Makefile

   1 # SPDX-License-Identifier: GPL-2.0
   2 VERSION = 6
   3 PATCHLEVEL = 6
   4 SUBLEVEL = 0
   5 EXTRAVERSION = -rc5
   6 NAME = Hurr durr I'ma ninja sloth
   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 ifeq ($(filter undefine,$(.FEATURES)),)
  15 $(error GNU Make >= 3.82 is required. Your Make version is $(MAKE_VERSION))
  16 endif
  17
  18 $(if $(filter __%, $(MAKECMDGOALS)), \
  19         $(error targets prefixed with '__' are only for internal use))
  20
  21 # That's our default target when none is given on the command line
  22 PHONY := __all
  23 __all:
  24
  25 # We are using a recursive build, so we need to do a little thinking
  26 # to get the ordering right.
  27 #
  28 # Most importantly: sub-Makefiles should only ever modify files in
  29 # their own directory. If in some directory we have a dependency on
  30 # a file in another dir (which doesn't happen often, but it's often
  31 # unavoidable when linking the built-in.a targets which finally
  32 # turn into vmlinux), we will call a sub make in that other dir, and
  33 # after that we are sure that everything which is in that other dir
  34 # is now up to date.
  35 #
  36 # The only cases where we need to modify files which have global
  37 # effects are thus separated out and done before the recursive
  38 # descending is started. They are now explicitly listed as the
  39 # prepare rule.
  40
  41 this-makefile := $(lastword $(MAKEFILE_LIST))
  42 export abs_srctree := $(realpath $(dir $(this-makefile)))
  43 export abs_objtree := $(CURDIR)
  44
  45 ifneq ($(sub_make_done),1)
  46
  47 # Do not use make's built-in rules and variables
  48 # (this increases performance and avoids hard-to-debug behaviour)
  49 MAKEFLAGS += -rR
  50
  51 # Avoid funny character set dependencies
  52 unexport LC_ALL
  53 LC_COLLATE=C
  54 LC_NUMERIC=C
  55 export LC_COLLATE LC_NUMERIC
  56
  57 # Avoid interference with shell env settings
  58 unexport GREP_OPTIONS
  59
  60 # Beautify output
  61 # ---------------------------------------------------------------------------
  62 #
  63 # Most of build commands in Kbuild start with "cmd_". You can optionally define
  64 # "quiet_cmd_*". If defined, the short log is printed. Otherwise, no log from
  65 # that command is printed by default.
  66 #
  67 # e.g.)
  68 #    quiet_cmd_depmod = DEPMOD  $(MODLIB)
  69 #          cmd_depmod = $(srctree)/scripts/depmod.sh $(DEPMOD) $(KERNELRELEASE)
  70 #
  71 # A simple variant is to prefix commands with $(Q) - that's useful
  72 # for commands that shall be hidden in non-verbose mode.
  73 #
  74 #    $(Q)$(MAKE) $(build)=scripts/basic
  75 #
  76 # If KBUILD_VERBOSE contains 1, the whole command is echoed.
  77 # If KBUILD_VERBOSE contains 2, the reason for rebuilding is printed.
  78 #
  79 # To put more focus on warnings, be less verbose as default
  80 # Use 'make V=1' to see the full commands
  81
  82 ifeq ("$(origin V)", "command line")
  83   KBUILD_VERBOSE = $(V)
  84 endif
  85
  86 quiet = quiet_
  87 Q = @
  88
  89 ifneq ($(findstring 1, $(KBUILD_VERBOSE)),)
  90   quiet =
  91   Q =
  92 endif
  93
  94 # If the user is running make -s (silent mode), suppress echoing of
  95 # commands
  96 # make-4.0 (and later) keep single letter options in the 1st word of MAKEFLAGS.
  97
  98 ifeq ($(filter 3.%,$(MAKE_VERSION)),)
  99 short-opts := $(firstword -$(MAKEFLAGS))
 100 else
 101 short-opts := $(filter-out --%,$(MAKEFLAGS))
 102 endif
 103
 104 ifneq ($(findstring s,$(short-opts)),)
 105 quiet=silent_
 106 override KBUILD_VERBOSE :=
 107 endif
 108
 109 export quiet Q KBUILD_VERBOSE
 110
 111 # Call a source code checker (by default, "sparse") as part of the
 112 # C compilation.
 113 #
 114 # Use 'make C=1' to enable checking of only re-compiled files.
 115 # Use 'make C=2' to enable checking of *all* source files, regardless
 116 # of whether they are re-compiled or not.
 117 #
 118 # See the file "Documentation/dev-tools/sparse.rst" for more details,
 119 # including where to get the "sparse" utility.
 120
 121 ifeq ("$(origin C)", "command line")
 122   KBUILD_CHECKSRC = $(C)
 123 endif
 124 ifndef KBUILD_CHECKSRC
 125   KBUILD_CHECKSRC = 0
 126 endif
 127
 128 export KBUILD_CHECKSRC
 129
 130 # Enable "clippy" (a linter) as part of the Rust compilation.
 131 #
 132 # Use 'make CLIPPY=1' to enable it.
 133 ifeq ("$(origin CLIPPY)", "command line")
 134   KBUILD_CLIPPY := $(CLIPPY)
 135 endif
 136
 137 export KBUILD_CLIPPY
 138
 139 # Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
 140 # directory of external module to build. Setting M= takes precedence.
 141 ifeq ("$(origin M)", "command line")
 142   KBUILD_EXTMOD := $(M)
 143 endif
 144
 145 $(if $(word 2, $(KBUILD_EXTMOD)), \
 146         $(error building multiple external modules is not supported))
 147
 148 $(foreach x, % :, $(if $(findstring $x, $(KBUILD_EXTMOD)), \
 149         $(error module directory path cannot contain '$x')))
 150
 151 # Remove trailing slashes
 152 ifneq ($(filter %/, $(KBUILD_EXTMOD)),)
 153 KBUILD_EXTMOD := $(shell dirname $(KBUILD_EXTMOD).)
 154 endif
 155
 156 export KBUILD_EXTMOD
 157
 158 # Kbuild will save output files in the current working directory.
 159 # This does not need to match to the root of the kernel source tree.
 160 #
 161 # For example, you can do this:
 162 #
 163 #  cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
 164 #
 165 # If you want to save output files in a different location, there are
 166 # two syntaxes to specify it.
 167 #
 168 # 1) O=
 169 # Use "make O=dir/to/store/output/files/"
 170 #
 171 # 2) Set KBUILD_OUTPUT
 172 # Set the environment variable KBUILD_OUTPUT to point to the output directory.
 173 # export KBUILD_OUTPUT=dir/to/store/output/files/; make
 174 #
 175 # The O= assignment takes precedence over the KBUILD_OUTPUT environment
 176 # variable.
 177
 178 # Do we want to change the working directory?
 179 ifeq ("$(origin O)", "command line")
 180   KBUILD_OUTPUT := $(O)
 181 endif
 182
 183 ifneq ($(KBUILD_OUTPUT),)
 184 # Make's built-in functions such as $(abspath ...), $(realpath ...) cannot
 185 # expand a shell special character '~'. We use a somewhat tedious way here.
 186 abs_objtree := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) && pwd)
 187 $(if $(abs_objtree),, \
 188      $(error failed to create output directory "$(KBUILD_OUTPUT)"))
 189
 190 # $(realpath ...) resolves symlinks
 191 abs_objtree := $(realpath $(abs_objtree))
 192 endif # ifneq ($(KBUILD_OUTPUT),)
 193
 194 ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
 195 $(error source directory cannot contain spaces or colons)
 196 endif
 197
 198 ifneq ($(filter 3.%,$(MAKE_VERSION)),)
 199 # 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
 200 # We need to invoke sub-make to avoid implicit rules in the top Makefile.
 201 need-sub-make := 1
 202 # Cancel implicit rules for this Makefile.
 203 $(this-makefile): ;
 204 endif
 205
 206 export sub_make_done := 1
 207
 208 endif # sub_make_done
 209
 210 ifeq ($(abs_objtree),$(CURDIR))
 211 # Suppress "Entering directory ..." if we are at the final work directory.
 212 no-print-directory := --no-print-directory
 213 else
 214 # Recursion to show "Entering directory ..."
 215 need-sub-make := 1
 216 endif
 217
 218 ifeq ($(filter --no-print-directory, $(MAKEFLAGS)),)
 219 # If --no-print-directory is unset, recurse once again to set it.
 220 # You may end up recursing into __sub-make twice. This is needed due to the
 221 # behavior change in GNU Make 4.4.1.
 222 need-sub-make := 1
 223 endif
 224
 225 ifeq ($(need-sub-make),1)
 226
 227 PHONY += $(MAKECMDGOALS) __sub-make
 228
 229 $(filter-out $(this-makefile), $(MAKECMDGOALS)) __all: __sub-make
 230         @:
 231
 232 # Invoke a second make in the output directory, passing relevant variables
 233 __sub-make:
 234         $(Q)$(MAKE) $(no-print-directory) -C $(abs_objtree) \
 235         -f $(abs_srctree)/Makefile $(MAKECMDGOALS)
 236
 237 else # need-sub-make
 238
 239 # We process the rest of the Makefile if this is the final invocation of make
 240
 241 ifeq ($(abs_srctree),$(abs_objtree))
 242         # building in the source tree
 243         srctree := .
 244         building_out_of_srctree :=
 245 else
 246         ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
 247                 # building in a subdirectory of the source tree
 248                 srctree := ..
 249         else
 250                 srctree := $(abs_srctree)
 251         endif
 252         building_out_of_srctree := 1
 253 endif
 254
 255 ifneq ($(KBUILD_ABS_SRCTREE),)
 256 srctree := $(abs_srctree)
 257 endif
 258
 259 objtree         := .
 260 VPATH           := $(srctree)
 261
 262 export building_out_of_srctree srctree objtree VPATH
 263
 264 # To make sure we do not include .config for any of the *config targets
 265 # catch them early, and hand them over to scripts/kconfig/Makefile
 266 # It is allowed to specify more targets when calling make, including
 267 # mixing *config targets and build targets.
