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   1# SPDX-License-Identifier: GPL-2.0
   2VERSION = 6
   3PATCHLEVEL = 9
   4SUBLEVEL = 4
   5EXTRAVERSION =
   6NAME = 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
  14ifeq ($(filter undefine,$(.FEATURES)),)
  15$(error GNU Make >= 3.82 is required. Your Make version is $(MAKE_VERSION))
  16endif
  17
  18$(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
  22PHONY := __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
  41this-makefile := $(lastword $(MAKEFILE_LIST))
  42abs_srctree := $(realpath $(dir $(this-makefile)))
  43abs_objtree := $(CURDIR)
  44
  45ifneq ($(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)
  49MAKEFLAGS += -rR
  50
  51# Avoid funny character set dependencies
  52unexport LC_ALL
  53LC_COLLATE=C
  54LC_NUMERIC=C
  55export LC_COLLATE LC_NUMERIC
  56
  57# Avoid interference with shell env settings
  58unexport 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) $(build)=scripts/basic
  75#
  76# If KBUILD_VERBOSE contains 1, the whole command is echoed.
  77# If KBUILD_VERBOSE contains 2, the reason for rebuilding is printed.
  78#
  79# To put more focus on warnings, be less verbose as default
  80# Use 'make V=1' to see the full commands
  81
  82ifeq ("$(origin V)", "command line")
  83  KBUILD_VERBOSE = $(V)
  84endif
  85
  86quiet = quiet_
  87Q = @
  88
  89ifneq ($(findstring 1, $(KBUILD_VERBOSE)),)
  90  quiet =
  91  Q =
  92endif
  93
  94# If the user is running make -s (silent mode), suppress echoing of
  95# commands
  96# make-4.0 (and later) keep single letter options in the 1st word of MAKEFLAGS.
  97
  98ifeq ($(filter 3.%,$(MAKE_VERSION)),)
  99short-opts := $(firstword -$(MAKEFLAGS))
 100else
 101short-opts := $(filter-out --%,$(MAKEFLAGS))
 102endif
 103
 104ifneq ($(findstring s,$(short-opts)),)
 105quiet=silent_
 106override KBUILD_VERBOSE :=
 107endif
 108
 109export 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
 121ifeq ("$(origin C)", "command line")
 122  KBUILD_CHECKSRC = $(C)
 123endif
 124ifndef KBUILD_CHECKSRC
 125  KBUILD_CHECKSRC = 0
 126endif
 127
 128export KBUILD_CHECKSRC
 129
 130# Enable "clippy" (a linter) as part of the Rust compilation.
 131#
 132# Use 'make CLIPPY=1' to enable it.
 133ifeq ("$(origin CLIPPY)", "command line")
 134  KBUILD_CLIPPY := $(CLIPPY)
 135endif
 136
 137export KBUILD_CLIPPY
 138
 139# Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
 140# directory of external module to build. Setting M= takes precedence.
 141ifeq ("$(origin M)", "command line")
 142  KBUILD_EXTMOD := $(M)
 143endif
 144
 145$(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
 152ifneq ($(filter %/, $(KBUILD_EXTMOD)),)
 153KBUILD_EXTMOD := $(shell dirname $(KBUILD_EXTMOD).)
 154endif
 155
 156export KBUILD_EXTMOD
 157
 158# backward compatibility
 159KBUILD_EXTRA_WARN ?= $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)
 160
 161ifeq ("$(origin W)", "command line")
 162  KBUILD_EXTRA_WARN := $(W)
 163endif
 164
 165export KBUILD_EXTRA_WARN
 166
 167# Kbuild will save output files in the current working directory.
 168# This does not need to match to the root of the kernel source tree.
 169#
 170# For example, you can do this:
 171#
 172#  cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
 173#
 174# If you want to save output files in a different location, there are
 175# two syntaxes to specify it.
 176#
 177# 1) O=
 178# Use "make O=dir/to/store/output/files/"
 179#
 180# 2) Set KBUILD_OUTPUT
 181# Set the environment variable KBUILD_OUTPUT to point to the output directory.
 182# export KBUILD_OUTPUT=dir/to/store/output/files/; make
 183#
 184# The O= assignment takes precedence over the KBUILD_OUTPUT environment
 185# variable.
 186
 187# Do we want to change the working directory?
 188ifeq ("$(origin O)", "command line")
 189  KBUILD_OUTPUT := $(O)
 190endif
 191
 192ifneq ($(KBUILD_OUTPUT),)
 193# $(realpath ...) gets empty if the path does not exist. Run 'mkdir -p' first.
 194$(shell mkdir -p "$(KBUILD_OUTPUT)")
 195# $(realpath ...) resolves symlinks
 196abs_objtree := $(realpath $(KBUILD_OUTPUT))
 197$(if $(abs_objtree),,$(error failed to create output directory "$(KBUILD_OUTPUT)"))
 198endif # ifneq ($(KBUILD_OUTPUT),)
 199
 200ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
 201$(error source directory cannot contain spaces or colons)
 202endif
 203
 204ifneq ($(filter 3.%,$(MAKE_VERSION)),)
 205# 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
 206# We need to invoke sub-make to avoid implicit rules in the top Makefile.
 207need-sub-make := 1
 208# Cancel implicit rules for this Makefile.
 209$(this-makefile): ;
 210endif
 211
 212export sub_make_done := 1
 213
 214endif # sub_make_done
 215
 216ifeq ($(abs_objtree),$(CURDIR))
 217# Suppress "Entering directory ..." if we are at the final work directory.
 218no-print-directory := --no-print-directory
 219else
 220# Recursion to show "Entering directory ..."
 221need-sub-make := 1
 222endif
 223
 224ifeq ($(filter --no-print-directory, $(MAKEFLAGS)),)
 225# If --no-print-directory is unset, recurse once again to set it.
 226# You may end up recursing into __sub-make twice. This is needed due to the
 227# behavior change in GNU Make 4.4.1.
 228need-sub-make := 1
 229endif
 230
 231ifeq ($(need-sub-make),1)
 232
 233PHONY += $(MAKECMDGOALS) __sub-make
 234
 235$(filter-out $(this-makefile), $(MAKECMDGOALS)) __all: __sub-make
 236	@:
 237
 238# Invoke a second make in the output directory, passing relevant variables
 239__sub-make:
 240	$(Q)$(MAKE) $(no-print-directory) -C $(abs_objtree) \
 241	-f $(abs_srctree)/Makefile $(MAKECMDGOALS)
 242
 243else # need-sub-make
 244
 245# We process the rest of the Makefile if this is the final invocation of make
 246
 247ifeq ($(abs_srctree),$(abs_objtree))
 248        # building in the source tree
 249        srctree := .
 250	building_out_of_srctree :=
 251else
 252        ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
 253                # building in a subdirectory of the source tree
 254                srctree := ..
 255        else
 256                srctree := $(abs_srctree)
 257        endif
 258	building_out_of_srctree := 1
 259endif
 260
 261ifneq ($(KBUILD_ABS_SRCTREE),)
 262srctree := $(abs_srctree)
 263endif
 264
 265objtree		:= .
 266VPATH		:= $(srctree)
 267
 268export building_out_of_srctree srctree objtree VPATH
 269
 270# To make sure we do not include .config for any of the *config targets
 271# catch them early, and hand them over to scripts/kconfig/Makefile
 272# It is allowed to specify more targets when calling make, including
 273# mixing *config targets and build targets.
 274# For example 'make oldconfig all'.
 275# Detect when mixed targets is specified, and make a second invocation
 276# of make so .config is not included in this case either (for *config).
 277
 278version_h := include/generated/uapi/linux/version.h
 279
 280clean-targets := %clean mrproper cleandocs
 281no-dot-config-targets := $(clean-targets) \
 282			 cscope gtags TAGS tags help% %docs check% coccicheck \
 283			 $(version_h) headers headers_% archheaders archscripts \
 284			 %asm-generic kernelversion %src-pkg dt_binding_check \
 285			 outputmakefile rustavailable rustfmt rustfmtcheck
 286no-sync-config-targets := $(no-dot-config-targets) %install modules_sign kernelrelease \
 287			  image_name
 288single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.rsi %.s %.symtypes %/
 289
 290config-build	:=
 291mixed-build	:=
 292need-config	:= 1
 293may-sync-config	:= 1
 294single-build	:=
 295
 296ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
 297    ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
 298        need-config :=
 299    endif
 300endif
 301
 302ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
 303    ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
 304        may-sync-config :=
 305    endif
 306endif
 307
 308need-compiler := $(may-sync-config)
 309
 310ifneq ($(KBUILD_EXTMOD),)
 311    may-sync-config :=
 312endif
 313
 314ifeq ($(KBUILD_EXTMOD),)
 315    ifneq ($(filter %config,$(MAKECMDGOALS)),)
 316        config-build := 1
 317        ifneq ($(words $(MAKECMDGOALS)),1)
 318            mixed-build := 1
 319        endif
 320    endif
 321endif
 322
 323# We cannot build single targets and the others at the same time
 324ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
 325    single-build := 1
 326    ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
 327        mixed-build := 1
 328    endif
 329endif
 330
 331# For "make -j clean all", "make -j mrproper defconfig all", etc.
