1 # SPDX-License-Identifier: GPL-2.0
6 NAME = Kleptomaniac Octopus
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 # That's our default target when none is given on the command line
18 # We are using a recursive build, so we need to do a little thinking
19 # to get the ordering right.
21 # Most importantly: sub-Makefiles should only ever modify files in
22 # their own directory. If in some directory we have a dependency on
23 # a file in another dir (which doesn't happen often, but it's often
24 # unavoidable when linking the built-in.a targets which finally
25 # turn into vmlinux), we will call a sub make in that other dir, and
26 # after that we are sure that everything which is in that other dir
29 # The only cases where we need to modify files which have global
30 # effects are thus separated out and done before the recursive
31 # descending is started. They are now explicitly listed as the
34 ifneq ($(sub_make_done),1)
36 # Do not use make's built-in rules and variables
37 # (this increases performance and avoids hard-to-debug behaviour)
40 # Avoid funny character set dependencies
44 export LC_COLLATE LC_NUMERIC
46 # Avoid interference with shell env settings
50 # ---------------------------------------------------------------------------
52 # Normally, we echo the whole command before executing it. By making
53 # that echo $($(quiet)$(cmd)), we now have the possibility to set
54 # $(quiet) to choose other forms of output instead, e.g.
56 # quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
57 # cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
59 # If $(quiet) is empty, the whole command will be printed.
60 # If it is set to "quiet_", only the short version will be printed.
61 # If it is set to "silent_", nothing will be printed at all, since
62 # the variable $(silent_cmd_cc_o_c) doesn't exist.
64 # A simple variant is to prefix commands with $(Q) - that's useful
65 # for commands that shall be hidden in non-verbose mode.
69 # If KBUILD_VERBOSE equals 0 then the above command will be hidden.
70 # If KBUILD_VERBOSE equals 1 then the above command is displayed.
72 # To put more focus on warnings, be less verbose as default
73 # Use 'make V=1' to see the full commands
75 ifeq ("$(origin V)", "command line")
82 ifeq ($(KBUILD_VERBOSE),1)
90 # If the user is running make -s (silent mode), suppress echoing of
93 ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
97 export quiet Q KBUILD_VERBOSE
99 # Kbuild will save output files in the current working directory.
100 # This does not need to match to the root of the kernel source tree.
102 # For example, you can do this:
104 # cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
106 # If you want to save output files in a different location, there are
107 # two syntaxes to specify it.
110 # Use "make O=dir/to/store/output/files/"
112 # 2) Set KBUILD_OUTPUT
113 # Set the environment variable KBUILD_OUTPUT to point to the output directory.
114 # export KBUILD_OUTPUT=dir/to/store/output/files/; make
116 # The O= assignment takes precedence over the KBUILD_OUTPUT environment
119 # Do we want to change the working directory?
120 ifeq ("$(origin O)", "command line")
121 KBUILD_OUTPUT := $(O)
124 ifneq ($(KBUILD_OUTPUT),)
125 # Make's built-in functions such as $(abspath ...), $(realpath ...) cannot
126 # expand a shell special character '~'. We use a somewhat tedious way here.
127 abs_objtree := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) && pwd)
128 $(if $(abs_objtree),, \
129 $(error failed to create output directory "$(KBUILD_OUTPUT)"))
131 # $(realpath ...) resolves symlinks
132 abs_objtree := $(realpath $(abs_objtree))
134 abs_objtree := $(CURDIR)
135 endif # ifneq ($(KBUILD_OUTPUT),)
137 ifeq ($(abs_objtree),$(CURDIR))
138 # Suppress "Entering directory ..." unless we are changing the work directory.
139 MAKEFLAGS += --no-print-directory
144 abs_srctree := $(realpath $(dir $(lastword $(MAKEFILE_LIST))))
146 ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
147 $(error source directory cannot contain spaces or colons)
150 ifneq ($(abs_srctree),$(abs_objtree))
151 # Look for make include files relative to root of kernel src
153 # This does not become effective immediately because MAKEFLAGS is re-parsed
154 # once after the Makefile is read. We need to invoke sub-make.
155 MAKEFLAGS += --include-dir=$(abs_srctree)
159 ifneq ($(filter 3.%,$(MAKE_VERSION)),)
160 # 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
161 # We need to invoke sub-make to avoid implicit rules in the top Makefile.
163 # Cancel implicit rules for this Makefile.
164 $(lastword $(MAKEFILE_LIST)): ;
167 export abs_srctree abs_objtree
168 export sub_make_done := 1
170 ifeq ($(need-sub-make),1)
172 PHONY += $(MAKECMDGOALS) sub-make
174 $(filter-out _all sub-make $(lastword $(MAKEFILE_LIST)), $(MAKECMDGOALS)) _all: sub-make
177 # Invoke a second make in the output directory, passing relevant variables
179 $(Q)$(MAKE) -C $(abs_objtree) -f $(abs_srctree)/Makefile $(MAKECMDGOALS)
181 endif # need-sub-make
182 endif # sub_make_done
184 # We process the rest of the Makefile if this is the final invocation of make
185 ifeq ($(need-sub-make),)
187 # Do not print "Entering directory ...",
188 # but we want to display it when entering to the output directory
189 # so that IDEs/editors are able to understand relative filenames.
190 MAKEFLAGS += --no-print-directory
192 # Call a source code checker (by default, "sparse") as part of the
195 # Use 'make C=1' to enable checking of only re-compiled files.
196 # Use 'make C=2' to enable checking of *all* source files, regardless
197 # of whether they are re-compiled or not.
199 # See the file "Documentation/dev-tools/sparse.rst" for more details,
200 # including where to get the "sparse" utility.
202 ifeq ("$(origin C)", "command line")
203 KBUILD_CHECKSRC = $(C)
205 ifndef KBUILD_CHECKSRC
209 # Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
210 # directory of external module to build. Setting M= takes precedence.
211 ifeq ("$(origin M)", "command line")
212 KBUILD_EXTMOD := $(M)
215 export KBUILD_CHECKSRC KBUILD_EXTMOD
217 extmod-prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
219 ifeq ($(abs_srctree),$(abs_objtree))
220 # building in the source tree
222 building_out_of_srctree :=
224 ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
225 # building in a subdirectory of the source tree
228 srctree := $(abs_srctree)
230 building_out_of_srctree := 1
233 ifneq ($(KBUILD_ABS_SRCTREE),)
234 srctree := $(abs_srctree)
240 export building_out_of_srctree srctree objtree VPATH
242 # To make sure we do not include .config for any of the *config targets
243 # catch them early, and hand them over to scripts/kconfig/Makefile
244 # It is allowed to specify more targets when calling make, including
245 # mixing *config targets and build targets.
246 # For example 'make oldconfig all'.
247 # Detect when mixed targets is specified, and make a second invocation
248 # of make so .config is not included in this case either (for *config).
