1# SPDX-License-Identifier: GPL-2.0 2VERSION = 6 3PATCHLEVEL = 3 4SUBLEVEL = 0 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 $(error targets prefixed with '__' are only for internal use)) 20 21# That's our default target when none is given on the command line 22PHONY := __all 23__all: 24 25# We are using a recursive build, so we need to do a little thinking 26# to get the ordering right. 27# 28# Most importantly: sub-Makefiles should only ever modify files in 29# their own directory. If in some directory we have a dependency on 30# a file in another dir (which doesn't happen often, but it's often 31# unavoidable when linking the built-in.a targets which finally 32# turn into vmlinux), we will call a sub make in that other dir, and 33# after that we are sure that everything which is in that other dir 34# is now up to date. 35# 36# The only cases where we need to modify files which have global 37# effects are thus separated out and done before the recursive 38# descending is started. They are now explicitly listed as the 39# prepare rule. 40 41ifneq ($(sub_make_done),1) 42 43# Do not use make's built-in rules and variables 44# (this increases performance and avoids hard-to-debug behaviour) 45MAKEFLAGS += -rR 46 47# Avoid funny character set dependencies 48unexport LC_ALL 49LC_COLLATE=C 50LC_NUMERIC=C 51export LC_COLLATE LC_NUMERIC 52 53# Avoid interference with shell env settings 54unexport GREP_OPTIONS 55 56# Beautify output 57# --------------------------------------------------------------------------- 58# 59# Most of build commands in Kbuild start with "cmd_". You can optionally define 60# "quiet_cmd_*". If defined, the short log is printed. Otherwise, no log from 61# that command is printed by default. 62# 63# e.g.) 64# quiet_cmd_depmod = DEPMOD $(MODLIB) 65# cmd_depmod = $(srctree)/scripts/depmod.sh $(DEPMOD) $(KERNELRELEASE) 66# 67# A simple variant is to prefix commands with $(Q) - that's useful 68# for commands that shall be hidden in non-verbose mode. 69# 70# $(Q)$(MAKE) $(build)=scripts/basic 71# 72# If KBUILD_VERBOSE contains 1, the whole command is echoed. 73# If KBUILD_VERBOSE contains 2, the reason for rebuilding is printed. 74# 75# To put more focus on warnings, be less verbose as default 76# Use 'make V=1' to see the full commands 77 78ifeq ("$(origin V)", "command line") 79 KBUILD_VERBOSE = $(V) 80endif 81 82quiet = quiet_ 83Q = @ 84 85ifneq ($(findstring 1, $(KBUILD_VERBOSE)),) 86 quiet = 87 Q = 88endif 89 90# If the user is running make -s (silent mode), suppress echoing of 91# commands 92# make-4.0 (and later) keep single letter options in the 1st word of MAKEFLAGS. 93 94ifeq ($(filter 3.%,$(MAKE_VERSION)),) 95short-opts := $(firstword -$(MAKEFLAGS)) 96else 97short-opts := $(filter-out --%,$(MAKEFLAGS)) 98endif 99 100ifneq ($(findstring s,$(short-opts)),) 101quiet=silent_ 102override KBUILD_VERBOSE := 103endif 104 105export quiet Q KBUILD_VERBOSE 106 107# Call a source code checker (by default, "sparse") as part of the 108# C compilation. 109# 110# Use 'make C=1' to enable checking of only re-compiled files. 111# Use 'make C=2' to enable checking of *all* source files, regardless 112# of whether they are re-compiled or not. 113# 114# See the file "Documentation/dev-tools/sparse.rst" for more details, 115# including where to get the "sparse" utility. 116 117ifeq ("$(origin C)", "command line") 118 KBUILD_CHECKSRC = $(C) 119endif 120ifndef KBUILD_CHECKSRC 121 KBUILD_CHECKSRC = 0 122endif 123 124export KBUILD_CHECKSRC 125 126# Enable "clippy" (a linter) as part of the Rust compilation. 127# 128# Use 'make CLIPPY=1' to enable it. 129ifeq ("$(origin CLIPPY)", "command line") 130 KBUILD_CLIPPY := $(CLIPPY) 131endif 132 133export KBUILD_CLIPPY 134 135# Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the 136# directory of external module to build. Setting M= takes precedence. 137ifeq ("$(origin M)", "command line") 138 KBUILD_EXTMOD := $(M) 139endif 140 141$(if $(word 2, $(KBUILD_EXTMOD)), \ 142 $(error building multiple external modules is not supported)) 143 144$(foreach x, % :, $(if $(findstring $x, $(KBUILD_EXTMOD)), \ 145 $(error module directory path cannot contain '$x'))) 146 147# Remove trailing slashes 148ifneq ($(filter %/, $(KBUILD_EXTMOD)),) 149KBUILD_EXTMOD := $(shell dirname $(KBUILD_EXTMOD).) 150endif 151 152export KBUILD_EXTMOD 153 154# Kbuild will save output files in the current working directory. 155# This does not need to match to the root of the kernel source tree. 156# 157# For example, you can do this: 158# 159# cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile 160# 161# If you want to save output files in a different location, there are 162# two syntaxes to specify it. 163# 164# 1) O= 165# Use "make O=dir/to/store/output/files/" 166# 167# 2) Set KBUILD_OUTPUT 168# Set the environment variable KBUILD_OUTPUT to point to the output directory. 169# export KBUILD_OUTPUT=dir/to/store/output/files/; make 170# 171# The O= assignment takes precedence over the KBUILD_OUTPUT environment 172# variable. 173 174# Do we want to change the working directory? 175ifeq ("$(origin O)", "command line") 176 KBUILD_OUTPUT := $(O) 177endif 178 179ifneq ($(KBUILD_OUTPUT),) 180# Make's built-in functions such as $(abspath ...), $(realpath ...) cannot 181# expand a shell special character '~'. We use a somewhat tedious way here. 182abs_objtree := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) && pwd) 183$(if $(abs_objtree),, \ 184 $(error failed to create output directory "$(KBUILD_OUTPUT)")) 185 186# $(realpath ...) resolves symlinks 187abs_objtree := $(realpath $(abs_objtree)) 188else 189abs_objtree := $(CURDIR) 190endif # ifneq ($(KBUILD_OUTPUT),) 191 192ifeq ($(abs_objtree),$(CURDIR)) 193# Suppress "Entering directory ..." unless we are changing the work directory. 194MAKEFLAGS += --no-print-directory 195else 196need-sub-make := 1 197endif 198 199this-makefile := $(lastword $(MAKEFILE_LIST)) 200abs_srctree := $(realpath $(dir $(this-makefile))) 201 202ifneq ($(words $(subst :, ,$(abs_srctree))), 1) 203$(error source directory cannot contain spaces or colons) 204endif 205 206ifneq ($(filter 3.%,$(MAKE_VERSION)),) 207# 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x 208# We need to invoke sub-make to avoid implicit rules in the top Makefile. 209need-sub-make := 1 210# Cancel implicit rules for this Makefile. 211$(this-makefile): ; 212endif 213 214export abs_srctree abs_objtree 215export sub_make_done := 1 216 217ifeq ($(need-sub-make),1) 218 219PHONY += $(MAKECMDGOALS) __sub-make 220 221$(filter-out $(this-makefile), $(MAKECMDGOALS)) __all: __sub-make 222 @: 223 224# Invoke a second make in the output directory, passing relevant variables 225__sub-make: 226 $(Q)$(MAKE) -C $(abs_objtree) -f $(abs_srctree)/Makefile $(MAKECMDGOALS) 227 228endif # need-sub-make 229endif # sub_make_done 230 231# We process the rest of the Makefile if this is the final invocation of make 232ifeq ($(need-sub-make),) 233 234# Do not print "Entering directory ...", 235# but we want to display it when entering to the output directory 236# so that IDEs/editors are able to understand relative filenames. 237MAKEFLAGS += --no-print-directory 238 239ifeq ($(abs_srctree),$(abs_objtree)) 240 # building in the source tree 241 srctree := . 242 building_out_of_srctree := 243else 244 ifeq ($(abs_srctree)/,$(dir $(abs_objtree))) 245 # building in a subdirectory of the source tree 246 srctree := .. 247 else 248 srctree := $(abs_srctree) 249 endif 250 building_out_of_srctree := 1 251endif 252 253ifneq ($(KBUILD_ABS_SRCTREE),) 254srctree := $(abs_srctree) 255endif 256 257objtree := . 258VPATH := $(srctree) 259 260export building_out_of_srctree srctree objtree VPATH 261 262# To make sure we do not include .config for any of the *config targets 263# catch them early, and hand them over to scripts/kconfig/Makefile 264# It is allowed to specify more targets when calling make, including 265# mixing *config targets and build targets. 266# For example 'make oldconfig all'. 267# Detect when mixed targets is specified, and make a second invocation 268# of make so .config is not included in this case either (for *config). 269 270version_h := include/generated/uapi/linux/version.h 271 272clean-targets := %clean mrproper cleandocs 273no-dot-config-targets := $(clean-targets) \ 274 cscope gtags TAGS tags help% %docs check% coccicheck \ 275 $(version_h) headers headers_% archheaders archscripts \ 276 %asm-generic kernelversion %src-pkg dt_binding_check \ 277 outputmakefile rustavailable rustfmt rustfmtcheck 278# Installation targets should not require compiler. Unfortunately, vdso_install 279# is an exception where build artifacts may be updated. This must be fixed. 