1 # SPDX-License-Identifier: GPL-2.0
9 # To see a list of typical targets execute "make help"
10 # More info can be located in ./README
11 # Comments in this file are targeted only to the developer, do not
12 # expect to learn how to build the kernel reading this file.
14 # That's our default target when none is given on the command line
18 # Do not use make's built-in rules and variables
19 # (this increases performance and avoids hard-to-debug behaviour)
22 # Avoid funny character set dependencies
26 export LC_COLLATE LC_NUMERIC
28 # Avoid interference with shell env settings
31 # We are using a recursive build, so we need to do a little thinking
32 # to get the ordering right.
34 # Most importantly: sub-Makefiles should only ever modify files in
35 # their own directory. If in some directory we have a dependency on
36 # a file in another dir (which doesn't happen often, but it's often
37 # unavoidable when linking the built-in.a targets which finally
38 # turn into vmlinux), we will call a sub make in that other dir, and
39 # after that we are sure that everything which is in that other dir
42 # The only cases where we need to modify files which have global
43 # effects are thus separated out and done before the recursive
44 # descending is started. They are now explicitly listed as the
48 # ---------------------------------------------------------------------------
50 # Normally, we echo the whole command before executing it. By making
51 # that echo $($(quiet)$(cmd)), we now have the possibility to set
52 # $(quiet) to choose other forms of output instead, e.g.
54 # quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
55 # cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
57 # If $(quiet) is empty, the whole command will be printed.
58 # If it is set to "quiet_", only the short version will be printed.
59 # If it is set to "silent_", nothing will be printed at all, since
60 # the variable $(silent_cmd_cc_o_c) doesn't exist.
62 # A simple variant is to prefix commands with $(Q) - that's useful
63 # for commands that shall be hidden in non-verbose mode.
67 # If KBUILD_VERBOSE equals 0 then the above command will be hidden.
68 # If KBUILD_VERBOSE equals 1 then the above command is displayed.
70 # To put more focus on warnings, be less verbose as default
71 # Use 'make V=1' to see the full commands
73 ifeq ("$(origin V)", "command line")
80 ifeq ($(KBUILD_VERBOSE),1)
88 # If the user is running make -s (silent mode), suppress echoing of
91 ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
96 export quiet Q KBUILD_VERBOSE
98 # kbuild supports saving output files in a separate directory.
99 # To locate output files in a separate directory two syntaxes are supported.
100 # In both cases the working directory must be the root of the kernel src.
102 # Use "make O=dir/to/store/output/files/"
104 # 2) Set KBUILD_OUTPUT
105 # Set the environment variable KBUILD_OUTPUT to point to the directory
106 # where the output files shall be placed.
107 # export KBUILD_OUTPUT=dir/to/store/output/files/
110 # The O= assignment takes precedence over the KBUILD_OUTPUT environment
113 # KBUILD_SRC is not intended to be used by the regular user (for now),
114 # it is set on invocation of make with KBUILD_OUTPUT or O= specified.
115 ifeq ($(KBUILD_SRC),)
117 # OK, Make called in directory where kernel src resides
118 # Do we want to locate output files in a separate directory?
119 ifeq ("$(origin O)", "command line")
120 KBUILD_OUTPUT := $(O)
123 # Cancel implicit rules on top Makefile
124 $(CURDIR)/Makefile Makefile: ;
126 ifneq ($(words $(subst :, ,$(CURDIR))), 1)
127 $(error main directory cannot contain spaces nor colons)
130 ifneq ($(KBUILD_OUTPUT),)
131 # check that the output directory actually exists
132 saved-output := $(KBUILD_OUTPUT)
133 KBUILD_OUTPUT := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) \
135 $(if $(KBUILD_OUTPUT),, \
136 $(error failed to create output directory "$(saved-output)"))
138 # Look for make include files relative to root of kernel src
140 # This does not become effective immediately because MAKEFLAGS is re-parsed
141 # once after the Makefile is read. It is OK since we are going to invoke
143 MAKEFLAGS += --include-dir=$(CURDIR)
145 PHONY += $(MAKECMDGOALS) sub-make
147 $(filter-out _all sub-make $(CURDIR)/Makefile, $(MAKECMDGOALS)) _all: sub-make
150 # Invoke a second make in the output directory, passing relevant variables
152 $(Q)$(MAKE) -C $(KBUILD_OUTPUT) KBUILD_SRC=$(CURDIR) \
153 -f $(CURDIR)/Makefile $(filter-out _all sub-make,$(MAKECMDGOALS))
155 # Leave processing to above invocation of make
157 endif # ifneq ($(KBUILD_OUTPUT),)
158 endif # ifeq ($(KBUILD_SRC),)
160 # We process the rest of the Makefile if this is the final invocation of make
161 ifeq ($(skip-makefile),)
163 # Do not print "Entering directory ...",
164 # but we want to display it when entering to the output directory
165 # so that IDEs/editors are able to understand relative filenames.
166 MAKEFLAGS += --no-print-directory
168 # Call a source code checker (by default, "sparse") as part of the
171 # Use 'make C=1' to enable checking of only re-compiled files.
172 # Use 'make C=2' to enable checking of *all* source files, regardless
173 # of whether they are re-compiled or not.
175 # See the file "Documentation/dev-tools/sparse.rst" for more details,
176 # including where to get the "sparse" utility.
178 ifeq ("$(origin C)", "command line")
179 KBUILD_CHECKSRC = $(C)
181 ifndef KBUILD_CHECKSRC
185 # Use make M=dir to specify directory of external module to build
186 # Old syntax make ... SUBDIRS=$PWD is still supported
187 # Setting the environment variable KBUILD_EXTMOD take precedence
189 KBUILD_EXTMOD ?= $(SUBDIRS)
192 ifeq ("$(origin M)", "command line")
193 KBUILD_EXTMOD := $(M)
196 ifeq ($(KBUILD_SRC),)
197 # building in the source tree
200 ifeq ($(KBUILD_SRC)/,$(dir $(CURDIR)))
201 # building in a subdirectory of the source tree
204 srctree := $(KBUILD_SRC)
208 export KBUILD_CHECKSRC KBUILD_EXTMOD KBUILD_SRC
214 VPATH := $(srctree)$(if $(KBUILD_EXTMOD),:$(KBUILD_EXTMOD))
216 export srctree objtree VPATH
218 # To make sure we do not include .config for any of the *config targets
219 # catch them early, and hand them over to scripts/kconfig/Makefile
220 # It is allowed to specify more targets when calling make, including
221 # mixing *config targets and build targets.
222 # For example 'make oldconfig all'.
223 # Detect when mixed targets is specified, and make a second invocation
224 # of make so .config is not included in this case either (for *config).
