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 -Wno-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,)
633 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
634 KBUILD_CFLAGS += $(call cc-option,-ffunction-sections,)
635 KBUILD_CFLAGS += $(call cc-option,-fdata-sections,)
638 ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
639 KBUILD_CFLAGS += -Os $(call cc-disable-warning,maybe-uninitialized,)
641 ifdef CONFIG_PROFILE_ALL_BRANCHES
642 KBUILD_CFLAGS += -O2 $(call cc-disable-warning,maybe-uninitialized,)
648 KBUILD_CFLAGS += $(call cc-ifversion, -lt, 0409, \
649 $(call cc-disable-warning,maybe-uninitialized,))
651 # Tell gcc to never replace conditional load with a non-conditional one
652 KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
654 include scripts/Makefile.gcc-plugins
656 ifdef CONFIG_READABLE_ASM
657 # Disable optimizations that make assembler listings hard to read.
658 # reorder blocks reorders the control in the function
659 # ipa clone creates specialized cloned functions
660 # partial inlining inlines only parts of functions
661 KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
662 $(call cc-option,-fno-ipa-cp-clone,) \
663 $(call cc-option,-fno-partial-inlining)
666 ifneq ($(CONFIG_FRAME_WARN),0)
667 KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
670 # This selects the stack protector compiler flag. Testing it is delayed
671 # until after .config has been reprocessed, in the prepare-compiler-check
673 ifdef CONFIG_CC_STACKPROTECTOR_REGULAR
674 stackp-flag := -fstack-protector
675 stackp-name := REGULAR
677 ifdef CONFIG_CC_STACKPROTECTOR_STRONG
678 stackp-flag := -fstack-protector-strong
679 stackp-name := STRONG
681 # Force off for distro compilers that enable stack protector by default.
682 stackp-flag := $(call cc-option, -fno-stack-protector)
685 # Find arch-specific stack protector compiler sanity-checking script.
686 ifdef CONFIG_CC_STACKPROTECTOR
687 stackp-path := $(srctree)/scripts/gcc-$(SRCARCH)_$(BITS)-has-stack-protector.sh
688 stackp-check := $(wildcard $(stackp-path))
690 KBUILD_CFLAGS += $(stackp-flag)
692 ifeq ($(cc-name),clang)
693 KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
694 KBUILD_CPPFLAGS += $(call cc-option,-Wno-unknown-warning-option,)
695 KBUILD_CFLAGS += $(call cc-disable-warning, unused-variable)
696 KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier)
697 KBUILD_CFLAGS += $(call cc-disable-warning, gnu)
698 # Quiet clang warning: comparison of unsigned expression < 0 is always false
699 KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare)
700 # CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
701 # source of a reference will be _MergedGlobals and not on of the whitelisted names.
702 # See modpost pattern 2
703 KBUILD_CFLAGS += $(call cc-option, -mno-global-merge,)
704 KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior)
707 # These warnings generated too much noise in a regular build.
708 # Use make W=1 to enable them (see scripts/Makefile.build)
709 KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
710 KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
713 ifdef CONFIG_FRAME_POINTER
714 KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
716 # Some targets (ARM with Thumb2, for example), can't be built with frame
717 # pointers. For those, we don't have FUNCTION_TRACER automatically
718 # select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
719 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
720 # -fomit-frame-pointer with FUNCTION_TRACER.
721 ifndef CONFIG_FUNCTION_TRACER
722 KBUILD_CFLAGS += -fomit-frame-pointer
726 KBUILD_CFLAGS += $(call cc-option, -fno-var-tracking-assignments)
728 ifdef CONFIG_DEBUG_INFO
729 ifdef CONFIG_DEBUG_INFO_SPLIT
730 KBUILD_CFLAGS += $(call cc-option, -gsplit-dwarf, -g)
734 KBUILD_AFLAGS += -Wa,-gdwarf-2
736 ifdef CONFIG_DEBUG_INFO_DWARF4
737 KBUILD_CFLAGS += $(call cc-option, -gdwarf-4,)
740 ifdef CONFIG_DEBUG_INFO_REDUCED
741 KBUILD_CFLAGS += $(call cc-option, -femit-struct-debug-baseonly) \
742 $(call cc-option,-fno-var-tracking)
745 ifdef CONFIG_FUNCTION_TRACER
746 ifndef CC_FLAGS_FTRACE
747 CC_FLAGS_FTRACE := -pg
749 export CC_FLAGS_FTRACE
750 ifdef CONFIG_HAVE_FENTRY
751 CC_USING_FENTRY := $(call cc-option, -mfentry -DCC_USING_FENTRY)
753 KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_USING_FENTRY)
754 KBUILD_AFLAGS += $(CC_USING_FENTRY)
755 ifdef CONFIG_DYNAMIC_FTRACE
756 ifdef CONFIG_HAVE_C_RECORDMCOUNT