 268 # For example 'make oldconfig all'.
 269 # Detect when mixed targets is specified, and make a second invocation
 270 # of make so .config is not included in this case either (for *config).
 271
 272 version_h := include/generated/uapi/linux/version.h
 273
 274 clean-targets := %clean mrproper cleandocs
 275 no-dot-config-targets := $(clean-targets) \
 276                          cscope gtags TAGS tags help% %docs check% coccicheck \
 277                          $(version_h) headers headers_% archheaders archscripts \
 278                          %asm-generic kernelversion %src-pkg dt_binding_check \
 279                          outputmakefile rustavailable rustfmt rustfmtcheck
 280 # Installation targets should not require compiler. Unfortunately, vdso_install
 281 # is an exception where build artifacts may be updated. This must be fixed.
 282 no-compiler-targets := $(no-dot-config-targets) install dtbs_install \
 283                         headers_install modules_install modules_sign kernelrelease image_name
 284 no-sync-config-targets := $(no-dot-config-targets) %install modules_sign kernelrelease \
 285                           image_name
 286 single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.rsi %.s %.symtypes %/
 287
 288 config-build    :=
 289 mixed-build     :=
 290 need-config     := 1
 291 need-compiler   := 1
 292 may-sync-config := 1
 293 single-build    :=
 294
 295 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
 296         ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
 297                 need-config :=
 298         endif
 299 endif
 300
 301 ifneq ($(filter $(no-compiler-targets), $(MAKECMDGOALS)),)
 302         ifeq ($(filter-out $(no-compiler-targets), $(MAKECMDGOALS)),)
 303                 need-compiler :=
 304         endif
 305 endif
 306
 307 ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
 308         ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
 309                 may-sync-config :=
 310         endif
 311 endif
 312
 313 ifneq ($(KBUILD_EXTMOD),)
 314         may-sync-config :=
 315 endif
 316
 317 ifeq ($(KBUILD_EXTMOD),)
 318         ifneq ($(filter %config,$(MAKECMDGOALS)),)
 319                 config-build := 1
 320                 ifneq ($(words $(MAKECMDGOALS)),1)
 321                         mixed-build := 1
 322                 endif
 323         endif
 324 endif
 325
 326 # We cannot build single targets and the others at the same time
 327 ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
 328         single-build := 1
 329         ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
 330                 mixed-build := 1
 331         endif
 332 endif
 333
 334 # For "make -j clean all", "make -j mrproper defconfig all", etc.
 335 ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
 336         ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
 337                 mixed-build := 1
 338         endif
 339 endif
 340
 341 # install and modules_install need also be processed one by one
 342 ifneq ($(filter install,$(MAKECMDGOALS)),)
 343         ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
 344                 mixed-build := 1
 345         endif
 346 endif
 347
 348 ifdef mixed-build
 349 # ===========================================================================
 350 # We're called with mixed targets (*config and build targets).
 351 # Handle them one by one.
 352
 353 PHONY += $(MAKECMDGOALS) __build_one_by_one
 354
 355 $(MAKECMDGOALS): __build_one_by_one
 356         @:
 357
 358 __build_one_by_one:
 359         $(Q)set -e; \
 360         for i in $(MAKECMDGOALS); do \
 361                 $(MAKE) -f $(srctree)/Makefile $$i; \
 362         done
 363
 364 else # !mixed-build
 365
 366 include $(srctree)/scripts/Kbuild.include
 367
 368 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
 369 KERNELRELEASE = $(call read-file, include/config/kernel.release)
 370 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
 371 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
 372
 373 include $(srctree)/scripts/subarch.include
 374
 375 # Cross compiling and selecting different set of gcc/bin-utils
 376 # ---------------------------------------------------------------------------
 377 #
 378 # When performing cross compilation for other architectures ARCH shall be set
 379 # to the target architecture. (See arch/* for the possibilities).
 380 # ARCH can be set during invocation of make:
 381 # make ARCH=ia64
 382 # Another way is to have ARCH set in the environment.
 383 # The default ARCH is the host where make is executed.
 384
 385 # CROSS_COMPILE specify the prefix used for all executables used
 386 # during compilation. Only gcc and related bin-utils executables
 387 # are prefixed with $(CROSS_COMPILE).
 388 # CROSS_COMPILE can be set on the command line
 389 # make CROSS_COMPILE=ia64-linux-
 390 # Alternatively CROSS_COMPILE can be set in the environment.
 391 # Default value for CROSS_COMPILE is not to prefix executables
 392 # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
 393 ARCH            ?= $(SUBARCH)
 394
 395 # Architecture as present in compile.h
 396 UTS_MACHINE     := $(ARCH)
 397 SRCARCH         := $(ARCH)
 398
 399 # Additional ARCH settings for x86
 400 ifeq ($(ARCH),i386)
 401         SRCARCH := x86
 402 endif
 403 ifeq ($(ARCH),x86_64)
 404         SRCARCH := x86
 405 endif
 406
 407 # Additional ARCH settings for sparc
 408 ifeq ($(ARCH),sparc32)
 409        SRCARCH := sparc
 410 endif
 411 ifeq ($(ARCH),sparc64)
 412        SRCARCH := sparc
 413 endif
 414
 415 # Additional ARCH settings for parisc
 416 ifeq ($(ARCH),parisc64)
 417        SRCARCH := parisc
 418 endif
 419
 420 export cross_compiling :=
 421 ifneq ($(SRCARCH),$(SUBARCH))
 422 cross_compiling := 1
 423 endif
 424
 425 KCONFIG_CONFIG  ?= .config
 426 export KCONFIG_CONFIG
 427
 428 # SHELL used by kbuild
 429 CONFIG_SHELL := sh
 430
 431 HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
 432 HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
 433 HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
 434
 435 ifneq ($(LLVM),)
 436 ifneq ($(filter %/,$(LLVM)),)
 437 LLVM_PREFIX := $(LLVM)
 438 else ifneq ($(filter -%,$(LLVM)),)
 439 LLVM_SUFFIX := $(LLVM)
 440 endif
 441
 442 HOSTCC  = $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
 443 HOSTCXX = $(LLVM_PREFIX)clang++$(LLVM_SUFFIX)
 444 else
 445 HOSTCC  = gcc
 446 HOSTCXX = g++
 447 endif
 448 HOSTRUSTC = rustc
 449 HOSTPKG_CONFIG  = pkg-config
 450
 451 KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
 452                          -O2 -fomit-frame-pointer -std=gnu11
 453 KBUILD_USERCFLAGS  := $(KBUILD_USERHOSTCFLAGS) $(USERCFLAGS)
 454 KBUILD_USERLDFLAGS := $(USERLDFLAGS)
 455
 456 # These flags apply to all Rust code in the tree, including the kernel and
 457 # host programs.
 458 export rust_common_flags := --edition=2021 \
 459                             -Zbinary_dep_depinfo=y \
 460                             -Dunsafe_op_in_unsafe_fn -Drust_2018_idioms \
 461                             -Dunreachable_pub -Dnon_ascii_idents \
 462                             -Wmissing_docs \
 463                             -Drustdoc::missing_crate_level_docs \
 464                             -Dclippy::correctness -Dclippy::style \
 465                             -Dclippy::suspicious -Dclippy::complexity \
 466                             -Dclippy::perf \
 467                             -Dclippy::let_unit_value -Dclippy::mut_mut \
 468                             -Dclippy::needless_bitwise_bool \
 469                             -Dclippy::needless_continue \
 470                             -Dclippy::no_mangle_with_rust_abi \
 471                             -Wclippy::dbg_macro
 472
 473 KBUILD_HOSTCFLAGS   := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
 474 KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
 475 KBUILD_HOSTRUSTFLAGS := $(rust_common_flags) -O -Cstrip=debuginfo \
 476                         -Zallow-features= $(HOSTRUSTFLAGS)
 477 KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
 478 KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
 479
 480 # Make variables (CC, etc...)
 481 CPP             = $(CC) -E
 482 ifneq ($(LLVM),)
 483 CC              = $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
 484 LD              = $(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX)
 485 AR              = $(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX)
 486 NM              = $(LLVM_PREFIX)llvm-nm$(LLVM_SUFFIX)
 487 OBJCOPY         = $(LLVM_PREFIX)llvm-objcopy$(LLVM_SUFFIX)
 488 OBJDUMP         = $(LLVM_PREFIX)llvm-objdump$(LLVM_SUFFIX)
 489 READELF         = $(LLVM_PREFIX)llvm-readelf$(LLVM_SUFFIX)
 490 STRIP           = $(LLVM_PREFIX)llvm-strip$(LLVM_SUFFIX)
 491 else
 492 CC              = $(CROSS_COMPILE)gcc
 493 LD              = $(CROSS_COMPILE)ld
 494 AR              = $(CROSS_COMPILE)ar
 495 NM              = $(CROSS_COMPILE)nm
 496 OBJCOPY         = $(CROSS_COMPILE)objcopy
 497 OBJDUMP         = $(CROSS_COMPILE)objdump
 498 READELF         = $(CROSS_COMPILE)readelf
 499 STRIP           = $(CROSS_COMPILE)strip
 500 endif
 501 RUSTC           = rustc
 502 RUSTDOC         = rustdoc
 503 RUSTFMT         = rustfmt
 504 CLIPPY_DRIVER   = clippy-driver
 505 BINDGEN         = bindgen
 506 CARGO           = cargo
 507 PAHOLE          = pahole
 508 RESOLVE_BTFIDS  = $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
 509 LEX             = flex
 510 YACC            = bison
 511 AWK             = awk
 512 INSTALLKERNEL  := installkernel
 513 PERL            = perl
 514 PYTHON3         = python3
 515 CHECK           = sparse
 516 BASH            = bash
 517 KGZIP           = gzip
 518 KBZIP2          = bzip2
 519 KLZOP           = lzop
 520 LZMA            = lzma
 521 LZ4             = lz4c
 522 XZ              = xz
 523 ZSTD            = zstd
 524
 525 PAHOLE_FLAGS    = $(shell PAHOLE=$(PAHOLE) $(srctree)/scripts/pahole-flags.sh)
 526
 527 CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
 528                   -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
 529 NOSTDINC_FLAGS :=
 530 CFLAGS_MODULE   =
 531 RUSTFLAGS_MODULE =
 532 AFLAGS_MODULE   =
 533 LDFLAGS_MODULE  =
 534 CFLAGS_KERNEL   =
 535 RUSTFLAGS_KERNEL =
 536 AFLAGS_KERNEL   =
 537 LDFLAGS_vmlinux =
 538
 539 # Use USERINCLUDE when you must reference the UAPI directories only.
