1 # SPDX-License-Identifier: GPL-2.0
6 NAME = Hurr durr I'ma ninja sloth
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.
14 ifeq ($(filter undefine,$(.FEATURES)),)
15 $(error GNU Make >= 3.82 is required. Your Make version is $(MAKE_VERSION))
18 $(if $(filter __%, $(MAKECMDGOALS)), \
19 $(error targets prefixed with '__' are only for internal use))
21 # That's our default target when none is given on the command line
25 # We are using a recursive build, so we need to do a little thinking
26 # to get the ordering right.
28 # Most importantly: sub-Makefiles should only ever modify files in
29 # their own directory. If in some directory we have a dependency on
30 # a file in another dir (which doesn't happen often, but it's often
31 # unavoidable when linking the built-in.a targets which finally
32 # turn into vmlinux), we will call a sub make in that other dir, and
33 # after that we are sure that everything which is in that other dir
36 # The only cases where we need to modify files which have global
37 # effects are thus separated out and done before the recursive
38 # descending is started. They are now explicitly listed as the
41 ifneq ($(sub_make_done),1)
43 # Do not use make's built-in rules and variables
44 # (this increases performance and avoids hard-to-debug behaviour)
47 # Avoid funny character set dependencies
51 export LC_COLLATE LC_NUMERIC
53 # Avoid interference with shell env settings
57 # ---------------------------------------------------------------------------
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.
64 # quiet_cmd_depmod = DEPMOD $(MODLIB)
65 # cmd_depmod = $(srctree)/scripts/depmod.sh $(DEPMOD) $(KERNELRELEASE)
67 # A simple variant is to prefix commands with $(Q) - that's useful
68 # for commands that shall be hidden in non-verbose mode.
70 # $(Q)$(MAKE) $(build)=scripts/basic
72 # If KBUILD_VERBOSE contains 1, the whole command is echoed.
73 # If KBUILD_VERBOSE contains 2, the reason for rebuilding is printed.
75 # To put more focus on warnings, be less verbose as default
76 # Use 'make V=1' to see the full commands
78 ifeq ("$(origin V)", "command line")
85 ifneq ($(findstring 1, $(KBUILD_VERBOSE)),)
90 # If the user is running make -s (silent mode), suppress echoing of
92 # make-4.0 (and later) keep single letter options in the 1st word of MAKEFLAGS.
94 ifeq ($(filter 3.%,$(MAKE_VERSION)),)
95 short-opts := $(firstword -$(MAKEFLAGS))
97 short-opts := $(filter-out --%,$(MAKEFLAGS))
100 ifneq ($(findstring s,$(short-opts)),)
102 override KBUILD_VERBOSE :=
105 export quiet Q KBUILD_VERBOSE
107 # Call a source code checker (by default, "sparse") as part of the
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.
114 # See the file "Documentation/dev-tools/sparse.rst" for more details,
115 # including where to get the "sparse" utility.
117 ifeq ("$(origin C)", "command line")
118 KBUILD_CHECKSRC = $(C)
120 ifndef KBUILD_CHECKSRC
124 export KBUILD_CHECKSRC
126 # Enable "clippy" (a linter) as part of the Rust compilation.
128 # Use 'make CLIPPY=1' to enable it.
129 ifeq ("$(origin CLIPPY)", "command line")
130 KBUILD_CLIPPY := $(CLIPPY)
135 # Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
136 # directory of external module to build. Setting M= takes precedence.
137 ifeq ("$(origin M)", "command line")
138 KBUILD_EXTMOD := $(M)
141 $(if $(word 2, $(KBUILD_EXTMOD)), \
142 $(error building multiple external modules is not supported))
144 $(foreach x, % :, $(if $(findstring $x, $(KBUILD_EXTMOD)), \
145 $(error module directory path cannot contain '$x')))
147 # Remove trailing slashes
148 ifneq ($(filter %/, $(KBUILD_EXTMOD)),)
149 KBUILD_EXTMOD := $(shell dirname $(KBUILD_EXTMOD).)
154 # Kbuild will save output files in the current working directory.
155 # This does not need to match to the root of the kernel source tree.
157 # For example, you can do this:
159 # cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
161 # If you want to save output files in a different location, there are
162 # two syntaxes to specify it.
165 # Use "make O=dir/to/store/output/files/"
167 # 2) Set KBUILD_OUTPUT
168 # Set the environment variable KBUILD_OUTPUT to point to the output directory.
169 # export KBUILD_OUTPUT=dir/to/store/output/files/; make
171 # The O= assignment takes precedence over the KBUILD_OUTPUT environment
174 # Do we want to change the working directory?
175 ifeq ("$(origin O)", "command line")
176 KBUILD_OUTPUT := $(O)
179 ifneq ($(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.
182 abs_objtree := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) && pwd)
183 $(if $(abs_objtree),, \
184 $(error failed to create output directory "$(KBUILD_OUTPUT)"))
186 # $(realpath ...) resolves symlinks
187 abs_objtree := $(realpath $(abs_objtree))
189 abs_objtree := $(CURDIR)
190 endif # ifneq ($(KBUILD_OUTPUT),)
192 ifeq ($(abs_objtree),$(CURDIR))
193 # Suppress "Entering directory ..." unless we are changing the work directory.
194 MAKEFLAGS += --no-print-directory
199 this-makefile := $(lastword $(MAKEFILE_LIST))
200 abs_srctree := $(realpath $(dir $(this-makefile)))
202 ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
203 $(error source directory cannot contain spaces or colons)
206 ifneq ($(filter 3.%,$(MAKE_VERSION)),)
207 # 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
208 # We need to invoke sub-make to avoid implicit rules in the top Makefile.
210 # Cancel implicit rules for this Makefile.
214 export abs_srctree abs_objtree
215 export sub_make_done := 1
217 ifeq ($(need-sub-make),1)
219 PHONY += $(MAKECMDGOALS) __sub-make
221 $(filter-out $(this-makefile), $(MAKECMDGOALS)) __all: __sub-make
224 # Invoke a second make in the output directory, passing relevant variables
226 $(Q)$(MAKE) -C $(abs_objtree) -f $(abs_srctree)/Makefile $(MAKECMDGOALS)
228 endif # need-sub-make
229 endif # sub_make_done
231 # We process the rest of the Makefile if this is the final invocation of make
232 ifeq ($(need-sub-make),)
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.
237 MAKEFLAGS += --no-print-directory
239 ifeq ($(abs_srctree),$(abs_objtree))
240 # building in the source tree
242 building_out_of_srctree :=
244 ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
245 # building in a subdirectory of the source tree
248 srctree := $(abs_srctree)
250 building_out_of_srctree := 1
253 ifneq ($(KBUILD_ABS_SRCTREE),)
254 srctree := $(abs_srctree)
260 export building_out_of_srctree srctree objtree VPATH
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).
270 version_h := include/generated/uapi/linux/version.h
272 clean-targets := %clean mrproper cleandocs
273 no-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.
280 no-compiler-targets := $(no-dot-config-targets) install dtbs_install \
281 headers_install modules_install kernelrelease image_name
282 no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease \
284 single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.rsi %.s %.symtypes %/
293 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
294 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
299 ifneq ($(filter $(no-compiler-targets), $(MAKECMDGOALS)),)
300 ifeq ($(filter-out $(no-compiler-targets), $(MAKECMDGOALS)),)
305 ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
306 ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
311 ifneq ($(KBUILD_EXTMOD),)
315 ifeq ($(KBUILD_EXTMOD),)
316 ifneq ($(filter %config,$(MAKECMDGOALS)),)
318 ifneq ($(words $(MAKECMDGOALS)),1)
324 # We cannot build single targets and the others at the same time
325 ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
327 ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
332 # For "make -j clean all", "make -j mrproper defconfig all", etc.
