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 ($(skip-makefile),)
163 # Do not print "Entering directory ...",
164 # but we want to display it when entering to the output directory
165 # so that IDEs/editors are able to understand relative filenames.
166 MAKEFLAGS += --no-print-directory
168 # Call a source code checker (by default, "sparse") as part of the
171 # Use 'make C=1' to enable checking of only re-compiled files.
172 # Use 'make C=2' to enable checking of *all* source files, regardless
173 # of whether they are re-compiled or not.
175 # See the file "Documentation/dev-tools/sparse.rst" for more details,
176 # including where to get the "sparse" utility.
178 ifeq ("$(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)
375 CFLAGS_GCOV := -fprofile-arcs -ftest-coverage -fno-tree-loop-im $(call cc-disable-warning,maybe-uninitialized,)
376 CFLAGS_KCOV := $(call cc-option,-fsanitize-coverage=trace-pc,)
379 # Use USERINCLUDE when you must reference the UAPI directories only.
381 -I$(srctree)/arch/$(hdr-arch)/include/uapi \
382 -I$(objtree)/arch/$(hdr-arch)/include/generated/uapi \
383 -I$(srctree)/include/uapi \
384 -I$(objtree)/include/generated/uapi \
385 -include $(srctree)/include/linux/kconfig.h
387 # Use LINUXINCLUDE when you must reference the include/ directory.
388 # Needed to be compatible with the O= option
390 -I$(srctree)/arch/$(hdr-arch)/include \
391 -I$(objtree)/arch/$(hdr-arch)/include/generated/uapi \
392 -I$(objtree)/arch/$(hdr-arch)/include/generated \
393 $(if $(KBUILD_SRC), -I$(srctree)/include) \
396 LINUXINCLUDE += $(filter-out $(LINUXINCLUDE),$(USERINCLUDE))
398 KBUILD_CPPFLAGS := -D__KERNEL__
400 KBUILD_CFLAGS := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
401 -fno-strict-aliasing -fno-common \
402 -Werror-implicit-function-declaration \
403 -Wno-format-security \
404 -std=gnu89 $(call cc-option,-fno-PIE)
407 KBUILD_AFLAGS_KERNEL :=
408 KBUILD_CFLAGS_KERNEL :=
409 KBUILD_AFLAGS := -D__ASSEMBLY__ $(call cc-option,-fno-PIE)
410 KBUILD_AFLAGS_MODULE := -DMODULE
411 KBUILD_CFLAGS_MODULE := -DMODULE
412 KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
414 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
415 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
416 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
418 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
419 export ARCH SRCARCH CONFIG_SHELL HOSTCC HOSTCFLAGS CROSS_COMPILE AS LD CC
420 export CPP AR NM STRIP OBJCOPY OBJDUMP
421 export MAKE AWK GENKSYMS INSTALLKERNEL PERL PYTHON UTS_MACHINE
422 export HOSTCXX HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
424 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS LDFLAGS
425 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE CFLAGS_GCOV CFLAGS_KCOV CFLAGS_KASAN CFLAGS_UBSAN
426 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
427 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
428 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
429 export KBUILD_ARFLAGS
431 # When compiling out-of-tree modules, put MODVERDIR in the module
432 # tree rather than in the kernel tree. The kernel tree might
434 export MODVERDIR := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_versions
436 # Files to ignore in find ... statements
438 export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o \
439 -name CVS -o -name .pc -o -name .hg -o -name .git \) \
441 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
442 --exclude CVS --exclude .pc --exclude .hg --exclude .git
444 # ===========================================================================
445 # Rules shared between *config targets and build targets
447 # Basic helpers built in scripts/
448 PHONY += scripts_basic
450 $(Q)$(MAKE) $(build)=scripts/basic
451 $(Q)rm -f .tmp_quiet_recordmcount
453 # To avoid any implicit rule to kick in, define an empty command.
454 scripts/basic/%: scripts_basic ;
456 PHONY += outputmakefile
457 # outputmakefile generates a Makefile in the output directory, if using a
458 # separate output directory. This allows convenient use of make in the
461 ifneq ($(KBUILD_SRC),)
462 $(Q)ln -fsn $(srctree) source
463 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile \
464 $(srctree) $(objtree) $(VERSION) $(PATCHLEVEL)
467 # Support for using generic headers in asm-generic
470 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
471 src=asm obj=arch/$(SRCARCH)/include/generated/asm
472 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
473 src=uapi/asm obj=arch/$(SRCARCH)/include/generated/uapi/asm
475 # To make sure we do not include .config for any of the *config targets
476 # catch them early, and hand them over to scripts/kconfig/Makefile
477 # It is allowed to specify more targets when calling make, including
478 # mixing *config targets and build targets.
479 # For example 'make oldconfig all'.
480 # Detect when mixed targets is specified, and make a second invocation
481 # of make so .config is not included in this case either (for *config).
483 version_h := include/generated/uapi/linux/version.h
484 old_version_h := include/linux/version.h
486 no-dot-config-targets := clean mrproper distclean \
487 cscope gtags TAGS tags help% %docs check% coccicheck \
488 $(version_h) headers_% archheaders archscripts \
489 kernelversion %src-pkg
495 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
496 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
501 ifeq ($(KBUILD_EXTMOD),)
502 ifneq ($(filter config %config,$(MAKECMDGOALS)),)
504 ifneq ($(words $(MAKECMDGOALS)),1)
509 # install and module_install need also be processed one by one
510 ifneq ($(filter install,$(MAKECMDGOALS)),)
511 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
516 ifeq ($(mixed-targets),1)
517 # ===========================================================================
518 # We're called with mixed targets (*config and build targets).
519 # Handle them one by one.
