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   1# SPDX-License-Identifier: GPL-2.0
   2VERSION = 6
   3PATCHLEVEL = 7
   4SUBLEVEL = 1
   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))
  42export abs_srctree := $(realpath $(dir $(this-makefile)))
  43export abs_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 $(KBUILD_EXTMOD).)
 154endif
 155
 156export KBUILD_EXTMOD
 157
 158# Kbuild will save output files in the current working directory.
 159# This does not need to match to the root of the kernel source tree.
 160#
 161# For example, you can do this:
 162#
 163#  cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
 164#
 165# If you want to save output files in a different location, there are
 166# two syntaxes to specify it.
 167#
 168# 1) O=
 169# Use "make O=dir/to/store/output/files/"
 170#
 171# 2) Set KBUILD_OUTPUT
 172# Set the environment variable KBUILD_OUTPUT to point to the output directory.
 173# export KBUILD_OUTPUT=dir/to/store/output/files/; make
 174#
 175# The O= assignment takes precedence over the KBUILD_OUTPUT environment
 176# variable.
 177
 178# Do we want to change the working directory?
 179ifeq ("$(origin O)", "command line")
 180  KBUILD_OUTPUT := $(O)
 181endif
 182
 183ifneq ($(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.
 186abs_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
 191abs_objtree := $(realpath $(abs_objtree))
 192endif # ifneq ($(KBUILD_OUTPUT),)
 193
 194ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
 195$(error source directory cannot contain spaces or colons)
 196endif
 197
 198ifneq ($(filter 3.%,$(MAKE_VERSION)),)
 199# 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
 200# We need to invoke sub-make to avoid implicit rules in the top Makefile.
 201need-sub-make := 1
 202# Cancel implicit rules for this Makefile.
 203$(this-makefile): ;
 204endif
 205
 206export sub_make_done := 1
 207
 208endif # sub_make_done
 209
 210ifeq ($(abs_objtree),$(CURDIR))
 211# Suppress "Entering directory ..." if we are at the final work directory.
 212no-print-directory := --no-print-directory
 213else
 214# Recursion to show "Entering directory ..."
 215need-sub-make := 1
 216endif
 217
 218ifeq ($(filter --no-print-directory, $(MAKEFLAGS)),)
 219# If --no-print-directory is unset, recurse once again to set it.
 220# You may end up recursing into __sub-make twice. This is needed due to the
 221# behavior change in GNU Make 4.4.1.
 222need-sub-make := 1
 223endif
 224
 225ifeq ($(need-sub-make),1)
 226
 227PHONY += $(MAKECMDGOALS) __sub-make
 228
 229$(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 $(MAKECMDGOALS)
 236
 237else # need-sub-make
 238
 239# We process the rest of the Makefile if this is the final invocation of make
 240
 241ifeq ($(abs_srctree),$(abs_objtree))
 242        # building in the source tree
 243        srctree := .
 244        building_out_of_srctree :=
 245else
 246        ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
 247                # building in a subdirectory of the source tree
 248                srctree := ..
 249        else
 250                srctree := $(abs_srctree)
 251        endif
 252        building_out_of_srctree := 1
 253endif
 254
 255ifneq ($(KBUILD_ABS_SRCTREE),)
 256srctree := $(abs_srctree)
 257endif
 258
 259objtree         := .
 260VPATH           := $(srctree)
 261
 262export 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
 272version_h := include/generated/uapi/linux/version.h
 273
 274clean-targets := %clean mrproper cleandocs
 275no-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
 280no-sync-config-targets := $(no-dot-config-targets) %install modules_sign kernelrelease \
 281                          image_name
 282single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.rsi %.s %.symtypes %/
 283
 284config-build    :=
 285mixed-build     :=
 286need-config     := 1
 287may-sync-config := 1
 288single-build    :=
 289
 290ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
 291        ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
 292                need-config :=
 293        endif
 294endif
 295
 296ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
 297        ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
 298                may-sync-config :=
 299        endif
 300endif
 301
 302need-compiler := $(may-sync-config)
 303
 304ifneq ($(KBUILD_EXTMOD),)
 305        may-sync-config :=
 306endif
 307
 308ifeq ($(KBUILD_EXTMOD),)
 309        ifneq ($(filter %config,$(MAKECMDGOALS)),)
 310                config-build := 1
 311                ifneq ($(words $(MAKECMDGOALS)),1)
 312                        mixed-build := 1
 313                endif
 314        endif
 315endif
 316
 317# We cannot build single targets and the others at the same time
 318ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
 319        single-build := 1
 320        ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
 321                mixed-build := 1
 322        endif
 323endif
 324
 325# For "make -j clean all", "make -j mrproper defconfig all", etc.
 326ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
 327        ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
 328                mixed-build := 1
 329        endif
 330endif
 331
 332# install and modules_install need also be processed one by one
 333ifneq ($(filter install,$(MAKECMDGOALS)),)
 334        ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
 335                mixed-build := 1
 336        endif
 337endif
 338
 339ifdef mixed-build
 340# ===========================================================================
 341# We're called with mixed targets (*config and build targets).
 342# Handle them one by one.
 343
 344PHONY += $(MAKECMDGOALS) __build_one_by_one
 345
 346$(MAKECMDGOALS): __build_one_by_one
 347        @:
 348
 349__build_one_by_one:
 350        $(Q)set -e; \
 351        for i in $(MAKECMDGOALS); do \
 352                $(MAKE) -f $(srctree)/Makefile $$i; \
 353        done
 354
 355else # !mixed-build
 356
 357include $(srctree)/scripts/Kbuild.include
 358
 359# Read KERNELRELEASE from include/config/kernel.release (if it exists)
 360KERNELRELEASE = $(call read-file, include/config/kernel.release)
 361KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
 362export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
 363
 364include $(srctree)/scripts/subarch.include
 365
 366# Cross compiling and selecting different set of gcc/bin-utils
 367# ---------------------------------------------------------------------------
 368#
 369# When performing cross compilation for other architectures ARCH shall be set
 370# to the target architecture. (See arch/* for the possibilities).
 371# ARCH can be set during invocation of make:
 372# make ARCH=arm64
 373# Another way is to have ARCH set in the environment.
 374# The default ARCH is the host where make is executed.
 375
 376# CROSS_COMPILE specify the prefix used for all executables used
 377# during compilation. Only gcc and related bin-utils executables
 378# are prefixed with $(CROSS_COMPILE).
 379# CROSS_COMPILE can be set on the command line
 380# make CROSS_COMPILE=aarch64-linux-gnu-
 381# Alternatively CROSS_COMPILE can be set in the environment.
 382# Default value for CROSS_COMPILE is not to prefix executables
 383# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
 384ARCH            ?= $(SUBARCH)
 385
 386# Architecture as present in compile.h
 387UTS_MACHINE     := $(ARCH)
 388SRCARCH         := $(ARCH)
 389
 390# Additional ARCH settings for x86
 391ifeq ($(ARCH),i386)
 392        SRCARCH := x86
 393endif
 394ifeq ($(ARCH),x86_64)
 395        SRCARCH := x86
 396endif
 397
 398# Additional ARCH settings for sparc
 399ifeq ($(ARCH),sparc32)
 400       SRCARCH := sparc
 401endif
 402ifeq ($(ARCH),sparc64)
 403       SRCARCH := sparc
 404endif
 405
 406# Additional ARCH settings for parisc
 407ifeq ($(ARCH),parisc64)
 408       SRCARCH := parisc
 409endif
 410
 411export cross_compiling :=
 412ifneq ($(SRCARCH),$(SUBARCH))
 413cross_compiling := 1
 414endif
 415
 416KCONFIG_CONFIG  ?= .config
 417export KCONFIG_CONFIG
 418
 419# SHELL used by kbuild
 420CONFIG_SHELL := sh
 421
 422HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
 423HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
 424HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
 425
 426ifneq ($(LLVM),)
 427ifneq ($(filter %/,$(LLVM)),)
 428LLVM_PREFIX := $(LLVM)
 429else ifneq ($(filter -%,$(LLVM)),)
 430LLVM_SUFFIX := $(LLVM)
 431endif
 432
 433HOSTCC  = $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
 434HOSTCXX = $(LLVM_PREFIX)clang++$(LLVM_SUFFIX)
 435else
 436HOSTCC  = gcc
 437HOSTCXX = g++
 438endif
 439HOSTRUSTC = rustc
 440HOSTPKG_CONFIG  = pkg-config
 441
 442KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
 443                         -O2 -fomit-frame-pointer -std=gnu11
 444KBUILD_USERCFLAGS  := $(KBUILD_USERHOSTCFLAGS) $(USERCFLAGS)
 445KBUILD_USERLDFLAGS := $(USERLDFLAGS)
 446
 447# These flags apply to all Rust code in the tree, including the kernel and
 448# host programs.
