xref: /linux/Makefile (revision b61442df748f06e98085fb604093a6215ce730eb)
1# SPDX-License-Identifier: GPL-2.0
2VERSION = 5
3PATCHLEVEL = 12
4SUBLEVEL = 0
5EXTRAVERSION = -rc3
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
267# Installation targets should not require compiler. Unfortunately, vdso_install
268# is an exception where build artifacts may be updated. This must be fixed.
269no-compiler-targets := $(no-dot-config-targets) install dtbs_install \
270			headers_install modules_install kernelrelease image_name
271no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease \
272			  image_name
273single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
274
275config-build	:=
276mixed-build	:=
277need-config	:= 1
278need-compiler	:= 1
279may-sync-config	:= 1
280single-build	:=
281
282ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
283	ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
284		need-config :=
285	endif
286endif
287
288ifneq ($(filter $(no-compiler-targets), $(MAKECMDGOALS)),)
289	ifeq ($(filter-out $(no-compiler-targets), $(MAKECMDGOALS)),)
290		need-compiler :=
291	endif
292endif
293
294ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
295	ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
296		may-sync-config :=
297	endif
298endif
299
300ifneq ($(KBUILD_EXTMOD),)
301	may-sync-config :=
302endif
303
304ifeq ($(KBUILD_EXTMOD),)
305        ifneq ($(filter %config,$(MAKECMDGOALS)),)
306		config-build := 1
307                ifneq ($(words $(MAKECMDGOALS)),1)
308			mixed-build := 1
309                endif
310        endif
311endif
312
313# We cannot build single targets and the others at the same time
314ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
315	single-build := 1
316	ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
317		mixed-build := 1
318	endif
319endif
320
321# For "make -j clean all", "make -j mrproper defconfig all", etc.
322ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
323        ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
324		mixed-build := 1
325        endif
326endif
327
328# install and modules_install need also be processed one by one
329ifneq ($(filter install,$(MAKECMDGOALS)),)
330        ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
331		mixed-build := 1
332        endif
333endif
334
335ifdef mixed-build
336# ===========================================================================
337# We're called with mixed targets (*config and build targets).
338# Handle them one by one.
339
340PHONY += $(MAKECMDGOALS) __build_one_by_one
341
342$(MAKECMDGOALS): __build_one_by_one
343	@:
344
345__build_one_by_one:
346	$(Q)set -e; \
347	for i in $(MAKECMDGOALS); do \
348		$(MAKE) -f $(srctree)/Makefile $$i; \
349	done
350
351else # !mixed-build
352
353include $(srctree)/scripts/Kbuild.include
354
355# Read KERNELRELEASE from include/config/kernel.release (if it exists)
356KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
357KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
358export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
359
360include $(srctree)/scripts/subarch.include
361
362# Cross compiling and selecting different set of gcc/bin-utils
363# ---------------------------------------------------------------------------
364#
365# When performing cross compilation for other architectures ARCH shall be set
366# to the target architecture. (See arch/* for the possibilities).
367# ARCH can be set during invocation of make:
368# make ARCH=ia64
369# Another way is to have ARCH set in the environment.
370# The default ARCH is the host where make is executed.
371
372# CROSS_COMPILE specify the prefix used for all executables used
373# during compilation. Only gcc and related bin-utils executables
374# are prefixed with $(CROSS_COMPILE).
375# CROSS_COMPILE can be set on the command line
376# make CROSS_COMPILE=ia64-linux-
377# Alternatively CROSS_COMPILE can be set in the environment.
378# Default value for CROSS_COMPILE is not to prefix executables
379# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
380ARCH		?= $(SUBARCH)
381
382# Architecture as present in compile.h
383UTS_MACHINE 	:= $(ARCH)
384SRCARCH 	:= $(ARCH)
385
386# Additional ARCH settings for x86
387ifeq ($(ARCH),i386)
388        SRCARCH := x86
389endif
390ifeq ($(ARCH),x86_64)
391        SRCARCH := x86
392endif
393
394# Additional ARCH settings for sparc
395ifeq ($(ARCH),sparc32)
396       SRCARCH := sparc
397endif
398ifeq ($(ARCH),sparc64)
399       SRCARCH := sparc
400endif
401
402# Additional ARCH settings for sh
403ifeq ($(ARCH),sh64)
404       SRCARCH := sh
405endif
406
407KCONFIG_CONFIG	?= .config
408export KCONFIG_CONFIG
409
410# Default file for 'make defconfig'. This may be overridden by arch-Makefile.
411export KBUILD_DEFCONFIG := defconfig
412
413# SHELL used by kbuild
414CONFIG_SHELL := sh
415
416HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
417HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
418HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
419
420ifneq ($(LLVM),)
421HOSTCC	= clang
422HOSTCXX	= clang++
423else
424HOSTCC	= gcc
425HOSTCXX	= g++
426endif
427
428export KBUILD_USERCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
429			      -O2 -fomit-frame-pointer -std=gnu89
430export KBUILD_USERLDFLAGS :=
431
432KBUILD_HOSTCFLAGS   := $(KBUILD_USERCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
433KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
434KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
435KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
436
437# Make variables (CC, etc...)
438CPP		= $(CC) -E
439ifneq ($(LLVM),)
440CC		= clang
441LD		= ld.lld
442AR		= llvm-ar
443NM		= llvm-nm
444OBJCOPY		= llvm-objcopy
445OBJDUMP		= llvm-objdump
446READELF		= llvm-readelf
447STRIP		= llvm-strip
448else
449CC		= $(CROSS_COMPILE)gcc
450LD		= $(CROSS_COMPILE)ld
451AR		= $(CROSS_COMPILE)ar
452NM		= $(CROSS_COMPILE)nm
453OBJCOPY		= $(CROSS_COMPILE)objcopy
454OBJDUMP		= $(CROSS_COMPILE)objdump
455READELF		= $(CROSS_COMPILE)readelf
456STRIP		= $(CROSS_COMPILE)strip
457endif
458PAHOLE		= pahole
459RESOLVE_BTFIDS	= $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
460LEX		= flex
461YACC		= bison
462AWK		= awk
463INSTALLKERNEL  := installkernel
464DEPMOD		= depmod
465PERL		= perl
466PYTHON3		= python3
467CHECK		= sparse
468BASH		= bash
469KGZIP		= gzip
470KBZIP2		= bzip2
471KLZOP		= lzop
472LZMA		= lzma
473LZ4		= lz4c
474XZ		= xz
475ZSTD		= zstd
476
477CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
478		  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
479NOSTDINC_FLAGS :=
480CFLAGS_MODULE   =
481AFLAGS_MODULE   =
482LDFLAGS_MODULE  =
483CFLAGS_KERNEL	=
484AFLAGS_KERNEL	=
485LDFLAGS_vmlinux =
486
487# Use USERINCLUDE when you must reference the UAPI directories only.
488USERINCLUDE    := \
489		-I$(srctree)/arch/$(SRCARCH)/include/uapi \
490		-I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
491		-I$(srctree)/include/uapi \
492		-I$(objtree)/include/generated/uapi \
493                -include $(srctree)/include/linux/compiler-version.h \
494                -include $(srctree)/include/linux/kconfig.h
495
496# Use LINUXINCLUDE when you must reference the include/ directory.
