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 # 'MAKEFLAGS += -rR' does not become immediately effective for old
41 # GNU Make versions. Cancel implicit rules for this Makefile.
42 $(lastword $(MAKEFILE_LIST)): ;
44 # Avoid funny character set dependencies
48 export LC_COLLATE LC_NUMERIC
50 # Avoid interference with shell env settings
54 # ---------------------------------------------------------------------------
56 # Normally, we echo the whole command before executing it. By making
57 # that echo $($(quiet)$(cmd)), we now have the possibility to set
58 # $(quiet) to choose other forms of output instead, e.g.
60 # quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
61 # cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
63 # If $(quiet) is empty, the whole command will be printed.
64 # If it is set to "quiet_", only the short version will be printed.
65 # If it is set to "silent_", nothing will be printed at all, since
66 # the variable $(silent_cmd_cc_o_c) doesn't exist.
68 # A simple variant is to prefix commands with $(Q) - that's useful
69 # for commands that shall be hidden in non-verbose mode.
73 # If KBUILD_VERBOSE equals 0 then the above command will be hidden.
74 # If KBUILD_VERBOSE equals 1 then the above command is displayed.
76 # To put more focus on warnings, be less verbose as default
77 # Use 'make V=1' to see the full commands
79 ifeq ("$(origin V)", "command line")
86 ifeq ($(KBUILD_VERBOSE),1)
94 # If the user is running make -s (silent mode), suppress echoing of
97 ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
101 export quiet Q KBUILD_VERBOSE
103 # kbuild supports saving output files in a separate directory.
104 # To locate output files in a separate directory two syntaxes are supported.
105 # In both cases the working directory must be the root of the kernel src.
107 # Use "make O=dir/to/store/output/files/"
109 # 2) Set KBUILD_OUTPUT
110 # Set the environment variable KBUILD_OUTPUT to point to the directory
111 # where the output files shall be placed.
112 # export KBUILD_OUTPUT=dir/to/store/output/files/
115 # The O= assignment takes precedence over the KBUILD_OUTPUT environment
118 # KBUILD_SRC is not intended to be used by the regular user (for now),
119 # it is set on invocation of make with KBUILD_OUTPUT or O= specified.
121 # OK, Make called in directory where kernel src resides
122 # Do we want to locate output files in a separate directory?
123 ifeq ("$(origin O)", "command line")
124 KBUILD_OUTPUT := $(O)
127 ifneq ($(words $(subst :, ,$(CURDIR))), 1)
128 $(error main directory cannot contain spaces nor colons)
131 ifneq ($(KBUILD_OUTPUT),)
132 # check that the output directory actually exists
133 saved-output := $(KBUILD_OUTPUT)
134 KBUILD_OUTPUT := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) \
136 $(if $(KBUILD_OUTPUT),, \
137 $(error failed to create output directory "$(saved-output)"))
139 # Look for make include files relative to root of kernel src
141 # This does not become effective immediately because MAKEFLAGS is re-parsed
142 # once after the Makefile is read. It is OK since we are going to invoke
144 MAKEFLAGS += --include-dir=$(CURDIR)
148 # Do not print "Entering directory ..." at all for in-tree build.
149 MAKEFLAGS += --no-print-directory
151 endif # ifneq ($(KBUILD_OUTPUT),)
153 PHONY += $(MAKECMDGOALS) sub-make
155 $(filter-out _all sub-make $(CURDIR)/Makefile, $(MAKECMDGOALS)) _all: sub-make
158 # Invoke a second make in the output directory, passing relevant variables
160 $(Q)$(MAKE) sub-make-done=1 \
161 $(if $(KBUILD_OUTPUT),-C $(KBUILD_OUTPUT) KBUILD_SRC=$(CURDIR)) \
162 -f $(CURDIR)/Makefile $(filter-out _all sub-make,$(MAKECMDGOALS))
165 # We process the rest of the Makefile if this is the final invocation of make
167 # Do not print "Entering directory ...",
168 # but we want to display it when entering to the output directory
169 # so that IDEs/editors are able to understand relative filenames.
170 MAKEFLAGS += --no-print-directory
172 # Call a source code checker (by default, "sparse") as part of the
175 # Use 'make C=1' to enable checking of only re-compiled files.
176 # Use 'make C=2' to enable checking of *all* source files, regardless
177 # of whether they are re-compiled or not.
179 # See the file "Documentation/dev-tools/sparse.rst" for more details,
180 # including where to get the "sparse" utility.
182 ifeq ("$(origin C)", "command line")
183 KBUILD_CHECKSRC = $(C)
185 ifndef KBUILD_CHECKSRC
189 # Use make M=dir to specify directory of external module to build
190 # Old syntax make ... SUBDIRS=$PWD is still supported
191 # Setting the environment variable KBUILD_EXTMOD take precedence
193 $(warning ================= WARNING ================)
194 $(warning 'SUBDIRS' will be removed after Linux 5.3)
195 $(warning Please use 'M=' or 'KBUILD_EXTMOD' instead)
196 $(warning ==========================================)
197 KBUILD_EXTMOD ?= $(SUBDIRS)
200 ifeq ("$(origin M)", "command line")
201 KBUILD_EXTMOD := $(M)
204 ifeq ($(KBUILD_SRC),)
205 # building in the source tree
208 ifeq ($(KBUILD_SRC)/,$(dir $(CURDIR)))
209 # building in a subdirectory of the source tree
212 srctree := $(KBUILD_SRC)
216 export KBUILD_CHECKSRC KBUILD_EXTMOD KBUILD_SRC
224 export srctree objtree VPATH
226 # To make sure we do not include .config for any of the *config targets
227 # catch them early, and hand them over to scripts/kconfig/Makefile
228 # It is allowed to specify more targets when calling make, including
229 # mixing *config targets and build targets.
230 # For example 'make oldconfig all'.
231 # Detect when mixed targets is specified, and make a second invocation
232 # of make so .config is not included in this case either (for *config).
234 version_h := include/generated/uapi/linux/version.h
235 old_version_h := include/linux/version.h
237 clean-targets := %clean mrproper cleandocs
238 no-dot-config-targets := $(clean-targets) \
239 cscope gtags TAGS tags help% %docs check% coccicheck \
240 $(version_h) headers_% archheaders archscripts \
241 %asm-generic kernelversion %src-pkg
242 no-sync-config-targets := $(no-dot-config-targets) install %install \
250 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
251 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
256 ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
257 ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
262 ifneq ($(KBUILD_EXTMOD),)
266 ifeq ($(KBUILD_EXTMOD),)
267 ifneq ($(filter config %config,$(MAKECMDGOALS)),)
269 ifneq ($(words $(MAKECMDGOALS)),1)
275 # For "make -j clean all", "make -j mrproper defconfig all", etc.
