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 # o Do not use make's built-in rules and variables
19 # (this increases performance and avoids hard-to-debug behaviour);
20 # o Look for make include files relative to root of kernel src
21 MAKEFLAGS += -rR --include-dir=$(CURDIR)
23 # Avoid funny character set dependencies
27 export LC_COLLATE LC_NUMERIC
29 # Avoid interference with shell env settings
32 # We are using a recursive build, so we need to do a little thinking
33 # to get the ordering right.
35 # Most importantly: sub-Makefiles should only ever modify files in
36 # their own directory. If in some directory we have a dependency on
37 # a file in another dir (which doesn't happen often, but it's often
38 # unavoidable when linking the built-in.a targets which finally
39 # turn into vmlinux), we will call a sub make in that other dir, and
40 # after that we are sure that everything which is in that other dir
43 # The only cases where we need to modify files which have global
44 # effects are thus separated out and done before the recursive
45 # descending is started. They are now explicitly listed as the
49 # ---------------------------------------------------------------------------
51 # Normally, we echo the whole command before executing it. By making
52 # that echo $($(quiet)$(cmd)), we now have the possibility to set
53 # $(quiet) to choose other forms of output instead, e.g.
55 # quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
56 # cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
58 # If $(quiet) is empty, the whole command will be printed.
59 # If it is set to "quiet_", only the short version will be printed.
60 # If it is set to "silent_", nothing will be printed at all, since
61 # the variable $(silent_cmd_cc_o_c) doesn't exist.
63 # A simple variant is to prefix commands with $(Q) - that's useful
64 # for commands that shall be hidden in non-verbose mode.
68 # If KBUILD_VERBOSE equals 0 then the above command will be hidden.
69 # If KBUILD_VERBOSE equals 1 then the above command is displayed.
71 # To put more focus on warnings, be less verbose as default
72 # Use 'make V=1' to see the full commands
74 ifeq ("$(origin V)", "command line")
81 ifeq ($(KBUILD_VERBOSE),1)
89 # If the user is running make -s (silent mode), suppress echoing of
92 ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
97 export quiet Q KBUILD_VERBOSE
99 # kbuild supports saving output files in a separate directory.
100 # To locate output files in a separate directory two syntaxes are supported.
101 # In both cases the working directory must be the root of the kernel src.
103 # Use "make O=dir/to/store/output/files/"
105 # 2) Set KBUILD_OUTPUT
106 # Set the environment variable KBUILD_OUTPUT to point to the directory
107 # where the output files shall be placed.
108 # export KBUILD_OUTPUT=dir/to/store/output/files/
111 # The O= assignment takes precedence over the KBUILD_OUTPUT environment
114 # KBUILD_SRC is not intended to be used by the regular user (for now),
115 # it is set on invocation of make with KBUILD_OUTPUT or O= specified.
116 ifeq ($(KBUILD_SRC),)
118 # OK, Make called in directory where kernel src resides
119 # Do we want to locate output files in a separate directory?
120 ifeq ("$(origin O)", "command line")
121 KBUILD_OUTPUT := $(O)
124 # Cancel implicit rules on top Makefile
125 $(CURDIR)/Makefile Makefile: ;
127 ifneq ($(words $(subst :, ,$(CURDIR))), 1)
128 $(error main directory cannot contain spaces nor colons)
131 ifneq ($(KBUILD_OUTPUT),)
132 # check that the output directory actually exists
133 saved-output := $(KBUILD_OUTPUT)
134 KBUILD_OUTPUT := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) \
136 $(if $(KBUILD_OUTPUT),, \
137 $(error failed to create output directory "$(saved-output)"))
139 PHONY += $(MAKECMDGOALS) sub-make
141 $(filter-out _all sub-make $(CURDIR)/Makefile, $(MAKECMDGOALS)) _all: sub-make
144 # Invoke a second make in the output directory, passing relevant variables
146 $(Q)$(MAKE) -C $(KBUILD_OUTPUT) KBUILD_SRC=$(CURDIR) \
147 -f $(CURDIR)/Makefile $(filter-out _all sub-make,$(MAKECMDGOALS))
149 # Leave processing to above invocation of make
151 endif # ifneq ($(KBUILD_OUTPUT),)
152 endif # ifeq ($(KBUILD_SRC),)
154 # We process the rest of the Makefile if this is the final invocation of make
155 ifeq ($(skip-makefile),)
157 # Do not print "Entering directory ...",
158 # but we want to display it when entering to the output directory
159 # so that IDEs/editors are able to understand relative filenames.
160 MAKEFLAGS += --no-print-directory
162 # Call a source code checker (by default, "sparse") as part of the
165 # Use 'make C=1' to enable checking of only re-compiled files.
166 # Use 'make C=2' to enable checking of *all* source files, regardless
167 # of whether they are re-compiled or not.
169 # See the file "Documentation/dev-tools/sparse.rst" for more details,
170 # including where to get the "sparse" utility.
172 ifeq ("$(origin C)", "command line")
173 KBUILD_CHECKSRC = $(C)
175 ifndef KBUILD_CHECKSRC
179 # Use make M=dir to specify directory of external module to build
180 # Old syntax make ... SUBDIRS=$PWD is still supported
181 # Setting the environment variable KBUILD_EXTMOD take precedence
183 KBUILD_EXTMOD ?= $(SUBDIRS)
186 ifeq ("$(origin M)", "command line")
187 KBUILD_EXTMOD := $(M)
190 ifeq ($(KBUILD_SRC),)
191 # building in the source tree
194 ifeq ($(KBUILD_SRC)/,$(dir $(CURDIR)))
195 # building in a subdirectory of the source tree
198 srctree := $(KBUILD_SRC)
202 export KBUILD_CHECKSRC KBUILD_EXTMOD KBUILD_SRC
208 VPATH := $(srctree)$(if $(KBUILD_EXTMOD),:$(KBUILD_EXTMOD))
210 export srctree objtree VPATH
212 # To make sure we do not include .config for any of the *config targets
213 # catch them early, and hand them over to scripts/kconfig/Makefile
214 # It is allowed to specify more targets when calling make, including
215 # mixing *config targets and build targets.
216 # For example 'make oldconfig all'.
217 # Detect when mixed targets is specified, and make a second invocation
218 # of make so .config is not included in this case either (for *config).
220 version_h := include/generated/uapi/linux/version.h
221 old_version_h := include/linux/version.h
223 clean-targets := %clean mrproper cleandocs
224 no-dot-config-targets := $(clean-targets) \
225 cscope gtags TAGS tags help% %docs check% coccicheck \
226 $(version_h) headers_% archheaders archscripts \
227 %asm-generic kernelversion %src-pkg
228 no-sync-config-targets := $(no-dot-config-targets) install %install \
236 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
237 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
242 ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
243 ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
248 ifneq ($(KBUILD_EXTMOD),)
252 ifeq ($(KBUILD_EXTMOD),)
253 ifneq ($(filter config %config,$(MAKECMDGOALS)),)
255 ifneq ($(words $(MAKECMDGOALS)),1)
261 # For "make -j clean all", "make -j mrproper defconfig all", etc.
