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.o 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 no-dot-config-targets := clean mrproper distclean \
224 cscope gtags TAGS tags help% %docs check% coccicheck \
225 $(version_h) headers_% archheaders archscripts \
226 kernelversion %src-pkg
232 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
233 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
238 ifeq ($(KBUILD_EXTMOD),)
239 ifneq ($(filter config %config,$(MAKECMDGOALS)),)
241 ifneq ($(words $(MAKECMDGOALS)),1)
246 # install and modules_install need also be processed one by one
247 ifneq ($(filter install,$(MAKECMDGOALS)),)
248 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
253 ifeq ($(mixed-targets),1)
254 # ===========================================================================
255 # We're called with mixed targets (*config and build targets).
256 # Handle them one by one.
258 PHONY += $(MAKECMDGOALS) __build_one_by_one
260 $(filter-out __build_one_by_one, $(MAKECMDGOALS)): __build_one_by_one
265 for i in $(MAKECMDGOALS); do \
266 $(MAKE) -f $(srctree)/Makefile $$i; \
271 # We need some generic definitions (do not try to remake the file).
272 scripts/Kbuild.include: ;
273 include scripts/Kbuild.include
275 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
276 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
277 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
278 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
280 # SUBARCH tells the usermode build what the underlying arch is. That is set
281 # first, and if a usermode build is happening, the "ARCH=um" on the command
282 # line overrides the setting of ARCH below. If a native build is happening,
283 # then ARCH is assigned, getting whatever value it gets normally, and
284 # SUBARCH is subsequently ignored.
286 SUBARCH := $(shell uname -m | sed -e s/i.86/x86/ -e s/x86_64/x86/ \
287 -e s/sun4u/sparc64/ \
288 -e s/arm.*/arm/ -e s/sa110/arm/ \
289 -e s/s390x/s390/ -e s/parisc64/parisc/ \
290 -e s/ppc.*/powerpc/ -e s/mips.*/mips/ \
291 -e s/sh[234].*/sh/ -e s/aarch64.*/arm64/ \
294 # Cross compiling and selecting different set of gcc/bin-utils
295 # ---------------------------------------------------------------------------
297 # When performing cross compilation for other architectures ARCH shall be set
298 # to the target architecture. (See arch/* for the possibilities).
299 # ARCH can be set during invocation of make:
301 # Another way is to have ARCH set in the environment.
302 # The default ARCH is the host where make is executed.
304 # CROSS_COMPILE specify the prefix used for all executables used
305 # during compilation. Only gcc and related bin-utils executables
306 # are prefixed with $(CROSS_COMPILE).
307 # CROSS_COMPILE can be set on the command line
308 # make CROSS_COMPILE=ia64-linux-
309 # Alternatively CROSS_COMPILE can be set in the environment.
310 # A third alternative is to store a setting in .config so that plain
311 # "make" in the configured kernel build directory always uses that.
312 # Default value for CROSS_COMPILE is not to prefix executables
313 # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
315 CROSS_COMPILE ?= $(CONFIG_CROSS_COMPILE:"%"=%)
317 # Architecture as present in compile.h
318 UTS_MACHINE := $(ARCH)
321 # Additional ARCH settings for x86
325 ifeq ($(ARCH),x86_64)
329 # Additional ARCH settings for sparc
330 ifeq ($(ARCH),sparc32)
333 ifeq ($(ARCH),sparc64)
337 # Additional ARCH settings for sh
342 # Additional ARCH settings for tile
343 ifeq ($(ARCH),tilepro)
346 ifeq ($(ARCH),tilegx)
350 KCONFIG_CONFIG ?= .config
351 export KCONFIG_CONFIG
353 # SHELL used by kbuild
354 CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
355 else if [ -x /bin/bash ]; then echo /bin/bash; \
356 else echo sh; fi ; fi)
358 HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS)
359 HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS)
360 HOST_LFS_LIBS := $(shell getconf LFS_LIBS)
364 HOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 \
365 -fomit-frame-pointer -std=gnu89 $(HOST_LFS_CFLAGS)
366 HOSTCXXFLAGS := -O2 $(HOST_LFS_CFLAGS)
367 HOSTLDFLAGS := $(HOST_LFS_LDFLAGS)
368 HOST_LOADLIBES := $(HOST_LFS_LIBS)
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
390 CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
391 -Wbitwise -Wno-return-void $(CF)
400 # Use USERINCLUDE when you must reference the UAPI directories only.
402 -I$(srctree)/arch/$(SRCARCH)/include/uapi \
403 -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
404 -I$(srctree)/include/uapi \
405 -I$(objtree)/include/generated/uapi \
406 -include $(srctree)/include/linux/kconfig.h
408 # Use LINUXINCLUDE when you must reference the include/ directory.
409 # Needed to be compatible with the O= option
411 -I$(srctree)/arch/$(SRCARCH)/include \
412 -I$(objtree)/arch/$(SRCARCH)/include/generated \
413 $(if $(KBUILD_SRC), -I$(srctree)/include) \
414 -I$(objtree)/include \
417 KBUILD_AFLAGS := -D__ASSEMBLY__
418 KBUILD_CFLAGS := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
419 -fno-strict-aliasing -fno-common -fshort-wchar \
420 -Werror-implicit-function-declaration \
421 -Wno-format-security \
423 KBUILD_CPPFLAGS := -D__KERNEL__
424 KBUILD_AFLAGS_KERNEL :=
425 KBUILD_CFLAGS_KERNEL :=
426 KBUILD_AFLAGS_MODULE := -DMODULE
427 KBUILD_CFLAGS_MODULE := -DMODULE
428 KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
429 GCC_PLUGINS_CFLAGS :=
431 export ARCH SRCARCH CONFIG_SHELL HOSTCC HOSTCFLAGS CROSS_COMPILE AS LD CC
432 export CPP AR NM STRIP OBJCOPY OBJDUMP HOSTLDFLAGS HOST_LOADLIBES
433 export MAKE LEX YACC AWK GENKSYMS INSTALLKERNEL PERL PYTHON UTS_MACHINE
434 export HOSTCXX HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
436 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS LDFLAGS
437 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
438 export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN
439 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
440 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
441 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
442 export KBUILD_ARFLAGS
444 # When compiling out-of-tree modules, put MODVERDIR in the module
445 # tree rather than in the kernel tree. The kernel tree might
447 export MODVERDIR := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_versions
449 # Files to ignore in find ... statements
451 export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o \
452 -name CVS -o -name .pc -o -name .hg -o -name .git \) \
454 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
455 --exclude CVS --exclude .pc --exclude .hg --exclude .git
457 # ===========================================================================
458 # Rules shared between *config targets and build targets
460 # Basic helpers built in scripts/basic/
461 PHONY += scripts_basic
463 $(Q)$(MAKE) $(build)=scripts/basic
464 $(Q)rm -f .tmp_quiet_recordmcount
466 # To avoid any implicit rule to kick in, define an empty command.
