8 # To see a list of typical targets execute "make help"
9 # More info can be located in ./README
10 # Comments in this file are targeted only to the developer, do not
11 # expect to learn how to build the kernel reading this file.
13 # o Do not use make's built-in rules and variables
14 # (this increases performance and avoids hard-to-debug behaviour);
15 # o Look for make include files relative to root of kernel src
16 MAKEFLAGS += -rR --include-dir=$(CURDIR)
18 # Avoid funny character set dependencies
22 export LC_COLLATE LC_NUMERIC
24 # Avoid interference with shell env settings
27 # We are using a recursive build, so we need to do a little thinking
28 # to get the ordering right.
30 # Most importantly: sub-Makefiles should only ever modify files in
31 # their own directory. If in some directory we have a dependency on
32 # a file in another dir (which doesn't happen often, but it's often
33 # unavoidable when linking the built-in.o targets which finally
34 # turn into vmlinux), we will call a sub make in that other dir, and
35 # after that we are sure that everything which is in that other dir
38 # The only cases where we need to modify files which have global
39 # effects are thus separated out and done before the recursive
40 # descending is started. They are now explicitly listed as the
44 # ---------------------------------------------------------------------------
46 # Normally, we echo the whole command before executing it. By making
47 # that echo $($(quiet)$(cmd)), we now have the possibility to set
48 # $(quiet) to choose other forms of output instead, e.g.
50 # quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
51 # cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
53 # If $(quiet) is empty, the whole command will be printed.
54 # If it is set to "quiet_", only the short version will be printed.
55 # If it is set to "silent_", nothing will be printed at all, since
56 # the variable $(silent_cmd_cc_o_c) doesn't exist.
58 # A simple variant is to prefix commands with $(Q) - that's useful
59 # for commands that shall be hidden in non-verbose mode.
63 # If KBUILD_VERBOSE equals 0 then the above command will be hidden.
64 # If KBUILD_VERBOSE equals 1 then the above command is displayed.
66 # To put more focus on warnings, be less verbose as default
67 # Use 'make V=1' to see the full commands
69 ifeq ("$(origin V)", "command line")
76 ifeq ($(KBUILD_VERBOSE),1)
84 # If the user is running make -s (silent mode), suppress echoing of
87 ifneq ($(filter 4.%,$(MAKE_VERSION)),) # make-4
88 ifneq ($(filter %s ,$(firstword x$(MAKEFLAGS))),)
92 ifneq ($(filter s% -s%,$(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 set on invocation of make in OBJ directory
115 # KBUILD_SRC is not intended to be used by the regular user (for now)
116 ifeq ($(KBUILD_SRC),)
118 # OK, Make called in directory where kernel src resides
119 # Do we want to locate output files in a separate directory?
120 ifeq ("$(origin O)", "command line")
121 KBUILD_OUTPUT := $(O)
124 # That's our default target when none is given on the command line
128 # Cancel implicit rules on top Makefile
129 $(CURDIR)/Makefile Makefile: ;
131 ifneq ($(words $(subst :, ,$(CURDIR))), 1)
132 $(error main directory cannot contain spaces nor colons)
135 ifneq ($(KBUILD_OUTPUT),)
136 # Invoke a second make in the output directory, passing relevant variables
137 # check that the output directory actually exists
138 saved-output := $(KBUILD_OUTPUT)
139 KBUILD_OUTPUT := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) \
141 $(if $(KBUILD_OUTPUT),, \
142 $(error failed to create output directory "$(saved-output)"))
144 PHONY += $(MAKECMDGOALS) sub-make
146 $(filter-out _all sub-make $(CURDIR)/Makefile, $(MAKECMDGOALS)) _all: sub-make
150 $(Q)$(MAKE) -C $(KBUILD_OUTPUT) KBUILD_SRC=$(CURDIR) \
151 -f $(CURDIR)/Makefile $(filter-out _all sub-make,$(MAKECMDGOALS))
153 # Leave processing to above invocation of make
155 endif # ifneq ($(KBUILD_OUTPUT),)
156 endif # ifeq ($(KBUILD_SRC),)
158 # We process the rest of the Makefile if this is the final invocation of make
159 ifeq ($(skip-makefile),)
161 # Do not print "Entering directory ...",
162 # but we want to display it when entering to the output directory
163 # so that IDEs/editors are able to understand relative filenames.
164 MAKEFLAGS += --no-print-directory
166 # Call a source code checker (by default, "sparse") as part of the
169 # Use 'make C=1' to enable checking of only re-compiled files.
170 # Use 'make C=2' to enable checking of *all* source files, regardless
171 # of whether they are re-compiled or not.
173 # See the file "Documentation/sparse.txt" for more details, including
174 # where to get the "sparse" utility.
176 ifeq ("$(origin C)", "command line")
177 KBUILD_CHECKSRC = $(C)
179 ifndef KBUILD_CHECKSRC
183 # Use make M=dir to specify directory of external module to build
184 # Old syntax make ... SUBDIRS=$PWD is still supported
185 # Setting the environment variable KBUILD_EXTMOD take precedence
187 KBUILD_EXTMOD ?= $(SUBDIRS)
190 ifeq ("$(origin M)", "command line")
191 KBUILD_EXTMOD := $(M)
194 # If building an external module we do not care about the all: rule
195 # but instead _all depend on modules
197 ifeq ($(KBUILD_EXTMOD),)
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)
218 VPATH := $(srctree)$(if $(KBUILD_EXTMOD),:$(KBUILD_EXTMOD))
220 export srctree objtree VPATH
222 # SUBARCH tells the usermode build what the underlying arch is. That is set
223 # first, and if a usermode build is happening, the "ARCH=um" on the command
224 # line overrides the setting of ARCH below. If a native build is happening,
225 # then ARCH is assigned, getting whatever value it gets normally, and
226 # SUBARCH is subsequently ignored.
228 SUBARCH := $(shell uname -m | sed -e s/i.86/x86/ -e s/x86_64/x86/ \
229 -e s/sun4u/sparc64/ \
230 -e s/arm.*/arm/ -e s/sa110/arm/ \
231 -e s/s390x/s390/ -e s/parisc64/parisc/ \
232 -e s/ppc.*/powerpc/ -e s/mips.*/mips/ \
233 -e s/sh[234].*/sh/ -e s/aarch64.*/arm64/ )
235 # Cross compiling and selecting different set of gcc/bin-utils
236 # ---------------------------------------------------------------------------
238 # When performing cross compilation for other architectures ARCH shall be set
239 # to the target architecture. (See arch/* for the possibilities).
240 # ARCH can be set during invocation of make:
242 # Another way is to have ARCH set in the environment.
243 # The default ARCH is the host where make is executed.
245 # CROSS_COMPILE specify the prefix used for all executables used
246 # during compilation. Only gcc and related bin-utils executables
247 # are prefixed with $(CROSS_COMPILE).
248 # CROSS_COMPILE can be set on the command line
249 # make CROSS_COMPILE=ia64-linux-
250 # Alternatively CROSS_COMPILE can be set in the environment.
251 # A third alternative is to store a setting in .config so that plain
252 # "make" in the configured kernel build directory always uses that.