276 ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
277 ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
282 # install and modules_install need also be processed one by one
283 ifneq ($(filter install,$(MAKECMDGOALS)),)
284 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
289 ifeq ($(mixed-targets),1)
290 # ===========================================================================
291 # We're called with mixed targets (*config and build targets).
292 # Handle them one by one.
294 PHONY += $(MAKECMDGOALS) __build_one_by_one
296 $(filter-out __build_one_by_one, $(MAKECMDGOALS)): __build_one_by_one
301 for i in $(MAKECMDGOALS); do \
302 $(MAKE) -f $(srctree)/Makefile $$i; \
307 include scripts/Kbuild.include
309 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
310 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
311 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
312 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
314 include scripts/subarch.include
316 # Cross compiling and selecting different set of gcc/bin-utils
317 # ---------------------------------------------------------------------------
319 # When performing cross compilation for other architectures ARCH shall be set
320 # to the target architecture. (See arch/* for the possibilities).
321 # ARCH can be set during invocation of make:
323 # Another way is to have ARCH set in the environment.
324 # The default ARCH is the host where make is executed.
326 # CROSS_COMPILE specify the prefix used for all executables used
327 # during compilation. Only gcc and related bin-utils executables
328 # are prefixed with $(CROSS_COMPILE).
329 # CROSS_COMPILE can be set on the command line
330 # make CROSS_COMPILE=ia64-linux-
331 # Alternatively CROSS_COMPILE can be set in the environment.
332 # Default value for CROSS_COMPILE is not to prefix executables
333 # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
336 # Architecture as present in compile.h
337 UTS_MACHINE := $(ARCH)
340 # Additional ARCH settings for x86
344 ifeq ($(ARCH),x86_64)
348 # Additional ARCH settings for sparc
349 ifeq ($(ARCH),sparc32)
352 ifeq ($(ARCH),sparc64)
356 # Additional ARCH settings for sh
361 KCONFIG_CONFIG ?= .config
362 export KCONFIG_CONFIG
364 # SHELL used by kbuild
365 CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
366 else if [ -x /bin/bash ]; then echo /bin/bash; \
367 else echo sh; fi ; fi)
369 HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
370 HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
371 HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
375 KBUILD_HOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 \
376 -fomit-frame-pointer -std=gnu89 $(HOST_LFS_CFLAGS) \
378 KBUILD_HOSTCXXFLAGS := -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
379 KBUILD_HOSTLDFLAGS := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
380 KBUILD_HOSTLDLIBS := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
382 # Make variables (CC, etc...)
383 AS = $(CROSS_COMPILE)as
384 LD = $(CROSS_COMPILE)ld
385 CC = $(CROSS_COMPILE)gcc
387 AR = $(CROSS_COMPILE)ar
388 NM = $(CROSS_COMPILE)nm
389 STRIP = $(CROSS_COMPILE)strip
390 OBJCOPY = $(CROSS_COMPILE)objcopy
391 OBJDUMP = $(CROSS_COMPILE)objdump
395 INSTALLKERNEL := installkernel
396 DEPMOD = /sbin/depmod
403 CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
404 -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
413 # Use USERINCLUDE when you must reference the UAPI directories only.
415 -I$(srctree)/arch/$(SRCARCH)/include/uapi \
416 -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
417 -I$(srctree)/include/uapi \
418 -I$(objtree)/include/generated/uapi \
419 -include $(srctree)/include/linux/kconfig.h
421 # Use LINUXINCLUDE when you must reference the include/ directory.
422 # Needed to be compatible with the O= option
424 -I$(srctree)/arch/$(SRCARCH)/include \
425 -I$(objtree)/arch/$(SRCARCH)/include/generated \
426 $(if $(KBUILD_SRC), -I$(srctree)/include) \
427 -I$(objtree)/include \
430 KBUILD_AFLAGS := -D__ASSEMBLY__ -fno-PIE
431 KBUILD_CFLAGS := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
432 -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
433 -Werror=implicit-function-declaration -Werror=implicit-int \
434 -Wno-format-security \
436 KBUILD_CPPFLAGS := -D__KERNEL__
437 KBUILD_AFLAGS_KERNEL :=
438 KBUILD_CFLAGS_KERNEL :=
439 KBUILD_AFLAGS_MODULE := -DMODULE
440 KBUILD_CFLAGS_MODULE := -DMODULE
441 KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
443 GCC_PLUGINS_CFLAGS :=
445 export ARCH SRCARCH CONFIG_SHELL HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE AS LD CC
446 export CPP AR NM STRIP OBJCOPY OBJDUMP KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS
447 export MAKE LEX YACC AWK INSTALLKERNEL PERL PYTHON PYTHON2 PYTHON3 UTS_MACHINE
448 export HOSTCXX KBUILD_HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
450 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
451 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
452 export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN
453 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
454 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
455 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
456 export KBUILD_ARFLAGS
458 # When compiling out-of-tree modules, put MODVERDIR in the module
459 # tree rather than in the kernel tree. The kernel tree might
461 export MODVERDIR := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_versions
463 # Files to ignore in find ... statements
465 export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o \
466 -name CVS -o -name .pc -o -name .hg -o -name .git \) \
468 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
469 --exclude CVS --exclude .pc --exclude .hg --exclude .git
471 # ===========================================================================
472 # Rules shared between *config targets and build targets
474 # Basic helpers built in scripts/basic/
475 PHONY += scripts_basic
477 $(Q)$(MAKE) $(build)=scripts/basic
478 $(Q)rm -f .tmp_quiet_recordmcount
480 PHONY += outputmakefile
481 # outputmakefile generates a Makefile in the output directory, if using a
482 # separate output directory. This allows convenient use of make in the
484 # At the same time when output Makefile generated, generate .gitignore to
485 # ignore whole output directory
487 ifneq ($(KBUILD_SRC),)
488 $(Q)ln -fsn $(srctree) source
489 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile $(srctree)
490 $(Q){ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
493 ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),)
494 ifneq ($(CROSS_COMPILE),)
495 CLANG_FLAGS := --target=$(notdir $(CROSS_COMPILE:%-=%))
496 GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
497 CLANG_FLAGS += --prefix=$(GCC_TOOLCHAIN_DIR)
498 GCC_TOOLCHAIN := $(realpath $(GCC_TOOLCHAIN_DIR)/..)
500 ifneq ($(GCC_TOOLCHAIN),)
501 CLANG_FLAGS += --gcc-toolchain=$(GCC_TOOLCHAIN)
503 CLANG_FLAGS += -no-integrated-as
504 KBUILD_CFLAGS += $(CLANG_FLAGS)
505 KBUILD_AFLAGS += $(CLANG_FLAGS)
509 RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
510 RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
511 RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
512 RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
513 RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
514 RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
515 export RETPOLINE_CFLAGS
516 export RETPOLINE_VDSO_CFLAGS
518 # The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
519 # Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
520 # CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
521 # and from include/config/auto.conf.cmd to detect the compiler upgrade.
