1 # SPDX-License-Identifier: GPL-2.0
9 # To see a list of typical targets execute "make help"
10 # More info can be located in ./README
11 # Comments in this file are targeted only to the developer, do not
12 # expect to learn how to build the kernel reading this file.
14 # That's our default target when none is given on the command line
18 # We are using a recursive build, so we need to do a little thinking
19 # to get the ordering right.
21 # Most importantly: sub-Makefiles should only ever modify files in
22 # their own directory. If in some directory we have a dependency on
23 # a file in another dir (which doesn't happen often, but it's often
24 # unavoidable when linking the built-in.a targets which finally
25 # turn into vmlinux), we will call a sub make in that other dir, and
26 # after that we are sure that everything which is in that other dir
29 # The only cases where we need to modify files which have global
30 # effects are thus separated out and done before the recursive
31 # descending is started. They are now explicitly listed as the
34 ifneq ($(sub-make-done),1)
36 # Do not use make's built-in rules and variables
37 # (this increases performance and avoids hard-to-debug behaviour)
40 # 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 $(Q) - that's useful
65 # for commands that shall be hidden in non-verbose mode.
69 # If KBUILD_VERBOSE equals 0 then the above command will be hidden.
70 # If KBUILD_VERBOSE equals 1 then the above command is displayed.
72 # To put more focus on warnings, be less verbose as default
73 # Use 'make V=1' to see the full commands
75 ifeq ("$(origin V)", "command line")
82 ifeq ($(KBUILD_VERBOSE),1)
90 # If the user is running make -s (silent mode), suppress echoing of
93 ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
97 export quiet Q KBUILD_VERBOSE
99 # kbuild supports saving output files in a separate directory.
100 # To locate output files in a separate directory two syntaxes are supported.
101 # In both cases the working directory must be the root of the kernel src.
103 # Use "make O=dir/to/store/output/files/"
105 # 2) Set KBUILD_OUTPUT
106 # Set the environment variable KBUILD_OUTPUT to point to the directory
107 # where the output files shall be placed.
108 # export KBUILD_OUTPUT=dir/to/store/output/files/
111 # The O= assignment takes precedence over the KBUILD_OUTPUT environment
114 # KBUILD_SRC is not intended to be used by the regular user (for now),
115 # it is set on invocation of make with KBUILD_OUTPUT or O= specified.
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=$(CURDIR)
147 # Do not print "Entering directory ..." at all for in-tree build.
148 MAKEFLAGS += --no-print-directory
150 endif # ifneq ($(KBUILD_OUTPUT),)
152 PHONY += $(MAKECMDGOALS) sub-make
154 $(filter-out _all sub-make $(CURDIR)/Makefile, $(MAKECMDGOALS)) _all: sub-make
157 # Invoke a second make in the output directory, passing relevant variables
159 $(Q)$(MAKE) sub-make-done=1 \
160 $(if $(KBUILD_OUTPUT),-C $(KBUILD_OUTPUT) KBUILD_SRC=$(CURDIR)) \
161 -f $(CURDIR)/Makefile $(filter-out _all sub-make,$(MAKECMDGOALS))
164 # We process the rest of the Makefile if this is the final invocation of make
166 # Do not print "Entering directory ...",
167 # but we want to display it when entering to the output directory
168 # so that IDEs/editors are able to understand relative filenames.
169 MAKEFLAGS += --no-print-directory
171 # Call a source code checker (by default, "sparse") as part of the
174 # Use 'make C=1' to enable checking of only re-compiled files.
175 # Use 'make C=2' to enable checking of *all* source files, regardless
176 # of whether they are re-compiled or not.
178 # See the file "Documentation/dev-tools/sparse.rst" for more details,
179 # including where to get the "sparse" utility.
181 ifeq ("$(origin C)", "command line")
182 KBUILD_CHECKSRC = $(C)
184 ifndef KBUILD_CHECKSRC
188 # Use make M=dir to specify directory of external module to build
189 # Old syntax make ... SUBDIRS=$PWD is still supported
190 # Setting the environment variable KBUILD_EXTMOD take precedence
192 $(warning ================= WARNING ================)
193 $(warning 'SUBDIRS' will be removed after Linux 5.3)
194 $(warning Please use 'M=' or 'KBUILD_EXTMOD' instead)
195 $(warning ==========================================)
196 KBUILD_EXTMOD ?= $(SUBDIRS)
199 ifeq ("$(origin M)", "command line")
200 KBUILD_EXTMOD := $(M)
203 ifeq ($(KBUILD_SRC),)
204 # building in the source tree
207 ifeq ($(KBUILD_SRC)/,$(dir $(CURDIR)))
208 # building in a subdirectory of the source tree
211 srctree := $(KBUILD_SRC)
215 export KBUILD_CHECKSRC KBUILD_EXTMOD KBUILD_SRC
221 VPATH := $(srctree)$(if $(KBUILD_EXTMOD),:$(KBUILD_EXTMOD))
223 export srctree objtree VPATH
225 # To make sure we do not include .config for any of the *config targets
226 # catch them early, and hand them over to scripts/kconfig/Makefile
227 # It is allowed to specify more targets when calling make, including
228 # mixing *config targets and build targets.
229 # For example 'make oldconfig all'.
230 # Detect when mixed targets is specified, and make a second invocation
231 # of make so .config is not included in this case either (for *config).
233 version_h := include/generated/uapi/linux/version.h
234 old_version_h := include/linux/version.h
236 clean-targets := %clean mrproper cleandocs
237 no-dot-config-targets := $(clean-targets) \
238 cscope gtags TAGS tags help% %docs check% coccicheck \
239 $(version_h) headers_% archheaders archscripts \
240 %asm-generic kernelversion %src-pkg
241 no-sync-config-targets := $(no-dot-config-targets) install %install \
249 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
250 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
255 ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
256 ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
261 ifneq ($(KBUILD_EXTMOD),)
265 ifeq ($(KBUILD_EXTMOD),)
266 ifneq ($(filter config %config,$(MAKECMDGOALS)),)
268 ifneq ($(words $(MAKECMDGOALS)),1)
274 # For "make -j clean all", "make -j mrproper defconfig all", etc.
275 ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
276 ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
281 # install and modules_install need also be processed one by one
282 ifneq ($(filter install,$(MAKECMDGOALS)),)
283 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
288 ifeq ($(mixed-targets),1)
289 # ===========================================================================
290 # We're called with mixed targets (*config and build targets).
291 # Handle them one by one.
