1 # SPDX-License-Identifier: GPL-2.0
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 ($(KBUILD_VERBOSE),1)
94 # If the user is running make -s (silent mode), suppress echoing of
96 # make-4.0 (and later) keep single letter options in the 1st word of MAKEFLAGS.
98 ifeq ($(filter 3.%,$(MAKE_VERSION)),)
99 silence:=$(findstring s,$(firstword -$(MAKEFLAGS)))
101 silence:=$(findstring s,$(filter-out --%,$(MAKEFLAGS)))
109 export quiet Q KBUILD_VERBOSE
111 # Call a source code checker (by default, "sparse") as part of the
114 # Use 'make C=1' to enable checking of only re-compiled files.
115 # Use 'make C=2' to enable checking of *all* source files, regardless
116 # of whether they are re-compiled or not.
118 # See the file "Documentation/dev-tools/sparse.rst" for more details,
119 # including where to get the "sparse" utility.
121 ifeq ("$(origin C)", "command line")
122 KBUILD_CHECKSRC = $(C)
124 ifndef KBUILD_CHECKSRC
128 export KBUILD_CHECKSRC
130 # Enable "clippy" (a linter) as part of the Rust compilation.
132 # Use 'make CLIPPY=1' to enable it.
133 ifeq ("$(origin CLIPPY)", "command line")
134 KBUILD_CLIPPY := $(CLIPPY)
139 # Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
140 # directory of external module to build. Setting M= takes precedence.
141 ifeq ("$(origin M)", "command line")
142 KBUILD_EXTMOD := $(M)
145 $(if $(word 2, $(KBUILD_EXTMOD)), \
146 $(error building multiple external modules is not supported))
148 $(foreach x, % :, $(if $(findstring $x, $(KBUILD_EXTMOD)), \
149 $(error module directory path cannot contain '$x')))
151 # Remove trailing slashes
152 ifneq ($(filter %/, $(KBUILD_EXTMOD)),)
153 KBUILD_EXTMOD := $(shell dirname $(KBUILD_EXTMOD).)
158 # Kbuild will save output files in the current working directory.
159 # This does not need to match to the root of the kernel source tree.
161 # For example, you can do this:
163 # cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
165 # If you want to save output files in a different location, there are
166 # two syntaxes to specify it.
169 # Use "make O=dir/to/store/output/files/"
171 # 2) Set KBUILD_OUTPUT
172 # Set the environment variable KBUILD_OUTPUT to point to the output directory.
173 # export KBUILD_OUTPUT=dir/to/store/output/files/; make
175 # The O= assignment takes precedence over the KBUILD_OUTPUT environment
178 # Do we want to change the working directory?
179 ifeq ("$(origin O)", "command line")
180 KBUILD_OUTPUT := $(O)
183 ifneq ($(KBUILD_OUTPUT),)
184 # Make's built-in functions such as $(abspath ...), $(realpath ...) cannot
185 # expand a shell special character '~'. We use a somewhat tedious way here.
186 abs_objtree := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) && pwd)
187 $(if $(abs_objtree),, \
188 $(error failed to create output directory "$(KBUILD_OUTPUT)"))
190 # $(realpath ...) resolves symlinks
191 abs_objtree := $(realpath $(abs_objtree))
193 abs_objtree := $(CURDIR)
194 endif # ifneq ($(KBUILD_OUTPUT),)
196 ifeq ($(abs_objtree),$(CURDIR))
197 # Suppress "Entering directory ..." unless we are changing the work directory.
198 MAKEFLAGS += --no-print-directory
203 this-makefile := $(lastword $(MAKEFILE_LIST))
204 abs_srctree := $(realpath $(dir $(this-makefile)))
206 ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
207 $(error source directory cannot contain spaces or colons)
210 ifneq ($(abs_srctree),$(abs_objtree))
211 # Look for make include files relative to root of kernel src
213 # --included-dir is added for backward compatibility, but you should not rely on
214 # it. Please add $(srctree)/ prefix to include Makefiles in the source tree.
215 MAKEFLAGS += --include-dir=$(abs_srctree)
218 ifneq ($(filter 3.%,$(MAKE_VERSION)),)
219 # 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
220 # We need to invoke sub-make to avoid implicit rules in the top Makefile.
222 # Cancel implicit rules for this Makefile.
226 export abs_srctree abs_objtree
227 export sub_make_done := 1
229 ifeq ($(need-sub-make),1)
231 PHONY += $(MAKECMDGOALS) __sub-make
233 $(filter-out $(this-makefile), $(MAKECMDGOALS)) __all: __sub-make
236 # Invoke a second make in the output directory, passing relevant variables
238 $(Q)$(MAKE) -C $(abs_objtree) -f $(abs_srctree)/Makefile $(MAKECMDGOALS)
240 endif # need-sub-make
241 endif # sub_make_done
243 # We process the rest of the Makefile if this is the final invocation of make
244 ifeq ($(need-sub-make),)
246 # Do not print "Entering directory ...",
247 # but we want to display it when entering to the output directory
248 # so that IDEs/editors are able to understand relative filenames.
249 MAKEFLAGS += --no-print-directory
251 ifeq ($(abs_srctree),$(abs_objtree))
252 # building in the source tree
254 building_out_of_srctree :=
256 ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
257 # building in a subdirectory of the source tree
260 srctree := $(abs_srctree)
262 building_out_of_srctree := 1
265 ifneq ($(KBUILD_ABS_SRCTREE),)
266 srctree := $(abs_srctree)
272 export building_out_of_srctree srctree objtree VPATH
274 # To make sure we do not include .config for any of the *config targets
275 # catch them early, and hand them over to scripts/kconfig/Makefile
276 # It is allowed to specify more targets when calling make, including
277 # mixing *config targets and build targets.
278 # For example 'make oldconfig all'.
279 # Detect when mixed targets is specified, and make a second invocation
280 # of make so .config is not included in this case either (for *config).
282 version_h := include/generated/uapi/linux/version.h
284 clean-targets := %clean mrproper cleandocs
285 no-dot-config-targets := $(clean-targets) \
286 cscope gtags TAGS tags help% %docs check% coccicheck \
287 $(version_h) headers headers_% archheaders archscripts \
288 %asm-generic kernelversion %src-pkg dt_binding_check \
289 outputmakefile rustavailable rustfmt rustfmtcheck
290 # Installation targets should not require compiler. Unfortunately, vdso_install
291 # is an exception where build artifacts may be updated. This must be fixed.
292 no-compiler-targets := $(no-dot-config-targets) install dtbs_install \
293 headers_install modules_install kernelrelease image_name
294 no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease \
296 single-targets := %.a %.i %.rsi %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
305 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
306 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
311 ifneq ($(filter $(no-compiler-targets), $(MAKECMDGOALS)),)
312 ifeq ($(filter-out $(no-compiler-targets), $(MAKECMDGOALS)),)
317 ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
318 ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
323 ifneq ($(KBUILD_EXTMOD),)
327 ifeq ($(KBUILD_EXTMOD),)
328 ifneq ($(filter %config,$(MAKECMDGOALS)),)
330 ifneq ($(words $(MAKECMDGOALS)),1)
336 # We cannot build single targets and the others at the same time
337 ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
339 ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
344 # For "make -j clean all", "make -j mrproper defconfig all", etc.
345 ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
346 ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
351 # install and modules_install need also be processed one by one
352 ifneq ($(filter install,$(MAKECMDGOALS)),)
353 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
359 # ===========================================================================
360 # We're called with mixed targets (*config and build targets).
361 # Handle them one by one.
363 PHONY += $(MAKECMDGOALS) __build_one_by_one
365 $(MAKECMDGOALS): __build_one_by_one
370 for i in $(MAKECMDGOALS); do \
371 $(MAKE) -f $(srctree)/Makefile $$i; \
376 include $(srctree)/scripts/Kbuild.include
378 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
379 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
380 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
381 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
383 include $(srctree)/scripts/subarch.include
385 # Cross compiling and selecting different set of gcc/bin-utils
386 # ---------------------------------------------------------------------------
388 # When performing cross compilation for other architectures ARCH shall be set
389 # to the target architecture. (See arch/* for the possibilities).
