Makefile

   1 # SPDX-License-Identifier: GPL-2.0
   2 VERSION = 4
   3 PATCHLEVEL = 14
   4 SUBLEVEL = 87
   5 EXTRAVERSION =
   6 NAME = Petit Gorille
   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 # That's our default target when none is given on the command line
  15 PHONY := _all
  16 _all:
  17
  18 # o Do not use make's built-in rules and variables
  19 #   (this increases performance and avoids hard-to-debug behaviour);
  20 # o Look for make include files relative to root of kernel src
  21 MAKEFLAGS += -rR --include-dir=$(CURDIR)
  22
  23 # Avoid funny character set dependencies
  24 unexport LC_ALL
  25 LC_COLLATE=C
  26 LC_NUMERIC=C
  27 export LC_COLLATE LC_NUMERIC
  28
  29 # Avoid interference with shell env settings
  30 unexport GREP_OPTIONS
  31
  32 # We are using a recursive build, so we need to do a little thinking
  33 # to get the ordering right.
  34 #
  35 # Most importantly: sub-Makefiles should only ever modify files in
  36 # their own directory. If in some directory we have a dependency on
  37 # a file in another dir (which doesn't happen often, but it's often
  38 # unavoidable when linking the built-in.o targets which finally
  39 # turn into vmlinux), we will call a sub make in that other dir, and
  40 # after that we are sure that everything which is in that other dir
  41 # is now up to date.
  42 #
  43 # The only cases where we need to modify files which have global
  44 # effects are thus separated out and done before the recursive
  45 # descending is started. They are now explicitly listed as the
  46 # prepare rule.
  47
  48 # Beautify output
  49 # ---------------------------------------------------------------------------
  50 #
  51 # Normally, we echo the whole command before executing it. By making
  52 # that echo $($(quiet)$(cmd)), we now have the possibility to set
  53 # $(quiet) to choose other forms of output instead, e.g.
  54 #
  55 #         quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
  56 #         cmd_cc_o_c       = $(CC) $(c_flags) -c -o $@ $<
  57 #
  58 # If $(quiet) is empty, the whole command will be printed.
  59 # If it is set to "quiet_", only the short version will be printed.
  60 # If it is set to "silent_", nothing will be printed at all, since
  61 # the variable $(silent_cmd_cc_o_c) doesn't exist.
  62 #
  63 # A simple variant is to prefix commands with $(Q) - that's useful
  64 # for commands that shall be hidden in non-verbose mode.
  65 #
  66 #       $(Q)ln $@ :<
  67 #
  68 # If KBUILD_VERBOSE equals 0 then the above command will be hidden.
  69 # If KBUILD_VERBOSE equals 1 then the above command is displayed.
  70 #
  71 # To put more focus on warnings, be less verbose as default
  72 # Use 'make V=1' to see the full commands
  73
  74 ifeq ("$(origin V)", "command line")
  75   KBUILD_VERBOSE = $(V)
  76 endif
  77 ifndef KBUILD_VERBOSE
  78   KBUILD_VERBOSE = 0
  79 endif
  80
  81 ifeq ($(KBUILD_VERBOSE),1)
  82   quiet =
  83   Q =
  84 else
  85   quiet=quiet_
  86   Q = @
  87 endif
  88
  89 # If the user is running make -s (silent mode), suppress echoing of
  90 # commands
  91
  92 ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
  93   quiet=silent_
  94   tools_silent=s
  95 endif
  96
  97 export quiet Q KBUILD_VERBOSE
  98
  99 # kbuild supports saving output files in a separate directory.
 100 # To locate output files in a separate directory two syntaxes are supported.
 101 # In both cases the working directory must be the root of the kernel src.
 102 # 1) O=
 103 # Use "make O=dir/to/store/output/files/"
 104 #
 105 # 2) Set KBUILD_OUTPUT
 106 # Set the environment variable KBUILD_OUTPUT to point to the directory
 107 # where the output files shall be placed.
 108 # export KBUILD_OUTPUT=dir/to/store/output/files/
 109 # make
 110 #
 111 # The O= assignment takes precedence over the KBUILD_OUTPUT environment
 112 # variable.
 113
 114 # KBUILD_SRC is not intended to be used by the regular user (for now),
 115 # it is set on invocation of make with KBUILD_OUTPUT or O= specified.
 116 ifeq ($(KBUILD_SRC),)
 117
 118 # OK, Make called in directory where kernel src resides
 119 # Do we want to locate output files in a separate directory?
 120 ifeq ("$(origin O)", "command line")
 121   KBUILD_OUTPUT := $(O)
 122 endif
 123
 124 # Cancel implicit rules on top Makefile
 125 $(CURDIR)/Makefile Makefile: ;
 126
 127 ifneq ($(words $(subst :, ,$(CURDIR))), 1)
 128   $(error main directory cannot contain spaces nor colons)
 129 endif
 130
 131 ifneq ($(KBUILD_OUTPUT),)
 132 # check that the output directory actually exists
 133 saved-output := $(KBUILD_OUTPUT)
 134 KBUILD_OUTPUT := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) \
 135                                                                 && /bin/pwd)
 136 $(if $(KBUILD_OUTPUT),, \
 137      $(error failed to create output directory "$(saved-output)"))
 138
 139 PHONY += $(MAKECMDGOALS) sub-make
 140
 141 $(filter-out _all sub-make $(CURDIR)/Makefile, $(MAKECMDGOALS)) _all: sub-make
 142         @:
 143
 144 # Invoke a second make in the output directory, passing relevant variables
 145 sub-make:
 146         $(Q)$(MAKE) -C $(KBUILD_OUTPUT) KBUILD_SRC=$(CURDIR) \
 147         -f $(CURDIR)/Makefile $(filter-out _all sub-make,$(MAKECMDGOALS))
 148
 149 # Leave processing to above invocation of make
 150 skip-makefile := 1
 151 endif # ifneq ($(KBUILD_OUTPUT),)
 152 endif # ifeq ($(KBUILD_SRC),)
 153
 154 # We process the rest of the Makefile if this is the final invocation of make
 155 ifeq ($(skip-makefile),)
 156
 157 # Do not print "Entering directory ...",
 158 # but we want to display it when entering to the output directory
 159 # so that IDEs/editors are able to understand relative filenames.
 160 MAKEFLAGS += --no-print-directory
 161
 162 # Call a source code checker (by default, "sparse") as part of the
 163 # C compilation.
 164 #
 165 # Use 'make C=1' to enable checking of only re-compiled files.
 166 # Use 'make C=2' to enable checking of *all* source files, regardless
 167 # of whether they are re-compiled or not.
 168 #
 169 # See the file "Documentation/dev-tools/sparse.rst" for more details,
 170 # including where to get the "sparse" utility.
 171
 172 ifeq ("$(origin C)", "command line")
 173   KBUILD_CHECKSRC = $(C)
 174 endif
 175 ifndef KBUILD_CHECKSRC
 176   KBUILD_CHECKSRC = 0
 177 endif
 178
 179 # Use make M=dir to specify directory of external module to build
 180 # Old syntax make ... SUBDIRS=$PWD is still supported
 181 # Setting the environment variable KBUILD_EXTMOD take precedence
 182 ifdef SUBDIRS
 183   KBUILD_EXTMOD ?= $(SUBDIRS)
 184 endif
 185
 186 ifeq ("$(origin M)", "command line")
 187   KBUILD_EXTMOD := $(M)
 188 endif
 189
 190 ifeq ($(KBUILD_SRC),)
 191         # building in the source tree
 192         srctree := .
 193 else
 194         ifeq ($(KBUILD_SRC)/,$(dir $(CURDIR)))
 195                 # building in a subdirectory of the source tree
 196                 srctree := ..
 197         else
 198                 srctree := $(KBUILD_SRC)
 199         endif
 200 endif
 201
 202 export KBUILD_CHECKSRC KBUILD_EXTMOD KBUILD_SRC
 203
 204 objtree         := .
 205 src             := $(srctree)
 206 obj             := $(objtree)
 207
 208 VPATH           := $(srctree)$(if $(KBUILD_EXTMOD),:$(KBUILD_EXTMOD))
 209
 210 export srctree objtree VPATH
 211
 212 # To make sure we do not include .config for any of the *config targets
 213 # catch them early, and hand them over to scripts/kconfig/Makefile
 214 # It is allowed to specify more targets when calling make, including
 215 # mixing *config targets and build targets.
 216 # For example 'make oldconfig all'.
 217 # Detect when mixed targets is specified, and make a second invocation
 218 # of make so .config is not included in this case either (for *config).
 219
 220 version_h := include/generated/uapi/linux/version.h
 221 old_version_h := include/linux/version.h
 222
 223 no-dot-config-targets := clean mrproper distclean \
 224                          cscope gtags TAGS tags help% %docs check% coccicheck \
 225                          $(version_h) headers_% archheaders archscripts \
 226                          kernelversion %src-pkg
 227
 228 config-targets := 0
 229 mixed-targets  := 0
 230 dot-config     := 1
 231
 232 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
 233         ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
 234                 dot-config := 0
 235         endif
 236 endif
 237
 238 ifeq ($(KBUILD_EXTMOD),)
 239         ifneq ($(filter config %config,$(MAKECMDGOALS)),)
 240                 config-targets := 1
 241                 ifneq ($(words $(MAKECMDGOALS)),1)
 242                         mixed-targets := 1
 243                 endif
 244         endif
 245 endif
 246 # install and modules_install need also be processed one by one
 247 ifneq ($(filter install,$(MAKECMDGOALS)),)
 248         ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
 249                 mixed-targets := 1
 250         endif
 251 endif
 252
 253 ifeq ($(mixed-targets),1)
 254 # ===========================================================================
 255 # We're called with mixed targets (*config and build targets).