226 version_h := include/generated/uapi/linux/version.h
227 old_version_h := include/linux/version.h
229 clean-targets := %clean mrproper cleandocs
230 no-dot-config-targets := $(clean-targets) \
231 cscope gtags TAGS tags help% %docs check% coccicheck \
232 $(version_h) headers_% archheaders archscripts \
233 %asm-generic kernelversion %src-pkg
234 no-sync-config-targets := $(no-dot-config-targets) install %install \
242 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
243 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
248 ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
249 ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
254 ifneq ($(KBUILD_EXTMOD),)
258 ifeq ($(KBUILD_EXTMOD),)
259 ifneq ($(filter config %config,$(MAKECMDGOALS)),)
261 ifneq ($(words $(MAKECMDGOALS)),1)
267 # For "make -j clean all", "make -j mrproper defconfig all", etc.
268 ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
269 ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
274 # install and modules_install need also be processed one by one
275 ifneq ($(filter install,$(MAKECMDGOALS)),)
276 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
281 ifeq ($(mixed-targets),1)
282 # ===========================================================================
283 # We're called with mixed targets (*config and build targets).
284 # Handle them one by one.
286 PHONY += $(MAKECMDGOALS) __build_one_by_one
288 $(filter-out __build_one_by_one, $(MAKECMDGOALS)): __build_one_by_one
293 for i in $(MAKECMDGOALS); do \
294 $(MAKE) -f $(srctree)/Makefile $$i; \
299 # We need some generic definitions (do not try to remake the file).
300 scripts/Kbuild.include: ;
301 include scripts/Kbuild.include
303 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
304 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
305 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
306 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
308 include scripts/subarch.include
310 # Cross compiling and selecting different set of gcc/bin-utils
311 # ---------------------------------------------------------------------------
313 # When performing cross compilation for other architectures ARCH shall be set
314 # to the target architecture. (See arch/* for the possibilities).
315 # ARCH can be set during invocation of make:
317 # Another way is to have ARCH set in the environment.
318 # The default ARCH is the host where make is executed.
320 # CROSS_COMPILE specify the prefix used for all executables used
321 # during compilation. Only gcc and related bin-utils executables
322 # are prefixed with $(CROSS_COMPILE).
323 # CROSS_COMPILE can be set on the command line
324 # make CROSS_COMPILE=ia64-linux-
325 # Alternatively CROSS_COMPILE can be set in the environment.
326 # Default value for CROSS_COMPILE is not to prefix executables
327 # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
330 # Architecture as present in compile.h
331 UTS_MACHINE := $(ARCH)
334 # Additional ARCH settings for x86
338 ifeq ($(ARCH),x86_64)
342 # Additional ARCH settings for sparc
343 ifeq ($(ARCH),sparc32)
346 ifeq ($(ARCH),sparc64)
350 # Additional ARCH settings for sh
355 KCONFIG_CONFIG ?= .config
356 export KCONFIG_CONFIG
358 # SHELL used by kbuild
359 CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
360 else if [ -x /bin/bash ]; then echo /bin/bash; \
361 else echo sh; fi ; fi)
363 HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
364 HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
365 HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
369 KBUILD_HOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 \
370 -fomit-frame-pointer -std=gnu89 $(HOST_LFS_CFLAGS) \
372 KBUILD_HOSTCXXFLAGS := -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
373 KBUILD_HOSTLDFLAGS := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
374 KBUILD_HOSTLDLIBS := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
376 # Make variables (CC, etc...)
377 AS = $(CROSS_COMPILE)as
378 LD = $(CROSS_COMPILE)ld
379 CC = $(CROSS_COMPILE)gcc
381 AR = $(CROSS_COMPILE)ar
382 NM = $(CROSS_COMPILE)nm
383 STRIP = $(CROSS_COMPILE)strip
384 OBJCOPY = $(CROSS_COMPILE)objcopy
385 OBJDUMP = $(CROSS_COMPILE)objdump
389 GENKSYMS = scripts/genksyms/genksyms
390 INSTALLKERNEL := installkernel
391 DEPMOD = /sbin/depmod
398 CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
399 -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
408 # Use USERINCLUDE when you must reference the UAPI directories only.
410 -I$(srctree)/arch/$(SRCARCH)/include/uapi \
411 -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
412 -I$(srctree)/include/uapi \
413 -I$(objtree)/include/generated/uapi \
414 -include $(srctree)/include/linux/kconfig.h
416 # Use LINUXINCLUDE when you must reference the include/ directory.
417 # Needed to be compatible with the O= option
419 -I$(srctree)/arch/$(SRCARCH)/include \
420 -I$(objtree)/arch/$(SRCARCH)/include/generated \
421 $(if $(KBUILD_SRC), -I$(srctree)/include) \
422 -I$(objtree)/include \
425 KBUILD_AFLAGS := -D__ASSEMBLY__
426 KBUILD_CFLAGS := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
427 -fno-strict-aliasing -fno-common -fshort-wchar \
428 -Werror-implicit-function-declaration \
429 -Wno-format-security \
431 KBUILD_CPPFLAGS := -D__KERNEL__
432 KBUILD_AFLAGS_KERNEL :=
433 KBUILD_CFLAGS_KERNEL :=
434 KBUILD_AFLAGS_MODULE := -DMODULE
435 KBUILD_CFLAGS_MODULE := -DMODULE
436 KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
438 GCC_PLUGINS_CFLAGS :=
440 export ARCH SRCARCH CONFIG_SHELL HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE AS LD CC
441 export CPP AR NM STRIP OBJCOPY OBJDUMP KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS
442 export MAKE LEX YACC AWK GENKSYMS INSTALLKERNEL PERL PYTHON PYTHON2 PYTHON3 UTS_MACHINE
443 export HOSTCXX KBUILD_HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
445 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
446 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
447 export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN
448 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
449 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
450 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
451 export KBUILD_ARFLAGS
453 # When compiling out-of-tree modules, put MODVERDIR in the module
454 # tree rather than in the kernel tree. The kernel tree might
456 export MODVERDIR := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_versions
458 # Files to ignore in find ... statements
460 export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o \
461 -name CVS -o -name .pc -o -name .hg -o -name .git \) \
463 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
464 --exclude CVS --exclude .pc --exclude .hg --exclude .git
466 # ===========================================================================
467 # Rules shared between *config targets and build targets
469 # Basic helpers built in scripts/basic/
470 PHONY += scripts_basic
472 $(Q)$(MAKE) $(build)=scripts/basic
473 $(Q)rm -f .tmp_quiet_recordmcount
475 # To avoid any implicit rule to kick in, define an empty command.