497# Needed to be compatible with the O= option
498LINUXINCLUDE    := \
499		-I$(srctree)/arch/$(SRCARCH)/include \
500		-I$(objtree)/arch/$(SRCARCH)/include/generated \
501		$(if $(building_out_of_srctree),-I$(srctree)/include) \
502		-I$(objtree)/include \
503		$(USERINCLUDE)
504
505KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
506KBUILD_CFLAGS   := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
507		   -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
508		   -Werror=implicit-function-declaration -Werror=implicit-int \
509		   -Werror=return-type -Wno-format-security \
510		   -std=gnu89
511KBUILD_CPPFLAGS := -D__KERNEL__
512KBUILD_AFLAGS_KERNEL :=
513KBUILD_CFLAGS_KERNEL :=
514KBUILD_AFLAGS_MODULE  := -DMODULE
515KBUILD_CFLAGS_MODULE  := -DMODULE
516KBUILD_LDFLAGS_MODULE :=
517KBUILD_LDFLAGS :=
518CLANG_FLAGS :=
519
520export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC
521export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
522export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
523export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
524export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
525
526export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
527export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
528export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
529export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
530export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
531
532# Files to ignore in find ... statements
533
534export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
535			  -name CVS -o -name .pc -o -name .hg -o -name .git \) \
536			  -prune -o
537export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
538			 --exclude CVS --exclude .pc --exclude .hg --exclude .git
539
540# ===========================================================================
541# Rules shared between *config targets and build targets
542
543# Basic helpers built in scripts/basic/
544PHONY += scripts_basic
545scripts_basic:
546	$(Q)$(MAKE) $(build)=scripts/basic
547	$(Q)rm -f .tmp_quiet_recordmcount
548
549PHONY += outputmakefile
550# Before starting out-of-tree build, make sure the source tree is clean.
551# outputmakefile generates a Makefile in the output directory, if using a
552# separate output directory. This allows convenient use of make in the
553# output directory.
554# At the same time when output Makefile generated, generate .gitignore to
555# ignore whole output directory
556outputmakefile:
557ifdef building_out_of_srctree
558	$(Q)if [ -f $(srctree)/.config -o \
559		 -d $(srctree)/include/config -o \
560		 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
561		echo >&2 "***"; \
562		echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
563		echo >&2 "*** in $(abs_srctree)";\
564		echo >&2 "***"; \
565		false; \
566	fi
567	$(Q)ln -fsn $(srctree) source
568	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile $(srctree)
569	$(Q)test -e .gitignore || \
570	{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
571endif
572
573# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
574# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
575# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
576# and from include/config/auto.conf.cmd to detect the compiler upgrade.
577CC_VERSION_TEXT = $(subst $(pound),,$(shell $(CC) --version 2>/dev/null | head -n 1))
578
579ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
580ifneq ($(CROSS_COMPILE),)
581CLANG_FLAGS	+= --target=$(notdir $(CROSS_COMPILE:%-=%))
582endif
583ifeq ($(LLVM_IAS),1)
584CLANG_FLAGS	+= -integrated-as
585else
586CLANG_FLAGS	+= -no-integrated-as
587GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
588CLANG_FLAGS	+= --prefix=$(GCC_TOOLCHAIN_DIR)$(notdir $(CROSS_COMPILE))
589endif
590CLANG_FLAGS	+= -Werror=unknown-warning-option
591KBUILD_CFLAGS	+= $(CLANG_FLAGS)
592KBUILD_AFLAGS	+= $(CLANG_FLAGS)
593export CLANG_FLAGS
594endif
595
596# Include this also for config targets because some architectures need
597# cc-cross-prefix to determine CROSS_COMPILE.
598ifdef need-compiler
599include $(srctree)/scripts/Makefile.compiler
600endif
601
602ifdef config-build
603# ===========================================================================
604# *config targets only - make sure prerequisites are updated, and descend
605# in scripts/kconfig to make the *config target
606
607# Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
608# KBUILD_DEFCONFIG may point out an alternative default configuration
609# used for 'make defconfig'
610include $(srctree)/arch/$(SRCARCH)/Makefile
611export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
612
613config: outputmakefile scripts_basic FORCE
614	$(Q)$(MAKE) $(build)=scripts/kconfig $@
615
616%config: outputmakefile scripts_basic FORCE
617	$(Q)$(MAKE) $(build)=scripts/kconfig $@
618
619else #!config-build
620# ===========================================================================
621# Build targets only - this includes vmlinux, arch specific targets, clean
622# targets and others. In general all targets except *config targets.
623
624# If building an external module we do not care about the all: rule
625# but instead __all depend on modules
626PHONY += all
627ifeq ($(KBUILD_EXTMOD),)
628__all: all
629else
630__all: modules
631endif
632
633# Decide whether to build built-in, modular, or both.
634# Normally, just do built-in.
635
636KBUILD_MODULES :=
637KBUILD_BUILTIN := 1
638
639# If we have only "make modules", don't compile built-in objects.
640ifeq ($(MAKECMDGOALS),modules)
641  KBUILD_BUILTIN :=
642endif
643
644# If we have "make <whatever> modules", compile modules
645# in addition to whatever we do anyway.
646# Just "make" or "make all" shall build modules as well
647
648ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
649  KBUILD_MODULES := 1
650endif
651
652ifeq ($(MAKECMDGOALS),)
653  KBUILD_MODULES := 1
654endif
655
656export KBUILD_MODULES KBUILD_BUILTIN
657
658ifdef need-config
659include include/config/auto.conf
660endif
661
662ifeq ($(KBUILD_EXTMOD),)
663# Objects we will link into vmlinux / subdirs we need to visit
664core-y		:= init/ usr/
665drivers-y	:= drivers/ sound/
666drivers-$(CONFIG_SAMPLES) += samples/
667drivers-$(CONFIG_NET) += net/
668drivers-y	+= virt/
669libs-y		:= lib/
670endif # KBUILD_EXTMOD
671
672# The all: target is the default when no target is given on the
673# command line.
674# This allow a user to issue only 'make' to build a kernel including modules
675# Defaults to vmlinux, but the arch makefile usually adds further targets
676all: vmlinux
677
678CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage \
679	$(call cc-option,-fno-tree-loop-im) \
680	$(call cc-disable-warning,maybe-uninitialized,)
681export CFLAGS_GCOV
682
683# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
684ifdef CONFIG_FUNCTION_TRACER
685  CC_FLAGS_FTRACE := -pg
686endif
687
688RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
689RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
690RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
691RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
692RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
693RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
694export RETPOLINE_CFLAGS
695export RETPOLINE_VDSO_CFLAGS
696
697include $(srctree)/arch/$(SRCARCH)/Makefile
698
699ifdef need-config
700ifdef may-sync-config
701# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
702# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
703# because some architectures define CROSS_COMPILE there.
704include include/config/auto.conf.cmd
705
706$(KCONFIG_CONFIG):
707	@echo >&2 '***'
708	@echo >&2 '*** Configuration file "$@" not found!'
709	@echo >&2 '***'
710	@echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
711	@echo >&2 '*** "make menuconfig" or "make xconfig").'
712	@echo >&2 '***'
713	@/bin/false
714
715# The actual configuration files used during the build are stored in
716# include/generated/ and include/config/. Update them if .config is newer than
717# include/config/auto.conf (which mirrors .config).
718#
719# This exploits the 'multi-target pattern rule' trick.
720# The syncconfig should be executed only once to make all the targets.
721# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
722quiet_cmd_syncconfig = SYNC    $@
723      cmd_syncconfig = $(MAKE) -f $(srctree)/Makefile syncconfig
724
725%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h: $(KCONFIG_CONFIG)
726	+$(call cmd,syncconfig)
727else # !may-sync-config
728# External modules and some install targets need include/generated/autoconf.h
729# and include/config/auto.conf but do not care if they are up-to-date.
730# Use auto.conf to trigger the test
731PHONY += include/config/auto.conf
732
733include/config/auto.conf:
734	$(Q)test -e include/generated/autoconf.h -a -e $@ || (		\
735	echo >&2;							\
736	echo >&2 "  ERROR: Kernel configuration is invalid.";		\
737	echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
738	echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";	\
739	echo >&2 ;							\
740	/bin/false)
741
742endif # may-sync-config
743endif # need-config
744
745KBUILD_CFLAGS	+= $(call cc-option,-fno-delete-null-pointer-checks,)
746KBUILD_CFLAGS	+= $(call cc-disable-warning,frame-address,)
747KBUILD_CFLAGS	+= $(call cc-disable-warning, format-truncation)
748KBUILD_CFLAGS	+= $(call cc-disable-warning, format-overflow)
749KBUILD_CFLAGS	+= $(call cc-disable-warning, address-of-packed-member)
750
751ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
752KBUILD_CFLAGS += -O2
753else ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3
754KBUILD_CFLAGS += -O3
755else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
756KBUILD_CFLAGS += -Os
757endif
758
759# Tell gcc to never replace conditional load with a non-conditional one
760KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
761KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
762
763ifdef CONFIG_READABLE_ASM
764# Disable optimizations that make assembler listings hard to read.
765# reorder blocks reorders the control in the function
766# ipa clone creates specialized cloned functions
767# partial inlining inlines only parts of functions
768KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
769                 $(call cc-option,-fno-ipa-cp-clone,) \
770                 $(call cc-option,-fno-partial-inlining)
771endif
772
773ifneq ($(CONFIG_FRAME_WARN),0)
774KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
775endif
776
777stackp-flags-y                                    := -fno-stack-protector
778stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
779stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
780
781KBUILD_CFLAGS += $(stackp-flags-y)
782
783ifdef CONFIG_CC_IS_CLANG
784KBUILD_CPPFLAGS += -Qunused-arguments
785KBUILD_CFLAGS += -Wno-format-invalid-specifier
786KBUILD_CFLAGS += -Wno-gnu
787# CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
788# source of a reference will be _MergedGlobals and not on of the whitelisted names.
789# See modpost pattern 2
790KBUILD_CFLAGS += -mno-global-merge
791else
792
793# These warnings generated too much noise in a regular build.
794# Use make W=1 to enable them (see scripts/Makefile.extrawarn)
795KBUILD_CFLAGS += -Wno-unused-but-set-variable
796
797# Warn about unmarked fall-throughs in switch statement.
798# Disabled for clang while comment to attribute conversion happens and
799# https://github.com/ClangBuiltLinux/linux/issues/636 is discussed.
800KBUILD_CFLAGS += $(call cc-option,-Wimplicit-fallthrough,)
801endif
802
803KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
804ifdef CONFIG_FRAME_POINTER
805KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
806else
807# Some targets (ARM with Thumb2, for example), can't be built with frame
808# pointers.  For those, we don't have FUNCTION_TRACER automatically
809# select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
810# incompatible with -fomit-frame-pointer with current GCC, so we don't use
811# -fomit-frame-pointer with FUNCTION_TRACER.
812ifndef CONFIG_FUNCTION_TRACER
813KBUILD_CFLAGS	+= -fomit-frame-pointer
814endif
815endif
816
817# Initialize all stack variables with a 0xAA pattern.
818ifdef CONFIG_INIT_STACK_ALL_PATTERN
819KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
820endif
821
822# Initialize all stack variables with a zero value.
823ifdef CONFIG_INIT_STACK_ALL_ZERO
824# Future support for zero initialization is still being debated, see
825# https://bugs.llvm.org/show_bug.cgi?id=45497. These flags are subject to being
826# renamed or dropped.
827KBUILD_CFLAGS	+= -ftrivial-auto-var-init=zero
828KBUILD_CFLAGS	+= -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
829endif
830
831DEBUG_CFLAGS	:=
832
833# Workaround for GCC versions < 5.0
834# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61801
835ifdef CONFIG_CC_IS_GCC
836DEBUG_CFLAGS	+= $(call cc-ifversion, -lt, 0500, $(call cc-option, -fno-var-tracking-assignments))
837endif
838
839ifdef CONFIG_DEBUG_INFO
840
841ifdef CONFIG_DEBUG_INFO_SPLIT
842DEBUG_CFLAGS	+= -gsplit-dwarf
843else
844DEBUG_CFLAGS	+= -g
845endif
846
847ifneq ($(LLVM_IAS),1)
848KBUILD_AFLAGS	+= -Wa,-gdwarf-2
849endif
850
851ifndef CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT
852dwarf-version-$(CONFIG_DEBUG_INFO_DWARF4) := 4
853dwarf-version-$(CONFIG_DEBUG_INFO_DWARF5) := 5
854DEBUG_CFLAGS	+= -gdwarf-$(dwarf-version-y)
855endif
856
857ifdef CONFIG_DEBUG_INFO_REDUCED
858DEBUG_CFLAGS	+= $(call cc-option, -femit-struct-debug-baseonly) \
859		   $(call cc-option,-fno-var-tracking)
860endif
861
862ifdef CONFIG_DEBUG_INFO_COMPRESSED
863DEBUG_CFLAGS	+= -gz=zlib
864KBUILD_AFLAGS	+= -gz=zlib
865KBUILD_LDFLAGS	+= --compress-debug-sections=zlib
866endif
867
868endif # CONFIG_DEBUG_INFO
869
870KBUILD_CFLAGS += $(DEBUG_CFLAGS)
871export DEBUG_CFLAGS
872
873ifdef CONFIG_FUNCTION_TRACER
874ifdef CONFIG_FTRACE_MCOUNT_USE_CC
875  CC_FLAGS_FTRACE	+= -mrecord-mcount
876  ifdef CONFIG_HAVE_NOP_MCOUNT
877    ifeq ($(call cc-option-yn, -mnop-mcount),y)
878      CC_FLAGS_FTRACE	+= -mnop-mcount
879      CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
880    endif
881  endif
882endif
883ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
884  CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
885endif
886ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
887  ifdef CONFIG_HAVE_C_RECORDMCOUNT
888    BUILD_C_RECORDMCOUNT := y
889    export BUILD_C_RECORDMCOUNT
890  endif
891endif
892ifdef CONFIG_HAVE_FENTRY
893  ifeq ($(call cc-option-yn, -mfentry),y)
894    CC_FLAGS_FTRACE	+= -mfentry
895    CC_FLAGS_USING	+= -DCC_USING_FENTRY
896  endif
897endif
898export CC_FLAGS_FTRACE
899KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
900KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
901endif
902
903# We trigger additional mismatches with less inlining
904ifdef CONFIG_DEBUG_SECTION_MISMATCH
905KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
906endif
907
908ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
909KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
910LDFLAGS_vmlinux += --gc-sections
911endif
912
913ifdef CONFIG_SHADOW_CALL_STACK
914CC_FLAGS_SCS	:= -fsanitize=shadow-call-stack
915KBUILD_CFLAGS	+= $(CC_FLAGS_SCS)
916export CC_FLAGS_SCS
917endif
918
919ifdef CONFIG_LTO_CLANG
920ifdef CONFIG_LTO_CLANG_THIN
921CC_FLAGS_LTO	:= -flto=thin -fsplit-lto-unit
922KBUILD_LDFLAGS	+= --thinlto-cache-dir=$(extmod_prefix).thinlto-cache
923else
924CC_FLAGS_LTO	:= -flto
925endif
926CC_FLAGS_LTO	+= -fvisibility=hidden
927
928# Limit inlining across translation units to reduce binary size
929KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
930endif
931
932ifdef CONFIG_LTO
933KBUILD_CFLAGS	+= -fno-lto $(CC_FLAGS_LTO)
934KBUILD_AFLAGS	+= -fno-lto
935export CC_FLAGS_LTO
936endif
937
938ifdef CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_32B
939KBUILD_CFLAGS += -falign-functions=32
940endif
941
