5 NAME = Hurr durr I'ma sheep
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 $(CURDIR)/Makefile Makefile: ;
131 ifneq ($(KBUILD_OUTPUT),)
132 # Invoke a second make in the output directory, passing relevant variables
133 # check that the output directory actually exists
134 saved-output := $(KBUILD_OUTPUT)
135 KBUILD_OUTPUT := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) \
137 $(if $(KBUILD_OUTPUT),, \
138 $(error failed to create output directory "$(saved-output)"))
140 PHONY += $(MAKECMDGOALS) sub-make
142 $(filter-out _all sub-make $(CURDIR)/Makefile, $(MAKECMDGOALS)) _all: sub-make
146 $(Q)$(MAKE) -C $(KBUILD_OUTPUT) KBUILD_SRC=$(CURDIR) \
147 -f $(CURDIR)/Makefile $(filter-out _all sub-make,$(MAKECMDGOALS))
149 # Leave processing to above invocation of make
151 endif # ifneq ($(KBUILD_OUTPUT),)
152 endif # ifeq ($(KBUILD_SRC),)
154 # We process the rest of the Makefile if this is the final invocation of make
155 ifeq ($(skip-makefile),)
157 # Do not print "Entering directory ...",
158 # but we want to display it when entering to the output directory
159 # so that IDEs/editors are able to understand relative filenames.
160 MAKEFLAGS += --no-print-directory
162 # Call a source code checker (by default, "sparse") as part of the
165 # Use 'make C=1' to enable checking of only re-compiled files.
166 # Use 'make C=2' to enable checking of *all* source files, regardless
167 # of whether they are re-compiled or not.
169 # See the file "Documentation/sparse.txt" for more details, including
170 # where to get the "sparse" utility.
172 ifeq ("$(origin C)", "command line")
173 KBUILD_CHECKSRC = $(C)
175 ifndef KBUILD_CHECKSRC
179 # Use make M=dir to specify directory of external module to build
180 # Old syntax make ... SUBDIRS=$PWD is still supported
181 # Setting the environment variable KBUILD_EXTMOD take precedence
183 KBUILD_EXTMOD ?= $(SUBDIRS)
186 ifeq ("$(origin M)", "command line")
187 KBUILD_EXTMOD := $(M)
190 # If building an external module we do not care about the all: rule
191 # but instead _all depend on modules
193 ifeq ($(KBUILD_EXTMOD),)
199 ifeq ($(KBUILD_SRC),)
200 # building in the source tree
203 ifeq ($(KBUILD_SRC)/,$(dir $(CURDIR)))
204 # building in a subdirectory of the source tree
207 srctree := $(KBUILD_SRC)
214 VPATH := $(srctree)$(if $(KBUILD_EXTMOD),:$(KBUILD_EXTMOD))
216 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
338 # We need some generic definitions (do not try to remake the file).
339 scripts/Kbuild.include: ;
340 include scripts/Kbuild.include
342 # Make variables (CC, etc...)
343 AS = $(CROSS_COMPILE)as
344 LD = $(CROSS_COMPILE)ld
345 CC = $(CROSS_COMPILE)gcc
347 AR = $(CROSS_COMPILE)ar
348 NM = $(CROSS_COMPILE)nm
349 STRIP = $(CROSS_COMPILE)strip
350 OBJCOPY = $(CROSS_COMPILE)objcopy
351 OBJDUMP = $(CROSS_COMPILE)objdump
353 GENKSYMS = scripts/genksyms/genksyms
354 INSTALLKERNEL := installkernel
355 DEPMOD = /sbin/depmod
360 CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
361 -Wbitwise -Wno-return-void $(CF)
367 CFLAGS_GCOV = -fprofile-arcs -ftest-coverage
370 # Use USERINCLUDE when you must reference the UAPI directories only.
372 -I$(srctree)/arch/$(hdr-arch)/include/uapi \
373 -Iarch/$(hdr-arch)/include/generated/uapi \
374 -I$(srctree)/include/uapi \
375 -Iinclude/generated/uapi \
376 -include $(srctree)/include/linux/kconfig.h
378 # Use LINUXINCLUDE when you must reference the include/ directory.
379 # Needed to be compatible with the O= option
381 -I$(srctree)/arch/$(hdr-arch)/include \
382 -Iarch/$(hdr-arch)/include/generated/uapi \
383 -Iarch/$(hdr-arch)/include/generated \
384 $(if $(KBUILD_SRC), -I$(srctree)/include) \
388 KBUILD_CPPFLAGS := -D__KERNEL__
390 KBUILD_CFLAGS := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
391 -fno-strict-aliasing -fno-common \
392 -Werror-implicit-function-declaration \
393 -Wno-format-security \
396 KBUILD_AFLAGS_KERNEL :=
397 KBUILD_CFLAGS_KERNEL :=
398 KBUILD_AFLAGS := -D__ASSEMBLY__
399 KBUILD_AFLAGS_MODULE := -DMODULE
400 KBUILD_CFLAGS_MODULE := -DMODULE
401 KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
403 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
404 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
405 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
407 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
408 export ARCH SRCARCH CONFIG_SHELL HOSTCC HOSTCFLAGS CROSS_COMPILE AS LD CC
409 export CPP AR NM STRIP OBJCOPY OBJDUMP
410 export MAKE AWK GENKSYMS INSTALLKERNEL PERL PYTHON UTS_MACHINE
411 export HOSTCXX HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
413 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS LDFLAGS
414 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE CFLAGS_GCOV CFLAGS_KASAN
415 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
416 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
417 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
418 export KBUILD_ARFLAGS
420 # When compiling out-of-tree modules, put MODVERDIR in the module
421 # tree rather than in the kernel tree. The kernel tree might
423 export MODVERDIR := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_versions
425 # Files to ignore in find ... statements
427 export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o \
428 -name CVS -o -name .pc -o -name .hg -o -name .git \) \
430 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
431 --exclude CVS --exclude .pc --exclude .hg --exclude .git
433 # ===========================================================================
434 # Rules shared between *config targets and build targets
436 # Basic helpers built in scripts/
437 PHONY += scripts_basic
439 $(Q)$(MAKE) $(build)=scripts/basic
440 $(Q)rm -f .tmp_quiet_recordmcount
442 # To avoid any implicit rule to kick in, define an empty command.