250 version_h := include/generated/uapi/linux/version.h
251 old_version_h := include/linux/version.h
253 clean-targets := %clean mrproper cleandocs
254 no-dot-config-targets := $(clean-targets) \
255 cscope gtags TAGS tags help% %docs check% coccicheck \
256 $(version_h) headers headers_% archheaders archscripts \
257 %asm-generic kernelversion %src-pkg
258 no-sync-config-targets := $(no-dot-config-targets) install %install \
260 single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
268 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
269 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
274 ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
275 ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
280 ifneq ($(KBUILD_EXTMOD),)
284 ifeq ($(KBUILD_EXTMOD),)
285 ifneq ($(filter config %config,$(MAKECMDGOALS)),)
287 ifneq ($(words $(MAKECMDGOALS)),1)
293 # We cannot build single targets and the others at the same time
294 ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
296 ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
301 # For "make -j clean all", "make -j mrproper defconfig all", etc.
302 ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
303 ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
308 # install and modules_install need also be processed one by one
309 ifneq ($(filter install,$(MAKECMDGOALS)),)
310 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
316 # ===========================================================================
317 # We're called with mixed targets (*config and build targets).
318 # Handle them one by one.
320 PHONY += $(MAKECMDGOALS) __build_one_by_one
322 $(filter-out __build_one_by_one, $(MAKECMDGOALS)): __build_one_by_one
327 for i in $(MAKECMDGOALS); do \
328 $(MAKE) -f $(srctree)/Makefile $$i; \
333 include scripts/Kbuild.include
335 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
336 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
337 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
338 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
340 include scripts/subarch.include
342 # Cross compiling and selecting different set of gcc/bin-utils
343 # ---------------------------------------------------------------------------
345 # When performing cross compilation for other architectures ARCH shall be set
346 # to the target architecture. (See arch/* for the possibilities).
347 # ARCH can be set during invocation of make:
349 # Another way is to have ARCH set in the environment.
350 # The default ARCH is the host where make is executed.
352 # CROSS_COMPILE specify the prefix used for all executables used
353 # during compilation. Only gcc and related bin-utils executables
354 # are prefixed with $(CROSS_COMPILE).
355 # CROSS_COMPILE can be set on the command line
356 # make CROSS_COMPILE=ia64-linux-
357 # Alternatively CROSS_COMPILE can be set in the environment.
358 # Default value for CROSS_COMPILE is not to prefix executables
359 # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
362 # Architecture as present in compile.h
363 UTS_MACHINE := $(ARCH)
366 # Additional ARCH settings for x86
370 ifeq ($(ARCH),x86_64)
374 # Additional ARCH settings for sparc
375 ifeq ($(ARCH),sparc32)
378 ifeq ($(ARCH),sparc64)
382 # Additional ARCH settings for sh
387 KCONFIG_CONFIG ?= .config
388 export KCONFIG_CONFIG
390 # SHELL used by kbuild
393 HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
394 HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
395 HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
404 KBUILD_HOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 \
405 -fomit-frame-pointer -std=gnu89 $(HOST_LFS_CFLAGS) \
407 KBUILD_HOSTCXXFLAGS := -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
408 KBUILD_HOSTLDFLAGS := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
409 KBUILD_HOSTLDLIBS := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
411 # Make variables (CC, etc...)
418 OBJCOPY = llvm-objcopy
419 OBJDUMP = llvm-objdump
420 READELF = llvm-readelf
424 CC = $(CROSS_COMPILE)gcc
425 LD = $(CROSS_COMPILE)ld
426 AR = $(CROSS_COMPILE)ar
427 NM = $(CROSS_COMPILE)nm
428 OBJCOPY = $(CROSS_COMPILE)objcopy
429 OBJDUMP = $(CROSS_COMPILE)objdump
430 READELF = $(CROSS_COMPILE)readelf
431 OBJSIZE = $(CROSS_COMPILE)size
432 STRIP = $(CROSS_COMPILE)strip
438 INSTALLKERNEL := installkernel
452 CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
453 -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
462 # Use USERINCLUDE when you must reference the UAPI directories only.
464 -I$(srctree)/arch/$(SRCARCH)/include/uapi \
465 -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
466 -I$(srctree)/include/uapi \
467 -I$(objtree)/include/generated/uapi \
468 -include $(srctree)/include/linux/kconfig.h
470 # Use LINUXINCLUDE when you must reference the include/ directory.
471 # Needed to be compatible with the O= option
473 -I$(srctree)/arch/$(SRCARCH)/include \
474 -I$(objtree)/arch/$(SRCARCH)/include/generated \
475 $(if $(building_out_of_srctree),-I$(srctree)/include) \
476 -I$(objtree)/include \
479 KBUILD_AFLAGS := -D__ASSEMBLY__ -fno-PIE
480 KBUILD_CFLAGS := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
481 -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
482 -Werror=implicit-function-declaration -Werror=implicit-int \
483 -Werror=return-type -Wno-format-security \
485 KBUILD_CPPFLAGS := -D__KERNEL__
486 KBUILD_AFLAGS_KERNEL :=
487 KBUILD_CFLAGS_KERNEL :=
488 KBUILD_AFLAGS_MODULE := -DMODULE
489 KBUILD_CFLAGS_MODULE := -DMODULE
490 KBUILD_LDFLAGS_MODULE :=
491 export KBUILD_LDS_MODULE := $(srctree)/scripts/module-common.lds
493 GCC_PLUGINS_CFLAGS :=
496 export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC
497 export CPP AR NM STRIP OBJCOPY OBJDUMP OBJSIZE READELF PAHOLE LEX YACC AWK INSTALLKERNEL
498 export PERL PYTHON PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
499 export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ
500 export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
502 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
503 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
504 export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN
505 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
506 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
507 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
509 # Files to ignore in find ... statements
511 export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o \
512 -name CVS -o -name .pc -o -name .hg -o -name .git \) \
514 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
515 --exclude CVS --exclude .pc --exclude .hg --exclude .git
517 # ===========================================================================
518 # Rules shared between *config targets and build targets
520 # Basic helpers built in scripts/basic/
521 PHONY += scripts_basic
523 $(Q)$(MAKE) $(build)=scripts/basic
524 $(Q)rm -f .tmp_quiet_recordmcount
526 PHONY += outputmakefile
527 # Before starting out-of-tree build, make sure the source tree is clean.
