xref: /linux/Makefile (revision 8900d92fd666d936a7bfb4c567ac26736a414fb4)
1# SPDX-License-Identifier: GPL-2.0
2VERSION = 5
3PATCHLEVEL = 12
4SUBLEVEL = 0
5EXTRAVERSION =
6NAME = Frozen Wasteland
7
8# *DOCUMENTATION*
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.
13
14$(if $(filter __%, $(MAKECMDGOALS)), \
15	$(error targets prefixed with '__' are only for internal use))
16
17# That's our default target when none is given on the command line
18PHONY := __all
19__all:
20
21# We are using a recursive build, so we need to do a little thinking
22# to get the ordering right.
23#
24# Most importantly: sub-Makefiles should only ever modify files in
25# their own directory. If in some directory we have a dependency on
26# a file in another dir (which doesn't happen often, but it's often
27# unavoidable when linking the built-in.a targets which finally
28# turn into vmlinux), we will call a sub make in that other dir, and
29# after that we are sure that everything which is in that other dir
30# is now up to date.
31#
32# The only cases where we need to modify files which have global
33# effects are thus separated out and done before the recursive
34# descending is started. They are now explicitly listed as the
35# prepare rule.
36
37ifneq ($(sub_make_done),1)
38
39# Do not use make's built-in rules and variables
40# (this increases performance and avoids hard-to-debug behaviour)
41MAKEFLAGS += -rR
42
43# Avoid funny character set dependencies
44unexport LC_ALL
45LC_COLLATE=C
46LC_NUMERIC=C
47export LC_COLLATE LC_NUMERIC
48
49# Avoid interference with shell env settings
50unexport GREP_OPTIONS
51
52# Beautify output
53# ---------------------------------------------------------------------------
54#
55# Normally, we echo the whole command before executing it. By making
56# that echo $($(quiet)$(cmd)), we now have the possibility to set
57# $(quiet) to choose other forms of output instead, e.g.
58#
59#         quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
60#         cmd_cc_o_c       = $(CC) $(c_flags) -c -o $@ $<
61#
62# If $(quiet) is empty, the whole command will be printed.
63# If it is set to "quiet_", only the short version will be printed.
64# If it is set to "silent_", nothing will be printed at all, since
65# the variable $(silent_cmd_cc_o_c) doesn't exist.
66#
67# A simple variant is to prefix commands with $(Q) - that's useful
68# for commands that shall be hidden in non-verbose mode.
69#
70#	$(Q)ln $@ :<
71#
72# If KBUILD_VERBOSE equals 0 then the above command will be hidden.
73# If KBUILD_VERBOSE equals 1 then the above command is displayed.
74# If KBUILD_VERBOSE equals 2 then give the reason why each target is rebuilt.
75#
76# To put more focus on warnings, be less verbose as default
77# Use 'make V=1' to see the full commands
78
79ifeq ("$(origin V)", "command line")
80  KBUILD_VERBOSE = $(V)
81endif
82ifndef KBUILD_VERBOSE
83  KBUILD_VERBOSE = 0
84endif
85
86ifeq ($(KBUILD_VERBOSE),1)
87  quiet =
88  Q =
89else
90  quiet=quiet_
91  Q = @
92endif
93
94# If the user is running make -s (silent mode), suppress echoing of
95# commands
96
97ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
98  quiet=silent_
99  KBUILD_VERBOSE = 0
100endif
101
102export quiet Q KBUILD_VERBOSE
103
104# Call a source code checker (by default, "sparse") as part of the
105# C compilation.
106#
107# Use 'make C=1' to enable checking of only re-compiled files.
108# Use 'make C=2' to enable checking of *all* source files, regardless
109# of whether they are re-compiled or not.
110#
111# See the file "Documentation/dev-tools/sparse.rst" for more details,
112# including where to get the "sparse" utility.
113
114ifeq ("$(origin C)", "command line")
115  KBUILD_CHECKSRC = $(C)
116endif
117ifndef KBUILD_CHECKSRC
118  KBUILD_CHECKSRC = 0
119endif
120
121export KBUILD_CHECKSRC
122
123# Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
124# directory of external module to build. Setting M= takes precedence.
125ifeq ("$(origin M)", "command line")
126  KBUILD_EXTMOD := $(M)
127endif
128
129$(if $(word 2, $(KBUILD_EXTMOD)), \
130	$(error building multiple external modules is not supported))
131
132export KBUILD_EXTMOD
133
134# Kbuild will save output files in the current working directory.
135# This does not need to match to the root of the kernel source tree.
136#
137# For example, you can do this:
138#
139#  cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
140#
141# If you want to save output files in a different location, there are
142# two syntaxes to specify it.
143#
144# 1) O=
145# Use "make O=dir/to/store/output/files/"
146#
147# 2) Set KBUILD_OUTPUT
148# Set the environment variable KBUILD_OUTPUT to point to the output directory.
149# export KBUILD_OUTPUT=dir/to/store/output/files/; make
150#
151# The O= assignment takes precedence over the KBUILD_OUTPUT environment
152# variable.
153
154# Do we want to change the working directory?
155ifeq ("$(origin O)", "command line")
156  KBUILD_OUTPUT := $(O)
157endif
158
159ifneq ($(KBUILD_OUTPUT),)
160# Make's built-in functions such as $(abspath ...), $(realpath ...) cannot
161# expand a shell special character '~'. We use a somewhat tedious way here.
162abs_objtree := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) && pwd)
163$(if $(abs_objtree),, \
164     $(error failed to create output directory "$(KBUILD_OUTPUT)"))
165
166# $(realpath ...) resolves symlinks
167abs_objtree := $(realpath $(abs_objtree))
168else
169abs_objtree := $(CURDIR)
170endif # ifneq ($(KBUILD_OUTPUT),)
171
172ifeq ($(abs_objtree),$(CURDIR))
173# Suppress "Entering directory ..." unless we are changing the work directory.
174MAKEFLAGS += --no-print-directory
175else
176need-sub-make := 1
177endif
178
179this-makefile := $(lastword $(MAKEFILE_LIST))
180abs_srctree := $(realpath $(dir $(this-makefile)))
181
182ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
183$(error source directory cannot contain spaces or colons)
184endif
185
186ifneq ($(abs_srctree),$(abs_objtree))
187# Look for make include files relative to root of kernel src
188#
189# This does not become effective immediately because MAKEFLAGS is re-parsed
190# once after the Makefile is read. We need to invoke sub-make.
191MAKEFLAGS += --include-dir=$(abs_srctree)
192need-sub-make := 1
193endif
194
195ifneq ($(filter 3.%,$(MAKE_VERSION)),)
196# 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
197# We need to invoke sub-make to avoid implicit rules in the top Makefile.
198need-sub-make := 1
199# Cancel implicit rules for this Makefile.
200$(this-makefile): ;
201endif
202
203export abs_srctree abs_objtree
204export sub_make_done := 1
205
206ifeq ($(need-sub-make),1)
207
208PHONY += $(MAKECMDGOALS) __sub-make
209
210$(filter-out $(this-makefile), $(MAKECMDGOALS)) __all: __sub-make
211	@:
212
213# Invoke a second make in the output directory, passing relevant variables
214__sub-make:
215	$(Q)$(MAKE) -C $(abs_objtree) -f $(abs_srctree)/Makefile $(MAKECMDGOALS)
216
217endif # need-sub-make
218endif # sub_make_done
219
220# We process the rest of the Makefile if this is the final invocation of make
221ifeq ($(need-sub-make),)
222
223# Do not print "Entering directory ...",
224# but we want to display it when entering to the output directory
225# so that IDEs/editors are able to understand relative filenames.
226MAKEFLAGS += --no-print-directory
227
228ifeq ($(abs_srctree),$(abs_objtree))
229        # building in the source tree
230        srctree := .
231	building_out_of_srctree :=
232else
233        ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
234                # building in a subdirectory of the source tree
235                srctree := ..
236        else
237                srctree := $(abs_srctree)
238        endif
239	building_out_of_srctree := 1
240endif
241
242ifneq ($(KBUILD_ABS_SRCTREE),)
243srctree := $(abs_srctree)
244endif
245
246objtree		:= .
247VPATH		:= $(srctree)
248
249export building_out_of_srctree srctree objtree VPATH
250
251# To make sure we do not include .config for any of the *config targets
252# catch them early, and hand them over to scripts/kconfig/Makefile
253# It is allowed to specify more targets when calling make, including
254# mixing *config targets and build targets.
255# For example 'make oldconfig all'.
256# Detect when mixed targets is specified, and make a second invocation
257# of make so .config is not included in this case either (for *config).