522 CC_VERSION_TEXT = $(shell $(CC) --version | head -n 1)
524 ifeq ($(config-targets),1)
525 # ===========================================================================
526 # *config targets only - make sure prerequisites are updated, and descend
527 # in scripts/kconfig to make the *config target
529 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
530 # KBUILD_DEFCONFIG may point out an alternative default configuration
531 # used for 'make defconfig'
532 include arch/$(SRCARCH)/Makefile
533 export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
535 config: scripts_basic outputmakefile FORCE
536 $(Q)$(MAKE) $(build)=scripts/kconfig $@
538 %config: scripts_basic outputmakefile FORCE
539 $(Q)$(MAKE) $(build)=scripts/kconfig $@
542 # ===========================================================================
543 # Build targets only - this includes vmlinux, arch specific targets, clean
544 # targets and others. In general all targets except *config targets.
546 # If building an external module we do not care about the all: rule
547 # but instead _all depend on modules
549 ifeq ($(KBUILD_EXTMOD),)
555 # Decide whether to build built-in, modular, or both.
556 # Normally, just do built-in.
561 # If we have only "make modules", don't compile built-in objects.
562 # When we're building modules with modversions, we need to consider
563 # the built-in objects during the descend as well, in order to
564 # make sure the checksums are up to date before we record them.
566 ifeq ($(MAKECMDGOALS),modules)
567 KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
570 # If we have "make <whatever> modules", compile modules
571 # in addition to whatever we do anyway.
572 # Just "make" or "make all" shall build modules as well
574 ifneq ($(filter all _all modules,$(MAKECMDGOALS)),)
578 ifeq ($(MAKECMDGOALS),)
582 export KBUILD_MODULES KBUILD_BUILTIN
584 ifeq ($(KBUILD_EXTMOD),)
585 # Objects we will link into vmlinux / subdirs we need to visit
587 drivers-y := drivers/ sound/
592 endif # KBUILD_EXTMOD
594 ifeq ($(dot-config),1)
595 include include/config/auto.conf
598 # The all: target is the default when no target is given on the
600 # This allow a user to issue only 'make' to build a kernel including modules
601 # Defaults to vmlinux, but the arch makefile usually adds further targets
604 CFLAGS_GCOV := -fprofile-arcs -ftest-coverage \
605 $(call cc-option,-fno-tree-loop-im) \
606 $(call cc-disable-warning,maybe-uninitialized,)
609 # The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
610 ifdef CONFIG_FUNCTION_TRACER
611 CC_FLAGS_FTRACE := -pg
614 # The arch Makefile can set ARCH_{CPP,A,C}FLAGS to override the default
615 # values of the respective KBUILD_* variables
619 include arch/$(SRCARCH)/Makefile
621 ifeq ($(dot-config),1)
622 ifeq ($(may-sync-config),1)
623 # Read in dependencies to all Kconfig* files, make sure to run syncconfig if
624 # changes are detected. This should be included after arch/$(SRCARCH)/Makefile
625 # because some architectures define CROSS_COMPILE there.
626 -include include/config/auto.conf.cmd
630 @echo >&2 '*** Configuration file "$@" not found!'
632 @echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
633 @echo >&2 '*** "make menuconfig" or "make xconfig").'
637 # The actual configuration files used during the build are stored in
638 # include/generated/ and include/config/. Update them if .config is newer than
639 # include/config/auto.conf (which mirrors .config).
641 # This exploits the 'multi-target pattern rule' trick.
642 # The syncconfig should be executed only once to make all the targets.
643 %/auto.conf %/auto.conf.cmd %/tristate.conf: $(KCONFIG_CONFIG)
644 $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
646 # External modules and some install targets need include/generated/autoconf.h
647 # and include/config/auto.conf but do not care if they are up-to-date.
648 # Use auto.conf to trigger the test
649 PHONY += include/config/auto.conf
651 include/config/auto.conf:
652 $(Q)test -e include/generated/autoconf.h -a -e $@ || ( \
654 echo >&2 " ERROR: Kernel configuration is invalid."; \
655 echo >&2 " include/generated/autoconf.h or $@ are missing.";\
656 echo >&2 " Run 'make oldconfig && make prepare' on kernel src to fix it."; \
660 endif # may-sync-config
661 endif # $(dot-config)
663 KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,)
664 KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,)
665 KBUILD_CFLAGS += $(call cc-disable-warning, format-truncation)
666 KBUILD_CFLAGS += $(call cc-disable-warning, format-overflow)
667 KBUILD_CFLAGS += $(call cc-disable-warning, int-in-bool-context)
669 ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
670 KBUILD_CFLAGS += $(call cc-option,-Oz,-Os)
675 ifdef CONFIG_CC_DISABLE_WARN_MAYBE_UNINITIALIZED
676 KBUILD_CFLAGS += -Wno-maybe-uninitialized
679 # Tell gcc to never replace conditional load with a non-conditional one
680 KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
682 include scripts/Makefile.kcov
683 include scripts/Makefile.gcc-plugins
685 ifdef CONFIG_READABLE_ASM
686 # Disable optimizations that make assembler listings hard to read.
687 # reorder blocks reorders the control in the function
688 # ipa clone creates specialized cloned functions
689 # partial inlining inlines only parts of functions
690 KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
691 $(call cc-option,-fno-ipa-cp-clone,) \
692 $(call cc-option,-fno-partial-inlining)
695 ifneq ($(CONFIG_FRAME_WARN),0)
696 KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
699 stackp-flags-$(CONFIG_CC_HAS_STACKPROTECTOR_NONE) := -fno-stack-protector
700 stackp-flags-$(CONFIG_STACKPROTECTOR) := -fstack-protector
701 stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG) := -fstack-protector-strong
703 KBUILD_CFLAGS += $(stackp-flags-y)
705 ifdef CONFIG_CC_IS_CLANG
706 KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
707 KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier)
708 KBUILD_CFLAGS += $(call cc-disable-warning, gnu)
709 KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
710 # Quiet clang warning: comparison of unsigned expression < 0 is always false
711 KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare)
712 # CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
713 # source of a reference will be _MergedGlobals and not on of the whitelisted names.