942# arch Makefile may override CC so keep this after arch Makefile is included
943NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
944
945# warn about C99 declaration after statement
946KBUILD_CFLAGS += -Wdeclaration-after-statement
947
948# Variable Length Arrays (VLAs) should not be used anywhere in the kernel
949KBUILD_CFLAGS += -Wvla
950
951# disable pointer signed / unsigned warnings in gcc 4.0
952KBUILD_CFLAGS += -Wno-pointer-sign
953
954# disable stringop warnings in gcc 8+
955KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
956
957# We'll want to enable this eventually, but it's not going away for 5.7 at least
958KBUILD_CFLAGS += $(call cc-disable-warning, zero-length-bounds)
959KBUILD_CFLAGS += $(call cc-disable-warning, array-bounds)
960KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
961
962# Another good warning that we'll want to enable eventually
963KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
964
965# Enabled with W=2, disabled by default as noisy
966KBUILD_CFLAGS += $(call cc-disable-warning, maybe-uninitialized)
967
968# disable invalid "can't wrap" optimizations for signed / pointers
969KBUILD_CFLAGS	+= -fno-strict-overflow
970
971# Make sure -fstack-check isn't enabled (like gentoo apparently did)
972KBUILD_CFLAGS  += -fno-stack-check
973
974# conserve stack if available
975KBUILD_CFLAGS   += $(call cc-option,-fconserve-stack)
976
977# Prohibit date/time macros, which would make the build non-deterministic
978KBUILD_CFLAGS   += -Werror=date-time
979
980# enforce correct pointer usage
981KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)
982
983# Require designated initializers for all marked structures
984KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)
985
986# change __FILE__ to the relative path from the srctree
987KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
988
989# include additional Makefiles when needed
990include-y			:= scripts/Makefile.extrawarn
991include-$(CONFIG_KASAN)		+= scripts/Makefile.kasan
992include-$(CONFIG_KCSAN)		+= scripts/Makefile.kcsan
993include-$(CONFIG_UBSAN)		+= scripts/Makefile.ubsan
994include-$(CONFIG_KCOV)		+= scripts/Makefile.kcov
995include-$(CONFIG_GCC_PLUGINS)	+= scripts/Makefile.gcc-plugins
996
997include $(addprefix $(srctree)/, $(include-y))
998
999# scripts/Makefile.gcc-plugins is intentionally included last.
1000# Do not add $(call cc-option,...) below this line. When you build the kernel
1001# from the clean source tree, the GCC plugins do not exist at this point.
1002
1003# Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
1004KBUILD_CPPFLAGS += $(KCPPFLAGS)
1005KBUILD_AFLAGS   += $(KAFLAGS)
1006KBUILD_CFLAGS   += $(KCFLAGS)
1007
1008KBUILD_LDFLAGS_MODULE += --build-id=sha1
1009LDFLAGS_vmlinux += --build-id=sha1
1010
1011ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1012LDFLAGS_vmlinux	+= $(call ld-option, -X,)
1013endif
1014
1015ifeq ($(CONFIG_RELR),y)
1016LDFLAGS_vmlinux	+= --pack-dyn-relocs=relr
1017endif
1018
1019# We never want expected sections to be placed heuristically by the
1020# linker. All sections should be explicitly named in the linker script.
1021ifdef CONFIG_LD_ORPHAN_WARN
1022LDFLAGS_vmlinux += --orphan-handling=warn
1023endif
1024
1025# Align the bit size of userspace programs with the kernel
1026KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1027KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1028
1029# make the checker run with the right architecture
1030CHECKFLAGS += --arch=$(ARCH)
1031
1032# insure the checker run with the right endianness
1033CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1034
1035# the checker needs the correct machine size
1036CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1037
1038# Default kernel image to build when no specific target is given.
1039# KBUILD_IMAGE may be overruled on the command line or
1040# set in the environment
1041# Also any assignments in arch/$(ARCH)/Makefile take precedence over
1042# this default value
1043export KBUILD_IMAGE ?= vmlinux
1044
1045#
1046# INSTALL_PATH specifies where to place the updated kernel and system map
1047# images. Default is /boot, but you can set it to other values
1048export	INSTALL_PATH ?= /boot
1049
1050#
1051# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1052# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1053# an argument if needed. Otherwise it defaults to the kernel install path
1054#
1055export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1056
1057#
1058# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1059# relocations required by build roots.  This is not defined in the
1060# makefile but the argument can be passed to make if needed.
1061#
1062
1063MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1064export MODLIB
1065
1066HOST_LIBELF_LIBS = $(shell pkg-config libelf --libs 2>/dev/null || echo -lelf)
1067
1068has_libelf = $(call try-run,\
1069               echo "int main() {}" | $(HOSTCC) -xc -o /dev/null $(HOST_LIBELF_LIBS) -,1,0)
1070
1071ifdef CONFIG_STACK_VALIDATION
1072  ifeq ($(has_libelf),1)
1073    objtool_target := tools/objtool FORCE
1074  else
1075    SKIP_STACK_VALIDATION := 1
1076    export SKIP_STACK_VALIDATION
1077  endif
1078endif
1079
1080PHONY += resolve_btfids_clean
1081
1082resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1083
1084# tools/bpf/resolve_btfids directory might not exist
1085# in output directory, skip its clean in that case
1086resolve_btfids_clean:
1087ifneq ($(wildcard $(resolve_btfids_O)),)
1088	$(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1089endif
1090
1091ifdef CONFIG_BPF
1092ifdef CONFIG_DEBUG_INFO_BTF
1093  ifeq ($(has_libelf),1)
1094    resolve_btfids_target := tools/bpf/resolve_btfids FORCE
1095  else
1096    ERROR_RESOLVE_BTFIDS := 1
1097  endif
1098endif # CONFIG_DEBUG_INFO_BTF
1099endif # CONFIG_BPF
1100
1101PHONY += prepare0
1102
1103export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
1104export MODORDER := $(extmod_prefix)modules.order
1105export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
1106
1107ifeq ($(KBUILD_EXTMOD),)
1108core-y		+= kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
1109
1110vmlinux-dirs	:= $(patsubst %/,%,$(filter %/, \
1111		     $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
1112		     $(libs-y) $(libs-m)))
1113
1114vmlinux-alldirs	:= $(sort $(vmlinux-dirs) Documentation \
1115		     $(patsubst %/,%,$(filter %/, $(core-) \
1116			$(drivers-) $(libs-))))
1117
1118subdir-modorder := $(addsuffix modules.order,$(filter %/, \
1119			$(core-y) $(core-m) $(libs-y) $(libs-m) \
1120			$(drivers-y) $(drivers-m)))
1121
1122build-dirs	:= $(vmlinux-dirs)
1123clean-dirs	:= $(vmlinux-alldirs)
1124
1125# Externally visible symbols (used by link-vmlinux.sh)
1126KBUILD_VMLINUX_OBJS := $(head-y) $(patsubst %/,%/built-in.a, $(core-y))
1127KBUILD_VMLINUX_OBJS += $(addsuffix built-in.a, $(filter %/, $(libs-y)))
1128ifdef CONFIG_MODULES
1129KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1130KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1131else
1132KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1133endif
1134KBUILD_VMLINUX_OBJS += $(patsubst %/,%/built-in.a, $(drivers-y))
1135
1136export KBUILD_VMLINUX_OBJS KBUILD_VMLINUX_LIBS
1137export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1138# used by scripts/Makefile.package
1139export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) LICENSES arch include scripts tools)
1140
1141vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
1142
1143# Recurse until adjust_autoksyms.sh is satisfied
1144PHONY += autoksyms_recursive
1145ifdef CONFIG_TRIM_UNUSED_KSYMS
1146# For the kernel to actually contain only the needed exported symbols,
1147# we have to build modules as well to determine what those symbols are.
