xref: /openbmc/linux/Makefile (revision 9009b455811b0fa1f6b0adfa94db136984db5a38)
1# SPDX-License-Identifier: GPL-2.0
2VERSION = 5
3PATCHLEVEL = 12
4SUBLEVEL = 0
5EXTRAVERSION =
6NAME = Frozen Wasteland
7
8# *DOCUMENTATION*
9# To see a list of typical targets execute "make help"
10# More info can be located in ./README
11# Comments in this file are targeted only to the developer, do not
12# expect to learn how to build the kernel reading this file.
13
14$(if $(filter __%, $(MAKECMDGOALS)), \
15	$(error targets prefixed with '__' are only for internal use))
16
17# That's our default target when none is given on the command line
18PHONY := __all
19__all:
20
21# We are using a recursive build, so we need to do a little thinking
22# to get the ordering right.
23#
24# Most importantly: sub-Makefiles should only ever modify files in
25# their own directory. If in some directory we have a dependency on
26# a file in another dir (which doesn't happen often, but it's often
27# unavoidable when linking the built-in.a targets which finally
28# turn into vmlinux), we will call a sub make in that other dir, and
29# after that we are sure that everything which is in that other dir
30# is now up to date.
31#
32# The only cases where we need to modify files which have global
33# effects are thus separated out and done before the recursive
34# descending is started. They are now explicitly listed as the
35# prepare rule.
36
37ifneq ($(sub_make_done),1)
38
39# Do not use make's built-in rules and variables
40# (this increases performance and avoids hard-to-debug behaviour)
41MAKEFLAGS += -rR
42
43# Avoid funny character set dependencies
44unexport LC_ALL
45LC_COLLATE=C
46LC_NUMERIC=C
47export LC_COLLATE LC_NUMERIC
48
49# Avoid interference with shell env settings
50unexport GREP_OPTIONS
51
52# Beautify output
53# ---------------------------------------------------------------------------
54#
55# Normally, we echo the whole command before executing it. By making
56# that echo $($(quiet)$(cmd)), we now have the possibility to set
57# $(quiet) to choose other forms of output instead, e.g.
58#
59#         quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
60#         cmd_cc_o_c       = $(CC) $(c_flags) -c -o $@ $<
61#
62# If $(quiet) is empty, the whole command will be printed.
63# If it is set to "quiet_", only the short version will be printed.
64# If it is set to "silent_", nothing will be printed at all, since
65# the variable $(silent_cmd_cc_o_c) doesn't exist.
66#
67# A simple variant is to prefix commands with $(Q) - that's useful
68# for commands that shall be hidden in non-verbose mode.
69#
70#	$(Q)ln $@ :<
71#
72# If KBUILD_VERBOSE equals 0 then the above command will be hidden.
73# If KBUILD_VERBOSE equals 1 then the above command is displayed.
74# If KBUILD_VERBOSE equals 2 then give the reason why each target is rebuilt.
75#
76# To put more focus on warnings, be less verbose as default
77# Use 'make V=1' to see the full commands
78
79ifeq ("$(origin V)", "command line")
80  KBUILD_VERBOSE = $(V)
81endif
82ifndef KBUILD_VERBOSE
83  KBUILD_VERBOSE = 0
84endif
85
86ifeq ($(KBUILD_VERBOSE),1)
87  quiet =
88  Q =
89else
90  quiet=quiet_
91  Q = @
92endif
93
94# If the user is running make -s (silent mode), suppress echoing of
95# commands
96
97ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
98  quiet=silent_
99  KBUILD_VERBOSE = 0
100endif
101
102export quiet Q KBUILD_VERBOSE
103
104# Call a source code checker (by default, "sparse") as part of the
105# C compilation.
106#
107# Use 'make C=1' to enable checking of only re-compiled files.
108# Use 'make C=2' to enable checking of *all* source files, regardless
109# of whether they are re-compiled or not.
110#
111# See the file "Documentation/dev-tools/sparse.rst" for more details,
112# including where to get the "sparse" utility.
113
114ifeq ("$(origin C)", "command line")
115  KBUILD_CHECKSRC = $(C)
116endif
117ifndef KBUILD_CHECKSRC
118  KBUILD_CHECKSRC = 0
119endif
120
121export KBUILD_CHECKSRC
122
123# Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
124# directory of external module to build. Setting M= takes precedence.
125ifeq ("$(origin M)", "command line")
126  KBUILD_EXTMOD := $(M)
127endif
128
129$(if $(word 2, $(KBUILD_EXTMOD)), \
130	$(error building multiple external modules is not supported))
131
132export KBUILD_EXTMOD
133
134# Kbuild will save output files in the current working directory.
135# This does not need to match to the root of the kernel source tree.
136#
137# For example, you can do this:
138#
139#  cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
140#
141# If you want to save output files in a different location, there are
142# two syntaxes to specify it.
143#
144# 1) O=
145# Use "make O=dir/to/store/output/files/"
146#
147# 2) Set KBUILD_OUTPUT
148# Set the environment variable KBUILD_OUTPUT to point to the output directory.
149# export KBUILD_OUTPUT=dir/to/store/output/files/; make
150#
151# The O= assignment takes precedence over the KBUILD_OUTPUT environment
152# variable.
153
154# Do we want to change the working directory?
155ifeq ("$(origin O)", "command line")
156  KBUILD_OUTPUT := $(O)
157endif
158
159ifneq ($(KBUILD_OUTPUT),)
160# Make's built-in functions such as $(abspath ...), $(realpath ...) cannot
161# expand a shell special character '~'. We use a somewhat tedious way here.
162abs_objtree := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) && pwd)
163$(if $(abs_objtree),, \
164     $(error failed to create output directory "$(KBUILD_OUTPUT)"))
165
166# $(realpath ...) resolves symlinks
167abs_objtree := $(realpath $(abs_objtree))
168else
169abs_objtree := $(CURDIR)
170endif # ifneq ($(KBUILD_OUTPUT),)
171
172ifeq ($(abs_objtree),$(CURDIR))
173# Suppress "Entering directory ..." unless we are changing the work directory.
174MAKEFLAGS += --no-print-directory
175else
176need-sub-make := 1
177endif
178
179this-makefile := $(lastword $(MAKEFILE_LIST))
180abs_srctree := $(realpath $(dir $(this-makefile)))
181
182ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
183$(error source directory cannot contain spaces or colons)
184endif
185
186ifneq ($(abs_srctree),$(abs_objtree))
187# Look for make include files relative to root of kernel src
188#
189# This does not become effective immediately because MAKEFLAGS is re-parsed
190# once after the Makefile is read. We need to invoke sub-make.
191MAKEFLAGS += --include-dir=$(abs_srctree)
192need-sub-make := 1
193endif
194
195ifneq ($(filter 3.%,$(MAKE_VERSION)),)
196# 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
197# We need to invoke sub-make to avoid implicit rules in the top Makefile.
198need-sub-make := 1
199# Cancel implicit rules for this Makefile.
200$(this-makefile): ;
201endif
202
203export abs_srctree abs_objtree
204export sub_make_done := 1
205
206ifeq ($(need-sub-make),1)
207
208PHONY += $(MAKECMDGOALS) __sub-make
209
210$(filter-out $(this-makefile), $(MAKECMDGOALS)) __all: __sub-make
211	@:
212
213# Invoke a second make in the output directory, passing relevant variables
214__sub-make:
215	$(Q)$(MAKE) -C $(abs_objtree) -f $(abs_srctree)/Makefile $(MAKECMDGOALS)
216
217endif # need-sub-make
218endif # sub_make_done
219
220# We process the rest of the Makefile if this is the final invocation of make
221ifeq ($(need-sub-make),)
222
223# Do not print "Entering directory ...",
224# but we want to display it when entering to the output directory
225# so that IDEs/editors are able to understand relative filenames.
226MAKEFLAGS += --no-print-directory
227
228ifeq ($(abs_srctree),$(abs_objtree))
229        # building in the source tree
230        srctree := .
231	building_out_of_srctree :=
232else
233        ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
234                # building in a subdirectory of the source tree
235                srctree := ..