757 BUILD_C_RECORDMCOUNT := y
758 export BUILD_C_RECORDMCOUNT
763 # We trigger additional mismatches with less inlining
764 ifdef CONFIG_DEBUG_SECTION_MISMATCH
765 KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
768 # arch Makefile may override CC so keep this after arch Makefile is included
769 NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
770 CHECKFLAGS += $(NOSTDINC_FLAGS)
772 # warn about C99 declaration after statement
773 KBUILD_CFLAGS += $(call cc-option,-Wdeclaration-after-statement,)
775 # disable pointer signed / unsigned warnings in gcc 4.0
776 KBUILD_CFLAGS += $(call cc-disable-warning, pointer-sign)
778 # disable invalid "can't wrap" optimizations for signed / pointers
779 KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow)
781 # conserve stack if available
782 KBUILD_CFLAGS += $(call cc-option,-fconserve-stack)
784 # disallow errors like 'EXPORT_GPL(foo);' with missing header
785 KBUILD_CFLAGS += $(call cc-option,-Werror=implicit-int)
787 # require functions to have arguments in prototypes, not empty 'int foo()'
788 KBUILD_CFLAGS += $(call cc-option,-Werror=strict-prototypes)
790 # Prohibit date/time macros, which would make the build non-deterministic
791 KBUILD_CFLAGS += $(call cc-option,-Werror=date-time)
793 # enforce correct pointer usage
794 KBUILD_CFLAGS += $(call cc-option,-Werror=incompatible-pointer-types)
796 # use the deterministic mode of AR if available
797 KBUILD_ARFLAGS := $(call ar-option,D)
799 # check for 'asm goto'
800 ifeq ($(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC) $(KBUILD_CFLAGS)), y)
801 KBUILD_CFLAGS += -DCC_HAVE_ASM_GOTO
802 KBUILD_AFLAGS += -DCC_HAVE_ASM_GOTO
805 include scripts/Makefile.kasan
806 include scripts/Makefile.extrawarn
807 include scripts/Makefile.ubsan
809 # Add any arch overrides and user supplied CPPFLAGS, AFLAGS and CFLAGS as the
811 KBUILD_CPPFLAGS += $(ARCH_CPPFLAGS) $(KCPPFLAGS)
812 KBUILD_AFLAGS += $(ARCH_AFLAGS) $(KAFLAGS)
813 KBUILD_CFLAGS += $(ARCH_CFLAGS) $(KCFLAGS)
815 # Use --build-id when available.
816 LDFLAGS_BUILD_ID = $(patsubst -Wl$(comma)%,%,\
817 $(call cc-ldoption, -Wl$(comma)--build-id,))
818 KBUILD_LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID)
819 LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)
821 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
822 LDFLAGS_vmlinux += $(call ld-option, --gc-sections,)
825 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
826 LDFLAGS_vmlinux += $(call ld-option, -X,)
829 # Default kernel image to build when no specific target is given.
830 # KBUILD_IMAGE may be overruled on the command line or
831 # set in the environment
832 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
834 export KBUILD_IMAGE ?= vmlinux
837 # INSTALL_PATH specifies where to place the updated kernel and system map
838 # images. Default is /boot, but you can set it to other values
839 export INSTALL_PATH ?= /boot
842 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
843 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
844 # an argument if needed. Otherwise it defaults to the kernel install path
846 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
849 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
850 # relocations required by build roots. This is not defined in the
851 # makefile but the argument can be passed to make if needed.
854 MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
858 # INSTALL_MOD_STRIP, if defined, will cause modules to be
859 # stripped after they are installed. If INSTALL_MOD_STRIP is '1', then
860 # the default option --strip-debug will be used. Otherwise,
861 # INSTALL_MOD_STRIP value will be used as the options to the strip command.
863 ifdef INSTALL_MOD_STRIP
864 ifeq ($(INSTALL_MOD_STRIP),1)
865 mod_strip_cmd = $(STRIP) --strip-debug
867 mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
868 endif # INSTALL_MOD_STRIP=1
871 endif # INSTALL_MOD_STRIP
874 # CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
875 # after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
876 # or CONFIG_MODULE_COMPRESS_XZ.
878 mod_compress_cmd = true
879 ifdef CONFIG_MODULE_COMPRESS
880 ifdef CONFIG_MODULE_COMPRESS_GZIP
881 mod_compress_cmd = gzip -n -f
882 endif # CONFIG_MODULE_COMPRESS_GZIP
883 ifdef CONFIG_MODULE_COMPRESS_XZ
884 mod_compress_cmd = xz -f
885 endif # CONFIG_MODULE_COMPRESS_XZ
886 endif # CONFIG_MODULE_COMPRESS
887 export mod_compress_cmd
889 # Select initial ramdisk compression format, default is gzip(1).