443 scripts/basic/%: scripts_basic ;
445 PHONY += outputmakefile
446 # outputmakefile generates a Makefile in the output directory, if using a
447 # separate output directory. This allows convenient use of make in the
450 ifneq ($(KBUILD_SRC),)
451 $(Q)ln -fsn $(srctree) source
452 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile \
453 $(srctree) $(objtree) $(VERSION) $(PATCHLEVEL)
456 # Support for using generic headers in asm-generic
459 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
460 src=asm obj=arch/$(SRCARCH)/include/generated/asm
461 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
462 src=uapi/asm obj=arch/$(SRCARCH)/include/generated/uapi/asm
464 # To make sure we do not include .config for any of the *config targets
465 # catch them early, and hand them over to scripts/kconfig/Makefile
466 # It is allowed to specify more targets when calling make, including
467 # mixing *config targets and build targets.
468 # For example 'make oldconfig all'.
469 # Detect when mixed targets is specified, and make a second invocation
470 # of make so .config is not included in this case either (for *config).
472 version_h := include/generated/uapi/linux/version.h
473 old_version_h := include/linux/version.h
475 no-dot-config-targets := clean mrproper distclean \
476 cscope gtags TAGS tags help% %docs check% coccicheck \
477 $(version_h) headers_% archheaders archscripts \
478 kernelversion %src-pkg
484 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
485 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
490 ifeq ($(KBUILD_EXTMOD),)
491 ifneq ($(filter config %config,$(MAKECMDGOALS)),)
493 ifneq ($(words $(MAKECMDGOALS)),1)
499 ifeq ($(mixed-targets),1)
500 # ===========================================================================
501 # We're called with mixed targets (*config and build targets).
502 # Handle them one by one.
504 PHONY += $(MAKECMDGOALS) __build_one_by_one
506 $(filter-out __build_one_by_one, $(MAKECMDGOALS)): __build_one_by_one
511 for i in $(MAKECMDGOALS); do \
512 $(MAKE) -f $(srctree)/Makefile $$i; \
516 ifeq ($(config-targets),1)
517 # ===========================================================================
518 # *config targets only - make sure prerequisites are updated, and descend
519 # in scripts/kconfig to make the *config target
521 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
522 # KBUILD_DEFCONFIG may point out an alternative default configuration
523 # used for 'make defconfig'
524 include arch/$(SRCARCH)/Makefile
525 export KBUILD_DEFCONFIG KBUILD_KCONFIG
527 config: scripts_basic outputmakefile FORCE
528 $(Q)$(MAKE) $(build)=scripts/kconfig $@
530 %config: scripts_basic outputmakefile FORCE
531 $(Q)$(MAKE) $(build)=scripts/kconfig $@
534 # ===========================================================================
535 # Build targets only - this includes vmlinux, arch specific targets, clean
536 # targets and others. In general all targets except *config targets.
538 ifeq ($(KBUILD_EXTMOD),)
539 # Additional helpers built in scripts/
540 # Carefully list dependencies so we do not try to build scripts twice
543 scripts: scripts_basic include/config/auto.conf include/config/tristate.conf \
545 $(Q)$(MAKE) $(build)=$(@)
547 # Objects we will link into vmlinux / subdirs we need to visit
549 drivers-y := drivers/ sound/ firmware/
553 endif # KBUILD_EXTMOD
555 ifeq ($(dot-config),1)
557 -include include/config/auto.conf
559 ifeq ($(KBUILD_EXTMOD),)
560 # Read in dependencies to all Kconfig* files, make sure to run
561 # oldconfig if changes are detected.
562 -include include/config/auto.conf.cmd
564 # To avoid any implicit rule to kick in, define an empty command
565 $(KCONFIG_CONFIG) include/config/auto.conf.cmd: ;
567 # If .config is newer than include/config/auto.conf, someone tinkered
568 # with it and forgot to run make oldconfig.
569 # if auto.conf.cmd is missing then we are probably in a cleaned tree so
570 # we execute the config step to be sure to catch updated Kconfig files
571 include/config/%.conf: $(KCONFIG_CONFIG) include/config/auto.conf.cmd
572 $(Q)$(MAKE) -f $(srctree)/Makefile silentoldconfig
574 # external modules needs include/generated/autoconf.h and include/config/auto.conf
575 # but do not care if they are up-to-date. Use auto.conf to trigger the test
576 PHONY += include/config/auto.conf
578 include/config/auto.conf:
579 $(Q)test -e include/generated/autoconf.h -a -e $@ || ( \
581 echo >&2 " ERROR: Kernel configuration is invalid."; \
582 echo >&2 " include/generated/autoconf.h or $@ are missing.";\
583 echo >&2 " Run 'make oldconfig && make prepare' on kernel src to fix it."; \
587 endif # KBUILD_EXTMOD
590 # Dummy target needed, because used as prerequisite
591 include/config/auto.conf: ;
592 endif # $(dot-config)
594 # The all: target is the default when no target is given on the
596 # This allow a user to issue only 'make' to build a kernel including modules
597 # Defaults to vmlinux, but the arch makefile usually adds further targets
600 include arch/$(SRCARCH)/Makefile
602 KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,)
604 ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
605 KBUILD_CFLAGS += -Os $(call cc-disable-warning,maybe-uninitialized,)
610 # Tell gcc to never replace conditional load with a non-conditional one
611 KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
613 ifdef CONFIG_READABLE_ASM
614 # Disable optimizations that make assembler listings hard to read.