 449export rust_common_flags := --edition=2021 \
 450                            -Zbinary_dep_depinfo=y \
 451                            -Dunsafe_op_in_unsafe_fn -Drust_2018_idioms \
 452                            -Dunreachable_pub -Dnon_ascii_idents \
 453                            -Wmissing_docs \
 454                            -Drustdoc::missing_crate_level_docs \
 455                            -Dclippy::correctness -Dclippy::style \
 456                            -Dclippy::suspicious -Dclippy::complexity \
 457                            -Dclippy::perf \
 458                            -Dclippy::let_unit_value -Dclippy::mut_mut \
 459                            -Dclippy::needless_bitwise_bool \
 460                            -Dclippy::needless_continue \
 461                            -Dclippy::no_mangle_with_rust_abi \
 462                            -Wclippy::dbg_macro
 463
 464KBUILD_HOSTCFLAGS   := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
 465KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
 466KBUILD_HOSTRUSTFLAGS := $(rust_common_flags) -O -Cstrip=debuginfo \
 467                        -Zallow-features= $(HOSTRUSTFLAGS)
 468KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
 469KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
 470
 471# Make variables (CC, etc...)
 472CPP             = $(CC) -E
 473ifneq ($(LLVM),)
 474CC              = $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
 475LD              = $(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX)
 476AR              = $(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX)
 477NM              = $(LLVM_PREFIX)llvm-nm$(LLVM_SUFFIX)
 478OBJCOPY         = $(LLVM_PREFIX)llvm-objcopy$(LLVM_SUFFIX)
 479OBJDUMP         = $(LLVM_PREFIX)llvm-objdump$(LLVM_SUFFIX)
 480READELF         = $(LLVM_PREFIX)llvm-readelf$(LLVM_SUFFIX)
 481STRIP           = $(LLVM_PREFIX)llvm-strip$(LLVM_SUFFIX)
 482else
 483CC              = $(CROSS_COMPILE)gcc
 484LD              = $(CROSS_COMPILE)ld
 485AR              = $(CROSS_COMPILE)ar
 486NM              = $(CROSS_COMPILE)nm
 487OBJCOPY         = $(CROSS_COMPILE)objcopy
 488OBJDUMP         = $(CROSS_COMPILE)objdump
 489READELF         = $(CROSS_COMPILE)readelf
 490STRIP           = $(CROSS_COMPILE)strip
 491endif
 492RUSTC           = rustc
 493RUSTDOC         = rustdoc
 494RUSTFMT         = rustfmt
 495CLIPPY_DRIVER   = clippy-driver
 496BINDGEN         = bindgen
 497CARGO           = cargo
 498PAHOLE          = pahole
 499RESOLVE_BTFIDS  = $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
 500LEX             = flex
 501YACC            = bison
 502AWK             = awk
 503INSTALLKERNEL  := installkernel
 504PERL            = perl
 505PYTHON3         = python3
 506CHECK           = sparse
 507BASH            = bash
 508KGZIP           = gzip
 509KBZIP2          = bzip2
 510KLZOP           = lzop
 511LZMA            = lzma
 512LZ4             = lz4c
 513XZ              = xz
 514ZSTD            = zstd
 515
 516CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
 517                  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
 518NOSTDINC_FLAGS :=
 519CFLAGS_MODULE   =
 520RUSTFLAGS_MODULE =
 521AFLAGS_MODULE   =
 522LDFLAGS_MODULE  =
 523CFLAGS_KERNEL   =
 524RUSTFLAGS_KERNEL =
 525AFLAGS_KERNEL   =
 526LDFLAGS_vmlinux =
 527
 528# Use USERINCLUDE when you must reference the UAPI directories only.
 529USERINCLUDE    := \
 530                -I$(srctree)/arch/$(SRCARCH)/include/uapi \
 531                -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
 532                -I$(srctree)/include/uapi \
 533                -I$(objtree)/include/generated/uapi \
 534                -include $(srctree)/include/linux/compiler-version.h \
 535                -include $(srctree)/include/linux/kconfig.h
 536
 537# Use LINUXINCLUDE when you must reference the include/ directory.
 538# Needed to be compatible with the O= option
 539LINUXINCLUDE    := \
 540                -I$(srctree)/arch/$(SRCARCH)/include \
 541                -I$(objtree)/arch/$(SRCARCH)/include/generated \
 542                $(if $(building_out_of_srctree),-I$(srctree)/include) \
 543                -I$(objtree)/include \
 544                $(USERINCLUDE)
 545
 546KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
 547
 548KBUILD_CFLAGS :=
 549KBUILD_CFLAGS += -std=gnu11
 550KBUILD_CFLAGS += -fshort-wchar
 551KBUILD_CFLAGS += -funsigned-char
 552KBUILD_CFLAGS += -fno-common
 553KBUILD_CFLAGS += -fno-PIE
 554KBUILD_CFLAGS += -fno-strict-aliasing
 555
 556KBUILD_CPPFLAGS := -D__KERNEL__
 557KBUILD_RUSTFLAGS := $(rust_common_flags) \
 558                    --target=$(objtree)/scripts/target.json \
 559                    -Cpanic=abort -Cembed-bitcode=n -Clto=n \
 560                    -Cforce-unwind-tables=n -Ccodegen-units=1 \
 561                    -Csymbol-mangling-version=v0 \
 562                    -Crelocation-model=static \
 563                    -Zfunction-sections=n \
 564                    -Dclippy::float_arithmetic
 565
 566KBUILD_AFLAGS_KERNEL :=
 567KBUILD_CFLAGS_KERNEL :=
 568KBUILD_RUSTFLAGS_KERNEL :=
 569KBUILD_AFLAGS_MODULE  := -DMODULE
 570KBUILD_CFLAGS_MODULE  := -DMODULE
 571KBUILD_RUSTFLAGS_MODULE := --cfg MODULE
 572KBUILD_LDFLAGS_MODULE :=
 573KBUILD_LDFLAGS :=
 574CLANG_FLAGS :=
 575
 576ifeq ($(KBUILD_CLIPPY),1)
 577        RUSTC_OR_CLIPPY_QUIET := CLIPPY
 578        RUSTC_OR_CLIPPY = $(CLIPPY_DRIVER)
 579else
 580        RUSTC_OR_CLIPPY_QUIET := RUSTC
 581        RUSTC_OR_CLIPPY = $(RUSTC)
 582endif
 583
 584ifdef RUST_LIB_SRC
 585        export RUST_LIB_SRC
 586endif
 587
 588# Allows the usage of unstable features in stable compilers.
 589export RUSTC_BOOTSTRAP := 1
 590
 591export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG
 592export RUSTC RUSTDOC RUSTFMT RUSTC_OR_CLIPPY_QUIET RUSTC_OR_CLIPPY BINDGEN CARGO
 593export HOSTRUSTC KBUILD_HOSTRUSTFLAGS
 594export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
 595export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
 596export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
 597export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
 598export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS
 599
 600export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
 601export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
 602export KBUILD_RUSTFLAGS RUSTFLAGS_KERNEL RUSTFLAGS_MODULE
 603export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
 604export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_RUSTFLAGS_MODULE KBUILD_LDFLAGS_MODULE
 605export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL KBUILD_RUSTFLAGS_KERNEL
 606
 607# Files to ignore in find ... statements
 608
 609export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
 610                          -name CVS -o -name .pc -o -name .hg -o -name .git \) \
 611                          -prune -o
 612export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
 613                         --exclude CVS --exclude .pc --exclude .hg --exclude .git
 614
 615# ===========================================================================
 616# Rules shared between *config targets and build targets
 617
 618# Basic helpers built in scripts/basic/
 619PHONY += scripts_basic
 620scripts_basic:
 621        $(Q)$(MAKE) $(build)=scripts/basic
 622
 623PHONY += outputmakefile
 624ifdef building_out_of_srctree
 625# Before starting out-of-tree build, make sure the source tree is clean.
 626# outputmakefile generates a Makefile in the output directory, if using a
 627# separate output directory. This allows convenient use of make in the
 628# output directory.
 629# At the same time when output Makefile generated, generate .gitignore to
 630# ignore whole output directory
 631
 632quiet_cmd_makefile = GEN     Makefile
 633      cmd_makefile = { \
 634        echo "\# Automatically generated by $(srctree)/Makefile: don't edit"; \
 635        echo "include $(srctree)/Makefile"; \
 636        } > Makefile
 637
 638outputmakefile:
 639        @if [ -f $(srctree)/.config -o \
 640                 -d $(srctree)/include/config -o \
 641                 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
 642                echo >&2 "***"; \
 643                echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
 644                echo >&2 "*** in $(abs_srctree)";\
 645                echo >&2 "***"; \
 646                false; \
 647        fi
 648        $(Q)ln -fsn $(srctree) source
 649        $(call cmd,makefile)
 650        $(Q)test -e .gitignore || \
 651        { echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
 652endif
 653
 654# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
 655# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
 656# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
 657# and from include/config/auto.conf.cmd to detect the compiler upgrade.
