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
259 no-sync-config-targets := $(no-dot-config-targets) install %install \
261 single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
269 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
270 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
275 ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
276 ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
281 ifneq ($(KBUILD_EXTMOD),)
285 ifeq ($(KBUILD_EXTMOD),)
286 ifneq ($(filter config %config,$(MAKECMDGOALS)),)
288 ifneq ($(words $(MAKECMDGOALS)),1)
294 # We cannot build single targets and the others at the same time
295 ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
297 ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
302 # For "make -j clean all", "make -j mrproper defconfig all", etc.
303 ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
304 ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
309 # install and modules_install need also be processed one by one
310 ifneq ($(filter install,$(MAKECMDGOALS)),)
311 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
317 # ===========================================================================
318 # We're called with mixed targets (*config and build targets).
319 # Handle them one by one.
321 PHONY += $(MAKECMDGOALS) __build_one_by_one
323 $(filter-out __build_one_by_one, $(MAKECMDGOALS)): __build_one_by_one
328 for i in $(MAKECMDGOALS); do \
329 $(MAKE) -f $(srctree)/Makefile $$i; \
334 include scripts/Kbuild.include
336 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
337 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
338 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
339 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
341 include scripts/subarch.include
343 # Cross compiling and selecting different set of gcc/bin-utils
344 # ---------------------------------------------------------------------------
346 # When performing cross compilation for other architectures ARCH shall be set
347 # to the target architecture. (See arch/* for the possibilities).
348 # ARCH can be set during invocation of make:
350 # Another way is to have ARCH set in the environment.
351 # The default ARCH is the host where make is executed.
353 # CROSS_COMPILE specify the prefix used for all executables used
354 # during compilation. Only gcc and related bin-utils executables
355 # are prefixed with $(CROSS_COMPILE).
356 # CROSS_COMPILE can be set on the command line
357 # make CROSS_COMPILE=ia64-linux-
358 # Alternatively CROSS_COMPILE can be set in the environment.
359 # Default value for CROSS_COMPILE is not to prefix executables
360 # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
363 # Architecture as present in compile.h
364 UTS_MACHINE := $(ARCH)
367 # Additional ARCH settings for x86
371 ifeq ($(ARCH),x86_64)
375 # Additional ARCH settings for sparc
376 ifeq ($(ARCH),sparc32)
379 ifeq ($(ARCH),sparc64)
383 # Additional ARCH settings for sh
388 KCONFIG_CONFIG ?= .config
389 export KCONFIG_CONFIG
391 # SHELL used by kbuild
394 HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
395 HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
396 HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
400 KBUILD_HOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 \
401 -fomit-frame-pointer -std=gnu89 $(HOST_LFS_CFLAGS) \
403 KBUILD_HOSTCXXFLAGS := -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
404 KBUILD_HOSTLDFLAGS := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
405 KBUILD_HOSTLDLIBS := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
407 # Make variables (CC, etc...)
408 AS = $(CROSS_COMPILE)as
409 LD = $(CROSS_COMPILE)ld
410 CC = $(CROSS_COMPILE)gcc
412 AR = $(CROSS_COMPILE)ar
413 NM = $(CROSS_COMPILE)nm
414 STRIP = $(CROSS_COMPILE)strip
415 OBJCOPY = $(CROSS_COMPILE)objcopy
416 OBJDUMP = $(CROSS_COMPILE)objdump
417 OBJSIZE = $(CROSS_COMPILE)size
418 READELF = $(CROSS_COMPILE)readelf
423 INSTALLKERNEL := installkernel
424 DEPMOD = /sbin/depmod
431 CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
432 -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
441 # Use USERINCLUDE when you must reference the UAPI directories only.
443 -I$(srctree)/arch/$(SRCARCH)/include/uapi \
444 -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
445 -I$(srctree)/include/uapi \
446 -I$(objtree)/include/generated/uapi \
447 -include $(srctree)/include/linux/kconfig.h
449 # Use LINUXINCLUDE when you must reference the include/ directory.
450 # Needed to be compatible with the O= option
452 -I$(srctree)/arch/$(SRCARCH)/include \
453 -I$(objtree)/arch/$(SRCARCH)/include/generated \
454 $(if $(building_out_of_srctree),-I$(srctree)/include) \
455 -I$(objtree)/include \
458 KBUILD_AFLAGS := -D__ASSEMBLY__ -fno-PIE
459 KBUILD_CFLAGS := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
460 -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
461 -Werror=implicit-function-declaration -Werror=implicit-int \
462 -Wno-format-security \
464 KBUILD_CPPFLAGS := -D__KERNEL__
465 KBUILD_AFLAGS_KERNEL :=
466 KBUILD_CFLAGS_KERNEL :=
467 KBUILD_AFLAGS_MODULE := -DMODULE
468 KBUILD_CFLAGS_MODULE := -DMODULE
469 KBUILD_LDFLAGS_MODULE :=
470 export KBUILD_LDS_MODULE := $(srctree)/scripts/module-common.lds
472 GCC_PLUGINS_CFLAGS :=
475 export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE AS LD CC
476 export CPP AR NM STRIP OBJCOPY OBJDUMP OBJSIZE READELF PAHOLE LEX YACC AWK INSTALLKERNEL
477 export PERL PYTHON PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
478 export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
480 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
481 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
482 export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN
483 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
484 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
485 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
487 # Files to ignore in find ... statements
489 export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o \
490 -name CVS -o -name .pc -o -name .hg -o -name .git \) \
492 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
493 --exclude CVS --exclude .pc --exclude .hg --exclude .git
495 # ===========================================================================
496 # Rules shared between *config targets and build targets
498 # Basic helpers built in scripts/basic/
499 PHONY += scripts_basic
501 $(Q)$(MAKE) $(build)=scripts/basic
502 $(Q)rm -f .tmp_quiet_recordmcount
504 PHONY += outputmakefile
505 # Before starting out-of-tree build, make sure the source tree is clean.