714 # See modpost pattern 2
715 KBUILD_CFLAGS += $(call cc-option, -mno-global-merge,)
716 KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior)
719 # These warnings generated too much noise in a regular build.
720 # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
721 KBUILD_CFLAGS += -Wno-unused-but-set-variable
724 KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
725 ifdef CONFIG_FRAME_POINTER
726 KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
728 # Some targets (ARM with Thumb2, for example), can't be built with frame
729 # pointers. For those, we don't have FUNCTION_TRACER automatically
730 # select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
731 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
732 # -fomit-frame-pointer with FUNCTION_TRACER.
733 ifndef CONFIG_FUNCTION_TRACER
734 KBUILD_CFLAGS += -fomit-frame-pointer
738 DEBUG_CFLAGS := $(call cc-option, -fno-var-tracking-assignments)
740 ifdef CONFIG_DEBUG_INFO
741 ifdef CONFIG_DEBUG_INFO_SPLIT
742 DEBUG_CFLAGS += -gsplit-dwarf
746 KBUILD_AFLAGS += -Wa,-gdwarf-2
748 ifdef CONFIG_DEBUG_INFO_DWARF4
749 DEBUG_CFLAGS += -gdwarf-4
752 ifdef CONFIG_DEBUG_INFO_REDUCED
753 DEBUG_CFLAGS += $(call cc-option, -femit-struct-debug-baseonly) \
754 $(call cc-option,-fno-var-tracking)
757 KBUILD_CFLAGS += $(DEBUG_CFLAGS)
760 ifdef CONFIG_FUNCTION_TRACER
761 ifdef CONFIG_FTRACE_MCOUNT_RECORD
762 # gcc 5 supports generating the mcount tables directly
763 ifeq ($(call cc-option-yn,-mrecord-mcount),y)
764 CC_FLAGS_FTRACE += -mrecord-mcount
765 export CC_USING_RECORD_MCOUNT := 1
767 ifdef CONFIG_HAVE_NOP_MCOUNT
768 ifeq ($(call cc-option-yn, -mnop-mcount),y)
769 CC_FLAGS_FTRACE += -mnop-mcount
770 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
774 ifdef CONFIG_HAVE_FENTRY
775 ifeq ($(call cc-option-yn, -mfentry),y)
776 CC_FLAGS_FTRACE += -mfentry
777 CC_FLAGS_USING += -DCC_USING_FENTRY
780 export CC_FLAGS_FTRACE
781 KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
782 KBUILD_AFLAGS += $(CC_FLAGS_USING)
783 ifdef CONFIG_DYNAMIC_FTRACE
784 ifdef CONFIG_HAVE_C_RECORDMCOUNT
785 BUILD_C_RECORDMCOUNT := y
786 export BUILD_C_RECORDMCOUNT
791 # We trigger additional mismatches with less inlining
792 ifdef CONFIG_DEBUG_SECTION_MISMATCH
793 KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
796 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
797 KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
798 LDFLAGS_vmlinux += --gc-sections
801 # arch Makefile may override CC so keep this after arch Makefile is included
802 NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
804 # warn about C99 declaration after statement
805 KBUILD_CFLAGS += -Wdeclaration-after-statement
807 # Variable Length Arrays (VLAs) should not be used anywhere in the kernel
808 KBUILD_CFLAGS += $(call cc-option,-Wvla)
810 # disable pointer signed / unsigned warnings in gcc 4.0
811 KBUILD_CFLAGS += -Wno-pointer-sign
813 # disable stringop warnings in gcc 8+
814 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
816 # disable invalid "can't wrap" optimizations for signed / pointers
817 KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow)
819 # clang sets -fmerge-all-constants by default as optimization, but this
820 # is non-conforming behavior for C and in fact breaks the kernel, so we
821 # need to disable it here generally.
822 KBUILD_CFLAGS += $(call cc-option,-fno-merge-all-constants)
824 # for gcc -fno-merge-all-constants disables everything, but it is fine
825 # to have actual conforming behavior enabled.
826 KBUILD_CFLAGS += $(call cc-option,-fmerge-constants)
828 # Make sure -fstack-check isn't enabled (like gentoo apparently did)
829 KBUILD_CFLAGS += $(call cc-option,-fno-stack-check,)
831 # conserve stack if available
832 KBUILD_CFLAGS += $(call cc-option,-fconserve-stack)
834 # Prohibit date/time macros, which would make the build non-deterministic
835 KBUILD_CFLAGS += $(call cc-option,-Werror=date-time)
837 # enforce correct pointer usage
838 KBUILD_CFLAGS += $(call cc-option,-Werror=incompatible-pointer-types)
840 # Require designated initializers for all marked structures
841 KBUILD_CFLAGS += $(call cc-option,-Werror=designated-init)
843 # change __FILE__ to the relative path from the srctree
844 KBUILD_CFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
846 # use the deterministic mode of AR if available
847 KBUILD_ARFLAGS := $(call ar-option,D)
849 include scripts/Makefile.kasan
850 include scripts/Makefile.extrawarn
851 include scripts/Makefile.ubsan
853 # Add any arch overrides and user supplied CPPFLAGS, AFLAGS and CFLAGS as the
855 KBUILD_CPPFLAGS += $(ARCH_CPPFLAGS) $(KCPPFLAGS)
856 KBUILD_AFLAGS += $(ARCH_AFLAGS) $(KAFLAGS)
857 KBUILD_CFLAGS += $(ARCH_CFLAGS) $(KCFLAGS)
859 # Use --build-id when available.
860 LDFLAGS_BUILD_ID := $(call ld-option, --build-id)
861 KBUILD_LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID)
862 LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)
864 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
865 LDFLAGS_vmlinux += $(call ld-option, -X,)
868 # insure the checker run with the right endianness
869 CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
871 # the checker needs the correct machine size
872 CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
874 # Default kernel image to build when no specific target is given.
875 # KBUILD_IMAGE may be overruled on the command line or
876 # set in the environment
877 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
879 export KBUILD_IMAGE ?= vmlinux
882 # INSTALL_PATH specifies where to place the updated kernel and system map
883 # images. Default is /boot, but you can set it to other values
884 export INSTALL_PATH ?= /boot
887 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
888 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
889 # an argument if needed. Otherwise it defaults to the kernel install path
891 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
894 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
895 # relocations required by build roots. This is not defined in the
896 # makefile but the argument can be passed to make if needed.