 658CC_VERSION_TEXT = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1))
 659
 660ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
 661include $(srctree)/scripts/Makefile.clang
 662endif
 663
 664# Include this also for config targets because some architectures need
 665# cc-cross-prefix to determine CROSS_COMPILE.
 666ifdef need-compiler
 667include $(srctree)/scripts/Makefile.compiler
 668endif
 669
 670ifdef config-build
 671# ===========================================================================
 672# *config targets only - make sure prerequisites are updated, and descend
 673# in scripts/kconfig to make the *config target
 674
 675# Read arch-specific Makefile to set KBUILD_DEFCONFIG as needed.
 676# KBUILD_DEFCONFIG may point out an alternative default configuration
 677# used for 'make defconfig'
 678include $(srctree)/arch/$(SRCARCH)/Makefile
 679export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
 680
 681config: outputmakefile scripts_basic FORCE
 682        $(Q)$(MAKE) $(build)=scripts/kconfig $@
 683
 684%config: outputmakefile scripts_basic FORCE
 685        $(Q)$(MAKE) $(build)=scripts/kconfig $@
 686
 687else #!config-build
 688# ===========================================================================
 689# Build targets only - this includes vmlinux, arch-specific targets, clean
 690# targets and others. In general all targets except *config targets.
 691
 692# If building an external module we do not care about the all: rule
 693# but instead __all depend on modules
 694PHONY += all
 695ifeq ($(KBUILD_EXTMOD),)
 696__all: all
 697else
 698__all: modules
 699endif
 700
 701targets :=
 702
 703# Decide whether to build built-in, modular, or both.
 704# Normally, just do built-in.
 705
 706KBUILD_MODULES :=
 707KBUILD_BUILTIN := 1
 708
 709# If we have only "make modules", don't compile built-in objects.
 710ifeq ($(MAKECMDGOALS),modules)
 711  KBUILD_BUILTIN :=
 712endif
 713
 714# If we have "make <whatever> modules", compile modules
 715# in addition to whatever we do anyway.
 716# Just "make" or "make all" shall build modules as well
 717
 718ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
 719  KBUILD_MODULES := 1
 720endif
 721
 722ifeq ($(MAKECMDGOALS),)
 723  KBUILD_MODULES := 1
 724endif
 725
 726export KBUILD_MODULES KBUILD_BUILTIN
 727
 728ifdef need-config
 729include include/config/auto.conf
 730endif
 731
 732ifeq ($(KBUILD_EXTMOD),)
 733# Objects we will link into vmlinux / subdirs we need to visit
 734core-y          :=
 735drivers-y       :=
 736libs-y          := lib/
 737endif # KBUILD_EXTMOD
 738
 739# The all: target is the default when no target is given on the
 740# command line.
 741# This allow a user to issue only 'make' to build a kernel including modules
 742# Defaults to vmlinux, but the arch makefile usually adds further targets
 743all: vmlinux
 744
 745CFLAGS_GCOV     := -fprofile-arcs -ftest-coverage
 746ifdef CONFIG_CC_IS_GCC
 747CFLAGS_GCOV     += -fno-tree-loop-im
 748endif
 749export CFLAGS_GCOV
 750
 751# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
 752ifdef CONFIG_FUNCTION_TRACER
 753  CC_FLAGS_FTRACE := -pg
 754endif
 755
 756include $(srctree)/arch/$(SRCARCH)/Makefile
 757
 758ifdef need-config
 759ifdef may-sync-config
 760# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
 761# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
 762# because some architectures define CROSS_COMPILE there.
 763include include/config/auto.conf.cmd
 764
 765$(KCONFIG_CONFIG):
 766        @echo >&2 '***'
 767        @echo >&2 '*** Configuration file "$@" not found!'
 768        @echo >&2 '***'
 769        @echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
 770        @echo >&2 '*** "make menuconfig" or "make xconfig").'
 771        @echo >&2 '***'
 772        @/bin/false
 773
 774# The actual configuration files used during the build are stored in
 775# include/generated/ and include/config/. Update them if .config is newer than
 776# include/config/auto.conf (which mirrors .config).
 777#
 778# This exploits the 'multi-target pattern rule' trick.
 779# The syncconfig should be executed only once to make all the targets.
 780# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
 781#
 782# Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
 783# so you cannot notice that Kconfig is waiting for the user input.
 784%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h %/generated/rustc_cfg: $(KCONFIG_CONFIG)
 785        $(Q)$(kecho) "  SYNC    $@"
 786        $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
 787else # !may-sync-config
 788# External modules and some install targets need include/generated/autoconf.h
 789# and include/config/auto.conf but do not care if they are up-to-date.
 790# Use auto.conf to trigger the test
 791PHONY += include/config/auto.conf
 792
 793include/config/auto.conf:
 794        @test -e include/generated/autoconf.h -a -e $@ || (             \
 795        echo >&2;                                                       \
 796        echo >&2 "  ERROR: Kernel configuration is invalid.";           \
 797        echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
 798        echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";      \
 799        echo >&2 ;                                                      \
 800        /bin/false)
 801
 802endif # may-sync-config
 803endif # need-config
 804
 805KBUILD_CFLAGS   += -fno-delete-null-pointer-checks
 806
 807ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
 808KBUILD_CFLAGS += -O2
 809KBUILD_RUSTFLAGS += -Copt-level=2
 810else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
 811KBUILD_CFLAGS += -Os
 812KBUILD_RUSTFLAGS += -Copt-level=s
 813endif
 814
 815# Always set `debug-assertions` and `overflow-checks` because their default
 816# depends on `opt-level` and `debug-assertions`, respectively.
 817KBUILD_RUSTFLAGS += -Cdebug-assertions=$(if $(CONFIG_RUST_DEBUG_ASSERTIONS),y,n)
 818KBUILD_RUSTFLAGS += -Coverflow-checks=$(if $(CONFIG_RUST_OVERFLOW_CHECKS),y,n)
 819
 820# Tell gcc to never replace conditional load with a non-conditional one
 821ifdef CONFIG_CC_IS_GCC
 822# gcc-10 renamed --param=allow-store-data-races=0 to
 823# -fno-allow-store-data-races.
 824KBUILD_CFLAGS   += $(call cc-option,--param=allow-store-data-races=0)
 825KBUILD_CFLAGS   += $(call cc-option,-fno-allow-store-data-races)
 826endif
 827
 828ifdef CONFIG_READABLE_ASM
 829# Disable optimizations that make assembler listings hard to read.
 830# reorder blocks reorders the control in the function
 831# ipa clone creates specialized cloned functions
 832# partial inlining inlines only parts of functions
 833KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
 834endif
 835
 836stackp-flags-y                                    := -fno-stack-protector
 837stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
 838stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
 839
 840KBUILD_CFLAGS += $(stackp-flags-y)
 841
 842KBUILD_RUSTFLAGS-$(CONFIG_WERROR) += -Dwarnings
 843KBUILD_RUSTFLAGS += $(KBUILD_RUSTFLAGS-y)
 844
 845ifdef CONFIG_FRAME_POINTER
 846KBUILD_CFLAGS   += -fno-omit-frame-pointer -fno-optimize-sibling-calls
 847KBUILD_RUSTFLAGS += -Cforce-frame-pointers=y
 848else
 849# Some targets (ARM with Thumb2, for example), can't be built with frame
 850# pointers.  For those, we don't have FUNCTION_TRACER automatically
 851# select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
 852# incompatible with -fomit-frame-pointer with current GCC, so we don't use
 853# -fomit-frame-pointer with FUNCTION_TRACER.
 854# In the Rust target specification, "frame-pointer" is set explicitly
 855# to "may-omit".
 856ifndef CONFIG_FUNCTION_TRACER
 857KBUILD_CFLAGS   += -fomit-frame-pointer
 858endif
 859endif
 860
 861# Initialize all stack variables with a 0xAA pattern.
 862ifdef CONFIG_INIT_STACK_ALL_PATTERN
 863KBUILD_CFLAGS   += -ftrivial-auto-var-init=pattern
 864endif
 865
 866# Initialize all stack variables with a zero value.
 867ifdef CONFIG_INIT_STACK_ALL_ZERO
 868KBUILD_CFLAGS   += -ftrivial-auto-var-init=zero
 869ifdef CONFIG_CC_HAS_AUTO_VAR_INIT_ZERO_ENABLER
 870# https://github.com/llvm/llvm-project/issues/44842
 871CC_AUTO_VAR_INIT_ZERO_ENABLER := -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
 872export CC_AUTO_VAR_INIT_ZERO_ENABLER
 873KBUILD_CFLAGS   += $(CC_AUTO_VAR_INIT_ZERO_ENABLER)
 874endif
 875endif
 876
 877# While VLAs have been removed, GCC produces unreachable stack probes
 878# for the randomize_kstack_offset feature. Disable it for all compilers.
