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 $(Q)rm -f .tmp_quiet_recordmcount
480 # To avoid any implicit rule to kick in, define an empty command.
481 scripts/basic/%: scripts_basic ;
483 PHONY += outputmakefile
484 # outputmakefile generates a Makefile in the output directory, if using a
485 # separate output directory. This allows convenient use of make in the
487 # At the same time when output Makefile generated, generate .gitignore to
488 # ignore whole output directory
490 ifneq ($(KBUILD_SRC),)
491 $(Q)ln -fsn $(srctree) source
492 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile $(srctree)
493 $(Q){ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
496 ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),)
497 ifneq ($(CROSS_COMPILE),)
498 CLANG_FLAGS := --target=$(notdir $(CROSS_COMPILE:%-=%))
499 GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
500 CLANG_FLAGS += --prefix=$(GCC_TOOLCHAIN_DIR)
501 GCC_TOOLCHAIN := $(realpath $(GCC_TOOLCHAIN_DIR)/..)
503 ifneq ($(GCC_TOOLCHAIN),)
504 CLANG_FLAGS += --gcc-toolchain=$(GCC_TOOLCHAIN)
506 CLANG_FLAGS += -no-integrated-as
507 KBUILD_CFLAGS += $(CLANG_FLAGS)
508 KBUILD_AFLAGS += $(CLANG_FLAGS)
512 RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
513 RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
514 RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
515 RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
516 RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
517 RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
518 export RETPOLINE_CFLAGS
519 export RETPOLINE_VDSO_CFLAGS
521 # The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
522 # Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
523 # CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
524 # and from include/config/auto.conf.cmd to detect the compiler upgrade.
525 CC_VERSION_TEXT = $(shell $(CC) --version | head -n 1)
527 ifeq ($(config-targets),1)
528 # ===========================================================================
529 # *config targets only - make sure prerequisites are updated, and descend
530 # in scripts/kconfig to make the *config target
532 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
533 # KBUILD_DEFCONFIG may point out an alternative default configuration
534 # used for 'make defconfig'
535 include arch/$(SRCARCH)/Makefile
536 export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
538 config: scripts_basic outputmakefile FORCE
539 $(Q)$(MAKE) $(build)=scripts/kconfig $@
541 %config: scripts_basic outputmakefile FORCE
542 $(Q)$(MAKE) $(build)=scripts/kconfig $@
545 # ===========================================================================
546 # Build targets only - this includes vmlinux, arch specific targets, clean
547 # targets and others. In general all targets except *config targets.
549 # If building an external module we do not care about the all: rule
550 # but instead _all depend on modules
552 ifeq ($(KBUILD_EXTMOD),)
558 # Decide whether to build built-in, modular, or both.
559 # Normally, just do built-in.
564 # If we have only "make modules", don't compile built-in objects.
565 # When we're building modules with modversions, we need to consider
566 # the built-in objects during the descend as well, in order to
567 # make sure the checksums are up to date before we record them.
569 ifeq ($(MAKECMDGOALS),modules)
570 KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
573 # If we have "make <whatever> modules", compile modules
574 # in addition to whatever we do anyway.
575 # Just "make" or "make all" shall build modules as well
577 ifneq ($(filter all _all modules,$(MAKECMDGOALS)),)
581 ifeq ($(MAKECMDGOALS),)
585 export KBUILD_MODULES KBUILD_BUILTIN
587 ifeq ($(KBUILD_EXTMOD),)
588 # Objects we will link into vmlinux / subdirs we need to visit
590 drivers-y := drivers/ sound/ firmware/
595 endif # KBUILD_EXTMOD
597 ifeq ($(dot-config),1)
598 include include/config/auto.conf
601 # The all: target is the default when no target is given on the
603 # This allow a user to issue only 'make' to build a kernel including modules
604 # Defaults to vmlinux, but the arch makefile usually adds further targets
607 CFLAGS_GCOV := -fprofile-arcs -ftest-coverage \
608 $(call cc-option,-fno-tree-loop-im) \
609 $(call cc-disable-warning,maybe-uninitialized,)
612 # The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
613 ifdef CONFIG_FUNCTION_TRACER
614 CC_FLAGS_FTRACE := -pg
617 # The arch Makefile can set ARCH_{CPP,A,C}FLAGS to override the default
618 # values of the respective KBUILD_* variables
622 include arch/$(SRCARCH)/Makefile
624 ifeq ($(dot-config),1)
625 ifeq ($(may-sync-config),1)
626 # Read in dependencies to all Kconfig* files, make sure to run syncconfig if
627 # changes are detected. This should be included after arch/$(SRCARCH)/Makefile
628 # because some architectures define CROSS_COMPILE there.
629 -include include/config/auto.conf.cmd
633 @echo >&2 '*** Configuration file "$@" not found!'
635 @echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
636 @echo >&2 '*** "make menuconfig" or "make xconfig").'
640 # The actual configuration files used during the build are stored in
641 # include/generated/ and include/config/. Update them if .config is newer than
642 # include/config/auto.conf (which mirrors .config).
644 # This exploits the 'multi-target pattern rule' trick.
645 # The syncconfig should be executed only once to make all the targets.
