1 # SPDX-License-Identifier: GPL-2.0
9 # To see a list of typical targets execute "make help"
10 # More info can be located in ./README
11 # Comments in this file are targeted only to the developer, do not
12 # expect to learn how to build the kernel reading this file.
14 # That's our default target when none is given on the command line
18 # Do not use make's built-in rules and variables
19 # (this increases performance and avoids hard-to-debug behaviour)
22 # Avoid funny character set dependencies
26 export LC_COLLATE LC_NUMERIC
28 # Avoid interference with shell env settings
31 # We are using a recursive build, so we need to do a little thinking
32 # to get the ordering right.
34 # Most importantly: sub-Makefiles should only ever modify files in
35 # their own directory. If in some directory we have a dependency on
36 # a file in another dir (which doesn't happen often, but it's often
37 # unavoidable when linking the built-in.a targets which finally
38 # turn into vmlinux), we will call a sub make in that other dir, and
39 # after that we are sure that everything which is in that other dir
42 # The only cases where we need to modify files which have global
43 # effects are thus separated out and done before the recursive
44 # descending is started. They are now explicitly listed as the
48 # ---------------------------------------------------------------------------
50 # Normally, we echo the whole command before executing it. By making
51 # that echo $($(quiet)$(cmd)), we now have the possibility to set
52 # $(quiet) to choose other forms of output instead, e.g.
54 # quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
55 # cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
57 # If $(quiet) is empty, the whole command will be printed.
58 # If it is set to "quiet_", only the short version will be printed.
59 # If it is set to "silent_", nothing will be printed at all, since
60 # the variable $(silent_cmd_cc_o_c) doesn't exist.
62 # A simple variant is to prefix commands with $(Q) - that's useful
63 # for commands that shall be hidden in non-verbose mode.
67 # If KBUILD_VERBOSE equals 0 then the above command will be hidden.
68 # If KBUILD_VERBOSE equals 1 then the above command is displayed.
70 # To put more focus on warnings, be less verbose as default
71 # Use 'make V=1' to see the full commands
73 ifeq ("$(origin V)", "command line")
80 ifeq ($(KBUILD_VERBOSE),1)
88 # If the user is running make -s (silent mode), suppress echoing of
91 ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
96 export quiet Q KBUILD_VERBOSE
98 # kbuild supports saving output files in a separate directory.
99 # To locate output files in a separate directory two syntaxes are supported.
100 # In both cases the working directory must be the root of the kernel src.
102 # Use "make O=dir/to/store/output/files/"
104 # 2) Set KBUILD_OUTPUT
105 # Set the environment variable KBUILD_OUTPUT to point to the directory
106 # where the output files shall be placed.
107 # export KBUILD_OUTPUT=dir/to/store/output/files/
110 # The O= assignment takes precedence over the KBUILD_OUTPUT environment
113 # KBUILD_SRC is not intended to be used by the regular user (for now),
114 # it is set on invocation of make with KBUILD_OUTPUT or O= specified.
115 ifeq ($(KBUILD_SRC),)
117 # OK, Make called in directory where kernel src resides
118 # Do we want to locate output files in a separate directory?
119 ifeq ("$(origin O)", "command line")
120 KBUILD_OUTPUT := $(O)
123 # Cancel implicit rules on top Makefile
124 $(CURDIR)/Makefile Makefile: ;
126 ifneq ($(words $(subst :, ,$(CURDIR))), 1)
127 $(error main directory cannot contain spaces nor colons)
130 ifneq ($(KBUILD_OUTPUT),)
131 # check that the output directory actually exists
132 saved-output := $(KBUILD_OUTPUT)
133 KBUILD_OUTPUT := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) \
135 $(if $(KBUILD_OUTPUT),, \
136 $(error failed to create output directory "$(saved-output)"))
138 # Look for make include files relative to root of kernel src
140 # This does not become effective immediately because MAKEFLAGS is re-parsed
141 # once after the Makefile is read. It is OK since we are going to invoke
143 MAKEFLAGS += --include-dir=$(CURDIR)
145 PHONY += $(MAKECMDGOALS) sub-make
147 $(filter-out _all sub-make $(CURDIR)/Makefile, $(MAKECMDGOALS)) _all: sub-make
150 # Invoke a second make in the output directory, passing relevant variables
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 := $(M)
196 ifeq ($(KBUILD_SRC),)
197 # building in the source tree
200 ifeq ($(KBUILD_SRC)/,$(dir $(CURDIR)))
201 # building in a subdirectory of the source tree
204 srctree := $(KBUILD_SRC)
208 export KBUILD_CHECKSRC KBUILD_EXTMOD KBUILD_SRC
214 VPATH := $(srctree)$(if $(KBUILD_EXTMOD),:$(KBUILD_EXTMOD))
216 export srctree objtree VPATH
218 # To make sure we do not include .config for any of the *config targets
219 # catch them early, and hand them over to scripts/kconfig/Makefile
220 # It is allowed to specify more targets when calling make, including
221 # mixing *config targets and build targets.
222 # For example 'make oldconfig all'.
223 # Detect when mixed targets is specified, and make a second invocation
224 # of make so .config is not included in this case either (for *config).
226 version_h := include/generated/uapi/linux/version.h
227 old_version_h := include/linux/version.h
229 clean-targets := %clean mrproper cleandocs
230 no-dot-config-targets := $(clean-targets) \
231 cscope gtags TAGS tags help% %docs check% coccicheck \
232 $(version_h) headers_% archheaders archscripts \
233 %asm-generic kernelversion %src-pkg
234 no-sync-config-targets := $(no-dot-config-targets) install %install \
242 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
243 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
248 ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
249 ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
254 ifneq ($(KBUILD_EXTMOD),)
258 ifeq ($(KBUILD_EXTMOD),)
259 ifneq ($(filter config %config,$(MAKECMDGOALS)),)
261 ifneq ($(words $(MAKECMDGOALS)),1)
267 # For "make -j clean all", "make -j mrproper defconfig all", etc.
268 ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
269 ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
274 # install and modules_install need also be processed one by one
275 ifneq ($(filter install,$(MAKECMDGOALS)),)
276 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
281 ifeq ($(mixed-targets),1)
282 # ===========================================================================
283 # We're called with mixed targets (*config and build targets).
284 # Handle them one by one.
286 PHONY += $(MAKECMDGOALS) __build_one_by_one
288 $(filter-out __build_one_by_one, $(MAKECMDGOALS)): __build_one_by_one
293 for i in $(MAKECMDGOALS); do \
294 $(MAKE) -f $(srctree)/Makefile $$i; \
299 # We need some generic definitions (do not try to remake the file).