528 # outputmakefile generates a Makefile in the output directory, if using a
529 # separate output directory. This allows convenient use of make in the
531 # At the same time when output Makefile generated, generate .gitignore to
532 # ignore whole output directory
534 ifdef building_out_of_srctree
535 $(Q)if [ -f $(srctree)/.config -o \
536 -d $(srctree)/include/config -o \
537 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
539 echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
540 echo >&2 "*** in $(abs_srctree)";\
544 $(Q)ln -fsn $(srctree) source
545 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile $(srctree)
546 $(Q)test -e .gitignore || \
547 { echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
550 ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),)
551 ifneq ($(CROSS_COMPILE),)
552 CLANG_FLAGS += --target=$(notdir $(CROSS_COMPILE:%-=%))
553 GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
554 CLANG_FLAGS += --prefix=$(GCC_TOOLCHAIN_DIR)$(notdir $(CROSS_COMPILE))
555 GCC_TOOLCHAIN := $(realpath $(GCC_TOOLCHAIN_DIR)/..)
557 ifneq ($(GCC_TOOLCHAIN),)
558 CLANG_FLAGS += --gcc-toolchain=$(GCC_TOOLCHAIN)
560 ifneq ($(LLVM_IAS),1)
561 CLANG_FLAGS += -no-integrated-as
563 CLANG_FLAGS += -Werror=unknown-warning-option
564 KBUILD_CFLAGS += $(CLANG_FLAGS)
565 KBUILD_AFLAGS += $(CLANG_FLAGS)
569 # The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
570 # Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
571 # CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
572 # and from include/config/auto.conf.cmd to detect the compiler upgrade.
573 CC_VERSION_TEXT = $(shell $(CC) --version 2>/dev/null | head -n 1)
576 # ===========================================================================
577 # *config targets only - make sure prerequisites are updated, and descend
578 # in scripts/kconfig to make the *config target
580 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
581 # KBUILD_DEFCONFIG may point out an alternative default configuration
582 # used for 'make defconfig'
583 include arch/$(SRCARCH)/Makefile
584 export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
586 config: outputmakefile scripts_basic FORCE
587 $(Q)$(MAKE) $(build)=scripts/kconfig $@
589 %config: outputmakefile scripts_basic FORCE
590 $(Q)$(MAKE) $(build)=scripts/kconfig $@
593 # ===========================================================================
594 # Build targets only - this includes vmlinux, arch specific targets, clean
595 # targets and others. In general all targets except *config targets.
597 # If building an external module we do not care about the all: rule
598 # but instead _all depend on modules
600 ifeq ($(KBUILD_EXTMOD),)
606 # Decide whether to build built-in, modular, or both.
607 # Normally, just do built-in.
612 # If we have only "make modules", don't compile built-in objects.
613 ifeq ($(MAKECMDGOALS),modules)
617 # If we have "make <whatever> modules", compile modules
618 # in addition to whatever we do anyway.
619 # Just "make" or "make all" shall build modules as well
621 ifneq ($(filter all _all modules nsdeps,$(MAKECMDGOALS)),)
625 ifeq ($(MAKECMDGOALS),)
629 export KBUILD_MODULES KBUILD_BUILTIN
632 include include/config/auto.conf
635 ifeq ($(KBUILD_EXTMOD),)
636 # Objects we will link into vmlinux / subdirs we need to visit
638 drivers-y := drivers/ sound/
639 drivers-$(CONFIG_SAMPLES) += samples/
644 endif # KBUILD_EXTMOD
646 # The all: target is the default when no target is given on the
648 # This allow a user to issue only 'make' to build a kernel including modules
649 # Defaults to vmlinux, but the arch makefile usually adds further targets
652 CFLAGS_GCOV := -fprofile-arcs -ftest-coverage \
653 $(call cc-option,-fno-tree-loop-im) \
654 $(call cc-disable-warning,maybe-uninitialized,)
657 # The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
658 ifdef CONFIG_FUNCTION_TRACER
659 CC_FLAGS_FTRACE := -pg
662 RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
663 RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
664 RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
665 RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
666 RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
667 RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
668 export RETPOLINE_CFLAGS
669 export RETPOLINE_VDSO_CFLAGS
671 include arch/$(SRCARCH)/Makefile
674 ifdef may-sync-config
675 # Read in dependencies to all Kconfig* files, make sure to run syncconfig if
676 # changes are detected. This should be included after arch/$(SRCARCH)/Makefile
677 # because some architectures define CROSS_COMPILE there.
678 include include/config/auto.conf.cmd
682 @echo >&2 '*** Configuration file "$@" not found!'
684 @echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
685 @echo >&2 '*** "make menuconfig" or "make xconfig").'
689 # The actual configuration files used during the build are stored in
690 # include/generated/ and include/config/. Update them if .config is newer than
691 # include/config/auto.conf (which mirrors .config).
693 # This exploits the 'multi-target pattern rule' trick.
694 # The syncconfig should be executed only once to make all the targets.
695 %/auto.conf %/auto.conf.cmd %/tristate.conf: $(KCONFIG_CONFIG)
696 $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
697 else # !may-sync-config
698 # External modules and some install targets need include/generated/autoconf.h
699 # and include/config/auto.conf but do not care if they are up-to-date.
700 # Use auto.conf to trigger the test
701 PHONY += include/config/auto.conf
703 include/config/auto.conf:
704 $(Q)test -e include/generated/autoconf.h -a -e $@ || ( \
706 echo >&2 " ERROR: Kernel configuration is invalid."; \
707 echo >&2 " include/generated/autoconf.h or $@ are missing.";\
708 echo >&2 " Run 'make oldconfig && make prepare' on kernel src to fix it."; \
712 endif # may-sync-config
715 KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,)
716 KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,)
717 KBUILD_CFLAGS += $(call cc-disable-warning, format-truncation)
718 KBUILD_CFLAGS += $(call cc-disable-warning, format-overflow)
719 KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
721 ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
723 else ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3
725 else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
729 # Tell gcc to never replace conditional load with a non-conditional one
730 KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
731 KBUILD_CFLAGS += $(call cc-option,-fno-allow-store-data-races)
733 include scripts/Makefile.kcov
734 include scripts/Makefile.gcc-plugins
736 ifdef CONFIG_READABLE_ASM
737 # Disable optimizations that make assembler listings hard to read.
738 # reorder blocks reorders the control in the function
739 # ipa clone creates specialized cloned functions
740 # partial inlining inlines only parts of functions
741 KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
742 $(call cc-option,-fno-ipa-cp-clone,) \
743 $(call cc-option,-fno-partial-inlining)
746 ifneq ($(CONFIG_FRAME_WARN),0)
747 KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
750 stackp-flags-$(CONFIG_CC_HAS_STACKPROTECTOR_NONE) := -fno-stack-protector
751 stackp-flags-$(CONFIG_STACKPROTECTOR) := -fstack-protector
752 stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG) := -fstack-protector-strong
754 KBUILD_CFLAGS += $(stackp-flags-y)
756 ifdef CONFIG_CC_IS_CLANG
757 KBUILD_CPPFLAGS += -Qunused-arguments
758 KBUILD_CFLAGS += -Wno-format-invalid-specifier
759 KBUILD_CFLAGS += -Wno-gnu
760 # Quiet clang warning: comparison of unsigned expression < 0 is always false
761 KBUILD_CFLAGS += -Wno-tautological-compare
762 # CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
763 # source of a reference will be _MergedGlobals and not on of the whitelisted names.