646 %/auto.conf %/auto.conf.cmd %/tristate.conf: $(KCONFIG_CONFIG)
647 $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
649 # External modules and some install targets need include/generated/autoconf.h
650 # and include/config/auto.conf but do not care if they are up-to-date.
651 # Use auto.conf to trigger the test
652 PHONY += include/config/auto.conf
654 include/config/auto.conf:
655 $(Q)test -e include/generated/autoconf.h -a -e $@ || ( \
657 echo >&2 " ERROR: Kernel configuration is invalid."; \
658 echo >&2 " include/generated/autoconf.h or $@ are missing.";\
659 echo >&2 " Run 'make oldconfig && make prepare' on kernel src to fix it."; \
663 endif # may-sync-config
664 endif # $(dot-config)
666 KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,)
667 KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,)
668 KBUILD_CFLAGS += $(call cc-disable-warning, format-truncation)
669 KBUILD_CFLAGS += $(call cc-disable-warning, format-overflow)
670 KBUILD_CFLAGS += $(call cc-disable-warning, int-in-bool-context)
672 ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
673 KBUILD_CFLAGS += $(call cc-option,-Oz,-Os)
678 ifdef CONFIG_CC_DISABLE_WARN_MAYBE_UNINITIALIZED
679 KBUILD_CFLAGS += -Wno-maybe-uninitialized
682 # Tell gcc to never replace conditional load with a non-conditional one
683 KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
685 include scripts/Makefile.kcov
686 include scripts/Makefile.gcc-plugins
688 ifdef CONFIG_READABLE_ASM
689 # Disable optimizations that make assembler listings hard to read.
690 # reorder blocks reorders the control in the function
691 # ipa clone creates specialized cloned functions
692 # partial inlining inlines only parts of functions
693 KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
694 $(call cc-option,-fno-ipa-cp-clone,) \
695 $(call cc-option,-fno-partial-inlining)
698 ifneq ($(CONFIG_FRAME_WARN),0)
699 KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
702 stackp-flags-$(CONFIG_CC_HAS_STACKPROTECTOR_NONE) := -fno-stack-protector
703 stackp-flags-$(CONFIG_STACKPROTECTOR) := -fstack-protector
704 stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG) := -fstack-protector-strong
706 KBUILD_CFLAGS += $(stackp-flags-y)
708 ifdef CONFIG_CC_IS_CLANG
709 KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
710 KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier)
711 KBUILD_CFLAGS += $(call cc-disable-warning, gnu)
712 KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
713 # Quiet clang warning: comparison of unsigned expression < 0 is always false
714 KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare)
715 # CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
716 # source of a reference will be _MergedGlobals and not on of the whitelisted names.
717 # See modpost pattern 2
718 KBUILD_CFLAGS += $(call cc-option, -mno-global-merge,)
719 KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior)
722 # These warnings generated too much noise in a regular build.
723 # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
724 KBUILD_CFLAGS += -Wno-unused-but-set-variable
727 KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
728 ifdef CONFIG_FRAME_POINTER
729 KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
731 # Some targets (ARM with Thumb2, for example), can't be built with frame
732 # pointers. For those, we don't have FUNCTION_TRACER automatically
733 # select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
734 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
735 # -fomit-frame-pointer with FUNCTION_TRACER.
736 ifndef CONFIG_FUNCTION_TRACER
737 KBUILD_CFLAGS += -fomit-frame-pointer
741 DEBUG_CFLAGS := $(call cc-option, -fno-var-tracking-assignments)
743 ifdef CONFIG_DEBUG_INFO
744 ifdef CONFIG_DEBUG_INFO_SPLIT
745 DEBUG_CFLAGS += $(call cc-option, -gsplit-dwarf, -g)
749 KBUILD_AFLAGS += -Wa,-gdwarf-2
751 ifdef CONFIG_DEBUG_INFO_DWARF4
752 DEBUG_CFLAGS += $(call cc-option, -gdwarf-4,)
755 ifdef CONFIG_DEBUG_INFO_REDUCED
756 DEBUG_CFLAGS += $(call cc-option, -femit-struct-debug-baseonly) \
757 $(call cc-option,-fno-var-tracking)
760 KBUILD_CFLAGS += $(DEBUG_CFLAGS)
763 ifdef CONFIG_FUNCTION_TRACER
764 ifdef CONFIG_FTRACE_MCOUNT_RECORD
765 # gcc 5 supports generating the mcount tables directly
766 ifeq ($(call cc-option-yn,-mrecord-mcount),y)
767 CC_FLAGS_FTRACE += -mrecord-mcount
768 export CC_USING_RECORD_MCOUNT := 1
770 ifdef CONFIG_HAVE_NOP_MCOUNT
771 ifeq ($(call cc-option-yn, -mnop-mcount),y)
772 CC_FLAGS_FTRACE += -mnop-mcount
773 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
777 ifdef CONFIG_HAVE_FENTRY
778 ifeq ($(call cc-option-yn, -mfentry),y)
779 CC_FLAGS_FTRACE += -mfentry
780 CC_FLAGS_USING += -DCC_USING_FENTRY
783 export CC_FLAGS_FTRACE
784 KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
785 KBUILD_AFLAGS += $(CC_FLAGS_USING)
786 ifdef CONFIG_DYNAMIC_FTRACE
787 ifdef CONFIG_HAVE_C_RECORDMCOUNT
788 BUILD_C_RECORDMCOUNT := y
789 export BUILD_C_RECORDMCOUNT
794 # We trigger additional mismatches with less inlining
795 ifdef CONFIG_DEBUG_SECTION_MISMATCH
796 KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
799 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
800 KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
801 LDFLAGS_vmlinux += --gc-sections
804 # arch Makefile may override CC so keep this after arch Makefile is included
805 NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
807 # warn about C99 declaration after statement
808 KBUILD_CFLAGS += -Wdeclaration-after-statement
810 # Variable Length Arrays (VLAs) should not be used anywhere in the kernel
811 KBUILD_CFLAGS += $(call cc-option,-Wvla)
813 # disable pointer signed / unsigned warnings in gcc 4.0
814 KBUILD_CFLAGS += -Wno-pointer-sign
816 # disable stringop warnings in gcc 8+
817 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
819 # disable invalid "can't wrap" optimizations for signed / pointers
820 KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow)
822 # clang sets -fmerge-all-constants by default as optimization, but this
823 # is non-conforming behavior for C and in fact breaks the kernel, so we
824 # need to disable it here generally.
