Makefile

   1 # SPDX-License-Identifier: GPL-2.0
   2 VERSION = 5
   3 PATCHLEVEL = 15
   4 SUBLEVEL = 18
   5 EXTRAVERSION =
   6 NAME = Trick or Treat
   7
   8 # *DOCUMENTATION*
   9 # To see a list of typical targets execute "make help"
  10 # More info can be located in ./README
  11 # Comments in this file are targeted only to the developer, do not
  12 # expect to learn how to build the kernel reading this file.
  13
  14 $(if $(filter __%, $(MAKECMDGOALS)), \
  15         $(error targets prefixed with '__' are only for internal use))
  16
  17 # That's our default target when none is given on the command line
  18 PHONY := __all
  19 __all:
  20
  21 # We are using a recursive build, so we need to do a little thinking
  22 # to get the ordering right.
  23 #
  24 # Most importantly: sub-Makefiles should only ever modify files in
  25 # their own directory. If in some directory we have a dependency on
  26 # a file in another dir (which doesn't happen often, but it's often
  27 # unavoidable when linking the built-in.a targets which finally
  28 # turn into vmlinux), we will call a sub make in that other dir, and
  29 # after that we are sure that everything which is in that other dir
  30 # is now up to date.
  31 #
  32 # The only cases where we need to modify files which have global
  33 # effects are thus separated out and done before the recursive
  34 # descending is started. They are now explicitly listed as the
  35 # prepare rule.
  36
  37 ifneq ($(sub_make_done),1)
  38
  39 # Do not use make's built-in rules and variables
  40 # (this increases performance and avoids hard-to-debug behaviour)
  41 MAKEFLAGS += -rR
  42
  43 # Avoid funny character set dependencies
  44 unexport LC_ALL
  45 LC_COLLATE=C
  46 LC_NUMERIC=C
  47 export LC_COLLATE LC_NUMERIC
  48
  49 # Avoid interference with shell env settings
  50 unexport GREP_OPTIONS
  51
  52 # Beautify output
  53 # ---------------------------------------------------------------------------
  54 #
  55 # Normally, we echo the whole command before executing it. By making
  56 # that echo $($(quiet)$(cmd)), we now have the possibility to set
  57 # $(quiet) to choose other forms of output instead, e.g.
  58 #
  59 #         quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
  60 #         cmd_cc_o_c       = $(CC) $(c_flags) -c -o $@ $<
  61 #
  62 # If $(quiet) is empty, the whole command will be printed.
  63 # If it is set to "quiet_", only the short version will be printed.
  64 # If it is set to "silent_", nothing will be printed at all, since
  65 # the variable $(silent_cmd_cc_o_c) doesn't exist.
  66 #
  67 # A simple variant is to prefix commands with $(Q) - that's useful
  68 # for commands that shall be hidden in non-verbose mode.
  69 #
  70 #       $(Q)ln $@ :<
  71 #
  72 # If KBUILD_VERBOSE equals 0 then the above command will be hidden.
  73 # If KBUILD_VERBOSE equals 1 then the above command is displayed.
  74 # If KBUILD_VERBOSE equals 2 then give the reason why each target is rebuilt.
  75 #
  76 # To put more focus on warnings, be less verbose as default
  77 # Use 'make V=1' to see the full commands
  78
  79 ifeq ("$(origin V)", "command line")
  80   KBUILD_VERBOSE = $(V)
  81 endif
  82 ifndef KBUILD_VERBOSE
  83   KBUILD_VERBOSE = 0
  84 endif
  85
  86 ifeq ($(KBUILD_VERBOSE),1)
  87   quiet =
  88   Q =
  89 else
  90   quiet=quiet_
  91   Q = @
  92 endif
  93
  94 # If the user is running make -s (silent mode), suppress echoing of
  95 # commands
  96
  97 ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
  98   quiet=silent_
  99   KBUILD_VERBOSE = 0
 100 endif
 101
 102 export quiet Q KBUILD_VERBOSE
 103
 104 # Call a source code checker (by default, "sparse") as part of the
 105 # C compilation.
 106 #
 107 # Use 'make C=1' to enable checking of only re-compiled files.
 108 # Use 'make C=2' to enable checking of *all* source files, regardless
 109 # of whether they are re-compiled or not.
 110 #
 111 # See the file "Documentation/dev-tools/sparse.rst" for more details,
 112 # including where to get the "sparse" utility.
 113
 114 ifeq ("$(origin C)", "command line")
 115   KBUILD_CHECKSRC = $(C)
 116 endif
 117 ifndef KBUILD_CHECKSRC
 118   KBUILD_CHECKSRC = 0
 119 endif
 120
 121 export KBUILD_CHECKSRC
 122
 123 # Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
 124 # directory of external module to build. Setting M= takes precedence.
 125 ifeq ("$(origin M)", "command line")
 126   KBUILD_EXTMOD := $(M)
 127 endif
 128
 129 $(if $(word 2, $(KBUILD_EXTMOD)), \
 130         $(error building multiple external modules is not supported))
 131
 132 # Remove trailing slashes
 133 ifneq ($(filter %/, $(KBUILD_EXTMOD)),)
 134 KBUILD_EXTMOD := $(shell dirname $(KBUILD_EXTMOD).)
 135 endif
 136
 137 export KBUILD_EXTMOD
 138
 139 # Kbuild will save output files in the current working directory.
 140 # This does not need to match to the root of the kernel source tree.
 141 #
 142 # For example, you can do this:
 143 #
 144 #  cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
 145 #
 146 # If you want to save output files in a different location, there are
 147 # two syntaxes to specify it.
 148 #
 149 # 1) O=
 150 # Use "make O=dir/to/store/output/files/"
 151 #
 152 # 2) Set KBUILD_OUTPUT
 153 # Set the environment variable KBUILD_OUTPUT to point to the output directory.
 154 # export KBUILD_OUTPUT=dir/to/store/output/files/; make
 155 #
 156 # The O= assignment takes precedence over the KBUILD_OUTPUT environment
 157 # variable.
 158
 159 # Do we want to change the working directory?
 160 ifeq ("$(origin O)", "command line")
 161   KBUILD_OUTPUT := $(O)
 162 endif
 163
 164 ifneq ($(KBUILD_OUTPUT),)
 165 # Make's built-in functions such as $(abspath ...), $(realpath ...) cannot
 166 # expand a shell special character '~'. We use a somewhat tedious way here.
 167 abs_objtree := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) && pwd)
 168 $(if $(abs_objtree),, \
 169      $(error failed to create output directory "$(KBUILD_OUTPUT)"))
 170
 171 # $(realpath ...) resolves symlinks
 172 abs_objtree := $(realpath $(abs_objtree))
 173 else
 174 abs_objtree := $(CURDIR)
 175 endif # ifneq ($(KBUILD_OUTPUT),)
 176
 177 ifeq ($(abs_objtree),$(CURDIR))
 178 # Suppress "Entering directory ..." unless we are changing the work directory.
 179 MAKEFLAGS += --no-print-directory
 180 else
 181 need-sub-make := 1
 182 endif
 183
 184 this-makefile := $(lastword $(MAKEFILE_LIST))
 185 abs_srctree := $(realpath $(dir $(this-makefile)))
 186
 187 ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
 188 $(error source directory cannot contain spaces or colons)
 189 endif
 190
 191 ifneq ($(abs_srctree),$(abs_objtree))
 192 # Look for make include files relative to root of kernel src
 193 #
 194 # --included-dir is added for backward compatibility, but you should not rely on
 195 # it. Please add $(srctree)/ prefix to include Makefiles in the source tree.
 196 MAKEFLAGS += --include-dir=$(abs_srctree)
 197 endif
 198
 199 ifneq ($(filter 3.%,$(MAKE_VERSION)),)
 200 # 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
 201 # We need to invoke sub-make to avoid implicit rules in the top Makefile.
 202 need-sub-make := 1
 203 # Cancel implicit rules for this Makefile.
 204 $(this-makefile): ;
 205 endif
 206
 207 export abs_srctree abs_objtree
 208 export sub_make_done := 1
 209
 210 ifeq ($(need-sub-make),1)
 211
 212 PHONY += $(MAKECMDGOALS) __sub-make
 213
 214 $(filter-out $(this-makefile), $(MAKECMDGOALS)) __all: __sub-make
 215         @:
 216
 217 # Invoke a second make in the output directory, passing relevant variables
 218 __sub-make:
 219         $(Q)$(MAKE) -C $(abs_objtree) -f $(abs_srctree)/Makefile $(MAKECMDGOALS)
 220
 221 endif # need-sub-make
 222 endif # sub_make_done
 223
 224 # We process the rest of the Makefile if this is the final invocation of make
 225 ifeq ($(need-sub-make),)
 226
 227 # Do not print "Entering directory ...",
 228 # but we want to display it when entering to the output directory
 229 # so that IDEs/editors are able to understand relative filenames.
 230 MAKEFLAGS += --no-print-directory
 231
 232 ifeq ($(abs_srctree),$(abs_objtree))
 233         # building in the source tree
 234         srctree := .
 235         building_out_of_srctree :=
 236 else
 237         ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
 238                 # building in a subdirectory of the source tree
 239                 srctree := ..
 240         else
 241                 srctree := $(abs_srctree)
 242         endif
 243         building_out_of_srctree := 1
 244 endif
 245
 246 ifneq ($(KBUILD_ABS_SRCTREE),)
 247 srctree := $(abs_srctree)
 248 endif
 249
 250 objtree         := .
