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 supports saving output files in a separate directory.
100 # To locate output files in a separate directory two syntaxes are supported.
101 # In both cases the working directory must be the root of the kernel src.
103 # Use "make O=dir/to/store/output/files/"
105 # 2) Set KBUILD_OUTPUT
106 # Set the environment variable KBUILD_OUTPUT to point to the directory
107 # where the output files shall be placed.
108 # export KBUILD_OUTPUT=dir/to/store/output/files/
111 # The O= assignment takes precedence over the KBUILD_OUTPUT environment
114 # KBUILD_SRC is not intended to be used by the regular user (for now),
115 # it is set on invocation of make with KBUILD_OUTPUT or O= specified.
117 # OK, Make called in directory where kernel src resides
118 # Do we want to locate output files in a separate directory?
119 ifeq ("$(origin O)", "command line")
120 KBUILD_OUTPUT := $(O)
123 ifneq ($(words $(subst :, ,$(CURDIR))), 1)
124 $(error main directory cannot contain spaces nor colons)
127 ifneq ($(KBUILD_OUTPUT),)
128 # check that the output directory actually exists
129 saved-output := $(KBUILD_OUTPUT)
130 KBUILD_OUTPUT := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) \
132 $(if $(KBUILD_OUTPUT),, \
133 $(error failed to create output directory "$(saved-output)"))
135 # Look for make include files relative to root of kernel src
137 # This does not become effective immediately because MAKEFLAGS is re-parsed
138 # once after the Makefile is read. It is OK since we are going to invoke
140 MAKEFLAGS += --include-dir=$(CURDIR)
145 # Do not print "Entering directory ..." at all for in-tree build.
146 MAKEFLAGS += --no-print-directory
148 endif # ifneq ($(KBUILD_OUTPUT),)
150 ifneq ($(filter 3.%,$(MAKE_VERSION)),)
151 # 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
152 # We need to invoke sub-make to avoid implicit rules in the top Makefile.
154 # Cancel implicit rules for this Makefile.
155 $(lastword $(MAKEFILE_LIST)): ;
158 export sub_make_done := 1
160 ifeq ($(need-sub-make),1)
162 PHONY += $(MAKECMDGOALS) sub-make
164 $(filter-out _all sub-make $(CURDIR)/Makefile, $(MAKECMDGOALS)) _all: sub-make
167 # Invoke a second make in the output directory, passing relevant variables
170 $(if $(KBUILD_OUTPUT),-C $(KBUILD_OUTPUT) KBUILD_SRC=$(CURDIR)) \
171 -f $(CURDIR)/Makefile $(filter-out _all sub-make,$(MAKECMDGOALS))
173 endif # need-sub-make
174 endif # sub_make_done
176 # We process the rest of the Makefile if this is the final invocation of make
177 ifeq ($(need-sub-make),)
179 # Do not print "Entering directory ...",
180 # but we want to display it when entering to the output directory
181 # so that IDEs/editors are able to understand relative filenames.
182 MAKEFLAGS += --no-print-directory
184 # Call a source code checker (by default, "sparse") as part of the
187 # Use 'make C=1' to enable checking of only re-compiled files.
188 # Use 'make C=2' to enable checking of *all* source files, regardless
189 # of whether they are re-compiled or not.
191 # See the file "Documentation/dev-tools/sparse.rst" for more details,
192 # including where to get the "sparse" utility.
194 ifeq ("$(origin C)", "command line")
195 KBUILD_CHECKSRC = $(C)
197 ifndef KBUILD_CHECKSRC
201 # Use make M=dir to specify directory of external module to build
202 # Old syntax make ... SUBDIRS=$PWD is still supported
203 # Setting the environment variable KBUILD_EXTMOD take precedence
205 $(warning ================= WARNING ================)
206 $(warning 'SUBDIRS' will be removed after Linux 5.3)
207 $(warning Please use 'M=' or 'KBUILD_EXTMOD' instead)
208 $(warning ==========================================)
209 KBUILD_EXTMOD ?= $(SUBDIRS)
212 ifeq ("$(origin M)", "command line")
213 KBUILD_EXTMOD := $(M)
216 ifeq ($(KBUILD_SRC),)
217 # building in the source tree
220 ifeq ($(KBUILD_SRC)/,$(dir $(CURDIR)))
221 # building in a subdirectory of the source tree
224 srctree := $(KBUILD_SRC)
228 export KBUILD_CHECKSRC KBUILD_EXTMOD KBUILD_SRC
236 export srctree objtree VPATH
238 # To make sure we do not include .config for any of the *config targets
239 # catch them early, and hand them over to scripts/kconfig/Makefile
240 # It is allowed to specify more targets when calling make, including
241 # mixing *config targets and build targets.
242 # For example 'make oldconfig all'.
243 # Detect when mixed targets is specified, and make a second invocation
244 # of make so .config is not included in this case either (for *config).
246 version_h := include/generated/uapi/linux/version.h
247 old_version_h := include/linux/version.h
249 clean-targets := %clean mrproper cleandocs
250 no-dot-config-targets := $(clean-targets) \
251 cscope gtags TAGS tags help% %docs check% coccicheck \
252 $(version_h) headers_% archheaders archscripts \
253 %asm-generic kernelversion %src-pkg
254 no-sync-config-targets := $(no-dot-config-targets) install %install \
262 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
263 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
268 ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
269 ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
274 ifneq ($(KBUILD_EXTMOD),)
278 ifeq ($(KBUILD_EXTMOD),)
279 ifneq ($(filter config %config,$(MAKECMDGOALS)),)
281 ifneq ($(words $(MAKECMDGOALS)),1)
287 # For "make -j clean all", "make -j mrproper defconfig all", etc.
288 ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
289 ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
294 # install and modules_install need also be processed one by one
295 ifneq ($(filter install,$(MAKECMDGOALS)),)
296 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
301 ifeq ($(mixed-targets),1)
302 # ===========================================================================
303 # We're called with mixed targets (*config and build targets).
304 # Handle them one by one.
306 PHONY += $(MAKECMDGOALS) __build_one_by_one
308 $(filter-out __build_one_by_one, $(MAKECMDGOALS)): __build_one_by_one
313 for i in $(MAKECMDGOALS); do \
314 $(MAKE) -f $(srctree)/Makefile $$i; \
319 include scripts/Kbuild.include
321 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
322 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
323 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
324 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
326 include scripts/subarch.include
328 # Cross compiling and selecting different set of gcc/bin-utils
329 # ---------------------------------------------------------------------------
331 # When performing cross compilation for other architectures ARCH shall be set
332 # to the target architecture. (See arch/* for the possibilities).