 540 USERINCLUDE    := \
 541                 -I$(srctree)/arch/$(SRCARCH)/include/uapi \
 542                 -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
 543                 -I$(srctree)/include/uapi \
 544                 -I$(objtree)/include/generated/uapi \
 545                 -include $(srctree)/include/linux/compiler-version.h \
 546                 -include $(srctree)/include/linux/kconfig.h
 547
 548 # Use LINUXINCLUDE when you must reference the include/ directory.
 549 # Needed to be compatible with the O= option
 550 LINUXINCLUDE    := \
 551                 -I$(srctree)/arch/$(SRCARCH)/include \
 552                 -I$(objtree)/arch/$(SRCARCH)/include/generated \
 553                 $(if $(building_out_of_srctree),-I$(srctree)/include) \
 554                 -I$(objtree)/include \
 555                 $(USERINCLUDE)
 556
 557 KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
 558
 559 KBUILD_CFLAGS :=
 560 KBUILD_CFLAGS += -std=gnu11
 561 KBUILD_CFLAGS += -fshort-wchar
 562 KBUILD_CFLAGS += -funsigned-char
 563 KBUILD_CFLAGS += -fno-common
 564 KBUILD_CFLAGS += -fno-PIE
 565 KBUILD_CFLAGS += -fno-strict-aliasing
 566
 567 KBUILD_CPPFLAGS := -D__KERNEL__
 568 KBUILD_RUSTFLAGS := $(rust_common_flags) \
 569                     --target=$(objtree)/scripts/target.json \
 570                     -Cpanic=abort -Cembed-bitcode=n -Clto=n \
 571                     -Cforce-unwind-tables=n -Ccodegen-units=1 \
 572                     -Csymbol-mangling-version=v0 \
 573                     -Crelocation-model=static \
 574                     -Zfunction-sections=n \
 575                     -Dclippy::float_arithmetic
 576
 577 KBUILD_AFLAGS_KERNEL :=
 578 KBUILD_CFLAGS_KERNEL :=
 579 KBUILD_RUSTFLAGS_KERNEL :=
 580 KBUILD_AFLAGS_MODULE  := -DMODULE
 581 KBUILD_CFLAGS_MODULE  := -DMODULE
 582 KBUILD_RUSTFLAGS_MODULE := --cfg MODULE
 583 KBUILD_LDFLAGS_MODULE :=
 584 KBUILD_LDFLAGS :=
 585 CLANG_FLAGS :=
 586
 587 ifeq ($(KBUILD_CLIPPY),1)
 588         RUSTC_OR_CLIPPY_QUIET := CLIPPY
 589         RUSTC_OR_CLIPPY = $(CLIPPY_DRIVER)
 590 else
 591         RUSTC_OR_CLIPPY_QUIET := RUSTC
 592         RUSTC_OR_CLIPPY = $(RUSTC)
 593 endif
 594
 595 ifdef RUST_LIB_SRC
 596         export RUST_LIB_SRC
 597 endif
 598
 599 # Allows the usage of unstable features in stable compilers.
 600 export RUSTC_BOOTSTRAP := 1
 601
 602 export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG
 603 export RUSTC RUSTDOC RUSTFMT RUSTC_OR_CLIPPY_QUIET RUSTC_OR_CLIPPY BINDGEN CARGO
 604 export HOSTRUSTC KBUILD_HOSTRUSTFLAGS
 605 export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
 606 export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
 607 export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
 608 export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
 609 export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS
 610
 611 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
 612 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
 613 export KBUILD_RUSTFLAGS RUSTFLAGS_KERNEL RUSTFLAGS_MODULE
 614 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
 615 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_RUSTFLAGS_MODULE KBUILD_LDFLAGS_MODULE
 616 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL KBUILD_RUSTFLAGS_KERNEL
 617 export PAHOLE_FLAGS
 618
 619 # Files to ignore in find ... statements
 620
 621 export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
 622                           -name CVS -o -name .pc -o -name .hg -o -name .git \) \
 623                           -prune -o
 624 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
 625                          --exclude CVS --exclude .pc --exclude .hg --exclude .git
 626
 627 # ===========================================================================
 628 # Rules shared between *config targets and build targets
 629
 630 # Basic helpers built in scripts/basic/
 631 PHONY += scripts_basic
 632 scripts_basic:
 633         $(Q)$(MAKE) $(build)=scripts/basic
 634
 635 PHONY += outputmakefile
 636 ifdef building_out_of_srctree
 637 # Before starting out-of-tree build, make sure the source tree is clean.
 638 # outputmakefile generates a Makefile in the output directory, if using a
 639 # separate output directory. This allows convenient use of make in the
 640 # output directory.
 641 # At the same time when output Makefile generated, generate .gitignore to
 642 # ignore whole output directory
 643
 644 quiet_cmd_makefile = GEN     Makefile
 645       cmd_makefile = { \
 646         echo "\# Automatically generated by $(srctree)/Makefile: don't edit"; \
 647         echo "include $(srctree)/Makefile"; \
 648         } > Makefile
 649
 650 outputmakefile:
 651         @if [ -f $(srctree)/.config -o \
 652                  -d $(srctree)/include/config -o \
 653                  -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
 654                 echo >&2 "***"; \
 655                 echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
 656                 echo >&2 "*** in $(abs_srctree)";\
 657                 echo >&2 "***"; \
 658                 false; \
 659         fi
 660         $(Q)ln -fsn $(srctree) source
 661         $(call cmd,makefile)
 662         $(Q)test -e .gitignore || \
 663         { echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
 664 endif
 665
 666 # The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
 667 # Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
 668 # CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
 669 # and from include/config/auto.conf.cmd to detect the compiler upgrade.
 670 CC_VERSION_TEXT = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1))
 671
 672 ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
 673 include $(srctree)/scripts/Makefile.clang
 674 endif
 675
 676 # Include this also for config targets because some architectures need
 677 # cc-cross-prefix to determine CROSS_COMPILE.
 678 ifdef need-compiler
 679 include $(srctree)/scripts/Makefile.compiler
 680 endif
 681
 682 ifdef config-build
 683 # ===========================================================================
 684 # *config targets only - make sure prerequisites are updated, and descend
 685 # in scripts/kconfig to make the *config target
 686
 687 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
 688 # KBUILD_DEFCONFIG may point out an alternative default configuration
 689 # used for 'make defconfig'
 690 include $(srctree)/arch/$(SRCARCH)/Makefile
 691 export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
 692
 693 config: outputmakefile scripts_basic FORCE
 694         $(Q)$(MAKE) $(build)=scripts/kconfig $@
 695
 696 %config: outputmakefile scripts_basic FORCE
 697         $(Q)$(MAKE) $(build)=scripts/kconfig $@
 698
 699 else #!config-build
 700 # ===========================================================================
 701 # Build targets only - this includes vmlinux, arch specific targets, clean
 702 # targets and others. In general all targets except *config targets.
 703
 704 # If building an external module we do not care about the all: rule
 705 # but instead __all depend on modules
 706 PHONY += all
 707 ifeq ($(KBUILD_EXTMOD),)
 708 __all: all
 709 else
 710 __all: modules
 711 endif
 712
 713 targets :=
 714
 715 # Decide whether to build built-in, modular, or both.
 716 # Normally, just do built-in.
 717
 718 KBUILD_MODULES :=
 719 KBUILD_BUILTIN := 1
 720
 721 # If we have only "make modules", don't compile built-in objects.
 722 ifeq ($(MAKECMDGOALS),modules)
 723   KBUILD_BUILTIN :=
 724 endif
 725
 726 # If we have "make <whatever> modules", compile modules
 727 # in addition to whatever we do anyway.
 728 # Just "make" or "make all" shall build modules as well
 729
 730 ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
 731   KBUILD_MODULES := 1
 732 endif
 733
 734 ifeq ($(MAKECMDGOALS),)
 735   KBUILD_MODULES := 1
 736 endif
 737
 738 export KBUILD_MODULES KBUILD_BUILTIN
 739
 740 ifdef need-config
 741 include include/config/auto.conf
 742 endif
 743
 744 ifeq ($(KBUILD_EXTMOD),)
 745 # Objects we will link into vmlinux / subdirs we need to visit
 746 core-y          :=
 747 drivers-y       :=
 748 libs-y          := lib/
 749 endif # KBUILD_EXTMOD
 750
 751 # The all: target is the default when no target is given on the
 752 # command line.
 753 # This allow a user to issue only 'make' to build a kernel including modules
 754 # Defaults to vmlinux, but the arch makefile usually adds further targets
 755 all: vmlinux
 756
 757 CFLAGS_GCOV     := -fprofile-arcs -ftest-coverage
 758 ifdef CONFIG_CC_IS_GCC
 759 CFLAGS_GCOV     += -fno-tree-loop-im
 760 endif
 761 export CFLAGS_GCOV
 762
 763 # The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
 764 ifdef CONFIG_FUNCTION_TRACER
 765   CC_FLAGS_FTRACE := -pg
 766 endif
 767
 768 include $(srctree)/arch/$(SRCARCH)/Makefile
 769
 770 ifdef need-config
 771 ifdef may-sync-config
 772 # Read in dependencies to all Kconfig* files, make sure to run syncconfig if
 773 # changes are detected. This should be included after arch/$(SRCARCH)/Makefile
 774 # because some architectures define CROSS_COMPILE there.
