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 $(if $(filter __%, $(MAKECMDGOALS)), \
15 $(error targets prefixed with '__' are only for internal use))
17 # That's our default target when none is given on the command line
21 # We are using a recursive build, so we need to do a little thinking
22 # to get the ordering right.
24 # Most importantly: sub-Makefiles should only ever modify files in
25 # their own directory. If in some directory we have a dependency on
26 # a file in another dir (which doesn't happen often, but it's often
27 # unavoidable when linking the built-in.a targets which finally
28 # turn into vmlinux), we will call a sub make in that other dir, and
29 # after that we are sure that everything which is in that other dir
32 # The only cases where we need to modify files which have global
33 # effects are thus separated out and done before the recursive
34 # descending is started. They are now explicitly listed as the
37 ifneq ($(sub_make_done),1)
39 # Do not use make's built-in rules and variables
40 # (this increases performance and avoids hard-to-debug behaviour)
43 # Avoid funny character set dependencies
47 export LC_COLLATE LC_NUMERIC
49 # Avoid interference with shell env settings
53 # ---------------------------------------------------------------------------
55 # Normally, we echo the whole command before executing it. By making
56 # that echo $($(quiet)$(cmd)), we now have the possibility to set
57 # $(quiet) to choose other forms of output instead, e.g.
59 # quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
60 # cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
62 # If $(quiet) is empty, the whole command will be printed.
63 # If it is set to "quiet_", only the short version will be printed.
64 # If it is set to "silent_", nothing will be printed at all, since
65 # the variable $(silent_cmd_cc_o_c) doesn't exist.
67 # A simple variant is to prefix commands with $(Q) - that's useful
68 # for commands that shall be hidden in non-verbose mode.
72 # If KBUILD_VERBOSE equals 0 then the above command will be hidden.
73 # If KBUILD_VERBOSE equals 1 then the above command is displayed.
74 # If KBUILD_VERBOSE equals 2 then give the reason why each target is rebuilt.
76 # To put more focus on warnings, be less verbose as default
77 # Use 'make V=1' to see the full commands
79 ifeq ("$(origin V)", "command line")
86 ifeq ($(KBUILD_VERBOSE),1)
94 # If the user is running make -s (silent mode), suppress echoing of
97 ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
102 export quiet Q KBUILD_VERBOSE
104 # Call a source code checker (by default, "sparse") as part of the
107 # Use 'make C=1' to enable checking of only re-compiled files.
108 # Use 'make C=2' to enable checking of *all* source files, regardless
109 # of whether they are re-compiled or not.
111 # See the file "Documentation/dev-tools/sparse.rst" for more details,
112 # including where to get the "sparse" utility.
114 ifeq ("$(origin C)", "command line")
115 KBUILD_CHECKSRC = $(C)
117 ifndef KBUILD_CHECKSRC
121 export KBUILD_CHECKSRC
123 # Enable "clippy" (a linter) as part of the Rust compilation.
125 # Use 'make CLIPPY=1' to enable it.
126 ifeq ("$(origin CLIPPY)", "command line")
127 KBUILD_CLIPPY := $(CLIPPY)
132 # Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
133 # directory of external module to build. Setting M= takes precedence.
134 ifeq ("$(origin M)", "command line")
135 KBUILD_EXTMOD := $(M)
138 $(if $(word 2, $(KBUILD_EXTMOD)), \
139 $(error building multiple external modules is not supported))
141 $(foreach x, % :, $(if $(findstring $x, $(KBUILD_EXTMOD)), \
142 $(error module directory path cannot contain '$x')))
144 # Remove trailing slashes
145 ifneq ($(filter %/, $(KBUILD_EXTMOD)),)
146 KBUILD_EXTMOD := $(shell dirname $(KBUILD_EXTMOD).)
151 # Kbuild will save output files in the current working directory.
152 # This does not need to match to the root of the kernel source tree.
154 # For example, you can do this:
156 # cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
158 # If you want to save output files in a different location, there are
159 # two syntaxes to specify it.
162 # Use "make O=dir/to/store/output/files/"
164 # 2) Set KBUILD_OUTPUT
165 # Set the environment variable KBUILD_OUTPUT to point to the output directory.
166 # export KBUILD_OUTPUT=dir/to/store/output/files/; make
168 # The O= assignment takes precedence over the KBUILD_OUTPUT environment
171 # Do we want to change the working directory?
172 ifeq ("$(origin O)", "command line")
173 KBUILD_OUTPUT := $(O)
176 ifneq ($(KBUILD_OUTPUT),)
177 # Make's built-in functions such as $(abspath ...), $(realpath ...) cannot
178 # expand a shell special character '~'. We use a somewhat tedious way here.
179 abs_objtree := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) && pwd)
180 $(if $(abs_objtree),, \
181 $(error failed to create output directory "$(KBUILD_OUTPUT)"))
183 # $(realpath ...) resolves symlinks
184 abs_objtree := $(realpath $(abs_objtree))
186 abs_objtree := $(CURDIR)
187 endif # ifneq ($(KBUILD_OUTPUT),)
189 ifeq ($(abs_objtree),$(CURDIR))
190 # Suppress "Entering directory ..." unless we are changing the work directory.
191 MAKEFLAGS += --no-print-directory
196 this-makefile := $(lastword $(MAKEFILE_LIST))
197 abs_srctree := $(realpath $(dir $(this-makefile)))
199 ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
200 $(error source directory cannot contain spaces or colons)
203 ifneq ($(abs_srctree),$(abs_objtree))
204 # Look for make include files relative to root of kernel src
206 # --included-dir is added for backward compatibility, but you should not rely on
207 # it. Please add $(srctree)/ prefix to include Makefiles in the source tree.
208 MAKEFLAGS += --include-dir=$(abs_srctree)
211 ifneq ($(filter 3.%,$(MAKE_VERSION)),)
212 # 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
213 # We need to invoke sub-make to avoid implicit rules in the top Makefile.
215 # Cancel implicit rules for this Makefile.
219 export abs_srctree abs_objtree
220 export sub_make_done := 1
222 ifeq ($(need-sub-make),1)
224 PHONY += $(MAKECMDGOALS) __sub-make
226 $(filter-out $(this-makefile), $(MAKECMDGOALS)) __all: __sub-make
229 # Invoke a second make in the output directory, passing relevant variables
231 $(Q)$(MAKE) -C $(abs_objtree) -f $(abs_srctree)/Makefile $(MAKECMDGOALS)
233 endif # need-sub-make
234 endif # sub_make_done
236 # We process the rest of the Makefile if this is the final invocation of make
237 ifeq ($(need-sub-make),)
239 # Do not print "Entering directory ...",
240 # but we want to display it when entering to the output directory
241 # so that IDEs/editors are able to understand relative filenames.
242 MAKEFLAGS += --no-print-directory
244 ifeq ($(abs_srctree),$(abs_objtree))
245 # building in the source tree
247 building_out_of_srctree :=
249 ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
250 # building in a subdirectory of the source tree
253 srctree := $(abs_srctree)
255 building_out_of_srctree := 1
258 ifneq ($(KBUILD_ABS_SRCTREE),)
259 srctree := $(abs_srctree)
265 export building_out_of_srctree srctree objtree VPATH
267 # To make sure we do not include .config for any of the *config targets
268 # catch them early, and hand them over to scripts/kconfig/Makefile
269 # It is allowed to specify more targets when calling make, including
270 # mixing *config targets and build targets.
271 # For example 'make oldconfig all'.
272 # Detect when mixed targets is specified, and make a second invocation
273 # of make so .config is not included in this case either (for *config).