390 # ARCH can be set during invocation of make:
392 # Another way is to have ARCH set in the environment.
393 # The default ARCH is the host where make is executed.
395 # CROSS_COMPILE specify the prefix used for all executables used
396 # during compilation. Only gcc and related bin-utils executables
397 # are prefixed with $(CROSS_COMPILE).
398 # CROSS_COMPILE can be set on the command line
399 # make CROSS_COMPILE=ia64-linux-
400 # Alternatively CROSS_COMPILE can be set in the environment.
401 # Default value for CROSS_COMPILE is not to prefix executables
402 # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
405 # Architecture as present in compile.h
406 UTS_MACHINE := $(ARCH)
409 # Additional ARCH settings for x86
413 ifeq ($(ARCH),x86_64)
417 # Additional ARCH settings for sparc
418 ifeq ($(ARCH),sparc32)
421 ifeq ($(ARCH),sparc64)
425 # Additional ARCH settings for parisc
426 ifeq ($(ARCH),parisc64)
430 export cross_compiling :=
431 ifneq ($(SRCARCH),$(SUBARCH))
435 KCONFIG_CONFIG ?= .config
436 export KCONFIG_CONFIG
438 # SHELL used by kbuild
441 HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
442 HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
443 HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
446 ifneq ($(filter %/,$(LLVM)),)
447 LLVM_PREFIX := $(LLVM)
448 else ifneq ($(filter -%,$(LLVM)),)
449 LLVM_SUFFIX := $(LLVM)
452 HOSTCC = $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
453 HOSTCXX = $(LLVM_PREFIX)clang++$(LLVM_SUFFIX)
459 HOSTPKG_CONFIG = pkg-config
461 KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
462 -O2 -fomit-frame-pointer -std=gnu11
463 KBUILD_USERCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(USERCFLAGS)
464 KBUILD_USERLDFLAGS := $(USERLDFLAGS)
466 # These flags apply to all Rust code in the tree, including the kernel and
468 export rust_common_flags := --edition=2021 \
469 -Zbinary_dep_depinfo=y \
470 -Dunsafe_op_in_unsafe_fn -Drust_2018_idioms \
471 -Dunreachable_pub -Dnon_ascii_idents \
473 -Drustdoc::missing_crate_level_docs \
474 -Dclippy::correctness -Dclippy::style \
475 -Dclippy::suspicious -Dclippy::complexity \
477 -Dclippy::let_unit_value -Dclippy::mut_mut \
478 -Dclippy::needless_bitwise_bool \
479 -Dclippy::needless_continue \
482 KBUILD_HOSTCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
483 KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
484 KBUILD_HOSTRUSTFLAGS := $(rust_common_flags) -O -Cstrip=debuginfo \
485 -Zallow-features= $(HOSTRUSTFLAGS)
486 KBUILD_HOSTLDFLAGS := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
487 KBUILD_HOSTLDLIBS := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
489 # Make variables (CC, etc...)
492 CC = $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
493 LD = $(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX)
494 AR = $(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX)
495 NM = $(LLVM_PREFIX)llvm-nm$(LLVM_SUFFIX)
496 OBJCOPY = $(LLVM_PREFIX)llvm-objcopy$(LLVM_SUFFIX)
497 OBJDUMP = $(LLVM_PREFIX)llvm-objdump$(LLVM_SUFFIX)
498 READELF = $(LLVM_PREFIX)llvm-readelf$(LLVM_SUFFIX)
499 STRIP = $(LLVM_PREFIX)llvm-strip$(LLVM_SUFFIX)
501 CC = $(CROSS_COMPILE)gcc
502 LD = $(CROSS_COMPILE)ld
503 AR = $(CROSS_COMPILE)ar
504 NM = $(CROSS_COMPILE)nm
505 OBJCOPY = $(CROSS_COMPILE)objcopy
506 OBJDUMP = $(CROSS_COMPILE)objdump
507 READELF = $(CROSS_COMPILE)readelf
508 STRIP = $(CROSS_COMPILE)strip
513 CLIPPY_DRIVER = clippy-driver
517 RESOLVE_BTFIDS = $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
521 INSTALLKERNEL := installkernel
535 PAHOLE_FLAGS = $(shell PAHOLE=$(PAHOLE) $(srctree)/scripts/pahole-flags.sh)
537 CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
538 -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
549 # Use USERINCLUDE when you must reference the UAPI directories only.
551 -I$(srctree)/arch/$(SRCARCH)/include/uapi \
552 -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
553 -I$(srctree)/include/uapi \
554 -I$(objtree)/include/generated/uapi \
555 -include $(srctree)/include/linux/compiler-version.h \
556 -include $(srctree)/include/linux/kconfig.h
558 # Use LINUXINCLUDE when you must reference the include/ directory.
559 # Needed to be compatible with the O= option
561 -I$(srctree)/arch/$(SRCARCH)/include \
562 -I$(objtree)/arch/$(SRCARCH)/include/generated \
563 $(if $(building_out_of_srctree),-I$(srctree)/include) \
564 -I$(objtree)/include \
567 KBUILD_AFLAGS := -D__ASSEMBLY__ -fno-PIE
568 KBUILD_CFLAGS := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
569 -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
570 -Werror=implicit-function-declaration -Werror=implicit-int \
571 -Werror=return-type -Wno-format-security \
573 KBUILD_CPPFLAGS := -D__KERNEL__
574 KBUILD_RUSTFLAGS := $(rust_common_flags) \
575 --target=$(objtree)/rust/target.json \
576 -Cpanic=abort -Cembed-bitcode=n -Clto=n \
577 -Cforce-unwind-tables=n -Ccodegen-units=1 \
578 -Csymbol-mangling-version=v0 \
579 -Crelocation-model=static \
580 -Zfunction-sections=n \
581 -Dclippy::float_arithmetic
583 KBUILD_AFLAGS_KERNEL :=
584 KBUILD_CFLAGS_KERNEL :=
585 KBUILD_RUSTFLAGS_KERNEL :=
586 KBUILD_AFLAGS_MODULE := -DMODULE
587 KBUILD_CFLAGS_MODULE := -DMODULE
588 KBUILD_RUSTFLAGS_MODULE := --cfg MODULE
589 KBUILD_LDFLAGS_MODULE :=
593 ifeq ($(KBUILD_CLIPPY),1)
594 RUSTC_OR_CLIPPY_QUIET := CLIPPY
595 RUSTC_OR_CLIPPY = $(CLIPPY_DRIVER)
597 RUSTC_OR_CLIPPY_QUIET := RUSTC
598 RUSTC_OR_CLIPPY = $(RUSTC)
605 # Allows the usage of unstable features in stable compilers.
606 export RUSTC_BOOTSTRAP := 1
608 export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG
609 export RUSTC RUSTDOC RUSTFMT RUSTC_OR_CLIPPY_QUIET RUSTC_OR_CLIPPY BINDGEN CARGO
610 export HOSTRUSTC KBUILD_HOSTRUSTFLAGS
611 export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
612 export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
613 export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
614 export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
615 export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS
617 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
618 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
619 export KBUILD_RUSTFLAGS RUSTFLAGS_KERNEL RUSTFLAGS_MODULE
620 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
621 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_RUSTFLAGS_MODULE KBUILD_LDFLAGS_MODULE
622 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL KBUILD_RUSTFLAGS_KERNEL
625 # Files to ignore in find ... statements
627 export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o \
628 -name CVS -o -name .pc -o -name .hg -o -name .git \) \
630 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
631 --exclude CVS --exclude .pc --exclude .hg --exclude .git
633 # ===========================================================================
634 # Rules shared between *config targets and build targets
636 # Basic helpers built in scripts/basic/
637 PHONY += scripts_basic
639 $(Q)$(MAKE) $(build)=scripts/basic
641 PHONY += outputmakefile
642 ifdef building_out_of_srctree
643 # Before starting out-of-tree build, make sure the source tree is clean.