521 PHONY += $(MAKECMDGOALS) __build_one_by_one
523 $(filter-out __build_one_by_one, $(MAKECMDGOALS)): __build_one_by_one
528 for i in $(MAKECMDGOALS); do \
529 $(MAKE) -f $(srctree)/Makefile $$i; \
533 ifeq ($(config-targets),1)
534 # ===========================================================================
535 # *config targets only - make sure prerequisites are updated, and descend
536 # in scripts/kconfig to make the *config target
538 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
539 # KBUILD_DEFCONFIG may point out an alternative default configuration
540 # used for 'make defconfig'
541 include arch/$(SRCARCH)/Makefile
542 export KBUILD_DEFCONFIG KBUILD_KCONFIG
544 config: scripts_basic outputmakefile FORCE
545 $(Q)$(MAKE) $(build)=scripts/kconfig $@
547 %config: scripts_basic outputmakefile FORCE
548 $(Q)$(MAKE) $(build)=scripts/kconfig $@
551 # ===========================================================================
552 # Build targets only - this includes vmlinux, arch specific targets, clean
553 # targets and others. In general all targets except *config targets.
555 ifeq ($(KBUILD_EXTMOD),)
556 # Additional helpers built in scripts/
557 # Carefully list dependencies so we do not try to build scripts twice
560 scripts: scripts_basic include/config/auto.conf include/config/tristate.conf \
561 asm-generic gcc-plugins
562 $(Q)$(MAKE) $(build)=$(@)
564 # Objects we will link into vmlinux / subdirs we need to visit
566 drivers-y := drivers/ sound/ firmware/
571 endif # KBUILD_EXTMOD
573 ifeq ($(dot-config),1)
575 -include include/config/auto.conf
577 ifeq ($(KBUILD_EXTMOD),)
578 # Read in dependencies to all Kconfig* files, make sure to run
579 # oldconfig if changes are detected.
580 -include include/config/auto.conf.cmd
582 # To avoid any implicit rule to kick in, define an empty command
583 $(KCONFIG_CONFIG) include/config/auto.conf.cmd: ;
585 # If .config is newer than include/config/auto.conf, someone tinkered
586 # with it and forgot to run make oldconfig.
587 # if auto.conf.cmd is missing then we are probably in a cleaned tree so
588 # we execute the config step to be sure to catch updated Kconfig files
589 include/config/%.conf: $(KCONFIG_CONFIG) include/config/auto.conf.cmd
590 $(Q)$(MAKE) -f $(srctree)/Makefile silentoldconfig
592 # external modules needs include/generated/autoconf.h and include/config/auto.conf
593 # but do not care if they are up-to-date. Use auto.conf to trigger the test
594 PHONY += include/config/auto.conf
596 include/config/auto.conf:
597 $(Q)test -e include/generated/autoconf.h -a -e $@ || ( \
599 echo >&2 " ERROR: Kernel configuration is invalid."; \
600 echo >&2 " include/generated/autoconf.h or $@ are missing.";\
601 echo >&2 " Run 'make oldconfig && make prepare' on kernel src to fix it."; \
605 endif # KBUILD_EXTMOD
608 # Dummy target needed, because used as prerequisite
609 include/config/auto.conf: ;
610 endif # $(dot-config)
612 # For the kernel to actually contain only the needed exported symbols,
613 # we have to build modules as well to determine what those symbols are.
614 # (this can be evaluated only once include/config/auto.conf has been included)
615 ifdef CONFIG_TRIM_UNUSED_KSYMS
619 # The all: target is the default when no target is given on the
621 # This allow a user to issue only 'make' to build a kernel including modules
622 # Defaults to vmlinux, but the arch makefile usually adds further targets
625 # The arch Makefile can set ARCH_{CPP,A,C}FLAGS to override the default
626 # values of the respective KBUILD_* variables
630 include arch/$(SRCARCH)/Makefile
632 KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,)
633 KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,)
635 ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
636 KBUILD_CFLAGS += $(call cc-option,-Oz,-Os)
637 KBUILD_CFLAGS += $(call cc-disable-warning,maybe-uninitialized,)
639 ifdef CONFIG_PROFILE_ALL_BRANCHES
640 KBUILD_CFLAGS += -O2 $(call cc-disable-warning,maybe-uninitialized,)
646 KBUILD_CFLAGS += $(call cc-ifversion, -lt, 0409, \
647 $(call cc-disable-warning,maybe-uninitialized,))
649 # Tell gcc to never replace conditional load with a non-conditional one
650 KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
652 # check for 'asm goto'
653 ifeq ($(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC) $(KBUILD_CFLAGS)), y)
654 KBUILD_CFLAGS += -DCC_HAVE_ASM_GOTO
655 KBUILD_AFLAGS += -DCC_HAVE_ASM_GOTO
658 include scripts/Makefile.gcc-plugins
660 ifdef CONFIG_READABLE_ASM
661 # Disable optimizations that make assembler listings hard to read.
662 # reorder blocks reorders the control in the function
663 # ipa clone creates specialized cloned functions
664 # partial inlining inlines only parts of functions
665 KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
666 $(call cc-option,-fno-ipa-cp-clone,) \
667 $(call cc-option,-fno-partial-inlining)
670 ifneq ($(CONFIG_FRAME_WARN),0)
671 KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
674 # This selects the stack protector compiler flag. Testing it is delayed
675 # until after .config has been reprocessed, in the prepare-compiler-check
677 ifdef CONFIG_CC_STACKPROTECTOR_REGULAR
678 stackp-flag := -fstack-protector
679 stackp-name := REGULAR
681 ifdef CONFIG_CC_STACKPROTECTOR_STRONG
682 stackp-flag := -fstack-protector-strong
683 stackp-name := STRONG
685 # Force off for distro compilers that enable stack protector by default.
686 stackp-flag := $(call cc-option, -fno-stack-protector)
689 # Find arch-specific stack protector compiler sanity-checking script.
