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 # Initialize all stack variables with a pattern, if desired.
752 ifdef CONFIG_INIT_STACK_ALL
753 KBUILD_CFLAGS += -ftrivial-auto-var-init=pattern
756 DEBUG_CFLAGS := $(call cc-option, -fno-var-tracking-assignments)
758 ifdef CONFIG_DEBUG_INFO
759 ifdef CONFIG_DEBUG_INFO_SPLIT
760 DEBUG_CFLAGS += -gsplit-dwarf
764 KBUILD_AFLAGS += -Wa,-gdwarf-2
766 ifdef CONFIG_DEBUG_INFO_DWARF4
767 DEBUG_CFLAGS += -gdwarf-4
770 ifdef CONFIG_DEBUG_INFO_REDUCED
771 DEBUG_CFLAGS += $(call cc-option, -femit-struct-debug-baseonly) \
772 $(call cc-option,-fno-var-tracking)
775 KBUILD_CFLAGS += $(DEBUG_CFLAGS)
778 ifdef CONFIG_FUNCTION_TRACER
779 ifdef CONFIG_FTRACE_MCOUNT_RECORD
780 # gcc 5 supports generating the mcount tables directly
781 ifeq ($(call cc-option-yn,-mrecord-mcount),y)
782 CC_FLAGS_FTRACE += -mrecord-mcount
783 export CC_USING_RECORD_MCOUNT := 1
785 ifdef CONFIG_HAVE_NOP_MCOUNT
786 ifeq ($(call cc-option-yn, -mnop-mcount),y)
787 CC_FLAGS_FTRACE += -mnop-mcount
788 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
792 ifdef CONFIG_HAVE_FENTRY
793 ifeq ($(call cc-option-yn, -mfentry),y)
794 CC_FLAGS_FTRACE += -mfentry
795 CC_FLAGS_USING += -DCC_USING_FENTRY
798 export CC_FLAGS_FTRACE
799 KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
800 KBUILD_AFLAGS += $(CC_FLAGS_USING)
801 ifdef CONFIG_DYNAMIC_FTRACE
802 ifdef CONFIG_HAVE_C_RECORDMCOUNT
803 BUILD_C_RECORDMCOUNT := y
804 export BUILD_C_RECORDMCOUNT
809 # We trigger additional mismatches with less inlining
810 ifdef CONFIG_DEBUG_SECTION_MISMATCH
811 KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
814 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
815 KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
816 LDFLAGS_vmlinux += --gc-sections
819 ifdef CONFIG_LIVEPATCH
820 KBUILD_CFLAGS += $(call cc-option, -flive-patching=inline-clone)
823 # arch Makefile may override CC so keep this after arch Makefile is included
824 NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
826 # warn about C99 declaration after statement
827 KBUILD_CFLAGS += -Wdeclaration-after-statement
829 # Variable Length Arrays (VLAs) should not be used anywhere in the kernel
830 KBUILD_CFLAGS += $(call cc-option,-Wvla)
832 # disable pointer signed / unsigned warnings in gcc 4.0
833 KBUILD_CFLAGS += -Wno-pointer-sign
835 # disable stringop warnings in gcc 8+
836 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
838 # disable invalid "can't wrap" optimizations for signed / pointers
839 KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow)
841 # clang sets -fmerge-all-constants by default as optimization, but this
842 # is non-conforming behavior for C and in fact breaks the kernel, so we
843 # need to disable it here generally.
844 KBUILD_CFLAGS += $(call cc-option,-fno-merge-all-constants)
846 # for gcc -fno-merge-all-constants disables everything, but it is fine
847 # to have actual conforming behavior enabled.