253 # Default value for CROSS_COMPILE is not to prefix executables
254 # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
256 CROSS_COMPILE ?= $(CONFIG_CROSS_COMPILE:"%"=%)
258 # Architecture as present in compile.h
259 UTS_MACHINE := $(ARCH)
262 # Additional ARCH settings for x86
266 ifeq ($(ARCH),x86_64)
270 # Additional ARCH settings for sparc
271 ifeq ($(ARCH),sparc32)
274 ifeq ($(ARCH),sparc64)
278 # Additional ARCH settings for sh
283 # Additional ARCH settings for tile
284 ifeq ($(ARCH),tilepro)
287 ifeq ($(ARCH),tilegx)
291 # Where to locate arch specific headers
292 hdr-arch := $(SRCARCH)
294 KCONFIG_CONFIG ?= .config
295 export KCONFIG_CONFIG
297 # SHELL used by kbuild
298 CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
299 else if [ -x /bin/bash ]; then echo /bin/bash; \
300 else echo sh; fi ; fi)
304 HOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 -fomit-frame-pointer -std=gnu89
307 ifeq ($(shell $(HOSTCC) -v 2>&1 | grep -c "clang version"), 1)
308 HOSTCFLAGS += -Wno-unused-value -Wno-unused-parameter \
309 -Wno-missing-field-initializers -fno-delete-null-pointer-checks
312 # Decide whether to build built-in, modular, or both.
313 # Normally, just do built-in.
318 # If we have only "make modules", don't compile built-in objects.
319 # When we're building modules with modversions, we need to consider
320 # the built-in objects during the descend as well, in order to
321 # make sure the checksums are up to date before we record them.
323 ifeq ($(MAKECMDGOALS),modules)
324 KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
327 # If we have "make <whatever> modules", compile modules
328 # in addition to whatever we do anyway.
329 # Just "make" or "make all" shall build modules as well
331 ifneq ($(filter all _all modules,$(MAKECMDGOALS)),)
335 ifeq ($(MAKECMDGOALS),)
339 export KBUILD_MODULES KBUILD_BUILTIN
340 export KBUILD_CHECKSRC KBUILD_SRC KBUILD_EXTMOD
342 # We need some generic definitions (do not try to remake the file).
343 scripts/Kbuild.include: ;
344 include scripts/Kbuild.include
346 # Make variables (CC, etc...)
347 AS = $(CROSS_COMPILE)as
348 LD = $(CROSS_COMPILE)ld
349 CC = $(CROSS_COMPILE)gcc
351 AR = $(CROSS_COMPILE)ar
352 NM = $(CROSS_COMPILE)nm
353 STRIP = $(CROSS_COMPILE)strip
354 OBJCOPY = $(CROSS_COMPILE)objcopy
355 OBJDUMP = $(CROSS_COMPILE)objdump
357 GENKSYMS = scripts/genksyms/genksyms
358 INSTALLKERNEL := installkernel
359 DEPMOD = /sbin/depmod
364 CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
365 -Wbitwise -Wno-return-void $(CF)
373 CFLAGS_GCOV := -fprofile-arcs -ftest-coverage -fno-tree-loop-im $(call cc-disable-warning,maybe-uninitialized,)
374 CFLAGS_KCOV := $(call cc-option,-fsanitize-coverage=trace-pc,)
377 # Use USERINCLUDE when you must reference the UAPI directories only.
379 -I$(srctree)/arch/$(hdr-arch)/include/uapi \
380 -I$(objtree)/arch/$(hdr-arch)/include/generated/uapi \
381 -I$(srctree)/include/uapi \
382 -I$(objtree)/include/generated/uapi \
383 -include $(srctree)/include/linux/kconfig.h
385 # Use LINUXINCLUDE when you must reference the include/ directory.
386 # Needed to be compatible with the O= option
388 -I$(srctree)/arch/$(hdr-arch)/include \
389 -I$(objtree)/arch/$(hdr-arch)/include/generated/uapi \
390 -I$(objtree)/arch/$(hdr-arch)/include/generated \
391 $(if $(KBUILD_SRC), -I$(srctree)/include) \
394 LINUXINCLUDE += $(filter-out $(LINUXINCLUDE),$(USERINCLUDE))
396 KBUILD_CPPFLAGS := -D__KERNEL__
398 KBUILD_CFLAGS := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
399 -fno-strict-aliasing -fno-common \
400 -Werror-implicit-function-declaration \
401 -Wno-format-security \
402 -std=gnu89 $(call cc-option,-fno-PIE)
405 KBUILD_AFLAGS_KERNEL :=
406 KBUILD_CFLAGS_KERNEL :=
407 KBUILD_AFLAGS := -D__ASSEMBLY__ $(call cc-option,-fno-PIE)
408 KBUILD_AFLAGS_MODULE := -DMODULE
409 KBUILD_CFLAGS_MODULE := -DMODULE
410 KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
412 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
413 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
414 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
416 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
417 export ARCH SRCARCH CONFIG_SHELL HOSTCC HOSTCFLAGS CROSS_COMPILE AS LD CC
418 export CPP AR NM STRIP OBJCOPY OBJDUMP
419 export MAKE AWK GENKSYMS INSTALLKERNEL PERL PYTHON UTS_MACHINE
420 export HOSTCXX HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
422 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS LDFLAGS
423 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE CFLAGS_GCOV CFLAGS_KCOV CFLAGS_KASAN CFLAGS_UBSAN
424 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
425 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
426 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
427 export KBUILD_ARFLAGS
429 # When compiling out-of-tree modules, put MODVERDIR in the module
430 # tree rather than in the kernel tree. The kernel tree might
432 export MODVERDIR := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_versions
434 # Files to ignore in find ... statements
436 export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o \
437 -name CVS -o -name .pc -o -name .hg -o -name .git \) \
439 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
440 --exclude CVS --exclude .pc --exclude .hg --exclude .git
442 # ===========================================================================
443 # Rules shared between *config targets and build targets
445 # Basic helpers built in scripts/
446 PHONY += scripts_basic
448 $(Q)$(MAKE) $(build)=scripts/basic
449 $(Q)rm -f .tmp_quiet_recordmcount
451 # To avoid any implicit rule to kick in, define an empty command.
452 scripts/basic/%: scripts_basic ;
454 PHONY += outputmakefile
455 # outputmakefile generates a Makefile in the output directory, if using a
456 # separate output directory. This allows convenient use of make in the
459 ifneq ($(KBUILD_SRC),)
460 $(Q)ln -fsn $(srctree) source
461 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile \
462 $(srctree) $(objtree) $(VERSION) $(PATCHLEVEL)
465 # Support for using generic headers in asm-generic
468 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
469 src=asm obj=arch/$(SRCARCH)/include/generated/asm
470 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
471 src=uapi/asm obj=arch/$(SRCARCH)/include/generated/uapi/asm
473 # To make sure we do not include .config for any of the *config targets
474 # catch them early, and hand them over to scripts/kconfig/Makefile
475 # It is allowed to specify more targets when calling make, including
476 # mixing *config targets and build targets.
477 # For example 'make oldconfig all'.
478 # Detect when mixed targets is specified, and make a second invocation
479 # of make so .config is not included in this case either (for *config).