333 ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
334 ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
339 # install and modules_install need also be processed one by one
340 ifneq ($(filter install,$(MAKECMDGOALS)),)
341 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
347 # ===========================================================================
348 # We're called with mixed targets (*config and build targets).
349 # Handle them one by one.
351 PHONY += $(MAKECMDGOALS) __build_one_by_one
353 $(MAKECMDGOALS): __build_one_by_one
358 for i in $(MAKECMDGOALS); do \
359 $(MAKE) -f $(srctree)/Makefile $$i; \
364 include $(srctree)/scripts/Kbuild.include
366 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
367 KERNELRELEASE = $(call read-file, include/config/kernel.release)
368 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
369 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
371 include $(srctree)/scripts/subarch.include
373 # Cross compiling and selecting different set of gcc/bin-utils
374 # ---------------------------------------------------------------------------
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:
380 # Another way is to have ARCH set in the environment.
381 # The default ARCH is the host where make is executed.
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
393 # Architecture as present in compile.h
394 UTS_MACHINE := $(ARCH)
397 # Additional ARCH settings for x86
401 ifeq ($(ARCH),x86_64)
405 # Additional ARCH settings for sparc
406 ifeq ($(ARCH),sparc32)
409 ifeq ($(ARCH),sparc64)
413 # Additional ARCH settings for parisc
414 ifeq ($(ARCH),parisc64)
418 export cross_compiling :=
419 ifneq ($(SRCARCH),$(SUBARCH))
423 KCONFIG_CONFIG ?= .config
424 export KCONFIG_CONFIG
426 # SHELL used by kbuild
429 HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
430 HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
431 HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
434 ifneq ($(filter %/,$(LLVM)),)
435 LLVM_PREFIX := $(LLVM)
436 else ifneq ($(filter -%,$(LLVM)),)
437 LLVM_SUFFIX := $(LLVM)
440 HOSTCC = $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
441 HOSTCXX = $(LLVM_PREFIX)clang++$(LLVM_SUFFIX)
447 HOSTPKG_CONFIG = pkg-config
449 KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
450 -O2 -fomit-frame-pointer -std=gnu11 \
451 -Wdeclaration-after-statement
452 KBUILD_USERCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(USERCFLAGS)
453 KBUILD_USERLDFLAGS := $(USERLDFLAGS)
455 # These flags apply to all Rust code in the tree, including the kernel and
457 export 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 \
462 -Drustdoc::missing_crate_level_docs \
463 -Dclippy::correctness -Dclippy::style \
464 -Dclippy::suspicious -Dclippy::complexity \
466 -Dclippy::let_unit_value -Dclippy::mut_mut \
467 -Dclippy::needless_bitwise_bool \
468 -Dclippy::needless_continue \
471 KBUILD_HOSTCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
472 KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
473 KBUILD_HOSTRUSTFLAGS := $(rust_common_flags) -O -Cstrip=debuginfo \
474 -Zallow-features= $(HOSTRUSTFLAGS)
475 KBUILD_HOSTLDFLAGS := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
476 KBUILD_HOSTLDLIBS := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
478 # Make variables (CC, etc...)
481 CC = $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
482 LD = $(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX)
483 AR = $(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX)
484 NM = $(LLVM_PREFIX)llvm-nm$(LLVM_SUFFIX)
485 OBJCOPY = $(LLVM_PREFIX)llvm-objcopy$(LLVM_SUFFIX)
486 OBJDUMP = $(LLVM_PREFIX)llvm-objdump$(LLVM_SUFFIX)
487 READELF = $(LLVM_PREFIX)llvm-readelf$(LLVM_SUFFIX)
488 STRIP = $(LLVM_PREFIX)llvm-strip$(LLVM_SUFFIX)
490 CC = $(CROSS_COMPILE)gcc
491 LD = $(CROSS_COMPILE)ld
492 AR = $(CROSS_COMPILE)ar
493 NM = $(CROSS_COMPILE)nm
494 OBJCOPY = $(CROSS_COMPILE)objcopy
495 OBJDUMP = $(CROSS_COMPILE)objdump
496 READELF = $(CROSS_COMPILE)readelf
497 STRIP = $(CROSS_COMPILE)strip
502 CLIPPY_DRIVER = clippy-driver
506 RESOLVE_BTFIDS = $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
510 INSTALLKERNEL := installkernel
524 PAHOLE_FLAGS = $(shell PAHOLE=$(PAHOLE) $(srctree)/scripts/pahole-flags.sh)
526 CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
527 -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
538 # Use USERINCLUDE when you must reference the UAPI directories only.
540 -I$(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 $(srctree)/include/linux/kconfig.h
547 # Use LINUXINCLUDE when you must reference the include/ directory.
548 # Needed to be compatible with the O= option
550 -I$(srctree)/arch/$(SRCARCH)/include \
551 -I$(objtree)/arch/$(SRCARCH)/include/generated \
552 $(if $(building_out_of_srctree),-I$(srctree)/include) \
553 -I$(objtree)/include \
556 KBUILD_AFLAGS := -D__ASSEMBLY__ -fno-PIE
557 KBUILD_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 \
562 KBUILD_CPPFLAGS := -D__KERNEL__
563 KBUILD_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
572 KBUILD_AFLAGS_KERNEL :=
573 KBUILD_CFLAGS_KERNEL :=
574 KBUILD_RUSTFLAGS_KERNEL :=
575 KBUILD_AFLAGS_MODULE := -DMODULE
576 KBUILD_CFLAGS_MODULE := -DMODULE
577 KBUILD_RUSTFLAGS_MODULE := --cfg MODULE
578 KBUILD_LDFLAGS_MODULE :=
582 ifeq ($(KBUILD_CLIPPY),1)
583 RUSTC_OR_CLIPPY_QUIET := CLIPPY
584 RUSTC_OR_CLIPPY = $(CLIPPY_DRIVER)
586 RUSTC_OR_CLIPPY_QUIET := RUSTC
587 RUSTC_OR_CLIPPY = $(RUSTC)
594 # Allows the usage of unstable features in stable compilers.
595 export RUSTC_BOOTSTRAP := 1
597 export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG
598 export RUSTC RUSTDOC RUSTFMT RUSTC_OR_CLIPPY_QUIET RUSTC_OR_CLIPPY BINDGEN CARGO
599 export HOSTRUSTC KBUILD_HOSTRUSTFLAGS
600 export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
601 export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
602 export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
603 export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
604 export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS
606 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
607 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
608 export KBUILD_RUSTFLAGS RUSTFLAGS_KERNEL RUSTFLAGS_MODULE
609 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
610 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_RUSTFLAGS_MODULE KBUILD_LDFLAGS_MODULE
611 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL KBUILD_RUSTFLAGS_KERNEL
614 # Files to ignore in find ... statements
616 export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o \
617 -name CVS -o -name .pc -o -name .hg -o -name .git \) \
619 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
620 --exclude CVS --exclude .pc --exclude .hg --exclude .git
622 # ===========================================================================
623 # Rules shared between *config targets and build targets
625 # Basic helpers built in scripts/basic/
626 PHONY += scripts_basic
628 $(Q)$(MAKE) $(build)=scripts/basic
630 PHONY += outputmakefile
631 ifdef 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
636 # At the same time when output Makefile generated, generate .gitignore to
637 # ignore whole output directory
639 quiet_cmd_makefile = GEN Makefile
641 echo "\# Automatically generated by $(srctree)/Makefile: don't edit"; \
642 echo "include $(srctree)/Makefile"; \
646 @if [ -f $(srctree)/.config -o \
647 -d $(srctree)/include/config -o \
648 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
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)";\
655 $(Q)ln -fsn $(srctree) source
657 $(Q)test -e .gitignore || \
658 { echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
661 # The expansion should be delayed until arch/$(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.
