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 # Do not use make's built-in rules and variables
14 # (this increases performance and avoids hard-to-debug behaviour);
17 # Avoid funny character set dependencies
21 export LC_COLLATE LC_NUMERIC
23 # Avoid interference with shell env settings
26 # We are using a recursive build, so we need to do a little thinking
27 # to get the ordering right.
29 # Most importantly: sub-Makefiles should only ever modify files in
30 # their own directory. If in some directory we have a dependency on
31 # a file in another dir (which doesn't happen often, but it's often
32 # unavoidable when linking the built-in.o targets which finally
33 # turn into vmlinux), we will call a sub make in that other dir, and
34 # after that we are sure that everything which is in that other dir
37 # The only cases where we need to modify files which have global
38 # effects are thus separated out and done before the recursive
39 # descending is started. They are now explicitly listed as the
43 # ---------------------------------------------------------------------------
45 # Normally, we echo the whole command before executing it. By making
46 # that echo $($(quiet)$(cmd)), we now have the possibility to set
47 # $(quiet) to choose other forms of output instead, e.g.
49 # quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
50 # cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
52 # If $(quiet) is empty, the whole command will be printed.
53 # If it is set to "quiet_", only the short version will be printed.
54 # If it is set to "silent_", nothing will be printed at all, since
55 # the variable $(silent_cmd_cc_o_c) doesn't exist.
57 # A simple variant is to prefix commands with $(Q) - that's useful
58 # for commands that shall be hidden in non-verbose mode.
62 # If KBUILD_VERBOSE equals 0 then the above command will be hidden.
63 # If KBUILD_VERBOSE equals 1 then the above command is displayed.
65 # To put more focus on warnings, be less verbose as default
66 # Use 'make V=1' to see the full commands
68 ifeq ("$(origin V)", "command line")
75 ifeq ($(KBUILD_VERBOSE),1)
83 # If the user is running make -s (silent mode), suppress echoing of
86 ifneq ($(filter 4.%,$(MAKE_VERSION)),) # make-4
87 ifneq ($(filter %s ,$(firstword x$(MAKEFLAGS))),)
91 ifneq ($(filter s% -s%,$(MAKEFLAGS)),)
96 export quiet Q KBUILD_VERBOSE
98 # kbuild supports saving output files in a separate directory.
99 # To locate output files in a separate directory two syntaxes are supported.
100 # In both cases the working directory must be the root of the kernel src.
102 # Use "make O=dir/to/store/output/files/"
104 # 2) Set KBUILD_OUTPUT
105 # Set the environment variable KBUILD_OUTPUT to point to the directory
106 # where the output files shall be placed.
107 # export KBUILD_OUTPUT=dir/to/store/output/files/
110 # The O= assignment takes precedence over the KBUILD_OUTPUT environment
113 # KBUILD_SRC is set on invocation of make in OBJ directory
114 # KBUILD_SRC is not intended to be used by the regular user (for now)
115 ifeq ($(KBUILD_SRC),)
117 # OK, Make called in directory where kernel src resides
118 # Do we want to locate output files in a separate directory?
119 ifeq ("$(origin O)", "command line")
120 KBUILD_OUTPUT := $(O)
123 # That's our default target when none is given on the command line
127 # Cancel implicit rules on top Makefile
128 $(CURDIR)/Makefile Makefile: ;
130 ifneq ($(KBUILD_OUTPUT),)
131 # Invoke a second make in the output directory, passing relevant variables
132 # check that the output directory actually exists
133 saved-output := $(KBUILD_OUTPUT)
134 KBUILD_OUTPUT := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) \
136 $(if $(KBUILD_OUTPUT),, \
137 $(error failed to create output directory "$(saved-output)"))
139 PHONY += $(MAKECMDGOALS) sub-make
141 $(filter-out _all sub-make $(CURDIR)/Makefile, $(MAKECMDGOALS)) _all: sub-make
145 $(Q)$(MAKE) -C $(KBUILD_OUTPUT) KBUILD_SRC=$(CURDIR) \
146 -f $(CURDIR)/Makefile $(filter-out _all sub-make,$(MAKECMDGOALS))
148 # Leave processing to above invocation of make
150 endif # ifneq ($(KBUILD_OUTPUT),)
151 endif # ifeq ($(KBUILD_SRC),)
153 # We process the rest of the Makefile if this is the final invocation of make
154 ifeq ($(skip-makefile),)
156 # Do not print "Entering directory ...",
157 # but we want to display it when entering to the output directory
158 # so that IDEs/editors are able to understand relative filenames.
159 MAKEFLAGS += --no-print-directory
161 # Call a source code checker (by default, "sparse") as part of the
164 # Use 'make C=1' to enable checking of only re-compiled files.
165 # Use 'make C=2' to enable checking of *all* source files, regardless
166 # of whether they are re-compiled or not.
168 # See the file "Documentation/sparse.txt" for more details, including
169 # where to get the "sparse" utility.
171 ifeq ("$(origin C)", "command line")
172 KBUILD_CHECKSRC = $(C)
174 ifndef KBUILD_CHECKSRC
178 # Use make M=dir to specify directory of external module to build
179 # Old syntax make ... SUBDIRS=$PWD is still supported
180 # Setting the environment variable KBUILD_EXTMOD take precedence
182 KBUILD_EXTMOD ?= $(SUBDIRS)
185 ifeq ("$(origin M)", "command line")
186 KBUILD_EXTMOD := $(M)
189 # If building an external module we do not care about the all: rule
190 # but instead _all depend on modules
192 ifeq ($(KBUILD_EXTMOD),)
198 ifeq ($(KBUILD_SRC),)
199 # building in the source tree
202 ifeq ($(KBUILD_SRC)/,$(dir $(CURDIR)))
203 # building in a subdirectory of the source tree
206 srctree := $(KBUILD_SRC)
213 VPATH := $(srctree)$(if $(KBUILD_EXTMOD),:$(KBUILD_EXTMOD))
215 export srctree objtree VPATH
218 # SUBARCH tells the usermode build what the underlying arch is. That is set
219 # first, and if a usermode build is happening, the "ARCH=um" on the command
220 # line overrides the setting of ARCH below. If a native build is happening,
221 # then ARCH is assigned, getting whatever value it gets normally, and
222 # SUBARCH is subsequently ignored.
