1 # SPDX-License-Identifier: GPL-2.0
6 NAME = Kleptomaniac Octopus
9 # To see a list of typical targets execute "make help"
10 # More info can be located in ./README
11 # Comments in this file are targeted only to the developer, do not
12 # expect to learn how to build the kernel reading this file.
14 # That's our default target when none is given on the command line
18 # We are using a recursive build, so we need to do a little thinking
19 # to get the ordering right.
21 # Most importantly: sub-Makefiles should only ever modify files in
22 # their own directory. If in some directory we have a dependency on
23 # a file in another dir (which doesn't happen often, but it's often
24 # unavoidable when linking the built-in.a targets which finally
25 # turn into vmlinux), we will call a sub make in that other dir, and
26 # after that we are sure that everything which is in that other dir
29 # The only cases where we need to modify files which have global
30 # effects are thus separated out and done before the recursive
31 # descending is started. They are now explicitly listed as the
34 ifneq ($(sub_make_done),1)
36 # Do not use make's built-in rules and variables
37 # (this increases performance and avoids hard-to-debug behaviour)
40 # Avoid funny character set dependencies
44 export LC_COLLATE LC_NUMERIC
46 # Avoid interference with shell env settings
50 # ---------------------------------------------------------------------------
52 # Normally, we echo the whole command before executing it. By making
53 # that echo $($(quiet)$(cmd)), we now have the possibility to set
54 # $(quiet) to choose other forms of output instead, e.g.
56 # quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
57 # cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
59 # If $(quiet) is empty, the whole command will be printed.
60 # If it is set to "quiet_", only the short version will be printed.
61 # If it is set to "silent_", nothing will be printed at all, since
62 # the variable $(silent_cmd_cc_o_c) doesn't exist.
64 # A simple variant is to prefix commands with $(Q) - that's useful
65 # for commands that shall be hidden in non-verbose mode.
69 # If KBUILD_VERBOSE equals 0 then the above command will be hidden.
70 # If KBUILD_VERBOSE equals 1 then the above command is displayed.
71 # If KBUILD_VERBOSE equals 2 then give the reason why each target is rebuilt.
73 # To put more focus on warnings, be less verbose as default
74 # Use 'make V=1' to see the full commands
76 ifeq ("$(origin V)", "command line")
83 ifeq ($(KBUILD_VERBOSE),1)
91 # If the user is running make -s (silent mode), suppress echoing of
94 ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
98 export quiet Q KBUILD_VERBOSE
100 # Kbuild will save output files in the current working directory.
101 # This does not need to match to the root of the kernel source tree.
103 # For example, you can do this:
105 # cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
107 # If you want to save output files in a different location, there are
108 # two syntaxes to specify it.
111 # Use "make O=dir/to/store/output/files/"
113 # 2) Set KBUILD_OUTPUT
114 # Set the environment variable KBUILD_OUTPUT to point to the output directory.
115 # export KBUILD_OUTPUT=dir/to/store/output/files/; make
117 # The O= assignment takes precedence over the KBUILD_OUTPUT environment
120 # Do we want to change the working directory?
121 ifeq ("$(origin O)", "command line")
122 KBUILD_OUTPUT := $(O)
125 ifneq ($(KBUILD_OUTPUT),)
126 # Make's built-in functions such as $(abspath ...), $(realpath ...) cannot
127 # expand a shell special character '~'. We use a somewhat tedious way here.
128 abs_objtree := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) && pwd)
129 $(if $(abs_objtree),, \
130 $(error failed to create output directory "$(KBUILD_OUTPUT)"))
132 # $(realpath ...) resolves symlinks
133 abs_objtree := $(realpath $(abs_objtree))
135 abs_objtree := $(CURDIR)
136 endif # ifneq ($(KBUILD_OUTPUT),)
138 ifeq ($(abs_objtree),$(CURDIR))
139 # Suppress "Entering directory ..." unless we are changing the work directory.
140 MAKEFLAGS += --no-print-directory
145 abs_srctree := $(realpath $(dir $(lastword $(MAKEFILE_LIST))))
147 ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
148 $(error source directory cannot contain spaces or colons)
151 ifneq ($(abs_srctree),$(abs_objtree))
152 # Look for make include files relative to root of kernel src
154 # This does not become effective immediately because MAKEFLAGS is re-parsed
155 # once after the Makefile is read. We need to invoke sub-make.
156 MAKEFLAGS += --include-dir=$(abs_srctree)
160 ifneq ($(filter 3.%,$(MAKE_VERSION)),)
161 # 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
162 # We need to invoke sub-make to avoid implicit rules in the top Makefile.
164 # Cancel implicit rules for this Makefile.
165 $(lastword $(MAKEFILE_LIST)): ;
168 export abs_srctree abs_objtree
169 export sub_make_done := 1
171 ifeq ($(need-sub-make),1)
173 PHONY += $(MAKECMDGOALS) sub-make
175 $(filter-out _all sub-make $(lastword $(MAKEFILE_LIST)), $(MAKECMDGOALS)) _all: sub-make
178 # Invoke a second make in the output directory, passing relevant variables
180 $(Q)$(MAKE) -C $(abs_objtree) -f $(abs_srctree)/Makefile $(MAKECMDGOALS)
182 endif # need-sub-make
183 endif # sub_make_done
185 # We process the rest of the Makefile if this is the final invocation of make
186 ifeq ($(need-sub-make),)
188 # Do not print "Entering directory ...",
189 # but we want to display it when entering to the output directory
190 # so that IDEs/editors are able to understand relative filenames.
191 MAKEFLAGS += --no-print-directory
193 # Call a source code checker (by default, "sparse") as part of the
196 # Use 'make C=1' to enable checking of only re-compiled files.
197 # Use 'make C=2' to enable checking of *all* source files, regardless
198 # of whether they are re-compiled or not.
200 # See the file "Documentation/dev-tools/sparse.rst" for more details,
201 # including where to get the "sparse" utility.
203 ifeq ("$(origin C)", "command line")
204 KBUILD_CHECKSRC = $(C)
206 ifndef KBUILD_CHECKSRC
210 # Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
211 # directory of external module to build. Setting M= takes precedence.
212 ifeq ("$(origin M)", "command line")
213 KBUILD_EXTMOD := $(M)
216 export KBUILD_CHECKSRC KBUILD_EXTMOD
218 extmod-prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
220 ifeq ($(abs_srctree),$(abs_objtree))
221 # building in the source tree
223 building_out_of_srctree :=
225 ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
226 # building in a subdirectory of the source tree
229 srctree := $(abs_srctree)
231 building_out_of_srctree := 1
234 ifneq ($(KBUILD_ABS_SRCTREE),)
235 srctree := $(abs_srctree)
241 export building_out_of_srctree srctree objtree VPATH
243 # To make sure we do not include .config for any of the *config targets
244 # catch them early, and hand them over to scripts/kconfig/Makefile
245 # It is allowed to specify more targets when calling make, including
246 # mixing *config targets and build targets.