258
259version_h := include/generated/uapi/linux/version.h
260
261clean-targets := %clean mrproper cleandocs
262no-dot-config-targets := $(clean-targets) \
263			 cscope gtags TAGS tags help% %docs check% coccicheck \
264			 $(version_h) headers headers_% archheaders archscripts \
265			 %asm-generic kernelversion %src-pkg dt_binding_check \
266			 outputmakefile
267no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease \
268			  image_name
269single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
270
271config-build	:=
272mixed-build	:=
273need-config	:= 1
274may-sync-config	:= 1
275single-build	:=
276
277ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
278	ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
279		need-config :=
280	endif
281endif
282
283ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
284	ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
285		may-sync-config :=
286	endif
287endif
288
289ifneq ($(KBUILD_EXTMOD),)
290	may-sync-config :=
291endif
292
293ifeq ($(KBUILD_EXTMOD),)
294        ifneq ($(filter %config,$(MAKECMDGOALS)),)
295		config-build := 1
296                ifneq ($(words $(MAKECMDGOALS)),1)
297			mixed-build := 1
298                endif
299        endif
300endif
301
302# We cannot build single targets and the others at the same time
303ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
304	single-build := 1
305	ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
306		mixed-build := 1
307	endif
308endif
309
310# For "make -j clean all", "make -j mrproper defconfig all", etc.
311ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
312        ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
313		mixed-build := 1
314        endif
315endif
316
317# install and modules_install need also be processed one by one
318ifneq ($(filter install,$(MAKECMDGOALS)),)
319        ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
320		mixed-build := 1
321        endif
322endif
323
324ifdef mixed-build
325# ===========================================================================
326# We're called with mixed targets (*config and build targets).
327# Handle them one by one.
328
329PHONY += $(MAKECMDGOALS) __build_one_by_one
330
331$(MAKECMDGOALS): __build_one_by_one
332	@:
333
334__build_one_by_one:
335	$(Q)set -e; \
336	for i in $(MAKECMDGOALS); do \
337		$(MAKE) -f $(srctree)/Makefile $$i; \
338	done
339
340else # !mixed-build
341
342include scripts/Kbuild.include
343
344# Read KERNELRELEASE from include/config/kernel.release (if it exists)
345KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
346KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
347export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
348
349include scripts/subarch.include
350
351# Cross compiling and selecting different set of gcc/bin-utils
352# ---------------------------------------------------------------------------
353#
354# When performing cross compilation for other architectures ARCH shall be set
355# to the target architecture. (See arch/* for the possibilities).
356# ARCH can be set during invocation of make:
357# make ARCH=ia64
358# Another way is to have ARCH set in the environment.
359# The default ARCH is the host where make is executed.
360
361# CROSS_COMPILE specify the prefix used for all executables used
362# during compilation. Only gcc and related bin-utils executables
363# are prefixed with $(CROSS_COMPILE).
364# CROSS_COMPILE can be set on the command line
365# make CROSS_COMPILE=ia64-linux-
366# Alternatively CROSS_COMPILE can be set in the environment.
367# Default value for CROSS_COMPILE is not to prefix executables
368# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
369ARCH		?= $(SUBARCH)
370
371# Architecture as present in compile.h
372UTS_MACHINE 	:= $(ARCH)
373SRCARCH 	:= $(ARCH)
374
375# Additional ARCH settings for x86
376ifeq ($(ARCH),i386)
377        SRCARCH := x86
378endif
379ifeq ($(ARCH),x86_64)
380        SRCARCH := x86
381endif
382
383# Additional ARCH settings for sparc
384ifeq ($(ARCH),sparc32)
385       SRCARCH := sparc
386endif
387ifeq ($(ARCH),sparc64)
388       SRCARCH := sparc
389endif
390
391# Additional ARCH settings for sh
392ifeq ($(ARCH),sh64)
393       SRCARCH := sh
394endif
395
396KCONFIG_CONFIG	?= .config
397export KCONFIG_CONFIG
398
399# Default file for 'make defconfig'. This may be overridden by arch-Makefile.
400export KBUILD_DEFCONFIG := defconfig
401
402# SHELL used by kbuild
403CONFIG_SHELL := sh
404
405HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
406HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
407HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
408
409ifneq ($(LLVM),)
410HOSTCC	= clang
411HOSTCXX	= clang++
412else
413HOSTCC	= gcc
414HOSTCXX	= g++
415endif
416
417export KBUILD_USERCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
418			      -O2 -fomit-frame-pointer -std=gnu89
419export KBUILD_USERLDFLAGS :=
420
421KBUILD_HOSTCFLAGS   := $(KBUILD_USERCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
422KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
423KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
424KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
425
426# Make variables (CC, etc...)
427CPP		= $(CC) -E
428ifneq ($(LLVM),)
429CC		= clang
430LD		= ld.lld
431AR		= llvm-ar
432NM		= llvm-nm
433OBJCOPY		= llvm-objcopy
434OBJDUMP		= llvm-objdump
435READELF		= llvm-readelf
436STRIP		= llvm-strip
437else
438CC		= $(CROSS_COMPILE)gcc
439LD		= $(CROSS_COMPILE)ld
440AR		= $(CROSS_COMPILE)ar
441NM		= $(CROSS_COMPILE)nm
442OBJCOPY		= $(CROSS_COMPILE)objcopy
443OBJDUMP		= $(CROSS_COMPILE)objdump
444READELF		= $(CROSS_COMPILE)readelf
445STRIP		= $(CROSS_COMPILE)strip
446endif
447PAHOLE		= pahole
448RESOLVE_BTFIDS	= $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
449LEX		= flex
450YACC		= bison
451AWK		= awk
452INSTALLKERNEL  := installkernel
453DEPMOD		= depmod
454PERL		= perl
455PYTHON3		= python3
456CHECK		= sparse
457BASH		= bash
458KGZIP		= gzip
459KBZIP2		= bzip2
460KLZOP		= lzop
461LZMA		= lzma
462LZ4		= lz4c
463XZ		= xz
464ZSTD		= zstd
465
466CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
467		  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
468NOSTDINC_FLAGS :=
469CFLAGS_MODULE   =
470AFLAGS_MODULE   =
471LDFLAGS_MODULE  =
472CFLAGS_KERNEL	=
473AFLAGS_KERNEL	=
474LDFLAGS_vmlinux =
475
476# Use USERINCLUDE when you must reference the UAPI directories only.
477USERINCLUDE    := \
478		-I$(srctree)/arch/$(SRCARCH)/include/uapi \
479		-I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
480		-I$(srctree)/include/uapi \
481		-I$(objtree)/include/generated/uapi \
482                -include $(srctree)/include/linux/compiler-version.h \
483                -include $(srctree)/include/linux/kconfig.h
484
485# Use LINUXINCLUDE when you must reference the include/ directory.
486# Needed to be compatible with the O= option
487LINUXINCLUDE    := \
488		-I$(srctree)/arch/$(SRCARCH)/include \
489		-I$(objtree)/arch/$(SRCARCH)/include/generated \
490		$(if $(building_out_of_srctree),-I$(srctree)/include) \
491		-I$(objtree)/include \
492		$(USERINCLUDE)
493
494KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
495KBUILD_CFLAGS   := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
496		   -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
497		   -Werror=implicit-function-declaration -Werror=implicit-int \
498		   -Werror=return-type -Wno-format-security \
499		   -std=gnu89
500KBUILD_CPPFLAGS := -D__KERNEL__
501KBUILD_AFLAGS_KERNEL :=
502KBUILD_CFLAGS_KERNEL :=
503KBUILD_AFLAGS_MODULE  := -DMODULE
504KBUILD_CFLAGS_MODULE  := -DMODULE
505KBUILD_LDFLAGS_MODULE :=
506KBUILD_LDFLAGS :=
507CLANG_FLAGS :=
508
509export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC
510export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
511export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
512export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
513export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
514
515export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
516export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
517export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
518export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
519export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
520
521# Files to ignore in find ... statements
522
523export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
524			  -name CVS -o -name .pc -o -name .hg -o -name .git \) \
525			  -prune -o
526export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
527			 --exclude CVS --exclude .pc --exclude .hg --exclude .git
528
529# ===========================================================================
530# Rules shared between *config targets and build targets
531
532# Basic helpers built in scripts/basic/
533PHONY += scripts_basic
534scripts_basic:
535	$(Q)$(MAKE) $(build)=scripts/basic
536	$(Q)rm -f .tmp_quiet_recordmcount
537
538PHONY += outputmakefile
539# Before starting out-of-tree build, make sure the source tree is clean.
540# outputmakefile generates a Makefile in the output directory, if using a
541# separate output directory. This allows convenient use of make in the
542# output directory.
