*.ll' \
1759                 -o -name '*.gcno' \) -type f -print | xargs rm -f
1760
1761 # Generate tags for editors
1762 # ---------------------------------------------------------------------------
1763 quiet_cmd_tags = GEN     $@
1764       cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1765
1766 tags TAGS cscope gtags: FORCE
1767         $(call cmd,tags)
1768
1769 # Script to generate missing namespace dependencies
1770 # ---------------------------------------------------------------------------
1771
1772 PHONY += nsdeps
1773 nsdeps: export KBUILD_NSDEPS=1
1774 nsdeps: modules
1775         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1776
1777 # Scripts to check various things for consistency
1778 # ---------------------------------------------------------------------------
1779
1780 PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1781
1782 includecheck:
1783         find $(srctree)/* $(RCS_FIND_IGNORE) \
1784                 -name '*.[hcS]' -type f -print | sort \
1785                 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1786
1787 versioncheck:
1788         find $(srctree)/* $(RCS_FIND_IGNORE) \
1789                 -name '*.[hcS]' -type f -print | sort \
1790                 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1791
1792 coccicheck:
1793         $(Q)$(BASH) $(srctree)/scripts/$@
1794
1795 namespacecheck:
1796         $(PERL) $(srctree)/scripts/namespace.pl
1797
1798 export_report:
1799         $(PERL) $(srctree)/scripts/export_report.pl
1800
1801 PHONY += checkstack kernelrelease kernelversion image_name
1802
1803 # UML needs a little special treatment here.  It wants to use the host
1804 # toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
1805 # else wants $(ARCH), including people doing cross-builds, which means
1806 # that $(SUBARCH) doesn't work here.
1807 ifeq ($(ARCH), um)
1808 CHECKSTACK_ARCH := $(SUBARCH)
1809 else
1810 CHECKSTACK_ARCH := $(ARCH)
1811 endif
1812 checkstack:
1813         $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1814         $(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1815
1816 kernelrelease:
1817         @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1818
1819 kernelversion:
1820         @echo $(KERNELVERSION)
1821
1822 image_name:
1823         @echo $(KBUILD_IMAGE)
1824
1825 # Clear a bunch of variables before executing the submake
1826
1827 ifeq ($(quiet),silent_)
1828 tools_silent=s
1829 endif
1830
1831 tools/: FORCE
1832         $(Q)mkdir -p $(objtree)/tools
1833         $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1834
1835 tools/%: FORCE
1836         $(Q)mkdir -p $(objtree)/tools
1837         $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1838
1839 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
1840       cmd_rmfiles = rm -rf $(rm-files)
1841
1842 # Run depmod only if we have System.map and depmod is executable
1843 quiet_cmd_depmod = DEPMOD  $(KERNELRELEASE)
1844       cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1845                    $(KERNELRELEASE)
1846
1847 # read saved command lines for existing targets
1848 existing-targets := $(wildcard $(sort $(targets)))
1849
1850 -include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
1851
1852 endif # config-build
1853 endif # mixed-build
1854 endif # need-sub-make
1855
1856 PHONY += FORCE
1857 FORCE:
1858
1859 # Declare the contents of the PHONY variable as phony.  We keep that
1860 # information in a variable so we can use it in if_changed and friends.
1861 .PHONY: $(PHONY)