224 SUBARCH := $(shell uname -m | sed -e s/i.86/x86/ -e s/x86_64/x86/ \
225 -e s/sun4u/sparc64/ \
226 -e s/arm.*/arm/ -e s/sa110/arm/ \
227 -e s/s390x/s390/ -e s/parisc64/parisc/ \
228 -e s/ppc.*/powerpc/ -e s/mips.*/mips/ \
229 -e s/sh[234].*/sh/ -e s/aarch64.*/arm64/ )
231 # Cross compiling and selecting different set of gcc/bin-utils
232 # ---------------------------------------------------------------------------
234 # When performing cross compilation for other architectures ARCH shall be set
235 # to the target architecture. (See arch/* for the possibilities).
236 # ARCH can be set during invocation of make:
238 # Another way is to have ARCH set in the environment.
239 # The default ARCH is the host where make is executed.
241 # CROSS_COMPILE specify the prefix used for all executables used
242 # during compilation. Only gcc and related bin-utils executables
243 # are prefixed with $(CROSS_COMPILE).
244 # CROSS_COMPILE can be set on the command line
245 # make CROSS_COMPILE=ia64-linux-
246 # Alternatively CROSS_COMPILE can be set in the environment.
247 # A third alternative is to store a setting in .config so that plain
248 # "make" in the configured kernel build directory always uses that.
249 # Default value for CROSS_COMPILE is not to prefix executables
250 # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
252 CROSS_COMPILE ?= $(CONFIG_CROSS_COMPILE:"%"=%)
254 # Architecture as present in compile.h
255 UTS_MACHINE := $(ARCH)
258 # Additional ARCH settings for x86
262 ifeq ($(ARCH),x86_64)
266 # Additional ARCH settings for sparc
267 ifeq ($(ARCH),sparc32)
270 ifeq ($(ARCH),sparc64)
274 # Additional ARCH settings for sh
279 # Additional ARCH settings for tile
280 ifeq ($(ARCH),tilepro)
283 ifeq ($(ARCH),tilegx)
287 # Where to locate arch specific headers
288 hdr-arch := $(SRCARCH)
290 KCONFIG_CONFIG ?= .config
291 export KCONFIG_CONFIG
293 # SHELL used by kbuild
294 CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
295 else if [ -x /bin/bash ]; then echo /bin/bash; \
296 else echo sh; fi ; fi)
300 HOSTCFLAGS = -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 -fomit-frame-pointer -std=gnu89
303 ifeq ($(shell $(HOSTCC) -v 2>&1 | grep -c "clang version"), 1)
304 HOSTCFLAGS += -Wno-unused-value -Wno-unused-parameter \
305 -Wno-missing-field-initializers -fno-delete-null-pointer-checks
308 # Decide whether to build built-in, modular, or both.
309 # Normally, just do built-in.
314 # If we have only "make modules", don't compile built-in objects.
315 # When we're building modules with modversions, we need to consider
316 # the built-in objects during the descend as well, in order to
317 # make sure the checksums are up to date before we record them.
319 ifeq ($(MAKECMDGOALS),modules)
320 KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
323 # If we have "make <whatever> modules", compile modules
324 # in addition to whatever we do anyway.
325 # Just "make" or "make all" shall build modules as well
327 ifneq ($(filter all _all modules,$(MAKECMDGOALS)),)
331 ifeq ($(MAKECMDGOALS),)
335 export KBUILD_MODULES KBUILD_BUILTIN
336 export KBUILD_CHECKSRC KBUILD_SRC KBUILD_EXTMOD
339 ifeq ($(shell $(CC) -v 2>&1 | grep -c "clang version"), 1)
347 # Look for make include files relative to root of kernel src
348 MAKEFLAGS += --include-dir=$(srctree)
350 # We need some generic definitions (do not try to remake the file).
351 $(srctree)/scripts/Kbuild.include: ;
352 include $(srctree)/scripts/Kbuild.include
354 # Make variables (CC, etc...)
355 AS = $(CROSS_COMPILE)as
356 LD = $(CROSS_COMPILE)ld
358 CC = $(CROSS_COMPILE)gcc
361 AR = $(CROSS_COMPILE)gcc-ar
363 AR = $(CROSS_COMPILE)ar
365 NM = $(CROSS_COMPILE)nm
366 STRIP = $(CROSS_COMPILE)strip
367 OBJCOPY = $(CROSS_COMPILE)objcopy
368 OBJDUMP = $(CROSS_COMPILE)objdump
370 GENKSYMS = scripts/genksyms/genksyms
371 INSTALLKERNEL := installkernel
372 DEPMOD = /sbin/depmod
377 CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
378 -Wbitwise -Wno-return-void $(CF)
384 CFLAGS_GCOV = -fprofile-arcs -ftest-coverage
387 # Use USERINCLUDE when you must reference the UAPI directories only.
389 -I$(srctree)/arch/$(hdr-arch)/include/uapi \
390 -Iarch/$(hdr-arch)/include/generated/uapi \
391 -I$(srctree)/include/uapi \
392 -Iinclude/generated/uapi \
393 -include $(srctree)/include/linux/kconfig.h
395 # Use LINUXINCLUDE when you must reference the include/ directory.
396 # Needed to be compatible with the O= option
398 -I$(srctree)/arch/$(hdr-arch)/include \
399 -Iarch/$(hdr-arch)/include/generated \
400 $(if $(KBUILD_SRC), -I$(srctree)/include) \
404 KBUILD_CPPFLAGS := -D__KERNEL__
406 KBUILD_CFLAGS := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
407 -fno-strict-aliasing -fno-common \
408 -Werror-implicit-function-declaration \
409 -Wno-format-security \
412 KBUILD_AFLAGS_KERNEL :=
413 KBUILD_CFLAGS_KERNEL :=
414 KBUILD_AFLAGS := -D__ASSEMBLY__
415 KBUILD_AFLAGS_MODULE := -DMODULE
416 KBUILD_CFLAGS_MODULE := -DMODULE
417 KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
419 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
420 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
421 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
423 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
424 export ARCH SRCARCH CONFIG_SHELL HOSTCC HOSTCFLAGS CROSS_COMPILE AS LD CC
425 export CPP AR NM STRIP OBJCOPY OBJDUMP LDFINAL
426 export MAKE AWK GENKSYMS INSTALLKERNEL PERL PYTHON UTS_MACHINE
427 export HOSTCXX HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
429 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS LDFLAGS
430 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE CFLAGS_GCOV
431 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
432 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
433 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
434 export KBUILD_ARFLAGS
437 # LTO gcc creates a lot of files in TMPDIR, and with /tmp as tmpfs
438 # it's easy to drive the machine OOM. Use the object directory
443 $(info setting TMPDIR=$(objtree) for LTO build)
447 # When compiling out-of-tree modules, put MODVERDIR in the module
448 # tree rather than in the kernel tree. The kernel tree might
450 export MODVERDIR := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_versions
452 # Files to ignore in find ... statements
454 export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o \
455 -name CVS -o -name .pc -o -name .hg -o -name .git \) \
457 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
458 --exclude CVS --exclude .pc --exclude .hg --exclude .git
460 # ===========================================================================
461 # Rules shared between *config targets and build targets
463 # Basic helpers built in scripts/
464 PHONY += scripts_basic
466 $(Q)$(MAKE) $(build)=scripts/basic
467 $(Q)rm -f .tmp_quiet_recordmcount
469 # To avoid any implicit rule to kick in, define an empty command.