543# At the same time when output Makefile generated, generate .gitignore to
544# ignore whole output directory
545outputmakefile:
546ifdef building_out_of_srctree
547	$(Q)if [ -f $(srctree)/.config -o \
548		 -d $(srctree)/include/config -o \
549		 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
550		echo >&2 "***"; \
551		echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
552		echo >&2 "*** in $(abs_srctree)";\
553		echo >&2 "***"; \
554		false; \
555	fi
556	$(Q)ln -fsn $(srctree) source
557	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile $(srctree)
558	$(Q)test -e .gitignore || \
559	{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
560endif
561
562# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
563# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
564# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
565# and from include/config/auto.conf.cmd to detect the compiler upgrade.
566CC_VERSION_TEXT = $(shell $(CC) --version 2>/dev/null | head -n 1 | sed 's/\#//g')
567
568ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
569ifneq ($(CROSS_COMPILE),)
570CLANG_FLAGS	+= --target=$(notdir $(CROSS_COMPILE:%-=%))
571GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
572CLANG_FLAGS	+= --prefix=$(GCC_TOOLCHAIN_DIR)$(notdir $(CROSS_COMPILE))
573GCC_TOOLCHAIN	:= $(realpath $(GCC_TOOLCHAIN_DIR)/..)
574endif
575ifneq ($(GCC_TOOLCHAIN),)
576CLANG_FLAGS	+= --gcc-toolchain=$(GCC_TOOLCHAIN)
577endif
578ifneq ($(LLVM_IAS),1)
579CLANG_FLAGS	+= -no-integrated-as
580endif
581CLANG_FLAGS	+= -Werror=unknown-warning-option
582KBUILD_CFLAGS	+= $(CLANG_FLAGS)
583KBUILD_AFLAGS	+= $(CLANG_FLAGS)
584export CLANG_FLAGS
585endif
586
587ifdef config-build
588# ===========================================================================
589# *config targets only - make sure prerequisites are updated, and descend
590# in scripts/kconfig to make the *config target
591
592# Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
593# KBUILD_DEFCONFIG may point out an alternative default configuration
594# used for 'make defconfig'
595include arch/$(SRCARCH)/Makefile
596export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
597
598config: outputmakefile scripts_basic FORCE
599	$(Q)$(MAKE) $(build)=scripts/kconfig $@
600
601%config: outputmakefile scripts_basic FORCE
602	$(Q)$(MAKE) $(build)=scripts/kconfig $@
603
604else #!config-build
605# ===========================================================================
606# Build targets only - this includes vmlinux, arch specific targets, clean
607# targets and others. In general all targets except *config targets.
608
609# If building an external module we do not care about the all: rule
610# but instead __all depend on modules
611PHONY += all
612ifeq ($(KBUILD_EXTMOD),)
613__all: all
614else
615__all: modules
616endif
617
618# Decide whether to build built-in, modular, or both.
619# Normally, just do built-in.
620
621KBUILD_MODULES :=
622KBUILD_BUILTIN := 1
623
624# If we have only "make modules", don't compile built-in objects.
625ifeq ($(MAKECMDGOALS),modules)
626  KBUILD_BUILTIN :=
627endif
628
629# If we have "make <whatever> modules", compile modules
630# in addition to whatever we do anyway.
631# Just "make" or "make all" shall build modules as well
632
633ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
634  KBUILD_MODULES := 1
635endif
636
637ifeq ($(MAKECMDGOALS),)
638  KBUILD_MODULES := 1
639endif
640
641export KBUILD_MODULES KBUILD_BUILTIN
642
643ifdef need-config
644include include/config/auto.conf
645endif
646
647ifeq ($(KBUILD_EXTMOD),)
648# Objects we will link into vmlinux / subdirs we need to visit
649core-y		:= init/ usr/
650drivers-y	:= drivers/ sound/
651drivers-$(CONFIG_SAMPLES) += samples/
652drivers-$(CONFIG_NET) += net/
653drivers-y	+= virt/
654libs-y		:= lib/
655endif # KBUILD_EXTMOD
656
657# The all: target is the default when no target is given on the
658# command line.
659# This allow a user to issue only 'make' to build a kernel including modules
660# Defaults to vmlinux, but the arch makefile usually adds further targets
661all: vmlinux
662
663CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage \
664	$(call cc-option,-fno-tree-loop-im) \
665	$(call cc-disable-warning,maybe-uninitialized,)
666export CFLAGS_GCOV
667
668# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
669ifdef CONFIG_FUNCTION_TRACER
670  CC_FLAGS_FTRACE := -pg
671endif
672
673RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
674RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
675RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
676RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
677RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
678RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
679export RETPOLINE_CFLAGS
680export RETPOLINE_VDSO_CFLAGS
681
682include arch/$(SRCARCH)/Makefile
683
684ifdef need-config
685ifdef may-sync-config
686# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
687# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
688# because some architectures define CROSS_COMPILE there.
689include include/config/auto.conf.cmd
690
691$(KCONFIG_CONFIG):
692	@echo >&2 '***'
693	@echo >&2 '*** Configuration file "$@" not found!'
694	@echo >&2 '***'
695	@echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
696	@echo >&2 '*** "make menuconfig" or "make xconfig").'
697	@echo >&2 '***'
698	@/bin/false
699
700# The actual configuration files used during the build are stored in
701# include/generated/ and include/config/. Update them if .config is newer than
702# include/config/auto.conf (which mirrors .config).
703#
704# This exploits the 'multi-target pattern rule' trick.
705# The syncconfig should be executed only once to make all the targets.
706# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
707quiet_cmd_syncconfig = SYNC    $@
708      cmd_syncconfig = $(MAKE) -f $(srctree)/Makefile syncconfig
709
710%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h: $(KCONFIG_CONFIG)
711	+$(call cmd,syncconfig)
712else # !may-sync-config
713# External modules and some install targets need include/generated/autoconf.h
714# and include/config/auto.conf but do not care if they are up-to-date.
715# Use auto.conf to trigger the test
716PHONY += include/config/auto.conf
717
718include/config/auto.conf:
719	$(Q)test -e include/generated/autoconf.h -a -e $@ || (		\
720	echo >&2;							\
721	echo >&2 "  ERROR: Kernel configuration is invalid.";		\
722	echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
723	echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";	\
724	echo >&2 ;							\
725	/bin/false)
726
727endif # may-sync-config
728endif # need-config
729
730KBUILD_CFLAGS	+= $(call cc-option,-fno-delete-null-pointer-checks,)
731KBUILD_CFLAGS	+= $(call cc-disable-warning,frame-address,)
732KBUILD_CFLAGS	+= $(call cc-disable-warning, format-truncation)
733KBUILD_CFLAGS	+= $(call cc-disable-warning, format-overflow)
734KBUILD_CFLAGS	+= $(call cc-disable-warning, address-of-packed-member)
735
736ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
737KBUILD_CFLAGS += -O2
738else ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3
739KBUILD_CFLAGS += -O3
740else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
741KBUILD_CFLAGS += -Os
742endif
743
744# Tell gcc to never replace conditional load with a non-conditional one
745KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
746KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
747
748ifdef CONFIG_READABLE_ASM
749# Disable optimizations that make assembler listings hard to read.
750# reorder blocks reorders the control in the function
751# ipa clone creates specialized cloned functions
752# partial inlining inlines only parts of functions
753KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
754                 $(call cc-option,-fno-ipa-cp-clone,) \
755                 $(call cc-option,-fno-partial-inlining)
756endif
757
758ifneq ($(CONFIG_FRAME_WARN),0)
759KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
760endif
761
762stackp-flags-y                                    := -fno-stack-protector
763stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
764stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
765
766KBUILD_CFLAGS += $(stackp-flags-y)
767
768ifdef CONFIG_CC_IS_CLANG
769KBUILD_CPPFLAGS += -Qunused-arguments
770KBUILD_CFLAGS += -Wno-format-invalid-specifier
771KBUILD_CFLAGS += -Wno-gnu
772# CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
773# source of a reference will be _MergedGlobals and not on of the whitelisted names.
774# See modpost pattern 2
775KBUILD_CFLAGS += -mno-global-merge
776else
777
778# These warnings generated too much noise in a regular build.
779# Use make W=1 to enable them (see scripts/Makefile.extrawarn)
780KBUILD_CFLAGS += -Wno-unused-but-set-variable
781
782# Warn about unmarked fall-throughs in switch statement.
783# Disabled for clang while comment to attribute conversion happens and
784# https://github.com/ClangBuiltLinux/linux/issues/636 is discussed.