300 scripts/Kbuild.include: ;
301 include scripts/Kbuild.include
303 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
304 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
305 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
306 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
308 # SUBARCH tells the usermode build what the underlying arch is. That is set
309 # first, and if a usermode build is happening, the "ARCH=um" on the command
310 # line overrides the setting of ARCH below. If a native build is happening,
311 # then ARCH is assigned, getting whatever value it gets normally, and
312 # SUBARCH is subsequently ignored.
314 SUBARCH := $(shell uname -m | sed -e s/i.86/x86/ -e s/x86_64/x86/ \
315 -e s/sun4u/sparc64/ \
316 -e s/arm.*/arm/ -e s/sa110/arm/ \
317 -e s/s390x/s390/ -e s/parisc64/parisc/ \
318 -e s/ppc.*/powerpc/ -e s/mips.*/mips/ \
319 -e s/sh[234].*/sh/ -e s/aarch64.*/arm64/ \
322 # Cross compiling and selecting different set of gcc/bin-utils
323 # ---------------------------------------------------------------------------
325 # When performing cross compilation for other architectures ARCH shall be set
326 # to the target architecture. (See arch/* for the possibilities).
327 # ARCH can be set during invocation of make:
329 # Another way is to have ARCH set in the environment.
330 # The default ARCH is the host where make is executed.
332 # CROSS_COMPILE specify the prefix used for all executables used
333 # during compilation. Only gcc and related bin-utils executables
334 # are prefixed with $(CROSS_COMPILE).
335 # CROSS_COMPILE can be set on the command line
336 # make CROSS_COMPILE=ia64-linux-
337 # Alternatively CROSS_COMPILE can be set in the environment.
338 # Default value for CROSS_COMPILE is not to prefix executables
339 # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
342 # Architecture as present in compile.h
343 UTS_MACHINE := $(ARCH)
346 # Additional ARCH settings for x86
350 ifeq ($(ARCH),x86_64)
354 # Additional ARCH settings for sparc
355 ifeq ($(ARCH),sparc32)
358 ifeq ($(ARCH),sparc64)
362 # Additional ARCH settings for sh
367 KCONFIG_CONFIG ?= .config
368 export KCONFIG_CONFIG
370 # SHELL used by kbuild
371 CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
372 else if [ -x /bin/bash ]; then echo /bin/bash; \
373 else echo sh; fi ; fi)
375 HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
376 HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
377 HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
381 KBUILD_HOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 \
382 -fomit-frame-pointer -std=gnu89 $(HOST_LFS_CFLAGS) \
384 KBUILD_HOSTCXXFLAGS := -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
385 KBUILD_HOSTLDFLAGS := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
386 KBUILD_HOSTLDLIBS := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
388 # Make variables (CC, etc...)
389 AS = $(CROSS_COMPILE)as
390 LD = $(CROSS_COMPILE)ld
391 CC = $(CROSS_COMPILE)gcc
393 AR = $(CROSS_COMPILE)ar
394 NM = $(CROSS_COMPILE)nm
395 STRIP = $(CROSS_COMPILE)strip
396 OBJCOPY = $(CROSS_COMPILE)objcopy
397 OBJDUMP = $(CROSS_COMPILE)objdump
401 GENKSYMS = scripts/genksyms/genksyms
402 INSTALLKERNEL := installkernel
403 DEPMOD = /sbin/depmod
410 CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
411 -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
420 # Use USERINCLUDE when you must reference the UAPI directories only.
422 -I$(srctree)/arch/$(SRCARCH)/include/uapi \
423 -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
424 -I$(srctree)/include/uapi \
425 -I$(objtree)/include/generated/uapi \
426 -include $(srctree)/include/linux/kconfig.h
428 # Use LINUXINCLUDE when you must reference the include/ directory.
429 # Needed to be compatible with the O= option
431 -I$(srctree)/arch/$(SRCARCH)/include \
432 -I$(objtree)/arch/$(SRCARCH)/include/generated \
433 $(if $(KBUILD_SRC), -I$(srctree)/include) \
434 -I$(objtree)/include \
437 KBUILD_AFLAGS := -D__ASSEMBLY__
438 KBUILD_CFLAGS := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
439 -fno-strict-aliasing -fno-common -fshort-wchar \
440 -Werror-implicit-function-declaration \
441 -Wno-format-security \
443 KBUILD_CPPFLAGS := -D__KERNEL__
444 KBUILD_AFLAGS_KERNEL :=
445 KBUILD_CFLAGS_KERNEL :=
446 KBUILD_AFLAGS_MODULE := -DMODULE
447 KBUILD_CFLAGS_MODULE := -DMODULE
448 KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
450 GCC_PLUGINS_CFLAGS :=
452 export ARCH SRCARCH CONFIG_SHELL HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE AS LD CC
453 export CPP AR NM STRIP OBJCOPY OBJDUMP KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS
454 export MAKE LEX YACC AWK GENKSYMS INSTALLKERNEL PERL PYTHON PYTHON2 PYTHON3 UTS_MACHINE
455 export HOSTCXX KBUILD_HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
457 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
458 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
459 export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN
460 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
461 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
462 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
463 export KBUILD_ARFLAGS
465 # When compiling out-of-tree modules, put MODVERDIR in the module
466 # tree rather than in the kernel tree. The kernel tree might
468 export MODVERDIR := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_versions
470 # Files to ignore in find ... statements
472 export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o \
473 -name CVS -o -name .pc -o -name .hg -o -name .git \) \
475 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
476 --exclude CVS --exclude .pc --exclude .hg --exclude .git
478 # ===========================================================================
479 # Rules shared between *config targets and build targets
481 # Basic helpers built in scripts/basic/
482 PHONY += scripts_basic
484 $(Q)$(MAKE) $(build)=scripts/basic
485 $(Q)rm -f .tmp_quiet_recordmcount
487 # To avoid any implicit rule to kick in, define an empty command.
488 scripts/basic/%: scripts_basic ;
490 PHONY += outputmakefile
491 # outputmakefile generates a Makefile in the output directory, if using a
492 # separate output directory. This allows convenient use of make in the
495 ifneq ($(KBUILD_SRC),)
496 $(Q)ln -fsn $(srctree) source
497 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile \
498 $(srctree) $(objtree) $(VERSION) $(PATCHLEVEL)
501 ifeq ($(cc-name),clang)
502 ifneq ($(CROSS_COMPILE),)
503 CLANG_TARGET := --target=$(notdir $(CROSS_COMPILE:%-=%))
504 GCC_TOOLCHAIN := $(realpath $(dir $(shell which $(LD)))/..)
506 ifneq ($(GCC_TOOLCHAIN),)
507 CLANG_GCC_TC := --gcc-toolchain=$(GCC_TOOLCHAIN)
509 KBUILD_CFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC)
510 KBUILD_AFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC)
511 KBUILD_CFLAGS += $(call cc-option, -no-integrated-as)
512 KBUILD_AFLAGS += $(call cc-option, -no-integrated-as)
515 RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
516 RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
517 RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
518 RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
519 RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
520 RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
521 export RETPOLINE_CFLAGS
522 export RETPOLINE_VDSO_CFLAGS
524 KBUILD_CFLAGS += $(call cc-option,-fno-PIE)
525 KBUILD_AFLAGS += $(call cc-option,-fno-PIE)
527 # check for 'asm goto'
528 ifeq ($(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC) $(KBUILD_CFLAGS)), y)
529 CC_HAVE_ASM_GOTO := 1
530 KBUILD_CFLAGS += -DCC_HAVE_ASM_GOTO
531 KBUILD_AFLAGS += -DCC_HAVE_ASM_GOTO
534 # The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
535 # Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
536 # CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
537 # and from include/config/auto.conf.cmd to detect the compiler upgrade.