 256 # Handle them one by one.
 257
 258 PHONY += $(MAKECMDGOALS) __build_one_by_one
 259
 260 $(filter-out __build_one_by_one, $(MAKECMDGOALS)): __build_one_by_one
 261         @:
 262
 263 __build_one_by_one:
 264         $(Q)set -e; \
 265         for i in $(MAKECMDGOALS); do \
 266                 $(MAKE) -f $(srctree)/Makefile $$i; \
 267         done
 268
 269 else
 270
 271 # We need some generic definitions (do not try to remake the file).
 272 scripts/Kbuild.include: ;
 273 include scripts/Kbuild.include
 274
 275 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
 276 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
 277 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
 278 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
 279
 280 # SUBARCH tells the usermode build what the underlying arch is.  That is set
 281 # first, and if a usermode build is happening, the "ARCH=um" on the command
 282 # line overrides the setting of ARCH below.  If a native build is happening,
 283 # then ARCH is assigned, getting whatever value it gets normally, and
 284 # SUBARCH is subsequently ignored.
 285
 286 SUBARCH := $(shell uname -m | sed -e s/i.86/x86/ -e s/x86_64/x86/ \
 287                                   -e s/sun4u/sparc64/ \
 288                                   -e s/arm.*/arm/ -e s/sa110/arm/ \
 289                                   -e s/s390x/s390/ -e s/parisc64/parisc/ \
 290                                   -e s/ppc.*/powerpc/ -e s/mips.*/mips/ \
 291                                   -e s/sh[234].*/sh/ -e s/aarch64.*/arm64/ )
 292
 293 # Cross compiling and selecting different set of gcc/bin-utils
 294 # ---------------------------------------------------------------------------
 295 #
 296 # When performing cross compilation for other architectures ARCH shall be set
 297 # to the target architecture. (See arch/* for the possibilities).
 298 # ARCH can be set during invocation of make:
 299 # make ARCH=ia64
 300 # Another way is to have ARCH set in the environment.
 301 # The default ARCH is the host where make is executed.
 302
 303 # CROSS_COMPILE specify the prefix used for all executables used
 304 # during compilation. Only gcc and related bin-utils executables
 305 # are prefixed with $(CROSS_COMPILE).
 306 # CROSS_COMPILE can be set on the command line
 307 # make CROSS_COMPILE=ia64-linux-
 308 # Alternatively CROSS_COMPILE can be set in the environment.
 309 # A third alternative is to store a setting in .config so that plain
 310 # "make" in the configured kernel build directory always uses that.
 311 # Default value for CROSS_COMPILE is not to prefix executables
 312 # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
 313 ARCH            ?= $(SUBARCH)
 314 CROSS_COMPILE   ?= $(CONFIG_CROSS_COMPILE:"%"=%)
 315
 316 # Architecture as present in compile.h
 317 UTS_MACHINE     := $(ARCH)
 318 SRCARCH         := $(ARCH)
 319
 320 # Additional ARCH settings for x86
 321 ifeq ($(ARCH),i386)
 322         SRCARCH := x86
 323 endif
 324 ifeq ($(ARCH),x86_64)
 325         SRCARCH := x86
 326 endif
 327
 328 # Additional ARCH settings for sparc
 329 ifeq ($(ARCH),sparc32)
 330        SRCARCH := sparc
 331 endif
 332 ifeq ($(ARCH),sparc64)
 333        SRCARCH := sparc
 334 endif
 335
 336 # Additional ARCH settings for sh
 337 ifeq ($(ARCH),sh64)
 338        SRCARCH := sh
 339 endif
 340
 341 # Additional ARCH settings for tile
 342 ifeq ($(ARCH),tilepro)
 343        SRCARCH := tile
 344 endif
 345 ifeq ($(ARCH),tilegx)
 346        SRCARCH := tile
 347 endif
 348
 349 # Where to locate arch specific headers
 350 hdr-arch  := $(SRCARCH)
 351
 352 KCONFIG_CONFIG  ?= .config
 353 export KCONFIG_CONFIG
 354
 355 # SHELL used by kbuild
 356 CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
 357           else if [ -x /bin/bash ]; then echo /bin/bash; \
 358           else echo sh; fi ; fi)
 359
 360 HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
 361 HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
 362 HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
 363
 364 HOSTCC       = gcc
 365 HOSTCXX      = g++
 366 HOSTCFLAGS   := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 \
 367                 -fomit-frame-pointer -std=gnu89 $(HOST_LFS_CFLAGS)
 368 HOSTCXXFLAGS := -O2 $(HOST_LFS_CFLAGS)
 369 HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS)
 370 HOST_LOADLIBES := $(HOST_LFS_LIBS)
 371
 372 # Make variables (CC, etc...)
 373 AS              = $(CROSS_COMPILE)as
 374 LD              = $(CROSS_COMPILE)ld
 375 LDGOLD          = $(CROSS_COMPILE)ld.gold
 376 CC              = $(CROSS_COMPILE)gcc
 377 CPP             = $(CC) -E
 378 AR              = $(CROSS_COMPILE)ar
 379 NM              = $(CROSS_COMPILE)nm
 380 STRIP           = $(CROSS_COMPILE)strip
 381 OBJCOPY         = $(CROSS_COMPILE)objcopy
 382 OBJDUMP         = $(CROSS_COMPILE)objdump
 383 AWK             = awk
 384 GENKSYMS        = scripts/genksyms/genksyms
 385 INSTALLKERNEL  := installkernel
 386 DEPMOD          = /sbin/depmod
 387 PERL            = perl
 388 PYTHON          = python
 389 CHECK           = sparse
 390
 391 CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
 392                   -Wbitwise -Wno-return-void $(CF)
 393 NOSTDINC_FLAGS  =
 394 CFLAGS_MODULE   =
 395 AFLAGS_MODULE   =
 396 LDFLAGS_MODULE  =
 397 CFLAGS_KERNEL   =
 398 AFLAGS_KERNEL   =
 399 LDFLAGS_vmlinux =
 400
 401 # Use USERINCLUDE when you must reference the UAPI directories only.
 402 USERINCLUDE    := \
 403                 -I$(srctree)/arch/$(hdr-arch)/include/uapi \
 404                 -I$(objtree)/arch/$(hdr-arch)/include/generated/uapi \
 405                 -I$(srctree)/include/uapi \
 406                 -I$(objtree)/include/generated/uapi \
 407                 -include $(srctree)/include/linux/kconfig.h
 408
 409 # Use LINUXINCLUDE when you must reference the include/ directory.
 410 # Needed to be compatible with the O= option
 411 LINUXINCLUDE    := \
 412                 -I$(srctree)/arch/$(hdr-arch)/include \
 413                 -I$(objtree)/arch/$(hdr-arch)/include/generated \
 414                 $(if $(KBUILD_SRC), -I$(srctree)/include) \
 415                 -I$(objtree)/include \
 416                 $(USERINCLUDE)
 417
 418 KBUILD_AFLAGS   := -D__ASSEMBLY__
 419 KBUILD_CFLAGS   := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
 420                    -fno-strict-aliasing -fno-common -fshort-wchar \
 421                    -Werror-implicit-function-declaration \
 422                    -Wno-format-security \
 423                    -std=gnu89
 424 KBUILD_CPPFLAGS := -D__KERNEL__
 425 KBUILD_AFLAGS_KERNEL :=
 426 KBUILD_CFLAGS_KERNEL :=
 427 KBUILD_AFLAGS_MODULE  := -DMODULE
 428 KBUILD_CFLAGS_MODULE  := -DMODULE
 429 KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
 430 GCC_PLUGINS_CFLAGS :=
 431
 432 export ARCH SRCARCH CONFIG_SHELL HOSTCC HOSTCFLAGS CROSS_COMPILE AS LD CC
 433 export CPP AR NM STRIP OBJCOPY OBJDUMP HOSTLDFLAGS HOST_LOADLIBES
 434 export MAKE AWK GENKSYMS INSTALLKERNEL PERL PYTHON UTS_MACHINE
 435 export HOSTCXX HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
 436
 437 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS LDFLAGS
 438 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
 439 export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN
 440 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
 441 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
 442 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
 443 export KBUILD_ARFLAGS
 444
 445 # When compiling out-of-tree modules, put MODVERDIR in the module
 446 # tree rather than in the kernel tree. The kernel tree might
 447 # even be read-only.
 448 export MODVERDIR := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_versions
 449
 450 # Files to ignore in find ... statements
 451
 452 export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
 453                           -name CVS -o -name .pc -o -name .hg -o -name .git \) \
 454                           -prune -o
 455 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
 456                          --exclude CVS --exclude .pc --exclude .hg --exclude .git
 457
 458 # ===========================================================================
 459 # Rules shared between *config targets and build targets
 460
 461 # Basic helpers built in scripts/basic/
 462 PHONY += scripts_basic
 463 scripts_basic:
 464         $(Q)$(MAKE) $(build)=scripts/basic
 465         $(Q)rm -f .tmp_quiet_recordmcount
 466
 467 # To avoid any implicit rule to kick in, define an empty command.
 468 scripts/basic/%: scripts_basic ;
 469
 470 PHONY += outputmakefile
 471 # outputmakefile generates a Makefile in the output directory, if using a
 472 # separate output directory. This allows convenient use of make in the
 473 # output directory.