890 # This shall be used by the dracut(8) tool while creating an initramfs image.
892 INITRD_COMPRESS-y := gzip
893 INITRD_COMPRESS-$(CONFIG_RD_BZIP2) := bzip2
894 INITRD_COMPRESS-$(CONFIG_RD_LZMA) := lzma
895 INITRD_COMPRESS-$(CONFIG_RD_XZ) := xz
896 INITRD_COMPRESS-$(CONFIG_RD_LZO) := lzo
897 INITRD_COMPRESS-$(CONFIG_RD_LZ4) := lz4
898 # do not export INITRD_COMPRESS, since we didn't actually
899 # choose a sane default compression above.
900 # export INITRD_COMPRESS := $(INITRD_COMPRESS-y)
902 ifdef CONFIG_MODULE_SIG_ALL
903 $(eval $(call config_filename,MODULE_SIG_KEY))
905 mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
912 ifeq ($(KBUILD_EXTMOD),)
913 core-y += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
915 vmlinux-dirs := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
916 $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
917 $(net-y) $(net-m) $(libs-y) $(libs-m) $(virt-y)))
919 vmlinux-alldirs := $(sort $(vmlinux-dirs) $(patsubst %/,%,$(filter %/, \
920 $(init-) $(core-) $(drivers-) $(net-) $(libs-) $(virt-))))
922 init-y := $(patsubst %/, %/built-in.o, $(init-y))
923 core-y := $(patsubst %/, %/built-in.o, $(core-y))
924 drivers-y := $(patsubst %/, %/built-in.o, $(drivers-y))
925 net-y := $(patsubst %/, %/built-in.o, $(net-y))
926 libs-y1 := $(patsubst %/, %/lib.a, $(libs-y))
927 libs-y2 := $(patsubst %/, %/built-in.o, $(libs-y))
928 libs-y := $(libs-y1) $(libs-y2)
929 virt-y := $(patsubst %/, %/built-in.o, $(virt-y))
931 # Externally visible symbols (used by link-vmlinux.sh)
932 export KBUILD_VMLINUX_INIT := $(head-y) $(init-y)
933 export KBUILD_VMLINUX_MAIN := $(core-y) $(libs-y) $(drivers-y) $(net-y) $(virt-y)
934 export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
935 export LDFLAGS_vmlinux
936 # used by scripts/pacmage/Makefile
937 export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) arch Documentation include samples scripts tools)
939 vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_INIT) $(KBUILD_VMLINUX_MAIN)
941 # Include targets which we want to execute sequentially if the rest of the
942 # kernel build went well. If CONFIG_TRIM_UNUSED_KSYMS is set, this might be
943 # evaluated more than once.
944 PHONY += vmlinux_prereq
945 vmlinux_prereq: $(vmlinux-deps) FORCE
946 ifdef CONFIG_HEADERS_CHECK
947 $(Q)$(MAKE) -f $(srctree)/Makefile headers_check
949 ifdef CONFIG_GDB_SCRIPTS
950 $(Q)ln -fsn `cd $(srctree) && /bin/pwd`/scripts/gdb/vmlinux-gdb.py
952 ifdef CONFIG_TRIM_UNUSED_KSYMS
953 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
954 "$(MAKE) -f $(srctree)/Makefile vmlinux"
957 # standalone target for easier testing
958 include/generated/autoksyms.h: FORCE
959 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh true
961 ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
963 # Final link of vmlinux with optional arch pass after final link
965 $(CONFIG_SHELL) $< $(LD) $(LDFLAGS) $(LDFLAGS_vmlinux) ; \
966 $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
968 vmlinux: scripts/link-vmlinux.sh vmlinux_prereq $(vmlinux-deps) FORCE
969 +$(call if_changed,link-vmlinux)
971 # Build samples along the rest of the kernel
973 vmlinux-dirs += samples
976 # The actual objects are generated when descending,
977 # make sure no implicit rule kicks in
978 $(sort $(vmlinux-deps)): $(vmlinux-dirs) ;
980 # Handle descending into subdirectories listed in $(vmlinux-dirs)
981 # Preset locale variables to speed up the build process. Limit locale
982 # tweaks to this spot to avoid wrong language settings when running
983 # make menuconfig etc.
984 # Error messages still appears in the original language
986 PHONY += $(vmlinux-dirs)
987 $(vmlinux-dirs): prepare scripts
988 $(Q)$(MAKE) $(build)=$@
990 define filechk_kernel.release
991 echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
994 # Store (new) KERNELRELEASE string in include/config/kernel.release
995 include/config/kernel.release: include/config/auto.conf FORCE
996 $(call filechk,kernel.release)
999 # Things we need to do before we recursively start building the kernel
1000 # or the modules are listed in "prepare".