236        else
237                srctree := $(abs_srctree)
238        endif
239	building_out_of_srctree := 1
240endif
241
242ifneq ($(KBUILD_ABS_SRCTREE),)
243srctree := $(abs_srctree)
244endif
245
246objtree		:= .
247VPATH		:= $(srctree)
248
249export building_out_of_srctree srctree objtree VPATH
250
251# To make sure we do not include .config for any of the *config targets
252# catch them early, and hand them over to scripts/kconfig/Makefile
253# It is allowed to specify more targets when calling make, including
254# mixing *config targets and build targets.
255# For example 'make oldconfig all'.
256# Detect when mixed targets is specified, and make a second invocation
257# of make so .config is not included in this case either (for *config).
258
259version_h := include/generated/uapi/linux/version.h
260
261clean-targets := %clean mrproper cleandocs
262no-dot-config-targets := $(clean-targets) \
263			 cscope gtags TAGS tags help% %docs check% coccicheck \
264			 $(version_h) headers headers_% archheaders archscripts \
265			 %asm-generic kernelversion %src-pkg dt_binding_check \
266			 outputmakefile
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
407export cross_compiling :=
408ifneq ($(SRCARCH),$(SUBARCH))
409cross_compiling := 1
410endif
411
412KCONFIG_CONFIG	?= .config
413export KCONFIG_CONFIG
414
415# SHELL used by kbuild
416CONFIG_SHELL := sh
417
418HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
419HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
420HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
421
422ifneq ($(LLVM),)
423HOSTCC	= clang
424HOSTCXX	= clang++
425else
426HOSTCC	= gcc
427HOSTCXX	= g++
428endif
429
430export KBUILD_USERCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
431			      -O2 -fomit-frame-pointer -std=gnu89
432export KBUILD_USERLDFLAGS :=
433
434KBUILD_HOSTCFLAGS   := $(KBUILD_USERCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
435KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
436KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
437KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
438
439# Make variables (CC, etc...)
440CPP		= $(CC) -E
441ifneq ($(LLVM),)
442CC		= clang
443LD		= ld.lld
444AR		= llvm-ar
445NM		= llvm-nm
446OBJCOPY		= llvm-objcopy
447OBJDUMP		= llvm-objdump
448READELF		= llvm-readelf
449STRIP		= llvm-strip
450else
451CC		= $(CROSS_COMPILE)gcc
452LD		= $(CROSS_COMPILE)ld
453AR		= $(CROSS_COMPILE)ar
454NM		= $(CROSS_COMPILE)nm
455OBJCOPY		= $(CROSS_COMPILE)objcopy
456OBJDUMP		= $(CROSS_COMPILE)objdump
457READELF		= $(CROSS_COMPILE)readelf
458STRIP		= $(CROSS_COMPILE)strip
459endif
460PAHOLE		= pahole
461RESOLVE_BTFIDS	= $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
462LEX		= flex
463YACC		= bison
464AWK		= awk
465INSTALLKERNEL  := installkernel
466DEPMOD		= depmod
467PERL		= perl
468PYTHON3		= python3
469CHECK		= sparse
470BASH		= bash
471KGZIP		= gzip
472KBZIP2		= bzip2
473KLZOP		= lzop
474LZMA		= lzma
475LZ4		= lz4c
476XZ		= xz
477ZSTD		= zstd
478
479CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
480		  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
481NOSTDINC_FLAGS :=
482CFLAGS_MODULE   =
483AFLAGS_MODULE   =
484LDFLAGS_MODULE  =
485CFLAGS_KERNEL	=
486AFLAGS_KERNEL	=
487LDFLAGS_vmlinux =
488
489# Use USERINCLUDE when you must reference the UAPI directories only.
490USERINCLUDE    := \
491		-I$(srctree)/arch/$(SRCARCH)/include/uapi \
492		-I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
493		-I$(srctree)/include/uapi \
494		-I$(objtree)/include/generated/uapi \
495                -include $(srctree)/include/linux/compiler-version.h \
496                -include $(srctree)/include/linux/kconfig.h
497
498# Use LINUXINCLUDE when you must reference the include/ directory.
499# Needed to be compatible with the O= option
500LINUXINCLUDE    := \
501		-I$(srctree)/arch/$(SRCARCH)/include \
502		-I$(objtree)/arch/$(SRCARCH)/include/generated \
503		$(if $(building_out_of_srctree),-I$(srctree)/include) \
504		-I$(objtree)/include \
505		$(USERINCLUDE)
506
507KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
508KBUILD_CFLAGS   := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
509		   -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
510		   -Werror=implicit-function-declaration -Werror=implicit-int \
511		   -Werror=return-type -Wno-format-security \
512		   -std=gnu89
513KBUILD_CPPFLAGS := -D__KERNEL__
514KBUILD_AFLAGS_KERNEL :=
515KBUILD_CFLAGS_KERNEL :=
516KBUILD_AFLAGS_MODULE  := -DMODULE
517KBUILD_CFLAGS_MODULE  := -DMODULE
518KBUILD_LDFLAGS_MODULE :=
519KBUILD_LDFLAGS :=
520CLANG_FLAGS :=
521
522export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC
523export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
524export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
525export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
526export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
527
528export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
529export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
530export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
531export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
532export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
533
534# Files to ignore in find ... statements
535
536export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
537			  -name CVS -o -name .pc -o -name .hg -o -name .git \) \
538			  -prune -o
539export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
540			 --exclude CVS --exclude .pc --exclude .hg --exclude .git
541
542# ===========================================================================
543# Rules shared between *config targets and build targets
544
545# Basic helpers built in scripts/basic/
546PHONY += scripts_basic
547scripts_basic:
548	$(Q)$(MAKE) $(build)=scripts/basic
549	$(Q)rm -f .tmp_quiet_recordmcount
550
551PHONY += outputmakefile
552# Before starting out-of-tree build, make sure the source tree is clean.
553# outputmakefile generates a Makefile in the output directory, if using a
554# separate output directory. This allows convenient use of make in the
555# output directory.
556# At the same time when output Makefile generated, generate .gitignore to
557# ignore whole output directory
558outputmakefile:
559ifdef building_out_of_srctree
560	$(Q)if [ -f $(srctree)/.config -o \
561		 -d $(srctree)/include/config -o \
562		 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
563		echo >&2 "***"; \
564		echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
565		echo >&2 "*** in $(abs_srctree)";\
566		echo >&2 "***"; \
567		false; \
568	fi
569	$(Q)ln -fsn $(srctree) source
570	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile $(srctree)
571	$(Q)test -e .gitignore || \
572	{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
573endif
574
575# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
576# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
577# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
578# and from include/config/auto.conf.cmd to detect the compiler upgrade.
579CC_VERSION_TEXT = $(subst $(pound),,$(shell $(CC) --version 2>/dev/null | head -n 1))
580
581ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
582ifneq ($(CROSS_COMPILE),)
583CLANG_FLAGS	+= --target=$(notdir $(CROSS_COMPILE:%-=%))
584endif
585ifeq ($(LLVM_IAS),1)
586CLANG_FLAGS	+= -integrated-as
587else
588CLANG_FLAGS	+= -no-integrated-as
589GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
590CLANG_FLAGS	+= --prefix=$(GCC_TOOLCHAIN_DIR)$(notdir $(CROSS_COMPILE))
591endif
592CLANG_FLAGS	+= -Werror=unknown-warning-option
593KBUILD_CFLAGS	+= $(CLANG_FLAGS)
594KBUILD_AFLAGS	+= $(CLANG_FLAGS)
595export CLANG_FLAGS
596endif
597
598# Include this also for config targets because some architectures need
599# cc-cross-prefix to determine CROSS_COMPILE.