333 # ARCH can be set during invocation of make:
335 # Another way is to have ARCH set in the environment.
336 # The default ARCH is the host where make is executed.
338 # CROSS_COMPILE specify the prefix used for all executables used
339 # during compilation. Only gcc and related bin-utils executables
340 # are prefixed with $(CROSS_COMPILE).
341 # CROSS_COMPILE can be set on the command line
342 # make CROSS_COMPILE=ia64-linux-
343 # Alternatively CROSS_COMPILE can be set in the environment.
344 # Default value for CROSS_COMPILE is not to prefix executables
345 # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
348 # Architecture as present in compile.h
349 UTS_MACHINE := $(ARCH)
352 # Additional ARCH settings for x86
356 ifeq ($(ARCH),x86_64)
360 # Additional ARCH settings for sparc
361 ifeq ($(ARCH),sparc32)
364 ifeq ($(ARCH),sparc64)
368 # Additional ARCH settings for sh
373 KCONFIG_CONFIG ?= .config
374 export KCONFIG_CONFIG
376 # SHELL used by kbuild
377 CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
378 else if [ -x /bin/bash ]; then echo /bin/bash; \
379 else echo sh; fi ; fi)
381 HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
382 HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
383 HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
387 KBUILD_HOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 \
388 -fomit-frame-pointer -std=gnu89 $(HOST_LFS_CFLAGS) \
390 KBUILD_HOSTCXXFLAGS := -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
391 KBUILD_HOSTLDFLAGS := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
392 KBUILD_HOSTLDLIBS := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
394 # Make variables (CC, etc...)
395 AS = $(CROSS_COMPILE)as
396 LD = $(CROSS_COMPILE)ld
397 CC = $(CROSS_COMPILE)gcc
399 AR = $(CROSS_COMPILE)ar
400 NM = $(CROSS_COMPILE)nm
401 STRIP = $(CROSS_COMPILE)strip
402 OBJCOPY = $(CROSS_COMPILE)objcopy
403 OBJDUMP = $(CROSS_COMPILE)objdump
407 INSTALLKERNEL := installkernel
408 DEPMOD = /sbin/depmod
415 CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
416 -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
425 # Use USERINCLUDE when you must reference the UAPI directories only.
427 -I$(srctree)/arch/$(SRCARCH)/include/uapi \
428 -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
429 -I$(srctree)/include/uapi \
430 -I$(objtree)/include/generated/uapi \
431 -include $(srctree)/include/linux/kconfig.h
433 # Use LINUXINCLUDE when you must reference the include/ directory.
434 # Needed to be compatible with the O= option
436 -I$(srctree)/arch/$(SRCARCH)/include \
437 -I$(objtree)/arch/$(SRCARCH)/include/generated \
438 $(if $(KBUILD_SRC), -I$(srctree)/include) \
439 -I$(objtree)/include \
442 KBUILD_AFLAGS := -D__ASSEMBLY__ -fno-PIE
443 KBUILD_CFLAGS := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
444 -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
445 -Werror=implicit-function-declaration -Werror=implicit-int \
446 -Wno-format-security \
448 KBUILD_CPPFLAGS := -D__KERNEL__
449 KBUILD_AFLAGS_KERNEL :=
450 KBUILD_CFLAGS_KERNEL :=
451 KBUILD_AFLAGS_MODULE := -DMODULE
452 KBUILD_CFLAGS_MODULE := -DMODULE
453 KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
455 GCC_PLUGINS_CFLAGS :=
457 export ARCH SRCARCH CONFIG_SHELL HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE AS LD CC
458 export CPP AR NM STRIP OBJCOPY OBJDUMP KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS
459 export MAKE LEX YACC AWK INSTALLKERNEL PERL PYTHON PYTHON2 PYTHON3 UTS_MACHINE
460 export HOSTCXX KBUILD_HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
462 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
463 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
464 export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN
465 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
466 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
467 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
468 export KBUILD_ARFLAGS
470 # When compiling out-of-tree modules, put MODVERDIR in the module
471 # tree rather than in the kernel tree. The kernel tree might
473 export MODVERDIR := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_versions
475 # Files to ignore in find ... statements
477 export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o \
478 -name CVS -o -name .pc -o -name .hg -o -name .git \) \
480 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
481 --exclude CVS --exclude .pc --exclude .hg --exclude .git
483 # ===========================================================================
484 # Rules shared between *config targets and build targets
486 # Basic helpers built in scripts/basic/
487 PHONY += scripts_basic
489 $(Q)$(MAKE) $(build)=scripts/basic
490 $(Q)rm -f .tmp_quiet_recordmcount
492 PHONY += outputmakefile
493 # outputmakefile generates a Makefile in the output directory, if using a
494 # separate output directory. This allows convenient use of make in the
496 # At the same time when output Makefile generated, generate .gitignore to
497 # ignore whole output directory
499 ifneq ($(KBUILD_SRC),)
500 $(Q)ln -fsn $(srctree) source
501 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile $(srctree)
502 $(Q)test -e .gitignore || \
503 { echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
506 ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),)
507 ifneq ($(CROSS_COMPILE),)
508 CLANG_FLAGS := --target=$(notdir $(CROSS_COMPILE:%-=%))
509 GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
510 CLANG_FLAGS += --prefix=$(GCC_TOOLCHAIN_DIR)
511 GCC_TOOLCHAIN := $(realpath $(GCC_TOOLCHAIN_DIR)/..)
513 ifneq ($(GCC_TOOLCHAIN),)
514 CLANG_FLAGS += --gcc-toolchain=$(GCC_TOOLCHAIN)
516 CLANG_FLAGS += -no-integrated-as
517 KBUILD_CFLAGS += $(CLANG_FLAGS)
518 KBUILD_AFLAGS += $(CLANG_FLAGS)
522 RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
523 RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
524 RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
525 RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
526 RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
527 RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
528 export RETPOLINE_CFLAGS
529 export RETPOLINE_VDSO_CFLAGS
531 # The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
532 # Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
533 # CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
534 # and from include/config/auto.conf.cmd to detect the compiler upgrade.