280no-compiler-targets := $(no-dot-config-targets) install dtbs_install \ 281 headers_install modules_install kernelrelease image_name 282no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease \ 283 image_name 284single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.rsi %.s %.symtypes %/ 285 286config-build := 287mixed-build := 288need-config := 1 289need-compiler := 1 290may-sync-config := 1 291single-build := 292 293ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),) 294 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),) 295 need-config := 296 endif 297endif 298 299ifneq ($(filter $(no-compiler-targets), $(MAKECMDGOALS)),) 300 ifeq ($(filter-out $(no-compiler-targets), $(MAKECMDGOALS)),) 301 need-compiler := 302 endif 303endif 304 305ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),) 306 ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),) 307 may-sync-config := 308 endif 309endif 310 311ifneq ($(KBUILD_EXTMOD),) 312 may-sync-config := 313endif 314 315ifeq ($(KBUILD_EXTMOD),) 316 ifneq ($(filter %config,$(MAKECMDGOALS)),) 317 config-build := 1 318 ifneq ($(words $(MAKECMDGOALS)),1) 319 mixed-build := 1 320 endif 321 endif 322endif 323 324# We cannot build single targets and the others at the same time 325ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),) 326 single-build := 1 327 ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),) 328 mixed-build := 1 329 endif 330endif 331 332# For "make -j clean all", "make -j mrproper defconfig all", etc. 333ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),) 334 ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),) 335 mixed-build := 1 336 endif 337endif 338 339# install and modules_install need also be processed one by one 340ifneq ($(filter install,$(MAKECMDGOALS)),) 341 ifneq ($(filter modules_install,$(MAKECMDGOALS)),) 342 mixed-build := 1 343 endif 344endif 345 346ifdef mixed-build 347# =========================================================================== 348# We're called with mixed targets (*config and build targets). 349# Handle them one by one. 350 351PHONY += $(MAKECMDGOALS) __build_one_by_one 352 353$(MAKECMDGOALS): __build_one_by_one 354 @: 355 356__build_one_by_one: 357 $(Q)set -e; \ 358 for i in $(MAKECMDGOALS); do \ 359 $(MAKE) -f $(srctree)/Makefile $$i; \ 360 done 361 362else # !mixed-build 363 364include $(srctree)/scripts/Kbuild.include 365 366# Read KERNELRELEASE from include/config/kernel.release (if it exists) 367KERNELRELEASE = $(call read-file, include/config/kernel.release) 368KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION) 369export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION 370 371include $(srctree)/scripts/subarch.include 372 373# Cross compiling and selecting different set of gcc/bin-utils 374# --------------------------------------------------------------------------- 375# 376# When performing cross compilation for other architectures ARCH shall be set 377# to the target architecture. (See arch/* for the possibilities). 378# ARCH can be set during invocation of make: 379# make ARCH=ia64 380# Another way is to have ARCH set in the environment. 381# The default ARCH is the host where make is executed. 382 383# CROSS_COMPILE specify the prefix used for all executables used 384# during compilation. Only gcc and related bin-utils executables 385# are prefixed with $(CROSS_COMPILE). 386# CROSS_COMPILE can be set on the command line 387# make CROSS_COMPILE=ia64-linux- 388# Alternatively CROSS_COMPILE can be set in the environment. 389# Default value for CROSS_COMPILE is not to prefix executables 390# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile 391ARCH ?= $(SUBARCH) 392 393# Architecture as present in compile.h 394UTS_MACHINE := $(ARCH) 395SRCARCH := $(ARCH) 396 397# Additional ARCH settings for x86 398ifeq ($(ARCH),i386) 399 SRCARCH := x86 400endif 401ifeq ($(ARCH),x86_64) 402 SRCARCH := x86 403endif 404 405# Additional ARCH settings for sparc 406ifeq ($(ARCH),sparc32) 407 SRCARCH := sparc 408endif 409ifeq ($(ARCH),sparc64) 410 SRCARCH := sparc 411endif 412 413# Additional ARCH settings for parisc 414ifeq ($(ARCH),parisc64) 415 SRCARCH := parisc 416endif 417 418export cross_compiling := 419ifneq ($(SRCARCH),$(SUBARCH)) 420cross_compiling := 1 421endif 422 423KCONFIG_CONFIG ?= .config 424export KCONFIG_CONFIG 425 426# SHELL used by kbuild 427CONFIG_SHELL := sh 428 429HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null) 430HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null) 431HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null) 432 433ifneq ($(LLVM),) 434ifneq ($(filter %/,$(LLVM)),) 435LLVM_PREFIX := $(LLVM) 436else ifneq ($(filter -%,$(LLVM)),) 437LLVM_SUFFIX := $(LLVM) 438endif 439 440HOSTCC = $(LLVM_PREFIX)clang$(LLVM_SUFFIX) 441HOSTCXX = $(LLVM_PREFIX)clang++$(LLVM_SUFFIX) 442else 443HOSTCC = gcc 444HOSTCXX = g++ 445endif 446HOSTRUSTC = rustc 447HOSTPKG_CONFIG = pkg-config 448 449KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \ 450 -O2 -fomit-frame-pointer -std=gnu11 \ 451 -Wdeclaration-after-statement 452KBUILD_USERCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(USERCFLAGS) 453KBUILD_USERLDFLAGS := $(USERLDFLAGS) 454 455# These flags apply to all Rust code in the tree, including the kernel and 456# host programs. 457export rust_common_flags := --edition=2021 \ 458 -Zbinary_dep_depinfo=y \ 459 -Dunsafe_op_in_unsafe_fn -Drust_2018_idioms \ 460 -Dunreachable_pub -Dnon_ascii_idents \ 461 -Wmissing_docs \ 462 -Drustdoc::missing_crate_level_docs \ 463 -Dclippy::correctness -Dclippy::style \ 464 -Dclippy::suspicious -Dclippy::complexity \ 465 -Dclippy::perf \ 466 -Dclippy::let_unit_value -Dclippy::mut_mut \ 467 -Dclippy::needless_bitwise_bool \ 468 -Dclippy::needless_continue \ 469 -Wclippy::dbg_macro 470 471KBUILD_HOSTCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS) 472KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS) 473KBUILD_HOSTRUSTFLAGS := $(rust_common_flags) -O -Cstrip=debuginfo \ 474 -Zallow-features= $(HOSTRUSTFLAGS) 475KBUILD_HOSTLDFLAGS := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS) 476KBUILD_HOSTLDLIBS := $(HOST_LFS_LIBS) $(HOSTLDLIBS) 477 478# Make variables (CC, etc...) 479CPP = $(CC) -E 480ifneq ($(LLVM),) 481CC = $(LLVM_PREFIX)clang$(LLVM_SUFFIX) 482LD = $(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX) 483AR = $(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX) 484NM = $(LLVM_PREFIX)llvm-nm$(LLVM_SUFFIX) 485OBJCOPY = $(LLVM_PREFIX)llvm-objcopy$(LLVM_SUFFIX) 486OBJDUMP = $(LLVM_PREFIX)llvm-objdump$(LLVM_SUFFIX) 487READELF = $(LLVM_PREFIX)llvm-readelf$(LLVM_SUFFIX) 488STRIP = $(LLVM_PREFIX)llvm-strip$(LLVM_SUFFIX) 489else 490CC = $(CROSS_COMPILE)gcc 491LD = $(CROSS_COMPILE)ld 492AR = $(CROSS_COMPILE)ar 493NM = $(CROSS_COMPILE)nm 494OBJCOPY = $(CROSS_COMPILE)objcopy 495OBJDUMP = $(CROSS_COMPILE)objdump 496READELF = $(CROSS_COMPILE)readelf 497STRIP = $(CROSS_COMPILE)strip 498endif 499RUSTC = rustc 500RUSTDOC = rustdoc 501RUSTFMT = rustfmt 502CLIPPY_DRIVER = clippy-driver 503BINDGEN = bindgen 504CARGO = cargo 505PAHOLE = pahole 506RESOLVE_BTFIDS = $(objtree)/tools/bpf/resolve_btfids/resolve_btfids 507LEX = flex 508YACC = bison 509AWK = awk 510INSTALLKERNEL := installkernel 511DEPMOD = depmod 512PERL = perl 513PYTHON3 = python3 514CHECK = sparse 515BASH = bash 516KGZIP = gzip 517KBZIP2 = bzip2 518KLZOP = lzop 519LZMA = lzma 520LZ4 = lz4c 521XZ = xz 522ZSTD = zstd 523 524PAHOLE_FLAGS = $(shell PAHOLE=$(PAHOLE) $(srctree)/scripts/pahole-flags.sh) 525 526CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \ 527 -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF) 528NOSTDINC_FLAGS := 529CFLAGS_MODULE = 530RUSTFLAGS_MODULE = 531AFLAGS_MODULE = 532LDFLAGS_MODULE = 533CFLAGS_KERNEL = 534RUSTFLAGS_KERNEL = 535AFLAGS_KERNEL = 536LDFLAGS_vmlinux = 537 538# Use USERINCLUDE when you must reference the UAPI directories only. 539USERINCLUDE := \ 540 -I$(srctree)/arch/$(SRCARCH)/include/uapi \ 541 -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \ 542 -I$(srctree)/include/uapi \ 543 -I$(objtree)/include/generated/uapi \ 544 -include $(srctree)/include/linux/compiler-version.h \ 545 -include $(srctree)/include/linux/kconfig.h 546 547# Use LINUXINCLUDE when you must reference the include/ directory. 548# Needed to be compatible with the O= option 549LINUXINCLUDE := \ 550 -I$(srctree)/arch/$(SRCARCH)/include \ 551 -I$(objtree)/arch/$(SRCARCH)/include/generated \ 552 $(if $(building_out_of_srctree),-I$(srctree)/include) \ 553 -I$(objtree)/include \ 554 $(USERINCLUDE) 555 556KBUILD_AFLAGS := -D__ASSEMBLY__ -fno-PIE 557KBUILD_CFLAGS := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \ 558 -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \ 559 -Werror=implicit-function-declaration -Werror=implicit-int \ 560 -Werror=return-type -Wno-format-security -funsigned-char \ 561 -std=gnu11 562KBUILD_CPPFLAGS := -D__KERNEL__ 563KBUILD_RUSTFLAGS := $(rust_common_flags) \ 564 --target=$(objtree)/scripts/target.json \ 565 -Cpanic=abort -Cembed-bitcode=n -Clto=n \ 566 -Cforce-unwind-tables=n -Ccodegen-units=1 \ 567 -Csymbol-mangling-version=v0 \ 568 -Crelocation-model=static \ 569 -Zfunction-sections=n \ 570 -Dclippy::float_arithmetic 571 572KBUILD_AFLAGS_KERNEL := 573KBUILD_CFLAGS_KERNEL := 574KBUILD_RUSTFLAGS_KERNEL := 575KBUILD_AFLAGS_MODULE := -DMODULE 576KBUILD_CFLAGS_MODULE := -DMODULE 577KBUILD_RUSTFLAGS_MODULE := --cfg MODULE 578KBUILD_LDFLAGS_MODULE := 579KBUILD_LDFLAGS := 580CLANG_FLAGS := 581 582ifeq ($(KBUILD_CLIPPY),1) 583 RUSTC_OR_CLIPPY_QUIET := CLIPPY 584 RUSTC_OR_CLIPPY = $(CLIPPY_DRIVER) 585else 586 RUSTC_OR_CLIPPY_QUIET := RUSTC 587 RUSTC_OR_CLIPPY = $(RUSTC) 588endif 589 590ifdef RUST_LIB_SRC 591 export RUST_LIB_SRC 592endif 593 594# Allows the usage of unstable features in stable compilers. 