247 # For example 'make oldconfig all'.
248 # Detect when mixed targets is specified, and make a second invocation
249 # of make so .config is not included in this case either (for *config).
251 version_h := include/generated/uapi/linux/version.h
252 old_version_h := include/linux/version.h
254 clean-targets := %clean mrproper cleandocs
255 no-dot-config-targets := $(clean-targets) \
256 cscope gtags TAGS tags help% %docs check% coccicheck \
257 $(version_h) headers headers_% archheaders archscripts \
258 %asm-generic kernelversion %src-pkg dt_binding_check \
260 no-sync-config-targets := $(no-dot-config-targets) install %install \
262 single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
270 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
271 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
276 ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
277 ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
282 ifneq ($(KBUILD_EXTMOD),)
286 ifeq ($(KBUILD_EXTMOD),)
287 ifneq ($(filter config %config,$(MAKECMDGOALS)),)
289 ifneq ($(words $(MAKECMDGOALS)),1)
295 # We cannot build single targets and the others at the same time
296 ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
298 ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
303 # For "make -j clean all", "make -j mrproper defconfig all", etc.
304 ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
305 ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
310 # install and modules_install need also be processed one by one
311 ifneq ($(filter install,$(MAKECMDGOALS)),)
312 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
318 # ===========================================================================
319 # We're called with mixed targets (*config and build targets).
320 # Handle them one by one.
322 PHONY += $(MAKECMDGOALS) __build_one_by_one
324 $(filter-out __build_one_by_one, $(MAKECMDGOALS)): __build_one_by_one
329 for i in $(MAKECMDGOALS); do \
330 $(MAKE) -f $(srctree)/Makefile $$i; \
335 include scripts/Kbuild.include
337 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
338 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
339 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
340 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
342 include scripts/subarch.include
344 # Cross compiling and selecting different set of gcc/bin-utils
345 # ---------------------------------------------------------------------------
347 # When performing cross compilation for other architectures ARCH shall be set
348 # to the target architecture. (See arch/* for the possibilities).
349 # ARCH can be set during invocation of make:
351 # Another way is to have ARCH set in the environment.
352 # The default ARCH is the host where make is executed.
354 # CROSS_COMPILE specify the prefix used for all executables used
355 # during compilation. Only gcc and related bin-utils executables
356 # are prefixed with $(CROSS_COMPILE).
357 # CROSS_COMPILE can be set on the command line
358 # make CROSS_COMPILE=ia64-linux-
359 # Alternatively CROSS_COMPILE can be set in the environment.
360 # Default value for CROSS_COMPILE is not to prefix executables
361 # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
364 # Architecture as present in compile.h
365 UTS_MACHINE := $(ARCH)
368 # Additional ARCH settings for x86
372 ifeq ($(ARCH),x86_64)
376 # Additional ARCH settings for sparc
377 ifeq ($(ARCH),sparc32)
380 ifeq ($(ARCH),sparc64)
384 # Additional ARCH settings for sh
389 KCONFIG_CONFIG ?= .config
390 export KCONFIG_CONFIG
392 # Default file for 'make defconfig'. This may be overridden by arch-Makefile.
393 export KBUILD_DEFCONFIG := defconfig
395 # SHELL used by kbuild
398 HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
399 HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
400 HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
409 KBUILD_HOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 \
410 -fomit-frame-pointer -std=gnu89 $(HOST_LFS_CFLAGS) \
412 KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
413 KBUILD_HOSTLDFLAGS := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
414 KBUILD_HOSTLDLIBS := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
416 # Make variables (CC, etc...)
423 OBJCOPY = llvm-objcopy
424 OBJDUMP = llvm-objdump
425 READELF = llvm-readelf
429 CC = $(CROSS_COMPILE)gcc
430 LD = $(CROSS_COMPILE)ld
431 AR = $(CROSS_COMPILE)ar
432 NM = $(CROSS_COMPILE)nm
433 OBJCOPY = $(CROSS_COMPILE)objcopy
434 OBJDUMP = $(CROSS_COMPILE)objdump
435 READELF = $(CROSS_COMPILE)readelf
436 OBJSIZE = $(CROSS_COMPILE)size
437 STRIP = $(CROSS_COMPILE)strip
443 INSTALLKERNEL := installkernel
444 DEPMOD = /sbin/depmod
451 CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
452 -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
461 # Use USERINCLUDE when you must reference the UAPI directories only.
463 -I$(srctree)/arch/$(SRCARCH)/include/uapi \
464 -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
465 -I$(srctree)/include/uapi \
466 -I$(objtree)/include/generated/uapi \
467 -include $(srctree)/include/linux/kconfig.h
469 # Use LINUXINCLUDE when you must reference the include/ directory.
470 # Needed to be compatible with the O= option
472 -I$(srctree)/arch/$(SRCARCH)/include \
473 -I$(objtree)/arch/$(SRCARCH)/include/generated \
474 $(if $(building_out_of_srctree),-I$(srctree)/include) \
475 -I$(objtree)/include \
478 KBUILD_AFLAGS := -D__ASSEMBLY__ -fno-PIE
479 KBUILD_CFLAGS := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
480 -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
481 -Werror=implicit-function-declaration -Werror=implicit-int \
482 -Wno-format-security \
484 KBUILD_CPPFLAGS := -D__KERNEL__
485 KBUILD_AFLAGS_KERNEL :=
486 KBUILD_CFLAGS_KERNEL :=
487 KBUILD_AFLAGS_MODULE := -DMODULE
488 KBUILD_CFLAGS_MODULE := -DMODULE
489 KBUILD_LDFLAGS_MODULE :=
490 export KBUILD_LDS_MODULE := $(srctree)/scripts/module-common.lds
492 GCC_PLUGINS_CFLAGS :=
495 export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC
496 export CPP AR NM STRIP OBJCOPY OBJDUMP OBJSIZE READELF PAHOLE LEX YACC AWK INSTALLKERNEL
497 export PERL PYTHON PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
498 export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
500 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
501 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
502 export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN
503 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
504 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
505 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
507 # Files to ignore in find ... statements
509 export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o \
510 -name CVS -o -name .pc -o -name .hg -o -name .git \) \
512 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
513 --exclude CVS --exclude .pc --exclude .hg --exclude .git
515 # ===========================================================================
516 # Rules shared between *config targets and build targets
518 # Basic helpers built in scripts/basic/
519 PHONY += scripts_basic
521 $(Q)$(MAKE) $(build)=scripts/basic
522 $(Q)rm -f .tmp_quiet_recordmcount
524 PHONY += outputmakefile
525 # Before starting out-of-tree build, make sure the source tree is clean.