535 CC_VERSION_TEXT = $(shell $(CC) --version | head -n 1)
537 ifeq ($(config-targets),1)
538 # ===========================================================================
539 # *config targets only - make sure prerequisites are updated, and descend
540 # in scripts/kconfig to make the *config target
542 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
543 # KBUILD_DEFCONFIG may point out an alternative default configuration
544 # used for 'make defconfig'
545 include arch/$(SRCARCH)/Makefile
546 export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
548 config: scripts_basic outputmakefile FORCE
549 $(Q)$(MAKE) $(build)=scripts/kconfig $@
551 %config: scripts_basic outputmakefile FORCE
552 $(Q)$(MAKE) $(build)=scripts/kconfig $@
555 # ===========================================================================
556 # Build targets only - this includes vmlinux, arch specific targets, clean
557 # targets and others. In general all targets except *config targets.
559 # If building an external module we do not care about the all: rule
560 # but instead _all depend on modules
562 ifeq ($(KBUILD_EXTMOD),)
568 # Decide whether to build built-in, modular, or both.
569 # Normally, just do built-in.
574 # If we have only "make modules", don't compile built-in objects.
575 # When we're building modules with modversions, we need to consider
576 # the built-in objects during the descend as well, in order to
577 # make sure the checksums are up to date before we record them.
579 ifeq ($(MAKECMDGOALS),modules)
580 KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
583 # If we have "make <whatever> modules", compile modules
584 # in addition to whatever we do anyway.
585 # Just "make" or "make all" shall build modules as well
587 ifneq ($(filter all _all modules,$(MAKECMDGOALS)),)
591 ifeq ($(MAKECMDGOALS),)
595 export KBUILD_MODULES KBUILD_BUILTIN
597 ifeq ($(KBUILD_EXTMOD),)
598 # Objects we will link into vmlinux / subdirs we need to visit
600 drivers-y := drivers/ sound/
605 endif # KBUILD_EXTMOD
607 ifeq ($(dot-config),1)
608 include include/config/auto.conf
611 # The all: target is the default when no target is given on the
613 # This allow a user to issue only 'make' to build a kernel including modules
614 # Defaults to vmlinux, but the arch makefile usually adds further targets
617 CFLAGS_GCOV := -fprofile-arcs -ftest-coverage \
618 $(call cc-option,-fno-tree-loop-im) \
619 $(call cc-disable-warning,maybe-uninitialized,)
622 # The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
623 ifdef CONFIG_FUNCTION_TRACER
624 CC_FLAGS_FTRACE := -pg
627 # The arch Makefile can set ARCH_{CPP,A,C}FLAGS to override the default
628 # values of the respective KBUILD_* variables
632 include arch/$(SRCARCH)/Makefile
634 ifeq ($(dot-config),1)
635 ifeq ($(may-sync-config),1)
636 # Read in dependencies to all Kconfig* files, make sure to run syncconfig if
637 # changes are detected. This should be included after arch/$(SRCARCH)/Makefile
638 # because some architectures define CROSS_COMPILE there.
639 -include include/config/auto.conf.cmd
643 @echo >&2 '*** Configuration file "$@" not found!'
645 @echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
646 @echo >&2 '*** "make menuconfig" or "make xconfig").'
650 # The actual configuration files used during the build are stored in
651 # include/generated/ and include/config/. Update them if .config is newer than
652 # include/config/auto.conf (which mirrors .config).
654 # This exploits the 'multi-target pattern rule' trick.
655 # The syncconfig should be executed only once to make all the targets.
656 %/auto.conf %/auto.conf.cmd %/tristate.conf: $(KCONFIG_CONFIG)
657 $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
659 # External modules and some install targets need include/generated/autoconf.h
660 # and include/config/auto.conf but do not care if they are up-to-date.
661 # Use auto.conf to trigger the test
662 PHONY += include/config/auto.conf
664 include/config/auto.conf:
665 $(Q)test -e include/generated/autoconf.h -a -e $@ || ( \
667 echo >&2 " ERROR: Kernel configuration is invalid."; \
668 echo >&2 " include/generated/autoconf.h or $@ are missing.";\
669 echo >&2 " Run 'make oldconfig && make prepare' on kernel src to fix it."; \
673 endif # may-sync-config
674 endif # $(dot-config)
676 KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,)
677 KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,)
678 KBUILD_CFLAGS += $(call cc-disable-warning, format-truncation)
679 KBUILD_CFLAGS += $(call cc-disable-warning, format-overflow)
680 KBUILD_CFLAGS += $(call cc-disable-warning, int-in-bool-context)
681 KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
683 ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
689 ifdef CONFIG_CC_DISABLE_WARN_MAYBE_UNINITIALIZED
690 KBUILD_CFLAGS += -Wno-maybe-uninitialized
693 # Tell gcc to never replace conditional load with a non-conditional one
694 KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
696 include scripts/Makefile.kcov
697 include scripts/Makefile.gcc-plugins
699 ifdef CONFIG_READABLE_ASM
700 # Disable optimizations that make assembler listings hard to read.
701 # reorder blocks reorders the control in the function
702 # ipa clone creates specialized cloned functions
703 # partial inlining inlines only parts of functions
704 KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
705 $(call cc-option,-fno-ipa-cp-clone,) \
706 $(call cc-option,-fno-partial-inlining)
709 ifneq ($(CONFIG_FRAME_WARN),0)
710 KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
713 stackp-flags-$(CONFIG_CC_HAS_STACKPROTECTOR_NONE) := -fno-stack-protector
714 stackp-flags-$(CONFIG_STACKPROTECTOR) := -fstack-protector
715 stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG) := -fstack-protector-strong
717 KBUILD_CFLAGS += $(stackp-flags-y)
719 ifdef CONFIG_CC_IS_CLANG
720 KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
721 KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier)
722 KBUILD_CFLAGS += $(call cc-disable-warning, gnu)
723 # Quiet clang warning: comparison of unsigned expression < 0 is always false
724 KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare)
725 # CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
726 # source of a reference will be _MergedGlobals and not on of the whitelisted names.
727 # See modpost pattern 2
728 KBUILD_CFLAGS += $(call cc-option, -mno-global-merge,)
729 KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior)
732 # These warnings generated too much noise in a regular build.
733 # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
734 KBUILD_CFLAGS += -Wno-unused-but-set-variable
737 KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
738 ifdef CONFIG_FRAME_POINTER
739 KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
741 # Some targets (ARM with Thumb2, for example), can't be built with frame
742 # pointers. For those, we don't have FUNCTION_TRACER automatically
743 # select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
744 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
745 # -fomit-frame-pointer with FUNCTION_TRACER.
