xref: /openbmc/linux/Makefile (revision 28dce2c4)
1# SPDX-License-Identifier: GPL-2.0
2VERSION = 5
3PATCHLEVEL = 13
4SUBLEVEL = 0
5EXTRAVERSION = -rc2
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 ($(ARCH),sparc64)
399       SRCARCH := sparc
400endif
401
402export cross_compiling :=
403ifneq ($(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
931endif
932
933ifdef CONFIG_LTO
934KBUILD_CFLAGS	+= -fno-lto $(CC_FLAGS_LTO)
935KBUILD_AFLAGS	+= -fno-lto
936export CC_FLAGS_LTO
937endif
938
939ifdef CONFIG_CFI_CLANG
940CC_FLAGS_CFI	:= -fsanitize=cfi \
941		   -fsanitize-cfi-cross-dso \
942		   -fno-sanitize-cfi-canonical-jump-tables \
943		   -fno-sanitize-trap=cfi \
944		   -fno-sanitize-blacklist
945
946ifdef CONFIG_CFI_PERMISSIVE
947CC_FLAGS_CFI	+= -fsanitize-recover=cfi
948endif
949
950# If LTO flags are filtered out, we must also filter out CFI.
951CC_FLAGS_LTO	+= $(CC_FLAGS_CFI)
952KBUILD_CFLAGS	+= $(CC_FLAGS_CFI)
953export CC_FLAGS_CFI
954endif
955
956ifdef CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_32B
957KBUILD_CFLAGS += -falign-functions=32
958endif
959
960# arch Makefile may override CC so keep this after arch Makefile is included
961NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
962
963# warn about C99 declaration after statement
964KBUILD_CFLAGS += -Wdeclaration-after-statement
965
966# Variable Length Arrays (VLAs) should not be used anywhere in the kernel
967KBUILD_CFLAGS += -Wvla
968
969# disable pointer signed / unsigned warnings in gcc 4.0
970KBUILD_CFLAGS += -Wno-pointer-sign
971
972# disable stringop warnings in gcc 8+
973KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
974
975# We'll want to enable this eventually, but it's not going away for 5.7 at least
976KBUILD_CFLAGS += $(call cc-disable-warning, zero-length-bounds)
977KBUILD_CFLAGS += $(call cc-disable-warning, array-bounds)
978KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
979
980# Another good warning that we'll want to enable eventually
981KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
982
983# Enabled with W=2, disabled by default as noisy
984KBUILD_CFLAGS += $(call cc-disable-warning, maybe-uninitialized)
985
986# disable invalid "can't wrap" optimizations for signed / pointers
987KBUILD_CFLAGS	+= -fno-strict-overflow
988
989# Make sure -fstack-check isn't enabled (like gentoo apparently did)
990KBUILD_CFLAGS  += -fno-stack-check
991
992# conserve stack if available
993KBUILD_CFLAGS   += $(call cc-option,-fconserve-stack)
994
995# Prohibit date/time macros, which would make the build non-deterministic
996KBUILD_CFLAGS   += -Werror=date-time
997
998# enforce correct pointer usage
999KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)
1000
1001# Require designated initializers for all marked structures
1002KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)
1003
1004# change __FILE__ to the relative path from the srctree
1005KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
1006
1007# include additional Makefiles when needed
1008include-y			:= scripts/Makefile.extrawarn
1009include-$(CONFIG_KASAN)		+= scripts/Makefile.kasan
1010include-$(CONFIG_KCSAN)		+= scripts/Makefile.kcsan
1011include-$(CONFIG_UBSAN)		+= scripts/Makefile.ubsan
1012include-$(CONFIG_KCOV)		+= scripts/Makefile.kcov
1013include-$(CONFIG_GCC_PLUGINS)	+= scripts/Makefile.gcc-plugins
1014
1015include $(addprefix $(srctree)/, $(include-y))
1016
1017# scripts/Makefile.gcc-plugins is intentionally included last.
1018# Do not add $(call cc-option,...) below this line. When you build the kernel
1019# from the clean source tree, the GCC plugins do not exist at this point.
1020
1021# Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
1022KBUILD_CPPFLAGS += $(KCPPFLAGS)
1023KBUILD_AFLAGS   += $(KAFLAGS)
1024KBUILD_CFLAGS   += $(KCFLAGS)
1025
1026KBUILD_LDFLAGS_MODULE += --build-id=sha1
1027LDFLAGS_vmlinux += --build-id=sha1
1028
1029ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1030LDFLAGS_vmlinux	+= $(call ld-option, -X,)
1031endif
1032
1033ifeq ($(CONFIG_RELR),y)
1034LDFLAGS_vmlinux	+= --pack-dyn-relocs=relr
1035endif
1036
1037# We never want expected sections to be placed heuristically by the
1038# linker. All sections should be explicitly named in the linker script.