600ifdef need-compiler
601include $(srctree)/scripts/Makefile.compiler
602endif
603
604ifdef config-build
605# ===========================================================================
606# *config targets only - make sure prerequisites are updated, and descend
607# in scripts/kconfig to make the *config target
608
609# Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
610# KBUILD_DEFCONFIG may point out an alternative default configuration
611# used for 'make defconfig'
612include $(srctree)/arch/$(SRCARCH)/Makefile
613export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
614
615config: outputmakefile scripts_basic FORCE
616	$(Q)$(MAKE) $(build)=scripts/kconfig $@
617
618%config: outputmakefile scripts_basic FORCE
619	$(Q)$(MAKE) $(build)=scripts/kconfig $@
620
621else #!config-build
622# ===========================================================================
623# Build targets only - this includes vmlinux, arch specific targets, clean
624# targets and others. In general all targets except *config targets.
625
626# If building an external module we do not care about the all: rule
627# but instead __all depend on modules
628PHONY += all
629ifeq ($(KBUILD_EXTMOD),)
630__all: all
631else
632__all: modules
633endif
634
635# Decide whether to build built-in, modular, or both.
636# Normally, just do built-in.
637
638KBUILD_MODULES :=
639KBUILD_BUILTIN := 1
640
641# If we have only "make modules", don't compile built-in objects.
642ifeq ($(MAKECMDGOALS),modules)
643  KBUILD_BUILTIN :=
644endif
645
646# If we have "make <whatever> modules", compile modules
647# in addition to whatever we do anyway.
648# Just "make" or "make all" shall build modules as well
649
650ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
651  KBUILD_MODULES := 1
652endif
653
654ifeq ($(MAKECMDGOALS),)
655  KBUILD_MODULES := 1
656endif
657
658export KBUILD_MODULES KBUILD_BUILTIN
659
660ifdef need-config
661include include/config/auto.conf
662endif
663
664ifeq ($(KBUILD_EXTMOD),)
665# Objects we will link into vmlinux / subdirs we need to visit
666core-y		:= init/ usr/
667drivers-y	:= drivers/ sound/
668drivers-$(CONFIG_SAMPLES) += samples/
669drivers-$(CONFIG_NET) += net/
670drivers-y	+= virt/
671libs-y		:= lib/
672endif # KBUILD_EXTMOD
673
674# The all: target is the default when no target is given on the
675# command line.
676# This allow a user to issue only 'make' to build a kernel including modules
677# Defaults to vmlinux, but the arch makefile usually adds further targets
678all: vmlinux
679
680CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage \
681	$(call cc-option,-fno-tree-loop-im) \
682	$(call cc-disable-warning,maybe-uninitialized,)
683export CFLAGS_GCOV
684
685# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
686ifdef CONFIG_FUNCTION_TRACER
687  CC_FLAGS_FTRACE := -pg
688endif
689
690RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
691RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
692RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
693RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
694RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
695RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
696export RETPOLINE_CFLAGS
697export RETPOLINE_VDSO_CFLAGS
698
699include $(srctree)/arch/$(SRCARCH)/Makefile
700
701ifdef need-config
702ifdef may-sync-config
703# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
704# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
705# because some architectures define CROSS_COMPILE there.
706include include/config/auto.conf.cmd
707
708$(KCONFIG_CONFIG):
709	@echo >&2 '***'
710	@echo >&2 '*** Configuration file "$@" not found!'
711	@echo >&2 '***'
712	@echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
713	@echo >&2 '*** "make menuconfig" or "make xconfig").'
714	@echo >&2 '***'
715	@/bin/false
716
717# The actual configuration files used during the build are stored in
718# include/generated/ and include/config/. Update them if .config is newer than
719# include/config/auto.conf (which mirrors .config).
720#
721# This exploits the 'multi-target pattern rule' trick.
722# The syncconfig should be executed only once to make all the targets.
723# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
724quiet_cmd_syncconfig = SYNC    $@
725      cmd_syncconfig = $(MAKE) -f $(srctree)/Makefile syncconfig
726
727%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h: $(KCONFIG_CONFIG)
728	+$(call cmd,syncconfig)
729else # !may-sync-config
730# External modules and some install targets need include/generated/autoconf.h
731# and include/config/auto.conf but do not care if they are up-to-date.
732# Use auto.conf to trigger the test
733PHONY += include/config/auto.conf
734
735include/config/auto.conf:
736	$(Q)test -e include/generated/autoconf.h -a -e $@ || (		\
737	echo >&2;							\
738	echo >&2 "  ERROR: Kernel configuration is invalid.";		\
739	echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
740	echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";	\
741	echo >&2 ;							\
742	/bin/false)
743
744endif # may-sync-config
745endif # need-config
746
747KBUILD_CFLAGS	+= $(call cc-option,-fno-delete-null-pointer-checks,)
748KBUILD_CFLAGS	+= $(call cc-disable-warning,frame-address,)
749KBUILD_CFLAGS	+= $(call cc-disable-warning, format-truncation)
750KBUILD_CFLAGS	+= $(call cc-disable-warning, format-overflow)
751KBUILD_CFLAGS	+= $(call cc-disable-warning, address-of-packed-member)
752
753ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
754KBUILD_CFLAGS += -O2
755else ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3
756KBUILD_CFLAGS += -O3
757else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
758KBUILD_CFLAGS += -Os
759endif
760
761# Tell gcc to never replace conditional load with a non-conditional one
762KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
763KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
764
765ifdef CONFIG_READABLE_ASM
766# Disable optimizations that make assembler listings hard to read.
767# reorder blocks reorders the control in the function
768# ipa clone creates specialized cloned functions
769# partial inlining inlines only parts of functions
770KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
771                 $(call cc-option,-fno-ipa-cp-clone,) \
772                 $(call cc-option,-fno-partial-inlining)
773endif
774
775ifneq ($(CONFIG_FRAME_WARN),0)
776KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
777endif
778
779stackp-flags-y                                    := -fno-stack-protector
780stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
781stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
782
783KBUILD_CFLAGS += $(stackp-flags-y)
784
785ifdef CONFIG_CC_IS_CLANG
786KBUILD_CPPFLAGS += -Qunused-arguments
787KBUILD_CFLAGS += -Wno-format-invalid-specifier
788KBUILD_CFLAGS += -Wno-gnu
789# CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
790# source of a reference will be _MergedGlobals and not on of the whitelisted names.
791# See modpost pattern 2
792KBUILD_CFLAGS += -mno-global-merge
793else
794
795# Warn about unmarked fall-throughs in switch statement.
796# Disabled for clang while comment to attribute conversion happens and
797# https://github.com/ClangBuiltLinux/linux/issues/636 is discussed.
798KBUILD_CFLAGS += $(call cc-option,-Wimplicit-fallthrough,)
799endif
800
801# These warnings generated too much noise in a regular build.
802# Use make W=1 to enable them (see scripts/Makefile.extrawarn)
803KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
804
805KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
806ifdef CONFIG_FRAME_POINTER
807KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
808else
809# Some targets (ARM with Thumb2, for example), can't be built with frame
810# pointers.  For those, we don't have FUNCTION_TRACER automatically
811# select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
812# incompatible with -fomit-frame-pointer with current GCC, so we don't use
813# -fomit-frame-pointer with FUNCTION_TRACER.
814ifndef CONFIG_FUNCTION_TRACER
815KBUILD_CFLAGS	+= -fomit-frame-pointer
816endif
817endif
818
819# Initialize all stack variables with a 0xAA pattern.
820ifdef CONFIG_INIT_STACK_ALL_PATTERN
821KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
822endif
823
824# Initialize all stack variables with a zero value.
825ifdef CONFIG_INIT_STACK_ALL_ZERO
826# Future support for zero initialization is still being debated, see
827# https://bugs.llvm.org/show_bug.cgi?id=45497. These flags are subject to being
828# renamed or dropped.
829KBUILD_CFLAGS	+= -ftrivial-auto-var-init=zero
830KBUILD_CFLAGS	+= -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
831endif
832
833# While VLAs have been removed, GCC produces unreachable stack probes
834# for the randomize_kstack_offset feature. Disable it for all compilers.