 474 outputmakefile:
 475 ifneq ($(KBUILD_SRC),)
 476         $(Q)ln -fsn $(srctree) source
 477         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile \
 478             $(srctree) $(objtree) $(VERSION) $(PATCHLEVEL)
 479 endif
 480
 481 ifeq ($(cc-name),clang)
 482 ifneq ($(CROSS_COMPILE),)
 483 CLANG_TRIPLE    ?= $(CROSS_COMPILE)
 484 CLANG_TARGET    := --target=$(notdir $(CLANG_TRIPLE:%-=%))
 485 GCC_TOOLCHAIN   := $(realpath $(dir $(shell which $(LD)))/..)
 486 endif
 487 ifneq ($(GCC_TOOLCHAIN),)
 488 CLANG_GCC_TC    := --gcc-toolchain=$(GCC_TOOLCHAIN)
 489 endif
 490 KBUILD_CFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC) $(CLANG_PREFIX)
 491 KBUILD_AFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC) $(CLANG_PREFIX)
 492 KBUILD_CFLAGS += $(call cc-option, -no-integrated-as)
 493 KBUILD_AFLAGS += $(call cc-option, -no-integrated-as)
 494 endif
 495
 496 RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
 497 RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
 498 RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
 499 RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
 500 RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
 501 RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
 502 export RETPOLINE_CFLAGS
 503 export RETPOLINE_VDSO_CFLAGS
 504
 505 ifeq ($(config-targets),1)
 506 # ===========================================================================
 507 # *config targets only - make sure prerequisites are updated, and descend
 508 # in scripts/kconfig to make the *config target
 509
 510 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
 511 # KBUILD_DEFCONFIG may point out an alternative default configuration
 512 # used for 'make defconfig'
 513 include arch/$(SRCARCH)/Makefile
 514 export KBUILD_DEFCONFIG KBUILD_KCONFIG
 515
 516 config: scripts_basic outputmakefile FORCE
 517         $(Q)$(MAKE) $(build)=scripts/kconfig $@
 518
 519 %config: scripts_basic outputmakefile FORCE
 520         $(Q)$(MAKE) $(build)=scripts/kconfig $@
 521
 522 else
 523 # ===========================================================================
 524 # Build targets only - this includes vmlinux, arch specific targets, clean
 525 # targets and others. In general all targets except *config targets.
 526
 527 # If building an external module we do not care about the all: rule
 528 # but instead _all depend on modules
 529 PHONY += all
 530 ifeq ($(KBUILD_EXTMOD),)
 531 _all: all
 532 else
 533 _all: modules
 534 endif
 535
 536 # Decide whether to build built-in, modular, or both.
 537 # Normally, just do built-in.
 538
 539 KBUILD_MODULES :=
 540 KBUILD_BUILTIN := 1
 541
 542 # If we have only "make modules", don't compile built-in objects.
 543 # When we're building modules with modversions, we need to consider
 544 # the built-in objects during the descend as well, in order to
 545 # make sure the checksums are up to date before we record them.
 546
 547 ifeq ($(MAKECMDGOALS),modules)
 548   KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
 549 endif
 550
 551 # If we have "make <whatever> modules", compile modules
 552 # in addition to whatever we do anyway.
 553 # Just "make" or "make all" shall build modules as well
 554
 555 ifneq ($(filter all _all modules,$(MAKECMDGOALS)),)
 556   KBUILD_MODULES := 1
 557 endif
 558
 559 ifeq ($(MAKECMDGOALS),)
 560   KBUILD_MODULES := 1
 561 endif
 562
 563 export KBUILD_MODULES KBUILD_BUILTIN
 564
 565 ifeq ($(KBUILD_EXTMOD),)
 566 # Additional helpers built in scripts/
 567 # Carefully list dependencies so we do not try to build scripts twice
 568 # in parallel
 569 PHONY += scripts
 570 scripts: scripts_basic include/config/auto.conf include/config/tristate.conf \
 571          asm-generic gcc-plugins
 572         $(Q)$(MAKE) $(build)=$(@)
 573
 574 # Objects we will link into vmlinux / subdirs we need to visit
 575 init-y          := init/
 576 drivers-y       := drivers/ sound/ firmware/
 577 net-y           := net/
 578 libs-y          := lib/
 579 core-y          := usr/
 580 virt-y          := virt/
 581 endif # KBUILD_EXTMOD
 582
 583 ifeq ($(dot-config),1)
 584 # Read in config
 585 -include include/config/auto.conf
 586
 587 ifeq ($(KBUILD_EXTMOD),)
 588 # Read in dependencies to all Kconfig* files, make sure to run
 589 # oldconfig if changes are detected.
 590 -include include/config/auto.conf.cmd
 591
 592 # To avoid any implicit rule to kick in, define an empty command
 593 $(KCONFIG_CONFIG) include/config/auto.conf.cmd: ;
 594
 595 # If .config is newer than include/config/auto.conf, someone tinkered
 596 # with it and forgot to run make oldconfig.
 597 # if auto.conf.cmd is missing then we are probably in a cleaned tree so
 598 # we execute the config step to be sure to catch updated Kconfig files
 599 include/config/%.conf: $(KCONFIG_CONFIG) include/config/auto.conf.cmd
 600         $(Q)$(MAKE) -f $(srctree)/Makefile silentoldconfig
 601 else
 602 # external modules needs include/generated/autoconf.h and include/config/auto.conf
 603 # but do not care if they are up-to-date. Use auto.conf to trigger the test
 604 PHONY += include/config/auto.conf
 605
 606 include/config/auto.conf:
 607         $(Q)test -e include/generated/autoconf.h -a -e $@ || (          \
 608         echo >&2;                                                       \
 609         echo >&2 "  ERROR: Kernel configuration is invalid.";           \
 610         echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
 611         echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";      \
 612         echo >&2 ;                                                      \
 613         /bin/false)
 614
 615 endif # KBUILD_EXTMOD
 616
 617 else
 618 # Dummy target needed, because used as prerequisite
 619 include/config/auto.conf: ;
 620 endif # $(dot-config)
 621
 622 # For the kernel to actually contain only the needed exported symbols,
 623 # we have to build modules as well to determine what those symbols are.
 624 # (this can be evaluated only once include/config/auto.conf has been included)
 625 ifdef CONFIG_TRIM_UNUSED_KSYMS
 626   KBUILD_MODULES := 1
 627 endif
 628
 629 # The all: target is the default when no target is given on the
 630 # command line.
 631 # This allow a user to issue only 'make' to build a kernel including modules
 632 # Defaults to vmlinux, but the arch makefile usually adds further targets
 633 all: vmlinux
 634
 635 KBUILD_CFLAGS   += $(call cc-option,-fno-PIE)
 636 KBUILD_AFLAGS   += $(call cc-option,-fno-PIE)
 637 CFLAGS_GCOV     := -fprofile-arcs -ftest-coverage -fno-tree-loop-im $(call cc-disable-warning,maybe-uninitialized,)
 638 CFLAGS_KCOV     := $(call cc-option,-fsanitize-coverage=trace-pc,)
 639 export CFLAGS_GCOV CFLAGS_KCOV
 640
 641 # Make toolchain changes before including arch/$(SRCARCH)/Makefile to ensure
 642 # ar/cc/ld-* macros return correct values.
 643 ifdef CONFIG_LTO_CLANG
 644 # use GNU gold with LLVMgold for LTO linking, and LD for vmlinux_link
 645 LDFINAL_vmlinux := $(LD)
 646 LD              := $(LDGOLD)
 647 LDFLAGS         += -plugin LLVMgold.so
 648 # use llvm-ar for building symbol tables from IR files, and llvm-dis instead
 649 # of objdump for processing symbol versions and exports
 650 LLVM_AR         := llvm-ar
 651 LLVM_DIS        := llvm-dis
 652 export LLVM_AR LLVM_DIS
 653 endif
 654
 655 # The arch Makefile can set ARCH_{CPP,A,C}FLAGS to override the default
 656 # values of the respective KBUILD_* variables
 657 ARCH_CPPFLAGS :=
 658 ARCH_AFLAGS :=
 659 ARCH_CFLAGS :=
 660 include arch/$(SRCARCH)/Makefile
 661
 662 KBUILD_CFLAGS   += $(call cc-option,-fno-delete-null-pointer-checks,)
 663 KBUILD_CFLAGS   += $(call cc-disable-warning,frame-address,)
 664 KBUILD_CFLAGS   += $(call cc-disable-warning, format-truncation)
 665 KBUILD_CFLAGS   += $(call cc-disable-warning, format-overflow)
 666 KBUILD_CFLAGS   += $(call cc-disable-warning, int-in-bool-context)
 667 KBUILD_CFLAGS   += $(call cc-disable-warning, attribute-alias)
 668
 669 ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
 670 KBUILD_CFLAGS   += $(call cc-option,-Oz,-Os)
 671 KBUILD_CFLAGS   += $(call cc-disable-warning,maybe-uninitialized,)
 672 else
 673 ifdef CONFIG_PROFILE_ALL_BRANCHES
 674 KBUILD_CFLAGS   += -O2 $(call cc-disable-warning,maybe-uninitialized,)
 675 else
 676 KBUILD_CFLAGS   += -O2
 677 endif
 678 endif
 679
 680 KBUILD_CFLAGS += $(call cc-ifversion, -lt, 0409, \
 681                         $(call cc-disable-warning,maybe-uninitialized,))
 682
 683 # Tell gcc to never replace conditional load with a non-conditional one
 684 KBUILD_CFLAGS   += $(call cc-option,--param=allow-store-data-races=0)
 685
 686 # check for 'asm goto'
 687 ifeq ($(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC) $(KBUILD_CFLAGS)), y)
 688         KBUILD_CFLAGS += -DCC_HAVE_ASM_GOTO
 689         KBUILD_AFLAGS += -DCC_HAVE_ASM_GOTO
 690 endif
 691
 692 include scripts/Makefile.gcc-plugins
 693
 694 ifdef CONFIG_READABLE_ASM
 695 # Disable optimizations that make assembler listings hard to read.