275 version_h := include/generated/uapi/linux/version.h
277 clean-targets := %clean mrproper cleandocs
278 no-dot-config-targets := $(clean-targets) \
279 cscope gtags TAGS tags help% %docs check% coccicheck \
280 $(version_h) headers headers_% archheaders archscripts \
281 %asm-generic kernelversion %src-pkg dt_binding_check \
282 outputmakefile rustavailable rustfmt rustfmtcheck
283 # Installation targets should not require compiler. Unfortunately, vdso_install
284 # is an exception where build artifacts may be updated. This must be fixed.
285 no-compiler-targets := $(no-dot-config-targets) install dtbs_install \
286 headers_install modules_install kernelrelease image_name
287 no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease \
289 single-targets := %.a %.i %.rsi %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
298 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
299 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
304 ifneq ($(filter $(no-compiler-targets), $(MAKECMDGOALS)),)
305 ifeq ($(filter-out $(no-compiler-targets), $(MAKECMDGOALS)),)
310 ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
311 ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
316 ifneq ($(KBUILD_EXTMOD),)
320 ifeq ($(KBUILD_EXTMOD),)
321 ifneq ($(filter %config,$(MAKECMDGOALS)),)
323 ifneq ($(words $(MAKECMDGOALS)),1)
329 # We cannot build single targets and the others at the same time
330 ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
332 ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
337 # For "make -j clean all", "make -j mrproper defconfig all", etc.
338 ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
339 ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
344 # install and modules_install need also be processed one by one
345 ifneq ($(filter install,$(MAKECMDGOALS)),)
346 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
352 # ===========================================================================
353 # We're called with mixed targets (*config and build targets).
354 # Handle them one by one.
356 PHONY += $(MAKECMDGOALS) __build_one_by_one
358 $(MAKECMDGOALS): __build_one_by_one
363 for i in $(MAKECMDGOALS); do \
364 $(MAKE) -f $(srctree)/Makefile $$i; \
369 include $(srctree)/scripts/Kbuild.include
371 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
372 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
373 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
374 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
376 include $(srctree)/scripts/subarch.include
378 # Cross compiling and selecting different set of gcc/bin-utils
379 # ---------------------------------------------------------------------------
381 # When performing cross compilation for other architectures ARCH shall be set
382 # to the target architecture. (See arch/* for the possibilities).
383 # ARCH can be set during invocation of make:
385 # Another way is to have ARCH set in the environment.
386 # The default ARCH is the host where make is executed.
388 # CROSS_COMPILE specify the prefix used for all executables used
389 # during compilation. Only gcc and related bin-utils executables
390 # are prefixed with $(CROSS_COMPILE).
391 # CROSS_COMPILE can be set on the command line
392 # make CROSS_COMPILE=ia64-linux-
393 # Alternatively CROSS_COMPILE can be set in the environment.
394 # Default value for CROSS_COMPILE is not to prefix executables
395 # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
398 # Architecture as present in compile.h
399 UTS_MACHINE := $(ARCH)
402 # Additional ARCH settings for x86
406 ifeq ($(ARCH),x86_64)
410 # Additional ARCH settings for sparc
411 ifeq ($(ARCH),sparc32)
414 ifeq ($(ARCH),sparc64)
418 # Additional ARCH settings for parisc
419 ifeq ($(ARCH),parisc64)
423 export cross_compiling :=
424 ifneq ($(SRCARCH),$(SUBARCH))
428 KCONFIG_CONFIG ?= .config
429 export KCONFIG_CONFIG
431 # SHELL used by kbuild
434 HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
435 HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
436 HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
439 ifneq ($(filter %/,$(LLVM)),)
440 LLVM_PREFIX := $(LLVM)
441 else ifneq ($(filter -%,$(LLVM)),)
442 LLVM_SUFFIX := $(LLVM)
445 HOSTCC = $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
446 HOSTCXX = $(LLVM_PREFIX)clang++$(LLVM_SUFFIX)
452 HOSTPKG_CONFIG = pkg-config
454 KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
455 -O2 -fomit-frame-pointer -std=gnu11 \
456 -Wdeclaration-after-statement
457 KBUILD_USERCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(USERCFLAGS)
458 KBUILD_USERLDFLAGS := $(USERLDFLAGS)
460 # These flags apply to all Rust code in the tree, including the kernel and
462 export rust_common_flags := --edition=2021 \
463 -Zbinary_dep_depinfo=y \
464 -Dunsafe_op_in_unsafe_fn -Drust_2018_idioms \
465 -Dunreachable_pub -Dnon_ascii_idents \
467 -Drustdoc::missing_crate_level_docs \
468 -Dclippy::correctness -Dclippy::style \
469 -Dclippy::suspicious -Dclippy::complexity \
471 -Dclippy::let_unit_value -Dclippy::mut_mut \
472 -Dclippy::needless_bitwise_bool \
473 -Dclippy::needless_continue \
476 KBUILD_HOSTCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
477 KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
478 KBUILD_HOSTRUSTFLAGS := $(rust_common_flags) -O -Cstrip=debuginfo \
479 -Zallow-features= $(HOSTRUSTFLAGS)
480 KBUILD_HOSTLDFLAGS := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
481 KBUILD_HOSTLDLIBS := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
483 # Make variables (CC, etc...)
486 CC = $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
487 LD = $(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX)
488 AR = $(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX)
489 NM = $(LLVM_PREFIX)llvm-nm$(LLVM_SUFFIX)
490 OBJCOPY = $(LLVM_PREFIX)llvm-objcopy$(LLVM_SUFFIX)
491 OBJDUMP = $(LLVM_PREFIX)llvm-objdump$(LLVM_SUFFIX)
492 READELF = $(LLVM_PREFIX)llvm-readelf$(LLVM_SUFFIX)
493 STRIP = $(LLVM_PREFIX)llvm-strip$(LLVM_SUFFIX)
495 CC = $(CROSS_COMPILE)gcc
496 LD = $(CROSS_COMPILE)ld
497 AR = $(CROSS_COMPILE)ar
498 NM = $(CROSS_COMPILE)nm
499 OBJCOPY = $(CROSS_COMPILE)objcopy
500 OBJDUMP = $(CROSS_COMPILE)objdump
501 READELF = $(CROSS_COMPILE)readelf
502 STRIP = $(CROSS_COMPILE)strip
507 CLIPPY_DRIVER = clippy-driver
511 RESOLVE_BTFIDS = $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
515 INSTALLKERNEL := installkernel
529 PAHOLE_FLAGS = $(shell PAHOLE=$(PAHOLE) $(srctree)/scripts/pahole-flags.sh)
531 CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
532 -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
541 export LDFLAGS_vmlinux =
543 # Use USERINCLUDE when you must reference the UAPI directories only.
545 -I$(srctree)/arch/$(SRCARCH)/include/uapi \
546 -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
547 -I$(srctree)/include/uapi \
548 -I$(objtree)/include/generated/uapi \
549 -include $(srctree)/include/linux/compiler-version.h \
550 -include $(srctree)/include/linux/kconfig.h
552 # Use LINUXINCLUDE when you must reference the include/ directory.