262 ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
263 ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
268 # install and modules_install need also be processed one by one
269 ifneq ($(filter install,$(MAKECMDGOALS)),)
270 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
275 ifeq ($(mixed-targets),1)
276 # ===========================================================================
277 # We're called with mixed targets (*config and build targets).
278 # Handle them one by one.
280 PHONY += $(MAKECMDGOALS) __build_one_by_one
282 $(filter-out __build_one_by_one, $(MAKECMDGOALS)): __build_one_by_one
287 for i in $(MAKECMDGOALS); do \
288 $(MAKE) -f $(srctree)/Makefile $$i; \
293 # We need some generic definitions (do not try to remake the file).
294 scripts/Kbuild.include: ;
295 include scripts/Kbuild.include
297 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
298 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
299 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
300 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
302 include scripts/subarch.include
304 # Cross compiling and selecting different set of gcc/bin-utils
305 # ---------------------------------------------------------------------------
307 # When performing cross compilation for other architectures ARCH shall be set
308 # to the target architecture. (See arch/* for the possibilities).
309 # ARCH can be set during invocation of make:
311 # Another way is to have ARCH set in the environment.
312 # The default ARCH is the host where make is executed.
314 # CROSS_COMPILE specify the prefix used for all executables used
315 # during compilation. Only gcc and related bin-utils executables
316 # are prefixed with $(CROSS_COMPILE).
317 # CROSS_COMPILE can be set on the command line
318 # make CROSS_COMPILE=ia64-linux-
319 # Alternatively CROSS_COMPILE can be set in the environment.
320 # Default value for CROSS_COMPILE is not to prefix executables
321 # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
324 # Architecture as present in compile.h
325 UTS_MACHINE := $(ARCH)
328 # Additional ARCH settings for x86
332 ifeq ($(ARCH),x86_64)
336 # Additional ARCH settings for sparc
337 ifeq ($(ARCH),sparc32)
340 ifeq ($(ARCH),sparc64)
344 # Additional ARCH settings for sh
349 KCONFIG_CONFIG ?= .config
350 export KCONFIG_CONFIG
352 # SHELL used by kbuild
353 CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
354 else if [ -x /bin/bash ]; then echo /bin/bash; \
355 else echo sh; fi ; fi)
357 HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
358 HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
359 HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
363 KBUILD_HOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 \
364 -fomit-frame-pointer -std=gnu89 $(HOST_LFS_CFLAGS) \
366 KBUILD_HOSTCXXFLAGS := -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
367 KBUILD_HOSTLDFLAGS := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
368 KBUILD_HOSTLDLIBS := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
370 # Make variables (CC, etc...)
371 AS = $(CROSS_COMPILE)as
372 LD = $(CROSS_COMPILE)ld
373 CC = $(CROSS_COMPILE)gcc
375 AR = $(CROSS_COMPILE)ar
376 NM = $(CROSS_COMPILE)nm
377 STRIP = $(CROSS_COMPILE)strip
378 OBJCOPY = $(CROSS_COMPILE)objcopy
379 OBJDUMP = $(CROSS_COMPILE)objdump
383 GENKSYMS = scripts/genksyms/genksyms
384 INSTALLKERNEL := installkernel
385 DEPMOD = /sbin/depmod
392 CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
393 -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
402 # Use USERINCLUDE when you must reference the UAPI directories only.
404 -I$(srctree)/arch/$(SRCARCH)/include/uapi \
405 -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
406 -I$(srctree)/include/uapi \
407 -I$(objtree)/include/generated/uapi \
408 -include $(srctree)/include/linux/kconfig.h
410 # Use LINUXINCLUDE when you must reference the include/ directory.
411 # Needed to be compatible with the O= option
413 -I$(srctree)/arch/$(SRCARCH)/include \
414 -I$(objtree)/arch/$(SRCARCH)/include/generated \
415 $(if $(KBUILD_SRC), -I$(srctree)/include) \
416 -I$(objtree)/include \
419 KBUILD_AFLAGS := -D__ASSEMBLY__
420 KBUILD_CFLAGS := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
421 -fno-strict-aliasing -fno-common -fshort-wchar \
422 -Werror-implicit-function-declaration \
423 -Wno-format-security \
425 KBUILD_CPPFLAGS := -D__KERNEL__
426 KBUILD_AFLAGS_KERNEL :=
427 KBUILD_CFLAGS_KERNEL :=
428 KBUILD_AFLAGS_MODULE := -DMODULE
429 KBUILD_CFLAGS_MODULE := -DMODULE
430 KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
432 GCC_PLUGINS_CFLAGS :=
434 export ARCH SRCARCH CONFIG_SHELL HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE AS LD CC
435 export CPP AR NM STRIP OBJCOPY OBJDUMP KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS
436 export MAKE LEX YACC AWK GENKSYMS INSTALLKERNEL PERL PYTHON PYTHON2 PYTHON3 UTS_MACHINE
437 export HOSTCXX KBUILD_HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
439 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
440 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
441 export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN
442 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
443 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
444 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
445 export KBUILD_ARFLAGS
447 # When compiling out-of-tree modules, put MODVERDIR in the module
448 # tree rather than in the kernel tree. The kernel tree might
450 export MODVERDIR := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_versions
452 # Files to ignore in find ... statements
454 export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o \
455 -name CVS -o -name .pc -o -name .hg -o -name .git \) \
457 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
458 --exclude CVS --exclude .pc --exclude .hg --exclude .git
460 # ===========================================================================
461 # Rules shared between *config targets and build targets
463 # Basic helpers built in scripts/basic/
464 PHONY += scripts_basic
466 $(Q)$(MAKE) $(build)=scripts/basic
467 $(Q)rm -f .tmp_quiet_recordmcount
469 # To avoid any implicit rule to kick in, define an empty command.
