xref: /linux/Makefile (revision 94e48d6aafef23143f92eadd010c505c49487576)
1# SPDX-License-Identifier: GPL-2.0
2VERSION = 5
3PATCHLEVEL = 13
4SUBLEVEL = 0
5EXTRAVERSION =
6NAME = Opossums on Parade
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 ($(ARCH),sparc64)
399       SRCARCH := sparc
400endif
401
402export cross_compiling :=
403ifneq ($(SRCARCH),$(SUBARCH))
404cross_compiling := 1
405endif
406
407KCONFIG_CONFIG	?= .config
408export KCONFIG_CONFIG
409
410# SHELL used by kbuild
411CONFIG_SHELL := sh
412
413HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
414HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
415HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
416
417ifneq ($(LLVM),)
418HOSTCC	= clang
419HOSTCXX	= clang++
420else
421HOSTCC	= gcc
422HOSTCXX	= g++
423endif
424
425export KBUILD_USERCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
426			      -O2 -fomit-frame-pointer -std=gnu89
427export KBUILD_USERLDFLAGS :=
428
429KBUILD_HOSTCFLAGS   := $(KBUILD_USERCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
430KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
431KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
432KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
433
434# Make variables (CC, etc...)
435CPP		= $(CC) -E
436ifneq ($(LLVM),)
437CC		= clang
438LD		= ld.lld
439AR		= llvm-ar
440NM		= llvm-nm
441OBJCOPY		= llvm-objcopy
442OBJDUMP		= llvm-objdump
443READELF		= llvm-readelf
444STRIP		= llvm-strip
445else
446CC		= $(CROSS_COMPILE)gcc
447LD		= $(CROSS_COMPILE)ld
448AR		= $(CROSS_COMPILE)ar
449NM		= $(CROSS_COMPILE)nm
450OBJCOPY		= $(CROSS_COMPILE)objcopy
451OBJDUMP		= $(CROSS_COMPILE)objdump
452READELF		= $(CROSS_COMPILE)readelf
453STRIP		= $(CROSS_COMPILE)strip
454endif
455PAHOLE		= pahole
456RESOLVE_BTFIDS	= $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
457LEX		= flex
458YACC		= bison
459AWK		= awk
460INSTALLKERNEL  := installkernel
461DEPMOD		= depmod
462PERL		= perl
463PYTHON3		= python3
464CHECK		= sparse
465BASH		= bash
466KGZIP		= gzip
467KBZIP2		= bzip2
468KLZOP		= lzop
469LZMA		= lzma
470LZ4		= lz4c
471XZ		= xz
472ZSTD		= zstd
473
474CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
475		  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
476NOSTDINC_FLAGS :=
477CFLAGS_MODULE   =
478AFLAGS_MODULE   =
479LDFLAGS_MODULE  =
480CFLAGS_KERNEL	=
481AFLAGS_KERNEL	=
482LDFLAGS_vmlinux =
483
484# Use USERINCLUDE when you must reference the UAPI directories only.
485USERINCLUDE    := \
486		-I$(srctree)/arch/$(SRCARCH)/include/uapi \
487		-I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
488		-I$(srctree)/include/uapi \
489		-I$(objtree)/include/generated/uapi \
490                -include $(srctree)/include/linux/compiler-version.h \
491                -include $(srctree)/include/linux/kconfig.h
492
493# Use LINUXINCLUDE when you must reference the include/ directory.
494# Needed to be compatible with the O= option
495LINUXINCLUDE    := \
496		-I$(srctree)/arch/$(SRCARCH)/include \
497		-I$(objtree)/arch/$(SRCARCH)/include/generated \
498		$(if $(building_out_of_srctree),-I$(srctree)/include) \
499		-I$(objtree)/include \
500		$(USERINCLUDE)
501
502KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
503KBUILD_CFLAGS   := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
504		   -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
505		   -Werror=implicit-function-declaration -Werror=implicit-int \
506		   -Werror=return-type -Wno-format-security \
507		   -std=gnu89
508KBUILD_CPPFLAGS := -D__KERNEL__
509KBUILD_AFLAGS_KERNEL :=
510KBUILD_CFLAGS_KERNEL :=
511KBUILD_AFLAGS_MODULE  := -DMODULE
512KBUILD_CFLAGS_MODULE  := -DMODULE
513KBUILD_LDFLAGS_MODULE :=
514KBUILD_LDFLAGS :=
515CLANG_FLAGS :=
516
517export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC
518export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
519export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
520export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
521export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
522
523export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
524export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
525export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
526export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
527export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
528
529# Files to ignore in find ... statements
530
531export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
532			  -name CVS -o -name .pc -o -name .hg -o -name .git \) \
533			  -prune -o
534export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
535			 --exclude CVS --exclude .pc --exclude .hg --exclude .git
536
537# ===========================================================================
538# Rules shared between *config targets and build targets
539
540# Basic helpers built in scripts/basic/
541PHONY += scripts_basic
542scripts_basic:
543	$(Q)$(MAKE) $(build)=scripts/basic
544	$(Q)rm -f .tmp_quiet_recordmcount
545
546PHONY += outputmakefile
547# Before starting out-of-tree build, make sure the source tree is clean.
548# outputmakefile generates a Makefile in the output directory, if using a
549# separate output directory. This allows convenient use of make in the
550# output directory.
551# At the same time when output Makefile generated, generate .gitignore to
552# ignore whole output directory
553outputmakefile:
554ifdef building_out_of_srctree
555	$(Q)if [ -f $(srctree)/.config -o \
556		 -d $(srctree)/include/config -o \
557		 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
558		echo >&2 "***"; \
559		echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
560		echo >&2 "*** in $(abs_srctree)";\
561		echo >&2 "***"; \
562		false; \
563	fi
564	$(Q)ln -fsn $(srctree) source
565	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile $(srctree)
566	$(Q)test -e .gitignore || \
567	{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
568endif
569
570# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
571# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
572# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
573# and from include/config/auto.conf.cmd to detect the compiler upgrade.
574CC_VERSION_TEXT = $(subst $(pound),,$(shell $(CC) --version 2>/dev/null | head -n 1))
575
576ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
577ifneq ($(CROSS_COMPILE),)
578CLANG_FLAGS	+= --target=$(notdir $(CROSS_COMPILE:%-=%))
579endif
580ifeq ($(LLVM_IAS),1)
581CLANG_FLAGS	+= -integrated-as
582else
583CLANG_FLAGS	+= -no-integrated-as
584GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
585CLANG_FLAGS	+= --prefix=$(GCC_TOOLCHAIN_DIR)$(notdir $(CROSS_COMPILE))
586endif
587CLANG_FLAGS	+= -Werror=unknown-warning-option
588KBUILD_CFLAGS	+= $(CLANG_FLAGS)
589KBUILD_AFLAGS	+= $(CLANG_FLAGS)
590export CLANG_FLAGS
591endif
592
593# Include this also for config targets because some architectures need
594# cc-cross-prefix to determine CROSS_COMPILE.