476 scripts/basic/%: scripts_basic ;
478 PHONY += outputmakefile
479 # outputmakefile generates a Makefile in the output directory, if using a
480 # separate output directory. This allows convenient use of make in the
483 ifneq ($(KBUILD_SRC),)
484 $(Q)ln -fsn $(srctree) source
485 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile $(srctree)
488 ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),)
489 ifneq ($(CROSS_COMPILE),)
490 CLANG_TARGET := --target=$(notdir $(CROSS_COMPILE:%-=%))
491 GCC_TOOLCHAIN_DIR := $(dir $(shell which $(LD)))
492 CLANG_PREFIX := --prefix=$(GCC_TOOLCHAIN_DIR)
493 GCC_TOOLCHAIN := $(realpath $(GCC_TOOLCHAIN_DIR)/..)
495 ifneq ($(GCC_TOOLCHAIN),)
496 CLANG_GCC_TC := --gcc-toolchain=$(GCC_TOOLCHAIN)
498 KBUILD_CFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC) $(CLANG_PREFIX)
499 KBUILD_AFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC) $(CLANG_PREFIX)
500 KBUILD_CFLAGS += $(call cc-option, -no-integrated-as)
501 KBUILD_AFLAGS += $(call cc-option, -no-integrated-as)
504 RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
505 RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
506 RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
507 RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
508 RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
509 RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
510 export RETPOLINE_CFLAGS
511 export RETPOLINE_VDSO_CFLAGS
513 KBUILD_CFLAGS += $(call cc-option,-fno-PIE)
514 KBUILD_AFLAGS += $(call cc-option,-fno-PIE)
516 # check for 'asm goto'
517 ifeq ($(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC) $(KBUILD_CFLAGS)), y)
518 CC_HAVE_ASM_GOTO := 1
519 KBUILD_CFLAGS += -DCC_HAVE_ASM_GOTO
520 KBUILD_AFLAGS += -DCC_HAVE_ASM_GOTO
523 # The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
524 # Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
525 # CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
526 # and from include/config/auto.conf.cmd to detect the compiler upgrade.
527 CC_VERSION_TEXT = $(shell $(CC) --version | head -n 1)
529 ifeq ($(config-targets),1)
530 # ===========================================================================
531 # *config targets only - make sure prerequisites are updated, and descend
532 # in scripts/kconfig to make the *config target
534 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
535 # KBUILD_DEFCONFIG may point out an alternative default configuration
536 # used for 'make defconfig'
537 include arch/$(SRCARCH)/Makefile
538 export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
540 config: scripts_basic outputmakefile FORCE
541 $(Q)$(MAKE) $(build)=scripts/kconfig $@
543 %config: scripts_basic outputmakefile FORCE
544 $(Q)$(MAKE) $(build)=scripts/kconfig $@
547 # ===========================================================================
548 # Build targets only - this includes vmlinux, arch specific targets, clean
549 # targets and others. In general all targets except *config targets.
551 # If building an external module we do not care about the all: rule
552 # but instead _all depend on modules
554 ifeq ($(KBUILD_EXTMOD),)
560 # Decide whether to build built-in, modular, or both.
561 # Normally, just do built-in.
566 # If we have only "make modules", don't compile built-in objects.
567 # When we're building modules with modversions, we need to consider
568 # the built-in objects during the descend as well, in order to
569 # make sure the checksums are up to date before we record them.
571 ifeq ($(MAKECMDGOALS),modules)
572 KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
575 # If we have "make <whatever> modules", compile modules
576 # in addition to whatever we do anyway.
577 # Just "make" or "make all" shall build modules as well
579 ifneq ($(filter all _all modules,$(MAKECMDGOALS)),)
583 ifeq ($(MAKECMDGOALS),)
587 export KBUILD_MODULES KBUILD_BUILTIN
589 ifeq ($(KBUILD_EXTMOD),)
590 # Objects we will link into vmlinux / subdirs we need to visit
592 drivers-y := drivers/ sound/ firmware/
597 endif # KBUILD_EXTMOD
599 ifeq ($(dot-config),1)
600 include include/config/auto.conf
603 # The all: target is the default when no target is given on the
605 # This allow a user to issue only 'make' to build a kernel including modules
606 # Defaults to vmlinux, but the arch makefile usually adds further targets
609 CFLAGS_GCOV := -fprofile-arcs -ftest-coverage \
610 $(call cc-option,-fno-tree-loop-im) \
611 $(call cc-disable-warning,maybe-uninitialized,)
614 # The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
615 ifdef CONFIG_FUNCTION_TRACER
616 CC_FLAGS_FTRACE := -pg
619 # The arch Makefile can set ARCH_{CPP,A,C}FLAGS to override the default
620 # values of the respective KBUILD_* variables
624 include arch/$(SRCARCH)/Makefile
626 ifeq ($(dot-config),1)
627 ifeq ($(may-sync-config),1)
628 # Read in dependencies to all Kconfig* files, make sure to run syncconfig if
629 # changes are detected. This should be included after arch/$(SRCARCH)/Makefile
630 # because some architectures define CROSS_COMPILE there.
631 -include include/config/auto.conf.cmd
633 # To avoid any implicit rule to kick in, define an empty command
634 $(KCONFIG_CONFIG) include/config/auto.conf.cmd: ;
636 # The actual configuration files used during the build are stored in
637 # include/generated/ and include/config/. Update them if .config is newer than
638 # include/config/auto.conf (which mirrors .config).
639 include/config/%.conf: $(KCONFIG_CONFIG) include/config/auto.conf.cmd
640 $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
642 # External modules and some install targets need include/generated/autoconf.h
643 # and include/config/auto.conf but do not care if they are up-to-date.
644 # Use auto.conf to trigger the test
645 PHONY += include/config/auto.conf
647 include/config/auto.conf:
648 $(Q)test -e include/generated/autoconf.h -a -e $@ || ( \
650 echo >&2 " ERROR: Kernel configuration is invalid."; \
651 echo >&2 " include/generated/autoconf.h or $@ are missing.";\
652 echo >&2 " Run 'make oldconfig && make prepare' on kernel src to fix it."; \
656 endif # may-sync-config
657 endif # $(dot-config)
659 KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,)
660 KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,)
661 KBUILD_CFLAGS += $(call cc-disable-warning, format-truncation)
662 KBUILD_CFLAGS += $(call cc-disable-warning, format-overflow)
663 KBUILD_CFLAGS += $(call cc-disable-warning, int-in-bool-context)
665 ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
666 KBUILD_CFLAGS += $(call cc-option,-Oz,-Os)
667 KBUILD_CFLAGS += $(call cc-disable-warning,maybe-uninitialized,)
669 ifdef CONFIG_PROFILE_ALL_BRANCHES
670 KBUILD_CFLAGS += -O2 $(call cc-disable-warning,maybe-uninitialized,)
676 KBUILD_CFLAGS += $(call cc-ifversion, -lt, 0409, \
677 $(call cc-disable-warning,maybe-uninitialized,))
679 # Tell gcc to never replace conditional load with a non-conditional one
680 KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
682 include scripts/Makefile.kcov
683 include scripts/Makefile.gcc-plugins
685 ifdef CONFIG_READABLE_ASM
686 # Disable optimizations that make assembler listings hard to read.
687 # reorder blocks reorders the control in the function
688 # ipa clone creates specialized cloned functions
689 # partial inlining inlines only parts of functions
690 KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
691 $(call cc-option,-fno-ipa-cp-clone,) \
692 $(call cc-option,-fno-partial-inlining)
695 ifneq ($(CONFIG_FRAME_WARN),0)
696 KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
699 stackp-flags-$(CONFIG_CC_HAS_STACKPROTECTOR_NONE) := -fno-stack-protector
700 stackp-flags-$(CONFIG_STACKPROTECTOR) := -fstack-protector
701 stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG) := -fstack-protector-strong
703 KBUILD_CFLAGS += $(stackp-flags-y)
705 ifdef CONFIG_CC_IS_CLANG
706 KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
707 KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier)
708 KBUILD_CFLAGS += $(call cc-disable-warning, gnu)
709 KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
710 # Quiet clang warning: comparison of unsigned expression < 0 is always false
711 KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare)
712 # CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
713 # source of a reference will be _MergedGlobals and not on of the whitelisted names.