665 CC_VERSION_TEXT = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1))
667 ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
668 include $(srctree)/scripts/Makefile.clang
671 # Include this also for config targets because some architectures need
672 # cc-cross-prefix to determine CROSS_COMPILE.
674 include $(srctree)/scripts/Makefile.compiler
678 # ===========================================================================
679 # *config targets only - make sure prerequisites are updated, and descend
680 # in scripts/kconfig to make the *config target
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'
685 include $(srctree)/arch/$(SRCARCH)/Makefile
686 export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
688 config: outputmakefile scripts_basic FORCE
689 $(Q)$(MAKE) $(build)=scripts/kconfig $@
691 %config: outputmakefile scripts_basic FORCE
692 $(Q)$(MAKE) $(build)=scripts/kconfig $@
695 # ===========================================================================
696 # Build targets only - this includes vmlinux, arch specific targets, clean
697 # targets and others. In general all targets except *config targets.
699 # If building an external module we do not care about the all: rule
700 # but instead __all depend on modules
702 ifeq ($(KBUILD_EXTMOD),)
710 # Decide whether to build built-in, modular, or both.
711 # Normally, just do built-in.
716 # If we have only "make modules", don't compile built-in objects.
717 ifeq ($(MAKECMDGOALS),modules)
721 # If we have "make <whatever> modules", compile modules
722 # in addition to whatever we do anyway.
723 # Just "make" or "make all" shall build modules as well
725 ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
729 ifeq ($(MAKECMDGOALS),)
733 export KBUILD_MODULES KBUILD_BUILTIN
736 include include/config/auto.conf
739 ifeq ($(KBUILD_EXTMOD),)
740 # Objects we will link into vmlinux / subdirs we need to visit
744 endif # KBUILD_EXTMOD
746 # The all: target is the default when no target is given on the
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
752 CFLAGS_GCOV := -fprofile-arcs -ftest-coverage
753 ifdef CONFIG_CC_IS_GCC
754 CFLAGS_GCOV += -fno-tree-loop-im
758 # The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
759 ifdef CONFIG_FUNCTION_TRACER
760 CC_FLAGS_FTRACE := -pg
763 include $(srctree)/arch/$(SRCARCH)/Makefile
766 ifdef 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/$(SRCARCH)/Makefile
769 # because some architectures define CROSS_COMPILE there.
770 include include/config/auto.conf.cmd
774 @echo >&2 '*** Configuration file "$@" not found!'
776 @echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
777 @echo >&2 '*** "make menuconfig" or "make xconfig").'
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).
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)
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
794 else # !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
798 PHONY += include/config/auto.conf
800 include/config/auto.conf:
801 @test -e include/generated/autoconf.h -a -e $@ || ( \
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."; \
809 endif # may-sync-config
812 KBUILD_CFLAGS += -fno-delete-null-pointer-checks
813 KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,)
814 KBUILD_CFLAGS += $(call cc-disable-warning, format-truncation)
815 KBUILD_CFLAGS += $(call cc-disable-warning, format-overflow)
816 KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
818 ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
820 KBUILD_RUSTFLAGS += -Copt-level=2
821 else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
823 KBUILD_RUSTFLAGS += -Copt-level=s
826 # Always set `debug-assertions` and `overflow-checks` because their default
827 # depends on `opt-level` and `debug-assertions`, respectively.
828 KBUILD_RUSTFLAGS += -Cdebug-assertions=$(if $(CONFIG_RUST_DEBUG_ASSERTIONS),y,n)
829 KBUILD_RUSTFLAGS += -Coverflow-checks=$(if $(CONFIG_RUST_OVERFLOW_CHECKS),y,n)
831 # Tell gcc to never replace conditional load with a non-conditional one
832 ifdef CONFIG_CC_IS_GCC
833 # gcc-10 renamed --param=allow-store-data-races=0 to
834 # -fno-allow-store-data-races.
835 KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
836 KBUILD_CFLAGS += $(call cc-option,-fno-allow-store-data-races)
839 ifdef CONFIG_READABLE_ASM
840 # Disable optimizations that make assembler listings hard to read.
841 # reorder blocks reorders the control in the function
842 # ipa clone creates specialized cloned functions
843 # partial inlining inlines only parts of functions
844 KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
847 ifneq ($(CONFIG_FRAME_WARN),0)
848 KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
851 stackp-flags-y := -fno-stack-protector
852 stackp-flags-$(CONFIG_STACKPROTECTOR) := -fstack-protector
853 stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG) := -fstack-protector-strong
855 KBUILD_CFLAGS += $(stackp-flags-y)
857 KBUILD_CPPFLAGS-$(CONFIG_WERROR) += -Werror
858 KBUILD_CPPFLAGS += $(KBUILD_CPPFLAGS-y)
859 KBUILD_CFLAGS-$(CONFIG_CC_NO_ARRAY_BOUNDS) += -Wno-array-bounds
861 KBUILD_RUSTFLAGS-$(CONFIG_WERROR) += -Dwarnings
862 KBUILD_RUSTFLAGS += $(KBUILD_RUSTFLAGS-y)
864 ifdef CONFIG_CC_IS_CLANG
865 # The kernel builds with '-std=gnu11' so use of GNU extensions is acceptable.
866 KBUILD_CFLAGS += -Wno-gnu
869 # gcc inanely warns about local variables called 'main'
870 KBUILD_CFLAGS += -Wno-main
873 # These warnings generated too much noise in a regular build.
874 # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
875 KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
876 KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
878 # These result in bogus false positives
879 KBUILD_CFLAGS += $(call cc-disable-warning, dangling-pointer)
881 ifdef CONFIG_FRAME_POINTER
882 KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
883 KBUILD_RUSTFLAGS += -Cforce-frame-pointers=y
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
892 ifndef CONFIG_FUNCTION_TRACER
893 KBUILD_CFLAGS += -fomit-frame-pointer
897 # Initialize all stack variables with a 0xAA pattern.
898 ifdef CONFIG_INIT_STACK_ALL_PATTERN
899 KBUILD_CFLAGS += -ftrivial-auto-var-init=pattern
902 # Initialize all stack variables with a zero value.
903 ifdef CONFIG_INIT_STACK_ALL_ZERO
904 KBUILD_CFLAGS += -ftrivial-auto-var-init=zero
905 ifdef CONFIG_CC_HAS_AUTO_VAR_INIT_ZERO_ENABLER
906 # https://github.com/llvm/llvm-project/issues/44842
907 CC_AUTO_VAR_INIT_ZERO_ENABLER := -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
908 export CC_AUTO_VAR_INIT_ZERO_ENABLER
909 KBUILD_CFLAGS += $(CC_AUTO_VAR_INIT_ZERO_ENABLER)
913 # While VLAs have been removed, GCC produces unreachable stack probes
914 # for the randomize_kstack_offset feature. Disable it for all compilers.
915 KBUILD_CFLAGS += $(call cc-option, -fno-stack-clash-protection)
917 # Clear used registers at func exit (to reduce data lifetime and ROP gadgets).