 251 VPATH           := $(srctree)
 252
 253 export building_out_of_srctree srctree objtree VPATH
 254
 255 # To make sure we do not include .config for any of the *config targets
 256 # catch them early, and hand them over to scripts/kconfig/Makefile
 257 # It is allowed to specify more targets when calling make, including
 258 # mixing *config targets and build targets.
 259 # For example 'make oldconfig all'.
 260 # Detect when mixed targets is specified, and make a second invocation
 261 # of make so .config is not included in this case either (for *config).
 262
 263 version_h := include/generated/uapi/linux/version.h
 264
 265 clean-targets := %clean mrproper cleandocs
 266 no-dot-config-targets := $(clean-targets) \
 267                          cscope gtags TAGS tags help% %docs check% coccicheck \
 268                          $(version_h) headers headers_% archheaders archscripts \
 269                          %asm-generic kernelversion %src-pkg dt_binding_check \
 270                          outputmakefile
 271 # Installation targets should not require compiler. Unfortunately, vdso_install
 272 # is an exception where build artifacts may be updated. This must be fixed.
 273 no-compiler-targets := $(no-dot-config-targets) install dtbs_install \
 274                         headers_install modules_install kernelrelease image_name
 275 no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease \
 276                           image_name
 277 single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
 278
 279 config-build    :=
 280 mixed-build     :=
 281 need-config     := 1
 282 need-compiler   := 1
 283 may-sync-config := 1
 284 single-build    :=
 285
 286 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
 287         ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
 288                 need-config :=
 289         endif
 290 endif
 291
 292 ifneq ($(filter $(no-compiler-targets), $(MAKECMDGOALS)),)
 293         ifeq ($(filter-out $(no-compiler-targets), $(MAKECMDGOALS)),)
 294                 need-compiler :=
 295         endif
 296 endif
 297
 298 ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
 299         ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
 300                 may-sync-config :=
 301         endif
 302 endif
 303
 304 ifneq ($(KBUILD_EXTMOD),)
 305         may-sync-config :=
 306 endif
 307
 308 ifeq ($(KBUILD_EXTMOD),)
 309         ifneq ($(filter %config,$(MAKECMDGOALS)),)
 310                 config-build := 1
 311                 ifneq ($(words $(MAKECMDGOALS)),1)
 312                         mixed-build := 1
 313                 endif
 314         endif
 315 endif
 316
 317 # We cannot build single targets and the others at the same time
 318 ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
 319         single-build := 1
 320         ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
 321                 mixed-build := 1
 322         endif
 323 endif
 324
 325 # For "make -j clean all", "make -j mrproper defconfig all", etc.
 326 ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
 327         ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
 328                 mixed-build := 1
 329         endif
 330 endif
 331
 332 # install and modules_install need also be processed one by one
 333 ifneq ($(filter install,$(MAKECMDGOALS)),)
 334         ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
 335                 mixed-build := 1
 336         endif
 337 endif
 338
 339 ifdef mixed-build
 340 # ===========================================================================
 341 # We're called with mixed targets (*config and build targets).
 342 # Handle them one by one.
 343
 344 PHONY += $(MAKECMDGOALS) __build_one_by_one
 345
 346 $(MAKECMDGOALS): __build_one_by_one
 347         @:
 348
 349 __build_one_by_one:
 350         $(Q)set -e; \
 351         for i in $(MAKECMDGOALS); do \
 352                 $(MAKE) -f $(srctree)/Makefile $$i; \
 353         done
 354
 355 else # !mixed-build
 356
 357 include $(srctree)/scripts/Kbuild.include
 358
 359 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
 360 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
 361 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
 362 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
 363
 364 include $(srctree)/scripts/subarch.include
 365
 366 # Cross compiling and selecting different set of gcc/bin-utils
 367 # ---------------------------------------------------------------------------
 368 #
 369 # When performing cross compilation for other architectures ARCH shall be set
 370 # to the target architecture. (See arch/* for the possibilities).
 371 # ARCH can be set during invocation of make:
 372 # make ARCH=ia64
 373 # Another way is to have ARCH set in the environment.
 374 # The default ARCH is the host where make is executed.
 375
 376 # CROSS_COMPILE specify the prefix used for all executables used
 377 # during compilation. Only gcc and related bin-utils executables
 378 # are prefixed with $(CROSS_COMPILE).
 379 # CROSS_COMPILE can be set on the command line
 380 # make CROSS_COMPILE=ia64-linux-
 381 # Alternatively CROSS_COMPILE can be set in the environment.
 382 # Default value for CROSS_COMPILE is not to prefix executables
 383 # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
 384 ARCH            ?= $(SUBARCH)
 385
 386 # Architecture as present in compile.h
 387 UTS_MACHINE     := $(ARCH)
 388 SRCARCH         := $(ARCH)
 389
 390 # Additional ARCH settings for x86
 391 ifeq ($(ARCH),i386)
 392         SRCARCH := x86
 393 endif
 394 ifeq ($(ARCH),x86_64)
 395         SRCARCH := x86
 396 endif
 397
 398 # Additional ARCH settings for sparc
 399 ifeq ($(ARCH),sparc32)
 400        SRCARCH := sparc
 401 endif
 402 ifeq ($(ARCH),sparc64)
 403        SRCARCH := sparc
 404 endif
 405
 406 # Additional ARCH settings for parisc
 407 ifeq ($(ARCH),parisc64)
 408        SRCARCH := parisc
 409 endif
 410
 411 export cross_compiling :=
 412 ifneq ($(SRCARCH),$(SUBARCH))
 413 cross_compiling := 1
 414 endif
 415
 416 KCONFIG_CONFIG  ?= .config
 417 export KCONFIG_CONFIG
 418
 419 # SHELL used by kbuild
 420 CONFIG_SHELL := sh
 421
 422 HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
 423 HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
 424 HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
 425
 426 ifneq ($(LLVM),)
 427 HOSTCC  = clang
 428 HOSTCXX = clang++
 429 else
 430 HOSTCC  = gcc
 431 HOSTCXX = g++
 432 endif
 433
 434 export KBUILD_USERCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
 435                               -O2 -fomit-frame-pointer -std=gnu89
 436 export KBUILD_USERLDFLAGS :=
 437
 438 KBUILD_HOSTCFLAGS   := $(KBUILD_USERCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
 439 KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
 440 KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
 441 KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
 442
 443 # Make variables (CC, etc...)
 444 CPP             = $(CC) -E
 445 ifneq ($(LLVM),)
 446 CC              = clang
 447 LD              = ld.lld
 448 AR              = llvm-ar
 449 NM              = llvm-nm
 450 OBJCOPY         = llvm-objcopy
 451 OBJDUMP         = llvm-objdump
 452 READELF         = llvm-readelf
 453 STRIP           = llvm-strip
 454 else
 455 CC              = $(CROSS_COMPILE)gcc
 456 LD              = $(CROSS_COMPILE)ld
 457 AR              = $(CROSS_COMPILE)ar
 458 NM              = $(CROSS_COMPILE)nm
 459 OBJCOPY         = $(CROSS_COMPILE)objcopy
 460 OBJDUMP         = $(CROSS_COMPILE)objdump
 461 READELF         = $(CROSS_COMPILE)readelf
 462 STRIP           = $(CROSS_COMPILE)strip
 463 endif
 464 PAHOLE          = pahole
 465 RESOLVE_BTFIDS  = $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
 466 LEX             = flex
 467 YACC            = bison
 468 AWK             = awk
 469 INSTALLKERNEL  := installkernel
 470 DEPMOD          = depmod
 471 PERL            = perl
 472 PYTHON3         = python3
 473 CHECK           = sparse
 474 BASH            = bash
 475 KGZIP           = gzip
 476 KBZIP2          = bzip2
 477 KLZOP           = lzop
 478 LZMA            = lzma
 479 LZ4             = lz4c
 480 XZ              = xz
 481 ZSTD            = zstd
 482
 483 CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
 484                   -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
 485 NOSTDINC_FLAGS :=
 486 CFLAGS_MODULE   =
 487 AFLAGS_MODULE   =
 488 LDFLAGS_MODULE  =
 489 CFLAGS_KERNEL   =
 490 AFLAGS_KERNEL   =
 491 LDFLAGS_vmlinux =
 492
 493 # Prefer linux-backports-modules
 494 ifneq ($(KBUILD_SRC),)
 495 ifneq ($(shell if test -e $(KBUILD_OUTPUT)/ubuntu-build; then echo yes; fi),yes)
 496 UBUNTUINCLUDE := -I/usr/src/linux-headers-lbm-$(KERNELRELEASE)
 497 endif
 498 endif
 499
 500 # Use USERINCLUDE when you must reference the UAPI directories only.
 501 USERINCLUDE    := \
 502                 -I$(srctree)/arch/$(SRCARCH)/include/uapi \
 503                 -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
 504                 -I$(srctree)/include/uapi \
 505                 -I$(objtree)/include/generated/uapi \
 506                 -include $(srctree)/include/linux/compiler-version.h \
 507                 -include $(srctree)/include/linux/kconfig.h
 508
 509 # Use LINUXINCLUDE when you must reference the include/ directory.
