Makefile

   1 # SPDX-License-Identifier: GPL-2.0
   2 VERSION = 5
   3 PATCHLEVEL = 10
   4 SUBLEVEL = 4
   5 EXTRAVERSION =
   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 = $(C)
 210 endif
 211 ifndef KBUILD_CHECKSRC
 212   KBUILD_CHECKSRC = 0
 213 endif
 214
 215 # Call message checker as part of the C compilation
 216 #
 217 # Use 'make D=1' to enable checking
 218 # Use 'make D=2' to create the message catalog
 219
 220 ifdef D
 221   ifeq ("$(origin D)", "command line")
 222     KBUILD_KMSG_CHECK = $(D)
 223   endif
 224 endif
 225 ifndef KBUILD_KMSG_CHECK
 226   KBUILD_KMSG_CHECK = 0
 227 endif
 228
 229 # Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
 230 # directory of external module to build. Setting M= takes precedence.
 231 ifeq ("$(origin M)", "command line")
 232   KBUILD_EXTMOD := $(M)
 233 endif
 234
 235 $(if $(word 2, $(KBUILD_EXTMOD)), \
 236         $(error building multiple external modules is not supported))
 237
 238 export KBUILD_CHECKSRC KBUILD_EXTMOD
 239
 240 extmod-prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
 241
 242 ifeq ($(abs_srctree),$(abs_objtree))
 243         # building in the source tree
 244         srctree := .
 245         building_out_of_srctree :=
 246 else
 247         ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
 248                 # building in a subdirectory of the source tree
 249                 srctree := ..
 250         else
 251                 srctree := $(abs_srctree)
 252         endif
 253         building_out_of_srctree := 1
 254 endif
 255
 256 ifneq ($(KBUILD_ABS_SRCTREE),)
 257 srctree := $(abs_srctree)
 258 endif
 259
 260 objtree         := .
 261 VPATH           := $(srctree)
 262
 263 export building_out_of_srctree srctree objtree VPATH
 264
 265 # To make sure we do not include .config for any of the *config targets
 266 # catch them early, and hand them over to scripts/kconfig/Makefile
 267 # It is allowed to specify more targets when calling make, including
 268 # mixing *config targets and build targets.
 269 # For example 'make oldconfig all'.
 270 # Detect when mixed targets is specified, and make a second invocation
 271 # of make so .config is not included in this case either (for *config).
 272
 273 version_h := include/generated/uapi/linux/version.h
 274 old_version_h := include/linux/version.h
 275
 276 clean-targets := %clean mrproper cleandocs
 277 no-dot-config-targets := $(clean-targets) \
 278                          cscope gtags TAGS tags help% %docs check% coccicheck \
 279                          $(version_h) headers headers_% archheaders archscripts \
 280                          %asm-generic kernelversion %src-pkg dt_binding_check \
 281                          outputmakefile
 282 no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease
 283 single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
 284
 285 config-build    :=
 286 mixed-build     :=
 287 need-config     := 1
 288 may-sync-config := 1
 289 single-build    :=
 290
 291 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
 292         ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
 293                 need-config :=
 294         endif
 295 endif
 296
 297 ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
 298         ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
 299                 may-sync-config :=
 300         endif
 301 endif
 302
 303 ifneq ($(KBUILD_EXTMOD),)
 304         may-sync-config :=
 305 endif
 306
 307 ifeq ($(KBUILD_EXTMOD),)
 308         ifneq ($(filter %config,$(MAKECMDGOALS)),)
 309                 config-build := 1
 310                 ifneq ($(words $(MAKECMDGOALS)),1)
 311                         mixed-build := 1
 312                 endif
 313         endif
 314 endif
 315
 316 # We cannot build single targets and the others at the same time
 317 ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
 318         single-build := 1
 319         ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
 320                 mixed-build := 1
 321         endif
 322 endif
 323
 324 # For "make -j clean all", "make -j mrproper defconfig all", etc.
 325 ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
 326         ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
 327                 mixed-build := 1
 328         endif
 329 endif
 330
 331 # install and modules_install need also be processed one by one
 332 ifneq ($(filter install,$(MAKECMDGOALS)),)
 333         ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
 334                 mixed-build := 1
 335         endif
 336 endif
 337
 338 ifdef mixed-build
 339 # ===========================================================================
 340 # We're called with mixed targets (*config and build targets).
 341 # Handle them one by one.
 342
 343 PHONY += $(MAKECMDGOALS) __build_one_by_one
 344
 345 $(MAKECMDGOALS): __build_one_by_one
 346         @:
 347
 348 __build_one_by_one:
 349         $(Q)set -e; \
 350         for i in $(MAKECMDGOALS); do \
 351                 $(MAKE) -f $(srctree)/Makefile $$i; \
 352         done
 353
 354 else # !mixed-build
 355
 356 include scripts/Kbuild.include
 357
 358 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
 359 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
 360 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
 361 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
 362
 363 include scripts/subarch.include
 364
 365 # Cross compiling and selecting different set of gcc/bin-utils
 366 # ---------------------------------------------------------------------------
 367 #
 368 # When performing cross compilation for other architectures ARCH shall be set
 369 # to the target architecture. (See arch/* for the possibilities).
 370 # ARCH can be set during invocation of make:
 371 # make ARCH=ia64
 372 # Another way is to have ARCH set in the environment.
 373 # The default ARCH is the host where make is executed.
 374
 375 # CROSS_COMPILE specify the prefix used for all executables used
 376 # during compilation. Only gcc and related bin-utils executables
 377 # are prefixed with $(CROSS_COMPILE).
 378 # CROSS_COMPILE can be set on the command line
 379 # make CROSS_COMPILE=ia64-linux-
 380 # Alternatively CROSS_COMPILE can be set in the environment.
 381 # Default value for CROSS_COMPILE is not to prefix executables
 382 # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
 383 ARCH            ?= $(SUBARCH)
 384
 385 # Architecture as present in compile.h
 386 UTS_MACHINE     := $(ARCH)
 387 SRCARCH         := $(ARCH)
 388
 389 # Additional ARCH settings for x86
 390 ifeq ($(ARCH),i386)
 391         SRCARCH := x86
 392 endif
 393 ifeq ($(ARCH),x86_64)
 394         SRCARCH := x86
 395 endif
 396
 397 # Additional ARCH settings for sparc
 398 ifeq ($(ARCH),sparc32)
 399        SRCARCH := sparc
 400 endif
 401 ifeq ($(ARCH),sparc64)
 402        SRCARCH := sparc
 403 endif
 404
 405 # Additional ARCH settings for sh
 406 ifeq ($(ARCH),sh64)
 407        SRCARCH := sh
 408 endif
 409
 410 KCONFIG_CONFIG  ?= .config
 411 export KCONFIG_CONFIG
 412
 413 # Default file for 'make defconfig'. This may be overridden by arch-Makefile.
 414 export KBUILD_DEFCONFIG := defconfig
 415
 416 # SHELL used by kbuild
 417 CONFIG_SHELL := sh
 418
 419 HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
 420 HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
 421 HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
 422
 423 ifneq ($(LLVM),)
 424 HOSTCC  = clang
 425 HOSTCXX = clang++
 426 else
 427 HOSTCC  = gcc
 428 HOSTCXX = g++
 429 endif
 430
 431 export KBUILD_USERCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
 432                               -O2 -fomit-frame-pointer -std=gnu89
 433 export KBUILD_USERLDFLAGS :=
 434
 435 KBUILD_HOSTCFLAGS   := $(KBUILD_USERCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
 436 KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
 437 KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
 438 KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
 439
 440 # Make variables (CC, etc...)
