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))),)
93 ifneq ($(filter s% -s%,$(MAKEFLAGS)),)
99 export quiet Q KBUILD_VERBOSE
101 # kbuild supports saving output files in a separate directory.
102 # To locate output files in a separate directory two syntaxes are supported.
103 # In both cases the working directory must be the root of the kernel src.
105 # Use "make O=dir/to/store/output/files/"
107 # 2) Set KBUILD_OUTPUT
108 # Set the environment variable KBUILD_OUTPUT to point to the directory
109 # where the output files shall be placed.
110 # export KBUILD_OUTPUT=dir/to/store/output/files/
113 # The O= assignment takes precedence over the KBUILD_OUTPUT environment
116 # KBUILD_SRC is set on invocation of make in OBJ directory
117 # KBUILD_SRC is not intended to be used by the regular user (for now)
118 ifeq ($(KBUILD_SRC),)
120 # OK, Make called in directory where kernel src resides
121 # Do we want to locate output files in a separate directory?
122 ifeq ("$(origin O)", "command line")
123 KBUILD_OUTPUT := $(O)
126 # That's our default target when none is given on the command line
130 # Cancel implicit rules on top Makefile
131 $(CURDIR)/Makefile Makefile: ;
133 ifneq ($(words $(subst :, ,$(CURDIR))), 1)
134 $(error main directory cannot contain spaces nor colons)
137 ifneq ($(KBUILD_OUTPUT),)
138 # Invoke a second make in the output directory, passing relevant variables
139 # check that the output directory actually exists
140 saved-output := $(KBUILD_OUTPUT)
141 KBUILD_OUTPUT := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) \
143 $(if $(KBUILD_OUTPUT),, \
144 $(error failed to create output directory "$(saved-output)"))
146 PHONY += $(MAKECMDGOALS) sub-make
148 $(filter-out _all sub-make $(CURDIR)/Makefile, $(MAKECMDGOALS)) _all: sub-make
152 $(Q)$(MAKE) -C $(KBUILD_OUTPUT) KBUILD_SRC=$(CURDIR) \
153 -f $(CURDIR)/Makefile $(filter-out _all sub-make,$(MAKECMDGOALS))
155 # Leave processing to above invocation of make
157 endif # ifneq ($(KBUILD_OUTPUT),)
158 endif # ifeq ($(KBUILD_SRC),)
160 # We process the rest of the Makefile if this is the final invocation of make
161 ifeq ($(skip-makefile),)
163 # Do not print "Entering directory ...",
164 # but we want to display it when entering to the output directory
165 # so that IDEs/editors are able to understand relative filenames.
166 MAKEFLAGS += --no-print-directory
168 # Call a source code checker (by default, "sparse") as part of the
171 # Use 'make C=1' to enable checking of only re-compiled files.
172 # Use 'make C=2' to enable checking of *all* source files, regardless
173 # of whether they are re-compiled or not.
175 # See the file "Documentation/sparse.txt" for more details, including
176 # where to get the "sparse" utility.
178 ifeq ("$(origin C)", "command line")
179 KBUILD_CHECKSRC = $(C)
181 ifndef KBUILD_CHECKSRC
185 # Use make M=dir to specify directory of external module to build
186 # Old syntax make ... SUBDIRS=$PWD is still supported
187 # Setting the environment variable KBUILD_EXTMOD take precedence
189 KBUILD_EXTMOD ?= $(SUBDIRS)
192 ifeq ("$(origin M)", "command line")
193 KBUILD_EXTMOD := $(M)
196 # If building an external module we do not care about the all: rule
197 # but instead _all depend on modules
199 ifeq ($(KBUILD_EXTMOD),)
205 ifeq ($(KBUILD_SRC),)
206 # building in the source tree
209 ifeq ($(KBUILD_SRC)/,$(dir $(CURDIR)))
210 # building in a subdirectory of the source tree
213 srctree := $(KBUILD_SRC)
220 VPATH := $(srctree)$(if $(KBUILD_EXTMOD),:$(KBUILD_EXTMOD))
222 export srctree objtree VPATH
224 # SUBARCH tells the usermode build what the underlying arch is. That is set
225 # first, and if a usermode build is happening, the "ARCH=um" on the command
226 # line overrides the setting of ARCH below. If a native build is happening,
227 # then ARCH is assigned, getting whatever value it gets normally, and
228 # SUBARCH is subsequently ignored.
230 SUBARCH := $(shell uname -m | sed -e s/i.86/x86/ -e s/x86_64/x86/ \
231 -e s/sun4u/sparc64/ \
232 -e s/arm.*/arm/ -e s/sa110/arm/ \
233 -e s/s390x/s390/ -e s/parisc64/parisc/ \
234 -e s/ppc.*/powerpc/ -e s/mips.*/mips/ \
235 -e s/sh[234].*/sh/ -e s/aarch64.*/arm64/ )
237 # Cross compiling and selecting different set of gcc/bin-utils
238 # ---------------------------------------------------------------------------
240 # When performing cross compilation for other architectures ARCH shall be set
241 # to the target architecture. (See arch/* for the possibilities).
242 # ARCH can be set during invocation of make:
244 # Another way is to have ARCH set in the environment.
245 # The default ARCH is the host where make is executed.
247 # CROSS_COMPILE specify the prefix used for all executables used
248 # during compilation. Only gcc and related bin-utils executables
249 # are prefixed with $(CROSS_COMPILE).
250 # CROSS_COMPILE can be set on the command line
251 # make CROSS_COMPILE=ia64-linux-
252 # Alternatively CROSS_COMPILE can be set in the environment.
253 # A third alternative is to store a setting in .config so that plain
254 # "make" in the configured kernel build directory always uses that.
255 # Default value for CROSS_COMPILE is not to prefix executables
256 # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
258 CROSS_COMPILE ?= $(CONFIG_CROSS_COMPILE:"%"=%)
260 # Architecture as present in compile.h
261 UTS_MACHINE := $(ARCH)
264 # Additional ARCH settings for x86
268 ifeq ($(ARCH),x86_64)
272 # Additional ARCH settings for sparc
273 ifeq ($(ARCH),sparc32)
276 ifeq ($(ARCH),sparc64)
280 # Additional ARCH settings for sh
285 # Additional ARCH settings for tile
286 ifeq ($(ARCH),tilepro)
289 ifeq ($(ARCH),tilegx)
293 # Where to locate arch specific headers
294 hdr-arch := $(SRCARCH)
296 KCONFIG_CONFIG ?= .config
297 export KCONFIG_CONFIG
299 # SHELL used by kbuild
300 CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
301 else if [ -x /bin/bash ]; then echo /bin/bash; \
302 else echo sh; fi ; fi)
306 HOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 -fomit-frame-pointer -std=gnu89
309 ifeq ($(shell $(HOSTCC) -v 2>&1 | grep -c "clang version"), 1)
310 HOSTCFLAGS += -Wno-unused-value -Wno-unused-parameter \
311 -Wno-missing-field-initializers -fno-delete-null-pointer-checks
314 # Decide whether to build built-in, modular, or both.
315 # Normally, just do built-in.
320 # If we have only "make modules", don't compile built-in objects.