 879KBUILD_CFLAGS   += $(call cc-option, -fno-stack-clash-protection)
 880
 881# Clear used registers at func exit (to reduce data lifetime and ROP gadgets).
 882ifdef CONFIG_ZERO_CALL_USED_REGS
 883KBUILD_CFLAGS   += -fzero-call-used-regs=used-gpr
 884endif
 885
 886ifdef CONFIG_FUNCTION_TRACER
 887ifdef CONFIG_FTRACE_MCOUNT_USE_CC
 888  CC_FLAGS_FTRACE       += -mrecord-mcount
 889  ifdef CONFIG_HAVE_NOP_MCOUNT
 890    ifeq ($(call cc-option-yn, -mnop-mcount),y)
 891      CC_FLAGS_FTRACE   += -mnop-mcount
 892      CC_FLAGS_USING    += -DCC_USING_NOP_MCOUNT
 893    endif
 894  endif
 895endif
 896ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
 897  ifdef CONFIG_HAVE_OBJTOOL_NOP_MCOUNT
 898    CC_FLAGS_USING      += -DCC_USING_NOP_MCOUNT
 899  endif
 900endif
 901ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
 902  ifdef CONFIG_HAVE_C_RECORDMCOUNT
 903    BUILD_C_RECORDMCOUNT := y
 904    export BUILD_C_RECORDMCOUNT
 905  endif
 906endif
 907ifdef CONFIG_HAVE_FENTRY
 908  # s390-linux-gnu-gcc did not support -mfentry until gcc-9.
 909  ifeq ($(call cc-option-yn, -mfentry),y)
 910    CC_FLAGS_FTRACE     += -mfentry
 911    CC_FLAGS_USING      += -DCC_USING_FENTRY
 912  endif
 913endif
 914export CC_FLAGS_FTRACE
 915KBUILD_CFLAGS   += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
 916KBUILD_AFLAGS   += $(CC_FLAGS_USING)
 917endif
 918
 919# We trigger additional mismatches with less inlining
 920ifdef CONFIG_DEBUG_SECTION_MISMATCH
 921KBUILD_CFLAGS += -fno-inline-functions-called-once
 922endif
 923
 924# `rustc`'s `-Zfunction-sections` applies to data too (as of 1.59.0).
 925ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
 926KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
 927KBUILD_RUSTFLAGS_KERNEL += -Zfunction-sections=y
 928LDFLAGS_vmlinux += --gc-sections
 929endif
 930
 931ifdef CONFIG_SHADOW_CALL_STACK
 932ifndef CONFIG_DYNAMIC_SCS
 933CC_FLAGS_SCS    := -fsanitize=shadow-call-stack
 934KBUILD_CFLAGS   += $(CC_FLAGS_SCS)
 935endif
 936export CC_FLAGS_SCS
 937endif
 938
 939ifdef CONFIG_LTO_CLANG
 940ifdef CONFIG_LTO_CLANG_THIN
 941CC_FLAGS_LTO    := -flto=thin -fsplit-lto-unit
 942KBUILD_LDFLAGS  += --thinlto-cache-dir=$(extmod_prefix).thinlto-cache
 943else
 944CC_FLAGS_LTO    := -flto
 945endif
 946CC_FLAGS_LTO    += -fvisibility=hidden
 947
 948# Limit inlining across translation units to reduce binary size
 949KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
 950
 951# Check for frame size exceeding threshold during prolog/epilog insertion
 952# when using lld < 13.0.0.
 953ifneq ($(CONFIG_FRAME_WARN),0)
 954ifeq ($(call test-lt, $(CONFIG_LLD_VERSION), 130000),y)
 955KBUILD_LDFLAGS  += -plugin-opt=-warn-stack-size=$(CONFIG_FRAME_WARN)
 956endif
 957endif
 958endif
 959
 960ifdef CONFIG_LTO
 961KBUILD_CFLAGS   += -fno-lto $(CC_FLAGS_LTO)
 962KBUILD_AFLAGS   += -fno-lto
 963export CC_FLAGS_LTO
 964endif
 965
 966ifdef CONFIG_CFI_CLANG
 967CC_FLAGS_CFI    := -fsanitize=kcfi
 968KBUILD_CFLAGS   += $(CC_FLAGS_CFI)
 969export CC_FLAGS_CFI
 970endif
 971
 972ifneq ($(CONFIG_FUNCTION_ALIGNMENT),0)
 973KBUILD_CFLAGS += -falign-functions=$(CONFIG_FUNCTION_ALIGNMENT)
 974endif
 975
 976# arch Makefile may override CC so keep this after arch Makefile is included
 977NOSTDINC_FLAGS += -nostdinc
 978
 979# To gain proper coverage for CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE,
 980# the kernel uses only C99 flexible arrays for dynamically sized trailing
 981# arrays. Enforce this for everything that may examine structure sizes and
 982# perform bounds checking.
 983KBUILD_CFLAGS += $(call cc-option, -fstrict-flex-arrays=3)
 984
 985# disable invalid "can't wrap" optimizations for signed / pointers
 986KBUILD_CFLAGS   += -fno-strict-overflow
 987
 988# Make sure -fstack-check isn't enabled (like gentoo apparently did)
 989KBUILD_CFLAGS  += -fno-stack-check
 990
 991# conserve stack if available
 992ifdef CONFIG_CC_IS_GCC
 993KBUILD_CFLAGS   += -fconserve-stack
 994endif
 995
 996# change __FILE__ to the relative path from the srctree
 997KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
 998
 999# include additional Makefiles when needed
1000include-y                       := scripts/Makefile.extrawarn
1001include-$(CONFIG_DEBUG_INFO)    += scripts/Makefile.debug
1002include-$(CONFIG_DEBUG_INFO_BTF)+= scripts/Makefile.btf
1003include-$(CONFIG_KASAN)         += scripts/Makefile.kasan
1004include-$(CONFIG_KCSAN)         += scripts/Makefile.kcsan
1005include-$(CONFIG_KMSAN)         += scripts/Makefile.kmsan
1006include-$(CONFIG_UBSAN)         += scripts/Makefile.ubsan
1007include-$(CONFIG_KCOV)          += scripts/Makefile.kcov
1008include-$(CONFIG_RANDSTRUCT)    += scripts/Makefile.randstruct
1009include-$(CONFIG_GCC_PLUGINS)   += scripts/Makefile.gcc-plugins
1010
1011include $(addprefix $(srctree)/, $(include-y))
1012
1013# scripts/Makefile.gcc-plugins is intentionally included last.
1014# Do not add $(call cc-option,...) below this line. When you build the kernel
1015# from the clean source tree, the GCC plugins do not exist at this point.
1016
1017# Add user supplied CPPFLAGS, AFLAGS, CFLAGS and RUSTFLAGS as the last assignments
1018KBUILD_CPPFLAGS += $(KCPPFLAGS)
1019KBUILD_AFLAGS   += $(KAFLAGS)
1020KBUILD_CFLAGS   += $(KCFLAGS)
1021KBUILD_RUSTFLAGS += $(KRUSTFLAGS)
1022
1023KBUILD_LDFLAGS_MODULE += --build-id=sha1
1024LDFLAGS_vmlinux += --build-id=sha1
1025
1026KBUILD_LDFLAGS  += -z noexecstack
1027ifeq ($(CONFIG_LD_IS_BFD),y)
1028KBUILD_LDFLAGS  += $(call ld-option,--no-warn-rwx-segments)
1029endif
1030
1031ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1032LDFLAGS_vmlinux += -X
1033endif
1034
1035ifeq ($(CONFIG_RELR),y)
1036# ld.lld before 15 did not support -z pack-relative-relocs.
1037LDFLAGS_vmlinux += $(call ld-option,--pack-dyn-relocs=relr,-z pack-relative-relocs)
1038endif
1039
1040# We never want expected sections to be placed heuristically by the
1041# linker. All sections should be explicitly named in the linker script.
1042ifdef CONFIG_LD_ORPHAN_WARN
1043LDFLAGS_vmlinux += --orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL)
1044endif
1045
1046# Align the bit size of userspace programs with the kernel
1047KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1048KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1049
1050# make the checker run with the right architecture
1051CHECKFLAGS += --arch=$(ARCH)
1052
1053# insure the checker run with the right endianness
1054CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1055
1056# the checker needs the correct machine size
1057CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1058
1059# Default kernel image to build when no specific target is given.