644 # outputmakefile generates a Makefile in the output directory, if using a
645 # separate output directory. This allows convenient use of make in the
647 # At the same time when output Makefile generated, generate .gitignore to
648 # ignore whole output directory
650 quiet_cmd_makefile = GEN Makefile
652 echo "\# Automatically generated by $(srctree)/Makefile: don't edit"; \
653 echo "include $(srctree)/Makefile"; \
657 @if [ -f $(srctree)/.config -o \
658 -d $(srctree)/include/config -o \
659 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
661 echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
662 echo >&2 "*** in $(abs_srctree)";\
666 $(Q)ln -fsn $(srctree) source
668 $(Q)test -e .gitignore || \
669 { echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
672 # The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
673 # Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
674 # CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
675 # and from include/config/auto.conf.cmd to detect the compiler upgrade.
676 CC_VERSION_TEXT = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1))
678 ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
679 include $(srctree)/scripts/Makefile.clang
682 # Include this also for config targets because some architectures need
683 # cc-cross-prefix to determine CROSS_COMPILE.
685 include $(srctree)/scripts/Makefile.compiler
689 # ===========================================================================
690 # *config targets only - make sure prerequisites are updated, and descend
691 # in scripts/kconfig to make the *config target
693 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
694 # KBUILD_DEFCONFIG may point out an alternative default configuration
695 # used for 'make defconfig'
696 include $(srctree)/arch/$(SRCARCH)/Makefile
697 export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
699 config: outputmakefile scripts_basic FORCE
700 $(Q)$(MAKE) $(build)=scripts/kconfig $@
702 %config: outputmakefile scripts_basic FORCE
703 $(Q)$(MAKE) $(build)=scripts/kconfig $@
706 # ===========================================================================
707 # Build targets only - this includes vmlinux, arch specific targets, clean
708 # targets and others. In general all targets except *config targets.
710 # If building an external module we do not care about the all: rule
711 # but instead __all depend on modules
713 ifeq ($(KBUILD_EXTMOD),)
721 # Decide whether to build built-in, modular, or both.
722 # Normally, just do built-in.
727 # If we have only "make modules", don't compile built-in objects.
728 ifeq ($(MAKECMDGOALS),modules)
732 # If we have "make <whatever> modules", compile modules
733 # in addition to whatever we do anyway.
734 # Just "make" or "make all" shall build modules as well
736 ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
740 ifeq ($(MAKECMDGOALS),)
744 export KBUILD_MODULES KBUILD_BUILTIN
747 include include/config/auto.conf
750 ifeq ($(KBUILD_EXTMOD),)
751 # Objects we will link into vmlinux / subdirs we need to visit
755 endif # KBUILD_EXTMOD
757 # The all: target is the default when no target is given on the
759 # This allow a user to issue only 'make' to build a kernel including modules
760 # Defaults to vmlinux, but the arch makefile usually adds further targets
763 CFLAGS_GCOV := -fprofile-arcs -ftest-coverage
764 ifdef CONFIG_CC_IS_GCC
765 CFLAGS_GCOV += -fno-tree-loop-im
769 # The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
770 ifdef CONFIG_FUNCTION_TRACER
771 CC_FLAGS_FTRACE := -pg
774 include $(srctree)/arch/$(SRCARCH)/Makefile
777 ifdef may-sync-config
778 # Read in dependencies to all Kconfig* files, make sure to run syncconfig if
779 # changes are detected. This should be included after arch/$(SRCARCH)/Makefile
780 # because some architectures define CROSS_COMPILE there.
781 include include/config/auto.conf.cmd
785 @echo >&2 '*** Configuration file "$@" not found!'
787 @echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
788 @echo >&2 '*** "make menuconfig" or "make xconfig").'
792 # The actual configuration files used during the build are stored in
793 # include/generated/ and include/config/. Update them if .config is newer than
794 # include/config/auto.conf (which mirrors .config).
796 # This exploits the 'multi-target pattern rule' trick.
797 # The syncconfig should be executed only once to make all the targets.
798 # (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
800 # Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
801 # so you cannot notice that Kconfig is waiting for the user input.
802 %/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h %/generated/rustc_cfg: $(KCONFIG_CONFIG)
803 $(Q)$(kecho) " SYNC $@"
804 $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
805 else # !may-sync-config
806 # External modules and some install targets need include/generated/autoconf.h
807 # and include/config/auto.conf but do not care if they are up-to-date.
808 # Use auto.conf to trigger the test
809 PHONY += include/config/auto.conf
811 include/config/auto.conf:
812 @test -e include/generated/autoconf.h -a -e $@ || ( \
814 echo >&2 " ERROR: Kernel configuration is invalid."; \
815 echo >&2 " include/generated/autoconf.h or $@ are missing.";\
816 echo >&2 " Run 'make oldconfig && make prepare' on kernel src to fix it."; \
820 endif # may-sync-config
823 KBUILD_CFLAGS += -fno-delete-null-pointer-checks
824 KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,)
825 KBUILD_CFLAGS += $(call cc-disable-warning, format-truncation)
826 KBUILD_CFLAGS += $(call cc-disable-warning, format-overflow)
827 KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
829 ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
831 KBUILD_RUSTFLAGS += -Copt-level=2
832 else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
834 KBUILD_RUSTFLAGS += -Copt-level=s
837 # Always set `debug-assertions` and `overflow-checks` because their default
838 # depends on `opt-level` and `debug-assertions`, respectively.
839 KBUILD_RUSTFLAGS += -Cdebug-assertions=$(if $(CONFIG_RUST_DEBUG_ASSERTIONS),y,n)
840 KBUILD_RUSTFLAGS += -Coverflow-checks=$(if $(CONFIG_RUST_OVERFLOW_CHECKS),y,n)
842 # Tell gcc to never replace conditional load with a non-conditional one
843 ifdef CONFIG_CC_IS_GCC
844 # gcc-10 renamed --param=allow-store-data-races=0 to
845 # -fno-allow-store-data-races.
846 KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
847 KBUILD_CFLAGS += $(call cc-option,-fno-allow-store-data-races)
850 ifdef CONFIG_READABLE_ASM
851 # Disable optimizations that make assembler listings hard to read.
852 # reorder blocks reorders the control in the function
853 # ipa clone creates specialized cloned functions
854 # partial inlining inlines only parts of functions
855 KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
858 ifneq ($(CONFIG_FRAME_WARN),0)
859 KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
862 stackp-flags-y := -fno-stack-protector
863 stackp-flags-$(CONFIG_STACKPROTECTOR) := -fstack-protector
864 stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG) := -fstack-protector-strong
866 KBUILD_CFLAGS += $(stackp-flags-y)
868 KBUILD_CFLAGS-$(CONFIG_WERROR) += -Werror -Wno-error=format-extra-args -Wno-error=comment -Wno-error=unused-function -Wno-error=unused-variable
869 KBUILD_CFLAGS-$(CONFIG_CC_NO_ARRAY_BOUNDS) += -Wno-array-bounds
871 KBUILD_RUSTFLAGS-$(CONFIG_WERROR) += -Dwarnings
872 KBUILD_RUSTFLAGS += $(KBUILD_RUSTFLAGS-y)
874 ifdef CONFIG_CC_IS_CLANG
875 KBUILD_CPPFLAGS += -Qunused-arguments
876 # The kernel builds with '-std=gnu11' so use of GNU extensions is acceptable.
877 KBUILD_CFLAGS += -Wno-gnu
880 # gcc inanely warns about local variables called 'main'
881 KBUILD_CFLAGS += -Wno-main
884 # These warnings generated too much noise in a regular build.