506 # outputmakefile generates a Makefile in the output directory, if using a
507 # separate output directory. This allows convenient use of make in the
509 # At the same time when output Makefile generated, generate .gitignore to
510 # ignore whole output directory
512 ifdef building_out_of_srctree
513 $(Q)if [ -f $(srctree)/.config -o \
514 -d $(srctree)/include/config -o \
515 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
517 echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
518 echo >&2 "*** in $(abs_srctree)";\
522 $(Q)ln -fsn $(srctree) source
523 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile $(srctree)
524 $(Q)test -e .gitignore || \
525 { echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
528 ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),)
529 ifneq ($(CROSS_COMPILE),)
530 CLANG_FLAGS += --target=$(notdir $(CROSS_COMPILE:%-=%))
531 GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
532 CLANG_FLAGS += --prefix=$(GCC_TOOLCHAIN_DIR)
533 GCC_TOOLCHAIN := $(realpath $(GCC_TOOLCHAIN_DIR)/..)
535 ifneq ($(GCC_TOOLCHAIN),)
536 CLANG_FLAGS += --gcc-toolchain=$(GCC_TOOLCHAIN)
538 ifeq ($(shell $(AS) --version 2>&1 | head -n 1 | grep clang),)
539 CLANG_FLAGS += -no-integrated-as
541 CLANG_FLAGS += -Werror=unknown-warning-option
542 KBUILD_CFLAGS += $(CLANG_FLAGS)
543 KBUILD_AFLAGS += $(CLANG_FLAGS)
547 # The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
548 # Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
549 # CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
550 # and from include/config/auto.conf.cmd to detect the compiler upgrade.
551 CC_VERSION_TEXT = $(shell $(CC) --version 2>/dev/null | head -n 1)
554 # ===========================================================================
555 # *config targets only - make sure prerequisites are updated, and descend
556 # in scripts/kconfig to make the *config target
558 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
559 # KBUILD_DEFCONFIG may point out an alternative default configuration
560 # used for 'make defconfig'
561 include arch/$(SRCARCH)/Makefile
562 export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
564 config: outputmakefile scripts_basic FORCE
565 $(Q)$(MAKE) $(build)=scripts/kconfig $@
567 %config: outputmakefile scripts_basic FORCE
568 $(Q)$(MAKE) $(build)=scripts/kconfig $@
571 # ===========================================================================
572 # Build targets only - this includes vmlinux, arch specific targets, clean
573 # targets and others. In general all targets except *config targets.
575 # If building an external module we do not care about the all: rule
576 # but instead _all depend on modules
578 ifeq ($(KBUILD_EXTMOD),)
584 # Decide whether to build built-in, modular, or both.
585 # Normally, just do built-in.
590 # If we have only "make modules", don't compile built-in objects.
591 # When we're building modules with modversions, we need to consider
592 # the built-in objects during the descend as well, in order to
593 # make sure the checksums are up to date before we record them.
595 ifeq ($(MAKECMDGOALS),modules)
596 KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
599 # If we have "make <whatever> modules", compile modules
600 # in addition to whatever we do anyway.
601 # Just "make" or "make all" shall build modules as well
603 ifneq ($(filter all _all modules nsdeps,$(MAKECMDGOALS)),)
607 ifeq ($(MAKECMDGOALS),)
611 export KBUILD_MODULES KBUILD_BUILTIN
614 include include/config/auto.conf
617 ifeq ($(KBUILD_EXTMOD),)
618 # Objects we will link into vmlinux / subdirs we need to visit
620 drivers-y := drivers/ sound/
621 drivers-$(CONFIG_SAMPLES) += samples/
626 endif # KBUILD_EXTMOD
628 # The all: target is the default when no target is given on the
630 # This allow a user to issue only 'make' to build a kernel including modules
631 # Defaults to vmlinux, but the arch makefile usually adds further targets
634 CFLAGS_GCOV := -fprofile-arcs -ftest-coverage \
635 $(call cc-option,-fno-tree-loop-im) \
636 $(call cc-disable-warning,maybe-uninitialized,)
639 # The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
640 ifdef CONFIG_FUNCTION_TRACER
641 CC_FLAGS_FTRACE := -pg
644 RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
645 RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
646 RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
647 RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
648 RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
649 RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
650 export RETPOLINE_CFLAGS
651 export RETPOLINE_VDSO_CFLAGS
653 include arch/$(SRCARCH)/Makefile
656 ifdef may-sync-config
657 # Read in dependencies to all Kconfig* files, make sure to run syncconfig if
658 # changes are detected. This should be included after arch/$(SRCARCH)/Makefile
659 # because some architectures define CROSS_COMPILE there.
660 include include/config/auto.conf.cmd
664 @echo >&2 '*** Configuration file "$@" not found!'
666 @echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
667 @echo >&2 '*** "make menuconfig" or "make xconfig").'
671 # The actual configuration files used during the build are stored in
672 # include/generated/ and include/config/. Update them if .config is newer than
673 # include/config/auto.conf (which mirrors .config).
675 # This exploits the 'multi-target pattern rule' trick.
676 # The syncconfig should be executed only once to make all the targets.
677 %/auto.conf %/auto.conf.cmd: $(KCONFIG_CONFIG)
678 $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
679 else # !may-sync-config
680 # External modules and some install targets need include/generated/autoconf.h
681 # and include/config/auto.conf but do not care if they are up-to-date.