 510 # Needed to be compatible with the O= option
 511 LINUXINCLUDE    := \
 512                 $(UBUNTUINCLUDE) \
 513                 -I$(srctree)/arch/$(SRCARCH)/include \
 514                 -I$(objtree)/arch/$(SRCARCH)/include/generated \
 515                 $(if $(building_out_of_srctree),-I$(srctree)/include) \
 516                 -I$(objtree)/include \
 517                 $(USERINCLUDE)
 518
 519 # UBUNTU: Include our third party driver stuff too
 520 LINUXINCLUDE   += -Iubuntu/include $(if $(KBUILD_SRC),-I$(srctree)/ubuntu/include)
 521
 522 KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
 523 KBUILD_CFLAGS   := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
 524                    -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
 525                    -Werror=implicit-function-declaration -Werror=implicit-int \
 526                    -Werror=return-type -Wno-format-security \
 527                    -std=gnu89
 528 KBUILD_CPPFLAGS := -D__KERNEL__
 529 KBUILD_AFLAGS_KERNEL :=
 530 KBUILD_CFLAGS_KERNEL :=
 531 KBUILD_AFLAGS_MODULE  := -DMODULE
 532 KBUILD_CFLAGS_MODULE  := -DMODULE
 533 KBUILD_LDFLAGS_MODULE :=
 534 KBUILD_LDFLAGS :=
 535 CLANG_FLAGS :=
 536
 537 export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC
 538 export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
 539 export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
 540 export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
 541 export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
 542
 543 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
 544 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
 545 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
 546 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
 547 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
 548
 549 # Files to ignore in find ... statements
 550
 551 export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
 552                           -name CVS -o -name .pc -o -name .hg -o -name .git \) \
 553                           -prune -o
 554 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
 555                          --exclude CVS --exclude .pc --exclude .hg --exclude .git
 556
 557 # ===========================================================================
 558 # Rules shared between *config targets and build targets
 559
 560 # Basic helpers built in scripts/basic/
 561 PHONY += scripts_basic
 562 scripts_basic:
 563         $(Q)$(MAKE) $(build)=scripts/basic
 564
 565 PHONY += outputmakefile
 566 ifdef building_out_of_srctree
 567 # Before starting out-of-tree build, make sure the source tree is clean.
 568 # outputmakefile generates a Makefile in the output directory, if using a
 569 # separate output directory. This allows convenient use of make in the
 570 # output directory.
 571 # At the same time when output Makefile generated, generate .gitignore to
 572 # ignore whole output directory
 573
 574 quiet_cmd_makefile = GEN     Makefile
 575       cmd_makefile = { \
 576         echo "\# Automatically generated by $(srctree)/Makefile: don't edit"; \
 577         echo "include $(srctree)/Makefile"; \
 578         } > Makefile
 579
 580 outputmakefile:
 581         $(Q)if [ -f $(srctree)/.config -o \
 582                  -d $(srctree)/include/config -o \
 583                  -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
 584                 echo >&2 "***"; \
 585                 echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
 586                 echo >&2 "*** in $(abs_srctree)";\
 587                 echo >&2 "***"; \
 588                 false; \
 589         fi
 590         $(Q)ln -fsn $(srctree) source
 591         $(call cmd,makefile)
 592         $(Q)test -e .gitignore || \
 593         { echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
 594 endif
 595
 596 # The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
 597 # Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
 598 # CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
 599 # and from include/config/auto.conf.cmd to detect the compiler upgrade.
 600 CC_VERSION_TEXT = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1))
 601
 602 ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
 603 include $(srctree)/scripts/Makefile.clang
 604 endif
 605
 606 # Include this also for config targets because some architectures need
 607 # cc-cross-prefix to determine CROSS_COMPILE.
 608 ifdef need-compiler
 609 include $(srctree)/scripts/Makefile.compiler
 610 endif
 611
 612 ifdef config-build
 613 # ===========================================================================
 614 # *config targets only - make sure prerequisites are updated, and descend
 615 # in scripts/kconfig to make the *config target
 616
 617 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
 618 # KBUILD_DEFCONFIG may point out an alternative default configuration
 619 # used for 'make defconfig'
 620 include $(srctree)/arch/$(SRCARCH)/Makefile
 621 export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
 622
 623 config: outputmakefile scripts_basic FORCE
 624         $(Q)$(MAKE) $(build)=scripts/kconfig $@
 625
 626 %config: outputmakefile scripts_basic FORCE
 627         $(Q)$(MAKE) $(build)=scripts/kconfig $@
 628
 629 else #!config-build
 630 # ===========================================================================
 631 # Build targets only - this includes vmlinux, arch specific targets, clean
 632 # targets and others. In general all targets except *config targets.
 633
 634 # If building an external module we do not care about the all: rule
 635 # but instead __all depend on modules
 636 PHONY += all
 637 ifeq ($(KBUILD_EXTMOD),)
 638 __all: all
 639 else
 640 __all: modules
 641 endif
 642
 643 # Decide whether to build built-in, modular, or both.
 644 # Normally, just do built-in.
 645
 646 KBUILD_MODULES :=
 647 KBUILD_BUILTIN := 1
 648
 649 # If we have only "make modules", don't compile built-in objects.
 650 ifeq ($(MAKECMDGOALS),modules)
 651   KBUILD_BUILTIN :=
 652 endif
 653
 654 # If we have "make <whatever> modules", compile modules
 655 # in addition to whatever we do anyway.
 656 # Just "make" or "make all" shall build modules as well
 657
 658 ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
 659   KBUILD_MODULES := 1
 660 endif
 661
 662 ifeq ($(MAKECMDGOALS),)
 663   KBUILD_MODULES := 1
 664 endif
 665
 666 export KBUILD_MODULES KBUILD_BUILTIN
 667
 668 ifdef need-config
 669 include include/config/auto.conf
 670 endif
 671
 672 ifeq ($(KBUILD_EXTMOD),)
 673 # Objects we will link into vmlinux / subdirs we need to visit
 674 core-y          := init/ usr/ arch/$(SRCARCH)/
 675 drivers-y       := drivers/ sound/ ubuntu/
 676 drivers-$(CONFIG_SAMPLES) += samples/
 677 drivers-$(CONFIG_NET) += net/
 678 drivers-y       += virt/
 679 libs-y          := lib/
 680 endif # KBUILD_EXTMOD
 681
 682 # The all: target is the default when no target is given on the
 683 # command line.
 684 # This allow a user to issue only 'make' to build a kernel including modules
 685 # Defaults to vmlinux, but the arch makefile usually adds further targets
 686 all: vmlinux
 687
 688 CFLAGS_GCOV     := -fprofile-arcs -ftest-coverage
 689 ifdef CONFIG_CC_IS_GCC
 690 CFLAGS_GCOV     += -fno-tree-loop-im
 691 endif
 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 ifdef CONFIG_CC_IS_GCC
 700 RETPOLINE_CFLAGS        := $(call cc-option,-mindirect-branch=thunk-extern -mindirect-branch-register)
 701 RETPOLINE_VDSO_CFLAGS   := $(call cc-option,-mindirect-branch=thunk-inline -mindirect-branch-register)
 702 endif
 703 ifdef CONFIG_CC_IS_CLANG
 704 RETPOLINE_CFLAGS        := -mretpoline-external-thunk
 705 RETPOLINE_VDSO_CFLAGS   := -mretpoline
 706 endif
 707 export RETPOLINE_CFLAGS
 708 export RETPOLINE_VDSO_CFLAGS
 709
 710 include $(srctree)/arch/$(SRCARCH)/Makefile
 711
 712 ifdef need-config
 713 ifdef may-sync-config
 714 # Read in dependencies to all Kconfig* files, make sure to run syncconfig if
 715 # changes are detected. This should be included after arch/$(SRCARCH)/Makefile
 716 # because some architectures define CROSS_COMPILE there.
 717 include include/config/auto.conf.cmd
 718
 719 $(KCONFIG_CONFIG):
 720         @echo >&2 '***'
 721         @echo >&2 '*** Configuration file "$@" not found!'
 722         @echo >&2 '***'
 723         @echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
 724         @echo >&2 '*** "make menuconfig" or "make xconfig").'
 725         @echo >&2 '***'
 726         @/bin/false
 727
 728 # The actual configuration files used during the build are stored in
 729 # include/generated/ and include/config/. Update them if .config is newer than
 730 # include/config/auto.conf (which mirrors .config).
 731 #
 732 # This exploits the 'multi-target pattern rule' trick.
 733 # The syncconfig should be executed only once to make all the targets.
 734 # (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
 735 #
 736 # Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
 737 # so you cannot notice that Kconfig is waiting for the user input.
 738 %/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h: $(KCONFIG_CONFIG)
 739         $(Q)$(kecho) "  SYNC    $@"
 740         $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
 741 else # !may-sync-config
 742 # External modules and some install targets need include/generated/autoconf.h
 743 # and include/config/auto.conf but do not care if they are up-to-date.