470 scripts/basic/%: scripts_basic ;
472 PHONY += outputmakefile
473 # outputmakefile generates a Makefile in the output directory, if using a
474 # separate output directory. This allows convenient use of make in the
477 ifneq ($(KBUILD_SRC),)
478 $(Q)ln -fsn $(srctree) source
479 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile \
480 $(srctree) $(objtree) $(VERSION) $(PATCHLEVEL)
483 # Support for using generic headers in asm-generic
486 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
487 src=asm obj=arch/$(SRCARCH)/include/generated/asm
488 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
489 src=uapi/asm obj=arch/$(SRCARCH)/include/generated/uapi/asm
491 # To make sure we do not include .config for any of the *config targets
492 # catch them early, and hand them over to scripts/kconfig/Makefile
493 # It is allowed to specify more targets when calling make, including
494 # mixing *config targets and build targets.
495 # For example 'make oldconfig all'.
496 # Detect when mixed targets is specified, and make a second invocation
497 # of make so .config is not included in this case either (for *config).
499 version_h := include/generated/uapi/linux/version.h
500 old_version_h := include/linux/version.h
502 no-dot-config-targets := clean mrproper distclean \
503 cscope gtags TAGS tags help% %docs check% coccicheck \
504 $(version_h) headers_% archheaders archscripts \
505 kernelversion %src-pkg
511 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
512 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
517 ifeq ($(KBUILD_EXTMOD),)
518 ifneq ($(filter config %config,$(MAKECMDGOALS)),)
520 ifneq ($(words $(MAKECMDGOALS)),1)
526 ifeq ($(mixed-targets),1)
527 # ===========================================================================
528 # We're called with mixed targets (*config and build targets).
529 # Handle them one by one.
531 PHONY += $(MAKECMDGOALS) __build_one_by_one
533 $(filter-out __build_one_by_one, $(MAKECMDGOALS)): __build_one_by_one
538 for i in $(MAKECMDGOALS); do \
539 $(MAKE) -f $(srctree)/Makefile $$i; \
543 ifeq ($(config-targets),1)
544 # ===========================================================================
545 # *config targets only - make sure prerequisites are updated, and descend
546 # in scripts/kconfig to make the *config target
548 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
549 # KBUILD_DEFCONFIG may point out an alternative default configuration
550 # used for 'make defconfig'
551 include $(srctree)/arch/$(SRCARCH)/Makefile
552 export KBUILD_DEFCONFIG KBUILD_KCONFIG
554 config: scripts_basic outputmakefile FORCE
555 $(Q)$(MAKE) $(build)=scripts/kconfig $@
557 %config: scripts_basic outputmakefile FORCE
558 $(Q)$(MAKE) $(build)=scripts/kconfig $@
561 # ===========================================================================
562 # Build targets only - this includes vmlinux, arch specific targets, clean
563 # targets and others. In general all targets except *config targets.
565 ifeq ($(KBUILD_EXTMOD),)
566 # Additional helpers built in scripts/
567 # Carefully list dependencies so we do not try to build scripts twice
570 scripts: scripts_basic include/config/auto.conf include/config/tristate.conf \
572 $(Q)$(MAKE) $(build)=$(@)
574 # Objects we will link into vmlinux / subdirs we need to visit
576 drivers-y := drivers/ sound/ firmware/
580 endif # KBUILD_EXTMOD
582 ifeq ($(dot-config),1)
584 -include include/config/auto.conf
586 ifeq ($(KBUILD_EXTMOD),)
587 # Read in dependencies to all Kconfig* files, make sure to run
588 # oldconfig if changes are detected.
589 -include include/config/auto.conf.cmd
591 # To avoid any implicit rule to kick in, define an empty command
592 $(KCONFIG_CONFIG) include/config/auto.conf.cmd: ;
594 # If .config is newer than include/config/auto.conf, someone tinkered
595 # with it and forgot to run make oldconfig.
596 # if auto.conf.cmd is missing then we are probably in a cleaned tree so
597 # we execute the config step to be sure to catch updated Kconfig files
598 include/config/%.conf: $(KCONFIG_CONFIG) include/config/auto.conf.cmd
599 $(Q)$(MAKE) -f $(srctree)/Makefile silentoldconfig
601 # external modules needs include/generated/autoconf.h and include/config/auto.conf
602 # but do not care if they are up-to-date. Use auto.conf to trigger the test
603 PHONY += include/config/auto.conf
605 include/config/auto.conf:
606 $(Q)test -e include/generated/autoconf.h -a -e $@ || ( \
608 echo >&2 " ERROR: Kernel configuration is invalid."; \
609 echo >&2 " include/generated/autoconf.h or $@ are missing.";\
610 echo >&2 " Run 'make oldconfig && make prepare' on kernel src to fix it."; \
614 endif # KBUILD_EXTMOD
617 # Dummy target needed, because used as prerequisite
618 include/config/auto.conf: ;
619 endif # $(dot-config)
621 # The all: target is the default when no target is given on the
623 # This allow a user to issue only 'make' to build a kernel including modules
624 # Defaults to vmlinux, but the arch makefile usually adds further targets
627 include $(srctree)/arch/$(SRCARCH)/Makefile
629 KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,)
631 ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
632 KBUILD_CFLAGS += -Os $(call cc-disable-warning,maybe-uninitialized,)
637 # Tell gcc to never replace conditional load with a non-conditional one
638 KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
640 ifdef CONFIG_READABLE_ASM
641 # Disable optimizations that make assembler listings hard to read.
642 # reorder blocks reorders the control in the function
643 # ipa clone creates specialized cloned functions
644 # partial inlining inlines only parts of functions
645 KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
646 $(call cc-option,-fno-ipa-cp-clone,) \
647 $(call cc-option,-fno-partial-inlining)
650 ifneq ($(CONFIG_FRAME_WARN),0)
651 KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
654 # Handle stack protector mode.