690 ifdef CONFIG_CC_STACKPROTECTOR
691 stackp-path := $(srctree)/scripts/gcc-$(SRCARCH)_$(BITS)-has-stack-protector.sh
692 stackp-check := $(wildcard $(stackp-path))
694 KBUILD_CFLAGS += $(stackp-flag)
696 ifeq ($(cc-name),clang)
697 ifneq ($(CROSS_COMPILE),)
698 CLANG_TARGET := -target $(notdir $(CROSS_COMPILE:%-=%))
699 GCC_TOOLCHAIN := $(realpath $(dir $(shell which $(LD)))/..)
701 ifneq ($(GCC_TOOLCHAIN),)
702 CLANG_GCC_TC := -gcc-toolchain $(GCC_TOOLCHAIN)
704 KBUILD_CFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC)
705 KBUILD_AFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC)
706 KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
707 KBUILD_CFLAGS += $(call cc-disable-warning, unused-variable)
708 KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier)
709 KBUILD_CFLAGS += $(call cc-disable-warning, gnu)
710 # Quiet clang warning: comparison of unsigned expression < 0 is always false
711 KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare)
712 # CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
713 # source of a reference will be _MergedGlobals and not on of the whitelisted names.
714 # See modpost pattern 2
715 KBUILD_CFLAGS += $(call cc-option, -mno-global-merge,)
716 KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior)
717 KBUILD_CFLAGS += $(call cc-option, -no-integrated-as)
718 KBUILD_AFLAGS += $(call cc-option, -no-integrated-as)
721 # These warnings generated too much noise in a regular build.
722 # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
723 KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
724 KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
727 ifdef CONFIG_FRAME_POINTER
728 KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
730 # Some targets (ARM with Thumb2, for example), can't be built with frame
731 # pointers. For those, we don't have FUNCTION_TRACER automatically
732 # select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
733 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
734 # -fomit-frame-pointer with FUNCTION_TRACER.
735 ifndef CONFIG_FUNCTION_TRACER
736 KBUILD_CFLAGS += -fomit-frame-pointer
740 KBUILD_CFLAGS += $(call cc-option, -fno-var-tracking-assignments)
742 ifdef CONFIG_DEBUG_INFO
743 ifdef CONFIG_DEBUG_INFO_SPLIT
744 KBUILD_CFLAGS += $(call cc-option, -gsplit-dwarf, -g)
748 KBUILD_AFLAGS += -Wa,-gdwarf-2
750 ifdef CONFIG_DEBUG_INFO_DWARF4
751 KBUILD_CFLAGS += $(call cc-option, -gdwarf-4,)
754 ifdef CONFIG_DEBUG_INFO_REDUCED
755 KBUILD_CFLAGS += $(call cc-option, -femit-struct-debug-baseonly) \
756 $(call cc-option,-fno-var-tracking)
759 ifdef CONFIG_FUNCTION_TRACER
760 ifndef CC_FLAGS_FTRACE
761 CC_FLAGS_FTRACE := -pg
763 export CC_FLAGS_FTRACE
764 ifdef CONFIG_HAVE_FENTRY
765 CC_USING_FENTRY := $(call cc-option, -mfentry -DCC_USING_FENTRY)
767 KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_USING_FENTRY)
768 KBUILD_AFLAGS += $(CC_USING_FENTRY)
769 ifdef CONFIG_DYNAMIC_FTRACE
770 ifdef CONFIG_HAVE_C_RECORDMCOUNT
771 BUILD_C_RECORDMCOUNT := y
772 export BUILD_C_RECORDMCOUNT
777 # We trigger additional mismatches with less inlining
778 ifdef CONFIG_DEBUG_SECTION_MISMATCH
779 KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
782 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
783 KBUILD_CFLAGS += $(call cc-option,-ffunction-sections,)
784 KBUILD_CFLAGS += $(call cc-option,-fdata-sections,)
787 # arch Makefile may override CC so keep this after arch Makefile is included
788 NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
789 CHECKFLAGS += $(NOSTDINC_FLAGS)
791 # warn about C99 declaration after statement
792 KBUILD_CFLAGS += $(call cc-option,-Wdeclaration-after-statement,)
794 # disable pointer signed / unsigned warnings in gcc 4.0
795 KBUILD_CFLAGS += $(call cc-disable-warning, pointer-sign)
797 # disable invalid "can't wrap" optimizations for signed / pointers
798 KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow)
800 # conserve stack if available
801 KBUILD_CFLAGS += $(call cc-option,-fconserve-stack)
803 # disallow errors like 'EXPORT_GPL(foo);' with missing header
804 KBUILD_CFLAGS += $(call cc-option,-Werror=implicit-int)
806 # require functions to have arguments in prototypes, not empty 'int foo()'
807 KBUILD_CFLAGS += $(call cc-option,-Werror=strict-prototypes)
809 # Prohibit date/time macros, which would make the build non-deterministic
810 KBUILD_CFLAGS += $(call cc-option,-Werror=date-time)
812 # enforce correct pointer usage
813 KBUILD_CFLAGS += $(call cc-option,-Werror=incompatible-pointer-types)
815 # Require designated initializers for all marked structures
816 KBUILD_CFLAGS += $(call cc-option,-Werror=designated-init)
818 # use the deterministic mode of AR if available
819 KBUILD_ARFLAGS := $(call ar-option,D)
821 include scripts/Makefile.kasan
822 include scripts/Makefile.extrawarn
823 include scripts/Makefile.ubsan
825 # Add any arch overrides and user supplied CPPFLAGS, AFLAGS and CFLAGS as the
827 KBUILD_CPPFLAGS += $(ARCH_CPPFLAGS) $(KCPPFLAGS)
828 KBUILD_AFLAGS += $(ARCH_AFLAGS) $(KAFLAGS)
829 KBUILD_CFLAGS += $(ARCH_CFLAGS) $(KCFLAGS)
831 # Use --build-id when available.
832 LDFLAGS_BUILD_ID := $(patsubst -Wl$(comma)%,%,\
833 $(call cc-ldoption, -Wl$(comma)--build-id,))
834 KBUILD_LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID)
835 LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)
837 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
838 LDFLAGS_vmlinux += $(call ld-option, --gc-sections,)
841 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
842 LDFLAGS_vmlinux += $(call ld-option, -X,)
845 # Default kernel image to build when no specific target is given.