1060# KBUILD_IMAGE may be overruled on the command line or
1061# set in the environment
1062# Also any assignments in arch/$(ARCH)/Makefile take precedence over
1063# this default value
1064export KBUILD_IMAGE ?= vmlinux
1065
1066#
1067# INSTALL_PATH specifies where to place the updated kernel and system map
1068# images. Default is /boot, but you can set it to other values
1069export  INSTALL_PATH ?= /boot
1070
1071#
1072# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1073# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1074# an argument if needed. Otherwise it defaults to the kernel install path
1075#
1076export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1077
1078#
1079# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1080# relocations required by build roots.  This is not defined in the
1081# makefile but the argument can be passed to make if needed.
1082#
1083
1084MODLIB  = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1085export MODLIB
1086
1087PHONY += prepare0
1088
1089export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
1090export MODORDER := $(extmod_prefix)modules.order
1091export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
1092
1093ifeq ($(KBUILD_EXTMOD),)
1094
1095build-dir       := .
1096clean-dirs      := $(sort . Documentation \
1097                     $(patsubst %/,%,$(filter %/, $(core-) \
1098                        $(drivers-) $(libs-))))
1099
1100export ARCH_CORE        := $(core-y)
1101export ARCH_LIB         := $(filter %/, $(libs-y))
1102export ARCH_DRIVERS     := $(drivers-y) $(drivers-m)
1103# Externally visible symbols (used by link-vmlinux.sh)
1104
1105KBUILD_VMLINUX_OBJS := ./built-in.a
1106ifdef CONFIG_MODULES
1107KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1108KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1109else
1110KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1111endif
1112
1113export KBUILD_VMLINUX_LIBS
1114export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1115
1116ifdef CONFIG_TRIM_UNUSED_KSYMS
1117# For the kernel to actually contain only the needed exported symbols,
1118# we have to build modules as well to determine what those symbols are.
1119KBUILD_MODULES := 1
1120endif
1121
1122# '$(AR) mPi' needs 'T' to workaround the bug of llvm-ar <= 14
1123quiet_cmd_ar_vmlinux.a = AR      $@
1124      cmd_ar_vmlinux.a = \
1125        rm -f $@; \
1126        $(AR) cDPrST $@ $(KBUILD_VMLINUX_OBJS); \
1127        $(AR) mPiT $$($(AR) t $@ | sed -n 1p) $@ $$($(AR) t $@ | grep -F -f $(srctree)/scripts/head-object-list.txt)
1128
1129targets += vmlinux.a
1130vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt FORCE
1131        $(call if_changed,ar_vmlinux.a)
1132
1133PHONY += vmlinux_o
1134vmlinux_o: vmlinux.a $(KBUILD_VMLINUX_LIBS)
1135        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o
1136
1137vmlinux.o modules.builtin.modinfo modules.builtin: vmlinux_o
1138        @:
1139
1140PHONY += vmlinux
1141# LDFLAGS_vmlinux in the top Makefile defines linker flags for the top vmlinux,
1142# not for decompressors. LDFLAGS_vmlinux in arch/*/boot/compressed/Makefile is
1143# unrelated; the decompressors just happen to have the same base name,
1144# arch/*/boot/compressed/vmlinux.
1145# Export LDFLAGS_vmlinux only to scripts/Makefile.vmlinux.
1146#
1147# _LDFLAGS_vmlinux is a workaround for the 'private export' bug:
1148#   https://savannah.gnu.org/bugs/?61463
1149# For Make > 4.4, the following simple code will work:
1150#  vmlinux: private export LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1151vmlinux: private _LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1152vmlinux: export LDFLAGS_vmlinux = $(_LDFLAGS_vmlinux)
1153vmlinux: vmlinux.o $(KBUILD_LDS) modpost
1154        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux
1155
1156# The actual objects are generated when descending,
1157# make sure no implicit rule kicks in
1158$(sort $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)): . ;
1159
1160ifeq ($(origin KERNELRELEASE),file)
1161filechk_kernel.release = $(srctree)/scripts/setlocalversion $(srctree)
1162else
1163filechk_kernel.release = echo $(KERNELRELEASE)
1164endif
1165
1166# Store (new) KERNELRELEASE string in include/config/kernel.release
1167include/config/kernel.release: FORCE
1168        $(call filechk,kernel.release)
1169
1170# Additional helpers built in scripts/
1171# Carefully list dependencies so we do not try to build scripts twice
1172# in parallel
1173PHONY += scripts
1174scripts: scripts_basic scripts_dtc
1175        $(Q)$(MAKE) $(build)=$(@)
1176
1177# Things we need to do before we recursively start building the kernel
1178# or the modules are listed in "prepare".
1179# A multi level approach is used. prepareN is processed before prepareN-1.
1180# archprepare is used in arch Makefiles and when processed asm symlink,
1181# version.h and scripts_basic is processed / created.
1182
1183PHONY += prepare archprepare
1184
1185archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1186        asm-generic $(version_h) include/generated/utsrelease.h \
1187        include/generated/compile.h include/generated/autoconf.h remove-stale-files
1188
1189prepare0: archprepare
1190        $(Q)$(MAKE) $(build)=scripts/mod
1191        $(Q)$(MAKE) $(build)=. prepare
1192
1193# All the preparing..
1194prepare: prepare0
1195ifdef CONFIG_RUST
1196        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh
1197        $(Q)$(MAKE) $(build)=rust
1198endif
1199
1200PHONY += remove-stale-files
1201remove-stale-files:
1202        $(Q)$(srctree)/scripts/remove-stale-files
1203
1204# Support for using generic headers in asm-generic
1205asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1206
1207PHONY += asm-generic uapi-asm-generic
1208asm-generic: uapi-asm-generic
1209        $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1210        generic=include/asm-generic
1211uapi-asm-generic:
1212        $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1213        generic=include/uapi/asm-generic
1214
1215# Generate some files
1216# ---------------------------------------------------------------------------
1217
1218# KERNELRELEASE can change from a few different places, meaning version.h
1219# needs to be updated, so this check is forced on all builds
1220
1221uts_len := 64
1222define filechk_utsrelease.h
1223        if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1224          echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1225          exit 1;                                                         \
1226        fi;                                                               \
1227        echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1228endef
1229
1230define filechk_version.h
1231        if [ $(SUBLEVEL) -gt 255 ]; then                                 \
1232                echo \#define LINUX_VERSION_CODE $(shell                 \
1233                expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1234        else                                                             \
1235                echo \#define LINUX_VERSION_CODE $(shell                 \
1236                expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1237        fi;                                                              \
1238        echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
1239        ((c) > 255 ? 255 : (c)))';                                       \
1240        echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
1241        echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
1242        echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1243endef
1244
1245$(version_h): PATCHLEVEL := $(or $(PATCHLEVEL), 0)
1246$(version_h): SUBLEVEL := $(or $(SUBLEVEL), 0)
1247$(version_h): FORCE
1248        $(call filechk,version.h)
1249
1250include/generated/utsrelease.h: include/config/kernel.release FORCE
1251        $(call filechk,utsrelease.h)
1252
1253filechk_compile.h = $(srctree)/scripts/mkcompile_h \
1254        "$(UTS_MACHINE)" "$(CONFIG_CC_VERSION_TEXT)" "$(LD)"
1255
1256include/generated/compile.h: FORCE
1257        $(call filechk,compile.h)
1258
1259PHONY += headerdep
1260headerdep:
1261        $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1262        $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1263
1264# ---------------------------------------------------------------------------
1265# Kernel headers
1266
1267#Default location for installed headers
1268export INSTALL_HDR_PATH = $(objtree)/usr
1269
1270quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1271      cmd_headers_install = \
1272        mkdir -p $(INSTALL_HDR_PATH); \
1273        rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1274        usr/include $(INSTALL_HDR_PATH)
1275
1276PHONY += headers_install
1277headers_install: headers
1278        $(call cmd,headers_install)
1279
1280PHONY += archheaders archscripts
1281
1282hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1283
1284PHONY += headers
1285headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1286        $(if $(filter um, $(SRCARCH)), $(error Headers not exportable for UML))
1287        $(Q)$(MAKE) $(hdr-inst)=include/uapi
1288        $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1289
1290ifdef CONFIG_HEADERS_INSTALL
1291prepare: headers
1292endif
1293
1294PHONY += scripts_unifdef
1295scripts_unifdef: scripts_basic
1296        $(Q)$(MAKE) $(build)=scripts scripts/unifdef
1297
1298# ---------------------------------------------------------------------------
1299# Install
1300
1301# Many distributions have the custom install script, /sbin/installkernel.
1302# If DKMS is installed, 'make install' will eventually recurse back
1303# to this Makefile to build and install external modules.