538 CC_VERSION_TEXT = $(shell $(CC) --version | head -n 1)
540 ifeq ($(config-targets),1)
541 # ===========================================================================
542 # *config targets only - make sure prerequisites are updated, and descend
543 # in scripts/kconfig to make the *config target
545 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
546 # KBUILD_DEFCONFIG may point out an alternative default configuration
547 # used for 'make defconfig'
548 include arch/$(SRCARCH)/Makefile
549 export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
551 config: scripts_basic outputmakefile FORCE
552 $(Q)$(MAKE) $(build)=scripts/kconfig $@
554 %config: scripts_basic outputmakefile FORCE
555 $(Q)$(MAKE) $(build)=scripts/kconfig $@
558 # ===========================================================================
559 # Build targets only - this includes vmlinux, arch specific targets, clean
560 # targets and others. In general all targets except *config targets.
562 # If building an external module we do not care about the all: rule
563 # but instead _all depend on modules
565 ifeq ($(KBUILD_EXTMOD),)
571 # Decide whether to build built-in, modular, or both.
572 # Normally, just do built-in.
577 # If we have only "make modules", don't compile built-in objects.
578 # When we're building modules with modversions, we need to consider
579 # the built-in objects during the descend as well, in order to
580 # make sure the checksums are up to date before we record them.
582 ifeq ($(MAKECMDGOALS),modules)
583 KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
586 # If we have "make <whatever> modules", compile modules
587 # in addition to whatever we do anyway.
588 # Just "make" or "make all" shall build modules as well
590 ifneq ($(filter all _all modules,$(MAKECMDGOALS)),)
594 ifeq ($(MAKECMDGOALS),)
598 export KBUILD_MODULES KBUILD_BUILTIN
600 ifeq ($(KBUILD_EXTMOD),)
601 # Objects we will link into vmlinux / subdirs we need to visit
603 drivers-y := drivers/ sound/ firmware/
608 endif # KBUILD_EXTMOD
610 ifeq ($(dot-config),1)
611 include include/config/auto.conf
614 # The all: target is the default when no target is given on the
616 # This allow a user to issue only 'make' to build a kernel including modules
617 # Defaults to vmlinux, but the arch makefile usually adds further targets
620 CFLAGS_GCOV := -fprofile-arcs -ftest-coverage \
621 $(call cc-option,-fno-tree-loop-im) \
622 $(call cc-disable-warning,maybe-uninitialized,)
625 # The arch Makefile can set ARCH_{CPP,A,C}FLAGS to override the default
626 # values of the respective KBUILD_* variables
630 include arch/$(SRCARCH)/Makefile
632 ifeq ($(dot-config),1)
633 ifeq ($(may-sync-config),1)
634 # Read in dependencies to all Kconfig* files, make sure to run syncconfig if
635 # changes are detected. This should be included after arch/$(SRCARCH)/Makefile
636 # because some architectures define CROSS_COMPILE there.
637 -include include/config/auto.conf.cmd
639 # To avoid any implicit rule to kick in, define an empty command
640 $(KCONFIG_CONFIG) include/config/auto.conf.cmd: ;
642 # The actual configuration files used during the build are stored in
643 # include/generated/ and include/config/. Update them if .config is newer than
644 # include/config/auto.conf (which mirrors .config).
645 include/config/%.conf: $(KCONFIG_CONFIG) include/config/auto.conf.cmd
646 $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
648 # External modules and some install targets need include/generated/autoconf.h
649 # and include/config/auto.conf but do not care if they are up-to-date.
650 # Use auto.conf to trigger the test
651 PHONY += include/config/auto.conf
653 include/config/auto.conf:
654 $(Q)test -e include/generated/autoconf.h -a -e $@ || ( \
656 echo >&2 " ERROR: Kernel configuration is invalid."; \
657 echo >&2 " include/generated/autoconf.h or $@ are missing.";\
658 echo >&2 " Run 'make oldconfig && make prepare' on kernel src to fix it."; \
662 endif # may-sync-config
663 endif # $(dot-config)
665 KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,)
666 KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,)
667 KBUILD_CFLAGS += $(call cc-disable-warning, format-truncation)
668 KBUILD_CFLAGS += $(call cc-disable-warning, format-overflow)
669 KBUILD_CFLAGS += $(call cc-disable-warning, int-in-bool-context)
671 ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
672 KBUILD_CFLAGS += $(call cc-option,-Oz,-Os)
673 KBUILD_CFLAGS += $(call cc-disable-warning,maybe-uninitialized,)
675 ifdef CONFIG_PROFILE_ALL_BRANCHES
676 KBUILD_CFLAGS += -O2 $(call cc-disable-warning,maybe-uninitialized,)
682 KBUILD_CFLAGS += $(call cc-ifversion, -lt, 0409, \
683 $(call cc-disable-warning,maybe-uninitialized,))
685 # Tell gcc to never replace conditional load with a non-conditional one
686 KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
688 include scripts/Makefile.kcov
689 include scripts/Makefile.gcc-plugins
691 ifdef CONFIG_READABLE_ASM
692 # Disable optimizations that make assembler listings hard to read.
693 # reorder blocks reorders the control in the function
694 # ipa clone creates specialized cloned functions
695 # partial inlining inlines only parts of functions
696 KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
697 $(call cc-option,-fno-ipa-cp-clone,) \
698 $(call cc-option,-fno-partial-inlining)
701 ifneq ($(CONFIG_FRAME_WARN),0)
702 KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
705 stackp-flags-$(CONFIG_CC_HAS_STACKPROTECTOR_NONE) := -fno-stack-protector
706 stackp-flags-$(CONFIG_STACKPROTECTOR) := -fstack-protector
707 stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG) := -fstack-protector-strong
709 KBUILD_CFLAGS += $(stackp-flags-y)
711 ifeq ($(cc-name),clang)
712 KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
713 KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier)
714 KBUILD_CFLAGS += $(call cc-disable-warning, gnu)
715 KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
716 # Quiet clang warning: comparison of unsigned expression < 0 is always false
717 KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare)
718 # CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
719 # source of a reference will be _MergedGlobals and not on of the whitelisted names.