835KBUILD_CFLAGS	+= $(call cc-option, -fno-stack-clash-protection)
836
837DEBUG_CFLAGS	:=
838
839# Workaround for GCC versions < 5.0
840# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61801
841ifdef CONFIG_CC_IS_GCC
842DEBUG_CFLAGS	+= $(call cc-ifversion, -lt, 0500, $(call cc-option, -fno-var-tracking-assignments))
843endif
844
845ifdef CONFIG_DEBUG_INFO
846
847ifdef CONFIG_DEBUG_INFO_SPLIT
848DEBUG_CFLAGS	+= -gsplit-dwarf
849else
850DEBUG_CFLAGS	+= -g
851endif
852
853ifneq ($(LLVM_IAS),1)
854KBUILD_AFLAGS	+= -Wa,-gdwarf-2
855endif
856
857ifndef CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT
858dwarf-version-$(CONFIG_DEBUG_INFO_DWARF4) := 4
859dwarf-version-$(CONFIG_DEBUG_INFO_DWARF5) := 5
860DEBUG_CFLAGS	+= -gdwarf-$(dwarf-version-y)
861endif
862
863ifdef CONFIG_DEBUG_INFO_REDUCED
864DEBUG_CFLAGS	+= $(call cc-option, -femit-struct-debug-baseonly) \
865		   $(call cc-option,-fno-var-tracking)
866endif
867
868ifdef CONFIG_DEBUG_INFO_COMPRESSED
869DEBUG_CFLAGS	+= -gz=zlib
870KBUILD_AFLAGS	+= -gz=zlib
871KBUILD_LDFLAGS	+= --compress-debug-sections=zlib
872endif
873
874endif # CONFIG_DEBUG_INFO
875
876KBUILD_CFLAGS += $(DEBUG_CFLAGS)
877export DEBUG_CFLAGS
878
879ifdef CONFIG_FUNCTION_TRACER
880ifdef CONFIG_FTRACE_MCOUNT_USE_CC
881  CC_FLAGS_FTRACE	+= -mrecord-mcount
882  ifdef CONFIG_HAVE_NOP_MCOUNT
883    ifeq ($(call cc-option-yn, -mnop-mcount),y)
884      CC_FLAGS_FTRACE	+= -mnop-mcount
885      CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
886    endif
887  endif
888endif
889ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
890  CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
891endif
892ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
893  ifdef CONFIG_HAVE_C_RECORDMCOUNT
894    BUILD_C_RECORDMCOUNT := y
895    export BUILD_C_RECORDMCOUNT
896  endif
897endif
898ifdef CONFIG_HAVE_FENTRY
899  ifeq ($(call cc-option-yn, -mfentry),y)
900    CC_FLAGS_FTRACE	+= -mfentry
901    CC_FLAGS_USING	+= -DCC_USING_FENTRY
902  endif
903endif
904export CC_FLAGS_FTRACE
905KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
906KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
907endif
908
909# We trigger additional mismatches with less inlining
910ifdef CONFIG_DEBUG_SECTION_MISMATCH
911KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
912endif
913
914ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
915KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
916LDFLAGS_vmlinux += --gc-sections
917endif
918
919ifdef CONFIG_SHADOW_CALL_STACK
920CC_FLAGS_SCS	:= -fsanitize=shadow-call-stack
921KBUILD_CFLAGS	+= $(CC_FLAGS_SCS)
922export CC_FLAGS_SCS
923endif
924
925ifdef CONFIG_LTO_CLANG
926ifdef CONFIG_LTO_CLANG_THIN
927CC_FLAGS_LTO	:= -flto=thin -fsplit-lto-unit
928KBUILD_LDFLAGS	+= --thinlto-cache-dir=$(extmod_prefix).thinlto-cache
929else
930CC_FLAGS_LTO	:= -flto
931endif
932CC_FLAGS_LTO	+= -fvisibility=hidden
933
934# Limit inlining across translation units to reduce binary size
935KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
936endif
937
938ifdef CONFIG_LTO
939KBUILD_CFLAGS	+= -fno-lto $(CC_FLAGS_LTO)
940KBUILD_AFLAGS	+= -fno-lto
941export CC_FLAGS_LTO
942endif
943
944ifdef CONFIG_CFI_CLANG
945CC_FLAGS_CFI	:= -fsanitize=cfi \
946		   -fsanitize-cfi-cross-dso \
947		   -fno-sanitize-cfi-canonical-jump-tables \
948		   -fno-sanitize-trap=cfi \
949		   -fno-sanitize-blacklist
950
951ifdef CONFIG_CFI_PERMISSIVE
952CC_FLAGS_CFI	+= -fsanitize-recover=cfi
953endif
954
955# If LTO flags are filtered out, we must also filter out CFI.
956CC_FLAGS_LTO	+= $(CC_FLAGS_CFI)
957KBUILD_CFLAGS	+= $(CC_FLAGS_CFI)
958export CC_FLAGS_CFI
959endif
960
961ifdef CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_32B
962KBUILD_CFLAGS += -falign-functions=32
963endif
964
965# arch Makefile may override CC so keep this after arch Makefile is included
966NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
967
968# warn about C99 declaration after statement
969KBUILD_CFLAGS += -Wdeclaration-after-statement
970
971# Variable Length Arrays (VLAs) should not be used anywhere in the kernel
972KBUILD_CFLAGS += -Wvla
973
974# disable pointer signed / unsigned warnings in gcc 4.0
975KBUILD_CFLAGS += -Wno-pointer-sign
976
977# disable stringop warnings in gcc 8+
978KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
979
980# We'll want to enable this eventually, but it's not going away for 5.7 at least
981KBUILD_CFLAGS += $(call cc-disable-warning, zero-length-bounds)
982KBUILD_CFLAGS += $(call cc-disable-warning, array-bounds)
983KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
984
985# Another good warning that we'll want to enable eventually
986KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
987
988# Enabled with W=2, disabled by default as noisy
989KBUILD_CFLAGS += $(call cc-disable-warning, maybe-uninitialized)
990
991# disable invalid "can't wrap" optimizations for signed / pointers
992KBUILD_CFLAGS	+= -fno-strict-overflow
993
994# Make sure -fstack-check isn't enabled (like gentoo apparently did)
995KBUILD_CFLAGS  += -fno-stack-check
996
997# conserve stack if available
998KBUILD_CFLAGS   += $(call cc-option,-fconserve-stack)
999
1000# Prohibit date/time macros, which would make the build non-deterministic
1001KBUILD_CFLAGS   += -Werror=date-time
1002
1003# enforce correct pointer usage
1004KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)
1005
1006# Require designated initializers for all marked structures
1007KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)
1008
1009# change __FILE__ to the relative path from the srctree
1010KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
1011
1012# include additional Makefiles when needed
1013include-y			:= scripts/Makefile.extrawarn
1014include-$(CONFIG_KASAN)		+= scripts/Makefile.kasan
1015include-$(CONFIG_KCSAN)		+= scripts/Makefile.kcsan
1016include-$(CONFIG_UBSAN)		+= scripts/Makefile.ubsan
1017include-$(CONFIG_KCOV)		+= scripts/Makefile.kcov
1018include-$(CONFIG_GCC_PLUGINS)	+= scripts/Makefile.gcc-plugins
1019
1020include $(addprefix $(srctree)/, $(include-y))
1021
1022# scripts/Makefile.gcc-plugins is intentionally included last.
1023# Do not add $(call cc-option,...) below this line. When you build the kernel
1024# from the clean source tree, the GCC plugins do not exist at this point.
1025
1026# Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
1027KBUILD_CPPFLAGS += $(KCPPFLAGS)
1028KBUILD_AFLAGS   += $(KAFLAGS)
1029KBUILD_CFLAGS   += $(KCFLAGS)
1030
1031KBUILD_LDFLAGS_MODULE += --build-id=sha1
1032LDFLAGS_vmlinux += --build-id=sha1
1033
1034ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1035LDFLAGS_vmlinux	+= $(call ld-option, -X,)
1036endif
1037
1038ifeq ($(CONFIG_RELR),y)
1039LDFLAGS_vmlinux	+= --pack-dyn-relocs=relr
1040endif
1041
1042# We never want expected sections to be placed heuristically by the
1043# linker. All sections should be explicitly named in the linker script.