1001 # A multi level approach is used. prepareN is processed before prepareN-1.
1002 # archprepare is used in arch Makefiles and when processed asm symlink,
1003 # version.h and scripts_basic is processed / created.
1005 # Listed in dependency order
1006 PHONY += prepare archprepare prepare0 prepare1 prepare2 prepare3
1008 # prepare3 is used to check if we are building in a separate output directory,
1010 # 1) Check that make has not been executed in the kernel src $(srctree)
1011 prepare3: include/config/kernel.release
1012 ifneq ($(KBUILD_SRC),)
1013 @$(kecho) ' Using $(srctree) as source for kernel'
1014 $(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \
1015 echo >&2 " $(srctree) is not clean, please run 'make mrproper'"; \
1016 echo >&2 " in the '$(srctree)' directory.";\
1021 # prepare2 creates a makefile if using a separate output directory.
1022 # From this point forward, .config has been reprocessed, so any rules
1023 # that need to depend on updated CONFIG_* values can be checked here.
1024 prepare2: prepare3 prepare-compiler-check outputmakefile asm-generic
1026 prepare1: prepare2 $(version_h) include/generated/utsrelease.h \
1027 include/config/auto.conf
1030 archprepare: archheaders archscripts prepare1 scripts_basic
1032 prepare0: archprepare gcc-plugins
1033 $(Q)$(MAKE) $(build)=.
1035 # All the preparing..
1036 prepare: prepare0 prepare-objtool
1038 ifdef CONFIG_STACK_VALIDATION
1039 has_libelf := $(call try-run,\
1040 echo "int main() {}" | $(HOSTCC) -xc -o /dev/null -lelf -,1,0)
1041 ifeq ($(has_libelf),1)
1042 objtool_target := tools/objtool FORCE
1044 $(warning "Cannot use CONFIG_STACK_VALIDATION, please install libelf-dev, libelf-devel or elfutils-libelf-devel")
1045 SKIP_STACK_VALIDATION := 1
1046 export SKIP_STACK_VALIDATION
1050 PHONY += prepare-objtool
1051 prepare-objtool: $(objtool_target)
1053 # Check for CONFIG flags that require compiler support. Abort the build
1054 # after .config has been processed, but before the kernel build starts.
1056 # For security-sensitive CONFIG options, we don't want to fallback and/or
1057 # silently change which compiler flags will be used, since that leads to
1058 # producing kernels with different security feature characteristics
1059 # depending on the compiler used. (For example, "But I selected
1060 # CC_STACKPROTECTOR_STRONG! Why did it build with _REGULAR?!")
1061 PHONY += prepare-compiler-check
1062 prepare-compiler-check: FORCE
1063 # Make sure compiler supports requested stack protector flag.
1065 ifeq ($(call cc-option, $(stackp-flag)),)
1066 @echo Cannot use CONFIG_CC_STACKPROTECTOR_$(stackp-name): \
1067 $(stackp-flag) not supported by compiler >&2 && exit 1
1070 # Make sure compiler does not have buggy stack-protector support.
1072 ifneq ($(shell $(CONFIG_SHELL) $(stackp-check) $(CC) $(KBUILD_CPPFLAGS) $(biarch)),y)
1073 @echo Cannot use CONFIG_CC_STACKPROTECTOR_$(stackp-name): \
1074 $(stackp-flag) available but compiler is broken >&2 && exit 1
1079 # Generate some files
1080 # ---------------------------------------------------------------------------
1082 # KERNELRELEASE can change from a few different places, meaning version.h
1083 # needs to be updated, so this check is forced on all builds
1086 define filechk_utsrelease.h
1087 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1088 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1091 (echo \#define UTS_RELEASE \"$(KERNELRELEASE)\";)
1094 define filechk_version.h
1095 (echo \#define LINUX_VERSION_CODE $(shell \
1096 expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1097 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))';)
1100 $(version_h): $(srctree)/Makefile FORCE
1101 $(call filechk,version.h)
1102 $(Q)rm -f $(old_version_h)
1104 include/generated/utsrelease.h: include/config/kernel.release FORCE
1105 $(call filechk,utsrelease.h)
1109 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1110 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1112 # ---------------------------------------------------------------------------
1114 INSTALL_FW_PATH=$(INSTALL_MOD_PATH)/lib/firmware
1115 export INSTALL_FW_PATH
1117 PHONY += firmware_install
1119 @mkdir -p $(objtree)/firmware
1120 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_install