 441 CPP             = $(CC) -E
 442 ifneq ($(LLVM),)
 443 CC              = clang
 444 LD              = ld.lld
 445 AR              = llvm-ar
 446 NM              = llvm-nm
 447 OBJCOPY         = llvm-objcopy
 448 OBJDUMP         = llvm-objdump
 449 READELF         = llvm-readelf
 450 STRIP           = llvm-strip
 451 else
 452 CC              = $(CROSS_COMPILE)gcc
 453 LD              = $(CROSS_COMPILE)ld
 454 AR              = $(CROSS_COMPILE)ar
 455 NM              = $(CROSS_COMPILE)nm
 456 OBJCOPY         = $(CROSS_COMPILE)objcopy
 457 OBJDUMP         = $(CROSS_COMPILE)objdump
 458 READELF         = $(CROSS_COMPILE)readelf
 459 STRIP           = $(CROSS_COMPILE)strip
 460 endif
 461 PAHOLE          = pahole
 462 RESOLVE_BTFIDS  = $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
 463 LEX             = flex
 464 YACC            = bison
 465 AWK             = awk
 466 INSTALLKERNEL  := installkernel
 467 DEPMOD          = /sbin/depmod
 468 PERL            = perl
 469 PYTHON          = python
 470 PYTHON3         = python3
 471 CHECK           = sparse
 472 BASH            = bash
 473 KGZIP           = gzip
 474 KBZIP2          = bzip2
 475 KLZOP           = lzop
 476 LZMA            = lzma
 477 LZ4             = lz4c
 478 XZ              = xz
 479 ZSTD            = zstd
 480
 481 CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
 482                   -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
 483 KMSG_CHECK      = $(srctree)/scripts/kmsg-doc
 484 NOSTDINC_FLAGS :=
 485 CFLAGS_MODULE   =
 486 AFLAGS_MODULE   =
 487 LDFLAGS_MODULE  =
 488 CFLAGS_KERNEL   =
 489 AFLAGS_KERNEL   =
 490 LDFLAGS_vmlinux =
 491
 492 # Prefer linux-backports-modules
 493 ifneq ($(KBUILD_SRC),)
 494 ifneq ($(shell if test -e $(KBUILD_OUTPUT)/ubuntu-build; then echo yes; fi),yes)
 495 UBUNTUINCLUDE := -I/usr/src/linux-headers-lbm-$(KERNELRELEASE)
 496 endif
 497 endif
 498
 499 # Use USERINCLUDE when you must reference the UAPI directories only.
 500 USERINCLUDE    := \
 501                 -I$(srctree)/arch/$(SRCARCH)/include/uapi \
 502                 -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
 503                 -I$(srctree)/include/uapi \
 504                 -I$(objtree)/include/generated/uapi \
 505                 -include $(srctree)/include/linux/kconfig.h
 506
 507 # Use LINUXINCLUDE when you must reference the include/ directory.
 508 # Needed to be compatible with the O= option
 509 LINUXINCLUDE    := \
 510                 $(UBUNTUINCLUDE) \
 511                 -I$(srctree)/arch/$(SRCARCH)/include \
 512                 -I$(objtree)/arch/$(SRCARCH)/include/generated \
 513                 $(if $(building_out_of_srctree),-I$(srctree)/include) \
 514                 -I$(objtree)/include \
 515                 $(USERINCLUDE)
 516
 517 # UBUNTU: Include our third party driver stuff too
 518 LINUXINCLUDE   += -Iubuntu/include $(if $(KBUILD_SRC),-I$(srctree)/ubuntu/include)
 519
 520 KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
 521 KBUILD_CFLAGS   := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
 522                    -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
 523                    -Werror=implicit-function-declaration -Werror=implicit-int \
 524                    -Werror=return-type -Wno-format-security \
 525                    -std=gnu89
 526 KBUILD_CPPFLAGS := -D__KERNEL__
 527 KBUILD_AFLAGS_KERNEL :=
 528 KBUILD_CFLAGS_KERNEL :=
 529 KBUILD_AFLAGS_MODULE  := -DMODULE
 530 KBUILD_CFLAGS_MODULE  := -DMODULE
 531 KBUILD_LDFLAGS_MODULE :=
 532 KBUILD_LDFLAGS :=
 533 CLANG_FLAGS :=
 534
 535 export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC
 536 export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
 537 export PERL PYTHON PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
 538 export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
 539 export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
 540
 541 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
 542 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
 543 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
 544 export KBUILD_KMSG_CHECK KMSG_CHECK
 545 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
 546 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
 547
 548 # Files to ignore in find ... statements
 549
 550 export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
 551                           -name CVS -o -name .pc -o -name .hg -o -name .git \) \
 552                           -prune -o
 553 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
 554                          --exclude CVS --exclude .pc --exclude .hg --exclude .git
 555
 556 # ===========================================================================
 557 # Rules shared between *config targets and build targets
 558
 559 # Basic helpers built in scripts/basic/
 560 PHONY += scripts_basic
 561 scripts_basic:
 562         $(Q)$(MAKE) $(build)=scripts/basic
 563         $(Q)rm -f .tmp_quiet_recordmcount
 564
 565 PHONY += outputmakefile
 566 # Before starting out-of-tree build, make sure the source tree is clean.
 567 # outputmakefile generates a Makefile in the output directory, if using a
 568 # separate output directory. This allows convenient use of make in the
 569 # output directory.
 570 # At the same time when output Makefile generated, generate .gitignore to
 571 # ignore whole output directory
 572 outputmakefile:
 573 ifdef building_out_of_srctree
 574         $(Q)if [ -f $(srctree)/.config -o \
 575                  -d $(srctree)/include/config -o \
 576                  -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
 577                 echo >&2 "***"; \
 578                 echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
 579                 echo >&2 "*** in $(abs_srctree)";\
 580                 echo >&2 "***"; \
 581                 false; \
 582         fi
 583         $(Q)ln -fsn $(srctree) source
 584         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile $(srctree)
 585         $(Q)test -e .gitignore || \
 586         { echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
 587 endif
 588
 589 ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),)
 590 ifneq ($(CROSS_COMPILE),)
 591 CLANG_FLAGS     += --target=$(notdir $(CROSS_COMPILE:%-=%))
 592 GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
 593 CLANG_FLAGS     += --prefix=$(GCC_TOOLCHAIN_DIR)$(notdir $(CROSS_COMPILE))
 594 GCC_TOOLCHAIN   := $(realpath $(GCC_TOOLCHAIN_DIR)/..)
 595 endif
 596 ifneq ($(GCC_TOOLCHAIN),)
 597 CLANG_FLAGS     += --gcc-toolchain=$(GCC_TOOLCHAIN)
 598 endif
 599 ifneq ($(LLVM_IAS),1)
 600 CLANG_FLAGS     += -no-integrated-as
 601 endif
 602 CLANG_FLAGS     += -Werror=unknown-warning-option
 603 KBUILD_CFLAGS   += $(CLANG_FLAGS)
 604 KBUILD_AFLAGS   += $(CLANG_FLAGS)
 605 export CLANG_FLAGS
 606 endif
 607
 608 # The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
 609 # Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
 610 # CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
 611 # and from include/config/auto.conf.cmd to detect the compiler upgrade.
 612 CC_VERSION_TEXT = $(shell $(CC) --version 2>/dev/null | head -n 1)
 613
 614 ifdef config-build
 615 # ===========================================================================
 616 # *config targets only - make sure prerequisites are updated, and descend
 617 # in scripts/kconfig to make the *config target
 618
 619 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
 620 # KBUILD_DEFCONFIG may point out an alternative default configuration
 621 # used for 'make defconfig'
 622 include arch/$(SRCARCH)/Makefile
 623 export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
 624
 625 config: outputmakefile scripts_basic FORCE
 626         $(Q)$(MAKE) $(build)=scripts/kconfig $@
 627
 628 %config: outputmakefile scripts_basic FORCE
 629         $(Q)$(MAKE) $(build)=scripts/kconfig $@
 630
 631 else #!config-build
 632 # ===========================================================================
 633 # Build targets only - this includes vmlinux, arch specific targets, clean
 634 # targets and others. In general all targets except *config targets.
 635
 636 # If building an external module we do not care about the all: rule
 637 # but instead __all depend on modules
 638 PHONY += all
 639 ifeq ($(KBUILD_EXTMOD),)
 640 __all: all
 641 else
 642 __all: modules
 643 endif
 644
 645 # Decide whether to build built-in, modular, or both.
 646 # Normally, just do built-in.
 647
 648 KBUILD_MODULES :=
 649 KBUILD_BUILTIN := 1
 650
 651 # If we have only "make modules", don't compile built-in objects.
 652 ifeq ($(MAKECMDGOALS),modules)
 653   KBUILD_BUILTIN :=
 654 endif
 655
 656 # If we have "make <whatever> modules", compile modules
 657 # in addition to whatever we do anyway.