 696 # reorder blocks reorders the control in the function
 697 # ipa clone creates specialized cloned functions
 698 # partial inlining inlines only parts of functions
 699 KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
 700                  $(call cc-option,-fno-ipa-cp-clone,) \
 701                  $(call cc-option,-fno-partial-inlining)
 702 endif
 703
 704 ifneq ($(CONFIG_FRAME_WARN),0)
 705 KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
 706 endif
 707
 708 # This selects the stack protector compiler flag. Testing it is delayed
 709 # until after .config has been reprocessed, in the prepare-compiler-check
 710 # target.
 711 ifdef CONFIG_CC_STACKPROTECTOR_REGULAR
 712   stackp-flag := -fstack-protector
 713   stackp-name := REGULAR
 714 else
 715 ifdef CONFIG_CC_STACKPROTECTOR_STRONG
 716   stackp-flag := -fstack-protector-strong
 717   stackp-name := STRONG
 718 else
 719   # Force off for distro compilers that enable stack protector by default.
 720   stackp-flag := $(call cc-option, -fno-stack-protector)
 721 endif
 722 endif
 723 # Find arch-specific stack protector compiler sanity-checking script.
 724 ifdef CONFIG_CC_STACKPROTECTOR
 725   stackp-path := $(srctree)/scripts/gcc-$(SRCARCH)_$(BITS)-has-stack-protector.sh
 726   stackp-check := $(wildcard $(stackp-path))
 727 endif
 728 KBUILD_CFLAGS += $(stackp-flag)
 729
 730 ifeq ($(cc-name),clang)
 731 KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
 732 KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier)
 733 KBUILD_CFLAGS += $(call cc-disable-warning, gnu)
 734 KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
 735 KBUILD_CFLAGS += $(call cc-disable-warning, duplicate-decl-specifier)
 736 # Quiet clang warning: comparison of unsigned expression < 0 is always false
 737 KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare)
 738 # CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
 739 # source of a reference will be _MergedGlobals and not on of the whitelisted names.
 740 # See modpost pattern 2
 741 KBUILD_CFLAGS += $(call cc-option, -mno-global-merge,)
 742 KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior)
 743 else
 744
 745 # These warnings generated too much noise in a regular build.
 746 # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
 747 KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
 748 endif
 749
 750 KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
 751 ifdef CONFIG_FRAME_POINTER
 752 KBUILD_CFLAGS   += -fno-omit-frame-pointer -fno-optimize-sibling-calls
 753 else
 754 # Some targets (ARM with Thumb2, for example), can't be built with frame
 755 # pointers.  For those, we don't have FUNCTION_TRACER automatically
 756 # select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
 757 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
 758 # -fomit-frame-pointer with FUNCTION_TRACER.
 759 ifndef CONFIG_FUNCTION_TRACER
 760 KBUILD_CFLAGS   += -fomit-frame-pointer
 761 endif
 762 endif
 763
 764 KBUILD_CFLAGS   += $(call cc-option, -fno-var-tracking-assignments)
 765
 766 ifdef CONFIG_DEBUG_INFO
 767 ifdef CONFIG_DEBUG_INFO_SPLIT
 768 KBUILD_CFLAGS   += $(call cc-option, -gsplit-dwarf, -g)
 769 else
 770 KBUILD_CFLAGS   += -g
 771 endif
 772 KBUILD_AFLAGS   += -Wa,-gdwarf-2
 773 endif
 774 ifdef CONFIG_DEBUG_INFO_DWARF4
 775 KBUILD_CFLAGS   += $(call cc-option, -gdwarf-4,)
 776 endif
 777
 778 ifdef CONFIG_DEBUG_INFO_REDUCED
 779 KBUILD_CFLAGS   += $(call cc-option, -femit-struct-debug-baseonly) \
 780                    $(call cc-option,-fno-var-tracking)
 781 endif
 782
 783 ifdef CONFIG_FUNCTION_TRACER
 784 ifndef CC_FLAGS_FTRACE
 785 CC_FLAGS_FTRACE := -pg
 786 endif
 787 export CC_FLAGS_FTRACE
 788 ifdef CONFIG_HAVE_FENTRY
 789 CC_USING_FENTRY := $(call cc-option, -mfentry -DCC_USING_FENTRY)
 790 endif
 791 KBUILD_CFLAGS   += $(CC_FLAGS_FTRACE) $(CC_USING_FENTRY)
 792 KBUILD_AFLAGS   += $(CC_USING_FENTRY)
 793 ifdef CONFIG_DYNAMIC_FTRACE
 794         ifdef CONFIG_HAVE_C_RECORDMCOUNT
 795                 BUILD_C_RECORDMCOUNT := y
 796                 export BUILD_C_RECORDMCOUNT
 797         endif
 798 endif
 799 endif
 800
 801 # We trigger additional mismatches with less inlining
 802 ifdef CONFIG_DEBUG_SECTION_MISMATCH
 803 KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
 804 endif
 805
 806 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
 807 KBUILD_CFLAGS   += $(call cc-option,-ffunction-sections,)
 808 KBUILD_CFLAGS   += $(call cc-option,-fdata-sections,)
 809 endif
 810
 811 ifdef CONFIG_LTO_CLANG
 812 lto-clang-flags := -flto -fvisibility=hidden
 813
 814 # allow disabling only clang LTO where needed
 815 DISABLE_LTO_CLANG := -fno-lto -fvisibility=default
 816 export DISABLE_LTO_CLANG
 817 endif
 818
 819 ifdef CONFIG_LTO
 820 lto-flags       := $(lto-clang-flags)
 821 KBUILD_CFLAGS   += $(lto-flags)
 822
 823 DISABLE_LTO     := $(DISABLE_LTO_CLANG)
 824 export DISABLE_LTO
 825
 826 # LDFINAL_vmlinux and LDFLAGS_FINAL_vmlinux can be set to override
 827 # the linker and flags for vmlinux_link.
 828 export LDFINAL_vmlinux LDFLAGS_FINAL_vmlinux
 829 endif
 830
 831 ifdef CONFIG_CFI_CLANG
 832 cfi-clang-flags += -fsanitize=cfi
 833 DISABLE_CFI_CLANG := -fno-sanitize=cfi
 834 ifdef CONFIG_MODULES
 835 cfi-clang-flags += -fsanitize-cfi-cross-dso
 836 DISABLE_CFI_CLANG += -fno-sanitize-cfi-cross-dso
 837 endif
 838 ifdef CONFIG_CFI_PERMISSIVE
 839 cfi-clang-flags += -fsanitize-recover=cfi -fno-sanitize-trap=cfi
 840 endif
 841
 842 # also disable CFI when LTO is disabled
 843 DISABLE_LTO_CLANG += $(DISABLE_CFI_CLANG)
 844 # allow disabling only clang CFI where needed
 845 export DISABLE_CFI_CLANG
 846 endif
 847
 848 ifdef CONFIG_CFI
 849 # cfi-flags are re-tested in prepare-compiler-check
 850 cfi-flags       := $(cfi-clang-flags)
 851 KBUILD_CFLAGS   += $(cfi-flags)
 852
 853 DISABLE_CFI     := $(DISABLE_CFI_CLANG)
 854 DISABLE_LTO     += $(DISABLE_CFI)
 855 export DISABLE_CFI
 856 endif
 857
 858 # arch Makefile may override CC so keep this after arch Makefile is included
 859 NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
 860 CHECKFLAGS     += $(NOSTDINC_FLAGS)
 861
 862 # warn about C99 declaration after statement
 863 KBUILD_CFLAGS += $(call cc-option,-Wdeclaration-after-statement,)
 864
 865 # disable pointer signed / unsigned warnings in gcc 4.0
 866 KBUILD_CFLAGS += $(call cc-disable-warning, pointer-sign)
 867
 868 # disable stringop warnings in gcc 8+
 869 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
 870
 871 # disable invalid "can't wrap" optimizations for signed / pointers
 872 KBUILD_CFLAGS   += $(call cc-option,-fno-strict-overflow)
 873
 874 # clang sets -fmerge-all-constants by default as optimization, but this
 875 # is non-conforming behavior for C and in fact breaks the kernel, so we
 876 # need to disable it here generally.
 877 KBUILD_CFLAGS   += $(call cc-option,-fno-merge-all-constants)
 878
 879 # for gcc -fno-merge-all-constants disables everything, but it is fine
 880 # to have actual conforming behavior enabled.