321 # When we're building modules with modversions, we need to consider
322 # the built-in objects during the descend as well, in order to
323 # make sure the checksums are up to date before we record them.
325 ifeq ($(MAKECMDGOALS),modules)
326 KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
329 # If we have "make <whatever> modules", compile modules
330 # in addition to whatever we do anyway.
331 # Just "make" or "make all" shall build modules as well
333 ifneq ($(filter all _all modules,$(MAKECMDGOALS)),)
337 ifeq ($(MAKECMDGOALS),)
341 export KBUILD_MODULES KBUILD_BUILTIN
342 export KBUILD_CHECKSRC KBUILD_SRC KBUILD_EXTMOD
344 # We need some generic definitions (do not try to remake the file).
345 scripts/Kbuild.include: ;
346 include scripts/Kbuild.include
348 # Make variables (CC, etc...)
349 AS = $(CROSS_COMPILE)as
350 LD = $(CROSS_COMPILE)ld
351 CC = $(CROSS_COMPILE)gcc
353 AR = $(CROSS_COMPILE)ar
354 NM = $(CROSS_COMPILE)nm
355 STRIP = $(CROSS_COMPILE)strip
356 OBJCOPY = $(CROSS_COMPILE)objcopy
357 OBJDUMP = $(CROSS_COMPILE)objdump
359 GENKSYMS = scripts/genksyms/genksyms
360 INSTALLKERNEL := installkernel
361 DEPMOD = /sbin/depmod
366 CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
367 -Wbitwise -Wno-return-void $(CF)
376 # Use USERINCLUDE when you must reference the UAPI directories only.
378 -I$(srctree)/arch/$(hdr-arch)/include/uapi \
379 -I$(objtree)/arch/$(hdr-arch)/include/generated/uapi \
380 -I$(srctree)/include/uapi \
381 -I$(objtree)/include/generated/uapi \
382 -include $(srctree)/include/linux/kconfig.h
384 # Use LINUXINCLUDE when you must reference the include/ directory.
385 # Needed to be compatible with the O= option
387 -I$(srctree)/arch/$(hdr-arch)/include \
388 -I$(objtree)/arch/$(hdr-arch)/include/generated/uapi \
389 -I$(objtree)/arch/$(hdr-arch)/include/generated \
390 $(if $(KBUILD_SRC), -I$(srctree)/include) \
393 LINUXINCLUDE += $(filter-out $(LINUXINCLUDE),$(USERINCLUDE))
395 KBUILD_AFLAGS := -D__ASSEMBLY__
396 KBUILD_CFLAGS := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
397 -fno-strict-aliasing -fno-common \
398 -Werror-implicit-function-declaration \
399 -Wno-format-security \
401 KBUILD_CPPFLAGS := -D__KERNEL__
402 KBUILD_AFLAGS_KERNEL :=
403 KBUILD_CFLAGS_KERNEL :=
404 KBUILD_AFLAGS_MODULE := -DMODULE
405 KBUILD_CFLAGS_MODULE := -DMODULE
406 KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
407 GCC_PLUGINS_CFLAGS :=
409 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
410 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
411 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
413 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
414 export ARCH SRCARCH CONFIG_SHELL HOSTCC HOSTCFLAGS CROSS_COMPILE AS LD CC
415 export CPP AR NM STRIP OBJCOPY OBJDUMP
416 export MAKE AWK GENKSYMS INSTALLKERNEL PERL PYTHON UTS_MACHINE
417 export HOSTCXX HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
419 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS LDFLAGS
420 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
421 export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN
422 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
423 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
424 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
425 export KBUILD_ARFLAGS
427 # When compiling out-of-tree modules, put MODVERDIR in the module
428 # tree rather than in the kernel tree. The kernel tree might
430 export MODVERDIR := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_versions
432 # Files to ignore in find ... statements
434 export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o \
435 -name CVS -o -name .pc -o -name .hg -o -name .git \) \
437 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
438 --exclude CVS --exclude .pc --exclude .hg --exclude .git
440 # ===========================================================================
441 # Rules shared between *config targets and build targets
443 # Basic helpers built in scripts/
444 PHONY += scripts_basic
446 $(Q)$(MAKE) $(build)=scripts/basic
447 $(Q)rm -f .tmp_quiet_recordmcount
449 # To avoid any implicit rule to kick in, define an empty command.
450 scripts/basic/%: scripts_basic ;
452 PHONY += outputmakefile
453 # outputmakefile generates a Makefile in the output directory, if using a
454 # separate output directory. This allows convenient use of make in the
457 ifneq ($(KBUILD_SRC),)
458 $(Q)ln -fsn $(srctree) source
459 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile \
460 $(srctree) $(objtree) $(VERSION) $(PATCHLEVEL)
463 # Support for using generic headers in asm-generic
466 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
467 src=asm obj=arch/$(SRCARCH)/include/generated/asm
468 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
469 src=uapi/asm obj=arch/$(SRCARCH)/include/generated/uapi/asm
471 # To make sure we do not include .config for any of the *config targets
472 # catch them early, and hand them over to scripts/kconfig/Makefile
473 # It is allowed to specify more targets when calling make, including
474 # mixing *config targets and build targets.
475 # For example 'make oldconfig all'.
476 # Detect when mixed targets is specified, and make a second invocation
477 # of make so .config is not included in this case either (for *config).
479 version_h := include/generated/uapi/linux/version.h
480 old_version_h := include/linux/version.h
482 no-dot-config-targets := clean mrproper distclean \
483 cscope gtags TAGS tags help% %docs check% coccicheck \
484 $(version_h) headers_% archheaders archscripts \
485 kernelversion %src-pkg
491 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
492 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
497 ifeq ($(KBUILD_EXTMOD),)
498 ifneq ($(filter config %config,$(MAKECMDGOALS)),)
500 ifneq ($(words $(MAKECMDGOALS)),1)
505 # install and module_install need also be processed one by one
506 ifneq ($(filter install,$(MAKECMDGOALS)),)
507 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
512 ifeq ($(mixed-targets),1)
513 # ===========================================================================
514 # We're called with mixed targets (*config and build targets).
515 # Handle them one by one.
517 PHONY += $(MAKECMDGOALS) __build_one_by_one
519 $(filter-out __build_one_by_one, $(MAKECMDGOALS)): __build_one_by_one
524 for i in $(MAKECMDGOALS); do \
525 $(MAKE) -f $(srctree)/Makefile $$i; \
529 ifeq ($(config-targets),1)
530 # ===========================================================================
531 # *config targets only - make sure prerequisites are updated, and descend
532 # in scripts/kconfig to make the *config target
534 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
535 # KBUILD_DEFCONFIG may point out an alternative default configuration
536 # used for 'make defconfig'
537 include arch/$(SRCARCH)/Makefile
538 export KBUILD_DEFCONFIG KBUILD_KCONFIG
540 config: scripts_basic outputmakefile FORCE
541 $(Q)$(MAKE) $(build)=scripts/kconfig $@
543 %config: scripts_basic outputmakefile FORCE
544 $(Q)$(MAKE) $(build)=scripts/kconfig $@
547 # ===========================================================================
548 # Build targets only - this includes vmlinux, arch specific targets, clean
549 # targets and others. In general all targets except *config targets.