714 # See modpost pattern 2
715 KBUILD_CFLAGS += $(call cc-option, -mno-global-merge,)
716 KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior)
719 # These warnings generated too much noise in a regular build.
720 # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
721 KBUILD_CFLAGS += -Wno-unused-but-set-variable
724 KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
725 ifdef CONFIG_FRAME_POINTER
726 KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
728 # Some targets (ARM with Thumb2, for example), can't be built with frame
729 # pointers. For those, we don't have FUNCTION_TRACER automatically
730 # select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
731 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
732 # -fomit-frame-pointer with FUNCTION_TRACER.
733 ifndef CONFIG_FUNCTION_TRACER
734 KBUILD_CFLAGS += -fomit-frame-pointer
738 KBUILD_CFLAGS += $(call cc-option, -fno-var-tracking-assignments)
740 ifdef CONFIG_DEBUG_INFO
741 ifdef CONFIG_DEBUG_INFO_SPLIT
742 KBUILD_CFLAGS += $(call cc-option, -gsplit-dwarf, -g)
746 KBUILD_AFLAGS += -Wa,-gdwarf-2
748 ifdef CONFIG_DEBUG_INFO_DWARF4
749 KBUILD_CFLAGS += $(call cc-option, -gdwarf-4,)
752 ifdef CONFIG_DEBUG_INFO_REDUCED
753 KBUILD_CFLAGS += $(call cc-option, -femit-struct-debug-baseonly) \
754 $(call cc-option,-fno-var-tracking)
757 ifdef CONFIG_FUNCTION_TRACER
758 ifdef CONFIG_FTRACE_MCOUNT_RECORD
759 # gcc 5 supports generating the mcount tables directly
760 ifeq ($(call cc-option-yn,-mrecord-mcount),y)
761 CC_FLAGS_FTRACE += -mrecord-mcount
762 export CC_USING_RECORD_MCOUNT := 1
764 ifdef CONFIG_HAVE_NOP_MCOUNT
765 ifeq ($(call cc-option-yn, -mnop-mcount),y)
766 CC_FLAGS_FTRACE += -mnop-mcount
767 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
771 ifdef CONFIG_HAVE_FENTRY
772 ifeq ($(call cc-option-yn, -mfentry),y)
773 CC_FLAGS_FTRACE += -mfentry
774 CC_FLAGS_USING += -DCC_USING_FENTRY
777 export CC_FLAGS_FTRACE
778 KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
779 KBUILD_AFLAGS += $(CC_FLAGS_USING)
780 ifdef CONFIG_DYNAMIC_FTRACE
781 ifdef CONFIG_HAVE_C_RECORDMCOUNT
782 BUILD_C_RECORDMCOUNT := y
783 export BUILD_C_RECORDMCOUNT
788 # We trigger additional mismatches with less inlining
789 ifdef CONFIG_DEBUG_SECTION_MISMATCH
790 KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
793 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
794 KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
795 LDFLAGS_vmlinux += --gc-sections
798 # arch Makefile may override CC so keep this after arch Makefile is included
799 NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
801 # warn about C99 declaration after statement
802 KBUILD_CFLAGS += -Wdeclaration-after-statement
804 # Variable Length Arrays (VLAs) should not be used anywhere in the kernel
805 KBUILD_CFLAGS += $(call cc-option,-Wvla)
807 # disable pointer signed / unsigned warnings in gcc 4.0
808 KBUILD_CFLAGS += -Wno-pointer-sign
810 # disable stringop warnings in gcc 8+
811 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
813 # disable invalid "can't wrap" optimizations for signed / pointers
814 KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow)
816 # clang sets -fmerge-all-constants by default as optimization, but this
817 # is non-conforming behavior for C and in fact breaks the kernel, so we
818 # need to disable it here generally.
819 KBUILD_CFLAGS += $(call cc-option,-fno-merge-all-constants)
821 # for gcc -fno-merge-all-constants disables everything, but it is fine
822 # to have actual conforming behavior enabled.
823 KBUILD_CFLAGS += $(call cc-option,-fmerge-constants)
825 # Make sure -fstack-check isn't enabled (like gentoo apparently did)
826 KBUILD_CFLAGS += $(call cc-option,-fno-stack-check,)
828 # conserve stack if available
829 KBUILD_CFLAGS += $(call cc-option,-fconserve-stack)
831 # disallow errors like 'EXPORT_GPL(foo);' with missing header
832 KBUILD_CFLAGS += $(call cc-option,-Werror=implicit-int)
834 # require functions to have arguments in prototypes, not empty 'int foo()'
835 KBUILD_CFLAGS += $(call cc-option,-Werror=strict-prototypes)
837 # Prohibit date/time macros, which would make the build non-deterministic
838 KBUILD_CFLAGS += $(call cc-option,-Werror=date-time)
840 # enforce correct pointer usage
841 KBUILD_CFLAGS += $(call cc-option,-Werror=incompatible-pointer-types)
843 # Require designated initializers for all marked structures
844 KBUILD_CFLAGS += $(call cc-option,-Werror=designated-init)
846 # change __FILE__ to the relative path from the srctree
847 KBUILD_CFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
849 # use the deterministic mode of AR if available
850 KBUILD_ARFLAGS := $(call ar-option,D)
852 include scripts/Makefile.kasan
853 include scripts/Makefile.extrawarn
854 include scripts/Makefile.ubsan
856 # Add any arch overrides and user supplied CPPFLAGS, AFLAGS and CFLAGS as the
858 KBUILD_CPPFLAGS += $(ARCH_CPPFLAGS) $(KCPPFLAGS)
859 KBUILD_AFLAGS += $(ARCH_AFLAGS) $(KAFLAGS)
860 KBUILD_CFLAGS += $(ARCH_CFLAGS) $(KCFLAGS)
862 # Use --build-id when available.
863 LDFLAGS_BUILD_ID := $(call ld-option, --build-id)
864 KBUILD_LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID)
865 LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)
867 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
868 LDFLAGS_vmlinux += $(call ld-option, -X,)
871 # insure the checker run with the right endianness
872 CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
874 # the checker needs the correct machine size
875 CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
877 # Default kernel image to build when no specific target is given.
878 # KBUILD_IMAGE may be overruled on the command line or
879 # set in the environment
880 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
882 export KBUILD_IMAGE ?= vmlinux
885 # INSTALL_PATH specifies where to place the updated kernel and system map
886 # images. Default is /boot, but you can set it to other values
887 export INSTALL_PATH ?= /boot
890 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
891 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
892 # an argument if needed. Otherwise it defaults to the kernel install path
894 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
897 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
898 # relocations required by build roots. This is not defined in the
899 # makefile but the argument can be passed to make if needed.