 332ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
 333    ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
 334        mixed-build := 1
 335    endif
 336endif
 337
 338# install and modules_install need also be processed one by one
 339ifneq ($(filter install,$(MAKECMDGOALS)),)
 340    ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
 341        mixed-build := 1
 342    endif
 343endif
 344
 345ifdef mixed-build
 346# ===========================================================================
 347# We're called with mixed targets (*config and build targets).
 348# Handle them one by one.
 349
 350PHONY += $(MAKECMDGOALS) __build_one_by_one
 351
 352$(MAKECMDGOALS): __build_one_by_one
 353	@:
 354
 355__build_one_by_one:
 356	$(Q)set -e; \
 357	for i in $(MAKECMDGOALS); do \
 358		$(MAKE) -f $(srctree)/Makefile $$i; \
 359	done
 360
 361else # !mixed-build
 362
 363include $(srctree)/scripts/Kbuild.include
 364
 365# Read KERNELRELEASE from include/config/kernel.release (if it exists)
 366KERNELRELEASE = $(call read-file, include/config/kernel.release)
 367KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
 368export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
 369
 370include $(srctree)/scripts/subarch.include
 371
 372# Cross compiling and selecting different set of gcc/bin-utils
 373# ---------------------------------------------------------------------------
 374#
 375# When performing cross compilation for other architectures ARCH shall be set
 376# to the target architecture. (See arch/* for the possibilities).
 377# ARCH can be set during invocation of make:
 378# make ARCH=arm64
 379# Another way is to have ARCH set in the environment.
 380# The default ARCH is the host where make is executed.
 381
 382# CROSS_COMPILE specify the prefix used for all executables used
 383# during compilation. Only gcc and related bin-utils executables
 384# are prefixed with $(CROSS_COMPILE).
 385# CROSS_COMPILE can be set on the command line
 386# make CROSS_COMPILE=aarch64-linux-gnu-
 387# Alternatively CROSS_COMPILE can be set in the environment.
 388# Default value for CROSS_COMPILE is not to prefix executables
 389# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
 390ARCH		?= $(SUBARCH)
 391
 392# Architecture as present in compile.h
 393UTS_MACHINE 	:= $(ARCH)
 394SRCARCH 	:= $(ARCH)
 395
 396# Additional ARCH settings for x86
 397ifeq ($(ARCH),i386)
 398        SRCARCH := x86
 399endif
 400ifeq ($(ARCH),x86_64)
 401        SRCARCH := x86
 402endif
 403
 404# Additional ARCH settings for sparc
 405ifeq ($(ARCH),sparc32)
 406       SRCARCH := sparc
 407endif
 408ifeq ($(ARCH),sparc64)
 409       SRCARCH := sparc
 410endif
 411
 412# Additional ARCH settings for parisc
 413ifeq ($(ARCH),parisc64)
 414       SRCARCH := parisc
 415endif
 416
 417export cross_compiling :=
 418ifneq ($(SRCARCH),$(SUBARCH))
 419cross_compiling := 1
 420endif
 421
 422KCONFIG_CONFIG	?= .config
 423export KCONFIG_CONFIG
 424
 425# SHELL used by kbuild
 426CONFIG_SHELL := sh
 427
 428HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
 429HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
 430HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
 431
 432ifneq ($(LLVM),)
 433ifneq ($(filter %/,$(LLVM)),)
 434LLVM_PREFIX := $(LLVM)
 435else ifneq ($(filter -%,$(LLVM)),)
 436LLVM_SUFFIX := $(LLVM)
 437endif
 438
 439HOSTCC	= $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
 440HOSTCXX	= $(LLVM_PREFIX)clang++$(LLVM_SUFFIX)
 441else
 442HOSTCC	= gcc
 443HOSTCXX	= g++
 444endif
 445HOSTRUSTC = rustc
 446HOSTPKG_CONFIG	= pkg-config
 447
 448KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
 449			 -O2 -fomit-frame-pointer -std=gnu11
 450KBUILD_USERCFLAGS  := $(KBUILD_USERHOSTCFLAGS) $(USERCFLAGS)
 451KBUILD_USERLDFLAGS := $(USERLDFLAGS)
 452
 453# These flags apply to all Rust code in the tree, including the kernel and
 454# host programs.
 455export rust_common_flags := --edition=2021 \
 456			    -Zbinary_dep_depinfo=y \
 457			    -Dunsafe_op_in_unsafe_fn -Drust_2018_idioms \
 458			    -Dunreachable_pub -Dnon_ascii_idents \
 459			    -Wmissing_docs \
 460			    -Drustdoc::missing_crate_level_docs \
 461			    -Dclippy::correctness -Dclippy::style \
 462			    -Dclippy::suspicious -Dclippy::complexity \
 463			    -Dclippy::perf \
 464			    -Dclippy::let_unit_value -Dclippy::mut_mut \
 465			    -Dclippy::needless_bitwise_bool \
 466			    -Dclippy::needless_continue \
 467			    -Dclippy::no_mangle_with_rust_abi \
 468			    -Wclippy::dbg_macro
 469
 470KBUILD_HOSTCFLAGS   := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
 471KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
 472KBUILD_HOSTRUSTFLAGS := $(rust_common_flags) -O -Cstrip=debuginfo \
 473			-Zallow-features= $(HOSTRUSTFLAGS)
 474KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
 475KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
 476
 477# Make variables (CC, etc...)
 478CPP		= $(CC) -E
 479ifneq ($(LLVM),)
 480CC		= $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
 481LD		= $(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX)
 482AR		= $(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX)
 483NM		= $(LLVM_PREFIX)llvm-nm$(LLVM_SUFFIX)
 484OBJCOPY		= $(LLVM_PREFIX)llvm-objcopy$(LLVM_SUFFIX)
 485OBJDUMP		= $(LLVM_PREFIX)llvm-objdump$(LLVM_SUFFIX)
 486READELF		= $(LLVM_PREFIX)llvm-readelf$(LLVM_SUFFIX)
 487STRIP		= $(LLVM_PREFIX)llvm-strip$(LLVM_SUFFIX)
 488else
 489CC		= $(CROSS_COMPILE)gcc
 490LD		= $(CROSS_COMPILE)ld
 491AR		= $(CROSS_COMPILE)ar
 492NM		= $(CROSS_COMPILE)nm
 493OBJCOPY		= $(CROSS_COMPILE)objcopy
 494OBJDUMP		= $(CROSS_COMPILE)objdump
 495READELF		= $(CROSS_COMPILE)readelf
 496STRIP		= $(CROSS_COMPILE)strip
 497endif
 498RUSTC		= rustc
 499RUSTDOC		= rustdoc
 500RUSTFMT		= rustfmt
 501CLIPPY_DRIVER	= clippy-driver
 502BINDGEN		= bindgen
 503CARGO		= cargo
 504PAHOLE		= pahole
 505RESOLVE_BTFIDS	= $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
 506LEX		= flex
 507YACC		= bison
 508AWK		= awk
 509INSTALLKERNEL  := installkernel
 510PERL		= perl
 511PYTHON3		= python3
 512CHECK		= sparse
 513BASH		= bash
 514KGZIP		= gzip
 515KBZIP2		= bzip2
 516KLZOP		= lzop
 517LZMA		= lzma
 518LZ4		= lz4c
 519XZ		= xz
 520ZSTD		= zstd
 521
 522CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
 523		  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
 524NOSTDINC_FLAGS :=
 525CFLAGS_MODULE   =
 526RUSTFLAGS_MODULE =
 527AFLAGS_MODULE   =
 528LDFLAGS_MODULE  =
 529CFLAGS_KERNEL	=
 530RUSTFLAGS_KERNEL =
 531AFLAGS_KERNEL	=
 532LDFLAGS_vmlinux =
 533
 534# Use USERINCLUDE when you must reference the UAPI directories only.
 535USERINCLUDE    := \
 536		-I$(srctree)/arch/$(SRCARCH)/include/uapi \
 537		-I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
 538		-I$(srctree)/include/uapi \
 539		-I$(objtree)/include/generated/uapi \
 540                -include $(srctree)/include/linux/compiler-version.h \
 541                -include $(srctree)/include/linux/kconfig.h
 542
 543# Use LINUXINCLUDE when you must reference the include directory.
 544# Needed to be compatible with the O= option
 545LINUXINCLUDE    := \
 546		-I$(srctree)/arch/$(SRCARCH)/include \
 547		-I$(objtree)/arch/$(SRCARCH)/include/generated \
 548		$(if $(building_out_of_srctree),-I$(srctree)/include) \
 549		-I$(objtree)/include \
 550		$(USERINCLUDE)
 551
 552KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
 553
 554KBUILD_CFLAGS :=
 555KBUILD_CFLAGS += -std=gnu11
 556KBUILD_CFLAGS += -fshort-wchar
 557KBUILD_CFLAGS += -funsigned-char
 558KBUILD_CFLAGS += -fno-common
 559KBUILD_CFLAGS += -fno-PIE
 560KBUILD_CFLAGS += -fno-strict-aliasing
 561
 562KBUILD_CPPFLAGS := -D__KERNEL__
 563KBUILD_RUSTFLAGS := $(rust_common_flags) \
 564		    -Cpanic=abort -Cembed-bitcode=n -Clto=n \
 565		    -Cforce-unwind-tables=n -Ccodegen-units=1 \
 566		    -Csymbol-mangling-version=v0 \
 567		    -Crelocation-model=static \
 568		    -Zfunction-sections=n \
 569		    -Dclippy::float_arithmetic
 570
 571KBUILD_AFLAGS_KERNEL :=
 572KBUILD_CFLAGS_KERNEL :=
 573KBUILD_RUSTFLAGS_KERNEL :=
 574KBUILD_AFLAGS_MODULE  := -DMODULE
 575KBUILD_CFLAGS_MODULE  := -DMODULE
 576KBUILD_RUSTFLAGS_MODULE := --cfg MODULE
 577KBUILD_LDFLAGS_MODULE :=
 578KBUILD_LDFLAGS :=
 579CLANG_FLAGS :=
 580
 581ifeq ($(KBUILD_CLIPPY),1)
 582	RUSTC_OR_CLIPPY_QUIET := CLIPPY
 583	RUSTC_OR_CLIPPY = $(CLIPPY_DRIVER)
 584else
 585	RUSTC_OR_CLIPPY_QUIET := RUSTC
 586	RUSTC_OR_CLIPPY = $(RUSTC)
 587endif
 588
 589ifdef RUST_LIB_SRC
 590	export RUST_LIB_SRC
 591endif
 592
 593# Allows the usage of unstable features in stable compilers.