470 scripts/basic/%: scripts_basic ;
472 PHONY += outputmakefile
473 # outputmakefile generates a Makefile in the output directory, if using a
474 # separate output directory. This allows convenient use of make in the
477 ifneq ($(KBUILD_SRC),)
478 $(Q)ln -fsn $(srctree) source
479 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile \
480 $(srctree) $(objtree) $(VERSION) $(PATCHLEVEL)
483 ifeq ($(cc-name),clang)
484 ifneq ($(CROSS_COMPILE),)
485 CLANG_TARGET := --target=$(notdir $(CROSS_COMPILE:%-=%))
486 GCC_TOOLCHAIN := $(realpath $(dir $(shell which $(LD)))/..)
488 ifneq ($(GCC_TOOLCHAIN),)
489 CLANG_GCC_TC := --gcc-toolchain=$(GCC_TOOLCHAIN)
491 KBUILD_CFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC)
492 KBUILD_AFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC)
493 KBUILD_CFLAGS += $(call cc-option, -no-integrated-as)
494 KBUILD_AFLAGS += $(call cc-option, -no-integrated-as)
497 RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
498 RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
499 RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
500 RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
501 RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
502 RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
503 export RETPOLINE_CFLAGS
504 export RETPOLINE_VDSO_CFLAGS
506 KBUILD_CFLAGS += $(call cc-option,-fno-PIE)
507 KBUILD_AFLAGS += $(call cc-option,-fno-PIE)
509 # check for 'asm goto'
510 ifeq ($(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC) $(KBUILD_CFLAGS)), y)
511 CC_HAVE_ASM_GOTO := 1
512 KBUILD_CFLAGS += -DCC_HAVE_ASM_GOTO
513 KBUILD_AFLAGS += -DCC_HAVE_ASM_GOTO
516 # The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
517 # Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
518 # CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
519 # and from include/config/auto.conf.cmd to detect the compiler upgrade.
520 CC_VERSION_TEXT = $(shell $(CC) --version | head -n 1)
522 ifeq ($(config-targets),1)
523 # ===========================================================================
524 # *config targets only - make sure prerequisites are updated, and descend
525 # in scripts/kconfig to make the *config target
527 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
528 # KBUILD_DEFCONFIG may point out an alternative default configuration
529 # used for 'make defconfig'
530 include arch/$(SRCARCH)/Makefile
531 export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
533 config: scripts_basic outputmakefile FORCE
534 $(Q)$(MAKE) $(build)=scripts/kconfig $@
536 %config: scripts_basic outputmakefile FORCE
537 $(Q)$(MAKE) $(build)=scripts/kconfig $@
540 # ===========================================================================
541 # Build targets only - this includes vmlinux, arch specific targets, clean
542 # targets and others. In general all targets except *config targets.
544 # If building an external module we do not care about the all: rule
545 # but instead _all depend on modules
547 ifeq ($(KBUILD_EXTMOD),)
553 # Decide whether to build built-in, modular, or both.
554 # Normally, just do built-in.
559 # If we have only "make modules", don't compile built-in objects.
560 # When we're building modules with modversions, we need to consider
561 # the built-in objects during the descend as well, in order to
562 # make sure the checksums are up to date before we record them.
564 ifeq ($(MAKECMDGOALS),modules)
565 KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
568 # If we have "make <whatever> modules", compile modules
569 # in addition to whatever we do anyway.
570 # Just "make" or "make all" shall build modules as well
572 ifneq ($(filter all _all modules,$(MAKECMDGOALS)),)
576 ifeq ($(MAKECMDGOALS),)
580 export KBUILD_MODULES KBUILD_BUILTIN
582 ifeq ($(KBUILD_EXTMOD),)
583 # Objects we will link into vmlinux / subdirs we need to visit
585 drivers-y := drivers/ sound/ firmware/
590 endif # KBUILD_EXTMOD
592 ifeq ($(dot-config),1)
593 include include/config/auto.conf
596 # The all: target is the default when no target is given on the
598 # This allow a user to issue only 'make' to build a kernel including modules
599 # Defaults to vmlinux, but the arch makefile usually adds further targets
602 CFLAGS_GCOV := -fprofile-arcs -ftest-coverage \
603 $(call cc-option,-fno-tree-loop-im) \
604 $(call cc-disable-warning,maybe-uninitialized,)
607 # The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
608 ifdef CONFIG_FUNCTION_TRACER
609 CC_FLAGS_FTRACE := -pg
612 # The arch Makefile can set ARCH_{CPP,A,C}FLAGS to override the default
613 # values of the respective KBUILD_* variables
617 include arch/$(SRCARCH)/Makefile
619 ifeq ($(dot-config),1)
620 ifeq ($(may-sync-config),1)
621 # Read in dependencies to all Kconfig* files, make sure to run syncconfig if
622 # changes are detected. This should be included after arch/$(SRCARCH)/Makefile
623 # because some architectures define CROSS_COMPILE there.
624 -include include/config/auto.conf.cmd
626 # To avoid any implicit rule to kick in, define an empty command
627 $(KCONFIG_CONFIG) include/config/auto.conf.cmd: ;
629 # The actual configuration files used during the build are stored in
630 # include/generated/ and include/config/. Update them if .config is newer than
631 # include/config/auto.conf (which mirrors .config).
632 include/config/%.conf: $(KCONFIG_CONFIG) include/config/auto.conf.cmd
633 $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
635 # External modules and some install targets need include/generated/autoconf.h
636 # and include/config/auto.conf but do not care if they are up-to-date.
637 # Use auto.conf to trigger the test
638 PHONY += include/config/auto.conf
640 include/config/auto.conf:
641 $(Q)test -e include/generated/autoconf.h -a -e $@ || ( \
643 echo >&2 " ERROR: Kernel configuration is invalid."; \
644 echo >&2 " include/generated/autoconf.h or $@ are missing.";\
645 echo >&2 " Run 'make oldconfig && make prepare' on kernel src to fix it."; \
649 endif # may-sync-config
650 endif # $(dot-config)
652 KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,)
653 KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,)
654 KBUILD_CFLAGS += $(call cc-disable-warning, format-truncation)
655 KBUILD_CFLAGS += $(call cc-disable-warning, format-overflow)
656 KBUILD_CFLAGS += $(call cc-disable-warning, int-in-bool-context)
658 ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
659 KBUILD_CFLAGS += $(call cc-option,-Oz,-Os)
660 KBUILD_CFLAGS += $(call cc-disable-warning,maybe-uninitialized,)
662 ifdef CONFIG_PROFILE_ALL_BRANCHES
663 KBUILD_CFLAGS += -O2 $(call cc-disable-warning,maybe-uninitialized,)
669 KBUILD_CFLAGS += $(call cc-ifversion, -lt, 0409, \
670 $(call cc-disable-warning,maybe-uninitialized,))
672 # Tell gcc to never replace conditional load with a non-conditional one
673 KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
675 include scripts/Makefile.kcov
676 include scripts/Makefile.gcc-plugins
678 ifdef CONFIG_READABLE_ASM
679 # Disable optimizations that make assembler listings hard to read.
680 # reorder blocks reorders the control in the function
681 # ipa clone creates specialized cloned functions
682 # partial inlining inlines only parts of functions
683 KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
684 $(call cc-option,-fno-ipa-cp-clone,) \
685 $(call cc-option,-fno-partial-inlining)
688 ifneq ($(CONFIG_FRAME_WARN),0)
689 KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
692 stackp-flags-$(CONFIG_CC_HAS_STACKPROTECTOR_NONE) := -fno-stack-protector
693 stackp-flags-$(CONFIG_STACKPROTECTOR) := -fstack-protector
694 stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG) := -fstack-protector-strong
696 KBUILD_CFLAGS += $(stackp-flags-y)
698 ifeq ($(cc-name),clang)
699 KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
700 KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier)
701 KBUILD_CFLAGS += $(call cc-disable-warning, gnu)
702 KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
703 # Quiet clang warning: comparison of unsigned expression < 0 is always false
704 KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare)
705 # CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
706 # source of a reference will be _MergedGlobals and not on of the whitelisted names.