885 # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
886 KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
887 KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
889 # These result in bogus false positives
890 KBUILD_CFLAGS += $(call cc-disable-warning, dangling-pointer)
892 ifdef CONFIG_FRAME_POINTER
893 KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
894 KBUILD_RUSTFLAGS += -Cforce-frame-pointers=y
896 # Some targets (ARM with Thumb2, for example), can't be built with frame
897 # pointers. For those, we don't have FUNCTION_TRACER automatically
898 # select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
899 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
900 # -fomit-frame-pointer with FUNCTION_TRACER.
901 # In the Rust target specification, "frame-pointer" is set explicitly
903 ifndef CONFIG_FUNCTION_TRACER
904 KBUILD_CFLAGS += -fomit-frame-pointer
908 # Initialize all stack variables with a 0xAA pattern.
909 ifdef CONFIG_INIT_STACK_ALL_PATTERN
910 KBUILD_CFLAGS += -ftrivial-auto-var-init=pattern
913 # Initialize all stack variables with a zero value.
914 ifdef CONFIG_INIT_STACK_ALL_ZERO
915 KBUILD_CFLAGS += -ftrivial-auto-var-init=zero
916 ifdef CONFIG_CC_HAS_AUTO_VAR_INIT_ZERO_ENABLER
917 # https://github.com/llvm/llvm-project/issues/44842
918 KBUILD_CFLAGS += -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
922 # While VLAs have been removed, GCC produces unreachable stack probes
923 # for the randomize_kstack_offset feature. Disable it for all compilers.
924 KBUILD_CFLAGS += $(call cc-option, -fno-stack-clash-protection)
926 # Clear used registers at func exit (to reduce data lifetime and ROP gadgets).
927 ifdef CONFIG_ZERO_CALL_USED_REGS
928 KBUILD_CFLAGS += -fzero-call-used-regs=used-gpr
931 ifdef CONFIG_FUNCTION_TRACER
932 ifdef CONFIG_FTRACE_MCOUNT_USE_CC
933 CC_FLAGS_FTRACE += -mrecord-mcount
934 ifdef CONFIG_HAVE_NOP_MCOUNT
935 ifeq ($(call cc-option-yn, -mnop-mcount),y)
936 CC_FLAGS_FTRACE += -mnop-mcount
937 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
941 ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
942 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
944 ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
945 ifdef CONFIG_HAVE_C_RECORDMCOUNT
946 BUILD_C_RECORDMCOUNT := y
947 export BUILD_C_RECORDMCOUNT
950 ifdef CONFIG_HAVE_FENTRY
951 # s390-linux-gnu-gcc did not support -mfentry until gcc-9.
952 ifeq ($(call cc-option-yn, -mfentry),y)
953 CC_FLAGS_FTRACE += -mfentry
954 CC_FLAGS_USING += -DCC_USING_FENTRY
957 export CC_FLAGS_FTRACE
958 KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
959 KBUILD_AFLAGS += $(CC_FLAGS_USING)
962 # We trigger additional mismatches with less inlining
963 ifdef CONFIG_DEBUG_SECTION_MISMATCH
964 KBUILD_CFLAGS += -fno-inline-functions-called-once
967 # `rustc`'s `-Zfunction-sections` applies to data too (as of 1.59.0).
968 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
969 KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
970 KBUILD_RUSTFLAGS_KERNEL += -Zfunction-sections=y
971 LDFLAGS_vmlinux += --gc-sections
974 ifdef CONFIG_SHADOW_CALL_STACK
975 CC_FLAGS_SCS := -fsanitize=shadow-call-stack
976 KBUILD_CFLAGS += $(CC_FLAGS_SCS)
980 ifdef CONFIG_LTO_CLANG
981 ifdef CONFIG_LTO_CLANG_THIN
982 CC_FLAGS_LTO := -flto=thin -fsplit-lto-unit
983 KBUILD_LDFLAGS += --thinlto-cache-dir=$(extmod_prefix).thinlto-cache
985 CC_FLAGS_LTO := -flto
987 CC_FLAGS_LTO += -fvisibility=hidden
989 # Limit inlining across translation units to reduce binary size
990 KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
992 # Check for frame size exceeding threshold during prolog/epilog insertion
993 # when using lld < 13.0.0.
994 ifneq ($(CONFIG_FRAME_WARN),0)
995 ifeq ($(shell test $(CONFIG_LLD_VERSION) -lt 130000; echo $$?),0)
996 KBUILD_LDFLAGS += -plugin-opt=-warn-stack-size=$(CONFIG_FRAME_WARN)
1002 KBUILD_CFLAGS += -fno-lto $(CC_FLAGS_LTO)
1003 KBUILD_AFLAGS += -fno-lto
1007 ifdef CONFIG_CFI_CLANG
1008 CC_FLAGS_CFI := -fsanitize=kcfi
1009 KBUILD_CFLAGS += $(CC_FLAGS_CFI)
1013 ifdef CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_64B
1014 KBUILD_CFLAGS += -falign-functions=64
1017 # arch Makefile may override CC so keep this after arch Makefile is included
1018 NOSTDINC_FLAGS += -nostdinc
1020 # Variable Length Arrays (VLAs) should not be used anywhere in the kernel
1021 KBUILD_CFLAGS += -Wvla
1023 # disable pointer signed / unsigned warnings in gcc 4.0
1024 KBUILD_CFLAGS += -Wno-pointer-sign
1026 # In order to make sure new function cast mismatches are not introduced
1027 # in the kernel (to avoid tripping CFI checking), the kernel should be
1028 # globally built with -Wcast-function-type.
1029 KBUILD_CFLAGS += $(call cc-option, -Wcast-function-type)
1031 # disable stringop warnings in gcc 8+
1032 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
1034 # We'll want to enable this eventually, but it's not going away for 5.7 at least
1035 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
1037 # Another good warning that we'll want to enable eventually
1038 KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
1040 # Enabled with W=2, disabled by default as noisy
1041 ifdef CONFIG_CC_IS_GCC
1042 KBUILD_CFLAGS += -Wno-maybe-uninitialized
1045 # The allocators already balk at large sizes, so silence the compiler
1046 # warnings for bounds checks involving those possible values. While
1047 # -Wno-alloc-size-larger-than would normally be used here, earlier versions
1048 # of gcc (<9.1) weirdly don't handle the option correctly when _other_
1049 # warnings are produced (?!). Using -Walloc-size-larger-than=SIZE_MAX
1050 # doesn't work (as it is documented to), silently resolving to "0" prior to
1051 # version 9.1 (and producing an error more recently). Numeric values larger
1052 # than PTRDIFF_MAX also don't work prior to version 9.1, which are silently
1053 # ignored, continuing to default to PTRDIFF_MAX. So, left with no other
1054 # choice, we must perform a versioned check to disable this warning.
1055 # https://lore.kernel.org/lkml/20210824115859.187f272f@canb.auug.org.au
1056 KBUILD_CFLAGS-$(call gcc-min-version, 90100) += -Wno-alloc-size-larger-than
1057 KBUILD_CFLAGS += $(KBUILD_CFLAGS-y) $(CONFIG_CC_IMPLICIT_FALLTHROUGH)
1059 # disable invalid "can't wrap" optimizations for signed / pointers
1060 KBUILD_CFLAGS += -fno-strict-overflow
1062 # Make sure -fstack-check isn't enabled (like gentoo apparently did)
1063 KBUILD_CFLAGS += -fno-stack-check
1065 # conserve stack if available
1066 ifdef CONFIG_CC_IS_GCC
1067 KBUILD_CFLAGS += -fconserve-stack
1070 # Prohibit date/time macros, which would make the build non-deterministic
1071 KBUILD_CFLAGS += -Werror=date-time
1073 # enforce correct pointer usage
1074 KBUILD_CFLAGS += $(call cc-option,-Werror=incompatible-pointer-types)
1076 # Require designated initializers for all marked structures
1077 KBUILD_CFLAGS += $(call cc-option,-Werror=designated-init)
1079 # change __FILE__ to the relative path from the srctree
1080 KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
1082 # include additional Makefiles when needed
1083 include-y := scripts/Makefile.extrawarn
1084 include-$(CONFIG_DEBUG_INFO) += scripts/Makefile.debug
1085 include-$(CONFIG_KASAN) += scripts/Makefile.kasan
1086 include-$(CONFIG_KCSAN) += scripts/Makefile.kcsan
1087 include-$(CONFIG_KMSAN) += scripts/Makefile.kmsan
1088 include-$(CONFIG_UBSAN) += scripts/Makefile.ubsan
1089 include-$(CONFIG_KCOV) += scripts/Makefile.kcov
1090 include-$(CONFIG_RANDSTRUCT) += scripts/Makefile.randstruct
1091 include-$(CONFIG_GCC_PLUGINS) += scripts/Makefile.gcc-plugins
1093 include $(addprefix $(srctree)/, $(include-y))
1095 # scripts/Makefile.gcc-plugins is intentionally included last.