746 ifndef CONFIG_FUNCTION_TRACER
747 KBUILD_CFLAGS += -fomit-frame-pointer
751 DEBUG_CFLAGS := $(call cc-option, -fno-var-tracking-assignments)
753 ifdef CONFIG_DEBUG_INFO
754 ifdef CONFIG_DEBUG_INFO_SPLIT
755 DEBUG_CFLAGS += -gsplit-dwarf
759 KBUILD_AFLAGS += -Wa,-gdwarf-2
761 ifdef CONFIG_DEBUG_INFO_DWARF4
762 DEBUG_CFLAGS += -gdwarf-4
765 ifdef CONFIG_DEBUG_INFO_REDUCED
766 DEBUG_CFLAGS += $(call cc-option, -femit-struct-debug-baseonly) \
767 $(call cc-option,-fno-var-tracking)
770 KBUILD_CFLAGS += $(DEBUG_CFLAGS)
773 ifdef CONFIG_FUNCTION_TRACER
774 ifdef CONFIG_FTRACE_MCOUNT_RECORD
775 # gcc 5 supports generating the mcount tables directly
776 ifeq ($(call cc-option-yn,-mrecord-mcount),y)
777 CC_FLAGS_FTRACE += -mrecord-mcount
778 export CC_USING_RECORD_MCOUNT := 1
780 ifdef CONFIG_HAVE_NOP_MCOUNT
781 ifeq ($(call cc-option-yn, -mnop-mcount),y)
782 CC_FLAGS_FTRACE += -mnop-mcount
783 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
787 ifdef CONFIG_HAVE_FENTRY
788 ifeq ($(call cc-option-yn, -mfentry),y)
789 CC_FLAGS_FTRACE += -mfentry
790 CC_FLAGS_USING += -DCC_USING_FENTRY
793 export CC_FLAGS_FTRACE
794 KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
795 KBUILD_AFLAGS += $(CC_FLAGS_USING)
796 ifdef CONFIG_DYNAMIC_FTRACE
797 ifdef CONFIG_HAVE_C_RECORDMCOUNT
798 BUILD_C_RECORDMCOUNT := y
799 export BUILD_C_RECORDMCOUNT
804 # We trigger additional mismatches with less inlining
805 ifdef CONFIG_DEBUG_SECTION_MISMATCH
806 KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
809 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
810 KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
811 LDFLAGS_vmlinux += --gc-sections
814 ifdef CONFIG_LIVEPATCH
815 KBUILD_CFLAGS += $(call cc-option, -flive-patching=inline-clone)
818 # arch Makefile may override CC so keep this after arch Makefile is included
819 NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
821 # warn about C99 declaration after statement
822 KBUILD_CFLAGS += -Wdeclaration-after-statement
824 # Variable Length Arrays (VLAs) should not be used anywhere in the kernel
825 KBUILD_CFLAGS += $(call cc-option,-Wvla)
827 # disable pointer signed / unsigned warnings in gcc 4.0
828 KBUILD_CFLAGS += -Wno-pointer-sign
830 # disable stringop warnings in gcc 8+
831 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
833 # disable invalid "can't wrap" optimizations for signed / pointers
834 KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow)
836 # clang sets -fmerge-all-constants by default as optimization, but this
837 # is non-conforming behavior for C and in fact breaks the kernel, so we
838 # need to disable it here generally.
839 KBUILD_CFLAGS += $(call cc-option,-fno-merge-all-constants)
841 # for gcc -fno-merge-all-constants disables everything, but it is fine
842 # to have actual conforming behavior enabled.
843 KBUILD_CFLAGS += $(call cc-option,-fmerge-constants)
845 # Make sure -fstack-check isn't enabled (like gentoo apparently did)
846 KBUILD_CFLAGS += $(call cc-option,-fno-stack-check,)
848 # conserve stack if available
849 KBUILD_CFLAGS += $(call cc-option,-fconserve-stack)
851 # Prohibit date/time macros, which would make the build non-deterministic
852 KBUILD_CFLAGS += $(call cc-option,-Werror=date-time)
854 # enforce correct pointer usage
855 KBUILD_CFLAGS += $(call cc-option,-Werror=incompatible-pointer-types)
857 # Require designated initializers for all marked structures
858 KBUILD_CFLAGS += $(call cc-option,-Werror=designated-init)
860 # change __FILE__ to the relative path from the srctree
861 KBUILD_CFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
863 # use the deterministic mode of AR if available
864 KBUILD_ARFLAGS := $(call ar-option,D)
866 include scripts/Makefile.kasan
867 include scripts/Makefile.extrawarn
868 include scripts/Makefile.ubsan
870 # Add any arch overrides and user supplied CPPFLAGS, AFLAGS and CFLAGS as the
872 KBUILD_CPPFLAGS += $(ARCH_CPPFLAGS) $(KCPPFLAGS)
873 KBUILD_AFLAGS += $(ARCH_AFLAGS) $(KAFLAGS)
874 KBUILD_CFLAGS += $(ARCH_CFLAGS) $(KCFLAGS)
876 # Use --build-id when available.
877 LDFLAGS_BUILD_ID := $(call ld-option, --build-id)
878 KBUILD_LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID)
879 LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)
881 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
882 LDFLAGS_vmlinux += $(call ld-option, -X,)
885 # insure the checker run with the right endianness
886 CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
888 # the checker needs the correct machine size
889 CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
891 # Default kernel image to build when no specific target is given.
892 # KBUILD_IMAGE may be overruled on the command line or
893 # set in the environment
894 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
896 export KBUILD_IMAGE ?= vmlinux
899 # INSTALL_PATH specifies where to place the updated kernel and system map
900 # images. Default is /boot, but you can set it to other values
901 export INSTALL_PATH ?= /boot
904 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
905 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
906 # an argument if needed. Otherwise it defaults to the kernel install path
908 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
911 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
912 # relocations required by build roots. This is not defined in the
913 # makefile but the argument can be passed to make if needed.
916 MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
920 # INSTALL_MOD_STRIP, if defined, will cause modules to be
921 # stripped after they are installed. If INSTALL_MOD_STRIP is '1', then
922 # the default option --strip-debug will be used. Otherwise,
923 # INSTALL_MOD_STRIP value will be used as the options to the strip command.