553 # Needed to be compatible with the O= option
555 -I$(srctree)/arch/$(SRCARCH)/include \
556 -I$(objtree)/arch/$(SRCARCH)/include/generated \
557 $(if $(building_out_of_srctree),-I$(srctree)/include) \
558 -I$(objtree)/include \
561 KBUILD_AFLAGS := -D__ASSEMBLY__ -fno-PIE
562 KBUILD_CFLAGS := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
563 -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
564 -Werror=implicit-function-declaration -Werror=implicit-int \
565 -Werror=return-type -Wno-format-security -funsigned-char \
567 KBUILD_CPPFLAGS := -D__KERNEL__
568 KBUILD_RUSTFLAGS := $(rust_common_flags) \
569 --target=$(objtree)/rust/target.json \
570 -Cpanic=abort -Cembed-bitcode=n -Clto=n \
571 -Cforce-unwind-tables=n -Ccodegen-units=1 \
572 -Csymbol-mangling-version=v0 \
573 -Crelocation-model=static \
574 -Zfunction-sections=n \
575 -Dclippy::float_arithmetic
577 KBUILD_AFLAGS_KERNEL :=
578 KBUILD_CFLAGS_KERNEL :=
579 KBUILD_RUSTFLAGS_KERNEL :=
580 KBUILD_AFLAGS_MODULE := -DMODULE
581 KBUILD_CFLAGS_MODULE := -DMODULE
582 KBUILD_RUSTFLAGS_MODULE := --cfg MODULE
583 KBUILD_LDFLAGS_MODULE :=
587 ifeq ($(KBUILD_CLIPPY),1)
588 RUSTC_OR_CLIPPY_QUIET := CLIPPY
589 RUSTC_OR_CLIPPY = $(CLIPPY_DRIVER)
591 RUSTC_OR_CLIPPY_QUIET := RUSTC
592 RUSTC_OR_CLIPPY = $(RUSTC)
599 # Allows the usage of unstable features in stable compilers.
600 export RUSTC_BOOTSTRAP := 1
602 export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG
603 export RUSTC RUSTDOC RUSTFMT RUSTC_OR_CLIPPY_QUIET RUSTC_OR_CLIPPY BINDGEN CARGO
604 export HOSTRUSTC KBUILD_HOSTRUSTFLAGS
605 export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
606 export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
607 export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
608 export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
609 export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS
611 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
612 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
613 export KBUILD_RUSTFLAGS RUSTFLAGS_KERNEL RUSTFLAGS_MODULE
614 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
615 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_RUSTFLAGS_MODULE KBUILD_LDFLAGS_MODULE
616 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL KBUILD_RUSTFLAGS_KERNEL
619 # Files to ignore in find ... statements
621 export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o \
622 -name CVS -o -name .pc -o -name .hg -o -name .git \) \
624 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
625 --exclude CVS --exclude .pc --exclude .hg --exclude .git
627 # ===========================================================================
628 # Rules shared between *config targets and build targets
630 # Basic helpers built in scripts/basic/
631 PHONY += scripts_basic
633 $(Q)$(MAKE) $(build)=scripts/basic
635 PHONY += outputmakefile
636 ifdef building_out_of_srctree
637 # Before starting out-of-tree build, make sure the source tree is clean.
638 # outputmakefile generates a Makefile in the output directory, if using a
639 # separate output directory. This allows convenient use of make in the
641 # At the same time when output Makefile generated, generate .gitignore to
642 # ignore whole output directory
644 quiet_cmd_makefile = GEN Makefile
646 echo "\# Automatically generated by $(srctree)/Makefile: don't edit"; \
647 echo "include $(srctree)/Makefile"; \
651 @if [ -f $(srctree)/.config -o \
652 -d $(srctree)/include/config -o \
653 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
655 echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
656 echo >&2 "*** in $(abs_srctree)";\
660 $(Q)ln -fsn $(srctree) source
662 $(Q)test -e .gitignore || \
663 { echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
666 # The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
667 # Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
668 # CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
669 # and from include/config/auto.conf.cmd to detect the compiler upgrade.
670 CC_VERSION_TEXT = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1))
672 ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
673 include $(srctree)/scripts/Makefile.clang
676 # Include this also for config targets because some architectures need
677 # cc-cross-prefix to determine CROSS_COMPILE.
679 include $(srctree)/scripts/Makefile.compiler
683 # ===========================================================================
684 # *config targets only - make sure prerequisites are updated, and descend
685 # in scripts/kconfig to make the *config target
687 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
688 # KBUILD_DEFCONFIG may point out an alternative default configuration
689 # used for 'make defconfig'
690 include $(srctree)/arch/$(SRCARCH)/Makefile
691 export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
693 config: outputmakefile scripts_basic FORCE
694 $(Q)$(MAKE) $(build)=scripts/kconfig $@
696 %config: outputmakefile scripts_basic FORCE
697 $(Q)$(MAKE) $(build)=scripts/kconfig $@
700 # ===========================================================================
701 # Build targets only - this includes vmlinux, arch specific targets, clean
702 # targets and others. In general all targets except *config targets.
704 # If building an external module we do not care about the all: rule
705 # but instead __all depend on modules
707 ifeq ($(KBUILD_EXTMOD),)
715 # Decide whether to build built-in, modular, or both.
716 # Normally, just do built-in.
721 # If we have only "make modules", don't compile built-in objects.
722 ifeq ($(MAKECMDGOALS),modules)
726 # If we have "make <whatever> modules", compile modules
727 # in addition to whatever we do anyway.
728 # Just "make" or "make all" shall build modules as well
730 ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
734 ifeq ($(MAKECMDGOALS),)
738 export KBUILD_MODULES KBUILD_BUILTIN
741 include include/config/auto.conf
744 ifeq ($(KBUILD_EXTMOD),)
745 # Objects we will link into vmlinux / subdirs we need to visit
749 endif # KBUILD_EXTMOD
751 # The all: target is the default when no target is given on the
753 # This allow a user to issue only 'make' to build a kernel including modules
754 # Defaults to vmlinux, but the arch makefile usually adds further targets
757 CFLAGS_GCOV := -fprofile-arcs -ftest-coverage
758 ifdef CONFIG_CC_IS_GCC
759 CFLAGS_GCOV += -fno-tree-loop-im
763 # The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
764 ifdef CONFIG_FUNCTION_TRACER
765 CC_FLAGS_FTRACE := -pg
768 include $(srctree)/arch/$(SRCARCH)/Makefile
771 ifdef may-sync-config
772 # Read in dependencies to all Kconfig* files, make sure to run syncconfig if
773 # changes are detected. This should be included after arch/$(SRCARCH)/Makefile
774 # because some architectures define CROSS_COMPILE there.
775 include include/config/auto.conf.cmd
779 @echo >&2 '*** Configuration file "$@" not found!'
781 @echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
782 @echo >&2 '*** "make menuconfig" or "make xconfig").'
786 # The actual configuration files used during the build are stored in
787 # include/generated/ and include/config/. Update them if .config is newer than
788 # include/config/auto.conf (which mirrors .config).
790 # This exploits the 'multi-target pattern rule' trick.
791 # The syncconfig should be executed only once to make all the targets.
792 # (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
794 # Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
795 # so you cannot notice that Kconfig is waiting for the user input.
796 %/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h %/generated/rustc_cfg: $(KCONFIG_CONFIG)
797 $(Q)$(kecho) " SYNC $@"
798 $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
799 else # !may-sync-config
800 # External modules and some install targets need include/generated/autoconf.h
801 # and include/config/auto.conf but do not care if they are up-to-date.
802 # Use auto.conf to trigger the test
803 PHONY += include/config/auto.conf
805 include/config/auto.conf:
806 @test -e include/generated/autoconf.h -a -e $@ || ( \
808 echo >&2 " ERROR: Kernel configuration is invalid."; \
809 echo >&2 " include/generated/autoconf.h or $@ are missing.";\
810 echo >&2 " Run 'make oldconfig && make prepare' on kernel src to fix it."; \
814 endif # may-sync-config
817 KBUILD_CFLAGS += -fno-delete-null-pointer-checks
818 KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,)
819 KBUILD_CFLAGS += $(call cc-disable-warning, format-truncation)
820 KBUILD_CFLAGS += $(call cc-disable-warning, format-overflow)
821 KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
823 ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
825 KBUILD_RUSTFLAGS += -Copt-level=2
826 else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
828 KBUILD_RUSTFLAGS += -Copt-level=s
831 # Always set `debug-assertions` and `overflow-checks` because their default
832 # depends on `opt-level` and `debug-assertions`, respectively.