825 KBUILD_CFLAGS += $(call cc-option,-fno-merge-all-constants)
827 # for gcc -fno-merge-all-constants disables everything, but it is fine
828 # to have actual conforming behavior enabled.
829 KBUILD_CFLAGS += $(call cc-option,-fmerge-constants)
831 # Make sure -fstack-check isn't enabled (like gentoo apparently did)
832 KBUILD_CFLAGS += $(call cc-option,-fno-stack-check,)
834 # conserve stack if available
835 KBUILD_CFLAGS += $(call cc-option,-fconserve-stack)
837 # Prohibit date/time macros, which would make the build non-deterministic
838 KBUILD_CFLAGS += $(call cc-option,-Werror=date-time)
840 # enforce correct pointer usage
841 KBUILD_CFLAGS += $(call cc-option,-Werror=incompatible-pointer-types)
843 # Require designated initializers for all marked structures
844 KBUILD_CFLAGS += $(call cc-option,-Werror=designated-init)
846 # change __FILE__ to the relative path from the srctree
847 KBUILD_CFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
849 # use the deterministic mode of AR if available
850 KBUILD_ARFLAGS := $(call ar-option,D)
852 include scripts/Makefile.kasan
853 include scripts/Makefile.extrawarn
854 include scripts/Makefile.ubsan
856 # Add any arch overrides and user supplied CPPFLAGS, AFLAGS and CFLAGS as the
858 KBUILD_CPPFLAGS += $(ARCH_CPPFLAGS) $(KCPPFLAGS)
859 KBUILD_AFLAGS += $(ARCH_AFLAGS) $(KAFLAGS)
860 KBUILD_CFLAGS += $(ARCH_CFLAGS) $(KCFLAGS)
862 # Use --build-id when available.
863 LDFLAGS_BUILD_ID := $(call ld-option, --build-id)
864 KBUILD_LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID)
865 LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)
867 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
868 LDFLAGS_vmlinux += $(call ld-option, -X,)
871 # insure the checker run with the right endianness
872 CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
874 # the checker needs the correct machine size
875 CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
877 # Default kernel image to build when no specific target is given.
878 # KBUILD_IMAGE may be overruled on the command line or
879 # set in the environment
880 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
882 export KBUILD_IMAGE ?= vmlinux
885 # INSTALL_PATH specifies where to place the updated kernel and system map
886 # images. Default is /boot, but you can set it to other values
887 export INSTALL_PATH ?= /boot
890 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
891 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
892 # an argument if needed. Otherwise it defaults to the kernel install path
894 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
897 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
898 # relocations required by build roots. This is not defined in the
899 # makefile but the argument can be passed to make if needed.
902 MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
906 # INSTALL_MOD_STRIP, if defined, will cause modules to be
907 # stripped after they are installed. If INSTALL_MOD_STRIP is '1', then
908 # the default option --strip-debug will be used. Otherwise,
909 # INSTALL_MOD_STRIP value will be used as the options to the strip command.
911 ifdef INSTALL_MOD_STRIP
912 ifeq ($(INSTALL_MOD_STRIP),1)
913 mod_strip_cmd = $(STRIP) --strip-debug
915 mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
916 endif # INSTALL_MOD_STRIP=1
919 endif # INSTALL_MOD_STRIP
922 # CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
923 # after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
924 # or CONFIG_MODULE_COMPRESS_XZ.
926 mod_compress_cmd = true
927 ifdef CONFIG_MODULE_COMPRESS
928 ifdef CONFIG_MODULE_COMPRESS_GZIP
929 mod_compress_cmd = gzip -n -f
930 endif # CONFIG_MODULE_COMPRESS_GZIP
931 ifdef CONFIG_MODULE_COMPRESS_XZ
932 mod_compress_cmd = xz -f
933 endif # CONFIG_MODULE_COMPRESS_XZ
934 endif # CONFIG_MODULE_COMPRESS
935 export mod_compress_cmd
937 # Select initial ramdisk compression format, default is gzip(1).