 744 # Use auto.conf to trigger the test
 745 PHONY += include/config/auto.conf
 746
 747 include/config/auto.conf:
 748         $(Q)test -e include/generated/autoconf.h -a -e $@ || (          \
 749         echo >&2;                                                       \
 750         echo >&2 "  ERROR: Kernel configuration is invalid.";           \
 751         echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
 752         echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";      \
 753         echo >&2 ;                                                      \
 754         /bin/false)
 755
 756 endif # may-sync-config
 757 endif # need-config
 758
 759 KBUILD_CFLAGS   += -fno-delete-null-pointer-checks
 760 KBUILD_CFLAGS   += $(call cc-disable-warning,frame-address,)
 761 KBUILD_CFLAGS   += $(call cc-disable-warning, format-truncation)
 762 KBUILD_CFLAGS   += $(call cc-disable-warning, format-overflow)
 763 KBUILD_CFLAGS   += $(call cc-disable-warning, address-of-packed-member)
 764
 765 ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
 766 KBUILD_CFLAGS += -O2
 767 else ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3
 768 KBUILD_CFLAGS += -O3
 769 else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
 770 KBUILD_CFLAGS += -Os
 771 endif
 772
 773 # Tell gcc to never replace conditional load with a non-conditional one
 774 ifdef CONFIG_CC_IS_GCC
 775 # gcc-10 renamed --param=allow-store-data-races=0 to
 776 # -fno-allow-store-data-races.
 777 KBUILD_CFLAGS   += $(call cc-option,--param=allow-store-data-races=0)
 778 KBUILD_CFLAGS   += $(call cc-option,-fno-allow-store-data-races)
 779 endif
 780
 781 ifdef CONFIG_READABLE_ASM
 782 # Disable optimizations that make assembler listings hard to read.
 783 # reorder blocks reorders the control in the function
 784 # ipa clone creates specialized cloned functions
 785 # partial inlining inlines only parts of functions
 786 KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
 787 endif
 788
 789 ifneq ($(CONFIG_FRAME_WARN),0)
 790 KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
 791 endif
 792
 793 stackp-flags-y                                    := -fno-stack-protector
 794 stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
 795 stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
 796
 797 KBUILD_CFLAGS += $(stackp-flags-y)
 798
 799 KBUILD_CFLAGS-$(CONFIG_WERROR) += -Werror
 800 KBUILD_CFLAGS += $(KBUILD_CFLAGS-y)
 801
 802 ifdef CONFIG_CC_IS_CLANG
 803 KBUILD_CPPFLAGS += -Qunused-arguments
 804 # The kernel builds with '-std=gnu89' so use of GNU extensions is acceptable.
 805 KBUILD_CFLAGS += -Wno-gnu
 806 # CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
 807 # source of a reference will be _MergedGlobals and not on of the whitelisted names.
 808 # See modpost pattern 2
 809 KBUILD_CFLAGS += -mno-global-merge
 810 else
 811
 812 # Warn about unmarked fall-throughs in switch statement.
 813 # Disabled for clang while comment to attribute conversion happens and
 814 # https://github.com/ClangBuiltLinux/linux/issues/636 is discussed.
 815 KBUILD_CFLAGS += $(call cc-option,-Wimplicit-fallthrough=5,)
 816 # gcc inanely warns about local variables called 'main'
 817 KBUILD_CFLAGS += -Wno-main
 818 endif
 819
 820 # These warnings generated too much noise in a regular build.
 821 # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
 822 KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
 823 KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
 824
 825 ifdef CONFIG_FRAME_POINTER
 826 KBUILD_CFLAGS   += -fno-omit-frame-pointer -fno-optimize-sibling-calls
 827 else
 828 # Some targets (ARM with Thumb2, for example), can't be built with frame
 829 # pointers.  For those, we don't have FUNCTION_TRACER automatically
 830 # select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
 831 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
 832 # -fomit-frame-pointer with FUNCTION_TRACER.
 833 ifndef CONFIG_FUNCTION_TRACER
 834 KBUILD_CFLAGS   += -fomit-frame-pointer
 835 endif
 836 endif
 837
 838 # Initialize all stack variables with a 0xAA pattern.
 839 ifdef CONFIG_INIT_STACK_ALL_PATTERN
 840 KBUILD_CFLAGS   += -ftrivial-auto-var-init=pattern
 841 endif
 842
 843 # Initialize all stack variables with a zero value.
 844 ifdef CONFIG_INIT_STACK_ALL_ZERO
 845 # Future support for zero initialization is still being debated, see
 846 # https://bugs.llvm.org/show_bug.cgi?id=45497. These flags are subject to being
 847 # renamed or dropped.
 848 KBUILD_CFLAGS   += -ftrivial-auto-var-init=zero
 849 KBUILD_CFLAGS   += -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
 850 endif
 851
 852 # While VLAs have been removed, GCC produces unreachable stack probes
 853 # for the randomize_kstack_offset feature. Disable it for all compilers.
 854 KBUILD_CFLAGS   += $(call cc-option, -fno-stack-clash-protection)
 855
 856 # Clear used registers at func exit (to reduce data lifetime and ROP gadgets).
 857 ifdef CONFIG_ZERO_CALL_USED_REGS
 858 KBUILD_CFLAGS   += -fzero-call-used-regs=used-gpr
 859 endif
 860
 861 DEBUG_CFLAGS    :=
 862
 863 ifdef CONFIG_DEBUG_INFO
 864
 865 ifdef CONFIG_DEBUG_INFO_SPLIT
 866 DEBUG_CFLAGS    += -gsplit-dwarf
 867 else
 868 DEBUG_CFLAGS    += -g
 869 endif
 870
 871 ifndef CONFIG_AS_IS_LLVM
 872 KBUILD_AFLAGS   += -Wa,-gdwarf-2
 873 endif
 874
 875 ifndef CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT
 876 dwarf-version-$(CONFIG_DEBUG_INFO_DWARF4) := 4
 877 dwarf-version-$(CONFIG_DEBUG_INFO_DWARF5) := 5
 878 DEBUG_CFLAGS    += -gdwarf-$(dwarf-version-y)
 879 endif
 880
 881 ifdef CONFIG_DEBUG_INFO_REDUCED
 882 DEBUG_CFLAGS    += -fno-var-tracking
 883 ifdef CONFIG_CC_IS_GCC
 884 DEBUG_CFLAGS    += -femit-struct-debug-baseonly
 885 endif
 886 endif
 887
 888 ifdef CONFIG_DEBUG_INFO_COMPRESSED
 889 DEBUG_CFLAGS    += -gz=zlib
 890 KBUILD_AFLAGS   += -gz=zlib
 891 KBUILD_LDFLAGS  += --compress-debug-sections=zlib
 892 endif
 893
 894 endif # CONFIG_DEBUG_INFO
 895
 896 KBUILD_CFLAGS += $(DEBUG_CFLAGS)
 897 export DEBUG_CFLAGS
 898
 899 ifdef CONFIG_FUNCTION_TRACER
 900 ifdef CONFIG_FTRACE_MCOUNT_USE_CC
 901   CC_FLAGS_FTRACE       += -mrecord-mcount
 902   ifdef CONFIG_HAVE_NOP_MCOUNT
 903     ifeq ($(call cc-option-yn, -mnop-mcount),y)
 904       CC_FLAGS_FTRACE   += -mnop-mcount
 905       CC_FLAGS_USING    += -DCC_USING_NOP_MCOUNT
 906     endif
 907   endif
 908 endif
 909 ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
 910   CC_FLAGS_USING        += -DCC_USING_NOP_MCOUNT
 911 endif
 912 ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
 913   ifdef CONFIG_HAVE_C_RECORDMCOUNT
 914     BUILD_C_RECORDMCOUNT := y
 915     export BUILD_C_RECORDMCOUNT
 916   endif
 917 endif
 918 ifdef CONFIG_HAVE_FENTRY
 919   # s390-linux-gnu-gcc did not support -mfentry until gcc-9.
 920   ifeq ($(call cc-option-yn, -mfentry),y)
 921     CC_FLAGS_FTRACE     += -mfentry
 922     CC_FLAGS_USING      += -DCC_USING_FENTRY
 923   endif
 924 endif
 925 export CC_FLAGS_FTRACE
 926 KBUILD_CFLAGS   += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
 927 KBUILD_AFLAGS   += $(CC_FLAGS_USING)
 928 endif
 929
 930 # We trigger additional mismatches with less inlining
 931 ifdef CONFIG_DEBUG_SECTION_MISMATCH
 932 KBUILD_CFLAGS += -fno-inline-functions-called-once
 933 endif
 934
 935 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
 936 KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
 937 LDFLAGS_vmlinux += --gc-sections
 938 endif
 939
 940 ifdef CONFIG_SHADOW_CALL_STACK
 941 CC_FLAGS_SCS    := -fsanitize=shadow-call-stack
 942 KBUILD_CFLAGS   += $(CC_FLAGS_SCS)
 943 export CC_FLAGS_SCS
 944 endif
 945
 946 ifdef CONFIG_LTO_CLANG
 947 ifdef CONFIG_LTO_CLANG_THIN
 948 CC_FLAGS_LTO    := -flto=thin -fsplit-lto-unit
 949 KBUILD_LDFLAGS  += --thinlto-cache-dir=$(extmod_prefix).thinlto-cache
 950 else
 951 CC_FLAGS_LTO    := -flto
 952 endif
 953 CC_FLAGS_LTO    += -fvisibility=hidden
 954
 955 # Limit inlining across translation units to reduce binary size
 956 KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
 957
 958 # Check for frame size exceeding threshold during prolog/epilog insertion
 959 # when using lld < 13.0.0.