707 # See modpost pattern 2
708 KBUILD_CFLAGS += $(call cc-option, -mno-global-merge,)
709 KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior)
712 # These warnings generated too much noise in a regular build.
713 # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
714 KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
717 KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
718 ifdef CONFIG_FRAME_POINTER
719 KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
721 # Some targets (ARM with Thumb2, for example), can't be built with frame
722 # pointers. For those, we don't have FUNCTION_TRACER automatically
723 # select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
724 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
725 # -fomit-frame-pointer with FUNCTION_TRACER.
726 ifndef CONFIG_FUNCTION_TRACER
727 KBUILD_CFLAGS += -fomit-frame-pointer
731 KBUILD_CFLAGS += $(call cc-option, -fno-var-tracking-assignments)
733 ifdef CONFIG_DEBUG_INFO
734 ifdef CONFIG_DEBUG_INFO_SPLIT
735 KBUILD_CFLAGS += $(call cc-option, -gsplit-dwarf, -g)
739 KBUILD_AFLAGS += -Wa,-gdwarf-2
741 ifdef CONFIG_DEBUG_INFO_DWARF4
742 KBUILD_CFLAGS += $(call cc-option, -gdwarf-4,)
745 ifdef CONFIG_DEBUG_INFO_REDUCED
746 KBUILD_CFLAGS += $(call cc-option, -femit-struct-debug-baseonly) \
747 $(call cc-option,-fno-var-tracking)
750 ifdef CONFIG_FUNCTION_TRACER
751 ifdef CONFIG_FTRACE_MCOUNT_RECORD
752 # gcc 5 supports generating the mcount tables directly
753 ifeq ($(call cc-option-yn,-mrecord-mcount),y)
754 CC_FLAGS_FTRACE += -mrecord-mcount
755 export CC_USING_RECORD_MCOUNT := 1
757 ifdef CONFIG_HAVE_NOP_MCOUNT
758 ifeq ($(call cc-option-yn, -mnop-mcount),y)
759 CC_FLAGS_FTRACE += -mnop-mcount
760 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
764 ifdef CONFIG_HAVE_FENTRY
765 ifeq ($(call cc-option-yn, -mfentry),y)
766 CC_FLAGS_FTRACE += -mfentry
767 CC_FLAGS_USING += -DCC_USING_FENTRY
770 export CC_FLAGS_FTRACE
771 KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
772 KBUILD_AFLAGS += $(CC_FLAGS_USING)
773 ifdef CONFIG_DYNAMIC_FTRACE
774 ifdef CONFIG_HAVE_C_RECORDMCOUNT
775 BUILD_C_RECORDMCOUNT := y
776 export BUILD_C_RECORDMCOUNT
781 # We trigger additional mismatches with less inlining
782 ifdef CONFIG_DEBUG_SECTION_MISMATCH
783 KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
786 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
787 KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
788 LDFLAGS_vmlinux += --gc-sections
791 # arch Makefile may override CC so keep this after arch Makefile is included
792 NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
794 # warn about C99 declaration after statement
795 KBUILD_CFLAGS += $(call cc-option,-Wdeclaration-after-statement,)
797 # disable pointer signed / unsigned warnings in gcc 4.0
798 KBUILD_CFLAGS += $(call cc-disable-warning, pointer-sign)
800 # disable stringop warnings in gcc 8+
801 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
803 # disable invalid "can't wrap" optimizations for signed / pointers
804 KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow)
806 # clang sets -fmerge-all-constants by default as optimization, but this
807 # is non-conforming behavior for C and in fact breaks the kernel, so we
808 # need to disable it here generally.
809 KBUILD_CFLAGS += $(call cc-option,-fno-merge-all-constants)
811 # for gcc -fno-merge-all-constants disables everything, but it is fine
812 # to have actual conforming behavior enabled.
813 KBUILD_CFLAGS += $(call cc-option,-fmerge-constants)
815 # Make sure -fstack-check isn't enabled (like gentoo apparently did)
816 KBUILD_CFLAGS += $(call cc-option,-fno-stack-check,)
818 # conserve stack if available
819 KBUILD_CFLAGS += $(call cc-option,-fconserve-stack)
821 # disallow errors like 'EXPORT_GPL(foo);' with missing header
822 KBUILD_CFLAGS += $(call cc-option,-Werror=implicit-int)
824 # require functions to have arguments in prototypes, not empty 'int foo()'
825 KBUILD_CFLAGS += $(call cc-option,-Werror=strict-prototypes)
827 # Prohibit date/time macros, which would make the build non-deterministic
828 KBUILD_CFLAGS += $(call cc-option,-Werror=date-time)
830 # enforce correct pointer usage
831 KBUILD_CFLAGS += $(call cc-option,-Werror=incompatible-pointer-types)
833 # Require designated initializers for all marked structures
834 KBUILD_CFLAGS += $(call cc-option,-Werror=designated-init)
836 # change __FILE__ to the relative path from the srctree
837 KBUILD_CFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
839 # use the deterministic mode of AR if available
840 KBUILD_ARFLAGS := $(call ar-option,D)
842 include scripts/Makefile.kasan
843 include scripts/Makefile.extrawarn
844 include scripts/Makefile.ubsan
846 # Add any arch overrides and user supplied CPPFLAGS, AFLAGS and CFLAGS as the
848 KBUILD_CPPFLAGS += $(ARCH_CPPFLAGS) $(KCPPFLAGS)
849 KBUILD_AFLAGS += $(ARCH_AFLAGS) $(KAFLAGS)
850 KBUILD_CFLAGS += $(ARCH_CFLAGS) $(KCFLAGS)
852 # Use --build-id when available.
853 LDFLAGS_BUILD_ID := $(call ld-option, --build-id)
854 KBUILD_LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID)
855 LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)
857 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
858 LDFLAGS_vmlinux += $(call ld-option, -X,)
861 # insure the checker run with the right endianness
862 CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
864 # the checker needs the correct machine size
865 CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
867 # Default kernel image to build when no specific target is given.
868 # KBUILD_IMAGE may be overruled on the command line or
869 # set in the environment
870 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
872 export KBUILD_IMAGE ?= vmlinux
875 # INSTALL_PATH specifies where to place the updated kernel and system map
876 # images. Default is /boot, but you can set it to other values
877 export INSTALL_PATH ?= /boot
880 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
881 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
882 # an argument if needed. Otherwise it defaults to the kernel install path
884 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
887 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
888 # relocations required by build roots. This is not defined in the
889 # makefile but the argument can be passed to make if needed.