764 # See modpost pattern 2
765 KBUILD_CFLAGS += -mno-global-merge
768 # Warn about unmarked fall-throughs in switch statement.
769 # Disabled for clang while comment to attribute conversion happens and
770 # https://github.com/ClangBuiltLinux/linux/issues/636 is discussed.
771 KBUILD_CFLAGS += $(call cc-option,-Wimplicit-fallthrough,)
774 # These warnings generated too much noise in a regular build.
775 # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
776 KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
778 KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
779 ifdef CONFIG_FRAME_POINTER
780 KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
782 # Some targets (ARM with Thumb2, for example), can't be built with frame
783 # pointers. For those, we don't have FUNCTION_TRACER automatically
784 # select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
785 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
786 # -fomit-frame-pointer with FUNCTION_TRACER.
787 ifndef CONFIG_FUNCTION_TRACER
788 KBUILD_CFLAGS += -fomit-frame-pointer
792 # Initialize all stack variables with a pattern, if desired.
793 ifdef CONFIG_INIT_STACK_ALL
794 KBUILD_CFLAGS += -ftrivial-auto-var-init=pattern
797 DEBUG_CFLAGS := $(call cc-option, -fno-var-tracking-assignments)
799 ifdef CONFIG_DEBUG_INFO
800 ifdef CONFIG_DEBUG_INFO_SPLIT
801 DEBUG_CFLAGS += -gsplit-dwarf
805 ifneq ($(LLVM_IAS),1)
806 KBUILD_AFLAGS += -Wa,-gdwarf-2
810 ifdef CONFIG_DEBUG_INFO_DWARF4
811 DEBUG_CFLAGS += -gdwarf-4
814 ifdef CONFIG_DEBUG_INFO_REDUCED
815 DEBUG_CFLAGS += $(call cc-option, -femit-struct-debug-baseonly) \
816 $(call cc-option,-fno-var-tracking)
819 KBUILD_CFLAGS += $(DEBUG_CFLAGS)
822 ifdef CONFIG_FUNCTION_TRACER
823 ifdef CONFIG_FTRACE_MCOUNT_RECORD
824 # gcc 5 supports generating the mcount tables directly
825 ifeq ($(call cc-option-yn,-mrecord-mcount),y)
826 CC_FLAGS_FTRACE += -mrecord-mcount
827 export CC_USING_RECORD_MCOUNT := 1
829 ifdef CONFIG_HAVE_NOP_MCOUNT
830 ifeq ($(call cc-option-yn, -mnop-mcount),y)
831 CC_FLAGS_FTRACE += -mnop-mcount
832 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
836 ifdef CONFIG_HAVE_FENTRY
837 ifeq ($(call cc-option-yn, -mfentry),y)
838 CC_FLAGS_FTRACE += -mfentry
839 CC_FLAGS_USING += -DCC_USING_FENTRY
842 export CC_FLAGS_FTRACE
843 KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
844 KBUILD_AFLAGS += $(CC_FLAGS_USING)
845 ifdef CONFIG_DYNAMIC_FTRACE
846 ifdef CONFIG_HAVE_C_RECORDMCOUNT
847 BUILD_C_RECORDMCOUNT := y
848 export BUILD_C_RECORDMCOUNT
853 # We trigger additional mismatches with less inlining
854 ifdef CONFIG_DEBUG_SECTION_MISMATCH
855 KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
858 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
859 KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
860 LDFLAGS_vmlinux += --gc-sections
863 ifdef CONFIG_LIVEPATCH
864 KBUILD_CFLAGS += $(call cc-option, -flive-patching=inline-clone)
867 # arch Makefile may override CC so keep this after arch Makefile is included
868 NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
870 # warn about C99 declaration after statement
871 KBUILD_CFLAGS += -Wdeclaration-after-statement
873 # Variable Length Arrays (VLAs) should not be used anywhere in the kernel
874 KBUILD_CFLAGS += -Wvla
876 # disable pointer signed / unsigned warnings in gcc 4.0
877 KBUILD_CFLAGS += -Wno-pointer-sign
879 # disable stringop warnings in gcc 8+
880 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
882 # We'll want to enable this eventually, but it's not going away for 5.7 at least
883 KBUILD_CFLAGS += $(call cc-disable-warning, zero-length-bounds)
884 KBUILD_CFLAGS += $(call cc-disable-warning, array-bounds)
885 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
887 # Another good warning that we'll want to enable eventually
888 KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
890 # Enabled with W=2, disabled by default as noisy
891 KBUILD_CFLAGS += $(call cc-disable-warning, maybe-uninitialized)
893 # disable invalid "can't wrap" optimizations for signed / pointers
894 KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow)
896 # clang sets -fmerge-all-constants by default as optimization, but this
897 # is non-conforming behavior for C and in fact breaks the kernel, so we
898 # need to disable it here generally.
899 KBUILD_CFLAGS += $(call cc-option,-fno-merge-all-constants)
901 # for gcc -fno-merge-all-constants disables everything, but it is fine
902 # to have actual conforming behavior enabled.
903 KBUILD_CFLAGS += $(call cc-option,-fmerge-constants)
905 # Make sure -fstack-check isn't enabled (like gentoo apparently did)
906 KBUILD_CFLAGS += $(call cc-option,-fno-stack-check,)
908 # conserve stack if available
909 KBUILD_CFLAGS += $(call cc-option,-fconserve-stack)
911 # Prohibit date/time macros, which would make the build non-deterministic
912 KBUILD_CFLAGS += $(call cc-option,-Werror=date-time)
914 # enforce correct pointer usage
915 KBUILD_CFLAGS += $(call cc-option,-Werror=incompatible-pointer-types)
917 # Require designated initializers for all marked structures
918 KBUILD_CFLAGS += $(call cc-option,-Werror=designated-init)
920 # change __FILE__ to the relative path from the srctree
921 KBUILD_CFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
923 include scripts/Makefile.kasan
924 include scripts/Makefile.extrawarn
925 include scripts/Makefile.ubsan
927 # Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
928 KBUILD_CPPFLAGS += $(KCPPFLAGS)
929 KBUILD_AFLAGS += $(KAFLAGS)
930 KBUILD_CFLAGS += $(KCFLAGS)
932 KBUILD_LDFLAGS_MODULE += --build-id
933 LDFLAGS_vmlinux += --build-id
935 KBUILD_LDFLAGS += -z noexecstack
936 KBUILD_LDFLAGS += $(call ld-option,--no-warn-rwx-segments)
938 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
939 LDFLAGS_vmlinux += $(call ld-option, -X,)
942 ifeq ($(CONFIG_RELR),y)
943 LDFLAGS_vmlinux += --pack-dyn-relocs=relr --use-android-relr-tags
946 # make the checker run with the right architecture
947 CHECKFLAGS += --arch=$(ARCH)
949 # insure the checker run with the right endianness
950 CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
952 # the checker needs the correct machine size
953 CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
955 # Default kernel image to build when no specific target is given.