 594export RUSTC_BOOTSTRAP := 1
 595
 596export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG
 597export RUSTC RUSTDOC RUSTFMT RUSTC_OR_CLIPPY_QUIET RUSTC_OR_CLIPPY BINDGEN CARGO
 598export HOSTRUSTC KBUILD_HOSTRUSTFLAGS
 599export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
 600export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
 601export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
 602export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
 603export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS
 604
 605export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
 606export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
 607export KBUILD_RUSTFLAGS RUSTFLAGS_KERNEL RUSTFLAGS_MODULE
 608export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
 609export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_RUSTFLAGS_MODULE KBUILD_LDFLAGS_MODULE
 610export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL KBUILD_RUSTFLAGS_KERNEL
 611
 612# Files to ignore in find ... statements
 613
 614export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
 615			  -name CVS -o -name .pc -o -name .hg -o -name .git \) \
 616			  -prune -o
 617
 618# ===========================================================================
 619# Rules shared between *config targets and build targets
 620
 621# Basic helpers built in scripts/basic
 622PHONY += scripts_basic
 623scripts_basic:
 624	$(Q)$(MAKE) $(build)=scripts/basic
 625
 626PHONY += outputmakefile
 627ifdef building_out_of_srctree
 628# Before starting out-of-tree build, make sure the source tree is clean.
 629# outputmakefile generates a Makefile in the output directory, if using a
 630# separate output directory. This allows convenient use of make in the
 631# output directory.
 632# At the same time when output Makefile generated, generate .gitignore to
 633# ignore whole output directory
 634
 635quiet_cmd_makefile = GEN     Makefile
 636      cmd_makefile = { \
 637	echo "\# Automatically generated by $(srctree)/Makefile: don't edit"; \
 638	echo "include $(srctree)/Makefile"; \
 639	} > Makefile
 640
 641outputmakefile:
 642	@if [ -f $(srctree)/.config -o \
 643		 -d $(srctree)/include/config -o \
 644		 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
 645		echo >&2 "***"; \
 646		echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
 647		echo >&2 "*** in $(abs_srctree)";\
 648		echo >&2 "***"; \
 649		false; \
 650	fi
 651	$(Q)ln -fsn $(srctree) source
 652	$(call cmd,makefile)
 653	$(Q)test -e .gitignore || \
 654	{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
 655endif
 656
 657# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
 658# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
 659# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
 660# and from include/config/auto.conf.cmd to detect the compiler upgrade.
 661CC_VERSION_TEXT = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1))
 662
 663ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
 664include $(srctree)/scripts/Makefile.clang
 665endif
 666
 667# Include this also for config targets because some architectures need
 668# cc-cross-prefix to determine CROSS_COMPILE.
 669ifdef need-compiler
 670include $(srctree)/scripts/Makefile.compiler
 671endif
 672
 673ifdef config-build
 674# ===========================================================================
 675# *config targets only - make sure prerequisites are updated, and descend
 676# in scripts/kconfig to make the *config target
 677
 678# Read arch-specific Makefile to set KBUILD_DEFCONFIG as needed.
 679# KBUILD_DEFCONFIG may point out an alternative default configuration
 680# used for 'make defconfig'
 681include $(srctree)/arch/$(SRCARCH)/Makefile
 682export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
 683
 684config: outputmakefile scripts_basic FORCE
 685	$(Q)$(MAKE) $(build)=scripts/kconfig $@
 686
 687%config: outputmakefile scripts_basic FORCE
 688	$(Q)$(MAKE) $(build)=scripts/kconfig $@
 689
 690else #!config-build
 691# ===========================================================================
 692# Build targets only - this includes vmlinux, arch-specific targets, clean
 693# targets and others. In general all targets except *config targets.
 694
 695# If building an external module we do not care about the all: rule
 696# but instead __all depend on modules
 697PHONY += all
 698ifeq ($(KBUILD_EXTMOD),)
 699__all: all
 700else
 701__all: modules
 702endif
 703
 704targets :=
 705
 706# Decide whether to build built-in, modular, or both.
 707# Normally, just do built-in.
 708
 709KBUILD_MODULES :=
 710KBUILD_BUILTIN := 1
 711
 712# If we have only "make modules", don't compile built-in objects.
 713ifeq ($(MAKECMDGOALS),modules)
 714  KBUILD_BUILTIN :=
 715endif
 716
 717# If we have "make <whatever> modules", compile modules
 718# in addition to whatever we do anyway.
 719# Just "make" or "make all" shall build modules as well
 720
 721ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
 722  KBUILD_MODULES := 1
 723endif
 724
 725ifeq ($(MAKECMDGOALS),)
 726  KBUILD_MODULES := 1
 727endif
 728
 729export KBUILD_MODULES KBUILD_BUILTIN
 730
 731ifdef need-config
 732include include/config/auto.conf
 733endif
 734
 735ifeq ($(KBUILD_EXTMOD),)
 736# Objects we will link into vmlinux / subdirs we need to visit
 737core-y		:=
 738drivers-y	:=
 739libs-y		:= lib
 740endif # KBUILD_EXTMOD
 741
 742# The all: target is the default when no target is given on the
 743# command line.
 744# This allow a user to issue only 'make' to build a kernel including modules
 745# Defaults to vmlinux, but the arch makefile usually adds further targets
 746all: vmlinux
 747
 748CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage
 749ifdef CONFIG_CC_IS_GCC
 750CFLAGS_GCOV	+= -fno-tree-loop-im
 751endif
 752export CFLAGS_GCOV
 753
 754# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
 755ifdef CONFIG_FUNCTION_TRACER
 756  CC_FLAGS_FTRACE := -pg
 757endif
 758
 759include $(srctree)/arch/$(SRCARCH)/Makefile
 760
 761ifdef need-config
 762ifdef may-sync-config
 763# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
 764# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
 765# because some architectures define CROSS_COMPILE there.
 766include include/config/auto.conf.cmd
 767
 768$(KCONFIG_CONFIG):
 769	@echo >&2 '***'
 770	@echo >&2 '*** Configuration file "$@" not found!'
 771	@echo >&2 '***'
 772	@echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
 773	@echo >&2 '*** "make menuconfig" or "make xconfig").'
 774	@echo >&2 '***'
 775	@/bin/false
 776
 777# The actual configuration files used during the build are stored in
 778# include/generated/ and include/config/. Update them if .config is newer than
 779# include/config/auto.conf (which mirrors .config).
 780#
 781# This exploits the 'multi-target pattern rule' trick.
 782# The syncconfig should be executed only once to make all the targets.
 783# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
 784#
 785# Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
 786# so you cannot notice that Kconfig is waiting for the user input.
 787%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h %/generated/rustc_cfg: $(KCONFIG_CONFIG)
 788	$(Q)$(kecho) "  SYNC    $@"
 789	$(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
 790else # !may-sync-config
 791# External modules and some install targets need include/generated/autoconf.h
 792# and include/config/auto.conf but do not care if they are up-to-date.
 793# Use auto.conf to trigger the test
 794PHONY += include/config/auto.conf
 795
 796include/config/auto.conf:
 797	@test -e include/generated/autoconf.h -a -e $@ || (		\
 798	echo >&2;							\
 799	echo >&2 "  ERROR: Kernel configuration is invalid.";		\
 800	echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
 801	echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";	\
 802	echo >&2 ;							\
 803	/bin/false)
 804
 805endif # may-sync-config
 806endif # need-config
 807
 808KBUILD_CFLAGS	+= -fno-delete-null-pointer-checks
 809
 810ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
 811KBUILD_CFLAGS += -O2
 812KBUILD_RUSTFLAGS += -Copt-level=2
 813else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
 814KBUILD_CFLAGS += -Os
 815KBUILD_RUSTFLAGS += -Copt-level=s
 816endif
 817
 818# Always set `debug-assertions` and `overflow-checks` because their default
 819# depends on `opt-level` and `debug-assertions`, respectively.
 820KBUILD_RUSTFLAGS += -Cdebug-assertions=$(if $(CONFIG_RUST_DEBUG_ASSERTIONS),y,n)
 821KBUILD_RUSTFLAGS += -Coverflow-checks=$(if $(CONFIG_RUST_OVERFLOW_CHECKS),y,n)
 822
 823# Tell gcc to never replace conditional load with a non-conditional one
 824ifdef CONFIG_CC_IS_GCC
 825# gcc-10 renamed --param=allow-store-data-races=0 to
 826# -fno-allow-store-data-races.