467 scripts/basic/%: scripts_basic ;
469 PHONY += outputmakefile
470 # outputmakefile generates a Makefile in the output directory, if using a
471 # separate output directory. This allows convenient use of make in the
474 ifneq ($(KBUILD_SRC),)
475 $(Q)ln -fsn $(srctree) source
476 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile \
477 $(srctree) $(objtree) $(VERSION) $(PATCHLEVEL)
480 ifeq ($(cc-name),clang)
481 ifneq ($(CROSS_COMPILE),)
482 CLANG_TARGET := --target=$(notdir $(CROSS_COMPILE:%-=%))
483 GCC_TOOLCHAIN := $(realpath $(dir $(shell which $(LD)))/..)
485 ifneq ($(GCC_TOOLCHAIN),)
486 CLANG_GCC_TC := --gcc-toolchain=$(GCC_TOOLCHAIN)
488 KBUILD_CFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC)
489 KBUILD_AFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC)
492 ifeq ($(config-targets),1)
493 # ===========================================================================
494 # *config targets only - make sure prerequisites are updated, and descend
495 # in scripts/kconfig to make the *config target
497 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
498 # KBUILD_DEFCONFIG may point out an alternative default configuration
499 # used for 'make defconfig'
500 include arch/$(SRCARCH)/Makefile
501 export KBUILD_DEFCONFIG KBUILD_KCONFIG
503 config: scripts_basic outputmakefile FORCE
504 $(Q)$(MAKE) $(build)=scripts/kconfig $@
506 %config: scripts_basic outputmakefile FORCE
507 $(Q)$(MAKE) $(build)=scripts/kconfig $@
510 # ===========================================================================
511 # Build targets only - this includes vmlinux, arch specific targets, clean
512 # targets and others. In general all targets except *config targets.
514 # If building an external module we do not care about the all: rule
515 # but instead _all depend on modules
517 ifeq ($(KBUILD_EXTMOD),)
523 # Decide whether to build built-in, modular, or both.
524 # Normally, just do built-in.
529 # If we have only "make modules", don't compile built-in objects.
530 # When we're building modules with modversions, we need to consider
531 # the built-in objects during the descend as well, in order to
532 # make sure the checksums are up to date before we record them.
534 ifeq ($(MAKECMDGOALS),modules)
535 KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
538 # If we have "make <whatever> modules", compile modules
539 # in addition to whatever we do anyway.
540 # Just "make" or "make all" shall build modules as well
542 ifneq ($(filter all _all modules,$(MAKECMDGOALS)),)
546 ifeq ($(MAKECMDGOALS),)
550 export KBUILD_MODULES KBUILD_BUILTIN
552 ifeq ($(KBUILD_EXTMOD),)
553 # Additional helpers built in scripts/
554 # Carefully list dependencies so we do not try to build scripts twice
557 scripts: scripts_basic include/config/auto.conf include/config/tristate.conf \
558 asm-generic gcc-plugins
559 $(Q)$(MAKE) $(build)=$(@)
561 # Objects we will link into vmlinux / subdirs we need to visit
563 drivers-y := drivers/ sound/ firmware/
568 endif # KBUILD_EXTMOD
570 ifeq ($(dot-config),1)
572 -include include/config/auto.conf
574 ifeq ($(KBUILD_EXTMOD),)
575 # Read in dependencies to all Kconfig* files, make sure to run
576 # oldconfig if changes are detected.
577 -include include/config/auto.conf.cmd
579 # To avoid any implicit rule to kick in, define an empty command
580 $(KCONFIG_CONFIG) include/config/auto.conf.cmd: ;
582 # If .config is newer than include/config/auto.conf, someone tinkered
583 # with it and forgot to run make oldconfig.
584 # if auto.conf.cmd is missing then we are probably in a cleaned tree so
585 # we execute the config step to be sure to catch updated Kconfig files
586 include/config/%.conf: $(KCONFIG_CONFIG) include/config/auto.conf.cmd
587 $(Q)$(MAKE) -f $(srctree)/Makefile silentoldconfig
589 # external modules needs include/generated/autoconf.h and include/config/auto.conf
590 # but do not care if they are up-to-date. Use auto.conf to trigger the test
591 PHONY += include/config/auto.conf
593 include/config/auto.conf:
594 $(Q)test -e include/generated/autoconf.h -a -e $@ || ( \
596 echo >&2 " ERROR: Kernel configuration is invalid."; \
597 echo >&2 " include/generated/autoconf.h or $@ are missing.";\
598 echo >&2 " Run 'make oldconfig && make prepare' on kernel src to fix it."; \
602 endif # KBUILD_EXTMOD
605 # Dummy target needed, because used as prerequisite
606 include/config/auto.conf: ;
607 endif # $(dot-config)
609 # For the kernel to actually contain only the needed exported symbols,
610 # we have to build modules as well to determine what those symbols are.