833 KBUILD_RUSTFLAGS += -Cdebug-assertions=$(if $(CONFIG_RUST_DEBUG_ASSERTIONS),y,n)
834 KBUILD_RUSTFLAGS += -Coverflow-checks=$(if $(CONFIG_RUST_OVERFLOW_CHECKS),y,n)
836 # Tell gcc to never replace conditional load with a non-conditional one
837 ifdef CONFIG_CC_IS_GCC
838 # gcc-10 renamed --param=allow-store-data-races=0 to
839 # -fno-allow-store-data-races.
840 KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
841 KBUILD_CFLAGS += $(call cc-option,-fno-allow-store-data-races)
844 ifdef CONFIG_READABLE_ASM
845 # Disable optimizations that make assembler listings hard to read.
846 # reorder blocks reorders the control in the function
847 # ipa clone creates specialized cloned functions
848 # partial inlining inlines only parts of functions
849 KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
852 ifneq ($(CONFIG_FRAME_WARN),0)
853 KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
856 stackp-flags-y := -fno-stack-protector
857 stackp-flags-$(CONFIG_STACKPROTECTOR) := -fstack-protector
858 stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG) := -fstack-protector-strong
860 KBUILD_CFLAGS += $(stackp-flags-y)
862 KBUILD_CFLAGS-$(CONFIG_WERROR) += -Werror
863 KBUILD_CFLAGS-$(CONFIG_CC_NO_ARRAY_BOUNDS) += -Wno-array-bounds
865 KBUILD_RUSTFLAGS-$(CONFIG_WERROR) += -Dwarnings
866 KBUILD_RUSTFLAGS += $(KBUILD_RUSTFLAGS-y)
868 ifdef CONFIG_CC_IS_CLANG
869 KBUILD_CPPFLAGS += -Qunused-arguments
870 # The kernel builds with '-std=gnu11' so use of GNU extensions is acceptable.
871 KBUILD_CFLAGS += -Wno-gnu
874 # gcc inanely warns about local variables called 'main'
875 KBUILD_CFLAGS += -Wno-main
878 # These warnings generated too much noise in a regular build.
879 # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
880 KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
881 KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
883 # These result in bogus false positives
884 KBUILD_CFLAGS += $(call cc-disable-warning, dangling-pointer)
886 ifdef CONFIG_FRAME_POINTER
887 KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
888 KBUILD_RUSTFLAGS += -Cforce-frame-pointers=y
890 # Some targets (ARM with Thumb2, for example), can't be built with frame
891 # pointers. For those, we don't have FUNCTION_TRACER automatically
892 # select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
893 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
894 # -fomit-frame-pointer with FUNCTION_TRACER.
895 # In the Rust target specification, "frame-pointer" is set explicitly
897 ifndef CONFIG_FUNCTION_TRACER
898 KBUILD_CFLAGS += -fomit-frame-pointer
902 # Initialize all stack variables with a 0xAA pattern.
903 ifdef CONFIG_INIT_STACK_ALL_PATTERN
904 KBUILD_CFLAGS += -ftrivial-auto-var-init=pattern
907 # Initialize all stack variables with a zero value.
908 ifdef CONFIG_INIT_STACK_ALL_ZERO
909 KBUILD_CFLAGS += -ftrivial-auto-var-init=zero
910 ifdef CONFIG_CC_HAS_AUTO_VAR_INIT_ZERO_ENABLER
911 # https://github.com/llvm/llvm-project/issues/44842
912 KBUILD_CFLAGS += -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
916 # While VLAs have been removed, GCC produces unreachable stack probes
917 # for the randomize_kstack_offset feature. Disable it for all compilers.
918 KBUILD_CFLAGS += $(call cc-option, -fno-stack-clash-protection)
920 # Clear used registers at func exit (to reduce data lifetime and ROP gadgets).
921 ifdef CONFIG_ZERO_CALL_USED_REGS
922 KBUILD_CFLAGS += -fzero-call-used-regs=used-gpr
925 ifdef CONFIG_FUNCTION_TRACER
926 ifdef CONFIG_FTRACE_MCOUNT_USE_CC
927 CC_FLAGS_FTRACE += -mrecord-mcount
928 ifdef CONFIG_HAVE_NOP_MCOUNT
929 ifeq ($(call cc-option-yn, -mnop-mcount),y)
930 CC_FLAGS_FTRACE += -mnop-mcount
931 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
935 ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
936 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
938 ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
939 ifdef CONFIG_HAVE_C_RECORDMCOUNT
940 BUILD_C_RECORDMCOUNT := y
941 export BUILD_C_RECORDMCOUNT
944 ifdef CONFIG_HAVE_FENTRY
945 # s390-linux-gnu-gcc did not support -mfentry until gcc-9.
946 ifeq ($(call cc-option-yn, -mfentry),y)
947 CC_FLAGS_FTRACE += -mfentry
948 CC_FLAGS_USING += -DCC_USING_FENTRY
951 export CC_FLAGS_FTRACE
952 KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
953 KBUILD_AFLAGS += $(CC_FLAGS_USING)
956 # We trigger additional mismatches with less inlining
957 ifdef CONFIG_DEBUG_SECTION_MISMATCH
958 KBUILD_CFLAGS += -fno-inline-functions-called-once
961 # `rustc`'s `-Zfunction-sections` applies to data too (as of 1.59.0).
962 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
963 KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
964 KBUILD_RUSTFLAGS_KERNEL += -Zfunction-sections=y
965 LDFLAGS_vmlinux += --gc-sections
968 ifdef CONFIG_SHADOW_CALL_STACK
969 ifndef CONFIG_DYNAMIC_SCS
970 CC_FLAGS_SCS := -fsanitize=shadow-call-stack
971 KBUILD_CFLAGS += $(CC_FLAGS_SCS)
976 ifdef CONFIG_LTO_CLANG
977 ifdef CONFIG_LTO_CLANG_THIN
978 CC_FLAGS_LTO := -flto=thin -fsplit-lto-unit
979 KBUILD_LDFLAGS += --thinlto-cache-dir=$(extmod_prefix).thinlto-cache
981 CC_FLAGS_LTO := -flto
983 CC_FLAGS_LTO += -fvisibility=hidden
985 # Limit inlining across translation units to reduce binary size
986 KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
988 # Check for frame size exceeding threshold during prolog/epilog insertion
989 # when using lld < 13.0.0.
990 ifneq ($(CONFIG_FRAME_WARN),0)
991 ifeq ($(shell test $(CONFIG_LLD_VERSION) -lt 130000; echo $$?),0)
992 KBUILD_LDFLAGS += -plugin-opt=-warn-stack-size=$(CONFIG_FRAME_WARN)
998 KBUILD_CFLAGS += -fno-lto $(CC_FLAGS_LTO)
999 KBUILD_AFLAGS += -fno-lto
1003 ifdef CONFIG_CFI_CLANG
1004 CC_FLAGS_CFI := -fsanitize=kcfi
1005 KBUILD_CFLAGS += $(CC_FLAGS_CFI)
1009 ifneq ($(CONFIG_FUNCTION_ALIGNMENT),0)
1010 KBUILD_CFLAGS += -falign-functions=$(CONFIG_FUNCTION_ALIGNMENT)
1013 # arch Makefile may override CC so keep this after arch Makefile is included
1014 NOSTDINC_FLAGS += -nostdinc
1016 # warn about C99 declaration after statement
1017 KBUILD_CFLAGS += -Wdeclaration-after-statement
1019 # Variable Length Arrays (VLAs) should not be used anywhere in the kernel
1020 KBUILD_CFLAGS += -Wvla
1022 # disable pointer signed / unsigned warnings in gcc 4.0
1023 KBUILD_CFLAGS += -Wno-pointer-sign
1025 # In order to make sure new function cast mismatches are not introduced
1026 # in the kernel (to avoid tripping CFI checking), the kernel should be
1027 # globally built with -Wcast-function-type.
