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 # 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 = $(C)
205 ifndef KBUILD_CHECKSRC
209 # Use make M=dir to specify directory of external module to build
210 # Old syntax make ... SUBDIRS=$PWD is still supported
211 # Setting the environment variable KBUILD_EXTMOD take precedence
213 $(warning ================= WARNING ================)
214 $(warning 'SUBDIRS' will be removed after Linux 5.3)
215 $(warning Please use 'M=' or 'KBUILD_EXTMOD' instead)
216 $(warning ==========================================)
217 KBUILD_EXTMOD ?= $(SUBDIRS)
220 ifeq ("$(origin M)", "command line")
221 KBUILD_EXTMOD := $(M)
224 ifeq ($(abs_srctree),$(abs_objtree))
225 # building in the source tree
228 ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
229 # building in a subdirectory of the source tree
232 srctree := $(abs_srctree)
236 # KBUILD_SRC is only used to distinguish in-tree/out-of-tree build.
237 # Replace it with $(srctree) or something.
238 KBUILD_SRC := $(abs_srctree)
241 export KBUILD_CHECKSRC KBUILD_EXTMOD KBUILD_SRC
249 export srctree objtree VPATH
251 # To make sure we do not include .config for any of the *config targets
252 # catch them early, and hand them over to scripts/kconfig/Makefile
253 # It is allowed to specify more targets when calling make, including
254 # mixing *config targets and build targets.
255 # For example 'make oldconfig all'.
256 # Detect when mixed targets is specified, and make a second invocation
257 # of make so .config is not included in this case either (for *config).
259 version_h := include/generated/uapi/linux/version.h
260 old_version_h := include/linux/version.h
262 clean-targets := %clean mrproper cleandocs
263 no-dot-config-targets := $(clean-targets) \
264 cscope gtags TAGS tags help% %docs check% coccicheck \
265 $(version_h) headers headers_% archheaders archscripts \
266 %asm-generic kernelversion %src-pkg
267 no-sync-config-targets := $(no-dot-config-targets) install %install \
275 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
276 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
281 ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
282 ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
287 ifneq ($(KBUILD_EXTMOD),)
291 ifeq ($(KBUILD_EXTMOD),)
292 ifneq ($(filter config %config,$(MAKECMDGOALS)),)
294 ifneq ($(words $(MAKECMDGOALS)),1)
300 # For "make -j clean all", "make -j mrproper defconfig all", etc.
301 ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
302 ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
307 # install and modules_install need also be processed one by one
308 ifneq ($(filter install,$(MAKECMDGOALS)),)
309 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
314 ifeq ($(mixed-targets),1)
315 # ===========================================================================
316 # We're called with mixed targets (*config and build targets).
317 # Handle them one by one.
319 PHONY += $(MAKECMDGOALS) __build_one_by_one
321 $(filter-out __build_one_by_one, $(MAKECMDGOALS)): __build_one_by_one
326 for i in $(MAKECMDGOALS); do \
327 $(MAKE) -f $(srctree)/Makefile $$i; \
332 include scripts/Kbuild.include
334 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
335 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
336 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
337 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
339 include scripts/subarch.include
341 # Cross compiling and selecting different set of gcc/bin-utils
342 # ---------------------------------------------------------------------------
344 # When performing cross compilation for other architectures ARCH shall be set
345 # to the target architecture. (See arch/* for the possibilities).
346 # ARCH can be set during invocation of make:
348 # Another way is to have ARCH set in the environment.
349 # The default ARCH is the host where make is executed.
351 # CROSS_COMPILE specify the prefix used for all executables used
352 # during compilation. Only gcc and related bin-utils executables
353 # are prefixed with $(CROSS_COMPILE).
354 # CROSS_COMPILE can be set on the command line
355 # make CROSS_COMPILE=ia64-linux-
356 # Alternatively CROSS_COMPILE can be set in the environment.
357 # Default value for CROSS_COMPILE is not to prefix executables
358 # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
361 # Architecture as present in compile.h
362 UTS_MACHINE := $(ARCH)
365 # Additional ARCH settings for x86
369 ifeq ($(ARCH),x86_64)
373 # Additional ARCH settings for sparc
374 ifeq ($(ARCH),sparc32)
377 ifeq ($(ARCH),sparc64)
381 # Additional ARCH settings for sh
386 KCONFIG_CONFIG ?= .config
387 export KCONFIG_CONFIG
389 # SHELL used by kbuild
390 CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
391 else if [ -x /bin/bash ]; then echo /bin/bash; \
392 else echo sh; fi ; fi)
394 HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
395 HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
396 HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
400 KBUILD_HOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 \
401 -fomit-frame-pointer -std=gnu89 $(HOST_LFS_CFLAGS) \
403 KBUILD_HOSTCXXFLAGS := -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
404 KBUILD_HOSTLDFLAGS := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
405 KBUILD_HOSTLDLIBS := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
407 # Make variables (CC, etc...)
408 AS = $(CROSS_COMPILE)as
409 LD = $(CROSS_COMPILE)ld
410 CC = $(CROSS_COMPILE)gcc
412 AR = $(CROSS_COMPILE)ar
413 NM = $(CROSS_COMPILE)nm
414 STRIP = $(CROSS_COMPILE)strip
415 OBJCOPY = $(CROSS_COMPILE)objcopy
416 OBJDUMP = $(CROSS_COMPILE)objdump
421 INSTALLKERNEL := installkernel
422 DEPMOD = /sbin/depmod
429 CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
430 -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
439 # Use USERINCLUDE when you must reference the UAPI directories only.
441 -I$(srctree)/arch/$(SRCARCH)/include/uapi \
442 -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
443 -I$(srctree)/include/uapi \
444 -I$(objtree)/include/generated/uapi \
445 -include $(srctree)/include/linux/kconfig.h
447 # Use LINUXINCLUDE when you must reference the include/ directory.