1122 # ---------------------------------------------------------------------------
1125 #Default location for installed headers
1126 export INSTALL_HDR_PATH = $(objtree)/usr
1128 # If we do an all arch process set dst to asm-$(hdr-arch)
1129 hdr-dst = $(if $(KBUILD_HEADERS), dst=include/asm-$(hdr-arch), dst=include/asm)
1131 PHONY += archheaders
1134 PHONY += archscripts
1138 __headers: $(version_h) scripts_basic asm-generic archheaders archscripts
1139 $(Q)$(MAKE) $(build)=scripts build_unifdef
1141 PHONY += headers_install_all
1142 headers_install_all:
1143 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh install
1145 PHONY += headers_install
1146 headers_install: __headers
1147 $(if $(wildcard $(srctree)/arch/$(hdr-arch)/include/uapi/asm/Kbuild),, \
1148 $(error Headers not exportable for the $(SRCARCH) architecture))
1149 $(Q)$(MAKE) $(hdr-inst)=include/uapi
1150 $(Q)$(MAKE) $(hdr-inst)=arch/$(hdr-arch)/include/uapi/asm $(hdr-dst)
1152 PHONY += headers_check_all
1153 headers_check_all: headers_install_all
1154 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh check
1156 PHONY += headers_check
1157 headers_check: headers_install
1158 $(Q)$(MAKE) $(hdr-inst)=include/uapi HDRCHECK=1
1159 $(Q)$(MAKE) $(hdr-inst)=arch/$(hdr-arch)/include/uapi/asm $(hdr-dst) HDRCHECK=1
1161 # ---------------------------------------------------------------------------
1166 $(Q)$(MAKE) -C tools/testing/selftests run_tests
1169 $(Q)$(MAKE) -C tools/testing/selftests clean
1171 PHONY += kselftest-merge
1173 $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1174 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/kconfig/merge_config.sh \
1175 -m $(objtree)/.config \
1176 $(srctree)/tools/testing/selftests/*/config
1177 +$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1179 # ---------------------------------------------------------------------------
1182 ifdef CONFIG_MODULES
1184 # By default, build modules as well
1190 # A module can be listed more than once in obj-m resulting in
1191 # duplicate lines in modules.order files. Those are removed
1192 # using awk while concatenating to the final file.
1195 modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux) modules.builtin
1196 $(Q)$(AWK) '!x[$$0]++' $(vmlinux-dirs:%=$(objtree)/%/modules.order) > $(objtree)/modules.order
1197 @$(kecho) ' Building modules, stage 2.';
1198 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1199 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_modbuild
1201 modules.builtin: $(vmlinux-dirs:%=%/modules.builtin)
1202 $(Q)$(AWK) '!x[$$0]++' $^ > $(objtree)/modules.builtin
1204 %/modules.builtin: include/config/auto.conf
1205 $(Q)$(MAKE) $(modbuiltin)=$*
1208 # Target to prepare building external modules
1209 PHONY += modules_prepare
1210 modules_prepare: prepare scripts
1212 # Target to install modules
1213 PHONY += modules_install
1214 modules_install: _modinst_ _modinst_post
1218 @rm -rf $(MODLIB)/kernel
1219 @rm -f $(MODLIB)/source
1220 @mkdir -p $(MODLIB)/kernel
1221 @ln -s `cd $(srctree) && /bin/pwd` $(MODLIB)/source
1222 @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
1223 rm -f $(MODLIB)/build ; \
1224 ln -s $(CURDIR) $(MODLIB)/build ; \
1226 @cp -f $(objtree)/modules.order $(MODLIB)/
1227 @cp -f $(objtree)/modules.builtin $(MODLIB)/
1228 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1230 # This depmod is only for convenience to give the initial
1231 # boot a modules.dep even before / is mounted read-write. However the
1232 # boot script depmod is the master version.
1233 PHONY += _modinst_post
1234 _modinst_post: _modinst_
1235 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_modinst
1238 ifeq ($(CONFIG_MODULE_SIG), y)
1239 PHONY += modules_sign
1241 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1244 else # CONFIG_MODULES
1246 # Modules not configured
1247 # ---------------------------------------------------------------------------
1249 PHONY += modules modules_install
1250 modules modules_install:
1252 @echo >&2 "The present kernel configuration has modules disabled."
1253 @echo >&2 "Type 'make config' and enable loadable module support."
1254 @echo >&2 "Then build a kernel with module support enabled."
1258 endif # CONFIG_MODULES
1261 # Cleaning is done on three levels.