1039ifdef CONFIG_LD_ORPHAN_WARN
1040LDFLAGS_vmlinux += --orphan-handling=warn
1041endif
1042
1043# Align the bit size of userspace programs with the kernel
1044KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1045KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1046
1047# make the checker run with the right architecture
1048CHECKFLAGS += --arch=$(ARCH)
1049
1050# insure the checker run with the right endianness
1051CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1052
1053# the checker needs the correct machine size
1054CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1055
1056# Default kernel image to build when no specific target is given.
1057# KBUILD_IMAGE may be overruled on the command line or
1058# set in the environment
1059# Also any assignments in arch/$(ARCH)/Makefile take precedence over
1060# this default value
1061export KBUILD_IMAGE ?= vmlinux
1062
1063#
1064# INSTALL_PATH specifies where to place the updated kernel and system map
1065# images. Default is /boot, but you can set it to other values
1066export	INSTALL_PATH ?= /boot
1067
1068#
1069# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1070# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1071# an argument if needed. Otherwise it defaults to the kernel install path
1072#
1073export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1074
1075#
1076# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1077# relocations required by build roots.  This is not defined in the
1078# makefile but the argument can be passed to make if needed.
1079#
1080
1081MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1082export MODLIB
1083
1084HOST_LIBELF_LIBS = $(shell pkg-config libelf --libs 2>/dev/null || echo -lelf)
1085
1086has_libelf = $(call try-run,\
1087               echo "int main() {}" | $(HOSTCC) $(KBUILD_HOSTLDFLAGS) -xc -o /dev/null $(HOST_LIBELF_LIBS) -,1,0)
1088
1089ifdef CONFIG_STACK_VALIDATION
1090  ifeq ($(has_libelf),1)
1091    objtool_target := tools/objtool FORCE
1092  else
1093    SKIP_STACK_VALIDATION := 1
1094    export SKIP_STACK_VALIDATION
1095  endif
1096endif
1097
1098PHONY += resolve_btfids_clean
1099
1100resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1101
1102# tools/bpf/resolve_btfids directory might not exist
1103# in output directory, skip its clean in that case
1104resolve_btfids_clean:
1105ifneq ($(wildcard $(resolve_btfids_O)),)
1106	$(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1107endif
1108
1109ifdef CONFIG_BPF
1110ifdef CONFIG_DEBUG_INFO_BTF
1111  ifeq ($(has_libelf),1)
1112    resolve_btfids_target := tools/bpf/resolve_btfids FORCE
1113  else
1114    ERROR_RESOLVE_BTFIDS := 1
1115  endif
1116endif # CONFIG_DEBUG_INFO_BTF
1117endif # CONFIG_BPF
1118
1119PHONY += prepare0
1120
1121export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
1122export MODORDER := $(extmod_prefix)modules.order
1123export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
1124
1125ifeq ($(KBUILD_EXTMOD),)
1126core-y		+= kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
1127
1128vmlinux-dirs	:= $(patsubst %/,%,$(filter %/, \
1129		     $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
1130		     $(libs-y) $(libs-m)))
1131
1132vmlinux-alldirs	:= $(sort $(vmlinux-dirs) Documentation \
1133		     $(patsubst %/,%,$(filter %/, $(core-) \
1134			$(drivers-) $(libs-))))
1135
1136subdir-modorder := $(addsuffix modules.order,$(filter %/, \
1137			$(core-y) $(core-m) $(libs-y) $(libs-m) \
1138			$(drivers-y) $(drivers-m)))
1139
1140build-dirs	:= $(vmlinux-dirs)
1141clean-dirs	:= $(vmlinux-alldirs)
1142
1143# Externally visible symbols (used by link-vmlinux.sh)
1144KBUILD_VMLINUX_OBJS := $(head-y) $(patsubst %/,%/built-in.a, $(core-y))
1145KBUILD_VMLINUX_OBJS += $(addsuffix built-in.a, $(filter %/, $(libs-y)))
1146ifdef CONFIG_MODULES
1147KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1148KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1149else
1150KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1151endif
1152KBUILD_VMLINUX_OBJS += $(patsubst %/,%/built-in.a, $(drivers-y))
1153
1154export KBUILD_VMLINUX_OBJS KBUILD_VMLINUX_LIBS
1155export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1156# used by scripts/Makefile.package
1157export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) LICENSES arch include scripts tools)
1158
1159vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
1160
1161# Recurse until adjust_autoksyms.sh is satisfied
1162PHONY += autoksyms_recursive
1163ifdef CONFIG_TRIM_UNUSED_KSYMS
1164# For the kernel to actually contain only the needed exported symbols,
1165# we have to build modules as well to determine what those symbols are.