785KBUILD_CFLAGS += $(call cc-option,-Wimplicit-fallthrough,)
786endif
787
788KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
789ifdef CONFIG_FRAME_POINTER
790KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
791else
792# Some targets (ARM with Thumb2, for example), can't be built with frame
793# pointers.  For those, we don't have FUNCTION_TRACER automatically
794# select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
795# incompatible with -fomit-frame-pointer with current GCC, so we don't use
796# -fomit-frame-pointer with FUNCTION_TRACER.
797ifndef CONFIG_FUNCTION_TRACER
798KBUILD_CFLAGS	+= -fomit-frame-pointer
799endif
800endif
801
802# Initialize all stack variables with a 0xAA pattern.
803ifdef CONFIG_INIT_STACK_ALL_PATTERN
804KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
805endif
806
807# Initialize all stack variables with a zero value.
808ifdef CONFIG_INIT_STACK_ALL_ZERO
809# Future support for zero initialization is still being debated, see
810# https://bugs.llvm.org/show_bug.cgi?id=45497. These flags are subject to being
811# renamed or dropped.
812KBUILD_CFLAGS	+= -ftrivial-auto-var-init=zero
813KBUILD_CFLAGS	+= -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
814endif
815
816# While VLAs have been removed, GCC produces unreachable stack probes
817# for the randomize_kstack_offset feature. Disable it for all compilers.
818KBUILD_CFLAGS	+= $(call cc-option, -fno-stack-clash-protection)
819
820DEBUG_CFLAGS	:=
821
822# Workaround for GCC versions < 5.0
823# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61801
824ifdef CONFIG_CC_IS_GCC
825DEBUG_CFLAGS	+= $(call cc-ifversion, -lt, 0500, $(call cc-option, -fno-var-tracking-assignments))
826endif
827
828ifdef CONFIG_DEBUG_INFO
829
830ifdef CONFIG_DEBUG_INFO_SPLIT
831DEBUG_CFLAGS	+= -gsplit-dwarf
832else
833DEBUG_CFLAGS	+= -g
834endif
835
836ifneq ($(LLVM_IAS),1)
837KBUILD_AFLAGS	+= -Wa,-gdwarf-2
838endif
839
840ifndef CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT
841dwarf-version-$(CONFIG_DEBUG_INFO_DWARF4) := 4
842dwarf-version-$(CONFIG_DEBUG_INFO_DWARF5) := 5
843DEBUG_CFLAGS	+= -gdwarf-$(dwarf-version-y)
844endif
845
846ifdef CONFIG_DEBUG_INFO_REDUCED
847DEBUG_CFLAGS	+= $(call cc-option, -femit-struct-debug-baseonly) \
848		   $(call cc-option,-fno-var-tracking)
849endif
850
851ifdef CONFIG_DEBUG_INFO_COMPRESSED
852DEBUG_CFLAGS	+= -gz=zlib
853KBUILD_AFLAGS	+= -gz=zlib
854KBUILD_LDFLAGS	+= --compress-debug-sections=zlib
855endif
856
857endif # CONFIG_DEBUG_INFO
858
859KBUILD_CFLAGS += $(DEBUG_CFLAGS)
860export DEBUG_CFLAGS
861
862ifdef CONFIG_FUNCTION_TRACER
863ifdef CONFIG_FTRACE_MCOUNT_USE_CC
864  CC_FLAGS_FTRACE	+= -mrecord-mcount
865  ifdef CONFIG_HAVE_NOP_MCOUNT
866    ifeq ($(call cc-option-yn, -mnop-mcount),y)
867      CC_FLAGS_FTRACE	+= -mnop-mcount
868      CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
869    endif
870  endif
871endif
872ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
873  CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
874endif
875ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
876  ifdef CONFIG_HAVE_C_RECORDMCOUNT
877    BUILD_C_RECORDMCOUNT := y
878    export BUILD_C_RECORDMCOUNT
879  endif
880endif
881ifdef CONFIG_HAVE_FENTRY
882  ifeq ($(call cc-option-yn, -mfentry),y)
883    CC_FLAGS_FTRACE	+= -mfentry
884    CC_FLAGS_USING	+= -DCC_USING_FENTRY
885  endif
886endif
887export CC_FLAGS_FTRACE
888KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
889KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
890endif
891
892# We trigger additional mismatches with less inlining
893ifdef CONFIG_DEBUG_SECTION_MISMATCH
894KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
895endif
896
897ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
898KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
899LDFLAGS_vmlinux += --gc-sections
900endif
901
902ifdef CONFIG_SHADOW_CALL_STACK
903CC_FLAGS_SCS	:= -fsanitize=shadow-call-stack
904KBUILD_CFLAGS	+= $(CC_FLAGS_SCS)
905export CC_FLAGS_SCS
906endif
907
908ifdef CONFIG_LTO_CLANG
909ifdef CONFIG_LTO_CLANG_THIN
910CC_FLAGS_LTO	:= -flto=thin -fsplit-lto-unit
911KBUILD_LDFLAGS	+= --thinlto-cache-dir=$(extmod-prefix).thinlto-cache
912else
913CC_FLAGS_LTO	:= -flto
914endif
915CC_FLAGS_LTO	+= -fvisibility=hidden
916
917# Limit inlining across translation units to reduce binary size
918KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
919endif
920
921ifdef CONFIG_LTO
922KBUILD_CFLAGS	+= -fno-lto $(CC_FLAGS_LTO)
923KBUILD_AFLAGS	+= -fno-lto
924export CC_FLAGS_LTO
925endif
926
927ifdef CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_32B
928KBUILD_CFLAGS += -falign-functions=32
929endif
930
931# arch Makefile may override CC so keep this after arch Makefile is included
932NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
933
934# warn about C99 declaration after statement
935KBUILD_CFLAGS += -Wdeclaration-after-statement
936
937# Variable Length Arrays (VLAs) should not be used anywhere in the kernel
938KBUILD_CFLAGS += -Wvla
939
940# disable pointer signed / unsigned warnings in gcc 4.0
941KBUILD_CFLAGS += -Wno-pointer-sign
942
943# disable stringop warnings in gcc 8+
944KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
945
946# We'll want to enable this eventually, but it's not going away for 5.7 at least
947KBUILD_CFLAGS += $(call cc-disable-warning, zero-length-bounds)
948KBUILD_CFLAGS += $(call cc-disable-warning, array-bounds)
949KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
950
951# Another good warning that we'll want to enable eventually
952KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
953
954# Enabled with W=2, disabled by default as noisy
955KBUILD_CFLAGS += $(call cc-disable-warning, maybe-uninitialized)
956
957# disable invalid "can't wrap" optimizations for signed / pointers
958KBUILD_CFLAGS	+= -fno-strict-overflow
959
960# Make sure -fstack-check isn't enabled (like gentoo apparently did)
961KBUILD_CFLAGS  += -fno-stack-check
962
963# conserve stack if available
964KBUILD_CFLAGS   += $(call cc-option,-fconserve-stack)
965
966# Prohibit date/time macros, which would make the build non-deterministic
967KBUILD_CFLAGS   += -Werror=date-time
968
969# enforce correct pointer usage
970KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)
971
972# Require designated initializers for all marked structures
973KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)
974
975# change __FILE__ to the relative path from the srctree
976KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
977
978# include additional Makefiles when needed
979include-y			:= scripts/Makefile.extrawarn
980include-$(CONFIG_KASAN)		+= scripts/Makefile.kasan
981include-$(CONFIG_KCSAN)		+= scripts/Makefile.kcsan
982include-$(CONFIG_UBSAN)		+= scripts/Makefile.ubsan
983include-$(CONFIG_KCOV)		+= scripts/Makefile.kcov
984include-$(CONFIG_GCC_PLUGINS)	+= scripts/Makefile.gcc-plugins
985
986include $(addprefix $(srctree)/, $(include-y))
987
988# scripts/Makefile.gcc-plugins is intentionally included last.
989# Do not add $(call cc-option,...) below this line. When you build the kernel
990# from the clean source tree, the GCC plugins do not exist at this point.
991
992# Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
993KBUILD_CPPFLAGS += $(KCPPFLAGS)
994KBUILD_AFLAGS   += $(KAFLAGS)
995KBUILD_CFLAGS   += $(KCFLAGS)
996
997KBUILD_LDFLAGS_MODULE += --build-id=sha1
998LDFLAGS_vmlinux += --build-id=sha1
999
1000ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1001LDFLAGS_vmlinux	+= $(call ld-option, -X,)
1002endif
1003
1004ifeq ($(CONFIG_RELR),y)
1005LDFLAGS_vmlinux	+= --pack-dyn-relocs=relr
1006endif
1007
1008# We never want expected sections to be placed heuristically by the
1009# linker. All sections should be explicitly named in the linker script.