595ifdef need-compiler
596include $(srctree)/scripts/Makefile.compiler
597endif
598
599ifdef config-build
600# ===========================================================================
601# *config targets only - make sure prerequisites are updated, and descend
602# in scripts/kconfig to make the *config target
603
604# Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
605# KBUILD_DEFCONFIG may point out an alternative default configuration
606# used for 'make defconfig'
607include $(srctree)/arch/$(SRCARCH)/Makefile
608export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
609
610config: outputmakefile scripts_basic FORCE
611	$(Q)$(MAKE) $(build)=scripts/kconfig $@
612
613%config: outputmakefile scripts_basic FORCE
614	$(Q)$(MAKE) $(build)=scripts/kconfig $@
615
616else #!config-build
617# ===========================================================================
618# Build targets only - this includes vmlinux, arch specific targets, clean
619# targets and others. In general all targets except *config targets.
620
621# If building an external module we do not care about the all: rule
622# but instead __all depend on modules
623PHONY += all
624ifeq ($(KBUILD_EXTMOD),)
625__all: all
626else
627__all: modules
628endif
629
630# Decide whether to build built-in, modular, or both.
631# Normally, just do built-in.
632
633KBUILD_MODULES :=
634KBUILD_BUILTIN := 1
635
636# If we have only "make modules", don't compile built-in objects.
637ifeq ($(MAKECMDGOALS),modules)
638  KBUILD_BUILTIN :=
639endif
640
641# If we have "make <whatever> modules", compile modules
642# in addition to whatever we do anyway.
643# Just "make" or "make all" shall build modules as well
644
645ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
646  KBUILD_MODULES := 1
647endif
648
649ifeq ($(MAKECMDGOALS),)
650  KBUILD_MODULES := 1
651endif
652
653export KBUILD_MODULES KBUILD_BUILTIN
654
655ifdef need-config
656include include/config/auto.conf
657endif
658
659ifeq ($(KBUILD_EXTMOD),)
660# Objects we will link into vmlinux / subdirs we need to visit
661core-y		:= init/ usr/
662drivers-y	:= drivers/ sound/
663drivers-$(CONFIG_SAMPLES) += samples/
664drivers-$(CONFIG_NET) += net/
665drivers-y	+= virt/
666libs-y		:= lib/
667endif # KBUILD_EXTMOD
668
669# The all: target is the default when no target is given on the
670# command line.
671# This allow a user to issue only 'make' to build a kernel including modules
672# Defaults to vmlinux, but the arch makefile usually adds further targets
673all: vmlinux
674
675CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage \
676	$(call cc-option,-fno-tree-loop-im) \
677	$(call cc-disable-warning,maybe-uninitialized,)
678export CFLAGS_GCOV
679
680# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
681ifdef CONFIG_FUNCTION_TRACER
682  CC_FLAGS_FTRACE := -pg
683endif
684
685RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
686RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
687RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
688RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
689RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
690RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
691export RETPOLINE_CFLAGS
692export RETPOLINE_VDSO_CFLAGS
693
694include $(srctree)/arch/$(SRCARCH)/Makefile
695
696ifdef need-config
697ifdef may-sync-config
698# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
699# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
700# because some architectures define CROSS_COMPILE there.
701include include/config/auto.conf.cmd
702
703$(KCONFIG_CONFIG):
704	@echo >&2 '***'
705	@echo >&2 '*** Configuration file "$@" not found!'
706	@echo >&2 '***'
707	@echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
708	@echo >&2 '*** "make menuconfig" or "make xconfig").'
709	@echo >&2 '***'
710	@/bin/false
711
712# The actual configuration files used during the build are stored in
713# include/generated/ and include/config/. Update them if .config is newer than
714# include/config/auto.conf (which mirrors .config).
715#
716# This exploits the 'multi-target pattern rule' trick.
717# The syncconfig should be executed only once to make all the targets.
718# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
719quiet_cmd_syncconfig = SYNC    $@
720      cmd_syncconfig = $(MAKE) -f $(srctree)/Makefile syncconfig
721
722%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h: $(KCONFIG_CONFIG)
723	+$(call cmd,syncconfig)
724else # !may-sync-config
725# External modules and some install targets need include/generated/autoconf.h
726# and include/config/auto.conf but do not care if they are up-to-date.
727# Use auto.conf to trigger the test
728PHONY += include/config/auto.conf
729
730include/config/auto.conf:
731	$(Q)test -e include/generated/autoconf.h -a -e $@ || (		\
732	echo >&2;							\
733	echo >&2 "  ERROR: Kernel configuration is invalid.";		\
734	echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
735	echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";	\
736	echo >&2 ;							\
737	/bin/false)
738
739endif # may-sync-config
740endif # need-config
741
742KBUILD_CFLAGS	+= $(call cc-option,-fno-delete-null-pointer-checks,)
743KBUILD_CFLAGS	+= $(call cc-disable-warning,frame-address,)
744KBUILD_CFLAGS	+= $(call cc-disable-warning, format-truncation)
745KBUILD_CFLAGS	+= $(call cc-disable-warning, format-overflow)
746KBUILD_CFLAGS	+= $(call cc-disable-warning, address-of-packed-member)
747
748ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
749KBUILD_CFLAGS += -O2
750else ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3
751KBUILD_CFLAGS += -O3
752else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
753KBUILD_CFLAGS += -Os
754endif
755
756# Tell gcc to never replace conditional load with a non-conditional one
757KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
758KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
759
760ifdef CONFIG_READABLE_ASM
761# Disable optimizations that make assembler listings hard to read.
762# reorder blocks reorders the control in the function
763# ipa clone creates specialized cloned functions
764# partial inlining inlines only parts of functions
765KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
766                 $(call cc-option,-fno-ipa-cp-clone,) \
767                 $(call cc-option,-fno-partial-inlining)
768endif
769
770ifneq ($(CONFIG_FRAME_WARN),0)
771KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
772endif
773
774stackp-flags-y                                    := -fno-stack-protector
775stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
776stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
777
778KBUILD_CFLAGS += $(stackp-flags-y)
779
780ifdef CONFIG_CC_IS_CLANG
781KBUILD_CPPFLAGS += -Qunused-arguments
782KBUILD_CFLAGS += -Wno-format-invalid-specifier
783KBUILD_CFLAGS += -Wno-gnu
784# CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
785# source of a reference will be _MergedGlobals and not on of the whitelisted names.