902 MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
906 # INSTALL_MOD_STRIP, if defined, will cause modules to be
907 # stripped after they are installed. If INSTALL_MOD_STRIP is '1', then
908 # the default option --strip-debug will be used. Otherwise,
909 # INSTALL_MOD_STRIP value will be used as the options to the strip command.
911 ifdef INSTALL_MOD_STRIP
912 ifeq ($(INSTALL_MOD_STRIP),1)
913 mod_strip_cmd = $(STRIP) --strip-debug
915 mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
916 endif # INSTALL_MOD_STRIP=1
919 endif # INSTALL_MOD_STRIP
922 # CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
923 # after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
924 # or CONFIG_MODULE_COMPRESS_XZ.
926 mod_compress_cmd = true
927 ifdef CONFIG_MODULE_COMPRESS
928 ifdef CONFIG_MODULE_COMPRESS_GZIP
929 mod_compress_cmd = gzip -n -f
930 endif # CONFIG_MODULE_COMPRESS_GZIP
931 ifdef CONFIG_MODULE_COMPRESS_XZ
932 mod_compress_cmd = xz -f
933 endif # CONFIG_MODULE_COMPRESS_XZ
934 endif # CONFIG_MODULE_COMPRESS
935 export mod_compress_cmd
937 # Select initial ramdisk compression format, default is gzip(1).
938 # This shall be used by the dracut(8) tool while creating an initramfs image.
940 INITRD_COMPRESS-y := gzip
941 INITRD_COMPRESS-$(CONFIG_RD_BZIP2) := bzip2
942 INITRD_COMPRESS-$(CONFIG_RD_LZMA) := lzma
943 INITRD_COMPRESS-$(CONFIG_RD_XZ) := xz
944 INITRD_COMPRESS-$(CONFIG_RD_LZO) := lzo
945 INITRD_COMPRESS-$(CONFIG_RD_LZ4) := lz4
946 # do not export INITRD_COMPRESS, since we didn't actually
947 # choose a sane default compression above.
948 # export INITRD_COMPRESS := $(INITRD_COMPRESS-y)
950 ifdef CONFIG_MODULE_SIG_ALL
951 $(eval $(call config_filename,MODULE_SIG_KEY))
953 mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
959 ifdef CONFIG_STACK_VALIDATION
960 has_libelf := $(call try-run,\
961 echo "int main() {}" | $(HOSTCC) -xc -o /dev/null -lelf -,1,0)
962 ifeq ($(has_libelf),1)
963 objtool_target := tools/objtool FORCE
965 ifdef CONFIG_UNWINDER_ORC
966 $(error "Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel")
968 $(warning "Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel")
970 SKIP_STACK_VALIDATION := 1
971 export SKIP_STACK_VALIDATION
976 ifeq ($(KBUILD_EXTMOD),)
977 core-y += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
979 vmlinux-dirs := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
980 $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
981 $(net-y) $(net-m) $(libs-y) $(libs-m) $(virt-y)))
983 vmlinux-alldirs := $(sort $(vmlinux-dirs) $(patsubst %/,%,$(filter %/, \
984 $(init-) $(core-) $(drivers-) $(net-) $(libs-) $(virt-))))
986 init-y := $(patsubst %/, %/built-in.a, $(init-y))
987 core-y := $(patsubst %/, %/built-in.a, $(core-y))
988 drivers-y := $(patsubst %/, %/built-in.a, $(drivers-y))
989 net-y := $(patsubst %/, %/built-in.a, $(net-y))
990 libs-y1 := $(patsubst %/, %/lib.a, $(libs-y))
991 libs-y2 := $(patsubst %/, %/built-in.a, $(filter-out %.a, $(libs-y)))
992 virt-y := $(patsubst %/, %/built-in.a, $(virt-y))
994 # Externally visible symbols (used by link-vmlinux.sh)
995 export KBUILD_VMLINUX_INIT := $(head-y) $(init-y)
996 export KBUILD_VMLINUX_MAIN := $(core-y) $(libs-y2) $(drivers-y) $(net-y) $(virt-y)
997 export KBUILD_VMLINUX_LIBS := $(libs-y1)
998 export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
999 export LDFLAGS_vmlinux
1000 # used by scripts/package/Makefile
1001 export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) arch Documentation include samples scripts tools)
1003 vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_INIT) $(KBUILD_VMLINUX_MAIN) $(KBUILD_VMLINUX_LIBS)
1005 # Recurse until adjust_autoksyms.sh is satisfied
1006 PHONY += autoksyms_recursive
1007 autoksyms_recursive: $(vmlinux-deps)
1008 ifdef CONFIG_TRIM_UNUSED_KSYMS
1009 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1010 "$(MAKE) -f $(srctree)/Makefile vmlinux"
1013 # For the kernel to actually contain only the needed exported symbols,
1014 # we have to build modules as well to determine what those symbols are.
1015 # (this can be evaluated only once include/config/auto.conf has been included)
1016 ifdef CONFIG_TRIM_UNUSED_KSYMS
1020 autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1023 $(Q)mkdir -p $(dir $@)
1026 ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1028 # Final link of vmlinux with optional arch pass after final link
1029 cmd_link-vmlinux = \
1030 $(CONFIG_SHELL) $< $(LD) $(KBUILD_LDFLAGS) $(LDFLAGS_vmlinux) ; \
1031 $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1033 vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1034 ifdef CONFIG_HEADERS_CHECK
1035 $(Q)$(MAKE) -f $(srctree)/Makefile headers_check
1037 ifdef CONFIG_GDB_SCRIPTS
1038 $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1040 +$(call if_changed,link-vmlinux)
1042 # Build samples along the rest of the kernel. This needs headers_install.
1043 ifdef CONFIG_SAMPLES
1044 vmlinux-dirs += samples
1045 samples: headers_install
1048 # The actual objects are generated when descending,
1049 # make sure no implicit rule kicks in
1050 $(sort $(vmlinux-deps)): $(vmlinux-dirs) ;
1052 # Handle descending into subdirectories listed in $(vmlinux-dirs)
1053 # Preset locale variables to speed up the build process. Limit locale
1054 # tweaks to this spot to avoid wrong language settings when running
1055 # make menuconfig etc.
1056 # Error messages still appears in the original language
1058 PHONY += $(vmlinux-dirs)
1059 $(vmlinux-dirs): prepare scripts
1060 $(Q)$(MAKE) $(build)=$@ need-builtin=1
1062 define filechk_kernel.release
1063 echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1066 # Store (new) KERNELRELEASE string in include/config/kernel.release
1067 include/config/kernel.release: $(srctree)/Makefile FORCE
1068 $(call filechk,kernel.release)
1070 # Additional helpers built in scripts/
1071 # Carefully list dependencies so we do not try to build scripts twice
1074 scripts: scripts_basic scripts_dtc asm-generic gcc-plugins $(autoksyms_h)
1075 $(Q)$(MAKE) $(build)=$(@)
1077 # Things we need to do before we recursively start building the kernel
1078 # or the modules are listed in "prepare".
1079 # A multi level approach is used. prepareN is processed before prepareN-1.