481 version_h := include/generated/uapi/linux/version.h
482 old_version_h := include/linux/version.h
484 no-dot-config-targets := clean mrproper distclean \
485 cscope gtags TAGS tags help% %docs check% coccicheck \
486 $(version_h) headers_% archheaders archscripts \
487 kernelversion %src-pkg
493 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
494 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
499 ifeq ($(KBUILD_EXTMOD),)
500 ifneq ($(filter config %config,$(MAKECMDGOALS)),)
502 ifneq ($(words $(MAKECMDGOALS)),1)
507 # install and module_install need also be processed one by one
508 ifneq ($(filter install,$(MAKECMDGOALS)),)
509 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
514 ifeq ($(mixed-targets),1)
515 # ===========================================================================
516 # We're called with mixed targets (*config and build targets).
517 # Handle them one by one.
519 PHONY += $(MAKECMDGOALS) __build_one_by_one
521 $(filter-out __build_one_by_one, $(MAKECMDGOALS)): __build_one_by_one
526 for i in $(MAKECMDGOALS); do \
527 $(MAKE) -f $(srctree)/Makefile $$i; \
531 ifeq ($(config-targets),1)
532 # ===========================================================================
533 # *config targets only - make sure prerequisites are updated, and descend
534 # in scripts/kconfig to make the *config target
536 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
537 # KBUILD_DEFCONFIG may point out an alternative default configuration
538 # used for 'make defconfig'
539 include arch/$(SRCARCH)/Makefile
540 export KBUILD_DEFCONFIG KBUILD_KCONFIG
542 config: scripts_basic outputmakefile FORCE
543 $(Q)$(MAKE) $(build)=scripts/kconfig $@
545 %config: scripts_basic outputmakefile FORCE
546 $(Q)$(MAKE) $(build)=scripts/kconfig $@
549 # ===========================================================================
550 # Build targets only - this includes vmlinux, arch specific targets, clean
551 # targets and others. In general all targets except *config targets.
553 ifeq ($(KBUILD_EXTMOD),)
554 # Additional helpers built in scripts/
555 # Carefully list dependencies so we do not try to build scripts twice
558 scripts: scripts_basic include/config/auto.conf include/config/tristate.conf \
559 asm-generic gcc-plugins
560 $(Q)$(MAKE) $(build)=$(@)
562 # Objects we will link into vmlinux / subdirs we need to visit
564 drivers-y := drivers/ sound/ firmware/
569 endif # KBUILD_EXTMOD
571 ifeq ($(dot-config),1)
573 -include include/config/auto.conf
575 ifeq ($(KBUILD_EXTMOD),)
576 # Read in dependencies to all Kconfig* files, make sure to run
577 # oldconfig if changes are detected.
578 -include include/config/auto.conf.cmd
580 # To avoid any implicit rule to kick in, define an empty command
581 $(KCONFIG_CONFIG) include/config/auto.conf.cmd: ;
583 # If .config is newer than include/config/auto.conf, someone tinkered
584 # with it and forgot to run make oldconfig.
585 # if auto.conf.cmd is missing then we are probably in a cleaned tree so
586 # we execute the config step to be sure to catch updated Kconfig files
587 include/config/%.conf: $(KCONFIG_CONFIG) include/config/auto.conf.cmd
588 $(Q)$(MAKE) -f $(srctree)/Makefile silentoldconfig
590 # external modules needs include/generated/autoconf.h and include/config/auto.conf
591 # but do not care if they are up-to-date. Use auto.conf to trigger the test
592 PHONY += include/config/auto.conf
594 include/config/auto.conf:
595 $(Q)test -e include/generated/autoconf.h -a -e $@ || ( \
597 echo >&2 " ERROR: Kernel configuration is invalid."; \
598 echo >&2 " include/generated/autoconf.h or $@ are missing.";\
599 echo >&2 " Run 'make oldconfig && make prepare' on kernel src to fix it."; \
603 endif # KBUILD_EXTMOD
606 # Dummy target needed, because used as prerequisite
607 include/config/auto.conf: ;
608 endif # $(dot-config)
610 # For the kernel to actually contain only the needed exported symbols,
611 # we have to build modules as well to determine what those symbols are.
612 # (this can be evaluated only once include/config/auto.conf has been included)
613 ifdef CONFIG_TRIM_UNUSED_KSYMS
617 # The all: target is the default when no target is given on the
619 # This allow a user to issue only 'make' to build a kernel including modules
620 # Defaults to vmlinux, but the arch makefile usually adds further targets
623 # The arch Makefile can set ARCH_{CPP,A,C}FLAGS to override the default
624 # values of the respective KBUILD_* variables
628 include arch/$(SRCARCH)/Makefile
630 KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,)
631 KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,)
632 KBUILD_CFLAGS += $(call cc-disable-warning, format-truncation)
633 KBUILD_CFLAGS += $(call cc-disable-warning, format-overflow)
634 KBUILD_CFLAGS += $(call cc-disable-warning, int-in-bool-context)
636 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
637 KBUILD_CFLAGS += $(call cc-option,-ffunction-sections,)
638 KBUILD_CFLAGS += $(call cc-option,-fdata-sections,)
641 ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
642 KBUILD_CFLAGS += $(call cc-option,-Oz,-Os)
643 KBUILD_CFLAGS += $(call cc-disable-warning,maybe-uninitialized,)
645 ifdef CONFIG_PROFILE_ALL_BRANCHES
646 KBUILD_CFLAGS += -O2 $(call cc-disable-warning,maybe-uninitialized,)
652 KBUILD_CFLAGS += $(call cc-ifversion, -lt, 0409, \
653 $(call cc-disable-warning,maybe-uninitialized,))
655 # Tell gcc to never replace conditional load with a non-conditional one
656 KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
658 # check for 'asm goto'
659 ifeq ($(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC) $(KBUILD_CFLAGS)), y)
660 KBUILD_CFLAGS += -DCC_HAVE_ASM_GOTO
661 KBUILD_AFLAGS += -DCC_HAVE_ASM_GOTO
664 include scripts/Makefile.gcc-plugins
666 ifdef CONFIG_READABLE_ASM
667 # Disable optimizations that make assembler listings hard to read.
668 # reorder blocks reorders the control in the function
669 # ipa clone creates specialized cloned functions
670 # partial inlining inlines only parts of functions
671 KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
672 $(call cc-option,-fno-ipa-cp-clone,) \
673 $(call cc-option,-fno-partial-inlining)
676 ifneq ($(CONFIG_FRAME_WARN),0)
677 KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
680 # This selects the stack protector compiler flag. Testing it is delayed
681 # until after .config has been reprocessed, in the prepare-compiler-check
683 ifdef CONFIG_CC_STACKPROTECTOR_REGULAR
684 stackp-flag := -fstack-protector
685 stackp-name := REGULAR
687 ifdef CONFIG_CC_STACKPROTECTOR_STRONG
688 stackp-flag := -fstack-protector-strong
689 stackp-name := STRONG
691 # Force off for distro compilers that enable stack protector by default.
692 stackp-flag := $(call cc-option, -fno-stack-protector)
695 # Find arch-specific stack protector compiler sanity-checking script.