1304# Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
1305
1306quiet_cmd_install = INSTALL $(INSTALL_PATH)
1307      cmd_install = unset sub_make_done; $(srctree)/scripts/install.sh
1308
1309# ---------------------------------------------------------------------------
1310# vDSO install
1311
1312PHONY += vdso_install
1313vdso_install: export INSTALL_FILES = $(vdso-install-y)
1314vdso_install:
1315        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vdsoinst
1316
1317# ---------------------------------------------------------------------------
1318# Tools
1319
1320ifdef CONFIG_OBJTOOL
1321prepare: tools/objtool
1322endif
1323
1324ifdef CONFIG_BPF
1325ifdef CONFIG_DEBUG_INFO_BTF
1326prepare: tools/bpf/resolve_btfids
1327endif
1328endif
1329
1330PHONY += resolve_btfids_clean
1331
1332resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1333
1334# tools/bpf/resolve_btfids directory might not exist
1335# in output directory, skip its clean in that case
1336resolve_btfids_clean:
1337ifneq ($(wildcard $(resolve_btfids_O)),)
1338        $(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1339endif
1340
1341# Clear a bunch of variables before executing the submake
1342ifeq ($(quiet),silent_)
1343tools_silent=s
1344endif
1345
1346tools/: FORCE
1347        $(Q)mkdir -p $(objtree)/tools
1348        $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1349
1350tools/%: FORCE
1351        $(Q)mkdir -p $(objtree)/tools
1352        $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1353
1354# ---------------------------------------------------------------------------
1355# Kernel selftest
1356
1357PHONY += kselftest
1358kselftest: headers
1359        $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1360
1361kselftest-%: headers FORCE
1362        $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1363
1364PHONY += kselftest-merge
1365kselftest-merge:
1366        $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1367        $(Q)find $(srctree)/tools/testing/selftests -name config -o -name config.$(UTS_MACHINE) | \
1368                xargs $(srctree)/scripts/kconfig/merge_config.sh -y -m $(objtree)/.config
1369        $(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1370
1371# ---------------------------------------------------------------------------
1372# Devicetree files
1373
1374ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1375dtstree := arch/$(SRCARCH)/boot/dts
1376endif
1377
1378ifneq ($(dtstree),)
1379
1380%.dtb: dtbs_prepare
1381        $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1382
1383%.dtbo: dtbs_prepare
1384        $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1385
1386PHONY += dtbs dtbs_prepare dtbs_install dtbs_check
1387dtbs: dtbs_prepare
1388        $(Q)$(MAKE) $(build)=$(dtstree)
1389
1390# include/config/kernel.release is actually needed when installing DTBs because
1391# INSTALL_DTBS_PATH contains $(KERNELRELEASE). However, we do not want to make
1392# dtbs_install depend on it as dtbs_install may run as root.
1393dtbs_prepare: include/config/kernel.release scripts_dtc
1394
1395ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1396export CHECK_DTBS=y
1397endif
1398
1399ifneq ($(CHECK_DTBS),)
1400dtbs_prepare: dt_binding_check
1401endif
1402
1403dtbs_check: dtbs
1404
1405dtbs_install:
1406        $(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1407
1408ifdef CONFIG_OF_EARLY_FLATTREE
1409all: dtbs
1410endif
1411
1412endif
1413
1414PHONY += scripts_dtc
1415scripts_dtc: scripts_basic
1416        $(Q)$(MAKE) $(build)=scripts/dtc
1417
1418ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1419export CHECK_DT_BINDING=y
1420endif
1421
1422PHONY += dt_binding_check
1423dt_binding_check: scripts_dtc
1424        $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1425
1426PHONY += dt_compatible_check
1427dt_compatible_check: dt_binding_check
1428        $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1429
1430# ---------------------------------------------------------------------------
1431# Modules
1432
1433ifdef CONFIG_MODULES
1434
1435# By default, build modules as well
1436
1437all: modules
1438
1439# When we're building modules with modversions, we need to consider
1440# the built-in objects during the descend as well, in order to
1441# make sure the checksums are up to date before we record them.
1442ifdef CONFIG_MODVERSIONS
1443  KBUILD_BUILTIN := 1
1444endif
1445
1446# Build modules
1447#
1448
1449# *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFO_BTF_MODULES
1450# is an exception.
1451ifdef CONFIG_DEBUG_INFO_BTF_MODULES
1452KBUILD_BUILTIN := 1
1453modules: vmlinux
1454endif
1455
1456modules: modules_prepare
1457
1458# Target to prepare building external modules
1459modules_prepare: prepare
1460        $(Q)$(MAKE) $(build)=scripts scripts/module.lds
1461
1462endif # CONFIG_MODULES
1463
1464###
1465# Cleaning is done on three levels.
1466# make clean     Delete most generated files
1467#                Leave enough to build external modules
1468# make mrproper  Delete the current configuration, and all generated files
1469# make distclean Remove editor backup files, patch leftover files and the like
1470
1471# Directories & files removed with 'make clean'
1472CLEAN_FILES += vmlinux.symvers modules-only.symvers \
1473               modules.builtin modules.builtin.modinfo modules.nsdeps \
1474               compile_commands.json .thinlto-cache rust/test \
1475               rust-project.json .vmlinux.objs .vmlinux.export.c
1476
1477# Directories & files removed with 'make mrproper'
1478MRPROPER_FILES += include/config include/generated          \
1479                  arch/$(SRCARCH)/include/generated .objdiff \
1480                  debian snap tar-install \
1481                  .config .config.old .version \
1482                  Module.symvers \
1483                  certs/signing_key.pem \
1484                  certs/x509.genkey \
1485                  vmlinux-gdb.py \
1486                  rpmbuild \
1487                  rust/libmacros.so
1488
1489# clean - Delete most, but leave enough to build external modules
1490#
1491clean: rm-files := $(CLEAN_FILES)
1492
1493PHONY += archclean vmlinuxclean
1494
1495vmlinuxclean:
1496        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1497        $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1498
1499clean: archclean vmlinuxclean resolve_btfids_clean
1500
1501# mrproper - Delete all generated files, including .config
1502#
1503mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1504mrproper-dirs      := $(addprefix _mrproper_,scripts)
1505
1506PHONY += $(mrproper-dirs) mrproper
1507$(mrproper-dirs):
1508        $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1509
1510mrproper: clean $(mrproper-dirs)
1511        $(call cmd,rmfiles)
1512        @find . $(RCS_FIND_IGNORE) \
1513                \( -name '*.rmeta' \) \
1514                -type f -print | xargs rm -f
1515
1516# distclean
1517#
1518PHONY += distclean
1519
1520distclean: mrproper
1521        @find . $(RCS_FIND_IGNORE) \
1522                \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1523                -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1524                -o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1525                -o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1526                -type f -print | xargs rm -f
1527
1528
1529# Packaging of the kernel to various formats
1530# ---------------------------------------------------------------------------
1531
1532%src-pkg: FORCE
1533        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1534%pkg: include/config/kernel.release FORCE
1535        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1536
1537# Brief documentation of the typical targets used
1538# ---------------------------------------------------------------------------
1539
1540boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1541boards := $(sort $(notdir $(boards)))
1542board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1543board-dirs := $(sort $(notdir $(board-dirs:/=)))
1544
1545PHONY += help
1546help:
1547        @echo  'Cleaning targets:'
1548        @echo  '  clean           - Remove most generated files but keep the config and'
1549        @echo  '                    enough build support to build external modules'
1550        @echo  '  mrproper        - Remove all generated files + config + various backup files'
1551        @echo  '  distclean       - mrproper + remove editor backup and patch files'
1552        @echo  ''
1553        @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1554        @echo  ''
1555        @echo  'Other generic targets:'
1556        @echo  '  all             - Build all targets marked with [*]'
1557        @echo  '* vmlinux         - Build the bare kernel'
1558        @echo  '* modules         - Build all modules'
1559        @echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1560        @echo  '  vdso_install    - Install unstripped vdso to INSTALL_MOD_PATH (default: /)'
1561        @echo  '  dir/            - Build all files in dir and below'
1562        @echo  '  dir/file.[ois]  - Build specified target only'
1563        @echo  '  dir/file.ll     - Build the LLVM assembly file'
1564        @echo  '                    (requires compiler support for LLVM assembly generation)'
1565        @echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1566        @echo  '                    (requires a recent binutils and recent build (System.map))'
1567        @echo  '  dir/file.ko     - Build module including final link'
1568        @echo  '  modules_prepare - Set up for building external modules'
1569        @echo  '  tags/TAGS       - Generate tags file for editors'
1570        @echo  '  cscope          - Generate cscope index'
1571        @echo  '  gtags           - Generate GNU GLOBAL index'
1572        @echo  '  kernelrelease   - Output the release version string (use with make -s)'
1573        @echo  '  kernelversion   - Output the version stored in Makefile (use with make -s)'
1574        @echo  '  image_name      - Output the image name (use with make -s)'
1575        @echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1576         echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1577         echo  ''
1578        @echo  'Static analysers:'
1579        @echo  '  checkstack      - Generate a list of stack hogs'
1580        @echo  '  versioncheck    - Sanity check on version.h usage'
1581        @echo  '  includecheck    - Check for duplicate included header files'
1582        @echo  '  export_report   - List the usages of all exported symbols'
1583        @echo  '  headerdep       - Detect inclusion cycles in headers'
1584        @echo  '  coccicheck      - Check with Coccinelle'
1585        @echo  '  clang-analyzer  - Check with clang static analyzer'
1586        @echo  '  clang-tidy      - Check with clang-tidy'
1587        @echo  ''
1588        @echo  'Tools:'
1589        @echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1590        @echo  ''
1591        @echo  'Kernel selftest:'
1592        @echo  '  kselftest         - Build and run kernel selftest'
1593        @echo  '                      Build, install, and boot kernel before'
1594        @echo  '                      running kselftest on it'
1595        @echo  '                      Run as root for full coverage'
1596        @echo  '  kselftest-all     - Build kernel selftest'
1597        @echo  '  kselftest-install - Build and install kernel selftest'
1598        @echo  '  kselftest-clean   - Remove all generated kselftest files'
1599        @echo  '  kselftest-merge   - Merge all the config dependencies of'
1600        @echo  '                      kselftest to existing .config.'