899 MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
903 # INSTALL_MOD_STRIP, if defined, will cause modules to be
904 # stripped after they are installed. If INSTALL_MOD_STRIP is '1', then
905 # the default option --strip-debug will be used. Otherwise,
906 # INSTALL_MOD_STRIP value will be used as the options to the strip command.
908 ifdef INSTALL_MOD_STRIP
909 ifeq ($(INSTALL_MOD_STRIP),1)
910 mod_strip_cmd = $(STRIP) --strip-debug
912 mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
913 endif # INSTALL_MOD_STRIP=1
916 endif # INSTALL_MOD_STRIP
919 # CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
920 # after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
921 # or CONFIG_MODULE_COMPRESS_XZ.
923 mod_compress_cmd = true
924 ifdef CONFIG_MODULE_COMPRESS
925 ifdef CONFIG_MODULE_COMPRESS_GZIP
926 mod_compress_cmd = gzip -n -f
927 endif # CONFIG_MODULE_COMPRESS_GZIP
928 ifdef CONFIG_MODULE_COMPRESS_XZ
929 mod_compress_cmd = xz -f
930 endif # CONFIG_MODULE_COMPRESS_XZ
931 endif # CONFIG_MODULE_COMPRESS
932 export mod_compress_cmd
934 ifdef CONFIG_MODULE_SIG_ALL
935 $(eval $(call config_filename,MODULE_SIG_KEY))
937 mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
943 ifdef CONFIG_STACK_VALIDATION
944 has_libelf := $(call try-run,\
945 echo "int main() {}" | $(HOSTCC) -xc -o /dev/null -lelf -,1,0)
946 ifeq ($(has_libelf),1)
947 objtool_target := tools/objtool FORCE
949 SKIP_STACK_VALIDATION := 1
950 export SKIP_STACK_VALIDATION
956 ifeq ($(KBUILD_EXTMOD),)
957 core-y += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
959 vmlinux-dirs := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
960 $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
961 $(net-y) $(net-m) $(libs-y) $(libs-m) $(virt-y)))
963 vmlinux-alldirs := $(sort $(vmlinux-dirs) $(patsubst %/,%,$(filter %/, \
964 $(init-) $(core-) $(drivers-) $(net-) $(libs-) $(virt-))))
966 init-y := $(patsubst %/, %/built-in.a, $(init-y))
967 core-y := $(patsubst %/, %/built-in.a, $(core-y))
968 drivers-y := $(patsubst %/, %/built-in.a, $(drivers-y))
969 net-y := $(patsubst %/, %/built-in.a, $(net-y))
970 libs-y1 := $(patsubst %/, %/lib.a, $(libs-y))
971 libs-y2 := $(patsubst %/, %/built-in.a, $(filter-out %.a, $(libs-y)))
972 virt-y := $(patsubst %/, %/built-in.a, $(virt-y))
974 # Externally visible symbols (used by link-vmlinux.sh)
975 export KBUILD_VMLINUX_OBJS := $(head-y) $(init-y) $(core-y) $(libs-y2) \
976 $(drivers-y) $(net-y) $(virt-y)
977 export KBUILD_VMLINUX_LIBS := $(libs-y1)
978 export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
979 export LDFLAGS_vmlinux
980 # used by scripts/package/Makefile
981 export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) arch Documentation include samples scripts tools)
983 vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
985 # Recurse until adjust_autoksyms.sh is satisfied
986 PHONY += autoksyms_recursive
987 autoksyms_recursive: $(vmlinux-deps)
988 ifdef CONFIG_TRIM_UNUSED_KSYMS
989 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
990 "$(MAKE) -f $(srctree)/Makefile vmlinux"
993 # For the kernel to actually contain only the needed exported symbols,
994 # we have to build modules as well to determine what those symbols are.
995 # (this can be evaluated only once include/config/auto.conf has been included)
996 ifdef CONFIG_TRIM_UNUSED_KSYMS
1000 autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1003 $(Q)mkdir -p $(dir $@)
1006 ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1008 # Final link of vmlinux with optional arch pass after final link
1009 cmd_link-vmlinux = \
1010 $(CONFIG_SHELL) $< $(LD) $(KBUILD_LDFLAGS) $(LDFLAGS_vmlinux) ; \
1011 $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1013 vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1014 +$(call if_changed,link-vmlinux)
1018 # Build samples along the rest of the kernel. This needs headers_install.
1019 ifdef CONFIG_SAMPLES
1020 vmlinux-dirs += samples
1021 samples: headers_install
1024 # The actual objects are generated when descending,
1025 # make sure no implicit rule kicks in
1026 $(sort $(vmlinux-deps)): $(vmlinux-dirs) ;
1028 # Handle descending into subdirectories listed in $(vmlinux-dirs)
1029 # Preset locale variables to speed up the build process. Limit locale
1030 # tweaks to this spot to avoid wrong language settings when running
1031 # make menuconfig etc.
1032 # Error messages still appears in the original language
1034 PHONY += $(vmlinux-dirs)
1035 $(vmlinux-dirs): prepare
1036 $(Q)$(MAKE) $(build)=$@ need-builtin=1
1038 filechk_kernel.release = \
1039 echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1041 # Store (new) KERNELRELEASE string in include/config/kernel.release
1042 include/config/kernel.release: $(srctree)/Makefile FORCE
1043 $(call filechk,kernel.release)
1045 # Additional helpers built in scripts/
1046 # Carefully list dependencies so we do not try to build scripts twice
1049 scripts: scripts_basic scripts_dtc
1050 $(Q)$(MAKE) $(build)=$(@)
1052 # Things we need to do before we recursively start building the kernel
1053 # or the modules are listed in "prepare".
1054 # A multi level approach is used. prepareN is processed before prepareN-1.
1055 # archprepare is used in arch Makefiles and when processed asm symlink,
1056 # version.h and scripts_basic is processed / created.
1058 PHONY += prepare archprepare prepare1 prepare3
1060 # prepare3 is used to check if we are building in a separate output directory,
1062 # 1) Check that make has not been executed in the kernel src $(srctree)
1063 prepare3: include/config/kernel.release
1064 ifneq ($(KBUILD_SRC),)
1065 @$(kecho) ' Using $(srctree) as source for kernel'
1066 $(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \
1067 echo >&2 " $(srctree) is not clean, please run 'make mrproper'"; \
1068 echo >&2 " in the '$(srctree)' directory.";\
1073 prepare1: prepare3 outputmakefile asm-generic $(version_h) $(autoksyms_h) \
1074 include/generated/utsrelease.h
1077 archprepare: archheaders archscripts prepare1 scripts
1079 prepare0: archprepare
1080 $(Q)$(MAKE) $(build)=scripts/mod
1081 $(Q)$(MAKE) $(build)=.