1044ifdef CONFIG_LD_ORPHAN_WARN
1045LDFLAGS_vmlinux += --orphan-handling=warn
1046endif
1047
1048# Align the bit size of userspace programs with the kernel
1049KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1050KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1051
1052# make the checker run with the right architecture
1053CHECKFLAGS += --arch=$(ARCH)
1054
1055# insure the checker run with the right endianness
1056CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1057
1058# the checker needs the correct machine size
1059CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1060
1061# Default kernel image to build when no specific target is given.
1062# KBUILD_IMAGE may be overruled on the command line or
1063# set in the environment
1064# Also any assignments in arch/$(ARCH)/Makefile take precedence over
1065# this default value
1066export KBUILD_IMAGE ?= vmlinux
1067
1068#
1069# INSTALL_PATH specifies where to place the updated kernel and system map
1070# images. Default is /boot, but you can set it to other values
1071export	INSTALL_PATH ?= /boot
1072
1073#
1074# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1075# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1076# an argument if needed. Otherwise it defaults to the kernel install path
1077#
1078export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1079
1080#
1081# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1082# relocations required by build roots.  This is not defined in the
1083# makefile but the argument can be passed to make if needed.
1084#
1085
1086MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1087export MODLIB
1088
1089HOST_LIBELF_LIBS = $(shell pkg-config libelf --libs 2>/dev/null || echo -lelf)
1090
1091has_libelf = $(call try-run,\
1092               echo "int main() {}" | $(HOSTCC) $(KBUILD_HOSTLDFLAGS) -xc -o /dev/null $(HOST_LIBELF_LIBS) -,1,0)
1093
1094ifdef CONFIG_STACK_VALIDATION
1095  ifeq ($(has_libelf),1)
1096    objtool_target := tools/objtool FORCE
1097  else
1098    SKIP_STACK_VALIDATION := 1
1099    export SKIP_STACK_VALIDATION
1100  endif
1101endif
1102
1103PHONY += resolve_btfids_clean
1104
1105resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1106
1107# tools/bpf/resolve_btfids directory might not exist
1108# in output directory, skip its clean in that case
1109resolve_btfids_clean:
1110ifneq ($(wildcard $(resolve_btfids_O)),)
1111	$(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1112endif
1113
1114ifdef CONFIG_BPF
1115ifdef CONFIG_DEBUG_INFO_BTF
1116  ifeq ($(has_libelf),1)
1117    resolve_btfids_target := tools/bpf/resolve_btfids FORCE
1118  else
1119    ERROR_RESOLVE_BTFIDS := 1
1120  endif
1121endif # CONFIG_DEBUG_INFO_BTF
1122endif # CONFIG_BPF
1123
1124PHONY += prepare0
1125
1126export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
1127export MODORDER := $(extmod_prefix)modules.order
1128export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
1129
1130ifeq ($(KBUILD_EXTMOD),)
1131core-y		+= kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
1132
1133vmlinux-dirs	:= $(patsubst %/,%,$(filter %/, \
1134		     $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
1135		     $(libs-y) $(libs-m)))
1136
1137vmlinux-alldirs	:= $(sort $(vmlinux-dirs) Documentation \
1138		     $(patsubst %/,%,$(filter %/, $(core-) \
1139			$(drivers-) $(libs-))))
1140
1141subdir-modorder := $(addsuffix modules.order,$(filter %/, \
1142			$(core-y) $(core-m) $(libs-y) $(libs-m) \
1143			$(drivers-y) $(drivers-m)))
1144
1145build-dirs	:= $(vmlinux-dirs)
1146clean-dirs	:= $(vmlinux-alldirs)
1147
1148# Externally visible symbols (used by link-vmlinux.sh)
1149KBUILD_VMLINUX_OBJS := $(head-y) $(patsubst %/,%/built-in.a, $(core-y))
1150KBUILD_VMLINUX_OBJS += $(addsuffix built-in.a, $(filter %/, $(libs-y)))
1151ifdef CONFIG_MODULES
1152KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1153KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1154else
1155KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1156endif
1157KBUILD_VMLINUX_OBJS += $(patsubst %/,%/built-in.a, $(drivers-y))
1158
1159export KBUILD_VMLINUX_OBJS KBUILD_VMLINUX_LIBS
1160export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1161# used by scripts/Makefile.package
1162export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) LICENSES arch include scripts tools)
1163
1164vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
1165
1166# Recurse until adjust_autoksyms.sh is satisfied
1167PHONY += autoksyms_recursive
1168ifdef CONFIG_TRIM_UNUSED_KSYMS
1169# For the kernel to actually contain only the needed exported symbols,
1170# we have to build modules as well to determine what those symbols are.
1171# (this can be evaluated only once include/config/auto.conf has been included)
1172KBUILD_MODULES := 1
1173
1174autoksyms_recursive: descend modules.order
1175	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1176	  "$(MAKE) -f $(srctree)/Makefile vmlinux"
1177endif
1178
1179autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1180
1181quiet_cmd_autoksyms_h = GEN     $@
1182      cmd_autoksyms_h = mkdir -p $(dir $@); \
1183			$(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@
1184
1185$(autoksyms_h):
1186	$(call cmd,autoksyms_h)
1187
1188ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1189
1190# Final link of vmlinux with optional arch pass after final link
1191cmd_link-vmlinux =                                                 \
1192	$(CONFIG_SHELL) $< "$(LD)" "$(KBUILD_LDFLAGS)" "$(LDFLAGS_vmlinux)";    \
1193	$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1194
1195vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1196	+$(call if_changed_dep,link-vmlinux)
1197
1198targets := vmlinux
1199
1200# The actual objects are generated when descending,
1201# make sure no implicit rule kicks in
1202$(sort $(vmlinux-deps) $(subdir-modorder)): descend ;
1203
1204filechk_kernel.release = \
1205	echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1206
1207# Store (new) KERNELRELEASE string in include/config/kernel.release
1208include/config/kernel.release: FORCE
1209	$(call filechk,kernel.release)
1210
1211# Additional helpers built in scripts/
1212# Carefully list dependencies so we do not try to build scripts twice
1213# in parallel
1214PHONY += scripts
1215scripts: scripts_basic scripts_dtc
1216	$(Q)$(MAKE) $(build)=$(@)
1217
1218# Things we need to do before we recursively start building the kernel
1219# or the modules are listed in "prepare".
1220# A multi level approach is used. prepareN is processed before prepareN-1.
1221# archprepare is used in arch Makefiles and when processed asm symlink,
1222# version.h and scripts_basic is processed / created.
1223
1224PHONY += prepare archprepare
1225
1226archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1227	asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h \
1228	include/generated/autoconf.h remove-stale-files
1229
1230prepare0: archprepare
1231	$(Q)$(MAKE) $(build)=scripts/mod
1232	$(Q)$(MAKE) $(build)=.
1233
1234# All the preparing..