293 PHONY += $(MAKECMDGOALS) __build_one_by_one
295 $(filter-out __build_one_by_one, $(MAKECMDGOALS)): __build_one_by_one
300 for i in $(MAKECMDGOALS); do \
301 $(MAKE) -f $(srctree)/Makefile $$i; \
306 # We need some generic definitions (do not try to remake the file).
307 scripts/Kbuild.include: ;
308 include scripts/Kbuild.include
310 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
311 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
312 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
313 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
315 include scripts/subarch.include
317 # Cross compiling and selecting different set of gcc/bin-utils
318 # ---------------------------------------------------------------------------
320 # When performing cross compilation for other architectures ARCH shall be set
321 # to the target architecture. (See arch/* for the possibilities).
322 # ARCH can be set during invocation of make:
324 # Another way is to have ARCH set in the environment.
325 # The default ARCH is the host where make is executed.
327 # CROSS_COMPILE specify the prefix used for all executables used
328 # during compilation. Only gcc and related bin-utils executables
329 # are prefixed with $(CROSS_COMPILE).
330 # CROSS_COMPILE can be set on the command line
331 # make CROSS_COMPILE=ia64-linux-
332 # Alternatively CROSS_COMPILE can be set in the environment.
333 # Default value for CROSS_COMPILE is not to prefix executables
334 # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
337 # Architecture as present in compile.h
338 UTS_MACHINE := $(ARCH)
341 # Additional ARCH settings for x86
345 ifeq ($(ARCH),x86_64)
349 # Additional ARCH settings for sparc
350 ifeq ($(ARCH),sparc32)
353 ifeq ($(ARCH),sparc64)
357 # Additional ARCH settings for sh
362 KCONFIG_CONFIG ?= .config
363 export KCONFIG_CONFIG
365 # SHELL used by kbuild
366 CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
367 else if [ -x /bin/bash ]; then echo /bin/bash; \
368 else echo sh; fi ; fi)
370 HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
371 HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
372 HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
376 KBUILD_HOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 \
377 -fomit-frame-pointer -std=gnu89 $(HOST_LFS_CFLAGS) \
379 KBUILD_HOSTCXXFLAGS := -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
380 KBUILD_HOSTLDFLAGS := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
381 KBUILD_HOSTLDLIBS := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
383 # Make variables (CC, etc...)
384 AS = $(CROSS_COMPILE)as
385 LD = $(CROSS_COMPILE)ld
386 CC = $(CROSS_COMPILE)gcc
388 AR = $(CROSS_COMPILE)ar
389 NM = $(CROSS_COMPILE)nm
390 STRIP = $(CROSS_COMPILE)strip
391 OBJCOPY = $(CROSS_COMPILE)objcopy
392 OBJDUMP = $(CROSS_COMPILE)objdump
396 INSTALLKERNEL := installkernel
397 DEPMOD = /sbin/depmod
404 CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
405 -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
414 # Use USERINCLUDE when you must reference the UAPI directories only.
416 -I$(srctree)/arch/$(SRCARCH)/include/uapi \
417 -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
418 -I$(srctree)/include/uapi \
419 -I$(objtree)/include/generated/uapi \
420 -include $(srctree)/include/linux/kconfig.h
422 # Use LINUXINCLUDE when you must reference the include/ directory.
423 # Needed to be compatible with the O= option
425 -I$(srctree)/arch/$(SRCARCH)/include \
426 -I$(objtree)/arch/$(SRCARCH)/include/generated \
427 $(if $(KBUILD_SRC), -I$(srctree)/include) \
428 -I$(objtree)/include \
431 KBUILD_AFLAGS := -D__ASSEMBLY__ -fno-PIE
432 KBUILD_CFLAGS := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
433 -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
434 -Werror-implicit-function-declaration -Werror=implicit-int \
435 -Wno-format-security \
437 KBUILD_CPPFLAGS := -D__KERNEL__
438 KBUILD_AFLAGS_KERNEL :=
439 KBUILD_CFLAGS_KERNEL :=
440 KBUILD_AFLAGS_MODULE := -DMODULE
441 KBUILD_CFLAGS_MODULE := -DMODULE
442 KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
444 GCC_PLUGINS_CFLAGS :=
446 export ARCH SRCARCH CONFIG_SHELL HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE AS LD CC
447 export CPP AR NM STRIP OBJCOPY OBJDUMP KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS
448 export MAKE LEX YACC AWK INSTALLKERNEL PERL PYTHON PYTHON2 PYTHON3 UTS_MACHINE
449 export HOSTCXX KBUILD_HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
451 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
452 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
453 export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN
454 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
455 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
456 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
457 export KBUILD_ARFLAGS
459 # When compiling out-of-tree modules, put MODVERDIR in the module
460 # tree rather than in the kernel tree. The kernel tree might
462 export MODVERDIR := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_versions
464 # Files to ignore in find ... statements
466 export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o \
467 -name CVS -o -name .pc -o -name .hg -o -name .git \) \
469 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
470 --exclude CVS --exclude .pc --exclude .hg --exclude .git
472 # ===========================================================================
473 # Rules shared between *config targets and build targets
475 # Basic helpers built in scripts/basic/
476 PHONY += scripts_basic
478 $(Q)$(MAKE) $(build)=scripts/basic
479 $(Q)rm -f .tmp_quiet_recordmcount
481 # To avoid any implicit rule to kick in, define an empty command.
482 scripts/basic/%: scripts_basic ;
484 PHONY += outputmakefile
485 # outputmakefile generates a Makefile in the output directory, if using a
486 # separate output directory. This allows convenient use of make in the
488 # At the same time when output Makefile generated, generate .gitignore to
489 # ignore whole output directory
491 ifneq ($(KBUILD_SRC),)
492 $(Q)ln -fsn $(srctree) source
493 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile $(srctree)
494 $(Q){ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
497 ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),)
498 ifneq ($(CROSS_COMPILE),)
499 CLANG_FLAGS := --target=$(notdir $(CROSS_COMPILE:%-=%))
500 GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
501 CLANG_FLAGS += --prefix=$(GCC_TOOLCHAIN_DIR)
502 GCC_TOOLCHAIN := $(realpath $(GCC_TOOLCHAIN_DIR)/..)
504 ifneq ($(GCC_TOOLCHAIN),)
505 CLANG_FLAGS += --gcc-toolchain=$(GCC_TOOLCHAIN)
507 CLANG_FLAGS += -no-integrated-as
508 KBUILD_CFLAGS += $(CLANG_FLAGS)
509 KBUILD_AFLAGS += $(CLANG_FLAGS)
513 RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
514 RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
515 RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
516 RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
517 RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
518 RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
519 export RETPOLINE_CFLAGS
520 export RETPOLINE_VDSO_CFLAGS
522 # The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
523 # Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
524 # CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
525 # and from include/config/auto.conf.cmd to detect the compiler upgrade.