 658 # Just "make" or "make all" shall build modules as well
 659
 660 ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
 661   KBUILD_MODULES := 1
 662 endif
 663
 664 ifeq ($(MAKECMDGOALS),)
 665   KBUILD_MODULES := 1
 666 endif
 667
 668 export KBUILD_MODULES KBUILD_BUILTIN
 669
 670 ifdef need-config
 671 include include/config/auto.conf
 672 endif
 673
 674 ifeq ($(KBUILD_EXTMOD),)
 675 # Objects we will link into vmlinux / subdirs we need to visit
 676 core-y          := init/ usr/
 677 drivers-y       := drivers/ sound/ ubuntu/
 678 drivers-$(CONFIG_SAMPLES) += samples/
 679 drivers-y       += net/ virt/
 680 libs-y          := lib/
 681 endif # KBUILD_EXTMOD
 682
 683 # The all: target is the default when no target is given on the
 684 # command line.
 685 # This allow a user to issue only 'make' to build a kernel including modules
 686 # Defaults to vmlinux, but the arch makefile usually adds further targets
 687 all: vmlinux
 688
 689 CFLAGS_GCOV     := -fprofile-arcs -ftest-coverage \
 690         $(call cc-option,-fno-tree-loop-im) \
 691         $(call cc-disable-warning,maybe-uninitialized,)
 692 export CFLAGS_GCOV
 693
 694 # The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
 695 ifdef CONFIG_FUNCTION_TRACER
 696   CC_FLAGS_FTRACE := -pg
 697 endif
 698
 699 RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
 700 RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
 701 RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
 702 RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
 703 RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
 704 RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
 705 export RETPOLINE_CFLAGS
 706 export RETPOLINE_VDSO_CFLAGS
 707
 708 include arch/$(SRCARCH)/Makefile
 709
 710 ifdef need-config
 711 ifdef may-sync-config
 712 # Read in dependencies to all Kconfig* files, make sure to run syncconfig if
 713 # changes are detected. This should be included after arch/$(SRCARCH)/Makefile
 714 # because some architectures define CROSS_COMPILE there.
 715 include include/config/auto.conf.cmd
 716
 717 $(KCONFIG_CONFIG):
 718         @echo >&2 '***'
 719         @echo >&2 '*** Configuration file "$@" not found!'
 720         @echo >&2 '***'
 721         @echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
 722         @echo >&2 '*** "make menuconfig" or "make xconfig").'
 723         @echo >&2 '***'
 724         @/bin/false
 725
 726 # The actual configuration files used during the build are stored in
 727 # include/generated/ and include/config/. Update them if .config is newer than
 728 # include/config/auto.conf (which mirrors .config).
 729 #
 730 # This exploits the 'multi-target pattern rule' trick.
 731 # The syncconfig should be executed only once to make all the targets.
 732 # (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
 733 quiet_cmd_syncconfig = SYNC    $@
 734       cmd_syncconfig = $(MAKE) -f $(srctree)/Makefile syncconfig
 735
 736 %/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h: $(KCONFIG_CONFIG)
 737         +$(call cmd,syncconfig)
 738 else # !may-sync-config
 739 # External modules and some install targets need include/generated/autoconf.h
 740 # and include/config/auto.conf but do not care if they are up-to-date.
 741 # Use auto.conf to trigger the test
 742 PHONY += include/config/auto.conf
 743
 744 include/config/auto.conf:
 745         $(Q)test -e include/generated/autoconf.h -a -e $@ || (          \
 746         echo >&2;                                                       \
 747         echo >&2 "  ERROR: Kernel configuration is invalid.";           \
 748         echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
 749         echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";      \
 750         echo >&2 ;                                                      \
 751         /bin/false)
 752
 753 endif # may-sync-config
 754 endif # need-config
 755
 756 KBUILD_CFLAGS   += $(call cc-option,-fno-delete-null-pointer-checks,)
 757 KBUILD_CFLAGS   += $(call cc-disable-warning,frame-address,)
 758 KBUILD_CFLAGS   += $(call cc-disable-warning, format-truncation)
 759 KBUILD_CFLAGS   += $(call cc-disable-warning, format-overflow)
 760 KBUILD_CFLAGS   += $(call cc-disable-warning, address-of-packed-member)
 761
 762 ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
 763 KBUILD_CFLAGS += -O2
 764 else ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3
 765 KBUILD_CFLAGS += -O3
 766 else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
 767 KBUILD_CFLAGS += -Os
 768 endif
 769
 770 # Tell gcc to never replace conditional load with a non-conditional one
 771 KBUILD_CFLAGS   += $(call cc-option,--param=allow-store-data-races=0)
 772 KBUILD_CFLAGS   += $(call cc-option,-fno-allow-store-data-races)
 773
 774 ifdef CONFIG_READABLE_ASM
 775 # Disable optimizations that make assembler listings hard to read.
 776 # reorder blocks reorders the control in the function
 777 # ipa clone creates specialized cloned functions
 778 # partial inlining inlines only parts of functions
 779 KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
 780                  $(call cc-option,-fno-ipa-cp-clone,) \
 781                  $(call cc-option,-fno-partial-inlining)
 782 endif
 783
 784 ifneq ($(CONFIG_FRAME_WARN),0)
 785 KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
 786 endif
 787
 788 stackp-flags-y                                    := -fno-stack-protector
 789 stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
 790 stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
 791
 792 KBUILD_CFLAGS += $(stackp-flags-y)
 793
 794 ifdef CONFIG_CC_IS_CLANG
 795 KBUILD_CPPFLAGS += -Qunused-arguments
 796 KBUILD_CFLAGS += -Wno-format-invalid-specifier
 797 KBUILD_CFLAGS += -Wno-gnu
 798 # CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
 799 # source of a reference will be _MergedGlobals and not on of the whitelisted names.
 800 # See modpost pattern 2
 801 KBUILD_CFLAGS += -mno-global-merge
 802 else
 803
 804 # These warnings generated too much noise in a regular build.
 805 # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
 806 KBUILD_CFLAGS += -Wno-unused-but-set-variable
 807
 808 # Warn about unmarked fall-throughs in switch statement.
 809 # Disabled for clang while comment to attribute conversion happens and
 810 # https://github.com/ClangBuiltLinux/linux/issues/636 is discussed.
 811 KBUILD_CFLAGS += $(call cc-option,-Wimplicit-fallthrough,)
 812 endif
 813
 814 KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
 815 ifdef CONFIG_FRAME_POINTER
 816 KBUILD_CFLAGS   += -fno-omit-frame-pointer -fno-optimize-sibling-calls
 817 else
 818 # Some targets (ARM with Thumb2, for example), can't be built with frame
 819 # pointers.  For those, we don't have FUNCTION_TRACER automatically
 820 # select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
 821 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
 822 # -fomit-frame-pointer with FUNCTION_TRACER.
 823 ifndef CONFIG_FUNCTION_TRACER
 824 KBUILD_CFLAGS   += -fomit-frame-pointer
 825 endif
 826 endif
 827
 828 # Initialize all stack variables with a 0xAA pattern.
 829 ifdef CONFIG_INIT_STACK_ALL_PATTERN
 830 KBUILD_CFLAGS   += -ftrivial-auto-var-init=pattern
 831 endif
 832
 833 # Initialize all stack variables with a zero value.
 834 ifdef CONFIG_INIT_STACK_ALL_ZERO
 835 # Future support for zero initialization is still being debated, see
 836 # https://bugs.llvm.org/show_bug.cgi?id=45497. These flags are subject to being
 837 # renamed or dropped.