595export RUSTC_BOOTSTRAP := 1 596 597export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG 598export RUSTC RUSTDOC RUSTFMT RUSTC_OR_CLIPPY_QUIET RUSTC_OR_CLIPPY BINDGEN CARGO 599export HOSTRUSTC KBUILD_HOSTRUSTFLAGS 600export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL 601export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX 602export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD 603export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE 604export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS 605 606export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS 607export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE 608export KBUILD_RUSTFLAGS RUSTFLAGS_KERNEL RUSTFLAGS_MODULE 609export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE 610export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_RUSTFLAGS_MODULE KBUILD_LDFLAGS_MODULE 611export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL KBUILD_RUSTFLAGS_KERNEL 612export PAHOLE_FLAGS 613 614# Files to ignore in find ... statements 615 616export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o \ 617 -name CVS -o -name .pc -o -name .hg -o -name .git \) \ 618 -prune -o 619export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \ 620 --exclude CVS --exclude .pc --exclude .hg --exclude .git 621 622# =========================================================================== 623# Rules shared between *config targets and build targets 624 625# Basic helpers built in scripts/basic/ 626PHONY += scripts_basic 627scripts_basic: 628 $(Q)$(MAKE) $(build)=scripts/basic 629 630PHONY += outputmakefile 631ifdef building_out_of_srctree 632# Before starting out-of-tree build, make sure the source tree is clean. 633# outputmakefile generates a Makefile in the output directory, if using a 634# separate output directory. This allows convenient use of make in the 635# output directory. 636# At the same time when output Makefile generated, generate .gitignore to 637# ignore whole output directory 638 639quiet_cmd_makefile = GEN Makefile 640 cmd_makefile = { \ 641 echo "\# Automatically generated by $(srctree)/Makefile: don't edit"; \ 642 echo "include $(srctree)/Makefile"; \ 643 } > Makefile 644 645outputmakefile: 646 @if [ -f $(srctree)/.config -o \ 647 -d $(srctree)/include/config -o \ 648 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \ 649 echo >&2 "***"; \ 650 echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \ 651 echo >&2 "*** in $(abs_srctree)";\ 652 echo >&2 "***"; \ 653 false; \ 654 fi 655 $(Q)ln -fsn $(srctree) source 656 $(call cmd,makefile) 657 $(Q)test -e .gitignore || \ 658 { echo "# this is build directory, ignore it"; echo "*"; } > .gitignore 659endif 660 661# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included. 662# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile. 663# CC_VERSION_TEXT is referenced from Kconfig (so it needs export), 664# and from include/config/auto.conf.cmd to detect the compiler upgrade. 665CC_VERSION_TEXT = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1)) 666 667ifneq ($(findstring clang,$(CC_VERSION_TEXT)),) 668include $(srctree)/scripts/Makefile.clang 669endif 670 671# Include this also for config targets because some architectures need 672# cc-cross-prefix to determine CROSS_COMPILE. 673ifdef need-compiler 674include $(srctree)/scripts/Makefile.compiler 675endif 676 677ifdef config-build 678# =========================================================================== 679# *config targets only - make sure prerequisites are updated, and descend 680# in scripts/kconfig to make the *config target 681 682# Read arch specific Makefile to set KBUILD_DEFCONFIG as needed. 683# KBUILD_DEFCONFIG may point out an alternative default configuration 684# used for 'make defconfig' 685include $(srctree)/arch/$(SRCARCH)/Makefile 686export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT 687 688config: outputmakefile scripts_basic FORCE 689 $(Q)$(MAKE) $(build)=scripts/kconfig $@ 690 691%config: outputmakefile scripts_basic FORCE 692 $(Q)$(MAKE) $(build)=scripts/kconfig $@ 693 694else #!config-build 695# =========================================================================== 696# Build targets only - this includes vmlinux, arch specific targets, clean 697# targets and others. In general all targets except *config targets. 698 699# If building an external module we do not care about the all: rule 700# but instead __all depend on modules 701PHONY += all 702ifeq ($(KBUILD_EXTMOD),) 703__all: all 704else 705__all: modules 706endif 707 708targets := 709 710# Decide whether to build built-in, modular, or both. 711# Normally, just do built-in. 712 713KBUILD_MODULES := 714KBUILD_BUILTIN := 1 715 716# If we have only "make modules", don't compile built-in objects. 717ifeq ($(MAKECMDGOALS),modules) 718 KBUILD_BUILTIN := 719endif 720 721# If we have "make <whatever> modules", compile modules 722# in addition to whatever we do anyway. 723# Just "make" or "make all" shall build modules as well 724 725ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),) 726 KBUILD_MODULES := 1 727endif 728 729ifeq ($(MAKECMDGOALS),) 730 KBUILD_MODULES := 1 731endif 732 733export KBUILD_MODULES KBUILD_BUILTIN 734 735ifdef need-config 736include include/config/auto.conf 737endif 738 739ifeq ($(KBUILD_EXTMOD),) 740# Objects we will link into vmlinux / subdirs we need to visit 741core-y := 742drivers-y := 743libs-y := lib/ 744endif # KBUILD_EXTMOD 745 746# The all: target is the default when no target is given on the 747# command line. 748# This allow a user to issue only 'make' to build a kernel including modules 749# Defaults to vmlinux, but the arch makefile usually adds further targets 750all: vmlinux 751 752CFLAGS_GCOV := -fprofile-arcs -ftest-coverage 753ifdef CONFIG_CC_IS_GCC 754CFLAGS_GCOV += -fno-tree-loop-im 755endif 756export CFLAGS_GCOV 757 758# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later. 759ifdef CONFIG_FUNCTION_TRACER 760 CC_FLAGS_FTRACE := -pg 761endif 762 763include $(srctree)/arch/$(SRCARCH)/Makefile 764 765ifdef need-config 766ifdef may-sync-config 767# Read in dependencies to all Kconfig* files, make sure to run syncconfig if 768# changes are detected. This should be included after arch/$(SRCARCH)/Makefile 769# because some architectures define CROSS_COMPILE there. 770include include/config/auto.conf.cmd 771 772$(KCONFIG_CONFIG): 773 @echo >&2 '***' 774 @echo >&2 '*** Configuration file "$@" not found!' 775 @echo >&2 '***' 776 @echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or' 777 @echo >&2 '*** "make menuconfig" or "make xconfig").' 778 @echo >&2 '***' 779 @/bin/false 780 781# The actual configuration files used during the build are stored in 782# include/generated/ and include/config/. Update them if .config is newer than 783# include/config/auto.conf (which mirrors .config). 784# 785# This exploits the 'multi-target pattern rule' trick. 786# The syncconfig should be executed only once to make all the targets. 787# (Note: use the grouped target '&:' when we bump to GNU Make 4.3) 788# 789# Do not use $(call cmd,...) here. That would suppress prompts from syncconfig, 790# so you cannot notice that Kconfig is waiting for the user input. 791%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h %/generated/rustc_cfg: $(KCONFIG_CONFIG) 792 $(Q)$(kecho) " SYNC $@" 793 $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig 794else # !may-sync-config 795# External modules and some install targets need include/generated/autoconf.h 796# and include/config/auto.conf but do not care if they are up-to-date. 797# Use auto.conf to trigger the test 798PHONY += include/config/auto.conf 799 800include/config/auto.conf: 801 @test -e include/generated/autoconf.h -a -e $@ || ( \ 802 echo >&2; \ 803 echo >&2 " ERROR: Kernel configuration is invalid."; \ 804 echo >&2 " include/generated/autoconf.h or $@ are missing.";\ 805 echo >&2 " Run 'make oldconfig && make prepare' on kernel src to fix it."; \ 806 echo >&2 ; \ 807 /bin/false) 808 809endif # may-sync-config 810endif # need-config 811 812KBUILD_CFLAGS += -fno-delete-null-pointer-checks 813KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,) 814KBUILD_CFLAGS += $(call cc-disable-warning, format-truncation) 815KBUILD_CFLAGS += $(call cc-disable-warning, format-overflow) 816KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member) 817 818ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE 819KBUILD_CFLAGS += -O2 820KBUILD_RUSTFLAGS += -Copt-level=2 821else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE 822KBUILD_CFLAGS += -Os 823KBUILD_RUSTFLAGS += -Copt-level=s 824endif 825 826# Always set `debug-assertions` and `overflow-checks` because their default 827# depends on `opt-level` and `debug-assertions`, respectively. 828KBUILD_RUSTFLAGS += -Cdebug-assertions=$(if $(CONFIG_RUST_DEBUG_ASSERTIONS),y,n) 829KBUILD_RUSTFLAGS += -Coverflow-checks=$(if $(CONFIG_RUST_OVERFLOW_CHECKS),y,n) 830 831# Tell gcc to never replace conditional load with a non-conditional one 832ifdef CONFIG_CC_IS_GCC 833# gcc-10 renamed --param=allow-store-data-races=0 to 834# -fno-allow-store-data-races. 835KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0) 836KBUILD_CFLAGS += $(call cc-option,-fno-allow-store-data-races) 837endif 838 839ifdef CONFIG_READABLE_ASM 840# Disable optimizations that make assembler listings hard to read. 841# reorder blocks reorders the control in the function 842# ipa clone creates specialized cloned functions 843# partial inlining inlines only parts of functions 844KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining 845endif 846 847ifneq ($(CONFIG_FRAME_WARN),0) 848KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN) 849endif 850 851stackp-flags-y := -fno-stack-protector 852stackp-flags-$(CONFIG_STACKPROTECTOR) := -fstack-protector 853stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG) := -fstack-protector-strong 854 855KBUILD_CFLAGS += $(stackp-flags-y) 856 857KBUILD_CPPFLAGS-$(CONFIG_WERROR) += -Werror 858KBUILD_CPPFLAGS += $(KBUILD_CPPFLAGS-y) 859KBUILD_CFLAGS-$(CONFIG_CC_NO_ARRAY_BOUNDS) += -Wno-array-bounds 860 861KBUILD_RUSTFLAGS-$(CONFIG_WERROR) += -Dwarnings 862KBUILD_RUSTFLAGS += $(KBUILD_RUSTFLAGS-y) 863 864ifdef CONFIG_CC_IS_CLANG 865# The kernel builds with '-std=gnu11' so use of GNU extensions is acceptable. 