526 CC_VERSION_TEXT = $(shell $(CC) --version | head -n 1)
528 ifeq ($(config-targets),1)
529 # ===========================================================================
530 # *config targets only - make sure prerequisites are updated, and descend
531 # in scripts/kconfig to make the *config target
533 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
534 # KBUILD_DEFCONFIG may point out an alternative default configuration
535 # used for 'make defconfig'
536 include arch/$(SRCARCH)/Makefile
537 export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
539 config: scripts_basic outputmakefile FORCE
540 $(Q)$(MAKE) $(build)=scripts/kconfig $@
542 %config: scripts_basic outputmakefile FORCE
543 $(Q)$(MAKE) $(build)=scripts/kconfig $@
546 # ===========================================================================
547 # Build targets only - this includes vmlinux, arch specific targets, clean
548 # targets and others. In general all targets except *config targets.
550 # If building an external module we do not care about the all: rule
551 # but instead _all depend on modules
553 ifeq ($(KBUILD_EXTMOD),)
559 # Decide whether to build built-in, modular, or both.
560 # Normally, just do built-in.
565 # If we have only "make modules", don't compile built-in objects.
566 # When we're building modules with modversions, we need to consider
567 # the built-in objects during the descend as well, in order to
568 # make sure the checksums are up to date before we record them.
570 ifeq ($(MAKECMDGOALS),modules)
571 KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
574 # If we have "make <whatever> modules", compile modules
575 # in addition to whatever we do anyway.
576 # Just "make" or "make all" shall build modules as well
578 ifneq ($(filter all _all modules,$(MAKECMDGOALS)),)
582 ifeq ($(MAKECMDGOALS),)
586 export KBUILD_MODULES KBUILD_BUILTIN
588 ifeq ($(KBUILD_EXTMOD),)
589 # Objects we will link into vmlinux / subdirs we need to visit
591 drivers-y := drivers/ sound/ firmware/
596 endif # KBUILD_EXTMOD
598 ifeq ($(dot-config),1)
599 include include/config/auto.conf
602 # The all: target is the default when no target is given on the
604 # This allow a user to issue only 'make' to build a kernel including modules
605 # Defaults to vmlinux, but the arch makefile usually adds further targets
608 CFLAGS_GCOV := -fprofile-arcs -ftest-coverage \
609 $(call cc-option,-fno-tree-loop-im) \
610 $(call cc-disable-warning,maybe-uninitialized,)
613 # The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
614 ifdef CONFIG_FUNCTION_TRACER
615 CC_FLAGS_FTRACE := -pg
618 # The arch Makefile can set ARCH_{CPP,A,C}FLAGS to override the default
619 # values of the respective KBUILD_* variables
623 include arch/$(SRCARCH)/Makefile
625 ifeq ($(dot-config),1)
626 ifeq ($(may-sync-config),1)
627 # Read in dependencies to all Kconfig* files, make sure to run syncconfig if
628 # changes are detected. This should be included after arch/$(SRCARCH)/Makefile
629 # because some architectures define CROSS_COMPILE there.
630 -include include/config/auto.conf.cmd
632 # To avoid any implicit rule to kick in, define an empty command
633 $(KCONFIG_CONFIG) include/config/auto.conf.cmd: ;
635 # The actual configuration files used during the build are stored in
636 # include/generated/ and include/config/. Update them if .config is newer than
637 # include/config/auto.conf (which mirrors .config).
638 include/config/%.conf: $(KCONFIG_CONFIG) include/config/auto.conf.cmd
639 $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
641 # External modules and some install targets need include/generated/autoconf.h
642 # and include/config/auto.conf but do not care if they are up-to-date.
643 # Use auto.conf to trigger the test
644 PHONY += include/config/auto.conf
646 include/config/auto.conf:
647 $(Q)test -e include/generated/autoconf.h -a -e $@ || ( \
649 echo >&2 " ERROR: Kernel configuration is invalid."; \
650 echo >&2 " include/generated/autoconf.h or $@ are missing.";\
651 echo >&2 " Run 'make oldconfig && make prepare' on kernel src to fix it."; \
655 endif # may-sync-config
656 endif # $(dot-config)
658 KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,)
659 KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,)
660 KBUILD_CFLAGS += $(call cc-disable-warning, format-truncation)
661 KBUILD_CFLAGS += $(call cc-disable-warning, format-overflow)
662 KBUILD_CFLAGS += $(call cc-disable-warning, int-in-bool-context)
664 ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
665 KBUILD_CFLAGS += $(call cc-option,-Oz,-Os)
670 ifdef CONFIG_CC_DISABLE_WARN_MAYBE_UNINITIALIZED
671 KBUILD_CFLAGS += -Wno-maybe-uninitialized
674 # Tell gcc to never replace conditional load with a non-conditional one
675 KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
677 include scripts/Makefile.kcov
678 include scripts/Makefile.gcc-plugins
680 ifdef CONFIG_READABLE_ASM
681 # Disable optimizations that make assembler listings hard to read.
682 # reorder blocks reorders the control in the function
683 # ipa clone creates specialized cloned functions
684 # partial inlining inlines only parts of functions
685 KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
686 $(call cc-option,-fno-ipa-cp-clone,) \
687 $(call cc-option,-fno-partial-inlining)
690 ifneq ($(CONFIG_FRAME_WARN),0)
691 KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
694 stackp-flags-$(CONFIG_CC_HAS_STACKPROTECTOR_NONE) := -fno-stack-protector
695 stackp-flags-$(CONFIG_STACKPROTECTOR) := -fstack-protector
696 stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG) := -fstack-protector-strong
698 KBUILD_CFLAGS += $(stackp-flags-y)
700 ifdef CONFIG_CC_IS_CLANG
701 KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
702 KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier)
703 KBUILD_CFLAGS += $(call cc-disable-warning, gnu)
704 KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
705 # Quiet clang warning: comparison of unsigned expression < 0 is always false
706 KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare)
707 # CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
708 # source of a reference will be _MergedGlobals and not on of the whitelisted names.
709 # See modpost pattern 2
710 KBUILD_CFLAGS += $(call cc-option, -mno-global-merge,)
711 KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior)
714 # These warnings generated too much noise in a regular build.
715 # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
716 KBUILD_CFLAGS += -Wno-unused-but-set-variable
719 KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
720 ifdef CONFIG_FRAME_POINTER
721 KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
723 # Some targets (ARM with Thumb2, for example), can't be built with frame
724 # pointers. For those, we don't have FUNCTION_TRACER automatically
725 # select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
726 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
727 # -fomit-frame-pointer with FUNCTION_TRACER.