682 # Use auto.conf to trigger the test
683 PHONY += include/config/auto.conf
685 include/config/auto.conf:
686 $(Q)test -e include/generated/autoconf.h -a -e $@ || ( \
688 echo >&2 " ERROR: Kernel configuration is invalid."; \
689 echo >&2 " include/generated/autoconf.h or $@ are missing.";\
690 echo >&2 " Run 'make oldconfig && make prepare' on kernel src to fix it."; \
694 endif # may-sync-config
697 KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,)
698 KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,)
699 KBUILD_CFLAGS += $(call cc-disable-warning, format-truncation)
700 KBUILD_CFLAGS += $(call cc-disable-warning, format-overflow)
701 KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
703 ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
705 else ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3
707 else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
711 ifdef CONFIG_CC_DISABLE_WARN_MAYBE_UNINITIALIZED
712 KBUILD_CFLAGS += -Wno-maybe-uninitialized
715 # Tell gcc to never replace conditional load with a non-conditional one
716 KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
718 include scripts/Makefile.kcov
719 include scripts/Makefile.gcc-plugins
721 ifdef CONFIG_READABLE_ASM
722 # Disable optimizations that make assembler listings hard to read.
723 # reorder blocks reorders the control in the function
724 # ipa clone creates specialized cloned functions
725 # partial inlining inlines only parts of functions
726 KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
727 $(call cc-option,-fno-ipa-cp-clone,) \
728 $(call cc-option,-fno-partial-inlining)
731 ifneq ($(CONFIG_FRAME_WARN),0)
732 KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
735 stackp-flags-$(CONFIG_CC_HAS_STACKPROTECTOR_NONE) := -fno-stack-protector
736 stackp-flags-$(CONFIG_STACKPROTECTOR) := -fstack-protector
737 stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG) := -fstack-protector-strong
739 KBUILD_CFLAGS += $(stackp-flags-y)
741 ifdef CONFIG_CC_IS_CLANG
742 KBUILD_CPPFLAGS += -Qunused-arguments
743 KBUILD_CFLAGS += -Wno-format-invalid-specifier
744 KBUILD_CFLAGS += -Wno-gnu
745 # Quiet clang warning: comparison of unsigned expression < 0 is always false
746 KBUILD_CFLAGS += -Wno-tautological-compare
747 # CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
748 # source of a reference will be _MergedGlobals and not on of the whitelisted names.
749 # See modpost pattern 2
750 KBUILD_CFLAGS += -mno-global-merge
753 # These warnings generated too much noise in a regular build.
754 # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
755 KBUILD_CFLAGS += -Wno-unused-but-set-variable
757 # Warn about unmarked fall-throughs in switch statement.
758 # Disabled for clang while comment to attribute conversion happens and
759 # https://github.com/ClangBuiltLinux/linux/issues/636 is discussed.
760 KBUILD_CFLAGS += $(call cc-option,-Wimplicit-fallthrough,)
763 KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
764 ifdef CONFIG_FRAME_POINTER
765 KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
767 # Some targets (ARM with Thumb2, for example), can't be built with frame
768 # pointers. For those, we don't have FUNCTION_TRACER automatically
769 # select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
770 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
771 # -fomit-frame-pointer with FUNCTION_TRACER.
772 ifndef CONFIG_FUNCTION_TRACER
773 KBUILD_CFLAGS += -fomit-frame-pointer
777 # Initialize all stack variables with a pattern, if desired.
778 ifdef CONFIG_INIT_STACK_ALL
779 KBUILD_CFLAGS += -ftrivial-auto-var-init=pattern
782 DEBUG_CFLAGS := $(call cc-option, -fno-var-tracking-assignments)
784 ifdef CONFIG_DEBUG_INFO
785 ifdef CONFIG_DEBUG_INFO_SPLIT
786 DEBUG_CFLAGS += -gsplit-dwarf
790 KBUILD_AFLAGS += -Wa,-gdwarf-2
792 ifdef CONFIG_DEBUG_INFO_DWARF4
793 DEBUG_CFLAGS += -gdwarf-4
796 ifdef CONFIG_DEBUG_INFO_REDUCED
797 DEBUG_CFLAGS += $(call cc-option, -femit-struct-debug-baseonly) \
798 $(call cc-option,-fno-var-tracking)
801 KBUILD_CFLAGS += $(DEBUG_CFLAGS)
804 ifdef CONFIG_FUNCTION_TRACER
805 ifdef CONFIG_FTRACE_MCOUNT_RECORD
806 # gcc 5 supports generating the mcount tables directly
807 ifeq ($(call cc-option-yn,-mrecord-mcount),y)
808 CC_FLAGS_FTRACE += -mrecord-mcount
809 export CC_USING_RECORD_MCOUNT := 1
811 ifdef CONFIG_HAVE_NOP_MCOUNT
812 ifeq ($(call cc-option-yn, -mnop-mcount),y)
813 CC_FLAGS_FTRACE += -mnop-mcount
814 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
818 ifdef CONFIG_HAVE_FENTRY
819 ifeq ($(call cc-option-yn, -mfentry),y)
820 CC_FLAGS_FTRACE += -mfentry
821 CC_FLAGS_USING += -DCC_USING_FENTRY
824 export CC_FLAGS_FTRACE
825 KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
826 KBUILD_AFLAGS += $(CC_FLAGS_USING)
827 ifdef CONFIG_DYNAMIC_FTRACE
828 ifdef CONFIG_HAVE_C_RECORDMCOUNT
829 BUILD_C_RECORDMCOUNT := y
830 export BUILD_C_RECORDMCOUNT
835 # We trigger additional mismatches with less inlining
836 ifdef CONFIG_DEBUG_SECTION_MISMATCH
837 KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
840 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
841 KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
842 LDFLAGS_vmlinux += --gc-sections
845 ifdef CONFIG_LIVEPATCH
846 KBUILD_CFLAGS += $(call cc-option, -flive-patching=inline-clone)
849 # arch Makefile may override CC so keep this after arch Makefile is included
850 NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
852 # warn about C99 declaration after statement
853 KBUILD_CFLAGS += -Wdeclaration-after-statement
855 # Variable Length Arrays (VLAs) should not be used anywhere in the kernel
856 KBUILD_CFLAGS += -Wvla
858 # disable pointer signed / unsigned warnings in gcc 4.0
859 KBUILD_CFLAGS += -Wno-pointer-sign
861 # disable stringop warnings in gcc 8+
862 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
864 # disable invalid "can't wrap" optimizations for signed / pointers
865 KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow)
867 # clang sets -fmerge-all-constants by default as optimization, but this
868 # is non-conforming behavior for C and in fact breaks the kernel, so we
869 # need to disable it here generally.