611 # (this can be evaluated only once include/config/auto.conf has been included)
612 ifdef CONFIG_TRIM_UNUSED_KSYMS
616 # The all: target is the default when no target is given on the
618 # This allow a user to issue only 'make' to build a kernel including modules
619 # Defaults to vmlinux, but the arch makefile usually adds further targets
622 KBUILD_CFLAGS += $(call cc-option,-fno-PIE)
623 KBUILD_AFLAGS += $(call cc-option,-fno-PIE)
624 CFLAGS_GCOV := -fprofile-arcs -ftest-coverage -fno-tree-loop-im $(call cc-disable-warning,maybe-uninitialized,)
625 export CFLAGS_GCOV CFLAGS_KCOV
627 # The arch Makefile can set ARCH_{CPP,A,C}FLAGS to override the default
628 # values of the respective KBUILD_* variables
632 include arch/$(SRCARCH)/Makefile
634 KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,)
635 KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,)
636 KBUILD_CFLAGS += $(call cc-disable-warning, format-truncation)
637 KBUILD_CFLAGS += $(call cc-disable-warning, format-overflow)
638 KBUILD_CFLAGS += $(call cc-disable-warning, int-in-bool-context)
640 ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
641 KBUILD_CFLAGS += $(call cc-option,-Oz,-Os)
642 KBUILD_CFLAGS += $(call cc-disable-warning,maybe-uninitialized,)
644 ifdef CONFIG_PROFILE_ALL_BRANCHES
645 KBUILD_CFLAGS += -O2 $(call cc-disable-warning,maybe-uninitialized,)
651 KBUILD_CFLAGS += $(call cc-ifversion, -lt, 0409, \
652 $(call cc-disable-warning,maybe-uninitialized,))
654 # Tell gcc to never replace conditional load with a non-conditional one
655 KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
657 # check for 'asm goto'
658 ifeq ($(call shell-cached,$(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC) $(KBUILD_CFLAGS)), y)
659 KBUILD_CFLAGS += -DCC_HAVE_ASM_GOTO
660 KBUILD_AFLAGS += -DCC_HAVE_ASM_GOTO
663 include scripts/Makefile.kcov
664 include scripts/Makefile.gcc-plugins
666 ifdef CONFIG_READABLE_ASM
667 # Disable optimizations that make assembler listings hard to read.
668 # reorder blocks reorders the control in the function
669 # ipa clone creates specialized cloned functions
670 # partial inlining inlines only parts of functions
671 KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
672 $(call cc-option,-fno-ipa-cp-clone,) \
673 $(call cc-option,-fno-partial-inlining)
676 ifneq ($(CONFIG_FRAME_WARN),0)
677 KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
680 # This selects the stack protector compiler flag. Testing it is delayed
681 # until after .config has been reprocessed, in the prepare-compiler-check
683 ifdef CONFIG_CC_STACKPROTECTOR_REGULAR
684 stackp-flag := -fstack-protector
685 stackp-name := REGULAR
687 ifdef CONFIG_CC_STACKPROTECTOR_STRONG
688 stackp-flag := -fstack-protector-strong
689 stackp-name := STRONG
691 # Force off for distro compilers that enable stack protector by default.
692 stackp-flag := $(call cc-option, -fno-stack-protector)
695 # Find arch-specific stack protector compiler sanity-checking script.
696 ifdef CONFIG_CC_STACKPROTECTOR
697 stackp-path := $(srctree)/scripts/gcc-$(SRCARCH)_$(BITS)-has-stack-protector.sh
698 stackp-check := $(wildcard $(stackp-path))
700 KBUILD_CFLAGS += $(stackp-flag)
702 ifeq ($(cc-name),clang)
703 KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
704 KBUILD_CFLAGS += $(call cc-disable-warning, unused-variable)
705 KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier)
706 KBUILD_CFLAGS += $(call cc-disable-warning, gnu)
707 KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
708 # Quiet clang warning: comparison of unsigned expression < 0 is always false
709 KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare)
710 # CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
711 # source of a reference will be _MergedGlobals and not on of the whitelisted names.
712 # See modpost pattern 2
713 KBUILD_CFLAGS += $(call cc-option, -mno-global-merge,)
714 KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior)
715 KBUILD_CFLAGS += $(call cc-option, -no-integrated-as)
716 KBUILD_AFLAGS += $(call cc-option, -no-integrated-as)
719 # These warnings generated too much noise in a regular build.
720 # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
721 KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
722 KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
725 ifdef CONFIG_FRAME_POINTER
726 KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
728 # Some targets (ARM with Thumb2, for example), can't be built with frame
729 # pointers. For those, we don't have FUNCTION_TRACER automatically
730 # select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
731 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
732 # -fomit-frame-pointer with FUNCTION_TRACER.
733 ifndef CONFIG_FUNCTION_TRACER
734 KBUILD_CFLAGS += -fomit-frame-pointer
738 KBUILD_CFLAGS += $(call cc-option, -fno-var-tracking-assignments)
740 ifdef CONFIG_DEBUG_INFO
741 ifdef CONFIG_DEBUG_INFO_SPLIT
742 KBUILD_CFLAGS += $(call cc-option, -gsplit-dwarf, -g)
746 KBUILD_AFLAGS += -Wa,-gdwarf-2
748 ifdef CONFIG_DEBUG_INFO_DWARF4
749 KBUILD_CFLAGS += $(call cc-option, -gdwarf-4,)
752 ifdef CONFIG_DEBUG_INFO_REDUCED
753 KBUILD_CFLAGS += $(call cc-option, -femit-struct-debug-baseonly) \
754 $(call cc-option,-fno-var-tracking)
757 ifdef CONFIG_FUNCTION_TRACER
758 ifndef CC_FLAGS_FTRACE
759 CC_FLAGS_FTRACE := -pg
761 export CC_FLAGS_FTRACE
762 ifdef CONFIG_HAVE_FENTRY
763 CC_USING_FENTRY := $(call cc-option, -mfentry -DCC_USING_FENTRY)
765 KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_USING_FENTRY)
766 KBUILD_AFLAGS += $(CC_USING_FENTRY)
767 ifdef CONFIG_DYNAMIC_FTRACE
768 ifdef CONFIG_HAVE_C_RECORDMCOUNT
769 BUILD_C_RECORDMCOUNT := y
770 export BUILD_C_RECORDMCOUNT
775 # We trigger additional mismatches with less inlining
776 ifdef CONFIG_DEBUG_SECTION_MISMATCH
777 KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
780 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
781 KBUILD_CFLAGS += $(call cc-option,-ffunction-sections,)
782 KBUILD_CFLAGS += $(call cc-option,-fdata-sections,)
785 # arch Makefile may override CC so keep this after arch Makefile is included
786 NOSTDINC_FLAGS += -nostdinc -isystem $(call shell-cached,$(CC) -print-file-name=include)
787 CHECKFLAGS += $(NOSTDINC_FLAGS)
789 # warn about C99 declaration after statement
790 KBUILD_CFLAGS += $(call cc-option,-Wdeclaration-after-statement,)
792 # disable pointer signed / unsigned warnings in gcc 4.0
793 KBUILD_CFLAGS += $(call cc-disable-warning, pointer-sign)
795 # disable invalid "can't wrap" optimizations for signed / pointers
796 KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow)
798 # Make sure -fstack-check isn't enabled (like gentoo apparently did)
799 KBUILD_CFLAGS += $(call cc-option,-fno-stack-check,)
801 # conserve stack if available
802 KBUILD_CFLAGS += $(call cc-option,-fconserve-stack)
804 # disallow errors like 'EXPORT_GPL(foo);' with missing header
805 KBUILD_CFLAGS += $(call cc-option,-Werror=implicit-int)
807 # require functions to have arguments in prototypes, not empty 'int foo()'
808 KBUILD_CFLAGS += $(call cc-option,-Werror=strict-prototypes)
810 # Prohibit date/time macros, which would make the build non-deterministic
811 KBUILD_CFLAGS += $(call cc-option,-Werror=date-time)
813 # enforce correct pointer usage
814 KBUILD_CFLAGS += $(call cc-option,-Werror=incompatible-pointer-types)
816 # Require designated initializers for all marked structures
817 KBUILD_CFLAGS += $(call cc-option,-Werror=designated-init)
819 # use the deterministic mode of AR if available
820 KBUILD_ARFLAGS := $(call ar-option,D)
822 include scripts/Makefile.kasan
823 include scripts/Makefile.extrawarn
824 include scripts/Makefile.ubsan
826 # Add any arch overrides and user supplied CPPFLAGS, AFLAGS and CFLAGS as the
828 KBUILD_CPPFLAGS += $(ARCH_CPPFLAGS) $(KCPPFLAGS)
829 KBUILD_AFLAGS += $(ARCH_AFLAGS) $(KAFLAGS)
830 KBUILD_CFLAGS += $(ARCH_CFLAGS) $(KCFLAGS)
832 # Use --build-id when available.