956 # KBUILD_IMAGE may be overruled on the command line or
957 # set in the environment
958 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
960 export KBUILD_IMAGE ?= vmlinux
963 # INSTALL_PATH specifies where to place the updated kernel and system map
964 # images. Default is /boot, but you can set it to other values
965 export INSTALL_PATH ?= /boot
968 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
969 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
970 # an argument if needed. Otherwise it defaults to the kernel install path
972 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
975 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
976 # relocations required by build roots. This is not defined in the
977 # makefile but the argument can be passed to make if needed.
980 MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
984 # INSTALL_MOD_STRIP, if defined, will cause modules to be
985 # stripped after they are installed. If INSTALL_MOD_STRIP is '1', then
986 # the default option --strip-debug will be used. Otherwise,
987 # INSTALL_MOD_STRIP value will be used as the options to the strip command.
989 ifdef INSTALL_MOD_STRIP
990 ifeq ($(INSTALL_MOD_STRIP),1)
991 mod_strip_cmd = $(STRIP) --strip-debug
993 mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
994 endif # INSTALL_MOD_STRIP=1
997 endif # INSTALL_MOD_STRIP
1000 # CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
1001 # after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
1002 # or CONFIG_MODULE_COMPRESS_XZ.
1004 mod_compress_cmd = true
1005 ifdef CONFIG_MODULE_COMPRESS
1006 ifdef CONFIG_MODULE_COMPRESS_GZIP
1007 mod_compress_cmd = $(KGZIP) -n -f
1008 endif # CONFIG_MODULE_COMPRESS_GZIP
1009 ifdef CONFIG_MODULE_COMPRESS_XZ
1010 mod_compress_cmd = $(XZ) -f
1011 endif # CONFIG_MODULE_COMPRESS_XZ
1012 endif # CONFIG_MODULE_COMPRESS
1013 export mod_compress_cmd
1015 ifdef CONFIG_MODULE_SIG_ALL
1016 $(eval $(call config_filename,MODULE_SIG_KEY))
1018 mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
1024 HOST_LIBELF_LIBS = $(shell pkg-config libelf --libs 2>/dev/null || echo -lelf)
1026 ifdef CONFIG_STACK_VALIDATION
1027 has_libelf := $(call try-run,\
1028 echo "int main() {}" | $(HOSTCC) $(KBUILD_HOSTLDFLAGS) -xc -o /dev/null $(HOST_LIBELF_LIBS) -,1,0)
1029 ifeq ($(has_libelf),1)
1030 objtool_target := tools/objtool FORCE
1032 SKIP_STACK_VALIDATION := 1
1033 export SKIP_STACK_VALIDATION
1039 export MODORDER := $(extmod-prefix)modules.order
1041 ifeq ($(KBUILD_EXTMOD),)
1042 core-y += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
1044 vmlinux-dirs := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
1045 $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
1046 $(net-y) $(net-m) $(libs-y) $(libs-m) $(virt-y)))
1048 vmlinux-alldirs := $(sort $(vmlinux-dirs) Documentation \
1049 $(patsubst %/,%,$(filter %/, $(init-) $(core-) \
1050 $(drivers-) $(net-) $(libs-) $(virt-))))
1052 build-dirs := $(vmlinux-dirs)
1053 clean-dirs := $(vmlinux-alldirs)
1055 init-y := $(patsubst %/, %/built-in.a, $(init-y))
1056 core-y := $(patsubst %/, %/built-in.a, $(core-y))
1057 drivers-y := $(patsubst %/, %/built-in.a, $(drivers-y))
1058 net-y := $(patsubst %/, %/built-in.a, $(net-y))
1059 libs-y1 := $(patsubst %/, %/lib.a, $(libs-y))
1060 libs-y2 := $(patsubst %/, %/built-in.a, $(filter-out %.a, $(libs-y)))
1061 virt-y := $(patsubst %/, %/built-in.a, $(virt-y))
1063 # Externally visible symbols (used by link-vmlinux.sh)
1064 export KBUILD_VMLINUX_OBJS := $(head-y) $(init-y) $(core-y) $(libs-y2) \
1065 $(drivers-y) $(net-y) $(virt-y)
1066 export KBUILD_VMLINUX_LIBS := $(libs-y1)
1067 export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
1068 export LDFLAGS_vmlinux
1069 # used by scripts/Makefile.package
1070 export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) LICENSES arch include scripts tools)
1072 vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
1074 # Recurse until adjust_autoksyms.sh is satisfied
1075 PHONY += autoksyms_recursive
1076 ifdef CONFIG_TRIM_UNUSED_KSYMS
1077 autoksyms_recursive: descend modules.order
1078 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1079 "$(MAKE) -f $(srctree)/Makefile autoksyms_recursive"
1082 # For the kernel to actually contain only the needed exported symbols,
1083 # we have to build modules as well to determine what those symbols are.
1084 # (this can be evaluated only once include/config/auto.conf has been included)
1085 ifdef CONFIG_TRIM_UNUSED_KSYMS
1089 autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1092 $(Q)mkdir -p $(dir $@)
1095 ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1097 # Final link of vmlinux with optional arch pass after final link
1098 cmd_link-vmlinux = \
1099 $(CONFIG_SHELL) $< $(LD) $(KBUILD_LDFLAGS) $(LDFLAGS_vmlinux) ; \
1100 $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1102 vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1103 +$(call if_changed,link-vmlinux)
1107 # The actual objects are generated when descending,
1108 # make sure no implicit rule kicks in
1109 $(sort $(vmlinux-deps)): descend ;
1111 filechk_kernel.release = \
1112 echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1114 # Store (new) KERNELRELEASE string in include/config/kernel.release
1115 include/config/kernel.release: FORCE
1116 $(call filechk,kernel.release)
1118 # Additional helpers built in scripts/
1119 # Carefully list dependencies so we do not try to build scripts twice
1122 scripts: scripts_basic scripts_dtc
1123 $(Q)$(MAKE) $(build)=$(@)
1125 # Things we need to do before we recursively start building the kernel
1126 # or the modules are listed in "prepare".
1127 # A multi level approach is used. prepareN is processed before prepareN-1.
1128 # archprepare is used in arch Makefiles and when processed asm symlink,
1129 # version.h and scripts_basic is processed / created.
1131 PHONY += prepare archprepare
1133 archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1134 asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h
1136 prepare0: archprepare
1137 $(Q)$(MAKE) $(build)=scripts/mod
1138 $(Q)$(MAKE) $(build)=.
1140 # All the preparing..