 960 ifneq ($(CONFIG_FRAME_WARN),0)
 961 ifeq ($(shell test $(CONFIG_LLD_VERSION) -lt 130000; echo $$?),0)
 962 KBUILD_LDFLAGS  += -plugin-opt=-warn-stack-size=$(CONFIG_FRAME_WARN)
 963 endif
 964 endif
 965 endif
 966
 967 ifdef CONFIG_LTO
 968 KBUILD_CFLAGS   += -fno-lto $(CC_FLAGS_LTO)
 969 KBUILD_AFLAGS   += -fno-lto
 970 export CC_FLAGS_LTO
 971 endif
 972
 973 ifdef CONFIG_CFI_CLANG
 974 CC_FLAGS_CFI    := -fsanitize=cfi \
 975                    -fsanitize-cfi-cross-dso \
 976                    -fno-sanitize-cfi-canonical-jump-tables \
 977                    -fno-sanitize-trap=cfi \
 978                    -fno-sanitize-blacklist
 979
 980 ifdef CONFIG_CFI_PERMISSIVE
 981 CC_FLAGS_CFI    += -fsanitize-recover=cfi
 982 endif
 983
 984 # If LTO flags are filtered out, we must also filter out CFI.
 985 CC_FLAGS_LTO    += $(CC_FLAGS_CFI)
 986 KBUILD_CFLAGS   += $(CC_FLAGS_CFI)
 987 export CC_FLAGS_CFI
 988 endif
 989
 990 ifdef CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_64B
 991 KBUILD_CFLAGS += -falign-functions=64
 992 endif
 993
 994 # arch Makefile may override CC so keep this after arch Makefile is included
 995 NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
 996
 997 # warn about C99 declaration after statement
 998 KBUILD_CFLAGS += -Wdeclaration-after-statement
 999
1000 # Variable Length Arrays (VLAs) should not be used anywhere in the kernel
1001 KBUILD_CFLAGS += -Wvla
1002
1003 # disable pointer signed / unsigned warnings in gcc 4.0
1004 KBUILD_CFLAGS += -Wno-pointer-sign
1005
1006 # disable stringop warnings in gcc 8+
1007 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
1008
1009 # We'll want to enable this eventually, but it's not going away for 5.7 at least
1010 KBUILD_CFLAGS += $(call cc-disable-warning, zero-length-bounds)
1011 KBUILD_CFLAGS += -Wno-array-bounds
1012 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
1013
1014 # Another good warning that we'll want to enable eventually
1015 KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
1016
1017 # Enabled with W=2, disabled by default as noisy
1018 ifdef CONFIG_CC_IS_GCC
1019 KBUILD_CFLAGS += -Wno-maybe-uninitialized
1020 endif
1021
1022 # disable invalid "can't wrap" optimizations for signed / pointers
1023 KBUILD_CFLAGS   += -fno-strict-overflow
1024
1025 # Make sure -fstack-check isn't enabled (like gentoo apparently did)
1026 KBUILD_CFLAGS  += -fno-stack-check
1027
1028 # conserve stack if available
1029 ifdef CONFIG_CC_IS_GCC
1030 KBUILD_CFLAGS   += -fconserve-stack
1031 endif
1032
1033 # Prohibit date/time macros, which would make the build non-deterministic
1034 KBUILD_CFLAGS   += -Werror=date-time
1035
1036 # enforce correct pointer usage
1037 KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)
1038
1039 # Require designated initializers for all marked structures
1040 KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)
1041
1042 # change __FILE__ to the relative path from the srctree
1043 KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
1044
1045 # include additional Makefiles when needed
1046 include-y                       := scripts/Makefile.extrawarn
1047 include-$(CONFIG_KASAN)         += scripts/Makefile.kasan
1048 include-$(CONFIG_KCSAN)         += scripts/Makefile.kcsan
1049 include-$(CONFIG_UBSAN)         += scripts/Makefile.ubsan
1050 include-$(CONFIG_KCOV)          += scripts/Makefile.kcov
1051 include-$(CONFIG_GCC_PLUGINS)   += scripts/Makefile.gcc-plugins
1052
1053 include $(addprefix $(srctree)/, $(include-y))
1054
1055 # scripts/Makefile.gcc-plugins is intentionally included last.
1056 # Do not add $(call cc-option,...) below this line. When you build the kernel
1057 # from the clean source tree, the GCC plugins do not exist at this point.
1058
1059 # Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
1060 KBUILD_CPPFLAGS += $(KCPPFLAGS)
1061 KBUILD_AFLAGS   += $(KAFLAGS)
1062 KBUILD_CFLAGS   += $(KCFLAGS)
1063
1064 KBUILD_LDFLAGS_MODULE += --build-id=sha1
1065 LDFLAGS_vmlinux += --build-id=sha1
1066
1067 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1068 LDFLAGS_vmlinux += $(call ld-option, -X,)
1069 endif
1070
1071 ifeq ($(CONFIG_RELR),y)
1072 LDFLAGS_vmlinux += --pack-dyn-relocs=relr --use-android-relr-tags
1073 endif
1074
1075 # We never want expected sections to be placed heuristically by the
1076 # linker. All sections should be explicitly named in the linker script.
1077 ifdef CONFIG_LD_ORPHAN_WARN
1078 LDFLAGS_vmlinux += --orphan-handling=warn
1079 endif
1080
1081 # Align the bit size of userspace programs with the kernel
1082 KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1083 KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1084
1085 # make the checker run with the right architecture
1086 CHECKFLAGS += --arch=$(ARCH)
1087
1088 # insure the checker run with the right endianness
1089 CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1090
1091 # the checker needs the correct machine size
1092 CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1093
1094 # Default kernel image to build when no specific target is given.
1095 # KBUILD_IMAGE may be overruled on the command line or
1096 # set in the environment
1097 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
1098 # this default value
1099 export KBUILD_IMAGE ?= vmlinux
1100
1101 #
1102 # INSTALL_PATH specifies where to place the updated kernel and system map
1103 # images. Default is /boot, but you can set it to other values
1104 export  INSTALL_PATH ?= /boot
1105
1106 #
1107 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1108 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1109 # an argument if needed. Otherwise it defaults to the kernel install path
1110 #
1111 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1112
1113 #
1114 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1115 # relocations required by build roots.  This is not defined in the
1116 # makefile but the argument can be passed to make if needed.
1117 #
1118
1119 MODLIB  = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1120 export MODLIB
1121
1122 PHONY += prepare0
1123
1124 export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
1125 export MODORDER := $(extmod_prefix)modules.order
1126 export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
1127
1128 ifeq ($(KBUILD_EXTMOD),)
1129 core-y          += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
1130
1131 vmlinux-dirs    := $(patsubst %/,%,$(filter %/, \
1132                      $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
1133                      $(libs-y) $(libs-m)))
1134
1135 vmlinux-alldirs := $(sort $(vmlinux-dirs) Documentation \
1136                      $(patsubst %/,%,$(filter %/, $(core-) \
1137                         $(drivers-) $(libs-))))
1138
1139 subdir-modorder := $(addsuffix modules.order,$(filter %/, \
1140                         $(core-y) $(core-m) $(libs-y) $(libs-m) \
1141                         $(drivers-y) $(drivers-m)))
1142
1143 build-dirs      := $(vmlinux-dirs)
1144 clean-dirs      := $(vmlinux-alldirs)
1145
1146 # Externally visible symbols (used by link-vmlinux.sh)
1147 KBUILD_VMLINUX_OBJS := $(head-y) $(patsubst %/,%/built-in.a, $(core-y))
1148 KBUILD_VMLINUX_OBJS += $(addsuffix built-in.a, $(filter %/, $(libs-y)))
1149 ifdef CONFIG_MODULES
1150 KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1151 KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1152 else
1153 KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1154 endif
1155 KBUILD_VMLINUX_OBJS += $(patsubst %/,%/built-in.a, $(drivers-y))
1156
1157 export KBUILD_VMLINUX_OBJS KBUILD_VMLINUX_LIBS
1158 export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1159 # used by scripts/Makefile.package
1160 export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) LICENSES arch include scripts tools)
1161
1162 vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
1163
1164 # Recurse until adjust_autoksyms.sh is satisfied
1165 PHONY += autoksyms_recursive
1166 ifdef CONFIG_TRIM_UNUSED_KSYMS
1167 # For the kernel to actually contain only the needed exported symbols,
1168 # we have to build modules as well to determine what those symbols are.
1169 # (this can be evaluated only once include/config/auto.conf has been included)
1170 KBUILD_MODULES := 1
1171
1172 autoksyms_recursive: descend modules.order
1173         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1174           "$(MAKE) -f $(srctree)/Makefile vmlinux"
1175 endif
1176
1177 autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1178
1179 quiet_cmd_autoksyms_h = GEN     $@
1180       cmd_autoksyms_h = mkdir -p $(dir $@); \
1181                         $(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@
1182
1183 $(autoksyms_h):
1184         $(call cmd,autoksyms_h)
1185
1186 ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1187
1188 # Final link of vmlinux with optional arch pass after final link
1189 cmd_link-vmlinux =                                                 \
1190         $(CONFIG_SHELL) $< "$(LD)" "$(KBUILD_LDFLAGS)" "$(LDFLAGS_vmlinux)";    \
1191         $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1192
1193 vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1194         +$(call if_changed_dep,link-vmlinux)
1195
1196 targets := vmlinux
1197
1198 # The actual objects are generated when descending,
1199 # make sure no implicit rule kicks in
1200 $(sort $(vmlinux-deps) $(subdir-modorder)): descend ;
1201
1202 filechk_kernel.release = \
1203         echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1204
1205 # Store (new) KERNELRELEASE string in include/config/kernel.release
1206 include/config/kernel.release: FORCE
1207         $(call filechk,kernel.release)
1208
1209 # Additional helpers built in scripts/
1210 # Carefully list dependencies so we do not try to build scripts twice
1211 # in parallel
1212 PHONY += scripts
1213 scripts: scripts_basic scripts_dtc
1214         $(Q)$(MAKE) $(build)=$(@)
1215
1216 # Things we need to do before we recursively start building the kernel
1217 # or the modules are listed in "prepare".