925 ifdef INSTALL_MOD_STRIP
926 ifeq ($(INSTALL_MOD_STRIP),1)
927 mod_strip_cmd = $(STRIP) --strip-debug
929 mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
930 endif # INSTALL_MOD_STRIP=1
933 endif # INSTALL_MOD_STRIP
936 # CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
937 # after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
938 # or CONFIG_MODULE_COMPRESS_XZ.
940 mod_compress_cmd = true
941 ifdef CONFIG_MODULE_COMPRESS
942 ifdef CONFIG_MODULE_COMPRESS_GZIP
943 mod_compress_cmd = gzip -n -f
944 endif # CONFIG_MODULE_COMPRESS_GZIP
945 ifdef CONFIG_MODULE_COMPRESS_XZ
946 mod_compress_cmd = xz -f
947 endif # CONFIG_MODULE_COMPRESS_XZ
948 endif # CONFIG_MODULE_COMPRESS
949 export mod_compress_cmd
951 ifdef CONFIG_MODULE_SIG_ALL
952 $(eval $(call config_filename,MODULE_SIG_KEY))
954 mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
960 HOST_LIBELF_LIBS = $(shell pkg-config libelf --libs 2>/dev/null || echo -lelf)
962 ifdef CONFIG_STACK_VALIDATION
963 has_libelf := $(call try-run,\
964 echo "int main() {}" | $(HOSTCC) -xc -o /dev/null $(HOST_LIBELF_LIBS) -,1,0)
965 ifeq ($(has_libelf),1)
966 objtool_target := tools/objtool FORCE
968 SKIP_STACK_VALIDATION := 1
969 export SKIP_STACK_VALIDATION
975 ifeq ($(KBUILD_EXTMOD),)
976 core-y += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
978 vmlinux-dirs := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
979 $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
980 $(net-y) $(net-m) $(libs-y) $(libs-m) $(virt-y)))
982 vmlinux-alldirs := $(sort $(vmlinux-dirs) $(patsubst %/,%,$(filter %/, \
983 $(init-) $(core-) $(drivers-) $(net-) $(libs-) $(virt-))))
985 init-y := $(patsubst %/, %/built-in.a, $(init-y))
986 core-y := $(patsubst %/, %/built-in.a, $(core-y))
987 drivers-y := $(patsubst %/, %/built-in.a, $(drivers-y))
988 net-y := $(patsubst %/, %/built-in.a, $(net-y))
989 libs-y1 := $(patsubst %/, %/lib.a, $(libs-y))
990 libs-y2 := $(patsubst %/, %/built-in.a, $(filter-out %.a, $(libs-y)))
991 virt-y := $(patsubst %/, %/built-in.a, $(virt-y))
993 # Externally visible symbols (used by link-vmlinux.sh)
994 export KBUILD_VMLINUX_OBJS := $(head-y) $(init-y) $(core-y) $(libs-y2) \
995 $(drivers-y) $(net-y) $(virt-y)
996 export KBUILD_VMLINUX_LIBS := $(libs-y1)
997 export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
998 export LDFLAGS_vmlinux
999 # used by scripts/package/Makefile
1000 export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) arch Documentation include samples scripts tools)
1002 vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
1004 # Recurse until adjust_autoksyms.sh is satisfied
1005 PHONY += autoksyms_recursive
1006 autoksyms_recursive: $(vmlinux-deps)
1007 ifdef CONFIG_TRIM_UNUSED_KSYMS
1008 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1009 "$(MAKE) -f $(srctree)/Makefile vmlinux"
1012 # For the kernel to actually contain only the needed exported symbols,
1013 # we have to build modules as well to determine what those symbols are.
1014 # (this can be evaluated only once include/config/auto.conf has been included)
1015 ifdef CONFIG_TRIM_UNUSED_KSYMS
1019 autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1022 $(Q)mkdir -p $(dir $@)
1025 ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1027 # Final link of vmlinux with optional arch pass after final link
1028 cmd_link-vmlinux = \
1029 $(CONFIG_SHELL) $< $(LD) $(KBUILD_LDFLAGS) $(LDFLAGS_vmlinux) ; \
1030 $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1032 vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1033 +$(call if_changed,link-vmlinux)
1037 # Build samples along the rest of the kernel. This needs headers_install.
1038 ifdef CONFIG_SAMPLES
1039 vmlinux-dirs += samples
1040 samples: headers_install
1043 # The actual objects are generated when descending,
1044 # make sure no implicit rule kicks in
1045 $(sort $(vmlinux-deps)): $(vmlinux-dirs) ;
1047 # Handle descending into subdirectories listed in $(vmlinux-dirs)
1048 # Preset locale variables to speed up the build process. Limit locale
1049 # tweaks to this spot to avoid wrong language settings when running
1050 # make menuconfig etc.
1051 # Error messages still appears in the original language
1053 PHONY += $(vmlinux-dirs)
1054 $(vmlinux-dirs): prepare
1055 $(Q)$(MAKE) $(build)=$@ need-builtin=1
1057 filechk_kernel.release = \
1058 echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1060 # Store (new) KERNELRELEASE string in include/config/kernel.release
1061 include/config/kernel.release: $(srctree)/Makefile FORCE
1062 $(call filechk,kernel.release)
1064 # Additional helpers built in scripts/
1065 # Carefully list dependencies so we do not try to build scripts twice
1068 scripts: scripts_basic scripts_dtc
1069 $(Q)$(MAKE) $(build)=$(@)
1071 # Things we need to do before we recursively start building the kernel
1072 # or the modules are listed in "prepare".
1073 # A multi level approach is used. prepareN is processed before prepareN-1.
1074 # archprepare is used in arch Makefiles and when processed asm symlink,
1075 # version.h and scripts_basic is processed / created.
1077 PHONY += prepare archprepare prepare1 prepare3
1079 # prepare3 is used to check if we are building in a separate output directory,
1081 # 1) Check that make has not been executed in the kernel src $(srctree)
1082 prepare3: include/config/kernel.release
1083 ifneq ($(KBUILD_SRC),)
1084 @$(kecho) ' Using $(srctree) as source for kernel'
1085 $(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \
1086 echo >&2 " $(srctree) is not clean, please run 'make mrproper'"; \
1087 echo >&2 " in the '$(srctree)' directory.";\
1092 prepare1: prepare3 outputmakefile asm-generic $(version_h) $(autoksyms_h) \
1093 include/generated/utsrelease.h
1096 archprepare: archheaders archscripts prepare1 scripts
1098 prepare0: archprepare
1099 $(Q)$(MAKE) $(build)=scripts/mod
1100 $(Q)$(MAKE) $(build)=.