656 # Since kbuild can potentially perform two passes (first with the old
657 # .config values and then with updated .config values), we cannot error out
658 # if a desired compiler option is unsupported. If we were to error, kbuild
659 # could never get to the second pass and actually notice that we changed
660 # the option to something that was supported.
662 # Additionally, we don't want to fallback and/or silently change which compiler
663 # flags will be used, since that leads to producing kernels with different
664 # security feature characteristics depending on the compiler used. ("But I
665 # selected CC_STACKPROTECTOR_STRONG! Why did it build with _REGULAR?!")
667 # The middle ground is to warn here so that the failed option is obvious, but
668 # to let the build fail with bad compiler flags so that we can't produce a
669 # kernel when there is a CONFIG and compiler mismatch.
671 ifdef CONFIG_CC_STACKPROTECTOR_REGULAR
672 stackp-flag := -fstack-protector
673 ifeq ($(call cc-option, $(stackp-flag)),)
674 $(warning Cannot use CONFIG_CC_STACKPROTECTOR_REGULAR: \
675 -fstack-protector not supported by compiler)
678 ifdef CONFIG_CC_STACKPROTECTOR_STRONG
679 stackp-flag := -fstack-protector-strong
680 ifeq ($(call cc-option, $(stackp-flag)),)
681 $(warning Cannot use CONFIG_CC_STACKPROTECTOR_STRONG: \
682 -fstack-protector-strong not supported by compiler)
685 # Force off for distro compilers that enable stack protector by default.
686 stackp-flag := $(call cc-option, -fno-stack-protector)
689 KBUILD_CFLAGS += $(stackp-flag)
691 ifeq ($(COMPILER),clang)
692 KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
693 KBUILD_CPPFLAGS += $(call cc-option,-Wno-unknown-warning-option,)
694 KBUILD_CFLAGS += $(call cc-disable-warning, unused-variable)
695 KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier)
696 KBUILD_CFLAGS += $(call cc-disable-warning, gnu)
697 # Quiet clang warning: comparison of unsigned expression < 0 is always false
698 KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare)
699 # CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
700 # source of a reference will be _MergedGlobals and not on of the whitelisted names.
701 # See modpost pattern 2
702 KBUILD_CFLAGS += $(call cc-option, -mno-global-merge,)
703 KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior)
706 # This warning generated too much noise in a regular build.
707 # Use make W=1 to enable this warning (see scripts/Makefile.build)
708 KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
711 ifdef CONFIG_FRAME_POINTER
712 KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
714 # Some targets (ARM with Thumb2, for example), can't be built with frame
715 # pointers. For those, we don't have FUNCTION_TRACER automatically
716 # select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
717 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
718 # -fomit-frame-pointer with FUNCTION_TRACER.
719 ifndef CONFIG_FUNCTION_TRACER
720 KBUILD_CFLAGS += -fomit-frame-pointer
724 KBUILD_CFLAGS += $(call cc-option, -fno-var-tracking-assignments)
726 ifdef CONFIG_DEBUG_INFO
727 ifdef CONFIG_DEBUG_INFO_SPLIT
728 KBUILD_CFLAGS += $(call cc-option, -gsplit-dwarf, -g)
732 KBUILD_AFLAGS += -Wa,-gdwarf-2
734 ifdef CONFIG_DEBUG_INFO_DWARF4
735 KBUILD_CFLAGS += $(call cc-option, -gdwarf-4,)
738 ifdef CONFIG_DEBUG_INFO_REDUCED
739 KBUILD_CFLAGS += $(call cc-option, -femit-struct-debug-baseonly) \
740 $(call cc-option,-fno-var-tracking)
743 ifdef CONFIG_FUNCTION_TRACER
744 ifdef CONFIG_HAVE_FENTRY
745 CC_USING_FENTRY := $(call cc-option, -mfentry -DCC_USING_FENTRY)
747 KBUILD_CFLAGS += -pg $(CC_USING_FENTRY)
748 KBUILD_AFLAGS += $(CC_USING_FENTRY)
749 ifdef CONFIG_DYNAMIC_FTRACE
750 ifdef CONFIG_HAVE_C_RECORDMCOUNT
751 BUILD_C_RECORDMCOUNT := y
752 export BUILD_C_RECORDMCOUNT
757 # We trigger additional mismatches with less inlining
758 ifdef CONFIG_DEBUG_SECTION_MISMATCH
759 KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
762 # arch Makefile may override CC so keep this after arch Makefile is included
763 NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
764 CHECKFLAGS += $(NOSTDINC_FLAGS)
766 # warn about C99 declaration after statement
767 KBUILD_CFLAGS += $(call cc-option,-Wdeclaration-after-statement,)
769 # disable pointer signed / unsigned warnings in gcc 4.0
770 KBUILD_CFLAGS += $(call cc-disable-warning, pointer-sign)
772 # disable invalid "can't wrap" optimizations for signed / pointers
773 KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow)
775 # conserve stack if available
776 KBUILD_CFLAGS += $(call cc-option,-fconserve-stack)
778 # disallow errors like 'EXPORT_GPL(foo);' with missing header
779 KBUILD_CFLAGS += $(call cc-option,-Werror=implicit-int)
781 # require functions to have arguments in prototypes, not empty 'int foo()'
782 KBUILD_CFLAGS += $(call cc-option,-Werror=strict-prototypes)
784 # Prohibit date/time macros, which would make the build non-deterministic
785 KBUILD_CFLAGS += $(call cc-option,-Werror=date-time)
787 # use the deterministic mode of AR if available
788 KBUILD_ARFLAGS := $(call ar-option,D)
790 # check for 'asm goto'
791 ifeq ($(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC)), y)
792 KBUILD_CFLAGS += -DCC_HAVE_ASM_GOTO
795 include $(srctree)/scripts/Makefile.extrawarn
796 include ${srctree}/scripts/Makefile.lto
798 # Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
799 KBUILD_CPPFLAGS += $(KCPPFLAGS)
800 KBUILD_AFLAGS += $(KAFLAGS)
801 KBUILD_CFLAGS += $(KCFLAGS)
803 # Use --build-id when available.
804 LDFLAGS_BUILD_ID = $(patsubst -Wl$(comma)%,%,\
805 $(call cc-ldoption, -Wl$(comma)--build-id,))
806 KBUILD_LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID)
807 LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)
809 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
810 LDFLAGS_vmlinux += $(call ld-option, -X,)
813 # Default kernel image to build when no specific target is given.