870 KBUILD_CFLAGS += $(call cc-option,-fno-merge-all-constants)
872 # for gcc -fno-merge-all-constants disables everything, but it is fine
873 # to have actual conforming behavior enabled.
874 KBUILD_CFLAGS += $(call cc-option,-fmerge-constants)
876 # Make sure -fstack-check isn't enabled (like gentoo apparently did)
877 KBUILD_CFLAGS += $(call cc-option,-fno-stack-check,)
879 # conserve stack if available
880 KBUILD_CFLAGS += $(call cc-option,-fconserve-stack)
882 # Prohibit date/time macros, which would make the build non-deterministic
883 KBUILD_CFLAGS += $(call cc-option,-Werror=date-time)
885 # enforce correct pointer usage
886 KBUILD_CFLAGS += $(call cc-option,-Werror=incompatible-pointer-types)
888 # Require designated initializers for all marked structures
889 KBUILD_CFLAGS += $(call cc-option,-Werror=designated-init)
891 # change __FILE__ to the relative path from the srctree
892 KBUILD_CFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
894 # ensure -fcf-protection is disabled when using retpoline as it is
895 # incompatible with -mindirect-branch=thunk-extern
896 ifdef CONFIG_RETPOLINE
897 KBUILD_CFLAGS += $(call cc-option,-fcf-protection=none)
900 include scripts/Makefile.kasan
901 include scripts/Makefile.extrawarn
902 include scripts/Makefile.ubsan
904 # Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
905 KBUILD_CPPFLAGS += $(KCPPFLAGS)
906 KBUILD_AFLAGS += $(KAFLAGS)
907 KBUILD_CFLAGS += $(KCFLAGS)
909 KBUILD_LDFLAGS_MODULE += --build-id
910 LDFLAGS_vmlinux += --build-id
912 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
913 LDFLAGS_vmlinux += $(call ld-option, -X,)
916 ifeq ($(CONFIG_RELR),y)
917 LDFLAGS_vmlinux += --pack-dyn-relocs=relr
920 # make the checker run with the right architecture
921 CHECKFLAGS += --arch=$(ARCH)
923 # insure the checker run with the right endianness
924 CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
926 # the checker needs the correct machine size
927 CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
929 # Default kernel image to build when no specific target is given.
930 # KBUILD_IMAGE may be overruled on the command line or
931 # set in the environment
932 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
934 export KBUILD_IMAGE ?= vmlinux
937 # INSTALL_PATH specifies where to place the updated kernel and system map
938 # images. Default is /boot, but you can set it to other values
939 export INSTALL_PATH ?= /boot
942 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
943 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
944 # an argument if needed. Otherwise it defaults to the kernel install path
946 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
949 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
950 # relocations required by build roots. This is not defined in the
951 # makefile but the argument can be passed to make if needed.
954 MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
958 # INSTALL_MOD_STRIP, if defined, will cause modules to be
959 # stripped after they are installed. If INSTALL_MOD_STRIP is '1', then
960 # the default option --strip-debug will be used. Otherwise,
961 # INSTALL_MOD_STRIP value will be used as the options to the strip command.
963 ifdef INSTALL_MOD_STRIP
964 ifeq ($(INSTALL_MOD_STRIP),1)
965 mod_strip_cmd = $(STRIP) --strip-debug
967 mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
968 endif # INSTALL_MOD_STRIP=1
971 endif # INSTALL_MOD_STRIP
974 # CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
975 # after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
976 # or CONFIG_MODULE_COMPRESS_XZ.