918 ifdef CONFIG_ZERO_CALL_USED_REGS
919 KBUILD_CFLAGS += -fzero-call-used-regs=used-gpr
922 ifdef CONFIG_FUNCTION_TRACER
923 ifdef CONFIG_FTRACE_MCOUNT_USE_CC
924 CC_FLAGS_FTRACE += -mrecord-mcount
925 ifdef CONFIG_HAVE_NOP_MCOUNT
926 ifeq ($(call cc-option-yn, -mnop-mcount),y)
927 CC_FLAGS_FTRACE += -mnop-mcount
928 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
932 ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
933 ifdef CONFIG_HAVE_OBJTOOL_NOP_MCOUNT
934 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
937 ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
938 ifdef CONFIG_HAVE_C_RECORDMCOUNT
939 BUILD_C_RECORDMCOUNT := y
940 export BUILD_C_RECORDMCOUNT
943 ifdef 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
950 export CC_FLAGS_FTRACE
951 KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
952 KBUILD_AFLAGS += $(CC_FLAGS_USING)
955 # We trigger additional mismatches with less inlining
956 ifdef CONFIG_DEBUG_SECTION_MISMATCH
957 KBUILD_CFLAGS += -fno-inline-functions-called-once
960 # `rustc`'s `-Zfunction-sections` applies to data too (as of 1.59.0).
961 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
962 KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
963 KBUILD_RUSTFLAGS_KERNEL += -Zfunction-sections=y
964 LDFLAGS_vmlinux += --gc-sections
967 ifdef CONFIG_SHADOW_CALL_STACK
968 ifndef CONFIG_DYNAMIC_SCS
969 CC_FLAGS_SCS := -fsanitize=shadow-call-stack
970 KBUILD_CFLAGS += $(CC_FLAGS_SCS)
975 ifdef CONFIG_LTO_CLANG
976 ifdef CONFIG_LTO_CLANG_THIN
977 CC_FLAGS_LTO := -flto=thin -fsplit-lto-unit
978 KBUILD_LDFLAGS += --thinlto-cache-dir=$(extmod_prefix).thinlto-cache
980 CC_FLAGS_LTO := -flto
982 CC_FLAGS_LTO += -fvisibility=hidden
984 # Limit inlining across translation units to reduce binary size
985 KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
987 # Check for frame size exceeding threshold during prolog/epilog insertion
988 # when using lld < 13.0.0.
989 ifneq ($(CONFIG_FRAME_WARN),0)
990 ifeq ($(call test-lt, $(CONFIG_LLD_VERSION), 130000),y)
991 KBUILD_LDFLAGS += -plugin-opt=-warn-stack-size=$(CONFIG_FRAME_WARN)
997 KBUILD_CFLAGS += -fno-lto $(CC_FLAGS_LTO)
998 KBUILD_AFLAGS += -fno-lto
1002 ifdef CONFIG_CFI_CLANG
1003 CC_FLAGS_CFI := -fsanitize=kcfi
1004 KBUILD_CFLAGS += $(CC_FLAGS_CFI)
1008 ifneq ($(CONFIG_FUNCTION_ALIGNMENT),0)
1009 KBUILD_CFLAGS += -falign-functions=$(CONFIG_FUNCTION_ALIGNMENT)
1012 # arch Makefile may override CC so keep this after arch Makefile is included
1013 NOSTDINC_FLAGS += -nostdinc
1015 # warn about C99 declaration after statement
1016 KBUILD_CFLAGS += -Wdeclaration-after-statement
1018 # Variable Length Arrays (VLAs) should not be used anywhere in the kernel
1019 KBUILD_CFLAGS += -Wvla
1021 # disable pointer signed / unsigned warnings in gcc 4.0
1022 KBUILD_CFLAGS += -Wno-pointer-sign
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.
1027 KBUILD_CFLAGS += $(call cc-option, -Wcast-function-type)
1029 # disable stringop warnings in gcc 8+
1030 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
1032 # We'll want to enable this eventually, but it's not going away for 5.7 at least
1033 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
1035 # Another good warning that we'll want to enable eventually
1036 KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
1038 # Enabled with W=2, disabled by default as noisy
1039 ifdef CONFIG_CC_IS_GCC
1040 KBUILD_CFLAGS += -Wno-maybe-uninitialized
1043 # The allocators already balk at large sizes, so silence the compiler
1044 # warnings for bounds checks involving those possible values. While
1045 # -Wno-alloc-size-larger-than would normally be used here, earlier versions
1046 # of gcc (<9.1) weirdly don't handle the option correctly when _other_
1047 # warnings are produced (?!). Using -Walloc-size-larger-than=SIZE_MAX
1048 # doesn't work (as it is documented to), silently resolving to "0" prior to
1049 # version 9.1 (and producing an error more recently). Numeric values larger
1050 # than PTRDIFF_MAX also don't work prior to version 9.1, which are silently
1051 # ignored, continuing to default to PTRDIFF_MAX. So, left with no other
1052 # choice, we must perform a versioned check to disable this warning.
1053 # https://lore.kernel.org/lkml/20210824115859.187f272f@canb.auug.org.au
1054 KBUILD_CFLAGS-$(call gcc-min-version, 90100) += -Wno-alloc-size-larger-than
1055 KBUILD_CFLAGS += $(KBUILD_CFLAGS-y) $(CONFIG_CC_IMPLICIT_FALLTHROUGH)
1057 # disable invalid "can't wrap" optimizations for signed / pointers
1058 KBUILD_CFLAGS += -fno-strict-overflow
1060 # Make sure -fstack-check isn't enabled (like gentoo apparently did)
1061 KBUILD_CFLAGS += -fno-stack-check
1063 # conserve stack if available
1064 ifdef CONFIG_CC_IS_GCC
1065 KBUILD_CFLAGS += -fconserve-stack
1068 # Prohibit date/time macros, which would make the build non-deterministic
1069 KBUILD_CFLAGS += -Werror=date-time
1071 # enforce correct pointer usage
1072 KBUILD_CFLAGS += $(call cc-option,-Werror=incompatible-pointer-types)
1074 # Require designated initializers for all marked structures
1075 KBUILD_CFLAGS += $(call cc-option,-Werror=designated-init)
1077 # change __FILE__ to the relative path from the srctree
1078 KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
1080 # include additional Makefiles when needed
1081 include-y := scripts/Makefile.extrawarn
1082 include-$(CONFIG_DEBUG_INFO) += scripts/Makefile.debug
1083 include-$(CONFIG_KASAN) += scripts/Makefile.kasan
1084 include-$(CONFIG_KCSAN) += scripts/Makefile.kcsan
1085 include-$(CONFIG_KMSAN) += scripts/Makefile.kmsan
1086 include-$(CONFIG_UBSAN) += scripts/Makefile.ubsan
1087 include-$(CONFIG_KCOV) += scripts/Makefile.kcov
1088 include-$(CONFIG_RANDSTRUCT) += scripts/Makefile.randstruct
1089 include-$(CONFIG_GCC_PLUGINS) += scripts/Makefile.gcc-plugins
1091 include $(addprefix $(srctree)/, $(include-y))
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.
1097 # Add user supplied CPPFLAGS, AFLAGS, CFLAGS and RUSTFLAGS as the last assignments
1098 KBUILD_CPPFLAGS += $(KCPPFLAGS)
1099 KBUILD_AFLAGS += $(KAFLAGS)
1100 KBUILD_CFLAGS += $(KCFLAGS)
1101 KBUILD_RUSTFLAGS += $(KRUSTFLAGS)
1103 KBUILD_LDFLAGS_MODULE += --build-id=sha1
1104 LDFLAGS_vmlinux += --build-id=sha1
1106 KBUILD_LDFLAGS += -z noexecstack
1107 ifeq ($(CONFIG_LD_IS_BFD),y)
1108 KBUILD_LDFLAGS += $(call ld-option,--no-warn-rwx-segments)
1111 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1112 LDFLAGS_vmlinux += -X
1115 ifeq ($(CONFIG_RELR),y)
1116 # ld.lld before 15 did not support -z pack-relative-relocs.
1117 LDFLAGS_vmlinux += $(call ld-option,--pack-dyn-relocs=relr,-z pack-relative-relocs)
1120 # We never want expected sections to be placed heuristically by the
1121 # linker. All sections should be explicitly named in the linker script.