526 # outputmakefile generates a Makefile in the output directory, if using a
527 # separate output directory. This allows convenient use of make in the
529 # At the same time when output Makefile generated, generate .gitignore to
530 # ignore whole output directory
532 ifdef building_out_of_srctree
533 $(Q)if [ -f $(srctree)/.config -o \
534 -d $(srctree)/include/config -o \
535 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
537 echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
538 echo >&2 "*** in $(abs_srctree)";\
542 $(Q)ln -fsn $(srctree) source
543 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile $(srctree)
544 $(Q)test -e .gitignore || \
545 { echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
548 ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),)
549 ifneq ($(CROSS_COMPILE),)
550 CLANG_FLAGS += --target=$(notdir $(CROSS_COMPILE:%-=%))
551 GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
552 CLANG_FLAGS += --prefix=$(GCC_TOOLCHAIN_DIR)
553 GCC_TOOLCHAIN := $(realpath $(GCC_TOOLCHAIN_DIR)/..)
555 ifneq ($(GCC_TOOLCHAIN),)
556 CLANG_FLAGS += --gcc-toolchain=$(GCC_TOOLCHAIN)
558 ifneq ($(LLVM_IAS),1)
559 CLANG_FLAGS += -no-integrated-as
561 CLANG_FLAGS += -Werror=unknown-warning-option
562 KBUILD_CFLAGS += $(CLANG_FLAGS)
563 KBUILD_AFLAGS += $(CLANG_FLAGS)
567 # The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
568 # Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
569 # CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
570 # and from include/config/auto.conf.cmd to detect the compiler upgrade.
571 CC_VERSION_TEXT = $(shell $(CC) --version 2>/dev/null | head -n 1)
574 # ===========================================================================
575 # *config targets only - make sure prerequisites are updated, and descend
576 # in scripts/kconfig to make the *config target
578 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
579 # KBUILD_DEFCONFIG may point out an alternative default configuration
580 # used for 'make defconfig'
581 include arch/$(SRCARCH)/Makefile
582 export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
584 config: outputmakefile scripts_basic FORCE
585 $(Q)$(MAKE) $(build)=scripts/kconfig $@
587 %config: outputmakefile scripts_basic FORCE
588 $(Q)$(MAKE) $(build)=scripts/kconfig $@
591 # ===========================================================================
592 # Build targets only - this includes vmlinux, arch specific targets, clean
593 # targets and others. In general all targets except *config targets.
595 # If building an external module we do not care about the all: rule
596 # but instead _all depend on modules
598 ifeq ($(KBUILD_EXTMOD),)
604 # Decide whether to build built-in, modular, or both.
605 # Normally, just do built-in.
610 # If we have only "make modules", don't compile built-in objects.
611 # When we're building modules with modversions, we need to consider
612 # the built-in objects during the descend as well, in order to
613 # make sure the checksums are up to date before we record them.
615 ifeq ($(MAKECMDGOALS),modules)
616 KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
619 # If we have "make <whatever> modules", compile modules
620 # in addition to whatever we do anyway.
621 # Just "make" or "make all" shall build modules as well
623 ifneq ($(filter all _all modules nsdeps,$(MAKECMDGOALS)),)
627 ifeq ($(MAKECMDGOALS),)
631 export KBUILD_MODULES KBUILD_BUILTIN
634 include include/config/auto.conf
637 ifeq ($(KBUILD_EXTMOD),)
638 # Objects we will link into vmlinux / subdirs we need to visit
640 drivers-y := drivers/ sound/
641 drivers-$(CONFIG_SAMPLES) += samples/
646 endif # KBUILD_EXTMOD
648 # The all: target is the default when no target is given on the
650 # This allow a user to issue only 'make' to build a kernel including modules
651 # Defaults to vmlinux, but the arch makefile usually adds further targets
654 CFLAGS_GCOV := -fprofile-arcs -ftest-coverage \
655 $(call cc-option,-fno-tree-loop-im) \
656 $(call cc-disable-warning,maybe-uninitialized,)
659 # The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
660 ifdef CONFIG_FUNCTION_TRACER
661 CC_FLAGS_FTRACE := -pg
664 RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
665 RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
666 RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
667 RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
668 RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
669 RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
670 export RETPOLINE_CFLAGS
671 export RETPOLINE_VDSO_CFLAGS
673 include arch/$(SRCARCH)/Makefile
676 ifdef may-sync-config
677 # Read in dependencies to all Kconfig* files, make sure to run syncconfig if
678 # changes are detected. This should be included after arch/$(SRCARCH)/Makefile
679 # because some architectures define CROSS_COMPILE there.
680 include include/config/auto.conf.cmd
684 @echo >&2 '*** Configuration file "$@" not found!'
686 @echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
687 @echo >&2 '*** "make menuconfig" or "make xconfig").'
691 # The actual configuration files used during the build are stored in
692 # include/generated/ and include/config/. Update them if .config is newer than
693 # include/config/auto.conf (which mirrors .config).
695 # This exploits the 'multi-target pattern rule' trick.
696 # The syncconfig should be executed only once to make all the targets.
697 # (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
698 %/auto.conf %/auto.conf.cmd: $(KCONFIG_CONFIG)
699 $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
700 else # !may-sync-config
701 # External modules and some install targets need include/generated/autoconf.h
702 # and include/config/auto.conf but do not care if they are up-to-date.
703 # Use auto.conf to trigger the test
704 PHONY += include/config/auto.conf
706 include/config/auto.conf:
707 $(Q)test -e include/generated/autoconf.h -a -e $@ || ( \
709 echo >&2 " ERROR: Kernel configuration is invalid."; \
710 echo >&2 " include/generated/autoconf.h or $@ are missing.";\
711 echo >&2 " Run 'make oldconfig && make prepare' on kernel src to fix it."; \
715 endif # may-sync-config
718 KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,)
719 KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,)
720 KBUILD_CFLAGS += $(call cc-disable-warning, format-truncation)
721 KBUILD_CFLAGS += $(call cc-disable-warning, format-overflow)
722 KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
724 ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
726 else ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3
728 else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
732 # Tell gcc to never replace conditional load with a non-conditional one
733 KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
734 KBUILD_CFLAGS += $(call cc-option,-fno-allow-store-data-races)
736 include scripts/Makefile.kcov
737 include scripts/Makefile.gcc-plugins
739 ifdef CONFIG_READABLE_ASM
740 # Disable optimizations that make assembler listings hard to read.