1028 KBUILD_CFLAGS += $(call cc-option, -Wcast-function-type)
1030 # disable stringop warnings in gcc 8+
1031 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
1033 # We'll want to enable this eventually, but it's not going away for 5.7 at least
1034 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
1036 # Another good warning that we'll want to enable eventually
1037 KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
1039 # Enabled with W=2, disabled by default as noisy
1040 ifdef CONFIG_CC_IS_GCC
1041 KBUILD_CFLAGS += -Wno-maybe-uninitialized
1044 # The allocators already balk at large sizes, so silence the compiler
1045 # warnings for bounds checks involving those possible values. While
1046 # -Wno-alloc-size-larger-than would normally be used here, earlier versions
1047 # of gcc (<9.1) weirdly don't handle the option correctly when _other_
1048 # warnings are produced (?!). Using -Walloc-size-larger-than=SIZE_MAX
1049 # doesn't work (as it is documented to), silently resolving to "0" prior to
1050 # version 9.1 (and producing an error more recently). Numeric values larger
1051 # than PTRDIFF_MAX also don't work prior to version 9.1, which are silently
1052 # ignored, continuing to default to PTRDIFF_MAX. So, left with no other
1053 # choice, we must perform a versioned check to disable this warning.
1054 # https://lore.kernel.org/lkml/20210824115859.187f272f@canb.auug.org.au
1055 KBUILD_CFLAGS-$(call gcc-min-version, 90100) += -Wno-alloc-size-larger-than
1056 KBUILD_CFLAGS += $(KBUILD_CFLAGS-y) $(CONFIG_CC_IMPLICIT_FALLTHROUGH)
1058 # disable invalid "can't wrap" optimizations for signed / pointers
1059 KBUILD_CFLAGS += -fno-strict-overflow
1061 # Make sure -fstack-check isn't enabled (like gentoo apparently did)
1062 KBUILD_CFLAGS += -fno-stack-check
1064 # conserve stack if available
1065 ifdef CONFIG_CC_IS_GCC
1066 KBUILD_CFLAGS += -fconserve-stack
1069 # Prohibit date/time macros, which would make the build non-deterministic
1070 KBUILD_CFLAGS += -Werror=date-time
1072 # enforce correct pointer usage
1073 KBUILD_CFLAGS += $(call cc-option,-Werror=incompatible-pointer-types)
1075 # Require designated initializers for all marked structures
1076 KBUILD_CFLAGS += $(call cc-option,-Werror=designated-init)
1078 # change __FILE__ to the relative path from the srctree
1079 KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
1081 # include additional Makefiles when needed
1082 include-y := scripts/Makefile.extrawarn
1083 include-$(CONFIG_DEBUG_INFO) += scripts/Makefile.debug
1084 include-$(CONFIG_KASAN) += scripts/Makefile.kasan
1085 include-$(CONFIG_KCSAN) += scripts/Makefile.kcsan
1086 include-$(CONFIG_KMSAN) += scripts/Makefile.kmsan
1087 include-$(CONFIG_UBSAN) += scripts/Makefile.ubsan
1088 include-$(CONFIG_KCOV) += scripts/Makefile.kcov
1089 include-$(CONFIG_RANDSTRUCT) += scripts/Makefile.randstruct
1090 include-$(CONFIG_GCC_PLUGINS) += scripts/Makefile.gcc-plugins
1092 include $(addprefix $(srctree)/, $(include-y))
1094 # scripts/Makefile.gcc-plugins is intentionally included last.
1095 # Do not add $(call cc-option,...) below this line. When you build the kernel
1096 # from the clean source tree, the GCC plugins do not exist at this point.
1098 # Add user supplied CPPFLAGS, AFLAGS, CFLAGS and RUSTFLAGS as the last assignments
1099 KBUILD_CPPFLAGS += $(KCPPFLAGS)
1100 KBUILD_AFLAGS += $(KAFLAGS)
1101 KBUILD_CFLAGS += $(KCFLAGS)
1102 KBUILD_RUSTFLAGS += $(KRUSTFLAGS)
1104 KBUILD_LDFLAGS_MODULE += --build-id=sha1
1105 LDFLAGS_vmlinux += --build-id=sha1
1107 KBUILD_LDFLAGS += -z noexecstack
1108 ifeq ($(CONFIG_LD_IS_BFD),y)
1109 KBUILD_LDFLAGS += $(call ld-option,--no-warn-rwx-segments)
1112 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1113 LDFLAGS_vmlinux += -X
1116 ifeq ($(CONFIG_RELR),y)
1117 LDFLAGS_vmlinux += --pack-dyn-relocs=relr --use-android-relr-tags
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) $@ $$($(AR) t $@ | grep -F -f $(srctree)/scripts/head-object-list.txt)
1225 targets += vmlinux.a
1226 vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt autoksyms_recursive FORCE
1227 $(call if_changed,ar_vmlinux.a)
1230 vmlinux_o: vmlinux.a $(KBUILD_VMLINUX_LIBS)
1231 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o
1233 vmlinux.o modules.builtin.modinfo modules.builtin: vmlinux_o
1237 vmlinux: vmlinux.o $(KBUILD_LDS) modpost
1238 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux
1240 # The actual objects are generated when descending,
1241 # make sure no implicit rule kicks in
1242 $(sort $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)): . ;
1244 filechk_kernel.release = \
1245 echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1247 # Store (new) KERNELRELEASE string in include/config/kernel.release
1248 include/config/kernel.release: FORCE
1249 $(call filechk,kernel.release)
1251 # Additional helpers built in scripts/
1252 # Carefully list dependencies so we do not try to build scripts twice
1255 scripts: scripts_basic scripts_dtc
1256 $(Q)$(MAKE) $(build)=$(@)
1258 # Things we need to do before we recursively start building the kernel
1259 # or the modules are listed in "prepare".
1260 # A multi level approach is used. prepareN is processed before prepareN-1.
1261 # archprepare is used in arch Makefiles and when processed asm symlink,
1262 # version.h and scripts_basic is processed / created.
1264 PHONY += prepare archprepare
1266 archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1267 asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h \
1268 include/generated/compile.h include/generated/autoconf.h remove-stale-files
1270 prepare0: archprepare
1271 $(Q)$(MAKE) $(build)=scripts/mod
1272 $(Q)$(MAKE) $(build)=. prepare
1274 # All the preparing..