1010ifdef CONFIG_LD_ORPHAN_WARN
1011LDFLAGS_vmlinux += --orphan-handling=warn
1012endif
1013
1014# Align the bit size of userspace programs with the kernel
1015KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1016KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1017
1018# make the checker run with the right architecture
1019CHECKFLAGS += --arch=$(ARCH)
1020
1021# insure the checker run with the right endianness
1022CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1023
1024# the checker needs the correct machine size
1025CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1026
1027# Default kernel image to build when no specific target is given.
1028# KBUILD_IMAGE may be overruled on the command line or
1029# set in the environment
1030# Also any assignments in arch/$(ARCH)/Makefile take precedence over
1031# this default value
1032export KBUILD_IMAGE ?= vmlinux
1033
1034#
1035# INSTALL_PATH specifies where to place the updated kernel and system map
1036# images. Default is /boot, but you can set it to other values
1037export	INSTALL_PATH ?= /boot
1038
1039#
1040# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1041# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1042# an argument if needed. Otherwise it defaults to the kernel install path
1043#
1044export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1045
1046#
1047# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1048# relocations required by build roots.  This is not defined in the
1049# makefile but the argument can be passed to make if needed.
1050#
1051
1052MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1053export MODLIB
1054
1055#
1056# INSTALL_MOD_STRIP, if defined, will cause modules to be
1057# stripped after they are installed.  If INSTALL_MOD_STRIP is '1', then
1058# the default option --strip-debug will be used.  Otherwise,
1059# INSTALL_MOD_STRIP value will be used as the options to the strip command.
1060
1061ifdef INSTALL_MOD_STRIP
1062ifeq ($(INSTALL_MOD_STRIP),1)
1063mod_strip_cmd = $(STRIP) --strip-debug
1064else
1065mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
1066endif # INSTALL_MOD_STRIP=1
1067else
1068mod_strip_cmd = true
1069endif # INSTALL_MOD_STRIP
1070export mod_strip_cmd
1071
1072# CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
1073# after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
1074# or CONFIG_MODULE_COMPRESS_XZ.
1075
1076mod_compress_cmd = true
1077ifdef CONFIG_MODULE_COMPRESS
1078  ifdef CONFIG_MODULE_COMPRESS_GZIP
1079    mod_compress_cmd = $(KGZIP) -n -f
1080  endif # CONFIG_MODULE_COMPRESS_GZIP
1081  ifdef CONFIG_MODULE_COMPRESS_XZ
1082    mod_compress_cmd = $(XZ) --lzma2=dict=2MiB -f
1083  endif # CONFIG_MODULE_COMPRESS_XZ
1084endif # CONFIG_MODULE_COMPRESS
1085export mod_compress_cmd
1086
1087ifdef CONFIG_MODULE_SIG_ALL
1088$(eval $(call config_filename,MODULE_SIG_KEY))
1089
1090mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
1091else
1092mod_sign_cmd = true
1093endif
1094export mod_sign_cmd
1095
1096HOST_LIBELF_LIBS = $(shell pkg-config libelf --libs 2>/dev/null || echo -lelf)
1097
1098has_libelf = $(call try-run,\
1099               echo "int main() {}" | $(HOSTCC) -xc -o /dev/null $(HOST_LIBELF_LIBS) -,1,0)
1100
1101ifdef CONFIG_STACK_VALIDATION
1102  ifeq ($(has_libelf),1)
1103    objtool_target := tools/objtool FORCE
1104  else
1105    SKIP_STACK_VALIDATION := 1
1106    export SKIP_STACK_VALIDATION
1107  endif
1108endif
1109
1110PHONY += resolve_btfids_clean
1111
1112resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1113
1114# tools/bpf/resolve_btfids directory might not exist
1115# in output directory, skip its clean in that case
1116resolve_btfids_clean:
1117ifneq ($(wildcard $(resolve_btfids_O)),)
1118	$(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1119endif
1120
1121ifdef CONFIG_BPF
1122ifdef CONFIG_DEBUG_INFO_BTF
1123  ifeq ($(has_libelf),1)
1124    resolve_btfids_target := tools/bpf/resolve_btfids FORCE
1125  else
1126    ERROR_RESOLVE_BTFIDS := 1
1127  endif
1128endif # CONFIG_DEBUG_INFO_BTF
1129endif # CONFIG_BPF
1130
1131PHONY += prepare0
1132
1133extmod-prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
1134export MODORDER := $(extmod-prefix)modules.order
1135export MODULES_NSDEPS := $(extmod-prefix)modules.nsdeps
1136
1137ifeq ($(KBUILD_EXTMOD),)
1138core-y		+= kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
1139
1140vmlinux-dirs	:= $(patsubst %/,%,$(filter %/, \
1141		     $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
1142		     $(libs-y) $(libs-m)))
1143
1144vmlinux-alldirs	:= $(sort $(vmlinux-dirs) Documentation \
1145		     $(patsubst %/,%,$(filter %/, $(core-) \
1146			$(drivers-) $(libs-))))
1147
1148subdir-modorder := $(addsuffix modules.order,$(filter %/, \
1149			$(core-y) $(core-m) $(libs-y) $(libs-m) \
1150			$(drivers-y) $(drivers-m)))
1151
1152build-dirs	:= $(vmlinux-dirs)
1153clean-dirs	:= $(vmlinux-alldirs)
1154
1155# Externally visible symbols (used by link-vmlinux.sh)
1156KBUILD_VMLINUX_OBJS := $(head-y) $(patsubst %/,%/built-in.a, $(core-y))
1157KBUILD_VMLINUX_OBJS += $(addsuffix built-in.a, $(filter %/, $(libs-y)))
1158ifdef CONFIG_MODULES
1159KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1160KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1161else
1162KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1163endif
1164KBUILD_VMLINUX_OBJS += $(patsubst %/,%/built-in.a, $(drivers-y))
1165
1166export KBUILD_VMLINUX_OBJS KBUILD_VMLINUX_LIBS
1167export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1168# used by scripts/Makefile.package
1169export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) LICENSES arch include scripts tools)
1170
1171vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
1172
1173# Recurse until adjust_autoksyms.sh is satisfied
1174PHONY += autoksyms_recursive
1175ifdef CONFIG_TRIM_UNUSED_KSYMS
1176# For the kernel to actually contain only the needed exported symbols,
1177# we have to build modules as well to determine what those symbols are.
1178# (this can be evaluated only once include/config/auto.conf has been included)
1179KBUILD_MODULES := 1
1180
1181autoksyms_recursive: descend modules.order
1182	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1183	  "$(MAKE) -f $(srctree)/Makefile vmlinux"
1184endif
1185
1186autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1187
1188quiet_cmd_autoksyms_h = GEN     $@
1189      cmd_autoksyms_h = mkdir -p $(dir $@); \
1190			$(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@
1191
1192$(autoksyms_h):
1193	$(call cmd,autoksyms_h)
1194
1195ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1196
1197# Final link of vmlinux with optional arch pass after final link
1198cmd_link-vmlinux =                                                 \
1199	$(CONFIG_SHELL) $< "$(LD)" "$(KBUILD_LDFLAGS)" "$(LDFLAGS_vmlinux)";    \
1200	$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1201
1202vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1203	+$(call if_changed,link-vmlinux)
1204
1205targets := vmlinux
1206
1207# The actual objects are generated when descending,
1208# make sure no implicit rule kicks in
1209$(sort $(vmlinux-deps) $(subdir-modorder)): descend ;
1210
1211filechk_kernel.release = \
1212	echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1213
1214# Store (new) KERNELRELEASE string in include/config/kernel.release
1215include/config/kernel.release: FORCE
1216	$(call filechk,kernel.release)
1217
1218# Additional helpers built in scripts/
1219# Carefully list dependencies so we do not try to build scripts twice
1220# in parallel
1221PHONY += scripts
1222scripts: scripts_basic scripts_dtc
1223	$(Q)$(MAKE) $(build)=$(@)
1224
1225# Things we need to do before we recursively start building the kernel
1226# or the modules are listed in "prepare".
1227# A multi level approach is used. prepareN is processed before prepareN-1.
1228# archprepare is used in arch Makefiles and when processed asm symlink,
1229# version.h and scripts_basic is processed / created.
1230
1231PHONY += prepare archprepare
1232
1233archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1234	asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h \
1235	include/generated/autoconf.h
1236
1237prepare0: archprepare
1238	$(Q)$(MAKE) $(build)=scripts/mod
1239	$(Q)$(MAKE) $(build)=.
1240
1241# All the preparing..