741 # reorder blocks reorders the control in the function
742 # ipa clone creates specialized cloned functions
743 # partial inlining inlines only parts of functions
744 KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
745 $(call cc-option,-fno-ipa-cp-clone,) \
746 $(call cc-option,-fno-partial-inlining)
749 ifneq ($(CONFIG_FRAME_WARN),0)
750 KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
753 stackp-flags-$(CONFIG_CC_HAS_STACKPROTECTOR_NONE) := -fno-stack-protector
754 stackp-flags-$(CONFIG_STACKPROTECTOR) := -fstack-protector
755 stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG) := -fstack-protector-strong
757 KBUILD_CFLAGS += $(stackp-flags-y)
759 ifdef CONFIG_CC_IS_CLANG
760 KBUILD_CPPFLAGS += -Qunused-arguments
761 KBUILD_CFLAGS += -Wno-format-invalid-specifier
762 KBUILD_CFLAGS += -Wno-gnu
763 # CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
764 # source of a reference will be _MergedGlobals and not on of the whitelisted names.
765 # See modpost pattern 2
766 KBUILD_CFLAGS += -mno-global-merge
769 # These warnings generated too much noise in a regular build.
770 # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
771 KBUILD_CFLAGS += -Wno-unused-but-set-variable
773 # Warn about unmarked fall-throughs in switch statement.
774 # Disabled for clang while comment to attribute conversion happens and
775 # https://github.com/ClangBuiltLinux/linux/issues/636 is discussed.
776 KBUILD_CFLAGS += $(call cc-option,-Wimplicit-fallthrough,)
779 KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
780 ifdef CONFIG_FRAME_POINTER
781 KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
783 # Some targets (ARM with Thumb2, for example), can't be built with frame
784 # pointers. For those, we don't have FUNCTION_TRACER automatically
785 # select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
786 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
787 # -fomit-frame-pointer with FUNCTION_TRACER.
788 ifndef CONFIG_FUNCTION_TRACER
789 KBUILD_CFLAGS += -fomit-frame-pointer
793 # Initialize all stack variables with a pattern, if desired.
794 ifdef CONFIG_INIT_STACK_ALL
795 KBUILD_CFLAGS += -ftrivial-auto-var-init=pattern
798 DEBUG_CFLAGS := $(call cc-option, -fno-var-tracking-assignments)
800 ifdef CONFIG_DEBUG_INFO
801 ifdef CONFIG_DEBUG_INFO_SPLIT
802 DEBUG_CFLAGS += -gsplit-dwarf
806 KBUILD_AFLAGS += -Wa,-gdwarf-2
808 ifdef CONFIG_DEBUG_INFO_DWARF4
809 DEBUG_CFLAGS += -gdwarf-4
812 ifdef CONFIG_DEBUG_INFO_REDUCED
813 DEBUG_CFLAGS += $(call cc-option, -femit-struct-debug-baseonly) \
814 $(call cc-option,-fno-var-tracking)
817 KBUILD_CFLAGS += $(DEBUG_CFLAGS)
820 ifdef CONFIG_FUNCTION_TRACER
821 ifdef CONFIG_FTRACE_MCOUNT_RECORD
822 # gcc 5 supports generating the mcount tables directly
823 ifeq ($(call cc-option-yn,-mrecord-mcount),y)
824 CC_FLAGS_FTRACE += -mrecord-mcount
825 export CC_USING_RECORD_MCOUNT := 1
827 ifdef CONFIG_HAVE_NOP_MCOUNT
828 ifeq ($(call cc-option-yn, -mnop-mcount),y)
829 CC_FLAGS_FTRACE += -mnop-mcount
830 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
834 ifdef CONFIG_HAVE_FENTRY
835 ifeq ($(call cc-option-yn, -mfentry),y)
836 CC_FLAGS_FTRACE += -mfentry
837 CC_FLAGS_USING += -DCC_USING_FENTRY
840 export CC_FLAGS_FTRACE
841 KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
842 KBUILD_AFLAGS += $(CC_FLAGS_USING)
843 ifdef CONFIG_DYNAMIC_FTRACE
844 ifdef CONFIG_HAVE_C_RECORDMCOUNT
845 BUILD_C_RECORDMCOUNT := y
846 export BUILD_C_RECORDMCOUNT
851 # We trigger additional mismatches with less inlining
852 ifdef CONFIG_DEBUG_SECTION_MISMATCH
853 KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
856 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
857 KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
858 LDFLAGS_vmlinux += --gc-sections
861 ifdef CONFIG_LIVEPATCH
862 KBUILD_CFLAGS += $(call cc-option, -flive-patching=inline-clone)
865 # arch Makefile may override CC so keep this after arch Makefile is included
866 NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
868 # warn about C99 declaration after statement
869 KBUILD_CFLAGS += -Wdeclaration-after-statement
871 # Variable Length Arrays (VLAs) should not be used anywhere in the kernel
872 KBUILD_CFLAGS += -Wvla
874 # disable pointer signed / unsigned warnings in gcc 4.0
875 KBUILD_CFLAGS += -Wno-pointer-sign
877 # disable stringop warnings in gcc 8+
878 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
880 # We'll want to enable this eventually, but it's not going away for 5.7 at least
881 KBUILD_CFLAGS += $(call cc-disable-warning, zero-length-bounds)
882 KBUILD_CFLAGS += $(call cc-disable-warning, array-bounds)
884 # Enabled with W=2, disabled by default as noisy
885 KBUILD_CFLAGS += $(call cc-disable-warning, maybe-uninitialized)
887 # disable invalid "can't wrap" optimizations for signed / pointers
888 KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow)
890 # clang sets -fmerge-all-constants by default as optimization, but this
891 # is non-conforming behavior for C and in fact breaks the kernel, so we
892 # need to disable it here generally.
893 KBUILD_CFLAGS += $(call cc-option,-fno-merge-all-constants)
895 # for gcc -fno-merge-all-constants disables everything, but it is fine
896 # to have actual conforming behavior enabled.
897 KBUILD_CFLAGS += $(call cc-option,-fmerge-constants)
899 # Make sure -fstack-check isn't enabled (like gentoo apparently did)
900 KBUILD_CFLAGS += $(call cc-option,-fno-stack-check,)
902 # conserve stack if available
903 KBUILD_CFLAGS += $(call cc-option,-fconserve-stack)
905 # Prohibit date/time macros, which would make the build non-deterministic
906 KBUILD_CFLAGS += $(call cc-option,-Werror=date-time)
908 # enforce correct pointer usage
909 KBUILD_CFLAGS += $(call cc-option,-Werror=incompatible-pointer-types)
911 # Require designated initializers for all marked structures
912 KBUILD_CFLAGS += $(call cc-option,-Werror=designated-init)
914 # change __FILE__ to the relative path from the srctree
915 KBUILD_CFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
917 # ensure -fcf-protection is disabled when using retpoline as it is
918 # incompatible with -mindirect-branch=thunk-extern
919 ifdef CONFIG_RETPOLINE
920 KBUILD_CFLAGS += $(call cc-option,-fcf-protection=none)
923 include scripts/Makefile.kasan
924 include scripts/Makefile.extrawarn
925 include scripts/Makefile.ubsan
927 # Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
928 KBUILD_CPPFLAGS += $(KCPPFLAGS)
929 KBUILD_AFLAGS += $(KAFLAGS)
930 KBUILD_CFLAGS += $(KCFLAGS)
932 KBUILD_LDFLAGS_MODULE += --build-id
933 LDFLAGS_vmlinux += --build-id
935 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
936 LDFLAGS_vmlinux += $(call ld-option, -X,)
939 ifeq ($(CONFIG_RELR),y)
940 LDFLAGS_vmlinux += --pack-dyn-relocs=relr
943 # make the checker run with the right architecture
944 CHECKFLAGS += --arch=$(ARCH)
946 # insure the checker run with the right endianness
947 CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
949 # the checker needs the correct machine size
950 CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
952 # Default kernel image to build when no specific target is given.