 838 KBUILD_CFLAGS   += -ftrivial-auto-var-init=zero
 839 KBUILD_CFLAGS   += -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
 840 endif
 841
 842 # Workaround for GCC versions < 5.0
 843 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61801
 844 ifdef CONFIG_CC_IS_GCC
 845 DEBUG_CFLAGS    := $(call cc-ifversion, -lt, 0500, $(call cc-option, -fno-var-tracking-assignments))
 846 endif
 847
 848 ifdef CONFIG_DEBUG_INFO
 849
 850 ifdef CONFIG_DEBUG_INFO_SPLIT
 851 DEBUG_CFLAGS    += -gsplit-dwarf
 852 else
 853 DEBUG_CFLAGS    += -g
 854 endif
 855
 856 ifneq ($(LLVM_IAS),1)
 857 KBUILD_AFLAGS   += -Wa,-gdwarf-2
 858 endif
 859
 860 ifdef CONFIG_DEBUG_INFO_DWARF4
 861 DEBUG_CFLAGS    += -gdwarf-4
 862 endif
 863
 864 ifdef CONFIG_DEBUG_INFO_REDUCED
 865 DEBUG_CFLAGS    += $(call cc-option, -femit-struct-debug-baseonly) \
 866                    $(call cc-option,-fno-var-tracking)
 867 endif
 868
 869 ifdef CONFIG_DEBUG_INFO_COMPRESSED
 870 DEBUG_CFLAGS    += -gz=zlib
 871 KBUILD_AFLAGS   += -gz=zlib
 872 KBUILD_LDFLAGS  += --compress-debug-sections=zlib
 873 endif
 874
 875 endif # CONFIG_DEBUG_INFO
 876
 877 KBUILD_CFLAGS += $(DEBUG_CFLAGS)
 878 export DEBUG_CFLAGS
 879
 880 ifdef CONFIG_FUNCTION_TRACER
 881 ifdef CONFIG_FTRACE_MCOUNT_RECORD
 882   # gcc 5 supports generating the mcount tables directly
 883   ifeq ($(call cc-option-yn,-mrecord-mcount),y)
 884     CC_FLAGS_FTRACE     += -mrecord-mcount
 885     export CC_USING_RECORD_MCOUNT := 1
 886   endif
 887   ifdef CONFIG_HAVE_NOP_MCOUNT
 888     ifeq ($(call cc-option-yn, -mnop-mcount),y)
 889       CC_FLAGS_FTRACE   += -mnop-mcount
 890       CC_FLAGS_USING    += -DCC_USING_NOP_MCOUNT
 891     endif
 892   endif
 893 endif
 894 ifdef CONFIG_HAVE_FENTRY
 895   ifeq ($(call cc-option-yn, -mfentry),y)
 896     CC_FLAGS_FTRACE     += -mfentry
 897     CC_FLAGS_USING      += -DCC_USING_FENTRY
 898   endif
 899 endif
 900 export CC_FLAGS_FTRACE
 901 KBUILD_CFLAGS   += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
 902 KBUILD_AFLAGS   += $(CC_FLAGS_USING)
 903 ifdef CONFIG_DYNAMIC_FTRACE
 904         ifdef CONFIG_HAVE_C_RECORDMCOUNT
 905                 BUILD_C_RECORDMCOUNT := y
 906                 export BUILD_C_RECORDMCOUNT
 907         endif
 908 endif
 909 endif
 910
 911 # We trigger additional mismatches with less inlining
 912 ifdef CONFIG_DEBUG_SECTION_MISMATCH
 913 KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
 914 endif
 915
 916 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
 917 KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
 918 LDFLAGS_vmlinux += --gc-sections
 919 endif
 920
 921 ifdef CONFIG_SHADOW_CALL_STACK
 922 CC_FLAGS_SCS    := -fsanitize=shadow-call-stack
 923 KBUILD_CFLAGS   += $(CC_FLAGS_SCS)
 924 export CC_FLAGS_SCS
 925 endif
 926
 927 ifdef CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_32B
 928 KBUILD_CFLAGS += -falign-functions=32
 929 endif
 930
 931 # arch Makefile may override CC so keep this after arch Makefile is included
 932 NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
 933
 934 # warn about C99 declaration after statement
 935 KBUILD_CFLAGS += -Wdeclaration-after-statement
 936
 937 # Variable Length Arrays (VLAs) should not be used anywhere in the kernel
 938 KBUILD_CFLAGS += -Wvla
 939
 940 # disable pointer signed / unsigned warnings in gcc 4.0
 941 KBUILD_CFLAGS += -Wno-pointer-sign
 942
 943 # disable stringop warnings in gcc 8+
 944 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
 945
 946 # We'll want to enable this eventually, but it's not going away for 5.7 at least
 947 KBUILD_CFLAGS += $(call cc-disable-warning, zero-length-bounds)
 948 KBUILD_CFLAGS += $(call cc-disable-warning, array-bounds)
 949 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
 950
 951 # Another good warning that we'll want to enable eventually
 952 KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
 953
 954 # Enabled with W=2, disabled by default as noisy
 955 KBUILD_CFLAGS += $(call cc-disable-warning, maybe-uninitialized)
 956
 957 # disable invalid "can't wrap" optimizations for signed / pointers
 958 KBUILD_CFLAGS   += -fno-strict-overflow
 959
 960 # Make sure -fstack-check isn't enabled (like gentoo apparently did)
 961 KBUILD_CFLAGS  += -fno-stack-check
 962
 963 # conserve stack if available
 964 KBUILD_CFLAGS   += $(call cc-option,-fconserve-stack)
 965
 966 # Prohibit date/time macros, which would make the build non-deterministic
 967 KBUILD_CFLAGS   += -Werror=date-time
 968
 969 # enforce correct pointer usage
 970 KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)
 971
 972 # Require designated initializers for all marked structures
 973 KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)
 974
 975 # change __FILE__ to the relative path from the srctree
 976 KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
 977
 978 # ensure -fcf-protection is disabled when using retpoline as it is
 979 # incompatible with -mindirect-branch=thunk-extern
 980 ifdef CONFIG_RETPOLINE
 981 KBUILD_CFLAGS += $(call cc-option,-fcf-protection=none)
 982 endif
 983
 984 # include additional Makefiles when needed
 985 include-y                       := scripts/Makefile.extrawarn
 986 include-$(CONFIG_KASAN)         += scripts/Makefile.kasan
 987 include-$(CONFIG_KCSAN)         += scripts/Makefile.kcsan
 988 include-$(CONFIG_UBSAN)         += scripts/Makefile.ubsan
 989 include-$(CONFIG_KCOV)          += scripts/Makefile.kcov
 990 include-$(CONFIG_GCC_PLUGINS)   += scripts/Makefile.gcc-plugins
 991
 992 include $(addprefix $(srctree)/, $(include-y))
 993
 994 # scripts/Makefile.gcc-plugins is intentionally included last.
 995 # Do not add $(call cc-option,...) below this line. When you build the kernel
 996 # from the clean source tree, the GCC plugins do not exist at this point.
 997
 998 # Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
 999 KBUILD_CPPFLAGS += $(KCPPFLAGS)
1000 KBUILD_AFLAGS   += $(KAFLAGS)
1001 KBUILD_CFLAGS   += $(KCFLAGS)
1002
1003 KBUILD_LDFLAGS_MODULE += --build-id=sha1
1004 LDFLAGS_vmlinux += --build-id=sha1
1005
1006 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1007 LDFLAGS_vmlinux += $(call ld-option, -X,)
1008 endif
1009
1010 ifeq ($(CONFIG_RELR),y)
1011 LDFLAGS_vmlinux += --pack-dyn-relocs=relr
1012 endif
1013
1014 # We never want expected sections to be placed heuristically by the
1015 # linker. All sections should be explicitly named in the linker script.
1016 ifdef CONFIG_LD_ORPHAN_WARN
1017 LDFLAGS_vmlinux += --orphan-handling=warn
1018 endif
1019
1020 # Align the bit size of userspace programs with the kernel
1021 KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1022 KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1023
1024 # make the checker run with the right architecture
1025 CHECKFLAGS += --arch=$(ARCH)
1026
1027 # insure the checker run with the right endianness
1028 CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1029
1030 # the checker needs the correct machine size
1031 CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1032
1033 # Default kernel image to build when no specific target is given.
1034 # KBUILD_IMAGE may be overruled on the command line or
1035 # set in the environment
1036 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
1037 # this default value
1038 export KBUILD_IMAGE ?= vmlinux
1039
1040 #
1041 # INSTALL_PATH specifies where to place the updated kernel and system map
1042 # images. Default is /boot, but you can set it to other values
1043 export  INSTALL_PATH ?= /boot
1044
1045 #
1046 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1047 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1048 # an argument if needed. Otherwise it defaults to the kernel install path
1049 #
1050 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1051
1052 #
1053 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1054 # relocations required by build roots.  This is not defined in the
1055 # makefile but the argument can be passed to make if needed.
1056 #
1057
1058 MODLIB  = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1059 export MODLIB
1060
1061 #
1062 # INSTALL_MOD_STRIP, if defined, will cause modules to be
1063 # stripped after they are installed.  If INSTALL_MOD_STRIP is '1', then
1064 # the default option --strip-debug will be used.  Otherwise,
1065 # INSTALL_MOD_STRIP value will be used as the options to the strip command.