866KBUILD_CFLAGS += -Wno-gnu 867else 868 869# gcc inanely warns about local variables called 'main' 870KBUILD_CFLAGS += -Wno-main 871endif 872 873# These warnings generated too much noise in a regular build. 874# Use make W=1 to enable them (see scripts/Makefile.extrawarn) 875KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable) 876KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable) 877 878# These result in bogus false positives 879KBUILD_CFLAGS += $(call cc-disable-warning, dangling-pointer) 880 881ifdef CONFIG_FRAME_POINTER 882KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls 883KBUILD_RUSTFLAGS += -Cforce-frame-pointers=y 884else 885# Some targets (ARM with Thumb2, for example), can't be built with frame 886# pointers. For those, we don't have FUNCTION_TRACER automatically 887# select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is 888# incompatible with -fomit-frame-pointer with current GCC, so we don't use 889# -fomit-frame-pointer with FUNCTION_TRACER. 890# In the Rust target specification, "frame-pointer" is set explicitly 891# to "may-omit". 892ifndef CONFIG_FUNCTION_TRACER 893KBUILD_CFLAGS += -fomit-frame-pointer 894endif 895endif 896 897# Initialize all stack variables with a 0xAA pattern. 898ifdef CONFIG_INIT_STACK_ALL_PATTERN 899KBUILD_CFLAGS += -ftrivial-auto-var-init=pattern 900endif 901 902# Initialize all stack variables with a zero value. 903ifdef CONFIG_INIT_STACK_ALL_ZERO 904KBUILD_CFLAGS += -ftrivial-auto-var-init=zero 905ifdef CONFIG_CC_HAS_AUTO_VAR_INIT_ZERO_ENABLER 906# https://github.com/llvm/llvm-project/issues/44842 907CC_AUTO_VAR_INIT_ZERO_ENABLER := -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang 908export CC_AUTO_VAR_INIT_ZERO_ENABLER 909KBUILD_CFLAGS += $(CC_AUTO_VAR_INIT_ZERO_ENABLER) 910endif 911endif 912 913# While VLAs have been removed, GCC produces unreachable stack probes 914# for the randomize_kstack_offset feature. Disable it for all compilers. 915KBUILD_CFLAGS += $(call cc-option, -fno-stack-clash-protection) 916 917# Clear used registers at func exit (to reduce data lifetime and ROP gadgets). 918ifdef CONFIG_ZERO_CALL_USED_REGS 919KBUILD_CFLAGS += -fzero-call-used-regs=used-gpr 920endif 921 922ifdef CONFIG_FUNCTION_TRACER 923ifdef CONFIG_FTRACE_MCOUNT_USE_CC 924 CC_FLAGS_FTRACE += -mrecord-mcount 925 ifdef CONFIG_HAVE_NOP_MCOUNT 926 ifeq ($(call cc-option-yn, -mnop-mcount),y) 927 CC_FLAGS_FTRACE += -mnop-mcount 928 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT 929 endif 930 endif 931endif 932ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL 933 ifdef CONFIG_HAVE_OBJTOOL_NOP_MCOUNT 934 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT 935 endif 936endif 937ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT 938 ifdef CONFIG_HAVE_C_RECORDMCOUNT 939 BUILD_C_RECORDMCOUNT := y 940 export BUILD_C_RECORDMCOUNT 941 endif 942endif 943ifdef CONFIG_HAVE_FENTRY 944 # s390-linux-gnu-gcc did not support -mfentry until gcc-9. 945 ifeq ($(call cc-option-yn, -mfentry),y) 946 CC_FLAGS_FTRACE += -mfentry 947 CC_FLAGS_USING += -DCC_USING_FENTRY 948 endif 949endif 950export CC_FLAGS_FTRACE 951KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING) 952KBUILD_AFLAGS += $(CC_FLAGS_USING) 953endif 954 955# We trigger additional mismatches with less inlining 956ifdef CONFIG_DEBUG_SECTION_MISMATCH 957KBUILD_CFLAGS += -fno-inline-functions-called-once 958endif 959 960# `rustc`'s `-Zfunction-sections` applies to data too (as of 1.59.0). 961ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION 962KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections 963KBUILD_RUSTFLAGS_KERNEL += -Zfunction-sections=y 964LDFLAGS_vmlinux += --gc-sections 965endif 966 967ifdef CONFIG_SHADOW_CALL_STACK 968ifndef CONFIG_DYNAMIC_SCS 969CC_FLAGS_SCS := -fsanitize=shadow-call-stack 970KBUILD_CFLAGS += $(CC_FLAGS_SCS) 971endif 972export CC_FLAGS_SCS 973endif 974 975ifdef CONFIG_LTO_CLANG 976ifdef CONFIG_LTO_CLANG_THIN 977CC_FLAGS_LTO := -flto=thin -fsplit-lto-unit 978KBUILD_LDFLAGS += --thinlto-cache-dir=$(extmod_prefix).thinlto-cache 979else 980CC_FLAGS_LTO := -flto 981endif 982CC_FLAGS_LTO += -fvisibility=hidden 983 984# Limit inlining across translation units to reduce binary size 985KBUILD_LDFLAGS += -mllvm -import-instr-limit=5 986 987# Check for frame size exceeding threshold during prolog/epilog insertion 988# when using lld < 13.0.0. 989ifneq ($(CONFIG_FRAME_WARN),0) 990ifeq ($(call test-lt, $(CONFIG_LLD_VERSION), 130000),y) 991KBUILD_LDFLAGS += -plugin-opt=-warn-stack-size=$(CONFIG_FRAME_WARN) 992endif 993endif 994endif 995 996ifdef CONFIG_LTO 997KBUILD_CFLAGS += -fno-lto $(CC_FLAGS_LTO) 998KBUILD_AFLAGS += -fno-lto 999export CC_FLAGS_LTO 1000endif 1001 1002ifdef CONFIG_CFI_CLANG 1003CC_FLAGS_CFI := -fsanitize=kcfi 1004KBUILD_CFLAGS += $(CC_FLAGS_CFI) 1005export CC_FLAGS_CFI 1006endif 1007 1008ifneq ($(CONFIG_FUNCTION_ALIGNMENT),0) 1009KBUILD_CFLAGS += -falign-functions=$(CONFIG_FUNCTION_ALIGNMENT) 1010endif 1011 1012# arch Makefile may override CC so keep this after arch Makefile is included 1013NOSTDINC_FLAGS += -nostdinc 1014 1015# warn about C99 declaration after statement 1016KBUILD_CFLAGS += -Wdeclaration-after-statement 1017 1018# Variable Length Arrays (VLAs) should not be used anywhere in the kernel 1019KBUILD_CFLAGS += -Wvla 1020 1021# disable pointer signed / unsigned warnings in gcc 4.0 1022KBUILD_CFLAGS += -Wno-pointer-sign 1023 1024# In order to make sure new function cast mismatches are not introduced 1025# in the kernel (to avoid tripping CFI checking), the kernel should be 1026# globally built with -Wcast-function-type. 1027KBUILD_CFLAGS += $(call cc-option, -Wcast-function-type) 1028 1029# disable stringop warnings in gcc 8+ 1030KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation) 1031 1032# We'll want to enable this eventually, but it's not going away for 5.7 at least 1033KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow) 1034 1035# Another good warning that we'll want to enable eventually 1036KBUILD_CFLAGS += $(call cc-disable-warning, restrict) 1037 1038# Enabled with W=2, disabled by default as noisy 1039ifdef CONFIG_CC_IS_GCC 1040KBUILD_CFLAGS += -Wno-maybe-uninitialized 1041endif 1042 1043# The allocators already balk at large sizes, so silence the compiler 1044# warnings for bounds checks involving those possible values. While 1045# -Wno-alloc-size-larger-than would normally be used here, earlier versions 1046# of gcc (<9.1) weirdly don't handle the option correctly when _other_ 1047# warnings are produced (?!). Using -Walloc-size-larger-than=SIZE_MAX 1048# doesn't work (as it is documented to), silently resolving to "0" prior to 1049# version 9.1 (and producing an error more recently). Numeric values larger 1050# than PTRDIFF_MAX also don't work prior to version 9.1, which are silently 1051# ignored, continuing to default to PTRDIFF_MAX. So, left with no other 1052# choice, we must perform a versioned check to disable this warning. 1053# https://lore.kernel.org/lkml/20210824115859.187f272f@canb.auug.org.au 1054KBUILD_CFLAGS-$(call gcc-min-version, 90100) += -Wno-alloc-size-larger-than 1055KBUILD_CFLAGS += $(KBUILD_CFLAGS-y) $(CONFIG_CC_IMPLICIT_FALLTHROUGH) 1056 1057# disable invalid "can't wrap" optimizations for signed / pointers 1058KBUILD_CFLAGS += -fno-strict-overflow 1059 1060# Make sure -fstack-check isn't enabled (like gentoo apparently did) 1061KBUILD_CFLAGS += -fno-stack-check 1062 1063# conserve stack if available 1064ifdef CONFIG_CC_IS_GCC 1065KBUILD_CFLAGS += -fconserve-stack 1066endif 1067 1068# Prohibit date/time macros, which would make the build non-deterministic 1069KBUILD_CFLAGS += -Werror=date-time 1070 1071# enforce correct pointer usage 1072KBUILD_CFLAGS += $(call cc-option,-Werror=incompatible-pointer-types) 1073 1074# Require designated initializers for all marked structures 1075KBUILD_CFLAGS += $(call cc-option,-Werror=designated-init) 1076 1077# change __FILE__ to the relative path from the srctree 1078KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=) 1079 1080# include additional Makefiles when needed 1081include-y := scripts/Makefile.extrawarn 1082include-$(CONFIG_DEBUG_INFO) += scripts/Makefile.debug 1083include-$(CONFIG_KASAN) += scripts/Makefile.kasan 1084include-$(CONFIG_KCSAN) += scripts/Makefile.kcsan 1085include-$(CONFIG_KMSAN) += scripts/Makefile.kmsan 1086include-$(CONFIG_UBSAN) += scripts/Makefile.ubsan 1087include-$(CONFIG_KCOV) += scripts/Makefile.kcov 1088include-$(CONFIG_RANDSTRUCT) += scripts/Makefile.randstruct 1089include-$(CONFIG_GCC_PLUGINS) += scripts/Makefile.gcc-plugins 1090 1091include $(addprefix $(srctree)/, $(include-y)) 1092 1093# scripts/Makefile.gcc-plugins is intentionally included last. 1094# Do not add $(call cc-option,...) below this line. When you build the kernel 1095# from the clean source tree, the GCC plugins do not exist at this point. 