1166# (this can be evaluated only once include/config/auto.conf has been included)
1167KBUILD_MODULES := 1
1168
1169autoksyms_recursive: descend modules.order
1170	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1171	  "$(MAKE) -f $(srctree)/Makefile vmlinux"
1172endif
1173
1174autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1175
1176quiet_cmd_autoksyms_h = GEN     $@
1177      cmd_autoksyms_h = mkdir -p $(dir $@); \
1178			$(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@
1179
1180$(autoksyms_h):
1181	$(call cmd,autoksyms_h)
1182
1183ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1184
1185# Final link of vmlinux with optional arch pass after final link
1186cmd_link-vmlinux =                                                 \
1187	$(CONFIG_SHELL) $< "$(LD)" "$(KBUILD_LDFLAGS)" "$(LDFLAGS_vmlinux)";    \
1188	$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1189
1190vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1191	+$(call if_changed_dep,link-vmlinux)
1192
1193targets := vmlinux
1194
1195# The actual objects are generated when descending,
1196# make sure no implicit rule kicks in
1197$(sort $(vmlinux-deps) $(subdir-modorder)): descend ;
1198
1199filechk_kernel.release = \
1200	echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1201
1202# Store (new) KERNELRELEASE string in include/config/kernel.release
1203include/config/kernel.release: FORCE
1204	$(call filechk,kernel.release)
1205
1206# Additional helpers built in scripts/
1207# Carefully list dependencies so we do not try to build scripts twice
1208# in parallel
1209PHONY += scripts
1210scripts: scripts_basic scripts_dtc
1211	$(Q)$(MAKE) $(build)=$(@)
1212
1213# Things we need to do before we recursively start building the kernel
1214# or the modules are listed in "prepare".
1215# A multi level approach is used. prepareN is processed before prepareN-1.
1216# archprepare is used in arch Makefiles and when processed asm symlink,
1217# version.h and scripts_basic is processed / created.
1218
1219PHONY += prepare archprepare
1220
1221archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1222	asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h \
1223	include/generated/autoconf.h remove-stale-files
1224
1225prepare0: archprepare
1226	$(Q)$(MAKE) $(build)=scripts/mod
1227	$(Q)$(MAKE) $(build)=.
1228
1229# All the preparing..
1230prepare: prepare0 prepare-objtool prepare-resolve_btfids
1231
1232PHONY += remove-stale-files
1233remove-stale-files:
1234	$(Q)$(srctree)/scripts/remove-stale-files
1235
1236# Support for using generic headers in asm-generic
1237asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1238
1239PHONY += asm-generic uapi-asm-generic
1240asm-generic: uapi-asm-generic
1241	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1242	generic=include/asm-generic
1243uapi-asm-generic:
1244	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1245	generic=include/uapi/asm-generic
1246
1247PHONY += prepare-objtool prepare-resolve_btfids
1248prepare-objtool: $(objtool_target)
1249ifeq ($(SKIP_STACK_VALIDATION),1)
1250ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
1251	@echo "error: Cannot generate __mcount_loc for CONFIG_DYNAMIC_FTRACE=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1252	@false
1253endif
1254ifdef CONFIG_UNWINDER_ORC
1255	@echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1256	@false
1257else
1258	@echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1259endif
1260endif
1261
1262prepare-resolve_btfids: $(resolve_btfids_target)
1263ifeq ($(ERROR_RESOLVE_BTFIDS),1)
1264	@echo "error: Cannot resolve BTF IDs for CONFIG_DEBUG_INFO_BTF, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1265	@false
1266endif
1267# Generate some files
1268# ---------------------------------------------------------------------------
1269
1270# KERNELRELEASE can change from a few different places, meaning version.h
1271# needs to be updated, so this check is forced on all builds
1272
1273uts_len := 64
1274define filechk_utsrelease.h
1275	if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1276	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1277	  exit 1;                                                         \
1278	fi;                                                               \
1279	echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1280endef
1281
1282define filechk_version.h
1283	if [ $(SUBLEVEL) -gt 255 ]; then                                 \
1284		echo \#define LINUX_VERSION_CODE $(shell                 \
1285		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1286	else                                                             \
1287		echo \#define LINUX_VERSION_CODE $(shell                 \
1288		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1289	fi;                                                              \
1290	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
1291	((c) > 255 ? 255 : (c)))';                                       \
1292	echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
1293	echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
1294	echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1295endef
1296
1297$(version_h): PATCHLEVEL := $(if $(PATCHLEVEL), $(PATCHLEVEL), 0)
1298$(version_h): SUBLEVEL := $(if $(SUBLEVEL), $(SUBLEVEL), 0)
1299$(version_h): FORCE
1300	$(call filechk,version.h)
1301
1302include/generated/utsrelease.h: include/config/kernel.release FORCE
1303	$(call filechk,utsrelease.h)
1304
1305PHONY += headerdep
1306headerdep:
1307	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1308	$(srctree)/scripts/headerdep.pl -I$(srctree)/include
1309
1310# ---------------------------------------------------------------------------
1311# Kernel headers
1312
1313#Default location for installed headers
1314export INSTALL_HDR_PATH = $(objtree)/usr
1315
1316quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1317      cmd_headers_install = \
1318	mkdir -p $(INSTALL_HDR_PATH); \
1319	rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1320	usr/include $(INSTALL_HDR_PATH)
1321
1322PHONY += headers_install
1323headers_install: headers
1324	$(call cmd,headers_install)
1325
1326PHONY += archheaders archscripts
1327
1328hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1329
1330PHONY += headers
1331headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1332	$(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1333	  $(error Headers not exportable for the $(SRCARCH) architecture))
1334	$(Q)$(MAKE) $(hdr-inst)=include/uapi
1335	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1336
1337# Deprecated. It is no-op now.