728 ifndef CONFIG_FUNCTION_TRACER
729 KBUILD_CFLAGS += -fomit-frame-pointer
733 DEBUG_CFLAGS := $(call cc-option, -fno-var-tracking-assignments)
735 ifdef CONFIG_DEBUG_INFO
736 ifdef CONFIG_DEBUG_INFO_SPLIT
737 DEBUG_CFLAGS += $(call cc-option, -gsplit-dwarf, -g)
741 KBUILD_AFLAGS += -Wa,-gdwarf-2
743 ifdef CONFIG_DEBUG_INFO_DWARF4
744 DEBUG_CFLAGS += $(call cc-option, -gdwarf-4,)
747 ifdef CONFIG_DEBUG_INFO_REDUCED
748 DEBUG_CFLAGS += $(call cc-option, -femit-struct-debug-baseonly) \
749 $(call cc-option,-fno-var-tracking)
752 KBUILD_CFLAGS += $(DEBUG_CFLAGS)
755 ifdef CONFIG_FUNCTION_TRACER
756 ifdef CONFIG_FTRACE_MCOUNT_RECORD
757 # gcc 5 supports generating the mcount tables directly
758 ifeq ($(call cc-option-yn,-mrecord-mcount),y)
759 CC_FLAGS_FTRACE += -mrecord-mcount
760 export CC_USING_RECORD_MCOUNT := 1
762 ifdef CONFIG_HAVE_NOP_MCOUNT
763 ifeq ($(call cc-option-yn, -mnop-mcount),y)
764 CC_FLAGS_FTRACE += -mnop-mcount
765 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
769 ifdef CONFIG_HAVE_FENTRY
770 ifeq ($(call cc-option-yn, -mfentry),y)
771 CC_FLAGS_FTRACE += -mfentry
772 CC_FLAGS_USING += -DCC_USING_FENTRY
775 export CC_FLAGS_FTRACE
776 KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
777 KBUILD_AFLAGS += $(CC_FLAGS_USING)
778 ifdef CONFIG_DYNAMIC_FTRACE
779 ifdef CONFIG_HAVE_C_RECORDMCOUNT
780 BUILD_C_RECORDMCOUNT := y
781 export BUILD_C_RECORDMCOUNT
786 # We trigger additional mismatches with less inlining
787 ifdef CONFIG_DEBUG_SECTION_MISMATCH
788 KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
791 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
792 KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
793 LDFLAGS_vmlinux += --gc-sections
796 # arch Makefile may override CC so keep this after arch Makefile is included
797 NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
799 # warn about C99 declaration after statement
800 KBUILD_CFLAGS += -Wdeclaration-after-statement
802 # Variable Length Arrays (VLAs) should not be used anywhere in the kernel
803 KBUILD_CFLAGS += $(call cc-option,-Wvla)
805 # disable pointer signed / unsigned warnings in gcc 4.0
806 KBUILD_CFLAGS += -Wno-pointer-sign
808 # disable stringop warnings in gcc 8+
809 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
811 # disable invalid "can't wrap" optimizations for signed / pointers
812 KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow)
814 # clang sets -fmerge-all-constants by default as optimization, but this
815 # is non-conforming behavior for C and in fact breaks the kernel, so we
816 # need to disable it here generally.
817 KBUILD_CFLAGS += $(call cc-option,-fno-merge-all-constants)
819 # for gcc -fno-merge-all-constants disables everything, but it is fine
820 # to have actual conforming behavior enabled.
821 KBUILD_CFLAGS += $(call cc-option,-fmerge-constants)
823 # Make sure -fstack-check isn't enabled (like gentoo apparently did)
824 KBUILD_CFLAGS += $(call cc-option,-fno-stack-check,)
826 # conserve stack if available
827 KBUILD_CFLAGS += $(call cc-option,-fconserve-stack)
829 # Prohibit date/time macros, which would make the build non-deterministic
830 KBUILD_CFLAGS += $(call cc-option,-Werror=date-time)
832 # enforce correct pointer usage
833 KBUILD_CFLAGS += $(call cc-option,-Werror=incompatible-pointer-types)
835 # Require designated initializers for all marked structures
836 KBUILD_CFLAGS += $(call cc-option,-Werror=designated-init)
838 # change __FILE__ to the relative path from the srctree
839 KBUILD_CFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
841 # use the deterministic mode of AR if available
842 KBUILD_ARFLAGS := $(call ar-option,D)
844 include scripts/Makefile.kasan
845 include scripts/Makefile.extrawarn
846 include scripts/Makefile.ubsan
848 # Add any arch overrides and user supplied CPPFLAGS, AFLAGS and CFLAGS as the
850 KBUILD_CPPFLAGS += $(ARCH_CPPFLAGS) $(KCPPFLAGS)
851 KBUILD_AFLAGS += $(ARCH_AFLAGS) $(KAFLAGS)
852 KBUILD_CFLAGS += $(ARCH_CFLAGS) $(KCFLAGS)
854 # Use --build-id when available.
855 LDFLAGS_BUILD_ID := $(call ld-option, --build-id)
856 KBUILD_LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID)
857 LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)
859 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
860 LDFLAGS_vmlinux += $(call ld-option, -X,)
863 # insure the checker run with the right endianness
864 CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
866 # the checker needs the correct machine size
867 CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
869 # Default kernel image to build when no specific target is given.
870 # KBUILD_IMAGE may be overruled on the command line or
871 # set in the environment
872 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
874 export KBUILD_IMAGE ?= vmlinux
877 # INSTALL_PATH specifies where to place the updated kernel and system map
878 # images. Default is /boot, but you can set it to other values
879 export INSTALL_PATH ?= /boot
882 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
883 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
884 # an argument if needed. Otherwise it defaults to the kernel install path
886 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
889 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
890 # relocations required by build roots. This is not defined in the
891 # makefile but the argument can be passed to make if needed.
894 MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
898 # INSTALL_MOD_STRIP, if defined, will cause modules to be
899 # stripped after they are installed. If INSTALL_MOD_STRIP is '1', then
900 # the default option --strip-debug will be used. Otherwise,
901 # INSTALL_MOD_STRIP value will be used as the options to the strip command.
903 ifdef INSTALL_MOD_STRIP
904 ifeq ($(INSTALL_MOD_STRIP),1)
905 mod_strip_cmd = $(STRIP) --strip-debug
907 mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
908 endif # INSTALL_MOD_STRIP=1
911 endif # INSTALL_MOD_STRIP
914 # CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
915 # after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
916 # or CONFIG_MODULE_COMPRESS_XZ.