848 KBUILD_CFLAGS += $(call cc-option,-fmerge-constants)
850 # Make sure -fstack-check isn't enabled (like gentoo apparently did)
851 KBUILD_CFLAGS += $(call cc-option,-fno-stack-check,)
853 # conserve stack if available
854 KBUILD_CFLAGS += $(call cc-option,-fconserve-stack)
856 # Prohibit date/time macros, which would make the build non-deterministic
857 KBUILD_CFLAGS += $(call cc-option,-Werror=date-time)
859 # enforce correct pointer usage
860 KBUILD_CFLAGS += $(call cc-option,-Werror=incompatible-pointer-types)
862 # Require designated initializers for all marked structures
863 KBUILD_CFLAGS += $(call cc-option,-Werror=designated-init)
865 # change __FILE__ to the relative path from the srctree
866 KBUILD_CFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
868 # use the deterministic mode of AR if available
869 KBUILD_ARFLAGS := $(call ar-option,D)
871 include scripts/Makefile.kasan
872 include scripts/Makefile.extrawarn
873 include scripts/Makefile.ubsan
875 # Add any arch overrides and user supplied CPPFLAGS, AFLAGS and CFLAGS as the
877 KBUILD_CPPFLAGS += $(ARCH_CPPFLAGS) $(KCPPFLAGS)
878 KBUILD_AFLAGS += $(ARCH_AFLAGS) $(KAFLAGS)
879 KBUILD_CFLAGS += $(ARCH_CFLAGS) $(KCFLAGS)
881 # Use --build-id when available.
882 LDFLAGS_BUILD_ID := $(call ld-option, --build-id)
883 KBUILD_LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID)
884 LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)
886 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
887 LDFLAGS_vmlinux += $(call ld-option, -X,)
890 # insure the checker run with the right endianness
891 CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
893 # the checker needs the correct machine size
894 CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
896 # Default kernel image to build when no specific target is given.
897 # KBUILD_IMAGE may be overruled on the command line or
898 # set in the environment
899 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
901 export KBUILD_IMAGE ?= vmlinux
904 # INSTALL_PATH specifies where to place the updated kernel and system map
905 # images. Default is /boot, but you can set it to other values
906 export INSTALL_PATH ?= /boot
909 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
910 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
911 # an argument if needed. Otherwise it defaults to the kernel install path
913 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
916 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
917 # relocations required by build roots. This is not defined in the
918 # makefile but the argument can be passed to make if needed.
921 MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
925 # INSTALL_MOD_STRIP, if defined, will cause modules to be
926 # stripped after they are installed. If INSTALL_MOD_STRIP is '1', then
927 # the default option --strip-debug will be used. Otherwise,
928 # INSTALL_MOD_STRIP value will be used as the options to the strip command.
930 ifdef INSTALL_MOD_STRIP
931 ifeq ($(INSTALL_MOD_STRIP),1)
932 mod_strip_cmd = $(STRIP) --strip-debug
934 mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
935 endif # INSTALL_MOD_STRIP=1
938 endif # INSTALL_MOD_STRIP
941 # CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
942 # after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
943 # or CONFIG_MODULE_COMPRESS_XZ.
945 mod_compress_cmd = true
946 ifdef CONFIG_MODULE_COMPRESS
947 ifdef CONFIG_MODULE_COMPRESS_GZIP
948 mod_compress_cmd = gzip -n -f
949 endif # CONFIG_MODULE_COMPRESS_GZIP
950 ifdef CONFIG_MODULE_COMPRESS_XZ
951 mod_compress_cmd = xz -f
952 endif # CONFIG_MODULE_COMPRESS_XZ
953 endif # CONFIG_MODULE_COMPRESS
954 export mod_compress_cmd
956 ifdef CONFIG_MODULE_SIG_ALL
957 $(eval $(call config_filename,MODULE_SIG_KEY))
959 mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
965 HOST_LIBELF_LIBS = $(shell pkg-config libelf --libs 2>/dev/null || echo -lelf)
967 ifdef CONFIG_STACK_VALIDATION
968 has_libelf := $(call try-run,\
969 echo "int main() {}" | $(HOSTCC) -xc -o /dev/null $(HOST_LIBELF_LIBS) -,1,0)