615 # reorder blocks reorders the control in the function
616 # ipa clone creates specialized cloned functions
617 # partial inlining inlines only parts of functions
618 KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
619 $(call cc-option,-fno-ipa-cp-clone,) \
620 $(call cc-option,-fno-partial-inlining)
623 ifneq ($(CONFIG_FRAME_WARN),0)
624 KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
627 # Handle stack protector mode.
629 # Since kbuild can potentially perform two passes (first with the old
630 # .config values and then with updated .config values), we cannot error out
631 # if a desired compiler option is unsupported. If we were to error, kbuild
632 # could never get to the second pass and actually notice that we changed
633 # the option to something that was supported.
635 # Additionally, we don't want to fallback and/or silently change which compiler
636 # flags will be used, since that leads to producing kernels with different
637 # security feature characteristics depending on the compiler used. ("But I
638 # selected CC_STACKPROTECTOR_STRONG! Why did it build with _REGULAR?!")
640 # The middle ground is to warn here so that the failed option is obvious, but
641 # to let the build fail with bad compiler flags so that we can't produce a
642 # kernel when there is a CONFIG and compiler mismatch.
644 ifdef CONFIG_CC_STACKPROTECTOR_REGULAR
645 stackp-flag := -fstack-protector
646 ifeq ($(call cc-option, $(stackp-flag)),)
647 $(warning Cannot use CONFIG_CC_STACKPROTECTOR_REGULAR: \
648 -fstack-protector not supported by compiler)
651 ifdef CONFIG_CC_STACKPROTECTOR_STRONG
652 stackp-flag := -fstack-protector-strong
653 ifeq ($(call cc-option, $(stackp-flag)),)
654 $(warning Cannot use CONFIG_CC_STACKPROTECTOR_STRONG: \
655 -fstack-protector-strong not supported by compiler)
658 # Force off for distro compilers that enable stack protector by default.
659 stackp-flag := $(call cc-option, -fno-stack-protector)
662 KBUILD_CFLAGS += $(stackp-flag)
664 ifeq ($(shell $(CC) -v 2>&1 | grep -c "clang version"), 1)
671 ifeq ($(COMPILER),clang)
672 KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
673 KBUILD_CPPFLAGS += $(call cc-option,-Wno-unknown-warning-option,)
674 KBUILD_CFLAGS += $(call cc-disable-warning, unused-variable)
675 KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier)
676 KBUILD_CFLAGS += $(call cc-disable-warning, gnu)
677 # Quiet clang warning: comparison of unsigned expression < 0 is always false
678 KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare)
679 # CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
680 # source of a reference will be _MergedGlobals and not on of the whitelisted names.
681 # See modpost pattern 2
682 KBUILD_CFLAGS += $(call cc-option, -mno-global-merge,)
683 KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior)
686 # This warning generated too much noise in a regular build.
687 # Use make W=1 to enable this warning (see scripts/Makefile.build)
688 KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
691 ifdef CONFIG_FRAME_POINTER
692 KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
694 # Some targets (ARM with Thumb2, for example), can't be built with frame
695 # pointers. For those, we don't have FUNCTION_TRACER automatically
696 # select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
697 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
698 # -fomit-frame-pointer with FUNCTION_TRACER.
699 ifndef CONFIG_FUNCTION_TRACER
700 KBUILD_CFLAGS += -fomit-frame-pointer
704 KBUILD_CFLAGS += $(call cc-option, -fno-var-tracking-assignments)
706 ifdef CONFIG_DEBUG_INFO
707 ifdef CONFIG_DEBUG_INFO_SPLIT
708 KBUILD_CFLAGS += $(call cc-option, -gsplit-dwarf, -g)
712 KBUILD_AFLAGS += -Wa,-gdwarf-2
714 ifdef CONFIG_DEBUG_INFO_DWARF4
715 KBUILD_CFLAGS += $(call cc-option, -gdwarf-4,)
718 ifdef CONFIG_DEBUG_INFO_REDUCED
719 KBUILD_CFLAGS += $(call cc-option, -femit-struct-debug-baseonly) \
720 $(call cc-option,-fno-var-tracking)
723 ifdef CONFIG_FUNCTION_TRACER
724 ifndef CC_FLAGS_FTRACE
725 CC_FLAGS_FTRACE := -pg
727 export CC_FLAGS_FTRACE
728 ifdef CONFIG_HAVE_FENTRY
729 CC_USING_FENTRY := $(call cc-option, -mfentry -DCC_USING_FENTRY)
731 KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_USING_FENTRY)
732 KBUILD_AFLAGS += $(CC_USING_FENTRY)
733 ifdef CONFIG_DYNAMIC_FTRACE
734 ifdef CONFIG_HAVE_C_RECORDMCOUNT
735 BUILD_C_RECORDMCOUNT := y
736 export BUILD_C_RECORDMCOUNT
741 # We trigger additional mismatches with less inlining
742 ifdef CONFIG_DEBUG_SECTION_MISMATCH
743 KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
746 # arch Makefile may override CC so keep this after arch Makefile is included
747 NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
748 CHECKFLAGS += $(NOSTDINC_FLAGS)
750 # warn about C99 declaration after statement
751 KBUILD_CFLAGS += $(call cc-option,-Wdeclaration-after-statement,)
753 # disable pointer signed / unsigned warnings in gcc 4.0
754 KBUILD_CFLAGS += $(call cc-disable-warning, pointer-sign)
756 # disable invalid "can't wrap" optimizations for signed / pointers
757 KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow)
759 # conserve stack if available
760 KBUILD_CFLAGS += $(call cc-option,-fconserve-stack)
762 # disallow errors like 'EXPORT_GPL(foo);' with missing header
763 KBUILD_CFLAGS += $(call cc-option,-Werror=implicit-int)
765 # require functions to have arguments in prototypes, not empty 'int foo()'
766 KBUILD_CFLAGS += $(call cc-option,-Werror=strict-prototypes)
768 # Prohibit date/time macros, which would make the build non-deterministic
769 KBUILD_CFLAGS += $(call cc-option,-Werror=date-time)
771 # use the deterministic mode of AR if available
772 KBUILD_ARFLAGS := $(call ar-option,D)
774 # check for 'asm goto'
775 ifeq ($(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC)), y)
776 KBUILD_CFLAGS += -DCC_HAVE_ASM_GOTO
777 KBUILD_AFLAGS += -DCC_HAVE_ASM_GOTO
780 include scripts/Makefile.kasan
781 include scripts/Makefile.extrawarn
783 # Add any arch overrides and user supplied CPPFLAGS, AFLAGS and CFLAGS as the
785 KBUILD_CPPFLAGS += $(ARCH_CPPFLAGS) $(KCPPFLAGS)
786 KBUILD_AFLAGS += $(ARCH_AFLAGS) $(KAFLAGS)
787 KBUILD_CFLAGS += $(ARCH_CFLAGS) $(KCFLAGS)
789 # Use --build-id when available.