814 # KBUILD_IMAGE may be overruled on the command line or
815 # set in the environment
816 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
818 export KBUILD_IMAGE ?= vmlinux
821 # INSTALL_PATH specifies where to place the updated kernel and system map
822 # images. Default is /boot, but you can set it to other values
823 export INSTALL_PATH ?= /boot
826 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
827 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
828 # an argument if needed. Otherwise it defaults to the kernel install path
830 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
833 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
834 # relocations required by build roots. This is not defined in the
835 # makefile but the argument can be passed to make if needed.
838 MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
842 # INSTALL_MOD_STRIP, if defined, will cause modules to be
843 # stripped after they are installed. If INSTALL_MOD_STRIP is '1', then
844 # the default option --strip-debug will be used. Otherwise,
845 # INSTALL_MOD_STRIP value will be used as the options to the strip command.
847 ifdef INSTALL_MOD_STRIP
848 ifeq ($(INSTALL_MOD_STRIP),1)
849 mod_strip_cmd = $(STRIP) --strip-debug
851 mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
852 endif # INSTALL_MOD_STRIP=1
855 endif # INSTALL_MOD_STRIP
858 # CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
859 # after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
860 # or CONFIG_MODULE_COMPRESS_XZ.
862 mod_compress_cmd = true
863 ifdef CONFIG_MODULE_COMPRESS
864 ifdef CONFIG_MODULE_COMPRESS_GZIP
865 mod_compress_cmd = gzip -n
866 endif # CONFIG_MODULE_COMPRESS_GZIP
867 ifdef CONFIG_MODULE_COMPRESS_XZ
868 mod_compress_cmd = xz
869 endif # CONFIG_MODULE_COMPRESS_XZ
870 endif # CONFIG_MODULE_COMPRESS
871 export mod_compress_cmd
873 # Select initial ramdisk compression format, default is gzip(1).
874 # This shall be used by the dracut(8) tool while creating an initramfs image.
876 INITRD_COMPRESS-y := gzip
877 INITRD_COMPRESS-$(CONFIG_RD_BZIP2) := bzip2
878 INITRD_COMPRESS-$(CONFIG_RD_LZMA) := lzma
879 INITRD_COMPRESS-$(CONFIG_RD_XZ) := xz
880 INITRD_COMPRESS-$(CONFIG_RD_LZO) := lzo
881 INITRD_COMPRESS-$(CONFIG_RD_LZ4) := lz4
882 # do not export INITRD_COMPRESS, since we didn't actually
883 # choose a sane default compression above.
884 # export INITRD_COMPRESS := $(INITRD_COMPRESS-y)
886 ifdef CONFIG_MODULE_SIG_ALL
887 MODSECKEY = ./signing_key.priv
888 MODPUBKEY = ./signing_key.x509
890 mod_sign_cmd = perl $(srctree)/scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODSECKEY) $(MODPUBKEY)
897 ifeq ($(KBUILD_EXTMOD),)
898 core-y += kernel/ mm/ fs/ ipc/ security/ crypto/ block/
900 vmlinux-dirs := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
901 $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
902 $(net-y) $(net-m) $(libs-y) $(libs-m)))
904 vmlinux-alldirs := $(sort $(vmlinux-dirs) $(patsubst %/,%,$(filter %/, \
905 $(init-) $(core-) $(drivers-) $(net-) $(libs-))))
907 init-y := $(patsubst %/, %/built-in.o, $(init-y))
908 core-y := $(patsubst %/, %/built-in.o, $(core-y))
909 drivers-y := $(patsubst %/, %/built-in.o, $(drivers-y))
910 net-y := $(patsubst %/, %/built-in.o, $(net-y))
911 libs-y1 := $(patsubst %/, %/lib.a, $(libs-y))
912 libs-y2 := $(patsubst %/, %/built-in.o, $(libs-y))
913 libs-y := $(libs-y1) $(libs-y2)
915 # Externally visible symbols (used by link-vmlinux.sh)
916 export KBUILD_VMLINUX_INIT := $(head-y) $(init-y)
917 export KBUILD_VMLINUX_MAIN := $(core-y) $(libs-y) $(drivers-y) $(net-y)
918 export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
919 export LDFLAGS_vmlinux
920 # used by scripts/pacmage/Makefile
921 export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) arch Documentation include samples scripts tools virt)
923 vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_INIT) $(KBUILD_VMLINUX_MAIN)
925 # Final link of vmlinux
926 cmd_link-vmlinux = $(CONFIG_SHELL) $< $(LD) $(LDFLAGS) $(LDFLAGS_vmlinux)
927 quiet_cmd_link-vmlinux = LINK $@
929 # Include targets which we want to
930 # execute if the rest of the kernel build went well.
931 vmlinux: scripts/link-vmlinux.sh $(vmlinux-deps) FORCE
932 ifdef CONFIG_HEADERS_CHECK
933 $(Q)$(MAKE) -f $(srctree)/Makefile headers_check
936 $(Q)$(MAKE) $(build)=samples
938 ifdef CONFIG_BUILD_DOCSRC
939 $(Q)$(MAKE) $(build)=Documentation
941 +$(call if_changed,link-vmlinux)
943 # The actual objects are generated when descending,
944 # make sure no implicit rule kicks in
945 $(sort $(vmlinux-deps)): $(vmlinux-dirs) ;
947 # Handle descending into subdirectories listed in $(vmlinux-dirs)
948 # Preset locale variables to speed up the build process. Limit locale
949 # tweaks to this spot to avoid wrong language settings when running
950 # make menuconfig etc.
951 # Error messages still appears in the original language
953 PHONY += $(vmlinux-dirs)
954 $(vmlinux-dirs): prepare scripts
955 $(Q)$(MAKE) $(build)=$@
957 define filechk_kernel.release
958 echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
961 # Store (new) KERNELRELEASE string in include/config/kernel.release
962 include/config/kernel.release: include/config/auto.conf FORCE
963 $(call filechk,kernel.release)
966 # Things we need to do before we recursively start building the kernel
967 # or the modules are listed in "prepare".
968 # A multi level approach is used. prepareN is processed before prepareN-1.
969 # archprepare is used in arch Makefiles and when processed asm symlink,
970 # version.h and scripts_basic is processed / created.
972 # Listed in dependency order
973 PHONY += prepare archprepare prepare0 prepare1 prepare2 prepare3
975 # prepare3 is used to check if we are building in a separate output directory,
977 # 1) Check that make has not been executed in the kernel src $(srctree)
978 prepare3: include/config/kernel.release
979 ifneq ($(KBUILD_SRC),)
980 @$(kecho) ' Using $(srctree) as source for kernel'
981 $(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \
982 echo >&2 " $(srctree) is not clean, please run 'make mrproper'"; \
983 echo >&2 " in the '$(srctree)' directory.";\
988 # prepare2 creates a makefile if using a separate output directory
989 prepare2: prepare3 outputmakefile asm-generic
991 prepare1: prepare2 $(version_h) include/generated/utsrelease.h \
992 include/config/auto.conf
995 archprepare: archheaders archscripts prepare1 scripts_basic
997 prepare0: archprepare FORCE
998 $(Q)$(MAKE) $(build)=.