1601        @echo  ''
1602        @echo  'Rust targets:'
1603        @echo  '  rustavailable   - Checks whether the Rust toolchain is'
1604        @echo  '                    available and, if not, explains why.'
1605        @echo  '  rustfmt         - Reformat all the Rust code in the kernel'
1606        @echo  '  rustfmtcheck    - Checks if all the Rust code in the kernel'
1607        @echo  '                    is formatted, printing a diff otherwise.'
1608        @echo  '  rustdoc         - Generate Rust documentation'
1609        @echo  '                    (requires kernel .config)'
1610        @echo  '  rusttest        - Runs the Rust tests'
1611        @echo  '                    (requires kernel .config; downloads external repos)'
1612        @echo  '  rust-analyzer   - Generate rust-project.json rust-analyzer support file'
1613        @echo  '                    (requires kernel .config)'
1614        @echo  '  dir/file.[os]   - Build specified target only'
1615        @echo  '  dir/file.rsi    - Build macro expanded source, similar to C preprocessing.'
1616        @echo  '                    Run with RUSTFMT=n to skip reformatting if needed.'
1617        @echo  '                    The output is not intended to be compilable.'
1618        @echo  '  dir/file.ll     - Build the LLVM assembly file'
1619        @echo  ''
1620        @$(if $(dtstree), \
1621                echo 'Devicetree:'; \
1622                echo '* dtbs             - Build device tree blobs for enabled boards'; \
1623                echo '  dtbs_install     - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1624                echo '  dt_binding_check - Validate device tree binding documents'; \
1625                echo '  dtbs_check       - Validate device tree source files';\
1626                echo '')
1627
1628        @echo 'Userspace tools targets:'
1629        @echo '  use "make tools/help"'
1630        @echo '  or  "cd tools; make help"'
1631        @echo  ''
1632        @echo  'Kernel packaging:'
1633        @$(MAKE) -f $(srctree)/scripts/Makefile.package help
1634        @echo  ''
1635        @echo  'Documentation targets:'
1636        @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1637        @echo  ''
1638        @echo  'Architecture-specific targets ($(SRCARCH)):'
1639        @$(or $(archhelp),\
1640                echo '  No architecture-specific help defined for $(SRCARCH)')
1641        @echo  ''
1642        @$(if $(boards), \
1643                $(foreach b, $(boards), \
1644                printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1645                echo '')
1646        @$(if $(board-dirs), \
1647                $(foreach b, $(board-dirs), \
1648                printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1649                printf "  %-16s - Show all of the above\\n" help-boards; \
1650                echo '')
1651
1652        @echo  '  make V=n   [targets] 1: verbose build'
1653        @echo  '                       2: give reason for rebuild of target'
1654        @echo  '                       V=1 and V=2 can be combined with V=12'
1655        @echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1656        @echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1657        @echo  '                       (sparse by default)'
1658        @echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1659        @echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1660        @echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
1661        @echo  '                1: warnings which may be relevant and do not occur too often'
1662        @echo  '                2: warnings which occur quite often but may still be relevant'
1663        @echo  '                3: more obscure warnings, can most likely be ignored'
1664        @echo  '                e: warnings are being treated as errors'
1665        @echo  '                Multiple levels can be combined with W=12 or W=123'
1666        @$(if $(dtstree), \
1667                echo '  make CHECK_DTBS=1 [targets] Check all generated dtb files against schema'; \
1668                echo '         This can be applied both to "dtbs" and to individual "foo.dtb" targets' ; \
1669                )
1670        @echo  ''
1671        @echo  'Execute "make" or "make all" to build all targets marked with [*] '
1672        @echo  'For further info see the ./README file'
1673
1674
1675help-board-dirs := $(addprefix help-,$(board-dirs))
1676
1677help-boards: $(help-board-dirs)
1678
1679boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1680
1681$(help-board-dirs): help-%:
1682        @echo  'Architecture-specific targets ($(SRCARCH) $*):'
1683        @$(if $(boards-per-dir), \
1684                $(foreach b, $(boards-per-dir), \
1685                printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1686                echo '')
1687
1688
1689# Documentation targets
1690# ---------------------------------------------------------------------------
1691DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1692               linkcheckdocs dochelp refcheckdocs texinfodocs infodocs
1693PHONY += $(DOC_TARGETS)
1694$(DOC_TARGETS):
1695        $(Q)$(MAKE) $(build)=Documentation $@
1696
1697
1698# Rust targets
1699# ---------------------------------------------------------------------------
1700
1701# "Is Rust available?" target
1702PHONY += rustavailable
1703rustavailable:
1704        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh && echo "Rust is available!"
1705
1706# Documentation target
1707#
1708# Using the singular to avoid running afoul of `no-dot-config-targets`.
1709PHONY += rustdoc
1710rustdoc: prepare
1711        $(Q)$(MAKE) $(build)=rust $@
1712
1713# Testing target
1714PHONY += rusttest
1715rusttest: prepare
1716        $(Q)$(MAKE) $(build)=rust $@
1717
1718# Formatting targets
1719PHONY += rustfmt rustfmtcheck
1720
1721# We skip `rust/alloc` since we want to minimize the diff w.r.t. upstream.
1722#
1723# We match using absolute paths since `find` does not resolve them
1724# when matching, which is a problem when e.g. `srctree` is `..`.
1725# We `grep` afterwards in order to remove the directory entry itself.
1726rustfmt:
1727        $(Q)find $(abs_srctree) -type f -name '*.rs' \
1728                -o -path $(abs_srctree)/rust/alloc -prune \
1729                -o -path $(abs_objtree)/rust/test -prune \
1730                | grep -Fv $(abs_srctree)/rust/alloc \
1731                | grep -Fv $(abs_objtree)/rust/test \
1732                | grep -Fv generated \
1733                | xargs $(RUSTFMT) $(rustfmt_flags)
1734
1735rustfmtcheck: rustfmt_flags = --check
1736rustfmtcheck: rustfmt
1737
1738# Misc
1739# ---------------------------------------------------------------------------
1740
1741PHONY += misc-check
1742misc-check:
1743        $(Q)$(srctree)/scripts/misc-check
1744
1745all: misc-check
1746
1747PHONY += scripts_gdb
1748scripts_gdb: prepare0
1749        $(Q)$(MAKE) $(build)=scripts/gdb
1750        $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1751
1752ifdef CONFIG_GDB_SCRIPTS
1753all: scripts_gdb
1754endif
1755
1756else # KBUILD_EXTMOD
1757
1758filechk_kernel.release = echo $(KERNELRELEASE)
1759
1760###
1761# External module support.
1762# When building external modules the kernel used as basis is considered
1763# read-only, and no consistency checks are made and the make
1764# system is not used on the basis kernel. If updates are required
1765# in the basis kernel ordinary make commands (without M=...) must be used.
1766
1767# We are always building only modules.
1768KBUILD_BUILTIN :=
1769KBUILD_MODULES := 1
1770
1771build-dir := $(KBUILD_EXTMOD)
1772
1773compile_commands.json: $(extmod_prefix)compile_commands.json
1774PHONY += compile_commands.json
1775
1776clean-dirs := $(KBUILD_EXTMOD)
1777clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1778        $(KBUILD_EXTMOD)/compile_commands.json $(KBUILD_EXTMOD)/.thinlto-cache
1779
1780PHONY += prepare
1781# now expand this into a simple variable to reduce the cost of shell evaluations
1782prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT)
1783prepare:
1784        @if [ "$(CC_VERSION_TEXT)" != "$(CONFIG_CC_VERSION_TEXT)" ]; then \
1785                echo >&2 "warning: the compiler differs from the one used to build the kernel"; \
1786                echo >&2 "  The kernel was built by: $(CONFIG_CC_VERSION_TEXT)"; \
1787                echo >&2 "  You are using:           $(CC_VERSION_TEXT)"; \
1788        fi
1789
1790PHONY += help
1791help:
1792        @echo  '  Building external modules.'