1083 # All the preparing..
1084 prepare: prepare0 prepare-objtool
1086 # Support for using generic headers in asm-generic
1087 asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1089 PHONY += asm-generic uapi-asm-generic
1090 asm-generic: uapi-asm-generic
1091 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm
1093 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm
1095 PHONY += prepare-objtool
1096 prepare-objtool: $(objtool_target)
1097 ifeq ($(SKIP_STACK_VALIDATION),1)
1098 ifdef CONFIG_UNWINDER_ORC
1099 @echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1102 @echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1106 # Generate some files
1107 # ---------------------------------------------------------------------------
1109 # KERNELRELEASE can change from a few different places, meaning version.h
1110 # needs to be updated, so this check is forced on all builds
1113 define filechk_utsrelease.h
1114 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1115 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1118 echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1121 define filechk_version.h
1122 echo \#define LINUX_VERSION_CODE $(shell \
1123 expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1124 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))'
1128 $(call filechk,version.h)
1129 $(Q)rm -f $(old_version_h)
1131 include/generated/utsrelease.h: include/config/kernel.release FORCE
1132 $(call filechk,utsrelease.h)
1136 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1137 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1139 # ---------------------------------------------------------------------------
1142 #Default location for installed headers
1143 export INSTALL_HDR_PATH = $(objtree)/usr
1145 # If we do an all arch process set dst to include/arch-$(SRCARCH)
1146 hdr-dst = $(if $(KBUILD_HEADERS), dst=include/arch-$(SRCARCH), dst=include)
1148 PHONY += archheaders archscripts
1151 __headers: $(version_h) scripts_basic uapi-asm-generic archheaders archscripts
1152 $(Q)$(MAKE) $(build)=scripts build_unifdef
1154 PHONY += headers_install_all
1155 headers_install_all:
1156 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh install
1158 PHONY += headers_install
1159 headers_install: __headers
1160 $(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1161 $(error Headers not exportable for the $(SRCARCH) architecture))
1162 $(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include
1163 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi $(hdr-dst)
1165 PHONY += headers_check_all
1166 headers_check_all: headers_install_all
1167 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh check
1169 PHONY += headers_check
1170 headers_check: headers_install
1171 $(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include HDRCHECK=1
1172 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi $(hdr-dst) HDRCHECK=1
1174 ifdef CONFIG_HEADERS_CHECK
1178 # ---------------------------------------------------------------------------
1183 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1185 PHONY += kselftest-clean
1187 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests clean
1189 PHONY += kselftest-merge
1191 $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1192 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/kconfig/merge_config.sh \
1193 -m $(objtree)/.config \
1194 $(srctree)/tools/testing/selftests/*/config
1195 +$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1197 # ---------------------------------------------------------------------------
1200 ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1201 dtstree := arch/$(SRCARCH)/boot/dts
1206 %.dtb: prepare3 scripts_dtc
1207 $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1209 PHONY += dtbs dtbs_install dt_binding_check
1210 dtbs dtbs_check: prepare3 scripts_dtc
1211 $(Q)$(MAKE) $(build)=$(dtstree)
1213 dtbs_check: export CHECK_DTBS=1
1214 dtbs_check: dt_binding_check
1217 $(Q)$(MAKE) $(dtbinst)=$(dtstree)
1219 ifdef CONFIG_OF_EARLY_FLATTREE
1225 PHONY += scripts_dtc
1226 scripts_dtc: scripts_basic
1227 $(Q)$(MAKE) $(build)=scripts/dtc
1229 dt_binding_check: scripts_dtc
1230 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1232 # ---------------------------------------------------------------------------
1235 ifdef CONFIG_MODULES
1237 # By default, build modules as well
1243 # A module can be listed more than once in obj-m resulting in
1244 # duplicate lines in modules.order files. Those are removed
1245 # using awk while concatenating to the final file.
1248 modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux) modules.builtin
1249 $(Q)$(AWK) '!x[$$0]++' $(vmlinux-dirs:%=$(objtree)/%/modules.order) > $(objtree)/modules.order
1250 @$(kecho) ' Building modules, stage 2.';
1251 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1253 modules.builtin: $(vmlinux-dirs:%=%/modules.builtin)
1254 $(Q)$(AWK) '!x[$$0]++' $^ > $(objtree)/modules.builtin
1256 %/modules.builtin: include/config/auto.conf include/config/tristate.conf
1257 $(Q)$(MAKE) $(modbuiltin)=$*
1260 # Target to prepare building external modules
1261 PHONY += modules_prepare
1262 modules_prepare: prepare
1264 # Target to install modules
1265 PHONY += modules_install
1266 modules_install: _modinst_ _modinst_post
1270 @rm -rf $(MODLIB)/kernel
1271 @rm -f $(MODLIB)/source
1272 @mkdir -p $(MODLIB)/kernel
1273 @ln -s $(abspath $(srctree)) $(MODLIB)/source
1274 @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
1275 rm -f $(MODLIB)/build ; \
1276 ln -s $(CURDIR) $(MODLIB)/build ; \
1278 @cp -f $(objtree)/modules.order $(MODLIB)/
1279 @cp -f $(objtree)/modules.builtin $(MODLIB)/
1280 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1282 # This depmod is only for convenience to give the initial
1283 # boot a modules.dep even before / is mounted read-write. However the
1284 # boot script depmod is the master version.
1285 PHONY += _modinst_post
1286 _modinst_post: _modinst_
1289 ifeq ($(CONFIG_MODULE_SIG), y)
1290 PHONY += modules_sign
1292 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1295 else # CONFIG_MODULES
1297 # Modules not configured
1298 # ---------------------------------------------------------------------------
1300 PHONY += modules modules_install
1301 modules modules_install:
1303 @echo >&2 "The present kernel configuration has modules disabled."
1304 @echo >&2 "Type 'make config' and enable loadable module support."
1305 @echo >&2 "Then build a kernel with module support enabled."
1309 endif # CONFIG_MODULES
1312 # Cleaning is done on three levels.