448 # Needed to be compatible with the O= option
450 -I$(srctree)/arch/$(SRCARCH)/include \
451 -I$(objtree)/arch/$(SRCARCH)/include/generated \
452 $(if $(filter .,$(srctree)),,-I$(srctree)/include) \
453 -I$(objtree)/include \
456 KBUILD_AFLAGS := -D__ASSEMBLY__ -fno-PIE
457 KBUILD_CFLAGS := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
458 -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
459 -Werror=implicit-function-declaration -Werror=implicit-int \
460 -Wno-format-security \
462 KBUILD_CPPFLAGS := -D__KERNEL__
463 KBUILD_AFLAGS_KERNEL :=
464 KBUILD_CFLAGS_KERNEL :=
465 KBUILD_AFLAGS_MODULE := -DMODULE
466 KBUILD_CFLAGS_MODULE := -DMODULE
467 KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
469 GCC_PLUGINS_CFLAGS :=
471 export ARCH SRCARCH CONFIG_SHELL HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE AS LD CC
472 export CPP AR NM STRIP OBJCOPY OBJDUMP PAHOLE KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS
473 export MAKE LEX YACC AWK INSTALLKERNEL PERL PYTHON PYTHON2 PYTHON3 UTS_MACHINE
474 export HOSTCXX KBUILD_HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
476 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
477 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
478 export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN
479 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
480 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
481 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
482 export KBUILD_ARFLAGS
484 # When compiling out-of-tree modules, put MODVERDIR in the module
485 # tree rather than in the kernel tree. The kernel tree might
487 export MODVERDIR := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_versions
489 # Files to ignore in find ... statements
491 export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o \
492 -name CVS -o -name .pc -o -name .hg -o -name .git \) \
494 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
495 --exclude CVS --exclude .pc --exclude .hg --exclude .git
497 # ===========================================================================
498 # Rules shared between *config targets and build targets
500 # Basic helpers built in scripts/basic/
501 PHONY += scripts_basic
503 $(Q)$(MAKE) $(build)=scripts/basic
504 $(Q)rm -f .tmp_quiet_recordmcount
506 PHONY += outputmakefile
507 # outputmakefile generates a Makefile in the output directory, if using a
508 # separate output directory. This allows convenient use of make in the
510 # At the same time when output Makefile generated, generate .gitignore to
511 # ignore whole output directory
514 $(Q)ln -fsn $(srctree) source
515 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile $(srctree)
516 $(Q)test -e .gitignore || \
517 { echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
520 ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),)
521 ifneq ($(CROSS_COMPILE),)
522 CLANG_FLAGS := --target=$(notdir $(CROSS_COMPILE:%-=%))
523 GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
524 CLANG_FLAGS += --prefix=$(GCC_TOOLCHAIN_DIR)
525 GCC_TOOLCHAIN := $(realpath $(GCC_TOOLCHAIN_DIR)/..)
527 ifneq ($(GCC_TOOLCHAIN),)
528 CLANG_FLAGS += --gcc-toolchain=$(GCC_TOOLCHAIN)
530 CLANG_FLAGS += -no-integrated-as
531 CLANG_FLAGS += -Werror=unknown-warning-option
532 KBUILD_CFLAGS += $(CLANG_FLAGS)
533 KBUILD_AFLAGS += $(CLANG_FLAGS)
537 # The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
538 # Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
539 # CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
540 # and from include/config/auto.conf.cmd to detect the compiler upgrade.
541 CC_VERSION_TEXT = $(shell $(CC) --version 2>/dev/null | head -n 1)
543 ifeq ($(config-targets),1)
544 # ===========================================================================
545 # *config targets only - make sure prerequisites are updated, and descend
546 # in scripts/kconfig to make the *config target
548 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
549 # KBUILD_DEFCONFIG may point out an alternative default configuration
550 # used for 'make defconfig'
551 include arch/$(SRCARCH)/Makefile
552 export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
554 config: scripts_basic outputmakefile FORCE
555 $(Q)$(MAKE) $(build)=scripts/kconfig $@
557 %config: scripts_basic outputmakefile FORCE
558 $(Q)$(MAKE) $(build)=scripts/kconfig $@
561 # ===========================================================================
562 # Build targets only - this includes vmlinux, arch specific targets, clean
563 # targets and others. In general all targets except *config targets.
565 # If building an external module we do not care about the all: rule
566 # but instead _all depend on modules
568 ifeq ($(KBUILD_EXTMOD),)
574 # Decide whether to build built-in, modular, or both.
575 # Normally, just do built-in.
580 # If we have only "make modules", don't compile built-in objects.
581 # When we're building modules with modversions, we need to consider
582 # the built-in objects during the descend as well, in order to
583 # make sure the checksums are up to date before we record them.
585 ifeq ($(MAKECMDGOALS),modules)
586 KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
589 # If we have "make <whatever> modules", compile modules
590 # in addition to whatever we do anyway.
591 # Just "make" or "make all" shall build modules as well
593 ifneq ($(filter all _all modules,$(MAKECMDGOALS)),)
597 ifeq ($(MAKECMDGOALS),)
601 export KBUILD_MODULES KBUILD_BUILTIN
603 ifeq ($(dot-config),1)
604 include include/config/auto.conf
607 ifeq ($(KBUILD_EXTMOD),)
608 # Objects we will link into vmlinux / subdirs we need to visit
610 drivers-y := drivers/ sound/
611 drivers-$(CONFIG_SAMPLES) += samples/
616 endif # KBUILD_EXTMOD
618 # The all: target is the default when no target is given on the
620 # This allow a user to issue only 'make' to build a kernel including modules
621 # Defaults to vmlinux, but the arch makefile usually adds further targets
624 CFLAGS_GCOV := -fprofile-arcs -ftest-coverage \
625 $(call cc-option,-fno-tree-loop-im) \
626 $(call cc-disable-warning,maybe-uninitialized,)
629 # The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
630 ifdef CONFIG_FUNCTION_TRACER
631 CC_FLAGS_FTRACE := -pg
634 RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
635 RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
636 RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
637 RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
638 RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
639 RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
640 export RETPOLINE_CFLAGS
641 export RETPOLINE_VDSO_CFLAGS
643 # The arch Makefile can set ARCH_{CPP,A,C}FLAGS to override the default
644 # values of the respective KBUILD_* variables
648 include arch/$(SRCARCH)/Makefile
650 ifeq ($(dot-config),1)
651 ifeq ($(may-sync-config),1)
652 # Read in dependencies to all Kconfig* files, make sure to run syncconfig if
653 # changes are detected. This should be included after arch/$(SRCARCH)/Makefile
654 # because some architectures define CROSS_COMPILE there.