720 # See modpost pattern 2
721 KBUILD_CFLAGS += $(call cc-option, -mno-global-merge,)
722 KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior)
725 # These warnings generated too much noise in a regular build.
726 # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
727 KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
730 KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
731 ifdef CONFIG_FRAME_POINTER
732 KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
734 # Some targets (ARM with Thumb2, for example), can't be built with frame
735 # pointers. For those, we don't have FUNCTION_TRACER automatically
736 # select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
737 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
738 # -fomit-frame-pointer with FUNCTION_TRACER.
739 ifndef CONFIG_FUNCTION_TRACER
740 KBUILD_CFLAGS += -fomit-frame-pointer
744 KBUILD_CFLAGS += $(call cc-option, -fno-var-tracking-assignments)
746 ifdef CONFIG_DEBUG_INFO
747 ifdef CONFIG_DEBUG_INFO_SPLIT
748 KBUILD_CFLAGS += $(call cc-option, -gsplit-dwarf, -g)
752 KBUILD_AFLAGS += -Wa,-gdwarf-2
754 ifdef CONFIG_DEBUG_INFO_DWARF4
755 KBUILD_CFLAGS += $(call cc-option, -gdwarf-4,)
758 ifdef CONFIG_DEBUG_INFO_REDUCED
759 KBUILD_CFLAGS += $(call cc-option, -femit-struct-debug-baseonly) \
760 $(call cc-option,-fno-var-tracking)
763 ifdef CONFIG_FUNCTION_TRACER
764 ifndef CC_FLAGS_FTRACE
765 CC_FLAGS_FTRACE := -pg
767 ifdef CONFIG_FTRACE_MCOUNT_RECORD
768 # gcc 5 supports generating the mcount tables directly
769 ifeq ($(call cc-option-yn,-mrecord-mcount),y)
770 CC_FLAGS_FTRACE += -mrecord-mcount
771 export CC_USING_RECORD_MCOUNT := 1
773 ifdef CONFIG_HAVE_NOP_MCOUNT
774 ifeq ($(call cc-option-yn, -mnop-mcount),y)
775 CC_FLAGS_FTRACE += -mnop-mcount
776 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
780 ifdef CONFIG_HAVE_FENTRY
781 ifeq ($(call cc-option-yn, -mfentry),y)
782 CC_FLAGS_FTRACE += -mfentry
783 CC_FLAGS_USING += -DCC_USING_FENTRY
786 export CC_FLAGS_FTRACE
787 KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
788 KBUILD_AFLAGS += $(CC_FLAGS_USING)
789 ifdef CONFIG_DYNAMIC_FTRACE
790 ifdef CONFIG_HAVE_C_RECORDMCOUNT
791 BUILD_C_RECORDMCOUNT := y
792 export BUILD_C_RECORDMCOUNT
797 # We trigger additional mismatches with less inlining
798 ifdef CONFIG_DEBUG_SECTION_MISMATCH
799 KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
802 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
803 KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
804 LDFLAGS_vmlinux += --gc-sections
807 # arch Makefile may override CC so keep this after arch Makefile is included
808 NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
810 # warn about C99 declaration after statement
811 KBUILD_CFLAGS += $(call cc-option,-Wdeclaration-after-statement,)
813 # disable pointer signed / unsigned warnings in gcc 4.0
814 KBUILD_CFLAGS += $(call cc-disable-warning, pointer-sign)
816 # disable stringop warnings in gcc 8+
817 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
819 # disable invalid "can't wrap" optimizations for signed / pointers
820 KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow)
822 # clang sets -fmerge-all-constants by default as optimization, but this
823 # is non-conforming behavior for C and in fact breaks the kernel, so we
824 # need to disable it here generally.
825 KBUILD_CFLAGS += $(call cc-option,-fno-merge-all-constants)
827 # for gcc -fno-merge-all-constants disables everything, but it is fine
828 # to have actual conforming behavior enabled.
829 KBUILD_CFLAGS += $(call cc-option,-fmerge-constants)
831 # Make sure -fstack-check isn't enabled (like gentoo apparently did)
832 KBUILD_CFLAGS += $(call cc-option,-fno-stack-check,)
834 # conserve stack if available
835 KBUILD_CFLAGS += $(call cc-option,-fconserve-stack)
837 # disallow errors like 'EXPORT_GPL(foo);' with missing header
838 KBUILD_CFLAGS += $(call cc-option,-Werror=implicit-int)
840 # require functions to have arguments in prototypes, not empty 'int foo()'
841 KBUILD_CFLAGS += $(call cc-option,-Werror=strict-prototypes)
843 # Prohibit date/time macros, which would make the build non-deterministic
844 KBUILD_CFLAGS += $(call cc-option,-Werror=date-time)
846 # enforce correct pointer usage
847 KBUILD_CFLAGS += $(call cc-option,-Werror=incompatible-pointer-types)
849 # Require designated initializers for all marked structures
850 KBUILD_CFLAGS += $(call cc-option,-Werror=designated-init)
852 # change __FILE__ to the relative path from the srctree
853 KBUILD_CFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
855 # use the deterministic mode of AR if available
856 KBUILD_ARFLAGS := $(call ar-option,D)
858 include scripts/Makefile.kasan
859 include scripts/Makefile.extrawarn
860 include scripts/Makefile.ubsan
862 # Add any arch overrides and user supplied CPPFLAGS, AFLAGS and CFLAGS as the
864 KBUILD_CPPFLAGS += $(ARCH_CPPFLAGS) $(KCPPFLAGS)
865 KBUILD_AFLAGS += $(ARCH_AFLAGS) $(KAFLAGS)
866 KBUILD_CFLAGS += $(ARCH_CFLAGS) $(KCFLAGS)
868 # Use --build-id when available.
869 LDFLAGS_BUILD_ID := $(call ld-option, --build-id)
870 KBUILD_LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID)
871 LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)
873 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
874 LDFLAGS_vmlinux += $(call ld-option, -X,)
877 # insure the checker run with the right endianness
878 CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
880 # the checker needs the correct machine size
881 CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
883 # Default kernel image to build when no specific target is given.
884 # KBUILD_IMAGE may be overruled on the command line or
885 # set in the environment
886 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
888 export KBUILD_IMAGE ?= vmlinux
891 # INSTALL_PATH specifies where to place the updated kernel and system map
892 # images. Default is /boot, but you can set it to other values
893 export INSTALL_PATH ?= /boot
896 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
897 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
898 # an argument if needed. Otherwise it defaults to the kernel install path
900 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
903 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
904 # relocations required by build roots. This is not defined in the
905 # makefile but the argument can be passed to make if needed.
908 MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
912 # INSTALL_MOD_STRIP, if defined, will cause modules to be
913 # stripped after they are installed. If INSTALL_MOD_STRIP is '1', then
914 # the default option --strip-debug will be used. Otherwise,
915 # INSTALL_MOD_STRIP value will be used as the options to the strip command.