1338PHONY += headers_check
1339headers_check:
1340	@echo >&2 "=================== WARNING ==================="
1341	@echo >&2 "Since Linux 5.5, 'make headers_check' is no-op,"
1342	@echo >&2 "and will be removed after Linux 5.15 release."
1343	@echo >&2 "Please remove headers_check from your scripts."
1344	@echo >&2 "==============================================="
1345
1346ifdef CONFIG_HEADERS_INSTALL
1347prepare: headers
1348endif
1349
1350PHONY += scripts_unifdef
1351scripts_unifdef: scripts_basic
1352	$(Q)$(MAKE) $(build)=scripts scripts/unifdef
1353
1354# ---------------------------------------------------------------------------
1355# Kernel selftest
1356
1357PHONY += kselftest
1358kselftest:
1359	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1360
1361kselftest-%: FORCE
1362	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1363
1364PHONY += kselftest-merge
1365kselftest-merge:
1366	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1367	$(Q)find $(srctree)/tools/testing/selftests -name config | \
1368		xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1369	$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1370
1371# ---------------------------------------------------------------------------
1372# Devicetree files
1373
1374ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1375dtstree := arch/$(SRCARCH)/boot/dts
1376endif
1377
1378ifneq ($(dtstree),)
1379
1380%.dtb: include/config/kernel.release scripts_dtc
1381	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1382
1383%.dtbo: include/config/kernel.release scripts_dtc
1384	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1385
1386PHONY += dtbs dtbs_install dtbs_check
1387dtbs: include/config/kernel.release scripts_dtc
1388	$(Q)$(MAKE) $(build)=$(dtstree)
1389
1390ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1391export CHECK_DTBS=y
1392dtbs: dt_binding_check
1393endif
1394
1395dtbs_check: dtbs
1396
1397dtbs_install:
1398	$(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1399
1400ifdef CONFIG_OF_EARLY_FLATTREE
1401all: dtbs
1402endif
1403
1404endif
1405
1406PHONY += scripts_dtc
1407scripts_dtc: scripts_basic
1408	$(Q)$(MAKE) $(build)=scripts/dtc
1409
1410ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1411export CHECK_DT_BINDING=y
1412endif
1413
1414PHONY += dt_binding_check
1415dt_binding_check: scripts_dtc
1416	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1417
1418# ---------------------------------------------------------------------------
1419# Modules
1420
1421ifdef CONFIG_MODULES
1422
1423# By default, build modules as well
1424
1425all: modules
1426
1427# When we're building modules with modversions, we need to consider
1428# the built-in objects during the descend as well, in order to
1429# make sure the checksums are up to date before we record them.
1430ifdef CONFIG_MODVERSIONS
1431  KBUILD_BUILTIN := 1
1432endif
1433
1434# Build modules
1435#
1436# A module can be listed more than once in obj-m resulting in
1437# duplicate lines in modules.order files.  Those are removed
1438# using awk while concatenating to the final file.
1439
1440PHONY += modules
1441modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_check modules_prepare
1442
1443cmd_modules_order = $(AWK) '!x[$$0]++' $(real-prereqs) > $@
1444
1445modules.order: $(subdir-modorder) FORCE
1446	$(call if_changed,modules_order)
1447
1448targets += modules.order
1449
1450# Target to prepare building external modules
1451PHONY += modules_prepare
1452modules_prepare: prepare
1453	$(Q)$(MAKE) $(build)=scripts scripts/module.lds
1454
1455export modules_sign_only :=
1456
1457ifeq ($(CONFIG_MODULE_SIG),y)
1458PHONY += modules_sign
1459modules_sign: modules_install
1460	@:
1461
1462# modules_sign is a subset of modules_install.