696 ifdef CONFIG_CC_STACKPROTECTOR
697 stackp-path := $(srctree)/scripts/gcc-$(SRCARCH)_$(BITS)-has-stack-protector.sh
698 stackp-check := $(wildcard $(stackp-path))
700 KBUILD_CFLAGS += $(stackp-flag)
702 ifeq ($(cc-name),clang)
703 ifneq ($(CROSS_COMPILE),)
704 CLANG_TRIPLE ?= $(CROSS_COMPILE)
705 CLANG_TARGET := --target=$(notdir $(CLANG_TRIPLE:%-=%))
706 GCC_TOOLCHAIN := $(realpath $(dir $(shell which $(LD)))/..)
708 ifneq ($(GCC_TOOLCHAIN),)
709 CLANG_GCC_TC := --gcc-toolchain=$(GCC_TOOLCHAIN)
711 KBUILD_CFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC)
712 KBUILD_AFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC)
713 KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
714 KBUILD_CFLAGS += $(call cc-disable-warning, unused-variable)
715 KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier)
716 KBUILD_CFLAGS += $(call cc-disable-warning, gnu)
717 KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
718 KBUILD_CFLAGS += $(call cc-disable-warning, duplicate-decl-specifier)
719 # Quiet clang warning: comparison of unsigned expression < 0 is always false
720 KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare)
721 # CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
722 # source of a reference will be _MergedGlobals and not on of the whitelisted names.
723 # See modpost pattern 2
724 KBUILD_CFLAGS += $(call cc-option, -mno-global-merge,)
725 KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior)
726 KBUILD_CFLAGS += $(call cc-option, -no-integrated-as)
727 KBUILD_AFLAGS += $(call cc-option, -no-integrated-as)
730 # These warnings generated too much noise in a regular build.
731 # Use make W=1 to enable them (see scripts/Makefile.build)
732 KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
733 KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
736 ifdef CONFIG_FRAME_POINTER
737 KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
739 # Some targets (ARM with Thumb2, for example), can't be built with frame
740 # pointers. For those, we don't have FUNCTION_TRACER automatically
741 # select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
742 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
743 # -fomit-frame-pointer with FUNCTION_TRACER.
744 ifndef CONFIG_FUNCTION_TRACER
745 KBUILD_CFLAGS += -fomit-frame-pointer
749 KBUILD_CFLAGS += $(call cc-option, -fno-var-tracking-assignments)
751 ifdef CONFIG_DEBUG_INFO
752 ifdef CONFIG_DEBUG_INFO_SPLIT
753 KBUILD_CFLAGS += $(call cc-option, -gsplit-dwarf, -g)
757 KBUILD_AFLAGS += -Wa,-gdwarf-2
759 ifdef CONFIG_DEBUG_INFO_DWARF4
760 KBUILD_CFLAGS += $(call cc-option, -gdwarf-4,)
763 ifdef CONFIG_DEBUG_INFO_REDUCED
764 KBUILD_CFLAGS += $(call cc-option, -femit-struct-debug-baseonly) \
765 $(call cc-option,-fno-var-tracking)
768 ifdef CONFIG_FUNCTION_TRACER
769 ifndef CC_FLAGS_FTRACE
770 CC_FLAGS_FTRACE := -pg
772 export CC_FLAGS_FTRACE
773 ifdef CONFIG_HAVE_FENTRY
774 CC_USING_FENTRY := $(call cc-option, -mfentry -DCC_USING_FENTRY)
776 KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_USING_FENTRY)
777 KBUILD_AFLAGS += $(CC_USING_FENTRY)
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 # arch Makefile may override CC so keep this after arch Makefile is included
792 NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
793 CHECKFLAGS += $(NOSTDINC_FLAGS)
795 # warn about C99 declaration after statement
796 KBUILD_CFLAGS += $(call cc-option,-Wdeclaration-after-statement,)
798 # disable pointer signed / unsigned warnings in gcc 4.0
799 KBUILD_CFLAGS += $(call cc-disable-warning, pointer-sign)
801 # disable invalid "can't wrap" optimizations for signed / pointers
802 KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow)
804 # conserve stack if available
805 KBUILD_CFLAGS += $(call cc-option,-fconserve-stack)
807 # disallow errors like 'EXPORT_GPL(foo);' with missing header
808 KBUILD_CFLAGS += $(call cc-option,-Werror=implicit-int)
810 # require functions to have arguments in prototypes, not empty 'int foo()'
811 KBUILD_CFLAGS += $(call cc-option,-Werror=strict-prototypes)
813 # Prohibit date/time macros, which would make the build non-deterministic
814 KBUILD_CFLAGS += $(call cc-option,-Werror=date-time)
816 # enforce correct pointer usage
817 KBUILD_CFLAGS += $(call cc-option,-Werror=incompatible-pointer-types)
819 # use the deterministic mode of AR if available
820 KBUILD_ARFLAGS := $(call ar-option,D)
822 include scripts/Makefile.kasan
823 include scripts/Makefile.extrawarn
824 include scripts/Makefile.ubsan
826 # Add any arch overrides and user supplied CPPFLAGS, AFLAGS and CFLAGS as the
828 KBUILD_CPPFLAGS += $(ARCH_CPPFLAGS) $(KCPPFLAGS)
829 KBUILD_AFLAGS += $(ARCH_AFLAGS) $(KAFLAGS)
830 KBUILD_CFLAGS += $(ARCH_CFLAGS) $(KCFLAGS)
832 # Use --build-id when available.
833 LDFLAGS_BUILD_ID = $(patsubst -Wl$(comma)%,%,\
834 $(call cc-ldoption, -Wl$(comma)--build-id,))
835 KBUILD_LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID)
836 LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)
838 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
839 LDFLAGS_vmlinux += $(call ld-option, --gc-sections,)
842 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
843 LDFLAGS_vmlinux += $(call ld-option, -X,)
846 # Default kernel image to build when no specific target is given.
847 # KBUILD_IMAGE may be overruled on the command line or
848 # set in the environment
849 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
851 export KBUILD_IMAGE ?= vmlinux
854 # INSTALL_PATH specifies where to place the updated kernel and system map
855 # images. Default is /boot, but you can set it to other values
856 export INSTALL_PATH ?= /boot
859 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
860 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
861 # an argument if needed. Otherwise it defaults to the kernel install path
863 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
866 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
867 # relocations required by build roots. This is not defined in the
868 # makefile but the argument can be passed to make if needed.
871 MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
875 # INSTALL_MOD_STRIP, if defined, will cause modules to be
876 # stripped after they are installed. If INSTALL_MOD_STRIP is '1', then
877 # the default option --strip-debug will be used. Otherwise,
878 # INSTALL_MOD_STRIP value will be used as the options to the strip command.
880 ifdef INSTALL_MOD_STRIP
881 ifeq ($(INSTALL_MOD_STRIP),1)
882 mod_strip_cmd = $(STRIP) --strip-debug
884 mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
885 endif # INSTALL_MOD_STRIP=1
888 endif # INSTALL_MOD_STRIP
891 # CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
892 # after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
893 # or CONFIG_MODULE_COMPRESS_XZ.