917 ifdef INSTALL_MOD_STRIP
918 ifeq ($(INSTALL_MOD_STRIP),1)
919 mod_strip_cmd = $(STRIP) --strip-debug
921 mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
922 endif # INSTALL_MOD_STRIP=1
925 endif # INSTALL_MOD_STRIP
928 # CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
929 # after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
930 # or CONFIG_MODULE_COMPRESS_XZ.
932 mod_compress_cmd = true
933 ifdef CONFIG_MODULE_COMPRESS
934 ifdef CONFIG_MODULE_COMPRESS_GZIP
935 mod_compress_cmd = gzip -n -f
936 endif # CONFIG_MODULE_COMPRESS_GZIP
937 ifdef CONFIG_MODULE_COMPRESS_XZ
938 mod_compress_cmd = xz -f
939 endif # CONFIG_MODULE_COMPRESS_XZ
940 endif # CONFIG_MODULE_COMPRESS
941 export mod_compress_cmd
943 # Select initial ramdisk compression format, default is gzip(1).
944 # This shall be used by the dracut(8) tool while creating an initramfs image.
946 INITRD_COMPRESS-y := gzip
947 INITRD_COMPRESS-$(CONFIG_RD_BZIP2) := bzip2
948 INITRD_COMPRESS-$(CONFIG_RD_LZMA) := lzma
949 INITRD_COMPRESS-$(CONFIG_RD_XZ) := xz
950 INITRD_COMPRESS-$(CONFIG_RD_LZO) := lzo
951 INITRD_COMPRESS-$(CONFIG_RD_LZ4) := lz4
952 # do not export INITRD_COMPRESS, since we didn't actually
953 # choose a sane default compression above.
954 # export INITRD_COMPRESS := $(INITRD_COMPRESS-y)
956 ifdef CONFIG_MODULE_SIG_ALL
957 $(eval $(call config_filename,MODULE_SIG_KEY))
959 mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
965 ifdef CONFIG_STACK_VALIDATION
966 has_libelf := $(call try-run,\
967 echo "int main() {}" | $(HOSTCC) -xc -o /dev/null -lelf -,1,0)
968 ifeq ($(has_libelf),1)
969 objtool_target := tools/objtool FORCE
971 ifdef CONFIG_UNWINDER_ORC
972 $(error "Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel")
974 $(warning "Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel")
976 SKIP_STACK_VALIDATION := 1
977 export SKIP_STACK_VALIDATION
982 ifeq ($(KBUILD_EXTMOD),)
983 core-y += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
985 vmlinux-dirs := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
986 $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
987 $(net-y) $(net-m) $(libs-y) $(libs-m) $(virt-y)))
989 vmlinux-alldirs := $(sort $(vmlinux-dirs) $(patsubst %/,%,$(filter %/, \
990 $(init-) $(core-) $(drivers-) $(net-) $(libs-) $(virt-))))
992 init-y := $(patsubst %/, %/built-in.a, $(init-y))
993 core-y := $(patsubst %/, %/built-in.a, $(core-y))
994 drivers-y := $(patsubst %/, %/built-in.a, $(drivers-y))
995 net-y := $(patsubst %/, %/built-in.a, $(net-y))
996 libs-y1 := $(patsubst %/, %/lib.a, $(libs-y))
997 libs-y2 := $(patsubst %/, %/built-in.a, $(filter-out %.a, $(libs-y)))
998 virt-y := $(patsubst %/, %/built-in.a, $(virt-y))
1000 # Externally visible symbols (used by link-vmlinux.sh)
1001 export KBUILD_VMLINUX_INIT := $(head-y) $(init-y)
1002 export KBUILD_VMLINUX_MAIN := $(core-y) $(libs-y2) $(drivers-y) $(net-y) $(virt-y)
1003 export KBUILD_VMLINUX_LIBS := $(libs-y1)
1004 export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
1005 export LDFLAGS_vmlinux
1006 # used by scripts/package/Makefile
1007 export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) arch Documentation include samples scripts tools)
1009 vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_INIT) $(KBUILD_VMLINUX_MAIN) $(KBUILD_VMLINUX_LIBS)
1011 # Recurse until adjust_autoksyms.sh is satisfied
1012 PHONY += autoksyms_recursive
1013 autoksyms_recursive: $(vmlinux-deps)
1014 ifdef CONFIG_TRIM_UNUSED_KSYMS
1015 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1016 "$(MAKE) -f $(srctree)/Makefile vmlinux"
1019 # For the kernel to actually contain only the needed exported symbols,
1020 # we have to build modules as well to determine what those symbols are.
1021 # (this can be evaluated only once include/config/auto.conf has been included)
1022 ifdef CONFIG_TRIM_UNUSED_KSYMS
1026 autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1029 $(Q)mkdir -p $(dir $@)
1032 ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1034 # Final link of vmlinux with optional arch pass after final link
1035 cmd_link-vmlinux = \
1036 $(CONFIG_SHELL) $< $(LD) $(KBUILD_LDFLAGS) $(LDFLAGS_vmlinux) ; \
1037 $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1039 vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1040 ifdef CONFIG_HEADERS_CHECK
1041 $(Q)$(MAKE) -f $(srctree)/Makefile headers_check
1043 ifdef CONFIG_GDB_SCRIPTS
1044 $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1046 +$(call if_changed,link-vmlinux)
1048 # Build samples along the rest of the kernel. This needs headers_install.
1049 ifdef CONFIG_SAMPLES
1050 vmlinux-dirs += samples
1051 samples: headers_install
1054 # The actual objects are generated when descending,
1055 # make sure no implicit rule kicks in
1056 $(sort $(vmlinux-deps)): $(vmlinux-dirs) ;
1058 # Handle descending into subdirectories listed in $(vmlinux-dirs)
1059 # Preset locale variables to speed up the build process. Limit locale
1060 # tweaks to this spot to avoid wrong language settings when running
1061 # make menuconfig etc.
1062 # Error messages still appears in the original language
1064 PHONY += $(vmlinux-dirs)
1065 $(vmlinux-dirs): prepare scripts
1066 $(Q)$(MAKE) $(build)=$@ need-builtin=1
1068 define filechk_kernel.release
1069 echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1072 # Store (new) KERNELRELEASE string in include/config/kernel.release
1073 include/config/kernel.release: $(srctree)/Makefile FORCE
1074 $(call filechk,kernel.release)
1076 # Additional helpers built in scripts/
1077 # Carefully list dependencies so we do not try to build scripts twice
1080 scripts: scripts_basic asm-generic gcc-plugins $(autoksyms_h)
1081 $(Q)$(MAKE) $(build)=$(@)
1083 # Things we need to do before we recursively start building the kernel
1084 # or the modules are listed in "prepare".