953 # KBUILD_IMAGE may be overruled on the command line or
954 # set in the environment
955 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
957 export KBUILD_IMAGE ?= vmlinux
960 # INSTALL_PATH specifies where to place the updated kernel and system map
961 # images. Default is /boot, but you can set it to other values
962 export INSTALL_PATH ?= /boot
965 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
966 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
967 # an argument if needed. Otherwise it defaults to the kernel install path
969 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
972 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
973 # relocations required by build roots. This is not defined in the
974 # makefile but the argument can be passed to make if needed.
977 MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
981 # INSTALL_MOD_STRIP, if defined, will cause modules to be
982 # stripped after they are installed. If INSTALL_MOD_STRIP is '1', then
983 # the default option --strip-debug will be used. Otherwise,
984 # INSTALL_MOD_STRIP value will be used as the options to the strip command.
986 ifdef INSTALL_MOD_STRIP
987 ifeq ($(INSTALL_MOD_STRIP),1)
988 mod_strip_cmd = $(STRIP) --strip-debug
990 mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
991 endif # INSTALL_MOD_STRIP=1
994 endif # INSTALL_MOD_STRIP
997 # CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
998 # after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
999 # or CONFIG_MODULE_COMPRESS_XZ.
1001 mod_compress_cmd = true
1002 ifdef CONFIG_MODULE_COMPRESS
1003 ifdef CONFIG_MODULE_COMPRESS_GZIP
1004 mod_compress_cmd = gzip -n -f
1005 endif # CONFIG_MODULE_COMPRESS_GZIP
1006 ifdef CONFIG_MODULE_COMPRESS_XZ
1007 mod_compress_cmd = xz -f
1008 endif # CONFIG_MODULE_COMPRESS_XZ
1009 endif # CONFIG_MODULE_COMPRESS
1010 export mod_compress_cmd
1012 ifdef CONFIG_MODULE_SIG_ALL
1013 $(eval $(call config_filename,MODULE_SIG_KEY))
1015 mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
1021 HOST_LIBELF_LIBS = $(shell pkg-config libelf --libs 2>/dev/null || echo -lelf)
1023 ifdef CONFIG_STACK_VALIDATION
1024 has_libelf := $(call try-run,\
1025 echo "int main() {}" | $(HOSTCC) -xc -o /dev/null $(HOST_LIBELF_LIBS) -,1,0)
1026 ifeq ($(has_libelf),1)
1027 objtool_target := tools/objtool FORCE
1029 SKIP_STACK_VALIDATION := 1
1030 export SKIP_STACK_VALIDATION
1036 export MODORDER := $(extmod-prefix)modules.order
1037 export MODULES_NSDEPS := $(extmod-prefix)modules.nsdeps
1039 ifeq ($(KBUILD_EXTMOD),)
1040 core-y += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
1042 vmlinux-dirs := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
1043 $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
1044 $(net-y) $(net-m) $(libs-y) $(libs-m) $(virt-y)))
1046 vmlinux-alldirs := $(sort $(vmlinux-dirs) Documentation \
1047 $(patsubst %/,%,$(filter %/, $(init-) $(core-) \
1048 $(drivers-) $(net-) $(libs-) $(virt-))))
1050 build-dirs := $(vmlinux-dirs)
1051 clean-dirs := $(vmlinux-alldirs)
1053 init-y := $(patsubst %/, %/built-in.a, $(init-y))
1054 core-y := $(patsubst %/, %/built-in.a, $(core-y))
1055 drivers-y := $(patsubst %/, %/built-in.a, $(drivers-y))
1056 net-y := $(patsubst %/, %/built-in.a, $(net-y))
1057 libs-y2 := $(patsubst %/, %/built-in.a, $(filter %/, $(libs-y)))
1058 ifdef CONFIG_MODULES
1059 libs-y1 := $(filter-out %/, $(libs-y))
1060 libs-y2 += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1062 libs-y1 := $(patsubst %/, %/lib.a, $(libs-y))
1064 virt-y := $(patsubst %/, %/built-in.a, $(virt-y))
1066 # Externally visible symbols (used by link-vmlinux.sh)
1067 export KBUILD_VMLINUX_OBJS := $(head-y) $(init-y) $(core-y) $(libs-y2) \
1068 $(drivers-y) $(net-y) $(virt-y)
1069 export KBUILD_VMLINUX_LIBS := $(libs-y1)
1070 export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
1071 export LDFLAGS_vmlinux
1072 # used by scripts/Makefile.package
1073 export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) LICENSES arch include scripts tools)
1075 vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
1077 # Recurse until adjust_autoksyms.sh is satisfied
1078 PHONY += autoksyms_recursive
1079 ifdef CONFIG_TRIM_UNUSED_KSYMS
1080 autoksyms_recursive: descend modules.order
1081 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1082 "$(MAKE) -f $(srctree)/Makefile vmlinux"
1085 # For the kernel to actually contain only the needed exported symbols,
1086 # we have to build modules as well to determine what those symbols are.
1087 # (this can be evaluated only once include/config/auto.conf has been included)
1088 ifdef CONFIG_TRIM_UNUSED_KSYMS
1092 autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1094 quiet_cmd_autoksyms_h = GEN $@
1095 cmd_autoksyms_h = mkdir -p $(dir $@); \
1096 $(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@
1099 $(call cmd,autoksyms_h)
1101 ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1103 # Final link of vmlinux with optional arch pass after final link
1104 cmd_link-vmlinux = \
1105 $(CONFIG_SHELL) $< $(LD) $(KBUILD_LDFLAGS) $(LDFLAGS_vmlinux) ; \
1106 $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1108 vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1109 +$(call if_changed,link-vmlinux)
1113 # The actual objects are generated when descending,
1114 # make sure no implicit rule kicks in
1115 $(sort $(vmlinux-deps)): descend ;
1117 filechk_kernel.release = \
1118 echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1120 # Store (new) KERNELRELEASE string in include/config/kernel.release
1121 include/config/kernel.release: FORCE
1122 $(call filechk,kernel.release)
1124 # Additional helpers built in scripts/
1125 # Carefully list dependencies so we do not try to build scripts twice
1128 scripts: scripts_basic scripts_dtc
1129 $(Q)$(MAKE) $(build)=$(@)
1131 # Things we need to do before we recursively start building the kernel
1132 # or the modules are listed in "prepare".