892 MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
896 # INSTALL_MOD_STRIP, if defined, will cause modules to be
897 # stripped after they are installed. If INSTALL_MOD_STRIP is '1', then
898 # the default option --strip-debug will be used. Otherwise,
899 # INSTALL_MOD_STRIP value will be used as the options to the strip command.
901 ifdef INSTALL_MOD_STRIP
902 ifeq ($(INSTALL_MOD_STRIP),1)
903 mod_strip_cmd = $(STRIP) --strip-debug
905 mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
906 endif # INSTALL_MOD_STRIP=1
909 endif # INSTALL_MOD_STRIP
912 # CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
913 # after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
914 # or CONFIG_MODULE_COMPRESS_XZ.
916 mod_compress_cmd = true
917 ifdef CONFIG_MODULE_COMPRESS
918 ifdef CONFIG_MODULE_COMPRESS_GZIP
919 mod_compress_cmd = gzip -n -f
920 endif # CONFIG_MODULE_COMPRESS_GZIP
921 ifdef CONFIG_MODULE_COMPRESS_XZ
922 mod_compress_cmd = xz -f
923 endif # CONFIG_MODULE_COMPRESS_XZ
924 endif # CONFIG_MODULE_COMPRESS
925 export mod_compress_cmd
927 # Select initial ramdisk compression format, default is gzip(1).
928 # This shall be used by the dracut(8) tool while creating an initramfs image.
930 INITRD_COMPRESS-y := gzip
931 INITRD_COMPRESS-$(CONFIG_RD_BZIP2) := bzip2
932 INITRD_COMPRESS-$(CONFIG_RD_LZMA) := lzma
933 INITRD_COMPRESS-$(CONFIG_RD_XZ) := xz
934 INITRD_COMPRESS-$(CONFIG_RD_LZO) := lzo
935 INITRD_COMPRESS-$(CONFIG_RD_LZ4) := lz4
936 # do not export INITRD_COMPRESS, since we didn't actually
937 # choose a sane default compression above.
938 # export INITRD_COMPRESS := $(INITRD_COMPRESS-y)
940 ifdef CONFIG_MODULE_SIG_ALL
941 $(eval $(call config_filename,MODULE_SIG_KEY))
943 mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
949 ifdef CONFIG_STACK_VALIDATION
950 has_libelf := $(call try-run,\
951 echo "int main() {}" | $(HOSTCC) -xc -o /dev/null -lelf -,1,0)
952 ifeq ($(has_libelf),1)
953 objtool_target := tools/objtool FORCE
955 ifdef CONFIG_UNWINDER_ORC
956 $(error "Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel")
958 $(warning "Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel")
960 SKIP_STACK_VALIDATION := 1
961 export SKIP_STACK_VALIDATION
966 ifeq ($(KBUILD_EXTMOD),)
967 core-y += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
969 vmlinux-dirs := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
970 $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
971 $(net-y) $(net-m) $(libs-y) $(libs-m) $(virt-y)))
973 vmlinux-alldirs := $(sort $(vmlinux-dirs) $(patsubst %/,%,$(filter %/, \
974 $(init-) $(core-) $(drivers-) $(net-) $(libs-) $(virt-))))
976 init-y := $(patsubst %/, %/built-in.a, $(init-y))
977 core-y := $(patsubst %/, %/built-in.a, $(core-y))
978 drivers-y := $(patsubst %/, %/built-in.a, $(drivers-y))
979 net-y := $(patsubst %/, %/built-in.a, $(net-y))
980 libs-y1 := $(patsubst %/, %/lib.a, $(libs-y))
981 libs-y2 := $(patsubst %/, %/built-in.a, $(filter-out %.a, $(libs-y)))
982 virt-y := $(patsubst %/, %/built-in.a, $(virt-y))
984 # Externally visible symbols (used by link-vmlinux.sh)
985 export KBUILD_VMLINUX_INIT := $(head-y) $(init-y)
986 export KBUILD_VMLINUX_MAIN := $(core-y) $(libs-y2) $(drivers-y) $(net-y) $(virt-y)
987 export KBUILD_VMLINUX_LIBS := $(libs-y1)
988 export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
989 export LDFLAGS_vmlinux
990 # used by scripts/package/Makefile
991 export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) arch Documentation include samples scripts tools)
993 vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_INIT) $(KBUILD_VMLINUX_MAIN) $(KBUILD_VMLINUX_LIBS)
995 # Recurse until adjust_autoksyms.sh is satisfied
996 PHONY += autoksyms_recursive
997 autoksyms_recursive: $(vmlinux-deps)
998 ifdef CONFIG_TRIM_UNUSED_KSYMS
999 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1000 "$(MAKE) -f $(srctree)/Makefile vmlinux"
1003 # For the kernel to actually contain only the needed exported symbols,
1004 # we have to build modules as well to determine what those symbols are.
1005 # (this can be evaluated only once include/config/auto.conf has been included)
1006 ifdef CONFIG_TRIM_UNUSED_KSYMS
1010 autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1013 $(Q)mkdir -p $(dir $@)
1016 ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1018 # Final link of vmlinux with optional arch pass after final link
1019 cmd_link-vmlinux = \
1020 $(CONFIG_SHELL) $< $(LD) $(KBUILD_LDFLAGS) $(LDFLAGS_vmlinux) ; \
1021 $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1023 vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1024 ifdef CONFIG_HEADERS_CHECK
1025 $(Q)$(MAKE) -f $(srctree)/Makefile headers_check
1027 ifdef CONFIG_GDB_SCRIPTS
1028 $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1030 +$(call if_changed,link-vmlinux)
1032 # Build samples along the rest of the kernel. This needs headers_install.
1033 ifdef CONFIG_SAMPLES
1034 vmlinux-dirs += samples
1035 samples: headers_install
1038 # The actual objects are generated when descending,
1039 # make sure no implicit rule kicks in
1040 $(sort $(vmlinux-deps)): $(vmlinux-dirs) ;
1042 # Handle descending into subdirectories listed in $(vmlinux-dirs)
1043 # Preset locale variables to speed up the build process. Limit locale
1044 # tweaks to this spot to avoid wrong language settings when running
1045 # make menuconfig etc.
1046 # Error messages still appears in the original language
1048 PHONY += $(vmlinux-dirs)
1049 $(vmlinux-dirs): prepare scripts
1050 $(Q)$(MAKE) $(build)=$@ need-builtin=1
1052 define filechk_kernel.release
1053 echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1056 # Store (new) KERNELRELEASE string in include/config/kernel.release
1057 include/config/kernel.release: $(srctree)/Makefile FORCE
1058 $(call filechk,kernel.release)
1060 # Additional helpers built in scripts/
1061 # Carefully list dependencies so we do not try to build scripts twice
1064 scripts: scripts_basic asm-generic gcc-plugins $(autoksyms_h)
1065 $(Q)$(MAKE) $(build)=$(@)
1067 # Things we need to do before we recursively start building the kernel
1068 # or the modules are listed in "prepare".