655 include include/config/auto.conf.cmd
659 @echo >&2 '*** Configuration file "$@" not found!'
661 @echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
662 @echo >&2 '*** "make menuconfig" or "make xconfig").'
666 # The actual configuration files used during the build are stored in
667 # include/generated/ and include/config/. Update them if .config is newer than
668 # include/config/auto.conf (which mirrors .config).
670 # This exploits the 'multi-target pattern rule' trick.
671 # The syncconfig should be executed only once to make all the targets.
672 %/auto.conf %/auto.conf.cmd %/tristate.conf: $(KCONFIG_CONFIG)
673 $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
675 # External modules and some install targets need include/generated/autoconf.h
676 # and include/config/auto.conf but do not care if they are up-to-date.
677 # Use auto.conf to trigger the test
678 PHONY += include/config/auto.conf
680 include/config/auto.conf:
681 $(Q)test -e include/generated/autoconf.h -a -e $@ || ( \
683 echo >&2 " ERROR: Kernel configuration is invalid."; \
684 echo >&2 " include/generated/autoconf.h or $@ are missing.";\
685 echo >&2 " Run 'make oldconfig && make prepare' on kernel src to fix it."; \
689 endif # may-sync-config
690 endif # $(dot-config)
692 KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,)
693 KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,)
694 KBUILD_CFLAGS += $(call cc-disable-warning, format-truncation)
695 KBUILD_CFLAGS += $(call cc-disable-warning, format-overflow)
696 KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
698 ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
704 ifdef CONFIG_CC_DISABLE_WARN_MAYBE_UNINITIALIZED
705 KBUILD_CFLAGS += -Wno-maybe-uninitialized
708 # Tell gcc to never replace conditional load with a non-conditional one
709 KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
711 include scripts/Makefile.kcov
712 include scripts/Makefile.gcc-plugins
714 ifdef CONFIG_READABLE_ASM
715 # Disable optimizations that make assembler listings hard to read.
716 # reorder blocks reorders the control in the function
717 # ipa clone creates specialized cloned functions
718 # partial inlining inlines only parts of functions
719 KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
720 $(call cc-option,-fno-ipa-cp-clone,) \
721 $(call cc-option,-fno-partial-inlining)
724 ifneq ($(CONFIG_FRAME_WARN),0)
725 KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
728 stackp-flags-$(CONFIG_CC_HAS_STACKPROTECTOR_NONE) := -fno-stack-protector
729 stackp-flags-$(CONFIG_STACKPROTECTOR) := -fstack-protector
730 stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG) := -fstack-protector-strong
732 KBUILD_CFLAGS += $(stackp-flags-y)
734 ifdef CONFIG_CC_IS_CLANG
735 KBUILD_CPPFLAGS += -Qunused-arguments
736 KBUILD_CFLAGS += -Wno-format-invalid-specifier
737 KBUILD_CFLAGS += -Wno-gnu
738 # Quiet clang warning: comparison of unsigned expression < 0 is always false
739 KBUILD_CFLAGS += -Wno-tautological-compare
740 # CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
741 # source of a reference will be _MergedGlobals and not on of the whitelisted names.
742 # See modpost pattern 2
743 KBUILD_CFLAGS += -mno-global-merge
746 # These warnings generated too much noise in a regular build.
747 # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
748 KBUILD_CFLAGS += -Wno-unused-but-set-variable
751 KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
752 ifdef CONFIG_FRAME_POINTER
753 KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
755 # Some targets (ARM with Thumb2, for example), can't be built with frame
756 # pointers. For those, we don't have FUNCTION_TRACER automatically
757 # select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
758 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
759 # -fomit-frame-pointer with FUNCTION_TRACER.
760 ifndef CONFIG_FUNCTION_TRACER
761 KBUILD_CFLAGS += -fomit-frame-pointer
765 # Initialize all stack variables with a pattern, if desired.
766 ifdef CONFIG_INIT_STACK_ALL
767 KBUILD_CFLAGS += -ftrivial-auto-var-init=pattern
770 DEBUG_CFLAGS := $(call cc-option, -fno-var-tracking-assignments)
772 ifdef CONFIG_DEBUG_INFO
773 ifdef CONFIG_DEBUG_INFO_SPLIT
774 DEBUG_CFLAGS += -gsplit-dwarf
778 KBUILD_AFLAGS += -Wa,-gdwarf-2
780 ifdef CONFIG_DEBUG_INFO_DWARF4
781 DEBUG_CFLAGS += -gdwarf-4
784 ifdef CONFIG_DEBUG_INFO_REDUCED
785 DEBUG_CFLAGS += $(call cc-option, -femit-struct-debug-baseonly) \
786 $(call cc-option,-fno-var-tracking)
789 KBUILD_CFLAGS += $(DEBUG_CFLAGS)
792 ifdef CONFIG_FUNCTION_TRACER
793 ifdef CONFIG_FTRACE_MCOUNT_RECORD
794 # gcc 5 supports generating the mcount tables directly
795 ifeq ($(call cc-option-yn,-mrecord-mcount),y)
796 CC_FLAGS_FTRACE += -mrecord-mcount
797 export CC_USING_RECORD_MCOUNT := 1
799 ifdef CONFIG_HAVE_NOP_MCOUNT
800 ifeq ($(call cc-option-yn, -mnop-mcount),y)
801 CC_FLAGS_FTRACE += -mnop-mcount
802 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
806 ifdef CONFIG_HAVE_FENTRY
807 ifeq ($(call cc-option-yn, -mfentry),y)
808 CC_FLAGS_FTRACE += -mfentry
809 CC_FLAGS_USING += -DCC_USING_FENTRY
812 export CC_FLAGS_FTRACE
813 KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
814 KBUILD_AFLAGS += $(CC_FLAGS_USING)
815 ifdef CONFIG_DYNAMIC_FTRACE
816 ifdef CONFIG_HAVE_C_RECORDMCOUNT
817 BUILD_C_RECORDMCOUNT := y
818 export BUILD_C_RECORDMCOUNT
823 # We trigger additional mismatches with less inlining
824 ifdef CONFIG_DEBUG_SECTION_MISMATCH
825 KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
828 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
829 KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
830 LDFLAGS_vmlinux += --gc-sections
833 ifdef CONFIG_LIVEPATCH
834 KBUILD_CFLAGS += $(call cc-option, -flive-patching=inline-clone)
837 # arch Makefile may override CC so keep this after arch Makefile is included
838 NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
840 # warn about C99 declaration after statement
841 KBUILD_CFLAGS += -Wdeclaration-after-statement
843 # Variable Length Arrays (VLAs) should not be used anywhere in the kernel
844 KBUILD_CFLAGS += -Wvla
846 # disable pointer signed / unsigned warnings in gcc 4.0
847 KBUILD_CFLAGS += -Wno-pointer-sign
849 # disable stringop warnings in gcc 8+
850 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
852 # disable invalid "can't wrap" optimizations for signed / pointers
853 KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow)
855 # clang sets -fmerge-all-constants by default as optimization, but this
856 # is non-conforming behavior for C and in fact breaks the kernel, so we
857 # need to disable it here generally.