1793        @echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1794        @echo  ''
1795        @echo  '  modules         - default target, build the module(s)'
1796        @echo  '  modules_install - install the module'
1797        @echo  '  clean           - remove generated files in module directory only'
1798        @echo  '  rust-analyzer   - generate rust-project.json rust-analyzer support file'
1799        @echo  ''
1800
1801ifndef CONFIG_MODULES
1802modules modules_install: __external_modules_error
1803__external_modules_error:
1804        @echo >&2 '***'
1805        @echo >&2 '*** The present kernel disabled CONFIG_MODULES.'
1806        @echo >&2 '*** You cannot build or install external modules.'
1807        @echo >&2 '***'
1808        @false
1809endif
1810
1811endif # KBUILD_EXTMOD
1812
1813# ---------------------------------------------------------------------------
1814# Modules
1815
1816PHONY += modules modules_install modules_sign modules_prepare
1817
1818modules_install:
1819        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst \
1820        sign-only=$(if $(filter modules_install,$(MAKECMDGOALS)),,y)
1821
1822ifeq ($(CONFIG_MODULE_SIG),y)
1823# modules_sign is a subset of modules_install.
1824# 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1825modules_sign: modules_install
1826        @:
1827else
1828modules_sign:
1829        @echo >&2 '***'
1830        @echo >&2 '*** CONFIG_MODULE_SIG is disabled. You cannot sign modules.'
1831        @echo >&2 '***'
1832        @false
1833endif
1834
1835ifdef CONFIG_MODULES
1836
1837$(MODORDER): $(build-dir)
1838        @:
1839
1840# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
1841# This is solely useful to speed up test compiles.
1842modules: modpost
1843ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1844        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1845endif
1846
1847PHONY += modules_check
1848modules_check: $(MODORDER)
1849        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1850
1851else # CONFIG_MODULES
1852
1853modules:
1854        @:
1855
1856KBUILD_MODULES :=
1857
1858endif # CONFIG_MODULES
1859
1860PHONY += modpost
1861modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \
1862         $(if $(KBUILD_MODULES), modules_check)
1863        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1864
1865# Single targets
1866# ---------------------------------------------------------------------------
1867# To build individual files in subdirectories, you can do like this:
1868#
1869#   make foo/bar/baz.s
1870#
1871# The supported suffixes for single-target are listed in 'single-targets'
1872#
1873# To build only under specific subdirectories, you can do like this:
1874#
1875#   make foo/bar/baz/
1876
1877ifdef single-build
1878
1879# .ko is special because modpost is needed
1880single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1881single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \
1882                $(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko)))
1883
1884$(single-ko): single_modules
1885        @:
1886$(single-no-ko): $(build-dir)
1887        @:
1888
1889# Remove MODORDER when done because it is not the real one.
1890PHONY += single_modules
1891single_modules: $(single-no-ko) modules_prepare
1892        $(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$(m:%.ko=%.o);) } > $(MODORDER)
1893        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1894ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1895        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1896endif
1897        $(Q)rm -f $(MODORDER)
1898
1899single-goals := $(addprefix $(build-dir)/, $(single-no-ko))
1900
1901KBUILD_MODULES := 1
1902
1903endif
1904
1905# Preset locale variables to speed up the build process. Limit locale
1906# tweaks to this spot to avoid wrong language settings when running
1907# make menuconfig etc.
1908# Error messages still appears in the original language
1909PHONY += $(build-dir)
1910$(build-dir): prepare
1911        $(Q)$(MAKE) $(build)=$@ need-builtin=1 need-modorder=1 $(single-goals)
1912
1913clean-dirs := $(addprefix _clean_, $(clean-dirs))
1914PHONY += $(clean-dirs) clean
1915$(clean-dirs):
1916        $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1917
1918clean: $(clean-dirs)
1919        $(call cmd,rmfiles)
1920        @find $(or $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1921                \( -name '*.[aios]' -o -name '*.rsi' -o -name '*.ko' -o -name '.*.cmd' \
1922                -o -name '*.ko.*' \
1923                -o -name '*.dtb' -o -name '*.dtbo' \
1924                -o -name '*.dtb.S' -o -name '*.dtbo.S' \
1925                -o -name '*.dt.yaml' \
1926                -o -name '*.dwo' -o -name '*.lst' \
1927                -o -name '*.su' -o -name '*.mod' \
1928                -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1929                -o -name '*.lex.c' -o -name '*.tab.[ch]' \
1930                -o -name '*.asn1.[ch]' \
1931                -o -name '*.symtypes' -o -name 'modules.order' \
1932                -o -name '*.c.[012]*.*' \
1933                -o -name '*.ll' \
1934                -o -name '*.gcno' \
1935                -o -name '*.*.symversions' \) -type f -print \
1936                -o -name '.tmp_*' -print \
1937                | xargs rm -rf
1938
1939# Generate tags for editors
1940# ---------------------------------------------------------------------------
1941quiet_cmd_tags = GEN     $@
1942      cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1943
1944tags TAGS cscope gtags: FORCE
1945        $(call cmd,tags)
1946
1947# IDE support targets
1948PHONY += rust-analyzer
1949rust-analyzer:
1950        $(Q)$(MAKE) $(build)=rust $@
1951
1952# Script to generate missing namespace dependencies
1953# ---------------------------------------------------------------------------
1954
1955PHONY += nsdeps
1956nsdeps: export KBUILD_NSDEPS=1
1957nsdeps: modules
1958        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1959
1960# Clang Tooling
1961# ---------------------------------------------------------------------------
1962
1963quiet_cmd_gen_compile_commands = GEN     $@
1964      cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
1965
1966$(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
1967        $(if $(KBUILD_EXTMOD),, vmlinux.a $(KBUILD_VMLINUX_LIBS)) \
1968        $(if $(CONFIG_MODULES), $(MODORDER)) FORCE
1969        $(call if_changed,gen_compile_commands)
1970
1971targets += $(extmod_prefix)compile_commands.json
1972
1973PHONY += clang-tidy clang-analyzer
1974
1975ifdef CONFIG_CC_IS_CLANG
1976quiet_cmd_clang_tools = CHECK   $<
1977      cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
1978
1979clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
1980        $(call cmd,clang_tools)
1981else
1982clang-tidy clang-analyzer:
1983        @echo "$@ requires CC=clang" >&2
1984        @false
1985endif
1986
1987# Scripts to check various things for consistency
1988# ---------------------------------------------------------------------------
1989
1990PHONY += includecheck versioncheck coccicheck export_report
1991
1992includecheck:
1993        find $(srctree)/* $(RCS_FIND_IGNORE) \
1994                -name '*.[hcS]' -type f -print | sort \
1995                | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1996
1997versioncheck:
1998        find $(srctree)/* $(RCS_FIND_IGNORE) \
1999                -name '*.[hcS]' -type f -print | sort \
2000                | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
2001
2002coccicheck:
2003        $(Q)$(BASH) $(srctree)/scripts/$@
2004
2005export_report:
2006        $(PERL) $(srctree)/scripts/export_report.pl
2007
2008PHONY += checkstack kernelrelease kernelversion image_name
2009
2010# UML needs a little special treatment here.  It wants to use the host
2011# toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
2012# else wants $(ARCH), including people doing cross-builds, which means
2013# that $(SUBARCH) doesn't work here.
2014ifeq ($(ARCH), um)
2015CHECKSTACK_ARCH := $(SUBARCH)
2016else
2017CHECKSTACK_ARCH := $(ARCH)
2018endif
2019checkstack:
2020        $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
2021        $(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
2022
2023kernelrelease:
2024        @$(filechk_kernel.release)
2025
2026kernelversion:
2027        @echo $(KERNELVERSION)
2028
2029image_name:
2030        @echo $(KBUILD_IMAGE)
2031
2032PHONY += run-command
2033run-command:
2034        $(Q)$(KBUILD_RUN_COMMAND)
2035
2036quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
2037      cmd_rmfiles = rm -rf $(rm-files)
2038
2039# read saved command lines for existing targets
2040existing-targets := $(wildcard $(sort $(targets)))
2041
2042-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
2043
2044endif # config-build
2045endif # mixed-build
2046endif # need-sub-make
2047
2048PHONY += FORCE
2049FORCE:
2050
2051# Declare the contents of the PHONY variable as phony.  We keep that
2052# information in a variable so we can use it in if_changed and friends.
2053.PHONY: $(PHONY)
2054