 827KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
 828KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
 829endif
 830
 831ifdef CONFIG_READABLE_ASM
 832# Disable optimizations that make assembler listings hard to read.
 833# reorder blocks reorders the control in the function
 834# ipa clone creates specialized cloned functions
 835# partial inlining inlines only parts of functions
 836KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
 837endif
 838
 839stackp-flags-y                                    := -fno-stack-protector
 840stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
 841stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
 842
 843KBUILD_CFLAGS += $(stackp-flags-y)
 844
 845KBUILD_RUSTFLAGS-$(CONFIG_WERROR) += -Dwarnings
 846KBUILD_RUSTFLAGS += $(KBUILD_RUSTFLAGS-y)
 847
 848ifdef CONFIG_FRAME_POINTER
 849KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
 850KBUILD_RUSTFLAGS += -Cforce-frame-pointers=y
 851else
 852# Some targets (ARM with Thumb2, for example), can't be built with frame
 853# pointers.  For those, we don't have FUNCTION_TRACER automatically
 854# select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
 855# incompatible with -fomit-frame-pointer with current GCC, so we don't use
 856# -fomit-frame-pointer with FUNCTION_TRACER.
 857# In the Rust target specification, "frame-pointer" is set explicitly
 858# to "may-omit".
 859ifndef CONFIG_FUNCTION_TRACER
 860KBUILD_CFLAGS	+= -fomit-frame-pointer
 861endif
 862endif
 863
 864# Initialize all stack variables with a 0xAA pattern.
 865ifdef CONFIG_INIT_STACK_ALL_PATTERN
 866KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
 867endif
 868
 869# Initialize all stack variables with a zero value.
 870ifdef CONFIG_INIT_STACK_ALL_ZERO
 871KBUILD_CFLAGS	+= -ftrivial-auto-var-init=zero
 872ifdef CONFIG_CC_HAS_AUTO_VAR_INIT_ZERO_ENABLER
 873# https://github.com/llvm/llvm-project/issues/44842
 874CC_AUTO_VAR_INIT_ZERO_ENABLER := -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
 875export CC_AUTO_VAR_INIT_ZERO_ENABLER
 876KBUILD_CFLAGS	+= $(CC_AUTO_VAR_INIT_ZERO_ENABLER)
 877endif
 878endif
 879
 880# While VLAs have been removed, GCC produces unreachable stack probes
 881# for the randomize_kstack_offset feature. Disable it for all compilers.
 882KBUILD_CFLAGS	+= $(call cc-option, -fno-stack-clash-protection)
 883
 884# Clear used registers at func exit (to reduce data lifetime and ROP gadgets).
 885ifdef CONFIG_ZERO_CALL_USED_REGS
 886KBUILD_CFLAGS	+= -fzero-call-used-regs=used-gpr
 887endif
 888
 889ifdef CONFIG_FUNCTION_TRACER
 890ifdef CONFIG_FTRACE_MCOUNT_USE_CC
 891  CC_FLAGS_FTRACE	+= -mrecord-mcount
 892  ifdef CONFIG_HAVE_NOP_MCOUNT
 893    ifeq ($(call cc-option-yn, -mnop-mcount),y)
 894      CC_FLAGS_FTRACE	+= -mnop-mcount
 895      CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
 896    endif
 897  endif
 898endif
 899ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
 900  ifdef CONFIG_HAVE_OBJTOOL_NOP_MCOUNT
 901    CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
 902  endif
 903endif
 904ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
 905  ifdef CONFIG_HAVE_C_RECORDMCOUNT
 906    BUILD_C_RECORDMCOUNT := y
 907    export BUILD_C_RECORDMCOUNT
 908  endif
 909endif
 910ifdef CONFIG_HAVE_FENTRY
 911  # s390-linux-gnu-gcc did not support -mfentry until gcc-9.
 912  ifeq ($(call cc-option-yn, -mfentry),y)
 913    CC_FLAGS_FTRACE	+= -mfentry
 914    CC_FLAGS_USING	+= -DCC_USING_FENTRY
 915  endif
 916endif
 917export CC_FLAGS_FTRACE
 918KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
 919KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
 920endif
 921
 922# We trigger additional mismatches with less inlining
 923ifdef CONFIG_DEBUG_SECTION_MISMATCH
 924KBUILD_CFLAGS += -fno-inline-functions-called-once
 925endif
 926
 927# `rustc`'s `-Zfunction-sections` applies to data too (as of 1.59.0).
 928ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
 929KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
 930KBUILD_RUSTFLAGS_KERNEL += -Zfunction-sections=y
 931LDFLAGS_vmlinux += --gc-sections
 932endif
 933
 934ifdef CONFIG_SHADOW_CALL_STACK
 935ifndef CONFIG_DYNAMIC_SCS
 936CC_FLAGS_SCS	:= -fsanitize=shadow-call-stack
 937KBUILD_CFLAGS	+= $(CC_FLAGS_SCS)
 938endif
 939export CC_FLAGS_SCS
 940endif
 941
 942ifdef CONFIG_LTO_CLANG
 943ifdef CONFIG_LTO_CLANG_THIN
 944CC_FLAGS_LTO	:= -flto=thin -fsplit-lto-unit
 945KBUILD_LDFLAGS	+= --thinlto-cache-dir=$(extmod_prefix).thinlto-cache
 946else
 947CC_FLAGS_LTO	:= -flto
 948endif
 949CC_FLAGS_LTO	+= -fvisibility=hidden
 950
 951# Limit inlining across translation units to reduce binary size
 952KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
 953endif
 954
 955ifdef CONFIG_LTO
 956KBUILD_CFLAGS	+= -fno-lto $(CC_FLAGS_LTO)
 957KBUILD_AFLAGS	+= -fno-lto
 958export CC_FLAGS_LTO
 959endif
 960
 961ifdef CONFIG_CFI_CLANG
 962CC_FLAGS_CFI	:= -fsanitize=kcfi
 963KBUILD_CFLAGS	+= $(CC_FLAGS_CFI)
 964export CC_FLAGS_CFI
 965endif
 966
 967ifneq ($(CONFIG_FUNCTION_ALIGNMENT),0)
 968# Set the minimal function alignment. Use the newer GCC option
 969# -fmin-function-alignment if it is available, or fall back to -falign-funtions.
 970# See also CONFIG_CC_HAS_SANE_FUNCTION_ALIGNMENT.
 971ifdef CONFIG_CC_HAS_MIN_FUNCTION_ALIGNMENT
 972KBUILD_CFLAGS += -fmin-function-alignment=$(CONFIG_FUNCTION_ALIGNMENT)
 973else
 974KBUILD_CFLAGS += -falign-functions=$(CONFIG_FUNCTION_ALIGNMENT)
 975endif
 976endif
 977
 978# arch Makefile may override CC so keep this after arch Makefile is included
 979NOSTDINC_FLAGS += -nostdinc
 980
 981# To gain proper coverage for CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE,
 982# the kernel uses only C99 flexible arrays for dynamically sized trailing
 983# arrays. Enforce this for everything that may examine structure sizes and
 984# perform bounds checking.
 985KBUILD_CFLAGS += $(call cc-option, -fstrict-flex-arrays=3)
 986
 987#Currently, disable -Wstringop-overflow for GCC 11, globally.
 988KBUILD_CFLAGS-$(CONFIG_CC_NO_STRINGOP_OVERFLOW) += $(call cc-option, -Wno-stringop-overflow)
 989KBUILD_CFLAGS-$(CONFIG_CC_STRINGOP_OVERFLOW) += $(call cc-option, -Wstringop-overflow)
 990
 991# disable invalid "can't wrap" optimizations for signed / pointers
 992KBUILD_CFLAGS	+= -fno-strict-overflow
 993
 994# Make sure -fstack-check isn't enabled (like gentoo apparently did)
 995KBUILD_CFLAGS  += -fno-stack-check
 996
 997# conserve stack if available
 998ifdef CONFIG_CC_IS_GCC
 999KBUILD_CFLAGS   += -fconserve-stack
1000endif
1001
1002# change __FILE__ to the relative path from the srctree
1003KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
1004
1005# include additional Makefiles when needed
1006include-y			:= scripts/Makefile.extrawarn
1007include-$(CONFIG_DEBUG_INFO)	+= scripts/Makefile.debug
1008include-$(CONFIG_DEBUG_INFO_BTF)+= scripts/Makefile.btf
1009include-$(CONFIG_KASAN)		+= scripts/Makefile.kasan
1010include-$(CONFIG_KCSAN)		+= scripts/Makefile.kcsan
1011include-$(CONFIG_KMSAN)		+= scripts/Makefile.kmsan
1012include-$(CONFIG_UBSAN)		+= scripts/Makefile.ubsan
1013include-$(CONFIG_KCOV)		+= scripts/Makefile.kcov
1014include-$(CONFIG_RANDSTRUCT)	+= scripts/Makefile.randstruct
1015include-$(CONFIG_GCC_PLUGINS)	+= scripts/Makefile.gcc-plugins
1016
1017include $(addprefix $(srctree)/, $(include-y))
1018
1019# scripts/Makefile.gcc-plugins is intentionally included last.