970 ifeq ($(has_libelf),1)
971 objtool_target := tools/objtool FORCE
973 SKIP_STACK_VALIDATION := 1
974 export SKIP_STACK_VALIDATION
980 ifeq ($(KBUILD_EXTMOD),)
981 core-y += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
983 vmlinux-dirs := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
984 $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
985 $(net-y) $(net-m) $(libs-y) $(libs-m) $(virt-y)))
987 vmlinux-alldirs := $(sort $(vmlinux-dirs) $(patsubst %/,%,$(filter %/, \
988 $(init-) $(core-) $(drivers-) $(net-) $(libs-) $(virt-))))
990 init-y := $(patsubst %/, %/built-in.a, $(init-y))
991 core-y := $(patsubst %/, %/built-in.a, $(core-y))
992 drivers-y := $(patsubst %/, %/built-in.a, $(drivers-y))
993 net-y := $(patsubst %/, %/built-in.a, $(net-y))
994 libs-y1 := $(patsubst %/, %/lib.a, $(libs-y))
995 libs-y2 := $(patsubst %/, %/built-in.a, $(filter-out %.a, $(libs-y)))
996 virt-y := $(patsubst %/, %/built-in.a, $(virt-y))
998 # Externally visible symbols (used by link-vmlinux.sh)
999 export KBUILD_VMLINUX_OBJS := $(head-y) $(init-y) $(core-y) $(libs-y2) \
1000 $(drivers-y) $(net-y) $(virt-y)
1001 export KBUILD_VMLINUX_LIBS := $(libs-y1)
1002 export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
1003 export LDFLAGS_vmlinux
1004 # used by scripts/package/Makefile
1005 export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) arch Documentation include samples scripts tools)
1007 vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
1009 # Recurse until adjust_autoksyms.sh is satisfied
1010 PHONY += autoksyms_recursive
1011 autoksyms_recursive: $(vmlinux-deps)
1012 ifdef CONFIG_TRIM_UNUSED_KSYMS
1013 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1014 "$(MAKE) -f $(srctree)/Makefile vmlinux"
1017 # For the kernel to actually contain only the needed exported symbols,
1018 # we have to build modules as well to determine what those symbols are.
1019 # (this can be evaluated only once include/config/auto.conf has been included)
1020 ifdef CONFIG_TRIM_UNUSED_KSYMS
1024 autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1027 $(Q)mkdir -p $(dir $@)
1030 ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1032 # Final link of vmlinux with optional arch pass after final link
1033 cmd_link-vmlinux = \
1034 $(CONFIG_SHELL) $< $(LD) $(KBUILD_LDFLAGS) $(LDFLAGS_vmlinux) ; \
1035 $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1037 vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1038 +$(call if_changed,link-vmlinux)
1042 # Build samples along the rest of the kernel. This needs headers_install.
1043 ifdef CONFIG_SAMPLES
1044 vmlinux-dirs += samples
1045 samples: headers_install
1048 # The actual objects are generated when descending,
1049 # make sure no implicit rule kicks in
1050 $(sort $(vmlinux-deps)): $(vmlinux-dirs) ;
1052 # Handle descending into subdirectories listed in $(vmlinux-dirs)
1053 # Preset locale variables to speed up the build process. Limit locale
1054 # tweaks to this spot to avoid wrong language settings when running
1055 # make menuconfig etc.
1056 # Error messages still appears in the original language
1058 PHONY += $(vmlinux-dirs)
1059 $(vmlinux-dirs): prepare
1060 $(Q)$(MAKE) $(build)=$@ need-builtin=1
1062 filechk_kernel.release = \
1063 echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1065 # Store (new) KERNELRELEASE string in include/config/kernel.release
1066 include/config/kernel.release: $(srctree)/Makefile FORCE
1067 $(call filechk,kernel.release)
1069 # Additional helpers built in scripts/
1070 # Carefully list dependencies so we do not try to build scripts twice
1073 scripts: scripts_basic scripts_dtc
1074 $(Q)$(MAKE) $(build)=$(@)
1076 # Things we need to do before we recursively start building the kernel
1077 # or the modules are listed in "prepare".
1078 # A multi level approach is used. prepareN is processed before prepareN-1.
1079 # archprepare is used in arch Makefiles and when processed asm symlink,
1080 # version.h and scripts_basic is processed / created.
