xref: /openbmc/linux/Makefile (revision 5c816641)
1# SPDX-License-Identifier: GPL-2.0
2VERSION = 5
3PATCHLEVEL = 17
4SUBLEVEL = 0
5EXTRAVERSION = -rc4
6NAME = Superb Owl
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	$(error building multiple external modules is not supported))
131
132# Remove trailing slashes
133ifneq ($(filter %/, $(KBUILD_EXTMOD)),)
134KBUILD_EXTMOD := $(shell dirname $(KBUILD_EXTMOD).)
135endif
136
137export KBUILD_EXTMOD
138
139# Kbuild will save output files in the current working directory.
140# This does not need to match to the root of the kernel source tree.
141#
142# For example, you can do this:
143#
144#  cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
145#
146# If you want to save output files in a different location, there are
147# two syntaxes to specify it.
148#
149# 1) O=
150# Use "make O=dir/to/store/output/files/"
151#
152# 2) Set KBUILD_OUTPUT
153# Set the environment variable KBUILD_OUTPUT to point to the output directory.
154# export KBUILD_OUTPUT=dir/to/store/output/files/; make
155#
156# The O= assignment takes precedence over the KBUILD_OUTPUT environment
157# variable.
158
159# Do we want to change the working directory?
160ifeq ("$(origin O)", "command line")
161  KBUILD_OUTPUT := $(O)
162endif
163
164ifneq ($(KBUILD_OUTPUT),)
165# Make's built-in functions such as $(abspath ...), $(realpath ...) cannot
166# expand a shell special character '~'. We use a somewhat tedious way here.
167abs_objtree := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) && pwd)
168$(if $(abs_objtree),, \
169     $(error failed to create output directory "$(KBUILD_OUTPUT)"))
170
171# $(realpath ...) resolves symlinks
172abs_objtree := $(realpath $(abs_objtree))
173else
174abs_objtree := $(CURDIR)
175endif # ifneq ($(KBUILD_OUTPUT),)
176
177ifeq ($(abs_objtree),$(CURDIR))
178# Suppress "Entering directory ..." unless we are changing the work directory.
179MAKEFLAGS += --no-print-directory
180else
181need-sub-make := 1
182endif
183
184this-makefile := $(lastword $(MAKEFILE_LIST))
185abs_srctree := $(realpath $(dir $(this-makefile)))
186
187ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
188$(error source directory cannot contain spaces or colons)
189endif
190
191ifneq ($(abs_srctree),$(abs_objtree))
192# Look for make include files relative to root of kernel src
193#
194# --included-dir is added for backward compatibility, but you should not rely on
195# it. Please add $(srctree)/ prefix to include Makefiles in the source tree.
196MAKEFLAGS += --include-dir=$(abs_srctree)
197endif
198
199ifneq ($(filter 3.%,$(MAKE_VERSION)),)
200# 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
201# We need to invoke sub-make to avoid implicit rules in the top Makefile.
202need-sub-make := 1
203# Cancel implicit rules for this Makefile.
204$(this-makefile): ;
205endif
206
207export abs_srctree abs_objtree
208export sub_make_done := 1
209
210ifeq ($(need-sub-make),1)
211
212PHONY += $(MAKECMDGOALS) __sub-make
213
214$(filter-out $(this-makefile), $(MAKECMDGOALS)) __all: __sub-make
215	@:
216
217# Invoke a second make in the output directory, passing relevant variables
218__sub-make:
219	$(Q)$(MAKE) -C $(abs_objtree) -f $(abs_srctree)/Makefile $(MAKECMDGOALS)
220
221endif # need-sub-make
222endif # sub_make_done
223
224# We process the rest of the Makefile if this is the final invocation of make
225ifeq ($(need-sub-make),)
226
227# Do not print "Entering directory ...",
228# but we want to display it when entering to the output directory
229# so that IDEs/editors are able to understand relative filenames.