1463# 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1464ifeq ($(filter modules_install,$(MAKECMDGOALS)),)
1465modules_sign_only := y
1466endif
1467endif
1468
1469modinst_pre :=
1470ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
1471modinst_pre := __modinst_pre
1472endif
1473
1474modules_install: $(modinst_pre)
1475PHONY += __modinst_pre
1476__modinst_pre:
1477	@rm -rf $(MODLIB)/kernel
1478	@rm -f $(MODLIB)/source
1479	@mkdir -p $(MODLIB)/kernel
1480	@ln -s $(abspath $(srctree)) $(MODLIB)/source
1481	@if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
1482		rm -f $(MODLIB)/build ; \
1483		ln -s $(CURDIR) $(MODLIB)/build ; \
1484	fi
1485	@sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order
1486	@cp -f modules.builtin $(MODLIB)/
1487	@cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
1488
1489endif # CONFIG_MODULES
1490
1491###
1492# Cleaning is done on three levels.
1493# make clean     Delete most generated files
1494#                Leave enough to build external modules
1495# make mrproper  Delete the current configuration, and all generated files
1496# make distclean Remove editor backup files, patch leftover files and the like
1497
1498# Directories & files removed with 'make clean'
1499CLEAN_FILES += include/ksym vmlinux.symvers modules-only.symvers \
1500	       modules.builtin modules.builtin.modinfo modules.nsdeps \
1501	       compile_commands.json .thinlto-cache
1502
1503# Directories & files removed with 'make mrproper'
1504MRPROPER_FILES += include/config include/generated          \
1505		  arch/$(SRCARCH)/include/generated .tmp_objdiff \
1506		  debian snap tar-install \
1507		  .config .config.old .version \
1508		  Module.symvers \
1509		  certs/signing_key.pem certs/signing_key.x509 \
1510		  certs/x509.genkey \
1511		  vmlinux-gdb.py \
1512		  *.spec
1513
1514# clean - Delete most, but leave enough to build external modules
1515#
1516clean: rm-files := $(CLEAN_FILES)
1517
1518PHONY += archclean vmlinuxclean
1519
1520vmlinuxclean:
1521	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1522	$(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1523
1524clean: archclean vmlinuxclean resolve_btfids_clean
1525
1526# mrproper - Delete all generated files, including .config
1527#
1528mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1529mrproper-dirs      := $(addprefix _mrproper_,scripts)
1530
1531PHONY += $(mrproper-dirs) mrproper
1532$(mrproper-dirs):
1533	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1534
1535mrproper: clean $(mrproper-dirs)
1536	$(call cmd,rmfiles)
1537
1538# distclean
1539#
1540PHONY += distclean
1541
1542distclean: mrproper
1543	@find . $(RCS_FIND_IGNORE) \
1544		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1545		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
1546		-o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1547		-o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1548		-type f -print | xargs rm -f
1549
1550
1551# Packaging of the kernel to various formats
1552# ---------------------------------------------------------------------------
1553
1554%src-pkg: FORCE
1555	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1556%pkg: include/config/kernel.release FORCE
1557	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1558
1559# Brief documentation of the typical targets used
1560# ---------------------------------------------------------------------------
1561
1562boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1563boards := $(sort $(notdir $(boards)))
1564board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1565board-dirs := $(sort $(notdir $(board-dirs:/=)))
1566
1567PHONY += help
1568help:
1569	@echo  'Cleaning targets:'
1570	@echo  '  clean		  - Remove most generated files but keep the config and'
1571	@echo  '                    enough build support to build external modules'
1572	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
1573	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
1574	@echo  ''
1575	@echo  'Configuration targets:'
1576	@$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1577	@echo  ''
1578	@echo  'Other generic targets:'
1579	@echo  '  all		  - Build all targets marked with [*]'
1580	@echo  '* vmlinux	  - Build the bare kernel'
1581	@echo  '* modules	  - Build all modules'
1582	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1583	@echo  '  dir/            - Build all files in dir and below'
1584	@echo  '  dir/file.[ois]  - Build specified target only'
1585	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1586	@echo  '                    (requires compiler support for LLVM assembly generation)'
1587	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1588	@echo  '                    (requires a recent binutils and recent build (System.map))'
1589	@echo  '  dir/file.ko     - Build module including final link'
1590	@echo  '  modules_prepare - Set up for building external modules'
1591	@echo  '  tags/TAGS	  - Generate tags file for editors'
1592	@echo  '  cscope	  - Generate cscope index'