1122 ifdef CONFIG_LD_ORPHAN_WARN
1123 LDFLAGS_vmlinux += --orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL)
1126 # Align the bit size of userspace programs with the kernel
1127 KBUILD_USERCFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1128 KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1130 # make the checker run with the right architecture
1131 CHECKFLAGS += --arch=$(ARCH)
1133 # insure the checker run with the right endianness
1134 CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1136 # the checker needs the correct machine size
1137 CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1139 # Default kernel image to build when no specific target is given.
1140 # KBUILD_IMAGE may be overruled on the command line or
1141 # set in the environment
1142 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
1143 # this default value
1144 export KBUILD_IMAGE ?= vmlinux
1147 # INSTALL_PATH specifies where to place the updated kernel and system map
1148 # images. Default is /boot, but you can set it to other values
1149 export INSTALL_PATH ?= /boot
1152 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1153 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1154 # an argument if needed. Otherwise it defaults to the kernel install path
1156 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1159 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1160 # relocations required by build roots. This is not defined in the
1161 # makefile but the argument can be passed to make if needed.
1164 MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1169 export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
1170 export MODORDER := $(extmod_prefix)modules.order
1171 export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
1173 ifeq ($(KBUILD_EXTMOD),)
1176 clean-dirs := $(sort . Documentation \
1177 $(patsubst %/,%,$(filter %/, $(core-) \
1178 $(drivers-) $(libs-))))
1180 export ARCH_CORE := $(core-y)
1181 export ARCH_LIB := $(filter %/, $(libs-y))
1182 export ARCH_DRIVERS := $(drivers-y) $(drivers-m)
1183 # Externally visible symbols (used by link-vmlinux.sh)
1185 KBUILD_VMLINUX_OBJS := ./built-in.a
1186 ifdef CONFIG_MODULES
1187 KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1188 KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1190 KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1193 export KBUILD_VMLINUX_LIBS
1194 export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
1196 # Recurse until adjust_autoksyms.sh is satisfied
1197 PHONY += autoksyms_recursive
1198 ifdef CONFIG_TRIM_UNUSED_KSYMS
1199 # For the kernel to actually contain only the needed exported symbols,
1200 # we have to build modules as well to determine what those symbols are.
1201 # (this can be evaluated only once include/config/auto.conf has been included)
1204 autoksyms_recursive: $(build-dir) modules.order
1205 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1206 "$(MAKE) -f $(srctree)/Makefile autoksyms_recursive"
1209 autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1211 quiet_cmd_autoksyms_h = GEN $@
1212 cmd_autoksyms_h = mkdir -p $(dir $@); \
1213 $(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@
1216 $(call cmd,autoksyms_h)
1218 # '$(AR) mPi' needs 'T' to workaround the bug of llvm-ar <= 14
1219 quiet_cmd_ar_vmlinux.a = AR $@
1220 cmd_ar_vmlinux.a = \
1222 $(AR) cDPrST $@ $(KBUILD_VMLINUX_OBJS); \
1223 $(AR) mPiT $$($(AR) t $@ | sed -n 1p) $@ $$($(AR) t $@ | grep -F -f $(srctree)/scripts/head-object-list.txt)
1225 targets += vmlinux.a
1226 vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt autoksyms_recursive FORCE
1227 $(call if_changed,ar_vmlinux.a)
1230 vmlinux_o: vmlinux.a $(KBUILD_VMLINUX_LIBS)
1231 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o
1233 vmlinux.o modules.builtin.modinfo modules.builtin: vmlinux_o
1237 # LDFLAGS_vmlinux in the top Makefile defines linker flags for the top vmlinux,
1238 # not for decompressors. LDFLAGS_vmlinux in arch/*/boot/compressed/Makefile is
1239 # unrelated; the decompressors just happen to have the same base name,
1240 # arch/*/boot/compressed/vmlinux.
1241 # Export LDFLAGS_vmlinux only to scripts/Makefile.vmlinux.
1243 # _LDFLAGS_vmlinux is a workaround for the 'private export' bug:
1244 # https://savannah.gnu.org/bugs/?61463
1245 # For Make > 4.4, the following simple code will work:
1246 # vmlinux: private export LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1247 vmlinux: private _LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1248 vmlinux: export LDFLAGS_vmlinux = $(_LDFLAGS_vmlinux)
1249 vmlinux: vmlinux.o $(KBUILD_LDS) modpost
1250 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux
1252 # The actual objects are generated when descending,
1253 # make sure no implicit rule kicks in
1254 $(sort $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)): . ;
1256 ifeq ($(origin KERNELRELEASE),file)
1257 filechk_kernel.release = $(srctree)/scripts/setlocalversion $(srctree)
1259 filechk_kernel.release = echo $(KERNELRELEASE)
1262 # Store (new) KERNELRELEASE string in include/config/kernel.release
1263 include/config/kernel.release: FORCE
1264 $(call filechk,kernel.release)
1266 # Additional helpers built in scripts/
1267 # Carefully list dependencies so we do not try to build scripts twice
1270 scripts: scripts_basic scripts_dtc
1271 $(Q)$(MAKE) $(build)=$(@)
1273 # Things we need to do before we recursively start building the kernel
1274 # or the modules are listed in "prepare".
1275 # A multi level approach is used. prepareN is processed before prepareN-1.
1276 # archprepare is used in arch Makefiles and when processed asm symlink,
1277 # version.h and scripts_basic is processed / created.
1279 PHONY += prepare archprepare
1281 archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1282 asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h \
1283 include/generated/compile.h include/generated/autoconf.h remove-stale-files
1285 prepare0: archprepare
1286 $(Q)$(MAKE) $(build)=scripts/mod
1287 $(Q)$(MAKE) $(build)=. prepare
1289 # All the preparing..
1292 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh -v
1293 $(Q)$(MAKE) $(build)=rust
1296 PHONY += remove-stale-files
1298 $(Q)$(srctree)/scripts/remove-stale-files
1300 # Support for using generic headers in asm-generic
1301 asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1303 PHONY += asm-generic uapi-asm-generic
1304 asm-generic: uapi-asm-generic
1305 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1306 generic=include/asm-generic
1308 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1309 generic=include/uapi/asm-generic
1311 # Generate some files
1312 # ---------------------------------------------------------------------------
1314 # KERNELRELEASE can change from a few different places, meaning version.h
1315 # needs to be updated, so this check is forced on all builds
1318 define filechk_utsrelease.h
1319 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1320 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1323 echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1326 define filechk_version.h
1327 if [ $(SUBLEVEL) -gt 255 ]; then \
1328 echo \#define LINUX_VERSION_CODE $(shell \
1329 expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1331 echo \#define LINUX_VERSION_CODE $(shell \
1332 expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1334 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + \
1335 ((c) > 255 ? 255 : (c)))'; \
1336 echo \#define LINUX_VERSION_MAJOR $(VERSION); \
1337 echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL); \
1338 echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1341 $(version_h): PATCHLEVEL := $(or $(PATCHLEVEL), 0)
1342 $(version_h): SUBLEVEL := $(or $(SUBLEVEL), 0)
1344 $(call filechk,version.h)
1346 include/generated/utsrelease.h: include/config/kernel.release FORCE
1347 $(call filechk,utsrelease.h)
1349 filechk_compile.h = $(srctree)/scripts/mkcompile_h \
1350 "$(UTS_MACHINE)" "$(CONFIG_CC_VERSION_TEXT)" "$(LD)"
1352 include/generated/compile.h: FORCE
1353 $(call filechk,compile.h)
1357 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1358 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1360 # ---------------------------------------------------------------------------
1363 #Default location for installed headers
1364 export INSTALL_HDR_PATH = $(objtree)/usr
1366 quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1367 cmd_headers_install = \
1368 mkdir -p $(INSTALL_HDR_PATH); \
1369 rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1370 usr/include $(INSTALL_HDR_PATH)
1372 PHONY += headers_install
1373 headers_install: headers
1374 $(call cmd,headers_install)
1376 PHONY += archheaders archscripts
1378 hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1381 headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1382 $(if $(filter um, $(SRCARCH)), $(error Headers not exportable for UML))
1383 $(Q)$(MAKE) $(hdr-inst)=include/uapi
1384 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1386 ifdef CONFIG_HEADERS_INSTALL
1390 PHONY += scripts_unifdef
1391 scripts_unifdef: scripts_basic
1392 $(Q)$(MAKE) $(build)=scripts scripts/unifdef
1394 # ---------------------------------------------------------------------------
1397 # Many distributions have the custom install script, /sbin/installkernel.