1218 # A multi level approach is used. prepareN is processed before prepareN-1.
1219 # archprepare is used in arch Makefiles and when processed asm symlink,
1220 # version.h and scripts_basic is processed / created.
1221
1222 PHONY += prepare archprepare
1223
1224 archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1225         asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h \
1226         include/generated/autoconf.h remove-stale-files
1227
1228 prepare0: archprepare
1229         $(Q)$(MAKE) $(build)=scripts/mod
1230         $(Q)$(MAKE) $(build)=.
1231
1232 # All the preparing..
1233 prepare: prepare0
1234
1235 PHONY += remove-stale-files
1236 remove-stale-files:
1237         $(Q)$(srctree)/scripts/remove-stale-files
1238
1239 # Support for using generic headers in asm-generic
1240 asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1241
1242 PHONY += asm-generic uapi-asm-generic
1243 asm-generic: uapi-asm-generic
1244         $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1245         generic=include/asm-generic
1246 uapi-asm-generic:
1247         $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1248         generic=include/uapi/asm-generic
1249
1250 # Generate some files
1251 # ---------------------------------------------------------------------------
1252
1253 # KERNELRELEASE can change from a few different places, meaning version.h
1254 # needs to be updated, so this check is forced on all builds
1255
1256 uts_len := 64
1257 define filechk_utsrelease.h
1258         if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1259           echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1260           exit 1;                                                         \
1261         fi;                                                               \
1262         echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1263 endef
1264
1265 define filechk_version.h
1266         if [ $(SUBLEVEL) -gt 255 ]; then                                 \
1267                 echo \#define LINUX_VERSION_CODE $(shell                 \
1268                 expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1269         else                                                             \
1270                 echo \#define LINUX_VERSION_CODE $(shell                 \
1271                 expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1272         fi;                                                              \
1273         echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
1274         ((c) > 255 ? 255 : (c)))';                                       \
1275         echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
1276         echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
1277         echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1278 endef
1279
1280 $(version_h): PATCHLEVEL := $(if $(PATCHLEVEL), $(PATCHLEVEL), 0)
1281 $(version_h): SUBLEVEL := $(if $(SUBLEVEL), $(SUBLEVEL), 0)
1282 $(version_h): FORCE
1283         $(call filechk,version.h)
1284
1285 include/generated/utsrelease.h: include/config/kernel.release FORCE
1286         $(call filechk,utsrelease.h)
1287
1288 PHONY += headerdep
1289 headerdep:
1290         $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1291         $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1292
1293 # ---------------------------------------------------------------------------
1294 # Kernel headers
1295
1296 #Default location for installed headers
1297 export INSTALL_HDR_PATH = $(objtree)/usr
1298
1299 quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1300       cmd_headers_install = \
1301         mkdir -p $(INSTALL_HDR_PATH); \
1302         rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1303         usr/include $(INSTALL_HDR_PATH)
1304
1305 PHONY += headers_install
1306 headers_install: headers
1307         $(call cmd,headers_install)
1308
1309 PHONY += archheaders archscripts
1310
1311 hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1312
1313 PHONY += headers
1314 headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1315         $(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1316           $(error Headers not exportable for the $(SRCARCH) architecture))
1317         $(Q)$(MAKE) $(hdr-inst)=include/uapi
1318         $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1319         $(Q)$(MAKE) $(hdr-inst)=ubuntu/include dst=include oldheaders=
1320
1321 # Deprecated. It is no-op now.
1322 PHONY += headers_check
1323 headers_check:
1324         @echo >&2 "=================== WARNING ==================="
1325         @echo >&2 "Since Linux 5.5, 'make headers_check' is no-op,"
1326         @echo >&2 "and will be removed after Linux 5.15 release."
1327         @echo >&2 "Please remove headers_check from your scripts."
1328         @echo >&2 "==============================================="
1329
1330 ifdef CONFIG_HEADERS_INSTALL
1331 prepare: headers
1332 endif
1333
1334 PHONY += scripts_unifdef
1335 scripts_unifdef: scripts_basic
1336         $(Q)$(MAKE) $(build)=scripts scripts/unifdef
1337
1338 # ---------------------------------------------------------------------------
1339 # Install
1340
1341 # Many distributions have the custom install script, /sbin/installkernel.
1342 # If DKMS is installed, 'make install' will eventually recuses back
1343 # to the this Makefile to build and install external modules.
1344 # Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
1345
1346 install: sub_make_done :=
1347
1348 # ---------------------------------------------------------------------------
1349 # Tools
1350
1351 ifdef CONFIG_STACK_VALIDATION
1352 prepare: tools/objtool
1353 endif
1354
1355 ifdef CONFIG_BPF
1356 ifdef CONFIG_DEBUG_INFO_BTF
1357 prepare: tools/bpf/resolve_btfids
1358 endif
1359 endif
1360
1361 PHONY += resolve_btfids_clean
1362
1363 resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1364
1365 # tools/bpf/resolve_btfids directory might not exist
1366 # in output directory, skip its clean in that case
1367 resolve_btfids_clean:
1368 ifneq ($(wildcard $(resolve_btfids_O)),)
1369         $(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1370 endif
1371
1372 # Clear a bunch of variables before executing the submake
1373 ifeq ($(quiet),silent_)
1374 tools_silent=s
1375 endif
1376
1377 tools/: FORCE
1378         $(Q)mkdir -p $(objtree)/tools
1379         $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1380
1381 tools/%: FORCE
1382         $(Q)mkdir -p $(objtree)/tools
1383         $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1384
1385 # ---------------------------------------------------------------------------
1386 # Kernel selftest
1387
1388 PHONY += kselftest
1389 kselftest:
1390         $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1391
1392 kselftest-%: FORCE
1393         $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1394
1395 PHONY += kselftest-merge
1396 kselftest-merge:
1397         $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1398         $(Q)find $(srctree)/tools/testing/selftests -name config | \
1399                 xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1400         $(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1401
1402 # ---------------------------------------------------------------------------
1403 # Devicetree files
1404
1405 ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1406 dtstree := arch/$(SRCARCH)/boot/dts
1407 endif
1408
1409 ifneq ($(dtstree),)
1410
1411 %.dtb: include/config/kernel.release scripts_dtc
1412         $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1413
1414 %.dtbo: include/config/kernel.release scripts_dtc
1415         $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1416
1417 PHONY += dtbs dtbs_install dtbs_check
1418 dtbs: include/config/kernel.release scripts_dtc
1419         $(Q)$(MAKE) $(build)=$(dtstree)
1420
1421 ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1422 export CHECK_DTBS=y
1423 dtbs: dt_binding_check
1424 endif
1425
1426 dtbs_check: dtbs
1427
1428 dtbs_install:
1429         $(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1430
1431 ifdef CONFIG_OF_EARLY_FLATTREE
1432 all: dtbs
1433 endif
1434
1435 endif
1436
1437 PHONY += scripts_dtc
1438 scripts_dtc: scripts_basic
1439         $(Q)$(MAKE) $(build)=scripts/dtc
1440
1441 ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1442 export CHECK_DT_BINDING=y
1443 endif
1444
1445 PHONY += dt_binding_check
1446 dt_binding_check: scripts_dtc
1447         $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1448
1449 # ---------------------------------------------------------------------------
1450 # Modules
1451
1452 ifdef CONFIG_MODULES
1453
1454 # By default, build modules as well
1455
1456 all: modules
1457
1458 # When we're building modules with modversions, we need to consider
1459 # the built-in objects during the descend as well, in order to
1460 # make sure the checksums are up to date before we record them.
1461 ifdef CONFIG_MODVERSIONS
1462   KBUILD_BUILTIN := 1
1463 endif
1464
1465 # Build modules
1466 #
1467 # A module can be listed more than once in obj-m resulting in
1468 # duplicate lines in modules.order files.  Those are removed
1469 # using awk while concatenating to the final file.
1470
1471 PHONY += modules
1472 modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_check modules_prepare
1473
1474 cmd_modules_order = $(AWK) '!x[$$0]++' $(real-prereqs) > $@
1475
1476 modules.order: $(subdir-modorder) FORCE
1477         $(call if_changed,modules_order)
1478
1479 targets += modules.order
1480
1481 # Target to prepare building external modules
1482 PHONY += modules_prepare
1483 modules_prepare: prepare
1484         $(Q)$(MAKE) $(build)=scripts scripts/module.lds
1485
1486 export modules_sign_only :=
1487
1488 ifeq ($(CONFIG_MODULE_SIG),y)
1489 PHONY += modules_sign
1490 modules_sign: modules_install
1491         @:
1492
1493 # modules_sign is a subset of modules_install.