833 LDFLAGS_BUILD_ID := $(patsubst -Wl$(comma)%,%,\
834 $(call cc-ldoption, -Wl$(comma)--build-id,))
835 KBUILD_LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID)
836 LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)
838 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
839 LDFLAGS_vmlinux += $(call ld-option, --gc-sections,)
842 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
843 LDFLAGS_vmlinux += $(call ld-option, -X,)
846 # Default kernel image to build when no specific target is given.
847 # KBUILD_IMAGE may be overruled on the command line or
848 # set in the environment
849 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
851 export KBUILD_IMAGE ?= vmlinux
854 # INSTALL_PATH specifies where to place the updated kernel and system map
855 # images. Default is /boot, but you can set it to other values
856 export INSTALL_PATH ?= /boot
859 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
860 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
861 # an argument if needed. Otherwise it defaults to the kernel install path
863 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
866 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
867 # relocations required by build roots. This is not defined in the
868 # makefile but the argument can be passed to make if needed.
871 MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
875 # INSTALL_MOD_STRIP, if defined, will cause modules to be
876 # stripped after they are installed. If INSTALL_MOD_STRIP is '1', then
877 # the default option --strip-debug will be used. Otherwise,
878 # INSTALL_MOD_STRIP value will be used as the options to the strip command.
880 ifdef INSTALL_MOD_STRIP
881 ifeq ($(INSTALL_MOD_STRIP),1)
882 mod_strip_cmd = $(STRIP) --strip-debug
884 mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
885 endif # INSTALL_MOD_STRIP=1
888 endif # INSTALL_MOD_STRIP
891 # CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
892 # after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
893 # or CONFIG_MODULE_COMPRESS_XZ.
895 mod_compress_cmd = true
896 ifdef CONFIG_MODULE_COMPRESS
897 ifdef CONFIG_MODULE_COMPRESS_GZIP
898 mod_compress_cmd = gzip -n -f
899 endif # CONFIG_MODULE_COMPRESS_GZIP
900 ifdef CONFIG_MODULE_COMPRESS_XZ
901 mod_compress_cmd = xz -f
902 endif # CONFIG_MODULE_COMPRESS_XZ
903 endif # CONFIG_MODULE_COMPRESS
904 export mod_compress_cmd
906 # Select initial ramdisk compression format, default is gzip(1).
907 # This shall be used by the dracut(8) tool while creating an initramfs image.
909 INITRD_COMPRESS-y := gzip
910 INITRD_COMPRESS-$(CONFIG_RD_BZIP2) := bzip2
911 INITRD_COMPRESS-$(CONFIG_RD_LZMA) := lzma
912 INITRD_COMPRESS-$(CONFIG_RD_XZ) := xz
913 INITRD_COMPRESS-$(CONFIG_RD_LZO) := lzo
914 INITRD_COMPRESS-$(CONFIG_RD_LZ4) := lz4
915 # do not export INITRD_COMPRESS, since we didn't actually
916 # choose a sane default compression above.
917 # export INITRD_COMPRESS := $(INITRD_COMPRESS-y)
919 ifdef CONFIG_MODULE_SIG_ALL
920 $(eval $(call config_filename,MODULE_SIG_KEY))
922 mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
928 ifdef CONFIG_STACK_VALIDATION
929 has_libelf := $(call try-run,\
930 echo "int main() {}" | $(HOSTCC) -xc -o /dev/null -lelf -,1,0)
931 ifeq ($(has_libelf),1)
932 objtool_target := tools/objtool FORCE
934 ifdef CONFIG_UNWINDER_ORC
935 $(error "Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel")
937 $(warning "Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel")
939 SKIP_STACK_VALIDATION := 1
940 export SKIP_STACK_VALIDATION
945 ifeq ($(KBUILD_EXTMOD),)
946 core-y += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
948 vmlinux-dirs := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
949 $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
950 $(net-y) $(net-m) $(libs-y) $(libs-m) $(virt-y)))
952 vmlinux-alldirs := $(sort $(vmlinux-dirs) $(patsubst %/,%,$(filter %/, \
953 $(init-) $(core-) $(drivers-) $(net-) $(libs-) $(virt-))))
955 init-y := $(patsubst %/, %/built-in.o, $(init-y))
956 core-y := $(patsubst %/, %/built-in.o, $(core-y))
957 drivers-y := $(patsubst %/, %/built-in.o, $(drivers-y))
958 net-y := $(patsubst %/, %/built-in.o, $(net-y))
959 libs-y1 := $(patsubst %/, %/lib.a, $(libs-y))
960 libs-y2 := $(filter-out %.a, $(patsubst %/, %/built-in.o, $(libs-y)))
961 virt-y := $(patsubst %/, %/built-in.o, $(virt-y))
963 # Externally visible symbols (used by link-vmlinux.sh)
964 export KBUILD_VMLINUX_INIT := $(head-y) $(init-y)
965 export KBUILD_VMLINUX_MAIN := $(core-y) $(libs-y2) $(drivers-y) $(net-y) $(virt-y)
966 export KBUILD_VMLINUX_LIBS := $(libs-y1)
967 export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
968 export LDFLAGS_vmlinux
969 # used by scripts/package/Makefile
970 export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) arch Documentation include samples scripts tools)
972 vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_INIT) $(KBUILD_VMLINUX_MAIN) $(KBUILD_VMLINUX_LIBS)
974 # Include targets which we want to execute sequentially if the rest of the
975 # kernel build went well. If CONFIG_TRIM_UNUSED_KSYMS is set, this might be
976 # evaluated more than once.