1082 PHONY += prepare archprepare prepare1 prepare3
1084 # prepare3 is used to check if we are building in a separate output directory,
1086 # 1) Check that make has not been executed in the kernel src $(srctree)
1087 prepare3: include/config/kernel.release
1088 ifneq ($(KBUILD_SRC),)
1089 @$(kecho) ' Using $(srctree) as source for kernel'
1090 $(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \
1091 echo >&2 " $(srctree) is not clean, please run 'make mrproper'"; \
1092 echo >&2 " in the '$(srctree)' directory.";\
1097 prepare1: prepare3 outputmakefile asm-generic $(version_h) $(autoksyms_h) \
1098 include/generated/utsrelease.h
1101 archprepare: archheaders archscripts prepare1 scripts
1103 prepare0: archprepare
1104 $(Q)$(MAKE) $(build)=scripts/mod
1105 $(Q)$(MAKE) $(build)=.
1107 # All the preparing..
1108 prepare: prepare0 prepare-objtool
1110 # Support for using generic headers in asm-generic
1111 asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1113 PHONY += asm-generic uapi-asm-generic
1114 asm-generic: uapi-asm-generic
1115 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1116 generic=include/asm-generic
1118 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1119 generic=include/uapi/asm-generic
1121 PHONY += prepare-objtool
1122 prepare-objtool: $(objtool_target)
1123 ifeq ($(SKIP_STACK_VALIDATION),1)
1124 ifdef CONFIG_UNWINDER_ORC
1125 @echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1128 @echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1132 # Generate some files
1133 # ---------------------------------------------------------------------------
1135 # KERNELRELEASE can change from a few different places, meaning version.h
1136 # needs to be updated, so this check is forced on all builds
1139 define filechk_utsrelease.h
1140 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1141 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1144 echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1147 define filechk_version.h
1148 echo \#define LINUX_VERSION_CODE $(shell \
1149 expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1150 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))'
1154 $(call filechk,version.h)
1155 $(Q)rm -f $(old_version_h)
1157 include/generated/utsrelease.h: include/config/kernel.release FORCE
1158 $(call filechk,utsrelease.h)
1162 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1163 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1165 # ---------------------------------------------------------------------------
1168 #Default location for installed headers
1169 export INSTALL_HDR_PATH = $(objtree)/usr
1171 # If we do an all arch process set dst to include/arch-$(SRCARCH)
1172 hdr-dst = $(if $(KBUILD_HEADERS), dst=include/arch-$(SRCARCH), dst=include)
1174 PHONY += archheaders archscripts
1177 __headers: $(version_h) scripts_basic uapi-asm-generic archheaders archscripts
1178 $(Q)$(MAKE) $(build)=scripts build_unifdef
1180 PHONY += headers_install_all
1181 headers_install_all:
1182 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh install
1184 PHONY += headers_install
1185 headers_install: __headers
1186 $(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1187 $(error Headers not exportable for the $(SRCARCH) architecture))
1188 $(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include
1189 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi $(hdr-dst)
1191 PHONY += headers_check_all
1192 headers_check_all: headers_install_all
1193 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh check
1195 PHONY += headers_check
1196 headers_check: headers_install
1197 $(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include HDRCHECK=1
1198 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi $(hdr-dst) HDRCHECK=1
1200 ifdef CONFIG_HEADERS_CHECK
1204 # ---------------------------------------------------------------------------
1209 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1211 PHONY += kselftest-clean
1213 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests clean
1215 PHONY += kselftest-merge
1217 $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1218 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/kconfig/merge_config.sh \
1219 -m $(objtree)/.config \
1220 $(srctree)/tools/testing/selftests/*/config
1221 +$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1223 # ---------------------------------------------------------------------------
1226 ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1227 dtstree := arch/$(SRCARCH)/boot/dts
1232 %.dtb: prepare3 scripts_dtc
1233 $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1235 PHONY += dtbs dtbs_install dt_binding_check
1236 dtbs dtbs_check: prepare3 scripts_dtc
1237 $(Q)$(MAKE) $(build)=$(dtstree)
1239 dtbs_check: export CHECK_DTBS=1
1240 dtbs_check: dt_binding_check
1243 $(Q)$(MAKE) $(dtbinst)=$(dtstree)
1245 ifdef CONFIG_OF_EARLY_FLATTREE
1251 PHONY += scripts_dtc
1252 scripts_dtc: scripts_basic
1253 $(Q)$(MAKE) $(build)=scripts/dtc
1255 dt_binding_check: scripts_dtc
1256 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1258 # ---------------------------------------------------------------------------
1261 ifdef CONFIG_MODULES
1263 # By default, build modules as well
1269 # A module can be listed more than once in obj-m resulting in
1270 # duplicate lines in modules.order files. Those are removed
1271 # using awk while concatenating to the final file.