551 ifeq ($(KBUILD_EXTMOD),)
552 # Additional helpers built in scripts/
553 # Carefully list dependencies so we do not try to build scripts twice
556 scripts: scripts_basic include/config/auto.conf include/config/tristate.conf \
557 asm-generic gcc-plugins
558 $(Q)$(MAKE) $(build)=$(@)
560 # Objects we will link into vmlinux / subdirs we need to visit
562 drivers-y := drivers/ sound/ firmware/
567 endif # KBUILD_EXTMOD
569 ifeq ($(dot-config),1)
571 -include include/config/auto.conf
573 ifeq ($(KBUILD_EXTMOD),)
574 # Read in dependencies to all Kconfig* files, make sure to run
575 # oldconfig if changes are detected.
576 -include include/config/auto.conf.cmd
578 # To avoid any implicit rule to kick in, define an empty command
579 $(KCONFIG_CONFIG) include/config/auto.conf.cmd: ;
581 # If .config is newer than include/config/auto.conf, someone tinkered
582 # with it and forgot to run make oldconfig.
583 # if auto.conf.cmd is missing then we are probably in a cleaned tree so
584 # we execute the config step to be sure to catch updated Kconfig files
585 include/config/%.conf: $(KCONFIG_CONFIG) include/config/auto.conf.cmd
586 $(Q)$(MAKE) -f $(srctree)/Makefile silentoldconfig
588 # external modules needs include/generated/autoconf.h and include/config/auto.conf
589 # but do not care if they are up-to-date. Use auto.conf to trigger the test
590 PHONY += include/config/auto.conf
592 include/config/auto.conf:
593 $(Q)test -e include/generated/autoconf.h -a -e $@ || ( \
595 echo >&2 " ERROR: Kernel configuration is invalid."; \
596 echo >&2 " include/generated/autoconf.h or $@ are missing.";\
597 echo >&2 " Run 'make oldconfig && make prepare' on kernel src to fix it."; \
601 endif # KBUILD_EXTMOD
604 # Dummy target needed, because used as prerequisite
605 include/config/auto.conf: ;
606 endif # $(dot-config)
608 # For the kernel to actually contain only the needed exported symbols,
609 # we have to build modules as well to determine what those symbols are.
610 # (this can be evaluated only once include/config/auto.conf has been included)
611 ifdef CONFIG_TRIM_UNUSED_KSYMS
615 # The all: target is the default when no target is given on the
617 # This allow a user to issue only 'make' to build a kernel including modules
618 # Defaults to vmlinux, but the arch makefile usually adds further targets
621 KBUILD_CFLAGS += $(call cc-option,-fno-PIE)
622 KBUILD_AFLAGS += $(call cc-option,-fno-PIE)
623 CFLAGS_GCOV := -fprofile-arcs -ftest-coverage -fno-tree-loop-im $(call cc-disable-warning,maybe-uninitialized,)
624 CFLAGS_KCOV := $(call cc-option,-fsanitize-coverage=trace-pc,)
625 export CFLAGS_GCOV CFLAGS_KCOV
627 # The arch Makefile can set ARCH_{CPP,A,C}FLAGS to override the default
628 # values of the respective KBUILD_* variables
632 include arch/$(SRCARCH)/Makefile
634 KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,)
635 KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,)
636 KBUILD_CFLAGS += $(call cc-disable-warning, format-truncation)
637 KBUILD_CFLAGS += $(call cc-disable-warning, format-overflow)
638 KBUILD_CFLAGS += $(call cc-disable-warning, int-in-bool-context)
639 KBUILD_CFLAGS += $(call cc-disable-warning, attribute-alias)
641 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
642 KBUILD_CFLAGS += $(call cc-option,-ffunction-sections,)
643 KBUILD_CFLAGS += $(call cc-option,-fdata-sections,)
646 ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
647 KBUILD_CFLAGS += $(call cc-option,-Oz,-Os)
648 KBUILD_CFLAGS += $(call cc-disable-warning,maybe-uninitialized,)
650 ifdef CONFIG_PROFILE_ALL_BRANCHES
651 KBUILD_CFLAGS += -O2 $(call cc-disable-warning,maybe-uninitialized,)
657 KBUILD_CFLAGS += $(call cc-ifversion, -lt, 0409, \
658 $(call cc-disable-warning,maybe-uninitialized,))
660 # Tell gcc to never replace conditional load with a non-conditional one
661 KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
663 # check for 'asm goto'
664 ifeq ($(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC) $(KBUILD_CFLAGS)), y)
665 KBUILD_CFLAGS += -DCC_HAVE_ASM_GOTO
666 KBUILD_AFLAGS += -DCC_HAVE_ASM_GOTO
669 include scripts/Makefile.gcc-plugins
671 ifdef CONFIG_READABLE_ASM
672 # Disable optimizations that make assembler listings hard to read.
673 # reorder blocks reorders the control in the function
674 # ipa clone creates specialized cloned functions
675 # partial inlining inlines only parts of functions
676 KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
677 $(call cc-option,-fno-ipa-cp-clone,) \
678 $(call cc-option,-fno-partial-inlining)
681 ifneq ($(CONFIG_FRAME_WARN),0)
682 KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
685 # This selects the stack protector compiler flag. Testing it is delayed
686 # until after .config has been reprocessed, in the prepare-compiler-check
688 ifdef CONFIG_CC_STACKPROTECTOR_REGULAR
689 stackp-flag := -fstack-protector
690 stackp-name := REGULAR
692 ifdef CONFIG_CC_STACKPROTECTOR_STRONG
693 stackp-flag := -fstack-protector-strong
694 stackp-name := STRONG
696 # Force off for distro compilers that enable stack protector by default.
697 stackp-flag := $(call cc-option, -fno-stack-protector)
700 # Find arch-specific stack protector compiler sanity-checking script.
701 ifdef CONFIG_CC_STACKPROTECTOR
702 stackp-path := $(srctree)/scripts/gcc-$(SRCARCH)_$(BITS)-has-stack-protector.sh
703 stackp-check := $(wildcard $(stackp-path))
705 KBUILD_CFLAGS += $(stackp-flag)
707 ifeq ($(cc-name),clang)
708 ifneq ($(CROSS_COMPILE),)
709 CLANG_TARGET := -target $(notdir $(CROSS_COMPILE:%-=%))
710 GCC_TOOLCHAIN := $(realpath $(dir $(shell which $(LD)))/..)
712 ifneq ($(GCC_TOOLCHAIN),)
713 CLANG_GCC_TC := -gcc-toolchain $(GCC_TOOLCHAIN)
715 KBUILD_CFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC)
716 KBUILD_AFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC)
717 KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
718 KBUILD_CFLAGS += $(call cc-disable-warning, unused-variable)
719 KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier)
720 KBUILD_CFLAGS += $(call cc-disable-warning, gnu)
721 # Quiet clang warning: comparison of unsigned expression < 0 is always false
722 KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare)
723 # CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
724 # source of a reference will be _MergedGlobals and not on of the whitelisted names.