1000 # All the preparing..
1003 # Generate some files
1004 # ---------------------------------------------------------------------------
1006 # KERNELRELEASE can change from a few different places, meaning version.h
1007 # needs to be updated, so this check is forced on all builds
1010 define filechk_utsrelease.h
1011 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1012 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1015 (echo \#define UTS_RELEASE \"$(KERNELRELEASE)\";)
1018 define filechk_version.h
1019 (echo \#define LINUX_VERSION_CODE $(shell \
1020 expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1021 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))';)
1024 $(version_h): $(srctree)/Makefile FORCE
1025 $(call filechk,version.h)
1026 $(Q)rm -f $(old_version_h)
1028 include/generated/utsrelease.h: include/config/kernel.release FORCE
1029 $(call filechk,utsrelease.h)
1033 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1034 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1036 # ---------------------------------------------------------------------------
1040 @echo '*** Warning: make $@ is unnecessary now.'
1042 # ---------------------------------------------------------------------------
1044 INSTALL_FW_PATH=$(INSTALL_MOD_PATH)/lib/firmware
1045 export INSTALL_FW_PATH
1047 PHONY += firmware_install
1048 firmware_install: FORCE
1049 @mkdir -p $(objtree)/firmware
1050 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_install
1052 # ---------------------------------------------------------------------------
1055 #Default location for installed headers
1056 export INSTALL_HDR_PATH = $(objtree)/usr
1058 # If we do an all arch process set dst to asm-$(hdr-arch)
1059 hdr-dst = $(if $(KBUILD_HEADERS), dst=include/asm-$(hdr-arch), dst=include/asm)
1061 PHONY += archheaders
1064 PHONY += archscripts
1068 __headers: $(version_h) scripts_basic asm-generic archheaders archscripts FORCE
1069 $(Q)$(MAKE) $(build)=scripts build_unifdef
1071 PHONY += headers_install_all
1072 headers_install_all:
1073 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh install
1075 PHONY += headers_install
1076 headers_install: __headers
1077 $(if $(wildcard $(srctree)/arch/$(hdr-arch)/include/uapi/asm/Kbuild),, \
1078 $(error Headers not exportable for the $(SRCARCH) architecture))
1079 $(Q)$(MAKE) $(hdr-inst)=include/uapi
1080 $(Q)$(MAKE) $(hdr-inst)=arch/$(hdr-arch)/include/uapi/asm $(hdr-dst)
1082 PHONY += headers_check_all
1083 headers_check_all: headers_install_all
1084 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh check
1086 PHONY += headers_check
1087 headers_check: headers_install
1088 $(Q)$(MAKE) $(hdr-inst)=include/uapi HDRCHECK=1
1089 $(Q)$(MAKE) $(hdr-inst)=arch/$(hdr-arch)/include/uapi/asm $(hdr-dst) HDRCHECK=1
1091 # ---------------------------------------------------------------------------
1096 $(Q)$(MAKE) -C tools/testing/selftests run_tests
1098 # ---------------------------------------------------------------------------
1101 ifdef CONFIG_MODULES
1103 # By default, build modules as well
1109 # A module can be listed more than once in obj-m resulting in
1110 # duplicate lines in modules.order files. Those are removed
1111 # using awk while concatenating to the final file.
1114 modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux) modules.builtin
1115 $(Q)$(AWK) '!x[$$0]++' $(vmlinux-dirs:%=$(objtree)/%/modules.order) > $(objtree)/modules.order
1116 @$(kecho) ' Building modules, stage 2.';
1117 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1118 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_modbuild
1120 modules.builtin: $(vmlinux-dirs:%=%/modules.builtin)
1121 $(Q)$(AWK) '!x[$$0]++' $^ > $(objtree)/modules.builtin
1123 %/modules.builtin: include/config/auto.conf
1124 $(Q)$(MAKE) $(modbuiltin)=$*
1127 # Target to prepare building external modules
1128 PHONY += modules_prepare
1129 modules_prepare: prepare scripts
1131 # Target to install modules
1132 PHONY += modules_install
1133 modules_install: _modinst_ _modinst_post
1137 @rm -rf $(MODLIB)/kernel
1138 @rm -f $(MODLIB)/source
1139 @mkdir -p $(MODLIB)/kernel
1140 @ln -s `cd $(srctree) && /bin/pwd` $(MODLIB)/source
1141 @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
1142 rm -f $(MODLIB)/build ; \
1143 ln -s $(CURDIR) $(MODLIB)/build ; \
1145 @cp -f $(objtree)/modules.order $(MODLIB)/
1146 @cp -f $(objtree)/modules.builtin $(MODLIB)/
1147 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1149 # This depmod is only for convenience to give the initial
1150 # boot a modules.dep even before / is mounted read-write. However the
1151 # boot script depmod is the master version.
1152 PHONY += _modinst_post
1153 _modinst_post: _modinst_
1154 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_modinst
1157 ifeq ($(CONFIG_MODULE_SIG), y)
1158 PHONY += modules_sign
1160 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1163 else # CONFIG_MODULES
1165 # Modules not configured
1166 # ---------------------------------------------------------------------------
1168 modules modules_install: FORCE
1170 @echo >&2 "The present kernel configuration has modules disabled."
1171 @echo >&2 "Type 'make config' and enable loadable module support."
1172 @echo >&2 "Then build a kernel with module support enabled."
1176 endif # CONFIG_MODULES
1179 # Cleaning is done on three levels.