1096 1097# Add user supplied CPPFLAGS, AFLAGS, CFLAGS and RUSTFLAGS as the last assignments 1098KBUILD_CPPFLAGS += $(KCPPFLAGS) 1099KBUILD_AFLAGS += $(KAFLAGS) 1100KBUILD_CFLAGS += $(KCFLAGS) 1101KBUILD_RUSTFLAGS += $(KRUSTFLAGS) 1102 1103KBUILD_LDFLAGS_MODULE += --build-id=sha1 1104LDFLAGS_vmlinux += --build-id=sha1 1105 1106KBUILD_LDFLAGS += -z noexecstack 1107ifeq ($(CONFIG_LD_IS_BFD),y) 1108KBUILD_LDFLAGS += $(call ld-option,--no-warn-rwx-segments) 1109endif 1110 1111ifeq ($(CONFIG_STRIP_ASM_SYMS),y) 1112LDFLAGS_vmlinux += -X 1113endif 1114 1115ifeq ($(CONFIG_RELR),y) 1116LDFLAGS_vmlinux += --pack-dyn-relocs=relr --use-android-relr-tags 1117endif 1118 1119# We never want expected sections to be placed heuristically by the 1120# linker. All sections should be explicitly named in the linker script. 1121ifdef CONFIG_LD_ORPHAN_WARN 1122LDFLAGS_vmlinux += --orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL) 1123endif 1124 1125# Align the bit size of userspace programs with the kernel 1126KBUILD_USERCFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS)) 1127KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS)) 1128 1129# make the checker run with the right architecture 1130CHECKFLAGS += --arch=$(ARCH) 1131 1132# insure the checker run with the right endianness 1133CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian) 1134 1135# the checker needs the correct machine size 1136CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32) 1137 1138# Default kernel image to build when no specific target is given. 1139# KBUILD_IMAGE may be overruled on the command line or 1140# set in the environment 1141# Also any assignments in arch/$(ARCH)/Makefile take precedence over 1142# this default value 1143export KBUILD_IMAGE ?= vmlinux 1144 1145# 1146# INSTALL_PATH specifies where to place the updated kernel and system map 1147# images. Default is /boot, but you can set it to other values 1148export INSTALL_PATH ?= /boot 1149 1150# 1151# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots. 1152# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as 1153# an argument if needed. Otherwise it defaults to the kernel install path 1154# 1155export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE) 1156 1157# 1158# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory 1159# relocations required by build roots. This is not defined in the 1160# makefile but the argument can be passed to make if needed. 1161# 1162 1163MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE) 1164export MODLIB 1165 1166PHONY += prepare0 1167 1168export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/) 1169export MODORDER := $(extmod_prefix)modules.order 1170export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps 1171 1172ifeq ($(KBUILD_EXTMOD),) 1173 1174build-dir := . 1175clean-dirs := $(sort . Documentation \ 1176 $(patsubst %/,%,$(filter %/, $(core-) \ 1177 $(drivers-) $(libs-)))) 1178 1179export ARCH_CORE := $(core-y) 1180export ARCH_LIB := $(filter %/, $(libs-y)) 1181export ARCH_DRIVERS := $(drivers-y) $(drivers-m) 1182# Externally visible symbols (used by link-vmlinux.sh) 1183 1184KBUILD_VMLINUX_OBJS := ./built-in.a 1185ifdef CONFIG_MODULES 1186KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y))) 1187KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y)) 1188else 1189KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y)) 1190endif 1191 1192export KBUILD_VMLINUX_LIBS 1193export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds 1194 1195# Recurse until adjust_autoksyms.sh is satisfied 1196PHONY += autoksyms_recursive 1197ifdef CONFIG_TRIM_UNUSED_KSYMS 1198# For the kernel to actually contain only the needed exported symbols, 1199# we have to build modules as well to determine what those symbols are. 1200# (this can be evaluated only once include/config/auto.conf has been included) 1201KBUILD_MODULES := 1 1202 1203autoksyms_recursive: $(build-dir) modules.order 1204 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \ 1205 "$(MAKE) -f $(srctree)/Makefile autoksyms_recursive" 1206endif 1207 1208autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h) 1209 1210quiet_cmd_autoksyms_h = GEN $@ 1211 cmd_autoksyms_h = mkdir -p $(dir $@); \ 1212 $(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@ 1213 1214$(autoksyms_h): 1215 $(call cmd,autoksyms_h) 1216 1217# '$(AR) mPi' needs 'T' to workaround the bug of llvm-ar <= 14 1218quiet_cmd_ar_vmlinux.a = AR $@ 1219 cmd_ar_vmlinux.a = \ 1220 rm -f $@; \ 1221 $(AR) cDPrST $@ $(KBUILD_VMLINUX_OBJS); \ 1222 $(AR) mPiT $$($(AR) t $@ | sed -n 1p) $@ $$($(AR) t $@ | grep -F -f $(srctree)/scripts/head-object-list.txt) 1223 1224targets += vmlinux.a 1225vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt autoksyms_recursive FORCE 1226 $(call if_changed,ar_vmlinux.a) 1227 1228PHONY += vmlinux_o 1229vmlinux_o: vmlinux.a $(KBUILD_VMLINUX_LIBS) 1230 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o 1231 1232vmlinux.o modules.builtin.modinfo modules.builtin: vmlinux_o 1233 @: 1234 1235PHONY += vmlinux 1236# LDFLAGS_vmlinux in the top Makefile defines linker flags for the top vmlinux, 1237# not for decompressors. LDFLAGS_vmlinux in arch/*/boot/compressed/Makefile is 1238# unrelated; the decompressors just happen to have the same base name, 1239# arch/*/boot/compressed/vmlinux. 1240# Export LDFLAGS_vmlinux only to scripts/Makefile.vmlinux. 1241# 1242# _LDFLAGS_vmlinux is a workaround for the 'private export' bug: 1243# https://savannah.gnu.org/bugs/?61463 1244# For Make > 4.4, the following simple code will work: 1245# vmlinux: private export LDFLAGS_vmlinux := $(LDFLAGS_vmlinux) 1246vmlinux: private _LDFLAGS_vmlinux := $(LDFLAGS_vmlinux) 1247vmlinux: export LDFLAGS_vmlinux = $(_LDFLAGS_vmlinux) 1248vmlinux: vmlinux.o $(KBUILD_LDS) modpost 1249 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux 1250 1251# The actual objects are generated when descending, 1252# make sure no implicit rule kicks in 1253$(sort $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)): . ; 1254 1255ifeq ($(origin KERNELRELEASE),file) 1256filechk_kernel.release = $(srctree)/scripts/setlocalversion $(srctree) 1257else 1258filechk_kernel.release = echo $(KERNELRELEASE) 1259endif 1260 1261# Store (new) KERNELRELEASE string in include/config/kernel.release 1262include/config/kernel.release: FORCE 1263 $(call filechk,kernel.release) 1264 1265# Additional helpers built in scripts/ 1266# Carefully list dependencies so we do not try to build scripts twice 1267# in parallel 1268PHONY += scripts 1269scripts: scripts_basic scripts_dtc 1270 $(Q)$(MAKE) $(build)=$(@) 1271 1272# Things we need to do before we recursively start building the kernel 1273# or the modules are listed in "prepare". 1274# A multi level approach is used. prepareN is processed before prepareN-1. 1275# archprepare is used in arch Makefiles and when processed asm symlink, 1276# version.h and scripts_basic is processed / created. 1277 1278PHONY += prepare archprepare 1279 1280archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \ 1281 asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h \ 1282 include/generated/compile.h include/generated/autoconf.h remove-stale-files 1283 1284prepare0: archprepare 1285 $(Q)$(MAKE) $(build)=scripts/mod 1286 $(Q)$(MAKE) $(build)=. prepare 1287 1288# All the preparing.. 1289prepare: prepare0 1290ifdef CONFIG_RUST 1291 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh -v 1292 $(Q)$(MAKE) $(build)=rust 1293endif 1294 1295PHONY += remove-stale-files 1296remove-stale-files: 1297 $(Q)$(srctree)/scripts/remove-stale-files 1298 1299# Support for using generic headers in asm-generic 1300asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj 1301 1302PHONY += asm-generic uapi-asm-generic 1303asm-generic: uapi-asm-generic 1304 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \ 1305 generic=include/asm-generic 1306uapi-asm-generic: 1307 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \ 1308 generic=include/uapi/asm-generic 1309 1310# Generate some files 1311# --------------------------------------------------------------------------- 1312 1313# KERNELRELEASE can change from a few different places, meaning version.h 1314# needs to be updated, so this check is forced on all builds 1315 1316uts_len := 64 1317define filechk_utsrelease.h 1318 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \ 1319 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \ 1320 exit 1; \ 1321 fi; \ 1322 echo \#define UTS_RELEASE \"$(KERNELRELEASE)\" 1323endef 1324 1325define filechk_version.h 1326 if [ $(SUBLEVEL) -gt 255 ]; then \ 1327 echo \#define LINUX_VERSION_CODE $(shell \ 1328 expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \ 1329 else \ 1330 echo \#define LINUX_VERSION_CODE $(shell \ 1331 expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \ 1332 fi; \ 1333 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + \ 1334 ((c) > 255 ? 