1133 # A multi level approach is used. prepareN is processed before prepareN-1.
1134 # archprepare is used in arch Makefiles and when processed asm symlink,
1135 # version.h and scripts_basic is processed / created.
1137 PHONY += prepare archprepare
1139 archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1140 asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h
1142 prepare0: archprepare
1143 $(Q)$(MAKE) $(build)=scripts/mod
1144 $(Q)$(MAKE) $(build)=.
1146 # All the preparing..
1147 prepare: prepare0 prepare-objtool
1149 # Support for using generic headers in asm-generic
1150 asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1152 PHONY += asm-generic uapi-asm-generic
1153 asm-generic: uapi-asm-generic
1154 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1155 generic=include/asm-generic
1157 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1158 generic=include/uapi/asm-generic
1160 PHONY += prepare-objtool
1161 prepare-objtool: $(objtool_target)
1162 ifeq ($(SKIP_STACK_VALIDATION),1)
1163 ifdef CONFIG_UNWINDER_ORC
1164 @echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1167 @echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1171 # Generate some files
1172 # ---------------------------------------------------------------------------
1174 # KERNELRELEASE can change from a few different places, meaning version.h
1175 # needs to be updated, so this check is forced on all builds
1178 define filechk_utsrelease.h
1179 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1180 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1183 echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1186 define filechk_version.h
1187 echo \#define LINUX_VERSION_CODE $(shell \
1188 expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1189 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))'
1193 $(call filechk,version.h)
1194 $(Q)rm -f $(old_version_h)
1196 include/generated/utsrelease.h: include/config/kernel.release FORCE
1197 $(call filechk,utsrelease.h)
1201 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1202 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1204 # ---------------------------------------------------------------------------
1207 #Default location for installed headers
1208 export INSTALL_HDR_PATH = $(objtree)/usr
1210 quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1211 cmd_headers_install = \
1212 mkdir -p $(INSTALL_HDR_PATH); \
1213 rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1214 usr/include $(INSTALL_HDR_PATH)
1216 PHONY += headers_install
1217 headers_install: headers
1218 $(call cmd,headers_install)
1220 PHONY += archheaders archscripts
1222 hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1225 headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1226 $(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1227 $(error Headers not exportable for the $(SRCARCH) architecture))
1228 $(Q)$(MAKE) $(hdr-inst)=include/uapi
1229 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1231 # Deprecated. It is no-op now.
1232 PHONY += headers_check
1236 ifdef CONFIG_HEADERS_INSTALL
1240 PHONY += scripts_unifdef
1241 scripts_unifdef: scripts_basic
1242 $(Q)$(MAKE) $(build)=scripts scripts/unifdef
1244 # ---------------------------------------------------------------------------
1249 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1252 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1254 PHONY += kselftest-merge
1256 $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1257 $(Q)find $(srctree)/tools/testing/selftests -name config | \
1258 xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1259 $(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1261 # ---------------------------------------------------------------------------
1264 ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1265 dtstree := arch/$(SRCARCH)/boot/dts
1270 %.dtb: include/config/kernel.release scripts_dtc
1271 $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1273 PHONY += dtbs dtbs_install dtbs_check
1274 dtbs: include/config/kernel.release scripts_dtc
1275 $(Q)$(MAKE) $(build)=$(dtstree)
1277 ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1279 dtbs: dt_binding_check
1285 $(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1287 ifdef CONFIG_OF_EARLY_FLATTREE
1293 PHONY += scripts_dtc
1294 scripts_dtc: scripts_basic
1295 $(Q)$(MAKE) $(build)=scripts/dtc
1297 ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1298 export CHECK_DT_BINDING=y
1301 PHONY += dt_binding_check
1302 dt_binding_check: scripts_dtc
1303 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1305 # ---------------------------------------------------------------------------
1308 ifdef CONFIG_MODULES
1310 # By default, build modules as well
1316 # A module can be listed more than once in obj-m resulting in
1317 # duplicate lines in modules.order files. Those are removed
1318 # using awk while concatenating to the final file.
1321 modules: $(if $(KBUILD_BUILTIN),vmlinux) modules.order
1322 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1323 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh
1325 modules.order: descend
1326 $(Q)$(AWK) '!x[$$0]++' $(addsuffix /$@, $(build-dirs)) > $@
1328 # Target to prepare building external modules
1329 PHONY += modules_prepare
1330 modules_prepare: prepare
1332 # Target to install modules
1333 PHONY += modules_install
1334 modules_install: _modinst_ _modinst_post
1338 @rm -rf $(MODLIB)/kernel
1339 @rm -f $(MODLIB)/source
1340 @mkdir -p $(MODLIB)/kernel
1341 @ln -s $(abspath $(srctree)) $(MODLIB)/source
1342 @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
1343 rm -f $(MODLIB)/build ; \
1344 ln -s $(CURDIR) $(MODLIB)/build ; \
1346 @sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order
1347 @cp -f modules.builtin $(MODLIB)/
1348 @cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
1349 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1351 # This depmod is only for convenience to give the initial
1352 # boot a modules.dep even before / is mounted read-write. However the
1353 # boot script depmod is the master version.
1354 PHONY += _modinst_post
1355 _modinst_post: _modinst_
1358 ifeq ($(CONFIG_MODULE_SIG), y)
1359 PHONY += modules_sign
1361 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1364 else # CONFIG_MODULES
1366 # Modules not configured
1367 # ---------------------------------------------------------------------------
1369 PHONY += modules modules_install
1370 modules modules_install:
1372 @echo >&2 "The present kernel configuration has modules disabled."
1373 @echo >&2 "Type 'make config' and enable loadable module support."
1374 @echo >&2 "Then build a kernel with module support enabled."
1378 endif # CONFIG_MODULES
1381 # Cleaning is done on three levels.