1593	@echo  '  gtags           - Generate GNU GLOBAL index'
1594	@echo  '  kernelrelease	  - Output the release version string (use with make -s)'
1595	@echo  '  kernelversion	  - Output the version stored in Makefile (use with make -s)'
1596	@echo  '  image_name	  - Output the image name (use with make -s)'
1597	@echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1598	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1599	 echo  ''
1600	@echo  'Static analysers:'
1601	@echo  '  checkstack      - Generate a list of stack hogs'
1602	@echo  '  versioncheck    - Sanity check on version.h usage'
1603	@echo  '  includecheck    - Check for duplicate included header files'
1604	@echo  '  export_report   - List the usages of all exported symbols'
1605	@echo  '  headerdep       - Detect inclusion cycles in headers'
1606	@echo  '  coccicheck      - Check with Coccinelle'
1607	@echo  '  clang-analyzer  - Check with clang static analyzer'
1608	@echo  '  clang-tidy      - Check with clang-tidy'
1609	@echo  ''
1610	@echo  'Tools:'
1611	@echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1612	@echo  ''
1613	@echo  'Kernel selftest:'
1614	@echo  '  kselftest         - Build and run kernel selftest'
1615	@echo  '                      Build, install, and boot kernel before'
1616	@echo  '                      running kselftest on it'
1617	@echo  '                      Run as root for full coverage'
1618	@echo  '  kselftest-all     - Build kernel selftest'
1619	@echo  '  kselftest-install - Build and install kernel selftest'
1620	@echo  '  kselftest-clean   - Remove all generated kselftest files'
1621	@echo  '  kselftest-merge   - Merge all the config dependencies of'
1622	@echo  '		      kselftest to existing .config.'
1623	@echo  ''
1624	@$(if $(dtstree), \
1625		echo 'Devicetree:'; \
1626		echo '* dtbs             - Build device tree blobs for enabled boards'; \
1627		echo '  dtbs_install     - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1628		echo '  dt_binding_check - Validate device tree binding documents'; \
1629		echo '  dtbs_check       - Validate device tree source files';\
1630		echo '')
1631
1632	@echo 'Userspace tools targets:'
1633	@echo '  use "make tools/help"'
1634	@echo '  or  "cd tools; make help"'
1635	@echo  ''
1636	@echo  'Kernel packaging:'
1637	@$(MAKE) -f $(srctree)/scripts/Makefile.package help
1638	@echo  ''
1639	@echo  'Documentation targets:'
1640	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1641	@echo  ''
1642	@echo  'Architecture specific targets ($(SRCARCH)):'
1643	@$(if $(archhelp),$(archhelp),\
1644		echo '  No architecture specific help defined for $(SRCARCH)')
1645	@echo  ''
1646	@$(if $(boards), \
1647		$(foreach b, $(boards), \
1648		printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1649		echo '')
1650	@$(if $(board-dirs), \
1651		$(foreach b, $(board-dirs), \
1652		printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1653		printf "  %-16s - Show all of the above\\n" help-boards; \
1654		echo '')
1655
1656	@echo  '  make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1657	@echo  '  make V=2   [targets] 2 => give reason for rebuild of target'
1658	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1659	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1660	@echo  '                       (sparse by default)'
1661	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1662	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1663	@echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
1664	@echo  '		1: warnings which may be relevant and do not occur too often'
1665	@echo  '		2: warnings which occur quite often but may still be relevant'
1666	@echo  '		3: more obscure warnings, can most likely be ignored'
1667	@echo  '		Multiple levels can be combined with W=12 or W=123'
1668	@echo  ''
1669	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
1670	@echo  'For further info see the ./README file'
1671
1672
1673help-board-dirs := $(addprefix help-,$(board-dirs))
1674
1675help-boards: $(help-board-dirs)
1676
1677boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1678
1679$(help-board-dirs): help-%:
1680	@echo  'Architecture specific targets ($(SRCARCH) $*):'
1681	@$(if $(boards-per-dir), \
1682		$(foreach b, $(boards-per-dir), \
1683		printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1684		echo '')
1685
1686
1687# Documentation targets
1688# ---------------------------------------------------------------------------
1689DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1690	       linkcheckdocs dochelp refcheckdocs
1691PHONY += $(DOC_TARGETS)
1692$(DOC_TARGETS):
1693	$(Q)$(MAKE) $(build)=Documentation $@
1694
1695# Misc
1696# ---------------------------------------------------------------------------
1697
1698PHONY += scripts_gdb
1699scripts_gdb: prepare0
1700	$(Q)$(MAKE) $(build)=scripts/gdb
1701	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1702
1703ifdef CONFIG_GDB_SCRIPTS
1704all: scripts_gdb
1705endif
1706
1707else # KBUILD_EXTMOD
1708
1709###
1710# External module support.