1066
1067 ifdef INSTALL_MOD_STRIP
1068 ifeq ($(INSTALL_MOD_STRIP),1)
1069 mod_strip_cmd = $(STRIP) --strip-debug
1070 else
1071 mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
1072 endif # INSTALL_MOD_STRIP=1
1073 else
1074 mod_strip_cmd = true
1075 endif # INSTALL_MOD_STRIP
1076 export mod_strip_cmd
1077
1078 # CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
1079 # after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
1080 # or CONFIG_MODULE_COMPRESS_XZ.
1081
1082 mod_compress_cmd = true
1083 ifdef CONFIG_MODULE_COMPRESS
1084   ifdef CONFIG_MODULE_COMPRESS_GZIP
1085     mod_compress_cmd = $(KGZIP) -n -f
1086   endif # CONFIG_MODULE_COMPRESS_GZIP
1087   ifdef CONFIG_MODULE_COMPRESS_XZ
1088     mod_compress_cmd = $(XZ) -f
1089   endif # CONFIG_MODULE_COMPRESS_XZ
1090 endif # CONFIG_MODULE_COMPRESS
1091 export mod_compress_cmd
1092
1093 ifdef CONFIG_MODULE_SIG_ALL
1094 $(eval $(call config_filename,MODULE_SIG_KEY))
1095
1096 mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
1097 else
1098 mod_sign_cmd = true
1099 endif
1100 export mod_sign_cmd
1101
1102 HOST_LIBELF_LIBS = $(shell pkg-config libelf --libs 2>/dev/null || echo -lelf)
1103
1104 has_libelf = $(call try-run,\
1105                echo "int main() {}" | $(HOSTCC) -xc -o /dev/null $(HOST_LIBELF_LIBS) -,1,0)
1106
1107 ifdef CONFIG_STACK_VALIDATION
1108   ifeq ($(has_libelf),1)
1109     objtool_target := tools/objtool FORCE
1110   else
1111     SKIP_STACK_VALIDATION := 1
1112     export SKIP_STACK_VALIDATION
1113   endif
1114 endif
1115
1116 ifdef CONFIG_BPF
1117 ifdef CONFIG_DEBUG_INFO_BTF
1118   ifeq ($(has_libelf),1)
1119     resolve_btfids_target := tools/bpf/resolve_btfids FORCE
1120   else
1121     ERROR_RESOLVE_BTFIDS := 1
1122   endif
1123 endif # CONFIG_DEBUG_INFO_BTF
1124 endif # CONFIG_BPF
1125
1126 PHONY += prepare0
1127
1128 export MODORDER := $(extmod-prefix)modules.order
1129 export MODULES_NSDEPS := $(extmod-prefix)modules.nsdeps
1130
1131 ifeq ($(KBUILD_EXTMOD),)
1132 core-y          += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
1133
1134 vmlinux-dirs    := $(patsubst %/,%,$(filter %/, \
1135                      $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
1136                      $(libs-y) $(libs-m)))
1137
1138 vmlinux-alldirs := $(sort $(vmlinux-dirs) Documentation \
1139                      $(patsubst %/,%,$(filter %/, $(core-) \
1140                         $(drivers-) $(libs-))))
1141
1142 subdir-modorder := $(addsuffix modules.order,$(filter %/, \
1143                         $(core-y) $(core-m) $(libs-y) $(libs-m) \
1144                         $(drivers-y) $(drivers-m)))
1145
1146 build-dirs      := $(vmlinux-dirs)
1147 clean-dirs      := $(vmlinux-alldirs)
1148
1149 # Externally visible symbols (used by link-vmlinux.sh)
1150 KBUILD_VMLINUX_OBJS := $(head-y) $(patsubst %/,%/built-in.a, $(core-y))
1151 KBUILD_VMLINUX_OBJS += $(addsuffix built-in.a, $(filter %/, $(libs-y)))
1152 ifdef CONFIG_MODULES
1153 KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1154 KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1155 else
1156 KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1157 endif
1158 KBUILD_VMLINUX_OBJS += $(patsubst %/,%/built-in.a, $(drivers-y))
1159
1160 export KBUILD_VMLINUX_OBJS KBUILD_VMLINUX_LIBS
1161 export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1162 # used by scripts/Makefile.package
1163 export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) LICENSES arch include scripts tools)
1164
1165 vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
1166
1167 # Recurse until adjust_autoksyms.sh is satisfied
1168 PHONY += autoksyms_recursive
1169 ifdef CONFIG_TRIM_UNUSED_KSYMS
1170 # For the kernel to actually contain only the needed exported symbols,
1171 # we have to build modules as well to determine what those symbols are.
1172 # (this can be evaluated only once include/config/auto.conf has been included)
1173 KBUILD_MODULES := 1
1174
1175 autoksyms_recursive: descend modules.order
1176         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1177           "$(MAKE) -f $(srctree)/Makefile vmlinux"
1178 endif
1179
1180 autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1181
1182 quiet_cmd_autoksyms_h = GEN     $@
1183       cmd_autoksyms_h = mkdir -p $(dir $@); \
1184                         $(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@
1185
1186 $(autoksyms_h):
1187         $(call cmd,autoksyms_h)
1188
1189 ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1190
1191 # Final link of vmlinux with optional arch pass after final link
1192 cmd_link-vmlinux =                                                 \
1193         $(CONFIG_SHELL) $< "$(LD)" "$(KBUILD_LDFLAGS)" "$(LDFLAGS_vmlinux)";    \
1194         $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1195
1196 vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1197         +$(call if_changed,link-vmlinux)
1198
1199 targets := vmlinux
1200
1201 # The actual objects are generated when descending,
1202 # make sure no implicit rule kicks in
1203 $(sort $(vmlinux-deps) $(subdir-modorder)): descend ;
1204
1205 filechk_kernel.release = \
1206         echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1207
1208 # Store (new) KERNELRELEASE string in include/config/kernel.release
1209 include/config/kernel.release: FORCE
1210         $(call filechk,kernel.release)
1211
1212 # Additional helpers built in scripts/
1213 # Carefully list dependencies so we do not try to build scripts twice
1214 # in parallel
1215 PHONY += scripts
1216 scripts: scripts_basic scripts_dtc
1217         $(Q)$(MAKE) $(build)=$(@)
1218
1219 # Things we need to do before we recursively start building the kernel
1220 # or the modules are listed in "prepare".
1221 # A multi level approach is used. prepareN is processed before prepareN-1.
1222 # archprepare is used in arch Makefiles and when processed asm symlink,
1223 # version.h and scripts_basic is processed / created.
1224
1225 PHONY += prepare archprepare
1226
1227 archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1228         asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h \
1229         include/generated/autoconf.h
1230
1231 prepare0: archprepare
1232         $(Q)$(MAKE) $(build)=scripts/mod
1233         $(Q)$(MAKE) $(build)=.
1234
1235 # All the preparing..