 775 include include/config/auto.conf.cmd
 776
 777 $(KCONFIG_CONFIG):
 778         @echo >&2 '***'
 779         @echo >&2 '*** Configuration file "$@" not found!'
 780         @echo >&2 '***'
 781         @echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
 782         @echo >&2 '*** "make menuconfig" or "make xconfig").'
 783         @echo >&2 '***'
 784         @/bin/false
 785
 786 # The actual configuration files used during the build are stored in
 787 # include/generated/ and include/config/. Update them if .config is newer than
 788 # include/config/auto.conf (which mirrors .config).
 789 #
 790 # This exploits the 'multi-target pattern rule' trick.
 791 # The syncconfig should be executed only once to make all the targets.
 792 # (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
 793 #
 794 # Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
 795 # so you cannot notice that Kconfig is waiting for the user input.
 796 %/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h %/generated/rustc_cfg: $(KCONFIG_CONFIG)
 797         $(Q)$(kecho) "  SYNC    $@"
 798         $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
 799 else # !may-sync-config
 800 # External modules and some install targets need include/generated/autoconf.h
 801 # and include/config/auto.conf but do not care if they are up-to-date.
 802 # Use auto.conf to trigger the test
 803 PHONY += include/config/auto.conf
 804
 805 include/config/auto.conf:
 806         @test -e include/generated/autoconf.h -a -e $@ || (             \
 807         echo >&2;                                                       \
 808         echo >&2 "  ERROR: Kernel configuration is invalid.";           \
 809         echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
 810         echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";      \
 811         echo >&2 ;                                                      \
 812         /bin/false)
 813
 814 endif # may-sync-config
 815 endif # need-config
 816
 817 KBUILD_CFLAGS   += -fno-delete-null-pointer-checks
 818
 819 ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
 820 KBUILD_CFLAGS += -O2
 821 KBUILD_RUSTFLAGS += -Copt-level=2
 822 else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
 823 KBUILD_CFLAGS += -Os
 824 KBUILD_RUSTFLAGS += -Copt-level=s
 825 endif
 826
 827 # Always set `debug-assertions` and `overflow-checks` because their default
 828 # depends on `opt-level` and `debug-assertions`, respectively.
 829 KBUILD_RUSTFLAGS += -Cdebug-assertions=$(if $(CONFIG_RUST_DEBUG_ASSERTIONS),y,n)
 830 KBUILD_RUSTFLAGS += -Coverflow-checks=$(if $(CONFIG_RUST_OVERFLOW_CHECKS),y,n)
 831
 832 # Tell gcc to never replace conditional load with a non-conditional one
 833 ifdef CONFIG_CC_IS_GCC
 834 # gcc-10 renamed --param=allow-store-data-races=0 to
 835 # -fno-allow-store-data-races.
 836 KBUILD_CFLAGS   += $(call cc-option,--param=allow-store-data-races=0)
 837 KBUILD_CFLAGS   += $(call cc-option,-fno-allow-store-data-races)
 838 endif
 839
 840 ifdef CONFIG_READABLE_ASM
 841 # Disable optimizations that make assembler listings hard to read.
 842 # reorder blocks reorders the control in the function
 843 # ipa clone creates specialized cloned functions
 844 # partial inlining inlines only parts of functions
 845 KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
 846 endif
 847
 848 stackp-flags-y                                    := -fno-stack-protector
 849 stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
 850 stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
 851
 852 KBUILD_CFLAGS += $(stackp-flags-y)
 853
 854 KBUILD_RUSTFLAGS-$(CONFIG_WERROR) += -Dwarnings
 855 KBUILD_RUSTFLAGS += $(KBUILD_RUSTFLAGS-y)
 856
 857 ifdef CONFIG_FRAME_POINTER
 858 KBUILD_CFLAGS   += -fno-omit-frame-pointer -fno-optimize-sibling-calls
 859 KBUILD_RUSTFLAGS += -Cforce-frame-pointers=y
 860 else
 861 # Some targets (ARM with Thumb2, for example), can't be built with frame
 862 # pointers.  For those, we don't have FUNCTION_TRACER automatically
 863 # select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
 864 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
 865 # -fomit-frame-pointer with FUNCTION_TRACER.
 866 # In the Rust target specification, "frame-pointer" is set explicitly
 867 # to "may-omit".
 868 ifndef CONFIG_FUNCTION_TRACER
 869 KBUILD_CFLAGS   += -fomit-frame-pointer
 870 endif
 871 endif
 872
 873 # Initialize all stack variables with a 0xAA pattern.
 874 ifdef CONFIG_INIT_STACK_ALL_PATTERN
 875 KBUILD_CFLAGS   += -ftrivial-auto-var-init=pattern
 876 endif
 877
 878 # Initialize all stack variables with a zero value.
 879 ifdef CONFIG_INIT_STACK_ALL_ZERO
 880 KBUILD_CFLAGS   += -ftrivial-auto-var-init=zero
 881 ifdef CONFIG_CC_HAS_AUTO_VAR_INIT_ZERO_ENABLER
 882 # https://github.com/llvm/llvm-project/issues/44842
 883 CC_AUTO_VAR_INIT_ZERO_ENABLER := -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
 884 export CC_AUTO_VAR_INIT_ZERO_ENABLER
 885 KBUILD_CFLAGS   += $(CC_AUTO_VAR_INIT_ZERO_ENABLER)
 886 endif
 887 endif
 888
 889 # While VLAs have been removed, GCC produces unreachable stack probes
 890 # for the randomize_kstack_offset feature. Disable it for all compilers.
 891 KBUILD_CFLAGS   += $(call cc-option, -fno-stack-clash-protection)
 892
 893 # Clear used registers at func exit (to reduce data lifetime and ROP gadgets).
 894 ifdef CONFIG_ZERO_CALL_USED_REGS
 895 KBUILD_CFLAGS   += -fzero-call-used-regs=used-gpr
 896 endif
 897
 898 ifdef CONFIG_FUNCTION_TRACER
 899 ifdef CONFIG_FTRACE_MCOUNT_USE_CC
 900   CC_FLAGS_FTRACE       += -mrecord-mcount
 901   ifdef CONFIG_HAVE_NOP_MCOUNT
 902     ifeq ($(call cc-option-yn, -mnop-mcount),y)
 903       CC_FLAGS_FTRACE   += -mnop-mcount
 904       CC_FLAGS_USING    += -DCC_USING_NOP_MCOUNT
 905     endif
 906   endif
 907 endif
 908 ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
 909   ifdef CONFIG_HAVE_OBJTOOL_NOP_MCOUNT
 910     CC_FLAGS_USING      += -DCC_USING_NOP_MCOUNT
 911   endif
 912 endif
 913 ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
 914   ifdef CONFIG_HAVE_C_RECORDMCOUNT
 915     BUILD_C_RECORDMCOUNT := y
 916     export BUILD_C_RECORDMCOUNT
 917   endif
 918 endif
 919 ifdef CONFIG_HAVE_FENTRY
 920   # s390-linux-gnu-gcc did not support -mfentry until gcc-9.
 921   ifeq ($(call cc-option-yn, -mfentry),y)
 922     CC_FLAGS_FTRACE     += -mfentry
 923     CC_FLAGS_USING      += -DCC_USING_FENTRY
 924   endif
 925 endif
 926 export CC_FLAGS_FTRACE
 927 KBUILD_CFLAGS   += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
 928 KBUILD_AFLAGS   += $(CC_FLAGS_USING)
 929 endif
 930
 931 # We trigger additional mismatches with less inlining
 932 ifdef CONFIG_DEBUG_SECTION_MISMATCH
 933 KBUILD_CFLAGS += -fno-inline-functions-called-once
 934 endif
 935
 936 # `rustc`'s `-Zfunction-sections` applies to data too (as of 1.59.0).
 937 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
 938 KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
 939 KBUILD_RUSTFLAGS_KERNEL += -Zfunction-sections=y
 940 LDFLAGS_vmlinux += --gc-sections
 941 endif
 942
 943 ifdef CONFIG_SHADOW_CALL_STACK
 944 ifndef CONFIG_DYNAMIC_SCS
 945 CC_FLAGS_SCS    := -fsanitize=shadow-call-stack
 946 KBUILD_CFLAGS   += $(CC_FLAGS_SCS)
 947 endif
 948 export CC_FLAGS_SCS
 949 endif
 950
 951 ifdef CONFIG_LTO_CLANG
 952 ifdef CONFIG_LTO_CLANG_THIN
 953 CC_FLAGS_LTO    := -flto=thin -fsplit-lto-unit
 954 KBUILD_LDFLAGS  += --thinlto-cache-dir=$(extmod_prefix).thinlto-cache
 955 else
 956 CC_FLAGS_LTO    := -flto
 957 endif
 958 CC_FLAGS_LTO    += -fvisibility=hidden
 959
 960 # Limit inlining across translation units to reduce binary size
 961 KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
 962
 963 # Check for frame size exceeding threshold during prolog/epilog insertion
 964 # when using lld < 13.0.0.
 965 ifneq ($(CONFIG_FRAME_WARN),0)
 966 ifeq ($(call test-lt, $(CONFIG_LLD_VERSION), 130000),y)
 967 KBUILD_LDFLAGS  += -plugin-opt=-warn-stack-size=$(CONFIG_FRAME_WARN)
 968 endif
 969 endif
 970 endif
 971
 972 ifdef CONFIG_LTO
 973 KBUILD_CFLAGS   += -fno-lto $(CC_FLAGS_LTO)
 974 KBUILD_AFLAGS   += -fno-lto
 975 export CC_FLAGS_LTO
 976 endif
 977
 978 ifdef CONFIG_CFI_CLANG
 979 CC_FLAGS_CFI    := -fsanitize=kcfi
 980 KBUILD_CFLAGS   += $(CC_FLAGS_CFI)
 981 export CC_FLAGS_CFI
 982 endif
 983
 984 ifneq ($(CONFIG_FUNCTION_ALIGNMENT),0)
 985 KBUILD_CFLAGS += -falign-functions=$(CONFIG_FUNCTION_ALIGNMENT)
 986 endif
 987
 988 # arch Makefile may override CC so keep this after arch Makefile is included
 989 NOSTDINC_FLAGS += -nostdinc
 990
 991 # To gain proper coverage for CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE,
 992 # the kernel uses only C99 flexible arrays for dynamically sized trailing
 993 # arrays. Enforce this for everything that may examine structure sizes and
 994 # perform bounds checking.