1020# Do not add $(call cc-option,...) below this line. When you build the kernel
1021# from the clean source tree, the GCC plugins do not exist at this point.
1022
1023# Add user supplied CPPFLAGS, AFLAGS, CFLAGS and RUSTFLAGS as the last assignments
1024KBUILD_CPPFLAGS += $(KCPPFLAGS)
1025KBUILD_AFLAGS   += $(KAFLAGS)
1026KBUILD_CFLAGS   += $(KCFLAGS)
1027KBUILD_RUSTFLAGS += $(KRUSTFLAGS)
1028
1029KBUILD_LDFLAGS_MODULE += --build-id=sha1
1030LDFLAGS_vmlinux += --build-id=sha1
1031
1032KBUILD_LDFLAGS	+= -z noexecstack
1033ifeq ($(CONFIG_LD_IS_BFD),y)
1034KBUILD_LDFLAGS	+= $(call ld-option,--no-warn-rwx-segments)
1035endif
1036
1037ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1038LDFLAGS_vmlinux	+= -X
1039endif
1040
1041ifeq ($(CONFIG_RELR),y)
1042# ld.lld before 15 did not support -z pack-relative-relocs.
1043LDFLAGS_vmlinux	+= $(call ld-option,--pack-dyn-relocs=relr,-z pack-relative-relocs)
1044endif
1045
1046# We never want expected sections to be placed heuristically by the
1047# linker. All sections should be explicitly named in the linker script.
1048ifdef CONFIG_LD_ORPHAN_WARN
1049LDFLAGS_vmlinux += --orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL)
1050endif
1051
1052# Align the bit size of userspace programs with the kernel
1053KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1054KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1055
1056# make the checker run with the right architecture
1057CHECKFLAGS += --arch=$(ARCH)
1058
1059# insure the checker run with the right endianness
1060CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1061
1062# the checker needs the correct machine size
1063CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1064
1065# Default kernel image to build when no specific target is given.
1066# KBUILD_IMAGE may be overruled on the command line or
1067# set in the environment
1068# Also any assignments in arch/$(ARCH)/Makefile take precedence over
1069# this default value
1070export KBUILD_IMAGE ?= vmlinux
1071
1072#
1073# INSTALL_PATH specifies where to place the updated kernel and system map
1074# images. Default is /boot, but you can set it to other values
1075export	INSTALL_PATH ?= /boot
1076
1077#
1078# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1079# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1080# an argument if needed. Otherwise it defaults to the kernel install path
1081#
1082export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1083
1084#
1085# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1086# relocations required by build roots.  This is not defined in the
1087# makefile but the argument can be passed to make if needed.
1088#
1089
1090MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1091export MODLIB
1092
1093PHONY += prepare0
1094
1095export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
1096export MODORDER := $(extmod_prefix)modules.order
1097export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
1098
1099ifeq ($(KBUILD_EXTMOD),)
1100
1101build-dir	:= .
1102clean-dirs	:= $(sort . Documentation \
1103		     $(patsubst %/,%,$(filter %/, $(core-) \
1104			$(drivers-) $(libs-))))
1105
1106export ARCH_CORE	:= $(core-y)
1107export ARCH_LIB		:= $(filter %/, $(libs-y))
1108export ARCH_DRIVERS	:= $(drivers-y) $(drivers-m)
1109# Externally visible symbols (used by link-vmlinux.sh)
1110
1111KBUILD_VMLINUX_OBJS := ./built-in.a
1112ifdef CONFIG_MODULES
1113KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1114KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1115else
1116KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1117endif
1118
1119export KBUILD_VMLINUX_LIBS
1120export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1121
1122ifdef CONFIG_TRIM_UNUSED_KSYMS
1123# For the kernel to actually contain only the needed exported symbols,
1124# we have to build modules as well to determine what those symbols are.
1125KBUILD_MODULES := 1
1126endif
1127
1128# '$(AR) mPi' needs 'T' to workaround the bug of llvm-ar <= 14
1129quiet_cmd_ar_vmlinux.a = AR      $@
1130      cmd_ar_vmlinux.a = \
1131	rm -f $@; \
1132	$(AR) cDPrST $@ $(KBUILD_VMLINUX_OBJS); \
1133	$(AR) mPiT $$($(AR) t $@ | sed -n 1p) $@ $$($(AR) t $@ | grep -F -f $(srctree)/scripts/head-object-list.txt)
1134
1135targets += vmlinux.a
1136vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt FORCE
1137	$(call if_changed,ar_vmlinux.a)
1138
1139PHONY += vmlinux_o
1140vmlinux_o: vmlinux.a $(KBUILD_VMLINUX_LIBS)
1141	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o
1142
1143vmlinux.o modules.builtin.modinfo modules.builtin: vmlinux_o
1144	@:
1145
1146PHONY += vmlinux
1147# LDFLAGS_vmlinux in the top Makefile defines linker flags for the top vmlinux,
1148# not for decompressors. LDFLAGS_vmlinux in arch/*/boot/compressed/Makefile is
1149# unrelated; the decompressors just happen to have the same base name,
1150# arch/*/boot/compressed/vmlinux.
1151# Export LDFLAGS_vmlinux only to scripts/Makefile.vmlinux.
1152#
1153# _LDFLAGS_vmlinux is a workaround for the 'private export' bug:
1154#   https://savannah.gnu.org/bugs/?61463
1155# For Make > 4.4, the following simple code will work:
1156#  vmlinux: private export LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1157vmlinux: private _LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1158vmlinux: export LDFLAGS_vmlinux = $(_LDFLAGS_vmlinux)
1159vmlinux: __KEEPMAKEFILEO__C.o $(KBUILD_LDS) modpost
1160	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux
1161
1162# The actual objects are generated when descending,
1163# make sure no implicit rule kicks in
1164$(sort $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)): . ;
1165
1166ifeq ($(origin KERNELRELEASE),file)
1167filechk_kernel.release = $(srctree)/scripts/setlocalversion $(srctree)
1168else
1169filechk_kernel.release = echo $(KERNELRELEASE)
1170endif
1171
1172# Store (new) KERNELRELEASE string in include/config/kernel.release
1173include/config/kernel.release: FORCE
1174	$(call filechk,kernel.release)
1175
1176# Additional helpers built in scripts
1177# Carefully list dependencies so we do not try to build scripts twice
1178# in parallel
1179PHONY += scripts
1180scripts: scripts_basic scripts_dtc
1181	$(Q)$(MAKE) $(build)=$(@)
1182
1183# Things we need to do before we recursively start building the kernel
1184# or the modules are listed in "prepare".
1185# A multi level approach is used. prepareN is processed before prepareN-1.
1186# archprepare is used in arch Makefiles and when processed asm symlink,
1187# version.h and scripts_basic is processed / created.
1188
1189PHONY += prepare archprepare
1190
1191archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1192	asm-generic $(version_h) include/generated/utsrelease.h \
1193	include/generated/compile.h include/generated/autoconf.h remove-stale-files
1194
1195prepare0: archprepare
1196	$(Q)$(MAKE) $(build)=scripts/mod
1197	$(Q)$(MAKE) $(build)=. prepare
1198
1199# All the preparing..
1200prepare: prepare0
1201ifdef CONFIG_RUST
1202	+$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh
1203	$(Q)$(MAKE) $(build)=rust
1204endif
1205
1206PHONY += remove-stale-files
1207remove-stale-files:
1208	$(Q)$(srctree)/scripts/remove-stale-files
1209
1210# Support for using generic headers in asm-generic
1211asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1212
1213PHONY += asm-generic uapi-asm-generic
1214asm-generic: uapi-asm-generic
1215	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1216	generic=include/asm-generic
1217uapi-asm-generic:
1218	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1219	generic=include/uapi/asm-generic
1220
1221# Generate some files
1222# ---------------------------------------------------------------------------
1223
1224# KERNELRELEASE can change from a few different places, meaning version.h
1225# needs to be updated, so this check is forced on all builds
1226
1227uts_len := 64
1228define filechk_utsrelease.h
1229	if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1230	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1231	  exit 1;                                                         \
1232	fi;                                                               \
1233	echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1234endef
1235
1236define filechk_version.h
1237	if [ $(SUBLEVEL) -gt 255 ]; then                                 \
1238		echo \#define LINUX_VERSION_CODE $(shell                 \
1239		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1240	else                                                             \
1241		echo \#define LINUX_VERSION_CODE $(shell                 \
1242		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1243	fi;                                                              \
1244	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
1245	((c) > 255 ? 255 : (c)))';                                       \
1246	echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
1247	echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
1248	echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1249endef
1250
1251$(version_h): PATCHLEVEL := $(or $(PATCHLEVEL), 0)
1252$(version_h): SUBLEVEL := $(or $(SUBLEVEL), 0)
1253$(version_h): FORCE
1254	$(call filechk,version.h)
1255
1256include/generated/utsrelease.h: include/config/kernel.release FORCE
1257	$(call filechk,utsrelease.h)
1258
1259filechk_compile.h = $(srctree)/scripts/mkcompile_h \
1260	"$(UTS_MACHINE)" "$(CONFIG_CC_VERSION_TEXT)" "$(LD)"
1261
1262include/generated/compile.h: FORCE
1263	$(call filechk,compile.h)
1264
1265PHONY += headerdep
1266headerdep:
1267	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1268	$(srctree)/scripts/headerdep.pl -I$(srctree)/include
1269
1270# ---------------------------------------------------------------------------
1271# Kernel headers
1272
1273#Default location for installed headers
1274export INSTALL_HDR_PATH = $(objtree)/usr
1275
1276quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1277      cmd_headers_install = \
1278	mkdir -p $(INSTALL_HDR_PATH); \
1279	rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1280	usr/include $(INSTALL_HDR_PATH)
1281
1282PHONY += headers_install
1283headers_install: headers
1284	$(call cmd,headers_install)
1285
1286PHONY += archheaders archscripts
1287
1288hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1289
1290PHONY += headers
1291headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1292	$(if $(filter um, $(SRCARCH)), $(error Headers not exportable for UML))
1293	$(Q)$(MAKE) $(hdr-inst)=include/uapi
1294	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1295
1296ifdef CONFIG_HEADERS_INSTALL
1297prepare: headers
1298endif
1299
1300PHONY += scripts_unifdef
1301scripts_unifdef: scripts_basic
1302	$(Q)$(MAKE) $(build)=scripts scripts/unifdef
1303
1304# ---------------------------------------------------------------------------
1305# Install
1306
1307# Many distributions have the custom install script, /sbin/installkernel.