1236 prepare: prepare0 prepare-objtool prepare-resolve_btfids
1237
1238 # Support for using generic headers in asm-generic
1239 asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1240
1241 PHONY += asm-generic uapi-asm-generic
1242 asm-generic: uapi-asm-generic
1243         $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1244         generic=include/asm-generic
1245 uapi-asm-generic:
1246         $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1247         generic=include/uapi/asm-generic
1248
1249 PHONY += prepare-objtool prepare-resolve_btfids
1250 prepare-objtool: $(objtool_target)
1251 ifeq ($(SKIP_STACK_VALIDATION),1)
1252 ifdef CONFIG_UNWINDER_ORC
1253         @echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1254         @false
1255 else
1256         @echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1257 endif
1258 endif
1259
1260 prepare-resolve_btfids: $(resolve_btfids_target)
1261 ifeq ($(ERROR_RESOLVE_BTFIDS),1)
1262         @echo "error: Cannot resolve BTF IDs for CONFIG_DEBUG_INFO_BTF, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1263         @false
1264 endif
1265 # Generate some files
1266 # ---------------------------------------------------------------------------
1267
1268 # KERNELRELEASE can change from a few different places, meaning version.h
1269 # needs to be updated, so this check is forced on all builds
1270
1271 uts_len := 64
1272 define filechk_utsrelease.h
1273         if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1274           echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1275           exit 1;                                                         \
1276         fi;                                                               \
1277         echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1278 endef
1279
1280 define filechk_version.h
1281         echo \#define LINUX_VERSION_CODE $(shell                         \
1282         expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1283         echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))'
1284 endef
1285
1286 $(version_h): FORCE
1287         $(call filechk,version.h)
1288         $(Q)rm -f $(old_version_h)
1289
1290 include/generated/utsrelease.h: include/config/kernel.release FORCE
1291         $(call filechk,utsrelease.h)
1292
1293 PHONY += headerdep
1294 headerdep:
1295         $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1296         $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1297
1298 # ---------------------------------------------------------------------------
1299 # Kernel headers
1300
1301 #Default location for installed headers
1302 export INSTALL_HDR_PATH = $(objtree)/usr
1303
1304 quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1305       cmd_headers_install = \
1306         mkdir -p $(INSTALL_HDR_PATH); \
1307         rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1308         usr/include $(INSTALL_HDR_PATH)
1309
1310 PHONY += headers_install
1311 headers_install: headers
1312         $(call cmd,headers_install)
1313
1314 PHONY += archheaders archscripts
1315
1316 hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1317
1318 PHONY += headers
1319 headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1320         $(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1321           $(error Headers not exportable for the $(SRCARCH) architecture))
1322         $(Q)$(MAKE) $(hdr-inst)=include/uapi
1323         $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1324         $(Q)$(MAKE) $(hdr-inst)=ubuntu/include dst=include oldheaders=
1325
1326 # Deprecated. It is no-op now.
1327 PHONY += headers_check
1328 headers_check:
1329         @:
1330
1331 ifdef CONFIG_HEADERS_INSTALL
1332 prepare: headers
1333 endif
1334
1335 PHONY += scripts_unifdef
1336 scripts_unifdef: scripts_basic
1337         $(Q)$(MAKE) $(build)=scripts scripts/unifdef
1338
1339 # ---------------------------------------------------------------------------
1340 # Kernel selftest
1341
1342 PHONY += kselftest
1343 kselftest:
1344         $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1345
1346 kselftest-%: FORCE
1347         $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1348
1349 PHONY += kselftest-merge
1350 kselftest-merge:
1351         $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1352         $(Q)find $(srctree)/tools/testing/selftests -name config | \
1353                 xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1354         $(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1355
1356 # ---------------------------------------------------------------------------
1357 # Devicetree files
1358
1359 ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1360 dtstree := arch/$(SRCARCH)/boot/dts
1361 endif
1362
1363 ifneq ($(dtstree),)
1364
1365 %.dtb: include/config/kernel.release scripts_dtc
1366         $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1367
1368 PHONY += dtbs dtbs_install dtbs_check
1369 dtbs: include/config/kernel.release scripts_dtc
1370         $(Q)$(MAKE) $(build)=$(dtstree)
1371
1372 ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1373 export CHECK_DTBS=y
1374 dtbs: dt_binding_check
1375 endif
1376
1377 dtbs_check: dtbs
1378
1379 dtbs_install:
1380         $(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1381
1382 ifdef CONFIG_OF_EARLY_FLATTREE
1383 all: dtbs
1384 endif
1385
1386 endif
1387
1388 PHONY += scripts_dtc
1389 scripts_dtc: scripts_basic
1390         $(Q)$(MAKE) $(build)=scripts/dtc
1391
1392 ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1393 export CHECK_DT_BINDING=y
1394 endif
1395
1396 PHONY += dt_binding_check
1397 dt_binding_check: scripts_dtc
1398         $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1399
1400 # ---------------------------------------------------------------------------
1401 # Modules
1402
1403 ifdef CONFIG_MODULES
1404
1405 # By default, build modules as well
1406
1407 all: modules
1408
1409 # When we're building modules with modversions, we need to consider
1410 # the built-in objects during the descend as well, in order to
1411 # make sure the checksums are up to date before we record them.
1412 ifdef CONFIG_MODVERSIONS
1413   KBUILD_BUILTIN := 1
1414 endif
1415
1416 # Build modules
1417 #
1418 # A module can be listed more than once in obj-m resulting in
1419 # duplicate lines in modules.order files.  Those are removed
1420 # using awk while concatenating to the final file.
1421
1422 PHONY += modules
1423 modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_check modules_prepare
1424         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1425
1426 PHONY += modules_check
1427 modules_check: modules.order
1428         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1429
1430 cmd_modules_order = $(AWK) '!x[$$0]++' $(real-prereqs) > $@
1431
1432 modules.order: $(subdir-modorder) FORCE
1433         $(call if_changed,modules_order)
1434
1435 targets += modules.order
1436
1437 # Target to prepare building external modules
1438 PHONY += modules_prepare
1439 modules_prepare: prepare
1440         $(Q)$(MAKE) $(build)=scripts scripts/module.lds
1441
1442 # Target to install modules
1443 PHONY += modules_install
1444 modules_install: _modinst_ _modinst_post
1445
1446 PHONY += _modinst_
1447 _modinst_:
1448         @rm -rf $(MODLIB)/kernel
1449         @rm -f $(MODLIB)/source
1450         @mkdir -p $(MODLIB)/kernel
1451         @ln -s $(abspath $(srctree)) $(MODLIB)/source
1452         @if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
1453                 rm -f $(MODLIB)/build ; \
1454                 ln -s $(CURDIR) $(MODLIB)/build ; \
1455         fi
1456         @sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order
1457         @cp -f modules.builtin $(MODLIB)/
1458         @cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
1459         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1460
1461 # This depmod is only for convenience to give the initial
1462 # boot a modules.dep even before / is mounted read-write.  However the
1463 # boot script depmod is the master version.
1464 PHONY += _modinst_post
1465 _modinst_post: _modinst_
1466         $(call cmd,depmod)
1467
1468 ifeq ($(CONFIG_MODULE_SIG), y)
1469 PHONY += modules_sign
1470 modules_sign:
1471         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1472 endif
1473
1474 else # CONFIG_MODULES
1475
1476 # Modules not configured
1477 # ---------------------------------------------------------------------------
1478
1479 PHONY += modules modules_install
1480 modules modules_install:
1481         @echo >&2
1482         @echo >&2 "The present kernel configuration has modules disabled."
1483         @echo >&2 "Type 'make config' and enable loadable module support."
1484         @echo >&2 "Then build a kernel with module support enabled."
1485         @echo >&2
1486         @exit 1
1487
1488 endif # CONFIG_MODULES
1489
1490 ###
1491 # Cleaning is done on three levels.