1262 # make clean Delete most generated files
1263 # Leave enough to build external modules
1264 # make mrproper Delete the current configuration, and all generated files
1265 # make distclean Remove editor backup files, patch leftover files and the like
1267 # Directories & files removed with 'make clean'
1268 CLEAN_DIRS += $(MODVERDIR)
1270 # Directories & files removed with 'make mrproper'
1271 MRPROPER_DIRS += include/config usr/include include/generated \
1272 arch/*/include/generated .tmp_objdiff
1273 MRPROPER_FILES += .config .config.old .version .old_version \
1274 Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS \
1275 signing_key.pem signing_key.priv signing_key.x509 \
1276 x509.genkey extra_certificates signing_key.x509.keyid \
1277 signing_key.x509.signer vmlinux-gdb.py
1279 # clean - Delete most, but leave enough to build external modules
1281 clean: rm-dirs := $(CLEAN_DIRS)
1282 clean: rm-files := $(CLEAN_FILES)
1283 clean-dirs := $(addprefix _clean_, . $(vmlinux-alldirs) Documentation samples)
1285 PHONY += $(clean-dirs) clean archclean vmlinuxclean
1287 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1290 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1291 $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1293 clean: archclean vmlinuxclean
1295 # mrproper - Delete all generated files, including .config
1297 mrproper: rm-dirs := $(wildcard $(MRPROPER_DIRS))
1298 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1299 mrproper-dirs := $(addprefix _mrproper_,Documentation/DocBook scripts)
1301 PHONY += $(mrproper-dirs) mrproper archmrproper
1303 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1305 mrproper: clean archmrproper $(mrproper-dirs)
1314 @find $(srctree) $(RCS_FIND_IGNORE) \
1315 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1316 -o -name '*.bak' -o -name '#*#' -o -name '.*.orig' \
1317 -o -name '.*.rej' -o -name '*%' -o -name 'core' \) \
1318 -type f -print | xargs rm -f
1321 # Packaging of the kernel to various formats
1322 # ---------------------------------------------------------------------------
1323 # rpm target kept for backward compatibility
1324 package-dir := scripts/package
1327 $(Q)$(MAKE) $(build)=$(package-dir) $@
1328 %pkg: include/config/kernel.release FORCE
1329 $(Q)$(MAKE) $(build)=$(package-dir) $@
1330 rpm: include/config/kernel.release FORCE
1331 $(Q)$(MAKE) $(build)=$(package-dir) $@
1334 # Brief documentation of the typical targets used
1335 # ---------------------------------------------------------------------------
1337 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1338 boards := $(sort $(notdir $(boards)))
1339 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1340 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1344 @echo 'Cleaning targets:'
1345 @echo ' clean - Remove most generated files but keep the config and'
1346 @echo ' enough build support to build external modules'
1347 @echo ' mrproper - Remove all generated files + config + various backup files'
1348 @echo ' distclean - mrproper + remove editor backup and patch files'
1350 @echo 'Configuration targets:'
1351 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1353 @echo 'Other generic targets:'
1354 @echo ' all - Build all targets marked with [*]'
1355 @echo '* vmlinux - Build the bare kernel'
1356 @echo '* modules - Build all modules'
1357 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1358 @echo ' firmware_install- Install all firmware to INSTALL_FW_PATH'
1359 @echo ' (default: $$(INSTALL_MOD_PATH)/lib/firmware)'
1360 @echo ' dir/ - Build all files in dir and below'
1361 @echo ' dir/file.[ois] - Build specified target only'
1362 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1363 @echo ' (requires a recent binutils and recent build (System.map))'
1364 @echo ' dir/file.ko - Build module including final link'
1365 @echo ' modules_prepare - Set up for building external modules'
1366 @echo ' tags/TAGS - Generate tags file for editors'
1367 @echo ' cscope - Generate cscope index'
1368 @echo ' gtags - Generate GNU GLOBAL index'
1369 @echo ' kernelrelease - Output the release version string (use with make -s)'
1370 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1371 @echo ' image_name - Output the image name (use with make -s)'
1372 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1373 echo ' (default: $(INSTALL_HDR_PATH))'; \
1375 @echo 'Static analysers'
1376 @echo ' checkstack - Generate a list of stack hogs'
1377 @echo ' namespacecheck - Name space analysis on compiled kernel'
1378 @echo ' versioncheck - Sanity check on version.h usage'
1379 @echo ' includecheck - Check for duplicate included header files'
1380 @echo ' export_report - List the usages of all exported symbols'
1381 @echo ' headers_check - Sanity check on exported headers'
1382 @echo ' headerdep - Detect inclusion cycles in headers'