230MAKEFLAGS += --no-print-directory
231
232ifeq ($(abs_srctree),$(abs_objtree))
233        # building in the source tree
234        srctree := .
235	building_out_of_srctree :=
236else
237        ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
238                # building in a subdirectory of the source tree
239                srctree := ..
240        else
241                srctree := $(abs_srctree)
242        endif
243	building_out_of_srctree := 1
244endif
245
246ifneq ($(KBUILD_ABS_SRCTREE),)
247srctree := $(abs_srctree)
248endif
249
250objtree		:= .
251VPATH		:= $(srctree)
252
253export building_out_of_srctree srctree objtree VPATH
254
255# To make sure we do not include .config for any of the *config targets
256# catch them early, and hand them over to scripts/kconfig/Makefile
257# It is allowed to specify more targets when calling make, including
258# mixing *config targets and build targets.
259# For example 'make oldconfig all'.
260# Detect when mixed targets is specified, and make a second invocation
261# of make so .config is not included in this case either (for *config).
262
263version_h := include/generated/uapi/linux/version.h
264
265clean-targets := %clean mrproper cleandocs
266no-dot-config-targets := $(clean-targets) \
267			 cscope gtags TAGS tags help% %docs check% coccicheck \
268			 $(version_h) headers headers_% archheaders archscripts \
269			 %asm-generic kernelversion %src-pkg dt_binding_check \
270			 outputmakefile
271# Installation targets should not require compiler. Unfortunately, vdso_install
272# is an exception where build artifacts may be updated. This must be fixed.
273no-compiler-targets := $(no-dot-config-targets) install dtbs_install \
274			headers_install modules_install kernelrelease image_name
275no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease \
276			  image_name
277single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
278
279config-build	:=
280mixed-build	:=
281need-config	:= 1
282need-compiler	:= 1
283may-sync-config	:= 1
284single-build	:=
285
286ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
287	ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
288		need-config :=
289	endif
290endif
291
292ifneq ($(filter $(no-compiler-targets), $(MAKECMDGOALS)),)
293	ifeq ($(filter-out $(no-compiler-targets), $(MAKECMDGOALS)),)
294		need-compiler :=
295	endif
296endif
297
298ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
299	ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
300		may-sync-config :=
301	endif
302endif
303
304ifneq ($(KBUILD_EXTMOD),)
305	may-sync-config :=
306endif
307
308ifeq ($(KBUILD_EXTMOD),)
309        ifneq ($(filter %config,$(MAKECMDGOALS)),)
310		config-build := 1
311                ifneq ($(words $(MAKECMDGOALS)),1)
312			mixed-build := 1
313                endif
314        endif
315endif
316
317# We cannot build single targets and the others at the same time
318ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
319	single-build := 1
320	ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
321		mixed-build := 1
322	endif
323endif
324
325# For "make -j clean all", "make -j mrproper defconfig all", etc.
326ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
327        ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
328		mixed-build := 1
329        endif
330endif
331
332# install and modules_install need also be processed one by one
333ifneq ($(filter install,$(MAKECMDGOALS)),)
334        ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
335		mixed-build := 1
336        endif
337endif
338
339ifdef mixed-build
340# ===========================================================================
341# We're called with mixed targets (*config and build targets).
342# Handle them one by one.
343
344PHONY += $(MAKECMDGOALS) __build_one_by_one
345
346$(MAKECMDGOALS): __build_one_by_one
347	@:
348
349__build_one_by_one:
350	$(Q)set -e; \
351	for i in $(MAKECMDGOALS); do \
352		$(MAKE) -f $(srctree)/Makefile $$i; \
353	done
354
355else # !mixed-build
356
357include $(srctree)/scripts/Kbuild.include
358
359# Read KERNELRELEASE from include/config/kernel.release (if it exists)
360KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
361KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
362export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
363
364include $(srctree)/scripts/subarch.include
365
366# Cross compiling and selecting different set of gcc/bin-utils
367# ---------------------------------------------------------------------------
368#
369# When performing cross compilation for other architectures ARCH shall be set
370# to the target architecture. (See arch/* for the possibilities).