 881 KBUILD_CFLAGS   += $(call cc-option,-fmerge-constants)
 882
 883 # Make sure -fstack-check isn't enabled (like gentoo apparently did)
 884 KBUILD_CFLAGS  += $(call cc-option,-fno-stack-check,)
 885
 886 # conserve stack if available
 887 KBUILD_CFLAGS   += $(call cc-option,-fconserve-stack)
 888
 889 # disallow errors like 'EXPORT_GPL(foo);' with missing header
 890 KBUILD_CFLAGS   += $(call cc-option,-Werror=implicit-int)
 891
 892 # require functions to have arguments in prototypes, not empty 'int foo()'
 893 KBUILD_CFLAGS   += $(call cc-option,-Werror=strict-prototypes)
 894
 895 # Prohibit date/time macros, which would make the build non-deterministic
 896 KBUILD_CFLAGS   += $(call cc-option,-Werror=date-time)
 897
 898 # enforce correct pointer usage
 899 KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)
 900
 901 # Require designated initializers for all marked structures
 902 KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)
 903
 904 # use the deterministic mode of AR if available
 905 KBUILD_ARFLAGS := $(call ar-option,D)
 906
 907 include scripts/Makefile.kasan
 908 include scripts/Makefile.extrawarn
 909 include scripts/Makefile.ubsan
 910
 911 # Add any arch overrides and user supplied CPPFLAGS, AFLAGS and CFLAGS as the
 912 # last assignments
 913 KBUILD_CPPFLAGS += $(ARCH_CPPFLAGS) $(KCPPFLAGS)
 914 KBUILD_AFLAGS   += $(ARCH_AFLAGS)   $(KAFLAGS)
 915 KBUILD_CFLAGS   += $(ARCH_CFLAGS)   $(KCFLAGS)
 916
 917 # Use --build-id when available.
 918 LDFLAGS_BUILD_ID := $(patsubst -Wl$(comma)%,%,\
 919                               $(call cc-ldoption, -Wl$(comma)--build-id,))
 920 KBUILD_LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID)
 921 LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)
 922
 923 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
 924 LDFLAGS_vmlinux += $(call ld-option, --gc-sections,)
 925 endif
 926
 927 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
 928 LDFLAGS_vmlinux += $(call ld-option, -X,)
 929 endif
 930
 931 # Default kernel image to build when no specific target is given.
 932 # KBUILD_IMAGE may be overruled on the command line or
 933 # set in the environment
 934 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
 935 # this default value
 936 export KBUILD_IMAGE ?= vmlinux
 937
 938 #
 939 # INSTALL_PATH specifies where to place the updated kernel and system map
 940 # images. Default is /boot, but you can set it to other values
 941 export  INSTALL_PATH ?= /boot
 942
 943 #
 944 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
 945 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
 946 # an argument if needed. Otherwise it defaults to the kernel install path
 947 #
 948 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
 949
 950 #
 951 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
 952 # relocations required by build roots.  This is not defined in the
 953 # makefile but the argument can be passed to make if needed.
 954 #
 955
 956 MODLIB  = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
 957 export MODLIB
 958
 959 #
 960 # INSTALL_MOD_STRIP, if defined, will cause modules to be
 961 # stripped after they are installed.  If INSTALL_MOD_STRIP is '1', then
 962 # the default option --strip-debug will be used.  Otherwise,
 963 # INSTALL_MOD_STRIP value will be used as the options to the strip command.
 964
 965 ifdef INSTALL_MOD_STRIP
 966 ifeq ($(INSTALL_MOD_STRIP),1)
 967 mod_strip_cmd = $(STRIP) --strip-debug
 968 else
 969 mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
 970 endif # INSTALL_MOD_STRIP=1
 971 else
 972 mod_strip_cmd = true
 973 endif # INSTALL_MOD_STRIP
 974 export mod_strip_cmd
 975
 976 # CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
 977 # after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
 978 # or CONFIG_MODULE_COMPRESS_XZ.
 979
 980 mod_compress_cmd = true
 981 ifdef CONFIG_MODULE_COMPRESS
 982   ifdef CONFIG_MODULE_COMPRESS_GZIP
 983     mod_compress_cmd = gzip -n -f
 984   endif # CONFIG_MODULE_COMPRESS_GZIP
 985   ifdef CONFIG_MODULE_COMPRESS_XZ
 986     mod_compress_cmd = xz -f
 987   endif # CONFIG_MODULE_COMPRESS_XZ
 988 endif # CONFIG_MODULE_COMPRESS
 989 export mod_compress_cmd
 990
 991 # Select initial ramdisk compression format, default is gzip(1).
 992 # This shall be used by the dracut(8) tool while creating an initramfs image.
 993 #
 994 INITRD_COMPRESS-y                  := gzip
 995 INITRD_COMPRESS-$(CONFIG_RD_BZIP2) := bzip2
 996 INITRD_COMPRESS-$(CONFIG_RD_LZMA)  := lzma
 997 INITRD_COMPRESS-$(CONFIG_RD_XZ)    := xz
 998 INITRD_COMPRESS-$(CONFIG_RD_LZO)   := lzo
 999 INITRD_COMPRESS-$(CONFIG_RD_LZ4)   := lz4
1000 # do not export INITRD_COMPRESS, since we didn't actually
1001 # choose a sane default compression above.
1002 # export INITRD_COMPRESS := $(INITRD_COMPRESS-y)
1003
1004 ifdef CONFIG_MODULE_SIG_ALL
1005 $(eval $(call config_filename,MODULE_SIG_KEY))
1006
1007 mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
1008 else
1009 mod_sign_cmd = true
1010 endif
1011 export mod_sign_cmd
1012
1013 ifdef CONFIG_STACK_VALIDATION
1014   has_libelf := $(call try-run,\
1015                 echo "int main() {}" | $(HOSTCC) -xc -o /dev/null -lelf -,1,0)
1016   ifeq ($(has_libelf),1)
1017     objtool_target := tools/objtool FORCE
1018   else
1019     ifdef CONFIG_UNWINDER_ORC
1020       $(error "Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel")
1021     else
1022       $(warning "Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel")
1023     endif
1024     SKIP_STACK_VALIDATION := 1
1025     export SKIP_STACK_VALIDATION
1026   endif
1027 endif
1028
1029
1030 ifeq ($(KBUILD_EXTMOD),)
1031 core-y          += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
1032
1033 vmlinux-dirs    := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
1034                      $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
1035                      $(net-y) $(net-m) $(libs-y) $(libs-m) $(virt-y)))
1036
1037 vmlinux-alldirs := $(sort $(vmlinux-dirs) $(patsubst %/,%,$(filter %/, \
1038                      $(init-) $(core-) $(drivers-) $(net-) $(libs-) $(virt-))))
1039
1040 init-y          := $(patsubst %/, %/built-in.o, $(init-y))
1041 core-y          := $(patsubst %/, %/built-in.o, $(core-y))
1042 drivers-y       := $(patsubst %/, %/built-in.o, $(drivers-y))
1043 net-y           := $(patsubst %/, %/built-in.o, $(net-y))
1044 libs-y1         := $(patsubst %/, %/lib.a, $(libs-y))
1045 libs-y2         := $(filter-out %.a, $(patsubst %/, %/built-in.o, $(libs-y)))
1046 virt-y          := $(patsubst %/, %/built-in.o, $(virt-y))
1047
1048 # Externally visible symbols (used by link-vmlinux.sh)
1049 export KBUILD_VMLINUX_INIT := $(head-y) $(init-y)
1050 export KBUILD_VMLINUX_MAIN := $(core-y) $(libs-y2) $(drivers-y) $(net-y) $(virt-y)
1051 export KBUILD_VMLINUX_LIBS := $(libs-y1)
1052 export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1053 export LDFLAGS_vmlinux
1054 # used by scripts/package/Makefile
1055 export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) arch Documentation include samples scripts tools)
1056
1057 vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_INIT) $(KBUILD_VMLINUX_MAIN) $(KBUILD_VMLINUX_LIBS)
1058
1059 # Include targets which we want to execute sequentially if the rest of the
1060 # kernel build went well. If CONFIG_TRIM_UNUSED_KSYMS is set, this might be
1061 # evaluated more than once.
1062 PHONY += vmlinux_prereq
1063 vmlinux_prereq: $(vmlinux-deps) FORCE
1064 ifdef CONFIG_HEADERS_CHECK
1065         $(Q)$(MAKE) -f $(srctree)/Makefile headers_check
1066 endif
1067 ifdef CONFIG_GDB_SCRIPTS
1068         $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1069 endif
1070 ifdef CONFIG_TRIM_UNUSED_KSYMS
1071         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1072           "$(MAKE) -f $(srctree)/Makefile vmlinux"
1073 endif
1074
1075 # standalone target for easier testing
1076 include/generated/autoksyms.h: FORCE
1077         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh true
1078
1079 ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1080
1081 # Final link of vmlinux with optional arch pass after final link
1082 cmd_link-vmlinux =                                                 \
1083         $(CONFIG_SHELL) $< $(LD) $(LDFLAGS) $(LDFLAGS_vmlinux) ;    \
1084         $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1085
1086 vmlinux: scripts/link-vmlinux.sh vmlinux_prereq $(vmlinux-deps) FORCE
1087         +$(call if_changed,link-vmlinux)
1088
1089 # Build samples along the rest of the kernel
1090 ifdef CONFIG_SAMPLES
1091 vmlinux-dirs += samples
1092 endif
1093
1094 # The actual objects are generated when descending,
1095 # make sure no implicit rule kicks in
1096 $(sort $(vmlinux-deps)): $(vmlinux-dirs) ;
1097
1098 # Handle descending into subdirectories listed in $(vmlinux-dirs)
1099 # Preset locale variables to speed up the build process. Limit locale
1100 # tweaks to this spot to avoid wrong language settings when running
1101 # make menuconfig etc.