790 LDFLAGS_BUILD_ID = $(patsubst -Wl$(comma)%,%,\
791 $(call cc-ldoption, -Wl$(comma)--build-id,))
792 KBUILD_LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID)
793 LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)
795 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
796 LDFLAGS_vmlinux += $(call ld-option, -X,)
799 # Default kernel image to build when no specific target is given.
800 # KBUILD_IMAGE may be overruled on the command line or
801 # set in the environment
802 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
804 export KBUILD_IMAGE ?= vmlinux
807 # INSTALL_PATH specifies where to place the updated kernel and system map
808 # images. Default is /boot, but you can set it to other values
809 export INSTALL_PATH ?= /boot
812 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
813 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
814 # an argument if needed. Otherwise it defaults to the kernel install path
816 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
819 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
820 # relocations required by build roots. This is not defined in the
821 # makefile but the argument can be passed to make if needed.
824 MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
828 # INSTALL_MOD_STRIP, if defined, will cause modules to be
829 # stripped after they are installed. If INSTALL_MOD_STRIP is '1', then
830 # the default option --strip-debug will be used. Otherwise,
831 # INSTALL_MOD_STRIP value will be used as the options to the strip command.
833 ifdef INSTALL_MOD_STRIP
834 ifeq ($(INSTALL_MOD_STRIP),1)
835 mod_strip_cmd = $(STRIP) --strip-debug
837 mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
838 endif # INSTALL_MOD_STRIP=1
841 endif # INSTALL_MOD_STRIP
844 # CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
845 # after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
846 # or CONFIG_MODULE_COMPRESS_XZ.
848 mod_compress_cmd = true
849 ifdef CONFIG_MODULE_COMPRESS
850 ifdef CONFIG_MODULE_COMPRESS_GZIP
851 mod_compress_cmd = gzip -n
852 endif # CONFIG_MODULE_COMPRESS_GZIP
853 ifdef CONFIG_MODULE_COMPRESS_XZ
854 mod_compress_cmd = xz
855 endif # CONFIG_MODULE_COMPRESS_XZ
856 endif # CONFIG_MODULE_COMPRESS
857 export mod_compress_cmd
859 # Select initial ramdisk compression format, default is gzip(1).
860 # This shall be used by the dracut(8) tool while creating an initramfs image.
862 INITRD_COMPRESS-y := gzip
863 INITRD_COMPRESS-$(CONFIG_RD_BZIP2) := bzip2
864 INITRD_COMPRESS-$(CONFIG_RD_LZMA) := lzma
865 INITRD_COMPRESS-$(CONFIG_RD_XZ) := xz
866 INITRD_COMPRESS-$(CONFIG_RD_LZO) := lzo
867 INITRD_COMPRESS-$(CONFIG_RD_LZ4) := lz4
868 # do not export INITRD_COMPRESS, since we didn't actually
869 # choose a sane default compression above.
870 # export INITRD_COMPRESS := $(INITRD_COMPRESS-y)
872 ifdef CONFIG_MODULE_SIG_ALL
873 MODSECKEY = ./signing_key.priv
874 MODPUBKEY = ./signing_key.x509
876 mod_sign_cmd = perl $(srctree)/scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODSECKEY) $(MODPUBKEY)
883 ifeq ($(KBUILD_EXTMOD),)
884 core-y += kernel/ mm/ fs/ ipc/ security/ crypto/ block/
886 vmlinux-dirs := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
887 $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
888 $(net-y) $(net-m) $(libs-y) $(libs-m)))
890 vmlinux-alldirs := $(sort $(vmlinux-dirs) $(patsubst %/,%,$(filter %/, \
891 $(init-) $(core-) $(drivers-) $(net-) $(libs-))))
893 init-y := $(patsubst %/, %/built-in.o, $(init-y))
894 core-y := $(patsubst %/, %/built-in.o, $(core-y))
895 drivers-y := $(patsubst %/, %/built-in.o, $(drivers-y))
896 net-y := $(patsubst %/, %/built-in.o, $(net-y))
897 libs-y1 := $(patsubst %/, %/lib.a, $(libs-y))
898 libs-y2 := $(patsubst %/, %/built-in.o, $(libs-y))
899 libs-y := $(libs-y1) $(libs-y2)
901 # Externally visible symbols (used by link-vmlinux.sh)
902 export KBUILD_VMLINUX_INIT := $(head-y) $(init-y)
903 export KBUILD_VMLINUX_MAIN := $(core-y) $(libs-y) $(drivers-y) $(net-y)
904 export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
905 export LDFLAGS_vmlinux
906 # used by scripts/pacmage/Makefile
907 export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) arch Documentation include samples scripts tools virt)
909 vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_INIT) $(KBUILD_VMLINUX_MAIN)
911 # Final link of vmlinux
912 cmd_link-vmlinux = $(CONFIG_SHELL) $< $(LD) $(LDFLAGS) $(LDFLAGS_vmlinux)
913 quiet_cmd_link-vmlinux = LINK $@
915 # Include targets which we want to
916 # execute if the rest of the kernel build went well.