1102 # All the preparing..
1103 prepare: prepare0 prepare-objtool
1105 # Support for using generic headers in asm-generic
1106 asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1108 PHONY += asm-generic uapi-asm-generic
1109 asm-generic: uapi-asm-generic
1110 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1111 generic=include/asm-generic
1113 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1114 generic=include/uapi/asm-generic
1116 PHONY += prepare-objtool
1117 prepare-objtool: $(objtool_target)
1118 ifeq ($(SKIP_STACK_VALIDATION),1)
1119 ifdef CONFIG_UNWINDER_ORC
1120 @echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1123 @echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1127 # Generate some files
1128 # ---------------------------------------------------------------------------
1130 # KERNELRELEASE can change from a few different places, meaning version.h
1131 # needs to be updated, so this check is forced on all builds
1134 define filechk_utsrelease.h
1135 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1136 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1139 echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1142 define filechk_version.h
1143 echo \#define LINUX_VERSION_CODE $(shell \
1144 expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1145 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))'
1149 $(call filechk,version.h)
1150 $(Q)rm -f $(old_version_h)
1152 include/generated/utsrelease.h: include/config/kernel.release FORCE
1153 $(call filechk,utsrelease.h)
1157 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1158 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1160 # ---------------------------------------------------------------------------
1163 #Default location for installed headers
1164 export INSTALL_HDR_PATH = $(objtree)/usr
1166 # If we do an all arch process set dst to include/arch-$(SRCARCH)
1167 hdr-dst = $(if $(KBUILD_HEADERS), dst=include/arch-$(SRCARCH), dst=include)
1169 PHONY += archheaders archscripts
1172 __headers: $(version_h) scripts_basic uapi-asm-generic archheaders archscripts
1173 $(Q)$(MAKE) $(build)=scripts build_unifdef
1175 PHONY += headers_install_all
1176 headers_install_all:
1177 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh install
1179 PHONY += headers_install
1180 headers_install: __headers
1181 $(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1182 $(error Headers not exportable for the $(SRCARCH) architecture))
1183 $(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include
1184 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi $(hdr-dst)
1186 PHONY += headers_check_all
1187 headers_check_all: headers_install_all
1188 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh check
1190 PHONY += headers_check
1191 headers_check: headers_install
1192 $(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include HDRCHECK=1
1193 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi $(hdr-dst) HDRCHECK=1
1195 ifdef CONFIG_HEADERS_CHECK
1199 # ---------------------------------------------------------------------------
1204 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1206 PHONY += kselftest-clean
1208 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests clean
1210 PHONY += kselftest-merge
1212 $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1213 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/kconfig/merge_config.sh \
1214 -m $(objtree)/.config \
1215 $(srctree)/tools/testing/selftests/*/config
1216 +$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1218 # ---------------------------------------------------------------------------
1221 ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1222 dtstree := arch/$(SRCARCH)/boot/dts
1227 %.dtb: prepare3 scripts_dtc
1228 $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1230 PHONY += dtbs dtbs_install dt_binding_check
1231 dtbs dtbs_check: prepare3 scripts_dtc
1232 $(Q)$(MAKE) $(build)=$(dtstree)
1234 dtbs_check: export CHECK_DTBS=1
1235 dtbs_check: dt_binding_check
1238 $(Q)$(MAKE) $(dtbinst)=$(dtstree)
1240 ifdef CONFIG_OF_EARLY_FLATTREE
1246 PHONY += scripts_dtc
1247 scripts_dtc: scripts_basic
1248 $(Q)$(MAKE) $(build)=scripts/dtc
1250 dt_binding_check: scripts_dtc
1251 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1253 # ---------------------------------------------------------------------------
1256 ifdef CONFIG_MODULES
1258 # By default, build modules as well
1264 # A module can be listed more than once in obj-m resulting in
1265 # duplicate lines in modules.order files. Those are removed
1266 # using awk while concatenating to the final file.
1269 modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux) modules.builtin
1270 $(Q)$(AWK) '!x[$$0]++' $(vmlinux-dirs:%=$(objtree)/%/modules.order) > $(objtree)/modules.order
1271 @$(kecho) ' Building modules, stage 2.';
1272 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1274 modules.builtin: $(vmlinux-dirs:%=%/modules.builtin)
1275 $(Q)$(AWK) '!x[$$0]++' $^ > $(objtree)/modules.builtin
1277 %/modules.builtin: include/config/auto.conf include/config/tristate.conf
1278 $(Q)$(MAKE) $(modbuiltin)=$*
1281 # Target to prepare building external modules
1282 PHONY += modules_prepare
1283 modules_prepare: prepare
1285 # Target to install modules
1286 PHONY += modules_install
1287 modules_install: _modinst_ _modinst_post
1291 @rm -rf $(MODLIB)/kernel
1292 @rm -f $(MODLIB)/source
1293 @mkdir -p $(MODLIB)/kernel
1294 @ln -s $(abspath $(srctree)) $(MODLIB)/source
1295 @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
1296 rm -f $(MODLIB)/build ; \
1297 ln -s $(CURDIR) $(MODLIB)/build ; \
1299 @cp -f $(objtree)/modules.order $(MODLIB)/
1300 @cp -f $(objtree)/modules.builtin $(MODLIB)/
1301 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1303 # This depmod is only for convenience to give the initial
1304 # boot a modules.dep even before / is mounted read-write. However the
1305 # boot script depmod is the master version.
1306 PHONY += _modinst_post
1307 _modinst_post: _modinst_
1310 ifeq ($(CONFIG_MODULE_SIG), y)
1311 PHONY += modules_sign
1313 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1316 else # CONFIG_MODULES
1318 # Modules not configured
1319 # ---------------------------------------------------------------------------
1321 PHONY += modules modules_install
1322 modules modules_install:
1324 @echo >&2 "The present kernel configuration has modules disabled."
1325 @echo >&2 "Type 'make config' and enable loadable module support."
1326 @echo >&2 "Then build a kernel with module support enabled."
1330 endif # CONFIG_MODULES
1333 # Cleaning is done on three levels.