1308# If DKMS is installed, 'make install' will eventually recurse back
1309# to this Makefile to build and install external modules.
1310# Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
1311
1312quiet_cmd_install = INSTALL $(INSTALL_PATH)
1313      cmd_install = unset sub_make_done; $(srctree)/scripts/install.sh
1314
1315# ---------------------------------------------------------------------------
1316# vDSO install
1317
1318PHONY += vdso_install
1319vdso_install: export INSTALL_FILES = $(vdso-install-y)
1320vdso_install:
1321	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vdsoinst
1322
1323# ---------------------------------------------------------------------------
1324# Tools
1325
1326ifdef CONFIG_OBJTOOL
1327prepare: tools/objtool
1328endif
1329
1330ifdef CONFIG_BPF
1331ifdef CONFIG_DEBUG_INFO_BTF
1332prepare: tools/bpf/resolve_btfids
1333endif
1334endif
1335
1336PHONY += resolve_btfids_clean
1337
1338resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1339
1340# tools/bpf/resolve_btfids directory might not exist
1341# in output directory, skip its clean in that case
1342resolve_btfids_clean:
1343ifneq ($(wildcard $(resolve_btfids_O)),)
1344	$(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1345endif
1346
1347# Clear a bunch of variables before executing the submake
1348ifeq ($(quiet),silent_)
1349tools_silent=s
1350endif
1351
1352tools/: FORCE
1353	$(Q)mkdir -p $(objtree)/tools
1354	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1355
1356tools/%: FORCE
1357	$(Q)mkdir -p $(objtree)/tools
1358	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1359
1360# ---------------------------------------------------------------------------
1361# Kernel selftest
1362
1363PHONY += kselftest
1364kselftest: headers
1365	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1366
1367kselftest-%: headers FORCE
1368	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1369
1370PHONY += kselftest-merge
1371kselftest-merge:
1372	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1373	$(Q)find $(srctree)/tools/testing/selftests -name config -o -name config.$(UTS_MACHINE) | \
1374		xargs $(srctree)/scripts/kconfig/merge_config.sh -y -m $(objtree)/.config
1375	$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1376
1377# ---------------------------------------------------------------------------
1378# Devicetree files
1379
1380ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1381dtstree := arch/$(SRCARCH)/boot/dts
1382endif
1383
1384ifneq ($(dtstree),)
1385
1386%.dtb: dtbs_prepare
1387	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1388
1389%.dtbo: dtbs_prepare
1390	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1391
1392PHONY += dtbs dtbs_prepare dtbs_install dtbs_check
1393dtbs: dtbs_prepare
1394	$(Q)$(MAKE) $(build)=$(dtstree) need-dtbslist=1
1395
1396# include/config/kernel.release is actually needed when installing DTBs because
1397# INSTALL_DTBS_PATH contains $(KERNELRELEASE). However, we do not want to make
1398# dtbs_install depend on it as dtbs_install may run as root.
1399dtbs_prepare: include/config/kernel.release scripts_dtc
1400
1401ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1402export CHECK_DTBS=y
1403endif
1404
1405ifneq ($(CHECK_DTBS),)
1406dtbs_prepare: dt_binding_check
1407endif
1408
1409dtbs_check: dtbs
1410
1411dtbs_install:
1412	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.dtbinst obj=$(dtstree)
1413
1414ifdef CONFIG_OF_EARLY_FLATTREE
1415all: dtbs
1416endif
1417
1418endif
1419
1420PHONY += scripts_dtc
1421scripts_dtc: scripts_basic
1422	$(Q)$(MAKE) $(build)=scripts/dtc
1423
1424ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1425export CHECK_DT_BINDING=y
1426endif
1427
1428PHONY += dt_binding_check
1429dt_binding_check: scripts_dtc
1430	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1431
1432PHONY += dt_compatible_check
1433dt_compatible_check: dt_binding_check
1434	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1435
1436# ---------------------------------------------------------------------------
1437# Modules
1438
1439ifdef CONFIG_MODULES
1440
1441# By default, build modules as well
1442
1443all: modules
1444
1445# When we're building modules with modversions, we need to consider
1446# the built-in objects during the descend as well, in order to
1447# make sure the checksums are up to date before we record them.
1448ifdef CONFIG_MODVERSIONS
1449  KBUILD_BUILTIN := 1
1450endif
1451
1452# Build modules
1453#
1454
1455# *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFO_BTF_MODULES
1456# is an exception.
1457ifdef CONFIG_DEBUG_INFO_BTF_MODULES
1458KBUILD_BUILTIN := 1
1459modules: vmlinux
1460endif
1461
1462modules: modules_prepare
1463
1464# Target to prepare building external modules
1465modules_prepare: prepare
1466	$(Q)$(MAKE) $(build)=scripts scripts/module.lds
1467
1468endif # CONFIG_MODULES
1469
1470###
1471# Cleaning is done on three levels.
1472# make clean     Delete most generated files
1473#                Leave enough to build external modules
1474# make mrproper  Delete the current configuration, and all generated files
1475# make distclean Remove editor backup files, patch leftover files and the like
1476
1477# Directories & files removed with 'make clean'
1478CLEAN_FILES += vmlinux.symvers modules-only.symvers \
1479	       modules.builtin modules.builtin.modinfo modules.nsdeps \
1480	       compile_commands.json .thinlto-cache rust/test \
1481	       rust-project.json .vmlinux.objs .vmlinux.export.c
1482
1483# Directories & files removed with 'make mrproper'
1484MRPROPER_FILES += include/config include/generated          \
1485		  arch/$(SRCARCH)/include/generated .objdiff \
1486		  debian snap tar-install \
1487		  .config .config.old .version \
1488		  Module.symvers \
1489		  certs/signing_key.pem \
1490		  certs/x509.genkey \
1491		  vmlinux-gdb.py \
1492		  rpmbuild \
1493		  rust/libmacros.so
1494
1495# clean - Delete most, but leave enough to build external modules
1496#
1497clean: rm-files := $(CLEAN_FILES)
1498
1499PHONY += archclean vmlinuxclean
1500
1501vmlinuxclean:
1502	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1503	$(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1504
1505clean: archclean vmlinuxclean resolve_btfids_clean
1506
1507# mrproper - Delete all generated files, including .config
1508#
1509mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1510mrproper-dirs      := $(addprefix _mrproper_,scripts)
1511
1512PHONY += $(mrproper-dirs) mrproper
1513$(mrproper-dirs):
1514	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1515
1516mrproper: clean $(mrproper-dirs)
1517	$(call cmd,rmfiles)
1518	@find . $(RCS_FIND_IGNORE) \
1519		\( -name '*.rmeta' \) \
1520		-type f -print | xargs rm -f
1521
1522# distclean
1523#
1524PHONY += distclean
1525
1526distclean: mrproper
1527	@find . $(RCS_FIND_IGNORE) \
1528		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1529		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
1530		-o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1531		-o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1532		-type f -print | xargs rm -f
1533
1534
1535# Packaging of the kernel to various formats
1536# ---------------------------------------------------------------------------
1537
1538%src-pkg: FORCE
1539	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1540%pkg: include/config/kernel.release FORCE
1541	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1542
1543# Brief documentation of the typical targets used
1544# ---------------------------------------------------------------------------
1545
1546boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1547boards := $(sort $(notdir $(boards)))
1548board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1549board-dirs := $(sort $(notdir $(board-dirs:/=)))
1550
1551PHONY += help
1552help:
1553	@echo  'Cleaning targets:'
1554	@echo  '  clean		  - Remove most generated files but keep the config and'
1555	@echo  '                    enough build support to build external modules'
1556	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
1557	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
1558	@echo  ''
1559	@$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1560	@echo  ''
1561	@echo  'Other generic targets:'
1562	@echo  '  all		  - Build all targets marked with [*]'
1563	@echo  '* vmlinux	  - Build the bare kernel'
1564	@echo  '* modules	  - Build all modules'
1565	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1566	@echo  '  vdso_install    - Install unstripped vdso to INSTALL_MOD_PATH (default: /)'
1567	@echo  '  dir/            - Build all files in dir and below'
1568	@echo  '  dir/file.[ois]  - Build specified target only'
1569	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1570	@echo  '                    (requires compiler support for LLVM assembly generation)'
1571	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1572	@echo  '                    (requires a recent binutils and recent build (System.map))'
1573	@echo  '  dir/file.ko     - Build module including final link'
1574	@echo  '  modules_prepare - Set up for building external modules'
1575	@echo  '  tags/TAGS	  - Generate tags file for editors'
1576	@echo  '  cscope	  - Generate cscope index'
1577	@echo  '  gtags           - Generate GNU GLOBAL index'
1578	@echo  '  kernelrelease	  - Output the release version string (use with make -s)'
1579	@echo  '  kernelversion	  - Output the version stored in Makefile (use with make -s)'
1580	@echo  '  image_name	  - Output the image name (use with make -s)'
1581	@echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1582	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1583	 echo  ''
1584	@echo  'Static analysers:'
1585	@echo  '  checkstack      - Generate a list of stack hogs and consider all functions'
1586	@echo  '                    with a stack size larger than MINSTACKSIZE (default: 100)'
1587	@echo  '  versioncheck    - Sanity check on version.h usage'
1588	@echo  '  includecheck    - Check for duplicate included header files'
1589	@echo  '  export_report   - List the usages of all exported symbols'
1590	@echo  '  headerdep       - Detect inclusion cycles in headers'
1591	@echo  '  coccicheck      - Check with Coccinelle'
1592	@echo  '  clang-analyzer  - Check with clang static analyzer'
1593	@echo  '  clang-tidy      - Check with clang-tidy'
1594	@echo  ''
1595	@echo  'Tools:'
1596	@echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1597	@echo  ''
1598	@echo  'Kernel selftest:'
1599	@echo  '  kselftest         - Build and run kernel selftest'
1600	@echo  '                      Build, install, and boot kernel before'
1601	@echo  '                      running kselftest on it'
1602	@echo  '                      Run as root for full coverage'
1603	@echo  '  kselftest-all     - Build kernel selftest'
1604	@echo  '  kselftest-install - Build and install kernel selftest'
1605	@echo  '  kselftest-clean   - Remove all generated kselftest files'
1606	@echo  '  kselftest-merge   - Merge all the config dependencies of'
1607	@echo  '		      kselftest to existing .config.'