255 : (c)))'; \ 1335 echo \#define LINUX_VERSION_MAJOR $(VERSION); \ 1336 echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL); \ 1337 echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL) 1338endef 1339 1340$(version_h): PATCHLEVEL := $(or $(PATCHLEVEL), 0) 1341$(version_h): SUBLEVEL := $(or $(SUBLEVEL), 0) 1342$(version_h): FORCE 1343 $(call filechk,version.h) 1344 1345include/generated/utsrelease.h: include/config/kernel.release FORCE 1346 $(call filechk,utsrelease.h) 1347 1348filechk_compile.h = $(srctree)/scripts/mkcompile_h \ 1349 "$(UTS_MACHINE)" "$(CONFIG_CC_VERSION_TEXT)" "$(LD)" 1350 1351include/generated/compile.h: FORCE 1352 $(call filechk,compile.h) 1353 1354PHONY += headerdep 1355headerdep: 1356 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \ 1357 $(srctree)/scripts/headerdep.pl -I$(srctree)/include 1358 1359# --------------------------------------------------------------------------- 1360# Kernel headers 1361 1362#Default location for installed headers 1363export INSTALL_HDR_PATH = $(objtree)/usr 1364 1365quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include 1366 cmd_headers_install = \ 1367 mkdir -p $(INSTALL_HDR_PATH); \ 1368 rsync -mrl --include='*/' --include='*\.h' --exclude='*' \ 1369 usr/include $(INSTALL_HDR_PATH) 1370 1371PHONY += headers_install 1372headers_install: headers 1373 $(call cmd,headers_install) 1374 1375PHONY += archheaders archscripts 1376 1377hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj 1378 1379PHONY += headers 1380headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts 1381 $(if $(filter um, $(SRCARCH)), $(error Headers not exportable for UML)) 1382 $(Q)$(MAKE) $(hdr-inst)=include/uapi 1383 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi 1384 1385ifdef CONFIG_HEADERS_INSTALL 1386prepare: headers 1387endif 1388 1389PHONY += scripts_unifdef 1390scripts_unifdef: scripts_basic 1391 $(Q)$(MAKE) $(build)=scripts scripts/unifdef 1392 1393# --------------------------------------------------------------------------- 1394# Install 1395 1396# Many distributions have the custom install script, /sbin/installkernel. 1397# If DKMS is installed, 'make install' will eventually recurse back 1398# to this Makefile to build and install external modules. 1399# Cancel sub_make_done so that options such as M=, V=, etc. are parsed. 1400 1401quiet_cmd_install = INSTALL $(INSTALL_PATH) 1402 cmd_install = unset sub_make_done; $(srctree)/scripts/install.sh 1403 1404# --------------------------------------------------------------------------- 1405# Tools 1406 1407ifdef CONFIG_OBJTOOL 1408prepare: tools/objtool 1409endif 1410 1411ifdef CONFIG_BPF 1412ifdef CONFIG_DEBUG_INFO_BTF 1413prepare: tools/bpf/resolve_btfids 1414endif 1415endif 1416 1417PHONY += resolve_btfids_clean 1418 1419resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids 1420 1421# tools/bpf/resolve_btfids directory might not exist 1422# in output directory, skip its clean in that case 1423resolve_btfids_clean: 1424ifneq ($(wildcard $(resolve_btfids_O)),) 1425 $(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean 1426endif 1427 1428# Clear a bunch of variables before executing the submake 1429ifeq ($(quiet),silent_) 1430tools_silent=s 1431endif 1432 1433tools/: FORCE 1434 $(Q)mkdir -p $(objtree)/tools 1435 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ 1436 1437tools/%: FORCE 1438 $(Q)mkdir -p $(objtree)/tools 1439 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $* 1440 1441# --------------------------------------------------------------------------- 1442# Kernel selftest 1443 1444PHONY += kselftest 1445kselftest: headers 1446 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests 1447 1448kselftest-%: headers FORCE 1449 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $* 1450 1451PHONY += kselftest-merge 1452kselftest-merge: 1453 $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!)) 1454 $(Q)find $(srctree)/tools/testing/selftests -name config | \ 1455 xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config 1456 $(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig 1457 1458# --------------------------------------------------------------------------- 1459# Devicetree files 1460 1461ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),) 1462dtstree := arch/$(SRCARCH)/boot/dts 1463endif 1464 1465ifneq ($(dtstree),) 1466 1467%.dtb: dtbs_prepare 1468 $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@ 1469 1470%.dtbo: dtbs_prepare 1471 $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@ 1472 1473PHONY += dtbs dtbs_prepare dtbs_install dtbs_check 1474dtbs: dtbs_prepare 1475 $(Q)$(MAKE) $(build)=$(dtstree) 1476 1477# include/config/kernel.release is actually needed when installing DTBs because 1478# INSTALL_DTBS_PATH contains $(KERNELRELEASE). However, we do not want to make 1479# dtbs_install depend on it as dtbs_install may run as root. 1480dtbs_prepare: include/config/kernel.release scripts_dtc 1481 1482ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),) 1483export CHECK_DTBS=y 1484endif 1485 1486ifneq ($(CHECK_DTBS),) 1487dtbs_prepare: dt_binding_check 1488endif 1489 1490dtbs_check: dtbs 1491 1492dtbs_install: 1493 $(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH) 1494 1495ifdef CONFIG_OF_EARLY_FLATTREE 1496all: dtbs 1497endif 1498 1499endif 1500 1501PHONY += scripts_dtc 1502scripts_dtc: scripts_basic 1503 $(Q)$(MAKE) $(build)=scripts/dtc 1504 1505ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),) 1506export CHECK_DT_BINDING=y 1507endif 1508 1509PHONY += dt_binding_check 1510dt_binding_check: scripts_dtc 1511 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings 1512 1513PHONY += dt_compatible_check 1514dt_compatible_check: dt_binding_check 1515 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@ 1516 1517# --------------------------------------------------------------------------- 1518# Modules 1519 1520ifdef CONFIG_MODULES 1521 1522# By default, build modules as well 1523 1524all: modules 1525 1526# When we're building modules with modversions, we need to consider 1527# the built-in objects during the descend as well, in order to 1528# make sure the checksums are up to date before we record them. 1529ifdef CONFIG_MODVERSIONS 1530 KBUILD_BUILTIN := 1 1531endif 1532 1533# Build modules 1534# 1535 1536# *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFO_BTF_MODULES 1537# is an exception. 1538ifdef CONFIG_DEBUG_INFO_BTF_MODULES 1539KBUILD_BUILTIN := 1 1540modules: vmlinux 1541endif 1542 1543modules: modules_prepare 1544 1545# Target to prepare building external modules 1546modules_prepare: prepare 1547 $(Q)$(MAKE) $(build)=scripts scripts/module.lds 1548 1549export modules_sign_only := 1550 1551ifeq ($(CONFIG_MODULE_SIG),y) 1552PHONY += modules_sign 1553modules_sign: modules_install 1554 @: 1555 1556# modules_sign is a subset of modules_install. 1557# 'make modules_install modules_sign' is equivalent to 'make modules_install'. 1558ifeq ($(filter modules_install,$(MAKECMDGOALS)),) 1559modules_sign_only := y 1560endif 1561endif 1562 1563modinst_pre := 1564ifneq ($(filter modules_install,$(MAKECMDGOALS)),) 1565modinst_pre := __modinst_pre 1566endif 1567 1568modules_install: $(modinst_pre) 1569PHONY += __modinst_pre 1570__modinst_pre: 1571 @rm -rf $(MODLIB)/kernel 1572 @rm -f $(MODLIB)/source 1573 @mkdir -p $(MODLIB)/kernel 1574 @ln -s $(abspath $(srctree)) $(MODLIB)/source 1575 @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \ 1576 rm -f $(MODLIB)/build ; \ 1577 ln -s $(CURDIR) $(MODLIB)/build ; \ 1578 fi 1579 @sed 's:^\(.*\)\.o$$:kernel/\1.ko:' modules.order > $(MODLIB)/modules.order 1580 @cp -f modules.builtin $(MODLIB)/ 1581 @cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/ 1582 1583endif # CONFIG_MODULES 1584 1585### 1586# Cleaning is done on three levels. 1587# make clean Delete most generated files 1588# Leave enough to build external modules 1589# make mrproper Delete the current configuration, and all generated files 1590# make distclean Remove editor backup files, patch leftover files and the like 1591 1592# Directories & files removed with 'make clean' 1593CLEAN_FILES += include/ksym vmlinux.symvers modules-only.symvers \ 1594 modules.builtin modules.builtin.modinfo modules.nsdeps \ 1595 compile_commands.json .thinlto-cache rust/test rust/doc \ 1596 rust-project.json .vmlinux.objs .vmlinux.export.c 1597 1598# Directories & files removed with 'make mrproper' 1599MRPROPER_FILES += include/config include/generated \ 1600 arch/$(SRCARCH)/include/generated .objdiff \ 1601 debian snap tar-install \ 1602 .config .config.old .version \ 1603 Module.symvers \ 1604 certs/signing_key.pem \ 1605 certs/x509.genkey \ 1606 vmlinux-gdb.py \ 1607 *.spec rpmbuild \ 1608 rust/libmacros.so 1609 1610# clean - Delete most, but leave enough to build external modules 1611# 1612clean: rm-files := $(CLEAN_FILES) 1613 1614PHONY += archclean vmlinuxclean 1615 1616vmlinuxclean: 1617 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean 1618 $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean) 1619 1620clean: archclean vmlinuxclean resolve_btfids_clean 1621 1622# mrproper - Delete all generated files, including .config 1623# 1624mrproper: rm-files := $(wildcard $(MRPROPER_FILES)) 1625mrproper-dirs := $(addprefix _mrproper_,scripts) 1626 1627PHONY += $(mrproper-dirs) mrproper 1628$(mrproper-dirs): 1629 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@) 1630 1631mrproper: clean $(mrproper-dirs) 1632 $(call cmd,rmfiles) 1633 @find . $(RCS_FIND_IGNORE) \ 1634 \( -name '*.rmeta' \) \ 1635 -type f -print | xargs rm -f 1636 1637# distclean 1638# 1639PHONY += distclean 1640 1641distclean: mrproper 1642 @find . $(RCS_FIND_IGNORE) \ 1643 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \ 1644 -o -name '*.bak' -o -name '#*#' -o -name '*%' \ 1645 -o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \ 1646 -o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \ 1647 -type f -print | xargs rm -f 1648 1649 1650# Packaging of the kernel to various formats 1651# --------------------------------------------------------------------------- 1652 1653%src-pkg: FORCE 1654 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@ 1655%pkg: include/config/kernel.release FORCE 1656 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@ 1657 1658# Brief documentation of the typical targets used 1659# --------------------------------------------------------------------------- 1660 1661boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig) 1662boards := $(sort $(notdir $(boards))) 1663board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig)) 1664board-dirs := $(sort $(notdir $(board-dirs:/=))) 1665 1666PHONY += help 1667help: 1668 @echo 'Cleaning targets:' 1669 @echo ' clean - Remove most generated files but keep the config and' 1670 @echo ' enough build support to build external modules' 1671 @echo ' mrproper - Remove all generated files + config + various backup files' 1672 @echo ' distclean - mrproper + remove editor backup and patch files' 1673 @echo '' 1674 @echo 'Configuration targets:' 1675 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help 1676 @echo '' 1677 @echo 'Other generic targets:' 1678 @echo ' all - Build all targets marked with [*]' 1679 @echo '* vmlinux - Build the bare kernel' 1680 @echo '* modules - Build all modules' 1681 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)' 1682 @echo ' dir/ - Build all files in dir and below' 1683 @echo ' dir/file.