1096 # Do not add $(call cc-option,...) below this line. When you build the kernel
1097 # from the clean source tree, the GCC plugins do not exist at this point.
1099 # Add user supplied CPPFLAGS, AFLAGS, CFLAGS and RUSTFLAGS as the last assignments
1100 KBUILD_CPPFLAGS += $(KCPPFLAGS)
1101 KBUILD_AFLAGS += $(KAFLAGS)
1102 KBUILD_CFLAGS += $(KCFLAGS)
1103 KBUILD_RUSTFLAGS += $(KRUSTFLAGS)
1105 KBUILD_LDFLAGS_MODULE += --build-id=sha1
1106 LDFLAGS_vmlinux += --build-id=sha1
1108 KBUILD_LDFLAGS += -z noexecstack
1109 ifeq ($(CONFIG_LD_IS_BFD),y)
1110 KBUILD_LDFLAGS += $(call ld-option,--no-warn-rwx-segments)
1113 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1114 LDFLAGS_vmlinux += -X
1117 ifeq ($(CONFIG_RELR),y)
1118 LDFLAGS_vmlinux += --pack-dyn-relocs=relr --use-android-relr-tags
1121 # We never want expected sections to be placed heuristically by the
1122 # linker. All sections should be explicitly named in the linker script.
1123 ifdef CONFIG_LD_ORPHAN_WARN
1124 LDFLAGS_vmlinux += --orphan-handling=warn
1127 # Align the bit size of userspace programs with the kernel
1128 KBUILD_USERCFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1129 KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1131 # make the checker run with the right architecture
1132 CHECKFLAGS += --arch=$(ARCH)
1134 # insure the checker run with the right endianness
1135 CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1137 # the checker needs the correct machine size
1138 CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1140 # Default kernel image to build when no specific target is given.
1141 # KBUILD_IMAGE may be overruled on the command line or
1142 # set in the environment
1143 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
1144 # this default value
1145 export KBUILD_IMAGE ?= vmlinux
1148 # INSTALL_PATH specifies where to place the updated kernel and system map
1149 # images. Default is /boot, but you can set it to other values
1150 export INSTALL_PATH ?= /boot
1153 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1154 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1155 # an argument if needed. Otherwise it defaults to the kernel install path
1157 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1160 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1161 # relocations required by build roots. This is not defined in the
1162 # makefile but the argument can be passed to make if needed.
1165 MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1170 export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
1171 export MODORDER := $(extmod_prefix)modules.order
1172 export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
1174 ifeq ($(KBUILD_EXTMOD),)
1177 clean-dirs := $(sort . Documentation \
1178 $(patsubst %/,%,$(filter %/, $(core-) \
1179 $(drivers-) $(libs-))))
1181 export ARCH_CORE := $(core-y)
1182 export ARCH_LIB := $(filter %/, $(libs-y))
1183 export ARCH_DRIVERS := $(drivers-y) $(drivers-m)
1184 # Externally visible symbols (used by link-vmlinux.sh)
1186 KBUILD_VMLINUX_OBJS := ./built-in.a
1187 ifdef CONFIG_MODULES
1188 KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1189 KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1191 KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1194 export KBUILD_VMLINUX_LIBS
1195 export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
1197 # Recurse until adjust_autoksyms.sh is satisfied
1198 PHONY += autoksyms_recursive
1199 ifdef CONFIG_TRIM_UNUSED_KSYMS
1200 # For the kernel to actually contain only the needed exported symbols,
1201 # we have to build modules as well to determine what those symbols are.
1202 # (this can be evaluated only once include/config/auto.conf has been included)
1205 autoksyms_recursive: $(build-dir) modules.order
1206 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1207 "$(MAKE) -f $(srctree)/Makefile autoksyms_recursive"
1210 autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1212 quiet_cmd_autoksyms_h = GEN $@
1213 cmd_autoksyms_h = mkdir -p $(dir $@); \
1214 $(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@
1217 $(call cmd,autoksyms_h)
1219 # '$(AR) mPi' needs 'T' to workaround the bug of llvm-ar <= 14
1220 quiet_cmd_ar_vmlinux.a = AR $@
1221 cmd_ar_vmlinux.a = \
1223 $(AR) cDPrST $@ $(KBUILD_VMLINUX_OBJS); \
1224 $(AR) mPiT $$($(AR) t $@ | sed -n 1p) $@ $$($(AR) t $@ | grep -F -f $(srctree)/scripts/head-object-list.txt)
1226 targets += vmlinux.a
1227 vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt autoksyms_recursive FORCE
1228 $(call if_changed,ar_vmlinux.a)
1231 vmlinux_o: vmlinux.a $(KBUILD_VMLINUX_LIBS)
1232 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o
1234 vmlinux.o modules.builtin.modinfo modules.builtin: vmlinux_o
1238 # LDFLAGS_vmlinux in the top Makefile defines linker flags for the top vmlinux,
1239 # not for decompressors. LDFLAGS_vmlinux in arch/*/boot/compressed/Makefile is
1240 # unrelated; the decompressors just happen to have the same base name,
1241 # arch/*/boot/compressed/vmlinux.
1242 # Export LDFLAGS_vmlinux only to scripts/Makefile.vmlinux.
1244 # _LDFLAGS_vmlinux is a workaround for the 'private export' bug:
1245 # https://savannah.gnu.org/bugs/?61463
1246 # For Make > 4.4, the following simple code will work:
1247 # vmlinux: private export LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1248 vmlinux: private _LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1249 vmlinux: export LDFLAGS_vmlinux = $(_LDFLAGS_vmlinux)
1250 vmlinux: vmlinux.o $(KBUILD_LDS) modpost
1251 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux
1253 # The actual objects are generated when descending,
1254 # make sure no implicit rule kicks in
1255 $(sort $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)): . ;
1257 filechk_kernel.release = \
1258 echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1260 # Store (new) KERNELRELEASE string in include/config/kernel.release
1261 include/config/kernel.release: FORCE
1262 $(call filechk,kernel.release)
1264 # Additional helpers built in scripts/
1265 # Carefully list dependencies so we do not try to build scripts twice
1268 scripts: scripts_basic scripts_dtc
1269 $(Q)$(MAKE) $(build)=$(@)
1271 # Things we need to do before we recursively start building the kernel
1272 # or the modules are listed in "prepare".
1273 # A multi level approach is used. prepareN is processed before prepareN-1.
1274 # archprepare is used in arch Makefiles and when processed asm symlink,
1275 # version.h and scripts_basic is processed / created.
1277 PHONY += prepare archprepare
1279 archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1280 asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h \
1281 include/generated/compile.h include/generated/autoconf.h remove-stale-files
1283 prepare0: archprepare
1284 $(Q)$(MAKE) $(build)=scripts/mod
1285 $(Q)$(MAKE) $(build)=. prepare
1287 # All the preparing..