1382 # make clean Delete most generated files
1383 # Leave enough to build external modules
1384 # make mrproper Delete the current configuration, and all generated files
1385 # make distclean Remove editor backup files, patch leftover files and the like
1387 # Directories & files removed with 'make clean'
1388 CLEAN_DIRS += include/ksym
1389 CLEAN_FILES += modules.builtin modules.builtin.modinfo modules.nsdeps
1391 # Directories & files removed with 'make mrproper'
1392 MRPROPER_DIRS += include/config include/generated \
1393 arch/$(SRCARCH)/include/generated .tmp_objdiff \
1394 debian/ snap/ tar-install/
1395 MRPROPER_FILES += .config .config.old .version \
1397 signing_key.pem signing_key.priv signing_key.x509 \
1398 x509.genkey extra_certificates signing_key.x509.keyid \
1399 signing_key.x509.signer vmlinux-gdb.py \
1402 # Directories & files removed with 'make distclean'
1404 DISTCLEAN_FILES += tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS
1406 # clean - Delete most, but leave enough to build external modules
1408 clean: rm-dirs := $(CLEAN_DIRS)
1409 clean: rm-files := $(CLEAN_FILES)
1411 PHONY += archclean vmlinuxclean
1414 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1415 $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1417 clean: archclean vmlinuxclean
1419 # mrproper - Delete all generated files, including .config
1421 mrproper: rm-dirs := $(wildcard $(MRPROPER_DIRS))
1422 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1423 mrproper-dirs := $(addprefix _mrproper_,scripts)
1425 PHONY += $(mrproper-dirs) mrproper
1427 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1429 mrproper: clean $(mrproper-dirs)
1435 distclean: rm-dirs := $(wildcard $(DISTCLEAN_DIRS))
1436 distclean: rm-files := $(wildcard $(DISTCLEAN_FILES))
1443 @find $(srctree) $(RCS_FIND_IGNORE) \
1444 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1445 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1446 -o -name 'core' \) \
1447 -type f -print | xargs rm -f
1450 # Packaging of the kernel to various formats
1451 # ---------------------------------------------------------------------------
1454 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1455 %pkg: include/config/kernel.release FORCE
1456 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1458 # Brief documentation of the typical targets used
1459 # ---------------------------------------------------------------------------
1461 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1462 boards := $(sort $(notdir $(boards)))
1463 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1464 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1468 @echo 'Cleaning targets:'
1469 @echo ' clean - Remove most generated files but keep the config and'
1470 @echo ' enough build support to build external modules'
1471 @echo ' mrproper - Remove all generated files + config + various backup files'
1472 @echo ' distclean - mrproper + remove editor backup and patch files'
1474 @echo 'Configuration targets:'
1475 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1477 @echo 'Other generic targets:'
1478 @echo ' all - Build all targets marked with [*]'
1479 @echo '* vmlinux - Build the bare kernel'
1480 @echo '* modules - Build all modules'
1481 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1482 @echo ' dir/ - Build all files in dir and below'
1483 @echo ' dir/file.[ois] - Build specified target only'
1484 @echo ' dir/file.ll - Build the LLVM assembly file'
1485 @echo ' (requires compiler support for LLVM assembly generation)'
1486 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1487 @echo ' (requires a recent binutils and recent build (System.map))'
1488 @echo ' dir/file.ko - Build module including final link'
1489 @echo ' modules_prepare - Set up for building external modules'
1490 @echo ' tags/TAGS - Generate tags file for editors'
1491 @echo ' cscope - Generate cscope index'
1492 @echo ' gtags - Generate GNU GLOBAL index'
1493 @echo ' kernelrelease - Output the release version string (use with make -s)'
1494 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1495 @echo ' image_name - Output the image name (use with make -s)'
1496 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1497 echo ' (default: $(INSTALL_HDR_PATH))'; \
1499 @echo 'Static analysers:'
1500 @echo ' checkstack - Generate a list of stack hogs'
1501 @echo ' namespacecheck - Name space analysis on compiled kernel'
1502 @echo ' versioncheck - Sanity check on version.h usage'
1503 @echo ' includecheck - Check for duplicate included header files'
1504 @echo ' export_report - List the usages of all exported symbols'
1505 @echo ' headerdep - Detect inclusion cycles in headers'
1506 @echo ' coccicheck - Check with Coccinelle'
1509 @echo ' nsdeps - Generate missing symbol namespace dependencies'
1511 @echo 'Kernel selftest:'
1512 @echo ' kselftest - Build and run kernel selftest'
1513 @echo ' Build, install, and boot kernel before'
1514 @echo ' running kselftest on it'
1515 @echo ' Run as root for full coverage'
1516 @echo ' kselftest-all - Build kernel selftest'
1517 @echo ' kselftest-install - Build and install kernel selftest'
1518 @echo ' kselftest-clean - Remove all generated kselftest files'
1519 @echo ' kselftest-merge - Merge all the config dependencies of'
1520 @echo ' kselftest to existing .config.'
1523 echo 'Devicetree:'; \
1524 echo '* dtbs - Build device tree blobs for enabled boards'; \
1525 echo ' dtbs_install - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1526 echo ' dt_binding_check - Validate device tree binding documents'; \
1527 echo ' dtbs_check - Validate device tree source files';\
1530 @echo 'Userspace tools targets:'
1531 @echo ' use "make tools/help"'
1532 @echo ' or "cd tools; make help"'
1534 @echo 'Kernel packaging:'
1535 @$(MAKE) -f $(srctree)/scripts/Makefile.package help
1537 @echo 'Documentation targets:'
1538 @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1540 @echo 'Architecture specific targets ($(SRCARCH)):'
1541 @$(if $(archhelp),$(archhelp),\
1542 echo ' No architecture specific help defined for $(SRCARCH)')
1545 $(foreach b, $(boards), \
1546 printf " %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1548 @$(if $(board-dirs), \
1549 $(foreach b, $(board-dirs), \
1550 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1551 printf " %-16s - Show all of the above\\n" help-boards; \
1554 @echo ' make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1555 @echo ' make V=2 [targets] 2 => give reason for rebuild of target'
1556 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1557 @echo ' make C=1 [targets] Check re-compiled c source with $$CHECK'
1558 @echo ' (sparse by default)'
1559 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1560 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1561 @echo ' make W=n [targets] Enable extra build checks, n=1,2,3 where'
1562 @echo ' 1: warnings which may be relevant and do not occur too often'
1563 @echo ' 2: warnings which occur quite often but may still be relevant'
1564 @echo ' 3: more obscure warnings, can most likely be ignored'
1565 @echo ' Multiple levels can be combined with W=12 or W=123'
1567 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1568 @echo 'For further info see the ./README file'
1571 help-board-dirs := $(addprefix help-,$(board-dirs))
1573 help-boards: $(help-board-dirs)
1575 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1577 $(help-board-dirs): help-%:
1578 @echo 'Architecture specific targets ($(SRCARCH) $*):'
1579 @$(if $(boards-per-dir), \
1580 $(foreach b, $(boards-per-dir), \
1581 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1585 # Documentation targets
1586 # ---------------------------------------------------------------------------
1587 DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1588 linkcheckdocs dochelp refcheckdocs
1589 PHONY += $(DOC_TARGETS)
1591 $(Q)$(MAKE) $(build)=Documentation $@
1594 # ---------------------------------------------------------------------------
1596 PHONY += scripts_gdb
1597 scripts_gdb: prepare0
1598 $(Q)$(MAKE) $(build)=scripts/gdb
1599 $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1601 ifdef CONFIG_GDB_SCRIPTS
1605 else # KBUILD_EXTMOD
1608 # External module support.