858 KBUILD_CFLAGS += $(call cc-option,-fno-merge-all-constants)
860 # for gcc -fno-merge-all-constants disables everything, but it is fine
861 # to have actual conforming behavior enabled.
862 KBUILD_CFLAGS += $(call cc-option,-fmerge-constants)
864 # Make sure -fstack-check isn't enabled (like gentoo apparently did)
865 KBUILD_CFLAGS += $(call cc-option,-fno-stack-check,)
867 # conserve stack if available
868 KBUILD_CFLAGS += $(call cc-option,-fconserve-stack)
870 # Prohibit date/time macros, which would make the build non-deterministic
871 KBUILD_CFLAGS += $(call cc-option,-Werror=date-time)
873 # enforce correct pointer usage
874 KBUILD_CFLAGS += $(call cc-option,-Werror=incompatible-pointer-types)
876 # Require designated initializers for all marked structures
877 KBUILD_CFLAGS += $(call cc-option,-Werror=designated-init)
879 # change __FILE__ to the relative path from the srctree
880 KBUILD_CFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
882 # use the deterministic mode of AR if available
883 KBUILD_ARFLAGS := $(call ar-option,D)
885 include scripts/Makefile.kasan
886 include scripts/Makefile.extrawarn
887 include scripts/Makefile.ubsan
889 # Add any arch overrides and user supplied CPPFLAGS, AFLAGS and CFLAGS as the
891 KBUILD_CPPFLAGS += $(ARCH_CPPFLAGS) $(KCPPFLAGS)
892 KBUILD_AFLAGS += $(ARCH_AFLAGS) $(KAFLAGS)
893 KBUILD_CFLAGS += $(ARCH_CFLAGS) $(KCFLAGS)
895 # Use --build-id when available.
896 LDFLAGS_BUILD_ID := $(call ld-option, --build-id)
897 KBUILD_LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID)
898 LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)
900 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
901 LDFLAGS_vmlinux += $(call ld-option, -X,)
904 # insure the checker run with the right endianness
905 CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
907 # the checker needs the correct machine size
908 CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
910 # Default kernel image to build when no specific target is given.
911 # KBUILD_IMAGE may be overruled on the command line or
912 # set in the environment
913 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
915 export KBUILD_IMAGE ?= vmlinux
918 # INSTALL_PATH specifies where to place the updated kernel and system map
919 # images. Default is /boot, but you can set it to other values
920 export INSTALL_PATH ?= /boot
923 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
924 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
925 # an argument if needed. Otherwise it defaults to the kernel install path
927 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
930 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
931 # relocations required by build roots. This is not defined in the
932 # makefile but the argument can be passed to make if needed.
935 MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
939 # INSTALL_MOD_STRIP, if defined, will cause modules to be
940 # stripped after they are installed. If INSTALL_MOD_STRIP is '1', then
941 # the default option --strip-debug will be used. Otherwise,
942 # INSTALL_MOD_STRIP value will be used as the options to the strip command.
944 ifdef INSTALL_MOD_STRIP
945 ifeq ($(INSTALL_MOD_STRIP),1)
946 mod_strip_cmd = $(STRIP) --strip-debug
948 mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
949 endif # INSTALL_MOD_STRIP=1
952 endif # INSTALL_MOD_STRIP
955 # CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
956 # after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
957 # or CONFIG_MODULE_COMPRESS_XZ.