786# See modpost pattern 2
787KBUILD_CFLAGS += -mno-global-merge
788else
789
790# Warn about unmarked fall-throughs in switch statement.
791# Disabled for clang while comment to attribute conversion happens and
792# https://github.com/ClangBuiltLinux/linux/issues/636 is discussed.
793KBUILD_CFLAGS += $(call cc-option,-Wimplicit-fallthrough,)
794endif
795
796# These warnings generated too much noise in a regular build.
797# Use make W=1 to enable them (see scripts/Makefile.extrawarn)
798KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
799
800KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
801ifdef CONFIG_FRAME_POINTER
802KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
803else
804# Some targets (ARM with Thumb2, for example), can't be built with frame
805# pointers.  For those, we don't have FUNCTION_TRACER automatically
806# select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
807# incompatible with -fomit-frame-pointer with current GCC, so we don't use
808# -fomit-frame-pointer with FUNCTION_TRACER.
809ifndef CONFIG_FUNCTION_TRACER
810KBUILD_CFLAGS	+= -fomit-frame-pointer
811endif
812endif
813
814# Initialize all stack variables with a 0xAA pattern.
815ifdef CONFIG_INIT_STACK_ALL_PATTERN
816KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
817endif
818
819# Initialize all stack variables with a zero value.
820ifdef CONFIG_INIT_STACK_ALL_ZERO
821# Future support for zero initialization is still being debated, see
822# https://bugs.llvm.org/show_bug.cgi?id=45497. These flags are subject to being
823# renamed or dropped.
824KBUILD_CFLAGS	+= -ftrivial-auto-var-init=zero
825KBUILD_CFLAGS	+= -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
826endif
827
828# While VLAs have been removed, GCC produces unreachable stack probes
829# for the randomize_kstack_offset feature. Disable it for all compilers.
830KBUILD_CFLAGS	+= $(call cc-option, -fno-stack-clash-protection)
831
832DEBUG_CFLAGS	:=
833
834# Workaround for GCC versions < 5.0
835# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61801
836ifdef CONFIG_CC_IS_GCC
837DEBUG_CFLAGS	+= $(call cc-ifversion, -lt, 0500, $(call cc-option, -fno-var-tracking-assignments))
838endif
839
840ifdef CONFIG_DEBUG_INFO
841
842ifdef CONFIG_DEBUG_INFO_SPLIT
843DEBUG_CFLAGS	+= -gsplit-dwarf
844else
845DEBUG_CFLAGS	+= -g
846endif
847
848ifneq ($(LLVM_IAS),1)
849KBUILD_AFLAGS	+= -Wa,-gdwarf-2
850endif
851
852ifndef CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT
853dwarf-version-$(CONFIG_DEBUG_INFO_DWARF4) := 4
854dwarf-version-$(CONFIG_DEBUG_INFO_DWARF5) := 5
855DEBUG_CFLAGS	+= -gdwarf-$(dwarf-version-y)
856endif
857
858ifdef CONFIG_DEBUG_INFO_REDUCED
859DEBUG_CFLAGS	+= $(call cc-option, -femit-struct-debug-baseonly) \
860		   $(call cc-option,-fno-var-tracking)
861endif
862
863ifdef CONFIG_DEBUG_INFO_COMPRESSED
864DEBUG_CFLAGS	+= -gz=zlib
865KBUILD_AFLAGS	+= -gz=zlib
866KBUILD_LDFLAGS	+= --compress-debug-sections=zlib
867endif
868
869endif # CONFIG_DEBUG_INFO
870
871KBUILD_CFLAGS += $(DEBUG_CFLAGS)
872export DEBUG_CFLAGS
873
874ifdef CONFIG_FUNCTION_TRACER
875ifdef CONFIG_FTRACE_MCOUNT_USE_CC
876  CC_FLAGS_FTRACE	+= -mrecord-mcount
877  ifdef CONFIG_HAVE_NOP_MCOUNT
878    ifeq ($(call cc-option-yn, -mnop-mcount),y)
879      CC_FLAGS_FTRACE	+= -mnop-mcount
880      CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
881    endif
882  endif
883endif
884ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
885  CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
886endif
887ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
888  ifdef CONFIG_HAVE_C_RECORDMCOUNT
889    BUILD_C_RECORDMCOUNT := y
890    export BUILD_C_RECORDMCOUNT
891  endif
892endif
893ifdef CONFIG_HAVE_FENTRY
894  ifeq ($(call cc-option-yn, -mfentry),y)
895    CC_FLAGS_FTRACE	+= -mfentry
896    CC_FLAGS_USING	+= -DCC_USING_FENTRY
897  endif
898endif
899export CC_FLAGS_FTRACE
900KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
901KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
902endif
903
904# We trigger additional mismatches with less inlining
905ifdef CONFIG_DEBUG_SECTION_MISMATCH
906KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
907endif
908
909ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
910KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
911LDFLAGS_vmlinux += --gc-sections
912endif
913
914ifdef CONFIG_SHADOW_CALL_STACK
915CC_FLAGS_SCS	:= -fsanitize=shadow-call-stack
916KBUILD_CFLAGS	+= $(CC_FLAGS_SCS)
917export CC_FLAGS_SCS
918endif
919
920ifdef CONFIG_LTO_CLANG
921ifdef CONFIG_LTO_CLANG_THIN
922CC_FLAGS_LTO	:= -flto=thin -fsplit-lto-unit
923KBUILD_LDFLAGS	+= --thinlto-cache-dir=$(extmod_prefix).thinlto-cache
924else
925CC_FLAGS_LTO	:= -flto
926endif
927CC_FLAGS_LTO	+= -fvisibility=hidden
928
929# Limit inlining across translation units to reduce binary size
930KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
931
932# Check for frame size exceeding threshold during prolog/epilog insertion
933# when using lld < 13.0.0.
934ifneq ($(CONFIG_FRAME_WARN),0)
935ifeq ($(shell test $(CONFIG_LLD_VERSION) -lt 130000; echo $$?),0)
936KBUILD_LDFLAGS	+= -plugin-opt=-warn-stack-size=$(CONFIG_FRAME_WARN)
937endif
938endif
939endif
940
941ifdef CONFIG_LTO
942KBUILD_CFLAGS	+= -fno-lto $(CC_FLAGS_LTO)
943KBUILD_AFLAGS	+= -fno-lto
944export CC_FLAGS_LTO
945endif
946
947ifdef CONFIG_CFI_CLANG
948CC_FLAGS_CFI	:= -fsanitize=cfi \
949		   -fsanitize-cfi-cross-dso \
950		   -fno-sanitize-cfi-canonical-jump-tables \
951		   -fno-sanitize-trap=cfi \
952		   -fno-sanitize-blacklist
953
954ifdef CONFIG_CFI_PERMISSIVE
955CC_FLAGS_CFI	+= -fsanitize-recover=cfi
956endif
957
958# If LTO flags are filtered out, we must also filter out CFI.