1080 # archprepare is used in arch Makefiles and when processed asm symlink,
1081 # version.h and scripts_basic is processed / created.
1083 # Listed in dependency order
1084 PHONY += prepare archprepare macroprepare prepare0 prepare1 prepare2 prepare3
1086 # prepare3 is used to check if we are building in a separate output directory,
1088 # 1) Check that make has not been executed in the kernel src $(srctree)
1089 prepare3: include/config/kernel.release
1090 ifneq ($(KBUILD_SRC),)
1091 @$(kecho) ' Using $(srctree) as source for kernel'
1092 $(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \
1093 echo >&2 " $(srctree) is not clean, please run 'make mrproper'"; \
1094 echo >&2 " in the '$(srctree)' directory.";\
1099 # prepare2 creates a makefile if using a separate output directory.
1100 # From this point forward, .config has been reprocessed, so any rules
1101 # that need to depend on updated CONFIG_* values can be checked here.
1102 prepare2: prepare3 outputmakefile asm-generic
1104 prepare1: prepare2 $(version_h) $(autoksyms_h) include/generated/utsrelease.h
1107 macroprepare: prepare1 archmacros
1109 archprepare: archheaders archscripts macroprepare scripts_basic
1111 prepare0: archprepare gcc-plugins
1112 $(Q)$(MAKE) $(build)=.
1114 # All the preparing..
1115 prepare: prepare0 prepare-objtool
1117 # Support for using generic headers in asm-generic
1118 PHONY += asm-generic uapi-asm-generic
1119 asm-generic: uapi-asm-generic
1120 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
1121 src=asm obj=arch/$(SRCARCH)/include/generated/asm
1123 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
1124 src=uapi/asm obj=arch/$(SRCARCH)/include/generated/uapi/asm
1126 PHONY += prepare-objtool
1127 prepare-objtool: $(objtool_target)
1129 # Generate some files
1130 # ---------------------------------------------------------------------------
1132 # KERNELRELEASE can change from a few different places, meaning version.h
1133 # needs to be updated, so this check is forced on all builds
1136 define filechk_utsrelease.h
1137 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1138 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1141 (echo \#define UTS_RELEASE \"$(KERNELRELEASE)\";)
1144 define filechk_version.h
1145 (echo \#define LINUX_VERSION_CODE $(shell \
1146 expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1147 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))';)
1151 $(call filechk,version.h)
1152 $(Q)rm -f $(old_version_h)
1154 include/generated/utsrelease.h: include/config/kernel.release FORCE
1155 $(call filechk,utsrelease.h)
1159 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1160 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1162 # ---------------------------------------------------------------------------
1165 #Default location for installed headers
1166 export INSTALL_HDR_PATH = $(objtree)/usr
1168 # If we do an all arch process set dst to include/arch-$(SRCARCH)
1169 hdr-dst = $(if $(KBUILD_HEADERS), dst=include/arch-$(SRCARCH), dst=include)
1171 PHONY += archheaders
1174 PHONY += archscripts
1181 __headers: $(version_h) scripts_basic uapi-asm-generic archheaders archscripts
1182 $(Q)$(MAKE) $(build)=scripts build_unifdef
1184 PHONY += headers_install_all
1185 headers_install_all:
1186 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh install
1188 PHONY += headers_install
1189 headers_install: __headers
1190 $(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1191 $(error Headers not exportable for the $(SRCARCH) architecture))
1192 $(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include
1193 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi $(hdr-dst)
1195 PHONY += headers_check_all
1196 headers_check_all: headers_install_all
1197 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh check
1199 PHONY += headers_check
1200 headers_check: headers_install
1201 $(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include HDRCHECK=1
1202 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi $(hdr-dst) HDRCHECK=1
1204 # ---------------------------------------------------------------------------
1209 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1211 PHONY += kselftest-clean
1213 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests clean
1215 PHONY += kselftest-merge
1217 $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1218 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/kconfig/merge_config.sh \
1219 -m $(objtree)/.config \
1220 $(srctree)/tools/testing/selftests/*/config
1221 +$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1223 # ---------------------------------------------------------------------------
1226 ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1227 dtstree := arch/$(SRCARCH)/boot/dts
1232 %.dtb: prepare3 scripts_dtc
1233 $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1235 PHONY += dtbs dtbs_install
1236 dtbs: prepare3 scripts_dtc
1237 $(Q)$(MAKE) $(build)=$(dtstree)
1240 $(Q)$(MAKE) $(dtbinst)=$(dtstree)
1242 ifdef CONFIG_OF_EARLY_FLATTREE
1248 PHONY += scripts_dtc
1249 scripts_dtc: scripts_basic
1250 $(Q)$(MAKE) $(build)=scripts/dtc
1252 # ---------------------------------------------------------------------------
1255 ifdef CONFIG_MODULES
1257 # By default, build modules as well
1263 # A module can be listed more than once in obj-m resulting in
1264 # duplicate lines in modules.order files. Those are removed
1265 # using awk while concatenating to the final file.
1268 modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux) modules.builtin
1269 $(Q)$(AWK) '!x[$$0]++' $(vmlinux-dirs:%=$(objtree)/%/modules.order) > $(objtree)/modules.order
1270 @$(kecho) ' Building modules, stage 2.';
1271 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1273 modules.builtin: $(vmlinux-dirs:%=%/modules.builtin)
1274 $(Q)$(AWK) '!x[$$0]++' $^ > $(objtree)/modules.builtin
1276 %/modules.builtin: include/config/auto.conf include/config/tristate.conf
1277 $(Q)$(MAKE) $(modbuiltin)=$*
1280 # Target to prepare building external modules
1281 PHONY += modules_prepare
1282 modules_prepare: prepare scripts
1284 # Target to install modules
1285 PHONY += modules_install
1286 modules_install: _modinst_ _modinst_post
1290 @rm -rf $(MODLIB)/kernel
1291 @rm -f $(MODLIB)/source
1292 @mkdir -p $(MODLIB)/kernel
1293 @ln -s $(abspath $(srctree)) $(MODLIB)/source
1294 @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
1295 rm -f $(MODLIB)/build ; \
1296 ln -s $(CURDIR) $(MODLIB)/build ; \
1298 @cp -f $(objtree)/modules.order $(MODLIB)/
1299 @cp -f $(objtree)/modules.builtin $(MODLIB)/
1300 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1302 # This depmod is only for convenience to give the initial
1303 # boot a modules.dep even before / is mounted read-write. However the
1304 # boot script depmod is the master version.
1305 PHONY += _modinst_post
1306 _modinst_post: _modinst_
1309 ifeq ($(CONFIG_MODULE_SIG), y)
1310 PHONY += modules_sign
1312 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1315 else # CONFIG_MODULES
1317 # Modules not configured
1318 # ---------------------------------------------------------------------------
1320 PHONY += modules modules_install
1321 modules modules_install:
1323 @echo >&2 "The present kernel configuration has modules disabled."
1324 @echo >&2 "Type 'make config' and enable loadable module support."
1325 @echo >&2 "Then build a kernel with module support enabled."