1492 # make clean     Delete most generated files
1493 #                Leave enough to build external modules
1494 # make mrproper  Delete the current configuration, and all generated files
1495 # make distclean Remove editor backup files, patch leftover files and the like
1496
1497 # Directories & files removed with 'make clean'
1498 CLEAN_FILES += include/ksym vmlinux.symvers \
1499                modules.builtin modules.builtin.modinfo modules.nsdeps \
1500                compile_commands.json
1501
1502 # Directories & files removed with 'make mrproper'
1503 MRPROPER_FILES += include/config include/generated          \
1504                   arch/$(SRCARCH)/include/generated .tmp_objdiff \
1505                   debian snap tar-install \
1506                   .config .config.old .version \
1507                   Module.symvers \
1508                   signing_key.pem signing_key.priv signing_key.x509     \
1509                   x509.genkey extra_certificates signing_key.x509.keyid \
1510                   signing_key.x509.signer vmlinux-gdb.py \
1511                   *.spec
1512
1513 # Directories & files removed with 'make distclean'
1514 DISTCLEAN_FILES += tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS
1515
1516 # clean - Delete most, but leave enough to build external modules
1517 #
1518 clean: rm-files := $(CLEAN_FILES)
1519
1520 PHONY += archclean vmlinuxclean
1521
1522 vmlinuxclean:
1523         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1524         $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1525
1526 clean: archclean vmlinuxclean
1527
1528 # mrproper - Delete all generated files, including .config
1529 #
1530 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1531 mrproper-dirs      := $(addprefix _mrproper_,scripts)
1532
1533 PHONY += $(mrproper-dirs) mrproper
1534 $(mrproper-dirs):
1535         $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1536
1537 mrproper: clean $(mrproper-dirs)
1538         $(call cmd,rmfiles)
1539
1540 # distclean
1541 #
1542 distclean: rm-files := $(wildcard $(DISTCLEAN_FILES))
1543
1544 PHONY += distclean
1545
1546 distclean: mrproper
1547         $(call cmd,rmfiles)
1548         @find $(srctree) $(RCS_FIND_IGNORE) \
1549                 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1550                 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1551                 -o -name 'core' \) \
1552                 -type f -print | xargs rm -f
1553
1554
1555 # Packaging of the kernel to various formats
1556 # ---------------------------------------------------------------------------
1557
1558 %src-pkg: FORCE
1559         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1560 %pkg: include/config/kernel.release FORCE
1561         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1562
1563 # Brief documentation of the typical targets used
1564 # ---------------------------------------------------------------------------
1565
1566 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1567 boards := $(sort $(notdir $(boards)))
1568 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1569 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1570
1571 PHONY += help
1572 help:
1573         @echo  'Cleaning targets:'
1574         @echo  '  clean           - Remove most generated files but keep the config and'
1575         @echo  '                    enough build support to build external modules'
1576         @echo  '  mrproper        - Remove all generated files + config + various backup files'
1577         @echo  '  distclean       - mrproper + remove editor backup and patch files'
1578         @echo  ''
1579         @echo  'Configuration targets:'
1580         @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1581         @echo  ''
1582         @echo  'Other generic targets:'
1583         @echo  '  all             - Build all targets marked with [*]'
1584         @echo  '* vmlinux         - Build the bare kernel'
1585         @echo  '* modules         - Build all modules'
1586         @echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1587         @echo  '  dir/            - Build all files in dir and below'
1588         @echo  '  dir/file.[ois]  - Build specified target only'
1589         @echo  '  dir/file.ll     - Build the LLVM assembly file'
1590         @echo  '                    (requires compiler support for LLVM assembly generation)'
1591         @echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1592         @echo  '                    (requires a recent binutils and recent build (System.map))'
1593         @echo  '  dir/file.ko     - Build module including final link'
1594         @echo  '  modules_prepare - Set up for building external modules'
1595         @echo  '  tags/TAGS       - Generate tags file for editors'
1596         @echo  '  cscope          - Generate cscope index'
1597         @echo  '  gtags           - Generate GNU GLOBAL index'
1598         @echo  '  kernelrelease   - Output the release version string (use with make -s)'
1599         @echo  '  kernelversion   - Output the version stored in Makefile (use with make -s)'
1600         @echo  '  image_name      - Output the image name (use with make -s)'
1601         @echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1602          echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1603          echo  ''
1604         @echo  'Static analysers:'
1605         @echo  '  checkstack      - Generate a list of stack hogs'
1606         @echo  '  versioncheck    - Sanity check on version.h usage'
1607         @echo  '  includecheck    - Check for duplicate included header files'
1608         @echo  '  export_report   - List the usages of all exported symbols'
1609         @echo  '  headerdep       - Detect inclusion cycles in headers'
1610         @echo  '  coccicheck      - Check with Coccinelle'
1611         @echo  '  clang-analyzer  - Check with clang static analyzer'
1612         @echo  '  clang-tidy      - Check with clang-tidy'
1613         @echo  ''
1614         @echo  'Tools:'
1615         @echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1616         @echo  ''
1617         @echo  'Kernel selftest:'
1618         @echo  '  kselftest         - Build and run kernel selftest'
1619         @echo  '                      Build, install, and boot kernel before'
1620         @echo  '                      running kselftest on it'
1621         @echo  '                      Run as root for full coverage'
1622         @echo  '  kselftest-all     - Build kernel selftest'
1623         @echo  '  kselftest-install - Build and install kernel selftest'
1624         @echo  '  kselftest-clean   - Remove all generated kselftest files'
1625         @echo  '  kselftest-merge   - Merge all the config dependencies of'
1626         @echo  '                      kselftest to existing .config.'
1627         @echo  ''
1628         @$(if $(dtstree), \
1629                 echo 'Devicetree:'; \
1630                 echo '* dtbs             - Build device tree blobs for enabled boards'; \
1631                 echo '  dtbs_install     - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1632                 echo '  dt_binding_check - Validate device tree binding documents'; \
1633                 echo '  dtbs_check       - Validate device tree source files';\
1634                 echo '')
1635
1636         @echo 'Userspace tools targets:'
1637         @echo '  use "make tools/help"'
1638         @echo '  or  "cd tools; make help"'
1639         @echo  ''
1640         @echo  'Kernel packaging:'
1641         @$(MAKE) -f $(srctree)/scripts/Makefile.package help
1642         @echo  ''
1643         @echo  'Documentation targets:'
1644         @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1645         @echo  ''
1646         @echo  'Architecture specific targets ($(SRCARCH)):'
1647         @$(if $(archhelp),$(archhelp),\
1648                 echo '  No architecture specific help defined for $(SRCARCH)')
1649         @echo  ''
1650         @$(if $(boards), \
1651                 $(foreach b, $(boards), \
1652                 printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1653                 echo '')
1654         @$(if $(board-dirs), \
1655                 $(foreach b, $(board-dirs), \
1656                 printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1657                 printf "  %-16s - Show all of the above\\n" help-boards; \
1658                 echo '')
1659
1660         @echo  '  make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1661         @echo  '  make V=2   [targets] 2 => give reason for rebuild of target'
1662         @echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1663         @echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1664         @echo  '                       (sparse by default)'
1665         @echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1666         @echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1667         @echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
1668         @echo  '                1: warnings which may be relevant and do not occur too often'
1669         @echo  '                2: warnings which occur quite often but may still be relevant'
1670         @echo  '                3: more obscure warnings, can most likely be ignored'
1671         @echo  '                Multiple levels can be combined with W=12 or W=123'
1672         @echo  ''
1673         @echo  'Execute "make" or "make all" to build all targets marked with [*] '
1674         @echo  'For further info see the ./README file'
1675
1676
1677 help-board-dirs := $(addprefix help-,$(board-dirs))
1678
1679 help-boards: $(help-board-dirs)
1680
1681 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1682
1683 $(help-board-dirs): help-%:
1684         @echo  'Architecture specific targets ($(SRCARCH) $*):'
1685         @$(if $(boards-per-dir), \
1686                 $(foreach b, $(boards-per-dir), \
1687                 printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1688                 echo '')
1689
1690
1691 # Documentation targets
1692 # ---------------------------------------------------------------------------
1693 DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1694                linkcheckdocs dochelp refcheckdocs
1695 PHONY += $(DOC_TARGETS)
1696 $(DOC_TARGETS):
1697         $(Q)$(MAKE) $(build)=Documentation $@
1698
1699 # Misc
1700 # ---------------------------------------------------------------------------
1701
1702 PHONY += scripts_gdb
1703 scripts_gdb: prepare0
1704         $(Q)$(MAKE) $(build)=scripts/gdb
1705         $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1706
1707 ifdef CONFIG_GDB_SCRIPTS
1708 all: scripts_gdb
1709 endif
1710
1711 else # KBUILD_EXTMOD
1712
1713 ###
1714 # External module support.
1715 # When building external modules the kernel used as basis is considered
1716 # read-only, and no consistency checks are made and the make
1717 # system is not used on the basis kernel. If updates are required
1718 # in the basis kernel ordinary make commands (without M=...) must
1719 # be used.
1720 #
1721 # The following are the only valid targets when building external
1722 # modules.
1723 # make M=dir clean     Delete all automatically generated files
1724 # make M=dir modules   Make all modules in specified dir
1725 # make M=dir           Same as 'make M=dir modules'
1726 # make M=dir modules_install
1727 #                      Install the modules built in the module directory
1728 #                      Assumes install directory is already created
1729
1730 # We are always building only modules.