977 PHONY += vmlinux_prereq
978 vmlinux_prereq: $(vmlinux-deps) FORCE
979 ifdef CONFIG_HEADERS_CHECK
980 $(Q)$(MAKE) -f $(srctree)/Makefile headers_check
982 ifdef CONFIG_GDB_SCRIPTS
983 $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
985 ifdef CONFIG_TRIM_UNUSED_KSYMS
986 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
987 "$(MAKE) -f $(srctree)/Makefile vmlinux"
990 # standalone target for easier testing
991 include/generated/autoksyms.h: FORCE
992 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh true
994 ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
996 # Final link of vmlinux with optional arch pass after final link
998 $(CONFIG_SHELL) $< $(LD) $(LDFLAGS) $(LDFLAGS_vmlinux) ; \
999 $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1001 vmlinux: scripts/link-vmlinux.sh vmlinux_prereq $(vmlinux-deps) FORCE
1002 +$(call if_changed,link-vmlinux)
1004 # Build samples along the rest of the kernel
1005 ifdef CONFIG_SAMPLES
1006 vmlinux-dirs += samples
1009 # The actual objects are generated when descending,
1010 # make sure no implicit rule kicks in
1011 $(sort $(vmlinux-deps)): $(vmlinux-dirs) ;
1013 # Handle descending into subdirectories listed in $(vmlinux-dirs)
1014 # Preset locale variables to speed up the build process. Limit locale
1015 # tweaks to this spot to avoid wrong language settings when running
1016 # make menuconfig etc.
1017 # Error messages still appears in the original language
1019 PHONY += $(vmlinux-dirs)
1020 $(vmlinux-dirs): prepare scripts
1021 $(Q)$(MAKE) $(build)=$@ need-builtin=1
1023 define filechk_kernel.release
1024 echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1027 # Store (new) KERNELRELEASE string in include/config/kernel.release
1028 include/config/kernel.release: include/config/auto.conf FORCE
1029 $(call filechk,kernel.release)
1032 # Things we need to do before we recursively start building the kernel
1033 # or the modules are listed in "prepare".
1034 # A multi level approach is used. prepareN is processed before prepareN-1.
1035 # archprepare is used in arch Makefiles and when processed asm symlink,
1036 # version.h and scripts_basic is processed / created.
1038 # Listed in dependency order
1039 PHONY += prepare archprepare prepare0 prepare1 prepare2 prepare3
1041 # prepare3 is used to check if we are building in a separate output directory,
1043 # 1) Check that make has not been executed in the kernel src $(srctree)
1044 prepare3: include/config/kernel.release
1045 ifneq ($(KBUILD_SRC),)
1046 @$(kecho) ' Using $(srctree) as source for kernel'
1047 $(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \
1048 echo >&2 " $(srctree) is not clean, please run 'make mrproper'"; \
1049 echo >&2 " in the '$(srctree)' directory.";\
1054 # prepare2 creates a makefile if using a separate output directory.
1055 # From this point forward, .config has been reprocessed, so any rules
1056 # that need to depend on updated CONFIG_* values can be checked here.
1057 prepare2: prepare3 prepare-compiler-check outputmakefile asm-generic
1059 prepare1: prepare2 $(version_h) include/generated/utsrelease.h \
1060 include/config/auto.conf
1063 archprepare: archheaders archscripts prepare1 scripts_basic
1065 prepare0: archprepare gcc-plugins
1066 $(Q)$(MAKE) $(build)=.
1068 # All the preparing..
1069 prepare: prepare0 prepare-objtool
1071 # Support for using generic headers in asm-generic
1072 PHONY += asm-generic uapi-asm-generic
1073 asm-generic: uapi-asm-generic
1074 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
1075 src=asm obj=arch/$(SRCARCH)/include/generated/asm
1077 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
1078 src=uapi/asm obj=arch/$(SRCARCH)/include/generated/uapi/asm
1080 PHONY += prepare-objtool
1081 prepare-objtool: $(objtool_target)
1083 # Check for CONFIG flags that require compiler support. Abort the build
1084 # after .config has been processed, but before the kernel build starts.
1086 # For security-sensitive CONFIG options, we don't want to fallback and/or
1087 # silently change which compiler flags will be used, since that leads to
1088 # producing kernels with different security feature characteristics
1089 # depending on the compiler used. (For example, "But I selected
1090 # CC_STACKPROTECTOR_STRONG! Why did it build with _REGULAR?!")
1091 PHONY += prepare-compiler-check
1092 prepare-compiler-check: FORCE
1093 # Make sure compiler supports requested stack protector flag.
1095 ifeq ($(call cc-option, $(stackp-flag)),)
1096 @echo Cannot use CONFIG_CC_STACKPROTECTOR_$(stackp-name): \
1097 $(stackp-flag) not supported by compiler >&2 && exit 1
1100 # Make sure compiler does not have buggy stack-protector support.