917 vmlinux: scripts/link-vmlinux.sh $(vmlinux-deps) FORCE
918 ifdef CONFIG_HEADERS_CHECK
919 $(Q)$(MAKE) -f $(srctree)/Makefile headers_check
922 $(Q)$(MAKE) $(build)=samples
924 ifdef CONFIG_BUILD_DOCSRC
925 $(Q)$(MAKE) $(build)=Documentation
927 ifdef CONFIG_GDB_SCRIPTS
928 $(Q)ln -fsn `cd $(srctree) && /bin/pwd`/scripts/gdb/vmlinux-gdb.py
930 +$(call if_changed,link-vmlinux)
932 # The actual objects are generated when descending,
933 # make sure no implicit rule kicks in
934 $(sort $(vmlinux-deps)): $(vmlinux-dirs) ;
936 # Handle descending into subdirectories listed in $(vmlinux-dirs)
937 # Preset locale variables to speed up the build process. Limit locale
938 # tweaks to this spot to avoid wrong language settings when running
939 # make menuconfig etc.
940 # Error messages still appears in the original language
942 PHONY += $(vmlinux-dirs)
943 $(vmlinux-dirs): prepare scripts
944 $(Q)$(MAKE) $(build)=$@
946 define filechk_kernel.release
947 echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
950 # Store (new) KERNELRELEASE string in include/config/kernel.release
951 include/config/kernel.release: include/config/auto.conf FORCE
952 $(call filechk,kernel.release)
955 # Things we need to do before we recursively start building the kernel
956 # or the modules are listed in "prepare".
957 # A multi level approach is used. prepareN is processed before prepareN-1.
958 # archprepare is used in arch Makefiles and when processed asm symlink,
959 # version.h and scripts_basic is processed / created.
961 # Listed in dependency order
962 PHONY += prepare archprepare prepare0 prepare1 prepare2 prepare3
964 # prepare3 is used to check if we are building in a separate output directory,
966 # 1) Check that make has not been executed in the kernel src $(srctree)
967 prepare3: include/config/kernel.release
968 ifneq ($(KBUILD_SRC),)
969 @$(kecho) ' Using $(srctree) as source for kernel'
970 $(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \
971 echo >&2 " $(srctree) is not clean, please run 'make mrproper'"; \
972 echo >&2 " in the '$(srctree)' directory.";\
977 # prepare2 creates a makefile if using a separate output directory
978 prepare2: prepare3 outputmakefile asm-generic
980 prepare1: prepare2 $(version_h) include/generated/utsrelease.h \
981 include/config/auto.conf
984 archprepare: archheaders archscripts prepare1 scripts_basic
986 prepare0: archprepare FORCE
987 $(Q)$(MAKE) $(build)=.
989 # All the preparing..
992 # Generate some files
993 # ---------------------------------------------------------------------------
995 # KERNELRELEASE can change from a few different places, meaning version.h
996 # needs to be updated, so this check is forced on all builds
999 define filechk_utsrelease.h
1000 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1001 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1004 (echo \#define UTS_RELEASE \"$(KERNELRELEASE)\";)
1007 define filechk_version.h
1008 (echo \#define LINUX_VERSION_CODE $(shell \
1009 expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1010 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))';)
1013 $(version_h): $(srctree)/Makefile FORCE
1014 $(call filechk,version.h)
1015 $(Q)rm -f $(old_version_h)
1017 include/generated/utsrelease.h: include/config/kernel.release FORCE
1018 $(call filechk,utsrelease.h)
1022 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1023 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1025 # ---------------------------------------------------------------------------
1027 INSTALL_FW_PATH=$(INSTALL_MOD_PATH)/lib/firmware
1028 export INSTALL_FW_PATH
1030 PHONY += firmware_install
1031 firmware_install: FORCE
1032 @mkdir -p $(objtree)/firmware
1033 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_install
1035 # ---------------------------------------------------------------------------
1038 #Default location for installed headers
1039 export INSTALL_HDR_PATH = $(objtree)/usr
1041 # If we do an all arch process set dst to asm-$(hdr-arch)
1042 hdr-dst = $(if $(KBUILD_HEADERS), dst=include/asm-$(hdr-arch), dst=include/asm)
1044 PHONY += archheaders
1047 PHONY += archscripts
1051 __headers: $(version_h) scripts_basic asm-generic archheaders archscripts FORCE
1052 $(Q)$(MAKE) $(build)=scripts build_unifdef
1054 PHONY += headers_install_all
1055 headers_install_all:
1056 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh install
1058 PHONY += headers_install
1059 headers_install: __headers
1060 $(if $(wildcard $(srctree)/arch/$(hdr-arch)/include/uapi/asm/Kbuild),, \
1061 $(error Headers not exportable for the $(SRCARCH) architecture))
1062 $(Q)$(MAKE) $(hdr-inst)=include/uapi
1063 $(Q)$(MAKE) $(hdr-inst)=arch/$(hdr-arch)/include/uapi/asm $(hdr-dst)
1065 PHONY += headers_check_all
1066 headers_check_all: headers_install_all
1067 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh check
1069 PHONY += headers_check
1070 headers_check: headers_install
1071 $(Q)$(MAKE) $(hdr-inst)=include/uapi HDRCHECK=1
1072 $(Q)$(MAKE) $(hdr-inst)=arch/$(hdr-arch)/include/uapi/asm $(hdr-dst) HDRCHECK=1
1074 # ---------------------------------------------------------------------------
1079 $(Q)$(MAKE) -C tools/testing/selftests run_tests
1081 # ---------------------------------------------------------------------------
1084 ifdef CONFIG_MODULES
1086 # By default, build modules as well
1092 # A module can be listed more than once in obj-m resulting in
1093 # duplicate lines in modules.order files. Those are removed
1094 # using awk while concatenating to the final file.