1235prepare: prepare0 prepare-objtool prepare-resolve_btfids
1236
1237PHONY += remove-stale-files
1238remove-stale-files:
1239	$(Q)$(srctree)/scripts/remove-stale-files
1240
1241# Support for using generic headers in asm-generic
1242asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1243
1244PHONY += asm-generic uapi-asm-generic
1245asm-generic: uapi-asm-generic
1246	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1247	generic=include/asm-generic
1248uapi-asm-generic:
1249	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1250	generic=include/uapi/asm-generic
1251
1252PHONY += prepare-objtool prepare-resolve_btfids
1253prepare-objtool: $(objtool_target)
1254ifeq ($(SKIP_STACK_VALIDATION),1)
1255ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
1256	@echo "error: Cannot generate __mcount_loc for CONFIG_DYNAMIC_FTRACE=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1257	@false
1258endif
1259ifdef CONFIG_UNWINDER_ORC
1260	@echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1261	@false
1262else
1263	@echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1264endif
1265endif
1266
1267prepare-resolve_btfids: $(resolve_btfids_target)
1268ifeq ($(ERROR_RESOLVE_BTFIDS),1)
1269	@echo "error: Cannot resolve BTF IDs for CONFIG_DEBUG_INFO_BTF, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1270	@false
1271endif
1272# Generate some files
1273# ---------------------------------------------------------------------------
1274
1275# KERNELRELEASE can change from a few different places, meaning version.h
1276# needs to be updated, so this check is forced on all builds
1277
1278uts_len := 64
1279define filechk_utsrelease.h
1280	if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1281	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1282	  exit 1;                                                         \
1283	fi;                                                               \
1284	echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1285endef
1286
1287define filechk_version.h
1288	if [ $(SUBLEVEL) -gt 255 ]; then                                 \
1289		echo \#define LINUX_VERSION_CODE $(shell                 \
1290		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1291	else                                                             \
1292		echo \#define LINUX_VERSION_CODE $(shell                 \
1293		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1294	fi;                                                              \
1295	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
1296	((c) > 255 ? 255 : (c)))';                                       \
1297	echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
1298	echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
1299	echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1300endef
1301
1302$(version_h): PATCHLEVEL := $(if $(PATCHLEVEL), $(PATCHLEVEL), 0)
1303$(version_h): SUBLEVEL := $(if $(SUBLEVEL), $(SUBLEVEL), 0)
1304$(version_h): FORCE
1305	$(call filechk,version.h)
1306
1307include/generated/utsrelease.h: include/config/kernel.release FORCE
1308	$(call filechk,utsrelease.h)
1309
1310PHONY += headerdep
1311headerdep:
1312	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1313	$(srctree)/scripts/headerdep.pl -I$(srctree)/include
1314
1315# ---------------------------------------------------------------------------
1316# Kernel headers
1317
1318#Default location for installed headers
1319export INSTALL_HDR_PATH = $(objtree)/usr
1320
1321quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1322      cmd_headers_install = \
1323	mkdir -p $(INSTALL_HDR_PATH); \
1324	rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1325	usr/include $(INSTALL_HDR_PATH)
1326
1327PHONY += headers_install
1328headers_install: headers
1329	$(call cmd,headers_install)
1330
1331PHONY += archheaders archscripts
1332
1333hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1334
1335PHONY += headers
1336headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1337	$(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1338	  $(error Headers not exportable for the $(SRCARCH) architecture))
1339	$(Q)$(MAKE) $(hdr-inst)=include/uapi
1340	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1341
1342# Deprecated. It is no-op now.
1343PHONY += headers_check
1344headers_check:
1345	@echo >&2 "=================== WARNING ==================="
1346	@echo >&2 "Since Linux 5.5, 'make headers_check' is no-op,"
1347	@echo >&2 "and will be removed after Linux 5.15 release."
1348	@echo >&2 "Please remove headers_check from your scripts."
1349	@echo >&2 "==============================================="
1350
1351ifdef CONFIG_HEADERS_INSTALL
1352prepare: headers
1353endif
1354
1355PHONY += scripts_unifdef
1356scripts_unifdef: scripts_basic
1357	$(Q)$(MAKE) $(build)=scripts scripts/unifdef
1358
1359# ---------------------------------------------------------------------------
1360# Kernel selftest
1361
1362PHONY += kselftest
1363kselftest:
1364	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1365
1366kselftest-%: FORCE
1367	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1368
1369PHONY += kselftest-merge
1370kselftest-merge:
1371	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1372	$(Q)find $(srctree)/tools/testing/selftests -name config | \
1373		xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1374	$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1375
1376# ---------------------------------------------------------------------------
1377# Devicetree files
1378
1379ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1380dtstree := arch/$(SRCARCH)/boot/dts
1381endif
1382
1383ifneq ($(dtstree),)
1384
1385%.dtb: include/config/kernel.release scripts_dtc
1386	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1387
1388%.dtbo: include/config/kernel.release scripts_dtc
1389	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1390
1391PHONY += dtbs dtbs_install dtbs_check
1392dtbs: include/config/kernel.release scripts_dtc
1393	$(Q)$(MAKE) $(build)=$(dtstree)
1394
1395ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1396export CHECK_DTBS=y
1397dtbs: dt_binding_check
1398endif
1399
1400dtbs_check: dtbs
1401
1402dtbs_install:
1403	$(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1404
1405ifdef CONFIG_OF_EARLY_FLATTREE
1406all: dtbs
1407endif
1408
1409endif
1410
1411PHONY += scripts_dtc
1412scripts_dtc: scripts_basic
1413	$(Q)$(MAKE) $(build)=scripts/dtc
1414
1415ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1416export CHECK_DT_BINDING=y
1417endif
1418
1419PHONY += dt_binding_check
1420dt_binding_check: scripts_dtc
1421	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1422
1423# ---------------------------------------------------------------------------
1424# Modules
1425
1426ifdef CONFIG_MODULES
1427
1428# By default, build modules as well
1429
1430all: modules
1431
1432# When we're building modules with modversions, we need to consider
1433# the built-in objects during the descend as well, in order to
1434# make sure the checksums are up to date before we record them.
1435ifdef CONFIG_MODVERSIONS
1436  KBUILD_BUILTIN := 1
1437endif
1438
1439# Build modules
1440#
1441# A module can be listed more than once in obj-m resulting in
1442# duplicate lines in modules.order files.  Those are removed
1443# using awk while concatenating to the final file.
1444
1445PHONY += modules
1446modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_check modules_prepare
1447
1448cmd_modules_order = $(AWK) '!x[$$0]++' $(real-prereqs) > $@
1449
1450modules.order: $(subdir-modorder) FORCE
1451	$(call if_changed,modules_order)
1452
1453targets += modules.order
1454
1455# Target to prepare building external modules
1456PHONY += modules_prepare
1457modules_prepare: prepare
1458	$(Q)$(MAKE) $(build)=scripts scripts/module.lds
1459
1460export modules_sign_only :=
1461
1462ifeq ($(CONFIG_MODULE_SIG),y)
1463PHONY += modules_sign
1464modules_sign: modules_install
1465	@:
1466
1467# modules_sign is a subset of modules_install.
1468# 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1469ifeq ($(filter modules_install,$(MAKECMDGOALS)),)
1470modules_sign_only := y
1471endif
1472endif
1473
1474modinst_pre :=
1475ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
1476modinst_pre := __modinst_pre
1477endif
1478
1479modules_install: $(modinst_pre)
1480PHONY += __modinst_pre
1481__modinst_pre:
1482	@rm -rf $(MODLIB)/kernel
1483	@rm -f $(MODLIB)/source
1484	@mkdir -p $(MODLIB)/kernel
1485	@ln -s $(abspath $(srctree)) $(MODLIB)/source
1486	@if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
1487		rm -f $(MODLIB)/build ; \
1488		ln -s $(CURDIR) $(MODLIB)/build ; \
1489	fi
1490	@sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order
1491	@cp -f modules.builtin $(MODLIB)/
1492	@cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
1493
1494endif # CONFIG_MODULES
1495
1496###
1497# Cleaning is done on three levels.