1334 # make clean Delete most generated files
1335 # Leave enough to build external modules
1336 # make mrproper Delete the current configuration, and all generated files
1337 # make distclean Remove editor backup files, patch leftover files and the like
1339 # Directories & files removed with 'make clean'
1340 CLEAN_DIRS += $(MODVERDIR) include/ksym
1342 # Directories & files removed with 'make mrproper'
1343 MRPROPER_DIRS += include/config usr/include include/generated \
1344 arch/*/include/generated .tmp_objdiff
1345 MRPROPER_FILES += .config .config.old .version \
1346 Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS \
1347 signing_key.pem signing_key.priv signing_key.x509 \
1348 x509.genkey extra_certificates signing_key.x509.keyid \
1349 signing_key.x509.signer vmlinux-gdb.py
1351 # clean - Delete most, but leave enough to build external modules
1353 clean: rm-dirs := $(CLEAN_DIRS)
1354 clean: rm-files := $(CLEAN_FILES)
1355 clean-dirs := $(addprefix _clean_, . $(vmlinux-alldirs) Documentation samples)
1357 PHONY += $(clean-dirs) clean archclean vmlinuxclean
1359 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1362 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1363 $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1365 clean: archclean vmlinuxclean
1367 # mrproper - Delete all generated files, including .config
1369 mrproper: rm-dirs := $(wildcard $(MRPROPER_DIRS))
1370 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1371 mrproper-dirs := $(addprefix _mrproper_,scripts)
1373 PHONY += $(mrproper-dirs) mrproper
1375 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1377 mrproper: clean $(mrproper-dirs)
1386 @find $(srctree) $(RCS_FIND_IGNORE) \
1387 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1388 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1389 -o -name 'core' \) \
1390 -type f -print | xargs rm -f
1393 # Packaging of the kernel to various formats
1394 # ---------------------------------------------------------------------------
1395 package-dir := scripts/package
1398 $(Q)$(MAKE) $(build)=$(package-dir) $@
1399 %pkg: include/config/kernel.release FORCE
1400 $(Q)$(MAKE) $(build)=$(package-dir) $@
1403 # Brief documentation of the typical targets used
1404 # ---------------------------------------------------------------------------
1406 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1407 boards := $(sort $(notdir $(boards)))
1408 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1409 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1413 @echo 'Cleaning targets:'
1414 @echo ' clean - Remove most generated files but keep the config and'
1415 @echo ' enough build support to build external modules'
1416 @echo ' mrproper - Remove all generated files + config + various backup files'
1417 @echo ' distclean - mrproper + remove editor backup and patch files'
1419 @echo 'Configuration targets:'
1420 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1422 @echo 'Other generic targets:'
1423 @echo ' all - Build all targets marked with [*]'
1424 @echo '* vmlinux - Build the bare kernel'
1425 @echo '* modules - Build all modules'
1426 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1427 @echo ' dir/ - Build all files in dir and below'
1428 @echo ' dir/file.[ois] - Build specified target only'
1429 @echo ' dir/file.ll - Build the LLVM assembly file'
1430 @echo ' (requires compiler support for LLVM assembly generation)'
1431 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1432 @echo ' (requires a recent binutils and recent build (System.map))'
1433 @echo ' dir/file.ko - Build module including final link'
1434 @echo ' modules_prepare - Set up for building external modules'
1435 @echo ' tags/TAGS - Generate tags file for editors'
1436 @echo ' cscope - Generate cscope index'
1437 @echo ' gtags - Generate GNU GLOBAL index'
1438 @echo ' kernelrelease - Output the release version string (use with make -s)'
1439 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1440 @echo ' image_name - Output the image name (use with make -s)'
1441 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1442 echo ' (default: $(INSTALL_HDR_PATH))'; \
1444 @echo 'Static analysers:'
1445 @echo ' checkstack - Generate a list of stack hogs'
1446 @echo ' namespacecheck - Name space analysis on compiled kernel'
1447 @echo ' versioncheck - Sanity check on version.h usage'
1448 @echo ' includecheck - Check for duplicate included header files'
1449 @echo ' export_report - List the usages of all exported symbols'
1450 @echo ' headers_check - Sanity check on exported headers'
1451 @echo ' headerdep - Detect inclusion cycles in headers'
1452 @echo ' coccicheck - Check with Coccinelle'
1454 @echo 'Kernel selftest:'
1455 @echo ' kselftest - Build and run kernel selftest (run as root)'
1456 @echo ' Build, install, and boot kernel before'
1457 @echo ' running kselftest on it'
1458 @echo ' kselftest-clean - Remove all generated kselftest files'
1459 @echo ' kselftest-merge - Merge all the config dependencies of kselftest to existing'
1463 echo 'Devicetree:'; \
1464 echo '* dtbs - Build device tree blobs for enabled boards'; \
1465 echo ' dtbs_install - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1468 @echo 'Userspace tools targets:'
1469 @echo ' use "make tools/help"'
1470 @echo ' or "cd tools; make help"'
1472 @echo 'Kernel packaging:'
1473 @$(MAKE) $(build)=$(package-dir) help
1475 @echo 'Documentation targets:'
1476 @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1478 @echo 'Architecture specific targets ($(SRCARCH)):'
1479 @$(if $(archhelp),$(archhelp),\
1480 echo ' No architecture specific help defined for $(SRCARCH)')
1483 $(foreach b, $(boards), \
1484 printf " %-24s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1486 @$(if $(board-dirs), \
1487 $(foreach b, $(board-dirs), \
1488 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1489 printf " %-16s - Show all of the above\\n" help-boards; \
1492 @echo ' make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1493 @echo ' make V=2 [targets] 2 => give reason for rebuild of target'
1494 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1495 @echo ' make C=1 [targets] Check re-compiled c source with $$CHECK (sparse by default)'
1496 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1497 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1498 @echo ' make W=n [targets] Enable extra gcc checks, n=1,2,3 where'
1499 @echo ' 1: warnings which may be relevant and do not occur too often'
1500 @echo ' 2: warnings which occur quite often but may still be relevant'
1501 @echo ' 3: more obscure warnings, can most likely be ignored'
1502 @echo ' Multiple levels can be combined with W=12 or W=123'
1504 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1505 @echo 'For further info see the ./README file'
1508 help-board-dirs := $(addprefix help-,$(board-dirs))
1510 help-boards: $(help-board-dirs)
1512 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1514 $(help-board-dirs): help-%:
1515 @echo 'Architecture specific targets ($(SRCARCH) $*):'
1516 @$(if $(boards-per-dir), \
1517 $(foreach b, $(boards-per-dir), \
1518 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1522 # Documentation targets
1523 # ---------------------------------------------------------------------------
1524 DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1525 linkcheckdocs dochelp refcheckdocs
1526 PHONY += $(DOC_TARGETS)
1527 $(DOC_TARGETS): scripts_basic FORCE
1528 $(Q)$(MAKE) $(build)=Documentation $@
1531 # ---------------------------------------------------------------------------
1533 PHONY += scripts_gdb
1534 scripts_gdb: prepare
1535 $(Q)$(MAKE) $(build)=scripts/gdb
1536 $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1538 ifdef CONFIG_GDB_SCRIPTS
1542 else # KBUILD_EXTMOD
1545 # External module support.