1494 # 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1495 ifeq ($(filter modules_install,$(MAKECMDGOALS)),)
1496 modules_sign_only := y
1497 endif
1498 endif
1499
1500 modinst_pre :=
1501 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
1502 modinst_pre := __modinst_pre
1503 endif
1504
1505 modules_install: $(modinst_pre)
1506 PHONY += __modinst_pre
1507 __modinst_pre:
1508         @rm -rf $(MODLIB)/kernel
1509         @rm -f $(MODLIB)/source
1510         @mkdir -p $(MODLIB)/kernel
1511         @ln -s $(abspath $(srctree)) $(MODLIB)/source
1512         @if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
1513                 rm -f $(MODLIB)/build ; \
1514                 ln -s $(CURDIR) $(MODLIB)/build ; \
1515         fi
1516         @sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order
1517         @cp -f modules.builtin $(MODLIB)/
1518         @cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
1519
1520 endif # CONFIG_MODULES
1521
1522 ###
1523 # Cleaning is done on three levels.
1524 # make clean     Delete most generated files
1525 #                Leave enough to build external modules
1526 # make mrproper  Delete the current configuration, and all generated files
1527 # make distclean Remove editor backup files, patch leftover files and the like
1528
1529 # Directories & files removed with 'make clean'
1530 CLEAN_FILES += include/ksym vmlinux.symvers modules-only.symvers \
1531                modules.builtin modules.builtin.modinfo modules.nsdeps \
1532                compile_commands.json .thinlto-cache
1533
1534 # Directories & files removed with 'make mrproper'
1535 MRPROPER_FILES += include/config include/generated          \
1536                   arch/$(SRCARCH)/include/generated .tmp_objdiff \
1537                   debian snap tar-install \
1538                   .config .config.old .version \
1539                   Module.symvers \
1540                   certs/signing_key.pem certs/signing_key.x509 \
1541                   certs/x509.genkey \
1542                   vmlinux-gdb.py \
1543                   *.spec
1544
1545 # clean - Delete most, but leave enough to build external modules
1546 #
1547 clean: rm-files := $(CLEAN_FILES)
1548
1549 PHONY += archclean vmlinuxclean
1550
1551 vmlinuxclean:
1552         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1553         $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1554
1555 clean: archclean vmlinuxclean resolve_btfids_clean
1556
1557 # mrproper - Delete all generated files, including .config
1558 #
1559 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1560 mrproper-dirs      := $(addprefix _mrproper_,scripts)
1561
1562 PHONY += $(mrproper-dirs) mrproper
1563 $(mrproper-dirs):
1564         $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1565
1566 mrproper: clean $(mrproper-dirs)
1567         $(call cmd,rmfiles)
1568
1569 # distclean
1570 #
1571 PHONY += distclean
1572
1573 distclean: mrproper
1574         @find . $(RCS_FIND_IGNORE) \
1575                 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1576                 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1577                 -o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1578                 -o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1579                 -type f -print | xargs rm -f
1580
1581
1582 # Packaging of the kernel to various formats
1583 # ---------------------------------------------------------------------------
1584
1585 %src-pkg: FORCE
1586         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1587 %pkg: include/config/kernel.release FORCE
1588         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1589
1590 # Brief documentation of the typical targets used
1591 # ---------------------------------------------------------------------------
1592
1593 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1594 boards := $(sort $(notdir $(boards)))
1595 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1596 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1597
1598 PHONY += help
1599 help:
1600         @echo  'Cleaning targets:'
1601         @echo  '  clean           - Remove most generated files but keep the config and'
1602         @echo  '                    enough build support to build external modules'
1603         @echo  '  mrproper        - Remove all generated files + config + various backup files'
1604         @echo  '  distclean       - mrproper + remove editor backup and patch files'
1605         @echo  ''
1606         @echo  'Configuration targets:'
1607         @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1608         @echo  ''
1609         @echo  'Other generic targets:'
1610         @echo  '  all             - Build all targets marked with [*]'
1611         @echo  '* vmlinux         - Build the bare kernel'
1612         @echo  '* modules         - Build all modules'
1613         @echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1614         @echo  '  dir/            - Build all files in dir and below'
1615         @echo  '  dir/file.[ois]  - Build specified target only'
1616         @echo  '  dir/file.ll     - Build the LLVM assembly file'
1617         @echo  '                    (requires compiler support for LLVM assembly generation)'
1618         @echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1619         @echo  '                    (requires a recent binutils and recent build (System.map))'
1620         @echo  '  dir/file.ko     - Build module including final link'
1621         @echo  '  modules_prepare - Set up for building external modules'
1622         @echo  '  tags/TAGS       - Generate tags file for editors'
1623         @echo  '  cscope          - Generate cscope index'
1624         @echo  '  gtags           - Generate GNU GLOBAL index'
1625         @echo  '  kernelrelease   - Output the release version string (use with make -s)'
1626         @echo  '  kernelversion   - Output the version stored in Makefile (use with make -s)'
1627         @echo  '  image_name      - Output the image name (use with make -s)'
1628         @echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1629          echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1630          echo  ''
1631         @echo  'Static analysers:'
1632         @echo  '  checkstack      - Generate a list of stack hogs'
1633         @echo  '  versioncheck    - Sanity check on version.h usage'
1634         @echo  '  includecheck    - Check for duplicate included header files'
1635         @echo  '  export_report   - List the usages of all exported symbols'
1636         @echo  '  headerdep       - Detect inclusion cycles in headers'
1637         @echo  '  coccicheck      - Check with Coccinelle'
1638         @echo  '  clang-analyzer  - Check with clang static analyzer'
1639         @echo  '  clang-tidy      - Check with clang-tidy'
1640         @echo  ''
1641         @echo  'Tools:'
1642         @echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1643         @echo  ''
1644         @echo  'Kernel selftest:'
1645         @echo  '  kselftest         - Build and run kernel selftest'
1646         @echo  '                      Build, install, and boot kernel before'
1647         @echo  '                      running kselftest on it'
1648         @echo  '                      Run as root for full coverage'
1649         @echo  '  kselftest-all     - Build kernel selftest'
1650         @echo  '  kselftest-install - Build and install kernel selftest'
1651         @echo  '  kselftest-clean   - Remove all generated kselftest files'
1652         @echo  '  kselftest-merge   - Merge all the config dependencies of'
1653         @echo  '                      kselftest to existing .config.'
1654         @echo  ''
1655         @$(if $(dtstree), \
1656                 echo 'Devicetree:'; \
1657                 echo '* dtbs             - Build device tree blobs for enabled boards'; \
1658                 echo '  dtbs_install     - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1659                 echo '  dt_binding_check - Validate device tree binding documents'; \
1660                 echo '  dtbs_check       - Validate device tree source files';\
1661                 echo '')
1662
1663         @echo 'Userspace tools targets:'
1664         @echo '  use "make tools/help"'
1665         @echo '  or  "cd tools; make help"'
1666         @echo  ''
1667         @echo  'Kernel packaging:'
1668         @$(MAKE) -f $(srctree)/scripts/Makefile.package help
1669         @echo  ''
1670         @echo  'Documentation targets:'
1671         @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1672         @echo  ''
1673         @echo  'Architecture specific targets ($(SRCARCH)):'
1674         @$(if $(archhelp),$(archhelp),\
1675                 echo '  No architecture specific help defined for $(SRCARCH)')
1676         @echo  ''
1677         @$(if $(boards), \
1678                 $(foreach b, $(boards), \
1679                 printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1680                 echo '')
1681         @$(if $(board-dirs), \
1682                 $(foreach b, $(board-dirs), \
1683                 printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1684                 printf "  %-16s - Show all of the above\\n" help-boards; \
1685                 echo '')
1686
1687         @echo  '  make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1688         @echo  '  make V=2   [targets] 2 => give reason for rebuild of target'
1689         @echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1690         @echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1691         @echo  '                       (sparse by default)'
1692         @echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1693         @echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1694         @echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
1695         @echo  '                1: warnings which may be relevant and do not occur too often'
1696         @echo  '                2: warnings which occur quite often but may still be relevant'
1697         @echo  '                3: more obscure warnings, can most likely be ignored'
1698         @echo  '                Multiple levels can be combined with W=12 or W=123'
1699         @echo  ''
1700         @echo  'Execute "make" or "make all" to build all targets marked with [*] '
1701         @echo  'For further info see the ./README file'
1702
1703
1704 help-board-dirs := $(addprefix help-,$(board-dirs))
1705
1706 help-boards: $(help-board-dirs)
1707
1708 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1709
1710 $(help-board-dirs): help-%:
1711         @echo  'Architecture specific targets ($(SRCARCH) $*):'
1712         @$(if $(boards-per-dir), \
1713                 $(foreach b, $(boards-per-dir), \
1714                 printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1715                 echo '')
1716
1717
1718 # Documentation targets
1719 # ---------------------------------------------------------------------------
1720 DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1721                linkcheckdocs dochelp refcheckdocs
1722 PHONY += $(DOC_TARGETS)
1723 $(DOC_TARGETS):
1724         $(Q)$(MAKE) $(build)=Documentation $@
1725
1726 # Misc
1727 # ---------------------------------------------------------------------------
1728
1729 PHONY += scripts_gdb
1730 scripts_gdb: prepare0
1731         $(Q)$(MAKE) $(build)=scripts/gdb
1732         $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1733
1734 ifdef CONFIG_GDB_SCRIPTS
1735 all: scripts_gdb
1736 endif
1737
1738 else # KBUILD_EXTMOD
1739
1740 ###
1741 # External module support.