1242prepare: prepare0 prepare-objtool prepare-resolve_btfids
1243
1244# Support for using generic headers in asm-generic
1245asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1246
1247PHONY += asm-generic uapi-asm-generic
1248asm-generic: uapi-asm-generic
1249	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1250	generic=include/asm-generic
1251uapi-asm-generic:
1252	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1253	generic=include/uapi/asm-generic
1254
1255PHONY += prepare-objtool prepare-resolve_btfids
1256prepare-objtool: $(objtool_target)
1257ifeq ($(SKIP_STACK_VALIDATION),1)
1258ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
1259	@echo "error: Cannot generate __mcount_loc for CONFIG_DYNAMIC_FTRACE=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1260	@false
1261endif
1262ifdef CONFIG_UNWINDER_ORC
1263	@echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1264	@false
1265else
1266	@echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1267endif
1268endif
1269
1270prepare-resolve_btfids: $(resolve_btfids_target)
1271ifeq ($(ERROR_RESOLVE_BTFIDS),1)
1272	@echo "error: Cannot resolve BTF IDs for CONFIG_DEBUG_INFO_BTF, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1273	@false
1274endif
1275# Generate some files
1276# ---------------------------------------------------------------------------
1277
1278# KERNELRELEASE can change from a few different places, meaning version.h
1279# needs to be updated, so this check is forced on all builds
1280
1281uts_len := 64
1282define filechk_utsrelease.h
1283	if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1284	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1285	  exit 1;                                                         \
1286	fi;                                                               \
1287	echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1288endef
1289
1290define filechk_version.h
1291	if [ $(SUBLEVEL) -gt 255 ]; then                                 \
1292		echo \#define LINUX_VERSION_CODE $(shell                 \
1293		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1294	else                                                             \
1295		echo \#define LINUX_VERSION_CODE $(shell                 \
1296		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1297	fi;                                                              \
1298	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
1299	((c) > 255 ? 255 : (c)))';                                       \
1300	echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
1301	echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
1302	echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1303endef
1304
1305$(version_h): PATCHLEVEL := $(if $(PATCHLEVEL), $(PATCHLEVEL), 0)
1306$(version_h): SUBLEVEL := $(if $(SUBLEVEL), $(SUBLEVEL), 0)
1307$(version_h): FORCE
1308	$(call filechk,version.h)
1309
1310include/generated/utsrelease.h: include/config/kernel.release FORCE
1311	$(call filechk,utsrelease.h)
1312
1313PHONY += headerdep
1314headerdep:
1315	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1316	$(srctree)/scripts/headerdep.pl -I$(srctree)/include
1317
1318# ---------------------------------------------------------------------------
1319# Kernel headers
1320
1321#Default location for installed headers
1322export INSTALL_HDR_PATH = $(objtree)/usr
1323
1324quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1325      cmd_headers_install = \
1326	mkdir -p $(INSTALL_HDR_PATH); \
1327	rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1328	usr/include $(INSTALL_HDR_PATH)
1329
1330PHONY += headers_install
1331headers_install: headers
1332	$(call cmd,headers_install)
1333
1334PHONY += archheaders archscripts
1335
1336hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1337
1338PHONY += headers
1339headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1340	$(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1341	  $(error Headers not exportable for the $(SRCARCH) architecture))
1342	$(Q)$(MAKE) $(hdr-inst)=include/uapi
1343	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1344
1345# Deprecated. It is no-op now.
1346PHONY += headers_check
1347headers_check:
1348	@:
1349
1350ifdef CONFIG_HEADERS_INSTALL
1351prepare: headers
1352endif
1353
1354PHONY += scripts_unifdef
1355scripts_unifdef: scripts_basic
1356	$(Q)$(MAKE) $(build)=scripts scripts/unifdef
1357
1358# ---------------------------------------------------------------------------
1359# Kernel selftest
1360
1361PHONY += kselftest
1362kselftest:
1363	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1364
1365kselftest-%: FORCE
1366	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1367
1368PHONY += kselftest-merge
1369kselftest-merge:
1370	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1371	$(Q)find $(srctree)/tools/testing/selftests -name config | \
1372		xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1373	$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1374
1375# ---------------------------------------------------------------------------
1376# Devicetree files
1377
1378ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1379dtstree := arch/$(SRCARCH)/boot/dts
1380endif
1381
1382ifneq ($(dtstree),)
1383
1384%.dtb: include/config/kernel.release scripts_dtc
1385	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1386
1387%.dtbo: include/config/kernel.release scripts_dtc
1388	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1389
1390PHONY += dtbs dtbs_install dtbs_check
1391dtbs: include/config/kernel.release scripts_dtc
1392	$(Q)$(MAKE) $(build)=$(dtstree)
1393
1394ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1395export CHECK_DTBS=y
1396dtbs: dt_binding_check
1397endif
1398
1399dtbs_check: dtbs
1400
1401dtbs_install:
1402	$(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1403
1404ifdef CONFIG_OF_EARLY_FLATTREE
1405all: dtbs
1406endif
1407
1408endif
1409
1410PHONY += scripts_dtc
1411scripts_dtc: scripts_basic
1412	$(Q)$(MAKE) $(build)=scripts/dtc
1413
1414ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1415export CHECK_DT_BINDING=y
1416endif
1417
1418PHONY += dt_binding_check
1419dt_binding_check: scripts_dtc
1420	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1421
1422# ---------------------------------------------------------------------------
1423# Modules
1424
1425ifdef CONFIG_MODULES
1426
1427# By default, build modules as well
1428
1429all: modules
1430
1431# When we're building modules with modversions, we need to consider
1432# the built-in objects during the descend as well, in order to
1433# make sure the checksums are up to date before we record them.
1434ifdef CONFIG_MODVERSIONS
1435  KBUILD_BUILTIN := 1
1436endif
1437
1438# Build modules
1439#
1440# A module can be listed more than once in obj-m resulting in
1441# duplicate lines in modules.order files.  Those are removed
1442# using awk while concatenating to the final file.
1443
1444PHONY += modules
1445modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_check modules_prepare
1446	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1447
1448PHONY += modules_check
1449modules_check: modules.order
1450	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1451
1452cmd_modules_order = $(AWK) '!x[$$0]++' $(real-prereqs) > $@
1453
1454modules.order: $(subdir-modorder) FORCE
1455	$(call if_changed,modules_order)
1456
1457targets += modules.order
1458
1459# Target to prepare building external modules
1460PHONY += modules_prepare
1461modules_prepare: prepare
1462	$(Q)$(MAKE) $(build)=scripts scripts/module.lds
1463
1464# Target to install modules
1465PHONY += modules_install
1466modules_install: _modinst_ _modinst_post
1467
1468PHONY += _modinst_
1469_modinst_:
1470	@rm -rf $(MODLIB)/kernel
1471	@rm -f $(MODLIB)/source
1472	@mkdir -p $(MODLIB)/kernel
1473	@ln -s $(abspath $(srctree)) $(MODLIB)/source
1474	@if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
1475		rm -f $(MODLIB)/build ; \
1476		ln -s $(CURDIR) $(MODLIB)/build ; \
1477	fi
1478	@sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order
1479	@cp -f modules.builtin $(MODLIB)/
1480	@cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
1481	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1482
1483# This depmod is only for convenience to give the initial
1484# boot a modules.dep even before / is mounted read-write.  However the
1485# boot script depmod is the master version.
1486PHONY += _modinst_post
1487_modinst_post: _modinst_
1488	$(call cmd,depmod)
1489
1490ifeq ($(CONFIG_MODULE_SIG), y)
1491PHONY += modules_sign
1492modules_sign:
1493	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1494endif
1495
1496else # CONFIG_MODULES
1497
1498# Modules not configured
1499# ---------------------------------------------------------------------------
1500
1501PHONY += modules modules_install
1502modules modules_install:
1503	@echo >&2
1504	@echo >&2 "The present kernel configuration has modules disabled."
1505	@echo >&2 "Type 'make config' and enable loadable module support."
1506	@echo >&2 "Then build a kernel with module support enabled."
1507	@echo >&2
1508	@exit 1
1509
1510endif # CONFIG_MODULES
1511
1512###
1513# Cleaning is done on three levels.