1097 modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux) modules.builtin
1098 $(Q)$(AWK) '!x[$$0]++' $(vmlinux-dirs:%=$(objtree)/%/modules.order) > $(objtree)/modules.order
1099 @$(kecho) ' Building modules, stage 2.';
1100 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1101 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_modbuild
1103 modules.builtin: $(vmlinux-dirs:%=%/modules.builtin)
1104 $(Q)$(AWK) '!x[$$0]++' $^ > $(objtree)/modules.builtin
1106 %/modules.builtin: include/config/auto.conf
1107 $(Q)$(MAKE) $(modbuiltin)=$*
1110 # Target to prepare building external modules
1111 PHONY += modules_prepare
1112 modules_prepare: prepare scripts
1114 # Target to install modules
1115 PHONY += modules_install
1116 modules_install: _modinst_ _modinst_post
1120 @rm -rf $(MODLIB)/kernel
1121 @rm -f $(MODLIB)/source
1122 @mkdir -p $(MODLIB)/kernel
1123 @ln -s `cd $(srctree) && /bin/pwd` $(MODLIB)/source
1124 @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
1125 rm -f $(MODLIB)/build ; \
1126 ln -s $(CURDIR) $(MODLIB)/build ; \
1128 @cp -f $(objtree)/modules.order $(MODLIB)/
1129 @cp -f $(objtree)/modules.builtin $(MODLIB)/
1130 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1132 # This depmod is only for convenience to give the initial
1133 # boot a modules.dep even before / is mounted read-write. However the
1134 # boot script depmod is the master version.
1135 PHONY += _modinst_post
1136 _modinst_post: _modinst_
1137 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_modinst
1140 ifeq ($(CONFIG_MODULE_SIG), y)
1141 PHONY += modules_sign
1143 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1146 else # CONFIG_MODULES
1148 # Modules not configured
1149 # ---------------------------------------------------------------------------
1151 modules modules_install: FORCE
1153 @echo >&2 "The present kernel configuration has modules disabled."
1154 @echo >&2 "Type 'make config' and enable loadable module support."
1155 @echo >&2 "Then build a kernel with module support enabled."
1159 endif # CONFIG_MODULES
1162 # Cleaning is done on three levels.
1163 # make clean Delete most generated files
1164 # Leave enough to build external modules
1165 # make mrproper Delete the current configuration, and all generated files
1166 # make distclean Remove editor backup files, patch leftover files and the like
1168 # Directories & files removed with 'make clean'
1169 CLEAN_DIRS += $(MODVERDIR)
1171 # Directories & files removed with 'make mrproper'
1172 MRPROPER_DIRS += include/config usr/include include/generated \
1173 arch/*/include/generated .tmp_objdiff
1174 MRPROPER_FILES += .config .config.old .version .old_version \
1175 Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS \
1176 signing_key.priv signing_key.x509 x509.genkey \
1177 extra_certificates signing_key.x509.keyid \
1178 signing_key.x509.signer vmlinux-gdb.py
1180 # clean - Delete most, but leave enough to build external modules
1182 clean: rm-dirs := $(CLEAN_DIRS)
1183 clean: rm-files := $(CLEAN_FILES)
1184 clean-dirs := $(addprefix _clean_, . $(vmlinux-alldirs) Documentation samples)
1186 PHONY += $(clean-dirs) clean archclean vmlinuxclean
1188 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1191 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1193 clean: archclean vmlinuxclean
1195 # mrproper - Delete all generated files, including .config
1197 mrproper: rm-dirs := $(wildcard $(MRPROPER_DIRS))
1198 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1199 mrproper-dirs := $(addprefix _mrproper_,Documentation/DocBook scripts)
1201 PHONY += $(mrproper-dirs) mrproper archmrproper
1203 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1205 mrproper: clean archmrproper $(mrproper-dirs)
1214 @find $(srctree) $(RCS_FIND_IGNORE) \
1215 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1216 -o -name '*.bak' -o -name '#*#' -o -name '.*.orig' \
1217 -o -name '.*.rej' -o -name '*%' -o -name 'core' \) \
1218 -type f -print | xargs rm -f
1221 # Packaging of the kernel to various formats
1222 # ---------------------------------------------------------------------------
1223 # rpm target kept for backward compatibility
1224 package-dir := scripts/package
1227 $(Q)$(MAKE) $(build)=$(package-dir) $@
1228 %pkg: include/config/kernel.release FORCE
1229 $(Q)$(MAKE) $(build)=$(package-dir) $@
1230 rpm: include/config/kernel.release FORCE
1231 $(Q)$(MAKE) $(build)=$(package-dir) $@
1234 # Brief documentation of the typical targets used
1235 # ---------------------------------------------------------------------------
1237 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1238 boards := $(sort $(notdir $(boards)))
1239 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1240 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1243 @echo 'Cleaning targets:'
1244 @echo ' clean - Remove most generated files but keep the config and'
1245 @echo ' enough build support to build external modules'
1246 @echo ' mrproper - Remove all generated files + config + various backup files'
1247 @echo ' distclean - mrproper + remove editor backup and patch files'
1249 @echo 'Configuration targets:'
1250 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1252 @echo 'Other generic targets:'
1253 @echo ' all - Build all targets marked with [*]'
1254 @echo '* vmlinux - Build the bare kernel'
1255 @echo '* modules - Build all modules'
1256 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1257 @echo ' firmware_install- Install all firmware to INSTALL_FW_PATH'
1258 @echo ' (default: $$(INSTALL_MOD_PATH)/lib/firmware)'
1259 @echo ' dir/ - Build all files in dir and below'