1290 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh
1291 $(Q)$(MAKE) $(build)=rust
1294 PHONY += remove-stale-files
1296 $(Q)$(srctree)/scripts/remove-stale-files
1298 # Support for using generic headers in asm-generic
1299 asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1301 PHONY += asm-generic uapi-asm-generic
1302 asm-generic: uapi-asm-generic
1303 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1304 generic=include/asm-generic
1306 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1307 generic=include/uapi/asm-generic
1309 # Generate some files
1310 # ---------------------------------------------------------------------------
1312 # KERNELRELEASE can change from a few different places, meaning version.h
1313 # needs to be updated, so this check is forced on all builds
1316 define filechk_utsrelease.h
1317 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1318 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1321 echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1324 define filechk_version.h
1325 if [ $(SUBLEVEL) -gt 255 ]; then \
1326 echo \#define LINUX_VERSION_CODE $(shell \
1327 expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1329 echo \#define LINUX_VERSION_CODE $(shell \
1330 expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1332 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + \
1333 ((c) > 255 ? 255 : (c)))'; \
1334 echo \#define LINUX_VERSION_MAJOR $(VERSION); \
1335 echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL); \
1336 echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1339 $(version_h): PATCHLEVEL := $(or $(PATCHLEVEL), 0)
1340 $(version_h): SUBLEVEL := $(or $(SUBLEVEL), 0)
1342 $(call filechk,version.h)
1344 include/generated/utsrelease.h: include/config/kernel.release FORCE
1345 $(call filechk,utsrelease.h)
1347 filechk_compile.h = $(srctree)/scripts/mkcompile_h \
1348 "$(UTS_MACHINE)" "$(CONFIG_CC_VERSION_TEXT)" "$(LD)"
1350 include/generated/compile.h: FORCE
1351 $(call filechk,compile.h)
1355 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1356 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1358 # ---------------------------------------------------------------------------
1361 #Default location for installed headers
1362 export INSTALL_HDR_PATH = $(objtree)/usr
1364 quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1365 cmd_headers_install = \
1366 mkdir -p $(INSTALL_HDR_PATH); \
1367 rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1368 usr/include $(INSTALL_HDR_PATH)
1370 PHONY += headers_install
1371 headers_install: headers
1372 $(call cmd,headers_install)
1374 PHONY += archheaders archscripts
1376 hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1379 headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1380 $(if $(filter um, $(SRCARCH)), $(error Headers not exportable for UML))
1381 $(Q)$(MAKE) $(hdr-inst)=include/uapi
1382 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1384 ifdef CONFIG_HEADERS_INSTALL
1388 PHONY += scripts_unifdef
1389 scripts_unifdef: scripts_basic
1390 $(Q)$(MAKE) $(build)=scripts scripts/unifdef
1392 # ---------------------------------------------------------------------------
1395 # Many distributions have the custom install script, /sbin/installkernel.
1396 # If DKMS is installed, 'make install' will eventually recurse back
1397 # to this Makefile to build and install external modules.
1398 # Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
1400 quiet_cmd_install = INSTALL $(INSTALL_PATH)
1401 cmd_install = unset sub_make_done; $(srctree)/scripts/install.sh
1403 # ---------------------------------------------------------------------------
1406 ifdef CONFIG_OBJTOOL
1407 prepare: tools/objtool
1411 ifdef CONFIG_DEBUG_INFO_BTF
1412 prepare: tools/bpf/resolve_btfids
1416 PHONY += resolve_btfids_clean
1418 resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1420 # tools/bpf/resolve_btfids directory might not exist
1421 # in output directory, skip its clean in that case
1422 resolve_btfids_clean:
1423 ifneq ($(wildcard $(resolve_btfids_O)),)
1424 $(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1427 # Clear a bunch of variables before executing the submake
1428 ifeq ($(quiet),silent_)
1433 $(Q)mkdir -p $(objtree)/tools
1434 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1437 $(Q)mkdir -p $(objtree)/tools
1438 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1440 # ---------------------------------------------------------------------------
1445 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1447 kselftest-%: headers FORCE
1448 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1450 PHONY += kselftest-merge
1452 $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1453 $(Q)find $(srctree)/tools/testing/selftests -name config | \
1454 xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1455 $(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1457 # ---------------------------------------------------------------------------
1460 ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1461 dtstree := arch/$(SRCARCH)/boot/dts
1467 $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1469 %.dtbo: dtbs_prepare
1470 $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1472 PHONY += dtbs dtbs_prepare dtbs_install dtbs_check
1474 $(Q)$(MAKE) $(build)=$(dtstree)
1476 # include/config/kernel.release is actually needed when installing DTBs because
1477 # INSTALL_DTBS_PATH contains $(KERNELRELEASE). However, we do not want to make
1478 # dtbs_install depend on it as dtbs_install may run as root.
1479 dtbs_prepare: include/config/kernel.release scripts_dtc
1481 ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1483 dtbs: dt_binding_check
1489 $(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1491 ifdef CONFIG_OF_EARLY_FLATTREE
1497 PHONY += scripts_dtc
1498 scripts_dtc: scripts_basic
1499 $(Q)$(MAKE) $(build)=scripts/dtc
1501 ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1502 export CHECK_DT_BINDING=y
1505 PHONY += dt_binding_check
1506 dt_binding_check: scripts_dtc
1507 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1509 PHONY += dt_compatible_check
1510 dt_compatible_check: dt_binding_check
1511 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1513 # ---------------------------------------------------------------------------
1516 ifdef CONFIG_MODULES
1518 # By default, build modules as well
1522 # When we're building modules with modversions, we need to consider
1523 # the built-in objects during the descend as well, in order to
1524 # make sure the checksums are up to date before we record them.
1525 ifdef CONFIG_MODVERSIONS
1532 # *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFOBTF_MODULES
1534 ifdef CONFIG_DEBUG_INFO_BTF_MODULES
1539 modules: modules_prepare
1541 # Target to prepare building external modules
1542 modules_prepare: prepare
1543 $(Q)$(MAKE) $(build)=scripts scripts/module.lds
1545 export modules_sign_only :=
1547 ifeq ($(CONFIG_MODULE_SIG),y)
1548 PHONY += modules_sign
1549 modules_sign: modules_install
1552 # modules_sign is a subset of modules_install.
1553 # 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1554 ifeq ($(filter modules_install,$(MAKECMDGOALS)),)
1555 modules_sign_only := y
1560 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
1561 modinst_pre := __modinst_pre
1564 modules_install: $(modinst_pre)
1565 PHONY += __modinst_pre
1567 @rm -rf $(MODLIB)/kernel
1568 @rm -f $(MODLIB)/source
1569 @mkdir -p $(MODLIB)/kernel
1570 @ln -s $(abspath $(srctree)) $(MODLIB)/source
1571 @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
1572 rm -f $(MODLIB)/build ; \
1573 ln -s $(CURDIR) $(MODLIB)/build ; \
1575 @sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order
1576 @cp -f modules.builtin $(MODLIB)/
1577 @cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
1579 endif # CONFIG_MODULES
1582 # Cleaning is done on three levels.