371# ARCH can be set during invocation of make:
372# make ARCH=ia64
373# Another way is to have ARCH set in the environment.
374# The default ARCH is the host where make is executed.
375
376# CROSS_COMPILE specify the prefix used for all executables used
377# during compilation. Only gcc and related bin-utils executables
378# are prefixed with $(CROSS_COMPILE).
379# CROSS_COMPILE can be set on the command line
380# make CROSS_COMPILE=ia64-linux-
381# Alternatively CROSS_COMPILE can be set in the environment.
382# Default value for CROSS_COMPILE is not to prefix executables
383# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
384ARCH		?= $(SUBARCH)
385
386# Architecture as present in compile.h
387UTS_MACHINE 	:= $(ARCH)
388SRCARCH 	:= $(ARCH)
389
390# Additional ARCH settings for x86
391ifeq ($(ARCH),i386)
392        SRCARCH := x86
393endif
394ifeq ($(ARCH),x86_64)
395        SRCARCH := x86
396endif
397
398# Additional ARCH settings for sparc
399ifeq ($(ARCH),sparc32)
400       SRCARCH := sparc
401endif
402ifeq ($(ARCH),sparc64)
403       SRCARCH := sparc
404endif
405
406# Additional ARCH settings for parisc
407ifeq ($(ARCH),parisc64)
408       SRCARCH := parisc
409endif
410
411export cross_compiling :=
412ifneq ($(SRCARCH),$(SUBARCH))
413cross_compiling := 1
414endif
415
416KCONFIG_CONFIG	?= .config
417export KCONFIG_CONFIG
418
419# SHELL used by kbuild
420CONFIG_SHELL := sh
421
422HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
423HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
424HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
425
426ifneq ($(LLVM),)
427HOSTCC	= clang
428HOSTCXX	= clang++
429else
430HOSTCC	= gcc
431HOSTCXX	= g++
432endif
433
434KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
435			 -O2 -fomit-frame-pointer -std=gnu89
436KBUILD_USERCFLAGS  := $(KBUILD_USERHOSTCFLAGS) $(USERCFLAGS)
437KBUILD_USERLDFLAGS := $(USERLDFLAGS)
438
439KBUILD_HOSTCFLAGS   := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
440KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
441KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
442KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
443
444# Make variables (CC, etc...)
445CPP		= $(CC) -E
446ifneq ($(LLVM),)
447CC		= clang
448LD		= ld.lld
449AR		= llvm-ar
450NM		= llvm-nm
451OBJCOPY		= llvm-objcopy
452OBJDUMP		= llvm-objdump
453READELF		= llvm-readelf
454STRIP		= llvm-strip
455else
456CC		= $(CROSS_COMPILE)gcc
457LD		= $(CROSS_COMPILE)ld
458AR		= $(CROSS_COMPILE)ar
459NM		= $(CROSS_COMPILE)nm
460OBJCOPY		= $(CROSS_COMPILE)objcopy
461OBJDUMP		= $(CROSS_COMPILE)objdump
462READELF		= $(CROSS_COMPILE)readelf
463STRIP		= $(CROSS_COMPILE)strip
464endif
465PAHOLE		= pahole
466RESOLVE_BTFIDS	= $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
467LEX		= flex
468YACC		= bison
469AWK		= awk
470INSTALLKERNEL  := installkernel
471DEPMOD		= depmod
472PERL		= perl
473PYTHON3		= python3
474CHECK		= sparse
475BASH		= bash
476KGZIP		= gzip
477KBZIP2		= bzip2
478KLZOP		= lzop
479LZMA		= lzma
480LZ4		= lz4c
481XZ		= xz
482ZSTD		= zstd
483
484PAHOLE_FLAGS	= $(shell PAHOLE=$(PAHOLE) $(srctree)/scripts/pahole-flags.sh)
485
486CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
487		  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
488NOSTDINC_FLAGS :=
489CFLAGS_MODULE   =
490AFLAGS_MODULE   =
491LDFLAGS_MODULE  =
492CFLAGS_KERNEL	=
493AFLAGS_KERNEL	=
494LDFLAGS_vmlinux =
495
496# Use USERINCLUDE when you must reference the UAPI directories only.