1102 # Error messages still appears in the original language
1103
1104 PHONY += $(vmlinux-dirs)
1105 $(vmlinux-dirs): prepare scripts
1106         $(Q)$(MAKE) $(build)=$@
1107
1108 define filechk_kernel.release
1109         echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1110 endef
1111
1112 # Store (new) KERNELRELEASE string in include/config/kernel.release
1113 include/config/kernel.release: include/config/auto.conf FORCE
1114         $(call filechk,kernel.release)
1115
1116
1117 # Things we need to do before we recursively start building the kernel
1118 # or the modules are listed in "prepare".
1119 # A multi level approach is used. prepareN is processed before prepareN-1.
1120 # archprepare is used in arch Makefiles and when processed asm symlink,
1121 # version.h and scripts_basic is processed / created.
1122
1123 # Listed in dependency order
1124 PHONY += prepare archprepare prepare0 prepare1 prepare2 prepare3
1125
1126 # prepare3 is used to check if we are building in a separate output directory,
1127 # and if so do:
1128 # 1) Check that make has not been executed in the kernel src $(srctree)
1129 prepare3: include/config/kernel.release
1130 ifneq ($(KBUILD_SRC),)
1131         @$(kecho) '  Using $(srctree) as source for kernel'
1132         $(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \
1133                 echo >&2 "  $(srctree) is not clean, please run 'make mrproper'"; \
1134                 echo >&2 "  in the '$(srctree)' directory.";\
1135                 /bin/false; \
1136         fi;
1137 endif
1138
1139 # prepare2 creates a makefile if using a separate output directory.
1140 # From this point forward, .config has been reprocessed, so any rules
1141 # that need to depend on updated CONFIG_* values can be checked here.
1142 prepare2: prepare3 prepare-compiler-check outputmakefile asm-generic
1143
1144 prepare1: prepare2 $(version_h) include/generated/utsrelease.h \
1145                    include/config/auto.conf
1146         $(cmd_crmodverdir)
1147
1148 archprepare: archheaders archscripts prepare1 scripts_basic
1149
1150 prepare0: archprepare gcc-plugins
1151         $(Q)$(MAKE) $(build)=.
1152
1153 # All the preparing..
1154 prepare: prepare0 prepare-objtool
1155
1156 # Support for using generic headers in asm-generic
1157 PHONY += asm-generic uapi-asm-generic
1158 asm-generic: uapi-asm-generic
1159         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
1160                     src=asm obj=arch/$(SRCARCH)/include/generated/asm
1161 uapi-asm-generic:
1162         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
1163                     src=uapi/asm obj=arch/$(SRCARCH)/include/generated/uapi/asm
1164
1165 PHONY += prepare-objtool
1166 prepare-objtool: $(objtool_target)
1167
1168 # Check for CONFIG flags that require compiler support. Abort the build
1169 # after .config has been processed, but before the kernel build starts.
1170 #
1171 # For security-sensitive CONFIG options, we don't want to fallback and/or
1172 # silently change which compiler flags will be used, since that leads to
1173 # producing kernels with different security feature characteristics
1174 # depending on the compiler used. (For example, "But I selected
1175 # CC_STACKPROTECTOR_STRONG! Why did it build with _REGULAR?!")
1176 PHONY += prepare-compiler-check
1177 prepare-compiler-check: FORCE
1178 # Make sure we're using a supported toolchain with LTO_CLANG
1179 ifdef CONFIG_LTO_CLANG
1180   ifneq ($(call clang-ifversion, -ge, 0500, y), y)
1181         @echo Cannot use CONFIG_LTO_CLANG: requires clang 5.0 or later >&2 && exit 1
1182   endif
1183   ifneq ($(call gold-ifversion, -ge, 112000000, y), y)
1184         @echo Cannot use CONFIG_LTO_CLANG: requires GNU gold 1.12 or later >&2 && exit 1
1185   endif
1186 endif
1187 # Make sure compiler supports LTO flags
1188 ifdef lto-flags
1189   ifeq ($(call cc-option, $(lto-flags)),)
1190         @echo Cannot use CONFIG_LTO: $(lto-flags) not supported by compiler \
1191                 >&2 && exit 1
1192   endif
1193 endif
1194 # Make sure compiler supports requested stack protector flag.
1195 ifdef stackp-name
1196   ifeq ($(call cc-option, $(stackp-flag)),)
1197         @echo Cannot use CONFIG_CC_STACKPROTECTOR_$(stackp-name): \
1198                   $(stackp-flag) not supported by compiler >&2 && exit 1
1199   endif
1200 endif
1201 # Make sure compiler does not have buggy stack-protector support.
1202 ifdef stackp-check
1203   ifneq ($(shell $(CONFIG_SHELL) $(stackp-check) $(CC) $(KBUILD_CPPFLAGS) $(biarch)),y)
1204         @echo Cannot use CONFIG_CC_STACKPROTECTOR_$(stackp-name): \
1205                   $(stackp-flag) available but compiler is broken >&2 && exit 1
1206   endif
1207 endif
1208 ifdef cfi-flags
1209   ifeq ($(call cc-option, $(cfi-flags)),)
1210         @echo Cannot use CONFIG_CFI: $(cfi-flags) not supported by compiler >&2 && exit 1
1211   endif
1212 endif
1213         @:
1214
1215 # Generate some files
1216 # ---------------------------------------------------------------------------
1217
1218 # KERNELRELEASE can change from a few different places, meaning version.h
1219 # needs to be updated, so this check is forced on all builds
1220
1221 uts_len := 64
1222 define filechk_utsrelease.h
1223         if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1224           echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1225           exit 1;                                                         \
1226         fi;                                                               \
1227         (echo \#define UTS_RELEASE \"$(KERNELRELEASE)\";)
1228 endef
1229
1230 define filechk_version.h
1231         (echo \#define LINUX_VERSION_CODE $(shell                         \
1232         expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1233         echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))';)
1234 endef
1235
1236 $(version_h): $(srctree)/Makefile FORCE
1237         $(call filechk,version.h)
1238         $(Q)rm -f $(old_version_h)
1239
1240 include/generated/utsrelease.h: include/config/kernel.release FORCE
1241         $(call filechk,utsrelease.h)
1242
1243 PHONY += headerdep
1244 headerdep:
1245         $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1246         $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1247
1248 # ---------------------------------------------------------------------------
1249 # Kernel headers
1250
1251 #Default location for installed headers
1252 export INSTALL_HDR_PATH = $(objtree)/usr
1253
1254 # If we do an all arch process set dst to include/arch-$(hdr-arch)
1255 hdr-dst = $(if $(KBUILD_HEADERS), dst=include/arch-$(hdr-arch), dst=include)
1256
1257 PHONY += archheaders
1258 archheaders:
1259
1260 PHONY += archscripts
1261 archscripts:
1262
1263 PHONY += __headers
1264 __headers: $(version_h) scripts_basic uapi-asm-generic archheaders archscripts
1265         $(Q)$(MAKE) $(build)=scripts build_unifdef
1266
1267 PHONY += headers_install_all
1268 headers_install_all:
1269         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh install
1270
1271 PHONY += headers_install
1272 headers_install: __headers
1273         $(if $(wildcard $(srctree)/arch/$(hdr-arch)/include/uapi/asm/Kbuild),, \
1274           $(error Headers not exportable for the $(SRCARCH) architecture))
1275         $(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include
1276         $(Q)$(MAKE) $(hdr-inst)=arch/$(hdr-arch)/include/uapi $(hdr-dst)
1277
1278 PHONY += headers_check_all
1279 headers_check_all: headers_install_all
1280         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh check
1281
1282 PHONY += headers_check
1283 headers_check: headers_install
1284         $(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include HDRCHECK=1
1285         $(Q)$(MAKE) $(hdr-inst)=arch/$(hdr-arch)/include/uapi $(hdr-dst) HDRCHECK=1
1286
1287 # ---------------------------------------------------------------------------
1288 # Kernel selftest
1289
1290 PHONY += kselftest
1291 kselftest:
1292         $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1293
1294 PHONY += kselftest-clean
1295 kselftest-clean:
1296         $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests clean
1297
1298 PHONY += kselftest-merge
1299 kselftest-merge:
1300         $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1301         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/kconfig/merge_config.sh \
1302                 -m $(objtree)/.config \
1303                 $(srctree)/tools/testing/selftests/*/config
1304         +$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1305
1306 # ---------------------------------------------------------------------------
1307 # Modules
1308
1309 ifdef CONFIG_MODULES
1310
1311 # By default, build modules as well
1312
1313 all: modules
1314
1315 # Build modules
1316 #
1317 # A module can be listed more than once in obj-m resulting in
1318 # duplicate lines in modules.order files.  Those are removed
1319 # using awk while concatenating to the final file.