1180 # make clean Delete most generated files
1181 # Leave enough to build external modules
1182 # make mrproper Delete the current configuration, and all generated files
1183 # make distclean Remove editor backup files, patch leftover files and the like
1185 # Directories & files removed with 'make clean'
1186 CLEAN_DIRS += $(MODVERDIR)
1188 # Directories & files removed with 'make mrproper'
1189 MRPROPER_DIRS += include/config usr/include include/generated \
1190 arch/*/include/generated .tmp_objdiff
1191 MRPROPER_FILES += .config .config.old .version .old_version \
1192 Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS \
1193 signing_key.priv signing_key.x509 x509.genkey \
1194 extra_certificates signing_key.x509.keyid \
1195 signing_key.x509.signer
1197 # clean - Delete most, but leave enough to build external modules
1199 clean: rm-dirs := $(CLEAN_DIRS)
1200 clean: rm-files := $(CLEAN_FILES)
1201 clean-dirs := $(addprefix _clean_, . $(vmlinux-alldirs) Documentation samples)
1203 PHONY += $(clean-dirs) clean archclean vmlinuxclean
1205 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1208 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1210 clean: archclean vmlinuxclean
1212 # mrproper - Delete all generated files, including .config
1214 mrproper: rm-dirs := $(wildcard $(MRPROPER_DIRS))
1215 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1216 mrproper-dirs := $(addprefix _mrproper_,Documentation/DocBook scripts)
1218 PHONY += $(mrproper-dirs) mrproper archmrproper
1220 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1222 mrproper: clean archmrproper $(mrproper-dirs)
1231 @find $(srctree) $(RCS_FIND_IGNORE) \
1232 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1233 -o -name '*.bak' -o -name '#*#' -o -name '.*.orig' \
1234 -o -name '.*.rej' -o -name '*%' -o -name 'core' \) \
1235 -type f -print | xargs rm -f
1238 # Packaging of the kernel to various formats
1239 # ---------------------------------------------------------------------------
1240 # rpm target kept for backward compatibility
1241 package-dir := scripts/package
1244 $(Q)$(MAKE) $(build)=$(package-dir) $@
1245 %pkg: include/config/kernel.release FORCE
1246 $(Q)$(MAKE) $(build)=$(package-dir) $@
1247 rpm: include/config/kernel.release FORCE
1248 $(Q)$(MAKE) $(build)=$(package-dir) $@
1251 # Brief documentation of the typical targets used
1252 # ---------------------------------------------------------------------------
1254 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1255 boards := $(sort $(notdir $(boards)))
1256 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1257 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1260 @echo 'Cleaning targets:'
1261 @echo ' clean - Remove most generated files but keep the config and'
1262 @echo ' enough build support to build external modules'
1263 @echo ' mrproper - Remove all generated files + config + various backup files'
1264 @echo ' distclean - mrproper + remove editor backup and patch files'
1266 @echo 'Configuration targets:'
1267 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1269 @echo 'Other generic targets:'
1270 @echo ' all - Build all targets marked with [*]'
1271 @echo '* vmlinux - Build the bare kernel'
1272 @echo '* modules - Build all modules'
1273 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1274 @echo ' firmware_install- Install all firmware to INSTALL_FW_PATH'
1275 @echo ' (default: $$(INSTALL_MOD_PATH)/lib/firmware)'
1276 @echo ' dir/ - Build all files in dir and below'
1277 @echo ' dir/file.[oisS] - Build specified target only'
1278 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1279 @echo ' (requires a recent binutils and recent build (System.map))'
1280 @echo ' dir/file.ko - Build module including final link'
1281 @echo ' modules_prepare - Set up for building external modules'
1282 @echo ' tags/TAGS - Generate tags file for editors'
1283 @echo ' cscope - Generate cscope index'
1284 @echo ' gtags - Generate GNU GLOBAL index'
1285 @echo ' kernelrelease - Output the release version string (use with make -s)'
1286 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1287 @echo ' image_name - Output the image name (use with make -s)'
1288 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1289 echo ' (default: $(INSTALL_HDR_PATH))'; \
1291 @echo 'Static analysers'
1292 @echo ' checkstack - Generate a list of stack hogs'
1293 @echo ' namespacecheck - Name space analysis on compiled kernel'
1294 @echo ' versioncheck - Sanity check on version.h usage'
1295 @echo ' includecheck - Check for duplicate included header files'
1296 @echo ' export_report - List the usages of all exported symbols'
1297 @echo ' headers_check - Sanity check on exported headers'
1298 @echo ' headerdep - Detect inclusion cycles in headers'
1299 @$(MAKE) -f $(srctree)/scripts/Makefile.help checker-help
1301 @echo 'Kernel selftest'
1302 @echo ' kselftest - Build and run kernel selftest (run as root)'
1303 @echo ' Build, install, and boot kernel before'
1304 @echo ' running kselftest on it'
1306 @echo 'Kernel packaging:'
1307 @$(MAKE) $(build)=$(package-dir) help
1309 @echo 'Documentation targets:'
1310 @$(MAKE) -f $(srctree)/Documentation/DocBook/Makefile dochelp
1312 @echo 'Architecture specific targets ($(SRCARCH)):'
1313 @$(if $(archhelp),$(archhelp),\
1314 echo ' No architecture specific help defined for $(SRCARCH)')
1317 $(foreach b, $(boards), \
1318 printf " %-24s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1320 @$(if $(board-dirs), \
1321 $(foreach b, $(board-dirs), \
1322 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1323 printf " %-16s - Show all of the above\\n" help-boards; \
1326 @echo ' make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1327 @echo ' make V=2 [targets] 2 => give reason for rebuild of target'
1328 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1329 @echo ' make C=1 [targets] Check all c source with $$CHECK (sparse by default)'
1330 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1331 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1332 @echo ' make W=n [targets] Enable extra gcc checks, n=1,2,3 where'
1333 @echo ' 1: warnings which may be relevant and do not occur too often'
1334 @echo ' 2: warnings which occur quite often but may still be relevant'
1335 @echo ' 3: more obscure warnings, can most likely be ignored'
1336 @echo ' Multiple levels can be combined with W=12 or W=123'
1338 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1339 @echo 'For further info see the ./README file'
1342 help-board-dirs := $(addprefix help-,$(board-dirs))
1344 help-boards: $(help-board-dirs)
1346 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1348 $(help-board-dirs): help-%:
1349 @echo 'Architecture specific targets ($(SRCARCH) $*):'
1350 @$(if $(boards-per-dir), \
1351 $(foreach b, $(boards-per-dir), \
1352 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1356 # Documentation targets
1357 # ---------------------------------------------------------------------------
1358 %docs: scripts_basic FORCE
1359 $(Q)$(MAKE) $(build)=scripts build_docproc
1360 $(Q)$(MAKE) $(build)=Documentation/DocBook $@
1362 else # KBUILD_EXTMOD
1365 # External module support.