1313 # make clean Delete most generated files
1314 # Leave enough to build external modules
1315 # make mrproper Delete the current configuration, and all generated files
1316 # make distclean Remove editor backup files, patch leftover files and the like
1318 # Directories & files removed with 'make clean'
1319 CLEAN_DIRS += $(MODVERDIR) include/ksym
1321 # Directories & files removed with 'make mrproper'
1322 MRPROPER_DIRS += include/config usr/include include/generated \
1323 arch/*/include/generated .tmp_objdiff
1324 MRPROPER_FILES += .config .config.old .version \
1325 Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS \
1326 signing_key.pem signing_key.priv signing_key.x509 \
1327 x509.genkey extra_certificates signing_key.x509.keyid \
1328 signing_key.x509.signer vmlinux-gdb.py
1330 # clean - Delete most, but leave enough to build external modules
1332 clean: rm-dirs := $(CLEAN_DIRS)
1333 clean: rm-files := $(CLEAN_FILES)
1334 clean-dirs := $(addprefix _clean_, . $(vmlinux-alldirs) Documentation samples)
1336 PHONY += $(clean-dirs) clean archclean vmlinuxclean
1338 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1341 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1342 $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1344 clean: archclean vmlinuxclean
1346 # mrproper - Delete all generated files, including .config
1348 mrproper: rm-dirs := $(wildcard $(MRPROPER_DIRS))
1349 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1350 mrproper-dirs := $(addprefix _mrproper_,scripts)
1352 PHONY += $(mrproper-dirs) mrproper
1354 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1356 mrproper: clean $(mrproper-dirs)
1365 @find $(srctree) $(RCS_FIND_IGNORE) \
1366 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1367 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1368 -o -name 'core' \) \
1369 -type f -print | xargs rm -f
1372 # Packaging of the kernel to various formats
1373 # ---------------------------------------------------------------------------
1374 package-dir := scripts/package
1377 $(Q)$(MAKE) $(build)=$(package-dir) $@
1378 %pkg: include/config/kernel.release FORCE
1379 $(Q)$(MAKE) $(build)=$(package-dir) $@
1382 # Brief documentation of the typical targets used
1383 # ---------------------------------------------------------------------------
1385 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1386 boards := $(sort $(notdir $(boards)))
1387 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1388 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1392 @echo 'Cleaning targets:'
1393 @echo ' clean - Remove most generated files but keep the config and'
1394 @echo ' enough build support to build external modules'
1395 @echo ' mrproper - Remove all generated files + config + various backup files'
1396 @echo ' distclean - mrproper + remove editor backup and patch files'
1398 @echo 'Configuration targets:'
1399 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1401 @echo 'Other generic targets:'
1402 @echo ' all - Build all targets marked with [*]'
1403 @echo '* vmlinux - Build the bare kernel'
1404 @echo '* modules - Build all modules'
1405 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1406 @echo ' dir/ - Build all files in dir and below'
1407 @echo ' dir/file.[ois] - Build specified target only'
1408 @echo ' dir/file.ll - Build the LLVM assembly file'
1409 @echo ' (requires compiler support for LLVM assembly generation)'
1410 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1411 @echo ' (requires a recent binutils and recent build (System.map))'
1412 @echo ' dir/file.ko - Build module including final link'
1413 @echo ' modules_prepare - Set up for building external modules'
1414 @echo ' tags/TAGS - Generate tags file for editors'
1415 @echo ' cscope - Generate cscope index'
1416 @echo ' gtags - Generate GNU GLOBAL index'
1417 @echo ' kernelrelease - Output the release version string (use with make -s)'
1418 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1419 @echo ' image_name - Output the image name (use with make -s)'
1420 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1421 echo ' (default: $(INSTALL_HDR_PATH))'; \
1423 @echo 'Static analysers:'
1424 @echo ' checkstack - Generate a list of stack hogs'
1425 @echo ' namespacecheck - Name space analysis on compiled kernel'
1426 @echo ' versioncheck - Sanity check on version.h usage'
1427 @echo ' includecheck - Check for duplicate included header files'
1428 @echo ' export_report - List the usages of all exported symbols'
1429 @echo ' headers_check - Sanity check on exported headers'
1430 @echo ' headerdep - Detect inclusion cycles in headers'
1431 @echo ' coccicheck - Check with Coccinelle'
1433 @echo 'Kernel selftest:'
1434 @echo ' kselftest - Build and run kernel selftest (run as root)'
1435 @echo ' Build, install, and boot kernel before'
1436 @echo ' running kselftest on it'
1437 @echo ' kselftest-clean - Remove all generated kselftest files'
1438 @echo ' kselftest-merge - Merge all the config dependencies of kselftest to existing'
1442 echo 'Devicetree:'; \
1443 echo '* dtbs - Build device tree blobs for enabled boards'; \
1444 echo ' dtbs_install - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1447 @echo 'Userspace tools targets:'
1448 @echo ' use "make tools/help"'
1449 @echo ' or "cd tools; make help"'
1451 @echo 'Kernel packaging:'
1452 @$(MAKE) $(build)=$(package-dir) help
1454 @echo 'Documentation targets:'
1455 @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1457 @echo 'Architecture specific targets ($(SRCARCH)):'
1458 @$(if $(archhelp),$(archhelp),\
1459 echo ' No architecture specific help defined for $(SRCARCH)')
1462 $(foreach b, $(boards), \
1463 printf " %-24s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1465 @$(if $(board-dirs), \
1466 $(foreach b, $(board-dirs), \
1467 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1468 printf " %-16s - Show all of the above\\n" help-boards; \
1471 @echo ' make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1472 @echo ' make V=2 [targets] 2 => give reason for rebuild of target'
1473 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1474 @echo ' make C=1 [targets] Check re-compiled c source with $$CHECK (sparse by default)'
1475 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1476 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1477 @echo ' make W=n [targets] Enable extra gcc checks, n=1,2,3 where'
1478 @echo ' 1: warnings which may be relevant and do not occur too often'
1479 @echo ' 2: warnings which occur quite often but may still be relevant'
1480 @echo ' 3: more obscure warnings, can most likely be ignored'
1481 @echo ' Multiple levels can be combined with W=12 or W=123'
1483 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1484 @echo 'For further info see the ./README file'
1487 help-board-dirs := $(addprefix help-,$(board-dirs))
1489 help-boards: $(help-board-dirs)
1491 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1493 $(help-board-dirs): help-%:
1494 @echo 'Architecture specific targets ($(SRCARCH) $*):'
1495 @$(if $(boards-per-dir), \
1496 $(foreach b, $(boards-per-dir), \
1497 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1501 # Documentation targets
1502 # ---------------------------------------------------------------------------
1503 DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1504 linkcheckdocs dochelp refcheckdocs
1505 PHONY += $(DOC_TARGETS)
1506 $(DOC_TARGETS): scripts_basic FORCE
1507 $(Q)$(MAKE) $(build)=Documentation $@
1510 # ---------------------------------------------------------------------------
1512 PHONY += scripts_gdb
1513 scripts_gdb: prepare
1514 $(Q)$(MAKE) $(build)=scripts/gdb
1515 $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1517 ifdef CONFIG_GDB_SCRIPTS
1521 else # KBUILD_EXTMOD
1524 # External module support.