1609 # When building external modules the kernel used as basis is considered
1610 # read-only, and no consistency checks are made and the make
1611 # system is not used on the basis kernel. If updates are required
1612 # in the basis kernel ordinary make commands (without M=...) must
1615 # The following are the only valid targets when building external
1617 # make M=dir clean Delete all automatically generated files
1618 # make M=dir modules Make all modules in specified dir
1619 # make M=dir Same as 'make M=dir modules'
1620 # make M=dir modules_install
1621 # Install the modules built in the module directory
1622 # Assumes install directory is already created
1624 # We are always building modules
1627 PHONY += $(objtree)/Module.symvers
1628 $(objtree)/Module.symvers:
1629 @test -e $(objtree)/Module.symvers || ( \
1631 echo " WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1632 echo " is missing; modules will have no dependencies and modversions."; \
1635 build-dirs := $(KBUILD_EXTMOD)
1637 modules: descend $(objtree)/Module.symvers
1638 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1640 PHONY += modules_install
1641 modules_install: _emodinst_ _emodinst_post
1643 install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1646 $(Q)mkdir -p $(MODLIB)/$(install-dir)
1647 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1649 PHONY += _emodinst_post
1650 _emodinst_post: _emodinst_
1653 clean-dirs := $(KBUILD_EXTMOD)
1654 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps
1658 @echo >&2 '"$(MAKE) /" is no longer supported. Please use "$(MAKE) ./" instead.'
1662 @echo ' Building external modules.'
1663 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1665 @echo ' modules - default target, build the module(s)'
1666 @echo ' modules_install - install the module'
1667 @echo ' clean - remove generated files in module directory only'
1671 endif # KBUILD_EXTMOD
1674 # ---------------------------------------------------------------------------
1675 # To build individual files in subdirectories, you can do like this:
1677 # make foo/bar/baz.s
1679 # The supported suffixes for single-target are listed in 'single-targets'
1681 # To build only under specific subdirectories, you can do like this:
1687 # .ko is special because modpost is needed
1688 single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1689 single-no-ko := $(sort $(patsubst %.ko,%.mod, $(MAKECMDGOALS)))
1691 $(single-ko): single_modpost
1693 $(single-no-ko): descend
1696 ifeq ($(KBUILD_EXTMOD),)
1697 # For the single build of in-tree modules, use a temporary file to avoid
1698 # the situation of modules_install installing an invalid modules.order.
1699 MODORDER := .modules.tmp
1702 PHONY += single_modpost
1703 single_modpost: $(single-no-ko)
1704 $(Q){ $(foreach m, $(single-ko), echo $(extmod-prefix)$m;) } > $(MODORDER)
1705 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1709 export KBUILD_SINGLE_TARGETS := $(addprefix $(extmod-prefix), $(single-no-ko))
1711 # trim unrelated directories
1712 build-dirs := $(foreach d, $(build-dirs), \
1713 $(if $(filter $(d)/%, $(KBUILD_SINGLE_TARGETS)), $(d)))
1717 # Handle descending into subdirectories listed in $(build-dirs)
1718 # Preset locale variables to speed up the build process. Limit locale
1719 # tweaks to this spot to avoid wrong language settings when running
1720 # make menuconfig etc.
1721 # Error messages still appears in the original language
1722 PHONY += descend $(build-dirs)
1723 descend: $(build-dirs)
1724 $(build-dirs): prepare
1725 $(Q)$(MAKE) $(build)=$@ \
1726 single-build=$(if $(filter-out $@/, $(filter $@/%, $(single-no-ko))),1) \
1727 need-builtin=1 need-modorder=1
1729 clean-dirs := $(addprefix _clean_, $(clean-dirs))
1730 PHONY += $(clean-dirs) clean
1732 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1734 clean: $(clean-dirs)
1737 @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1738 \( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1740 -o -name '*.dtb' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1741 -o -name '*.dwo' -o -name '*.lst' \
1742 -o -name '*.su' -o -name '*.mod' \
1743 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1744 -o -name '*.lex.c' -o -name '*.tab.[ch]' \
1745 -o -name '*.asn1.[ch]' \
1746 -o -name '*.symtypes' -o -name 'modules.order' \
1747 -o -name '.tmp_*.o.*' \
1748 -o -name '*.c.[012]*.*' \
1750 -o -name '*.gcno' \) -type f -print | xargs rm -f
1752 # Generate tags for editors
1753 # ---------------------------------------------------------------------------
1754 quiet_cmd_tags = GEN $@
1755 cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1757 tags TAGS cscope gtags: FORCE
1760 # Script to generate missing namespace dependencies
1761 # ---------------------------------------------------------------------------
1764 nsdeps: export KBUILD_NSDEPS=1
1766 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1768 # Scripts to check various things for consistency
1769 # ---------------------------------------------------------------------------
1771 PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1774 find $(srctree)/* $(RCS_FIND_IGNORE) \
1775 -name '*.[hcS]' -type f -print | sort \
1776 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1779 find $(srctree)/* $(RCS_FIND_IGNORE) \
1780 -name '*.[hcS]' -type f -print | sort \
1781 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1784 $(Q)$(BASH) $(srctree)/scripts/$@
1787 $(PERL) $(srctree)/scripts/namespace.pl
1790 $(PERL) $(srctree)/scripts/export_report.pl
1792 PHONY += checkstack kernelrelease kernelversion image_name
1794 # UML needs a little special treatment here. It wants to use the host
1795 # toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
1796 # else wants $(ARCH), including people doing cross-builds, which means
1797 # that $(SUBARCH) doesn't work here.
1799 CHECKSTACK_ARCH := $(SUBARCH)
1801 CHECKSTACK_ARCH := $(ARCH)
1804 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1805 $(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1808 @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1811 @echo $(KERNELVERSION)
1814 @echo $(KBUILD_IMAGE)
1816 # Clear a bunch of variables before executing the submake
1818 ifeq ($(quiet),silent_)
1823 $(Q)mkdir -p $(objtree)/tools
1824 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1827 $(Q)mkdir -p $(objtree)/tools
1828 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1830 # FIXME Should go into a make.lib or something
1831 # ===========================================================================
1833 quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN $(wildcard $(rm-dirs)))
1834 cmd_rmdirs = rm -rf $(rm-dirs)
1836 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
1837 cmd_rmfiles = rm -f $(rm-files)
1839 # Run depmod only if we have System.map and depmod is executable
1840 quiet_cmd_depmod = DEPMOD $(KERNELRELEASE)
1841 cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1844 # read saved command lines for existing targets
1845 existing-targets := $(wildcard $(sort $(targets)))
1847 -include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
1849 endif # config-build
1851 endif # need-sub-make
1856 # Declare the contents of the PHONY variable as phony. We keep that
1857 # information in a variable so we can use it in if_changed and friends.