959 mod_compress_cmd = true
960 ifdef CONFIG_MODULE_COMPRESS
961 ifdef CONFIG_MODULE_COMPRESS_GZIP
962 mod_compress_cmd = gzip -n -f
963 endif # CONFIG_MODULE_COMPRESS_GZIP
964 ifdef CONFIG_MODULE_COMPRESS_XZ
965 mod_compress_cmd = xz -f
966 endif # CONFIG_MODULE_COMPRESS_XZ
967 endif # CONFIG_MODULE_COMPRESS
968 export mod_compress_cmd
970 ifdef CONFIG_MODULE_SIG_ALL
971 $(eval $(call config_filename,MODULE_SIG_KEY))
973 mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
979 HOST_LIBELF_LIBS = $(shell pkg-config libelf --libs 2>/dev/null || echo -lelf)
981 ifdef CONFIG_STACK_VALIDATION
982 has_libelf := $(call try-run,\
983 echo "int main() {}" | $(HOSTCC) -xc -o /dev/null $(HOST_LIBELF_LIBS) -,1,0)
984 ifeq ($(has_libelf),1)
985 objtool_target := tools/objtool FORCE
987 SKIP_STACK_VALIDATION := 1
988 export SKIP_STACK_VALIDATION
994 ifeq ($(KBUILD_EXTMOD),)
995 core-y += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
997 vmlinux-dirs := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
998 $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
999 $(net-y) $(net-m) $(libs-y) $(libs-m) $(virt-y)))
1001 vmlinux-alldirs := $(sort $(vmlinux-dirs) Documentation \
1002 $(patsubst %/,%,$(filter %/, $(init-) $(core-) \
1003 $(drivers-) $(net-) $(libs-) $(virt-))))
1005 init-y := $(patsubst %/, %/built-in.a, $(init-y))
1006 core-y := $(patsubst %/, %/built-in.a, $(core-y))
1007 drivers-y := $(patsubst %/, %/built-in.a, $(drivers-y))
1008 net-y := $(patsubst %/, %/built-in.a, $(net-y))
1009 libs-y1 := $(patsubst %/, %/lib.a, $(libs-y))
1010 libs-y2 := $(patsubst %/, %/built-in.a, $(filter-out %.a, $(libs-y)))
1011 virt-y := $(patsubst %/, %/built-in.a, $(virt-y))
1013 # Externally visible symbols (used by link-vmlinux.sh)
1014 export KBUILD_VMLINUX_OBJS := $(head-y) $(init-y) $(core-y) $(libs-y2) \
1015 $(drivers-y) $(net-y) $(virt-y)
1016 export KBUILD_VMLINUX_LIBS := $(libs-y1)
1017 export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
1018 export LDFLAGS_vmlinux
1019 # used by scripts/package/Makefile
1020 export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) LICENSES arch include scripts tools)
1022 vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
1024 # Recurse until adjust_autoksyms.sh is satisfied
1025 PHONY += autoksyms_recursive
1026 autoksyms_recursive: $(vmlinux-deps)
1027 ifdef CONFIG_TRIM_UNUSED_KSYMS
1028 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1029 "$(MAKE) -f $(srctree)/Makefile vmlinux"
1032 # For the kernel to actually contain only the needed exported symbols,
1033 # we have to build modules as well to determine what those symbols are.
1034 # (this can be evaluated only once include/config/auto.conf has been included)
1035 ifdef CONFIG_TRIM_UNUSED_KSYMS
1039 autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1042 $(Q)mkdir -p $(dir $@)
1045 ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1047 # Final link of vmlinux with optional arch pass after final link
1048 cmd_link-vmlinux = \
1049 $(CONFIG_SHELL) $< $(LD) $(KBUILD_LDFLAGS) $(LDFLAGS_vmlinux) ; \
1050 $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1052 vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1053 +$(call if_changed,link-vmlinux)
1057 # The actual objects are generated when descending,
1058 # make sure no implicit rule kicks in
1059 $(sort $(vmlinux-deps)): $(vmlinux-dirs) ;
1061 # Handle descending into subdirectories listed in $(vmlinux-dirs)
1062 # Preset locale variables to speed up the build process. Limit locale
1063 # tweaks to this spot to avoid wrong language settings when running
1064 # make menuconfig etc.
1065 # Error messages still appears in the original language
1067 PHONY += $(vmlinux-dirs)
1068 $(vmlinux-dirs): prepare
1069 $(Q)$(MAKE) $(build)=$@ need-builtin=1
1071 filechk_kernel.release = \
1072 echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1074 # Store (new) KERNELRELEASE string in include/config/kernel.release
1075 include/config/kernel.release: FORCE
1076 $(call filechk,kernel.release)
1078 # Additional helpers built in scripts/
1079 # Carefully list dependencies so we do not try to build scripts twice
1082 scripts: scripts_basic scripts_dtc
1083 $(Q)$(MAKE) $(build)=$(@)
1085 # Things we need to do before we recursively start building the kernel
1086 # or the modules are listed in "prepare".
1087 # A multi level approach is used. prepareN is processed before prepareN-1.
1088 # archprepare is used in arch Makefiles and when processed asm symlink,
1089 # version.h and scripts_basic is processed / created.
1091 PHONY += prepare archprepare prepare1 prepare3
1093 # prepare3 is used to check if we are building in a separate output directory,
1095 # 1) Check that make has not been executed in the kernel src $(srctree)
1096 prepare3: include/config/kernel.release
1097 ifneq ($(srctree),.)
1098 @$(kecho) ' Using $(srctree) as source for kernel'
1099 $(Q)if [ -f $(srctree)/.config -o \
1100 -d $(srctree)/include/config -o \
1101 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
1102 echo >&2 " $(srctree) is not clean, please run 'make mrproper'"; \
1103 echo >&2 " in the '$(srctree)' directory.";\
1108 prepare1: prepare3 outputmakefile asm-generic $(version_h) $(autoksyms_h) \
1109 include/generated/utsrelease.h
1112 archprepare: archheaders archscripts prepare1 scripts
1114 prepare0: archprepare
1115 $(Q)$(MAKE) $(build)=scripts/mod
1116 $(Q)$(MAKE) $(build)=.
1118 # All the preparing..