725 # See modpost pattern 2
726 KBUILD_CFLAGS += $(call cc-option, -mno-global-merge,)
727 KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior)
728 KBUILD_CFLAGS += $(call cc-option, -no-integrated-as)
729 KBUILD_AFLAGS += $(call cc-option, -no-integrated-as)
732 # These warnings generated too much noise in a regular build.
733 # Use make W=1 to enable them (see scripts/Makefile.build)
734 KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
735 KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
738 ifdef CONFIG_FRAME_POINTER
739 KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
741 # Some targets (ARM with Thumb2, for example), can't be built with frame
742 # pointers. For those, we don't have FUNCTION_TRACER automatically
743 # select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
744 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
745 # -fomit-frame-pointer with FUNCTION_TRACER.
746 ifndef CONFIG_FUNCTION_TRACER
747 KBUILD_CFLAGS += -fomit-frame-pointer
751 KBUILD_CFLAGS += $(call cc-option, -fno-var-tracking-assignments)
753 ifdef CONFIG_DEBUG_INFO
754 ifdef CONFIG_DEBUG_INFO_SPLIT
755 KBUILD_CFLAGS += $(call cc-option, -gsplit-dwarf, -g)
759 KBUILD_AFLAGS += -Wa,-gdwarf-2
761 ifdef CONFIG_DEBUG_INFO_DWARF4
762 KBUILD_CFLAGS += $(call cc-option, -gdwarf-4,)
765 ifdef CONFIG_DEBUG_INFO_REDUCED
766 KBUILD_CFLAGS += $(call cc-option, -femit-struct-debug-baseonly) \
767 $(call cc-option,-fno-var-tracking)
770 ifdef CONFIG_FUNCTION_TRACER
771 ifndef CC_FLAGS_FTRACE
772 CC_FLAGS_FTRACE := -pg
774 export CC_FLAGS_FTRACE
775 ifdef CONFIG_HAVE_FENTRY
776 CC_USING_FENTRY := $(call cc-option, -mfentry -DCC_USING_FENTRY)
778 KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_USING_FENTRY)
779 KBUILD_AFLAGS += $(CC_USING_FENTRY)
780 ifdef CONFIG_DYNAMIC_FTRACE
781 ifdef CONFIG_HAVE_C_RECORDMCOUNT
782 BUILD_C_RECORDMCOUNT := y
783 export BUILD_C_RECORDMCOUNT
788 # We trigger additional mismatches with less inlining
789 ifdef CONFIG_DEBUG_SECTION_MISMATCH
790 KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
793 # arch Makefile may override CC so keep this after arch Makefile is included
794 NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
795 CHECKFLAGS += $(NOSTDINC_FLAGS)
797 # warn about C99 declaration after statement
798 KBUILD_CFLAGS += $(call cc-option,-Wdeclaration-after-statement,)
800 # disable pointer signed / unsigned warnings in gcc 4.0
801 KBUILD_CFLAGS += $(call cc-disable-warning, pointer-sign)
803 # disable invalid "can't wrap" optimizations for signed / pointers
804 KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow)
806 # clang sets -fmerge-all-constants by default as optimization, but this
807 # is non-conforming behavior for C and in fact breaks the kernel, so we
808 # need to disable it here generally.
809 KBUILD_CFLAGS += $(call cc-option,-fno-merge-all-constants)
811 # for gcc -fno-merge-all-constants disables everything, but it is fine
812 # to have actual conforming behavior enabled.
813 KBUILD_CFLAGS += $(call cc-option,-fmerge-constants)
815 # Make sure -fstack-check isn't enabled (like gentoo apparently did)
816 KBUILD_CFLAGS += $(call cc-option,-fno-stack-check,)
818 # conserve stack if available
819 KBUILD_CFLAGS += $(call cc-option,-fconserve-stack)
821 # disallow errors like 'EXPORT_GPL(foo);' with missing header
822 KBUILD_CFLAGS += $(call cc-option,-Werror=implicit-int)
824 # require functions to have arguments in prototypes, not empty 'int foo()'
825 KBUILD_CFLAGS += $(call cc-option,-Werror=strict-prototypes)
827 # Prohibit date/time macros, which would make the build non-deterministic
828 KBUILD_CFLAGS += $(call cc-option,-Werror=date-time)
830 # enforce correct pointer usage
831 KBUILD_CFLAGS += $(call cc-option,-Werror=incompatible-pointer-types)
833 # use the deterministic mode of AR if available
834 KBUILD_ARFLAGS := $(call ar-option,D)
836 include scripts/Makefile.kasan
837 include scripts/Makefile.extrawarn
838 include scripts/Makefile.ubsan
840 # Add any arch overrides and user supplied CPPFLAGS, AFLAGS and CFLAGS as the
842 KBUILD_CPPFLAGS += $(ARCH_CPPFLAGS) $(KCPPFLAGS)
843 KBUILD_AFLAGS += $(ARCH_AFLAGS) $(KAFLAGS)
844 KBUILD_CFLAGS += $(ARCH_CFLAGS) $(KCFLAGS)
846 # Use --build-id when available.
847 LDFLAGS_BUILD_ID = $(patsubst -Wl$(comma)%,%,\
848 $(call cc-ldoption, -Wl$(comma)--build-id,))
849 KBUILD_LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID)
850 LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)
852 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
853 LDFLAGS_vmlinux += $(call ld-option, --gc-sections,)
856 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
857 LDFLAGS_vmlinux += $(call ld-option, -X,)
860 # Default kernel image to build when no specific target is given.
861 # KBUILD_IMAGE may be overruled on the command line or
862 # set in the environment
863 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
865 export KBUILD_IMAGE ?= vmlinux
868 # INSTALL_PATH specifies where to place the updated kernel and system map
869 # images. Default is /boot, but you can set it to other values
870 export INSTALL_PATH ?= /boot
873 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
874 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
875 # an argument if needed. Otherwise it defaults to the kernel install path
877 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
880 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
881 # relocations required by build roots. This is not defined in the
882 # makefile but the argument can be passed to make if needed.
885 MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
889 # INSTALL_MOD_STRIP, if defined, will cause modules to be
890 # stripped after they are installed. If INSTALL_MOD_STRIP is '1', then
891 # the default option --strip-debug will be used. Otherwise,
892 # INSTALL_MOD_STRIP value will be used as the options to the strip command.
894 ifdef INSTALL_MOD_STRIP
895 ifeq ($(INSTALL_MOD_STRIP),1)
896 mod_strip_cmd = $(STRIP) --strip-debug
898 mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
899 endif # INSTALL_MOD_STRIP=1
902 endif # INSTALL_MOD_STRIP
905 # CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
906 # after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
907 # or CONFIG_MODULE_COMPRESS_XZ.
909 mod_compress_cmd = true
910 ifdef CONFIG_MODULE_COMPRESS
911 ifdef CONFIG_MODULE_COMPRESS_GZIP
912 mod_compress_cmd = gzip -n -f
913 endif # CONFIG_MODULE_COMPRESS_GZIP
914 ifdef CONFIG_MODULE_COMPRESS_XZ
915 mod_compress_cmd = xz -f
916 endif # CONFIG_MODULE_COMPRESS_XZ
917 endif # CONFIG_MODULE_COMPRESS
918 export mod_compress_cmd
920 # Select initial ramdisk compression format, default is gzip(1).