1274 modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux) modules.builtin
1275 $(Q)$(AWK) '!x[$$0]++' $(vmlinux-dirs:%=$(objtree)/%/modules.order) > $(objtree)/modules.order
1276 @$(kecho) ' Building modules, stage 2.';
1277 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1279 modules.builtin: $(vmlinux-dirs:%=%/modules.builtin)
1280 $(Q)$(AWK) '!x[$$0]++' $^ > $(objtree)/modules.builtin
1282 %/modules.builtin: include/config/auto.conf include/config/tristate.conf
1283 $(Q)$(MAKE) $(modbuiltin)=$*
1286 # Target to prepare building external modules
1287 PHONY += modules_prepare
1288 modules_prepare: prepare
1290 # Target to install modules
1291 PHONY += modules_install
1292 modules_install: _modinst_ _modinst_post
1296 @rm -rf $(MODLIB)/kernel
1297 @rm -f $(MODLIB)/source
1298 @mkdir -p $(MODLIB)/kernel
1299 @ln -s $(abspath $(srctree)) $(MODLIB)/source
1300 @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
1301 rm -f $(MODLIB)/build ; \
1302 ln -s $(CURDIR) $(MODLIB)/build ; \
1304 @cp -f $(objtree)/modules.order $(MODLIB)/
1305 @cp -f $(objtree)/modules.builtin $(MODLIB)/
1306 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1308 # This depmod is only for convenience to give the initial
1309 # boot a modules.dep even before / is mounted read-write. However the
1310 # boot script depmod is the master version.
1311 PHONY += _modinst_post
1312 _modinst_post: _modinst_
1315 ifeq ($(CONFIG_MODULE_SIG), y)
1316 PHONY += modules_sign
1318 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1321 else # CONFIG_MODULES
1323 # Modules not configured
1324 # ---------------------------------------------------------------------------
1326 PHONY += modules modules_install
1327 modules modules_install:
1329 @echo >&2 "The present kernel configuration has modules disabled."
1330 @echo >&2 "Type 'make config' and enable loadable module support."
1331 @echo >&2 "Then build a kernel with module support enabled."
1335 endif # CONFIG_MODULES
1338 # Cleaning is done on three levels.