1102 ifneq ($(shell $(CONFIG_SHELL) $(stackp-check) $(CC) $(KBUILD_CPPFLAGS) $(biarch)),y)
1103 @echo Cannot use CONFIG_CC_STACKPROTECTOR_$(stackp-name): \
1104 $(stackp-flag) available but compiler is broken >&2 && exit 1
1109 # Generate some files
1110 # ---------------------------------------------------------------------------
1112 # KERNELRELEASE can change from a few different places, meaning version.h
1113 # needs to be updated, so this check is forced on all builds
1116 define filechk_utsrelease.h
1117 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1118 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1121 (echo \#define UTS_RELEASE \"$(KERNELRELEASE)\";)
1124 define filechk_version.h
1125 (echo \#define LINUX_VERSION_CODE $(shell \
1126 expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1127 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))';)
1130 $(version_h): $(srctree)/Makefile FORCE
1131 $(call filechk,version.h)
1132 $(Q)rm -f $(old_version_h)
1134 include/generated/utsrelease.h: include/config/kernel.release FORCE
1135 $(call filechk,utsrelease.h)
1139 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1140 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1142 # ---------------------------------------------------------------------------
1145 #Default location for installed headers
1146 export INSTALL_HDR_PATH = $(objtree)/usr
1148 # If we do an all arch process set dst to include/arch-$(SRCARCH)
1149 hdr-dst = $(if $(KBUILD_HEADERS), dst=include/arch-$(SRCARCH), dst=include)
1151 PHONY += archheaders
1154 PHONY += archscripts
1158 __headers: $(version_h) scripts_basic uapi-asm-generic archheaders archscripts
1159 $(Q)$(MAKE) $(build)=scripts build_unifdef
1161 PHONY += headers_install_all
1162 headers_install_all:
1163 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh install
1165 PHONY += headers_install
1166 headers_install: __headers
1167 $(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1168 $(error Headers not exportable for the $(SRCARCH) architecture))
1169 $(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include
1170 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi $(hdr-dst)
1172 PHONY += headers_check_all
1173 headers_check_all: headers_install_all
1174 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh check
1176 PHONY += headers_check
1177 headers_check: headers_install
1178 $(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include HDRCHECK=1
1179 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi $(hdr-dst) HDRCHECK=1
1181 # ---------------------------------------------------------------------------
1186 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1188 PHONY += kselftest-clean
1190 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests clean
1192 PHONY += kselftest-merge
1194 $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1195 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/kconfig/merge_config.sh \
1196 -m $(objtree)/.config \
1197 $(srctree)/tools/testing/selftests/*/config
1198 +$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1200 # ---------------------------------------------------------------------------
1203 ifdef CONFIG_MODULES
1205 # By default, build modules as well
1211 # A module can be listed more than once in obj-m resulting in
1212 # duplicate lines in modules.order files. Those are removed
1213 # using awk while concatenating to the final file.
1216 modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux) modules.builtin
1217 $(Q)$(AWK) '!x[$$0]++' $(vmlinux-dirs:%=$(objtree)/%/modules.order) > $(objtree)/modules.order
1218 @$(kecho) ' Building modules, stage 2.';
1219 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1221 modules.builtin: $(vmlinux-dirs:%=%/modules.builtin)
1222 $(Q)$(AWK) '!x[$$0]++' $^ > $(objtree)/modules.builtin
1224 %/modules.builtin: include/config/auto.conf
1225 $(Q)$(MAKE) $(modbuiltin)=$*
1228 # Target to prepare building external modules
1229 PHONY += modules_prepare
1230 modules_prepare: prepare scripts
1232 # Target to install modules
1233 PHONY += modules_install
1234 modules_install: _modinst_ _modinst_post
1238 @rm -rf $(MODLIB)/kernel
1239 @rm -f $(MODLIB)/source
1240 @mkdir -p $(MODLIB)/kernel
1241 @ln -s $(abspath $(srctree)) $(MODLIB)/source
1242 @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
1243 rm -f $(MODLIB)/build ; \
1244 ln -s $(CURDIR) $(MODLIB)/build ; \
1246 @cp -f $(objtree)/modules.order $(MODLIB)/
1247 @cp -f $(objtree)/modules.builtin $(MODLIB)/
1248 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1250 # This depmod is only for convenience to give the initial
1251 # boot a modules.dep even before / is mounted read-write. However the
1252 # boot script depmod is the master version.
1253 PHONY += _modinst_post
1254 _modinst_post: _modinst_
1257 ifeq ($(CONFIG_MODULE_SIG), y)
1258 PHONY += modules_sign
1260 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1263 else # CONFIG_MODULES
1265 # Modules not configured
1266 # ---------------------------------------------------------------------------
1268 PHONY += modules modules_install
1269 modules modules_install:
1271 @echo >&2 "The present kernel configuration has modules disabled."
1272 @echo >&2 "Type 'make config' and enable loadable module support."
1273 @echo >&2 "Then build a kernel with module support enabled."
1277 endif # CONFIG_MODULES
1280 # Cleaning is done on three levels.
1281 # make clean Delete most generated files
1282 # Leave enough to build external modules
1283 # make mrproper Delete the current configuration, and all generated files
1284 # make distclean Remove editor backup files, patch leftover files and the like
1286 # Directories & files removed with 'make clean'
1287 CLEAN_DIRS += $(MODVERDIR)
1289 # Directories & files removed with 'make mrproper'
1290 MRPROPER_DIRS += include/config usr/include include/generated \
1291 arch/*/include/generated .tmp_objdiff
1292 MRPROPER_FILES += .config .config.old .version \
1293 Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS \
1294 signing_key.pem signing_key.priv signing_key.x509 \
1295 x509.genkey extra_certificates signing_key.x509.keyid \
1296 signing_key.x509.signer vmlinux-gdb.py
1298 # clean - Delete most, but leave enough to build external modules
1300 clean: rm-dirs := $(CLEAN_DIRS)
1301 clean: rm-files := $(CLEAN_FILES)
1302 clean-dirs := $(addprefix _clean_, . $(vmlinux-alldirs) Documentation samples)
1304 PHONY += $(clean-dirs) clean archclean vmlinuxclean
1306 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1309 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1310 $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1312 clean: archclean vmlinuxclean
1314 # mrproper - Delete all generated files, including .config
1316 mrproper: rm-dirs := $(wildcard $(MRPROPER_DIRS))
1317 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1318 mrproper-dirs := $(addprefix _mrproper_,scripts)
1320 PHONY += $(mrproper-dirs) mrproper archmrproper
1322 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1324 mrproper: clean archmrproper $(mrproper-dirs)
1333 @find $(srctree) $(RCS_FIND_IGNORE) \
1334 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1335 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1336 -o -name 'core' \) \
1337 -type f -print | xargs rm -f
1340 # Packaging of the kernel to various formats
1341 # ---------------------------------------------------------------------------
1342 # rpm target kept for backward compatibility
1343 package-dir := scripts/package
1346 $(Q)$(MAKE) $(build)=$(package-dir) $@
1347 %pkg: include/config/kernel.release FORCE
1348 $(Q)$(MAKE) $(build)=$(package-dir) $@
1350 @echo " WARNING: \"rpm\" target will be removed after Linux 4.18"
1351 @echo " Please use \"rpm-pkg\" instead."