1514# make clean     Delete most generated files
1515#                Leave enough to build external modules
1516# make mrproper  Delete the current configuration, and all generated files
1517# make distclean Remove editor backup files, patch leftover files and the like
1518
1519# Directories & files removed with 'make clean'
1520CLEAN_FILES += include/ksym vmlinux.symvers \
1521	       modules.builtin modules.builtin.modinfo modules.nsdeps \
1522	       compile_commands.json .thinlto-cache
1523
1524# Directories & files removed with 'make mrproper'
1525MRPROPER_FILES += include/config include/generated          \
1526		  arch/$(SRCARCH)/include/generated .tmp_objdiff \
1527		  debian snap tar-install \
1528		  .config .config.old .version \
1529		  Module.symvers \
1530		  signing_key.pem signing_key.priv signing_key.x509	\
1531		  x509.genkey extra_certificates signing_key.x509.keyid	\
1532		  signing_key.x509.signer vmlinux-gdb.py \
1533		  *.spec
1534
1535# Directories & files removed with 'make distclean'
1536DISTCLEAN_FILES += tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS
1537
1538# clean - Delete most, but leave enough to build external modules
1539#
1540clean: rm-files := $(CLEAN_FILES)
1541
1542PHONY += archclean vmlinuxclean
1543
1544vmlinuxclean:
1545	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1546	$(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1547
1548clean: archclean vmlinuxclean resolve_btfids_clean
1549
1550# mrproper - Delete all generated files, including .config
1551#
1552mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1553mrproper-dirs      := $(addprefix _mrproper_,scripts)
1554
1555PHONY += $(mrproper-dirs) mrproper
1556$(mrproper-dirs):
1557	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1558
1559mrproper: clean $(mrproper-dirs)
1560	$(call cmd,rmfiles)
1561
1562# distclean
1563#
1564distclean: rm-files := $(wildcard $(DISTCLEAN_FILES))
1565
1566PHONY += distclean
1567
1568distclean: mrproper
1569	$(call cmd,rmfiles)
1570	@find $(srctree) $(RCS_FIND_IGNORE) \
1571		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1572		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
1573		-o -name 'core' \) \
1574		-type f -print | xargs rm -f
1575
1576
1577# Packaging of the kernel to various formats
1578# ---------------------------------------------------------------------------
1579
1580%src-pkg: FORCE
1581	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1582%pkg: include/config/kernel.release FORCE
1583	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1584
1585# Brief documentation of the typical targets used
1586# ---------------------------------------------------------------------------
1587
1588boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1589boards := $(sort $(notdir $(boards)))
1590board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1591board-dirs := $(sort $(notdir $(board-dirs:/=)))
1592
1593PHONY += help
1594help:
1595	@echo  'Cleaning targets:'
1596	@echo  '  clean		  - Remove most generated files but keep the config and'
1597	@echo  '                    enough build support to build external modules'
1598	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
1599	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
1600	@echo  ''
1601	@echo  'Configuration targets:'
1602	@$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1603	@echo  ''
1604	@echo  'Other generic targets:'
1605	@echo  '  all		  - Build all targets marked with [*]'
1606	@echo  '* vmlinux	  - Build the bare kernel'
1607	@echo  '* modules	  - Build all modules'
1608	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1609	@echo  '  dir/            - Build all files in dir and below'
1610	@echo  '  dir/file.[ois]  - Build specified target only'
1611	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1612	@echo  '                    (requires compiler support for LLVM assembly generation)'
1613	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1614	@echo  '                    (requires a recent binutils and recent build (System.map))'
1615	@echo  '  dir/file.ko     - Build module including final link'
1616	@echo  '  modules_prepare - Set up for building external modules'
1617	@echo  '  tags/TAGS	  - Generate tags file for editors'
1618	@echo  '  cscope	  - Generate cscope index'
1619	@echo  '  gtags           - Generate GNU GLOBAL index'
1620	@echo  '  kernelrelease	  - Output the release version string (use with make -s)'
1621	@echo  '  kernelversion	  - Output the version stored in Makefile (use with make -s)'
1622	@echo  '  image_name	  - Output the image name (use with make -s)'
1623	@echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1624	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1625	 echo  ''
1626	@echo  'Static analysers:'
1627	@echo  '  checkstack      - Generate a list of stack hogs'
1628	@echo  '  versioncheck    - Sanity check on version.h usage'
1629	@echo  '  includecheck    - Check for duplicate included header files'
1630	@echo  '  export_report   - List the usages of all exported symbols'
1631	@echo  '  headerdep       - Detect inclusion cycles in headers'
1632	@echo  '  coccicheck      - Check with Coccinelle'
1633	@echo  '  clang-analyzer  - Check with clang static analyzer'
1634	@echo  '  clang-tidy      - Check with clang-tidy'
1635	@echo  ''
1636	@echo  'Tools:'
1637	@echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1638	@echo  ''
1639	@echo  'Kernel selftest:'
1640	@echo  '  kselftest         - Build and run kernel selftest'
1641	@echo  '                      Build, install, and boot kernel before'
1642	@echo  '                      running kselftest on it'
1643	@echo  '                      Run as root for full coverage'
1644	@echo  '  kselftest-all     - Build kernel selftest'
1645	@echo  '  kselftest-install - Build and install kernel selftest'
1646	@echo  '  kselftest-clean   - Remove all generated kselftest files'
1647	@echo  '  kselftest-merge   - Merge all the config dependencies of'
1648	@echo  '		      kselftest to existing .config.'
1649	@echo  ''
1650	@$(if $(dtstree), \
1651		echo 'Devicetree:'; \
1652		echo '* dtbs             - Build device tree blobs for enabled boards'; \
1653		echo '  dtbs_install     - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1654		echo '  dt_binding_check - Validate device tree binding documents'; \
1655		echo '  dtbs_check       - Validate device tree source files';\
1656		echo '')
1657
1658	@echo 'Userspace tools targets:'
1659	@echo '  use "make tools/help"'
1660	@echo '  or  "cd tools; make help"'
1661	@echo  ''
1662	@echo  'Kernel packaging:'
1663	@$(MAKE) -f $(srctree)/scripts/Makefile.package help
1664	@echo  ''
1665	@echo  'Documentation targets:'
1666	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1667	@echo  ''
1668	@echo  'Architecture specific targets ($(SRCARCH)):'
1669	@$(if $(archhelp),$(archhelp),\
1670		echo '  No architecture specific help defined for $(SRCARCH)')
1671	@echo  ''
1672	@$(if $(boards), \
1673		$(foreach b, $(boards), \
1674		printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1675		echo '')
1676	@$(if $(board-dirs), \
1677		$(foreach b, $(board-dirs), \
1678		printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1679		printf "  %-16s - Show all of the above\\n" help-boards; \
1680		echo '')
1681
1682	@echo  '  make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1683	@echo  '  make V=2   [targets] 2 => give reason for rebuild of target'
1684	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1685	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1686	@echo  '                       (sparse by default)'
1687	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1688	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1689	@echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
1690	@echo  '		1: warnings which may be relevant and do not occur too often'
1691	@echo  '		2: warnings which occur quite often but may still be relevant'
1692	@echo  '		3: more obscure warnings, can most likely be ignored'
1693	@echo  '		Multiple levels can be combined with W=12 or W=123'
1694	@echo  ''
1695	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
1696	@echo  'For further info see the ./README file'
1697
1698
1699help-board-dirs := $(addprefix help-,$(board-dirs))
1700
1701help-boards: $(help-board-dirs)
1702
1703boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1704
1705$(help-board-dirs): help-%:
1706	@echo  'Architecture specific targets ($(SRCARCH) $*):'
1707	@$(if $(boards-per-dir), \
1708		$(foreach b, $(boards-per-dir), \
1709		printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1710		echo '')
1711
1712
1713# Documentation targets
1714# ---------------------------------------------------------------------------
1715DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1716	       linkcheckdocs dochelp refcheckdocs
1717PHONY += $(DOC_TARGETS)
1718$(DOC_TARGETS):
1719	$(Q)$(MAKE) $(build)=Documentation $@
1720
1721# Misc
1722# ---------------------------------------------------------------------------
1723
1724PHONY += scripts_gdb
1725scripts_gdb: prepare0
1726	$(Q)$(MAKE) $(build)=scripts/gdb
1727	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1728
1729ifdef CONFIG_GDB_SCRIPTS
1730all: scripts_gdb
1731endif
1732
1733else # KBUILD_EXTMOD
1734
1735###
1736# External module support.
1737# When building external modules the kernel used as basis is considered
1738# read-only, and no consistency checks are made and the make
1739# system is not used on the basis kernel. If updates are required
1740# in the basis kernel ordinary make commands (without M=...) must
1741# be used.
1742#
1743# The following are the only valid targets when building external
1744# modules.
1745# make M=dir clean     Delete all automatically generated files
1746# make M=dir modules   Make all modules in specified dir
1747# make M=dir	       Same as 'make M=dir modules'
1748# make M=dir modules_install
1749#                      Install the modules built in the module directory
1750#                      Assumes install directory is already created
1751
1752# We are always building only modules.