1608	@echo  ''
1609	@echo  'Rust targets:'
1610	@echo  '  rustavailable   - Checks whether the Rust toolchain is'
1611	@echo  '		    available and, if not, explains why.'
1612	@echo  '  rustfmt	  - Reformat all the Rust code in the kernel'
1613	@echo  '  rustfmtcheck	  - Checks if all the Rust code in the kernel'
1614	@echo  '		    is formatted, printing a diff otherwise.'
1615	@echo  '  rustdoc	  - Generate Rust documentation'
1616	@echo  '		    (requires kernel .config)'
1617	@echo  '  rusttest        - Runs the Rust tests'
1618	@echo  '                    (requires kernel .config; downloads external repos)'
1619	@echo  '  rust-analyzer	  - Generate rust-project.json rust-analyzer support file'
1620	@echo  '		    (requires kernel .config)'
1621	@echo  '  dir/file.[os]   - Build specified target only'
1622	@echo  '  dir/file.rsi    - Build macro expanded source, similar to C preprocessing.'
1623	@echo  '                    Run with RUSTFMT=n to skip reformatting if needed.'
1624	@echo  '                    The output is not intended to be compilable.'
1625	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1626	@echo  ''
1627	@$(if $(dtstree), \
1628		echo 'Devicetree:'; \
1629		echo '* dtbs             - Build device tree blobs for enabled boards'; \
1630		echo '  dtbs_install     - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1631		echo '  dt_binding_check - Validate device tree binding documents'; \
1632		echo '  dtbs_check       - Validate device tree source files';\
1633		echo '')
1634
1635	@echo 'Userspace tools targets:'
1636	@echo '  use "make tools/help"'
1637	@echo '  or  "cd tools; make help"'
1638	@echo  ''
1639	@echo  'Kernel packaging:'
1640	@$(MAKE) -f $(srctree)/scripts/Makefile.package help
1641	@echo  ''
1642	@echo  'Documentation targets:'
1643	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1644	@echo  ''
1645	@echo  'Architecture-specific targets ($(SRCARCH)):'
1646	@$(or $(archhelp),\
1647		echo '  No architecture-specific help defined for $(SRCARCH)')
1648	@echo  ''
1649	@$(if $(boards), \
1650		$(foreach b, $(boards), \
1651		printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1652		echo '')
1653	@$(if $(board-dirs), \
1654		$(foreach b, $(board-dirs), \
1655		printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1656		printf "  %-16s - Show all of the above\\n" help-boards; \
1657		echo '')
1658
1659	@echo  '  make V=n   [targets] 1: verbose build'
1660	@echo  '                       2: give reason for rebuild of target'
1661	@echo  '                       V=1 and V=2 can be combined with V=12'
1662	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1663	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1664	@echo  '                       (sparse by default)'
1665	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1666	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1667	@echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3,c,e where'
1668	@echo  '		1: warnings which may be relevant and do not occur too often'
1669	@echo  '		2: warnings which occur quite often but may still be relevant'
1670	@echo  '		3: more obscure warnings, can most likely be ignored'
1671	@echo  '		c: extra checks in the configuration stage (Kconfig)'
1672	@echo  '		e: warnings are being treated as errors'
1673	@echo  '		Multiple levels can be combined with W=12 or W=123'
1674	@$(if $(dtstree), \
1675		echo '  make CHECK_DTBS=1 [targets] Check all generated dtb files against schema'; \
1676		echo '         This can be applied both to "dtbs" and to individual "foo.dtb" targets' ; \
1677		)
1678	@echo  ''
1679	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
1680	@echo  'For further info see the ./README file'
1681
1682
1683help-board-dirs := $(addprefix help-,$(board-dirs))
1684
1685help-boards: $(help-board-dirs)
1686
1687boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1688
1689$(help-board-dirs): help-%:
1690	@echo  'Architecture-specific targets ($(SRCARCH) $*):'
1691	@$(if $(boards-per-dir), \
1692		$(foreach b, $(boards-per-dir), \
1693		printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1694		echo '')
1695
1696
1697# Documentation targets
1698# ---------------------------------------------------------------------------
1699DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1700	       linkcheckdocs dochelp refcheckdocs texinfodocs infodocs
1701PHONY += $(DOC_TARGETS)
1702$(DOC_TARGETS):
1703	$(Q)$(MAKE) $(build)=Documentation $@
1704
1705
1706# Rust targets
1707# ---------------------------------------------------------------------------
1708
1709# "Is Rust available?" target
1710PHONY += rustavailable
1711rustavailable:
1712	+$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh && echo "Rust is available!"
1713
1714# Documentation target
1715#
1716# Using the singular to avoid running afoul of `no-dot-config-targets`.
1717PHONY += rustdoc
1718rustdoc: prepare
1719	$(Q)$(MAKE) $(build)=rust $@
1720
1721# Testing target
1722PHONY += rusttest
1723rusttest: prepare
1724	$(Q)$(MAKE) $(build)=rust $@
1725
1726# Formatting targets
1727PHONY += rustfmt rustfmtcheck
1728
1729# We skip `rust/alloc` since we want to minimize the diff w.r.t. upstream.
1730#
1731# We match using absolute paths since `find` does not resolve them
1732# when matching, which is a problem when e.g. `srctree` is `..`.
1733# We `grep` afterwards in order to remove the directory entry itself.
1734rustfmt:
1735	$(Q)find $(abs_srctree) -type f -name '*.rs' \
1736		-o -path $(abs_srctree)/rust/alloc -prune \
1737		-o -path $(abs_objtree)/rust/test -prune \
1738		| grep -Fv $(abs_srctree)/rust/alloc \
1739		| grep -Fv $(abs_objtree)/rust/test \
1740		| grep -Fv generated \
1741		| xargs $(RUSTFMT) $(rustfmt_flags)
1742
1743rustfmtcheck: rustfmt_flags = --check
1744rustfmtcheck: rustfmt
1745
1746# Misc
1747# ---------------------------------------------------------------------------
1748
1749PHONY += misc-check
1750misc-check:
1751	$(Q)$(srctree)/scripts/misc-check
1752
1753all: misc-check
1754
1755PHONY += scripts_gdb
1756scripts_gdb: prepare0
1757	$(Q)$(MAKE) $(build)=scripts/gdb
1758	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1759
1760ifdef CONFIG_GDB_SCRIPTS
1761all: scripts_gdb
1762endif
1763
1764else # KBUILD_EXTMOD
1765
1766filechk_kernel.release = echo $(KERNELRELEASE)
1767
1768###
1769# External module support.
1770# When building external modules the kernel used as basis is considered
1771# read-only, and no consistency checks are made and the make
1772# system is not used on the basis kernel. If updates are required
1773# in the basis kernel ordinary make commands (without M=...) must be used.
1774
1775# We are always building only modules.