1354 # Brief documentation of the typical targets used
1355 # ---------------------------------------------------------------------------
1357 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1358 boards := $(sort $(notdir $(boards)))
1359 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1360 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1364 @echo 'Cleaning targets:'
1365 @echo ' clean - Remove most generated files but keep the config and'
1366 @echo ' enough build support to build external modules'
1367 @echo ' mrproper - Remove all generated files + config + various backup files'
1368 @echo ' distclean - mrproper + remove editor backup and patch files'
1370 @echo 'Configuration targets:'
1371 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1373 @echo 'Other generic targets:'
1374 @echo ' all - Build all targets marked with [*]'
1375 @echo '* vmlinux - Build the bare kernel'
1376 @echo '* modules - Build all modules'
1377 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1378 @echo ' dir/ - Build all files in dir and below'
1379 @echo ' dir/file.[ois] - Build specified target only'
1380 @echo ' dir/file.ll - Build the LLVM assembly file'
1381 @echo ' (requires compiler support for LLVM assembly generation)'
1382 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1383 @echo ' (requires a recent binutils and recent build (System.map))'
1384 @echo ' dir/file.ko - Build module including final link'
1385 @echo ' modules_prepare - Set up for building external modules'
1386 @echo ' tags/TAGS - Generate tags file for editors'
1387 @echo ' cscope - Generate cscope index'
1388 @echo ' gtags - Generate GNU GLOBAL index'
1389 @echo ' kernelrelease - Output the release version string (use with make -s)'
1390 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1391 @echo ' image_name - Output the image name (use with make -s)'
1392 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1393 echo ' (default: $(INSTALL_HDR_PATH))'; \
1395 @echo 'Static analysers:'
1396 @echo ' checkstack - Generate a list of stack hogs'
1397 @echo ' namespacecheck - Name space analysis on compiled kernel'
1398 @echo ' versioncheck - Sanity check on version.h usage'
1399 @echo ' includecheck - Check for duplicate included header files'
1400 @echo ' export_report - List the usages of all exported symbols'
1401 @echo ' headers_check - Sanity check on exported headers'
1402 @echo ' headerdep - Detect inclusion cycles in headers'
1403 @echo ' coccicheck - Check with Coccinelle'
1405 @echo 'Kernel selftest:'
1406 @echo ' kselftest - Build and run kernel selftest (run as root)'
1407 @echo ' Build, install, and boot kernel before'
1408 @echo ' running kselftest on it'
1409 @echo ' kselftest-clean - Remove all generated kselftest files'
1410 @echo ' kselftest-merge - Merge all the config dependencies of kselftest to existing'
1413 @echo 'Userspace tools targets:'
1414 @echo ' use "make tools/help"'
1415 @echo ' or "cd tools; make help"'
1417 @echo 'Kernel packaging:'
1418 @$(MAKE) $(build)=$(package-dir) help
1420 @echo 'Documentation targets:'
1421 @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1423 @echo 'Architecture specific targets ($(SRCARCH)):'
1424 @$(if $(archhelp),$(archhelp),\
1425 echo ' No architecture specific help defined for $(SRCARCH)')
1428 $(foreach b, $(boards), \
1429 printf " %-24s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1431 @$(if $(board-dirs), \
1432 $(foreach b, $(board-dirs), \
1433 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1434 printf " %-16s - Show all of the above\\n" help-boards; \
1437 @echo ' make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1438 @echo ' make V=2 [targets] 2 => give reason for rebuild of target'
1439 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1440 @echo ' make C=1 [targets] Check re-compiled c source with $$CHECK (sparse by default)'
1441 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1442 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1443 @echo ' make W=n [targets] Enable extra gcc checks, n=1,2,3 where'
1444 @echo ' 1: warnings which may be relevant and do not occur too often'
1445 @echo ' 2: warnings which occur quite often but may still be relevant'
1446 @echo ' 3: more obscure warnings, can most likely be ignored'
1447 @echo ' Multiple levels can be combined with W=12 or W=123'
1449 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1450 @echo 'For further info see the ./README file'
1453 help-board-dirs := $(addprefix help-,$(board-dirs))
1455 help-boards: $(help-board-dirs)
1457 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1459 $(help-board-dirs): help-%:
1460 @echo 'Architecture specific targets ($(SRCARCH) $*):'
1461 @$(if $(boards-per-dir), \
1462 $(foreach b, $(boards-per-dir), \
1463 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1467 # Documentation targets
1468 # ---------------------------------------------------------------------------
1469 DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1470 linkcheckdocs dochelp refcheckdocs
1471 PHONY += $(DOC_TARGETS)
1472 $(DOC_TARGETS): scripts_basic FORCE
1473 $(Q)$(MAKE) $(build)=Documentation $@
1475 else # KBUILD_EXTMOD
1478 # External module support.
1479 # When building external modules the kernel used as basis is considered
1480 # read-only, and no consistency checks are made and the make
1481 # system is not used on the basis kernel. If updates are required
1482 # in the basis kernel ordinary make commands (without M=...) must
1485 # The following are the only valid targets when building external
1487 # make M=dir clean Delete all automatically generated files
1488 # make M=dir modules Make all modules in specified dir
1489 # make M=dir Same as 'make M=dir modules'
1490 # make M=dir modules_install
1491 # Install the modules built in the module directory
1492 # Assumes install directory is already created
1494 # We are always building modules
1496 PHONY += crmodverdir
1500 PHONY += $(objtree)/Module.symvers
1501 $(objtree)/Module.symvers:
1502 @test -e $(objtree)/Module.symvers || ( \
1504 echo " WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1505 echo " is missing; modules will have no dependencies and modversions."; \
1508 module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
1509 PHONY += $(module-dirs) modules
1510 $(module-dirs): crmodverdir $(objtree)/Module.symvers
1511 $(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@)
1513 modules: $(module-dirs)
1514 @$(kecho) ' Building modules, stage 2.';
1515 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1517 PHONY += modules_install
1518 modules_install: _emodinst_ _emodinst_post
1520 install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1523 $(Q)mkdir -p $(MODLIB)/$(install-dir)
1524 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1526 PHONY += _emodinst_post
1527 _emodinst_post: _emodinst_
1530 clean-dirs := $(addprefix _clean_,$(KBUILD_EXTMOD))
1532 PHONY += $(clean-dirs) clean
1534 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1536 clean: rm-dirs := $(MODVERDIR)
1537 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers
1541 @echo ' Building external modules.'