1277 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh -v
1278 $(Q)$(MAKE) $(build)=rust
1281 PHONY += remove-stale-files
1283 $(Q)$(srctree)/scripts/remove-stale-files
1285 # Support for using generic headers in asm-generic
1286 asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1288 PHONY += asm-generic uapi-asm-generic
1289 asm-generic: uapi-asm-generic
1290 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1291 generic=include/asm-generic
1293 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1294 generic=include/uapi/asm-generic
1296 # Generate some files
1297 # ---------------------------------------------------------------------------
1299 # KERNELRELEASE can change from a few different places, meaning version.h
1300 # needs to be updated, so this check is forced on all builds
1303 define filechk_utsrelease.h
1304 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1305 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1308 echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1311 define filechk_version.h
1312 if [ $(SUBLEVEL) -gt 255 ]; then \
1313 echo \#define LINUX_VERSION_CODE $(shell \
1314 expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1316 echo \#define LINUX_VERSION_CODE $(shell \
1317 expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1319 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + \
1320 ((c) > 255 ? 255 : (c)))'; \
1321 echo \#define LINUX_VERSION_MAJOR $(VERSION); \
1322 echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL); \
1323 echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1326 $(version_h): PATCHLEVEL := $(or $(PATCHLEVEL), 0)
1327 $(version_h): SUBLEVEL := $(or $(SUBLEVEL), 0)
1329 $(call filechk,version.h)
1331 include/generated/utsrelease.h: include/config/kernel.release FORCE
1332 $(call filechk,utsrelease.h)
1334 filechk_compile.h = $(srctree)/scripts/mkcompile_h \
1335 "$(UTS_MACHINE)" "$(CONFIG_CC_VERSION_TEXT)" "$(LD)"
1337 include/generated/compile.h: FORCE
1338 $(call filechk,compile.h)
1342 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1343 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1345 # ---------------------------------------------------------------------------
1348 #Default location for installed headers
1349 export INSTALL_HDR_PATH = $(objtree)/usr
1351 quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1352 cmd_headers_install = \
1353 mkdir -p $(INSTALL_HDR_PATH); \
1354 rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1355 usr/include $(INSTALL_HDR_PATH)
1357 PHONY += headers_install
1358 headers_install: headers
1359 $(call cmd,headers_install)
1361 PHONY += archheaders archscripts
1363 hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1366 headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1367 $(if $(filter um, $(SRCARCH)), $(error Headers not exportable for UML))
1368 $(Q)$(MAKE) $(hdr-inst)=include/uapi
1369 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1371 ifdef CONFIG_HEADERS_INSTALL
1375 PHONY += scripts_unifdef
1376 scripts_unifdef: scripts_basic
1377 $(Q)$(MAKE) $(build)=scripts scripts/unifdef
1379 # ---------------------------------------------------------------------------
1382 # Many distributions have the custom install script, /sbin/installkernel.
1383 # If DKMS is installed, 'make install' will eventually recurse back
1384 # to this Makefile to build and install external modules.
1385 # Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
1387 quiet_cmd_install = INSTALL $(INSTALL_PATH)
1388 cmd_install = unset sub_make_done; $(srctree)/scripts/install.sh
1390 # ---------------------------------------------------------------------------
1393 ifdef CONFIG_OBJTOOL
1394 prepare: tools/objtool
1398 ifdef CONFIG_DEBUG_INFO_BTF
1399 prepare: tools/bpf/resolve_btfids
1403 PHONY += resolve_btfids_clean
1405 resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1407 # tools/bpf/resolve_btfids directory might not exist
1408 # in output directory, skip its clean in that case
1409 resolve_btfids_clean:
1410 ifneq ($(wildcard $(resolve_btfids_O)),)
1411 $(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1414 # Clear a bunch of variables before executing the submake
1415 ifeq ($(quiet),silent_)
1420 $(Q)mkdir -p $(objtree)/tools
1421 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1424 $(Q)mkdir -p $(objtree)/tools
1425 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1427 # ---------------------------------------------------------------------------
1432 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1434 kselftest-%: headers FORCE
1435 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1437 PHONY += kselftest-merge
1439 $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1440 $(Q)find $(srctree)/tools/testing/selftests -name config | \
1441 xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1442 $(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1444 # ---------------------------------------------------------------------------
1447 ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1448 dtstree := arch/$(SRCARCH)/boot/dts
1454 $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1456 %.dtbo: dtbs_prepare
1457 $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1459 PHONY += dtbs dtbs_prepare dtbs_install dtbs_check
1461 $(Q)$(MAKE) $(build)=$(dtstree)
1463 # include/config/kernel.release is actually needed when installing DTBs because
1464 # INSTALL_DTBS_PATH contains $(KERNELRELEASE). However, we do not want to make
1465 # dtbs_install depend on it as dtbs_install may run as root.
1466 dtbs_prepare: include/config/kernel.release scripts_dtc
1468 ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1470 dtbs: dt_binding_check
1476 $(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1478 ifdef CONFIG_OF_EARLY_FLATTREE
1484 PHONY += scripts_dtc
1485 scripts_dtc: scripts_basic
1486 $(Q)$(MAKE) $(build)=scripts/dtc
1488 ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1489 export CHECK_DT_BINDING=y
1492 PHONY += dt_binding_check
1493 dt_binding_check: scripts_dtc
1494 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1496 PHONY += dt_compatible_check
1497 dt_compatible_check: dt_binding_check
1498 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1500 # ---------------------------------------------------------------------------
1503 ifdef CONFIG_MODULES
1505 # By default, build modules as well
1509 # When we're building modules with modversions, we need to consider
1510 # the built-in objects during the descend as well, in order to
1511 # make sure the checksums are up to date before we record them.
1512 ifdef CONFIG_MODVERSIONS
1519 # *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFOBTF_MODULES
1521 ifdef CONFIG_DEBUG_INFO_BTF_MODULES
1525 modules: modules_prepare
1527 # Target to prepare building external modules
1528 modules_prepare: prepare
1529 $(Q)$(MAKE) $(build)=scripts scripts/module.lds
1531 export modules_sign_only :=
1533 ifeq ($(CONFIG_MODULE_SIG),y)
1534 PHONY += modules_sign
1535 modules_sign: modules_install
1538 # modules_sign is a subset of modules_install.
1539 # 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1540 ifeq ($(filter modules_install,$(MAKECMDGOALS)),)
1541 modules_sign_only := y
1546 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
1547 modinst_pre := __modinst_pre
1550 modules_install: $(modinst_pre)
1551 PHONY += __modinst_pre
1553 @rm -rf $(MODLIB)/kernel
1554 @rm -f $(MODLIB)/source
1555 @mkdir -p $(MODLIB)/kernel
1556 @ln -s $(abspath $(srctree)) $(MODLIB)/source
1557 @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
1558 rm -f $(MODLIB)/build ; \
1559 ln -s $(CURDIR) $(MODLIB)/build ; \
1561 @sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order
1562 @cp -f modules.builtin $(MODLIB)/
1563 @cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
1565 endif # CONFIG_MODULES
1568 # Cleaning is done on three levels.