1085 # A multi level approach is used. prepareN is processed before prepareN-1.
1086 # archprepare is used in arch Makefiles and when processed asm symlink,
1087 # version.h and scripts_basic is processed / created.
1089 # Listed in dependency order
1090 PHONY += prepare archprepare prepare0 prepare1 prepare2 prepare3
1092 # prepare3 is used to check if we are building in a separate output directory,
1094 # 1) Check that make has not been executed in the kernel src $(srctree)
1095 prepare3: include/config/kernel.release
1096 ifneq ($(KBUILD_SRC),)
1097 @$(kecho) ' Using $(srctree) as source for kernel'
1098 $(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \
1099 echo >&2 " $(srctree) is not clean, please run 'make mrproper'"; \
1100 echo >&2 " in the '$(srctree)' directory.";\
1105 # prepare2 creates a makefile if using a separate output directory.
1106 # From this point forward, .config has been reprocessed, so any rules
1107 # that need to depend on updated CONFIG_* values can be checked here.
1108 prepare2: prepare3 outputmakefile asm-generic
1110 prepare1: prepare2 $(version_h) $(autoksyms_h) include/generated/utsrelease.h
1113 archprepare: archheaders archscripts prepare1 scripts_basic
1115 prepare0: archprepare gcc-plugins
1116 $(Q)$(MAKE) $(build)=.
1118 # All the preparing..
1119 prepare: prepare0 prepare-objtool
1121 # Support for using generic headers in asm-generic
1122 PHONY += asm-generic uapi-asm-generic
1123 asm-generic: uapi-asm-generic
1124 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
1125 src=asm obj=arch/$(SRCARCH)/include/generated/asm
1127 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
1128 src=uapi/asm obj=arch/$(SRCARCH)/include/generated/uapi/asm
1130 PHONY += prepare-objtool
1131 prepare-objtool: $(objtool_target)
1133 # Generate some files
1134 # ---------------------------------------------------------------------------
1136 # KERNELRELEASE can change from a few different places, meaning version.h
1137 # needs to be updated, so this check is forced on all builds
1140 define filechk_utsrelease.h
1141 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1142 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1145 (echo \#define UTS_RELEASE \"$(KERNELRELEASE)\";)
1148 define filechk_version.h
1149 (echo \#define LINUX_VERSION_CODE $(shell \
1150 expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1151 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))';)
1155 $(call filechk,version.h)
1156 $(Q)rm -f $(old_version_h)
1158 include/generated/utsrelease.h: include/config/kernel.release FORCE
1159 $(call filechk,utsrelease.h)
1163 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1164 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1166 # ---------------------------------------------------------------------------
1169 #Default location for installed headers
1170 export INSTALL_HDR_PATH = $(objtree)/usr
1172 # If we do an all arch process set dst to include/arch-$(SRCARCH)
1173 hdr-dst = $(if $(KBUILD_HEADERS), dst=include/arch-$(SRCARCH), dst=include)
1175 PHONY += archheaders
1178 PHONY += archscripts
1182 __headers: $(version_h) scripts_basic uapi-asm-generic archheaders archscripts
1183 $(Q)$(MAKE) $(build)=scripts build_unifdef
1185 PHONY += headers_install_all
1186 headers_install_all:
1187 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh install
1189 PHONY += headers_install
1190 headers_install: __headers
1191 $(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1192 $(error Headers not exportable for the $(SRCARCH) architecture))
1193 $(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include
1194 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi $(hdr-dst)
1196 PHONY += headers_check_all
1197 headers_check_all: headers_install_all
1198 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh check
1200 PHONY += headers_check
1201 headers_check: headers_install
1202 $(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include HDRCHECK=1
1203 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi $(hdr-dst) HDRCHECK=1
1205 # ---------------------------------------------------------------------------
1210 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1212 PHONY += kselftest-clean
1214 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests clean
1216 PHONY += kselftest-merge
1218 $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1219 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/kconfig/merge_config.sh \
1220 -m $(objtree)/.config \
1221 $(srctree)/tools/testing/selftests/*/config
1222 +$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1224 # ---------------------------------------------------------------------------
1227 ifdef CONFIG_MODULES
1229 # By default, build modules as well
1235 # A module can be listed more than once in obj-m resulting in
1236 # duplicate lines in modules.order files. Those are removed
1237 # using awk while concatenating to the final file.
1240 modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux) modules.builtin
1241 $(Q)$(AWK) '!x[$$0]++' $(vmlinux-dirs:%=$(objtree)/%/modules.order) > $(objtree)/modules.order
1242 @$(kecho) ' Building modules, stage 2.';
1243 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1245 modules.builtin: $(vmlinux-dirs:%=%/modules.builtin)
1246 $(Q)$(AWK) '!x[$$0]++' $^ > $(objtree)/modules.builtin
1248 %/modules.builtin: include/config/auto.conf include/config/tristate.conf
1249 $(Q)$(MAKE) $(modbuiltin)=$*
1252 # Target to prepare building external modules
1253 PHONY += modules_prepare
1254 modules_prepare: prepare scripts
1256 # Target to install modules
1257 PHONY += modules_install
1258 modules_install: _modinst_ _modinst_post
1262 @rm -rf $(MODLIB)/kernel
1263 @rm -f $(MODLIB)/source
1264 @mkdir -p $(MODLIB)/kernel
1265 @ln -s $(abspath $(srctree)) $(MODLIB)/source
1266 @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
1267 rm -f $(MODLIB)/build ; \
1268 ln -s $(CURDIR) $(MODLIB)/build ; \
1270 @cp -f $(objtree)/modules.order $(MODLIB)/
1271 @cp -f $(objtree)/modules.builtin $(MODLIB)/
1272 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1274 # This depmod is only for convenience to give the initial
1275 # boot a modules.dep even before / is mounted read-write. However the
1276 # boot script depmod is the master version.
1277 PHONY += _modinst_post
1278 _modinst_post: _modinst_
1281 ifeq ($(CONFIG_MODULE_SIG), y)
1282 PHONY += modules_sign
1284 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1287 else # CONFIG_MODULES
1289 # Modules not configured
1290 # ---------------------------------------------------------------------------
1292 PHONY += modules modules_install
1293 modules modules_install:
1295 @echo >&2 "The present kernel configuration has modules disabled."
1296 @echo >&2 "Type 'make config' and enable loadable module support."
1297 @echo >&2 "Then build a kernel with module support enabled."
1301 endif # CONFIG_MODULES
1304 # Cleaning is done on three levels.