1711# When building external modules the kernel used as basis is considered
1712# read-only, and no consistency checks are made and the make
1713# system is not used on the basis kernel. If updates are required
1714# in the basis kernel ordinary make commands (without M=...) must be used.
1715
1716# We are always building only modules.
1717KBUILD_BUILTIN :=
1718KBUILD_MODULES := 1
1719
1720build-dirs := $(KBUILD_EXTMOD)
1721$(MODORDER): descend
1722	@:
1723
1724compile_commands.json: $(extmod_prefix)compile_commands.json
1725PHONY += compile_commands.json
1726
1727clean-dirs := $(KBUILD_EXTMOD)
1728clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1729	$(KBUILD_EXTMOD)/compile_commands.json $(KBUILD_EXTMOD)/.thinlto-cache
1730
1731PHONY += help
1732help:
1733	@echo  '  Building external modules.'
1734	@echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1735	@echo  ''
1736	@echo  '  modules         - default target, build the module(s)'
1737	@echo  '  modules_install - install the module'
1738	@echo  '  clean           - remove generated files in module directory only'
1739	@echo  ''
1740
1741# no-op for external module builds
1742PHONY += prepare modules_prepare
1743
1744endif # KBUILD_EXTMOD
1745
1746# ---------------------------------------------------------------------------
1747# Modules
1748
1749PHONY += modules modules_install
1750
1751ifdef CONFIG_MODULES
1752
1753modules: modules_check
1754	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1755
1756PHONY += modules_check
1757modules_check: $(MODORDER)
1758	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1759
1760quiet_cmd_depmod = DEPMOD  $(MODLIB)
1761      cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1762                   $(KERNELRELEASE)
1763
1764modules_install:
1765	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1766	$(call cmd,depmod)
1767
1768else # CONFIG_MODULES
1769
1770# Modules not configured
1771# ---------------------------------------------------------------------------
1772
1773modules modules_install:
1774	@echo >&2 '***'
1775	@echo >&2 '*** The present kernel configuration has modules disabled.'
1776	@echo >&2 '*** To use the module feature, please run "make menuconfig" etc.'
1777	@echo >&2 '*** to enable CONFIG_MODULES.'
1778	@echo >&2 '***'
1779	@exit 1
1780
1781endif # CONFIG_MODULES
1782
1783# Single targets
1784# ---------------------------------------------------------------------------
1785# To build individual files in subdirectories, you can do like this:
1786#
1787#   make foo/bar/baz.s
1788#
1789# The supported suffixes for single-target are listed in 'single-targets'
1790#
1791# To build only under specific subdirectories, you can do like this:
1792#
1793#   make foo/bar/baz/
1794
1795ifdef single-build
1796
1797# .ko is special because modpost is needed
1798single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1799single-no-ko := $(sort $(patsubst %.ko,%.mod, $(MAKECMDGOALS)))
1800
1801$(single-ko): single_modpost
1802	@:
1803$(single-no-ko): descend
1804	@:
1805
1806ifeq ($(KBUILD_EXTMOD),)
1807# For the single build of in-tree modules, use a temporary file to avoid
1808# the situation of modules_install installing an invalid modules.order.
1809MODORDER := .modules.tmp
1810endif
1811
1812PHONY += single_modpost
1813single_modpost: $(single-no-ko) modules_prepare
1814	$(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$m;) } > $(MODORDER)
1815	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1816
1817KBUILD_MODULES := 1
1818
1819export KBUILD_SINGLE_TARGETS := $(addprefix $(extmod_prefix), $(single-no-ko))
1820
1821# trim unrelated directories
1822build-dirs := $(foreach d, $(build-dirs), \
1823			$(if $(filter $(d)/%, $(KBUILD_SINGLE_TARGETS)), $(d)))
1824
1825endif
1826
1827ifndef CONFIG_MODULES
1828KBUILD_MODULES :=
1829endif
1830
1831# Handle descending into subdirectories listed in $(build-dirs)
1832# Preset locale variables to speed up the build process. Limit locale
1833# tweaks to this spot to avoid wrong language settings when running
1834# make menuconfig etc.