1148# (this can be evaluated only once include/config/auto.conf has been included)
1149KBUILD_MODULES := 1
1150
1151autoksyms_recursive: descend modules.order
1152	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1153	  "$(MAKE) -f $(srctree)/Makefile vmlinux"
1154endif
1155
1156autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1157
1158quiet_cmd_autoksyms_h = GEN     $@
1159      cmd_autoksyms_h = mkdir -p $(dir $@); \
1160			$(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@
1161
1162$(autoksyms_h):
1163	$(call cmd,autoksyms_h)
1164
1165ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1166
1167# Final link of vmlinux with optional arch pass after final link
1168cmd_link-vmlinux =                                                 \
1169	$(CONFIG_SHELL) $< "$(LD)" "$(KBUILD_LDFLAGS)" "$(LDFLAGS_vmlinux)";    \
1170	$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1171
1172vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1173	+$(call if_changed_dep,link-vmlinux)
1174
1175targets := vmlinux
1176
1177# The actual objects are generated when descending,
1178# make sure no implicit rule kicks in
1179$(sort $(vmlinux-deps) $(subdir-modorder)): descend ;
1180
1181filechk_kernel.release = \
1182	echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1183
1184# Store (new) KERNELRELEASE string in include/config/kernel.release
1185include/config/kernel.release: FORCE
1186	$(call filechk,kernel.release)
1187
1188# Additional helpers built in scripts/
1189# Carefully list dependencies so we do not try to build scripts twice
1190# in parallel
1191PHONY += scripts
1192scripts: scripts_basic scripts_dtc
1193	$(Q)$(MAKE) $(build)=$(@)
1194
1195# Things we need to do before we recursively start building the kernel
1196# or the modules are listed in "prepare".
1197# A multi level approach is used. prepareN is processed before prepareN-1.
1198# archprepare is used in arch Makefiles and when processed asm symlink,
1199# version.h and scripts_basic is processed / created.
1200
1201PHONY += prepare archprepare
1202
1203archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1204	asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h \
1205	include/generated/autoconf.h
1206
1207prepare0: archprepare
1208	$(Q)$(MAKE) $(build)=scripts/mod
1209	$(Q)$(MAKE) $(build)=.
1210
1211# All the preparing..
1212prepare: prepare0 prepare-objtool prepare-resolve_btfids
1213
1214# Support for using generic headers in asm-generic
1215asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1216
1217PHONY += asm-generic uapi-asm-generic
1218asm-generic: uapi-asm-generic
1219	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1220	generic=include/asm-generic
1221uapi-asm-generic:
1222	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1223	generic=include/uapi/asm-generic
1224
1225PHONY += prepare-objtool prepare-resolve_btfids
1226prepare-objtool: $(objtool_target)
1227ifeq ($(SKIP_STACK_VALIDATION),1)
1228ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
1229	@echo "error: Cannot generate __mcount_loc for CONFIG_DYNAMIC_FTRACE=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1230	@false
1231endif
1232ifdef CONFIG_UNWINDER_ORC
1233	@echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1234	@false
1235else
1236	@echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1237endif
1238endif
1239
1240prepare-resolve_btfids: $(resolve_btfids_target)
1241ifeq ($(ERROR_RESOLVE_BTFIDS),1)
1242	@echo "error: Cannot resolve BTF IDs for CONFIG_DEBUG_INFO_BTF, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1243	@false
1244endif
1245# Generate some files
1246# ---------------------------------------------------------------------------
1247
1248# KERNELRELEASE can change from a few different places, meaning version.h
1249# needs to be updated, so this check is forced on all builds
1250
1251uts_len := 64
1252define filechk_utsrelease.h
1253	if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1254	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1255	  exit 1;                                                         \
1256	fi;                                                               \
1257	echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1258endef
1259
1260define filechk_version.h
1261	if [ $(SUBLEVEL) -gt 255 ]; then                                 \
1262		echo \#define LINUX_VERSION_CODE $(shell                 \
1263		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1264	else                                                             \
1265		echo \#define LINUX_VERSION_CODE $(shell                 \
1266		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1267	fi;                                                              \
1268	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
1269	((c) > 255 ? 255 : (c)))';                                       \
1270	echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
1271	echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
1272	echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1273endef
1274
1275$(version_h): PATCHLEVEL := $(if $(PATCHLEVEL), $(PATCHLEVEL), 0)
1276$(version_h): SUBLEVEL := $(if $(SUBLEVEL), $(SUBLEVEL), 0)
1277$(version_h): FORCE
1278	$(call filechk,version.h)
1279
1280include/generated/utsrelease.h: include/config/kernel.release FORCE
1281	$(call filechk,utsrelease.h)
1282
1283PHONY += headerdep
1284headerdep:
1285	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1286	$(srctree)/scripts/headerdep.pl -I$(srctree)/include
1287
1288# ---------------------------------------------------------------------------
1289# Kernel headers
1290
1291#Default location for installed headers
1292export INSTALL_HDR_PATH = $(objtree)/usr
1293
1294quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1295      cmd_headers_install = \
1296	mkdir -p $(INSTALL_HDR_PATH); \
1297	rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1298	usr/include $(INSTALL_HDR_PATH)
1299
1300PHONY += headers_install
1301headers_install: headers
1302	$(call cmd,headers_install)
1303
1304PHONY += archheaders archscripts
1305
1306hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1307
1308PHONY += headers
1309headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1310	$(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1311	  $(error Headers not exportable for the $(SRCARCH) architecture))
1312	$(Q)$(MAKE) $(hdr-inst)=include/uapi
1313	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1314
1315# Deprecated. It is no-op now.
1316PHONY += headers_check
1317headers_check:
1318	@echo >&2 "=================== WARNING ==================="
1319	@echo >&2 "Since Linux 5.5, 'make headers_check' is no-op,"
1320	@echo >&2 "and will be removed after Linux 5.15 release."
1321	@echo >&2 "Please remove headers_check from your scripts."