959CC_FLAGS_LTO	+= $(CC_FLAGS_CFI)
960KBUILD_CFLAGS	+= $(CC_FLAGS_CFI)
961export CC_FLAGS_CFI
962endif
963
964ifdef CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_32B
965KBUILD_CFLAGS += -falign-functions=32
966endif
967
968# arch Makefile may override CC so keep this after arch Makefile is included
969NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
970
971# warn about C99 declaration after statement
972KBUILD_CFLAGS += -Wdeclaration-after-statement
973
974# Variable Length Arrays (VLAs) should not be used anywhere in the kernel
975KBUILD_CFLAGS += -Wvla
976
977# disable pointer signed / unsigned warnings in gcc 4.0
978KBUILD_CFLAGS += -Wno-pointer-sign
979
980# disable stringop warnings in gcc 8+
981KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
982
983# We'll want to enable this eventually, but it's not going away for 5.7 at least
984KBUILD_CFLAGS += $(call cc-disable-warning, zero-length-bounds)
985KBUILD_CFLAGS += $(call cc-disable-warning, array-bounds)
986KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
987
988# Another good warning that we'll want to enable eventually
989KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
990
991# Enabled with W=2, disabled by default as noisy
992KBUILD_CFLAGS += $(call cc-disable-warning, maybe-uninitialized)
993
994# disable invalid "can't wrap" optimizations for signed / pointers
995KBUILD_CFLAGS	+= -fno-strict-overflow
996
997# Make sure -fstack-check isn't enabled (like gentoo apparently did)
998KBUILD_CFLAGS  += -fno-stack-check
999
1000# conserve stack if available
1001KBUILD_CFLAGS   += $(call cc-option,-fconserve-stack)
1002
1003# Prohibit date/time macros, which would make the build non-deterministic
1004KBUILD_CFLAGS   += -Werror=date-time
1005
1006# enforce correct pointer usage
1007KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)
1008
1009# Require designated initializers for all marked structures
1010KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)
1011
1012# change __FILE__ to the relative path from the srctree
1013KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
1014
1015# include additional Makefiles when needed
1016include-y			:= scripts/Makefile.extrawarn
1017include-$(CONFIG_KASAN)		+= scripts/Makefile.kasan
1018include-$(CONFIG_KCSAN)		+= scripts/Makefile.kcsan
1019include-$(CONFIG_UBSAN)		+= scripts/Makefile.ubsan
1020include-$(CONFIG_KCOV)		+= scripts/Makefile.kcov
1021include-$(CONFIG_GCC_PLUGINS)	+= scripts/Makefile.gcc-plugins
1022
1023include $(addprefix $(srctree)/, $(include-y))
1024
1025# scripts/Makefile.gcc-plugins is intentionally included last.
1026# Do not add $(call cc-option,...) below this line. When you build the kernel
1027# from the clean source tree, the GCC plugins do not exist at this point.
1028
1029# Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
1030KBUILD_CPPFLAGS += $(KCPPFLAGS)
1031KBUILD_AFLAGS   += $(KAFLAGS)
1032KBUILD_CFLAGS   += $(KCFLAGS)
1033
1034KBUILD_LDFLAGS_MODULE += --build-id=sha1
1035LDFLAGS_vmlinux += --build-id=sha1
1036
1037ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1038LDFLAGS_vmlinux	+= $(call ld-option, -X,)
1039endif
1040
1041ifeq ($(CONFIG_RELR),y)
1042LDFLAGS_vmlinux	+= --pack-dyn-relocs=relr --use-android-relr-tags
1043endif
1044
1045# We never want expected sections to be placed heuristically by the
1046# linker. All sections should be explicitly named in the linker script.
1047ifdef CONFIG_LD_ORPHAN_WARN
1048LDFLAGS_vmlinux += --orphan-handling=warn
1049endif
1050
1051# Align the bit size of userspace programs with the kernel
1052KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1053KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1054
1055# make the checker run with the right architecture
1056CHECKFLAGS += --arch=$(ARCH)
1057
1058# insure the checker run with the right endianness
1059CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1060
1061# the checker needs the correct machine size
1062CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1063
1064# Default kernel image to build when no specific target is given.
1065# KBUILD_IMAGE may be overruled on the command line or
1066# set in the environment
1067# Also any assignments in arch/$(ARCH)/Makefile take precedence over
1068# this default value
1069export KBUILD_IMAGE ?= vmlinux
1070
1071#
1072# INSTALL_PATH specifies where to place the updated kernel and system map
1073# images. Default is /boot, but you can set it to other values
1074export	INSTALL_PATH ?= /boot
1075
1076#
1077# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1078# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1079# an argument if needed. Otherwise it defaults to the kernel install path
1080#
1081export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1082
1083#
1084# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1085# relocations required by build roots.  This is not defined in the
1086# makefile but the argument can be passed to make if needed.