846 # KBUILD_IMAGE may be overruled on the command line or
847 # set in the environment
848 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
850 export KBUILD_IMAGE ?= vmlinux
853 # INSTALL_PATH specifies where to place the updated kernel and system map
854 # images. Default is /boot, but you can set it to other values
855 export INSTALL_PATH ?= /boot
858 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
859 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
860 # an argument if needed. Otherwise it defaults to the kernel install path
862 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
865 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
866 # relocations required by build roots. This is not defined in the
867 # makefile but the argument can be passed to make if needed.
870 MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
874 # INSTALL_MOD_STRIP, if defined, will cause modules to be
875 # stripped after they are installed. If INSTALL_MOD_STRIP is '1', then
876 # the default option --strip-debug will be used. Otherwise,
877 # INSTALL_MOD_STRIP value will be used as the options to the strip command.
879 ifdef INSTALL_MOD_STRIP
880 ifeq ($(INSTALL_MOD_STRIP),1)
881 mod_strip_cmd = $(STRIP) --strip-debug
883 mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
884 endif # INSTALL_MOD_STRIP=1
887 endif # INSTALL_MOD_STRIP
890 # CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
891 # after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
892 # or CONFIG_MODULE_COMPRESS_XZ.
894 mod_compress_cmd = true
895 ifdef CONFIG_MODULE_COMPRESS
896 ifdef CONFIG_MODULE_COMPRESS_GZIP
897 mod_compress_cmd = gzip -n -f
898 endif # CONFIG_MODULE_COMPRESS_GZIP
899 ifdef CONFIG_MODULE_COMPRESS_XZ
900 mod_compress_cmd = xz -f
901 endif # CONFIG_MODULE_COMPRESS_XZ
902 endif # CONFIG_MODULE_COMPRESS
903 export mod_compress_cmd
905 # Select initial ramdisk compression format, default is gzip(1).
906 # This shall be used by the dracut(8) tool while creating an initramfs image.
908 INITRD_COMPRESS-y := gzip
909 INITRD_COMPRESS-$(CONFIG_RD_BZIP2) := bzip2
910 INITRD_COMPRESS-$(CONFIG_RD_LZMA) := lzma
911 INITRD_COMPRESS-$(CONFIG_RD_XZ) := xz
912 INITRD_COMPRESS-$(CONFIG_RD_LZO) := lzo
913 INITRD_COMPRESS-$(CONFIG_RD_LZ4) := lz4
914 # do not export INITRD_COMPRESS, since we didn't actually
915 # choose a sane default compression above.
916 # export INITRD_COMPRESS := $(INITRD_COMPRESS-y)
918 ifdef CONFIG_MODULE_SIG_ALL
919 $(eval $(call config_filename,MODULE_SIG_KEY))
921 mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
927 ifdef CONFIG_STACK_VALIDATION
928 has_libelf := $(call try-run,\
929 echo "int main() {}" | $(HOSTCC) -xc -o /dev/null -lelf -,1,0)
930 ifeq ($(has_libelf),1)
931 objtool_target := tools/objtool FORCE
933 $(warning "Cannot use CONFIG_STACK_VALIDATION, please install libelf-dev, libelf-devel or elfutils-libelf-devel")
934 SKIP_STACK_VALIDATION := 1
935 export SKIP_STACK_VALIDATION
940 ifeq ($(KBUILD_EXTMOD),)
941 core-y += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
943 vmlinux-dirs := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
944 $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
945 $(net-y) $(net-m) $(libs-y) $(libs-m) $(virt-y)))
947 vmlinux-alldirs := $(sort $(vmlinux-dirs) $(patsubst %/,%,$(filter %/, \
948 $(init-) $(core-) $(drivers-) $(net-) $(libs-) $(virt-))))
950 init-y := $(patsubst %/, %/built-in.o, $(init-y))
951 core-y := $(patsubst %/, %/built-in.o, $(core-y))
952 drivers-y := $(patsubst %/, %/built-in.o, $(drivers-y))
953 net-y := $(patsubst %/, %/built-in.o, $(net-y))
954 libs-y1 := $(patsubst %/, %/lib.a, $(libs-y))
955 libs-y2 := $(patsubst %/, %/built-in.o, $(libs-y))
956 libs-y := $(libs-y1) $(libs-y2)
957 virt-y := $(patsubst %/, %/built-in.o, $(virt-y))
959 # Externally visible symbols (used by link-vmlinux.sh)
960 export KBUILD_VMLINUX_INIT := $(head-y) $(init-y)
961 export KBUILD_VMLINUX_MAIN := $(core-y) $(libs-y) $(drivers-y) $(net-y) $(virt-y)
962 export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
963 export LDFLAGS_vmlinux
964 # used by scripts/pacmage/Makefile
965 export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) arch Documentation include samples scripts tools)
967 vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_INIT) $(KBUILD_VMLINUX_MAIN)
969 # Include targets which we want to execute sequentially if the rest of the
970 # kernel build went well. If CONFIG_TRIM_UNUSED_KSYMS is set, this might be
971 # evaluated more than once.
972 PHONY += vmlinux_prereq
973 vmlinux_prereq: $(vmlinux-deps) FORCE
974 ifdef CONFIG_HEADERS_CHECK
975 $(Q)$(MAKE) -f $(srctree)/Makefile headers_check
977 ifdef CONFIG_GDB_SCRIPTS
978 $(Q)ln -fsn `cd $(srctree) && /bin/pwd`/scripts/gdb/vmlinux-gdb.py
980 ifdef CONFIG_TRIM_UNUSED_KSYMS
981 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
982 "$(MAKE) -f $(srctree)/Makefile vmlinux"
985 # standalone target for easier testing
986 include/generated/autoksyms.h: FORCE
987 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh true
989 ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
991 # Final link of vmlinux with optional arch pass after final link
993 $(CONFIG_SHELL) $< $(LD) $(LDFLAGS) $(LDFLAGS_vmlinux) ; \
994 $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
996 vmlinux: scripts/link-vmlinux.sh vmlinux_prereq $(vmlinux-deps) FORCE
997 +$(call if_changed,link-vmlinux)
999 # Build samples along the rest of the kernel
1000 ifdef CONFIG_SAMPLES
1001 vmlinux-dirs += samples
1004 # The actual objects are generated when descending,
1005 # make sure no implicit rule kicks in
1006 $(sort $(vmlinux-deps)): $(vmlinux-dirs) ;
1008 # Handle descending into subdirectories listed in $(vmlinux-dirs)
1009 # Preset locale variables to speed up the build process. Limit locale
1010 # tweaks to this spot to avoid wrong language settings when running
1011 # make menuconfig etc.