918 mod_compress_cmd = true
919 ifdef CONFIG_MODULE_COMPRESS
920 ifdef CONFIG_MODULE_COMPRESS_GZIP
921 mod_compress_cmd = gzip -n -f
922 endif # CONFIG_MODULE_COMPRESS_GZIP
923 ifdef CONFIG_MODULE_COMPRESS_XZ
924 mod_compress_cmd = xz -f
925 endif # CONFIG_MODULE_COMPRESS_XZ
926 endif # CONFIG_MODULE_COMPRESS
927 export mod_compress_cmd
929 # Select initial ramdisk compression format, default is gzip(1).
930 # This shall be used by the dracut(8) tool while creating an initramfs image.
932 INITRD_COMPRESS-y := gzip
933 INITRD_COMPRESS-$(CONFIG_RD_BZIP2) := bzip2
934 INITRD_COMPRESS-$(CONFIG_RD_LZMA) := lzma
935 INITRD_COMPRESS-$(CONFIG_RD_XZ) := xz
936 INITRD_COMPRESS-$(CONFIG_RD_LZO) := lzo
937 INITRD_COMPRESS-$(CONFIG_RD_LZ4) := lz4
938 # do not export INITRD_COMPRESS, since we didn't actually
939 # choose a sane default compression above.
940 # export INITRD_COMPRESS := $(INITRD_COMPRESS-y)
942 ifdef CONFIG_MODULE_SIG_ALL
943 $(eval $(call config_filename,MODULE_SIG_KEY))
945 mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
951 ifdef CONFIG_STACK_VALIDATION
952 has_libelf := $(call try-run,\
953 echo "int main() {}" | $(HOSTCC) -xc -o /dev/null -lelf -,1,0)
954 ifeq ($(has_libelf),1)
955 objtool_target := tools/objtool FORCE
957 SKIP_STACK_VALIDATION := 1
958 export SKIP_STACK_VALIDATION
964 ifeq ($(KBUILD_EXTMOD),)
965 core-y += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
967 vmlinux-dirs := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
968 $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
969 $(net-y) $(net-m) $(libs-y) $(libs-m) $(virt-y)))
971 vmlinux-alldirs := $(sort $(vmlinux-dirs) $(patsubst %/,%,$(filter %/, \
972 $(init-) $(core-) $(drivers-) $(net-) $(libs-) $(virt-))))
974 init-y := $(patsubst %/, %/built-in.a, $(init-y))
975 core-y := $(patsubst %/, %/built-in.a, $(core-y))
976 drivers-y := $(patsubst %/, %/built-in.a, $(drivers-y))
977 net-y := $(patsubst %/, %/built-in.a, $(net-y))
978 libs-y1 := $(patsubst %/, %/lib.a, $(libs-y))
979 libs-y2 := $(patsubst %/, %/built-in.a, $(filter-out %.a, $(libs-y)))
980 virt-y := $(patsubst %/, %/built-in.a, $(virt-y))
982 # Externally visible symbols (used by link-vmlinux.sh)
983 export KBUILD_VMLINUX_OBJS := $(head-y) $(init-y) $(core-y) $(libs-y2) \
984 $(drivers-y) $(net-y) $(virt-y)
985 export KBUILD_VMLINUX_LIBS := $(libs-y1)
986 export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
987 export LDFLAGS_vmlinux
988 # used by scripts/package/Makefile
989 export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) arch Documentation include samples scripts tools)
991 vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
993 # Recurse until adjust_autoksyms.sh is satisfied
994 PHONY += autoksyms_recursive
995 autoksyms_recursive: $(vmlinux-deps)
996 ifdef CONFIG_TRIM_UNUSED_KSYMS
997 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
998 "$(MAKE) -f $(srctree)/Makefile vmlinux"
1001 # For the kernel to actually contain only the needed exported symbols,
1002 # we have to build modules as well to determine what those symbols are.
1003 # (this can be evaluated only once include/config/auto.conf has been included)
1004 ifdef CONFIG_TRIM_UNUSED_KSYMS
1008 autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1011 $(Q)mkdir -p $(dir $@)
1014 ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1016 # Final link of vmlinux with optional arch pass after final link
1017 cmd_link-vmlinux = \
1018 $(CONFIG_SHELL) $< $(LD) $(KBUILD_LDFLAGS) $(LDFLAGS_vmlinux) ; \
1019 $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1021 vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1022 +$(call if_changed,link-vmlinux)
1026 # Build samples along the rest of the kernel. This needs headers_install.
1027 ifdef CONFIG_SAMPLES
1028 vmlinux-dirs += samples
1029 samples: headers_install
1032 # The actual objects are generated when descending,
1033 # make sure no implicit rule kicks in
1034 $(sort $(vmlinux-deps)): $(vmlinux-dirs) ;
1036 # Handle descending into subdirectories listed in $(vmlinux-dirs)
1037 # Preset locale variables to speed up the build process. Limit locale
1038 # tweaks to this spot to avoid wrong language settings when running
1039 # make menuconfig etc.
1040 # Error messages still appears in the original language
1042 PHONY += $(vmlinux-dirs)
1043 $(vmlinux-dirs): prepare
1044 $(Q)$(MAKE) $(build)=$@ need-builtin=1
1046 filechk_kernel.release = \
1047 echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1049 # Store (new) KERNELRELEASE string in include/config/kernel.release
1050 include/config/kernel.release: $(srctree)/Makefile FORCE
1051 $(call filechk,kernel.release)
1053 # Additional helpers built in scripts/
1054 # Carefully list dependencies so we do not try to build scripts twice
1057 scripts: scripts_basic scripts_dtc
1058 $(Q)$(MAKE) $(build)=$(@)
1060 # Things we need to do before we recursively start building the kernel
1061 # or the modules are listed in "prepare".
1062 # A multi level approach is used. prepareN is processed before prepareN-1.
1063 # archprepare is used in arch Makefiles and when processed asm symlink,
1064 # version.h and scripts_basic is processed / created.
1066 PHONY += prepare archprepare prepare1 prepare3
1068 # prepare3 is used to check if we are building in a separate output directory,
1070 # 1) Check that make has not been executed in the kernel src $(srctree)
1071 prepare3: include/config/kernel.release
1072 ifneq ($(KBUILD_SRC),)
1073 @$(kecho) ' Using $(srctree) as source for kernel'
1074 $(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \
1075 echo >&2 " $(srctree) is not clean, please run 'make mrproper'"; \
1076 echo >&2 " in the '$(srctree)' directory.";\
1081 prepare1: prepare3 outputmakefile asm-generic $(version_h) $(autoksyms_h) \
1082 include/generated/utsrelease.h
1085 archprepare: archheaders archscripts prepare1 scripts
1087 prepare0: archprepare
1088 $(Q)$(MAKE) $(build)=scripts/mod
1089 $(Q)$(MAKE) $(build)=.