1305 # make clean Delete most generated files
1306 # Leave enough to build external modules
1307 # make mrproper Delete the current configuration, and all generated files
1308 # make distclean Remove editor backup files, patch leftover files and the like
1310 # Directories & files removed with 'make clean'
1311 CLEAN_DIRS += $(MODVERDIR) include/ksym
1313 # Directories & files removed with 'make mrproper'
1314 MRPROPER_DIRS += include/config usr/include include/generated \
1315 arch/*/include/generated .tmp_objdiff
1316 MRPROPER_FILES += .config .config.old .version \
1317 Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS \
1318 signing_key.pem signing_key.priv signing_key.x509 \
1319 x509.genkey extra_certificates signing_key.x509.keyid \
1320 signing_key.x509.signer vmlinux-gdb.py
1322 # clean - Delete most, but leave enough to build external modules
1324 clean: rm-dirs := $(CLEAN_DIRS)
1325 clean: rm-files := $(CLEAN_FILES)
1326 clean-dirs := $(addprefix _clean_, . $(vmlinux-alldirs) Documentation samples)
1328 PHONY += $(clean-dirs) clean archclean vmlinuxclean
1330 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1333 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1334 $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1336 clean: archclean vmlinuxclean
1338 # mrproper - Delete all generated files, including .config
1340 mrproper: rm-dirs := $(wildcard $(MRPROPER_DIRS))
1341 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1342 mrproper-dirs := $(addprefix _mrproper_,scripts)
1344 PHONY += $(mrproper-dirs) mrproper archmrproper
1346 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1348 mrproper: clean archmrproper $(mrproper-dirs)
1357 @find $(srctree) $(RCS_FIND_IGNORE) \
1358 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1359 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1360 -o -name 'core' \) \
1361 -type f -print | xargs rm -f
1364 # Packaging of the kernel to various formats
1365 # ---------------------------------------------------------------------------
1366 package-dir := scripts/package
1369 $(Q)$(MAKE) $(build)=$(package-dir) $@
1370 %pkg: include/config/kernel.release FORCE
1371 $(Q)$(MAKE) $(build)=$(package-dir) $@
1374 # Brief documentation of the typical targets used
1375 # ---------------------------------------------------------------------------
1377 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1378 boards := $(sort $(notdir $(boards)))
1379 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1380 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1384 @echo 'Cleaning targets:'
1385 @echo ' clean - Remove most generated files but keep the config and'
1386 @echo ' enough build support to build external modules'
1387 @echo ' mrproper - Remove all generated files + config + various backup files'
1388 @echo ' distclean - mrproper + remove editor backup and patch files'
1390 @echo 'Configuration targets:'
1391 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1393 @echo 'Other generic targets:'
1394 @echo ' all - Build all targets marked with [*]'
1395 @echo '* vmlinux - Build the bare kernel'
1396 @echo '* modules - Build all modules'
1397 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1398 @echo ' dir/ - Build all files in dir and below'
1399 @echo ' dir/file.[ois] - Build specified target only'
1400 @echo ' dir/file.ll - Build the LLVM assembly file'
1401 @echo ' (requires compiler support for LLVM assembly generation)'
1402 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1403 @echo ' (requires a recent binutils and recent build (System.map))'
1404 @echo ' dir/file.ko - Build module including final link'
1405 @echo ' modules_prepare - Set up for building external modules'
1406 @echo ' tags/TAGS - Generate tags file for editors'
1407 @echo ' cscope - Generate cscope index'
1408 @echo ' gtags - Generate GNU GLOBAL index'
1409 @echo ' kernelrelease - Output the release version string (use with make -s)'
1410 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1411 @echo ' image_name - Output the image name (use with make -s)'
1412 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1413 echo ' (default: $(INSTALL_HDR_PATH))'; \
1415 @echo 'Static analysers:'
1416 @echo ' checkstack - Generate a list of stack hogs'
1417 @echo ' namespacecheck - Name space analysis on compiled kernel'
1418 @echo ' versioncheck - Sanity check on version.h usage'
1419 @echo ' includecheck - Check for duplicate included header files'
1420 @echo ' export_report - List the usages of all exported symbols'
1421 @echo ' headers_check - Sanity check on exported headers'
1422 @echo ' headerdep - Detect inclusion cycles in headers'
1423 @echo ' coccicheck - Check with Coccinelle'
1425 @echo 'Kernel selftest:'
1426 @echo ' kselftest - Build and run kernel selftest (run as root)'
1427 @echo ' Build, install, and boot kernel before'
1428 @echo ' running kselftest on it'
1429 @echo ' kselftest-clean - Remove all generated kselftest files'
1430 @echo ' kselftest-merge - Merge all the config dependencies of kselftest to existing'
1433 @echo 'Userspace tools targets:'
1434 @echo ' use "make tools/help"'
1435 @echo ' or "cd tools; make help"'
1437 @echo 'Kernel packaging:'
1438 @$(MAKE) $(build)=$(package-dir) help
1440 @echo 'Documentation targets:'
1441 @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1443 @echo 'Architecture specific targets ($(SRCARCH)):'
1444 @$(if $(archhelp),$(archhelp),\
1445 echo ' No architecture specific help defined for $(SRCARCH)')
1448 $(foreach b, $(boards), \
1449 printf " %-24s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1451 @$(if $(board-dirs), \
1452 $(foreach b, $(board-dirs), \
1453 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1454 printf " %-16s - Show all of the above\\n" help-boards; \
1457 @echo ' make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1458 @echo ' make V=2 [targets] 2 => give reason for rebuild of target'
1459 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1460 @echo ' make C=1 [targets] Check re-compiled c source with $$CHECK (sparse by default)'
1461 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1462 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1463 @echo ' make W=n [targets] Enable extra gcc checks, n=1,2,3 where'
1464 @echo ' 1: warnings which may be relevant and do not occur too often'
1465 @echo ' 2: warnings which occur quite often but may still be relevant'
1466 @echo ' 3: more obscure warnings, can most likely be ignored'
1467 @echo ' Multiple levels can be combined with W=12 or W=123'
1469 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1470 @echo 'For further info see the ./README file'
1473 help-board-dirs := $(addprefix help-,$(board-dirs))
1475 help-boards: $(help-board-dirs)
1477 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1479 $(help-board-dirs): help-%:
1480 @echo 'Architecture specific targets ($(SRCARCH) $*):'
1481 @$(if $(boards-per-dir), \
1482 $(foreach b, $(boards-per-dir), \
1483 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1487 # Documentation targets
1488 # ---------------------------------------------------------------------------
1489 DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1490 linkcheckdocs dochelp refcheckdocs
1491 PHONY += $(DOC_TARGETS)
1492 $(DOC_TARGETS): scripts_basic FORCE
1493 $(Q)$(MAKE) $(build)=Documentation $@
1495 else # KBUILD_EXTMOD
1498 # External module support.