1498# make clean     Delete most generated files
1499#                Leave enough to build external modules
1500# make mrproper  Delete the current configuration, and all generated files
1501# make distclean Remove editor backup files, patch leftover files and the like
1502
1503# Directories & files removed with 'make clean'
1504CLEAN_FILES += include/ksym vmlinux.symvers modules-only.symvers \
1505	       modules.builtin modules.builtin.modinfo modules.nsdeps \
1506	       compile_commands.json .thinlto-cache
1507
1508# Directories & files removed with 'make mrproper'
1509MRPROPER_FILES += include/config include/generated          \
1510		  arch/$(SRCARCH)/include/generated .tmp_objdiff \
1511		  debian snap tar-install \
1512		  .config .config.old .version \
1513		  Module.symvers \
1514		  signing_key.pem signing_key.priv signing_key.x509	\
1515		  x509.genkey extra_certificates signing_key.x509.keyid	\
1516		  signing_key.x509.signer vmlinux-gdb.py \
1517		  *.spec
1518
1519# Directories & files removed with 'make distclean'
1520DISTCLEAN_FILES += tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS
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#
1548distclean: rm-files := $(wildcard $(DISTCLEAN_FILES))
1549
1550PHONY += distclean
1551
1552distclean: mrproper
1553	$(call cmd,rmfiles)
1554	@find $(srctree) $(RCS_FIND_IGNORE) \
1555		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1556		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
1557		-o -name 'core' \) \
1558		-type f -print | xargs rm -f
1559
1560
1561# Packaging of the kernel to various formats
1562# ---------------------------------------------------------------------------
1563
1564%src-pkg: FORCE
1565	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1566%pkg: include/config/kernel.release FORCE
1567	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1568
1569# Brief documentation of the typical targets used
1570# ---------------------------------------------------------------------------
1571
1572boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1573boards := $(sort $(notdir $(boards)))
1574board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1575board-dirs := $(sort $(notdir $(board-dirs:/=)))
1576
1577PHONY += help
1578help:
1579	@echo  'Cleaning targets:'
1580	@echo  '  clean		  - Remove most generated files but keep the config and'
1581	@echo  '                    enough build support to build external modules'
1582	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
1583	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
1584	@echo  ''
1585	@echo  'Configuration targets:'
1586	@$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1587	@echo  ''
1588	@echo  'Other generic targets:'
1589	@echo  '  all		  - Build all targets marked with [*]'
1590	@echo  '* vmlinux	  - Build the bare kernel'
1591	@echo  '* modules	  - Build all modules'
1592	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1593	@echo  '  dir/            - Build all files in dir and below'
1594	@echo  '  dir/file.[ois]  - Build specified target only'
1595	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1596	@echo  '                    (requires compiler support for LLVM assembly generation)'
1597	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1598	@echo  '                    (requires a recent binutils and recent build (System.map))'
1599	@echo  '  dir/file.ko     - Build module including final link'
1600	@echo  '  modules_prepare - Set up for building external modules'
1601	@echo  '  tags/TAGS	  - Generate tags file for editors'
1602	@echo  '  cscope	  - Generate cscope index'
1603	@echo  '  gtags           - Generate GNU GLOBAL index'
1604	@echo  '  kernelrelease	  - Output the release version string (use with make -s)'
1605	@echo  '  kernelversion	  - Output the version stored in Makefile (use with make -s)'
1606	@echo  '  image_name	  - Output the image name (use with make -s)'
1607	@echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1608	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1609	 echo  ''
1610	@echo  'Static analysers:'
1611	@echo  '  checkstack      - Generate a list of stack hogs'
1612	@echo  '  versioncheck    - Sanity check on version.h usage'
1613	@echo  '  includecheck    - Check for duplicate included header files'
1614	@echo  '  export_report   - List the usages of all exported symbols'
1615	@echo  '  headerdep       - Detect inclusion cycles in headers'
1616	@echo  '  coccicheck      - Check with Coccinelle'
1617	@echo  '  clang-analyzer  - Check with clang static analyzer'
1618	@echo  '  clang-tidy      - Check with clang-tidy'
1619	@echo  ''
1620	@echo  'Tools:'
1621	@echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1622	@echo  ''
1623	@echo  'Kernel selftest:'
1624	@echo  '  kselftest         - Build and run kernel selftest'
1625	@echo  '                      Build, install, and boot kernel before'
1626	@echo  '                      running kselftest on it'
1627	@echo  '                      Run as root for full coverage'
1628	@echo  '  kselftest-all     - Build kernel selftest'
1629	@echo  '  kselftest-install - Build and install kernel selftest'
1630	@echo  '  kselftest-clean   - Remove all generated kselftest files'
1631	@echo  '  kselftest-merge   - Merge all the config dependencies of'
1632	@echo  '		      kselftest to existing .config.'
1633	@echo  ''
1634	@$(if $(dtstree), \
1635		echo 'Devicetree:'; \
1636		echo '* dtbs             - Build device tree blobs for enabled boards'; \
1637		echo '  dtbs_install     - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1638		echo '  dt_binding_check - Validate device tree binding documents'; \
1639		echo '  dtbs_check       - Validate device tree source files';\
1640		echo '')
1641
1642	@echo 'Userspace tools targets:'
1643	@echo '  use "make tools/help"'
1644	@echo '  or  "cd tools; make help"'
1645	@echo  ''
1646	@echo  'Kernel packaging:'
1647	@$(MAKE) -f $(srctree)/scripts/Makefile.package help
1648	@echo  ''
1649	@echo  'Documentation targets:'
1650	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1651	@echo  ''
1652	@echo  'Architecture specific targets ($(SRCARCH)):'
1653	@$(if $(archhelp),$(archhelp),\
1654		echo '  No architecture specific help defined for $(SRCARCH)')
1655	@echo  ''
1656	@$(if $(boards), \
1657		$(foreach b, $(boards), \
1658		printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1659		echo '')
1660	@$(if $(board-dirs), \
1661		$(foreach b, $(board-dirs), \
1662		printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1663		printf "  %-16s - Show all of the above\\n" help-boards; \
1664		echo '')
1665
1666	@echo  '  make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1667	@echo  '  make V=2   [targets] 2 => give reason for rebuild of target'
1668	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1669	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1670	@echo  '                       (sparse by default)'
1671	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1672	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1673	@echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
1674	@echo  '		1: warnings which may be relevant and do not occur too often'
1675	@echo  '		2: warnings which occur quite often but may still be relevant'
1676	@echo  '		3: more obscure warnings, can most likely be ignored'
1677	@echo  '		Multiple levels can be combined with W=12 or W=123'
1678	@echo  ''
1679	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
1680	@echo  'For further info see the ./README file'
1681
1682
1683help-board-dirs := $(addprefix help-,$(board-dirs))
1684
1685help-boards: $(help-board-dirs)
1686
1687boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1688
1689$(help-board-dirs): help-%:
1690	@echo  'Architecture specific targets ($(SRCARCH) $*):'
1691	@$(if $(boards-per-dir), \
1692		$(foreach b, $(boards-per-dir), \
1693		printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1694		echo '')
1695
1696
1697# Documentation targets
1698# ---------------------------------------------------------------------------
1699DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1700	       linkcheckdocs dochelp refcheckdocs
1701PHONY += $(DOC_TARGETS)
1702$(DOC_TARGETS):
1703	$(Q)$(MAKE) $(build)=Documentation $@
1704
1705# Misc
1706# ---------------------------------------------------------------------------
1707
1708PHONY += scripts_gdb
1709scripts_gdb: prepare0
1710	$(Q)$(MAKE) $(build)=scripts/gdb
1711	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1712
1713ifdef CONFIG_GDB_SCRIPTS
1714all: scripts_gdb
1715endif
1716
1717else # KBUILD_EXTMOD
1718
1719###
1720# External module support.
1721# When building external modules the kernel used as basis is considered
1722# read-only, and no consistency checks are made and the make
1723# system is not used on the basis kernel. If updates are required
1724# in the basis kernel ordinary make commands (without M=...) must
1725# be used.
1726#
1727# The following are the only valid targets when building external
1728# modules.
1729# make M=dir clean     Delete all automatically generated files
1730# make M=dir modules   Make all modules in specified dir
1731# make M=dir	       Same as 'make M=dir modules'
1732# make M=dir modules_install
1733#                      Install the modules built in the module directory
1734#                      Assumes install directory is already created
1735
1736# We are always building only modules.
1737KBUILD_BUILTIN :=
1738KBUILD_MODULES := 1
1739
1740build-dirs := $(KBUILD_EXTMOD)
1741$(MODORDER): descend
1742	@:
1743
1744compile_commands.json: $(extmod_prefix)compile_commands.json
1745PHONY += compile_commands.json
1746
1747clean-dirs := $(KBUILD_EXTMOD)
1748clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1749	$(KBUILD_EXTMOD)/compile_commands.json $(KBUILD_EXTMOD)/.thinlto-cache
1750
1751PHONY += help
1752help:
1753	@echo  '  Building external modules.'