1012 # Error messages still appears in the original language
1014 PHONY += $(vmlinux-dirs)
1015 $(vmlinux-dirs): prepare scripts
1016 $(Q)$(MAKE) $(build)=$@
1018 define filechk_kernel.release
1019 echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1022 # Store (new) KERNELRELEASE string in include/config/kernel.release
1023 include/config/kernel.release: include/config/auto.conf FORCE
1024 $(call filechk,kernel.release)
1027 # Things we need to do before we recursively start building the kernel
1028 # or the modules are listed in "prepare".
1029 # A multi level approach is used. prepareN is processed before prepareN-1.
1030 # archprepare is used in arch Makefiles and when processed asm symlink,
1031 # version.h and scripts_basic is processed / created.
1033 # Listed in dependency order
1034 PHONY += prepare archprepare prepare0 prepare1 prepare2 prepare3
1036 # prepare3 is used to check if we are building in a separate output directory,
1038 # 1) Check that make has not been executed in the kernel src $(srctree)
1039 prepare3: include/config/kernel.release
1040 ifneq ($(KBUILD_SRC),)
1041 @$(kecho) ' Using $(srctree) as source for kernel'
1042 $(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \
1043 echo >&2 " $(srctree) is not clean, please run 'make mrproper'"; \
1044 echo >&2 " in the '$(srctree)' directory.";\
1049 # prepare2 creates a makefile if using a separate output directory.
1050 # From this point forward, .config has been reprocessed, so any rules
1051 # that need to depend on updated CONFIG_* values can be checked here.
1052 prepare2: prepare3 prepare-compiler-check outputmakefile asm-generic
1054 prepare1: prepare2 $(version_h) include/generated/utsrelease.h \
1055 include/config/auto.conf
1058 archprepare: archheaders archscripts prepare1 scripts_basic
1060 prepare0: archprepare gcc-plugins
1061 $(Q)$(MAKE) $(build)=.
1063 # All the preparing..
1064 prepare: prepare0 prepare-objtool
1066 PHONY += prepare-objtool
1067 prepare-objtool: $(objtool_target)
1069 # Check for CONFIG flags that require compiler support. Abort the build
1070 # after .config has been processed, but before the kernel build starts.
1072 # For security-sensitive CONFIG options, we don't want to fallback and/or
1073 # silently change which compiler flags will be used, since that leads to
1074 # producing kernels with different security feature characteristics
1075 # depending on the compiler used. (For example, "But I selected
1076 # CC_STACKPROTECTOR_STRONG! Why did it build with _REGULAR?!")
1077 PHONY += prepare-compiler-check
1078 prepare-compiler-check: FORCE
1079 # Make sure compiler supports requested stack protector flag.
1081 ifeq ($(call cc-option, $(stackp-flag)),)
1082 @echo Cannot use CONFIG_CC_STACKPROTECTOR_$(stackp-name): \
1083 $(stackp-flag) not supported by compiler >&2 && exit 1
1086 # Make sure compiler does not have buggy stack-protector support.
1088 ifneq ($(shell $(CONFIG_SHELL) $(stackp-check) $(CC) $(KBUILD_CPPFLAGS) $(biarch)),y)
1089 @echo Cannot use CONFIG_CC_STACKPROTECTOR_$(stackp-name): \
1090 $(stackp-flag) available but compiler is broken >&2 && exit 1
1095 # Generate some files
1096 # ---------------------------------------------------------------------------
1098 # KERNELRELEASE can change from a few different places, meaning version.h
1099 # needs to be updated, so this check is forced on all builds
1102 define filechk_utsrelease.h
1103 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1104 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1107 (echo \#define UTS_RELEASE \"$(KERNELRELEASE)\";)
1110 define filechk_version.h
1111 (echo \#define LINUX_VERSION_CODE $(shell \
1112 expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1113 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))';)
1116 $(version_h): $(srctree)/Makefile FORCE
1117 $(call filechk,version.h)
1118 $(Q)rm -f $(old_version_h)
1120 include/generated/utsrelease.h: include/config/kernel.release FORCE
1121 $(call filechk,utsrelease.h)
1125 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1126 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1128 # ---------------------------------------------------------------------------
1130 INSTALL_FW_PATH=$(INSTALL_MOD_PATH)/lib/firmware
1131 export INSTALL_FW_PATH
1133 PHONY += firmware_install
1135 @mkdir -p $(objtree)/firmware
1136 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_install
1138 # ---------------------------------------------------------------------------
1141 #Default location for installed headers
1142 export INSTALL_HDR_PATH = $(objtree)/usr
1144 # If we do an all arch process set dst to asm-$(hdr-arch)
1145 hdr-dst = $(if $(KBUILD_HEADERS), dst=include/arch-$(hdr-arch), dst=include)
1147 PHONY += archheaders
1150 PHONY += archscripts
1154 __headers: $(version_h) scripts_basic asm-generic archheaders archscripts
1155 $(Q)$(MAKE) $(build)=scripts build_unifdef
1157 PHONY += headers_install_all
1158 headers_install_all:
1159 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh install
1161 PHONY += headers_install
1162 headers_install: __headers
1163 $(if $(wildcard $(srctree)/arch/$(hdr-arch)/include/uapi/asm/Kbuild),, \
1164 $(error Headers not exportable for the $(SRCARCH) architecture))
1165 $(Q)$(MAKE) $(hdr-inst)=include/uapi
1166 $(Q)$(MAKE) $(hdr-inst)=arch/$(hdr-arch)/include/uapi $(hdr-dst)
1168 PHONY += headers_check_all
1169 headers_check_all: headers_install_all
1170 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh check
1172 PHONY += headers_check
1173 headers_check: headers_install
1174 $(Q)$(MAKE) $(hdr-inst)=include/uapi HDRCHECK=1
1175 $(Q)$(MAKE) $(hdr-inst)=arch/$(hdr-arch)/include/uapi $(hdr-dst) HDRCHECK=1
1177 # ---------------------------------------------------------------------------
1182 $(Q)$(MAKE) -C tools/testing/selftests run_tests
1185 $(Q)$(MAKE) -C tools/testing/selftests clean
1187 PHONY += kselftest-merge
1189 $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1190 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/kconfig/merge_config.sh \
1191 -m $(objtree)/.config \
1192 $(srctree)/tools/testing/selftests/*/config
1193 +$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1195 # ---------------------------------------------------------------------------
1198 ifdef CONFIG_MODULES
1200 # By default, build modules as well
1206 # A module can be listed more than once in obj-m resulting in
1207 # duplicate lines in modules.order files. Those are removed
1208 # using awk while concatenating to the final file.