1776KBUILD_BUILTIN :=
1777KBUILD_MODULES := 1
1778
1779build-dir := $(KBUILD_EXTMOD)
1780
1781compile_commands.json: $(extmod_prefix)compile_commands.json
1782PHONY += compile_commands.json
1783
1784clean-dirs := $(KBUILD_EXTMOD)
1785clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1786	$(KBUILD_EXTMOD)/compile_commands.json $(KBUILD_EXTMOD)/.thinlto-cache
1787
1788PHONY += prepare
1789# now expand this into a simple variable to reduce the cost of shell evaluations
1790prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT)
1791prepare:
1792	@if [ "$(CC_VERSION_TEXT)" != "$(CONFIG_CC_VERSION_TEXT)" ]; then \
1793		echo >&2 "warning: the compiler differs from the one used to build the kernel"; \
1794		echo >&2 "  The kernel was built by: $(CONFIG_CC_VERSION_TEXT)"; \
1795		echo >&2 "  You are using:           $(CC_VERSION_TEXT)"; \
1796	fi
1797
1798PHONY += help
1799help:
1800	@echo  '  Building external modules.'
1801	@echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1802	@echo  ''
1803	@echo  '  modules         - default target, build the module(s)'
1804	@echo  '  modules_install - install the module'
1805	@echo  '  clean           - remove generated files in module directory only'
1806	@echo  '  rust-analyzer	  - generate rust-project.json rust-analyzer support file'
1807	@echo  ''
1808
1809ifndef CONFIG_MODULES
1810modules modules_install: __external_modules_error
1811__external_modules_error:
1812	@echo >&2 '***'
1813	@echo >&2 '*** The present kernel disabled CONFIG_MODULES.'
1814	@echo >&2 '*** You cannot build or install external modules.'
1815	@echo >&2 '***'
1816	@false
1817endif
1818
1819endif # KBUILD_EXTMOD
1820
1821# ---------------------------------------------------------------------------
1822# Modules
1823
1824PHONY += modules modules_install modules_sign modules_prepare
1825
1826modules_install:
1827	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst \
1828	sign-only=$(if $(filter modules_install,$(MAKECMDGOALS)),,y)
1829
1830ifeq ($(CONFIG_MODULE_SIG),y)
1831# modules_sign is a subset of modules_install.
1832# 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1833modules_sign: modules_install
1834	@:
1835else
1836modules_sign:
1837	@echo >&2 '***'
1838	@echo >&2 '*** CONFIG_MODULE_SIG is disabled. You cannot sign modules.'
1839	@echo >&2 '***'
1840	@false
1841endif
1842
1843ifdef CONFIG_MODULES
1844
1845$(MODORDER): $(build-dir)
1846	@:
1847
1848# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
1849# This is solely useful to speed up test compiles.
1850modules: modpost
1851ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1852	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1853endif
1854
1855PHONY += modules_check
1856modules_check: $(MODORDER)
1857	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1858
1859else # CONFIG_MODULES
1860
1861modules:
1862	@:
1863
1864KBUILD_MODULES :=
1865
1866endif # CONFIG_MODULES
1867
1868PHONY += modpost
1869modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \
1870	 $(if $(KBUILD_MODULES), modules_check)
1871	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1872
1873# Single targets
1874# ---------------------------------------------------------------------------
1875# To build individual files in subdirectories, you can do like this:
1876#
1877#   make foo/bar/baz.s
1878#
1879# The supported suffixes for single-target are listed in 'single-targets'
1880#
1881# To build only under specific subdirectories, you can do like this:
1882#
1883#   make foo/bar/baz/
1884
1885ifdef single-build
1886
1887# .ko is special because modpost is needed
1888single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1889single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \
1890		$(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko)))
1891
1892$(single-ko): single_modules
1893	@:
1894$(single-no-ko): $(build-dir)
1895	@:
1896
1897# Remove MODORDER when done because it is not the real one.
1898PHONY += single_modules
1899single_modules: $(single-no-ko) modules_prepare
1900	$(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$(m:%.ko=%.o);) } > $(MODORDER)
1901	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1902ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1903	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1904endif
1905	$(Q)rm -f $(MODORDER)
1906
1907single-goals := $(addprefix $(build-dir)/, $(single-no-ko))
1908
1909KBUILD_MODULES := 1
1910
1911endif
1912
1913# Preset locale variables to speed up the build process. Limit locale
1914# tweaks to this spot to avoid wrong language settings when running
1915# make menuconfig etc.
1916# Error messages still appears in the original language
1917PHONY += $(build-dir)
1918$(build-dir): prepare
1919	$(Q)$(MAKE) $(build)=$@ need-builtin=1 need-modorder=1 $(single-goals)
1920
1921clean-dirs := $(addprefix _clean_, $(clean-dirs))
1922PHONY += $(clean-dirs) clean
1923$(clean-dirs):
1924	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1925
1926clean: $(clean-dirs)
1927	$(call cmd,rmfiles)
1928	@find $(or $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1929		\( -name '*.[aios]' -o -name '*.rsi' -o -name '*.ko' -o -name '.*.cmd' \
1930		-o -name '*.ko.*' \
1931		-o -name '*.dtb' -o -name '*.dtbo' \
1932		-o -name '*.dtb.S' -o -name '*.dtbo.S' \
1933		-o -name '*.dt.yaml' -o -name 'dtbs-list' \
1934		-o -name '*.dwo' -o -name '*.lst' \
1935		-o -name '*.su' -o -name '*.mod' \
1936		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1937		-o -name '*.lex.c' -o -name '*.tab.[ch]' \
1938		-o -name '*.asn1.[ch]' \
1939		-o -name '*.symtypes' -o -name 'modules.order' \
1940		-o -name '*.c.[012]*.*' \
1941		-o -name '*.ll' \
1942		-o -name '*.gcno' \
1943		-o -name '*.*.symversions' \) -type f -print \
1944		-o -name '.tmp_*' -print \
1945		| xargs rm -rf
1946
1947# Generate tags for editors
1948# ---------------------------------------------------------------------------
1949quiet_cmd_tags = GEN     $@
1950      cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1951
1952tags TAGS cscope gtags: FORCE
1953	$(call cmd,tags)
1954
1955# IDE support targets
1956PHONY += rust-analyzer
1957rust-analyzer:
1958	$(Q)$(MAKE) $(build)=rust $@
1959
1960# Script to generate missing namespace dependencies
1961# ---------------------------------------------------------------------------
1962
1963PHONY += nsdeps
1964nsdeps: export KBUILD_NSDEPS=1
1965nsdeps: modules
1966	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1967
1968# Clang Tooling
1969# ---------------------------------------------------------------------------
1970
1971quiet_cmd_gen_compile_commands = GEN     $@
1972      cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
1973
1974$(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
1975	$(if $(KBUILD_EXTMOD),, vmlinux.a $(KBUILD_VMLINUX_LIBS)) \
1976	$(if $(CONFIG_MODULES), $(MODORDER)) FORCE
1977	$(call if_changed,gen_compile_commands)
1978
1979targets += $(extmod_prefix)compile_commands.json
1980
1981PHONY += clang-tidy clang-analyzer
1982
1983ifdef CONFIG_CC_IS_CLANG
1984quiet_cmd_clang_tools = CHECK   $<
1985      cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
1986
1987clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
1988	$(call cmd,clang_tools)
1989else
1990clang-tidy clang-analyzer:
1991	@echo "$@ requires CC=clang" >&2
1992	@false
1993endif
1994
1995# Scripts to check various things for consistency
1996# ---------------------------------------------------------------------------
1997
1998PHONY += includecheck versioncheck coccicheck export_report
1999
2000includecheck:
2001	find $(srctree)/* $(RCS_FIND_IGNORE) \
2002		-name '*.[hcS]' -type f -print | sort \
2003		| xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
2004
2005versioncheck:
2006	find $(srctree)/* $(RCS_FIND_IGNORE) \
2007		-name '*.[hcS]' -type f -print | sort \
2008		| xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
2009
2010coccicheck:
2011	$(Q)$(BASH) $(srctree)/scripts/$@
2012
2013export_report:
2014	$(PERL) $(srctree)/scripts/export_report.pl
2015
2016PHONY += checkstack kernelrelease kernelversion image_name
2017
2018# UML needs a little special treatment here.  It wants to use the host
2019# toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
2020# else wants $(ARCH), including people doing cross-builds, which means
2021# that $(SUBARCH) doesn't work here.
2022ifeq ($(ARCH), um)
2023CHECKSTACK_ARCH := $(SUBARCH)
2024else
2025CHECKSTACK_ARCH := $(ARCH)
2026endif
2027MINSTACKSIZE	?= 100
2028checkstack:
2029	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
2030	$(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH) $(MINSTACKSIZE)
2031
2032kernelrelease:
2033	@$(filechk_kernel.release)
2034
2035kernelversion:
2036	@echo $(KERNELVERSION)
2037
2038image_name:
2039	@echo $(KBUILD_IMAGE)
2040
2041PHONY += run-command
2042run-command:
2043	$(Q)$(KBUILD_RUN_COMMAND)
2044
2045quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
2046      cmd_rmfiles = rm -rf $(rm-files)
2047
2048# read saved command lines for existing targets
2049existing-targets := $(wildcard $(sort $(targets)))
2050
2051-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
2052
2053endif # config-build
2054endif # mixed-build
2055endif # need-sub-make
2056
2057PHONY += FORCE
2058FORCE:
2059
2060# Declare the contents of the PHONY variable as phony.  We keep that
2061# information in a variable so we can use it in if_changed and friends.
2062.PHONY: $(PHONY)