1753KBUILD_BUILTIN :=
1754KBUILD_MODULES := 1
1755
1756build-dirs := $(KBUILD_EXTMOD)
1757PHONY += modules
1758modules: $(MODORDER)
1759	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1760
1761$(MODORDER): descend
1762	@:
1763
1764PHONY += modules_install
1765modules_install: _emodinst_ _emodinst_post
1766
1767install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1768PHONY += _emodinst_
1769_emodinst_:
1770	$(Q)mkdir -p $(MODLIB)/$(install-dir)
1771	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1772
1773PHONY += _emodinst_post
1774_emodinst_post: _emodinst_
1775	$(call cmd,depmod)
1776
1777compile_commands.json: $(extmod-prefix)compile_commands.json
1778PHONY += compile_commands.json
1779
1780clean-dirs := $(KBUILD_EXTMOD)
1781clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1782	$(KBUILD_EXTMOD)/compile_commands.json $(KBUILD_EXTMOD)/.thinlto-cache
1783
1784PHONY += help
1785help:
1786	@echo  '  Building external modules.'
1787	@echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1788	@echo  ''
1789	@echo  '  modules         - default target, build the module(s)'
1790	@echo  '  modules_install - install the module'
1791	@echo  '  clean           - remove generated files in module directory only'
1792	@echo  ''
1793
1794# no-op for external module builds
1795PHONY += prepare modules_prepare
1796
1797endif # KBUILD_EXTMOD
1798
1799# Single targets
1800# ---------------------------------------------------------------------------
1801# To build individual files in subdirectories, you can do like this:
1802#
1803#   make foo/bar/baz.s
1804#
1805# The supported suffixes for single-target are listed in 'single-targets'
1806#
1807# To build only under specific subdirectories, you can do like this:
1808#
1809#   make foo/bar/baz/
1810
1811ifdef single-build
1812
1813# .ko is special because modpost is needed
1814single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1815single-no-ko := $(sort $(patsubst %.ko,%.mod, $(MAKECMDGOALS)))
1816
1817$(single-ko): single_modpost
1818	@:
1819$(single-no-ko): descend
1820	@:
1821
1822ifeq ($(KBUILD_EXTMOD),)
1823# For the single build of in-tree modules, use a temporary file to avoid
1824# the situation of modules_install installing an invalid modules.order.
1825MODORDER := .modules.tmp
1826endif
1827
1828PHONY += single_modpost
1829single_modpost: $(single-no-ko) modules_prepare
1830	$(Q){ $(foreach m, $(single-ko), echo $(extmod-prefix)$m;) } > $(MODORDER)
1831	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1832
1833KBUILD_MODULES := 1
1834
1835export KBUILD_SINGLE_TARGETS := $(addprefix $(extmod-prefix), $(single-no-ko))
1836
1837# trim unrelated directories
1838build-dirs := $(foreach d, $(build-dirs), \
1839			$(if $(filter $(d)/%, $(KBUILD_SINGLE_TARGETS)), $(d)))
1840
1841endif
1842
1843ifndef CONFIG_MODULES
1844KBUILD_MODULES :=
1845endif
1846
1847# Handle descending into subdirectories listed in $(build-dirs)
1848# Preset locale variables to speed up the build process. Limit locale
1849# tweaks to this spot to avoid wrong language settings when running
1850# make menuconfig etc.
1851# Error messages still appears in the original language
1852PHONY += descend $(build-dirs)
1853descend: $(build-dirs)
1854$(build-dirs): prepare
1855	$(Q)$(MAKE) $(build)=$@ \
1856	single-build=$(if $(filter-out $@/, $(filter $@/%, $(KBUILD_SINGLE_TARGETS))),1) \
1857	need-builtin=1 need-modorder=1
1858
1859clean-dirs := $(addprefix _clean_, $(clean-dirs))
1860PHONY += $(clean-dirs) clean
1861$(clean-dirs):
1862	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1863
1864clean: $(clean-dirs)
1865	$(call cmd,rmfiles)
1866	@find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1867		\( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1868		-o -name '*.ko.*' \
1869		-o -name '*.dtb' -o -name '*.dtbo' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1870		-o -name '*.dwo' -o -name '*.lst' \
1871		-o -name '*.su' -o -name '*.mod' \
1872		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1873		-o -name '*.lex.c' -o -name '*.tab.[ch]' \
1874		-o -name '*.asn1.[ch]' \
1875		-o -name '*.symtypes' -o -name 'modules.order' \
1876		-o -name '.tmp_*.o.*' \
1877		-o -name '*.c.[012]*.*' \
1878		-o -name '*.ll' \
1879		-o -name '*.gcno' \
1880		-o -name '*.*.symversions' \) -type f -print | xargs rm -f
1881
1882# Generate tags for editors
1883# ---------------------------------------------------------------------------
1884quiet_cmd_tags = GEN     $@
1885      cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1886
1887tags TAGS cscope gtags: FORCE
1888	$(call cmd,tags)
1889
1890# Script to generate missing namespace dependencies
1891# ---------------------------------------------------------------------------
1892
1893PHONY += nsdeps
1894nsdeps: export KBUILD_NSDEPS=1
1895nsdeps: modules
1896	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1897
1898# Clang Tooling
1899# ---------------------------------------------------------------------------
1900
1901quiet_cmd_gen_compile_commands = GEN     $@
1902      cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
1903
1904$(extmod-prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
1905	$(if $(KBUILD_EXTMOD),,$(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)) \
1906	$(if $(CONFIG_MODULES), $(MODORDER)) FORCE
1907	$(call if_changed,gen_compile_commands)
1908
1909targets += $(extmod-prefix)compile_commands.json
1910
1911PHONY += clang-tidy clang-analyzer
1912
1913ifdef CONFIG_CC_IS_CLANG
1914quiet_cmd_clang_tools = CHECK   $<
1915      cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
1916
1917clang-tidy clang-analyzer: $(extmod-prefix)compile_commands.json
1918	$(call cmd,clang_tools)
1919else
1920clang-tidy clang-analyzer:
1921	@echo "$@ requires CC=clang" >&2
1922	@false
1923endif
1924
1925# Scripts to check various things for consistency
1926# ---------------------------------------------------------------------------
1927
1928PHONY += includecheck versioncheck coccicheck export_report
1929
1930includecheck:
1931	find $(srctree)/* $(RCS_FIND_IGNORE) \
1932		-name '*.[hcS]' -type f -print | sort \
1933		| xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1934
1935versioncheck:
1936	find $(srctree)/* $(RCS_FIND_IGNORE) \
1937		-name '*.[hcS]' -type f -print | sort \
1938		| xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1939
1940coccicheck:
1941	$(Q)$(BASH) $(srctree)/scripts/$@
1942
1943export_report:
1944	$(PERL) $(srctree)/scripts/export_report.pl
1945
1946PHONY += checkstack kernelrelease kernelversion image_name
1947
1948# UML needs a little special treatment here.  It wants to use the host
1949# toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
1950# else wants $(ARCH), including people doing cross-builds, which means
1951# that $(SUBARCH) doesn't work here.
1952ifeq ($(ARCH), um)
1953CHECKSTACK_ARCH := $(SUBARCH)
1954else
1955CHECKSTACK_ARCH := $(ARCH)
1956endif
1957checkstack:
1958	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1959	$(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1960
1961kernelrelease:
1962	@echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1963
1964kernelversion:
1965	@echo $(KERNELVERSION)
1966
1967image_name:
1968	@echo $(KBUILD_IMAGE)
1969
1970# Clear a bunch of variables before executing the submake
1971
1972ifeq ($(quiet),silent_)
1973tools_silent=s
1974endif
1975
1976tools/: FORCE
1977	$(Q)mkdir -p $(objtree)/tools
1978	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1979
1980tools/%: FORCE
1981	$(Q)mkdir -p $(objtree)/tools
1982	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1983
1984quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
1985      cmd_rmfiles = rm -rf $(rm-files)
1986
1987# Run depmod only if we have System.map and depmod is executable
1988quiet_cmd_depmod = DEPMOD  $(KERNELRELEASE)
1989      cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1990                   $(KERNELRELEASE)
1991
1992# read saved command lines for existing targets
1993existing-targets := $(wildcard $(sort $(targets)))
1994
1995-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
1996
1997endif # config-build
1998endif # mixed-build
1999endif # need-sub-make
2000
2001PHONY += FORCE
2002FORCE:
2003
2004# Declare the contents of the PHONY variable as phony.  We keep that
2005# information in a variable so we can use it in if_changed and friends.
2006.PHONY: $(PHONY)
2007