1069 # A multi level approach is used. prepareN is processed before prepareN-1.
1070 # archprepare is used in arch Makefiles and when processed asm symlink,
1071 # version.h and scripts_basic is processed / created.
1073 # Listed in dependency order
1074 PHONY += prepare archprepare prepare0 prepare1 prepare2 prepare3
1076 # prepare3 is used to check if we are building in a separate output directory,
1078 # 1) Check that make has not been executed in the kernel src $(srctree)
1079 prepare3: include/config/kernel.release
1080 ifneq ($(KBUILD_SRC),)
1081 @$(kecho) ' Using $(srctree) as source for kernel'
1082 $(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \
1083 echo >&2 " $(srctree) is not clean, please run 'make mrproper'"; \
1084 echo >&2 " in the '$(srctree)' directory.";\
1089 # prepare2 creates a makefile if using a separate output directory.
1090 # From this point forward, .config has been reprocessed, so any rules
1091 # that need to depend on updated CONFIG_* values can be checked here.
1092 prepare2: prepare3 outputmakefile asm-generic
1094 prepare1: prepare2 $(version_h) $(autoksyms_h) include/generated/utsrelease.h
1097 archprepare: archheaders archscripts prepare1 scripts_basic
1099 prepare0: archprepare gcc-plugins
1100 $(Q)$(MAKE) $(build)=.
1102 # All the preparing..
1103 prepare: prepare0 prepare-objtool
1105 # Support for using generic headers in asm-generic
1106 PHONY += asm-generic uapi-asm-generic
1107 asm-generic: uapi-asm-generic
1108 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
1109 src=asm obj=arch/$(SRCARCH)/include/generated/asm
1111 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
1112 src=uapi/asm obj=arch/$(SRCARCH)/include/generated/uapi/asm
1114 PHONY += prepare-objtool
1115 prepare-objtool: $(objtool_target)
1117 # Generate some files
1118 # ---------------------------------------------------------------------------
1120 # KERNELRELEASE can change from a few different places, meaning version.h
1121 # needs to be updated, so this check is forced on all builds
1124 define filechk_utsrelease.h
1125 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1126 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1129 (echo \#define UTS_RELEASE \"$(KERNELRELEASE)\";)
1132 define filechk_version.h
1133 (echo \#define LINUX_VERSION_CODE $(shell \
1134 expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1135 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))';)
1139 $(call filechk,version.h)
1140 $(Q)rm -f $(old_version_h)
1142 include/generated/utsrelease.h: include/config/kernel.release FORCE
1143 $(call filechk,utsrelease.h)
1147 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1148 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1150 # ---------------------------------------------------------------------------
1153 #Default location for installed headers
1154 export INSTALL_HDR_PATH = $(objtree)/usr
1156 # If we do an all arch process set dst to include/arch-$(SRCARCH)
1157 hdr-dst = $(if $(KBUILD_HEADERS), dst=include/arch-$(SRCARCH), dst=include)
1159 PHONY += archheaders
1162 PHONY += archscripts
1166 __headers: $(version_h) scripts_basic uapi-asm-generic archheaders archscripts
1167 $(Q)$(MAKE) $(build)=scripts build_unifdef
1169 PHONY += headers_install_all
1170 headers_install_all:
1171 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh install
1173 PHONY += headers_install
1174 headers_install: __headers
1175 $(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1176 $(error Headers not exportable for the $(SRCARCH) architecture))
1177 $(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include
1178 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi $(hdr-dst)
1180 PHONY += headers_check_all
1181 headers_check_all: headers_install_all
1182 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh check
1184 PHONY += headers_check
1185 headers_check: headers_install
1186 $(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include HDRCHECK=1
1187 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi $(hdr-dst) HDRCHECK=1
1189 # ---------------------------------------------------------------------------
1194 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1196 PHONY += kselftest-clean
1198 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests clean
1200 PHONY += kselftest-merge
1202 $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1203 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/kconfig/merge_config.sh \
1204 -m $(objtree)/.config \
1205 $(srctree)/tools/testing/selftests/*/config
1206 +$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1208 # ---------------------------------------------------------------------------
1211 ifdef CONFIG_MODULES
1213 # By default, build modules as well
1219 # A module can be listed more than once in obj-m resulting in
1220 # duplicate lines in modules.order files. Those are removed
1221 # using awk while concatenating to the final file.
1224 modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux) modules.builtin
1225 $(Q)$(AWK) '!x[$$0]++' $(vmlinux-dirs:%=$(objtree)/%/modules.order) > $(objtree)/modules.order
1226 @$(kecho) ' Building modules, stage 2.';
1227 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1229 modules.builtin: $(vmlinux-dirs:%=%/modules.builtin)
1230 $(Q)$(AWK) '!x[$$0]++' $^ > $(objtree)/modules.builtin
1232 %/modules.builtin: include/config/auto.conf include/config/tristate.conf
1233 $(Q)$(MAKE) $(modbuiltin)=$*
1236 # Target to prepare building external modules
1237 PHONY += modules_prepare
1238 modules_prepare: prepare scripts
1240 # Target to install modules
1241 PHONY += modules_install
1242 modules_install: _modinst_ _modinst_post
1246 @rm -rf $(MODLIB)/kernel
1247 @rm -f $(MODLIB)/source
1248 @mkdir -p $(MODLIB)/kernel
1249 @ln -s $(abspath $(srctree)) $(MODLIB)/source
1250 @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
1251 rm -f $(MODLIB)/build ; \
1252 ln -s $(CURDIR) $(MODLIB)/build ; \
1254 @cp -f $(objtree)/modules.order $(MODLIB)/
1255 @cp -f $(objtree)/modules.builtin $(MODLIB)/
1256 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1258 # This depmod is only for convenience to give the initial
1259 # boot a modules.dep even before / is mounted read-write. However the
1260 # boot script depmod is the master version.
1261 PHONY += _modinst_post
1262 _modinst_post: _modinst_
1265 ifeq ($(CONFIG_MODULE_SIG), y)
1266 PHONY += modules_sign
1268 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1271 else # CONFIG_MODULES
1273 # Modules not configured
1274 # ---------------------------------------------------------------------------
1276 PHONY += modules modules_install
1277 modules modules_install:
1279 @echo >&2 "The present kernel configuration has modules disabled."
1280 @echo >&2 "Type 'make config' and enable loadable module support."
1281 @echo >&2 "Then build a kernel with module support enabled."
1285 endif # CONFIG_MODULES
1288 # Cleaning is done on three levels.