1398 # If DKMS is installed, 'make install' will eventually recurse back
1399 # to this Makefile to build and install external modules.
1400 # Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
1402 quiet_cmd_install = INSTALL $(INSTALL_PATH)
1403 cmd_install = unset sub_make_done; $(srctree)/scripts/install.sh
1405 # ---------------------------------------------------------------------------
1408 ifdef CONFIG_OBJTOOL
1409 prepare: tools/objtool
1413 ifdef CONFIG_DEBUG_INFO_BTF
1414 prepare: tools/bpf/resolve_btfids
1418 PHONY += resolve_btfids_clean
1420 resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1422 # tools/bpf/resolve_btfids directory might not exist
1423 # in output directory, skip its clean in that case
1424 resolve_btfids_clean:
1425 ifneq ($(wildcard $(resolve_btfids_O)),)
1426 $(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1429 # Clear a bunch of variables before executing the submake
1430 ifeq ($(quiet),silent_)
1435 $(Q)mkdir -p $(objtree)/tools
1436 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1439 $(Q)mkdir -p $(objtree)/tools
1440 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1442 # ---------------------------------------------------------------------------
1447 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1449 kselftest-%: headers FORCE
1450 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1452 PHONY += kselftest-merge
1454 $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1455 $(Q)find $(srctree)/tools/testing/selftests -name config | \
1456 xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1457 $(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1459 # ---------------------------------------------------------------------------
1462 ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1463 dtstree := arch/$(SRCARCH)/boot/dts
1469 $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1471 %.dtbo: dtbs_prepare
1472 $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1474 PHONY += dtbs dtbs_prepare dtbs_install dtbs_check
1476 $(Q)$(MAKE) $(build)=$(dtstree)
1478 # include/config/kernel.release is actually needed when installing DTBs because
1479 # INSTALL_DTBS_PATH contains $(KERNELRELEASE). However, we do not want to make
1480 # dtbs_install depend on it as dtbs_install may run as root.
1481 dtbs_prepare: include/config/kernel.release scripts_dtc
1483 ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1487 ifneq ($(CHECK_DTBS),)
1488 dtbs_prepare: dt_binding_check
1494 $(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1496 ifdef CONFIG_OF_EARLY_FLATTREE
1502 PHONY += scripts_dtc
1503 scripts_dtc: scripts_basic
1504 $(Q)$(MAKE) $(build)=scripts/dtc
1506 ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1507 export CHECK_DT_BINDING=y
1510 PHONY += dt_binding_check
1511 dt_binding_check: scripts_dtc
1512 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1514 PHONY += dt_compatible_check
1515 dt_compatible_check: dt_binding_check
1516 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1518 # ---------------------------------------------------------------------------
1521 ifdef CONFIG_MODULES
1523 # By default, build modules as well
1527 # When we're building modules with modversions, we need to consider
1528 # the built-in objects during the descend as well, in order to
1529 # make sure the checksums are up to date before we record them.
1530 ifdef CONFIG_MODVERSIONS
1537 # *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFO_BTF_MODULES
1539 ifdef CONFIG_DEBUG_INFO_BTF_MODULES
1544 modules: modules_prepare
1546 # Target to prepare building external modules
1547 modules_prepare: prepare
1548 $(Q)$(MAKE) $(build)=scripts scripts/module.lds
1550 export modules_sign_only :=
1552 ifeq ($(CONFIG_MODULE_SIG),y)
1553 PHONY += modules_sign
1554 modules_sign: modules_install
1557 # modules_sign is a subset of modules_install.
1558 # 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1559 ifeq ($(filter modules_install,$(MAKECMDGOALS)),)
1560 modules_sign_only := y
1565 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
1566 modinst_pre := __modinst_pre
1569 modules_install: $(modinst_pre)
1570 PHONY += __modinst_pre
1572 @rm -rf $(MODLIB)/kernel
1573 @rm -f $(MODLIB)/source
1574 @mkdir -p $(MODLIB)/kernel
1575 @ln -s $(abspath $(srctree)) $(MODLIB)/source
1576 @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
1577 rm -f $(MODLIB)/build ; \
1578 ln -s $(CURDIR) $(MODLIB)/build ; \
1580 @sed 's:^\(.*\)\.o$$:kernel/\1.ko:' modules.order > $(MODLIB)/modules.order
1581 @cp -f modules.builtin $(MODLIB)/
1582 @cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
1584 endif # CONFIG_MODULES
1587 # Cleaning is done on three levels.
1588 # make clean Delete most generated files
1589 # Leave enough to build external modules
1590 # make mrproper Delete the current configuration, and all generated files
1591 # make distclean Remove editor backup files, patch leftover files and the like
1593 # Directories & files removed with 'make clean'
1594 CLEAN_FILES += include/ksym vmlinux.symvers modules-only.symvers \
1595 modules.builtin modules.builtin.modinfo modules.nsdeps \
1596 compile_commands.json .thinlto-cache rust/test rust/doc \
1597 rust-project.json .vmlinux.objs .vmlinux.export.c
1599 # Directories & files removed with 'make mrproper'
1600 MRPROPER_FILES += include/config include/generated \
1601 arch/$(SRCARCH)/include/generated .objdiff \
1602 debian snap tar-install \
1603 .config .config.old .version \
1605 certs/signing_key.pem \
1611 # clean - Delete most, but leave enough to build external modules
1613 clean: rm-files := $(CLEAN_FILES)
1615 PHONY += archclean vmlinuxclean
1618 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1619 $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1621 clean: archclean vmlinuxclean resolve_btfids_clean
1623 # mrproper - Delete all generated files, including .config
1625 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1626 mrproper-dirs := $(addprefix _mrproper_,scripts)
1628 PHONY += $(mrproper-dirs) mrproper
1630 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1632 mrproper: clean $(mrproper-dirs)
1634 @find . $(RCS_FIND_IGNORE) \
1635 \( -name '*.rmeta' \) \
1636 -type f -print | xargs rm -f
1643 @find . $(RCS_FIND_IGNORE) \
1644 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1645 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1646 -o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1647 -o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1648 -type f -print | xargs rm -f
1651 # Packaging of the kernel to various formats
1652 # ---------------------------------------------------------------------------
1655 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1656 %pkg: include/config/kernel.release FORCE
1657 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1659 # Brief documentation of the typical targets used
1660 # ---------------------------------------------------------------------------
1662 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1663 boards := $(sort $(notdir $(boards)))
1664 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1665 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1669 @echo 'Cleaning targets:'
1670 @echo ' clean - Remove most generated files but keep the config and'
1671 @echo ' enough build support to build external modules'
1672 @echo ' mrproper - Remove all generated files + config + various backup files'
1673 @echo ' distclean - mrproper + remove editor backup and patch files'
1675 @echo 'Configuration targets:'
1676 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1678 @echo 'Other generic targets:'
1679 @echo ' all - Build all targets marked with [*]'
1680 @echo '* vmlinux - Build the bare kernel'
1681 @echo '* modules - Build all modules'
1682 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1683 @echo ' dir/ - Build all files in dir and below'
1684 @echo ' dir/file.[ois] - Build specified target only'
1685 @echo ' dir/file.ll - Build the LLVM assembly file'
1686 @echo ' (requires compiler support for LLVM assembly generation)'
1687 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1688 @echo ' (requires a recent binutils and recent build (System.map))'
1689 @echo ' dir/file.ko - Build module including final link'
1690 @echo ' modules_prepare - Set up for building external modules'
1691 @echo ' tags/TAGS - Generate tags file for editors'
1692 @echo ' cscope - Generate cscope index'
1693 @echo ' gtags - Generate GNU GLOBAL index'
1694 @echo ' kernelrelease - Output the release version string (use with make -s)'
1695 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1696 @echo ' image_name - Output the image name (use with make -s)'
1697 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1698 echo ' (default: $(INSTALL_HDR_PATH))'; \
1700 @echo 'Static analysers:'
1701 @echo ' checkstack - Generate a list of stack hogs'
1702 @echo ' versioncheck - Sanity check on version.h usage'
1703 @echo ' includecheck - Check for duplicate included header files'
1704 @echo ' export_report - List the usages of all exported symbols'
1705 @echo ' headerdep - Detect inclusion cycles in headers'
1706 @echo ' coccicheck - Check with Coccinelle'
1707 @echo ' clang-analyzer - Check with clang static analyzer'
1708 @echo ' clang-tidy - Check with clang-tidy'
1711 @echo ' nsdeps - Generate missing symbol namespace dependencies'
1713 @echo 'Kernel selftest:'
1714 @echo ' kselftest - Build and run kernel selftest'
1715 @echo ' Build, install, and boot kernel before'
1716 @echo ' running kselftest on it'
1717 @echo ' Run as root for full coverage'
1718 @echo ' kselftest-all - Build kernel selftest'
1719 @echo ' kselftest-install - Build and install kernel selftest'
1720 @echo ' kselftest-clean - Remove all generated kselftest files'
1721 @echo ' kselftest-merge - Merge all the config dependencies of'
1722 @echo ' kselftest to existing .config.'