1583 # make clean Delete most generated files
1584 # Leave enough to build external modules
1585 # make mrproper Delete the current configuration, and all generated files
1586 # make distclean Remove editor backup files, patch leftover files and the like
1588 # Directories & files removed with 'make clean'
1589 CLEAN_FILES += include/ksym vmlinux.symvers modules-only.symvers \
1590 modules.builtin modules.builtin.modinfo modules.nsdeps \
1591 compile_commands.json .thinlto-cache rust/test rust/doc \
1592 .vmlinux.objs .vmlinux.export.c
1594 # Directories & files removed with 'make mrproper'
1595 MRPROPER_FILES += include/config include/generated \
1596 arch/$(SRCARCH)/include/generated .objdiff \
1597 debian snap tar-install \
1598 .config .config.old .version \
1600 certs/signing_key.pem \
1604 rust/target.json rust/libmacros.so
1606 # clean - Delete most, but leave enough to build external modules
1608 clean: rm-files := $(CLEAN_FILES)
1610 PHONY += archclean vmlinuxclean
1613 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1614 $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1616 clean: archclean vmlinuxclean resolve_btfids_clean
1618 # mrproper - Delete all generated files, including .config
1620 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1621 mrproper-dirs := $(addprefix _mrproper_,scripts)
1623 PHONY += $(mrproper-dirs) mrproper
1625 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1627 mrproper: clean $(mrproper-dirs)
1629 @find . $(RCS_FIND_IGNORE) \
1630 \( -name '*.rmeta' \) \
1631 -type f -print | xargs rm -f
1638 @find . $(RCS_FIND_IGNORE) \
1639 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1640 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1641 -o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1642 -o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1643 -type f -print | xargs rm -f
1646 # Packaging of the kernel to various formats
1647 # ---------------------------------------------------------------------------
1650 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1651 %pkg: include/config/kernel.release FORCE
1652 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1654 # Brief documentation of the typical targets used
1655 # ---------------------------------------------------------------------------
1657 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1658 boards := $(sort $(notdir $(boards)))
1659 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1660 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1664 @echo 'Cleaning targets:'
1665 @echo ' clean - Remove most generated files but keep the config and'
1666 @echo ' enough build support to build external modules'
1667 @echo ' mrproper - Remove all generated files + config + various backup files'
1668 @echo ' distclean - mrproper + remove editor backup and patch files'
1670 @echo 'Configuration targets:'
1671 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1673 @echo 'Other generic targets:'
1674 @echo ' all - Build all targets marked with [*]'
1675 @echo '* vmlinux - Build the bare kernel'
1676 @echo '* modules - Build all modules'
1677 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1678 @echo ' dir/ - Build all files in dir and below'
1679 @echo ' dir/file.[ois] - Build specified target only'
1680 @echo ' dir/file.ll - Build the LLVM assembly file'
1681 @echo ' (requires compiler support for LLVM assembly generation)'
1682 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1683 @echo ' (requires a recent binutils and recent build (System.map))'
1684 @echo ' dir/file.ko - Build module including final link'
1685 @echo ' modules_prepare - Set up for building external modules'
1686 @echo ' tags/TAGS - Generate tags file for editors'
1687 @echo ' cscope - Generate cscope index'
1688 @echo ' gtags - Generate GNU GLOBAL index'
1689 @echo ' kernelrelease - Output the release version string (use with make -s)'
1690 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1691 @echo ' image_name - Output the image name (use with make -s)'
1692 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1693 echo ' (default: $(INSTALL_HDR_PATH))'; \
1695 @echo 'Static analysers:'
1696 @echo ' checkstack - Generate a list of stack hogs'
1697 @echo ' versioncheck - Sanity check on version.h usage'
1698 @echo ' includecheck - Check for duplicate included header files'
1699 @echo ' export_report - List the usages of all exported symbols'
1700 @echo ' headerdep - Detect inclusion cycles in headers'
1701 @echo ' coccicheck - Check with Coccinelle'
1702 @echo ' clang-analyzer - Check with clang static analyzer'
1703 @echo ' clang-tidy - Check with clang-tidy'
1706 @echo ' nsdeps - Generate missing symbol namespace dependencies'
1708 @echo 'Kernel selftest:'
1709 @echo ' kselftest - Build and run kernel selftest'
1710 @echo ' Build, install, and boot kernel before'
1711 @echo ' running kselftest on it'
1712 @echo ' Run as root for full coverage'
1713 @echo ' kselftest-all - Build kernel selftest'
1714 @echo ' kselftest-install - Build and install kernel selftest'
1715 @echo ' kselftest-clean - Remove all generated kselftest files'
1716 @echo ' kselftest-merge - Merge all the config dependencies of'
1717 @echo ' kselftest to existing .config.'
1719 @echo 'Rust targets:'
1720 @echo ' rustavailable - Checks whether the Rust toolchain is'
1721 @echo ' available and, if not, explains why.'
1722 @echo ' rustfmt - Reformat all the Rust code in the kernel'
1723 @echo ' rustfmtcheck - Checks if all the Rust code in the kernel'
1724 @echo ' is formatted, printing a diff otherwise.'
1725 @echo ' rustdoc - Generate Rust documentation'
1726 @echo ' (requires kernel .config)'
1727 @echo ' rusttest - Runs the Rust tests'
1728 @echo ' (requires kernel .config; downloads external repos)'
1729 @echo ' rust-analyzer - Generate rust-project.json rust-analyzer support file'
1730 @echo ' (requires kernel .config)'
1731 @echo ' dir/file.[os] - Build specified target only'
1732 @echo ' dir/file.rsi - Build macro expanded source, similar to C preprocessing.'
1733 @echo ' Run with RUSTFMT=n to skip reformatting if needed.'
1734 @echo ' The output is not intended to be compilable.'
1735 @echo ' dir/file.ll - Build the LLVM assembly file'
1738 echo 'Devicetree:'; \
1739 echo '* dtbs - Build device tree blobs for enabled boards'; \
1740 echo ' dtbs_install - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1741 echo ' dt_binding_check - Validate device tree binding documents'; \
1742 echo ' dtbs_check - Validate device tree source files';\
1745 @echo 'Userspace tools targets:'
1746 @echo ' use "make tools/help"'
1747 @echo ' or "cd tools; make help"'
1749 @echo 'Kernel packaging:'
1750 @$(MAKE) -f $(srctree)/scripts/Makefile.package help
1752 @echo 'Documentation targets:'
1753 @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1755 @echo 'Architecture specific targets ($(SRCARCH)):'
1757 echo ' No architecture specific help defined for $(SRCARCH)')
1760 $(foreach b, $(boards), \
1761 printf " %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1763 @$(if $(board-dirs), \
1764 $(foreach b, $(board-dirs), \
1765 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1766 printf " %-16s - Show all of the above\\n" help-boards; \
1769 @echo ' make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1770 @echo ' make V=2 [targets] 2 => give reason for rebuild of target'
1771 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1772 @echo ' make C=1 [targets] Check re-compiled c source with $$CHECK'
1773 @echo ' (sparse by default)'
1774 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1775 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1776 @echo ' make W=n [targets] Enable extra build checks, n=1,2,3 where'
1777 @echo ' 1: warnings which may be relevant and do not occur too often'
1778 @echo ' 2: warnings which occur quite often but may still be relevant'
1779 @echo ' 3: more obscure warnings, can most likely be ignored'
1780 @echo ' e: warnings are being treated as errors'
1781 @echo ' Multiple levels can be combined with W=12 or W=123'
1783 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1784 @echo 'For further info see the ./README file'
1787 help-board-dirs := $(addprefix help-,$(board-dirs))
1789 help-boards: $(help-board-dirs)
1791 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1793 $(help-board-dirs): help-%:
1794 @echo 'Architecture specific targets ($(SRCARCH) $*):'
1795 @$(if $(boards-per-dir), \
1796 $(foreach b, $(boards-per-dir), \
1797 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1801 # Documentation targets
1802 # ---------------------------------------------------------------------------
1803 DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1804 linkcheckdocs dochelp refcheckdocs
1805 PHONY += $(DOC_TARGETS)
1807 $(Q)$(MAKE) $(build)=Documentation $@
1811 # ---------------------------------------------------------------------------
1813 # "Is Rust available?" target
1814 PHONY += rustavailable
1816 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh && echo "Rust is available!"
1818 # Documentation target
1820 # Using the singular to avoid running afoul of `no-dot-config-targets`.
1823 $(Q)$(MAKE) $(build)=rust $@
1828 $(Q)$(MAKE) $(build)=rust $@
1830 # Formatting targets
1831 PHONY += rustfmt rustfmtcheck
1833 # We skip `rust/alloc` since we want to minimize the diff w.r.t. upstream.
1835 # We match using absolute paths since `find` does not resolve them
1836 # when matching, which is a problem when e.g. `srctree` is `..`.
1837 # We `grep` afterwards in order to remove the directory entry itself.