938 # This shall be used by the dracut(8) tool while creating an initramfs image.
940 INITRD_COMPRESS-y := gzip
941 INITRD_COMPRESS-$(CONFIG_RD_BZIP2) := bzip2
942 INITRD_COMPRESS-$(CONFIG_RD_LZMA) := lzma
943 INITRD_COMPRESS-$(CONFIG_RD_XZ) := xz
944 INITRD_COMPRESS-$(CONFIG_RD_LZO) := lzo
945 INITRD_COMPRESS-$(CONFIG_RD_LZ4) := lz4
946 # do not export INITRD_COMPRESS, since we didn't actually
947 # choose a sane default compression above.
948 # export INITRD_COMPRESS := $(INITRD_COMPRESS-y)
950 ifdef CONFIG_MODULE_SIG_ALL
951 $(eval $(call config_filename,MODULE_SIG_KEY))
953 mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
959 ifdef CONFIG_STACK_VALIDATION
960 has_libelf := $(call try-run,\
961 echo "int main() {}" | $(HOSTCC) -xc -o /dev/null -lelf -,1,0)
962 ifeq ($(has_libelf),1)
963 objtool_target := tools/objtool FORCE
965 SKIP_STACK_VALIDATION := 1
966 export SKIP_STACK_VALIDATION
972 ifeq ($(KBUILD_EXTMOD),)
973 core-y += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
975 vmlinux-dirs := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
976 $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
977 $(net-y) $(net-m) $(libs-y) $(libs-m) $(virt-y)))
979 vmlinux-alldirs := $(sort $(vmlinux-dirs) $(patsubst %/,%,$(filter %/, \
980 $(init-) $(core-) $(drivers-) $(net-) $(libs-) $(virt-))))
982 init-y := $(patsubst %/, %/built-in.a, $(init-y))
983 core-y := $(patsubst %/, %/built-in.a, $(core-y))
984 drivers-y := $(patsubst %/, %/built-in.a, $(drivers-y))
985 net-y := $(patsubst %/, %/built-in.a, $(net-y))
986 libs-y1 := $(patsubst %/, %/lib.a, $(libs-y))
987 libs-y2 := $(patsubst %/, %/built-in.a, $(filter-out %.a, $(libs-y)))
988 virt-y := $(patsubst %/, %/built-in.a, $(virt-y))
990 # Externally visible symbols (used by link-vmlinux.sh)
991 export KBUILD_VMLINUX_OBJS := $(head-y) $(init-y) $(core-y) $(libs-y2) \
992 $(drivers-y) $(net-y) $(virt-y)
993 export KBUILD_VMLINUX_LIBS := $(libs-y1)
994 export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
995 export LDFLAGS_vmlinux
996 # used by scripts/package/Makefile
997 export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) arch Documentation include samples scripts tools)
999 vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
1001 # Recurse until adjust_autoksyms.sh is satisfied
1002 PHONY += autoksyms_recursive
1003 autoksyms_recursive: $(vmlinux-deps)
1004 ifdef CONFIG_TRIM_UNUSED_KSYMS
1005 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1006 "$(MAKE) -f $(srctree)/Makefile vmlinux"
1009 # For the kernel to actually contain only the needed exported symbols,
1010 # we have to build modules as well to determine what those symbols are.
1011 # (this can be evaluated only once include/config/auto.conf has been included)
1012 ifdef CONFIG_TRIM_UNUSED_KSYMS
1016 autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1019 $(Q)mkdir -p $(dir $@)
1022 ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1024 # Final link of vmlinux with optional arch pass after final link
1025 cmd_link-vmlinux = \
1026 $(CONFIG_SHELL) $< $(LD) $(KBUILD_LDFLAGS) $(LDFLAGS_vmlinux) ; \
1027 $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1029 vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1030 +$(call if_changed,link-vmlinux)
1034 # Build samples along the rest of the kernel. This needs headers_install.
1035 ifdef CONFIG_SAMPLES
1036 vmlinux-dirs += samples
1037 samples: headers_install
1040 # The actual objects are generated when descending,
1041 # make sure no implicit rule kicks in
1042 $(sort $(vmlinux-deps)): $(vmlinux-dirs) ;
1044 # Handle descending into subdirectories listed in $(vmlinux-dirs)
1045 # Preset locale variables to speed up the build process. Limit locale
1046 # tweaks to this spot to avoid wrong language settings when running
1047 # make menuconfig etc.
1048 # Error messages still appears in the original language
1050 PHONY += $(vmlinux-dirs)
1051 $(vmlinux-dirs): prepare
1052 $(Q)$(MAKE) $(build)=$@ need-builtin=1
1054 filechk_kernel.release = \
1055 echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1057 # Store (new) KERNELRELEASE string in include/config/kernel.release
1058 include/config/kernel.release: $(srctree)/Makefile FORCE
1059 $(call filechk,kernel.release)
1061 # Additional helpers built in scripts/
1062 # Carefully list dependencies so we do not try to build scripts twice
1065 scripts: scripts_basic scripts_dtc
1066 $(Q)$(MAKE) $(build)=$(@)
1068 # Things we need to do before we recursively start building the kernel
1069 # or the modules are listed in "prepare".