1724 @echo 'Rust targets:'
1725 @echo ' rustavailable - Checks whether the Rust toolchain is'
1726 @echo ' available and, if not, explains why.'
1727 @echo ' rustfmt - Reformat all the Rust code in the kernel'
1728 @echo ' rustfmtcheck - Checks if all the Rust code in the kernel'
1729 @echo ' is formatted, printing a diff otherwise.'
1730 @echo ' rustdoc - Generate Rust documentation'
1731 @echo ' (requires kernel .config)'
1732 @echo ' rusttest - Runs the Rust tests'
1733 @echo ' (requires kernel .config; downloads external repos)'
1734 @echo ' rust-analyzer - Generate rust-project.json rust-analyzer support file'
1735 @echo ' (requires kernel .config)'
1736 @echo ' dir/file.[os] - Build specified target only'
1737 @echo ' dir/file.rsi - Build macro expanded source, similar to C preprocessing.'
1738 @echo ' Run with RUSTFMT=n to skip reformatting if needed.'
1739 @echo ' The output is not intended to be compilable.'
1740 @echo ' dir/file.ll - Build the LLVM assembly file'
1743 echo 'Devicetree:'; \
1744 echo '* dtbs - Build device tree blobs for enabled boards'; \
1745 echo ' dtbs_install - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1746 echo ' dt_binding_check - Validate device tree binding documents'; \
1747 echo ' dtbs_check - Validate device tree source files';\
1750 @echo 'Userspace tools targets:'
1751 @echo ' use "make tools/help"'
1752 @echo ' or "cd tools; make help"'
1754 @echo 'Kernel packaging:'
1755 @$(MAKE) -f $(srctree)/scripts/Makefile.package help
1757 @echo 'Documentation targets:'
1758 @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1760 @echo 'Architecture specific targets ($(SRCARCH)):'
1762 echo ' No architecture specific help defined for $(SRCARCH)')
1765 $(foreach b, $(boards), \
1766 printf " %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1768 @$(if $(board-dirs), \
1769 $(foreach b, $(board-dirs), \
1770 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1771 printf " %-16s - Show all of the above\\n" help-boards; \
1774 @echo ' make V=n [targets] 1: verbose build'
1775 @echo ' 2: give reason for rebuild of target'
1776 @echo ' V=1 and V=2 can be combined with V=12'
1777 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1778 @echo ' make C=1 [targets] Check re-compiled c source with $$CHECK'
1779 @echo ' (sparse by default)'
1780 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1781 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1782 @echo ' make W=n [targets] Enable extra build checks, n=1,2,3 where'
1783 @echo ' 1: warnings which may be relevant and do not occur too often'
1784 @echo ' 2: warnings which occur quite often but may still be relevant'
1785 @echo ' 3: more obscure warnings, can most likely be ignored'
1786 @echo ' e: warnings are being treated as errors'
1787 @echo ' Multiple levels can be combined with W=12 or W=123'
1789 echo ' make CHECK_DTBS=1 [targets] Check all generated dtb files against schema'; \
1790 echo ' This can be applied both to "dtbs" and to individual "foo.dtb" targets' ; \
1793 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1794 @echo 'For further info see the ./README file'
1797 help-board-dirs := $(addprefix help-,$(board-dirs))
1799 help-boards: $(help-board-dirs)
1801 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1803 $(help-board-dirs): help-%:
1804 @echo 'Architecture specific targets ($(SRCARCH) $*):'
1805 @$(if $(boards-per-dir), \
1806 $(foreach b, $(boards-per-dir), \
1807 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1811 # Documentation targets
1812 # ---------------------------------------------------------------------------
1813 DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1814 linkcheckdocs dochelp refcheckdocs texinfodocs infodocs
1815 PHONY += $(DOC_TARGETS)
1817 $(Q)$(MAKE) $(build)=Documentation $@
1821 # ---------------------------------------------------------------------------
1823 # "Is Rust available?" target
1824 PHONY += rustavailable
1826 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh -v && echo "Rust is available!"
1828 # Documentation target
1830 # Using the singular to avoid running afoul of `no-dot-config-targets`.
1833 $(Q)$(MAKE) $(build)=rust $@
1838 $(Q)$(MAKE) $(build)=rust $@
1840 # Formatting targets
1841 PHONY += rustfmt rustfmtcheck
1843 # We skip `rust/alloc` since we want to minimize the diff w.r.t. upstream.
1845 # We match using absolute paths since `find` does not resolve them
1846 # when matching, which is a problem when e.g. `srctree` is `..`.
1847 # We `grep` afterwards in order to remove the directory entry itself.
1849 $(Q)find $(abs_srctree) -type f -name '*.rs' \
1850 -o -path $(abs_srctree)/rust/alloc -prune \
1851 -o -path $(abs_objtree)/rust/test -prune \
1852 | grep -Fv $(abs_srctree)/rust/alloc \
1853 | grep -Fv $(abs_objtree)/rust/test \
1854 | grep -Fv generated \
1855 | xargs $(RUSTFMT) $(rustfmt_flags)
1857 rustfmtcheck: rustfmt_flags = --check
1858 rustfmtcheck: rustfmt
1860 # IDE support targets
1861 PHONY += rust-analyzer
1863 $(Q)$(MAKE) $(build)=rust $@
1866 # ---------------------------------------------------------------------------
1870 $(Q)$(srctree)/scripts/misc-check
1874 PHONY += scripts_gdb
1875 scripts_gdb: prepare0
1876 $(Q)$(MAKE) $(build)=scripts/gdb
1877 $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1879 ifdef CONFIG_GDB_SCRIPTS
1883 else # KBUILD_EXTMOD
1885 filechk_kernel.release = echo $(KERNELRELEASE)
1888 # External module support.