1260 @echo ' dir/file.[oisS] - Build specified target only'
1261 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1262 @echo ' (requires a recent binutils and recent build (System.map))'
1263 @echo ' dir/file.ko - Build module including final link'
1264 @echo ' modules_prepare - Set up for building external modules'
1265 @echo ' tags/TAGS - Generate tags file for editors'
1266 @echo ' cscope - Generate cscope index'
1267 @echo ' gtags - Generate GNU GLOBAL index'
1268 @echo ' kernelrelease - Output the release version string (use with make -s)'
1269 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1270 @echo ' image_name - Output the image name (use with make -s)'
1271 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1272 echo ' (default: $(INSTALL_HDR_PATH))'; \
1274 @echo 'Static analysers'
1275 @echo ' checkstack - Generate a list of stack hogs'
1276 @echo ' namespacecheck - Name space analysis on compiled kernel'
1277 @echo ' versioncheck - Sanity check on version.h usage'
1278 @echo ' includecheck - Check for duplicate included header files'
1279 @echo ' export_report - List the usages of all exported symbols'
1280 @echo ' headers_check - Sanity check on exported headers'
1281 @echo ' headerdep - Detect inclusion cycles in headers'
1282 @$(MAKE) -f $(srctree)/scripts/Makefile.help checker-help
1284 @echo 'Kernel selftest'
1285 @echo ' kselftest - Build and run kernel selftest (run as root)'
1286 @echo ' Build, install, and boot kernel before'
1287 @echo ' running kselftest on it'
1289 @echo 'Kernel packaging:'
1290 @$(MAKE) $(build)=$(package-dir) help
1292 @echo 'Documentation targets:'
1293 @$(MAKE) -f $(srctree)/Documentation/DocBook/Makefile dochelp
1295 @echo 'Architecture specific targets ($(SRCARCH)):'
1296 @$(if $(archhelp),$(archhelp),\
1297 echo ' No architecture specific help defined for $(SRCARCH)')
1300 $(foreach b, $(boards), \
1301 printf " %-24s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1303 @$(if $(board-dirs), \
1304 $(foreach b, $(board-dirs), \
1305 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1306 printf " %-16s - Show all of the above\\n" help-boards; \
1309 @echo ' make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1310 @echo ' make V=2 [targets] 2 => give reason for rebuild of target'
1311 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1312 @echo ' make C=1 [targets] Check all c source with $$CHECK (sparse by default)'
1313 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1314 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1315 @echo ' make W=n [targets] Enable extra gcc checks, n=1,2,3 where'
1316 @echo ' 1: warnings which may be relevant and do not occur too often'
1317 @echo ' 2: warnings which occur quite often but may still be relevant'
1318 @echo ' 3: more obscure warnings, can most likely be ignored'
1319 @echo ' Multiple levels can be combined with W=12 or W=123'
1321 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1322 @echo 'For further info see the ./README file'
1325 help-board-dirs := $(addprefix help-,$(board-dirs))
1327 help-boards: $(help-board-dirs)
1329 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1331 $(help-board-dirs): help-%:
1332 @echo 'Architecture specific targets ($(SRCARCH) $*):'
1333 @$(if $(boards-per-dir), \
1334 $(foreach b, $(boards-per-dir), \
1335 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1339 # Documentation targets
1340 # ---------------------------------------------------------------------------
1341 %docs: scripts_basic FORCE
1342 $(Q)$(MAKE) $(build)=scripts build_docproc
1343 $(Q)$(MAKE) $(build)=Documentation/DocBook $@
1345 else # KBUILD_EXTMOD
1348 # External module support.
1349 # When building external modules the kernel used as basis is considered
1350 # read-only, and no consistency checks are made and the make
1351 # system is not used on the basis kernel. If updates are required
1352 # in the basis kernel ordinary make commands (without M=...) must
1355 # The following are the only valid targets when building external
1357 # make M=dir clean Delete all automatically generated files
1358 # make M=dir modules Make all modules in specified dir
1359 # make M=dir Same as 'make M=dir modules'
1360 # make M=dir modules_install
1361 # Install the modules built in the module directory
1362 # Assumes install directory is already created
1364 # We are always building modules
1366 PHONY += crmodverdir
1370 PHONY += $(objtree)/Module.symvers
1371 $(objtree)/Module.symvers:
1372 @test -e $(objtree)/Module.symvers || ( \
1374 echo " WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1375 echo " is missing; modules will have no dependencies and modversions."; \
1378 module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
1379 PHONY += $(module-dirs) modules
1380 $(module-dirs): crmodverdir $(objtree)/Module.symvers
1381 $(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@)
1383 modules: $(module-dirs)
1384 @$(kecho) ' Building modules, stage 2.';
1385 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1387 PHONY += modules_install
1388 modules_install: _emodinst_ _emodinst_post
1390 install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1393 $(Q)mkdir -p $(MODLIB)/$(install-dir)
1394 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1396 PHONY += _emodinst_post
1397 _emodinst_post: _emodinst_
1400 clean-dirs := $(addprefix _clean_,$(KBUILD_EXTMOD))
1402 PHONY += $(clean-dirs) clean
1404 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1406 clean: rm-dirs := $(MODVERDIR)
1407 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers
1410 @echo ' Building external modules.'