497USERINCLUDE    := \
498		-I$(srctree)/arch/$(SRCARCH)/include/uapi \
499		-I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
500		-I$(srctree)/include/uapi \
501		-I$(objtree)/include/generated/uapi \
502                -include $(srctree)/include/linux/compiler-version.h \
503                -include $(srctree)/include/linux/kconfig.h
504
505# Use LINUXINCLUDE when you must reference the include/ directory.
506# Needed to be compatible with the O= option
507LINUXINCLUDE    := \
508		-I$(srctree)/arch/$(SRCARCH)/include \
509		-I$(objtree)/arch/$(SRCARCH)/include/generated \
510		$(if $(building_out_of_srctree),-I$(srctree)/include) \
511		-I$(objtree)/include \
512		$(USERINCLUDE)
513
514KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
515KBUILD_CFLAGS   := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
516		   -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
517		   -Werror=implicit-function-declaration -Werror=implicit-int \
518		   -Werror=return-type -Wno-format-security \
519		   -std=gnu89
520KBUILD_CPPFLAGS := -D__KERNEL__
521KBUILD_AFLAGS_KERNEL :=
522KBUILD_CFLAGS_KERNEL :=
523KBUILD_AFLAGS_MODULE  := -DMODULE
524KBUILD_CFLAGS_MODULE  := -DMODULE
525KBUILD_LDFLAGS_MODULE :=
526KBUILD_LDFLAGS :=
527CLANG_FLAGS :=
528
529export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC
530export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
531export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
532export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
533export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
534export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS
535
536export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
537export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
538export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
539export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
540export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
541export PAHOLE_FLAGS
542
543# Files to ignore in find ... statements
544
545export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
546			  -name CVS -o -name .pc -o -name .hg -o -name .git \) \
547			  -prune -o
548export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
549			 --exclude CVS --exclude .pc --exclude .hg --exclude .git
550
551# ===========================================================================
552# Rules shared between *config targets and build targets
553
554# Basic helpers built in scripts/basic/
555PHONY += scripts_basic
556scripts_basic:
557	$(Q)$(MAKE) $(build)=scripts/basic
558
559PHONY += outputmakefile
560ifdef building_out_of_srctree
561# Before starting out-of-tree build, make sure the source tree is clean.
562# outputmakefile generates a Makefile in the output directory, if using a
563# separate output directory. This allows convenient use of make in the
564# output directory.
565# At the same time when output Makefile generated, generate .gitignore to
566# ignore whole output directory
567
568quiet_cmd_makefile = GEN     Makefile
569      cmd_makefile = { \
570	echo "\# Automatically generated by $(srctree)/Makefile: don't edit"; \
571	echo "include $(srctree)/Makefile"; \
572	} > Makefile
573
574outputmakefile:
575	$(Q)if [ -f $(srctree)/.config -o \
576		 -d $(srctree)/include/config -o \
577		 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
578		echo >&2 "***"; \
579		echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
580		echo >&2 "*** in $(abs_srctree)";\
581		echo >&2 "***"; \
582		false; \
583	fi
584	$(Q)ln -fsn $(srctree) source
585	$(call cmd,makefile)
586	$(Q)test -e .gitignore || \
587	{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
588endif
589
590# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
591# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
592# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
593# and from include/config/auto.conf.cmd to detect the compiler upgrade.