1320
1321 PHONY += modules
1322 modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux) modules.builtin
1323         $(Q)$(AWK) '!x[$$0]++' $(vmlinux-dirs:%=$(objtree)/%/modules.order) > $(objtree)/modules.order
1324         @$(kecho) '  Building modules, stage 2.';
1325         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1326
1327 modules.builtin: $(vmlinux-dirs:%=%/modules.builtin)
1328         $(Q)$(AWK) '!x[$$0]++' $^ > $(objtree)/modules.builtin
1329
1330 %/modules.builtin: include/config/auto.conf
1331         $(Q)$(MAKE) $(modbuiltin)=$*
1332
1333
1334 # Target to prepare building external modules
1335 PHONY += modules_prepare
1336 modules_prepare: prepare scripts
1337
1338 # Target to install modules
1339 PHONY += modules_install
1340 modules_install: _modinst_ _modinst_post
1341
1342 PHONY += _modinst_
1343 _modinst_:
1344         @rm -rf $(MODLIB)/kernel
1345         @rm -f $(MODLIB)/source
1346         @mkdir -p $(MODLIB)/kernel
1347         @ln -s $(abspath $(srctree)) $(MODLIB)/source
1348         @if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
1349                 rm -f $(MODLIB)/build ; \
1350                 ln -s $(CURDIR) $(MODLIB)/build ; \
1351         fi
1352         @cp -f $(objtree)/modules.order $(MODLIB)/
1353         @cp -f $(objtree)/modules.builtin $(MODLIB)/
1354         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1355
1356 # This depmod is only for convenience to give the initial
1357 # boot a modules.dep even before / is mounted read-write.  However the
1358 # boot script depmod is the master version.
1359 PHONY += _modinst_post
1360 _modinst_post: _modinst_
1361         $(call cmd,depmod)
1362
1363 ifeq ($(CONFIG_MODULE_SIG), y)
1364 PHONY += modules_sign
1365 modules_sign:
1366         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1367 endif
1368
1369 else # CONFIG_MODULES
1370
1371 # Modules not configured
1372 # ---------------------------------------------------------------------------
1373
1374 PHONY += modules modules_install
1375 modules modules_install:
1376         @echo >&2
1377         @echo >&2 "The present kernel configuration has modules disabled."
1378         @echo >&2 "Type 'make config' and enable loadable module support."
1379         @echo >&2 "Then build a kernel with module support enabled."
1380         @echo >&2
1381         @exit 1
1382
1383 endif # CONFIG_MODULES
1384
1385 ###
1386 # Cleaning is done on three levels.
1387 # make clean     Delete most generated files
1388 #                Leave enough to build external modules
1389 # make mrproper  Delete the current configuration, and all generated files
1390 # make distclean Remove editor backup files, patch leftover files and the like
1391
1392 # Directories & files removed with 'make clean'
1393 CLEAN_DIRS  += $(MODVERDIR)
1394
1395 # Directories & files removed with 'make mrproper'
1396 MRPROPER_DIRS  += include/config usr/include include/generated          \
1397                   arch/*/include/generated .tmp_objdiff
1398 MRPROPER_FILES += .config .config.old .version .old_version \
1399                   Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS \
1400                   signing_key.pem signing_key.priv signing_key.x509     \
1401                   x509.genkey extra_certificates signing_key.x509.keyid \
1402                   signing_key.x509.signer vmlinux-gdb.py
1403
1404 # clean - Delete most, but leave enough to build external modules
1405 #
1406 clean: rm-dirs  := $(CLEAN_DIRS)
1407 clean: rm-files := $(CLEAN_FILES)
1408 clean-dirs      := $(addprefix _clean_, . $(vmlinux-alldirs) Documentation samples)
1409
1410 PHONY += $(clean-dirs) clean archclean vmlinuxclean
1411 $(clean-dirs):
1412         $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1413
1414 vmlinuxclean:
1415         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1416         $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1417
1418 clean: archclean vmlinuxclean
1419
1420 # mrproper - Delete all generated files, including .config
1421 #
1422 mrproper: rm-dirs  := $(wildcard $(MRPROPER_DIRS))
1423 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1424 mrproper-dirs      := $(addprefix _mrproper_,scripts)
1425
1426 PHONY += $(mrproper-dirs) mrproper archmrproper
1427 $(mrproper-dirs):
1428         $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1429
1430 mrproper: clean archmrproper $(mrproper-dirs)
1431         $(call cmd,rmdirs)
1432         $(call cmd,rmfiles)
1433
1434 # distclean
1435 #
1436 PHONY += distclean
1437
1438 distclean: mrproper
1439         @find $(srctree) $(RCS_FIND_IGNORE) \
1440                 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1441                 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1442                 -o -name 'core' \) \
1443                 -type f -print | xargs rm -f
1444
1445
1446 # Packaging of the kernel to various formats
1447 # ---------------------------------------------------------------------------
1448 # rpm target kept for backward compatibility
1449 package-dir     := scripts/package
1450
1451 %src-pkg: FORCE
1452         $(Q)$(MAKE) $(build)=$(package-dir) $@
1453 %pkg: include/config/kernel.release FORCE
1454         $(Q)$(MAKE) $(build)=$(package-dir) $@
1455 rpm: include/config/kernel.release FORCE
1456         $(Q)$(MAKE) $(build)=$(package-dir) $@
1457
1458
1459 # Brief documentation of the typical targets used
1460 # ---------------------------------------------------------------------------
1461
1462 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1463 boards := $(sort $(notdir $(boards)))
1464 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1465 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1466
1467 PHONY += help
1468 help:
1469         @echo  'Cleaning targets:'
1470         @echo  '  clean           - Remove most generated files but keep the config and'
1471         @echo  '                    enough build support to build external modules'
1472         @echo  '  mrproper        - Remove all generated files + config + various backup files'
1473         @echo  '  distclean       - mrproper + remove editor backup and patch files'
1474         @echo  ''
1475         @echo  'Configuration targets:'
1476         @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1477         @echo  ''
1478         @echo  'Other generic targets:'
1479         @echo  '  all             - Build all targets marked with [*]'
1480         @echo  '* vmlinux         - Build the bare kernel'
1481         @echo  '* modules         - Build all modules'
1482         @echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1483         @echo  '  dir/            - Build all files in dir and below'
1484         @echo  '  dir/file.[ois]  - Build specified target only'
1485         @echo  '  dir/file.ll     - Build the LLVM assembly file'
1486         @echo  '                    (requires compiler support for LLVM assembly generation)'
1487         @echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1488         @echo  '                    (requires a recent binutils and recent build (System.map))'
1489         @echo  '  dir/file.ko     - Build module including final link'
1490         @echo  '  modules_prepare - Set up for building external modules'
1491         @echo  '  tags/TAGS       - Generate tags file for editors'
1492         @echo  '  cscope          - Generate cscope index'
1493         @echo  '  gtags           - Generate GNU GLOBAL index'
1494         @echo  '  kernelrelease   - Output the release version string (use with make -s)'
1495         @echo  '  kernelversion   - Output the version stored in Makefile (use with make -s)'
1496         @echo  '  image_name      - Output the image name (use with make -s)'
1497         @echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1498          echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1499          echo  ''
1500         @echo  'Static analysers:'
1501         @echo  '  checkstack      - Generate a list of stack hogs'
1502         @echo  '  namespacecheck  - Name space analysis on compiled kernel'
1503         @echo  '  versioncheck    - Sanity check on version.h usage'
1504         @echo  '  includecheck    - Check for duplicate included header files'
1505         @echo  '  export_report   - List the usages of all exported symbols'
1506         @echo  '  headers_check   - Sanity check on exported headers'
1507         @echo  '  headerdep       - Detect inclusion cycles in headers'
1508         @$(MAKE) -f $(srctree)/scripts/Makefile.help checker-help
1509         @echo  ''
1510         @echo  'Kernel selftest:'
1511         @echo  '  kselftest       - Build and run kernel selftest (run as root)'
1512         @echo  '                    Build, install, and boot kernel before'
1513         @echo  '                    running kselftest on it'
1514         @echo  '  kselftest-clean - Remove all generated kselftest files'
1515         @echo  '  kselftest-merge - Merge all the config dependencies of kselftest to existing'
1516         @echo  '                    .config.'
1517         @echo  ''
1518         @echo 'Userspace tools targets:'
1519         @echo '  use "make tools/help"'
1520         @echo '  or  "cd tools; make help"'
1521         @echo  ''
1522         @echo  'Kernel packaging:'
1523         @$(MAKE) $(build)=$(package-dir) help
1524         @echo  ''
1525         @echo  'Documentation targets:'
1526         @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1527         @echo  ''
1528         @echo  'Architecture specific targets ($(SRCARCH)):'
1529         @$(if $(archhelp),$(archhelp),\
1530                 echo '  No architecture specific help defined for $(SRCARCH)')
1531         @echo  ''
1532         @$(if $(boards), \
1533                 $(foreach b, $(boards), \
1534                 printf "  %-24s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1535                 echo '')
1536         @$(if $(board-dirs), \
1537                 $(foreach b, $(board-dirs), \
1538                 printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1539                 printf "  %-16s - Show all of the above\\n" help-boards; \
1540                 echo '')
1541
1542         @echo  '  make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1543         @echo  '  make V=2   [targets] 2 => give reason for rebuild of target'
1544         @echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1545         @echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK (sparse by default)'
1546         @echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1547         @echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1548         @echo  '  make W=n   [targets] Enable extra gcc checks, n=1,2,3 where'
1549         @echo  '                1: warnings which may be relevant and do not occur too often'
1550         @echo  '                2: warnings which occur quite often but may still be relevant'
1551         @echo  '                3: more obscure warnings, can most likely be ignored'
1552         @echo  '                Multiple levels can be combined with W=12 or W=123'
1553         @echo  ''
1554         @echo  'Execute "make" or "make all" to build all targets marked with [*] '
1555         @echo  'For further info see the ./README file'
1556
1557
1558 help-board-dirs := $(addprefix help-,$(board-dirs))
1559
1560 help-boards: $(help-board-dirs)
1561
1562 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1563
1564 $(help-board-dirs): help-%:
1565         @echo  'Architecture specific targets ($(SRCARCH) $*):'
1566         @$(if $(boards-per-dir), \
1567                 $(foreach b, $(boards-per-dir), \
1568                 printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1569                 echo '')
1570
1571
1572 # Documentation targets
1573 # ---------------------------------------------------------------------------
1574 DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs linkcheckdocs
1575 PHONY += $(DOC_TARGETS)
1576 $(DOC_TARGETS): scripts_basic FORCE
1577         $(Q)$(MAKE) $(build)=Documentation $@
1578
1579 else # KBUILD_EXTMOD
1580
1581 ###
1582 # External module support.