1070 # A multi level approach is used. prepareN is processed before prepareN-1.
1071 # archprepare is used in arch Makefiles and when processed asm symlink,
1072 # version.h and scripts_basic is processed / created.
1074 PHONY += prepare archprepare prepare1 prepare3
1076 # prepare3 is used to check if we are building in a separate output directory,
1078 # 1) Check that make has not been executed in the kernel src $(srctree)
1079 prepare3: include/config/kernel.release
1080 ifneq ($(KBUILD_SRC),)
1081 @$(kecho) ' Using $(srctree) as source for kernel'
1082 $(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \
1083 echo >&2 " $(srctree) is not clean, please run 'make mrproper'"; \
1084 echo >&2 " in the '$(srctree)' directory.";\
1089 prepare1: prepare3 outputmakefile asm-generic $(version_h) $(autoksyms_h) \
1090 include/generated/utsrelease.h
1093 archprepare: archheaders archscripts prepare1 scripts
1095 prepare0: archprepare
1096 $(Q)$(MAKE) $(build)=scripts/mod
1097 $(Q)$(MAKE) $(build)=.
1099 # All the preparing..
1100 prepare: prepare0 prepare-objtool
1102 # Support for using generic headers in asm-generic
1103 asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1105 PHONY += asm-generic uapi-asm-generic
1106 asm-generic: uapi-asm-generic
1107 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm
1109 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm
1111 PHONY += prepare-objtool
1112 prepare-objtool: $(objtool_target)
1113 ifeq ($(SKIP_STACK_VALIDATION),1)
1114 ifdef CONFIG_UNWINDER_ORC
1115 @echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1118 @echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1122 # Generate some files
1123 # ---------------------------------------------------------------------------
1125 # KERNELRELEASE can change from a few different places, meaning version.h
1126 # needs to be updated, so this check is forced on all builds
1129 define filechk_utsrelease.h
1130 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1131 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1134 echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1137 define filechk_version.h
1138 echo \#define LINUX_VERSION_CODE $(shell \
1139 expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1140 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))'
1144 $(call filechk,version.h)
1145 $(Q)rm -f $(old_version_h)
1147 include/generated/utsrelease.h: include/config/kernel.release FORCE
1148 $(call filechk,utsrelease.h)
1152 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1153 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1155 # ---------------------------------------------------------------------------
1158 #Default location for installed headers
1159 export INSTALL_HDR_PATH = $(objtree)/usr
1161 # If we do an all arch process set dst to include/arch-$(SRCARCH)
1162 hdr-dst = $(if $(KBUILD_HEADERS), dst=include/arch-$(SRCARCH), dst=include)
1164 PHONY += archheaders archscripts
1167 __headers: $(version_h) scripts_basic uapi-asm-generic archheaders archscripts
1168 $(Q)$(MAKE) $(build)=scripts build_unifdef
1170 PHONY += headers_install_all
1171 headers_install_all:
1172 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh install
1174 PHONY += headers_install
1175 headers_install: __headers
1176 $(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1177 $(error Headers not exportable for the $(SRCARCH) architecture))
1178 $(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include
1179 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi $(hdr-dst)
1181 PHONY += headers_check_all
1182 headers_check_all: headers_install_all
1183 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh check
1185 PHONY += headers_check
1186 headers_check: headers_install
1187 $(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include HDRCHECK=1
1188 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi $(hdr-dst) HDRCHECK=1
1190 ifdef CONFIG_HEADERS_CHECK
1194 # ---------------------------------------------------------------------------
1199 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1201 PHONY += kselftest-clean
1203 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests clean
1205 PHONY += kselftest-merge
1207 $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1208 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/kconfig/merge_config.sh \
1209 -m $(objtree)/.config \
1210 $(srctree)/tools/testing/selftests/*/config
1211 +$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1213 # ---------------------------------------------------------------------------
1216 ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1217 dtstree := arch/$(SRCARCH)/boot/dts
1222 %.dtb: prepare3 scripts_dtc
1223 $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1225 PHONY += dtbs dtbs_install dt_binding_check
1226 dtbs dtbs_check: prepare3 scripts_dtc
1227 $(Q)$(MAKE) $(build)=$(dtstree)
1229 dtbs_check: export CHECK_DTBS=1
1230 dtbs_check: dt_binding_check
1233 $(Q)$(MAKE) $(dtbinst)=$(dtstree)
1235 ifdef CONFIG_OF_EARLY_FLATTREE
1241 PHONY += scripts_dtc
1242 scripts_dtc: scripts_basic
1243 $(Q)$(MAKE) $(build)=scripts/dtc
1245 dt_binding_check: scripts_dtc
1246 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1248 # ---------------------------------------------------------------------------
1251 ifdef CONFIG_MODULES
1253 # By default, build modules as well
1259 # A module can be listed more than once in obj-m resulting in
1260 # duplicate lines in modules.order files. Those are removed
1261 # using awk while concatenating to the final file.