895 mod_compress_cmd = true
896 ifdef CONFIG_MODULE_COMPRESS
897 ifdef CONFIG_MODULE_COMPRESS_GZIP
898 mod_compress_cmd = gzip -n -f
899 endif # CONFIG_MODULE_COMPRESS_GZIP
900 ifdef CONFIG_MODULE_COMPRESS_XZ
901 mod_compress_cmd = xz -f
902 endif # CONFIG_MODULE_COMPRESS_XZ
903 endif # CONFIG_MODULE_COMPRESS
904 export mod_compress_cmd
906 # Select initial ramdisk compression format, default is gzip(1).
907 # This shall be used by the dracut(8) tool while creating an initramfs image.
909 INITRD_COMPRESS-y := gzip
910 INITRD_COMPRESS-$(CONFIG_RD_BZIP2) := bzip2
911 INITRD_COMPRESS-$(CONFIG_RD_LZMA) := lzma
912 INITRD_COMPRESS-$(CONFIG_RD_XZ) := xz
913 INITRD_COMPRESS-$(CONFIG_RD_LZO) := lzo
914 INITRD_COMPRESS-$(CONFIG_RD_LZ4) := lz4
915 # do not export INITRD_COMPRESS, since we didn't actually
916 # choose a sane default compression above.
917 # export INITRD_COMPRESS := $(INITRD_COMPRESS-y)
919 ifdef CONFIG_MODULE_SIG_ALL
920 $(eval $(call config_filename,MODULE_SIG_KEY))
922 mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
929 ifeq ($(KBUILD_EXTMOD),)
930 core-y += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
932 vmlinux-dirs := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
933 $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
934 $(net-y) $(net-m) $(libs-y) $(libs-m) $(virt-y)))
936 vmlinux-alldirs := $(sort $(vmlinux-dirs) $(patsubst %/,%,$(filter %/, \
937 $(init-) $(core-) $(drivers-) $(net-) $(libs-) $(virt-))))
939 init-y := $(patsubst %/, %/built-in.o, $(init-y))
940 core-y := $(patsubst %/, %/built-in.o, $(core-y))
941 drivers-y := $(patsubst %/, %/built-in.o, $(drivers-y))
942 net-y := $(patsubst %/, %/built-in.o, $(net-y))
943 libs-y1 := $(patsubst %/, %/lib.a, $(libs-y))
944 libs-y2 := $(patsubst %/, %/built-in.o, $(libs-y))
945 libs-y := $(libs-y1) $(libs-y2)
946 virt-y := $(patsubst %/, %/built-in.o, $(virt-y))
948 # Externally visible symbols (used by link-vmlinux.sh)
949 export KBUILD_VMLINUX_INIT := $(head-y) $(init-y)
950 export KBUILD_VMLINUX_MAIN := $(core-y) $(libs-y) $(drivers-y) $(net-y) $(virt-y)
951 export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
952 export LDFLAGS_vmlinux
953 # used by scripts/pacmage/Makefile
954 export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) arch Documentation include samples scripts tools)
956 vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_INIT) $(KBUILD_VMLINUX_MAIN)
958 # Include targets which we want to execute sequentially if the rest of the
959 # kernel build went well. If CONFIG_TRIM_UNUSED_KSYMS is set, this might be
960 # evaluated more than once.
961 PHONY += vmlinux_prereq
962 vmlinux_prereq: $(vmlinux-deps) FORCE
963 ifdef CONFIG_HEADERS_CHECK
964 $(Q)$(MAKE) -f $(srctree)/Makefile headers_check
966 ifdef CONFIG_GDB_SCRIPTS
967 $(Q)ln -fsn `cd $(srctree) && /bin/pwd`/scripts/gdb/vmlinux-gdb.py
969 ifdef CONFIG_TRIM_UNUSED_KSYMS
970 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
971 "$(MAKE) -f $(srctree)/Makefile vmlinux"
974 # standalone target for easier testing
975 include/generated/autoksyms.h: FORCE
976 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh true
978 ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
980 # Final link of vmlinux with optional arch pass after final link
982 $(CONFIG_SHELL) $< $(LD) $(LDFLAGS) $(LDFLAGS_vmlinux) ; \
983 $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
985 vmlinux: scripts/link-vmlinux.sh vmlinux_prereq $(vmlinux-deps) FORCE
986 +$(call if_changed,link-vmlinux)
988 # Build samples along the rest of the kernel
990 vmlinux-dirs += samples
993 # The actual objects are generated when descending,
994 # make sure no implicit rule kicks in
995 $(sort $(vmlinux-deps)): $(vmlinux-dirs) ;
997 # Handle descending into subdirectories listed in $(vmlinux-dirs)
998 # Preset locale variables to speed up the build process. Limit locale
999 # tweaks to this spot to avoid wrong language settings when running
1000 # make menuconfig etc.
1001 # Error messages still appears in the original language
1003 PHONY += $(vmlinux-dirs)
1004 $(vmlinux-dirs): prepare scripts
1005 $(Q)$(MAKE) $(build)=$@
1007 define filechk_kernel.release
1008 echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1011 # Store (new) KERNELRELEASE string in include/config/kernel.release
1012 include/config/kernel.release: include/config/auto.conf FORCE
1013 $(call filechk,kernel.release)
1016 # Things we need to do before we recursively start building the kernel
1017 # or the modules are listed in "prepare".
1018 # A multi level approach is used. prepareN is processed before prepareN-1.
1019 # archprepare is used in arch Makefiles and when processed asm symlink,
1020 # version.h and scripts_basic is processed / created.
1022 # Listed in dependency order
1023 PHONY += prepare archprepare prepare0 prepare1 prepare2 prepare3
1025 # prepare3 is used to check if we are building in a separate output directory,
1027 # 1) Check that make has not been executed in the kernel src $(srctree)
1028 prepare3: include/config/kernel.release
1029 ifneq ($(KBUILD_SRC),)
1030 @$(kecho) ' Using $(srctree) as source for kernel'
1031 $(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \
1032 echo >&2 " $(srctree) is not clean, please run 'make mrproper'"; \
1033 echo >&2 " in the '$(srctree)' directory.";\
1038 # prepare2 creates a makefile if using a separate output directory.
1039 # From this point forward, .config has been reprocessed, so any rules
1040 # that need to depend on updated CONFIG_* values can be checked here.
1041 prepare2: prepare3 prepare-compiler-check outputmakefile asm-generic
1043 prepare1: prepare2 $(version_h) include/generated/utsrelease.h \
1044 include/config/auto.conf
1047 archprepare: archheaders archscripts prepare1 scripts_basic
1049 prepare0: archprepare gcc-plugins
1050 $(Q)$(MAKE) $(build)=.
1052 # All the preparing..
1053 prepare: prepare0 prepare-objtool
1055 ifdef CONFIG_STACK_VALIDATION
1056 has_libelf := $(call try-run,\
1057 echo "int main() {}" | $(HOSTCC) -xc -o /dev/null -lelf -,1,0)
1058 ifeq ($(has_libelf),1)
1059 objtool_target := tools/objtool FORCE
1061 $(warning "Cannot use CONFIG_STACK_VALIDATION, please install libelf-dev, libelf-devel or elfutils-libelf-devel")
1062 SKIP_STACK_VALIDATION := 1
1063 export SKIP_STACK_VALIDATION
1067 PHONY += prepare-objtool
1068 prepare-objtool: $(objtool_target)
1070 # Check for CONFIG flags that require compiler support. Abort the build
1071 # after .config has been processed, but before the kernel build starts.