1546 # When building external modules the kernel used as basis is considered
1547 # read-only, and no consistency checks are made and the make
1548 # system is not used on the basis kernel. If updates are required
1549 # in the basis kernel ordinary make commands (without M=...) must
1552 # The following are the only valid targets when building external
1554 # make M=dir clean Delete all automatically generated files
1555 # make M=dir modules Make all modules in specified dir
1556 # make M=dir Same as 'make M=dir modules'
1557 # make M=dir modules_install
1558 # Install the modules built in the module directory
1559 # Assumes install directory is already created
1561 # We are always building modules
1564 PHONY += $(objtree)/Module.symvers
1565 $(objtree)/Module.symvers:
1566 @test -e $(objtree)/Module.symvers || ( \
1568 echo " WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1569 echo " is missing; modules will have no dependencies and modversions."; \
1572 module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
1573 PHONY += $(module-dirs) modules
1574 $(module-dirs): prepare $(objtree)/Module.symvers
1575 $(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@)
1577 modules: $(module-dirs)
1578 @$(kecho) ' Building modules, stage 2.';
1579 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1581 PHONY += modules_install
1582 modules_install: _emodinst_ _emodinst_post
1584 install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1587 $(Q)mkdir -p $(MODLIB)/$(install-dir)
1588 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1590 PHONY += _emodinst_post
1591 _emodinst_post: _emodinst_
1594 clean-dirs := $(addprefix _clean_,$(KBUILD_EXTMOD))
1596 PHONY += $(clean-dirs) clean
1598 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1600 clean: rm-dirs := $(MODVERDIR)
1601 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers
1605 @echo ' Building external modules.'
1606 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1608 @echo ' modules - default target, build the module(s)'
1609 @echo ' modules_install - install the module'
1610 @echo ' clean - remove generated files in module directory only'
1616 endif # KBUILD_EXTMOD
1618 clean: $(clean-dirs)
1621 @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1622 \( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1624 -o -name '*.dtb' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1625 -o -name '*.dwo' -o -name '*.lst' \
1627 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1628 -o -name '*.lex.c' -o -name '*.tab.[ch]' \
1629 -o -name '*.asn1.[ch]' \
1630 -o -name '*.symtypes' -o -name 'modules.order' \
1631 -o -name modules.builtin -o -name '.tmp_*.o.*' \
1632 -o -name '*.c.[012]*.*' \
1634 -o -name '*.gcno' \) -type f -print | xargs rm -f
1636 # Generate tags for editors
1637 # ---------------------------------------------------------------------------
1638 quiet_cmd_tags = GEN $@
1639 cmd_tags = $(CONFIG_SHELL) $(srctree)/scripts/tags.sh $@
1641 tags TAGS cscope gtags: FORCE
1644 # Scripts to check various things for consistency
1645 # ---------------------------------------------------------------------------
1647 PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1650 find $(srctree)/* $(RCS_FIND_IGNORE) \
1651 -name '*.[hcS]' -type f -print | sort \
1652 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1655 find $(srctree)/* $(RCS_FIND_IGNORE) \
1656 -name '*.[hcS]' -type f -print | sort \
1657 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1660 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/$@
1663 $(PERL) $(srctree)/scripts/namespace.pl
1666 $(PERL) $(srctree)/scripts/export_report.pl
1668 PHONY += checkstack kernelrelease kernelversion image_name
1670 # UML needs a little special treatment here. It wants to use the host
1671 # toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
1672 # else wants $(ARCH), including people doing cross-builds, which means
1673 # that $(SUBARCH) doesn't work here.
1675 CHECKSTACK_ARCH := $(SUBARCH)
1677 CHECKSTACK_ARCH := $(ARCH)
1680 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1681 $(PERL) $(src)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1684 @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1687 @echo $(KERNELVERSION)
1690 @echo $(KBUILD_IMAGE)
1692 # Clear a bunch of variables before executing the submake
1694 ifeq ($(quiet),silent_)
1699 $(Q)mkdir -p $(objtree)/tools
1700 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(src)/tools/
1703 $(Q)mkdir -p $(objtree)/tools
1704 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(src)/tools/ $*
1707 # ---------------------------------------------------------------------------
1708 # Single targets are compatible with:
1709 # - build with mixed source and output
1710 # - build with separate output dir 'make O=...'
1711 # - external modules
1713 # target-dir => where to store outputfile
1714 # build-dir => directory in kernel source tree to use
1716 build-target = $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD)/)$@
1717 build-dir = $(patsubst %/,%,$(dir $(build-target)))
1720 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1722 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1723 %.lst: prepare FORCE
1724 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1726 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1728 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1729 %.symtypes: prepare FORCE
1730 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1732 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1738 # Make sure the latest headers are built for Documentation
1739 Documentation/ samples/: headers_install
1741 $(Q)$(MAKE) KBUILD_MODULES=1 $(build)=$(build-dir)
1743 # FIXME Should go into a make.lib or something
1744 # ===========================================================================
1746 quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN $(wildcard $(rm-dirs)))
1747 cmd_rmdirs = rm -rf $(rm-dirs)
1749 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
1750 cmd_rmfiles = rm -f $(rm-files)
1752 # Run depmod only if we have System.map and depmod is executable
1753 quiet_cmd_depmod = DEPMOD $(KERNELRELEASE)
1754 cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1757 # Create temporary dir for module support files
1758 # clean it up only when building all modules
1759 cmd_crmodverdir = $(Q)mkdir -p $(MODVERDIR) \
1760 $(if $(KBUILD_MODULES),; rm -f $(MODVERDIR)/*)
1762 # read saved command lines for existing targets
1763 existing-targets := $(wildcard $(sort $(targets)))
1765 -include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
1767 endif # ifeq ($(config-targets),1)
1768 endif # ifeq ($(mixed-targets),1)
1769 endif # need-sub-make
1774 # Declare the contents of the PHONY variable as phony. We keep that
1775 # information in a variable so we can use it in if_changed and friends.