1835# Error messages still appears in the original language
1836PHONY += descend $(build-dirs)
1837descend: $(build-dirs)
1838$(build-dirs): prepare
1839	$(Q)$(MAKE) $(build)=$@ \
1840	single-build=$(if $(filter-out $@/, $(filter $@/%, $(KBUILD_SINGLE_TARGETS))),1) \
1841	need-builtin=1 need-modorder=1
1842
1843clean-dirs := $(addprefix _clean_, $(clean-dirs))
1844PHONY += $(clean-dirs) clean
1845$(clean-dirs):
1846	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1847
1848clean: $(clean-dirs)
1849	$(call cmd,rmfiles)
1850	@find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1851		\( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1852		-o -name '*.ko.*' \
1853		-o -name '*.dtb' -o -name '*.dtbo' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1854		-o -name '*.dwo' -o -name '*.lst' \
1855		-o -name '*.su' -o -name '*.mod' \
1856		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1857		-o -name '*.lex.c' -o -name '*.tab.[ch]' \
1858		-o -name '*.asn1.[ch]' \
1859		-o -name '*.symtypes' -o -name 'modules.order' \
1860		-o -name '.tmp_*.o.*' \
1861		-o -name '*.c.[012]*.*' \
1862		-o -name '*.ll' \
1863		-o -name '*.gcno' \
1864		-o -name '*.*.symversions' \) -type f -print | xargs rm -f
1865
1866# Generate tags for editors
1867# ---------------------------------------------------------------------------
1868quiet_cmd_tags = GEN     $@
1869      cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1870
1871tags TAGS cscope gtags: FORCE
1872	$(call cmd,tags)
1873
1874# Script to generate missing namespace dependencies
1875# ---------------------------------------------------------------------------
1876
1877PHONY += nsdeps
1878nsdeps: export KBUILD_NSDEPS=1
1879nsdeps: modules
1880	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1881
1882# Clang Tooling
1883# ---------------------------------------------------------------------------
1884
1885quiet_cmd_gen_compile_commands = GEN     $@
1886      cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
1887
1888$(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
1889	$(if $(KBUILD_EXTMOD),,$(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)) \
1890	$(if $(CONFIG_MODULES), $(MODORDER)) FORCE
1891	$(call if_changed,gen_compile_commands)
1892
1893targets += $(extmod_prefix)compile_commands.json
1894
1895PHONY += clang-tidy clang-analyzer
1896
1897ifdef CONFIG_CC_IS_CLANG
1898quiet_cmd_clang_tools = CHECK   $<
1899      cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
1900
1901clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
1902	$(call cmd,clang_tools)
1903else
1904clang-tidy clang-analyzer:
1905	@echo "$@ requires CC=clang" >&2
1906	@false
1907endif
1908
1909# Scripts to check various things for consistency
1910# ---------------------------------------------------------------------------
1911
1912PHONY += includecheck versioncheck coccicheck export_report
1913
1914includecheck:
1915	find $(srctree)/* $(RCS_FIND_IGNORE) \
1916		-name '*.[hcS]' -type f -print | sort \
1917		| xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1918
1919versioncheck:
1920	find $(srctree)/* $(RCS_FIND_IGNORE) \
1921		-name '*.[hcS]' -type f -print | sort \
1922		| xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1923
1924coccicheck:
1925	$(Q)$(BASH) $(srctree)/scripts/$@
1926
1927export_report:
1928	$(PERL) $(srctree)/scripts/export_report.pl
1929
1930PHONY += checkstack kernelrelease kernelversion image_name
1931
1932# UML needs a little special treatment here.  It wants to use the host
1933# toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
1934# else wants $(ARCH), including people doing cross-builds, which means
1935# that $(SUBARCH) doesn't work here.
1936ifeq ($(ARCH), um)
1937CHECKSTACK_ARCH := $(SUBARCH)
1938else
1939CHECKSTACK_ARCH := $(ARCH)
1940endif
1941checkstack:
1942	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1943	$(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1944
1945kernelrelease:
1946	@echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1947
1948kernelversion:
1949	@echo $(KERNELVERSION)
1950
1951image_name:
1952	@echo $(KBUILD_IMAGE)
1953
1954# Clear a bunch of variables before executing the submake
1955
1956ifeq ($(quiet),silent_)
1957tools_silent=s
1958endif
1959
1960tools/: FORCE
1961	$(Q)mkdir -p $(objtree)/tools
1962	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1963
1964tools/%: FORCE
1965	$(Q)mkdir -p $(objtree)/tools
1966	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1967
1968quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
1969      cmd_rmfiles = rm -rf $(rm-files)
1970
1971# read saved command lines for existing targets
1972existing-targets := $(wildcard $(sort $(targets)))
1973
1974-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
1975
1976endif # config-build
1977endif # mixed-build
1978endif # need-sub-make
1979
1980PHONY += FORCE
1981FORCE:
1982
1983# Declare the contents of the PHONY variable as phony.  We keep that
1984# information in a variable so we can use it in if_changed and friends.
1985.PHONY: $(PHONY)
1986