1742 # When building external modules the kernel used as basis is considered
1743 # read-only, and no consistency checks are made and the make
1744 # system is not used on the basis kernel. If updates are required
1745 # in the basis kernel ordinary make commands (without M=...) must be used.
1746
1747 # We are always building only modules.
1748 KBUILD_BUILTIN :=
1749 KBUILD_MODULES := 1
1750
1751 build-dirs := $(KBUILD_EXTMOD)
1752 $(MODORDER): descend
1753         @:
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 $(KBUILD_EXTMOD)/.thinlto-cache
1761
1762 PHONY += prepare
1763 # now expand this into a simple variable to reduce the cost of shell evaluations
1764 prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT)
1765 prepare:
1766         @if [ "$(CC_VERSION_TEXT)" != $(CONFIG_CC_VERSION_TEXT) ]; then \
1767                 echo >&2 "warning: the compiler differs from the one used to build the kernel"; \
1768                 echo >&2 "  The kernel was built by: "$(CONFIG_CC_VERSION_TEXT); \
1769                 echo >&2 "  You are using:           $(CC_VERSION_TEXT)"; \
1770         fi
1771
1772 PHONY += help
1773 help:
1774         @echo  '  Building external modules.'
1775         @echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1776         @echo  ''
1777         @echo  '  modules         - default target, build the module(s)'
1778         @echo  '  modules_install - install the module'
1779         @echo  '  clean           - remove generated files in module directory only'
1780         @echo  ''
1781
1782 # no-op for external module builds
1783 PHONY += modules_prepare
1784
1785 endif # KBUILD_EXTMOD
1786
1787 # ---------------------------------------------------------------------------
1788 # Modules
1789
1790 PHONY += modules modules_install
1791
1792 ifdef CONFIG_MODULES
1793
1794 modules: modules_check
1795         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1796
1797 PHONY += modules_check
1798 modules_check: $(MODORDER)
1799         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1800
1801 quiet_cmd_depmod = DEPMOD  $(MODLIB)
1802       cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1803                    $(KERNELRELEASE)
1804
1805 modules_install:
1806         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1807         $(call cmd,depmod)
1808
1809 else # CONFIG_MODULES
1810
1811 # Modules not configured
1812 # ---------------------------------------------------------------------------
1813
1814 modules modules_install:
1815         @echo >&2 '***'
1816         @echo >&2 '*** The present kernel configuration has modules disabled.'
1817         @echo >&2 '*** To use the module feature, please run "make menuconfig" etc.'
1818         @echo >&2 '*** to enable CONFIG_MODULES.'
1819         @echo >&2 '***'
1820         @exit 1
1821
1822 endif # CONFIG_MODULES
1823
1824 # Single targets
1825 # ---------------------------------------------------------------------------
1826 # To build individual files in subdirectories, you can do like this:
1827 #
1828 #   make foo/bar/baz.s
1829 #
1830 # The supported suffixes for single-target are listed in 'single-targets'
1831 #
1832 # To build only under specific subdirectories, you can do like this:
1833 #
1834 #   make foo/bar/baz/
1835
1836 ifdef single-build
1837
1838 # .ko is special because modpost is needed
1839 single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1840 single-no-ko := $(sort $(patsubst %.ko,%.mod, $(MAKECMDGOALS)))
1841
1842 $(single-ko): single_modpost
1843         @:
1844 $(single-no-ko): descend
1845         @:
1846
1847 ifeq ($(KBUILD_EXTMOD),)
1848 # For the single build of in-tree modules, use a temporary file to avoid
1849 # the situation of modules_install installing an invalid modules.order.
1850 MODORDER := .modules.tmp
1851 endif
1852
1853 PHONY += single_modpost
1854 single_modpost: $(single-no-ko) modules_prepare
1855         $(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$m;) } > $(MODORDER)
1856         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1857
1858 KBUILD_MODULES := 1
1859
1860 export KBUILD_SINGLE_TARGETS := $(addprefix $(extmod_prefix), $(single-no-ko))
1861
1862 # trim unrelated directories
1863 build-dirs := $(foreach d, $(build-dirs), \
1864                         $(if $(filter $(d)/%, $(KBUILD_SINGLE_TARGETS)), $(d)))
1865
1866 endif
1867
1868 ifndef CONFIG_MODULES
1869 KBUILD_MODULES :=
1870 endif
1871
1872 # Handle descending into subdirectories listed in $(build-dirs)
1873 # Preset locale variables to speed up the build process. Limit locale
1874 # tweaks to this spot to avoid wrong language settings when running
1875 # make menuconfig etc.
1876 # Error messages still appears in the original language
1877 PHONY += descend $(build-dirs)
1878 descend: $(build-dirs)
1879 $(build-dirs): prepare
1880         $(Q)$(MAKE) $(build)=$@ \
1881         single-build=$(if $(filter-out $@/, $(filter $@/%, $(KBUILD_SINGLE_TARGETS))),1) \
1882         need-builtin=1 need-modorder=1
1883
1884 clean-dirs := $(addprefix _clean_, $(clean-dirs))
1885 PHONY += $(clean-dirs) clean
1886 $(clean-dirs):
1887         $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1888
1889 clean: $(clean-dirs)
1890         $(call cmd,rmfiles)
1891         @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1892                 \( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1893                 -o -name '*.ko.*' \
1894                 -o -name '*.dtb' -o -name '*.dtbo' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1895                 -o -name '*.dwo' -o -name '*.lst' \
1896                 -o -name '*.su' -o -name '*.mod' \
1897                 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1898                 -o -name '*.lex.c' -o -name '*.tab.[ch]' \
1899                 -o -name '*.asn1.[ch]' \
1900                 -o -name '*.symtypes' -o -name 'modules.order' \
1901                 -o -name '.tmp_*.o.*' \
1902                 -o -name '*.c.[012]*.*' \
1903                 -o -name '*.ll' \
1904                 -o -name '*.gcno' \
1905                 -o -name '*.*.symversions' \) -type f -print | xargs rm -f
1906
1907 # Generate tags for editors
1908 # ---------------------------------------------------------------------------
1909 quiet_cmd_tags = GEN     $@
1910       cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1911
1912 tags TAGS cscope gtags: FORCE
1913         $(call cmd,tags)
1914
1915 # Script to generate missing namespace dependencies
1916 # ---------------------------------------------------------------------------
1917
1918 PHONY += nsdeps
1919 nsdeps: export KBUILD_NSDEPS=1
1920 nsdeps: modules
1921         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1922
1923 # Clang Tooling
1924 # ---------------------------------------------------------------------------
1925
1926 quiet_cmd_gen_compile_commands = GEN     $@
1927       cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
1928
1929 $(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
1930         $(if $(KBUILD_EXTMOD),,$(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)) \
1931         $(if $(CONFIG_MODULES), $(MODORDER)) FORCE
1932         $(call if_changed,gen_compile_commands)
1933
1934 targets += $(extmod_prefix)compile_commands.json
1935
1936 PHONY += clang-tidy clang-analyzer
1937
1938 ifdef CONFIG_CC_IS_CLANG
1939 quiet_cmd_clang_tools = CHECK   $<
1940       cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
1941
1942 clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
1943         $(call cmd,clang_tools)
1944 else
1945 clang-tidy clang-analyzer:
1946         @echo "$@ requires CC=clang" >&2
1947         @false
1948 endif
1949
1950 # Scripts to check various things for consistency
1951 # ---------------------------------------------------------------------------
1952
1953 PHONY += includecheck versioncheck coccicheck export_report
1954
1955 includecheck:
1956         find $(srctree)/* $(RCS_FIND_IGNORE) \
1957                 -name '*.[hcS]' -type f -print | sort \
1958                 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1959
1960 versioncheck:
1961         find $(srctree)/* $(RCS_FIND_IGNORE) \
1962                 -name '*.[hcS]' -type f -print | sort \
1963                 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1964
1965 coccicheck:
1966         $(Q)$(BASH) $(srctree)/scripts/$@
1967
1968 export_report:
1969         $(PERL) $(srctree)/scripts/export_report.pl
1970
1971 PHONY += checkstack kernelrelease kernelversion image_name
1972
1973 # UML needs a little special treatment here.  It wants to use the host
1974 # toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
1975 # else wants $(ARCH), including people doing cross-builds, which means
1976 # that $(SUBARCH) doesn't work here.
1977 ifeq ($(ARCH), um)
1978 CHECKSTACK_ARCH := $(SUBARCH)
1979 else
1980 CHECKSTACK_ARCH := $(ARCH)
1981 endif
1982 checkstack:
1983         $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1984         $(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1985
1986 kernelrelease:
1987         @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1988
1989 kernelversion:
1990         @echo $(KERNELVERSION)
1991
1992 image_name:
1993         @echo $(KBUILD_IMAGE)
1994
1995 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
1996       cmd_rmfiles = rm -rf $(rm-files)
1997
1998 # read saved command lines for existing targets
1999 existing-targets := $(wildcard $(sort $(targets)))
2000
2001 -include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
2002
2003 endif # config-build
2004 endif # mixed-build
2005 endif # need-sub-make
2006
2007 PHONY += FORCE
2008 FORCE:
2009
2010 # Declare the contents of the PHONY variable as phony.  We keep that
2011 # information in a variable so we can use it in if_changed and friends.
2012 .PHONY: $(PHONY)