1754	@echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1755	@echo  ''
1756	@echo  '  modules         - default target, build the module(s)'
1757	@echo  '  modules_install - install the module'
1758	@echo  '  clean           - remove generated files in module directory only'
1759	@echo  ''
1760
1761# no-op for external module builds
1762PHONY += prepare modules_prepare
1763
1764endif # KBUILD_EXTMOD
1765
1766# ---------------------------------------------------------------------------
1767# Modules
1768
1769PHONY += modules modules_install
1770
1771ifdef CONFIG_MODULES
1772
1773modules: modules_check
1774	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1775
1776PHONY += modules_check
1777modules_check: $(MODORDER)
1778	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1779
1780quiet_cmd_depmod = DEPMOD  $(MODLIB)
1781      cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1782                   $(KERNELRELEASE)
1783
1784modules_install:
1785	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1786	$(call cmd,depmod)
1787
1788else # CONFIG_MODULES
1789
1790# Modules not configured
1791# ---------------------------------------------------------------------------
1792
1793modules modules_install:
1794	@echo >&2 '***'
1795	@echo >&2 '*** The present kernel configuration has modules disabled.'
1796	@echo >&2 '*** To use the module feature, please run "make menuconfig" etc.'
1797	@echo >&2 '*** to enable CONFIG_MODULES.'
1798	@echo >&2 '***'
1799	@exit 1
1800
1801endif # CONFIG_MODULES
1802
1803# Single targets
1804# ---------------------------------------------------------------------------
1805# To build individual files in subdirectories, you can do like this:
1806#
1807#   make foo/bar/baz.s
1808#
1809# The supported suffixes for single-target are listed in 'single-targets'
1810#
1811# To build only under specific subdirectories, you can do like this:
1812#
1813#   make foo/bar/baz/
1814
1815ifdef single-build
1816
1817# .ko is special because modpost is needed
1818single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1819single-no-ko := $(sort $(patsubst %.ko,%.mod, $(MAKECMDGOALS)))
1820
1821$(single-ko): single_modpost
1822	@:
1823$(single-no-ko): descend
1824	@:
1825
1826ifeq ($(KBUILD_EXTMOD),)
1827# For the single build of in-tree modules, use a temporary file to avoid
1828# the situation of modules_install installing an invalid modules.order.
1829MODORDER := .modules.tmp
1830endif
1831
1832PHONY += single_modpost
1833single_modpost: $(single-no-ko) modules_prepare
1834	$(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$m;) } > $(MODORDER)
1835	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1836
1837KBUILD_MODULES := 1
1838
1839export KBUILD_SINGLE_TARGETS := $(addprefix $(extmod_prefix), $(single-no-ko))
1840
1841# trim unrelated directories
1842build-dirs := $(foreach d, $(build-dirs), \
1843			$(if $(filter $(d)/%, $(KBUILD_SINGLE_TARGETS)), $(d)))
1844
1845endif
1846
1847ifndef CONFIG_MODULES
1848KBUILD_MODULES :=
1849endif
1850
1851# Handle descending into subdirectories listed in $(build-dirs)
1852# Preset locale variables to speed up the build process. Limit locale
1853# tweaks to this spot to avoid wrong language settings when running
1854# make menuconfig etc.
1855# Error messages still appears in the original language
1856PHONY += descend $(build-dirs)
1857descend: $(build-dirs)
1858$(build-dirs): prepare
1859	$(Q)$(MAKE) $(build)=$@ \
1860	single-build=$(if $(filter-out $@/, $(filter $@/%, $(KBUILD_SINGLE_TARGETS))),1) \
1861	need-builtin=1 need-modorder=1
1862
1863clean-dirs := $(addprefix _clean_, $(clean-dirs))
1864PHONY += $(clean-dirs) clean
1865$(clean-dirs):
1866	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1867
1868clean: $(clean-dirs)
1869	$(call cmd,rmfiles)
1870	@find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1871		\( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1872		-o -name '*.ko.*' \
1873		-o -name '*.dtb' -o -name '*.dtbo' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1874		-o -name '*.dwo' -o -name '*.lst' \
1875		-o -name '*.su' -o -name '*.mod' \
1876		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1877		-o -name '*.lex.c' -o -name '*.tab.[ch]' \
1878		-o -name '*.asn1.[ch]' \
1879		-o -name '*.symtypes' -o -name 'modules.order' \
1880		-o -name '.tmp_*.o.*' \
1881		-o -name '*.c.[012]*.*' \
1882		-o -name '*.ll' \
1883		-o -name '*.gcno' \
1884		-o -name '*.*.symversions' \) -type f -print | xargs rm -f
1885
1886# Generate tags for editors
1887# ---------------------------------------------------------------------------
1888quiet_cmd_tags = GEN     $@
1889      cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1890
1891tags TAGS cscope gtags: FORCE
1892	$(call cmd,tags)
1893
1894# Script to generate missing namespace dependencies
1895# ---------------------------------------------------------------------------
1896
1897PHONY += nsdeps
1898nsdeps: export KBUILD_NSDEPS=1
1899nsdeps: modules
1900	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1901
1902# Clang Tooling
1903# ---------------------------------------------------------------------------
1904
1905quiet_cmd_gen_compile_commands = GEN     $@
1906      cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
1907
1908$(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
1909	$(if $(KBUILD_EXTMOD),,$(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)) \
1910	$(if $(CONFIG_MODULES), $(MODORDER)) FORCE
1911	$(call if_changed,gen_compile_commands)
1912
1913targets += $(extmod_prefix)compile_commands.json
1914
1915PHONY += clang-tidy clang-analyzer
1916
1917ifdef CONFIG_CC_IS_CLANG
1918quiet_cmd_clang_tools = CHECK   $<
1919      cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
1920
1921clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
1922	$(call cmd,clang_tools)
1923else
1924clang-tidy clang-analyzer:
1925	@echo "$@ requires CC=clang" >&2
1926	@false
1927endif
1928
1929# Scripts to check various things for consistency
1930# ---------------------------------------------------------------------------
1931
1932PHONY += includecheck versioncheck coccicheck export_report
1933
1934includecheck:
1935	find $(srctree)/* $(RCS_FIND_IGNORE) \
1936		-name '*.[hcS]' -type f -print | sort \
1937		| xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1938
1939versioncheck:
1940	find $(srctree)/* $(RCS_FIND_IGNORE) \
1941		-name '*.[hcS]' -type f -print | sort \
1942		| xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1943
1944coccicheck:
1945	$(Q)$(BASH) $(srctree)/scripts/$@
1946
1947export_report:
1948	$(PERL) $(srctree)/scripts/export_report.pl
1949
1950PHONY += checkstack kernelrelease kernelversion image_name
1951
1952# UML needs a little special treatment here.  It wants to use the host
1953# toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
1954# else wants $(ARCH), including people doing cross-builds, which means
1955# that $(SUBARCH) doesn't work here.
1956ifeq ($(ARCH), um)
1957CHECKSTACK_ARCH := $(SUBARCH)
1958else
1959CHECKSTACK_ARCH := $(ARCH)
1960endif
1961checkstack:
1962	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1963	$(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1964
1965kernelrelease:
1966	@echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1967
1968kernelversion:
1969	@echo $(KERNELVERSION)
1970
1971image_name:
1972	@echo $(KBUILD_IMAGE)
1973
1974# Clear a bunch of variables before executing the submake
1975
1976ifeq ($(quiet),silent_)
1977tools_silent=s
1978endif
1979
1980tools/: FORCE
1981	$(Q)mkdir -p $(objtree)/tools
1982	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1983
1984tools/%: FORCE
1985	$(Q)mkdir -p $(objtree)/tools
1986	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1987
1988quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
1989      cmd_rmfiles = rm -rf $(rm-files)
1990
1991# read saved command lines for existing targets
1992existing-targets := $(wildcard $(sort $(targets)))
1993
1994-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
1995
1996endif # config-build
1997endif # mixed-build
1998endif # need-sub-make
1999
2000PHONY += FORCE
2001FORCE:
2002
2003# Declare the contents of the PHONY variable as phony.  We keep that
2004# information in a variable so we can use it in if_changed and friends.
2005.PHONY: $(PHONY)
2006