1091 # All the preparing..
1092 prepare: prepare0 prepare-objtool
1094 # Support for using generic headers in asm-generic
1095 asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1097 PHONY += asm-generic uapi-asm-generic
1098 asm-generic: uapi-asm-generic
1099 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm
1101 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm
1103 PHONY += prepare-objtool
1104 prepare-objtool: $(objtool_target)
1105 ifeq ($(SKIP_STACK_VALIDATION),1)
1106 ifdef CONFIG_UNWINDER_ORC
1107 @echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1110 @echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1114 # Generate some files
1115 # ---------------------------------------------------------------------------
1117 # KERNELRELEASE can change from a few different places, meaning version.h
1118 # needs to be updated, so this check is forced on all builds
1121 define filechk_utsrelease.h
1122 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1123 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1126 echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1129 define filechk_version.h
1130 echo \#define LINUX_VERSION_CODE $(shell \
1131 expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1132 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))'
1136 $(call filechk,version.h)
1137 $(Q)rm -f $(old_version_h)
1139 include/generated/utsrelease.h: include/config/kernel.release FORCE
1140 $(call filechk,utsrelease.h)
1144 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1145 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1147 # ---------------------------------------------------------------------------
1150 #Default location for installed headers
1151 export INSTALL_HDR_PATH = $(objtree)/usr
1153 # If we do an all arch process set dst to include/arch-$(SRCARCH)
1154 hdr-dst = $(if $(KBUILD_HEADERS), dst=include/arch-$(SRCARCH), dst=include)
1156 PHONY += archheaders archscripts
1159 __headers: $(version_h) scripts_basic uapi-asm-generic archheaders archscripts
1160 $(Q)$(MAKE) $(build)=scripts build_unifdef
1162 PHONY += headers_install_all
1163 headers_install_all:
1164 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh install
1166 PHONY += headers_install
1167 headers_install: __headers
1168 $(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1169 $(error Headers not exportable for the $(SRCARCH) architecture))
1170 $(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include
1171 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi $(hdr-dst)
1173 PHONY += headers_check_all
1174 headers_check_all: headers_install_all
1175 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh check
1177 PHONY += headers_check
1178 headers_check: headers_install
1179 $(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include HDRCHECK=1
1180 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi $(hdr-dst) HDRCHECK=1
1182 ifdef CONFIG_HEADERS_CHECK
1186 # ---------------------------------------------------------------------------
1191 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1193 PHONY += kselftest-clean
1195 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests clean
1197 PHONY += kselftest-merge
1199 $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1200 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/kconfig/merge_config.sh \
1201 -m $(objtree)/.config \
1202 $(srctree)/tools/testing/selftests/*/config
1203 +$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1205 # ---------------------------------------------------------------------------
1208 ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1209 dtstree := arch/$(SRCARCH)/boot/dts
1214 %.dtb: prepare3 scripts_dtc
1215 $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1217 PHONY += dtbs dtbs_install dt_binding_check
1218 dtbs dtbs_check: prepare3 scripts_dtc
1219 $(Q)$(MAKE) $(build)=$(dtstree)
1221 dtbs_check: export CHECK_DTBS=1
1222 dtbs_check: dt_binding_check
1225 $(Q)$(MAKE) $(dtbinst)=$(dtstree)
1227 ifdef CONFIG_OF_EARLY_FLATTREE
1233 PHONY += scripts_dtc
1234 scripts_dtc: scripts_basic
1235 $(Q)$(MAKE) $(build)=scripts/dtc
1237 dt_binding_check: scripts_dtc
1238 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1240 # ---------------------------------------------------------------------------
1243 ifdef CONFIG_MODULES
1245 # By default, build modules as well
1251 # A module can be listed more than once in obj-m resulting in
1252 # duplicate lines in modules.order files. Those are removed
1253 # using awk while concatenating to the final file.
1256 modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux) modules.builtin
1257 $(Q)$(AWK) '!x[$$0]++' $(vmlinux-dirs:%=$(objtree)/%/modules.order) > $(objtree)/modules.order
1258 @$(kecho) ' Building modules, stage 2.';
1259 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1261 modules.builtin: $(vmlinux-dirs:%=%/modules.builtin)
1262 $(Q)$(AWK) '!x[$$0]++' $^ > $(objtree)/modules.builtin
1264 %/modules.builtin: include/config/auto.conf include/config/tristate.conf
1265 $(Q)$(MAKE) $(modbuiltin)=$*
1268 # Target to prepare building external modules
1269 PHONY += modules_prepare
1270 modules_prepare: prepare
1272 # Target to install modules
1273 PHONY += modules_install
1274 modules_install: _modinst_ _modinst_post
1278 @rm -rf $(MODLIB)/kernel
1279 @rm -f $(MODLIB)/source
1280 @mkdir -p $(MODLIB)/kernel
1281 @ln -s $(abspath $(srctree)) $(MODLIB)/source
1282 @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
1283 rm -f $(MODLIB)/build ; \
1284 ln -s $(CURDIR) $(MODLIB)/build ; \
1286 @cp -f $(objtree)/modules.order $(MODLIB)/
1287 @cp -f $(objtree)/modules.builtin $(MODLIB)/
1288 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1290 # This depmod is only for convenience to give the initial
1291 # boot a modules.dep even before / is mounted read-write. However the
1292 # boot script depmod is the master version.
1293 PHONY += _modinst_post
1294 _modinst_post: _modinst_
1297 ifeq ($(CONFIG_MODULE_SIG), y)
1298 PHONY += modules_sign
1300 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1303 else # CONFIG_MODULES
1305 # Modules not configured
1306 # ---------------------------------------------------------------------------
1308 PHONY += modules modules_install
1309 modules modules_install:
1311 @echo >&2 "The present kernel configuration has modules disabled."
1312 @echo >&2 "Type 'make config' and enable loadable module support."
1313 @echo >&2 "Then build a kernel with module support enabled."
1317 endif # CONFIG_MODULES
1320 # Cleaning is done on three levels.