1264 modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux) modules.builtin
1265 $(Q)$(AWK) '!x[$$0]++' $(vmlinux-dirs:%=$(objtree)/%/modules.order) > $(objtree)/modules.order
1266 @$(kecho) ' Building modules, stage 2.';
1267 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1269 modules.builtin: $(vmlinux-dirs:%=%/modules.builtin)
1270 $(Q)$(AWK) '!x[$$0]++' $^ > $(objtree)/modules.builtin
1272 %/modules.builtin: include/config/auto.conf include/config/tristate.conf
1273 $(Q)$(MAKE) $(modbuiltin)=$*
1276 # Target to prepare building external modules
1277 PHONY += modules_prepare
1278 modules_prepare: prepare
1280 # Target to install modules
1281 PHONY += modules_install
1282 modules_install: _modinst_ _modinst_post
1286 @rm -rf $(MODLIB)/kernel
1287 @rm -f $(MODLIB)/source
1288 @mkdir -p $(MODLIB)/kernel
1289 @ln -s $(abspath $(srctree)) $(MODLIB)/source
1290 @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
1291 rm -f $(MODLIB)/build ; \
1292 ln -s $(CURDIR) $(MODLIB)/build ; \
1294 @cp -f $(objtree)/modules.order $(MODLIB)/
1295 @cp -f $(objtree)/modules.builtin $(MODLIB)/
1296 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1298 # This depmod is only for convenience to give the initial
1299 # boot a modules.dep even before / is mounted read-write. However the
1300 # boot script depmod is the master version.
1301 PHONY += _modinst_post
1302 _modinst_post: _modinst_
1305 ifeq ($(CONFIG_MODULE_SIG), y)
1306 PHONY += modules_sign
1308 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1311 else # CONFIG_MODULES
1313 # Modules not configured
1314 # ---------------------------------------------------------------------------
1316 PHONY += modules modules_install
1317 modules modules_install:
1319 @echo >&2 "The present kernel configuration has modules disabled."
1320 @echo >&2 "Type 'make config' and enable loadable module support."
1321 @echo >&2 "Then build a kernel with module support enabled."
1325 endif # CONFIG_MODULES
1328 # Cleaning is done on three levels.
1329 # make clean Delete most generated files
1330 # Leave enough to build external modules
1331 # make mrproper Delete the current configuration, and all generated files
1332 # make distclean Remove editor backup files, patch leftover files and the like
1334 # Directories & files removed with 'make clean'
1335 CLEAN_DIRS += $(MODVERDIR) include/ksym
1337 # Directories & files removed with 'make mrproper'
1338 MRPROPER_DIRS += include/config usr/include include/generated \
1339 arch/*/include/generated .tmp_objdiff
1340 MRPROPER_FILES += .config .config.old .version \
1341 Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS \
1342 signing_key.pem signing_key.priv signing_key.x509 \
1343 x509.genkey extra_certificates signing_key.x509.keyid \
1344 signing_key.x509.signer vmlinux-gdb.py
1346 # clean - Delete most, but leave enough to build external modules
1348 clean: rm-dirs := $(CLEAN_DIRS)
1349 clean: rm-files := $(CLEAN_FILES)
1350 clean-dirs := $(addprefix _clean_, . $(vmlinux-alldirs) Documentation samples)
1352 PHONY += $(clean-dirs) clean archclean vmlinuxclean
1354 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1357 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1358 $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1360 clean: archclean vmlinuxclean
1362 # mrproper - Delete all generated files, including .config
1364 mrproper: rm-dirs := $(wildcard $(MRPROPER_DIRS))
1365 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1366 mrproper-dirs := $(addprefix _mrproper_,scripts)
1368 PHONY += $(mrproper-dirs) mrproper
1370 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1372 mrproper: clean $(mrproper-dirs)
1381 @find $(srctree) $(RCS_FIND_IGNORE) \
1382 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1383 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1384 -o -name 'core' \) \
1385 -type f -print | xargs rm -f
1388 # Packaging of the kernel to various formats
1389 # ---------------------------------------------------------------------------
1390 package-dir := scripts/package
1393 $(Q)$(MAKE) $(build)=$(package-dir) $@
1394 %pkg: include/config/kernel.release FORCE
1395 $(Q)$(MAKE) $(build)=$(package-dir) $@
1398 # Brief documentation of the typical targets used
1399 # ---------------------------------------------------------------------------
1401 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1402 boards := $(sort $(notdir $(boards)))
1403 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1404 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1408 @echo 'Cleaning targets:'
1409 @echo ' clean - Remove most generated files but keep the config and'
1410 @echo ' enough build support to build external modules'
1411 @echo ' mrproper - Remove all generated files + config + various backup files'
1412 @echo ' distclean - mrproper + remove editor backup and patch files'
1414 @echo 'Configuration targets:'
1415 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1417 @echo 'Other generic targets:'
1418 @echo ' all - Build all targets marked with [*]'
1419 @echo '* vmlinux - Build the bare kernel'
1420 @echo '* modules - Build all modules'
1421 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1422 @echo ' dir/ - Build all files in dir and below'
1423 @echo ' dir/file.[ois] - Build specified target only'
1424 @echo ' dir/file.ll - Build the LLVM assembly file'
1425 @echo ' (requires compiler support for LLVM assembly generation)'
1426 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1427 @echo ' (requires a recent binutils and recent build (System.map))'
1428 @echo ' dir/file.ko - Build module including final link'
1429 @echo ' modules_prepare - Set up for building external modules'
1430 @echo ' tags/TAGS - Generate tags file for editors'
1431 @echo ' cscope - Generate cscope index'
1432 @echo ' gtags - Generate GNU GLOBAL index'