1119 prepare: prepare0 prepare-objtool
1121 # Support for using generic headers in asm-generic
1122 asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1124 PHONY += asm-generic uapi-asm-generic
1125 asm-generic: uapi-asm-generic
1126 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1127 generic=include/asm-generic
1129 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1130 generic=include/uapi/asm-generic
1132 PHONY += prepare-objtool
1133 prepare-objtool: $(objtool_target)
1134 ifeq ($(SKIP_STACK_VALIDATION),1)
1135 ifdef CONFIG_UNWINDER_ORC
1136 @echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1139 @echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1143 # Generate some files
1144 # ---------------------------------------------------------------------------
1146 # KERNELRELEASE can change from a few different places, meaning version.h
1147 # needs to be updated, so this check is forced on all builds
1150 define filechk_utsrelease.h
1151 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1152 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1155 echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1158 define filechk_version.h
1159 echo \#define LINUX_VERSION_CODE $(shell \
1160 expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1161 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))'
1165 $(call filechk,version.h)
1166 $(Q)rm -f $(old_version_h)
1168 include/generated/utsrelease.h: include/config/kernel.release FORCE
1169 $(call filechk,utsrelease.h)
1173 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1174 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1176 # ---------------------------------------------------------------------------
1179 #Default location for installed headers
1180 export INSTALL_HDR_PATH = $(objtree)/usr
1182 quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1183 cmd_headers_install = \
1184 mkdir -p $(INSTALL_HDR_PATH); \
1185 rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1186 usr/include $(INSTALL_HDR_PATH)
1188 PHONY += headers_install
1189 headers_install: headers
1190 $(call cmd,headers_install)
1192 PHONY += archheaders archscripts
1194 hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1197 headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1198 $(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1199 $(error Headers not exportable for the $(SRCARCH) architecture))
1200 $(Q)$(MAKE) $(hdr-inst)=include/uapi
1201 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1203 PHONY += headers_check
1204 headers_check: headers
1205 $(Q)$(MAKE) $(hdr-inst)=include/uapi HDRCHECK=1
1206 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi HDRCHECK=1
1208 ifdef CONFIG_HEADERS_INSTALL
1212 ifdef CONFIG_HEADERS_CHECK
1216 PHONY += scripts_unifdef
1217 scripts_unifdef: scripts_basic
1218 $(Q)$(MAKE) $(build)=scripts scripts/unifdef
1220 # ---------------------------------------------------------------------------
1225 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1227 PHONY += kselftest-clean
1229 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests clean
1231 PHONY += kselftest-merge
1233 $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1234 $(Q)find $(srctree)/tools/testing/selftests -name config | \
1235 xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1236 +$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1238 # ---------------------------------------------------------------------------
1241 ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1242 dtstree := arch/$(SRCARCH)/boot/dts
1247 %.dtb: prepare3 scripts_dtc
1248 $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1250 PHONY += dtbs dtbs_install dt_binding_check
1251 dtbs dtbs_check: prepare3 scripts_dtc
1252 $(Q)$(MAKE) $(build)=$(dtstree)
1254 dtbs_check: export CHECK_DTBS=1
1255 dtbs_check: dt_binding_check
1258 $(Q)$(MAKE) $(dtbinst)=$(dtstree)
1260 ifdef CONFIG_OF_EARLY_FLATTREE
1266 PHONY += scripts_dtc
1267 scripts_dtc: scripts_basic
1268 $(Q)$(MAKE) $(build)=scripts/dtc
1270 dt_binding_check: scripts_dtc
1271 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1273 # ---------------------------------------------------------------------------
1276 ifdef CONFIG_MODULES
1278 # By default, build modules as well
1284 # A module can be listed more than once in obj-m resulting in
1285 # duplicate lines in modules.order files. Those are removed
1286 # using awk while concatenating to the final file.
1289 modules: $(if $(KBUILD_BUILTIN),vmlinux) modules.order modules.builtin
1290 @$(kecho) ' Building modules, stage 2.';
1291 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1292 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh
1294 modules.order: $(vmlinux-dirs)
1295 $(Q)$(AWK) '!x[$$0]++' $(addsuffix /$@, $(vmlinux-dirs)) > $@
1297 modbuiltin-dirs := $(addprefix _modbuiltin_, $(vmlinux-dirs))
1299 modules.builtin: $(modbuiltin-dirs)
1300 $(Q)$(AWK) '!x[$$0]++' $(addsuffix /$@, $(vmlinux-dirs)) > $@
1302 PHONY += $(modbuiltin-dirs)
1303 # tristate.conf is not included from this Makefile. Add it as a prerequisite
1304 # here to make it self-healing in case somebody accidentally removes it.
1305 $(modbuiltin-dirs): include/config/tristate.conf
1306 $(Q)$(MAKE) $(modbuiltin)=$(patsubst _modbuiltin_%,%,$@)
1308 # Target to prepare building external modules
1309 PHONY += modules_prepare
1310 modules_prepare: prepare
1312 # Target to install modules
1313 PHONY += modules_install
1314 modules_install: _modinst_ _modinst_post
1318 @rm -rf $(MODLIB)/kernel
1319 @rm -f $(MODLIB)/source
1320 @mkdir -p $(MODLIB)/kernel
1321 @ln -s $(abspath $(srctree)) $(MODLIB)/source
1322 @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
1323 rm -f $(MODLIB)/build ; \
1324 ln -s $(CURDIR) $(MODLIB)/build ; \
1326 @cp -f $(objtree)/modules.order $(MODLIB)/
1327 @cp -f $(objtree)/modules.builtin $(MODLIB)/
1328 @cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
1329 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1331 # This depmod is only for convenience to give the initial
1332 # boot a modules.dep even before / is mounted read-write. However the
1333 # boot script depmod is the master version.
1334 PHONY += _modinst_post
1335 _modinst_post: _modinst_
1338 ifeq ($(CONFIG_MODULE_SIG), y)
1339 PHONY += modules_sign
1341 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1344 else # CONFIG_MODULES
1346 # Modules not configured
1347 # ---------------------------------------------------------------------------
1349 PHONY += modules modules_install
1350 modules modules_install:
1352 @echo >&2 "The present kernel configuration has modules disabled."
1353 @echo >&2 "Type 'make config' and enable loadable module support."
1354 @echo >&2 "Then build a kernel with module support enabled."
1358 endif # CONFIG_MODULES
1361 # Cleaning is done on three levels.