1366 # When building external modules the kernel used as basis is considered
1367 # read-only, and no consistency checks are made and the make
1368 # system is not used on the basis kernel. If updates are required
1369 # in the basis kernel ordinary make commands (without M=...) must
1372 # The following are the only valid targets when building external
1374 # make M=dir clean Delete all automatically generated files
1375 # make M=dir modules Make all modules in specified dir
1376 # make M=dir Same as 'make M=dir modules'
1377 # make M=dir modules_install
1378 # Install the modules built in the module directory
1379 # Assumes install directory is already created
1381 # We are always building modules
1383 PHONY += crmodverdir
1387 PHONY += $(objtree)/Module.symvers
1388 $(objtree)/Module.symvers:
1389 @test -e $(objtree)/Module.symvers || ( \
1391 echo " WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1392 echo " is missing; modules will have no dependencies and modversions."; \
1395 module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
1396 PHONY += $(module-dirs) modules
1397 $(module-dirs): crmodverdir $(objtree)/Module.symvers
1398 $(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@)
1400 modules: $(module-dirs)
1401 @$(kecho) ' Building modules, stage 2.';
1402 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1404 PHONY += modules_install
1405 modules_install: _emodinst_ _emodinst_post
1407 install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1410 $(Q)mkdir -p $(MODLIB)/$(install-dir)
1411 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1413 PHONY += _emodinst_post
1414 _emodinst_post: _emodinst_
1417 clean-dirs := $(addprefix _clean_,$(KBUILD_EXTMOD))
1419 PHONY += $(clean-dirs) clean
1421 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1423 clean: rm-dirs := $(MODVERDIR)
1424 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers
1427 @echo ' Building external modules.'
1428 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1430 @echo ' modules - default target, build the module(s)'
1431 @echo ' modules_install - install the module'
1432 @echo ' clean - remove generated files in module directory only'
1436 PHONY += prepare scripts
1439 endif # KBUILD_EXTMOD
1441 clean: $(clean-dirs)
1444 @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1445 \( -name '*.[oas]' -o -name '*.ko' -o -name '.*.cmd' \
1448 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1449 -o -name '*.symtypes' -o -name 'modules.order' \
1450 -o -name modules.builtin -o -name '.tmp_*.o.*' \
1451 -o -name '*.gcno' \) -type f -print | xargs rm -f
1453 # Generate tags for editors
1454 # ---------------------------------------------------------------------------
1455 quiet_cmd_tags = GEN $@
1456 cmd_tags = $(CONFIG_SHELL) $(srctree)/scripts/tags.sh $@
1458 tags TAGS cscope gtags: FORCE
1461 # Scripts to check various things for consistency
1462 # ---------------------------------------------------------------------------
1464 PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1467 find $(srctree)/* $(RCS_FIND_IGNORE) \
1468 -name '*.[hcS]' -type f -print | sort \
1469 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1472 find $(srctree)/* $(RCS_FIND_IGNORE) \
1473 -name '*.[hcS]' -type f -print | sort \
1474 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1477 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/$@
1480 $(PERL) $(srctree)/scripts/namespace.pl
1483 $(PERL) $(srctree)/scripts/export_report.pl
1485 endif #ifeq ($(config-targets),1)
1486 endif #ifeq ($(mixed-targets),1)
1488 PHONY += checkstack kernelrelease kernelversion image_name
1490 # UML needs a little special treatment here. It wants to use the host
1491 # toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
1492 # else wants $(ARCH), including people doing cross-builds, which means
1493 # that $(SUBARCH) doesn't work here.
1495 CHECKSTACK_ARCH := $(SUBARCH)
1497 CHECKSTACK_ARCH := $(ARCH)
1500 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1501 $(PERL) $(src)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1504 @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1507 @echo $(KERNELVERSION)
1510 @echo $(KBUILD_IMAGE)
1512 # Clear a bunch of variables before executing the submake
1514 $(Q)mkdir -p $(objtree)/tools
1515 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(filter --j% -j,$(MAKEFLAGS))" O=$(objtree) subdir=tools -C $(src)/tools/
1518 $(Q)mkdir -p $(objtree)/tools
1519 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(filter --j% -j,$(MAKEFLAGS))" O=$(objtree) subdir=tools -C $(src)/tools/ $*
1522 # ---------------------------------------------------------------------------
1523 # Single targets are compatible with:
1524 # - build with mixed source and output
1525 # - build with separate output dir 'make O=...'
1526 # - external modules
1528 # target-dir => where to store outputfile
1529 # build-dir => directory in kernel source tree to use
1531 ifeq ($(KBUILD_EXTMOD),)
1532 build-dir = $(patsubst %/,%,$(dir $@))
1533 target-dir = $(dir $@)
1535 zap-slash=$(filter-out .,$(patsubst %/,%,$(dir $@)))
1536 build-dir = $(KBUILD_EXTMOD)$(if $(zap-slash),/$(zap-slash))
1537 target-dir = $(if $(KBUILD_EXTMOD),$(dir $<),$(dir $@))
1540 %.s: %.c prepare scripts FORCE
1541 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1542 %.i: %.c prepare scripts FORCE
1543 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1544 %.o: %.c prepare scripts FORCE
1545 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1546 %.lst: %.c prepare scripts FORCE
1547 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1548 %.s: %.S prepare scripts FORCE
1549 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1550 %.o: %.S prepare scripts FORCE
1551 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1552 %.symtypes: %.c prepare scripts FORCE
1553 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1556 /: prepare scripts FORCE
1558 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1559 $(build)=$(build-dir)
1560 # Make sure the latest headers are built for Documentation
1561 Documentation/: headers_install
1562 %/: prepare scripts FORCE
1564 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1565 $(build)=$(build-dir)
1566 %.ko: prepare scripts FORCE
1568 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1569 $(build)=$(build-dir) $(@:.ko=.o)
1570 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1572 # FIXME Should go into a make.lib or something
1573 # ===========================================================================
1575 quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN $(wildcard $(rm-dirs)))
1576 cmd_rmdirs = rm -rf $(rm-dirs)
1578 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
1579 cmd_rmfiles = rm -f $(rm-files)
1581 # Run depmod only if we have System.map and depmod is executable
1582 quiet_cmd_depmod = DEPMOD $(KERNELRELEASE)
1583 cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1584 $(KERNELRELEASE) "$(patsubst y,_,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX))"
1586 # Create temporary dir for module support files
1587 # clean it up only when building all modules
1588 cmd_crmodverdir = $(Q)mkdir -p $(MODVERDIR) \
1589 $(if $(KBUILD_MODULES),; rm -f $(MODVERDIR)/*)
1591 # read all saved command lines
1593 targets := $(wildcard $(sort $(targets)))
1594 cmd_files := $(wildcard .*.cmd $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
1596 ifneq ($(cmd_files),)
1597 $(cmd_files): ; # Do not try to update included dependency files
1598 include $(cmd_files)
1601 endif # skip-makefile
1606 # Declare the contents of the .PHONY variable as phony. We keep that
1607 # information in a variable so we can use it in if_changed and friends.