[ois] - Build specified target only' 1684 @echo ' dir/file.ll - Build the LLVM assembly file' 1685 @echo ' (requires compiler support for LLVM assembly generation)' 1686 @echo ' dir/file.lst - Build specified mixed source/assembly target only' 1687 @echo ' (requires a recent binutils and recent build (System.map))' 1688 @echo ' dir/file.ko - Build module including final link' 1689 @echo ' modules_prepare - Set up for building external modules' 1690 @echo ' tags/TAGS - Generate tags file for editors' 1691 @echo ' cscope - Generate cscope index' 1692 @echo ' gtags - Generate GNU GLOBAL index' 1693 @echo ' kernelrelease - Output the release version string (use with make -s)' 1694 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)' 1695 @echo ' image_name - Output the image name (use with make -s)' 1696 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \ 1697 echo ' (default: $(INSTALL_HDR_PATH))'; \ 1698 echo '' 1699 @echo 'Static analysers:' 1700 @echo ' checkstack - Generate a list of stack hogs' 1701 @echo ' versioncheck - Sanity check on version.h usage' 1702 @echo ' includecheck - Check for duplicate included header files' 1703 @echo ' export_report - List the usages of all exported symbols' 1704 @echo ' headerdep - Detect inclusion cycles in headers' 1705 @echo ' coccicheck - Check with Coccinelle' 1706 @echo ' clang-analyzer - Check with clang static analyzer' 1707 @echo ' clang-tidy - Check with clang-tidy' 1708 @echo '' 1709 @echo 'Tools:' 1710 @echo ' nsdeps - Generate missing symbol namespace dependencies' 1711 @echo '' 1712 @echo 'Kernel selftest:' 1713 @echo ' kselftest - Build and run kernel selftest' 1714 @echo ' Build, install, and boot kernel before' 1715 @echo ' running kselftest on it' 1716 @echo ' Run as root for full coverage' 1717 @echo ' kselftest-all - Build kernel selftest' 1718 @echo ' kselftest-install - Build and install kernel selftest' 1719 @echo ' kselftest-clean - Remove all generated kselftest files' 1720 @echo ' kselftest-merge - Merge all the config dependencies of' 1721 @echo ' kselftest to existing .config.' 1722 @echo '' 1723 @echo 'Rust targets:' 1724 @echo ' rustavailable - Checks whether the Rust toolchain is' 1725 @echo ' available and, if not, explains why.' 1726 @echo ' rustfmt - Reformat all the Rust code in the kernel' 1727 @echo ' rustfmtcheck - Checks if all the Rust code in the kernel' 1728 @echo ' is formatted, printing a diff otherwise.' 1729 @echo ' rustdoc - Generate Rust documentation' 1730 @echo ' (requires kernel .config)' 1731 @echo ' rusttest - Runs the Rust tests' 1732 @echo ' (requires kernel .config; downloads external repos)' 1733 @echo ' rust-analyzer - Generate rust-project.json rust-analyzer support file' 1734 @echo ' (requires kernel .config)' 1735 @echo ' dir/file.[os] - Build specified target only' 1736 @echo ' dir/file.rsi - Build macro expanded source, similar to C preprocessing.' 1737 @echo ' Run with RUSTFMT=n to skip reformatting if needed.' 1738 @echo ' The output is not intended to be compilable.' 1739 @echo ' dir/file.ll - Build the LLVM assembly file' 1740 @echo '' 1741 @$(if $(dtstree), \ 1742 echo 'Devicetree:'; \ 1743 echo '* dtbs - Build device tree blobs for enabled boards'; \ 1744 echo ' dtbs_install - Install dtbs to $(INSTALL_DTBS_PATH)'; \ 1745 echo ' dt_binding_check - Validate device tree binding documents'; \ 1746 echo ' dtbs_check - Validate device tree source files';\ 1747 echo '') 1748 1749 @echo 'Userspace tools targets:' 1750 @echo ' use "make tools/help"' 1751 @echo ' or "cd tools; make help"' 1752 @echo '' 1753 @echo 'Kernel packaging:' 1754 @$(MAKE) -f $(srctree)/scripts/Makefile.package help 1755 @echo '' 1756 @echo 'Documentation targets:' 1757 @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp 1758 @echo '' 1759 @echo 'Architecture specific targets ($(SRCARCH)):' 1760 @$(or $(archhelp),\ 1761 echo ' No architecture specific help defined for $(SRCARCH)') 1762 @echo '' 1763 @$(if $(boards), \ 1764 $(foreach b, $(boards), \ 1765 printf " %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \ 1766 echo '') 1767 @$(if $(board-dirs), \ 1768 $(foreach b, $(board-dirs), \ 1769 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \ 1770 printf " %-16s - Show all of the above\\n" help-boards; \ 1771 echo '') 1772 1773 @echo ' make V=n [targets] 1: verbose build' 1774 @echo ' 2: give reason for rebuild of target' 1775 @echo ' V=1 and V=2 can be combined with V=12' 1776 @echo ' make O=dir [targets] Locate all output files in "dir", including .config' 1777 @echo ' make C=1 [targets] Check re-compiled c source with $$CHECK' 1778 @echo ' (sparse by default)' 1779 @echo ' make C=2 [targets] Force check of all c source with $$CHECK' 1780 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections' 1781 @echo ' make W=n [targets] Enable extra build checks, n=1,2,3 where' 1782 @echo ' 1: warnings which may be relevant and do not occur too often' 1783 @echo ' 2: warnings which occur quite often but may still be relevant' 1784 @echo ' 3: more obscure warnings, can most likely be ignored' 1785 @echo ' e: warnings are being treated as errors' 1786 @echo ' Multiple levels can be combined with W=12 or W=123' 1787 @$(if $(dtstree), \ 1788 echo ' make CHECK_DTBS=1 [targets] Check all generated dtb files against schema'; \ 1789 echo ' This can be applied both to "dtbs" and to individual "foo.dtb" targets' ; \ 1790 ) 1791 @echo '' 1792 @echo 'Execute "make" or "make all" to build all targets marked with [*] ' 1793 @echo 'For further info see the ./README file' 1794 1795 1796help-board-dirs := $(addprefix help-,$(board-dirs)) 1797 1798help-boards: $(help-board-dirs) 1799 1800boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig))) 1801 1802$(help-board-dirs): help-%: 1803 @echo 'Architecture specific targets ($(SRCARCH) $*):' 1804 @$(if $(boards-per-dir), \ 1805 $(foreach b, $(boards-per-dir), \ 1806 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \ 1807 echo '') 1808 1809 1810# Documentation targets 1811# --------------------------------------------------------------------------- 1812DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \ 1813 linkcheckdocs dochelp refcheckdocs texinfodocs infodocs 1814PHONY += $(DOC_TARGETS) 1815$(DOC_TARGETS): 1816 $(Q)$(MAKE) $(build)=Documentation $@ 1817 1818 1819# Rust targets 1820# --------------------------------------------------------------------------- 1821 1822# "Is Rust available?" target 1823PHONY += rustavailable 1824rustavailable: 1825 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh -v && echo "Rust is available!" 1826 1827# Documentation target 1828# 1829# Using the singular to avoid running afoul of `no-dot-config-targets`. 1830PHONY += rustdoc 1831rustdoc: prepare 1832 $(Q)$(MAKE) $(build)=rust $@ 1833 1834# Testing target 1835PHONY += rusttest 1836rusttest: prepare 1837 $(Q)$(MAKE) $(build)=rust $@ 1838 1839# Formatting targets 1840PHONY += rustfmt rustfmtcheck 1841 1842# We skip `rust/alloc` since we want to minimize the diff w.r.t. upstream. 1843# 1844# We match using absolute paths since `find` does not resolve them 1845# when matching, which is a problem when e.g. `srctree` is `..`. 1846# We `grep` afterwards in order to remove the directory entry itself. 1847rustfmt: 1848 $(Q)find $(abs_srctree) -type f -name '*.rs' \ 1849 -o -path $(abs_srctree)/rust/alloc -prune \ 1850 -o -path $(abs_objtree)/rust/test -prune \ 1851 | grep -Fv $(abs_srctree)/rust/alloc \ 1852 | grep -Fv $(abs_objtree)/rust/test \ 1853 | grep -Fv generated \ 1854 | xargs $(RUSTFMT) $(rustfmt_flags) 1855 1856rustfmtcheck: rustfmt_flags = --check 1857rustfmtcheck: rustfmt 1858 1859# IDE support targets 1860PHONY += rust-analyzer 1861rust-analyzer: 1862 $(Q)$(MAKE) $(build)=rust $@ 1863 1864# Misc 1865# --------------------------------------------------------------------------- 1866 1867PHONY += misc-check 1868misc-check: 1869 $(Q)$(srctree)/scripts/misc-check 1870 1871all: misc-check 1872 1873PHONY += scripts_gdb 1874scripts_gdb: prepare0 1875 $(Q)$(MAKE) $(build)=scripts/gdb 1876 $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py) 1877 1878ifdef CONFIG_GDB_SCRIPTS 1879all: scripts_gdb 1880endif 1881 1882else # KBUILD_EXTMOD 1883 1884filechk_kernel.release = echo $(KERNELRELEASE) 1885 1886### 1887# External module support. 