1383 @$(MAKE) -f $(srctree)/scripts/Makefile.help checker-help
1385 @echo 'Kernel selftest'
1386 @echo ' kselftest - Build and run kernel selftest (run as root)'
1387 @echo ' Build, install, and boot kernel before'
1388 @echo ' running kselftest on it'
1389 @echo ' kselftest-clean - Remove all generated kselftest files'
1390 @echo ' kselftest-merge - Merge all the config dependencies of kselftest to existed'
1393 @echo 'Kernel packaging:'
1394 @$(MAKE) $(build)=$(package-dir) help
1396 @echo 'Documentation targets:'
1397 @$(MAKE) -f $(srctree)/Documentation/Makefile.sphinx dochelp
1399 @$(MAKE) -f $(srctree)/Documentation/DocBook/Makefile dochelp
1401 @echo 'Architecture specific targets ($(SRCARCH)):'
1402 @$(if $(archhelp),$(archhelp),\
1403 echo ' No architecture specific help defined for $(SRCARCH)')
1406 $(foreach b, $(boards), \
1407 printf " %-24s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1409 @$(if $(board-dirs), \
1410 $(foreach b, $(board-dirs), \
1411 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1412 printf " %-16s - Show all of the above\\n" help-boards; \
1415 @echo ' make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1416 @echo ' make V=2 [targets] 2 => give reason for rebuild of target'
1417 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1418 @echo ' make C=1 [targets] Check all c source with $$CHECK (sparse by default)'
1419 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1420 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1421 @echo ' make W=n [targets] Enable extra gcc checks, n=1,2,3 where'
1422 @echo ' 1: warnings which may be relevant and do not occur too often'
1423 @echo ' 2: warnings which occur quite often but may still be relevant'
1424 @echo ' 3: more obscure warnings, can most likely be ignored'
1425 @echo ' Multiple levels can be combined with W=12 or W=123'
1427 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1428 @echo 'For further info see the ./README file'
1431 help-board-dirs := $(addprefix help-,$(board-dirs))
1433 help-boards: $(help-board-dirs)
1435 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1437 $(help-board-dirs): help-%:
1438 @echo 'Architecture specific targets ($(SRCARCH) $*):'
1439 @$(if $(boards-per-dir), \
1440 $(foreach b, $(boards-per-dir), \
1441 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1445 # Documentation targets
1446 # ---------------------------------------------------------------------------
1447 DOC_TARGETS := xmldocs sgmldocs psdocs latexdocs pdfdocs htmldocs mandocs installmandocs epubdocs cleandocs
1448 PHONY += $(DOC_TARGETS)
1449 $(DOC_TARGETS): scripts_basic FORCE
1450 $(Q)$(MAKE) $(build)=scripts build_docproc build_check-lc_ctype
1451 $(Q)$(MAKE) $(build)=Documentation -f $(srctree)/Documentation/Makefile.sphinx $@
1452 $(Q)$(MAKE) $(build)=Documentation/DocBook $@
1454 else # KBUILD_EXTMOD
1457 # External module support.
1458 # When building external modules the kernel used as basis is considered
1459 # read-only, and no consistency checks are made and the make
1460 # system is not used on the basis kernel. If updates are required
1461 # in the basis kernel ordinary make commands (without M=...) must
1464 # The following are the only valid targets when building external
1466 # make M=dir clean Delete all automatically generated files
1467 # make M=dir modules Make all modules in specified dir
1468 # make M=dir Same as 'make M=dir modules'
1469 # make M=dir modules_install
1470 # Install the modules built in the module directory
1471 # Assumes install directory is already created
1473 # We are always building modules
1475 PHONY += crmodverdir
1479 PHONY += $(objtree)/Module.symvers
1480 $(objtree)/Module.symvers:
1481 @test -e $(objtree)/Module.symvers || ( \
1483 echo " WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1484 echo " is missing; modules will have no dependencies and modversions."; \
1487 module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
1488 PHONY += $(module-dirs) modules
1489 $(module-dirs): crmodverdir $(objtree)/Module.symvers
1490 $(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@)
1492 modules: $(module-dirs)
1493 @$(kecho) ' Building modules, stage 2.';
1494 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1496 PHONY += modules_install
1497 modules_install: _emodinst_ _emodinst_post
1499 install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1502 $(Q)mkdir -p $(MODLIB)/$(install-dir)
1503 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1505 PHONY += _emodinst_post
1506 _emodinst_post: _emodinst_
1509 clean-dirs := $(addprefix _clean_,$(KBUILD_EXTMOD))
1511 PHONY += $(clean-dirs) clean
1513 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1515 clean: rm-dirs := $(MODVERDIR)
1516 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers
1520 @echo ' Building external modules.'