1499 # When building external modules the kernel used as basis is considered
1500 # read-only, and no consistency checks are made and the make
1501 # system is not used on the basis kernel. If updates are required
1502 # in the basis kernel ordinary make commands (without M=...) must
1505 # The following are the only valid targets when building external
1507 # make M=dir clean Delete all automatically generated files
1508 # make M=dir modules Make all modules in specified dir
1509 # make M=dir Same as 'make M=dir modules'
1510 # make M=dir modules_install
1511 # Install the modules built in the module directory
1512 # Assumes install directory is already created
1514 # We are always building modules
1516 PHONY += crmodverdir
1520 PHONY += $(objtree)/Module.symvers
1521 $(objtree)/Module.symvers:
1522 @test -e $(objtree)/Module.symvers || ( \
1524 echo " WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1525 echo " is missing; modules will have no dependencies and modversions."; \
1528 module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
1529 PHONY += $(module-dirs) modules
1530 $(module-dirs): crmodverdir $(objtree)/Module.symvers
1531 $(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@)
1533 modules: $(module-dirs)
1534 @$(kecho) ' Building modules, stage 2.';
1535 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1537 PHONY += modules_install
1538 modules_install: _emodinst_ _emodinst_post
1540 install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1543 $(Q)mkdir -p $(MODLIB)/$(install-dir)
1544 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1546 PHONY += _emodinst_post
1547 _emodinst_post: _emodinst_
1550 clean-dirs := $(addprefix _clean_,$(KBUILD_EXTMOD))
1552 PHONY += $(clean-dirs) clean
1554 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1556 clean: rm-dirs := $(MODVERDIR)
1557 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers
1561 @echo ' Building external modules.'
1562 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1564 @echo ' modules - default target, build the module(s)'
1565 @echo ' modules_install - install the module'
1566 @echo ' clean - remove generated files in module directory only'
1570 PHONY += prepare scripts
1573 endif # KBUILD_EXTMOD
1575 clean: $(clean-dirs)
1578 @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1579 \( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1580 -o -name '*.ko.*' -o -name '*.dtb' -o -name '*.dtb.S' \
1581 -o -name '*.dwo' -o -name '*.lst' \
1583 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1584 -o -name '*.lex.c' -o -name '*.tab.[ch]' \
1585 -o -name '*.asn1.[ch]' \
1586 -o -name '*.symtypes' -o -name 'modules.order' \
1587 -o -name modules.builtin -o -name '.tmp_*.o.*' \
1588 -o -name '*.c.[012]*.*' \
1590 -o -name '*.gcno' \) -type f -print | xargs rm -f
1592 # Generate tags for editors
1593 # ---------------------------------------------------------------------------
1594 quiet_cmd_tags = GEN $@
1595 cmd_tags = $(CONFIG_SHELL) $(srctree)/scripts/tags.sh $@
1597 tags TAGS cscope gtags: FORCE
1600 # Scripts to check various things for consistency
1601 # ---------------------------------------------------------------------------
1603 PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1606 find $(srctree)/* $(RCS_FIND_IGNORE) \
1607 -name '*.[hcS]' -type f -print | sort \
1608 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1611 find $(srctree)/* $(RCS_FIND_IGNORE) \
1612 -name '*.[hcS]' -type f -print | sort \
1613 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1616 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/$@
1619 $(PERL) $(srctree)/scripts/namespace.pl
1622 $(PERL) $(srctree)/scripts/export_report.pl
1624 PHONY += checkstack kernelrelease kernelversion image_name
1626 # UML needs a little special treatment here. It wants to use the host
1627 # toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
1628 # else wants $(ARCH), including people doing cross-builds, which means
1629 # that $(SUBARCH) doesn't work here.
1631 CHECKSTACK_ARCH := $(SUBARCH)
1633 CHECKSTACK_ARCH := $(ARCH)
1636 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1637 $(PERL) $(src)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1640 @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1643 @echo $(KERNELVERSION)
1646 @echo $(KBUILD_IMAGE)
1648 # Clear a bunch of variables before executing the submake
1650 $(Q)mkdir -p $(objtree)/tools
1651 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(src)/tools/
1654 $(Q)mkdir -p $(objtree)/tools
1655 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(src)/tools/ $*
1658 # ---------------------------------------------------------------------------
1659 # Single targets are compatible with:
1660 # - build with mixed source and output
1661 # - build with separate output dir 'make O=...'
1662 # - external modules
1664 # target-dir => where to store outputfile
1665 # build-dir => directory in kernel source tree to use
1667 ifeq ($(KBUILD_EXTMOD),)
1668 build-dir = $(patsubst %/,%,$(dir $@))
1669 target-dir = $(dir $@)
1671 zap-slash=$(filter-out .,$(patsubst %/,%,$(dir $@)))
1672 build-dir = $(KBUILD_EXTMOD)$(if $(zap-slash),/$(zap-slash))
1673 target-dir = $(if $(KBUILD_EXTMOD),$(dir $<),$(dir $@))
1676 %.s: %.c prepare scripts FORCE
1677 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1678 %.i: %.c prepare scripts FORCE
1679 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1680 %.o: %.c prepare scripts FORCE
1681 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1682 %.lst: %.c prepare scripts FORCE
1683 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1684 %.s: %.S prepare scripts FORCE
1685 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1686 %.o: %.S prepare scripts FORCE
1687 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1688 %.symtypes: %.c prepare scripts FORCE
1689 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1690 %.ll: %.c prepare scripts FORCE
1691 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1694 /: prepare scripts FORCE
1696 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1697 $(build)=$(build-dir)
1698 # Make sure the latest headers are built for Documentation
1699 Documentation/ samples/: headers_install
1700 %/: prepare scripts FORCE
1702 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1703 $(build)=$(build-dir)
1704 %.ko: prepare scripts FORCE
1706 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1707 $(build)=$(build-dir) $(@:.ko=.o)
1708 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1710 # FIXME Should go into a make.lib or something
1711 # ===========================================================================
1713 quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN $(wildcard $(rm-dirs)))
1714 cmd_rmdirs = rm -rf $(rm-dirs)
1716 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
1717 cmd_rmfiles = rm -f $(rm-files)
1719 # Run depmod only if we have System.map and depmod is executable
1720 quiet_cmd_depmod = DEPMOD $(KERNELRELEASE)
1721 cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1724 # Create temporary dir for module support files
1725 # clean it up only when building all modules
1726 cmd_crmodverdir = $(Q)mkdir -p $(MODVERDIR) \
1727 $(if $(KBUILD_MODULES),; rm -f $(MODVERDIR)/*)
1729 # read all saved command lines
1730 cmd_files := $(wildcard .*.cmd)
1732 ifneq ($(cmd_files),)
1733 $(cmd_files): ; # Do not try to update included dependency files
1734 include $(cmd_files)
1737 endif # ifeq ($(config-targets),1)
1738 endif # ifeq ($(mixed-targets),1)
1739 endif # skip-makefile
1744 # Declare the contents of the PHONY variable as phony. We keep that
1745 # information in a variable so we can use it in if_changed and friends.