978 mod_compress_cmd = true
979 ifdef CONFIG_MODULE_COMPRESS
980 ifdef CONFIG_MODULE_COMPRESS_GZIP
981 mod_compress_cmd = gzip -n -f
982 endif # CONFIG_MODULE_COMPRESS_GZIP
983 ifdef CONFIG_MODULE_COMPRESS_XZ
984 mod_compress_cmd = xz -f
985 endif # CONFIG_MODULE_COMPRESS_XZ
986 endif # CONFIG_MODULE_COMPRESS
987 export mod_compress_cmd
989 ifdef CONFIG_MODULE_SIG_ALL
990 $(eval $(call config_filename,MODULE_SIG_KEY))
992 mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
998 HOST_LIBELF_LIBS = $(shell pkg-config libelf --libs 2>/dev/null || echo -lelf)
1000 ifdef CONFIG_STACK_VALIDATION
1001 has_libelf := $(call try-run,\
1002 echo "int main() {}" | $(HOSTCC) -xc -o /dev/null $(HOST_LIBELF_LIBS) -,1,0)
1003 ifeq ($(has_libelf),1)
1004 objtool_target := tools/objtool FORCE
1006 SKIP_STACK_VALIDATION := 1
1007 export SKIP_STACK_VALIDATION
1013 export MODORDER := $(extmod-prefix)modules.order
1014 export MODULES_NSDEPS := $(extmod-prefix)modules.nsdeps
1016 ifeq ($(KBUILD_EXTMOD),)
1017 core-y += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
1019 vmlinux-dirs := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
1020 $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
1021 $(net-y) $(net-m) $(libs-y) $(libs-m) $(virt-y)))
1023 vmlinux-alldirs := $(sort $(vmlinux-dirs) Documentation \
1024 $(patsubst %/,%,$(filter %/, $(init-) $(core-) \
1025 $(drivers-) $(net-) $(libs-) $(virt-))))
1027 build-dirs := $(vmlinux-dirs)
1028 clean-dirs := $(vmlinux-alldirs)
1030 init-y := $(patsubst %/, %/built-in.a, $(init-y))
1031 core-y := $(patsubst %/, %/built-in.a, $(core-y))
1032 drivers-y := $(patsubst %/, %/built-in.a, $(drivers-y))
1033 net-y := $(patsubst %/, %/built-in.a, $(net-y))
1034 libs-y1 := $(patsubst %/, %/lib.a, $(libs-y))
1035 libs-y2 := $(patsubst %/, %/built-in.a, $(filter-out %.a, $(libs-y)))
1036 virt-y := $(patsubst %/, %/built-in.a, $(virt-y))
1038 # Externally visible symbols (used by link-vmlinux.sh)
1039 export KBUILD_VMLINUX_OBJS := $(head-y) $(init-y) $(core-y) $(libs-y2) \
1040 $(drivers-y) $(net-y) $(virt-y)
1041 export KBUILD_VMLINUX_LIBS := $(libs-y1)
1042 export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
1043 export LDFLAGS_vmlinux
1044 # used by scripts/Makefile.package
1045 export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) LICENSES arch include scripts tools)
1047 vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
1049 # Recurse until adjust_autoksyms.sh is satisfied
1050 PHONY += autoksyms_recursive
1051 ifdef CONFIG_TRIM_UNUSED_KSYMS
1052 autoksyms_recursive: descend modules.order
1053 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1054 "$(MAKE) -f $(srctree)/Makefile vmlinux"
1057 # For the kernel to actually contain only the needed exported symbols,
1058 # we have to build modules as well to determine what those symbols are.
1059 # (this can be evaluated only once include/config/auto.conf has been included)
1060 ifdef CONFIG_TRIM_UNUSED_KSYMS
1064 autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1067 $(Q)mkdir -p $(dir $@)
1070 ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1072 # Final link of vmlinux with optional arch pass after final link
1073 cmd_link-vmlinux = \
1074 $(CONFIG_SHELL) $< $(LD) $(KBUILD_LDFLAGS) $(LDFLAGS_vmlinux) ; \
1075 $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1077 vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1078 +$(call if_changed,link-vmlinux)
1082 # The actual objects are generated when descending,
1083 # make sure no implicit rule kicks in
1084 $(sort $(vmlinux-deps)): descend ;
1086 filechk_kernel.release = \
1087 echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1089 # Store (new) KERNELRELEASE string in include/config/kernel.release
1090 include/config/kernel.release: FORCE
1091 $(call filechk,kernel.release)
1093 # Additional helpers built in scripts/
1094 # Carefully list dependencies so we do not try to build scripts twice
1097 scripts: scripts_basic scripts_dtc
1098 $(Q)$(MAKE) $(build)=$(@)
1100 # Things we need to do before we recursively start building the kernel
1101 # or the modules are listed in "prepare".
1102 # A multi level approach is used. prepareN is processed before prepareN-1.
1103 # archprepare is used in arch Makefiles and when processed asm symlink,
1104 # version.h and scripts_basic is processed / created.
1106 PHONY += prepare archprepare
1108 archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1109 asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h
1111 prepare0: archprepare
1112 $(Q)$(MAKE) $(build)=scripts/mod
1113 $(Q)$(MAKE) $(build)=.
1115 # All the preparing..
1116 prepare: prepare0 prepare-objtool
1118 # Support for using generic headers in asm-generic
1119 asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1121 PHONY += asm-generic uapi-asm-generic
1122 asm-generic: uapi-asm-generic
1123 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1124 generic=include/asm-generic
1126 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1127 generic=include/uapi/asm-generic
1129 PHONY += prepare-objtool
1130 prepare-objtool: $(objtool_target)
1131 ifeq ($(SKIP_STACK_VALIDATION),1)
1132 ifdef CONFIG_UNWINDER_ORC
1133 @echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1136 @echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1140 # Generate some files
1141 # ---------------------------------------------------------------------------
1143 # KERNELRELEASE can change from a few different places, meaning version.h
1144 # needs to be updated, so this check is forced on all builds
1147 define filechk_utsrelease.h
1148 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1149 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1152 echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1155 define filechk_version.h
1156 echo \#define LINUX_VERSION_CODE $(shell \
1157 expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1158 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))'
1162 $(call filechk,version.h)
1163 $(Q)rm -f $(old_version_h)
1165 include/generated/utsrelease.h: include/config/kernel.release FORCE
1166 $(call filechk,utsrelease.h)
1170 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1171 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1173 # ---------------------------------------------------------------------------
1176 #Default location for installed headers
1177 export INSTALL_HDR_PATH = $(objtree)/usr
1179 quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1180 cmd_headers_install = \
1181 mkdir -p $(INSTALL_HDR_PATH); \
1182 rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1183 usr/include $(INSTALL_HDR_PATH)
1185 PHONY += headers_install
1186 headers_install: headers
1187 $(call cmd,headers_install)
1189 PHONY += archheaders archscripts
1191 hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1194 headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1195 $(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1196 $(error Headers not exportable for the $(SRCARCH) architecture))
1197 $(Q)$(MAKE) $(hdr-inst)=include/uapi
1198 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1200 # Deprecated. It is no-op now.