1583 # When building external modules the kernel used as basis is considered
1584 # read-only, and no consistency checks are made and the make
1585 # system is not used on the basis kernel. If updates are required
1586 # in the basis kernel ordinary make commands (without M=...) must
1587 # be used.
1588 #
1589 # The following are the only valid targets when building external
1590 # modules.
1591 # make M=dir clean     Delete all automatically generated files
1592 # make M=dir modules   Make all modules in specified dir
1593 # make M=dir           Same as 'make M=dir modules'
1594 # make M=dir modules_install
1595 #                      Install the modules built in the module directory
1596 #                      Assumes install directory is already created
1597
1598 # We are always building modules
1599 KBUILD_MODULES := 1
1600 PHONY += crmodverdir
1601 crmodverdir:
1602         $(cmd_crmodverdir)
1603
1604 PHONY += $(objtree)/Module.symvers
1605 $(objtree)/Module.symvers:
1606         @test -e $(objtree)/Module.symvers || ( \
1607         echo; \
1608         echo "  WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1609         echo "           is missing; modules will have no dependencies and modversions."; \
1610         echo )
1611
1612 module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
1613 PHONY += $(module-dirs) modules
1614 $(module-dirs): crmodverdir $(objtree)/Module.symvers
1615         $(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@)
1616
1617 modules: $(module-dirs)
1618         @$(kecho) '  Building modules, stage 2.';
1619         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1620
1621 PHONY += modules_install
1622 modules_install: _emodinst_ _emodinst_post
1623
1624 install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1625 PHONY += _emodinst_
1626 _emodinst_:
1627         $(Q)mkdir -p $(MODLIB)/$(install-dir)
1628         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1629
1630 PHONY += _emodinst_post
1631 _emodinst_post: _emodinst_
1632         $(call cmd,depmod)
1633
1634 clean-dirs := $(addprefix _clean_,$(KBUILD_EXTMOD))
1635
1636 PHONY += $(clean-dirs) clean
1637 $(clean-dirs):
1638         $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1639
1640 clean:  rm-dirs := $(MODVERDIR)
1641 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers
1642
1643 PHONY += help
1644 help:
1645         @echo  '  Building external modules.'
1646         @echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1647         @echo  ''
1648         @echo  '  modules         - default target, build the module(s)'
1649         @echo  '  modules_install - install the module'
1650         @echo  '  clean           - remove generated files in module directory only'
1651         @echo  ''
1652
1653 # Dummies...
1654 PHONY += prepare scripts
1655 prepare: ;
1656 scripts: ;
1657 endif # KBUILD_EXTMOD
1658
1659 clean: $(clean-dirs)
1660         $(call cmd,rmdirs)
1661         $(call cmd,rmfiles)
1662         @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1663                 \( -name '*.[oas]' -o -name '*.ko' -o -name '.*.cmd' \
1664                 -o -name '*.ko.*' \
1665                 -o -name '*.dwo'  \
1666                 -o -name '*.su'  \
1667                 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1668                 -o -name '*.symtypes' -o -name 'modules.order' \
1669                 -o -name modules.builtin -o -name '.tmp_*.o.*' \
1670                 -o -name '*.c.[012]*.*' \
1671                 -o -name '*.ll' \
1672                 -o -name '*.gcno' \
1673                 -o -name '*.*.symversions' \) -type f -print | xargs rm -f
1674
1675 # Generate tags for editors
1676 # ---------------------------------------------------------------------------
1677 quiet_cmd_tags = GEN     $@
1678       cmd_tags = $(CONFIG_SHELL) $(srctree)/scripts/tags.sh $@
1679
1680 tags TAGS cscope gtags: FORCE
1681         $(call cmd,tags)
1682
1683 # Scripts to check various things for consistency
1684 # ---------------------------------------------------------------------------
1685
1686 PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1687
1688 includecheck:
1689         find $(srctree)/* $(RCS_FIND_IGNORE) \
1690                 -name '*.[hcS]' -type f -print | sort \
1691                 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1692
1693 versioncheck:
1694         find $(srctree)/* $(RCS_FIND_IGNORE) \
1695                 -name '*.[hcS]' -type f -print | sort \
1696                 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1697
1698 coccicheck:
1699         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/$@
1700
1701 namespacecheck:
1702         $(PERL) $(srctree)/scripts/namespace.pl
1703
1704 export_report:
1705         $(PERL) $(srctree)/scripts/export_report.pl
1706
1707 endif #ifeq ($(config-targets),1)
1708 endif #ifeq ($(mixed-targets),1)
1709
1710 PHONY += checkstack kernelrelease kernelversion image_name
1711
1712 # UML needs a little special treatment here.  It wants to use the host
1713 # toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
1714 # else wants $(ARCH), including people doing cross-builds, which means
1715 # that $(SUBARCH) doesn't work here.
1716 ifeq ($(ARCH), um)
1717 CHECKSTACK_ARCH := $(SUBARCH)
1718 else
1719 CHECKSTACK_ARCH := $(ARCH)
1720 endif
1721 checkstack:
1722         $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1723         $(PERL) $(src)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1724
1725 kernelrelease:
1726         @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1727
1728 kernelversion:
1729         @echo $(KERNELVERSION)
1730
1731 image_name:
1732         @echo $(KBUILD_IMAGE)
1733
1734 # Clear a bunch of variables before executing the submake
1735 tools/: FORCE
1736         $(Q)mkdir -p $(objtree)/tools
1737         $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(src)/tools/
1738
1739 tools/%: FORCE
1740         $(Q)mkdir -p $(objtree)/tools
1741         $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(src)/tools/ $*
1742
1743 # Single targets
1744 # ---------------------------------------------------------------------------
1745 # Single targets are compatible with:
1746 # - build with mixed source and output
1747 # - build with separate output dir 'make O=...'
1748 # - external modules
1749 #
1750 #  target-dir => where to store outputfile
1751 #  build-dir  => directory in kernel source tree to use
1752
1753 ifeq ($(KBUILD_EXTMOD),)
1754         build-dir  = $(patsubst %/,%,$(dir $@))
1755         target-dir = $(dir $@)
1756 else
1757         zap-slash=$(filter-out .,$(patsubst %/,%,$(dir $@)))
1758         build-dir  = $(KBUILD_EXTMOD)$(if $(zap-slash),/$(zap-slash))
1759         target-dir = $(if $(KBUILD_EXTMOD),$(dir $<),$(dir $@))
1760 endif
1761
1762 %.s: %.c prepare scripts FORCE
1763         $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1764 %.i: %.c prepare scripts FORCE
1765         $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1766 %.o: %.c prepare scripts FORCE
1767         $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1768 %.lst: %.c prepare scripts FORCE
1769         $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1770 %.s: %.S prepare scripts FORCE
1771         $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1772 %.o: %.S prepare scripts FORCE
1773         $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1774 %.symtypes: %.c prepare scripts FORCE
1775         $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1776 %.ll: %.c prepare scripts FORCE
1777         $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1778
1779 # Modules
1780 /: prepare scripts FORCE
1781         $(cmd_crmodverdir)
1782         $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1783         $(build)=$(build-dir)
1784 # Make sure the latest headers are built for Documentation
1785 Documentation/ samples/: headers_install
1786 %/: prepare scripts FORCE
1787         $(cmd_crmodverdir)
1788         $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1789         $(build)=$(build-dir)
1790 %.ko: prepare scripts FORCE
1791         $(cmd_crmodverdir)
1792         $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1)   \
1793         $(build)=$(build-dir) $(@:.ko=.o)
1794         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1795
1796 # FIXME Should go into a make.lib or something
1797 # ===========================================================================
1798
1799 quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN   $(wildcard $(rm-dirs)))
1800       cmd_rmdirs = rm -rf $(rm-dirs)
1801
1802 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
1803       cmd_rmfiles = rm -f $(rm-files)
1804
1805 # Run depmod only if we have System.map and depmod is executable
1806 quiet_cmd_depmod = DEPMOD  $(KERNELRELEASE)
1807       cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1808                    $(KERNELRELEASE) "$(patsubst y,_,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX))"
1809
1810 # Create temporary dir for module support files
1811 # clean it up only when building all modules
1812 cmd_crmodverdir = $(Q)mkdir -p $(MODVERDIR) \
1813                   $(if $(KBUILD_MODULES),; rm -f $(MODVERDIR)/*)
1814
1815 # read all saved command lines
1816
1817 targets := $(wildcard $(sort $(targets)))
1818 cmd_files := $(wildcard .*.cmd $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
1819
1820 ifneq ($(cmd_files),)
1821   $(cmd_files): ;       # Do not try to update included dependency files
1822   include $(cmd_files)
1823 endif
1824
1825 endif   # skip-makefile
1826
1827 PHONY += FORCE
1828 FORCE:
1829
1830 # Declare the contents of the .PHONY variable as phony.  We keep that
1831 # information in a variable so we can use it in if_changed and friends.
1832 .PHONY: $(PHONY)