1073 # For security-sensitive CONFIG options, we don't want to fallback and/or
1074 # silently change which compiler flags will be used, since that leads to
1075 # producing kernels with different security feature characteristics
1076 # depending on the compiler used. (For example, "But I selected
1077 # CC_STACKPROTECTOR_STRONG! Why did it build with _REGULAR?!")
1078 PHONY += prepare-compiler-check
1079 prepare-compiler-check: FORCE
1080 # Make sure compiler supports requested stack protector flag.
1082 ifeq ($(call cc-option, $(stackp-flag)),)
1083 @echo Cannot use CONFIG_CC_STACKPROTECTOR_$(stackp-name): \
1084 $(stackp-flag) not supported by compiler >&2 && exit 1
1087 # Make sure compiler does not have buggy stack-protector support.
1089 ifneq ($(shell $(CONFIG_SHELL) $(stackp-check) $(CC) $(KBUILD_CPPFLAGS) $(biarch)),y)
1090 @echo Cannot use CONFIG_CC_STACKPROTECTOR_$(stackp-name): \
1091 $(stackp-flag) available but compiler is broken >&2 && exit 1
1096 # Generate some files
1097 # ---------------------------------------------------------------------------
1099 # KERNELRELEASE can change from a few different places, meaning version.h
1100 # needs to be updated, so this check is forced on all builds
1103 define filechk_utsrelease.h
1104 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1105 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1108 (echo \#define UTS_RELEASE \"$(KERNELRELEASE)\";)
1111 define filechk_version.h
1112 (echo \#define LINUX_VERSION_CODE $(shell \
1113 expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1114 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))';)
1117 $(version_h): $(srctree)/Makefile FORCE
1118 $(call filechk,version.h)
1119 $(Q)rm -f $(old_version_h)
1121 include/generated/utsrelease.h: include/config/kernel.release FORCE
1122 $(call filechk,utsrelease.h)
1126 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1127 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1129 # ---------------------------------------------------------------------------
1131 INSTALL_FW_PATH=$(INSTALL_MOD_PATH)/lib/firmware
1132 export INSTALL_FW_PATH
1134 PHONY += firmware_install
1136 @mkdir -p $(objtree)/firmware
1137 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_install
1139 # ---------------------------------------------------------------------------
1142 #Default location for installed headers
1143 export INSTALL_HDR_PATH = $(objtree)/usr
1145 # If we do an all arch process set dst to asm-$(hdr-arch)
1146 hdr-dst = $(if $(KBUILD_HEADERS), dst=include/asm-$(hdr-arch), dst=include/asm)
1148 PHONY += archheaders
1151 PHONY += archscripts
1155 __headers: $(version_h) scripts_basic asm-generic archheaders archscripts
1156 $(Q)$(MAKE) $(build)=scripts build_unifdef
1158 PHONY += headers_install_all
1159 headers_install_all:
1160 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh install
1162 PHONY += headers_install
1163 headers_install: __headers
1164 $(if $(wildcard $(srctree)/arch/$(hdr-arch)/include/uapi/asm/Kbuild),, \
1165 $(error Headers not exportable for the $(SRCARCH) architecture))
1166 $(Q)$(MAKE) $(hdr-inst)=include/uapi
1167 $(Q)$(MAKE) $(hdr-inst)=arch/$(hdr-arch)/include/uapi/asm $(hdr-dst)
1169 PHONY += headers_check_all
1170 headers_check_all: headers_install_all
1171 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh check
1173 PHONY += headers_check
1174 headers_check: headers_install
1175 $(Q)$(MAKE) $(hdr-inst)=include/uapi HDRCHECK=1
1176 $(Q)$(MAKE) $(hdr-inst)=arch/$(hdr-arch)/include/uapi/asm $(hdr-dst) HDRCHECK=1
1178 # ---------------------------------------------------------------------------
1183 $(Q)$(MAKE) -C tools/testing/selftests run_tests
1186 $(Q)$(MAKE) -C tools/testing/selftests clean
1188 PHONY += kselftest-merge
1190 $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1191 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/kconfig/merge_config.sh \
1192 -m $(objtree)/.config \
1193 $(srctree)/tools/testing/selftests/*/config
1194 +$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1196 # ---------------------------------------------------------------------------
1199 ifdef CONFIG_MODULES
1201 # By default, build modules as well
1207 # A module can be listed more than once in obj-m resulting in
1208 # duplicate lines in modules.order files. Those are removed
1209 # using awk while concatenating to the final file.
1212 modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux) modules.builtin
1213 $(Q)$(AWK) '!x[$$0]++' $(vmlinux-dirs:%=$(objtree)/%/modules.order) > $(objtree)/modules.order
1214 @$(kecho) ' Building modules, stage 2.';
1215 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1216 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_modbuild
1218 modules.builtin: $(vmlinux-dirs:%=%/modules.builtin)
1219 $(Q)$(AWK) '!x[$$0]++' $^ > $(objtree)/modules.builtin
1221 %/modules.builtin: include/config/auto.conf
1222 $(Q)$(MAKE) $(modbuiltin)=$*
1225 # Target to prepare building external modules
1226 PHONY += modules_prepare
1227 modules_prepare: prepare scripts
1229 # Target to install modules
1230 PHONY += modules_install
1231 modules_install: _modinst_ _modinst_post
1235 @rm -rf $(MODLIB)/kernel
1236 @rm -f $(MODLIB)/source
1237 @mkdir -p $(MODLIB)/kernel
1238 @ln -s `cd $(srctree) && /bin/pwd` $(MODLIB)/source
1239 @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
1240 rm -f $(MODLIB)/build ; \
1241 ln -s $(CURDIR) $(MODLIB)/build ; \
1243 @cp -f $(objtree)/modules.order $(MODLIB)/
1244 @cp -f $(objtree)/modules.builtin $(MODLIB)/
1245 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1247 # This depmod is only for convenience to give the initial
1248 # boot a modules.dep even before / is mounted read-write. However the
1249 # boot script depmod is the master version.
1250 PHONY += _modinst_post
1251 _modinst_post: _modinst_
1252 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_modinst
1255 ifeq ($(CONFIG_MODULE_SIG), y)
1256 PHONY += modules_sign
1258 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1261 else # CONFIG_MODULES
1263 # Modules not configured
1264 # ---------------------------------------------------------------------------
1266 PHONY += modules modules_install
1267 modules modules_install:
1269 @echo >&2 "The present kernel configuration has modules disabled."
1270 @echo >&2 "Type 'make config' and enable loadable module support."
1271 @echo >&2 "Then build a kernel with module support enabled."
1275 endif # CONFIG_MODULES
1278 # Cleaning is done on three levels.