1889 # When building external modules the kernel used as basis is considered
1890 # read-only, and no consistency checks are made and the make
1891 # system is not used on the basis kernel. If updates are required
1892 # in the basis kernel ordinary make commands (without M=...) must be used.
1894 # We are always building only modules.
1898 build-dir := $(KBUILD_EXTMOD)
1900 compile_commands.json: $(extmod_prefix)compile_commands.json
1901 PHONY += compile_commands.json
1903 clean-dirs := $(KBUILD_EXTMOD)
1904 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1905 $(KBUILD_EXTMOD)/compile_commands.json $(KBUILD_EXTMOD)/.thinlto-cache
1908 # now expand this into a simple variable to reduce the cost of shell evaluations
1909 prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT)
1911 @if [ "$(CC_VERSION_TEXT)" != "$(CONFIG_CC_VERSION_TEXT)" ]; then \
1912 echo >&2 "warning: the compiler differs from the one used to build the kernel"; \
1913 echo >&2 " The kernel was built by: $(CONFIG_CC_VERSION_TEXT)"; \
1914 echo >&2 " You are using: $(CC_VERSION_TEXT)"; \
1919 @echo ' Building external modules.'
1920 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1922 @echo ' modules - default target, build the module(s)'
1923 @echo ' modules_install - install the module'
1924 @echo ' clean - remove generated files in module directory only'
1927 endif # KBUILD_EXTMOD
1929 # ---------------------------------------------------------------------------
1932 PHONY += modules modules_install modules_prepare
1934 ifdef CONFIG_MODULES
1936 $(MODORDER): $(build-dir)
1939 # KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
1940 # This is solely useful to speed up test compiles.
1942 ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1943 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1946 PHONY += modules_check
1947 modules_check: $(MODORDER)
1948 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1950 quiet_cmd_depmod = DEPMOD $(MODLIB)
1951 cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1955 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1958 else # CONFIG_MODULES
1960 # Modules not configured
1961 # ---------------------------------------------------------------------------
1963 modules modules_install:
1965 @echo >&2 '*** The present kernel configuration has modules disabled.'
1966 @echo >&2 '*** To use the module feature, please run "make menuconfig" etc.'
1967 @echo >&2 '*** to enable CONFIG_MODULES.'
1973 endif # CONFIG_MODULES
1976 modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \
1977 $(if $(KBUILD_MODULES), modules_check)
1978 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1981 # ---------------------------------------------------------------------------
1982 # To build individual files in subdirectories, you can do like this:
1984 # make foo/bar/baz.s
1986 # The supported suffixes for single-target are listed in 'single-targets'
1988 # To build only under specific subdirectories, you can do like this:
1994 # .ko is special because modpost is needed
1995 single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1996 single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \
1997 $(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko)))
1999 $(single-ko): single_modules
2001 $(single-no-ko): $(build-dir)
2004 # Remove MODORDER when done because it is not the real one.
2005 PHONY += single_modules
2006 single_modules: $(single-no-ko) modules_prepare
2007 $(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$(m:%.ko=%.o);) } > $(MODORDER)
2008 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
2009 ifneq ($(KBUILD_MODPOST_NOFINAL),1)
2010 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
2012 $(Q)rm -f $(MODORDER)
2014 single-goals := $(addprefix $(build-dir)/, $(single-no-ko))
2020 # Preset locale variables to speed up the build process. Limit locale
2021 # tweaks to this spot to avoid wrong language settings when running
2022 # make menuconfig etc.
2023 # Error messages still appears in the original language
2024 PHONY += $(build-dir)
2025 $(build-dir): prepare
2026 $(Q)$(MAKE) $(build)=$@ need-builtin=1 need-modorder=1 $(single-goals)
2028 clean-dirs := $(addprefix _clean_, $(clean-dirs))
2029 PHONY += $(clean-dirs) clean
2031 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
2033 clean: $(clean-dirs)
2035 @find $(or $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
2036 \( -name '*.[aios]' -o -name '*.rsi' -o -name '*.ko' -o -name '.*.cmd' \
2038 -o -name '*.dtb' -o -name '*.dtbo' \
2039 -o -name '*.dtb.S' -o -name '*.dtbo.S' \
2040 -o -name '*.dt.yaml' \
2041 -o -name '*.dwo' -o -name '*.lst' \
2042 -o -name '*.su' -o -name '*.mod' -o -name '*.usyms' \
2043 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
2044 -o -name '*.lex.c' -o -name '*.tab.[ch]' \
2045 -o -name '*.asn1.[ch]' \
2046 -o -name '*.symtypes' -o -name 'modules.order' \
2047 -o -name '*.c.[012]*.*' \
2050 -o -name '*.*.symversions' \) -type f -print \
2051 -o -name '.tmp_*' -print \
2054 # Generate tags for editors
2055 # ---------------------------------------------------------------------------
2056 quiet_cmd_tags = GEN $@
2057 cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
2059 tags TAGS cscope gtags: FORCE
2062 # Script to generate missing namespace dependencies
2063 # ---------------------------------------------------------------------------
2066 nsdeps: export KBUILD_NSDEPS=1
2068 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
2071 # ---------------------------------------------------------------------------
2073 quiet_cmd_gen_compile_commands = GEN $@
2074 cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
2076 $(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
2077 $(if $(KBUILD_EXTMOD),, vmlinux.a $(KBUILD_VMLINUX_LIBS)) \
2078 $(if $(CONFIG_MODULES), $(MODORDER)) FORCE
2079 $(call if_changed,gen_compile_commands)
2081 targets += $(extmod_prefix)compile_commands.json
2083 PHONY += clang-tidy clang-analyzer
2085 ifdef CONFIG_CC_IS_CLANG
2086 quiet_cmd_clang_tools = CHECK $<
2087 cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
2089 clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
2090 $(call cmd,clang_tools)
2092 clang-tidy clang-analyzer:
2093 @echo "$@ requires CC=clang" >&2
2097 # Scripts to check various things for consistency
2098 # ---------------------------------------------------------------------------
2100 PHONY += includecheck versioncheck coccicheck export_report
2103 find $(srctree)/* $(RCS_FIND_IGNORE) \
2104 -name '*.[hcS]' -type f -print | sort \
2105 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
2108 find $(srctree)/* $(RCS_FIND_IGNORE) \
2109 -name '*.[hcS]' -type f -print | sort \
2110 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
2113 $(Q)$(BASH) $(srctree)/scripts/$@
2116 $(PERL) $(srctree)/scripts/export_report.pl
2118 PHONY += checkstack kernelrelease kernelversion image_name
2120 # UML needs a little special treatment here. It wants to use the host
2121 # toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
2122 # else wants $(ARCH), including people doing cross-builds, which means
2123 # that $(SUBARCH) doesn't work here.
2125 CHECKSTACK_ARCH := $(SUBARCH)
2127 CHECKSTACK_ARCH := $(ARCH)
2130 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
2131 $(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
2134 @$(filechk_kernel.release)
2137 @echo $(KERNELVERSION)
2140 @echo $(KBUILD_IMAGE)
2142 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
2143 cmd_rmfiles = rm -rf $(rm-files)
2145 # read saved command lines for existing targets
2146 existing-targets := $(wildcard $(sort $(targets)))
2148 -include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
2150 endif # config-build
2152 endif # need-sub-make
2157 # Declare the contents of the PHONY variable as phony. We keep that
2158 # information in a variable so we can use it in if_changed and friends.