 995 KBUILD_CFLAGS += $(call cc-option, -fstrict-flex-arrays=3)
 996
 997 # disable invalid "can't wrap" optimizations for signed / pointers
 998 KBUILD_CFLAGS   += -fno-strict-overflow
 999
1000 # Make sure -fstack-check isn't enabled (like gentoo apparently did)
1001 KBUILD_CFLAGS  += -fno-stack-check
1002
1003 # conserve stack if available
1004 ifdef CONFIG_CC_IS_GCC
1005 KBUILD_CFLAGS   += -fconserve-stack
1006 endif
1007
1008 # change __FILE__ to the relative path from the srctree
1009 KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
1010
1011 # include additional Makefiles when needed
1012 include-y                       := scripts/Makefile.extrawarn
1013 include-$(CONFIG_DEBUG_INFO)    += scripts/Makefile.debug
1014 include-$(CONFIG_KASAN)         += scripts/Makefile.kasan
1015 include-$(CONFIG_KCSAN)         += scripts/Makefile.kcsan
1016 include-$(CONFIG_KMSAN)         += scripts/Makefile.kmsan
1017 include-$(CONFIG_UBSAN)         += scripts/Makefile.ubsan
1018 include-$(CONFIG_KCOV)          += scripts/Makefile.kcov
1019 include-$(CONFIG_RANDSTRUCT)    += scripts/Makefile.randstruct
1020 include-$(CONFIG_GCC_PLUGINS)   += scripts/Makefile.gcc-plugins
1021
1022 include $(addprefix $(srctree)/, $(include-y))
1023
1024 # scripts/Makefile.gcc-plugins is intentionally included last.
1025 # Do not add $(call cc-option,...) below this line. When you build the kernel
1026 # from the clean source tree, the GCC plugins do not exist at this point.
1027
1028 # Add user supplied CPPFLAGS, AFLAGS, CFLAGS and RUSTFLAGS as the last assignments
1029 KBUILD_CPPFLAGS += $(KCPPFLAGS)
1030 KBUILD_AFLAGS   += $(KAFLAGS)
1031 KBUILD_CFLAGS   += $(KCFLAGS)
1032 KBUILD_RUSTFLAGS += $(KRUSTFLAGS)
1033
1034 KBUILD_LDFLAGS_MODULE += --build-id=sha1
1035 LDFLAGS_vmlinux += --build-id=sha1
1036
1037 KBUILD_LDFLAGS  += -z noexecstack
1038 ifeq ($(CONFIG_LD_IS_BFD),y)
1039 KBUILD_LDFLAGS  += $(call ld-option,--no-warn-rwx-segments)
1040 endif
1041
1042 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1043 LDFLAGS_vmlinux += -X
1044 endif
1045
1046 ifeq ($(CONFIG_RELR),y)
1047 # ld.lld before 15 did not support -z pack-relative-relocs.
1048 LDFLAGS_vmlinux += $(call ld-option,--pack-dyn-relocs=relr,-z pack-relative-relocs)
1049 endif
1050
1051 # We never want expected sections to be placed heuristically by the
1052 # linker. All sections should be explicitly named in the linker script.
1053 ifdef CONFIG_LD_ORPHAN_WARN
1054 LDFLAGS_vmlinux += --orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL)
1055 endif
1056
1057 # Align the bit size of userspace programs with the kernel
1058 KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1059 KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1060
1061 # make the checker run with the right architecture
1062 CHECKFLAGS += --arch=$(ARCH)
1063
1064 # insure the checker run with the right endianness
1065 CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1066
1067 # the checker needs the correct machine size
1068 CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1069
1070 # Default kernel image to build when no specific target is given.
1071 # KBUILD_IMAGE may be overruled on the command line or
1072 # set in the environment
1073 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
1074 # this default value
1075 export KBUILD_IMAGE ?= vmlinux
1076
1077 #
1078 # INSTALL_PATH specifies where to place the updated kernel and system map
1079 # images. Default is /boot, but you can set it to other values
1080 export  INSTALL_PATH ?= /boot
1081
1082 #
1083 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1084 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1085 # an argument if needed. Otherwise it defaults to the kernel install path
1086 #
1087 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1088
1089 #
1090 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1091 # relocations required by build roots.  This is not defined in the
1092 # makefile but the argument can be passed to make if needed.
1093 #
1094
1095 MODLIB  = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1096 export MODLIB
1097
1098 PHONY += prepare0
1099
1100 export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
1101 export MODORDER := $(extmod_prefix)modules.order
1102 export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
1103
1104 ifeq ($(KBUILD_EXTMOD),)
1105
1106 build-dir       := .
1107 clean-dirs      := $(sort . Documentation \
1108                      $(patsubst %/,%,$(filter %/, $(core-) \
1109                         $(drivers-) $(libs-))))
1110
1111 export ARCH_CORE        := $(core-y)
1112 export ARCH_LIB         := $(filter %/, $(libs-y))
1113 export ARCH_DRIVERS     := $(drivers-y) $(drivers-m)
1114 # Externally visible symbols (used by link-vmlinux.sh)
1115
1116 KBUILD_VMLINUX_OBJS := ./built-in.a
1117 ifdef CONFIG_MODULES
1118 KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1119 KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1120 else
1121 KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1122 endif
1123
1124 export KBUILD_VMLINUX_LIBS
1125 export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1126
1127 ifdef CONFIG_TRIM_UNUSED_KSYMS
1128 # For the kernel to actually contain only the needed exported symbols,
1129 # we have to build modules as well to determine what those symbols are.
1130 KBUILD_MODULES := 1
1131 endif
1132
1133 # '$(AR) mPi' needs 'T' to workaround the bug of llvm-ar <= 14
1134 quiet_cmd_ar_vmlinux.a = AR      $@
1135       cmd_ar_vmlinux.a = \
1136         rm -f $@; \
1137         $(AR) cDPrST $@ $(KBUILD_VMLINUX_OBJS); \
1138         $(AR) mPiT $$($(AR) t $@ | sed -n 1p) $@ $$($(AR) t $@ | grep -F -f $(srctree)/scripts/head-object-list.txt)
1139
1140 targets += vmlinux.a
1141 vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt FORCE
1142         $(call if_changed,ar_vmlinux.a)
1143
1144 PHONY += vmlinux_o
1145 vmlinux_o: vmlinux.a $(KBUILD_VMLINUX_LIBS)
1146         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o
1147
1148 vmlinux.o modules.builtin.modinfo modules.builtin: vmlinux_o
1149         @:
1150
1151 PHONY += vmlinux
1152 # LDFLAGS_vmlinux in the top Makefile defines linker flags for the top vmlinux,
1153 # not for decompressors. LDFLAGS_vmlinux in arch/*/boot/compressed/Makefile is
1154 # unrelated; the decompressors just happen to have the same base name,
1155 # arch/*/boot/compressed/vmlinux.
1156 # Export LDFLAGS_vmlinux only to scripts/Makefile.vmlinux.
1157 #
1158 # _LDFLAGS_vmlinux is a workaround for the 'private export' bug:
1159 #   https://savannah.gnu.org/bugs/?61463
1160 # For Make > 4.4, the following simple code will work:
1161 #  vmlinux: private export LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1162 vmlinux: private _LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1163 vmlinux: export LDFLAGS_vmlinux = $(_LDFLAGS_vmlinux)
1164 vmlinux: vmlinux.o $(KBUILD_LDS) modpost
1165         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux
1166
1167 # The actual objects are generated when descending,
1168 # make sure no implicit rule kicks in
1169 $(sort $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)): . ;
1170
1171 ifeq ($(origin KERNELRELEASE),file)
1172 filechk_kernel.release = $(srctree)/scripts/setlocalversion $(srctree)
1173 else
1174 filechk_kernel.release = echo $(KERNELRELEASE)
1175 endif
1176
1177 # Store (new) KERNELRELEASE string in include/config/kernel.release
1178 include/config/kernel.release: FORCE
1179         $(call filechk,kernel.release)
1180
1181 # Additional helpers built in scripts/
1182 # Carefully list dependencies so we do not try to build scripts twice
1183 # in parallel
1184 PHONY += scripts
1185 scripts: scripts_basic scripts_dtc
1186         $(Q)$(MAKE) $(build)=$(@)
1187
1188 # Things we need to do before we recursively start building the kernel
1189 # or the modules are listed in "prepare".
1190 # A multi level approach is used. prepareN is processed before prepareN-1.
1191 # archprepare is used in arch Makefiles and when processed asm symlink,
1192 # version.h and scripts_basic is processed / created.
1193
1194 PHONY += prepare archprepare
1195
1196 archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1197         asm-generic $(version_h) include/generated/utsrelease.h \
1198         include/generated/compile.h include/generated/autoconf.h remove-stale-files
1199
1200 prepare0: archprepare
1201         $(Q)$(MAKE) $(build)=scripts/mod
1202         $(Q)$(MAKE) $(build)=. prepare
1203
1204 # All the preparing..