1569 # make clean Delete most generated files
1570 # Leave enough to build external modules
1571 # make mrproper Delete the current configuration, and all generated files
1572 # make distclean Remove editor backup files, patch leftover files and the like
1574 # Directories & files removed with 'make clean'
1575 CLEAN_FILES += include/ksym vmlinux.symvers modules-only.symvers \
1576 modules.builtin modules.builtin.modinfo modules.nsdeps \
1577 compile_commands.json .thinlto-cache rust/test rust/doc \
1578 .vmlinux.objs .vmlinux.export.c
1580 # Directories & files removed with 'make mrproper'
1581 MRPROPER_FILES += include/config include/generated \
1582 arch/$(SRCARCH)/include/generated .objdiff \
1583 debian snap tar-install \
1584 .config .config.old .version \
1586 certs/signing_key.pem \
1590 rust/target.json rust/libmacros.so
1592 # clean - Delete most, but leave enough to build external modules
1594 clean: rm-files := $(CLEAN_FILES)
1596 PHONY += archclean vmlinuxclean
1599 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1600 $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1602 clean: archclean vmlinuxclean resolve_btfids_clean
1604 # mrproper - Delete all generated files, including .config
1606 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1607 mrproper-dirs := $(addprefix _mrproper_,scripts)
1609 PHONY += $(mrproper-dirs) mrproper
1611 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1613 mrproper: clean $(mrproper-dirs)
1615 @find . $(RCS_FIND_IGNORE) \
1616 \( -name '*.rmeta' \) \
1617 -type f -print | xargs rm -f
1624 @find . $(RCS_FIND_IGNORE) \
1625 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1626 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1627 -o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1628 -o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1629 -type f -print | xargs rm -f
1632 # Packaging of the kernel to various formats
1633 # ---------------------------------------------------------------------------
1636 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1637 %pkg: include/config/kernel.release FORCE
1638 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1640 # Brief documentation of the typical targets used
1641 # ---------------------------------------------------------------------------
1643 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1644 boards := $(sort $(notdir $(boards)))
1645 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1646 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1650 @echo 'Cleaning targets:'
1651 @echo ' clean - Remove most generated files but keep the config and'
1652 @echo ' enough build support to build external modules'
1653 @echo ' mrproper - Remove all generated files + config + various backup files'
1654 @echo ' distclean - mrproper + remove editor backup and patch files'
1656 @echo 'Configuration targets:'
1657 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1659 @echo 'Other generic targets:'
1660 @echo ' all - Build all targets marked with [*]'
1661 @echo '* vmlinux - Build the bare kernel'
1662 @echo '* modules - Build all modules'
1663 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1664 @echo ' dir/ - Build all files in dir and below'
1665 @echo ' dir/file.[ois] - Build specified target only'
1666 @echo ' dir/file.ll - Build the LLVM assembly file'
1667 @echo ' (requires compiler support for LLVM assembly generation)'
1668 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1669 @echo ' (requires a recent binutils and recent build (System.map))'
1670 @echo ' dir/file.ko - Build module including final link'
1671 @echo ' modules_prepare - Set up for building external modules'
1672 @echo ' tags/TAGS - Generate tags file for editors'
1673 @echo ' cscope - Generate cscope index'
1674 @echo ' gtags - Generate GNU GLOBAL index'
1675 @echo ' kernelrelease - Output the release version string (use with make -s)'
1676 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1677 @echo ' image_name - Output the image name (use with make -s)'
1678 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1679 echo ' (default: $(INSTALL_HDR_PATH))'; \
1681 @echo 'Static analysers:'
1682 @echo ' checkstack - Generate a list of stack hogs'
1683 @echo ' versioncheck - Sanity check on version.h usage'
1684 @echo ' includecheck - Check for duplicate included header files'
1685 @echo ' export_report - List the usages of all exported symbols'
1686 @echo ' headerdep - Detect inclusion cycles in headers'
1687 @echo ' coccicheck - Check with Coccinelle'
1688 @echo ' clang-analyzer - Check with clang static analyzer'
1689 @echo ' clang-tidy - Check with clang-tidy'
1692 @echo ' nsdeps - Generate missing symbol namespace dependencies'
1694 @echo 'Kernel selftest:'
1695 @echo ' kselftest - Build and run kernel selftest'
1696 @echo ' Build, install, and boot kernel before'
1697 @echo ' running kselftest on it'
1698 @echo ' Run as root for full coverage'
1699 @echo ' kselftest-all - Build kernel selftest'
1700 @echo ' kselftest-install - Build and install kernel selftest'
1701 @echo ' kselftest-clean - Remove all generated kselftest files'
1702 @echo ' kselftest-merge - Merge all the config dependencies of'
1703 @echo ' kselftest to existing .config.'
1705 @echo 'Rust targets:'
1706 @echo ' rustavailable - Checks whether the Rust toolchain is'
1707 @echo ' available and, if not, explains why.'
1708 @echo ' rustfmt - Reformat all the Rust code in the kernel'
1709 @echo ' rustfmtcheck - Checks if all the Rust code in the kernel'
1710 @echo ' is formatted, printing a diff otherwise.'
1711 @echo ' rustdoc - Generate Rust documentation'
1712 @echo ' (requires kernel .config)'
1713 @echo ' rusttest - Runs the Rust tests'
1714 @echo ' (requires kernel .config; downloads external repos)'
1715 @echo ' rust-analyzer - Generate rust-project.json rust-analyzer support file'
1716 @echo ' (requires kernel .config)'
1717 @echo ' dir/file.[os] - Build specified target only'
1718 @echo ' dir/file.rsi - Build macro expanded source, similar to C preprocessing.'
1719 @echo ' Run with RUSTFMT=n to skip reformatting if needed.'
1720 @echo ' The output is not intended to be compilable.'
1721 @echo ' dir/file.ll - Build the LLVM assembly file'
1724 echo 'Devicetree:'; \
1725 echo '* dtbs - Build device tree blobs for enabled boards'; \
1726 echo ' dtbs_install - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1727 echo ' dt_binding_check - Validate device tree binding documents'; \
1728 echo ' dtbs_check - Validate device tree source files';\
1731 @echo 'Userspace tools targets:'
1732 @echo ' use "make tools/help"'
1733 @echo ' or "cd tools; make help"'
1735 @echo 'Kernel packaging:'
1736 @$(MAKE) -f $(srctree)/scripts/Makefile.package help
1738 @echo 'Documentation targets:'
1739 @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1741 @echo 'Architecture specific targets ($(SRCARCH)):'
1743 echo ' No architecture specific help defined for $(SRCARCH)')
1746 $(foreach b, $(boards), \
1747 printf " %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1749 @$(if $(board-dirs), \
1750 $(foreach b, $(board-dirs), \
1751 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1752 printf " %-16s - Show all of the above\\n" help-boards; \
1755 @echo ' make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1756 @echo ' make V=2 [targets] 2 => give reason for rebuild of target'
1757 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1758 @echo ' make C=1 [targets] Check re-compiled c source with $$CHECK'
1759 @echo ' (sparse by default)'
1760 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1761 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1762 @echo ' make W=n [targets] Enable extra build checks, n=1,2,3 where'
1763 @echo ' 1: warnings which may be relevant and do not occur too often'
1764 @echo ' 2: warnings which occur quite often but may still be relevant'
1765 @echo ' 3: more obscure warnings, can most likely be ignored'
1766 @echo ' e: warnings are being treated as errors'
1767 @echo ' Multiple levels can be combined with W=12 or W=123'
1769 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1770 @echo 'For further info see the ./README file'
1773 help-board-dirs := $(addprefix help-,$(board-dirs))
1775 help-boards: $(help-board-dirs)
1777 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1779 $(help-board-dirs): help-%:
1780 @echo 'Architecture specific targets ($(SRCARCH) $*):'
1781 @$(if $(boards-per-dir), \
1782 $(foreach b, $(boards-per-dir), \
1783 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1787 # Documentation targets
1788 # ---------------------------------------------------------------------------
1789 DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1790 linkcheckdocs dochelp refcheckdocs texinfodocs infodocs
1791 PHONY += $(DOC_TARGETS)
1793 $(Q)$(MAKE) $(build)=Documentation $@
1797 # ---------------------------------------------------------------------------
1799 # "Is Rust available?" target
1800 PHONY += rustavailable
1802 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh -v && echo "Rust is available!"
1804 # Documentation target
1806 # Using the singular to avoid running afoul of `no-dot-config-targets`.
1809 $(Q)$(MAKE) $(build)=rust $@
1814 $(Q)$(MAKE) $(build)=rust $@
1816 # Formatting targets
1817 PHONY += rustfmt rustfmtcheck
1819 # We skip `rust/alloc` since we want to minimize the diff w.r.t. upstream.
1821 # We match using absolute paths since `find` does not resolve them
1822 # when matching, which is a problem when e.g. `srctree` is `..`.
1823 # We `grep` afterwards in order to remove the directory entry itself.
1825 $(Q)find $(abs_srctree) -type f -name '*.rs' \
1826 -o -path $(abs_srctree)/rust/alloc -prune \
1827 -o -path $(abs_objtree)/rust/test -prune \
1828 | grep -Fv $(abs_srctree)/rust/alloc \
1829 | grep -Fv $(abs_objtree)/rust/test \
1830 | grep -Fv generated \
1831 | xargs $(RUSTFMT) $(rustfmt_flags)
1833 rustfmtcheck: rustfmt_flags = --check
1834 rustfmtcheck: rustfmt
1836 # IDE support targets
1837 PHONY += rust-analyzer
1839 $(Q)$(MAKE) $(build)=rust $@
1842 # ---------------------------------------------------------------------------
1844 PHONY += scripts_gdb
1845 scripts_gdb: prepare0
1846 $(Q)$(MAKE) $(build)=scripts/gdb
1847 $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1849 ifdef CONFIG_GDB_SCRIPTS
1853 else # KBUILD_EXTMOD
1856 # External module support.