1087#
1088
1089MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1090export MODLIB
1091
1092HOST_LIBELF_LIBS = $(shell pkg-config libelf --libs 2>/dev/null || echo -lelf)
1093
1094has_libelf = $(call try-run,\
1095               echo "int main() {}" | $(HOSTCC) $(KBUILD_HOSTLDFLAGS) -xc -o /dev/null $(HOST_LIBELF_LIBS) -,1,0)
1096
1097ifdef CONFIG_STACK_VALIDATION
1098  ifeq ($(has_libelf),1)
1099    objtool_target := tools/objtool FORCE
1100  else
1101    SKIP_STACK_VALIDATION := 1
1102    export SKIP_STACK_VALIDATION
1103  endif
1104endif
1105
1106PHONY += resolve_btfids_clean
1107
1108resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1109
1110# tools/bpf/resolve_btfids directory might not exist
1111# in output directory, skip its clean in that case
1112resolve_btfids_clean:
1113ifneq ($(wildcard $(resolve_btfids_O)),)
1114	$(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1115endif
1116
1117ifdef CONFIG_BPF
1118ifdef CONFIG_DEBUG_INFO_BTF
1119  ifeq ($(has_libelf),1)
1120    resolve_btfids_target := tools/bpf/resolve_btfids FORCE
1121  else
1122    ERROR_RESOLVE_BTFIDS := 1
1123  endif
1124endif # CONFIG_DEBUG_INFO_BTF
1125endif # CONFIG_BPF
1126
1127PHONY += prepare0
1128
1129export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
1130export MODORDER := $(extmod_prefix)modules.order
1131export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
1132
1133ifeq ($(KBUILD_EXTMOD),)
1134core-y		+= kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
1135
1136vmlinux-dirs	:= $(patsubst %/,%,$(filter %/, \
1137		     $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
1138		     $(libs-y) $(libs-m)))
1139
1140vmlinux-alldirs	:= $(sort $(vmlinux-dirs) Documentation \
1141		     $(patsubst %/,%,$(filter %/, $(core-) \
1142			$(drivers-) $(libs-))))
1143
1144subdir-modorder := $(addsuffix modules.order,$(filter %/, \
1145			$(core-y) $(core-m) $(libs-y) $(libs-m) \
1146			$(drivers-y) $(drivers-m)))
1147
1148build-dirs	:= $(vmlinux-dirs)
1149clean-dirs	:= $(vmlinux-alldirs)
1150
1151# Externally visible symbols (used by link-vmlinux.sh)
1152KBUILD_VMLINUX_OBJS := $(head-y) $(patsubst %/,%/built-in.a, $(core-y))
1153KBUILD_VMLINUX_OBJS += $(addsuffix built-in.a, $(filter %/, $(libs-y)))
1154ifdef CONFIG_MODULES
1155KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1156KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1157else
1158KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1159endif
1160KBUILD_VMLINUX_OBJS += $(patsubst %/,%/built-in.a, $(drivers-y))
1161
1162export KBUILD_VMLINUX_OBJS KBUILD_VMLINUX_LIBS
1163export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1164# used by scripts/Makefile.package
1165export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) LICENSES arch include scripts tools)
1166
1167vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
1168
1169# Recurse until adjust_autoksyms.sh is satisfied
1170PHONY += autoksyms_recursive
1171ifdef CONFIG_TRIM_UNUSED_KSYMS
1172# For the kernel to actually contain only the needed exported symbols,
1173# we have to build modules as well to determine what those symbols are.
1174# (this can be evaluated only once include/config/auto.conf has been included)
1175KBUILD_MODULES := 1
1176
1177autoksyms_recursive: descend modules.order
1178	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1179	  "$(MAKE) -f $(srctree)/Makefile vmlinux"
1180endif
1181
1182autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1183
1184quiet_cmd_autoksyms_h = GEN     $@
1185      cmd_autoksyms_h = mkdir -p $(dir $@); \
1186			$(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@
1187
1188$(autoksyms_h):
1189	$(call cmd,autoksyms_h)
1190
1191ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1192
1193# Final link of vmlinux with optional arch pass after final link
1194cmd_link-vmlinux =                                                 \
1195	$(CONFIG_SHELL) $< "$(LD)" "$(KBUILD_LDFLAGS)" "$(LDFLAGS_vmlinux)";    \
1196	$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1197
1198vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1199	+$(call if_changed_dep,link-vmlinux)
1200
1201targets := vmlinux
1202
1203# The actual objects are generated when descending,
1204# make sure no implicit rule kicks in
1205$(sort $(vmlinux-deps) $(subdir-modorder)): descend ;
1206
1207filechk_kernel.release = \
1208	echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1209
1210# Store (new) KERNELRELEASE string in include/config/kernel.release
1211include/config/kernel.release: FORCE
1212	$(call filechk,kernel.release)
1213
1214# Additional helpers built in scripts/
1215# Carefully list dependencies so we do not try to build scripts twice
1216# in parallel
1217PHONY += scripts
1218scripts: scripts_basic scripts_dtc
1219	$(Q)$(MAKE) $(build)=$(@)
1220
1221# Things we need to do before we recursively start building the kernel
1222# or the modules are listed in "prepare".
1223# A multi level approach is used. prepareN is processed before prepareN-1.
1224# archprepare is used in arch Makefiles and when processed asm symlink,
1225# version.h and scripts_basic is processed / created.
1226
1227PHONY += prepare archprepare
1228
1229archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1230	asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h \
1231	include/generated/autoconf.h remove-stale-files
1232
1233prepare0: archprepare
1234	$(Q)$(MAKE) $(build)=scripts/mod
1235	$(Q)$(MAKE) $(build)=.
1236
1237# All the preparing..
1238prepare: prepare0 prepare-objtool prepare-resolve_btfids
1239
1240PHONY += remove-stale-files
1241remove-stale-files:
1242	$(Q)$(srctree)/scripts/remove-stale-files
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	@echo >&2 "=================== WARNING ==================="
1349	@echo >&2 "Since Linux 5.5, 'make headers_check' is no-op,"
1350	@echo >&2 "and will be removed after Linux 5.15 release."
1351	@echo >&2 "Please remove headers_check from your scripts."
1352	@echo >&2 "==============================================="
1353
1354ifdef CONFIG_HEADERS_INSTALL
1355prepare: headers
1356endif
1357
1358PHONY += scripts_unifdef
1359scripts_unifdef: scripts_basic
1360	$(Q)$(MAKE) $(build)=scripts scripts/unifdef
1361
1362# ---------------------------------------------------------------------------
1363# Kernel selftest
1364
1365PHONY += kselftest
1366kselftest:
1367	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1368
1369kselftest-%: FORCE
1370	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1371
1372PHONY += kselftest-merge
1373kselftest-merge:
1374	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1375	$(Q)find $(srctree)/tools/testing/selftests -name config | \
1376		xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1377	$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1378
1379# ---------------------------------------------------------------------------
1380# Devicetree files
1381
1382ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1383dtstree := arch/$(SRCARCH)/boot/dts
1384endif
1385
1386ifneq ($(dtstree),)
1387
1388%.dtb: include/config/kernel.release scripts_dtc
1389	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1390
1391%.dtbo: include/config/kernel.release scripts_dtc
1392	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1393
1394PHONY += dtbs dtbs_install dtbs_check
1395dtbs: include/config/kernel.release scripts_dtc
1396	$(Q)$(MAKE) $(build)=$(dtstree)
1397
1398ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1399export CHECK_DTBS=y
1400dtbs: dt_binding_check
1401endif
1402
1403dtbs_check: dtbs
1404
1405dtbs_install:
1406	$(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1407
1408ifdef CONFIG_OF_EARLY_FLATTREE
1409all: dtbs
1410endif
1411
1412endif
1413
1414PHONY += scripts_dtc
1415scripts_dtc: scripts_basic
1416	$(Q)$(MAKE) $(build)=scripts/dtc
1417
1418ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1419export CHECK_DT_BINDING=y
1420endif
1421
1422PHONY += dt_binding_check
1423dt_binding_check: scripts_dtc
1424	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1425
1426# ---------------------------------------------------------------------------
1427# Modules
1428
1429ifdef CONFIG_MODULES
1430
1431# By default, build modules as well
1432
1433all: modules
1434
1435# When we're building modules with modversions, we need to consider
1436# the built-in objects during the descend as well, in order to
1437# make sure the checksums are up to date before we record them.