1201 PHONY += headers_check
1205 ifdef CONFIG_HEADERS_INSTALL
1209 PHONY += scripts_unifdef
1210 scripts_unifdef: scripts_basic
1211 $(Q)$(MAKE) $(build)=scripts scripts/unifdef
1213 # ---------------------------------------------------------------------------
1218 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1221 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1223 PHONY += kselftest-merge
1225 $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1226 $(Q)find $(srctree)/tools/testing/selftests -name config | \
1227 xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1228 $(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1230 # ---------------------------------------------------------------------------
1233 ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1234 dtstree := arch/$(SRCARCH)/boot/dts
1239 %.dtb: include/config/kernel.release scripts_dtc
1240 $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1242 PHONY += dtbs dtbs_install dtbs_check
1243 dtbs dtbs_check: include/config/kernel.release scripts_dtc
1244 $(Q)$(MAKE) $(build)=$(dtstree)
1246 dtbs_check: export CHECK_DTBS=1
1247 dtbs_check: dt_binding_check
1250 $(Q)$(MAKE) $(dtbinst)=$(dtstree)
1252 ifdef CONFIG_OF_EARLY_FLATTREE
1258 PHONY += scripts_dtc
1259 scripts_dtc: scripts_basic
1260 $(Q)$(MAKE) $(build)=scripts/dtc
1262 PHONY += dt_binding_check
1263 dt_binding_check: scripts_dtc
1264 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1266 # ---------------------------------------------------------------------------
1269 ifdef CONFIG_MODULES
1271 # By default, build modules as well
1277 # A module can be listed more than once in obj-m resulting in
1278 # duplicate lines in modules.order files. Those are removed
1279 # using awk while concatenating to the final file.
1282 modules: $(if $(KBUILD_BUILTIN),vmlinux) modules.order
1283 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1284 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh
1286 modules.order: descend
1287 $(Q)$(AWK) '!x[$$0]++' $(addsuffix /$@, $(build-dirs)) > $@
1289 # Target to prepare building external modules
1290 PHONY += modules_prepare
1291 modules_prepare: prepare
1293 # Target to install modules
1294 PHONY += modules_install
1295 modules_install: _modinst_ _modinst_post
1299 @rm -rf $(MODLIB)/kernel
1300 @rm -f $(MODLIB)/source
1301 @mkdir -p $(MODLIB)/kernel
1302 @ln -s $(abspath $(srctree)) $(MODLIB)/source
1303 @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
1304 rm -f $(MODLIB)/build ; \
1305 ln -s $(CURDIR) $(MODLIB)/build ; \
1307 @sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order
1308 @cp -f modules.builtin $(MODLIB)/
1309 @cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
1310 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1312 # This depmod is only for convenience to give the initial
1313 # boot a modules.dep even before / is mounted read-write. However the
1314 # boot script depmod is the master version.
1315 PHONY += _modinst_post
1316 _modinst_post: _modinst_
1319 ifeq ($(CONFIG_MODULE_SIG), y)
1320 PHONY += modules_sign
1322 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1325 else # CONFIG_MODULES
1327 # Modules not configured
1328 # ---------------------------------------------------------------------------
1330 PHONY += modules modules_install
1331 modules modules_install:
1333 @echo >&2 "The present kernel configuration has modules disabled."
1334 @echo >&2 "Type 'make config' and enable loadable module support."
1335 @echo >&2 "Then build a kernel with module support enabled."
1339 endif # CONFIG_MODULES
1342 # Cleaning is done on three levels.
1343 # make clean Delete most generated files
1344 # Leave enough to build external modules
1345 # make mrproper Delete the current configuration, and all generated files
1346 # make distclean Remove editor backup files, patch leftover files and the like
1348 # Directories & files removed with 'make clean'
1349 CLEAN_DIRS += include/ksym
1350 CLEAN_FILES += modules.builtin modules.builtin.modinfo modules.nsdeps
1352 # Directories & files removed with 'make mrproper'
1353 MRPROPER_DIRS += include/config include/generated \
1354 arch/$(SRCARCH)/include/generated .tmp_objdiff \
1355 debian/ snap/ tar-install/
1356 MRPROPER_FILES += .config .config.old .version \
1358 signing_key.pem signing_key.priv signing_key.x509 \
1359 x509.genkey extra_certificates signing_key.x509.keyid \
1360 signing_key.x509.signer vmlinux-gdb.py \
1363 # Directories & files removed with 'make distclean'
1365 DISTCLEAN_FILES += tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS
1367 # clean - Delete most, but leave enough to build external modules
1369 clean: rm-dirs := $(CLEAN_DIRS)
1370 clean: rm-files := $(CLEAN_FILES)
1372 PHONY += archclean vmlinuxclean
1375 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1376 $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1378 clean: archclean vmlinuxclean
1380 # mrproper - Delete all generated files, including .config
1382 mrproper: rm-dirs := $(wildcard $(MRPROPER_DIRS))
1383 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1384 mrproper-dirs := $(addprefix _mrproper_,scripts)
1386 PHONY += $(mrproper-dirs) mrproper
1388 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1390 mrproper: clean $(mrproper-dirs)
1396 distclean: rm-dirs := $(wildcard $(DISTCLEAN_DIRS))
1397 distclean: rm-files := $(wildcard $(DISTCLEAN_FILES))
1404 @find $(srctree) $(RCS_FIND_IGNORE) \
1405 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1406 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1407 -o -name 'core' \) \
1408 -type f -print | xargs rm -f
1411 # Packaging of the kernel to various formats
1412 # ---------------------------------------------------------------------------
1415 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1416 %pkg: include/config/kernel.release FORCE
1417 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1419 # Brief documentation of the typical targets used
1420 # ---------------------------------------------------------------------------
1422 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1423 boards := $(sort $(notdir $(boards)))
1424 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1425 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1429 @echo 'Cleaning targets:'
1430 @echo ' clean - Remove most generated files but keep the config and'
1431 @echo ' enough build support to build external modules'
1432 @echo ' mrproper - Remove all generated files + config + various backup files'
1433 @echo ' distclean - mrproper + remove editor backup and patch files'
1435 @echo 'Configuration targets:'