1857 # When building external modules the kernel used as basis is considered
1858 # read-only, and no consistency checks are made and the make
1859 # system is not used on the basis kernel. If updates are required
1860 # in the basis kernel ordinary make commands (without M=...) must be used.
1862 # We are always building only modules.
1866 build-dir := $(KBUILD_EXTMOD)
1868 compile_commands.json: $(extmod_prefix)compile_commands.json
1869 PHONY += compile_commands.json
1871 clean-dirs := $(KBUILD_EXTMOD)
1872 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1873 $(KBUILD_EXTMOD)/compile_commands.json $(KBUILD_EXTMOD)/.thinlto-cache
1876 # now expand this into a simple variable to reduce the cost of shell evaluations
1877 prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT)
1879 @if [ "$(CC_VERSION_TEXT)" != "$(CONFIG_CC_VERSION_TEXT)" ]; then \
1880 echo >&2 "warning: the compiler differs from the one used to build the kernel"; \
1881 echo >&2 " The kernel was built by: $(CONFIG_CC_VERSION_TEXT)"; \
1882 echo >&2 " You are using: $(CC_VERSION_TEXT)"; \
1887 @echo ' Building external modules.'
1888 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1890 @echo ' modules - default target, build the module(s)'
1891 @echo ' modules_install - install the module'
1892 @echo ' clean - remove generated files in module directory only'
1895 endif # KBUILD_EXTMOD
1897 # ---------------------------------------------------------------------------
1900 PHONY += modules modules_install modules_prepare
1902 ifdef CONFIG_MODULES
1904 $(MODORDER): $(build-dir)
1907 # KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
1908 # This is solely useful to speed up test compiles.
1910 ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1911 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1914 PHONY += modules_check
1915 modules_check: $(MODORDER)
1916 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1918 quiet_cmd_depmod = DEPMOD $(MODLIB)
1919 cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1923 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1926 else # CONFIG_MODULES
1928 # Modules not configured
1929 # ---------------------------------------------------------------------------
1931 modules modules_install:
1933 @echo >&2 '*** The present kernel configuration has modules disabled.'
1934 @echo >&2 '*** To use the module feature, please run "make menuconfig" etc.'
1935 @echo >&2 '*** to enable CONFIG_MODULES.'
1941 endif # CONFIG_MODULES
1944 modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \
1945 $(if $(KBUILD_MODULES), modules_check)
1946 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1949 # ---------------------------------------------------------------------------
1950 # To build individual files in subdirectories, you can do like this:
1952 # make foo/bar/baz.s
1954 # The supported suffixes for single-target are listed in 'single-targets'
1956 # To build only under specific subdirectories, you can do like this:
1962 # .ko is special because modpost is needed
1963 single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1964 single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \
1965 $(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko)))
1967 $(single-ko): single_modules
1969 $(single-no-ko): $(build-dir)
1972 # Remove MODORDER when done because it is not the real one.
1973 PHONY += single_modules
1974 single_modules: $(single-no-ko) modules_prepare
1975 $(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$m;) } > $(MODORDER)
1976 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1977 ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1978 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1980 $(Q)rm -f $(MODORDER)
1982 single-goals := $(addprefix $(build-dir)/, $(single-no-ko))
1988 # Preset locale variables to speed up the build process. Limit locale
1989 # tweaks to this spot to avoid wrong language settings when running
1990 # make menuconfig etc.
1991 # Error messages still appears in the original language
1992 PHONY += $(build-dir)
1993 $(build-dir): prepare
1994 $(Q)$(MAKE) $(build)=$@ need-builtin=1 need-modorder=1 $(single-goals)
1996 clean-dirs := $(addprefix _clean_, $(clean-dirs))
1997 PHONY += $(clean-dirs) clean
1999 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
2001 clean: $(clean-dirs)
2003 @find $(or $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
2004 \( -name '*.[aios]' -o -name '*.rsi' -o -name '*.ko' -o -name '.*.cmd' \
2006 -o -name '*.dtb' -o -name '*.dtbo' \
2007 -o -name '*.dtb.S' -o -name '*.dtbo.S' \
2008 -o -name '*.dt.yaml' \
2009 -o -name '*.dwo' -o -name '*.lst' \
2010 -o -name '*.su' -o -name '*.mod' -o -name '*.usyms' \
2011 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
2012 -o -name '*.lex.c' -o -name '*.tab.[ch]' \
2013 -o -name '*.asn1.[ch]' \
2014 -o -name '*.symtypes' -o -name 'modules.order' \
2016 -o -name '*.c.[012]*.*' \
2019 -o -name '*.*.symversions' \) -type f -print | xargs rm -f
2021 # Generate tags for editors
2022 # ---------------------------------------------------------------------------
2023 quiet_cmd_tags = GEN $@
2024 cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
2026 tags TAGS cscope gtags: FORCE
2029 # Script to generate missing namespace dependencies
2030 # ---------------------------------------------------------------------------
2033 nsdeps: export KBUILD_NSDEPS=1
2035 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
2038 # ---------------------------------------------------------------------------
2040 quiet_cmd_gen_compile_commands = GEN $@
2041 cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
2043 $(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
2044 $(if $(KBUILD_EXTMOD),, vmlinux.a $(KBUILD_VMLINUX_LIBS)) \
2045 $(if $(CONFIG_MODULES), $(MODORDER)) FORCE
2046 $(call if_changed,gen_compile_commands)
2048 targets += $(extmod_prefix)compile_commands.json
2050 PHONY += clang-tidy clang-analyzer
2052 ifdef CONFIG_CC_IS_CLANG
2053 quiet_cmd_clang_tools = CHECK $<
2054 cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
2056 clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
2057 $(call cmd,clang_tools)
2059 clang-tidy clang-analyzer:
2060 @echo "$@ requires CC=clang" >&2
2064 # Scripts to check various things for consistency
2065 # ---------------------------------------------------------------------------
2067 PHONY += includecheck versioncheck coccicheck export_report
2070 find $(srctree)/* $(RCS_FIND_IGNORE) \
2071 -name '*.[hcS]' -type f -print | sort \
2072 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
2075 find $(srctree)/* $(RCS_FIND_IGNORE) \
2076 -name '*.[hcS]' -type f -print | sort \
2077 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
2080 $(Q)$(BASH) $(srctree)/scripts/$@
2083 $(PERL) $(srctree)/scripts/export_report.pl
2085 PHONY += checkstack kernelrelease kernelversion image_name
2087 # UML needs a little special treatment here. It wants to use the host
2088 # toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
2089 # else wants $(ARCH), including people doing cross-builds, which means
2090 # that $(SUBARCH) doesn't work here.
2092 CHECKSTACK_ARCH := $(SUBARCH)
2094 CHECKSTACK_ARCH := $(ARCH)
2097 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
2098 $(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
2101 @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
2104 @echo $(KERNELVERSION)
2107 @echo $(KBUILD_IMAGE)
2109 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
2110 cmd_rmfiles = rm -rf $(rm-files)
2112 # read saved command lines for existing targets
2113 existing-targets := $(wildcard $(sort $(targets)))
2115 -include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
2117 endif # config-build
2119 endif # need-sub-make
2124 # Declare the contents of the PHONY variable as phony. We keep that
2125 # information in a variable so we can use it in if_changed and friends.