1438ifdef CONFIG_MODVERSIONS
1439  KBUILD_BUILTIN := 1
1440endif
1441
1442# Build modules
1443#
1444# A module can be listed more than once in obj-m resulting in
1445# duplicate lines in modules.order files.  Those are removed
1446# using awk while concatenating to the final file.
1447
1448PHONY += modules
1449modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_check modules_prepare
1450
1451cmd_modules_order = $(AWK) '!x[$$0]++' $(real-prereqs) > $@
1452
1453modules.order: $(subdir-modorder) FORCE
1454	$(call if_changed,modules_order)
1455
1456targets += modules.order
1457
1458# Target to prepare building external modules
1459PHONY += modules_prepare
1460modules_prepare: prepare
1461	$(Q)$(MAKE) $(build)=scripts scripts/module.lds
1462
1463export modules_sign_only :=
1464
1465ifeq ($(CONFIG_MODULE_SIG),y)
1466PHONY += modules_sign
1467modules_sign: modules_install
1468	@:
1469
1470# modules_sign is a subset of modules_install.
1471# 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1472ifeq ($(filter modules_install,$(MAKECMDGOALS)),)
1473modules_sign_only := y
1474endif
1475endif
1476
1477modinst_pre :=
1478ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
1479modinst_pre := __modinst_pre
1480endif
1481
1482modules_install: $(modinst_pre)
1483PHONY += __modinst_pre
1484__modinst_pre:
1485	@rm -rf $(MODLIB)/kernel
1486	@rm -f $(MODLIB)/source
1487	@mkdir -p $(MODLIB)/kernel
1488	@ln -s $(abspath $(srctree)) $(MODLIB)/source
1489	@if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
1490		rm -f $(MODLIB)/build ; \
1491		ln -s $(CURDIR) $(MODLIB)/build ; \
1492	fi
1493	@sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order
1494	@cp -f modules.builtin $(MODLIB)/
1495	@cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
1496
1497endif # CONFIG_MODULES
1498
1499###
1500# Cleaning is done on three levels.
1501# make clean     Delete most generated files
1502#                Leave enough to build external modules
1503# make mrproper  Delete the current configuration, and all generated files
1504# make distclean Remove editor backup files, patch leftover files and the like
1505
1506# Directories & files removed with 'make clean'
1507CLEAN_FILES += include/ksym vmlinux.symvers modules-only.symvers \
1508	       modules.builtin modules.builtin.modinfo modules.nsdeps \
1509	       compile_commands.json .thinlto-cache
1510
1511# Directories & files removed with 'make mrproper'
1512MRPROPER_FILES += include/config include/generated          \
1513		  arch/$(SRCARCH)/include/generated .tmp_objdiff \
1514		  debian snap tar-install \
1515		  .config .config.old .version \
1516		  Module.symvers \
1517		  certs/signing_key.pem certs/signing_key.x509 \
1518		  certs/x509.genkey \
1519		  vmlinux-gdb.py \
1520		  *.spec
1521
1522# clean - Delete most, but leave enough to build external modules
1523#
1524clean: rm-files := $(CLEAN_FILES)
1525
1526PHONY += archclean vmlinuxclean
1527
1528vmlinuxclean:
1529	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1530	$(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1531
1532clean: archclean vmlinuxclean resolve_btfids_clean
1533
1534# mrproper - Delete all generated files, including .config
1535#
1536mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1537mrproper-dirs      := $(addprefix _mrproper_,scripts)
1538
1539PHONY += $(mrproper-dirs) mrproper
1540$(mrproper-dirs):
1541	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1542
1543mrproper: clean $(mrproper-dirs)
1544	$(call cmd,rmfiles)
1545
1546# distclean
1547#
1548PHONY += distclean
1549
1550distclean: mrproper
1551	@find . $(RCS_FIND_IGNORE) \
1552		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1553		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
1554		-o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1555		-o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1556		-type f -print | xargs rm -f
1557
1558
1559# Packaging of the kernel to various formats
1560# ---------------------------------------------------------------------------
1561
1562%src-pkg: FORCE
1563	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1564%pkg: include/config/kernel.release FORCE
1565	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1566
1567# Brief documentation of the typical targets used
1568# ---------------------------------------------------------------------------
1569
1570boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1571boards := $(sort $(notdir $(boards)))
1572board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1573board-dirs := $(sort $(notdir $(board-dirs:/=)))
1574
1575PHONY += help
1576help:
1577	@echo  'Cleaning targets:'
1578	@echo  '  clean		  - Remove most generated files but keep the config and'
1579	@echo  '                    enough build support to build external modules'
1580	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
1581	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
1582	@echo  ''
1583	@echo  'Configuration targets:'
1584	@$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1585	@echo  ''
1586	@echo  'Other generic targets:'
1587	@echo  '  all		  - Build all targets marked with [*]'
1588	@echo  '* vmlinux	  - Build the bare kernel'
1589	@echo  '* modules	  - Build all modules'
1590	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1591	@echo  '  dir/            - Build all files in dir and below'
1592	@echo  '  dir/file.[ois]  - Build specified target only'
1593	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1594	@echo  '                    (requires compiler support for LLVM assembly generation)'
1595	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1596	@echo  '                    (requires a recent binutils and recent build (System.map))'
1597	@echo  '  dir/file.ko     - Build module including final link'
1598	@echo  '  modules_prepare - Set up for building external modules'
1599	@echo  '  tags/TAGS	  - Generate tags file for editors'
1600	@echo  '  cscope	  - Generate cscope index'
1601	@echo  '  gtags           - Generate GNU GLOBAL index'
1602	@echo  '  kernelrelease	  - Output the release version string (use with make -s)'
1603	@echo  '  kernelversion	  - Output the version stored in Makefile (use with make -s)'
1604	@echo  '  image_name	  - Output the image name (use with make -s)'
1605	@echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1606	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1607	 echo  ''
1608	@echo  'Static analysers:'
1609	@echo  '  checkstack      - Generate a list of stack hogs'
1610	@echo  '  versioncheck    - Sanity check on version.h usage'
1611	@echo  '  includecheck    - Check for duplicate included header files'
1612	@echo  '  export_report   - List the usages of all exported symbols'
1613	@echo  '  headerdep       - Detect inclusion cycles in headers'
1614	@echo  '  coccicheck      - Check with Coccinelle'
1615	@echo  '  clang-analyzer  - Check with clang static analyzer'
1616	@echo  '  clang-tidy      - Check with clang-tidy'
1617	@echo  ''
1618	@echo  'Tools:'
1619	@echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1620	@echo  ''
1621	@echo  'Kernel selftest:'
1622	@echo  '  kselftest         - Build and run kernel selftest'
1623	@echo  '                      Build, install, and boot kernel before'
1624	@echo  '                      running kselftest on it'
1625	@echo  '                      Run as root for full coverage'
1626	@echo  '  kselftest-all     - Build kernel selftest'
1627	@echo  '  kselftest-install - Build and install kernel selftest'
1628	@echo  '  kselftest-clean   - Remove all generated kselftest files'
1629	@echo  '  kselftest-merge   - Merge all the config dependencies of'
1630	@echo  '		      kselftest to existing .config.'