1279 # make clean Delete most generated files
1280 # Leave enough to build external modules
1281 # make mrproper Delete the current configuration, and all generated files
1282 # make distclean Remove editor backup files, patch leftover files and the like
1284 # Directories & files removed with 'make clean'
1285 CLEAN_DIRS += $(MODVERDIR)
1287 # Directories & files removed with 'make mrproper'
1288 MRPROPER_DIRS += include/config usr/include include/generated \
1289 arch/*/include/generated .tmp_objdiff
1290 MRPROPER_FILES += .config .config.old .version .old_version \
1291 Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS \
1292 signing_key.pem signing_key.priv signing_key.x509 \
1293 x509.genkey extra_certificates signing_key.x509.keyid \
1294 signing_key.x509.signer vmlinux-gdb.py
1296 # clean - Delete most, but leave enough to build external modules
1298 clean: rm-dirs := $(CLEAN_DIRS)
1299 clean: rm-files := $(CLEAN_FILES)
1300 clean-dirs := $(addprefix _clean_, . $(vmlinux-alldirs) Documentation samples)
1302 PHONY += $(clean-dirs) clean archclean vmlinuxclean
1304 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1307 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1308 $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1310 clean: archclean vmlinuxclean
1312 # mrproper - Delete all generated files, including .config
1314 mrproper: rm-dirs := $(wildcard $(MRPROPER_DIRS))
1315 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1316 mrproper-dirs := $(addprefix _mrproper_,Documentation/DocBook scripts)
1318 PHONY += $(mrproper-dirs) mrproper archmrproper
1320 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1322 mrproper: clean archmrproper $(mrproper-dirs)
1331 @find $(srctree) $(RCS_FIND_IGNORE) \
1332 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1333 -o -name '*.bak' -o -name '#*#' -o -name '.*.orig' \
1334 -o -name '.*.rej' -o -name '*%' -o -name 'core' \) \
1335 -type f -print | xargs rm -f
1338 # Packaging of the kernel to various formats
1339 # ---------------------------------------------------------------------------
1340 # rpm target kept for backward compatibility
1341 package-dir := scripts/package
1344 $(Q)$(MAKE) $(build)=$(package-dir) $@
1345 %pkg: include/config/kernel.release FORCE
1346 $(Q)$(MAKE) $(build)=$(package-dir) $@
1347 rpm: include/config/kernel.release FORCE
1348 $(Q)$(MAKE) $(build)=$(package-dir) $@
1351 # Brief documentation of the typical targets used
1352 # ---------------------------------------------------------------------------
1354 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1355 boards := $(sort $(notdir $(boards)))
1356 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1357 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1361 @echo 'Cleaning targets:'
1362 @echo ' clean - Remove most generated files but keep the config and'
1363 @echo ' enough build support to build external modules'
1364 @echo ' mrproper - Remove all generated files + config + various backup files'
1365 @echo ' distclean - mrproper + remove editor backup and patch files'
1367 @echo 'Configuration targets:'
1368 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1370 @echo 'Other generic targets:'
1371 @echo ' all - Build all targets marked with [*]'
1372 @echo '* vmlinux - Build the bare kernel'
1373 @echo '* modules - Build all modules'
1374 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1375 @echo ' firmware_install- Install all firmware to INSTALL_FW_PATH'
1376 @echo ' (default: $$(INSTALL_MOD_PATH)/lib/firmware)'
1377 @echo ' dir/ - Build all files in dir and below'
1378 @echo ' dir/file.[ois] - Build specified target only'
1379 @echo ' dir/file.ll - Build the LLVM assembly file'
1380 @echo ' (requires compiler support for LLVM assembly generation)'
1381 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1382 @echo ' (requires a recent binutils and recent build (System.map))'
1383 @echo ' dir/file.ko - Build module including final link'
1384 @echo ' modules_prepare - Set up for building external modules'
1385 @echo ' tags/TAGS - Generate tags file for editors'
1386 @echo ' cscope - Generate cscope index'
1387 @echo ' gtags - Generate GNU GLOBAL index'
1388 @echo ' kernelrelease - Output the release version string (use with make -s)'
1389 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1390 @echo ' image_name - Output the image name (use with make -s)'
1391 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1392 echo ' (default: $(INSTALL_HDR_PATH))'; \
1394 @echo 'Static analysers'
1395 @echo ' checkstack - Generate a list of stack hogs'
1396 @echo ' namespacecheck - Name space analysis on compiled kernel'
1397 @echo ' versioncheck - Sanity check on version.h usage'
1398 @echo ' includecheck - Check for duplicate included header files'
1399 @echo ' export_report - List the usages of all exported symbols'
1400 @echo ' headers_check - Sanity check on exported headers'
1401 @echo ' headerdep - Detect inclusion cycles in headers'
1402 @$(MAKE) -f $(srctree)/scripts/Makefile.help checker-help
1404 @echo 'Kernel selftest'
1405 @echo ' kselftest - Build and run kernel selftest (run as root)'
1406 @echo ' Build, install, and boot kernel before'
1407 @echo ' running kselftest on it'
1408 @echo ' kselftest-clean - Remove all generated kselftest files'
1409 @echo ' kselftest-merge - Merge all the config dependencies of kselftest to existed'
1412 @echo 'Kernel packaging:'
1413 @$(MAKE) $(build)=$(package-dir) help
1415 @echo 'Documentation targets:'
1416 @$(MAKE) -f $(srctree)/Documentation/Makefile.sphinx dochelp
1418 @$(MAKE) -f $(srctree)/Documentation/DocBook/Makefile dochelp
1420 @echo 'Architecture specific targets ($(SRCARCH)):'
1421 @$(if $(archhelp),$(archhelp),\
1422 echo ' No architecture specific help defined for $(SRCARCH)')
1425 $(foreach b, $(boards), \
1426 printf " %-24s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1428 @$(if $(board-dirs), \
1429 $(foreach b, $(board-dirs), \
1430 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1431 printf " %-16s - Show all of the above\\n" help-boards; \
1434 @echo ' make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1435 @echo ' make V=2 [targets] 2 => give reason for rebuild of target'
1436 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1437 @echo ' make C=1 [targets] Check all c source with $$CHECK (sparse by default)'
1438 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1439 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1440 @echo ' make W=n [targets] Enable extra gcc checks, n=1,2,3 where'
1441 @echo ' 1: warnings which may be relevant and do not occur too often'
1442 @echo ' 2: warnings which occur quite often but may still be relevant'
1443 @echo ' 3: more obscure warnings, can most likely be ignored'
1444 @echo ' Multiple levels can be combined with W=12 or W=123'
1446 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1447 @echo 'For further info see the ./README file'
1450 help-board-dirs := $(addprefix help-,$(board-dirs))
1452 help-boards: $(help-board-dirs)
1454 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1456 $(help-board-dirs): help-%:
1457 @echo 'Architecture specific targets ($(SRCARCH) $*):'
1458 @$(if $(boards-per-dir), \
1459 $(foreach b, $(boards-per-dir), \
1460 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1464 # Documentation targets
1465 # ---------------------------------------------------------------------------
1466 DOC_TARGETS := xmldocs sgmldocs psdocs latexdocs pdfdocs htmldocs mandocs installmandocs epubdocs cleandocs
1467 PHONY += $(DOC_TARGETS)
1468 $(DOC_TARGETS): scripts_basic FORCE
1469 $(Q)$(MAKE) $(build)=scripts build_docproc build_check-lc_ctype
1470 $(Q)$(MAKE) $(build)=Documentation -f $(srctree)/Documentation/Makefile.sphinx $@
1471 $(Q)$(MAKE) $(build)=Documentation/DocBook $@
1473 else # KBUILD_EXTMOD
1476 # External module support.