1211 modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux) modules.builtin
1212 $(Q)$(AWK) '!x[$$0]++' $(vmlinux-dirs:%=$(objtree)/%/modules.order) > $(objtree)/modules.order
1213 @$(kecho) ' Building modules, stage 2.';
1214 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1215 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_modbuild
1217 modules.builtin: $(vmlinux-dirs:%=%/modules.builtin)
1218 $(Q)$(AWK) '!x[$$0]++' $^ > $(objtree)/modules.builtin
1220 %/modules.builtin: include/config/auto.conf
1221 $(Q)$(MAKE) $(modbuiltin)=$*
1224 # Target to prepare building external modules
1225 PHONY += modules_prepare
1226 modules_prepare: prepare scripts
1228 # Target to install modules
1229 PHONY += modules_install
1230 modules_install: _modinst_ _modinst_post
1234 @rm -rf $(MODLIB)/kernel
1235 @rm -f $(MODLIB)/source
1236 @mkdir -p $(MODLIB)/kernel
1237 @ln -s `cd $(srctree) && /bin/pwd` $(MODLIB)/source
1238 @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
1239 rm -f $(MODLIB)/build ; \
1240 ln -s $(CURDIR) $(MODLIB)/build ; \
1242 @cp -f $(objtree)/modules.order $(MODLIB)/
1243 @cp -f $(objtree)/modules.builtin $(MODLIB)/
1244 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1246 # This depmod is only for convenience to give the initial
1247 # boot a modules.dep even before / is mounted read-write. However the
1248 # boot script depmod is the master version.
1249 PHONY += _modinst_post
1250 _modinst_post: _modinst_
1251 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_modinst
1254 ifeq ($(CONFIG_MODULE_SIG), y)
1255 PHONY += modules_sign
1257 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1260 else # CONFIG_MODULES
1262 # Modules not configured
1263 # ---------------------------------------------------------------------------
1265 PHONY += modules modules_install
1266 modules modules_install:
1268 @echo >&2 "The present kernel configuration has modules disabled."
1269 @echo >&2 "Type 'make config' and enable loadable module support."
1270 @echo >&2 "Then build a kernel with module support enabled."
1274 endif # CONFIG_MODULES
1277 # Cleaning is done on three levels.
1278 # make clean Delete most generated files
1279 # Leave enough to build external modules
1280 # make mrproper Delete the current configuration, and all generated files
1281 # make distclean Remove editor backup files, patch leftover files and the like
1283 # Directories & files removed with 'make clean'
1284 CLEAN_DIRS += $(MODVERDIR)
1286 # Directories & files removed with 'make mrproper'
1287 MRPROPER_DIRS += include/config usr/include include/generated \
1288 arch/*/include/generated .tmp_objdiff
1289 MRPROPER_FILES += .config .config.old .version .old_version \
1290 Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS \
1291 signing_key.pem signing_key.priv signing_key.x509 \
1292 x509.genkey extra_certificates signing_key.x509.keyid \
1293 signing_key.x509.signer vmlinux-gdb.py
1295 # clean - Delete most, but leave enough to build external modules
1297 clean: rm-dirs := $(CLEAN_DIRS)
1298 clean: rm-files := $(CLEAN_FILES)
1299 clean-dirs := $(addprefix _clean_, . $(vmlinux-alldirs) Documentation samples)
1301 PHONY += $(clean-dirs) clean archclean vmlinuxclean
1303 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1306 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1307 $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1309 clean: archclean vmlinuxclean
1311 # mrproper - Delete all generated files, including .config
1313 mrproper: rm-dirs := $(wildcard $(MRPROPER_DIRS))
1314 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1315 mrproper-dirs := $(addprefix _mrproper_,Documentation/DocBook scripts)
1317 PHONY += $(mrproper-dirs) mrproper archmrproper
1319 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1321 mrproper: clean archmrproper $(mrproper-dirs)
1330 @find $(srctree) $(RCS_FIND_IGNORE) \
1331 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1332 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1333 -o -name 'core' \) \
1334 -type f -print | xargs rm -f
1337 # Packaging of the kernel to various formats
1338 # ---------------------------------------------------------------------------
1339 # rpm target kept for backward compatibility
1340 package-dir := scripts/package
1343 $(Q)$(MAKE) $(build)=$(package-dir) $@
1344 %pkg: include/config/kernel.release FORCE
1345 $(Q)$(MAKE) $(build)=$(package-dir) $@
1346 rpm: include/config/kernel.release FORCE
1347 $(Q)$(MAKE) $(build)=$(package-dir) $@
1350 # Brief documentation of the typical targets used
1351 # ---------------------------------------------------------------------------
1353 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1354 boards := $(sort $(notdir $(boards)))
1355 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1356 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1360 @echo 'Cleaning targets:'
1361 @echo ' clean - Remove most generated files but keep the config and'
1362 @echo ' enough build support to build external modules'
1363 @echo ' mrproper - Remove all generated files + config + various backup files'
1364 @echo ' distclean - mrproper + remove editor backup and patch files'
1366 @echo 'Configuration targets:'
1367 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1369 @echo 'Other generic targets:'
1370 @echo ' all - Build all targets marked with [*]'
1371 @echo '* vmlinux - Build the bare kernel'
1372 @echo '* modules - Build all modules'
1373 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1374 @echo ' firmware_install- Install all firmware to INSTALL_FW_PATH'
1375 @echo ' (default: $$(INSTALL_MOD_PATH)/lib/firmware)'
1376 @echo ' dir/ - Build all files in dir and below'
1377 @echo ' dir/file.[ois] - Build specified target only'
1378 @echo ' dir/file.ll - Build the LLVM assembly file'
1379 @echo ' (requires compiler support for LLVM assembly generation)'
1380 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1381 @echo ' (requires a recent binutils and recent build (System.map))'