1542 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1544 @echo ' modules - default target, build the module(s)'
1545 @echo ' modules_install - install the module'
1546 @echo ' clean - remove generated files in module directory only'
1550 PHONY += prepare scripts
1553 endif # KBUILD_EXTMOD
1555 clean: $(clean-dirs)
1558 @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1559 \( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1560 -o -name '*.ko.*' -o -name '*.dtb' -o -name '*.dtb.S' \
1561 -o -name '*.dwo' -o -name '*.lst' \
1563 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1564 -o -name '*.symtypes' -o -name 'modules.order' \
1565 -o -name modules.builtin -o -name '.tmp_*.o.*' \
1566 -o -name .cache.mk \
1567 -o -name '*.c.[012]*.*' \
1569 -o -name '*.gcno' \) -type f -print | xargs rm -f
1571 # Generate tags for editors
1572 # ---------------------------------------------------------------------------
1573 quiet_cmd_tags = GEN $@
1574 cmd_tags = $(CONFIG_SHELL) $(srctree)/scripts/tags.sh $@
1576 tags TAGS cscope gtags: FORCE
1579 # Scripts to check various things for consistency
1580 # ---------------------------------------------------------------------------
1582 PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1585 find $(srctree)/* $(RCS_FIND_IGNORE) \
1586 -name '*.[hcS]' -type f -print | sort \
1587 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1590 find $(srctree)/* $(RCS_FIND_IGNORE) \
1591 -name '*.[hcS]' -type f -print | sort \
1592 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1595 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/$@
1598 $(PERL) $(srctree)/scripts/namespace.pl
1601 $(PERL) $(srctree)/scripts/export_report.pl
1603 endif #ifeq ($(config-targets),1)
1604 endif #ifeq ($(mixed-targets),1)
1606 PHONY += checkstack kernelrelease kernelversion image_name
1608 # UML needs a little special treatment here. It wants to use the host
1609 # toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
1610 # else wants $(ARCH), including people doing cross-builds, which means
1611 # that $(SUBARCH) doesn't work here.
1613 CHECKSTACK_ARCH := $(SUBARCH)
1615 CHECKSTACK_ARCH := $(ARCH)
1618 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1619 $(PERL) $(src)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1622 @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1625 @echo $(KERNELVERSION)
1628 @echo $(KBUILD_IMAGE)
1630 # Clear a bunch of variables before executing the submake
1632 $(Q)mkdir -p $(objtree)/tools
1633 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(src)/tools/
1636 $(Q)mkdir -p $(objtree)/tools
1637 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(src)/tools/ $*
1640 # ---------------------------------------------------------------------------
1641 # Single targets are compatible with:
1642 # - build with mixed source and output
1643 # - build with separate output dir 'make O=...'
1644 # - external modules
1646 # target-dir => where to store outputfile
1647 # build-dir => directory in kernel source tree to use
1649 ifeq ($(KBUILD_EXTMOD),)
1650 build-dir = $(patsubst %/,%,$(dir $@))
1651 target-dir = $(dir $@)
1653 zap-slash=$(filter-out .,$(patsubst %/,%,$(dir $@)))
1654 build-dir = $(KBUILD_EXTMOD)$(if $(zap-slash),/$(zap-slash))
1655 target-dir = $(if $(KBUILD_EXTMOD),$(dir $<),$(dir $@))
1658 %.s: %.c prepare scripts FORCE
1659 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1660 %.i: %.c prepare scripts FORCE
1661 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1662 %.o: %.c prepare scripts FORCE
1663 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1664 %.lst: %.c prepare scripts FORCE
1665 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1666 %.s: %.S prepare scripts FORCE
1667 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1668 %.o: %.S prepare scripts FORCE
1669 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1670 %.symtypes: %.c prepare scripts FORCE
1671 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1672 %.ll: %.c prepare scripts FORCE
1673 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1676 /: prepare scripts FORCE
1678 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1679 $(build)=$(build-dir)
1680 # Make sure the latest headers are built for Documentation
1681 Documentation/ samples/: headers_install
1682 %/: prepare scripts FORCE
1684 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1685 $(build)=$(build-dir)
1686 %.ko: prepare scripts FORCE
1688 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1689 $(build)=$(build-dir) $(@:.ko=.o)
1690 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1692 # FIXME Should go into a make.lib or something
1693 # ===========================================================================
1695 quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN $(wildcard $(rm-dirs)))
1696 cmd_rmdirs = rm -rf $(rm-dirs)
1698 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
1699 cmd_rmfiles = rm -f $(rm-files)
1701 # Run depmod only if we have System.map and depmod is executable
1702 quiet_cmd_depmod = DEPMOD $(KERNELRELEASE)
1703 cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1704 $(KERNELRELEASE) "$(patsubst y,_,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX))"
1706 # Create temporary dir for module support files
1707 # clean it up only when building all modules
1708 cmd_crmodverdir = $(Q)mkdir -p $(MODVERDIR) \
1709 $(if $(KBUILD_MODULES),; rm -f $(MODVERDIR)/*)
1711 # read all saved command lines
1713 cmd_files := $(wildcard .*.cmd $(foreach f,$(sort $(targets)),$(dir $(f)).$(notdir $(f)).cmd))
1715 ifneq ($(cmd_files),)
1716 $(cmd_files): ; # Do not try to update included dependency files
1717 include $(cmd_files)
1720 endif # skip-makefile
1725 # Declare the contents of the .PHONY variable as phony. We keep that
1726 # information in a variable so we can use it in if_changed and friends.