921 # This shall be used by the dracut(8) tool while creating an initramfs image.
923 INITRD_COMPRESS-y := gzip
924 INITRD_COMPRESS-$(CONFIG_RD_BZIP2) := bzip2
925 INITRD_COMPRESS-$(CONFIG_RD_LZMA) := lzma
926 INITRD_COMPRESS-$(CONFIG_RD_XZ) := xz
927 INITRD_COMPRESS-$(CONFIG_RD_LZO) := lzo
928 INITRD_COMPRESS-$(CONFIG_RD_LZ4) := lz4
929 # do not export INITRD_COMPRESS, since we didn't actually
930 # choose a sane default compression above.
931 # export INITRD_COMPRESS := $(INITRD_COMPRESS-y)
933 ifdef CONFIG_MODULE_SIG_ALL
934 $(eval $(call config_filename,MODULE_SIG_KEY))
936 mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
943 ifeq ($(KBUILD_EXTMOD),)
944 core-y += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
946 vmlinux-dirs := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
947 $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
948 $(net-y) $(net-m) $(libs-y) $(libs-m) $(virt-y)))
950 vmlinux-alldirs := $(sort $(vmlinux-dirs) $(patsubst %/,%,$(filter %/, \
951 $(init-) $(core-) $(drivers-) $(net-) $(libs-) $(virt-))))
953 init-y := $(patsubst %/, %/built-in.o, $(init-y))
954 core-y := $(patsubst %/, %/built-in.o, $(core-y))
955 drivers-y := $(patsubst %/, %/built-in.o, $(drivers-y))
956 net-y := $(patsubst %/, %/built-in.o, $(net-y))
957 libs-y1 := $(patsubst %/, %/lib.a, $(libs-y))
958 libs-y2 := $(patsubst %/, %/built-in.o, $(libs-y))
959 libs-y := $(libs-y1) $(libs-y2)
960 virt-y := $(patsubst %/, %/built-in.o, $(virt-y))
962 # Externally visible symbols (used by link-vmlinux.sh)
963 export KBUILD_VMLINUX_INIT := $(head-y) $(init-y)
964 export KBUILD_VMLINUX_MAIN := $(core-y) $(libs-y) $(drivers-y) $(net-y) $(virt-y)
965 export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
966 export LDFLAGS_vmlinux
967 # used by scripts/pacmage/Makefile
968 export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) arch Documentation include samples scripts tools)
970 vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_INIT) $(KBUILD_VMLINUX_MAIN)
972 # Include targets which we want to execute sequentially if the rest of the
973 # kernel build went well. If CONFIG_TRIM_UNUSED_KSYMS is set, this might be
974 # evaluated more than once.
975 PHONY += vmlinux_prereq
976 vmlinux_prereq: $(vmlinux-deps) FORCE
977 ifdef CONFIG_HEADERS_CHECK
978 $(Q)$(MAKE) -f $(srctree)/Makefile headers_check
980 ifdef CONFIG_GDB_SCRIPTS
981 $(Q)ln -fsn `cd $(srctree) && /bin/pwd`/scripts/gdb/vmlinux-gdb.py
983 ifdef CONFIG_TRIM_UNUSED_KSYMS
984 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
985 "$(MAKE) -f $(srctree)/Makefile vmlinux"
988 # standalone target for easier testing
989 include/generated/autoksyms.h: FORCE
990 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh true
992 ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
994 # Final link of vmlinux with optional arch pass after final link
996 $(CONFIG_SHELL) $< $(LD) $(LDFLAGS) $(LDFLAGS_vmlinux) ; \
997 $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
999 vmlinux: scripts/link-vmlinux.sh vmlinux_prereq $(vmlinux-deps) FORCE
1000 +$(call if_changed,link-vmlinux)
1002 # Build samples along the rest of the kernel
1003 ifdef CONFIG_SAMPLES
1004 vmlinux-dirs += samples
1007 # The actual objects are generated when descending,
1008 # make sure no implicit rule kicks in
1009 $(sort $(vmlinux-deps)): $(vmlinux-dirs) ;
1011 # Handle descending into subdirectories listed in $(vmlinux-dirs)
1012 # Preset locale variables to speed up the build process. Limit locale
1013 # tweaks to this spot to avoid wrong language settings when running
1014 # make menuconfig etc.
1015 # Error messages still appears in the original language
1017 PHONY += $(vmlinux-dirs)
1018 $(vmlinux-dirs): prepare scripts
1019 $(Q)$(MAKE) $(build)=$@
1021 define filechk_kernel.release
1022 echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1025 # Store (new) KERNELRELEASE string in include/config/kernel.release
1026 include/config/kernel.release: include/config/auto.conf FORCE
1027 $(call filechk,kernel.release)
1030 # Things we need to do before we recursively start building the kernel
1031 # or the modules are listed in "prepare".
1032 # A multi level approach is used. prepareN is processed before prepareN-1.
1033 # archprepare is used in arch Makefiles and when processed asm symlink,
1034 # version.h and scripts_basic is processed / created.
1036 # Listed in dependency order
1037 PHONY += prepare archprepare prepare0 prepare1 prepare2 prepare3
1039 # prepare3 is used to check if we are building in a separate output directory,
1041 # 1) Check that make has not been executed in the kernel src $(srctree)
1042 prepare3: include/config/kernel.release
1043 ifneq ($(KBUILD_SRC),)
1044 @$(kecho) ' Using $(srctree) as source for kernel'
1045 $(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \
1046 echo >&2 " $(srctree) is not clean, please run 'make mrproper'"; \
1047 echo >&2 " in the '$(srctree)' directory.";\
1052 # prepare2 creates a makefile if using a separate output directory.
1053 # From this point forward, .config has been reprocessed, so any rules
1054 # that need to depend on updated CONFIG_* values can be checked here.
1055 prepare2: prepare3 prepare-compiler-check outputmakefile asm-generic
1057 prepare1: prepare2 $(version_h) include/generated/utsrelease.h \
1058 include/config/auto.conf
1061 archprepare: archheaders archscripts prepare1 scripts_basic
1063 prepare0: archprepare gcc-plugins
1064 $(Q)$(MAKE) $(build)=.
1066 # All the preparing..
1067 prepare: prepare0 prepare-objtool
1069 ifdef CONFIG_STACK_VALIDATION
1070 has_libelf := $(call try-run,\
1071 echo "int main() {}" | $(HOSTCC) -xc -o /dev/null -lelf -,1,0)
1072 ifeq ($(has_libelf),1)
1073 objtool_target := tools/objtool FORCE
1075 $(warning "Cannot use CONFIG_STACK_VALIDATION, please install libelf-dev, libelf-devel or elfutils-libelf-devel")
1076 SKIP_STACK_VALIDATION := 1
1077 export SKIP_STACK_VALIDATION
1081 PHONY += prepare-objtool
1082 prepare-objtool: $(objtool_target)
1084 # Check for CONFIG flags that require compiler support. Abort the build
1085 # after .config has been processed, but before the kernel build starts.