1521 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1523 @echo ' modules - default target, build the module(s)'
1524 @echo ' modules_install - install the module'
1525 @echo ' clean - remove generated files in module directory only'
1529 PHONY += prepare scripts
1532 endif # KBUILD_EXTMOD
1534 clean: $(clean-dirs)
1537 @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1538 \( -name '*.[oas]' -o -name '*.ko' -o -name '.*.cmd' \
1542 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1543 -o -name '*.symtypes' -o -name 'modules.order' \
1544 -o -name modules.builtin -o -name '.tmp_*.o.*' \
1545 -o -name '*.c.[012]*.*' \
1546 -o -name '*.gcno' \) -type f -print | xargs rm -f
1548 # Generate tags for editors
1549 # ---------------------------------------------------------------------------
1550 quiet_cmd_tags = GEN $@
1551 cmd_tags = $(CONFIG_SHELL) $(srctree)/scripts/tags.sh $@
1553 tags TAGS cscope gtags: FORCE
1556 # Scripts to check various things for consistency
1557 # ---------------------------------------------------------------------------
1559 PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1562 find $(srctree)/* $(RCS_FIND_IGNORE) \
1563 -name '*.[hcS]' -type f -print | sort \
1564 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1567 find $(srctree)/* $(RCS_FIND_IGNORE) \
1568 -name '*.[hcS]' -type f -print | sort \
1569 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1572 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/$@
1575 $(PERL) $(srctree)/scripts/namespace.pl
1578 $(PERL) $(srctree)/scripts/export_report.pl
1580 endif #ifeq ($(config-targets),1)
1581 endif #ifeq ($(mixed-targets),1)
1583 PHONY += checkstack kernelrelease kernelversion image_name
1585 # UML needs a little special treatment here. It wants to use the host
1586 # toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
1587 # else wants $(ARCH), including people doing cross-builds, which means
1588 # that $(SUBARCH) doesn't work here.
1590 CHECKSTACK_ARCH := $(SUBARCH)
1592 CHECKSTACK_ARCH := $(ARCH)
1595 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1596 $(PERL) $(src)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1599 @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1602 @echo $(KERNELVERSION)
1605 @echo $(KBUILD_IMAGE)
1607 # Clear a bunch of variables before executing the submake
1609 $(Q)mkdir -p $(objtree)/tools
1610 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(filter --j% -j,$(MAKEFLAGS))" O=$(shell cd $(objtree) && /bin/pwd) subdir=tools -C $(src)/tools/
1613 $(Q)mkdir -p $(objtree)/tools
1614 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(filter --j% -j,$(MAKEFLAGS))" O=$(shell cd $(objtree) && /bin/pwd) subdir=tools -C $(src)/tools/ $*
1617 # ---------------------------------------------------------------------------
1618 # Single targets are compatible with:
1619 # - build with mixed source and output
1620 # - build with separate output dir 'make O=...'
1621 # - external modules
1623 # target-dir => where to store outputfile
1624 # build-dir => directory in kernel source tree to use
1626 ifeq ($(KBUILD_EXTMOD),)
1627 build-dir = $(patsubst %/,%,$(dir $@))
1628 target-dir = $(dir $@)
1630 zap-slash=$(filter-out .,$(patsubst %/,%,$(dir $@)))
1631 build-dir = $(KBUILD_EXTMOD)$(if $(zap-slash),/$(zap-slash))
1632 target-dir = $(if $(KBUILD_EXTMOD),$(dir $<),$(dir $@))
1635 %.s: %.c prepare scripts FORCE
1636 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1637 %.i: %.c prepare scripts FORCE
1638 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1639 %.o: %.c prepare scripts FORCE
1640 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1641 %.lst: %.c prepare scripts FORCE
1642 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1643 %.s: %.S prepare scripts FORCE
1644 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1645 %.o: %.S prepare scripts FORCE
1646 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1647 %.symtypes: %.c prepare scripts FORCE
1648 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1651 /: prepare scripts FORCE
1653 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1654 $(build)=$(build-dir)
1655 # Make sure the latest headers are built for Documentation
1656 Documentation/ samples/: headers_install
1657 %/: prepare scripts FORCE
1659 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1660 $(build)=$(build-dir)
1661 %.ko: prepare scripts FORCE
1663 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1664 $(build)=$(build-dir) $(@:.ko=.o)
1665 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1667 # FIXME Should go into a make.lib or something
1668 # ===========================================================================
1670 quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN $(wildcard $(rm-dirs)))
1671 cmd_rmdirs = rm -rf $(rm-dirs)
1673 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
1674 cmd_rmfiles = rm -f $(rm-files)
1676 # Run depmod only if we have System.map and depmod is executable
1677 quiet_cmd_depmod = DEPMOD $(KERNELRELEASE)
1678 cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1679 $(KERNELRELEASE) "$(patsubst y,_,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX))"
1681 # Create temporary dir for module support files
1682 # clean it up only when building all modules
1683 cmd_crmodverdir = $(Q)mkdir -p $(MODVERDIR) \
1684 $(if $(KBUILD_MODULES),; rm -f $(MODVERDIR)/*)
1686 # read all saved command lines
1688 targets := $(wildcard $(sort $(targets)))
1689 cmd_files := $(wildcard .*.cmd $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
1691 ifneq ($(cmd_files),)
1692 $(cmd_files): ; # Do not try to update included dependency files
1693 include $(cmd_files)
1696 endif # skip-makefile
1701 # Declare the contents of the .PHONY variable as phony. We keep that
1702 # information in a variable so we can use it in if_changed and friends.