1205 prepare: prepare0
1206 ifdef CONFIG_RUST
1207         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh
1208         $(Q)$(MAKE) $(build)=rust
1209 endif
1210
1211 PHONY += remove-stale-files
1212 remove-stale-files:
1213         $(Q)$(srctree)/scripts/remove-stale-files
1214
1215 # Support for using generic headers in asm-generic
1216 asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1217
1218 PHONY += asm-generic uapi-asm-generic
1219 asm-generic: uapi-asm-generic
1220         $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1221         generic=include/asm-generic
1222 uapi-asm-generic:
1223         $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1224         generic=include/uapi/asm-generic
1225
1226 # Generate some files
1227 # ---------------------------------------------------------------------------
1228
1229 # KERNELRELEASE can change from a few different places, meaning version.h
1230 # needs to be updated, so this check is forced on all builds
1231
1232 uts_len := 64
1233 define filechk_utsrelease.h
1234         if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1235           echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1236           exit 1;                                                         \
1237         fi;                                                               \
1238         echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1239 endef
1240
1241 define filechk_version.h
1242         if [ $(SUBLEVEL) -gt 255 ]; then                                 \
1243                 echo \#define LINUX_VERSION_CODE $(shell                 \
1244                 expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1245         else                                                             \
1246                 echo \#define LINUX_VERSION_CODE $(shell                 \
1247                 expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1248         fi;                                                              \
1249         echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
1250         ((c) > 255 ? 255 : (c)))';                                       \
1251         echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
1252         echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
1253         echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1254 endef
1255
1256 $(version_h): PATCHLEVEL := $(or $(PATCHLEVEL), 0)
1257 $(version_h): SUBLEVEL := $(or $(SUBLEVEL), 0)
1258 $(version_h): FORCE
1259         $(call filechk,version.h)
1260
1261 include/generated/utsrelease.h: include/config/kernel.release FORCE
1262         $(call filechk,utsrelease.h)
1263
1264 filechk_compile.h = $(srctree)/scripts/mkcompile_h \
1265         "$(UTS_MACHINE)" "$(CONFIG_CC_VERSION_TEXT)" "$(LD)"
1266
1267 include/generated/compile.h: FORCE
1268         $(call filechk,compile.h)
1269
1270 PHONY += headerdep
1271 headerdep:
1272         $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1273         $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1274
1275 # ---------------------------------------------------------------------------
1276 # Kernel headers
1277
1278 #Default location for installed headers
1279 export INSTALL_HDR_PATH = $(objtree)/usr
1280
1281 quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1282       cmd_headers_install = \
1283         mkdir -p $(INSTALL_HDR_PATH); \
1284         rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1285         usr/include $(INSTALL_HDR_PATH)
1286
1287 PHONY += headers_install
1288 headers_install: headers
1289         $(call cmd,headers_install)
1290
1291 PHONY += archheaders archscripts
1292
1293 hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1294
1295 PHONY += headers
1296 headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1297         $(if $(filter um, $(SRCARCH)), $(error Headers not exportable for UML))
1298         $(Q)$(MAKE) $(hdr-inst)=include/uapi
1299         $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1300
1301 ifdef CONFIG_HEADERS_INSTALL
1302 prepare: headers
1303 endif
1304
1305 PHONY += scripts_unifdef
1306 scripts_unifdef: scripts_basic
1307         $(Q)$(MAKE) $(build)=scripts scripts/unifdef
1308
1309 # ---------------------------------------------------------------------------
1310 # Install
1311
1312 # Many distributions have the custom install script, /sbin/installkernel.
1313 # If DKMS is installed, 'make install' will eventually recurse back
1314 # to this Makefile to build and install external modules.
1315 # Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
1316
1317 quiet_cmd_install = INSTALL $(INSTALL_PATH)
1318       cmd_install = unset sub_make_done; $(srctree)/scripts/install.sh
1319
1320 # ---------------------------------------------------------------------------
1321 # Tools
1322
1323 ifdef CONFIG_OBJTOOL
1324 prepare: tools/objtool
1325 endif
1326
1327 ifdef CONFIG_BPF
1328 ifdef CONFIG_DEBUG_INFO_BTF
1329 prepare: tools/bpf/resolve_btfids
1330 endif
1331 endif
1332
1333 PHONY += resolve_btfids_clean
1334
1335 resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1336
1337 # tools/bpf/resolve_btfids directory might not exist
1338 # in output directory, skip its clean in that case
1339 resolve_btfids_clean:
1340 ifneq ($(wildcard $(resolve_btfids_O)),)
1341         $(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1342 endif
1343
1344 # Clear a bunch of variables before executing the submake
1345 ifeq ($(quiet),silent_)
1346 tools_silent=s
1347 endif
1348
1349 tools/: FORCE
1350         $(Q)mkdir -p $(objtree)/tools
1351         $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1352
1353 tools/%: FORCE
1354         $(Q)mkdir -p $(objtree)/tools
1355         $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1356
1357 # ---------------------------------------------------------------------------
1358 # Kernel selftest
1359
1360 PHONY += kselftest
1361 kselftest: headers
1362         $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1363
1364 kselftest-%: headers FORCE
1365         $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1366
1367 PHONY += kselftest-merge
1368 kselftest-merge:
1369         $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1370         $(Q)find $(srctree)/tools/testing/selftests -name config | \
1371                 xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1372         $(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1373
1374 # ---------------------------------------------------------------------------
1375 # Devicetree files
1376
1377 ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1378 dtstree := arch/$(SRCARCH)/boot/dts
1379 endif
1380
1381 ifneq ($(dtstree),)
1382
1383 %.dtb: dtbs_prepare
1384         $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1385
1386 %.dtbo: dtbs_prepare
1387         $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1388
1389 PHONY += dtbs dtbs_prepare dtbs_install dtbs_check
1390 dtbs: dtbs_prepare
1391         $(Q)$(MAKE) $(build)=$(dtstree)
1392
1393 # include/config/kernel.release is actually needed when installing DTBs because
1394 # INSTALL_DTBS_PATH contains $(KERNELRELEASE). However, we do not want to make
1395 # dtbs_install depend on it as dtbs_install may run as root.
1396 dtbs_prepare: include/config/kernel.release scripts_dtc
1397
1398 ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1399 export CHECK_DTBS=y
1400 endif
1401
1402 ifneq ($(CHECK_DTBS),)
1403 dtbs_prepare: dt_binding_check
1404 endif
1405
1406 dtbs_check: dtbs
1407
1408 dtbs_install:
1409         $(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1410
1411 ifdef CONFIG_OF_EARLY_FLATTREE
1412 all: dtbs
1413 endif
1414
1415 endif
1416
1417 PHONY += scripts_dtc
1418 scripts_dtc: scripts_basic
1419         $(Q)$(MAKE) $(build)=scripts/dtc
1420
1421 ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1422 export CHECK_DT_BINDING=y
1423 endif
1424
1425 PHONY += dt_binding_check
1426 dt_binding_check: scripts_dtc
1427         $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1428
1429 PHONY += dt_compatible_check
1430 dt_compatible_check: dt_binding_check
1431         $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1432
1433 # ---------------------------------------------------------------------------
1434 # Modules
1435
1436 ifdef CONFIG_MODULES
1437
1438 # By default, build modules as well
1439
1440 all: modules
1441
1442 # When we're building modules with modversions, we need to consider
1443 # the built-in objects during the descend as well, in order to
1444 # make sure the checksums are up to date before we record them.
1445 ifdef CONFIG_MODVERSIONS
1446   KBUILD_BUILTIN := 1
1447 endif
1448
1449 # Build modules
1450 #
1451
1452 # *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFO_BTF_MODULES
1453 # is an exception.
1454 ifdef CONFIG_DEBUG_INFO_BTF_MODULES
1455 KBUILD_BUILTIN := 1
1456 modules: vmlinux
1457 endif
1458
1459 modules: modules_prepare
1460
1461 # Target to prepare building external modules
1462 modules_prepare: prepare
1463         $(Q)$(MAKE) $(build)=scripts scripts/module.lds
1464
1465 endif # CONFIG_MODULES
1466
1467 ###
1468 # Cleaning is done on three levels.