1321 # make clean Delete most generated files
1322 # Leave enough to build external modules
1323 # make mrproper Delete the current configuration, and all generated files
1324 # make distclean Remove editor backup files, patch leftover files and the like
1326 # Directories & files removed with 'make clean'
1327 CLEAN_DIRS += $(MODVERDIR) include/ksym
1329 # Directories & files removed with 'make mrproper'
1330 MRPROPER_DIRS += include/config usr/include include/generated \
1331 arch/*/include/generated .tmp_objdiff
1332 MRPROPER_FILES += .config .config.old .version \
1333 Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS \
1334 signing_key.pem signing_key.priv signing_key.x509 \
1335 x509.genkey extra_certificates signing_key.x509.keyid \
1336 signing_key.x509.signer vmlinux-gdb.py
1338 # clean - Delete most, but leave enough to build external modules
1340 clean: rm-dirs := $(CLEAN_DIRS)
1341 clean: rm-files := $(CLEAN_FILES)
1342 clean-dirs := $(addprefix _clean_, . $(vmlinux-alldirs) Documentation samples)
1344 PHONY += $(clean-dirs) clean archclean vmlinuxclean
1346 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1349 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1350 $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1352 clean: archclean vmlinuxclean
1354 # mrproper - Delete all generated files, including .config
1356 mrproper: rm-dirs := $(wildcard $(MRPROPER_DIRS))
1357 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1358 mrproper-dirs := $(addprefix _mrproper_,scripts)
1360 PHONY += $(mrproper-dirs) mrproper
1362 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1364 mrproper: clean $(mrproper-dirs)
1373 @find $(srctree) $(RCS_FIND_IGNORE) \
1374 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1375 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1376 -o -name 'core' \) \
1377 -type f -print | xargs rm -f
1380 # Packaging of the kernel to various formats
1381 # ---------------------------------------------------------------------------
1382 package-dir := scripts/package
1385 $(Q)$(MAKE) $(build)=$(package-dir) $@
1386 %pkg: include/config/kernel.release FORCE
1387 $(Q)$(MAKE) $(build)=$(package-dir) $@
1390 # Brief documentation of the typical targets used
1391 # ---------------------------------------------------------------------------
1393 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1394 boards := $(sort $(notdir $(boards)))
1395 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1396 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1400 @echo 'Cleaning targets:'
1401 @echo ' clean - Remove most generated files but keep the config and'
1402 @echo ' enough build support to build external modules'
1403 @echo ' mrproper - Remove all generated files + config + various backup files'
1404 @echo ' distclean - mrproper + remove editor backup and patch files'
1406 @echo 'Configuration targets:'
1407 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1409 @echo 'Other generic targets:'
1410 @echo ' all - Build all targets marked with [*]'
1411 @echo '* vmlinux - Build the bare kernel'
1412 @echo '* modules - Build all modules'
1413 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1414 @echo ' dir/ - Build all files in dir and below'
1415 @echo ' dir/file.[ois] - Build specified target only'
1416 @echo ' dir/file.ll - Build the LLVM assembly file'
1417 @echo ' (requires compiler support for LLVM assembly generation)'
1418 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1419 @echo ' (requires a recent binutils and recent build (System.map))'
1420 @echo ' dir/file.ko - Build module including final link'
1421 @echo ' modules_prepare - Set up for building external modules'
1422 @echo ' tags/TAGS - Generate tags file for editors'
1423 @echo ' cscope - Generate cscope index'
1424 @echo ' gtags - Generate GNU GLOBAL index'
1425 @echo ' kernelrelease - Output the release version string (use with make -s)'
1426 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1427 @echo ' image_name - Output the image name (use with make -s)'
1428 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1429 echo ' (default: $(INSTALL_HDR_PATH))'; \
1431 @echo 'Static analysers:'
1432 @echo ' checkstack - Generate a list of stack hogs'
1433 @echo ' namespacecheck - Name space analysis on compiled kernel'
1434 @echo ' versioncheck - Sanity check on version.h usage'
1435 @echo ' includecheck - Check for duplicate included header files'
1436 @echo ' export_report - List the usages of all exported symbols'
1437 @echo ' headers_check - Sanity check on exported headers'
1438 @echo ' headerdep - Detect inclusion cycles in headers'
1439 @echo ' coccicheck - Check with Coccinelle'
1441 @echo 'Kernel selftest:'
1442 @echo ' kselftest - Build and run kernel selftest (run as root)'
1443 @echo ' Build, install, and boot kernel before'
1444 @echo ' running kselftest on it'
1445 @echo ' kselftest-clean - Remove all generated kselftest files'
1446 @echo ' kselftest-merge - Merge all the config dependencies of kselftest to existing'
1450 echo 'Devicetree:'; \
1451 echo '* dtbs - Build device tree blobs for enabled boards'; \
1452 echo ' dtbs_install - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1455 @echo 'Userspace tools targets:'
1456 @echo ' use "make tools/help"'
1457 @echo ' or "cd tools; make help"'
1459 @echo 'Kernel packaging:'
1460 @$(MAKE) $(build)=$(package-dir) help
1462 @echo 'Documentation targets:'
1463 @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1465 @echo 'Architecture specific targets ($(SRCARCH)):'
1466 @$(if $(archhelp),$(archhelp),\
1467 echo ' No architecture specific help defined for $(SRCARCH)')
1470 $(foreach b, $(boards), \
1471 printf " %-24s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1473 @$(if $(board-dirs), \
1474 $(foreach b, $(board-dirs), \
1475 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1476 printf " %-16s - Show all of the above\\n" help-boards; \
1479 @echo ' make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1480 @echo ' make V=2 [targets] 2 => give reason for rebuild of target'
1481 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1482 @echo ' make C=1 [targets] Check re-compiled c source with $$CHECK (sparse by default)'
1483 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1484 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1485 @echo ' make W=n [targets] Enable extra gcc checks, n=1,2,3 where'
1486 @echo ' 1: warnings which may be relevant and do not occur too often'
1487 @echo ' 2: warnings which occur quite often but may still be relevant'
1488 @echo ' 3: more obscure warnings, can most likely be ignored'
1489 @echo ' Multiple levels can be combined with W=12 or W=123'
1491 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1492 @echo 'For further info see the ./README file'
1495 help-board-dirs := $(addprefix help-,$(board-dirs))
1497 help-boards: $(help-board-dirs)
1499 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1501 $(help-board-dirs): help-%:
1502 @echo 'Architecture specific targets ($(SRCARCH) $*):'
1503 @$(if $(boards-per-dir), \
1504 $(foreach b, $(boards-per-dir), \
1505 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1509 # Documentation targets
1510 # ---------------------------------------------------------------------------
1511 DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1512 linkcheckdocs dochelp refcheckdocs
1513 PHONY += $(DOC_TARGETS)
1514 $(DOC_TARGETS): scripts_basic FORCE
1515 $(Q)$(MAKE) $(build)=Documentation $@
1518 # ---------------------------------------------------------------------------
1520 PHONY += scripts_gdb
1521 scripts_gdb: prepare
1522 $(Q)$(MAKE) $(build)=scripts/gdb
1523 $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1525 ifdef CONFIG_GDB_SCRIPTS
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
1551 PHONY += $(objtree)/Module.symvers
1552 $(objtree)/Module.symvers:
1553 @test -e $(objtree)/Module.symvers || ( \
1555 echo " WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1556 echo " is missing; modules will have no dependencies and modversions."; \
1559 module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
1560 PHONY += $(module-dirs) modules
1561 $(module-dirs): prepare $(objtree)/Module.symvers
1562 $(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@)
1564 modules: $(module-dirs)
1565 @$(kecho) ' Building modules, stage 2.';
1566 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1568 PHONY += modules_install
1569 modules_install: _emodinst_ _emodinst_post
1571 install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1574 $(Q)mkdir -p $(MODLIB)/$(install-dir)
1575 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1577 PHONY += _emodinst_post
1578 _emodinst_post: _emodinst_
1581 clean-dirs := $(addprefix _clean_,$(KBUILD_EXTMOD))
1583 PHONY += $(clean-dirs) clean
1585 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1587 clean: rm-dirs := $(MODVERDIR)
1588 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers
1592 @echo ' Building external modules.'