1362 # make clean Delete most generated files
1363 # Leave enough to build external modules
1364 # make mrproper Delete the current configuration, and all generated files
1365 # make distclean Remove editor backup files, patch leftover files and the like
1367 # Directories & files removed with 'make clean'
1368 CLEAN_DIRS += $(MODVERDIR) include/ksym
1369 CLEAN_FILES += modules.builtin.modinfo
1371 # Directories & files removed with 'make mrproper'
1372 MRPROPER_DIRS += include/config usr/include include/generated \
1373 arch/$(SRCARCH)/include/generated .tmp_objdiff
1374 MRPROPER_FILES += .config .config.old .version \
1375 Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS \
1376 signing_key.pem signing_key.priv signing_key.x509 \
1377 x509.genkey extra_certificates signing_key.x509.keyid \
1378 signing_key.x509.signer vmlinux-gdb.py
1380 # clean - Delete most, but leave enough to build external modules
1382 clean: rm-dirs := $(CLEAN_DIRS)
1383 clean: rm-files := $(CLEAN_FILES)
1384 clean-dirs := $(addprefix _clean_, . $(vmlinux-alldirs))
1386 PHONY += $(clean-dirs) clean archclean vmlinuxclean
1388 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1391 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1392 $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1394 clean: archclean vmlinuxclean
1396 # mrproper - Delete all generated files, including .config
1398 mrproper: rm-dirs := $(wildcard $(MRPROPER_DIRS))
1399 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1400 mrproper-dirs := $(addprefix _mrproper_,scripts)
1402 PHONY += $(mrproper-dirs) mrproper
1404 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1406 mrproper: clean $(mrproper-dirs)
1415 @find $(srctree) $(RCS_FIND_IGNORE) \
1416 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1417 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1418 -o -name 'core' \) \
1419 -type f -print | xargs rm -f
1422 # Packaging of the kernel to various formats
1423 # ---------------------------------------------------------------------------
1424 package-dir := scripts/package
1427 $(Q)$(MAKE) $(build)=$(package-dir) $@
1428 %pkg: include/config/kernel.release FORCE
1429 $(Q)$(MAKE) $(build)=$(package-dir) $@
1432 # Brief documentation of the typical targets used
1433 # ---------------------------------------------------------------------------
1435 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1436 boards := $(sort $(notdir $(boards)))
1437 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1438 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1442 @echo 'Cleaning targets:'
1443 @echo ' clean - Remove most generated files but keep the config and'
1444 @echo ' enough build support to build external modules'
1445 @echo ' mrproper - Remove all generated files + config + various backup files'
1446 @echo ' distclean - mrproper + remove editor backup and patch files'
1448 @echo 'Configuration targets:'
1449 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1451 @echo 'Other generic targets:'
1452 @echo ' all - Build all targets marked with [*]'
1453 @echo '* vmlinux - Build the bare kernel'
1454 @echo '* modules - Build all modules'
1455 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1456 @echo ' dir/ - Build all files in dir and below'
1457 @echo ' dir/file.[ois] - Build specified target only'
1458 @echo ' dir/file.ll - Build the LLVM assembly file'
1459 @echo ' (requires compiler support for LLVM assembly generation)'
1460 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1461 @echo ' (requires a recent binutils and recent build (System.map))'
1462 @echo ' dir/file.ko - Build module including final link'
1463 @echo ' modules_prepare - Set up for building external modules'
1464 @echo ' tags/TAGS - Generate tags file for editors'
1465 @echo ' cscope - Generate cscope index'
1466 @echo ' gtags - Generate GNU GLOBAL index'
1467 @echo ' kernelrelease - Output the release version string (use with make -s)'
1468 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1469 @echo ' image_name - Output the image name (use with make -s)'
1470 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1471 echo ' (default: $(INSTALL_HDR_PATH))'; \
1473 @echo 'Static analysers:'
1474 @echo ' checkstack - Generate a list of stack hogs'
1475 @echo ' namespacecheck - Name space analysis on compiled kernel'
1476 @echo ' versioncheck - Sanity check on version.h usage'
1477 @echo ' includecheck - Check for duplicate included header files'
1478 @echo ' export_report - List the usages of all exported symbols'
1479 @echo ' headers_check - Sanity check on exported headers'
1480 @echo ' headerdep - Detect inclusion cycles in headers'
1481 @echo ' coccicheck - Check with Coccinelle'
1483 @echo 'Kernel selftest:'
1484 @echo ' kselftest - Build and run kernel selftest (run as root)'
1485 @echo ' Build, install, and boot kernel before'
1486 @echo ' running kselftest on it'
1487 @echo ' kselftest-clean - Remove all generated kselftest files'
1488 @echo ' kselftest-merge - Merge all the config dependencies of kselftest to existing'
1492 echo 'Devicetree:'; \
1493 echo '* dtbs - Build device tree blobs for enabled boards'; \
1494 echo ' dtbs_install - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1497 @echo 'Userspace tools targets:'
1498 @echo ' use "make tools/help"'
1499 @echo ' or "cd tools; make help"'
1501 @echo 'Kernel packaging:'
1502 @$(MAKE) $(build)=$(package-dir) help
1504 @echo 'Documentation targets:'
1505 @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1507 @echo 'Architecture specific targets ($(SRCARCH)):'
1508 @$(if $(archhelp),$(archhelp),\
1509 echo ' No architecture specific help defined for $(SRCARCH)')
1512 $(foreach b, $(boards), \
1513 printf " %-24s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1515 @$(if $(board-dirs), \
1516 $(foreach b, $(board-dirs), \
1517 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1518 printf " %-16s - Show all of the above\\n" help-boards; \
1521 @echo ' make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1522 @echo ' make V=2 [targets] 2 => give reason for rebuild of target'
1523 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1524 @echo ' make C=1 [targets] Check re-compiled c source with $$CHECK (sparse by default)'
1525 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1526 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1527 @echo ' make W=n [targets] Enable extra gcc checks, n=1,2,3 where'
1528 @echo ' 1: warnings which may be relevant and do not occur too often'
1529 @echo ' 2: warnings which occur quite often but may still be relevant'
1530 @echo ' 3: more obscure warnings, can most likely be ignored'
1531 @echo ' Multiple levels can be combined with W=12 or W=123'
1533 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1534 @echo 'For further info see the ./README file'
1537 help-board-dirs := $(addprefix help-,$(board-dirs))
1539 help-boards: $(help-board-dirs)
1541 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1543 $(help-board-dirs): help-%:
1544 @echo 'Architecture specific targets ($(SRCARCH) $*):'
1545 @$(if $(boards-per-dir), \
1546 $(foreach b, $(boards-per-dir), \
1547 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1551 # Documentation targets
1552 # ---------------------------------------------------------------------------
1553 DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1554 linkcheckdocs dochelp refcheckdocs
1555 PHONY += $(DOC_TARGETS)
1556 $(DOC_TARGETS): scripts_basic FORCE
1557 $(Q)$(MAKE) $(build)=Documentation $@
1560 # ---------------------------------------------------------------------------
1562 PHONY += scripts_gdb
1563 scripts_gdb: prepare0
1564 $(Q)$(MAKE) $(build)=scripts/gdb
1565 $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1567 ifdef CONFIG_GDB_SCRIPTS
1571 else # KBUILD_EXTMOD
1574 # External module support.