1322	@echo >&2 "==============================================="
1323
1324ifdef CONFIG_HEADERS_INSTALL
1325prepare: headers
1326endif
1327
1328PHONY += scripts_unifdef
1329scripts_unifdef: scripts_basic
1330	$(Q)$(MAKE) $(build)=scripts scripts/unifdef
1331
1332# ---------------------------------------------------------------------------
1333# Kernel selftest
1334
1335PHONY += kselftest
1336kselftest:
1337	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1338
1339kselftest-%: FORCE
1340	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1341
1342PHONY += kselftest-merge
1343kselftest-merge:
1344	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1345	$(Q)find $(srctree)/tools/testing/selftests -name config | \
1346		xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1347	$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1348
1349# ---------------------------------------------------------------------------
1350# Devicetree files
1351
1352ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1353dtstree := arch/$(SRCARCH)/boot/dts
1354endif
1355
1356ifneq ($(dtstree),)
1357
1358%.dtb: include/config/kernel.release scripts_dtc
1359	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1360
1361%.dtbo: include/config/kernel.release scripts_dtc
1362	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1363
1364PHONY += dtbs dtbs_install dtbs_check
1365dtbs: include/config/kernel.release scripts_dtc
1366	$(Q)$(MAKE) $(build)=$(dtstree)
1367
1368ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1369export CHECK_DTBS=y
1370dtbs: dt_binding_check
1371endif
1372
1373dtbs_check: dtbs
1374
1375dtbs_install:
1376	$(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1377
1378ifdef CONFIG_OF_EARLY_FLATTREE
1379all: dtbs
1380endif
1381
1382endif
1383
1384PHONY += scripts_dtc
1385scripts_dtc: scripts_basic
1386	$(Q)$(MAKE) $(build)=scripts/dtc
1387
1388ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1389export CHECK_DT_BINDING=y
1390endif
1391
1392PHONY += dt_binding_check
1393dt_binding_check: scripts_dtc
1394	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1395
1396# ---------------------------------------------------------------------------
1397# Modules
1398
1399ifdef CONFIG_MODULES
1400
1401# By default, build modules as well
1402
1403all: modules
1404
1405# When we're building modules with modversions, we need to consider
1406# the built-in objects during the descend as well, in order to
1407# make sure the checksums are up to date before we record them.
1408ifdef CONFIG_MODVERSIONS
1409  KBUILD_BUILTIN := 1
1410endif
1411
1412# Build modules
1413#
1414# A module can be listed more than once in obj-m resulting in
1415# duplicate lines in modules.order files.  Those are removed
1416# using awk while concatenating to the final file.
1417
1418PHONY += modules
1419modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_check modules_prepare
1420
1421cmd_modules_order = $(AWK) '!x[$$0]++' $(real-prereqs) > $@
1422
1423modules.order: $(subdir-modorder) FORCE
1424	$(call if_changed,modules_order)
1425
1426targets += modules.order
1427
1428# Target to prepare building external modules
1429PHONY += modules_prepare
1430modules_prepare: prepare
1431	$(Q)$(MAKE) $(build)=scripts scripts/module.lds
1432
1433export modules_sign_only :=
1434
1435ifeq ($(CONFIG_MODULE_SIG),y)
1436PHONY += modules_sign
1437modules_sign: modules_install
1438	@:
1439
1440# modules_sign is a subset of modules_install.
1441# 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1442ifeq ($(filter modules_install,$(MAKECMDGOALS)),)
1443modules_sign_only := y
1444endif
1445endif
1446
1447modinst_pre :=
1448ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
1449modinst_pre := __modinst_pre
1450endif
1451
1452modules_install: $(modinst_pre)
1453PHONY += __modinst_pre
1454__modinst_pre:
1455	@rm -rf $(MODLIB)/kernel
1456	@rm -f $(MODLIB)/source
1457	@mkdir -p $(MODLIB)/kernel
1458	@ln -s $(abspath $(srctree)) $(MODLIB)/source
1459	@if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
1460		rm -f $(MODLIB)/build ; \
1461		ln -s $(CURDIR) $(MODLIB)/build ; \
1462	fi
1463	@sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order
1464	@cp -f modules.builtin $(MODLIB)/
1465	@cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
1466
1467endif # CONFIG_MODULES
1468
1469###
1470# Cleaning is done on three levels.
1471# make clean     Delete most generated files
1472#                Leave enough to build external modules
1473# make mrproper  Delete the current configuration, and all generated files
1474# make distclean Remove editor backup files, patch leftover files and the like
1475
1476# Directories & files removed with 'make clean'
1477CLEAN_FILES += include/ksym vmlinux.symvers modules-only.symvers \
1478	       modules.builtin modules.builtin.modinfo modules.nsdeps \
1479	       compile_commands.json .thinlto-cache
1480
1481# Directories & files removed with 'make mrproper'
1482MRPROPER_FILES += include/config include/generated          \
1483		  arch/$(SRCARCH)/include/generated .tmp_objdiff \
1484		  debian snap tar-install \
1485		  .config .config.old .version \
1486		  Module.symvers \
1487		  signing_key.pem signing_key.priv signing_key.x509	\
1488		  x509.genkey extra_certificates signing_key.x509.keyid	\
1489		  signing_key.x509.signer vmlinux-gdb.py \
1490		  *.spec
1491
1492# Directories & files removed with 'make distclean'
1493DISTCLEAN_FILES += tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS
1494
1495# clean - Delete most, but leave enough to build external modules
1496#
1497clean: rm-files := $(CLEAN_FILES)
1498
1499PHONY += archclean vmlinuxclean
1500
1501vmlinuxclean:
1502	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1503	$(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1504
1505clean: archclean vmlinuxclean resolve_btfids_clean
1506
1507# mrproper - Delete all generated files, including .config
1508#
1509mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1510mrproper-dirs      := $(addprefix _mrproper_,scripts)
1511
1512PHONY += $(mrproper-dirs) mrproper
1513$(mrproper-dirs):
1514	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1515
1516mrproper: clean $(mrproper-dirs)
1517	$(call cmd,rmfiles)
1518
1519# distclean
1520#
1521distclean: rm-files := $(wildcard $(DISTCLEAN_FILES))
1522
1523PHONY += distclean
1524
1525distclean: mrproper
1526	$(call cmd,rmfiles)
1527	@find $(srctree) $(RCS_FIND_IGNORE) \
1528		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1529		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
1530		-o -name 'core' \) \
1531		-type f -print | xargs rm -f
1532
1533
1534# Packaging of the kernel to various formats
1535# ---------------------------------------------------------------------------
1536
1537%src-pkg: FORCE
1538	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1539%pkg: include/config/kernel.release FORCE
1540	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1541
1542# Brief documentation of the typical targets used
1543# ---------------------------------------------------------------------------
1544
1545boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1546boards := $(sort $(notdir $(boards)))
1547board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1548board-dirs := $(sort $(notdir $(board-dirs:/=)))
1549
1550PHONY += help
1551help:
1552	@echo  'Cleaning targets:'
1553	@echo  '  clean		  - Remove most generated files but keep the config and'
1554	@echo  '                    enough build support to build external modules'
1555	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
1556	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
1557	@echo  ''
1558	@echo  'Configuration targets:'
1559	@$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1560	@echo  ''
1561	@echo  'Other generic targets:'
1562	@echo  '  all		  - Build all targets marked with [*]'
1563	@echo  '* vmlinux	  - Build the bare kernel'
1564	@echo  '* modules	  - Build all modules'
1565	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1566	@echo  '  dir/            - Build all files in dir and below'
1567	@echo  '  dir/file.[ois]  - Build specified target only'