1339 # make clean Delete most generated files
1340 # Leave enough to build external modules
1341 # make mrproper Delete the current configuration, and all generated files
1342 # make distclean Remove editor backup files, patch leftover files and the like
1344 # Directories & files removed with 'make clean'
1345 CLEAN_DIRS += $(MODVERDIR) include/ksym
1347 # Directories & files removed with 'make mrproper'
1348 MRPROPER_DIRS += include/config usr/include include/generated \
1349 arch/*/include/generated .tmp_objdiff
1350 MRPROPER_FILES += .config .config.old .version \
1351 Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS \
1352 signing_key.pem signing_key.priv signing_key.x509 \
1353 x509.genkey extra_certificates signing_key.x509.keyid \
1354 signing_key.x509.signer vmlinux-gdb.py
1356 # clean - Delete most, but leave enough to build external modules
1358 clean: rm-dirs := $(CLEAN_DIRS)
1359 clean: rm-files := $(CLEAN_FILES)
1360 clean-dirs := $(addprefix _clean_, . $(vmlinux-alldirs) Documentation samples)
1362 PHONY += $(clean-dirs) clean archclean vmlinuxclean
1364 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1367 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1368 $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1370 clean: archclean vmlinuxclean
1372 # mrproper - Delete all generated files, including .config
1374 mrproper: rm-dirs := $(wildcard $(MRPROPER_DIRS))
1375 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1376 mrproper-dirs := $(addprefix _mrproper_,scripts)
1378 PHONY += $(mrproper-dirs) mrproper
1380 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1382 mrproper: clean $(mrproper-dirs)
1391 @find $(srctree) $(RCS_FIND_IGNORE) \
1392 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1393 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1394 -o -name 'core' \) \
1395 -type f -print | xargs rm -f
1398 # Packaging of the kernel to various formats
1399 # ---------------------------------------------------------------------------
1400 package-dir := scripts/package
1403 $(Q)$(MAKE) $(build)=$(package-dir) $@
1404 %pkg: include/config/kernel.release FORCE
1405 $(Q)$(MAKE) $(build)=$(package-dir) $@
1408 # Brief documentation of the typical targets used
1409 # ---------------------------------------------------------------------------
1411 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1412 boards := $(sort $(notdir $(boards)))
1413 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1414 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1418 @echo 'Cleaning targets:'
1419 @echo ' clean - Remove most generated files but keep the config and'
1420 @echo ' enough build support to build external modules'
1421 @echo ' mrproper - Remove all generated files + config + various backup files'
1422 @echo ' distclean - mrproper + remove editor backup and patch files'
1424 @echo 'Configuration targets:'
1425 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1427 @echo 'Other generic targets:'
1428 @echo ' all - Build all targets marked with [*]'
1429 @echo '* vmlinux - Build the bare kernel'
1430 @echo '* modules - Build all modules'
1431 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1432 @echo ' dir/ - Build all files in dir and below'
1433 @echo ' dir/file.[ois] - Build specified target only'
1434 @echo ' dir/file.ll - Build the LLVM assembly file'
1435 @echo ' (requires compiler support for LLVM assembly generation)'
1436 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1437 @echo ' (requires a recent binutils and recent build (System.map))'
1438 @echo ' dir/file.ko - Build module including final link'
1439 @echo ' modules_prepare - Set up for building external modules'
1440 @echo ' tags/TAGS - Generate tags file for editors'
1441 @echo ' cscope - Generate cscope index'
1442 @echo ' gtags - Generate GNU GLOBAL index'
1443 @echo ' kernelrelease - Output the release version string (use with make -s)'
1444 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1445 @echo ' image_name - Output the image name (use with make -s)'
1446 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1447 echo ' (default: $(INSTALL_HDR_PATH))'; \
1449 @echo 'Static analysers:'
1450 @echo ' checkstack - Generate a list of stack hogs'
1451 @echo ' namespacecheck - Name space analysis on compiled kernel'
1452 @echo ' versioncheck - Sanity check on version.h usage'
1453 @echo ' includecheck - Check for duplicate included header files'
1454 @echo ' export_report - List the usages of all exported symbols'
1455 @echo ' headers_check - Sanity check on exported headers'
1456 @echo ' headerdep - Detect inclusion cycles in headers'
1457 @echo ' coccicheck - Check with Coccinelle'
1459 @echo 'Kernel selftest:'
1460 @echo ' kselftest - Build and run kernel selftest (run as root)'
1461 @echo ' Build, install, and boot kernel before'
1462 @echo ' running kselftest on it'