1575 # When building external modules the kernel used as basis is considered
1576 # read-only, and no consistency checks are made and the make
1577 # system is not used on the basis kernel. If updates are required
1578 # in the basis kernel ordinary make commands (without M=...) must
1581 # The following are the only valid targets when building external
1583 # make M=dir clean Delete all automatically generated files
1584 # make M=dir modules Make all modules in specified dir
1585 # make M=dir Same as 'make M=dir modules'
1586 # make M=dir modules_install
1587 # Install the modules built in the module directory
1588 # Assumes install directory is already created
1590 # We are always building modules
1593 PHONY += $(objtree)/Module.symvers
1594 $(objtree)/Module.symvers:
1595 @test -e $(objtree)/Module.symvers || ( \
1597 echo " WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1598 echo " is missing; modules will have no dependencies and modversions."; \
1601 module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
1602 PHONY += $(module-dirs) modules
1603 $(module-dirs): prepare $(objtree)/Module.symvers
1604 $(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@)
1606 modules: $(module-dirs)
1607 @$(kecho) ' Building modules, stage 2.';
1608 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1610 PHONY += modules_install
1611 modules_install: _emodinst_ _emodinst_post
1613 install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1616 $(Q)mkdir -p $(MODLIB)/$(install-dir)
1617 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1619 PHONY += _emodinst_post
1620 _emodinst_post: _emodinst_
1623 clean-dirs := $(addprefix _clean_,$(KBUILD_EXTMOD))
1625 PHONY += $(clean-dirs) clean
1627 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1629 clean: rm-dirs := $(MODVERDIR)
1630 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers
1634 @echo ' Building external modules.'
1635 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1637 @echo ' modules - default target, build the module(s)'
1638 @echo ' modules_install - install the module'
1639 @echo ' clean - remove generated files in module directory only'
1645 endif # KBUILD_EXTMOD
1647 clean: $(clean-dirs)
1650 @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1651 \( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1653 -o -name '*.dtb' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1654 -o -name '*.dwo' -o -name '*.lst' \
1656 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1657 -o -name '*.hdrtest.c' \
1658 -o -name '*.lex.c' -o -name '*.tab.[ch]' \
1659 -o -name '*.asn1.[ch]' \
1660 -o -name '*.symtypes' -o -name 'modules.order' \
1661 -o -name modules.builtin -o -name '.tmp_*.o.*' \
1662 -o -name '*.c.[012]*.*' \
1664 -o -name '*.gcno' \) -type f -print | xargs rm -f
1666 # Generate tags for editors
1667 # ---------------------------------------------------------------------------
1668 quiet_cmd_tags = GEN $@
1669 cmd_tags = $(CONFIG_SHELL) $(srctree)/scripts/tags.sh $@
1671 tags TAGS cscope gtags: FORCE
1674 # Scripts to check various things for consistency
1675 # ---------------------------------------------------------------------------
1677 PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1680 find $(srctree)/* $(RCS_FIND_IGNORE) \
1681 -name '*.[hcS]' -type f -print | sort \
1682 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1685 find $(srctree)/* $(RCS_FIND_IGNORE) \
1686 -name '*.[hcS]' -type f -print | sort \
1687 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1690 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/$@
1693 $(PERL) $(srctree)/scripts/namespace.pl
1696 $(PERL) $(srctree)/scripts/export_report.pl
1698 PHONY += checkstack kernelrelease kernelversion image_name
1700 # UML needs a little special treatment here. It wants to use the host
1701 # toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
1702 # else wants $(ARCH), including people doing cross-builds, which means
1703 # that $(SUBARCH) doesn't work here.
1705 CHECKSTACK_ARCH := $(SUBARCH)
1707 CHECKSTACK_ARCH := $(ARCH)
1710 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1711 $(PERL) $(src)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1714 @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1717 @echo $(KERNELVERSION)
1720 @echo $(KBUILD_IMAGE)
1722 # Clear a bunch of variables before executing the submake
1724 ifeq ($(quiet),silent_)
1729 $(Q)mkdir -p $(objtree)/tools
1730 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(src)/tools/
1733 $(Q)mkdir -p $(objtree)/tools
1734 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(src)/tools/ $*
1737 # ---------------------------------------------------------------------------
1738 # Single targets are compatible with:
1739 # - build with mixed source and output
1740 # - build with separate output dir 'make O=...'
1741 # - external modules
1743 # target-dir => where to store outputfile
1744 # build-dir => directory in kernel source tree to use
1746 build-target = $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD)/)$@
1747 build-dir = $(patsubst %/,%,$(dir $(build-target)))
1750 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1752 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1753 %.lst: prepare FORCE
1754 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1756 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1758 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1759 %.symtypes: prepare FORCE
1760 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1762 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1769 $(Q)$(MAKE) KBUILD_MODULES=1 $(build)=$(build-dir)
1771 # FIXME Should go into a make.lib or something
1772 # ===========================================================================
1774 quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN $(wildcard $(rm-dirs)))
1775 cmd_rmdirs = rm -rf $(rm-dirs)
1777 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
1778 cmd_rmfiles = rm -f $(rm-files)
1780 # Run depmod only if we have System.map and depmod is executable
1781 quiet_cmd_depmod = DEPMOD $(KERNELRELEASE)
1782 cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1785 # Create temporary dir for module support files
1786 # clean it up only when building all modules
1787 cmd_crmodverdir = $(Q)mkdir -p $(MODVERDIR) \
1788 $(if $(KBUILD_MODULES),; rm -f $(MODVERDIR)/*)
1790 # read saved command lines for existing targets
1791 existing-targets := $(wildcard $(sort $(targets)))
1793 -include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
1795 endif # ifeq ($(config-targets),1)
1796 endif # ifeq ($(mixed-targets),1)
1797 endif # need-sub-make
1802 # Declare the contents of the PHONY variable as phony. We keep that
1803 # information in a variable so we can use it in if_changed and friends.