1433 @echo ' kernelrelease - Output the release version string (use with make -s)'
1434 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1435 @echo ' image_name - Output the image name (use with make -s)'
1436 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1437 echo ' (default: $(INSTALL_HDR_PATH))'; \
1439 @echo 'Static analysers:'
1440 @echo ' checkstack - Generate a list of stack hogs'
1441 @echo ' namespacecheck - Name space analysis on compiled kernel'
1442 @echo ' versioncheck - Sanity check on version.h usage'
1443 @echo ' includecheck - Check for duplicate included header files'
1444 @echo ' export_report - List the usages of all exported symbols'
1445 @echo ' headers_check - Sanity check on exported headers'
1446 @echo ' headerdep - Detect inclusion cycles in headers'
1447 @echo ' coccicheck - Check with Coccinelle'
1449 @echo 'Kernel selftest:'
1450 @echo ' kselftest - Build and run kernel selftest (run as root)'
1451 @echo ' Build, install, and boot kernel before'
1452 @echo ' running kselftest on it'
1453 @echo ' kselftest-clean - Remove all generated kselftest files'
1454 @echo ' kselftest-merge - Merge all the config dependencies of kselftest to existing'
1458 echo 'Devicetree:'; \
1459 echo '* dtbs - Build device tree blobs for enabled boards'; \
1460 echo ' dtbs_install - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1463 @echo 'Userspace tools targets:'
1464 @echo ' use "make tools/help"'
1465 @echo ' or "cd tools; make help"'
1467 @echo 'Kernel packaging:'
1468 @$(MAKE) $(build)=$(package-dir) help
1470 @echo 'Documentation targets:'
1471 @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1473 @echo 'Architecture specific targets ($(SRCARCH)):'
1474 @$(if $(archhelp),$(archhelp),\
1475 echo ' No architecture specific help defined for $(SRCARCH)')
1478 $(foreach b, $(boards), \
1479 printf " %-24s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1481 @$(if $(board-dirs), \
1482 $(foreach b, $(board-dirs), \
1483 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1484 printf " %-16s - Show all of the above\\n" help-boards; \
1487 @echo ' make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1488 @echo ' make V=2 [targets] 2 => give reason for rebuild of target'
1489 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1490 @echo ' make C=1 [targets] Check re-compiled c source with $$CHECK (sparse by default)'
1491 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1492 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1493 @echo ' make W=n [targets] Enable extra gcc checks, n=1,2,3 where'
1494 @echo ' 1: warnings which may be relevant and do not occur too often'
1495 @echo ' 2: warnings which occur quite often but may still be relevant'
1496 @echo ' 3: more obscure warnings, can most likely be ignored'
1497 @echo ' Multiple levels can be combined with W=12 or W=123'
1499 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1500 @echo 'For further info see the ./README file'
1503 help-board-dirs := $(addprefix help-,$(board-dirs))
1505 help-boards: $(help-board-dirs)
1507 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1509 $(help-board-dirs): help-%:
1510 @echo 'Architecture specific targets ($(SRCARCH) $*):'
1511 @$(if $(boards-per-dir), \
1512 $(foreach b, $(boards-per-dir), \
1513 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1517 # Documentation targets
1518 # ---------------------------------------------------------------------------
1519 DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1520 linkcheckdocs dochelp refcheckdocs
1521 PHONY += $(DOC_TARGETS)
1522 $(DOC_TARGETS): scripts_basic FORCE
1523 $(Q)$(MAKE) $(build)=Documentation $@
1526 # ---------------------------------------------------------------------------
1528 PHONY += scripts_gdb
1529 scripts_gdb: prepare
1530 $(Q)$(MAKE) $(build)=scripts/gdb
1531 $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1533 ifdef CONFIG_GDB_SCRIPTS
1537 else # KBUILD_EXTMOD
1540 # External module support.
1541 # When building external modules the kernel used as basis is considered
1542 # read-only, and no consistency checks are made and the make
1543 # system is not used on the basis kernel. If updates are required
1544 # in the basis kernel ordinary make commands (without M=...) must
1547 # The following are the only valid targets when building external
1549 # make M=dir clean Delete all automatically generated files
1550 # make M=dir modules Make all modules in specified dir
1551 # make M=dir Same as 'make M=dir modules'
1552 # make M=dir modules_install
1553 # Install the modules built in the module directory
1554 # Assumes install directory is already created
1556 # We are always building modules
1559 PHONY += $(objtree)/Module.symvers
1560 $(objtree)/Module.symvers:
1561 @test -e $(objtree)/Module.symvers || ( \
1563 echo " WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1564 echo " is missing; modules will have no dependencies and modversions."; \
1567 module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
1568 PHONY += $(module-dirs) modules
1569 $(module-dirs): prepare $(objtree)/Module.symvers
1570 $(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@)
1572 modules: $(module-dirs)
1573 @$(kecho) ' Building modules, stage 2.';
1574 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1576 PHONY += modules_install
1577 modules_install: _emodinst_ _emodinst_post
1579 install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1582 $(Q)mkdir -p $(MODLIB)/$(install-dir)
1583 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1585 PHONY += _emodinst_post
1586 _emodinst_post: _emodinst_
1589 clean-dirs := $(addprefix _clean_,$(KBUILD_EXTMOD))
1591 PHONY += $(clean-dirs) clean
1593 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1595 clean: rm-dirs := $(MODVERDIR)
1596 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers
1600 @echo ' Building external modules.'