1087 # For security-sensitive CONFIG options, we don't want to fallback and/or
1088 # silently change which compiler flags will be used, since that leads to
1089 # producing kernels with different security feature characteristics
1090 # depending on the compiler used. (For example, "But I selected
1091 # CC_STACKPROTECTOR_STRONG! Why did it build with _REGULAR?!")
1092 PHONY += prepare-compiler-check
1093 prepare-compiler-check: FORCE
1094 # Make sure compiler supports requested stack protector flag.
1096 ifeq ($(call cc-option, $(stackp-flag)),)
1097 @echo Cannot use CONFIG_CC_STACKPROTECTOR_$(stackp-name): \
1098 $(stackp-flag) not supported by compiler >&2 && exit 1
1101 # Make sure compiler does not have buggy stack-protector support.
1103 ifneq ($(shell $(CONFIG_SHELL) $(stackp-check) $(CC) $(KBUILD_CPPFLAGS) $(biarch)),y)
1104 @echo Cannot use CONFIG_CC_STACKPROTECTOR_$(stackp-name): \
1105 $(stackp-flag) available but compiler is broken >&2 && exit 1
1110 # Generate some files
1111 # ---------------------------------------------------------------------------
1113 # KERNELRELEASE can change from a few different places, meaning version.h
1114 # needs to be updated, so this check is forced on all builds
1117 define filechk_utsrelease.h
1118 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1119 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1122 (echo \#define UTS_RELEASE \"$(KERNELRELEASE)\";)
1125 define filechk_version.h
1126 (echo \#define LINUX_VERSION_CODE $(shell \
1127 expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1128 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))';)
1131 $(version_h): $(srctree)/Makefile FORCE
1132 $(call filechk,version.h)
1133 $(Q)rm -f $(old_version_h)
1135 include/generated/utsrelease.h: include/config/kernel.release FORCE
1136 $(call filechk,utsrelease.h)
1140 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1141 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1143 # ---------------------------------------------------------------------------
1145 INSTALL_FW_PATH=$(INSTALL_MOD_PATH)/lib/firmware
1146 export INSTALL_FW_PATH
1148 PHONY += firmware_install
1150 @mkdir -p $(objtree)/firmware
1151 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_install
1153 # ---------------------------------------------------------------------------
1156 #Default location for installed headers
1157 export INSTALL_HDR_PATH = $(objtree)/usr
1159 # If we do an all arch process set dst to asm-$(hdr-arch)
1160 hdr-dst = $(if $(KBUILD_HEADERS), dst=include/asm-$(hdr-arch), dst=include/asm)
1162 PHONY += archheaders
1165 PHONY += archscripts
1169 __headers: $(version_h) scripts_basic asm-generic archheaders archscripts
1170 $(Q)$(MAKE) $(build)=scripts build_unifdef
1172 PHONY += headers_install_all
1173 headers_install_all:
1174 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh install
1176 PHONY += headers_install
1177 headers_install: __headers
1178 $(if $(wildcard $(srctree)/arch/$(hdr-arch)/include/uapi/asm/Kbuild),, \
1179 $(error Headers not exportable for the $(SRCARCH) architecture))
1180 $(Q)$(MAKE) $(hdr-inst)=include/uapi
1181 $(Q)$(MAKE) $(hdr-inst)=arch/$(hdr-arch)/include/uapi/asm $(hdr-dst)
1183 PHONY += headers_check_all
1184 headers_check_all: headers_install_all
1185 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh check
1187 PHONY += headers_check
1188 headers_check: headers_install
1189 $(Q)$(MAKE) $(hdr-inst)=include/uapi HDRCHECK=1
1190 $(Q)$(MAKE) $(hdr-inst)=arch/$(hdr-arch)/include/uapi/asm $(hdr-dst) HDRCHECK=1
1192 # ---------------------------------------------------------------------------
1197 $(Q)$(MAKE) -C tools/testing/selftests run_tests
1200 $(Q)$(MAKE) -C tools/testing/selftests clean
1202 PHONY += kselftest-merge
1204 $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1205 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/kconfig/merge_config.sh \
1206 -m $(objtree)/.config \
1207 $(srctree)/tools/testing/selftests/*/config
1208 +$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1210 # ---------------------------------------------------------------------------
1213 ifdef CONFIG_MODULES
1215 # By default, build modules as well
1221 # A module can be listed more than once in obj-m resulting in
1222 # duplicate lines in modules.order files. Those are removed
1223 # using awk while concatenating to the final file.
1226 modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux) modules.builtin
1227 $(Q)$(AWK) '!x[$$0]++' $(vmlinux-dirs:%=$(objtree)/%/modules.order) > $(objtree)/modules.order
1228 @$(kecho) ' Building modules, stage 2.';
1229 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1230 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_modbuild
1232 modules.builtin: $(vmlinux-dirs:%=%/modules.builtin)
1233 $(Q)$(AWK) '!x[$$0]++' $^ > $(objtree)/modules.builtin
1235 %/modules.builtin: include/config/auto.conf
1236 $(Q)$(MAKE) $(modbuiltin)=$*
1239 # Target to prepare building external modules
1240 PHONY += modules_prepare
1241 modules_prepare: prepare scripts
1243 # Target to install modules
1244 PHONY += modules_install
1245 modules_install: _modinst_ _modinst_post
1249 @rm -rf $(MODLIB)/kernel
1250 @rm -f $(MODLIB)/source
1251 @mkdir -p $(MODLIB)/kernel
1252 @ln -s `cd $(srctree) && /bin/pwd` $(MODLIB)/source
1253 @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
1254 rm -f $(MODLIB)/build ; \
1255 ln -s $(CURDIR) $(MODLIB)/build ; \
1257 @cp -f $(objtree)/modules.order $(MODLIB)/
1258 @cp -f $(objtree)/modules.builtin $(MODLIB)/
1259 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1261 # This depmod is only for convenience to give the initial
1262 # boot a modules.dep even before / is mounted read-write. However the
1263 # boot script depmod is the master version.
1264 PHONY += _modinst_post
1265 _modinst_post: _modinst_
1266 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_modinst
1269 ifeq ($(CONFIG_MODULE_SIG), y)
1270 PHONY += modules_sign
1272 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1275 else # CONFIG_MODULES
1277 # Modules not configured
1278 # ---------------------------------------------------------------------------
1280 PHONY += modules modules_install
1281 modules modules_install:
1283 @echo >&2 "The present kernel configuration has modules disabled."
1284 @echo >&2 "Type 'make config' and enable loadable module support."
1285 @echo >&2 "Then build a kernel with module support enabled."
1289 endif # CONFIG_MODULES
1292 # Cleaning is done on three levels.