1289 # make clean Delete most generated files
1290 # Leave enough to build external modules
1291 # make mrproper Delete the current configuration, and all generated files
1292 # make distclean Remove editor backup files, patch leftover files and the like
1294 # Directories & files removed with 'make clean'
1295 CLEAN_DIRS += $(MODVERDIR) include/ksym
1297 # Directories & files removed with 'make mrproper'
1298 MRPROPER_DIRS += include/config usr/include include/generated \
1299 arch/*/include/generated .tmp_objdiff
1300 MRPROPER_FILES += .config .config.old .version \
1301 Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS \
1302 signing_key.pem signing_key.priv signing_key.x509 \
1303 x509.genkey extra_certificates signing_key.x509.keyid \
1304 signing_key.x509.signer vmlinux-gdb.py
1306 # clean - Delete most, but leave enough to build external modules
1308 clean: rm-dirs := $(CLEAN_DIRS)
1309 clean: rm-files := $(CLEAN_FILES)
1310 clean-dirs := $(addprefix _clean_, . $(vmlinux-alldirs) Documentation samples)
1312 PHONY += $(clean-dirs) clean archclean vmlinuxclean
1314 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1317 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1318 $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1320 clean: archclean vmlinuxclean
1322 # mrproper - Delete all generated files, including .config
1324 mrproper: rm-dirs := $(wildcard $(MRPROPER_DIRS))
1325 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1326 mrproper-dirs := $(addprefix _mrproper_,scripts)
1328 PHONY += $(mrproper-dirs) mrproper archmrproper
1330 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1332 mrproper: clean archmrproper $(mrproper-dirs)
1341 @find $(srctree) $(RCS_FIND_IGNORE) \
1342 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1343 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1344 -o -name 'core' \) \
1345 -type f -print | xargs rm -f
1348 # Packaging of the kernel to various formats
1349 # ---------------------------------------------------------------------------
1350 package-dir := scripts/package
1353 $(Q)$(MAKE) $(build)=$(package-dir) $@
1354 %pkg: include/config/kernel.release FORCE
1355 $(Q)$(MAKE) $(build)=$(package-dir) $@
1358 # Brief documentation of the typical targets used
1359 # ---------------------------------------------------------------------------
1361 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1362 boards := $(sort $(notdir $(boards)))
1363 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1364 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1368 @echo 'Cleaning targets:'
1369 @echo ' clean - Remove most generated files but keep the config and'
1370 @echo ' enough build support to build external modules'
1371 @echo ' mrproper - Remove all generated files + config + various backup files'
1372 @echo ' distclean - mrproper + remove editor backup and patch files'
1374 @echo 'Configuration targets:'
1375 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1377 @echo 'Other generic targets:'
1378 @echo ' all - Build all targets marked with [*]'
1379 @echo '* vmlinux - Build the bare kernel'
1380 @echo '* modules - Build all modules'
1381 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1382 @echo ' dir/ - Build all files in dir and below'
1383 @echo ' dir/file.[ois] - Build specified target only'
1384 @echo ' dir/file.ll - Build the LLVM assembly file'
1385 @echo ' (requires compiler support for LLVM assembly generation)'
1386 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1387 @echo ' (requires a recent binutils and recent build (System.map))'
1388 @echo ' dir/file.ko - Build module including final link'
1389 @echo ' modules_prepare - Set up for building external modules'
1390 @echo ' tags/TAGS - Generate tags file for editors'
1391 @echo ' cscope - Generate cscope index'
1392 @echo ' gtags - Generate GNU GLOBAL index'
1393 @echo ' kernelrelease - Output the release version string (use with make -s)'
1394 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1395 @echo ' image_name - Output the image name (use with make -s)'
1396 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1397 echo ' (default: $(INSTALL_HDR_PATH))'; \
1399 @echo 'Static analysers:'
1400 @echo ' checkstack - Generate a list of stack hogs'
1401 @echo ' namespacecheck - Name space analysis on compiled kernel'
1402 @echo ' versioncheck - Sanity check on version.h usage'
1403 @echo ' includecheck - Check for duplicate included header files'
1404 @echo ' export_report - List the usages of all exported symbols'
1405 @echo ' headers_check - Sanity check on exported headers'
1406 @echo ' headerdep - Detect inclusion cycles in headers'
1407 @echo ' coccicheck - Check with Coccinelle'
1409 @echo 'Kernel selftest:'
1410 @echo ' kselftest - Build and run kernel selftest (run as root)'
1411 @echo ' Build, install, and boot kernel before'
1412 @echo ' running kselftest on it'
1413 @echo ' kselftest-clean - Remove all generated kselftest files'
1414 @echo ' kselftest-merge - Merge all the config dependencies of kselftest to existing'
1417 @echo 'Userspace tools targets:'
1418 @echo ' use "make tools/help"'
1419 @echo ' or "cd tools; make help"'
1421 @echo 'Kernel packaging:'
1422 @$(MAKE) $(build)=$(package-dir) help
1424 @echo 'Documentation targets:'
1425 @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1427 @echo 'Architecture specific targets ($(SRCARCH)):'
1428 @$(if $(archhelp),$(archhelp),\
1429 echo ' No architecture specific help defined for $(SRCARCH)')
1432 $(foreach b, $(boards), \
1433 printf " %-24s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1435 @$(if $(board-dirs), \
1436 $(foreach b, $(board-dirs), \
1437 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1438 printf " %-16s - Show all of the above\\n" help-boards; \
1441 @echo ' make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1442 @echo ' make V=2 [targets] 2 => give reason for rebuild of target'
1443 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1444 @echo ' make C=1 [targets] Check re-compiled c source with $$CHECK (sparse by default)'
1445 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1446 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1447 @echo ' make W=n [targets] Enable extra gcc checks, n=1,2,3 where'
1448 @echo ' 1: warnings which may be relevant and do not occur too often'
1449 @echo ' 2: warnings which occur quite often but may still be relevant'
1450 @echo ' 3: more obscure warnings, can most likely be ignored'
1451 @echo ' Multiple levels can be combined with W=12 or W=123'
1453 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1454 @echo 'For further info see the ./README file'
1457 help-board-dirs := $(addprefix help-,$(board-dirs))
1459 help-boards: $(help-board-dirs)
1461 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1463 $(help-board-dirs): help-%:
1464 @echo 'Architecture specific targets ($(SRCARCH) $*):'
1465 @$(if $(boards-per-dir), \
1466 $(foreach b, $(boards-per-dir), \
1467 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1471 # Documentation targets
1472 # ---------------------------------------------------------------------------
1473 DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1474 linkcheckdocs dochelp refcheckdocs
1475 PHONY += $(DOC_TARGETS)
1476 $(DOC_TARGETS): scripts_basic FORCE
1477 $(Q)$(MAKE) $(build)=Documentation $@
1479 else # KBUILD_EXTMOD
1482 # External module support.