1631	@echo  ''
1632	@$(if $(dtstree), \
1633		echo 'Devicetree:'; \
1634		echo '* dtbs             - Build device tree blobs for enabled boards'; \
1635		echo '  dtbs_install     - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1636		echo '  dt_binding_check - Validate device tree binding documents'; \
1637		echo '  dtbs_check       - Validate device tree source files';\
1638		echo '')
1639
1640	@echo 'Userspace tools targets:'
1641	@echo '  use "make tools/help"'
1642	@echo '  or  "cd tools; make help"'
1643	@echo  ''
1644	@echo  'Kernel packaging:'
1645	@$(MAKE) -f $(srctree)/scripts/Makefile.package help
1646	@echo  ''
1647	@echo  'Documentation targets:'
1648	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1649	@echo  ''
1650	@echo  'Architecture specific targets ($(SRCARCH)):'
1651	@$(if $(archhelp),$(archhelp),\
1652		echo '  No architecture specific help defined for $(SRCARCH)')
1653	@echo  ''
1654	@$(if $(boards), \
1655		$(foreach b, $(boards), \
1656		printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1657		echo '')
1658	@$(if $(board-dirs), \
1659		$(foreach b, $(board-dirs), \
1660		printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1661		printf "  %-16s - Show all of the above\\n" help-boards; \
1662		echo '')
1663
1664	@echo  '  make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1665	@echo  '  make V=2   [targets] 2 => give reason for rebuild of target'
1666	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1667	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1668	@echo  '                       (sparse by default)'
1669	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1670	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1671	@echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
1672	@echo  '		1: warnings which may be relevant and do not occur too often'
1673	@echo  '		2: warnings which occur quite often but may still be relevant'
1674	@echo  '		3: more obscure warnings, can most likely be ignored'
1675	@echo  '		Multiple levels can be combined with W=12 or W=123'
1676	@echo  ''
1677	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
1678	@echo  'For further info see the ./README file'
1679
1680
1681help-board-dirs := $(addprefix help-,$(board-dirs))
1682
1683help-boards: $(help-board-dirs)
1684
1685boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1686
1687$(help-board-dirs): help-%:
1688	@echo  'Architecture specific targets ($(SRCARCH) $*):'
1689	@$(if $(boards-per-dir), \
1690		$(foreach b, $(boards-per-dir), \
1691		printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1692		echo '')
1693
1694
1695# Documentation targets
1696# ---------------------------------------------------------------------------
1697DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1698	       linkcheckdocs dochelp refcheckdocs
1699PHONY += $(DOC_TARGETS)
1700$(DOC_TARGETS):
1701	$(Q)$(MAKE) $(build)=Documentation $@
1702
1703# Misc
1704# ---------------------------------------------------------------------------
1705
1706PHONY += scripts_gdb
1707scripts_gdb: prepare0
1708	$(Q)$(MAKE) $(build)=scripts/gdb
1709	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1710
1711ifdef CONFIG_GDB_SCRIPTS
1712all: scripts_gdb
1713endif
1714
1715else # KBUILD_EXTMOD
1716
1717###
1718# External module support.
1719# When building external modules the kernel used as basis is considered
1720# read-only, and no consistency checks are made and the make
1721# system is not used on the basis kernel. If updates are required
1722# in the basis kernel ordinary make commands (without M=...) must be used.
1723
1724# We are always building only modules.
1725KBUILD_BUILTIN :=
1726KBUILD_MODULES := 1
1727
1728build-dirs := $(KBUILD_EXTMOD)
1729$(MODORDER): descend
1730	@:
1731
1732compile_commands.json: $(extmod_prefix)compile_commands.json
1733PHONY += compile_commands.json
1734
1735clean-dirs := $(KBUILD_EXTMOD)
1736clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1737	$(KBUILD_EXTMOD)/compile_commands.json $(KBUILD_EXTMOD)/.thinlto-cache
1738
1739PHONY += help
1740help:
1741	@echo  '  Building external modules.'
1742	@echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1743	@echo  ''
1744	@echo  '  modules         - default target, build the module(s)'
1745	@echo  '  modules_install - install the module'
1746	@echo  '  clean           - remove generated files in module directory only'
1747	@echo  ''
1748
1749# no-op for external module builds
1750PHONY += prepare modules_prepare
1751
1752endif # KBUILD_EXTMOD
1753
1754# ---------------------------------------------------------------------------
1755# Modules
1756
1757PHONY += modules modules_install
1758
1759ifdef CONFIG_MODULES
1760
1761modules: modules_check
1762	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1763
1764PHONY += modules_check
1765modules_check: $(MODORDER)
1766	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1767
1768quiet_cmd_depmod = DEPMOD  $(MODLIB)
1769      cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1770                   $(KERNELRELEASE)
1771
1772modules_install:
1773	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1774	$(call cmd,depmod)
1775
1776else # CONFIG_MODULES
1777
1778# Modules not configured
1779# ---------------------------------------------------------------------------
1780
1781modules modules_install:
1782	@echo >&2 '***'
1783	@echo >&2 '*** The present kernel configuration has modules disabled.'
1784	@echo >&2 '*** To use the module feature, please run "make menuconfig" etc.'
1785	@echo >&2 '*** to enable CONFIG_MODULES.'