1593 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1595 @echo ' modules - default target, build the module(s)'
1596 @echo ' modules_install - install the module'
1597 @echo ' clean - remove generated files in module directory only'
1603 endif # KBUILD_EXTMOD
1605 clean: $(clean-dirs)
1608 @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1609 \( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1611 -o -name '*.dtb' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1612 -o -name '*.dwo' -o -name '*.lst' \
1614 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1615 -o -name '*.lex.c' -o -name '*.tab.[ch]' \
1616 -o -name '*.asn1.[ch]' \
1617 -o -name '*.symtypes' -o -name 'modules.order' \
1618 -o -name modules.builtin -o -name '.tmp_*.o.*' \
1619 -o -name '*.c.[012]*.*' \
1621 -o -name '*.gcno' \) -type f -print | xargs rm -f
1623 # Generate tags for editors
1624 # ---------------------------------------------------------------------------
1625 quiet_cmd_tags = GEN $@
1626 cmd_tags = $(CONFIG_SHELL) $(srctree)/scripts/tags.sh $@
1628 tags TAGS cscope gtags: FORCE
1631 # Scripts to check various things for consistency
1632 # ---------------------------------------------------------------------------
1634 PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1637 find $(srctree)/* $(RCS_FIND_IGNORE) \
1638 -name '*.[hcS]' -type f -print | sort \
1639 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1642 find $(srctree)/* $(RCS_FIND_IGNORE) \
1643 -name '*.[hcS]' -type f -print | sort \
1644 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1647 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/$@
1650 $(PERL) $(srctree)/scripts/namespace.pl
1653 $(PERL) $(srctree)/scripts/export_report.pl
1655 PHONY += checkstack kernelrelease kernelversion image_name
1657 # UML needs a little special treatment here. It wants to use the host
1658 # toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
1659 # else wants $(ARCH), including people doing cross-builds, which means
1660 # that $(SUBARCH) doesn't work here.
1662 CHECKSTACK_ARCH := $(SUBARCH)
1664 CHECKSTACK_ARCH := $(ARCH)
1667 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1668 $(PERL) $(src)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1671 @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1674 @echo $(KERNELVERSION)
1677 @echo $(KBUILD_IMAGE)
1679 # Clear a bunch of variables before executing the submake
1681 ifeq ($(quiet),silent_)
1686 $(Q)mkdir -p $(objtree)/tools
1687 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(src)/tools/
1690 $(Q)mkdir -p $(objtree)/tools
1691 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(src)/tools/ $*
1694 # ---------------------------------------------------------------------------
1695 # Single targets are compatible with:
1696 # - build with mixed source and output
1697 # - build with separate output dir 'make O=...'
1698 # - external modules
1700 # target-dir => where to store outputfile
1701 # build-dir => directory in kernel source tree to use
1703 ifeq ($(KBUILD_EXTMOD),)
1704 build-dir = $(patsubst %/,%,$(dir $@))
1705 target-dir = $(dir $@)
1707 zap-slash=$(filter-out .,$(patsubst %/,%,$(dir $@)))
1708 build-dir = $(KBUILD_EXTMOD)$(if $(zap-slash),/$(zap-slash))
1709 target-dir = $(if $(KBUILD_EXTMOD),$(dir $<),$(dir $@))
1712 %.s: %.c prepare FORCE
1713 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1714 %.i: %.c prepare FORCE
1715 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1716 %.o: %.c prepare FORCE
1717 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1718 %.lst: %.c prepare FORCE
1719 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1720 %.s: %.S prepare FORCE
1721 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1722 %.o: %.S prepare FORCE
1723 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1724 %.symtypes: %.c prepare FORCE
1725 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1726 %.ll: %.c prepare FORCE
1727 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1733 # Make sure the latest headers are built for Documentation
1734 Documentation/ samples/: headers_install
1736 $(Q)$(MAKE) KBUILD_MODULES=1 $(build)=$(build-dir)
1738 $(Q)$(MAKE) $(build)=$(build-dir) $(@:.ko=.o)
1739 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1741 # FIXME Should go into a make.lib or something
1742 # ===========================================================================
1744 quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN $(wildcard $(rm-dirs)))
1745 cmd_rmdirs = rm -rf $(rm-dirs)
1747 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
1748 cmd_rmfiles = rm -f $(rm-files)
1750 # Run depmod only if we have System.map and depmod is executable
1751 quiet_cmd_depmod = DEPMOD $(KERNELRELEASE)
1752 cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1755 # Create temporary dir for module support files
1756 # clean it up only when building all modules
1757 cmd_crmodverdir = $(Q)mkdir -p $(MODVERDIR) \
1758 $(if $(KBUILD_MODULES),; rm -f $(MODVERDIR)/*)
1760 # read saved command lines for existing targets
1761 existing-targets := $(wildcard $(sort $(targets)))
1763 cmd_files := $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
1764 $(cmd_files): ; # Do not try to update included dependency files
1765 -include $(cmd_files)
1767 endif # ifeq ($(config-targets),1)
1768 endif # ifeq ($(mixed-targets),1)
1769 endif # sub-make-done
1774 # Declare the contents of the PHONY variable as phony. We keep that
1775 # information in a variable so we can use it in if_changed and friends.