1382 @echo ' dir/file.ko - Build module including final link'
1383 @echo ' modules_prepare - Set up for building external modules'
1384 @echo ' tags/TAGS - Generate tags file for editors'
1385 @echo ' cscope - Generate cscope index'
1386 @echo ' gtags - Generate GNU GLOBAL index'
1387 @echo ' kernelrelease - Output the release version string (use with make -s)'
1388 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1389 @echo ' image_name - Output the image name (use with make -s)'
1390 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1391 echo ' (default: $(INSTALL_HDR_PATH))'; \
1393 @echo 'Static analysers:'
1394 @echo ' checkstack - Generate a list of stack hogs'
1395 @echo ' namespacecheck - Name space analysis on compiled kernel'
1396 @echo ' versioncheck - Sanity check on version.h usage'
1397 @echo ' includecheck - Check for duplicate included header files'
1398 @echo ' export_report - List the usages of all exported symbols'
1399 @echo ' headers_check - Sanity check on exported headers'
1400 @echo ' headerdep - Detect inclusion cycles in headers'
1401 @$(MAKE) -f $(srctree)/scripts/Makefile.help checker-help
1403 @echo 'Kernel selftest:'
1404 @echo ' kselftest - Build and run kernel selftest (run as root)'
1405 @echo ' Build, install, and boot kernel before'
1406 @echo ' running kselftest on it'
1407 @echo ' kselftest-clean - Remove all generated kselftest files'
1408 @echo ' kselftest-merge - Merge all the config dependencies of kselftest to existed'
1411 @echo 'Userspace tools targets:'
1412 @echo ' use "make tools/help"'
1413 @echo ' or "cd tools; make help"'
1415 @echo 'Kernel packaging:'
1416 @$(MAKE) $(build)=$(package-dir) help
1418 @echo 'Documentation targets:'
1419 @$(MAKE) -f $(srctree)/Documentation/Makefile.sphinx dochelp
1421 @$(MAKE) -f $(srctree)/Documentation/DocBook/Makefile dochelp
1423 @echo 'Architecture specific targets ($(SRCARCH)):'
1424 @$(if $(archhelp),$(archhelp),\
1425 echo ' No architecture specific help defined for $(SRCARCH)')
1428 $(foreach b, $(boards), \
1429 printf " %-24s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1431 @$(if $(board-dirs), \
1432 $(foreach b, $(board-dirs), \
1433 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1434 printf " %-16s - Show all of the above\\n" help-boards; \
1437 @echo ' make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1438 @echo ' make V=2 [targets] 2 => give reason for rebuild of target'
1439 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1440 @echo ' make C=1 [targets] Check all c source with $$CHECK (sparse by default)'
1441 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1442 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1443 @echo ' make W=n [targets] Enable extra gcc checks, n=1,2,3 where'
1444 @echo ' 1: warnings which may be relevant and do not occur too often'
1445 @echo ' 2: warnings which occur quite often but may still be relevant'
1446 @echo ' 3: more obscure warnings, can most likely be ignored'
1447 @echo ' Multiple levels can be combined with W=12 or W=123'
1449 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1450 @echo 'For further info see the ./README file'
1453 help-board-dirs := $(addprefix help-,$(board-dirs))
1455 help-boards: $(help-board-dirs)
1457 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1459 $(help-board-dirs): help-%:
1460 @echo 'Architecture specific targets ($(SRCARCH) $*):'
1461 @$(if $(boards-per-dir), \
1462 $(foreach b, $(boards-per-dir), \
1463 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1467 # Documentation targets
1468 # ---------------------------------------------------------------------------
1469 DOC_TARGETS := xmldocs sgmldocs psdocs latexdocs pdfdocs htmldocs mandocs installmandocs epubdocs cleandocs linkcheckdocs
1470 PHONY += $(DOC_TARGETS)
1471 $(DOC_TARGETS): scripts_basic FORCE
1472 $(Q)$(MAKE) $(build)=scripts build_docproc build_check-lc_ctype
1473 $(Q)$(MAKE) $(build)=Documentation -f $(srctree)/Documentation/Makefile.sphinx $@
1474 $(Q)$(MAKE) $(build)=Documentation/DocBook $@
1476 else # KBUILD_EXTMOD
1479 # External module support.
1480 # When building external modules the kernel used as basis is considered
1481 # read-only, and no consistency checks are made and the make
1482 # system is not used on the basis kernel. If updates are required
1483 # in the basis kernel ordinary make commands (without M=...) must
1486 # The following are the only valid targets when building external
1488 # make M=dir clean Delete all automatically generated files
1489 # make M=dir modules Make all modules in specified dir
1490 # make M=dir Same as 'make M=dir modules'
1491 # make M=dir modules_install
1492 # Install the modules built in the module directory
1493 # Assumes install directory is already created
1495 # We are always building modules
1497 PHONY += crmodverdir
1501 PHONY += $(objtree)/Module.symvers
1502 $(objtree)/Module.symvers:
1503 @test -e $(objtree)/Module.symvers || ( \
1505 echo " WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1506 echo " is missing; modules will have no dependencies and modversions."; \
1509 module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
1510 PHONY += $(module-dirs) modules
1511 $(module-dirs): crmodverdir $(objtree)/Module.symvers
1512 $(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@)
1514 modules: $(module-dirs)
1515 @$(kecho) ' Building modules, stage 2.';
1516 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1518 PHONY += modules_install
1519 modules_install: _emodinst_ _emodinst_post
1521 install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1524 $(Q)mkdir -p $(MODLIB)/$(install-dir)
1525 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1527 PHONY += _emodinst_post
1528 _emodinst_post: _emodinst_
1531 clean-dirs := $(addprefix _clean_,$(KBUILD_EXTMOD))
1533 PHONY += $(clean-dirs) clean
1535 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1537 clean: rm-dirs := $(MODVERDIR)
1538 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers
1542 @echo ' Building external modules.'