1786	@echo >&2 '***'
1787	@exit 1
1788
1789endif # CONFIG_MODULES
1790
1791# Single targets
1792# ---------------------------------------------------------------------------
1793# To build individual files in subdirectories, you can do like this:
1794#
1795#   make foo/bar/baz.s
1796#
1797# The supported suffixes for single-target are listed in 'single-targets'
1798#
1799# To build only under specific subdirectories, you can do like this:
1800#
1801#   make foo/bar/baz/
1802
1803ifdef single-build
1804
1805# .ko is special because modpost is needed
1806single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1807single-no-ko := $(sort $(patsubst %.ko,%.mod, $(MAKECMDGOALS)))
1808
1809$(single-ko): single_modpost
1810	@:
1811$(single-no-ko): descend
1812	@:
1813
1814ifeq ($(KBUILD_EXTMOD),)
1815# For the single build of in-tree modules, use a temporary file to avoid
1816# the situation of modules_install installing an invalid modules.order.
1817MODORDER := .modules.tmp
1818endif
1819
1820PHONY += single_modpost
1821single_modpost: $(single-no-ko) modules_prepare
1822	$(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$m;) } > $(MODORDER)
1823	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1824
1825KBUILD_MODULES := 1
1826
1827export KBUILD_SINGLE_TARGETS := $(addprefix $(extmod_prefix), $(single-no-ko))
1828
1829# trim unrelated directories
1830build-dirs := $(foreach d, $(build-dirs), \
1831			$(if $(filter $(d)/%, $(KBUILD_SINGLE_TARGETS)), $(d)))
1832
1833endif
1834
1835ifndef CONFIG_MODULES
1836KBUILD_MODULES :=
1837endif
1838
1839# Handle descending into subdirectories listed in $(build-dirs)
1840# Preset locale variables to speed up the build process. Limit locale
1841# tweaks to this spot to avoid wrong language settings when running
1842# make menuconfig etc.
1843# Error messages still appears in the original language
1844PHONY += descend $(build-dirs)
1845descend: $(build-dirs)
1846$(build-dirs): prepare
1847	$(Q)$(MAKE) $(build)=$@ \
1848	single-build=$(if $(filter-out $@/, $(filter $@/%, $(KBUILD_SINGLE_TARGETS))),1) \
1849	need-builtin=1 need-modorder=1
1850
1851clean-dirs := $(addprefix _clean_, $(clean-dirs))
1852PHONY += $(clean-dirs) clean
1853$(clean-dirs):
1854	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1855
1856clean: $(clean-dirs)
1857	$(call cmd,rmfiles)
1858	@find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1859		\( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1860		-o -name '*.ko.*' \
1861		-o -name '*.dtb' -o -name '*.dtbo' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1862		-o -name '*.dwo' -o -name '*.lst' \
1863		-o -name '*.su' -o -name '*.mod' \
1864		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1865		-o -name '*.lex.c' -o -name '*.tab.[ch]' \
1866		-o -name '*.asn1.[ch]' \
1867		-o -name '*.symtypes' -o -name 'modules.order' \
1868		-o -name '.tmp_*.o.*' \
1869		-o -name '*.c.[012]*.*' \
1870		-o -name '*.ll' \
1871		-o -name '*.gcno' \
1872		-o -name '*.*.symversions' \) -type f -print | xargs rm -f
1873
1874# Generate tags for editors
1875# ---------------------------------------------------------------------------
1876quiet_cmd_tags = GEN     $@
1877      cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1878
1879tags TAGS cscope gtags: FORCE
1880	$(call cmd,tags)
1881
1882# Script to generate missing namespace dependencies
1883# ---------------------------------------------------------------------------
1884
1885PHONY += nsdeps
1886nsdeps: export KBUILD_NSDEPS=1
1887nsdeps: modules
1888	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1889
1890# Clang Tooling
1891# ---------------------------------------------------------------------------
1892
1893quiet_cmd_gen_compile_commands = GEN     $@
1894      cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
1895
1896$(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
1897	$(if $(KBUILD_EXTMOD),,$(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)) \
1898	$(if $(CONFIG_MODULES), $(MODORDER)) FORCE
1899	$(call if_changed,gen_compile_commands)
1900
1901targets += $(extmod_prefix)compile_commands.json
1902
1903PHONY += clang-tidy clang-analyzer
1904
1905ifdef CONFIG_CC_IS_CLANG
1906quiet_cmd_clang_tools = CHECK   $<
1907      cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
1908
1909clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
1910	$(call cmd,clang_tools)
1911else
1912clang-tidy clang-analyzer:
1913	@echo "$@ requires CC=clang" >&2
1914	@false
1915endif
1916
1917# Scripts to check various things for consistency
1918# ---------------------------------------------------------------------------
1919
1920PHONY += includecheck versioncheck coccicheck export_report
1921
1922includecheck:
1923	find $(srctree)/* $(RCS_FIND_IGNORE) \
1924		-name '*.[hcS]' -type f -print | sort \
1925		| xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1926
1927versioncheck:
1928	find $(srctree)/* $(RCS_FIND_IGNORE) \
1929		-name '*.[hcS]' -type f -print | sort \
1930		| xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1931
1932coccicheck:
1933	$(Q)$(BASH) $(srctree)/scripts/$@
1934
1935export_report:
1936	$(PERL) $(srctree)/scripts/export_report.pl
1937
1938PHONY += checkstack kernelrelease kernelversion image_name
1939
1940# UML needs a little special treatment here.  It wants to use the host
1941# toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
1942# else wants $(ARCH), including people doing cross-builds, which means
1943# that $(SUBARCH) doesn't work here.
1944ifeq ($(ARCH), um)
1945CHECKSTACK_ARCH := $(SUBARCH)
1946else
1947CHECKSTACK_ARCH := $(ARCH)
1948endif
1949checkstack:
1950	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1951	$(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1952
1953kernelrelease:
1954	@echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1955
1956kernelversion:
1957	@echo $(KERNELVERSION)
1958
1959image_name:
1960	@echo $(KBUILD_IMAGE)
1961
1962# Clear a bunch of variables before executing the submake
1963
1964ifeq ($(quiet),silent_)
1965tools_silent=s
1966endif
1967
1968tools/: FORCE
1969	$(Q)mkdir -p $(objtree)/tools
1970	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1971
1972tools/%: FORCE
1973	$(Q)mkdir -p $(objtree)/tools
1974	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1975
1976quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
1977      cmd_rmfiles = rm -rf $(rm-files)
1978
1979# read saved command lines for existing targets
1980existing-targets := $(wildcard $(sort $(targets)))
1981
1982-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
1983
1984endif # config-build
1985endif # mixed-build
1986endif # need-sub-make
1987
1988PHONY += FORCE
1989FORCE:
1990
1991# Declare the contents of the PHONY variable as phony.  We keep that
1992# information in a variable so we can use it in if_changed and friends.
1993.PHONY: $(PHONY)
1994