1141 prepare: prepare0 prepare-objtool
1143 # Support for using generic headers in asm-generic
1144 asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1146 PHONY += asm-generic uapi-asm-generic
1147 asm-generic: uapi-asm-generic
1148 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1149 generic=include/asm-generic
1151 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1152 generic=include/uapi/asm-generic
1154 PHONY += prepare-objtool
1155 prepare-objtool: $(objtool_target)
1156 ifeq ($(SKIP_STACK_VALIDATION),1)
1157 ifdef CONFIG_UNWINDER_ORC
1158 @echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1161 @echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1165 # Generate some files
1166 # ---------------------------------------------------------------------------
1168 # KERNELRELEASE can change from a few different places, meaning version.h
1169 # needs to be updated, so this check is forced on all builds
1172 define filechk_utsrelease.h
1173 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1174 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1177 echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1180 define filechk_version.h
1181 if [ $(SUBLEVEL) -gt 255 ]; then \
1182 echo \#define LINUX_VERSION_CODE $(shell \
1183 expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1185 echo \#define LINUX_VERSION_CODE $(shell \
1186 expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1188 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + \
1189 ((c) > 255 ? 255 : (c)))'
1192 $(version_h): PATCHLEVEL := $(if $(PATCHLEVEL), $(PATCHLEVEL), 0)
1193 $(version_h): SUBLEVEL := $(if $(SUBLEVEL), $(SUBLEVEL), 0)
1195 $(call filechk,version.h)
1196 $(Q)rm -f $(old_version_h)
1198 include/generated/utsrelease.h: include/config/kernel.release FORCE
1199 $(call filechk,utsrelease.h)
1203 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1204 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1206 # ---------------------------------------------------------------------------
1209 #Default location for installed headers
1210 export INSTALL_HDR_PATH = $(objtree)/usr
1212 quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1213 cmd_headers_install = \
1214 mkdir -p $(INSTALL_HDR_PATH); \
1215 rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1216 usr/include $(INSTALL_HDR_PATH)
1218 PHONY += headers_install
1219 headers_install: headers
1220 $(call cmd,headers_install)
1222 PHONY += archheaders archscripts
1224 hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1227 headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1228 $(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1229 $(error Headers not exportable for the $(SRCARCH) architecture))
1230 $(Q)$(MAKE) $(hdr-inst)=include/uapi
1231 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1233 # Deprecated. It is no-op now.
1234 PHONY += headers_check
1238 ifdef CONFIG_HEADERS_INSTALL
1242 PHONY += scripts_unifdef
1243 scripts_unifdef: scripts_basic
1244 $(Q)$(MAKE) $(build)=scripts scripts/unifdef
1246 # ---------------------------------------------------------------------------
1251 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1254 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1256 PHONY += kselftest-merge
1258 $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1259 $(Q)find $(srctree)/tools/testing/selftests -name config | \
1260 xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1261 $(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1263 # ---------------------------------------------------------------------------
1266 ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1267 dtstree := arch/$(SRCARCH)/boot/dts
1272 %.dtb: include/config/kernel.release scripts_dtc
1273 $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1275 PHONY += dtbs dtbs_install dtbs_check
1276 dtbs: include/config/kernel.release scripts_dtc
1277 $(Q)$(MAKE) $(build)=$(dtstree)
1279 ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1280 dtbs: dt_binding_check
1283 dtbs_check: export CHECK_DTBS=1
1287 $(Q)$(MAKE) $(dtbinst)=$(dtstree)
1289 ifdef CONFIG_OF_EARLY_FLATTREE
1295 PHONY += scripts_dtc
1296 scripts_dtc: scripts_basic
1297 $(Q)$(MAKE) $(build)=scripts/dtc
1299 PHONY += dt_binding_check
1300 dt_binding_check: scripts_dtc
1301 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1303 # ---------------------------------------------------------------------------
1306 ifdef CONFIG_MODULES
1308 # By default, build modules as well
1312 # When we're building modules with modversions, we need to consider
1313 # the built-in objects during the descend as well, in order to
1314 # make sure the checksums are up to date before we record them.
1315 ifdef CONFIG_MODVERSIONS
1321 # A module can be listed more than once in obj-m resulting in
1322 # duplicate lines in modules.order files. Those are removed
1323 # using awk while concatenating to the final file.
1326 modules: $(if $(KBUILD_BUILTIN),vmlinux) modules.order modules.builtin
1327 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1328 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh
1330 modules.order: descend
1331 $(Q)$(AWK) '!x[$$0]++' $(addsuffix /$@, $(build-dirs)) > $@
1333 modbuiltin-dirs := $(addprefix _modbuiltin_, $(build-dirs))
1335 modules.builtin: $(modbuiltin-dirs)
1336 $(Q)$(AWK) '!x[$$0]++' $(addsuffix /$@, $(build-dirs)) > $@
1338 PHONY += $(modbuiltin-dirs)
1339 # tristate.conf is not included from this Makefile. Add it as a prerequisite
1340 # here to make it self-healing in case somebody accidentally removes it.
1341 $(modbuiltin-dirs): include/config/tristate.conf
1342 $(Q)$(MAKE) $(modbuiltin)=$(patsubst _modbuiltin_%,%,$@)
1344 # Target to prepare building external modules
1345 PHONY += modules_prepare
1346 modules_prepare: prepare
1348 # Target to install modules
1349 PHONY += modules_install
1350 modules_install: _modinst_ _modinst_post
1354 @rm -rf $(MODLIB)/kernel
1355 @rm -f $(MODLIB)/source
1356 @mkdir -p $(MODLIB)/kernel
1357 @ln -s $(abspath $(srctree)) $(MODLIB)/source
1358 @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
1359 rm -f $(MODLIB)/build ; \
1360 ln -s $(CURDIR) $(MODLIB)/build ; \
1362 @sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order
1363 @sed 's:^:kernel/:' modules.builtin > $(MODLIB)/modules.builtin
1364 @cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
1365 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1367 # This depmod is only for convenience to give the initial
1368 # boot a modules.dep even before / is mounted read-write. However the
1369 # boot script depmod is the master version.
1370 PHONY += _modinst_post
1371 _modinst_post: _modinst_
1374 ifeq ($(CONFIG_MODULE_SIG), y)
1375 PHONY += modules_sign
1377 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1380 else # CONFIG_MODULES
1382 # Modules not configured
1383 # ---------------------------------------------------------------------------
1385 PHONY += modules modules_install
1386 modules modules_install:
1388 @echo >&2 "The present kernel configuration has modules disabled."
1389 @echo >&2 "Type 'make config' and enable loadable module support."
1390 @echo >&2 "Then build a kernel with module support enabled."
1394 endif # CONFIG_MODULES
1397 # Cleaning is done on three levels.