1731 KBUILD_BUILTIN :=
1732 KBUILD_MODULES := 1
1733
1734 build-dirs := $(KBUILD_EXTMOD)
1735 PHONY += modules
1736 modules: $(MODORDER)
1737         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1738
1739 $(MODORDER): descend
1740         @:
1741
1742 PHONY += modules_install
1743 modules_install: _emodinst_ _emodinst_post
1744
1745 install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1746 PHONY += _emodinst_
1747 _emodinst_:
1748         $(Q)mkdir -p $(MODLIB)/$(install-dir)
1749         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1750
1751 PHONY += _emodinst_post
1752 _emodinst_post: _emodinst_
1753         $(call cmd,depmod)
1754
1755 compile_commands.json: $(extmod-prefix)compile_commands.json
1756 PHONY += compile_commands.json
1757
1758 clean-dirs := $(KBUILD_EXTMOD)
1759 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1760         $(KBUILD_EXTMOD)/compile_commands.json
1761
1762 PHONY += help
1763 help:
1764         @echo  '  Building external modules.'
1765         @echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1766         @echo  ''
1767         @echo  '  modules         - default target, build the module(s)'
1768         @echo  '  modules_install - install the module'
1769         @echo  '  clean           - remove generated files in module directory only'
1770         @echo  ''
1771
1772 # no-op for external module builds
1773 PHONY += prepare modules_prepare
1774
1775 endif # KBUILD_EXTMOD
1776
1777 # Single targets
1778 # ---------------------------------------------------------------------------
1779 # To build individual files in subdirectories, you can do like this:
1780 #
1781 #   make foo/bar/baz.s
1782 #
1783 # The supported suffixes for single-target are listed in 'single-targets'
1784 #
1785 # To build only under specific subdirectories, you can do like this:
1786 #
1787 #   make foo/bar/baz/
1788
1789 ifdef single-build
1790
1791 # .ko is special because modpost is needed
1792 single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1793 single-no-ko := $(sort $(patsubst %.ko,%.mod, $(MAKECMDGOALS)))
1794
1795 $(single-ko): single_modpost
1796         @:
1797 $(single-no-ko): descend
1798         @:
1799
1800 ifeq ($(KBUILD_EXTMOD),)
1801 # For the single build of in-tree modules, use a temporary file to avoid
1802 # the situation of modules_install installing an invalid modules.order.
1803 MODORDER := .modules.tmp
1804 endif
1805
1806 PHONY += single_modpost
1807 single_modpost: $(single-no-ko) modules_prepare
1808         $(Q){ $(foreach m, $(single-ko), echo $(extmod-prefix)$m;) } > $(MODORDER)
1809         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1810
1811 KBUILD_MODULES := 1
1812
1813 export KBUILD_SINGLE_TARGETS := $(addprefix $(extmod-prefix), $(single-no-ko))
1814
1815 # trim unrelated directories
1816 build-dirs := $(foreach d, $(build-dirs), \
1817                         $(if $(filter $(d)/%, $(KBUILD_SINGLE_TARGETS)), $(d)))
1818
1819 endif
1820
1821 ifndef CONFIG_MODULES
1822 KBUILD_MODULES :=
1823 endif
1824
1825 # Handle descending into subdirectories listed in $(build-dirs)
1826 # Preset locale variables to speed up the build process. Limit locale
1827 # tweaks to this spot to avoid wrong language settings when running
1828 # make menuconfig etc.
1829 # Error messages still appears in the original language
1830 PHONY += descend $(build-dirs)
1831 descend: $(build-dirs)
1832 $(build-dirs): prepare
1833         $(Q)$(MAKE) $(build)=$@ \
1834         single-build=$(if $(filter-out $@/, $(filter $@/%, $(KBUILD_SINGLE_TARGETS))),1) \
1835         need-builtin=1 need-modorder=1
1836
1837 clean-dirs := $(addprefix _clean_, $(clean-dirs))
1838 PHONY += $(clean-dirs) clean
1839 $(clean-dirs):
1840         $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1841
1842 clean: $(clean-dirs)
1843         $(call cmd,rmfiles)
1844         @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1845                 \( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1846                 -o -name '*.ko.*' \
1847                 -o -name '*.dtb' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1848                 -o -name '*.dwo' -o -name '*.lst' \
1849                 -o -name '*.su' -o -name '*.mod' \
1850                 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1851                 -o -name '*.lex.c' -o -name '*.tab.[ch]' \
1852                 -o -name '*.asn1.[ch]' \
1853                 -o -name '*.symtypes' -o -name 'modules.order' \
1854                 -o -name '.tmp_*.o.*' \
1855                 -o -name '*.c.[012]*.*' \
1856                 -o -name '*.ll' \
1857                 -o -name '*.gcno' \) -type f -print | xargs rm -f
1858
1859 # Generate tags for editors
1860 # ---------------------------------------------------------------------------
1861 quiet_cmd_tags = GEN     $@
1862       cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1863
1864 tags TAGS cscope gtags: FORCE
1865         $(call cmd,tags)
1866
1867 # Script to generate missing namespace dependencies
1868 # ---------------------------------------------------------------------------
1869
1870 PHONY += nsdeps
1871 nsdeps: export KBUILD_NSDEPS=1
1872 nsdeps: modules
1873         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1874
1875 # Clang Tooling
1876 # ---------------------------------------------------------------------------
1877
1878 quiet_cmd_gen_compile_commands = GEN     $@
1879       cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
1880
1881 $(extmod-prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
1882         $(if $(KBUILD_EXTMOD),,$(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)) \
1883         $(if $(CONFIG_MODULES), $(MODORDER)) FORCE
1884         $(call if_changed,gen_compile_commands)
1885
1886 targets += $(extmod-prefix)compile_commands.json
1887
1888 PHONY += clang-tidy clang-analyzer
1889
1890 ifdef CONFIG_CC_IS_CLANG
1891 quiet_cmd_clang_tools = CHECK   $<
1892       cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
1893
1894 clang-tidy clang-analyzer: $(extmod-prefix)compile_commands.json
1895         $(call cmd,clang_tools)
1896 else
1897 clang-tidy clang-analyzer:
1898         @echo "$@ requires CC=clang" >&2
1899         @false
1900 endif
1901
1902 # Scripts to check various things for consistency
1903 # ---------------------------------------------------------------------------
1904
1905 PHONY += includecheck versioncheck coccicheck export_report
1906
1907 includecheck:
1908         find $(srctree)/* $(RCS_FIND_IGNORE) \
1909                 -name '*.[hcS]' -type f -print | sort \
1910                 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1911
1912 versioncheck:
1913         find $(srctree)/* $(RCS_FIND_IGNORE) \
1914                 -name '*.[hcS]' -type f -print | sort \
1915                 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1916
1917 coccicheck:
1918         $(Q)$(BASH) $(srctree)/scripts/$@
1919
1920 export_report:
1921         $(PERL) $(srctree)/scripts/export_report.pl
1922
1923 PHONY += checkstack kernelrelease kernelversion image_name
1924
1925 # UML needs a little special treatment here.  It wants to use the host
1926 # toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
1927 # else wants $(ARCH), including people doing cross-builds, which means
1928 # that $(SUBARCH) doesn't work here.
1929 ifeq ($(ARCH), um)
1930 CHECKSTACK_ARCH := $(SUBARCH)
1931 else
1932 CHECKSTACK_ARCH := $(ARCH)
1933 endif
1934 checkstack:
1935         $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1936         $(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1937
1938 kernelrelease:
1939         @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1940
1941 kernelversion:
1942         @echo $(KERNELVERSION)
1943
1944 image_name:
1945         @echo $(KBUILD_IMAGE)
1946
1947 # Clear a bunch of variables before executing the submake
1948
1949 ifeq ($(quiet),silent_)
1950 tools_silent=s
1951 endif
1952
1953 tools/: FORCE
1954         $(Q)mkdir -p $(objtree)/tools
1955         $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1956
1957 tools/%: FORCE
1958         $(Q)mkdir -p $(objtree)/tools
1959         $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1960
1961 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
1962       cmd_rmfiles = rm -rf $(rm-files)
1963
1964 # Run depmod only if we have System.map and depmod is executable
1965 quiet_cmd_depmod = DEPMOD  $(KERNELRELEASE)
1966       cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1967                    $(KERNELRELEASE)
1968
1969 # read saved command lines for existing targets
1970 existing-targets := $(wildcard $(sort $(targets)))
1971
1972 -include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
1973
1974 endif # config-build
1975 endif # mixed-build
1976 endif # need-sub-make
1977
1978 PHONY += FORCE
1979 FORCE:
1980
1981 # Declare the contents of the PHONY variable as phony.  We keep that
1982 # information in a variable so we can use it in if_changed and friends.
1983 .PHONY: $(PHONY)