1888# When building external modules the kernel used as basis is considered 1889# read-only, and no consistency checks are made and the make 1890# system is not used on the basis kernel. If updates are required 1891# in the basis kernel ordinary make commands (without M=...) must be used. 1892 1893# We are always building only modules. 1894KBUILD_BUILTIN := 1895KBUILD_MODULES := 1 1896 1897build-dir := $(KBUILD_EXTMOD) 1898 1899compile_commands.json: $(extmod_prefix)compile_commands.json 1900PHONY += compile_commands.json 1901 1902clean-dirs := $(KBUILD_EXTMOD) 1903clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \ 1904 $(KBUILD_EXTMOD)/compile_commands.json $(KBUILD_EXTMOD)/.thinlto-cache 1905 1906PHONY += prepare 1907# now expand this into a simple variable to reduce the cost of shell evaluations 1908prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT) 1909prepare: 1910 @if [ "$(CC_VERSION_TEXT)" != "$(CONFIG_CC_VERSION_TEXT)" ]; then \ 1911 echo >&2 "warning: the compiler differs from the one used to build the kernel"; \ 1912 echo >&2 " The kernel was built by: $(CONFIG_CC_VERSION_TEXT)"; \ 1913 echo >&2 " You are using: $(CC_VERSION_TEXT)"; \ 1914 fi 1915 1916PHONY += help 1917help: 1918 @echo ' Building external modules.' 1919 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target' 1920 @echo '' 1921 @echo ' modules - default target, build the module(s)' 1922 @echo ' modules_install - install the module' 1923 @echo ' clean - remove generated files in module directory only' 1924 @echo '' 1925 1926endif # KBUILD_EXTMOD 1927 1928# --------------------------------------------------------------------------- 1929# Modules 1930 1931PHONY += modules modules_install modules_prepare 1932 1933ifdef CONFIG_MODULES 1934 1935$(MODORDER): $(build-dir) 1936 @: 1937 1938# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules. 1939# This is solely useful to speed up test compiles. 1940modules: modpost 1941ifneq ($(KBUILD_MODPOST_NOFINAL),1) 1942 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal 1943endif 1944 1945PHONY += modules_check 1946modules_check: $(MODORDER) 1947 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $< 1948 1949quiet_cmd_depmod = DEPMOD $(MODLIB) 1950 cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \ 1951 $(KERNELRELEASE) 1952 1953modules_install: 1954 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst 1955 $(call cmd,depmod) 1956 1957else # CONFIG_MODULES 1958 1959# Modules not configured 1960# --------------------------------------------------------------------------- 1961 1962modules modules_install: 1963 @echo >&2 '***' 1964 @echo >&2 '*** The present kernel configuration has modules disabled.' 1965 @echo >&2 '*** To use the module feature, please run "make menuconfig" etc.' 1966 @echo >&2 '*** to enable CONFIG_MODULES.' 1967 @echo >&2 '***' 1968 @exit 1 1969 1970KBUILD_MODULES := 1971 1972endif # CONFIG_MODULES 1973 1974PHONY += modpost 1975modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \ 1976 $(if $(KBUILD_MODULES), modules_check) 1977 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost 1978 1979# Single targets 1980# --------------------------------------------------------------------------- 1981# To build individual files in subdirectories, you can do like this: 1982# 1983# make foo/bar/baz.s 1984# 1985# The supported suffixes for single-target are listed in 'single-targets' 1986# 1987# To build only under specific subdirectories, you can do like this: 1988# 1989# make foo/bar/baz/ 1990 1991ifdef single-build 1992 1993# .ko is special because modpost is needed 1994single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS))) 1995single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \ 1996 $(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko))) 1997 1998$(single-ko): single_modules 1999 @: 2000$(single-no-ko): $(build-dir) 2001 @: 2002 2003# Remove MODORDER when done because it is not the real one. 2004PHONY += single_modules 2005single_modules: $(single-no-ko) modules_prepare 2006 $(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$(m:%.ko=%.o);) } > $(MODORDER) 2007 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost 2008ifneq ($(KBUILD_MODPOST_NOFINAL),1) 2009 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal 2010endif 2011 $(Q)rm -f $(MODORDER) 2012 2013single-goals := $(addprefix $(build-dir)/, $(single-no-ko)) 2014 2015KBUILD_MODULES := 1 2016 2017endif 2018 2019# Preset locale variables to speed up the build process. Limit locale 2020# tweaks to this spot to avoid wrong language settings when running 2021# make menuconfig etc. 2022# Error messages still appears in the original language 2023PHONY += $(build-dir) 2024$(build-dir): prepare 2025 $(Q)$(MAKE) $(build)=$@ need-builtin=1 need-modorder=1 $(single-goals) 2026 2027clean-dirs := $(addprefix _clean_, $(clean-dirs)) 2028PHONY += $(clean-dirs) clean 2029$(clean-dirs): 2030 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@) 2031 2032clean: $(clean-dirs) 2033 $(call cmd,rmfiles) 2034 @find $(or $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \ 2035 \( -name '*.[aios]' -o -name '*.rsi' -o -name '*.ko' -o -name '.*.cmd' \ 2036 -o -name '*.ko.*' \ 2037 -o -name '*.dtb' -o -name '*.dtbo' \ 2038 -o -name '*.dtb.S' -o -name '*.dtbo.S' \ 2039 -o -name '*.dt.yaml' \ 2040 -o -name '*.dwo' -o -name '*.lst' \ 2041 -o -name '*.su' -o -name '*.mod' -o -name '*.usyms' \ 2042 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \ 2043 -o -name '*.lex.c' -o -name '*.tab.[ch]' \ 2044 -o -name '*.asn1.[ch]' \ 2045 -o -name '*.symtypes' -o -name 'modules.order' \ 2046 -o -name '*.c.[012]*.*' \ 2047 -o -name '*.ll' \ 2048 -o -name '*.gcno' \ 2049 -o -name '*.*.symversions' \) -type f -print \ 2050 -o -name '.tmp_*' -print \ 2051 | xargs rm -rf 2052 2053# Generate tags for editors 2054# --------------------------------------------------------------------------- 2055quiet_cmd_tags = GEN $@ 2056 cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@ 2057 2058tags TAGS cscope gtags: FORCE 2059 $(call cmd,tags) 2060 2061# Script to generate missing namespace dependencies 2062# --------------------------------------------------------------------------- 2063 2064PHONY += nsdeps 2065nsdeps: export KBUILD_NSDEPS=1 2066nsdeps: modules 2067 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps 2068 2069# Clang Tooling 2070# --------------------------------------------------------------------------- 2071 2072quiet_cmd_gen_compile_commands = GEN $@ 2073 cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs)) 2074 2075$(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \ 2076 $(if $(KBUILD_EXTMOD),, vmlinux.a $(KBUILD_VMLINUX_LIBS)) \ 2077 $(if $(CONFIG_MODULES), $(MODORDER)) FORCE 2078 $(call if_changed,gen_compile_commands) 2079 2080targets += $(extmod_prefix)compile_commands.json 2081 2082PHONY += clang-tidy clang-analyzer 2083 2084ifdef CONFIG_CC_IS_CLANG 2085quiet_cmd_clang_tools = CHECK $< 2086 cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $< 2087 2088clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json 2089 $(call cmd,clang_tools) 2090else 2091clang-tidy clang-analyzer: 2092 @echo "$@ requires CC=clang" >&2 2093 @false 2094endif 2095 2096# Scripts to check various things for consistency 2097# --------------------------------------------------------------------------- 2098 2099PHONY += includecheck versioncheck coccicheck export_report 2100 2101includecheck: 2102 find $(srctree)/* $(RCS_FIND_IGNORE) \ 2103 -name '*.[hcS]' -type f -print | sort \ 2104 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl 2105 2106versioncheck: 2107 find $(srctree)/* $(RCS_FIND_IGNORE) \ 2108 -name '*.[hcS]' -type f -print | sort \ 2109 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl 2110 2111coccicheck: 2112 $(Q)$(BASH) $(srctree)/scripts/$@ 2113 2114export_report: 2115 $(PERL) $(srctree)/scripts/export_report.pl 2116 2117PHONY += checkstack kernelrelease kernelversion image_name 2118 2119# UML needs a little special treatment here. It wants to use the host 2120# toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone 2121# else wants $(ARCH), including people doing cross-builds, which means 2122# that $(SUBARCH) doesn't work here. 2123ifeq ($(ARCH), um) 2124CHECKSTACK_ARCH := $(SUBARCH) 2125else 2126CHECKSTACK_ARCH := $(ARCH) 2127endif 2128checkstack: 2129 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \ 2130 $(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH) 2131 2132kernelrelease: 2133 @$(filechk_kernel.release) 2134 2135kernelversion: 2136 @echo $(KERNELVERSION) 2137 2138image_name: 2139 @echo $(KBUILD_IMAGE) 2140 2141quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files))) 2142 cmd_rmfiles = rm -rf $(rm-files) 2143 2144# read saved command lines for existing targets 2145existing-targets := $(wildcard $(sort $(targets))) 2146 2147-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd) 2148 2149endif # config-build 2150endif # mixed-build 2151endif # need-sub-make 2152 2153PHONY += FORCE 2154FORCE: 2155 2156# Declare the contents of the PHONY variable as phony. We keep that 2157# information in a variable so we can use it in if_changed and friends. 2158.PHONY: $(PHONY) 2159