1469 # make clean     Delete most generated files
1470 #                Leave enough to build external modules
1471 # make mrproper  Delete the current configuration, and all generated files
1472 # make distclean Remove editor backup files, patch leftover files and the like
1473
1474 # Directories & files removed with 'make clean'
1475 CLEAN_FILES += vmlinux.symvers modules-only.symvers \
1476                modules.builtin modules.builtin.modinfo modules.nsdeps \
1477                compile_commands.json .thinlto-cache rust/test rust/doc \
1478                rust-project.json .vmlinux.objs .vmlinux.export.c
1479
1480 # Directories & files removed with 'make mrproper'
1481 MRPROPER_FILES += include/config include/generated          \
1482                   arch/$(SRCARCH)/include/generated .objdiff \
1483                   debian snap tar-install \
1484                   .config .config.old .version \
1485                   Module.symvers \
1486                   certs/signing_key.pem \
1487                   certs/x509.genkey \
1488                   vmlinux-gdb.py \
1489                   kernel.spec rpmbuild \
1490                   rust/libmacros.so
1491
1492 # clean - Delete most, but leave enough to build external modules
1493 #
1494 clean: rm-files := $(CLEAN_FILES)
1495
1496 PHONY += archclean vmlinuxclean
1497
1498 vmlinuxclean:
1499         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1500         $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1501
1502 clean: archclean vmlinuxclean resolve_btfids_clean
1503
1504 # mrproper - Delete all generated files, including .config
1505 #
1506 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1507 mrproper-dirs      := $(addprefix _mrproper_,scripts)
1508
1509 PHONY += $(mrproper-dirs) mrproper
1510 $(mrproper-dirs):
1511         $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1512
1513 mrproper: clean $(mrproper-dirs)
1514         $(call cmd,rmfiles)
1515         @find . $(RCS_FIND_IGNORE) \
1516                 \( -name '*.rmeta' \) \
1517                 -type f -print | xargs rm -f
1518
1519 # distclean
1520 #
1521 PHONY += distclean
1522
1523 distclean: mrproper
1524         @find . $(RCS_FIND_IGNORE) \
1525                 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1526                 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1527                 -o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1528                 -o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1529                 -type f -print | xargs rm -f
1530
1531
1532 # Packaging of the kernel to various formats
1533 # ---------------------------------------------------------------------------
1534
1535 %src-pkg: FORCE
1536         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1537 %pkg: include/config/kernel.release FORCE
1538         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1539
1540 # Brief documentation of the typical targets used
1541 # ---------------------------------------------------------------------------
1542
1543 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1544 boards := $(sort $(notdir $(boards)))
1545 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1546 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1547
1548 PHONY += help
1549 help:
1550         @echo  'Cleaning targets:'
1551         @echo  '  clean           - Remove most generated files but keep the config and'
1552         @echo  '                    enough build support to build external modules'
1553         @echo  '  mrproper        - Remove all generated files + config + various backup files'
1554         @echo  '  distclean       - mrproper + remove editor backup and patch files'
1555         @echo  ''
1556         @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1557         @echo  ''
1558         @echo  'Other generic targets:'
1559         @echo  '  all             - Build all targets marked with [*]'
1560         @echo  '* vmlinux         - Build the bare kernel'
1561         @echo  '* modules         - Build all modules'
1562         @echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1563         @echo  '  dir/            - Build all files in dir and below'
1564         @echo  '  dir/file.[ois]  - Build specified target only'
1565         @echo  '  dir/file.ll     - Build the LLVM assembly file'
1566         @echo  '                    (requires compiler support for LLVM assembly generation)'
1567         @echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1568         @echo  '                    (requires a recent binutils and recent build (System.map))'
1569         @echo  '  dir/file.ko     - Build module including final link'
1570         @echo  '  modules_prepare - Set up for building external modules'
1571         @echo  '  tags/TAGS       - Generate tags file for editors'
1572         @echo  '  cscope          - Generate cscope index'
1573         @echo  '  gtags           - Generate GNU GLOBAL index'
1574         @echo  '  kernelrelease   - Output the release version string (use with make -s)'
1575         @echo  '  kernelversion   - Output the version stored in Makefile (use with make -s)'
1576         @echo  '  image_name      - Output the image name (use with make -s)'
1577         @echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1578          echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1579          echo  ''
1580         @echo  'Static analysers:'
1581         @echo  '  checkstack      - Generate a list of stack hogs'
1582         @echo  '  versioncheck    - Sanity check on version.h usage'
1583         @echo  '  includecheck    - Check for duplicate included header files'
1584         @echo  '  export_report   - List the usages of all exported symbols'
1585         @echo  '  headerdep       - Detect inclusion cycles in headers'
1586         @echo  '  coccicheck      - Check with Coccinelle'
1587         @echo  '  clang-analyzer  - Check with clang static analyzer'
1588         @echo  '  clang-tidy      - Check with clang-tidy'
1589         @echo  ''
1590         @echo  'Tools:'
1591         @echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1592         @echo  ''
1593         @echo  'Kernel selftest:'
1594         @echo  '  kselftest         - Build and run kernel selftest'
1595         @echo  '                      Build, install, and boot kernel before'
1596         @echo  '                      running kselftest on it'
1597         @echo  '                      Run as root for full coverage'
1598         @echo  '  kselftest-all     - Build kernel selftest'
1599         @echo  '  kselftest-install - Build and install kernel selftest'
1600         @echo  '  kselftest-clean   - Remove all generated kselftest files'
1601         @echo  '  kselftest-merge   - Merge all the config dependencies of'
1602         @echo  '                      kselftest to existing .config.'
1603         @echo  ''
1604         @echo  'Rust targets:'
1605         @echo  '  rustavailable   - Checks whether the Rust toolchain is'
1606         @echo  '                    available and, if not, explains why.'
1607         @echo  '  rustfmt         - Reformat all the Rust code in the kernel'
1608         @echo  '  rustfmtcheck    - Checks if all the Rust code in the kernel'
1609         @echo  '                    is formatted, printing a diff otherwise.'
1610         @echo  '  rustdoc         - Generate Rust documentation'
1611         @echo  '                    (requires kernel .config)'
1612         @echo  '  rusttest        - Runs the Rust tests'
1613         @echo  '                    (requires kernel .config; downloads external repos)'
1614         @echo  '  rust-analyzer   - Generate rust-project.json rust-analyzer support file'
1615         @echo  '                    (requires kernel .config)'
1616         @echo  '  dir/file.[os]   - Build specified target only'
1617         @echo  '  dir/file.rsi    - Build macro expanded source, similar to C preprocessing.'
1618         @echo  '                    Run with RUSTFMT=n to skip reformatting if needed.'
1619         @echo  '                    The output is not intended to be compilable.'
1620         @echo  '  dir/file.ll     - Build the LLVM assembly file'
1621         @echo  ''
1622         @$(if $(dtstree), \
1623                 echo 'Devicetree:'; \
1624                 echo '* dtbs             - Build device tree blobs for enabled boards'; \
1625                 echo '  dtbs_install     - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1626                 echo '  dt_binding_check - Validate device tree binding documents'; \
1627                 echo '  dtbs_check       - Validate device tree source files';\
1628                 echo '')
1629
1630         @echo 'Userspace tools targets:'
1631         @echo '  use "make tools/help"'
1632         @echo '  or  "cd tools; make help"'
1633         @echo  ''
1634         @echo  'Kernel packaging:'
1635         @$(MAKE) -f $(srctree)/scripts/Makefile.package help
1636         @echo  ''
1637         @echo  'Documentation targets:'
1638         @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1639         @echo  ''
1640         @echo  'Architecture specific targets ($(SRCARCH)):'
1641         @$(or $(archhelp),\
1642                 echo '  No architecture specific help defined for $(SRCARCH)')
1643         @echo  ''
1644         @$(if $(boards), \
1645                 $(foreach b, $(boards), \
1646                 printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1647                 echo '')
1648         @$(if $(board-dirs), \
1649                 $(foreach b, $(board-dirs), \
1650                 printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1651                 printf "  %-16s - Show all of the above\\n" help-boards; \
1652                 echo '')
1653
1654         @echo  '  make V=n   [targets] 1: verbose build'
1655         @echo  '                       2: give reason for rebuild of target'
1656         @echo  '                       V=1 and V=2 can be combined with V=12'
1657         @echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1658         @echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1659         @echo  '                       (sparse by default)'
1660         @echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1661         @echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1662         @echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
1663         @echo  '                1: warnings which may be relevant and do not occur too often'
1664         @echo  '                2: warnings which occur quite often but may still be relevant'
1665         @echo  '                3: more obscure warnings, can most likely be ignored'
1666         @echo  '                e: warnings are being treated as errors'
1667         @echo  '                Multiple levels can be combined with W=12 or W=123'
1668         @$(if $(dtstree), \
1669                 echo '  make CHECK_DTBS=1 [targets] Check all generated dtb files against schema'; \
1670                 echo '         This can be applied both to "dtbs" and to individual "foo.dtb" targets' ; \
1671                 )
1672         @echo  ''
1673         @echo  'Execute "make" or "make all" to build all targets marked with [*] '
1674         @echo  'For further info see the ./README file'
1675
1676
1677 help-board-dirs := $(addprefix help-,$(board-dirs))
1678
1679 help-boards: $(help-board-dirs)
1680
1681 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1682
1683 $(help-board-dirs): help-%:
1684         @echo  'Architecture specific targets ($(SRCARCH) $*):'
1685         @$(if $(boards-per-dir), \
1686                 $(foreach b, $(boards-per-dir), \
1687                 printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1688                 echo '')
1689
1690
1691 # Documentation targets
1692 # ---------------------------------------------------------------------------
1693 DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1694                linkcheckdocs dochelp refcheckdocs texinfodocs infodocs
1695 PHONY += $(DOC_TARGETS)
1696 $(DOC_TARGETS):
1697         $(Q)$(MAKE) $(build)=Documentation $@
1698
1699
1700 # Rust targets
1701 # ---------------------------------------------------------------------------
1702
1703 # "Is Rust available?" target
1704 PHONY += rustavailable
1705 rustavailable:
1706         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh && echo "Rust is available!"
1707
1708 # Documentation target
1709 #
1710 # Using the singular to avoid running afoul of `no-dot-config-targets`.
1711 PHONY += rustdoc
1712 rustdoc: prepare
1713         $(Q)$(MAKE) $(build)=rust $@
1714
1715 # Testing target
1716 PHONY += rusttest
1717 rusttest: prepare
1718         $(Q)$(MAKE) $(build)=rust $@
1719
1720 # Formatting targets
1721 PHONY += rustfmt rustfmtcheck
1722
1723 # We skip `rust/alloc` since we want to minimize the diff w.r.t. upstream.
1724 #
1725 # We match using absolute paths since `find` does not resolve them
1726 # when matching, which is a problem when e.g. `srctree` is `..`.
1727 # We `grep` afterwards in order to remove the directory entry itself.
1728 rustfmt:
1729         $(Q)find $(abs_srctree) -type f -name '*.rs' \
1730                 -o -path $(abs_srctree)/rust/alloc -prune \
1731                 -o -path $(abs_objtree)/rust/test -prune \
1732                 | grep -Fv $(abs_srctree)/rust/alloc \
1733                 | grep -Fv $(abs_objtree)/rust/test \
1734                 | grep -Fv generated \
1735                 | xargs $(RUSTFMT) $(rustfmt_flags)
1736
1737 rustfmtcheck: rustfmt_flags = --check
1738 rustfmtcheck: rustfmt
1739
1740 # Misc
1741 # ---------------------------------------------------------------------------
1742
1743 PHONY += misc-check
1744 misc-check:
1745         $(Q)$(srctree)/scripts/misc-check
1746
1747 all: misc-check
1748
1749 PHONY += scripts_gdb
1750 scripts_gdb: prepare0
1751         $(Q)$(MAKE) $(build)=scripts/gdb
1752         $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1753
1754 ifdef CONFIG_GDB_SCRIPTS
1755 all: scripts_gdb
1756 endif
1757
1758 else # KBUILD_EXTMOD
1759
1760 filechk_kernel.release = echo $(KERNELRELEASE)
1761
1762 ###
1763 # External module support.
1764 # When building external modules the kernel used as basis is considered
1765 # read-only, and no consistency checks are made and the make
1766 # system is not used on the basis kernel. If updates are required
1767 # in the basis kernel ordinary make commands (without M=...) must be used.