1398 # make clean Delete most generated files
1399 # Leave enough to build external modules
1400 # make mrproper Delete the current configuration, and all generated files
1401 # make distclean Remove editor backup files, patch leftover files and the like
1403 # Directories & files removed with 'make clean'
1404 CLEAN_DIRS += include/ksym
1405 CLEAN_FILES += modules.builtin.modinfo
1407 # Directories & files removed with 'make mrproper'
1408 MRPROPER_DIRS += include/config include/generated \
1409 arch/$(SRCARCH)/include/generated .tmp_objdiff \
1410 debian/ snap/ tar-install/
1411 MRPROPER_FILES += .config .config.old .version \
1413 signing_key.pem signing_key.priv signing_key.x509 \
1414 x509.genkey extra_certificates signing_key.x509.keyid \
1415 signing_key.x509.signer vmlinux-gdb.py \
1418 # Directories & files removed with 'make distclean'
1420 DISTCLEAN_FILES += tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS
1422 # clean - Delete most, but leave enough to build external modules
1424 clean: rm-dirs := $(CLEAN_DIRS)
1425 clean: rm-files := $(CLEAN_FILES)
1427 PHONY += archclean vmlinuxclean
1430 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1431 $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1433 clean: archclean vmlinuxclean
1435 # mrproper - Delete all generated files, including .config
1437 mrproper: rm-dirs := $(wildcard $(MRPROPER_DIRS))
1438 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1439 mrproper-dirs := $(addprefix _mrproper_,scripts)
1441 PHONY += $(mrproper-dirs) mrproper
1443 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1445 mrproper: clean $(mrproper-dirs)
1451 distclean: rm-dirs := $(wildcard $(DISTCLEAN_DIRS))
1452 distclean: rm-files := $(wildcard $(DISTCLEAN_FILES))
1459 @find $(srctree) $(RCS_FIND_IGNORE) \
1460 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1461 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1462 -o -name 'core' \) \
1463 -type f -print | xargs rm -f
1466 # Packaging of the kernel to various formats
1467 # ---------------------------------------------------------------------------
1470 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1471 %pkg: include/config/kernel.release FORCE
1472 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1474 # Brief documentation of the typical targets used
1475 # ---------------------------------------------------------------------------
1477 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1478 boards := $(sort $(notdir $(boards)))
1479 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1480 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1484 @echo 'Cleaning targets:'
1485 @echo ' clean - Remove most generated files but keep the config and'
1486 @echo ' enough build support to build external modules'
1487 @echo ' mrproper - Remove all generated files + config + various backup files'
1488 @echo ' distclean - mrproper + remove editor backup and patch files'
1490 @echo 'Configuration targets:'
1491 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1493 @echo 'Other generic targets:'
1494 @echo ' all - Build all targets marked with [*]'
1495 @echo '* vmlinux - Build the bare kernel'
1496 @echo '* modules - Build all modules'
1497 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1498 @echo ' dir/ - Build all files in dir and below'
1499 @echo ' dir/file.[ois] - Build specified target only'
1500 @echo ' dir/file.ll - Build the LLVM assembly file'
1501 @echo ' (requires compiler support for LLVM assembly generation)'
1502 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1503 @echo ' (requires a recent binutils and recent build (System.map))'
1504 @echo ' dir/file.ko - Build module including final link'
1505 @echo ' modules_prepare - Set up for building external modules'
1506 @echo ' tags/TAGS - Generate tags file for editors'
1507 @echo ' cscope - Generate cscope index'
1508 @echo ' gtags - Generate GNU GLOBAL index'
1509 @echo ' kernelrelease - Output the release version string (use with make -s)'
1510 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1511 @echo ' image_name - Output the image name (use with make -s)'
1512 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1513 echo ' (default: $(INSTALL_HDR_PATH))'; \
1515 @echo 'Static analysers:'
1516 @echo ' checkstack - Generate a list of stack hogs'
1517 @echo ' namespacecheck - Name space analysis on compiled kernel'
1518 @echo ' versioncheck - Sanity check on version.h usage'
1519 @echo ' includecheck - Check for duplicate included header files'
1520 @echo ' export_report - List the usages of all exported symbols'
1521 @echo ' headerdep - Detect inclusion cycles in headers'
1522 @echo ' coccicheck - Check with Coccinelle'
1525 @echo ' nsdeps - Generate missing symbol namespace dependencies'
1527 @echo 'Kernel selftest:'
1528 @echo ' kselftest - Build and run kernel selftest (run as root)'
1529 @echo ' Build, install, and boot kernel before'
1530 @echo ' running kselftest on it'
1531 @echo ' kselftest-clean - Remove all generated kselftest files'
1532 @echo ' kselftest-merge - Merge all the config dependencies of kselftest to existing'
1536 echo 'Devicetree:'; \
1537 echo '* dtbs - Build device tree blobs for enabled boards'; \
1538 echo ' dtbs_install - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1539 echo ' dt_binding_check - Validate device tree binding documents'; \
1540 echo ' dtbs_check - Validate device tree source files';\
1543 @echo 'Userspace tools targets:'
1544 @echo ' use "make tools/help"'
1545 @echo ' or "cd tools; make help"'
1547 @echo 'Kernel packaging:'
1548 @$(MAKE) -f $(srctree)/scripts/Makefile.package help
1550 @echo 'Documentation targets:'
1551 @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1553 @echo 'Architecture specific targets ($(SRCARCH)):'
1554 @$(if $(archhelp),$(archhelp),\
1555 echo ' No architecture specific help defined for $(SRCARCH)')
1558 $(foreach b, $(boards), \
1559 printf " %-24s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1561 @$(if $(board-dirs), \
1562 $(foreach b, $(board-dirs), \
1563 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1564 printf " %-16s - Show all of the above\\n" help-boards; \
1567 @echo ' make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1568 @echo ' make V=2 [targets] 2 => give reason for rebuild of target'
1569 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1570 @echo ' make C=1 [targets] Check re-compiled c source with $$CHECK (sparse by default)'
1571 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1572 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1573 @echo ' make W=n [targets] Enable extra build checks, n=1,2,3 where'
1574 @echo ' 1: warnings which may be relevant and do not occur too often'
1575 @echo ' 2: warnings which occur quite often but may still be relevant'
1576 @echo ' 3: more obscure warnings, can most likely be ignored'
1577 @echo ' Multiple levels can be combined with W=12 or W=123'
1579 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1580 @echo 'For further info see the ./README file'
1583 help-board-dirs := $(addprefix help-,$(board-dirs))
1585 help-boards: $(help-board-dirs)
1587 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1589 $(help-board-dirs): help-%:
1590 @echo 'Architecture specific targets ($(SRCARCH) $*):'
1591 @$(if $(boards-per-dir), \
1592 $(foreach b, $(boards-per-dir), \
1593 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1597 # Documentation targets
1598 # ---------------------------------------------------------------------------
1599 DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1600 linkcheckdocs dochelp refcheckdocs
1601 PHONY += $(DOC_TARGETS)
1603 $(Q)$(MAKE) $(build)=Documentation $@
1606 # ---------------------------------------------------------------------------
1608 PHONY += scripts_gdb
1609 scripts_gdb: prepare0
1610 $(Q)$(MAKE) $(build)=scripts/gdb
1611 $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1613 ifdef CONFIG_GDB_SCRIPTS
1617 else # KBUILD_EXTMOD
1620 # External module support.