1436 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1438 @echo 'Other generic targets:'
1439 @echo ' all - Build all targets marked with [*]'
1440 @echo '* vmlinux - Build the bare kernel'
1441 @echo '* modules - Build all modules'
1442 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1443 @echo ' dir/ - Build all files in dir and below'
1444 @echo ' dir/file.[ois] - Build specified target only'
1445 @echo ' dir/file.ll - Build the LLVM assembly file'
1446 @echo ' (requires compiler support for LLVM assembly generation)'
1447 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1448 @echo ' (requires a recent binutils and recent build (System.map))'
1449 @echo ' dir/file.ko - Build module including final link'
1450 @echo ' modules_prepare - Set up for building external modules'
1451 @echo ' tags/TAGS - Generate tags file for editors'
1452 @echo ' cscope - Generate cscope index'
1453 @echo ' gtags - Generate GNU GLOBAL index'
1454 @echo ' kernelrelease - Output the release version string (use with make -s)'
1455 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1456 @echo ' image_name - Output the image name (use with make -s)'
1457 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1458 echo ' (default: $(INSTALL_HDR_PATH))'; \
1460 @echo 'Static analysers:'
1461 @echo ' checkstack - Generate a list of stack hogs'
1462 @echo ' namespacecheck - Name space analysis on compiled kernel'
1463 @echo ' versioncheck - Sanity check on version.h usage'
1464 @echo ' includecheck - Check for duplicate included header files'
1465 @echo ' export_report - List the usages of all exported symbols'
1466 @echo ' headerdep - Detect inclusion cycles in headers'
1467 @echo ' coccicheck - Check with Coccinelle'
1470 @echo ' nsdeps - Generate missing symbol namespace dependencies'
1472 @echo 'Kernel selftest:'
1473 @echo ' kselftest - Build and run kernel selftest (run as root)'
1474 @echo ' Build, install, and boot kernel before'
1475 @echo ' running kselftest on it'
1476 @echo ' kselftest-clean - Remove all generated kselftest files'
1477 @echo ' kselftest-merge - Merge all the config dependencies of kselftest to existing'
1481 echo 'Devicetree:'; \
1482 echo '* dtbs - Build device tree blobs for enabled boards'; \
1483 echo ' dtbs_install - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1484 echo ' dt_binding_check - Validate device tree binding documents'; \
1485 echo ' dtbs_check - Validate device tree source files';\
1488 @echo 'Userspace tools targets:'
1489 @echo ' use "make tools/help"'
1490 @echo ' or "cd tools; make help"'
1492 @echo 'Kernel packaging:'
1493 @$(MAKE) -f $(srctree)/scripts/Makefile.package help
1495 @echo 'Documentation targets:'
1496 @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1498 @echo 'Architecture specific targets ($(SRCARCH)):'
1499 @$(if $(archhelp),$(archhelp),\
1500 echo ' No architecture specific help defined for $(SRCARCH)')
1503 $(foreach b, $(boards), \
1504 printf " %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1506 @$(if $(board-dirs), \
1507 $(foreach b, $(board-dirs), \
1508 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1509 printf " %-16s - Show all of the above\\n" help-boards; \
1512 @echo ' make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1513 @echo ' make V=2 [targets] 2 => give reason for rebuild of target'
1514 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1515 @echo ' make C=1 [targets] Check re-compiled c source with $$CHECK'
1516 @echo ' (sparse by default)'
1517 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1518 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1519 @echo ' make W=n [targets] Enable extra build checks, n=1,2,3 where'
1520 @echo ' 1: warnings which may be relevant and do not occur too often'
1521 @echo ' 2: warnings which occur quite often but may still be relevant'
1522 @echo ' 3: more obscure warnings, can most likely be ignored'
1523 @echo ' Multiple levels can be combined with W=12 or W=123'
1525 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1526 @echo 'For further info see the ./README file'
1529 help-board-dirs := $(addprefix help-,$(board-dirs))
1531 help-boards: $(help-board-dirs)
1533 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1535 $(help-board-dirs): help-%:
1536 @echo 'Architecture specific targets ($(SRCARCH) $*):'
1537 @$(if $(boards-per-dir), \
1538 $(foreach b, $(boards-per-dir), \
1539 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1543 # Documentation targets
1544 # ---------------------------------------------------------------------------
1545 DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1546 linkcheckdocs dochelp refcheckdocs
1547 PHONY += $(DOC_TARGETS)
1549 $(Q)$(MAKE) $(build)=Documentation $@
1552 # ---------------------------------------------------------------------------
1554 PHONY += scripts_gdb
1555 scripts_gdb: prepare0
1556 $(Q)$(MAKE) $(build)=scripts/gdb
1557 $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1559 ifdef CONFIG_GDB_SCRIPTS
1563 else # KBUILD_EXTMOD
1566 # External module support.
1567 # When building external modules the kernel used as basis is considered
1568 # read-only, and no consistency checks are made and the make
1569 # system is not used on the basis kernel. If updates are required
1570 # in the basis kernel ordinary make commands (without M=...) must
1573 # The following are the only valid targets when building external
1575 # make M=dir clean Delete all automatically generated files
1576 # make M=dir modules Make all modules in specified dir
1577 # make M=dir Same as 'make M=dir modules'
1578 # make M=dir modules_install
1579 # Install the modules built in the module directory
1580 # Assumes install directory is already created
1582 # We are always building modules
1585 PHONY += $(objtree)/Module.symvers
1586 $(objtree)/Module.symvers:
1587 @test -e $(objtree)/Module.symvers || ( \
1589 echo " WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1590 echo " is missing; modules will have no dependencies and modversions."; \
1593 build-dirs := $(KBUILD_EXTMOD)
1595 modules: descend $(objtree)/Module.symvers
1596 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1598 PHONY += modules_install
1599 modules_install: _emodinst_ _emodinst_post
1601 install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1604 $(Q)mkdir -p $(MODLIB)/$(install-dir)
1605 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1607 PHONY += _emodinst_post
1608 _emodinst_post: _emodinst_
1611 clean-dirs := $(KBUILD_EXTMOD)
1612 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps
1616 @echo >&2 '"$(MAKE) /" is no longer supported. Please use "$(MAKE) ./" instead.'