1463 @echo ' kselftest-clean - Remove all generated kselftest files'
1464 @echo ' kselftest-merge - Merge all the config dependencies of kselftest to existing'
1468 echo 'Devicetree:'; \
1469 echo '* dtbs - Build device tree blobs for enabled boards'; \
1470 echo ' dtbs_install - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1473 @echo 'Userspace tools targets:'
1474 @echo ' use "make tools/help"'
1475 @echo ' or "cd tools; make help"'
1477 @echo 'Kernel packaging:'
1478 @$(MAKE) $(build)=$(package-dir) help
1480 @echo 'Documentation targets:'
1481 @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1483 @echo 'Architecture specific targets ($(SRCARCH)):'
1484 @$(if $(archhelp),$(archhelp),\
1485 echo ' No architecture specific help defined for $(SRCARCH)')
1488 $(foreach b, $(boards), \
1489 printf " %-24s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1491 @$(if $(board-dirs), \
1492 $(foreach b, $(board-dirs), \
1493 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1494 printf " %-16s - Show all of the above\\n" help-boards; \
1497 @echo ' make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1498 @echo ' make V=2 [targets] 2 => give reason for rebuild of target'
1499 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1500 @echo ' make C=1 [targets] Check re-compiled c source with $$CHECK (sparse by default)'
1501 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1502 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1503 @echo ' make W=n [targets] Enable extra gcc checks, n=1,2,3 where'
1504 @echo ' 1: warnings which may be relevant and do not occur too often'
1505 @echo ' 2: warnings which occur quite often but may still be relevant'
1506 @echo ' 3: more obscure warnings, can most likely be ignored'
1507 @echo ' Multiple levels can be combined with W=12 or W=123'
1509 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1510 @echo 'For further info see the ./README file'
1513 help-board-dirs := $(addprefix help-,$(board-dirs))
1515 help-boards: $(help-board-dirs)
1517 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1519 $(help-board-dirs): help-%:
1520 @echo 'Architecture specific targets ($(SRCARCH) $*):'
1521 @$(if $(boards-per-dir), \
1522 $(foreach b, $(boards-per-dir), \
1523 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1527 # Documentation targets
1528 # ---------------------------------------------------------------------------
1529 DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1530 linkcheckdocs dochelp refcheckdocs
1531 PHONY += $(DOC_TARGETS)
1532 $(DOC_TARGETS): scripts_basic FORCE
1533 $(Q)$(MAKE) $(build)=Documentation $@
1536 # ---------------------------------------------------------------------------
1538 PHONY += scripts_gdb
1539 scripts_gdb: prepare
1540 $(Q)$(MAKE) $(build)=scripts/gdb
1541 $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1543 ifdef CONFIG_GDB_SCRIPTS
1547 else # KBUILD_EXTMOD
1550 # External module support.
1551 # When building external modules the kernel used as basis is considered
1552 # read-only, and no consistency checks are made and the make
1553 # system is not used on the basis kernel. If updates are required
1554 # in the basis kernel ordinary make commands (without M=...) must
1557 # The following are the only valid targets when building external
1559 # make M=dir clean Delete all automatically generated files
1560 # make M=dir modules Make all modules in specified dir
1561 # make M=dir Same as 'make M=dir modules'
1562 # make M=dir modules_install
1563 # Install the modules built in the module directory
1564 # Assumes install directory is already created
1566 # We are always building modules
1569 PHONY += $(objtree)/Module.symvers
1570 $(objtree)/Module.symvers:
1571 @test -e $(objtree)/Module.symvers || ( \
1573 echo " WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1574 echo " is missing; modules will have no dependencies and modversions."; \
1577 module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
1578 PHONY += $(module-dirs) modules
1579 $(module-dirs): prepare $(objtree)/Module.symvers
1580 $(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@)
1582 modules: $(module-dirs)
1583 @$(kecho) ' Building modules, stage 2.';
1584 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1586 PHONY += modules_install
1587 modules_install: _emodinst_ _emodinst_post
1589 install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1592 $(Q)mkdir -p $(MODLIB)/$(install-dir)
1593 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1595 PHONY += _emodinst_post
1596 _emodinst_post: _emodinst_
1599 clean-dirs := $(addprefix _clean_,$(KBUILD_EXTMOD))
1601 PHONY += $(clean-dirs) clean
1603 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1605 clean: rm-dirs := $(MODVERDIR)
1606 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers
1610 @echo ' Building external modules.'