1293 # make clean Delete most generated files
1294 # Leave enough to build external modules
1295 # make mrproper Delete the current configuration, and all generated files
1296 # make distclean Remove editor backup files, patch leftover files and the like
1298 # Directories & files removed with 'make clean'
1299 CLEAN_DIRS += $(MODVERDIR)
1301 # Directories & files removed with 'make mrproper'
1302 MRPROPER_DIRS += include/config usr/include include/generated \
1303 arch/*/include/generated .tmp_objdiff
1304 MRPROPER_FILES += .config .config.old .version .old_version \
1305 Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS \
1306 signing_key.pem signing_key.priv signing_key.x509 \
1307 x509.genkey extra_certificates signing_key.x509.keyid \
1308 signing_key.x509.signer vmlinux-gdb.py
1310 # clean - Delete most, but leave enough to build external modules
1312 clean: rm-dirs := $(CLEAN_DIRS)
1313 clean: rm-files := $(CLEAN_FILES)
1314 clean-dirs := $(addprefix _clean_, . $(vmlinux-alldirs) Documentation samples)
1316 PHONY += $(clean-dirs) clean archclean vmlinuxclean
1318 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1321 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1322 $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1324 clean: archclean vmlinuxclean
1326 # mrproper - Delete all generated files, including .config
1328 mrproper: rm-dirs := $(wildcard $(MRPROPER_DIRS))
1329 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1330 mrproper-dirs := $(addprefix _mrproper_,Documentation/DocBook scripts)
1332 PHONY += $(mrproper-dirs) mrproper archmrproper
1334 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1336 mrproper: clean archmrproper $(mrproper-dirs)
1345 @find $(srctree) $(RCS_FIND_IGNORE) \
1346 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1347 -o -name '*.bak' -o -name '#*#' -o -name '.*.orig' \
1348 -o -name '.*.rej' -o -name '*%' -o -name 'core' \) \
1349 -type f -print | xargs rm -f
1352 # Packaging of the kernel to various formats
1353 # ---------------------------------------------------------------------------
1354 # rpm target kept for backward compatibility
1355 package-dir := scripts/package
1358 $(Q)$(MAKE) $(build)=$(package-dir) $@
1359 %pkg: include/config/kernel.release FORCE
1360 $(Q)$(MAKE) $(build)=$(package-dir) $@
1361 rpm: include/config/kernel.release FORCE
1362 $(Q)$(MAKE) $(build)=$(package-dir) $@
1365 # Brief documentation of the typical targets used
1366 # ---------------------------------------------------------------------------
1368 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1369 boards := $(sort $(notdir $(boards)))
1370 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1371 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1375 @echo 'Cleaning targets:'
1376 @echo ' clean - Remove most generated files but keep the config and'
1377 @echo ' enough build support to build external modules'
1378 @echo ' mrproper - Remove all generated files + config + various backup files'
1379 @echo ' distclean - mrproper + remove editor backup and patch files'
1381 @echo 'Configuration targets:'
1382 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1384 @echo 'Other generic targets:'
1385 @echo ' all - Build all targets marked with [*]'
1386 @echo '* vmlinux - Build the bare kernel'
1387 @echo '* modules - Build all modules'
1388 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1389 @echo ' firmware_install- Install all firmware to INSTALL_FW_PATH'
1390 @echo ' (default: $$(INSTALL_MOD_PATH)/lib/firmware)'
1391 @echo ' dir/ - Build all files in dir and below'
1392 @echo ' dir/file.[ois] - Build specified target only'
1393 @echo ' dir/file.ll - Build the LLVM assembly file'
1394 @echo ' (requires compiler support for LLVM assembly generation)'
1395 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1396 @echo ' (requires a recent binutils and recent build (System.map))'
1397 @echo ' dir/file.ko - Build module including final link'
1398 @echo ' modules_prepare - Set up for building external modules'
1399 @echo ' tags/TAGS - Generate tags file for editors'
1400 @echo ' cscope - Generate cscope index'
1401 @echo ' gtags - Generate GNU GLOBAL index'
1402 @echo ' kernelrelease - Output the release version string (use with make -s)'
1403 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1404 @echo ' image_name - Output the image name (use with make -s)'
1405 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1406 echo ' (default: $(INSTALL_HDR_PATH))'; \
1408 @echo 'Static analysers'
1409 @echo ' checkstack - Generate a list of stack hogs'
1410 @echo ' namespacecheck - Name space analysis on compiled kernel'
1411 @echo ' versioncheck - Sanity check on version.h usage'
1412 @echo ' includecheck - Check for duplicate included header files'
1413 @echo ' export_report - List the usages of all exported symbols'
1414 @echo ' headers_check - Sanity check on exported headers'
1415 @echo ' headerdep - Detect inclusion cycles in headers'
1416 @$(MAKE) -f $(srctree)/scripts/Makefile.help checker-help
1418 @echo 'Kernel selftest'
1419 @echo ' kselftest - Build and run kernel selftest (run as root)'
1420 @echo ' Build, install, and boot kernel before'
1421 @echo ' running kselftest on it'
1422 @echo ' kselftest-clean - Remove all generated kselftest files'
1423 @echo ' kselftest-merge - Merge all the config dependencies of kselftest to existed'
1426 @echo 'Kernel packaging:'
1427 @$(MAKE) $(build)=$(package-dir) help
1429 @echo 'Documentation targets:'
1430 @$(MAKE) -f $(srctree)/Documentation/Makefile.sphinx dochelp
1432 @$(MAKE) -f $(srctree)/Documentation/DocBook/Makefile dochelp
1434 @echo 'Architecture specific targets ($(SRCARCH)):'
1435 @$(if $(archhelp),$(archhelp),\
1436 echo ' No architecture specific help defined for $(SRCARCH)')
1439 $(foreach b, $(boards), \
1440 printf " %-24s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1442 @$(if $(board-dirs), \
1443 $(foreach b, $(board-dirs), \
1444 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1445 printf " %-16s - Show all of the above\\n" help-boards; \
1448 @echo ' make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1449 @echo ' make V=2 [targets] 2 => give reason for rebuild of target'
1450 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1451 @echo ' make C=1 [targets] Check all c source with $$CHECK (sparse by default)'
1452 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1453 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1454 @echo ' make W=n [targets] Enable extra gcc checks, n=1,2,3 where'
1455 @echo ' 1: warnings which may be relevant and do not occur too often'
1456 @echo ' 2: warnings which occur quite often but may still be relevant'
1457 @echo ' 3: more obscure warnings, can most likely be ignored'
1458 @echo ' Multiple levels can be combined with W=12 or W=123'
1460 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1461 @echo 'For further info see the ./README file'
1464 help-board-dirs := $(addprefix help-,$(board-dirs))
1466 help-boards: $(help-board-dirs)
1468 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1470 $(help-board-dirs): help-%:
1471 @echo 'Architecture specific targets ($(SRCARCH) $*):'
1472 @$(if $(boards-per-dir), \
1473 $(foreach b, $(boards-per-dir), \
1474 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1478 # Documentation targets
1479 # ---------------------------------------------------------------------------
1480 DOC_TARGETS := xmldocs sgmldocs psdocs latexdocs pdfdocs htmldocs mandocs installmandocs epubdocs cleandocs
1481 PHONY += $(DOC_TARGETS)
1482 $(DOC_TARGETS): scripts_basic FORCE
1483 $(Q)$(MAKE) $(build)=scripts build_docproc build_check-lc_ctype
1484 $(Q)$(MAKE) $(build)=Documentation -f $(srctree)/Documentation/Makefile.sphinx $@
1485 $(Q)$(MAKE) $(build)=Documentation/DocBook $@
1487 else # KBUILD_EXTMOD
1490 # External module support.