1839 $(Q)find $(abs_srctree) -type f -name '*.rs' \
1840 -o -path $(abs_srctree)/rust/alloc -prune \
1841 -o -path $(abs_objtree)/rust/test -prune \
1842 | grep -Fv $(abs_srctree)/rust/alloc \
1843 | grep -Fv $(abs_objtree)/rust/test \
1844 | grep -Fv generated \
1845 | xargs $(RUSTFMT) $(rustfmt_flags)
1847 rustfmtcheck: rustfmt_flags = --check
1848 rustfmtcheck: rustfmt
1850 # IDE support targets
1851 PHONY += rust-analyzer
1853 $(Q)$(MAKE) $(build)=rust $@
1856 # ---------------------------------------------------------------------------
1858 PHONY += scripts_gdb
1859 scripts_gdb: prepare0
1860 $(Q)$(MAKE) $(build)=scripts/gdb
1861 $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1863 ifdef CONFIG_GDB_SCRIPTS
1867 else # KBUILD_EXTMOD
1870 # External module support.
1871 # When building external modules the kernel used as basis is considered
1872 # read-only, and no consistency checks are made and the make
1873 # system is not used on the basis kernel. If updates are required
1874 # in the basis kernel ordinary make commands (without M=...) must be used.
1876 # We are always building only modules.
1880 build-dir := $(KBUILD_EXTMOD)
1882 compile_commands.json: $(extmod_prefix)compile_commands.json
1883 PHONY += compile_commands.json
1885 clean-dirs := $(KBUILD_EXTMOD)
1886 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1887 $(KBUILD_EXTMOD)/compile_commands.json $(KBUILD_EXTMOD)/.thinlto-cache
1890 # now expand this into a simple variable to reduce the cost of shell evaluations
1891 prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT)
1893 @if [ "$(CC_VERSION_TEXT)" != "$(CONFIG_CC_VERSION_TEXT)" ]; then \
1894 echo >&2 "warning: the compiler differs from the one used to build the kernel"; \
1895 echo >&2 " The kernel was built by: $(CONFIG_CC_VERSION_TEXT)"; \
1896 echo >&2 " You are using: $(CC_VERSION_TEXT)"; \
1901 @echo ' Building external modules.'
1902 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1904 @echo ' modules - default target, build the module(s)'
1905 @echo ' modules_install - install the module'
1906 @echo ' clean - remove generated files in module directory only'
1909 endif # KBUILD_EXTMOD
1911 # ---------------------------------------------------------------------------
1914 PHONY += modules modules_install modules_prepare
1916 ifdef CONFIG_MODULES
1918 $(MODORDER): $(build-dir)
1921 # KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
1922 # This is solely useful to speed up test compiles.
1924 ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1925 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1928 PHONY += modules_check
1929 modules_check: $(MODORDER)
1930 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1932 quiet_cmd_depmod = DEPMOD $(MODLIB)
1933 cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1937 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1938 ifndef modules_sign_only
1942 else # CONFIG_MODULES
1944 # Modules not configured
1945 # ---------------------------------------------------------------------------
1947 modules modules_install:
1949 @echo >&2 '*** The present kernel configuration has modules disabled.'
1950 @echo >&2 '*** To use the module feature, please run "make menuconfig" etc.'
1951 @echo >&2 '*** to enable CONFIG_MODULES.'
1957 endif # CONFIG_MODULES
1960 modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \
1961 $(if $(KBUILD_MODULES), modules_check)
1962 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1965 # ---------------------------------------------------------------------------
1966 # To build individual files in subdirectories, you can do like this:
1968 # make foo/bar/baz.s
1970 # The supported suffixes for single-target are listed in 'single-targets'
1972 # To build only under specific subdirectories, you can do like this:
1978 # .ko is special because modpost is needed
1979 single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1980 single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \
1981 $(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko)))
1983 $(single-ko): single_modules
1985 $(single-no-ko): $(build-dir)
1988 # Remove MODORDER when done because it is not the real one.
1989 PHONY += single_modules
1990 single_modules: $(single-no-ko) modules_prepare
1991 $(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$m;) } > $(MODORDER)
1992 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1993 ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1994 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1996 $(Q)rm -f $(MODORDER)
1998 single-goals := $(addprefix $(build-dir)/, $(single-no-ko))
2004 # Preset locale variables to speed up the build process. Limit locale
2005 # tweaks to this spot to avoid wrong language settings when running
2006 # make menuconfig etc.
2007 # Error messages still appears in the original language
2008 PHONY += $(build-dir)
2009 $(build-dir): prepare
2010 $(Q)$(MAKE) $(build)=$@ need-builtin=1 need-modorder=1 $(single-goals)
2012 clean-dirs := $(addprefix _clean_, $(clean-dirs))
2013 PHONY += $(clean-dirs) clean
2015 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
2017 clean: $(clean-dirs)
2019 @find $(or $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
2020 \( -name '*.[aios]' -o -name '*.rsi' -o -name '*.ko' -o -name '.*.cmd' \
2022 -o -name '*.dtb' -o -name '*.dtbo' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
2023 -o -name '*.dwo' -o -name '*.lst' \
2024 -o -name '*.su' -o -name '*.mod' -o -name '*.usyms' \
2025 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
2026 -o -name '*.lex.c' -o -name '*.tab.[ch]' \
2027 -o -name '*.asn1.[ch]' \
2028 -o -name '*.symtypes' -o -name 'modules.order' \
2030 -o -name '*.c.[012]*.*' \
2033 -o -name '*.*.symversions' \) -type f -print | xargs rm -f
2035 # Generate tags for editors
2036 # ---------------------------------------------------------------------------
2037 quiet_cmd_tags = GEN $@
2038 cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
2040 tags TAGS cscope gtags: FORCE
2043 # Script to generate missing namespace dependencies
2044 # ---------------------------------------------------------------------------
2047 nsdeps: export KBUILD_NSDEPS=1
2049 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
2052 # ---------------------------------------------------------------------------
2054 quiet_cmd_gen_compile_commands = GEN $@
2055 cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
2057 $(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
2058 $(if $(KBUILD_EXTMOD),, vmlinux.a $(KBUILD_VMLINUX_LIBS)) \
2059 $(if $(CONFIG_MODULES), $(MODORDER)) FORCE
2060 $(call if_changed,gen_compile_commands)
2062 targets += $(extmod_prefix)compile_commands.json
2064 PHONY += clang-tidy clang-analyzer
2066 ifdef CONFIG_CC_IS_CLANG
2067 quiet_cmd_clang_tools = CHECK $<
2068 cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
2070 clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
2071 $(call cmd,clang_tools)
2073 clang-tidy clang-analyzer:
2074 @echo "$@ requires CC=clang" >&2
2078 # Scripts to check various things for consistency
2079 # ---------------------------------------------------------------------------
2081 PHONY += includecheck versioncheck coccicheck export_report
2084 find $(srctree)/* $(RCS_FIND_IGNORE) \
2085 -name '*.[hcS]' -type f -print | sort \
2086 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
2089 find $(srctree)/* $(RCS_FIND_IGNORE) \
2090 -name '*.[hcS]' -type f -print | sort \
2091 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
2094 $(Q)$(BASH) $(srctree)/scripts/$@
2097 $(PERL) $(srctree)/scripts/export_report.pl
2099 PHONY += checkstack kernelrelease kernelversion image_name
2101 # UML needs a little special treatment here. It wants to use the host
2102 # toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
2103 # else wants $(ARCH), including people doing cross-builds, which means
2104 # that $(SUBARCH) doesn't work here.
2106 CHECKSTACK_ARCH := $(SUBARCH)
2108 CHECKSTACK_ARCH := $(ARCH)
2111 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
2112 $(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
2115 @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
2118 @echo $(KERNELVERSION)
2121 @echo $(KBUILD_IMAGE)
2123 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
2124 cmd_rmfiles = rm -rf $(rm-files)
2126 # read saved command lines for existing targets
2127 existing-targets := $(wildcard $(sort $(targets)))
2129 -include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
2131 endif # config-build
2133 endif # need-sub-make
2138 # Declare the contents of the PHONY variable as phony. We keep that
2139 # information in a variable so we can use it in if_changed and friends.