1621 # When building external modules the kernel used as basis is considered
1622 # read-only, and no consistency checks are made and the make
1623 # system is not used on the basis kernel. If updates are required
1624 # in the basis kernel ordinary make commands (without M=...) must
1627 # The following are the only valid targets when building external
1629 # make M=dir clean Delete all automatically generated files
1630 # make M=dir modules Make all modules in specified dir
1631 # make M=dir Same as 'make M=dir modules'
1632 # make M=dir modules_install
1633 # Install the modules built in the module directory
1634 # Assumes install directory is already created
1636 # We are always building modules
1639 PHONY += $(objtree)/Module.symvers
1640 $(objtree)/Module.symvers:
1641 @test -e $(objtree)/Module.symvers || ( \
1643 echo " WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1644 echo " is missing; modules will have no dependencies and modversions."; \
1647 build-dirs := $(KBUILD_EXTMOD)
1649 modules: descend $(objtree)/Module.symvers
1650 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1652 PHONY += modules_install
1653 modules_install: _emodinst_ _emodinst_post
1655 install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1658 $(Q)mkdir -p $(MODLIB)/$(install-dir)
1659 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1661 PHONY += _emodinst_post
1662 _emodinst_post: _emodinst_
1665 clean-dirs := $(KBUILD_EXTMOD)
1666 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers
1670 @echo >&2 '"$(MAKE) /" is no longer supported. Please use "$(MAKE) ./" instead.'
1674 @echo ' Building external modules.'
1675 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1677 @echo ' modules - default target, build the module(s)'
1678 @echo ' modules_install - install the module'
1679 @echo ' clean - remove generated files in module directory only'
1683 endif # KBUILD_EXTMOD
1686 # ---------------------------------------------------------------------------
1687 # To build individual files in subdirectories, you can do like this:
1689 # make foo/bar/baz.s
1691 # The supported suffixes for single-target are listed in 'single-targets'
1693 # To build only under specific subdirectories, you can do like this:
1699 # .ko is special because modpost is needed
1700 single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1701 single-no-ko := $(sort $(patsubst %.ko,%.mod, $(MAKECMDGOALS)))
1703 $(single-ko): single_modpost
1705 $(single-no-ko): descend
1708 ifeq ($(KBUILD_EXTMOD),)
1709 # For the single build of in-tree modules, use a temporary file to avoid
1710 # the situation of modules_install installing an invalid modules.order.
1711 MODORDER := .modules.tmp
1714 PHONY += single_modpost
1715 single_modpost: $(single-no-ko)
1716 $(Q){ $(foreach m, $(single-ko), echo $(extmod-prefix)$m;) } > $(MODORDER)
1717 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1721 export KBUILD_SINGLE_TARGETS := $(addprefix $(extmod-prefix), $(single-no-ko))
1723 # trim unrelated directories
1724 build-dirs := $(foreach d, $(build-dirs), \
1725 $(if $(filter $(d)/%, $(KBUILD_SINGLE_TARGETS)), $(d)))
1729 # Handle descending into subdirectories listed in $(build-dirs)
1730 # Preset locale variables to speed up the build process. Limit locale
1731 # tweaks to this spot to avoid wrong language settings when running
1732 # make menuconfig etc.
1733 # Error messages still appears in the original language
1734 PHONY += descend $(build-dirs)
1735 descend: $(build-dirs)
1736 $(build-dirs): prepare
1737 $(Q)$(MAKE) $(build)=$@ \
1738 single-build=$(if $(filter-out $@/, $(single-no-ko)),1) \
1739 need-builtin=1 need-modorder=1
1741 clean-dirs := $(addprefix _clean_, $(clean-dirs))
1742 PHONY += $(clean-dirs) clean
1744 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1746 clean: $(clean-dirs)
1749 @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1750 \( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1752 -o -name '*.dtb' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1753 -o -name '*.dwo' -o -name '*.lst' \
1754 -o -name '*.su' -o -name '*.mod' -o -name '*.ns_deps' \
1755 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1756 -o -name '*.lex.c' -o -name '*.tab.[ch]' \
1757 -o -name '*.asn1.[ch]' \
1758 -o -name '*.symtypes' -o -name 'modules.order' \
1759 -o -name modules.builtin -o -name '.tmp_*.o.*' \
1760 -o -name '*.c.[012]*.*' \
1762 -o -name '*.gcno' \) -type f -print | xargs rm -f
1764 # Generate tags for editors
1765 # ---------------------------------------------------------------------------
1766 quiet_cmd_tags = GEN $@
1767 cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1769 tags TAGS cscope gtags: FORCE
1772 # Script to generate missing namespace dependencies
1773 # ---------------------------------------------------------------------------
1778 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost nsdeps
1779 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/$@
1781 # Scripts to check various things for consistency
1782 # ---------------------------------------------------------------------------
1784 PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1787 find $(srctree)/* $(RCS_FIND_IGNORE) \
1788 -name '*.[hcS]' -type f -print | sort \
1789 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1792 find $(srctree)/* $(RCS_FIND_IGNORE) \
1793 -name '*.[hcS]' -type f -print | sort \
1794 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1797 $(Q)$(BASH) $(srctree)/scripts/$@
1800 $(PERL) $(srctree)/scripts/namespace.pl
1803 $(PERL) $(srctree)/scripts/export_report.pl
1805 PHONY += checkstack kernelrelease kernelversion image_name
1807 # UML needs a little special treatment here. It wants to use the host
1808 # toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
1809 # else wants $(ARCH), including people doing cross-builds, which means
1810 # that $(SUBARCH) doesn't work here.
1812 CHECKSTACK_ARCH := $(SUBARCH)
1814 CHECKSTACK_ARCH := $(ARCH)
1817 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1818 $(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1821 @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1824 @echo $(KERNELVERSION)
1827 @echo $(KBUILD_IMAGE)
1829 # Clear a bunch of variables before executing the submake
1831 ifeq ($(quiet),silent_)
1836 $(Q)mkdir -p $(objtree)/tools
1837 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1840 $(Q)mkdir -p $(objtree)/tools
1841 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1843 # FIXME Should go into a make.lib or something
1844 # ===========================================================================
1846 quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN $(wildcard $(rm-dirs)))
1847 cmd_rmdirs = rm -rf $(rm-dirs)
1849 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
1850 cmd_rmfiles = rm -f $(rm-files)
1852 # Run depmod only if we have System.map and depmod is executable
1853 quiet_cmd_depmod = DEPMOD $(KERNELRELEASE)
1854 cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1857 # read saved command lines for existing targets
1858 existing-targets := $(wildcard $(sort $(targets)))
1860 -include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
1862 endif # config-targets
1864 endif # need-sub-make
1869 # Declare the contents of the PHONY variable as phony. We keep that
1870 # information in a variable so we can use it in if_changed and friends.