1491 # When building external modules the kernel used as basis is considered
1492 # read-only, and no consistency checks are made and the make
1493 # system is not used on the basis kernel. If updates are required
1494 # in the basis kernel ordinary make commands (without M=...) must
1497 # The following are the only valid targets when building external
1499 # make M=dir clean Delete all automatically generated files
1500 # make M=dir modules Make all modules in specified dir
1501 # make M=dir Same as 'make M=dir modules'
1502 # make M=dir modules_install
1503 # Install the modules built in the module directory
1504 # Assumes install directory is already created
1506 # We are always building modules
1508 PHONY += crmodverdir
1512 PHONY += $(objtree)/Module.symvers
1513 $(objtree)/Module.symvers:
1514 @test -e $(objtree)/Module.symvers || ( \
1516 echo " WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1517 echo " is missing; modules will have no dependencies and modversions."; \
1520 module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
1521 PHONY += $(module-dirs) modules
1522 $(module-dirs): crmodverdir $(objtree)/Module.symvers
1523 $(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@)
1525 modules: $(module-dirs)
1526 @$(kecho) ' Building modules, stage 2.';
1527 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1529 PHONY += modules_install
1530 modules_install: _emodinst_ _emodinst_post
1532 install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1535 $(Q)mkdir -p $(MODLIB)/$(install-dir)
1536 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1538 PHONY += _emodinst_post
1539 _emodinst_post: _emodinst_
1542 clean-dirs := $(addprefix _clean_,$(KBUILD_EXTMOD))
1544 PHONY += $(clean-dirs) clean
1546 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1548 clean: rm-dirs := $(MODVERDIR)
1549 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers
1553 @echo ' Building external modules.'
1554 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1556 @echo ' modules - default target, build the module(s)'
1557 @echo ' modules_install - install the module'
1558 @echo ' clean - remove generated files in module directory only'
1562 PHONY += prepare scripts
1565 endif # KBUILD_EXTMOD
1567 clean: $(clean-dirs)
1570 @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1571 \( -name '*.[oas]' -o -name '*.ko' -o -name '.*.cmd' \
1575 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1576 -o -name '*.symtypes' -o -name 'modules.order' \
1577 -o -name modules.builtin -o -name '.tmp_*.o.*' \
1578 -o -name '*.c.[012]*.*' \
1580 -o -name '*.gcno' \) -type f -print | xargs rm -f
1582 # Generate tags for editors
1583 # ---------------------------------------------------------------------------
1584 quiet_cmd_tags = GEN $@
1585 cmd_tags = $(CONFIG_SHELL) $(srctree)/scripts/tags.sh $@
1587 tags TAGS cscope gtags: FORCE
1590 # Scripts to check various things for consistency
1591 # ---------------------------------------------------------------------------
1593 PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1596 find $(srctree)/* $(RCS_FIND_IGNORE) \
1597 -name '*.[hcS]' -type f -print | sort \
1598 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1601 find $(srctree)/* $(RCS_FIND_IGNORE) \
1602 -name '*.[hcS]' -type f -print | sort \
1603 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1606 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/$@
1609 $(PERL) $(srctree)/scripts/namespace.pl
1612 $(PERL) $(srctree)/scripts/export_report.pl
1614 endif #ifeq ($(config-targets),1)
1615 endif #ifeq ($(mixed-targets),1)
1617 PHONY += checkstack kernelrelease kernelversion image_name
1619 # UML needs a little special treatment here. It wants to use the host
1620 # toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
1621 # else wants $(ARCH), including people doing cross-builds, which means
1622 # that $(SUBARCH) doesn't work here.
1624 CHECKSTACK_ARCH := $(SUBARCH)
1626 CHECKSTACK_ARCH := $(ARCH)
1629 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1630 $(PERL) $(src)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1633 @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1636 @echo $(KERNELVERSION)
1639 @echo $(KBUILD_IMAGE)
1641 # Clear a bunch of variables before executing the submake
1643 $(Q)mkdir -p $(objtree)/tools
1644 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(shell cd $(objtree) && /bin/pwd) subdir=tools -C $(src)/tools/
1647 $(Q)mkdir -p $(objtree)/tools
1648 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(shell cd $(objtree) && /bin/pwd) subdir=tools -C $(src)/tools/ $*
1651 # ---------------------------------------------------------------------------
1652 # Single targets are compatible with:
1653 # - build with mixed source and output
1654 # - build with separate output dir 'make O=...'
1655 # - external modules
1657 # target-dir => where to store outputfile
1658 # build-dir => directory in kernel source tree to use
1660 ifeq ($(KBUILD_EXTMOD),)
1661 build-dir = $(patsubst %/,%,$(dir $@))
1662 target-dir = $(dir $@)
1664 zap-slash=$(filter-out .,$(patsubst %/,%,$(dir $@)))
1665 build-dir = $(KBUILD_EXTMOD)$(if $(zap-slash),/$(zap-slash))
1666 target-dir = $(if $(KBUILD_EXTMOD),$(dir $<),$(dir $@))
1669 %.s: %.c prepare scripts FORCE
1670 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1671 %.i: %.c prepare scripts FORCE
1672 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1673 %.o: %.c prepare scripts FORCE
1674 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1675 %.lst: %.c prepare scripts FORCE
1676 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1677 %.s: %.S prepare scripts FORCE
1678 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1679 %.o: %.S prepare scripts FORCE
1680 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1681 %.symtypes: %.c prepare scripts FORCE
1682 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1683 %.ll: %.c prepare scripts FORCE
1684 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1687 /: prepare scripts FORCE
1689 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1690 $(build)=$(build-dir)
1691 # Make sure the latest headers are built for Documentation
1692 Documentation/ samples/: headers_install
1693 %/: prepare scripts FORCE
1695 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1696 $(build)=$(build-dir)
1697 %.ko: prepare scripts FORCE
1699 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1700 $(build)=$(build-dir) $(@:.ko=.o)
1701 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1703 # FIXME Should go into a make.lib or something
1704 # ===========================================================================
1706 quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN $(wildcard $(rm-dirs)))
1707 cmd_rmdirs = rm -rf $(rm-dirs)
1709 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
1710 cmd_rmfiles = rm -f $(rm-files)
1712 # Run depmod only if we have System.map and depmod is executable
1713 quiet_cmd_depmod = DEPMOD $(KERNELRELEASE)
1714 cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1715 $(KERNELRELEASE) "$(patsubst y,_,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX))"
1717 # Create temporary dir for module support files
1718 # clean it up only when building all modules
1719 cmd_crmodverdir = $(Q)mkdir -p $(MODVERDIR) \
1720 $(if $(KBUILD_MODULES),; rm -f $(MODVERDIR)/*)
1722 # read all saved command lines
1724 targets := $(wildcard $(sort $(targets)))
1725 cmd_files := $(wildcard .*.cmd $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
1727 ifneq ($(cmd_files),)
1728 $(cmd_files): ; # Do not try to update included dependency files
1729 include $(cmd_files)
1732 endif # skip-makefile
1737 # Declare the contents of the .PHONY variable as phony. We keep that
1738 # information in a variable so we can use it in if_changed and friends.