1601 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1603 @echo ' modules - default target, build the module(s)'
1604 @echo ' modules_install - install the module'
1605 @echo ' clean - remove generated files in module directory only'
1611 endif # KBUILD_EXTMOD
1613 clean: $(clean-dirs)
1616 @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1617 \( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1619 -o -name '*.dtb' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1620 -o -name '*.dwo' -o -name '*.lst' \
1622 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1623 -o -name '*.lex.c' -o -name '*.tab.[ch]' \
1624 -o -name '*.asn1.[ch]' \
1625 -o -name '*.symtypes' -o -name 'modules.order' \
1626 -o -name modules.builtin -o -name '.tmp_*.o.*' \
1627 -o -name '*.c.[012]*.*' \
1629 -o -name '*.gcno' \) -type f -print | xargs rm -f
1631 # Generate tags for editors
1632 # ---------------------------------------------------------------------------
1633 quiet_cmd_tags = GEN $@
1634 cmd_tags = $(CONFIG_SHELL) $(srctree)/scripts/tags.sh $@
1636 tags TAGS cscope gtags: FORCE
1639 # Scripts to check various things for consistency
1640 # ---------------------------------------------------------------------------
1642 PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1645 find $(srctree)/* $(RCS_FIND_IGNORE) \
1646 -name '*.[hcS]' -type f -print | sort \
1647 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1650 find $(srctree)/* $(RCS_FIND_IGNORE) \
1651 -name '*.[hcS]' -type f -print | sort \
1652 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1655 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/$@
1658 $(PERL) $(srctree)/scripts/namespace.pl
1661 $(PERL) $(srctree)/scripts/export_report.pl
1663 PHONY += checkstack kernelrelease kernelversion image_name
1665 # UML needs a little special treatment here. It wants to use the host
1666 # toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
1667 # else wants $(ARCH), including people doing cross-builds, which means
1668 # that $(SUBARCH) doesn't work here.
1670 CHECKSTACK_ARCH := $(SUBARCH)
1672 CHECKSTACK_ARCH := $(ARCH)
1675 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1676 $(PERL) $(src)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1679 @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1682 @echo $(KERNELVERSION)
1685 @echo $(KBUILD_IMAGE)
1687 # Clear a bunch of variables before executing the submake
1689 ifeq ($(quiet),silent_)
1694 $(Q)mkdir -p $(objtree)/tools
1695 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(src)/tools/
1698 $(Q)mkdir -p $(objtree)/tools
1699 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(src)/tools/ $*
1702 # ---------------------------------------------------------------------------
1703 # Single targets are compatible with:
1704 # - build with mixed source and output
1705 # - build with separate output dir 'make O=...'
1706 # - external modules
1708 # target-dir => where to store outputfile
1709 # build-dir => directory in kernel source tree to use
1711 build-target = $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD)/)$@
1712 build-dir = $(patsubst %/,%,$(dir $(build-target)))
1715 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1717 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1718 %.lst: prepare FORCE
1719 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1721 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1723 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1724 %.symtypes: prepare FORCE
1725 $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1727 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1733 # Make sure the latest headers are built for Documentation
1734 Documentation/ samples/: headers_install
1736 $(Q)$(MAKE) KBUILD_MODULES=1 $(build)=$(build-dir)
1738 # FIXME Should go into a make.lib or something
1739 # ===========================================================================
1741 quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN $(wildcard $(rm-dirs)))
1742 cmd_rmdirs = rm -rf $(rm-dirs)
1744 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
1745 cmd_rmfiles = rm -f $(rm-files)
1747 # Run depmod only if we have System.map and depmod is executable
1748 quiet_cmd_depmod = DEPMOD $(KERNELRELEASE)
1749 cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1752 # Create temporary dir for module support files
1753 # clean it up only when building all modules
1754 cmd_crmodverdir = $(Q)mkdir -p $(MODVERDIR) \
1755 $(if $(KBUILD_MODULES),; rm -f $(MODVERDIR)/*)
1757 # read saved command lines for existing targets
1758 existing-targets := $(wildcard $(sort $(targets)))
1760 -include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
1762 endif # ifeq ($(config-targets),1)
1763 endif # ifeq ($(mixed-targets),1)
1764 endif # sub-make-done
1769 # Declare the contents of the PHONY variable as phony. We keep that
1770 # information in a variable so we can use it in if_changed and friends.