1611 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1613 @echo ' modules - default target, build the module(s)'
1614 @echo ' modules_install - install the module'
1615 @echo ' clean - remove generated files in module directory only'
1621 endif # KBUILD_EXTMOD
1623 clean: $(clean-dirs)
1626 @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1627 \( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1629 -o -name '*.dtb' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1630 -o -name '*.dwo' -o -name '*.lst' \
1632 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1633 -o -name '*.lex.c' -o -name '*.tab.[ch]' \
1634 -o -name '*.asn1.[ch]' \
1635 -o -name '*.symtypes' -o -name 'modules.order' \
1636 -o -name modules.builtin -o -name '.tmp_*.o.*' \
1637 -o -name '*.c.[012]*.*' \
1639 -o -name '*.gcno' \) -type f -print | xargs rm -f
1641 # Generate tags for editors
1642 # ---------------------------------------------------------------------------
1643 quiet_cmd_tags = GEN $@
1644 cmd_tags = $(CONFIG_SHELL) $(srctree)/scripts/tags.sh $@
1646 tags TAGS cscope gtags: FORCE
1649 # Scripts to check various things for consistency
1650 # ---------------------------------------------------------------------------
1652 PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1655 find $(srctree)/* $(RCS_FIND_IGNORE) \
1656 -name '*.[hcS]' -type f -print | sort \
1657 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1660 find $(srctree)/* $(RCS_FIND_IGNORE) \
1661 -name '*.[hcS]' -type f -print | sort \
1662 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1665 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/$@
1668 $(PERL) $(srctree)/scripts/namespace.pl
1671 $(PERL) $(srctree)/scripts/export_report.pl
1673 PHONY += checkstack kernelrelease kernelversion image_name
1675 # UML needs a little special treatment here. It wants to use the host
1676 # toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
1677 # else wants $(ARCH), including people doing cross-builds, which means
1678 # that $(SUBARCH) doesn't work here.
1680 CHECKSTACK_ARCH := $(SUBARCH)
1682 CHECKSTACK_ARCH := $(ARCH)
1685 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1686 $(PERL) $(src)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1689 @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1692 @echo $(KERNELVERSION)
1695 @echo $(KBUILD_IMAGE)
1697 # Clear a bunch of variables before executing the submake
1699 ifeq ($(quiet),silent_)
1704 $(Q)mkdir -p $(objtree)/tools
1705 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(src)/tools/
1708 $(Q)mkdir -p $(objtree)/tools
1709 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(src)/tools/ $*
1712 # ---------------------------------------------------------------------------
1713 # Single targets are compatible with:
1714 # - build with mixed source and output
1715 # - build with separate output dir 'make O=...'
1716 # - external modules
1718 # target-dir => where to store outputfile
1719 # build-dir => directory in kernel source tree to use
1721 build-target = $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD)/)$@
1722 build-dir = $(patsubst %/,%,$(dir $(build-target)))
1725 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1727 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1728 %.lst: prepare FORCE
1729 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1731 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1733 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1734 %.symtypes: prepare FORCE
1735 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1737 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1743 # Make sure the latest headers are built for Documentation
1744 Documentation/ samples/: headers_install
1746 $(Q)$(MAKE) KBUILD_MODULES=1 $(build)=$(build-dir)
1748 # FIXME Should go into a make.lib or something
1749 # ===========================================================================
1751 quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN $(wildcard $(rm-dirs)))
1752 cmd_rmdirs = rm -rf $(rm-dirs)
1754 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
1755 cmd_rmfiles = rm -f $(rm-files)
1757 # Run depmod only if we have System.map and depmod is executable
1758 quiet_cmd_depmod = DEPMOD $(KERNELRELEASE)
1759 cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1762 # Create temporary dir for module support files
1763 # clean it up only when building all modules
1764 cmd_crmodverdir = $(Q)mkdir -p $(MODVERDIR) \
1765 $(if $(KBUILD_MODULES),; rm -f $(MODVERDIR)/*)
1767 # read saved command lines for existing targets
1768 existing-targets := $(wildcard $(sort $(targets)))
1770 -include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
1772 endif # ifeq ($(config-targets),1)
1773 endif # ifeq ($(mixed-targets),1)
1774 endif # need-sub-make
1779 # Declare the contents of the PHONY variable as phony. We keep that
1780 # information in a variable so we can use it in if_changed and friends.