1568	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1569	@echo  '                    (requires compiler support for LLVM assembly generation)'
1570	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1571	@echo  '                    (requires a recent binutils and recent build (System.map))'
1572	@echo  '  dir/file.ko     - Build module including final link'
1573	@echo  '  modules_prepare - Set up for building external modules'
1574	@echo  '  tags/TAGS	  - Generate tags file for editors'
1575	@echo  '  cscope	  - Generate cscope index'
1576	@echo  '  gtags           - Generate GNU GLOBAL index'
1577	@echo  '  kernelrelease	  - Output the release version string (use with make -s)'
1578	@echo  '  kernelversion	  - Output the version stored in Makefile (use with make -s)'
1579	@echo  '  image_name	  - Output the image name (use with make -s)'
1580	@echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1581	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1582	 echo  ''
1583	@echo  'Static analysers:'
1584	@echo  '  checkstack      - Generate a list of stack hogs'
1585	@echo  '  versioncheck    - Sanity check on version.h usage'
1586	@echo  '  includecheck    - Check for duplicate included header files'
1587	@echo  '  export_report   - List the usages of all exported symbols'
1588	@echo  '  headerdep       - Detect inclusion cycles in headers'
1589	@echo  '  coccicheck      - Check with Coccinelle'
1590	@echo  '  clang-analyzer  - Check with clang static analyzer'
1591	@echo  '  clang-tidy      - Check with clang-tidy'
1592	@echo  ''
1593	@echo  'Tools:'
1594	@echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1595	@echo  ''
1596	@echo  'Kernel selftest:'
1597	@echo  '  kselftest         - Build and run kernel selftest'
1598	@echo  '                      Build, install, and boot kernel before'
1599	@echo  '                      running kselftest on it'
1600	@echo  '                      Run as root for full coverage'
1601	@echo  '  kselftest-all     - Build kernel selftest'
1602	@echo  '  kselftest-install - Build and install kernel selftest'
1603	@echo  '  kselftest-clean   - Remove all generated kselftest files'
1604	@echo  '  kselftest-merge   - Merge all the config dependencies of'
1605	@echo  '		      kselftest to existing .config.'
1606	@echo  ''
1607	@$(if $(dtstree), \
1608		echo 'Devicetree:'; \
1609		echo '* dtbs             - Build device tree blobs for enabled boards'; \
1610		echo '  dtbs_install     - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1611		echo '  dt_binding_check - Validate device tree binding documents'; \
1612		echo '  dtbs_check       - Validate device tree source files';\
1613		echo '')
1614
1615	@echo 'Userspace tools targets:'
1616	@echo '  use "make tools/help"'
1617	@echo '  or  "cd tools; make help"'
1618	@echo  ''
1619	@echo  'Kernel packaging:'
1620	@$(MAKE) -f $(srctree)/scripts/Makefile.package help
1621	@echo  ''
1622	@echo  'Documentation targets:'
1623	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1624	@echo  ''
1625	@echo  'Architecture specific targets ($(SRCARCH)):'
1626	@$(if $(archhelp),$(archhelp),\
1627		echo '  No architecture specific help defined for $(SRCARCH)')
1628	@echo  ''
1629	@$(if $(boards), \
1630		$(foreach b, $(boards), \
1631		printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1632		echo '')
1633	@$(if $(board-dirs), \
1634		$(foreach b, $(board-dirs), \
1635		printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1636		printf "  %-16s - Show all of the above\\n" help-boards; \
1637		echo '')
1638
1639	@echo  '  make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1640	@echo  '  make V=2   [targets] 2 => give reason for rebuild of target'
1641	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1642	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1643	@echo  '                       (sparse by default)'
1644	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1645	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1646	@echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
1647	@echo  '		1: warnings which may be relevant and do not occur too often'
1648	@echo  '		2: warnings which occur quite often but may still be relevant'
1649	@echo  '		3: more obscure warnings, can most likely be ignored'
1650	@echo  '		Multiple levels can be combined with W=12 or W=123'
1651	@echo  ''
1652	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
1653	@echo  'For further info see the ./README file'
1654
1655
1656help-board-dirs := $(addprefix help-,$(board-dirs))
1657
1658help-boards: $(help-board-dirs)
1659
1660boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1661
1662$(help-board-dirs): help-%:
1663	@echo  'Architecture specific targets ($(SRCARCH) $*):'
1664	@$(if $(boards-per-dir), \
1665		$(foreach b, $(boards-per-dir), \
1666		printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1667		echo '')
1668
1669
1670# Documentation targets
1671# ---------------------------------------------------------------------------
1672DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1673	       linkcheckdocs dochelp refcheckdocs
1674PHONY += $(DOC_TARGETS)
1675$(DOC_TARGETS):
1676	$(Q)$(MAKE) $(build)=Documentation $@
1677
1678# Misc
1679# ---------------------------------------------------------------------------
1680
1681PHONY += scripts_gdb
1682scripts_gdb: prepare0
1683	$(Q)$(MAKE) $(build)=scripts/gdb
1684	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1685
1686ifdef CONFIG_GDB_SCRIPTS
1687all: scripts_gdb
1688endif
1689
1690else # KBUILD_EXTMOD
1691
1692###
1693# External module support.
1694# When building external modules the kernel used as basis is considered
1695# read-only, and no consistency checks are made and the make
1696# system is not used on the basis kernel. If updates are required
1697# in the basis kernel ordinary make commands (without M=...) must
1698# be used.
1699#
1700# The following are the only valid targets when building external
1701# modules.
1702# make M=dir clean     Delete all automatically generated files
1703# make M=dir modules   Make all modules in specified dir
1704# make M=dir	       Same as 'make M=dir modules'
1705# make M=dir modules_install
1706#                      Install the modules built in the module directory
1707#                      Assumes install directory is already created
1708
1709# We are always building only modules.
1710KBUILD_BUILTIN :=
1711KBUILD_MODULES := 1
1712
1713build-dirs := $(KBUILD_EXTMOD)
1714$(MODORDER): descend
1715	@:
1716
1717compile_commands.json: $(extmod_prefix)compile_commands.json
1718PHONY += compile_commands.json
1719
1720clean-dirs := $(KBUILD_EXTMOD)
1721clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1722	$(KBUILD_EXTMOD)/compile_commands.json $(KBUILD_EXTMOD)/.thinlto-cache
1723
1724PHONY += help
1725help:
1726	@echo  '  Building external modules.'
1727	@echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1728	@echo  ''
1729	@echo  '  modules         - default target, build the module(s)'
1730	@echo  '  modules_install - install the module'
1731	@echo  '  clean           - remove generated files in module directory only'
1732	@echo  ''
1733
1734# no-op for external module builds
1735PHONY += prepare modules_prepare
1736
1737endif # KBUILD_EXTMOD
1738
1739# ---------------------------------------------------------------------------
1740# Modules
1741
1742PHONY += modules modules_install
1743
1744ifdef CONFIG_MODULES
1745
1746modules: modules_check
1747	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1748
1749PHONY += modules_check
1750modules_check: $(MODORDER)
1751	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1752
1753quiet_cmd_depmod = DEPMOD  $(MODLIB)
1754      cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1755                   $(KERNELRELEASE)
1756
1757modules_install:
1758	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1759	$(call cmd,depmod)
1760
1761else # CONFIG_MODULES
1762
1763# Modules not configured
1764# ---------------------------------------------------------------------------
1765
1766modules modules_install:
1767	@echo >&2 '***'
1768	@echo >&2 '*** The present kernel configuration has modules disabled.'