1768
1769 # We are always building only modules.
1770 KBUILD_BUILTIN :=
1771 KBUILD_MODULES := 1
1772
1773 build-dir := $(KBUILD_EXTMOD)
1774
1775 compile_commands.json: $(extmod_prefix)compile_commands.json
1776 PHONY += compile_commands.json
1777
1778 clean-dirs := $(KBUILD_EXTMOD)
1779 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1780         $(KBUILD_EXTMOD)/compile_commands.json $(KBUILD_EXTMOD)/.thinlto-cache
1781
1782 PHONY += prepare
1783 # now expand this into a simple variable to reduce the cost of shell evaluations
1784 prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT)
1785 prepare:
1786         @if [ "$(CC_VERSION_TEXT)" != "$(CONFIG_CC_VERSION_TEXT)" ]; then \
1787                 echo >&2 "warning: the compiler differs from the one used to build the kernel"; \
1788                 echo >&2 "  The kernel was built by: $(CONFIG_CC_VERSION_TEXT)"; \
1789                 echo >&2 "  You are using:           $(CC_VERSION_TEXT)"; \
1790         fi
1791
1792 PHONY += help
1793 help:
1794         @echo  '  Building external modules.'
1795         @echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1796         @echo  ''
1797         @echo  '  modules         - default target, build the module(s)'
1798         @echo  '  modules_install - install the module'
1799         @echo  '  clean           - remove generated files in module directory only'
1800         @echo  '  rust-analyzer   - generate rust-project.json rust-analyzer support file'
1801         @echo  ''
1802
1803 ifndef CONFIG_MODULES
1804 modules modules_install: __external_modules_error
1805 __external_modules_error:
1806         @echo >&2 '***'
1807         @echo >&2 '*** The present kernel disabled CONFIG_MODULES.'
1808         @echo >&2 '*** You cannot build or install external modules.'
1809         @echo >&2 '***'
1810         @false
1811 endif
1812
1813 endif # KBUILD_EXTMOD
1814
1815 # ---------------------------------------------------------------------------
1816 # Modules
1817
1818 PHONY += modules modules_install modules_sign modules_prepare
1819
1820 modules_install:
1821         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst \
1822         sign-only=$(if $(filter modules_install,$(MAKECMDGOALS)),,y)
1823
1824 ifeq ($(CONFIG_MODULE_SIG),y)
1825 # modules_sign is a subset of modules_install.
1826 # 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1827 modules_sign: modules_install
1828         @:
1829 else
1830 modules_sign:
1831         @echo >&2 '***'
1832         @echo >&2 '*** CONFIG_MODULE_SIG is disabled. You cannot sign modules.'
1833         @echo >&2 '***'
1834         @false
1835 endif
1836
1837 ifdef CONFIG_MODULES
1838
1839 $(MODORDER): $(build-dir)
1840         @:
1841
1842 # KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
1843 # This is solely useful to speed up test compiles.
1844 modules: modpost
1845 ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1846         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1847 endif
1848
1849 PHONY += modules_check
1850 modules_check: $(MODORDER)
1851         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1852
1853 else # CONFIG_MODULES
1854
1855 modules:
1856         @:
1857
1858 KBUILD_MODULES :=
1859
1860 endif # CONFIG_MODULES
1861
1862 PHONY += modpost
1863 modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \
1864          $(if $(KBUILD_MODULES), modules_check)
1865         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1866
1867 # Single targets
1868 # ---------------------------------------------------------------------------
1869 # To build individual files in subdirectories, you can do like this:
1870 #
1871 #   make foo/bar/baz.s
1872 #
1873 # The supported suffixes for single-target are listed in 'single-targets'
1874 #
1875 # To build only under specific subdirectories, you can do like this:
1876 #
1877 #   make foo/bar/baz/
1878
1879 ifdef single-build
1880
1881 # .ko is special because modpost is needed
1882 single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1883 single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \
1884                 $(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko)))
1885
1886 $(single-ko): single_modules
1887         @:
1888 $(single-no-ko): $(build-dir)
1889         @:
1890
1891 # Remove MODORDER when done because it is not the real one.
1892 PHONY += single_modules
1893 single_modules: $(single-no-ko) modules_prepare
1894         $(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$(m:%.ko=%.o);) } > $(MODORDER)
1895         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1896 ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1897         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1898 endif
1899         $(Q)rm -f $(MODORDER)
1900
1901 single-goals := $(addprefix $(build-dir)/, $(single-no-ko))
1902
1903 KBUILD_MODULES := 1
1904
1905 endif
1906
1907 # Preset locale variables to speed up the build process. Limit locale
1908 # tweaks to this spot to avoid wrong language settings when running
1909 # make menuconfig etc.
1910 # Error messages still appears in the original language
1911 PHONY += $(build-dir)
1912 $(build-dir): prepare
1913         $(Q)$(MAKE) $(build)=$@ need-builtin=1 need-modorder=1 $(single-goals)
1914
1915 clean-dirs := $(addprefix _clean_, $(clean-dirs))
1916 PHONY += $(clean-dirs) clean
1917 $(clean-dirs):
1918         $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1919
1920 clean: $(clean-dirs)
1921         $(call cmd,rmfiles)
1922         @find $(or $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1923                 \( -name '*.[aios]' -o -name '*.rsi' -o -name '*.ko' -o -name '.*.cmd' \
1924                 -o -name '*.ko.*' \
1925                 -o -name '*.dtb' -o -name '*.dtbo' \
1926                 -o -name '*.dtb.S' -o -name '*.dtbo.S' \
1927                 -o -name '*.dt.yaml' \
1928                 -o -name '*.dwo' -o -name '*.lst' \
1929                 -o -name '*.su' -o -name '*.mod' \
1930                 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1931                 -o -name '*.lex.c' -o -name '*.tab.[ch]' \
1932                 -o -name '*.asn1.[ch]' \
1933                 -o -name '*.symtypes' -o -name 'modules.order' \
1934                 -o -name '*.c.[012]*.*' \
1935                 -o -name '*.ll' \
1936                 -o -name '*.gcno' \
1937                 -o -name '*.*.symversions' \) -type f -print \
1938                 -o -name '.tmp_*' -print \
1939                 | xargs rm -rf
1940
1941 # Generate tags for editors
1942 # ---------------------------------------------------------------------------
1943 quiet_cmd_tags = GEN     $@
1944       cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1945
1946 tags TAGS cscope gtags: FORCE
1947         $(call cmd,tags)
1948
1949 # IDE support targets
1950 PHONY += rust-analyzer
1951 rust-analyzer:
1952         $(Q)$(MAKE) $(build)=rust $@
1953
1954 # Script to generate missing namespace dependencies
1955 # ---------------------------------------------------------------------------
1956
1957 PHONY += nsdeps
1958 nsdeps: export KBUILD_NSDEPS=1
1959 nsdeps: modules
1960         $(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1961
1962 # Clang Tooling
1963 # ---------------------------------------------------------------------------
1964
1965 quiet_cmd_gen_compile_commands = GEN     $@
1966       cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
1967
1968 $(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
1969         $(if $(KBUILD_EXTMOD),, vmlinux.a $(KBUILD_VMLINUX_LIBS)) \
1970         $(if $(CONFIG_MODULES), $(MODORDER)) FORCE
1971         $(call if_changed,gen_compile_commands)
1972
1973 targets += $(extmod_prefix)compile_commands.json
1974
1975 PHONY += clang-tidy clang-analyzer
1976
1977 ifdef CONFIG_CC_IS_CLANG
1978 quiet_cmd_clang_tools = CHECK   $<
1979       cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
1980
1981 clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
1982         $(call cmd,clang_tools)
1983 else
1984 clang-tidy clang-analyzer:
1985         @echo "$@ requires CC=clang" >&2
1986         @false
1987 endif
1988
1989 # Scripts to check various things for consistency
1990 # ---------------------------------------------------------------------------
1991
1992 PHONY += includecheck versioncheck coccicheck export_report
1993
1994 includecheck:
1995         find $(srctree)/* $(RCS_FIND_IGNORE) \
1996                 -name '*.[hcS]' -type f -print | sort \
1997                 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1998
1999 versioncheck:
2000         find $(srctree)/* $(RCS_FIND_IGNORE) \
2001                 -name '*.[hcS]' -type f -print | sort \
2002                 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
2003
2004 coccicheck:
2005         $(Q)$(BASH) $(srctree)/scripts/$@
2006
2007 export_report:
2008         $(PERL) $(srctree)/scripts/export_report.pl
2009
2010 PHONY += checkstack kernelrelease kernelversion image_name
2011
2012 # UML needs a little special treatment here.  It wants to use the host
2013 # toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
2014 # else wants $(ARCH), including people doing cross-builds, which means
2015 # that $(SUBARCH) doesn't work here.
2016 ifeq ($(ARCH), um)
2017 CHECKSTACK_ARCH := $(SUBARCH)
2018 else
2019 CHECKSTACK_ARCH := $(ARCH)
2020 endif
2021 checkstack:
2022         $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
2023         $(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
2024
2025 kernelrelease:
2026         @$(filechk_kernel.release)
2027
2028 kernelversion:
2029         @echo $(KERNELVERSION)
2030
2031 image_name:
2032         @echo $(KBUILD_IMAGE)
2033
2034 PHONY += run-command
2035 run-command:
2036         $(Q)$(KBUILD_RUN_COMMAND)
2037
2038 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
2039       cmd_rmfiles = rm -rf $(rm-files)
2040
2041 # read saved command lines for existing targets
2042 existing-targets := $(wildcard $(sort $(targets)))
2043
2044 -include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
2045
2046 endif # config-build
2047 endif # mixed-build
2048 endif # need-sub-make
2049
2050 PHONY += FORCE
2051 FORCE:
2052
2053 # Declare the contents of the PHONY variable as phony.  We keep that
2054 # information in a variable so we can use it in if_changed and friends.
2055 .PHONY: $(PHONY)