1411 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1413 @echo ' modules - default target, build the module(s)'
1414 @echo ' modules_install - install the module'
1415 @echo ' clean - remove generated files in module directory only'
1419 PHONY += prepare scripts
1422 endif # KBUILD_EXTMOD
1424 clean: $(clean-dirs)
1427 @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1428 \( -name '*.[oas]' -o -name '*.ko' -o -name '.*.cmd' \
1431 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1432 -o -name '*.symtypes' -o -name 'modules.order' \
1433 -o -name modules.builtin -o -name '.tmp_*.o.*' \
1434 -o -name '*.gcno' \) -type f -print | xargs rm -f
1436 # Generate tags for editors
1437 # ---------------------------------------------------------------------------
1438 quiet_cmd_tags = GEN $@
1439 cmd_tags = $(CONFIG_SHELL) $(srctree)/scripts/tags.sh $@
1441 tags TAGS cscope gtags: FORCE
1444 # Scripts to check various things for consistency
1445 # ---------------------------------------------------------------------------
1447 PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1450 find $(srctree)/* $(RCS_FIND_IGNORE) \
1451 -name '*.[hcS]' -type f -print | sort \
1452 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1455 find $(srctree)/* $(RCS_FIND_IGNORE) \
1456 -name '*.[hcS]' -type f -print | sort \
1457 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1460 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/$@
1463 $(PERL) $(srctree)/scripts/namespace.pl
1466 $(PERL) $(srctree)/scripts/export_report.pl
1468 endif #ifeq ($(config-targets),1)
1469 endif #ifeq ($(mixed-targets),1)
1471 PHONY += checkstack kernelrelease kernelversion image_name
1473 # UML needs a little special treatment here. It wants to use the host
1474 # toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
1475 # else wants $(ARCH), including people doing cross-builds, which means
1476 # that $(SUBARCH) doesn't work here.
1478 CHECKSTACK_ARCH := $(SUBARCH)
1480 CHECKSTACK_ARCH := $(ARCH)
1483 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1484 $(PERL) $(src)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1487 @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1490 @echo $(KERNELVERSION)
1493 @echo $(KBUILD_IMAGE)
1495 # Clear a bunch of variables before executing the submake
1497 $(Q)mkdir -p $(objtree)/tools
1498 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(filter --j% -j,$(MAKEFLAGS))" O=$(O) subdir=tools -C $(src)/tools/
1501 $(Q)mkdir -p $(objtree)/tools
1502 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(filter --j% -j,$(MAKEFLAGS))" O=$(O) subdir=tools -C $(src)/tools/ $*
1505 # ---------------------------------------------------------------------------
1506 # Single targets are compatible with:
1507 # - build with mixed source and output
1508 # - build with separate output dir 'make O=...'
1509 # - external modules
1511 # target-dir => where to store outputfile
1512 # build-dir => directory in kernel source tree to use
1514 ifeq ($(KBUILD_EXTMOD),)
1515 build-dir = $(patsubst %/,%,$(dir $@))
1516 target-dir = $(dir $@)
1518 zap-slash=$(filter-out .,$(patsubst %/,%,$(dir $@)))
1519 build-dir = $(KBUILD_EXTMOD)$(if $(zap-slash),/$(zap-slash))
1520 target-dir = $(if $(KBUILD_EXTMOD),$(dir $<),$(dir $@))
1523 %.s: %.c prepare scripts FORCE
1524 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1525 %.i: %.c prepare scripts FORCE
1526 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1527 %.o: %.c prepare scripts FORCE
1528 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1529 %.lst: %.c prepare scripts FORCE
1530 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1531 %.s: %.S prepare scripts FORCE
1532 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1533 %.o: %.S prepare scripts FORCE
1534 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1535 %.symtypes: %.c prepare scripts FORCE
1536 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1539 /: prepare scripts FORCE
1541 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1542 $(build)=$(build-dir)
1543 # Make sure the latest headers are built for Documentation
1544 Documentation/: headers_install
1545 %/: prepare scripts FORCE
1547 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1548 $(build)=$(build-dir)
1549 %.ko: prepare scripts FORCE
1551 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1552 $(build)=$(build-dir) $(@:.ko=.o)
1553 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1555 # FIXME Should go into a make.lib or something
1556 # ===========================================================================
1558 quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN $(wildcard $(rm-dirs)))
1559 cmd_rmdirs = rm -rf $(rm-dirs)
1561 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
1562 cmd_rmfiles = rm -f $(rm-files)
1564 # Run depmod only if we have System.map and depmod is executable
1565 quiet_cmd_depmod = DEPMOD $(KERNELRELEASE)
1566 cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1567 $(KERNELRELEASE) "$(patsubst y,_,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX))"
1569 # Create temporary dir for module support files
1570 # clean it up only when building all modules
1571 cmd_crmodverdir = $(Q)mkdir -p $(MODVERDIR) \
1572 $(if $(KBUILD_MODULES),; rm -f $(MODVERDIR)/*)
1574 # read all saved command lines
1576 targets := $(wildcard $(sort $(targets)))
1577 cmd_files := $(wildcard .*.cmd $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
1579 ifneq ($(cmd_files),)
1580 $(cmd_files): ; # Do not try to update included dependency files
1581 include $(cmd_files)
1584 endif # skip-makefile
1589 # Declare the contents of the .PHONY variable as phony. We keep that
1590 # information in a variable so we can use it in if_changed and friends.