1483 # When building external modules the kernel used as basis is considered
1484 # read-only, and no consistency checks are made and the make
1485 # system is not used on the basis kernel. If updates are required
1486 # in the basis kernel ordinary make commands (without M=...) must
1489 # The following are the only valid targets when building external
1491 # make M=dir clean Delete all automatically generated files
1492 # make M=dir modules Make all modules in specified dir
1493 # make M=dir Same as 'make M=dir modules'
1494 # make M=dir modules_install
1495 # Install the modules built in the module directory
1496 # Assumes install directory is already created
1498 # We are always building modules
1500 PHONY += crmodverdir
1504 PHONY += $(objtree)/Module.symvers
1505 $(objtree)/Module.symvers:
1506 @test -e $(objtree)/Module.symvers || ( \
1508 echo " WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1509 echo " is missing; modules will have no dependencies and modversions."; \
1512 module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
1513 PHONY += $(module-dirs) modules
1514 $(module-dirs): crmodverdir $(objtree)/Module.symvers
1515 $(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@)
1517 modules: $(module-dirs)
1518 @$(kecho) ' Building modules, stage 2.';
1519 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1521 PHONY += modules_install
1522 modules_install: _emodinst_ _emodinst_post
1524 install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1527 $(Q)mkdir -p $(MODLIB)/$(install-dir)
1528 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1530 PHONY += _emodinst_post
1531 _emodinst_post: _emodinst_
1534 clean-dirs := $(addprefix _clean_,$(KBUILD_EXTMOD))
1536 PHONY += $(clean-dirs) clean
1538 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1540 clean: rm-dirs := $(MODVERDIR)
1541 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers
1545 @echo ' Building external modules.'
1546 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1548 @echo ' modules - default target, build the module(s)'
1549 @echo ' modules_install - install the module'
1550 @echo ' clean - remove generated files in module directory only'
1554 PHONY += prepare scripts
1557 endif # KBUILD_EXTMOD
1559 clean: $(clean-dirs)
1562 @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1563 \( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1564 -o -name '*.ko.*' -o -name '*.dtb' -o -name '*.dtb.S' \
1565 -o -name '*.dwo' -o -name '*.lst' \
1567 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1568 -o -name '*.lex.c' -o -name '*.tab.[ch]' \
1569 -o -name '*.asn1.[ch]' \
1570 -o -name '*.symtypes' -o -name 'modules.order' \
1571 -o -name modules.builtin -o -name '.tmp_*.o.*' \
1572 -o -name '*.c.[012]*.*' \
1574 -o -name '*.gcno' \) -type f -print | xargs rm -f
1576 # Generate tags for editors
1577 # ---------------------------------------------------------------------------
1578 quiet_cmd_tags = GEN $@
1579 cmd_tags = $(CONFIG_SHELL) $(srctree)/scripts/tags.sh $@
1581 tags TAGS cscope gtags: FORCE
1584 # Scripts to check various things for consistency
1585 # ---------------------------------------------------------------------------
1587 PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1590 find $(srctree)/* $(RCS_FIND_IGNORE) \
1591 -name '*.[hcS]' -type f -print | sort \
1592 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1595 find $(srctree)/* $(RCS_FIND_IGNORE) \
1596 -name '*.[hcS]' -type f -print | sort \
1597 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1600 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/$@
1603 $(PERL) $(srctree)/scripts/namespace.pl
1606 $(PERL) $(srctree)/scripts/export_report.pl
1608 endif #ifeq ($(config-targets),1)
1609 endif #ifeq ($(mixed-targets),1)
1611 PHONY += checkstack kernelrelease kernelversion image_name
1613 # UML needs a little special treatment here. It wants to use the host
1614 # toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
1615 # else wants $(ARCH), including people doing cross-builds, which means
1616 # that $(SUBARCH) doesn't work here.
1618 CHECKSTACK_ARCH := $(SUBARCH)
1620 CHECKSTACK_ARCH := $(ARCH)
1623 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1624 $(PERL) $(src)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1627 @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1630 @echo $(KERNELVERSION)
1633 @echo $(KBUILD_IMAGE)
1635 # Clear a bunch of variables before executing the submake
1637 $(Q)mkdir -p $(objtree)/tools
1638 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(src)/tools/
1641 $(Q)mkdir -p $(objtree)/tools
1642 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(src)/tools/ $*
1645 # ---------------------------------------------------------------------------
1646 # Single targets are compatible with:
1647 # - build with mixed source and output
1648 # - build with separate output dir 'make O=...'
1649 # - external modules
1651 # target-dir => where to store outputfile
1652 # build-dir => directory in kernel source tree to use
1654 ifeq ($(KBUILD_EXTMOD),)
1655 build-dir = $(patsubst %/,%,$(dir $@))
1656 target-dir = $(dir $@)
1658 zap-slash=$(filter-out .,$(patsubst %/,%,$(dir $@)))
1659 build-dir = $(KBUILD_EXTMOD)$(if $(zap-slash),/$(zap-slash))
1660 target-dir = $(if $(KBUILD_EXTMOD),$(dir $<),$(dir $@))
1663 %.s: %.c prepare scripts FORCE
1664 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1665 %.i: %.c prepare scripts FORCE
1666 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1667 %.o: %.c prepare scripts FORCE
1668 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1669 %.lst: %.c prepare scripts FORCE
1670 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1671 %.s: %.S prepare scripts FORCE
1672 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1673 %.o: %.S prepare scripts FORCE
1674 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1675 %.symtypes: %.c prepare scripts FORCE
1676 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1677 %.ll: %.c prepare scripts FORCE
1678 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1681 /: prepare scripts FORCE
1683 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1684 $(build)=$(build-dir)
1685 # Make sure the latest headers are built for Documentation
1686 Documentation/ samples/: headers_install
1687 %/: prepare scripts FORCE
1689 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1690 $(build)=$(build-dir)
1691 %.ko: prepare scripts FORCE
1693 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1694 $(build)=$(build-dir) $(@:.ko=.o)
1695 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1697 # FIXME Should go into a make.lib or something
1698 # ===========================================================================
1700 quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN $(wildcard $(rm-dirs)))
1701 cmd_rmdirs = rm -rf $(rm-dirs)
1703 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
1704 cmd_rmfiles = rm -f $(rm-files)
1706 # Run depmod only if we have System.map and depmod is executable
1707 quiet_cmd_depmod = DEPMOD $(KERNELRELEASE)
1708 cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1711 # Create temporary dir for module support files
1712 # clean it up only when building all modules
1713 cmd_crmodverdir = $(Q)mkdir -p $(MODVERDIR) \
1714 $(if $(KBUILD_MODULES),; rm -f $(MODVERDIR)/*)
1716 # read all saved command lines
1718 cmd_files := $(wildcard .*.cmd $(foreach f,$(sort $(targets)),$(dir $(f)).$(notdir $(f)).cmd))
1720 ifneq ($(cmd_files),)
1721 $(cmd_files): ; # Do not try to update included dependency files
1722 include $(cmd_files)
1725 endif # skip-makefile
1730 # Declare the contents of the PHONY variable as phony. We keep that
1731 # information in a variable so we can use it in if_changed and friends.