1525 # When building external modules the kernel used as basis is considered
1526 # read-only, and no consistency checks are made and the make
1527 # system is not used on the basis kernel. If updates are required
1528 # in the basis kernel ordinary make commands (without M=...) must
1531 # The following are the only valid targets when building external
1533 # make M=dir clean Delete all automatically generated files
1534 # make M=dir modules Make all modules in specified dir
1535 # make M=dir Same as 'make M=dir modules'
1536 # make M=dir modules_install
1537 # Install the modules built in the module directory
1538 # Assumes install directory is already created
1540 # We are always building modules
1543 PHONY += $(objtree)/Module.symvers
1544 $(objtree)/Module.symvers:
1545 @test -e $(objtree)/Module.symvers || ( \
1547 echo " WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1548 echo " is missing; modules will have no dependencies and modversions."; \
1551 module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
1552 PHONY += $(module-dirs) modules
1553 $(module-dirs): prepare $(objtree)/Module.symvers
1554 $(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@)
1556 modules: $(module-dirs)
1557 @$(kecho) ' Building modules, stage 2.';
1558 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1560 PHONY += modules_install
1561 modules_install: _emodinst_ _emodinst_post
1563 install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1566 $(Q)mkdir -p $(MODLIB)/$(install-dir)
1567 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1569 PHONY += _emodinst_post
1570 _emodinst_post: _emodinst_
1573 clean-dirs := $(addprefix _clean_,$(KBUILD_EXTMOD))
1575 PHONY += $(clean-dirs) clean
1577 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1579 clean: rm-dirs := $(MODVERDIR)
1580 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers
1584 @echo ' Building external modules.'
1585 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1587 @echo ' modules - default target, build the module(s)'
1588 @echo ' modules_install - install the module'
1589 @echo ' clean - remove generated files in module directory only'
1595 endif # KBUILD_EXTMOD
1597 clean: $(clean-dirs)
1600 @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1601 \( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1603 -o -name '*.dtb' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1604 -o -name '*.dwo' -o -name '*.lst' \
1606 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1607 -o -name '*.lex.c' -o -name '*.tab.[ch]' \
1608 -o -name '*.asn1.[ch]' \
1609 -o -name '*.symtypes' -o -name 'modules.order' \
1610 -o -name modules.builtin -o -name '.tmp_*.o.*' \
1611 -o -name '*.c.[012]*.*' \
1613 -o -name '*.gcno' \) -type f -print | xargs rm -f
1615 # Generate tags for editors
1616 # ---------------------------------------------------------------------------
1617 quiet_cmd_tags = GEN $@
1618 cmd_tags = $(CONFIG_SHELL) $(srctree)/scripts/tags.sh $@
1620 tags TAGS cscope gtags: FORCE
1623 # Scripts to check various things for consistency
1624 # ---------------------------------------------------------------------------
1626 PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1629 find $(srctree)/* $(RCS_FIND_IGNORE) \
1630 -name '*.[hcS]' -type f -print | sort \
1631 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1634 find $(srctree)/* $(RCS_FIND_IGNORE) \
1635 -name '*.[hcS]' -type f -print | sort \
1636 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1639 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/$@
1642 $(PERL) $(srctree)/scripts/namespace.pl
1645 $(PERL) $(srctree)/scripts/export_report.pl
1647 PHONY += checkstack kernelrelease kernelversion image_name
1649 # UML needs a little special treatment here. It wants to use the host
1650 # toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
1651 # else wants $(ARCH), including people doing cross-builds, which means
1652 # that $(SUBARCH) doesn't work here.
1654 CHECKSTACK_ARCH := $(SUBARCH)
1656 CHECKSTACK_ARCH := $(ARCH)
1659 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1660 $(PERL) $(src)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1663 @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1666 @echo $(KERNELVERSION)
1669 @echo $(KBUILD_IMAGE)
1671 # Clear a bunch of variables before executing the submake
1673 ifeq ($(quiet),silent_)
1678 $(Q)mkdir -p $(objtree)/tools
1679 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(src)/tools/
1682 $(Q)mkdir -p $(objtree)/tools
1683 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(src)/tools/ $*
1686 # ---------------------------------------------------------------------------
1687 # Single targets are compatible with:
1688 # - build with mixed source and output
1689 # - build with separate output dir 'make O=...'
1690 # - external modules
1692 # target-dir => where to store outputfile
1693 # build-dir => directory in kernel source tree to use
1695 build-target = $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD)/)$@
1696 build-dir = $(patsubst %/,%,$(dir $(build-target)))
1699 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1701 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1702 %.lst: prepare FORCE
1703 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1705 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1707 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1708 %.symtypes: prepare FORCE
1709 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1711 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1717 # Make sure the latest headers are built for Documentation
1718 Documentation/ samples/: headers_install
1720 $(Q)$(MAKE) KBUILD_MODULES=1 $(build)=$(build-dir)
1722 # FIXME Should go into a make.lib or something
1723 # ===========================================================================
1725 quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN $(wildcard $(rm-dirs)))
1726 cmd_rmdirs = rm -rf $(rm-dirs)
1728 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
1729 cmd_rmfiles = rm -f $(rm-files)
1731 # Run depmod only if we have System.map and depmod is executable
1732 quiet_cmd_depmod = DEPMOD $(KERNELRELEASE)
1733 cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1736 # Create temporary dir for module support files
1737 # clean it up only when building all modules
1738 cmd_crmodverdir = $(Q)mkdir -p $(MODVERDIR) \
1739 $(if $(KBUILD_MODULES),; rm -f $(MODVERDIR)/*)
1741 # read saved command lines for existing targets
1742 existing-targets := $(wildcard $(sort $(targets)))
1744 -include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
1746 endif # ifeq ($(config-targets),1)
1747 endif # ifeq ($(mixed-targets),1)
1748 endif # sub-make-done
1753 # Declare the contents of the PHONY variable as phony. We keep that
1754 # information in a variable so we can use it in if_changed and friends.