1329 endif # CONFIG_MODULES
1332 # Cleaning is done on three levels.
1333 # make clean Delete most generated files
1334 # Leave enough to build external modules
1335 # make mrproper Delete the current configuration, and all generated files
1336 # make distclean Remove editor backup files, patch leftover files and the like
1338 # Directories & files removed with 'make clean'
1339 CLEAN_DIRS += $(MODVERDIR) include/ksym
1341 # Directories & files removed with 'make mrproper'
1342 MRPROPER_DIRS += include/config usr/include include/generated \
1343 arch/*/include/generated .tmp_objdiff
1344 MRPROPER_FILES += .config .config.old .version \
1345 Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS \
1346 signing_key.pem signing_key.priv signing_key.x509 \
1347 x509.genkey extra_certificates signing_key.x509.keyid \
1348 signing_key.x509.signer vmlinux-gdb.py
1350 # clean - Delete most, but leave enough to build external modules
1352 clean: rm-dirs := $(CLEAN_DIRS)
1353 clean: rm-files := $(CLEAN_FILES)
1354 clean-dirs := $(addprefix _clean_, . $(vmlinux-alldirs) Documentation samples)
1356 PHONY += $(clean-dirs) clean archclean vmlinuxclean
1358 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1361 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1362 $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1364 clean: archclean vmlinuxclean
1366 # mrproper - Delete all generated files, including .config
1368 mrproper: rm-dirs := $(wildcard $(MRPROPER_DIRS))
1369 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1370 mrproper-dirs := $(addprefix _mrproper_,scripts)
1372 PHONY += $(mrproper-dirs) mrproper archmrproper
1374 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1376 mrproper: clean archmrproper $(mrproper-dirs)
1385 @find $(srctree) $(RCS_FIND_IGNORE) \
1386 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1387 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1388 -o -name 'core' \) \
1389 -type f -print | xargs rm -f
1392 # Packaging of the kernel to various formats
1393 # ---------------------------------------------------------------------------
1394 package-dir := scripts/package
1397 $(Q)$(MAKE) $(build)=$(package-dir) $@
1398 %pkg: include/config/kernel.release FORCE
1399 $(Q)$(MAKE) $(build)=$(package-dir) $@
1402 # Brief documentation of the typical targets used
1403 # ---------------------------------------------------------------------------
1405 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1406 boards := $(sort $(notdir $(boards)))
1407 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1408 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1412 @echo 'Cleaning targets:'
1413 @echo ' clean - Remove most generated files but keep the config and'
1414 @echo ' enough build support to build external modules'
1415 @echo ' mrproper - Remove all generated files + config + various backup files'
1416 @echo ' distclean - mrproper + remove editor backup and patch files'
1418 @echo 'Configuration targets:'
1419 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1421 @echo 'Other generic targets:'
1422 @echo ' all - Build all targets marked with [*]'
1423 @echo '* vmlinux - Build the bare kernel'
1424 @echo '* modules - Build all modules'
1425 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1426 @echo ' dir/ - Build all files in dir and below'
1427 @echo ' dir/file.[ois] - Build specified target only'
1428 @echo ' dir/file.ll - Build the LLVM assembly file'
1429 @echo ' (requires compiler support for LLVM assembly generation)'
1430 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1431 @echo ' (requires a recent binutils and recent build (System.map))'
1432 @echo ' dir/file.ko - Build module including final link'
1433 @echo ' modules_prepare - Set up for building external modules'
1434 @echo ' tags/TAGS - Generate tags file for editors'
1435 @echo ' cscope - Generate cscope index'
1436 @echo ' gtags - Generate GNU GLOBAL index'
1437 @echo ' kernelrelease - Output the release version string (use with make -s)'
1438 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1439 @echo ' image_name - Output the image name (use with make -s)'
1440 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1441 echo ' (default: $(INSTALL_HDR_PATH))'; \
1443 @echo 'Static analysers:'
1444 @echo ' checkstack - Generate a list of stack hogs'
1445 @echo ' namespacecheck - Name space analysis on compiled kernel'
1446 @echo ' versioncheck - Sanity check on version.h usage'
1447 @echo ' includecheck - Check for duplicate included header files'
1448 @echo ' export_report - List the usages of all exported symbols'
1449 @echo ' headers_check - Sanity check on exported headers'
1450 @echo ' headerdep - Detect inclusion cycles in headers'
1451 @echo ' coccicheck - Check with Coccinelle'
1453 @echo 'Kernel selftest:'
1454 @echo ' kselftest - Build and run kernel selftest (run as root)'
1455 @echo ' Build, install, and boot kernel before'
1456 @echo ' running kselftest on it'
1457 @echo ' kselftest-clean - Remove all generated kselftest files'
1458 @echo ' kselftest-merge - Merge all the config dependencies of kselftest to existing'
1462 echo 'Devicetree:'; \
1463 echo '* dtbs - Build device tree blobs for enabled boards'; \
1464 echo ' dtbs_install - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1467 @echo 'Userspace tools targets:'
1468 @echo ' use "make tools/help"'
1469 @echo ' or "cd tools; make help"'
1471 @echo 'Kernel packaging:'
1472 @$(MAKE) $(build)=$(package-dir) help
1474 @echo 'Documentation targets:'
1475 @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1477 @echo 'Architecture specific targets ($(SRCARCH)):'
1478 @$(if $(archhelp),$(archhelp),\
1479 echo ' No architecture specific help defined for $(SRCARCH)')
1482 $(foreach b, $(boards), \
1483 printf " %-24s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1485 @$(if $(board-dirs), \
1486 $(foreach b, $(board-dirs), \
1487 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1488 printf " %-16s - Show all of the above\\n" help-boards; \
1491 @echo ' make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1492 @echo ' make V=2 [targets] 2 => give reason for rebuild of target'
1493 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1494 @echo ' make C=1 [targets] Check re-compiled c source with $$CHECK (sparse by default)'
1495 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1496 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1497 @echo ' make W=n [targets] Enable extra gcc checks, n=1,2,3 where'
1498 @echo ' 1: warnings which may be relevant and do not occur too often'
1499 @echo ' 2: warnings which occur quite often but may still be relevant'
1500 @echo ' 3: more obscure warnings, can most likely be ignored'
1501 @echo ' Multiple levels can be combined with W=12 or W=123'
1503 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1504 @echo 'For further info see the ./README file'
1507 help-board-dirs := $(addprefix help-,$(board-dirs))
1509 help-boards: $(help-board-dirs)
1511 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1513 $(help-board-dirs): help-%:
1514 @echo 'Architecture specific targets ($(SRCARCH) $*):'
1515 @$(if $(boards-per-dir), \
1516 $(foreach b, $(boards-per-dir), \
1517 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1521 # Documentation targets
1522 # ---------------------------------------------------------------------------
1523 DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1524 linkcheckdocs dochelp refcheckdocs
1525 PHONY += $(DOC_TARGETS)
1526 $(DOC_TARGETS): scripts_basic FORCE
1527 $(Q)$(MAKE) $(build)=Documentation $@
1529 else # KBUILD_EXTMOD
1532 # External module support.