1620 @echo ' Building external modules.'
1621 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1623 @echo ' modules - default target, build the module(s)'
1624 @echo ' modules_install - install the module'
1625 @echo ' clean - remove generated files in module directory only'
1629 endif # KBUILD_EXTMOD
1632 # ---------------------------------------------------------------------------
1633 # To build individual files in subdirectories, you can do like this:
1635 # make foo/bar/baz.s
1637 # The supported suffixes for single-target are listed in 'single-targets'
1639 # To build only under specific subdirectories, you can do like this:
1645 # .ko is special because modpost is needed
1646 single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1647 single-no-ko := $(sort $(patsubst %.ko,%.mod, $(MAKECMDGOALS)))
1649 $(single-ko): single_modpost
1651 $(single-no-ko): descend
1654 ifeq ($(KBUILD_EXTMOD),)
1655 # For the single build of in-tree modules, use a temporary file to avoid
1656 # the situation of modules_install installing an invalid modules.order.
1657 MODORDER := .modules.tmp
1660 PHONY += single_modpost
1661 single_modpost: $(single-no-ko)
1662 $(Q){ $(foreach m, $(single-ko), echo $(extmod-prefix)$m;) } > $(MODORDER)
1663 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1667 export KBUILD_SINGLE_TARGETS := $(addprefix $(extmod-prefix), $(single-no-ko))
1669 # trim unrelated directories
1670 build-dirs := $(foreach d, $(build-dirs), \
1671 $(if $(filter $(d)/%, $(KBUILD_SINGLE_TARGETS)), $(d)))
1675 # Handle descending into subdirectories listed in $(build-dirs)
1676 # Preset locale variables to speed up the build process. Limit locale
1677 # tweaks to this spot to avoid wrong language settings when running
1678 # make menuconfig etc.
1679 # Error messages still appears in the original language
1680 PHONY += descend $(build-dirs)
1681 descend: $(build-dirs)
1682 $(build-dirs): prepare
1683 $(Q)$(MAKE) $(build)=$@ \
1684 single-build=$(if $(filter-out $@/, $(filter $@/%, $(single-no-ko))),1) \
1685 need-builtin=1 need-modorder=1
1687 clean-dirs := $(addprefix _clean_, $(clean-dirs))
1688 PHONY += $(clean-dirs) clean
1690 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1692 clean: $(clean-dirs)
1695 @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1696 \( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1698 -o -name '*.dtb' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1699 -o -name '*.dwo' -o -name '*.lst' \
1700 -o -name '*.su' -o -name '*.mod' \
1701 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1702 -o -name '*.lex.c' -o -name '*.tab.[ch]' \
1703 -o -name '*.asn1.[ch]' \
1704 -o -name '*.symtypes' -o -name 'modules.order' \
1705 -o -name '.tmp_*.o.*' \
1706 -o -name '*.c.[012]*.*' \
1708 -o -name '*.gcno' \) -type f -print | xargs rm -f
1710 # Generate tags for editors
1711 # ---------------------------------------------------------------------------
1712 quiet_cmd_tags = GEN $@
1713 cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1715 tags TAGS cscope gtags: FORCE
1718 # Script to generate missing namespace dependencies
1719 # ---------------------------------------------------------------------------
1722 nsdeps: export KBUILD_NSDEPS=1
1724 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1726 # Scripts to check various things for consistency
1727 # ---------------------------------------------------------------------------
1729 PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1732 find $(srctree)/* $(RCS_FIND_IGNORE) \
1733 -name '*.[hcS]' -type f -print | sort \
1734 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1737 find $(srctree)/* $(RCS_FIND_IGNORE) \
1738 -name '*.[hcS]' -type f -print | sort \
1739 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1742 $(Q)$(BASH) $(srctree)/scripts/$@
1745 $(PERL) $(srctree)/scripts/namespace.pl
1748 $(PERL) $(srctree)/scripts/export_report.pl
1750 PHONY += checkstack kernelrelease kernelversion image_name
1752 # UML needs a little special treatment here. It wants to use the host
1753 # toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
1754 # else wants $(ARCH), including people doing cross-builds, which means
1755 # that $(SUBARCH) doesn't work here.
1757 CHECKSTACK_ARCH := $(SUBARCH)
1759 CHECKSTACK_ARCH := $(ARCH)
1762 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1763 $(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1766 @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1769 @echo $(KERNELVERSION)
1772 @echo $(KBUILD_IMAGE)
1774 # Clear a bunch of variables before executing the submake
1776 ifeq ($(quiet),silent_)
1781 $(Q)mkdir -p $(objtree)/tools
1782 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1785 $(Q)mkdir -p $(objtree)/tools
1786 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1788 # FIXME Should go into a make.lib or something
1789 # ===========================================================================
1791 quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN $(wildcard $(rm-dirs)))
1792 cmd_rmdirs = rm -rf $(rm-dirs)
1794 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
1795 cmd_rmfiles = rm -f $(rm-files)
1797 # Run depmod only if we have System.map and depmod is executable
1798 quiet_cmd_depmod = DEPMOD $(KERNELRELEASE)
1799 cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1802 # read saved command lines for existing targets
1803 existing-targets := $(wildcard $(sort $(targets)))
1805 -include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
1807 endif # config-targets
1809 endif # need-sub-make
1814 # Declare the contents of the PHONY variable as phony. We keep that
1815 # information in a variable so we can use it in if_changed and friends.