1477 # When building external modules the kernel used as basis is considered
1478 # read-only, and no consistency checks are made and the make
1479 # system is not used on the basis kernel. If updates are required
1480 # in the basis kernel ordinary make commands (without M=...) must
1483 # The following are the only valid targets when building external
1485 # make M=dir clean Delete all automatically generated files
1486 # make M=dir modules Make all modules in specified dir
1487 # make M=dir Same as 'make M=dir modules'
1488 # make M=dir modules_install
1489 # Install the modules built in the module directory
1490 # Assumes install directory is already created
1492 # We are always building modules
1494 PHONY += crmodverdir
1498 PHONY += $(objtree)/Module.symvers
1499 $(objtree)/Module.symvers:
1500 @test -e $(objtree)/Module.symvers || ( \
1502 echo " WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1503 echo " is missing; modules will have no dependencies and modversions."; \
1506 module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
1507 PHONY += $(module-dirs) modules
1508 $(module-dirs): crmodverdir $(objtree)/Module.symvers
1509 $(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@)
1511 modules: $(module-dirs)
1512 @$(kecho) ' Building modules, stage 2.';
1513 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1515 PHONY += modules_install
1516 modules_install: _emodinst_ _emodinst_post
1518 install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1521 $(Q)mkdir -p $(MODLIB)/$(install-dir)
1522 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1524 PHONY += _emodinst_post
1525 _emodinst_post: _emodinst_
1528 clean-dirs := $(addprefix _clean_,$(KBUILD_EXTMOD))
1530 PHONY += $(clean-dirs) clean
1532 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1534 clean: rm-dirs := $(MODVERDIR)
1535 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers
1539 @echo ' Building external modules.'
1540 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1542 @echo ' modules - default target, build the module(s)'
1543 @echo ' modules_install - install the module'
1544 @echo ' clean - remove generated files in module directory only'
1548 PHONY += prepare scripts
1551 endif # KBUILD_EXTMOD
1553 clean: $(clean-dirs)
1556 @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1557 \( -name '*.[oas]' -o -name '*.ko' -o -name '.*.cmd' \
1561 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1562 -o -name '*.symtypes' -o -name 'modules.order' \
1563 -o -name modules.builtin -o -name '.tmp_*.o.*' \
1564 -o -name '*.c.[012]*.*' \
1566 -o -name '*.gcno' \) -type f -print | xargs rm -f
1568 # Generate tags for editors
1569 # ---------------------------------------------------------------------------
1570 quiet_cmd_tags = GEN $@
1571 cmd_tags = $(CONFIG_SHELL) $(srctree)/scripts/tags.sh $@
1573 tags TAGS cscope gtags: FORCE
1576 # Scripts to check various things for consistency
1577 # ---------------------------------------------------------------------------
1579 PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1582 find $(srctree)/* $(RCS_FIND_IGNORE) \
1583 -name '*.[hcS]' -type f -print | sort \
1584 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1587 find $(srctree)/* $(RCS_FIND_IGNORE) \
1588 -name '*.[hcS]' -type f -print | sort \
1589 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1592 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/$@
1595 $(PERL) $(srctree)/scripts/namespace.pl
1598 $(PERL) $(srctree)/scripts/export_report.pl
1600 endif #ifeq ($(config-targets),1)
1601 endif #ifeq ($(mixed-targets),1)
1603 PHONY += checkstack kernelrelease kernelversion image_name
1605 # UML needs a little special treatment here. It wants to use the host
1606 # toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
1607 # else wants $(ARCH), including people doing cross-builds, which means
1608 # that $(SUBARCH) doesn't work here.
1610 CHECKSTACK_ARCH := $(SUBARCH)
1612 CHECKSTACK_ARCH := $(ARCH)
1615 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1616 $(PERL) $(src)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1619 @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1622 @echo $(KERNELVERSION)
1625 @echo $(KBUILD_IMAGE)
1627 # Clear a bunch of variables before executing the submake
1629 $(Q)mkdir -p $(objtree)/tools
1630 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(filter --j% -j,$(MAKEFLAGS))" O=$(shell cd $(objtree) && /bin/pwd) subdir=tools -C $(src)/tools/
1633 $(Q)mkdir -p $(objtree)/tools
1634 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(filter --j% -j,$(MAKEFLAGS))" O=$(shell cd $(objtree) && /bin/pwd) subdir=tools -C $(src)/tools/ $*
1637 # ---------------------------------------------------------------------------
1638 # Single targets are compatible with:
1639 # - build with mixed source and output
1640 # - build with separate output dir 'make O=...'
1641 # - external modules
1643 # target-dir => where to store outputfile
1644 # build-dir => directory in kernel source tree to use
1646 ifeq ($(KBUILD_EXTMOD),)
1647 build-dir = $(patsubst %/,%,$(dir $@))
1648 target-dir = $(dir $@)
1650 zap-slash=$(filter-out .,$(patsubst %/,%,$(dir $@)))
1651 build-dir = $(KBUILD_EXTMOD)$(if $(zap-slash),/$(zap-slash))
1652 target-dir = $(if $(KBUILD_EXTMOD),$(dir $<),$(dir $@))
1655 %.s: %.c prepare scripts FORCE
1656 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1657 %.i: %.c prepare scripts FORCE
1658 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1659 %.o: %.c prepare scripts FORCE
1660 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1661 %.lst: %.c prepare scripts FORCE
1662 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1663 %.s: %.S prepare scripts FORCE
1664 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1665 %.o: %.S prepare scripts FORCE
1666 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1667 %.symtypes: %.c prepare scripts FORCE
1668 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1669 %.ll: %.c prepare scripts FORCE
1670 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1673 /: prepare scripts FORCE
1675 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1676 $(build)=$(build-dir)
1677 # Make sure the latest headers are built for Documentation
1678 Documentation/ samples/: headers_install
1679 %/: prepare scripts FORCE
1681 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1682 $(build)=$(build-dir)
1683 %.ko: prepare scripts FORCE
1685 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1686 $(build)=$(build-dir) $(@:.ko=.o)
1687 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1689 # FIXME Should go into a make.lib or something
1690 # ===========================================================================
1692 quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN $(wildcard $(rm-dirs)))
1693 cmd_rmdirs = rm -rf $(rm-dirs)
1695 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
1696 cmd_rmfiles = rm -f $(rm-files)
1698 # Run depmod only if we have System.map and depmod is executable
1699 quiet_cmd_depmod = DEPMOD $(KERNELRELEASE)
1700 cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1701 $(KERNELRELEASE) "$(patsubst y,_,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX))"
1703 # Create temporary dir for module support files
1704 # clean it up only when building all modules
1705 cmd_crmodverdir = $(Q)mkdir -p $(MODVERDIR) \
1706 $(if $(KBUILD_MODULES),; rm -f $(MODVERDIR)/*)
1708 # read all saved command lines
1710 targets := $(wildcard $(sort $(targets)))
1711 cmd_files := $(wildcard .*.cmd $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
1713 ifneq ($(cmd_files),)
1714 $(cmd_files): ; # Do not try to update included dependency files
1715 include $(cmd_files)
1718 endif # skip-makefile
1723 # Declare the contents of the .PHONY variable as phony. We keep that
1724 # information in a variable so we can use it in if_changed and friends.