1533 # When building external modules the kernel used as basis is considered
1534 # read-only, and no consistency checks are made and the make
1535 # system is not used on the basis kernel. If updates are required
1536 # in the basis kernel ordinary make commands (without M=...) must
1539 # The following are the only valid targets when building external
1541 # make M=dir clean Delete all automatically generated files
1542 # make M=dir modules Make all modules in specified dir
1543 # make M=dir Same as 'make M=dir modules'
1544 # make M=dir modules_install
1545 # Install the modules built in the module directory
1546 # Assumes install directory is already created
1548 # We are always building modules
1550 PHONY += crmodverdir
1554 PHONY += $(objtree)/Module.symvers
1555 $(objtree)/Module.symvers:
1556 @test -e $(objtree)/Module.symvers || ( \
1558 echo " WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1559 echo " is missing; modules will have no dependencies and modversions."; \
1562 module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
1563 PHONY += $(module-dirs) modules
1564 $(module-dirs): crmodverdir $(objtree)/Module.symvers
1565 $(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@)
1567 modules: $(module-dirs)
1568 @$(kecho) ' Building modules, stage 2.';
1569 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1571 PHONY += modules_install
1572 modules_install: _emodinst_ _emodinst_post
1574 install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1577 $(Q)mkdir -p $(MODLIB)/$(install-dir)
1578 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1580 PHONY += _emodinst_post
1581 _emodinst_post: _emodinst_
1584 clean-dirs := $(addprefix _clean_,$(KBUILD_EXTMOD))
1586 PHONY += $(clean-dirs) clean
1588 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1590 clean: rm-dirs := $(MODVERDIR)
1591 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers
1595 @echo ' Building external modules.'
1596 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1598 @echo ' modules - default target, build the module(s)'
1599 @echo ' modules_install - install the module'
1600 @echo ' clean - remove generated files in module directory only'
1604 PHONY += prepare scripts
1607 endif # KBUILD_EXTMOD
1609 clean: $(clean-dirs)
1612 @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1613 \( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1614 -o -name '*.ko.*' -o -name '*.dtb' -o -name '*.dtb.S' \
1615 -o -name '*.dwo' -o -name '*.lst' \
1617 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1618 -o -name '*.lex.c' -o -name '*.tab.[ch]' \
1619 -o -name '*.asn1.[ch]' \
1620 -o -name '*.symtypes' -o -name 'modules.order' \
1621 -o -name modules.builtin -o -name '.tmp_*.o.*' \
1622 -o -name '*.c.[012]*.*' \
1624 -o -name '*.gcno' \) -type f -print | xargs rm -f
1626 # Generate tags for editors
1627 # ---------------------------------------------------------------------------
1628 quiet_cmd_tags = GEN $@
1629 cmd_tags = $(CONFIG_SHELL) $(srctree)/scripts/tags.sh $@
1631 tags TAGS cscope gtags: FORCE
1634 # Scripts to check various things for consistency
1635 # ---------------------------------------------------------------------------
1637 PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1640 find $(srctree)/* $(RCS_FIND_IGNORE) \
1641 -name '*.[hcS]' -type f -print | sort \
1642 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1645 find $(srctree)/* $(RCS_FIND_IGNORE) \
1646 -name '*.[hcS]' -type f -print | sort \
1647 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1650 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/$@
1653 $(PERL) $(srctree)/scripts/namespace.pl
1656 $(PERL) $(srctree)/scripts/export_report.pl
1658 PHONY += checkstack kernelrelease kernelversion image_name
1660 # UML needs a little special treatment here. It wants to use the host
1661 # toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
1662 # else wants $(ARCH), including people doing cross-builds, which means
1663 # that $(SUBARCH) doesn't work here.
1665 CHECKSTACK_ARCH := $(SUBARCH)
1667 CHECKSTACK_ARCH := $(ARCH)
1670 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1671 $(PERL) $(src)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1674 @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1677 @echo $(KERNELVERSION)
1680 @echo $(KBUILD_IMAGE)
1682 # Clear a bunch of variables before executing the submake
1684 $(Q)mkdir -p $(objtree)/tools
1685 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(src)/tools/
1688 $(Q)mkdir -p $(objtree)/tools
1689 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(src)/tools/ $*
1692 # ---------------------------------------------------------------------------
1693 # Single targets are compatible with:
1694 # - build with mixed source and output
1695 # - build with separate output dir 'make O=...'
1696 # - external modules
1698 # target-dir => where to store outputfile
1699 # build-dir => directory in kernel source tree to use
1701 ifeq ($(KBUILD_EXTMOD),)
1702 build-dir = $(patsubst %/,%,$(dir $@))
1703 target-dir = $(dir $@)
1705 zap-slash=$(filter-out .,$(patsubst %/,%,$(dir $@)))
1706 build-dir = $(KBUILD_EXTMOD)$(if $(zap-slash),/$(zap-slash))
1707 target-dir = $(if $(KBUILD_EXTMOD),$(dir $<),$(dir $@))
1710 %.s: %.c prepare scripts FORCE
1711 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1712 %.i: %.c prepare scripts FORCE
1713 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1714 %.o: %.c prepare scripts FORCE
1715 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1716 %.lst: %.c prepare scripts FORCE
1717 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1718 %.s: %.S prepare scripts FORCE
1719 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1720 %.o: %.S prepare scripts FORCE
1721 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1722 %.symtypes: %.c prepare scripts FORCE
1723 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1724 %.ll: %.c prepare scripts FORCE
1725 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1728 /: prepare scripts FORCE
1730 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1731 $(build)=$(build-dir)
1732 # Make sure the latest headers are built for Documentation
1733 Documentation/ samples/: headers_install
1734 %/: prepare scripts FORCE
1736 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1737 $(build)=$(build-dir)
1738 %.ko: prepare scripts FORCE
1740 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1741 $(build)=$(build-dir) $(@:.ko=.o)
1742 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1744 # FIXME Should go into a make.lib or something
1745 # ===========================================================================
1747 quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN $(wildcard $(rm-dirs)))
1748 cmd_rmdirs = rm -rf $(rm-dirs)
1750 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
1751 cmd_rmfiles = rm -f $(rm-files)
1753 # Run depmod only if we have System.map and depmod is executable
1754 quiet_cmd_depmod = DEPMOD $(KERNELRELEASE)
1755 cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1758 # Create temporary dir for module support files
1759 # clean it up only when building all modules
1760 cmd_crmodverdir = $(Q)mkdir -p $(MODVERDIR) \
1761 $(if $(KBUILD_MODULES),; rm -f $(MODVERDIR)/*)
1763 # read all saved command lines
1764 cmd_files := $(wildcard .*.cmd)
1766 ifneq ($(cmd_files),)
1767 $(cmd_files): ; # Do not try to update included dependency files
1768 include $(cmd_files)
1771 endif # ifeq ($(config-targets),1)
1772 endif # ifeq ($(mixed-targets),1)
1773 endif # skip-makefile
1778 # Declare the contents of the PHONY variable as phony. We keep that
1779 # information in a variable so we can use it in if_changed and friends.