1769	@echo >&2 '*** To use the module feature, please run "make menuconfig" etc.'
1770	@echo >&2 '*** to enable CONFIG_MODULES.'
1771	@echo >&2 '***'
1772	@exit 1
1773
1774endif # CONFIG_MODULES
1775
1776# Single targets
1777# ---------------------------------------------------------------------------
1778# To build individual files in subdirectories, you can do like this:
1779#
1780#   make foo/bar/baz.s
1781#
1782# The supported suffixes for single-target are listed in 'single-targets'
1783#
1784# To build only under specific subdirectories, you can do like this:
1785#
1786#   make foo/bar/baz/
1787
1788ifdef single-build
1789
1790# .ko is special because modpost is needed
1791single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1792single-no-ko := $(sort $(patsubst %.ko,%.mod, $(MAKECMDGOALS)))
1793
1794$(single-ko): single_modpost
1795	@:
1796$(single-no-ko): descend
1797	@:
1798
1799ifeq ($(KBUILD_EXTMOD),)
1800# For the single build of in-tree modules, use a temporary file to avoid
1801# the situation of modules_install installing an invalid modules.order.
1802MODORDER := .modules.tmp
1803endif
1804
1805PHONY += single_modpost
1806single_modpost: $(single-no-ko) modules_prepare
1807	$(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$m;) } > $(MODORDER)
1808	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1809
1810KBUILD_MODULES := 1
1811
1812export KBUILD_SINGLE_TARGETS := $(addprefix $(extmod_prefix), $(single-no-ko))
1813
1814# trim unrelated directories
1815build-dirs := $(foreach d, $(build-dirs), \
1816			$(if $(filter $(d)/%, $(KBUILD_SINGLE_TARGETS)), $(d)))
1817
1818endif
1819
1820ifndef CONFIG_MODULES
1821KBUILD_MODULES :=
1822endif
1823
1824# Handle descending into subdirectories listed in $(build-dirs)
1825# Preset locale variables to speed up the build process. Limit locale
1826# tweaks to this spot to avoid wrong language settings when running
1827# make menuconfig etc.
1828# Error messages still appears in the original language
1829PHONY += descend $(build-dirs)
1830descend: $(build-dirs)
1831$(build-dirs): prepare
1832	$(Q)$(MAKE) $(build)=$@ \
1833	single-build=$(if $(filter-out $@/, $(filter $@/%, $(KBUILD_SINGLE_TARGETS))),1) \
1834	need-builtin=1 need-modorder=1
1835
1836clean-dirs := $(addprefix _clean_, $(clean-dirs))
1837PHONY += $(clean-dirs) clean
1838$(clean-dirs):
1839	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1840
1841clean: $(clean-dirs)
1842	$(call cmd,rmfiles)
1843	@find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1844		\( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1845		-o -name '*.ko.*' \
1846		-o -name '*.dtb' -o -name '*.dtbo' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1847		-o -name '*.dwo' -o -name '*.lst' \
1848		-o -name '*.su' -o -name '*.mod' \
1849		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1850		-o -name '*.lex.c' -o -name '*.tab.[ch]' \
1851		-o -name '*.asn1.[ch]' \
1852		-o -name '*.symtypes' -o -name 'modules.order' \
1853		-o -name '.tmp_*.o.*' \
1854		-o -name '*.c.[012]*.*' \
1855		-o -name '*.ll' \
1856		-o -name '*.gcno' \
1857		-o -name '*.*.symversions' \) -type f -print | xargs rm -f
1858
1859# Generate tags for editors
1860# ---------------------------------------------------------------------------
1861quiet_cmd_tags = GEN     $@
1862      cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1863
1864tags TAGS cscope gtags: FORCE
1865	$(call cmd,tags)
1866
1867# Script to generate missing namespace dependencies
1868# ---------------------------------------------------------------------------
1869
1870PHONY += nsdeps
1871nsdeps: export KBUILD_NSDEPS=1
1872nsdeps: modules
1873	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1874
1875# Clang Tooling
1876# ---------------------------------------------------------------------------
1877
1878quiet_cmd_gen_compile_commands = GEN     $@
1879      cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
1880
1881$(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
1882	$(if $(KBUILD_EXTMOD),,$(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)) \
1883	$(if $(CONFIG_MODULES), $(MODORDER)) FORCE
1884	$(call if_changed,gen_compile_commands)
1885
1886targets += $(extmod_prefix)compile_commands.json
1887
1888PHONY += clang-tidy clang-analyzer
1889
1890ifdef CONFIG_CC_IS_CLANG
1891quiet_cmd_clang_tools = CHECK   $<
1892      cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
1893
1894clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
1895	$(call cmd,clang_tools)
1896else
1897clang-tidy clang-analyzer:
1898	@echo "$@ requires CC=clang" >&2
1899	@false
1900endif
1901
1902# Scripts to check various things for consistency
1903# ---------------------------------------------------------------------------
1904
1905PHONY += includecheck versioncheck coccicheck export_report
1906
1907includecheck:
1908	find $(srctree)/* $(RCS_FIND_IGNORE) \
1909		-name '*.[hcS]' -type f -print | sort \
1910		| xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1911
1912versioncheck:
1913	find $(srctree)/* $(RCS_FIND_IGNORE) \
1914		-name '*.[hcS]' -type f -print | sort \
1915		| xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1916
1917coccicheck:
1918	$(Q)$(BASH) $(srctree)/scripts/$@
1919
1920export_report:
1921	$(PERL) $(srctree)/scripts/export_report.pl
1922
1923PHONY += checkstack kernelrelease kernelversion image_name
1924
1925# UML needs a little special treatment here.  It wants to use the host
1926# toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
1927# else wants $(ARCH), including people doing cross-builds, which means
1928# that $(SUBARCH) doesn't work here.
1929ifeq ($(ARCH), um)
1930CHECKSTACK_ARCH := $(SUBARCH)
1931else
1932CHECKSTACK_ARCH := $(ARCH)
1933endif
1934checkstack:
1935	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1936	$(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1937
1938kernelrelease:
1939	@echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1940
1941kernelversion:
1942	@echo $(KERNELVERSION)
1943
1944image_name:
1945	@echo $(KBUILD_IMAGE)
1946
1947# Clear a bunch of variables before executing the submake
1948
1949ifeq ($(quiet),silent_)
1950tools_silent=s
1951endif
1952
1953tools/: FORCE
1954	$(Q)mkdir -p $(objtree)/tools
1955	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1956
1957tools/%: FORCE
1958	$(Q)mkdir -p $(objtree)/tools
1959	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1960
1961quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
1962      cmd_rmfiles = rm -rf $(rm-files)
1963
1964# read saved command lines for existing targets
1965existing-targets := $(wildcard $(sort $(targets)))
1966
1967-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
1968
1969endif # config-build
1970endif # mixed-build
1971endif # need-sub-make
1972
1973PHONY += FORCE
1974FORCE:
1975
1976# Declare the contents of the PHONY variable as phony.  We keep that
1977# information in a variable so we can use it in if_changed and friends.
1978.PHONY: $(PHONY)
1979