1543 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1545 @echo ' modules - default target, build the module(s)'
1546 @echo ' modules_install - install the module'
1547 @echo ' clean - remove generated files in module directory only'
1551 PHONY += prepare scripts
1554 endif # KBUILD_EXTMOD
1556 clean: $(clean-dirs)
1559 @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1560 \( -name '*.[oas]' -o -name '*.ko' -o -name '.*.cmd' \
1564 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1565 -o -name '*.symtypes' -o -name 'modules.order' \
1566 -o -name modules.builtin -o -name '.tmp_*.o.*' \
1567 -o -name '*.c.[012]*.*' \
1569 -o -name '*.gcno' \) -type f -print | xargs rm -f
1571 # Generate tags for editors
1572 # ---------------------------------------------------------------------------
1573 quiet_cmd_tags = GEN $@
1574 cmd_tags = $(CONFIG_SHELL) $(srctree)/scripts/tags.sh $@
1576 tags TAGS cscope gtags: FORCE
1579 # Scripts to check various things for consistency
1580 # ---------------------------------------------------------------------------
1582 PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1585 find $(srctree)/* $(RCS_FIND_IGNORE) \
1586 -name '*.[hcS]' -type f -print | sort \
1587 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1590 find $(srctree)/* $(RCS_FIND_IGNORE) \
1591 -name '*.[hcS]' -type f -print | sort \
1592 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1595 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/$@
1598 $(PERL) $(srctree)/scripts/namespace.pl
1601 $(PERL) $(srctree)/scripts/export_report.pl
1603 endif #ifeq ($(config-targets),1)
1604 endif #ifeq ($(mixed-targets),1)
1606 PHONY += checkstack kernelrelease kernelversion image_name
1608 # UML needs a little special treatment here. It wants to use the host
1609 # toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
1610 # else wants $(ARCH), including people doing cross-builds, which means
1611 # that $(SUBARCH) doesn't work here.
1613 CHECKSTACK_ARCH := $(SUBARCH)
1615 CHECKSTACK_ARCH := $(ARCH)
1618 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1619 $(PERL) $(src)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1622 @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1625 @echo $(KERNELVERSION)
1628 @echo $(KBUILD_IMAGE)
1630 # Clear a bunch of variables before executing the submake
1632 $(Q)mkdir -p $(objtree)/tools
1633 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(shell cd $(objtree) && /bin/pwd) subdir=tools -C $(src)/tools/
1636 $(Q)mkdir -p $(objtree)/tools
1637 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(shell cd $(objtree) && /bin/pwd) subdir=tools -C $(src)/tools/ $*
1640 # ---------------------------------------------------------------------------
1641 # Single targets are compatible with:
1642 # - build with mixed source and output
1643 # - build with separate output dir 'make O=...'
1644 # - external modules
1646 # target-dir => where to store outputfile
1647 # build-dir => directory in kernel source tree to use
1649 ifeq ($(KBUILD_EXTMOD),)
1650 build-dir = $(patsubst %/,%,$(dir $@))
1651 target-dir = $(dir $@)
1653 zap-slash=$(filter-out .,$(patsubst %/,%,$(dir $@)))
1654 build-dir = $(KBUILD_EXTMOD)$(if $(zap-slash),/$(zap-slash))
1655 target-dir = $(if $(KBUILD_EXTMOD),$(dir $<),$(dir $@))
1658 %.s: %.c prepare scripts FORCE
1659 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1660 %.i: %.c prepare scripts FORCE
1661 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1662 %.o: %.c prepare scripts FORCE
1663 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1664 %.lst: %.c prepare scripts FORCE
1665 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1666 %.s: %.S prepare scripts FORCE
1667 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1668 %.o: %.S prepare scripts FORCE
1669 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1670 %.symtypes: %.c prepare scripts FORCE
1671 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1672 %.ll: %.c prepare scripts FORCE
1673 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1676 /: prepare scripts FORCE
1678 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1679 $(build)=$(build-dir)
1680 # Make sure the latest headers are built for Documentation
1681 Documentation/ samples/: headers_install
1682 %/: prepare scripts FORCE
1684 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1685 $(build)=$(build-dir)
1686 %.ko: prepare scripts FORCE
1688 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1689 $(build)=$(build-dir) $(@:.ko=.o)
1690 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1692 # FIXME Should go into a make.lib or something
1693 # ===========================================================================
1695 quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN $(wildcard $(rm-dirs)))
1696 cmd_rmdirs = rm -rf $(rm-dirs)
1698 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
1699 cmd_rmfiles = rm -f $(rm-files)
1701 # Run depmod only if we have System.map and depmod is executable
1702 quiet_cmd_depmod = DEPMOD $(KERNELRELEASE)
1703 cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1704 $(KERNELRELEASE) "$(patsubst y,_,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX))"
1706 # Create temporary dir for module support files
1707 # clean it up only when building all modules
1708 cmd_crmodverdir = $(Q)mkdir -p $(MODVERDIR) \
1709 $(if $(KBUILD_MODULES),; rm -f $(MODVERDIR)/*)
1711 # read all saved command lines
1713 targets := $(wildcard $(sort $(targets)))
1714 cmd_files := $(wildcard .*.cmd $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
1716 ifneq ($(cmd_files),)
1717 $(cmd_files): ; # Do not try to update included dependency files
1718 include $(cmd_files)
1721 endif # skip-makefile
1726 # Declare the contents of the .PHONY variable as phony. We keep that
1727 # information in a variable so we can use it in if_changed and friends.