594CC_VERSION_TEXT = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1))
595
596ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
597include $(srctree)/scripts/Makefile.clang
598endif
599
600# Include this also for config targets because some architectures need
601# cc-cross-prefix to determine CROSS_COMPILE.
602ifdef need-compiler
603include $(srctree)/scripts/Makefile.compiler
604endif
605
606ifdef config-build
607# ===========================================================================
608# *config targets only - make sure prerequisites are updated, and descend
609# in scripts/kconfig to make the *config target
610
611# Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
612# KBUILD_DEFCONFIG may point out an alternative default configuration
613# used for 'make defconfig'
614include $(srctree)/arch/$(SRCARCH)/Makefile
615export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
616
617config: outputmakefile scripts_basic FORCE
618	$(Q)$(MAKE) $(build)=scripts/kconfig $@
619
620%config: outputmakefile scripts_basic FORCE
621	$(Q)$(MAKE) $(build)=scripts/kconfig $@
622
623else #!config-build
624# ===========================================================================
625# Build targets only - this includes vmlinux, arch specific targets, clean
626# targets and others. In general all targets except *config targets.
627
628# If building an external module we do not care about the all: rule
629# but instead __all depend on modules
630PHONY += all
631ifeq ($(KBUILD_EXTMOD),)
632__all: all
633else
634__all: modules
635endif
636
637# Decide whether to build built-in, modular, or both.
638# Normally, just do built-in.
639
640KBUILD_MODULES :=
641KBUILD_BUILTIN := 1
642
643# If we have only "make modules", don't compile built-in objects.
644ifeq ($(MAKECMDGOALS),modules)
645  KBUILD_BUILTIN :=
646endif
647
648# If we have "make <whatever> modules", compile modules
649# in addition to whatever we do anyway.
650# Just "make" or "make all" shall build modules as well
651
652ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
653  KBUILD_MODULES := 1
654endif
655
656ifeq ($(MAKECMDGOALS),)
657  KBUILD_MODULES := 1
658endif
659
660export KBUILD_MODULES KBUILD_BUILTIN
661
662ifdef need-config
663include include/config/auto.conf
664endif
665
666ifeq ($(KBUILD_EXTMOD),)
667# Objects we will link into vmlinux / subdirs we need to visit
668core-y		:= init/ usr/ arch/$(SRCARCH)/
669drivers-y	:= drivers/ sound/
670drivers-$(CONFIG_SAMPLES) += samples/
671drivers-$(CONFIG_NET) += net/
672drivers-y	+= virt/
673libs-y		:= lib/
674endif # KBUILD_EXTMOD
675
676# The all: target is the default when no target is given on the
677# command line.
678# This allow a user to issue only 'make' to build a kernel including modules
679# Defaults to vmlinux, but the arch makefile usually adds further targets
680all: vmlinux
681
682CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage
683ifdef CONFIG_CC_IS_GCC
684CFLAGS_GCOV	+= -fno-tree-loop-im
685endif
686export CFLAGS_GCOV
687
688# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
689ifdef CONFIG_FUNCTION_TRACER
690  CC_FLAGS_FTRACE := -pg
691endif
692
693include $(srctree)/arch/$(SRCARCH)/Makefile
694
695ifdef need-config
696ifdef may-sync-config
697# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
698# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
699# because some architectures define CROSS_COMPILE there.
700include include/config/auto.conf.cmd
701
702$(KCONFIG_CONFIG):
703	@echo >&2 '***'
704	@echo >&2 '*** Configuration file "$@" not found!'
705	@echo >&2 '***'
706	@echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
707	@echo >&2 '*** "make menuconfig" or "make xconfig").'
708	@echo >&2 '***'
709	@/bin/false
710
711# The actual configuration files used during the build are stored in
712# include/generated/ and include/config/. Update them if .config is newer than
713# include/config/auto.conf (which mirrors .config).
714#
715# This exploits the 'multi-target pattern rule' trick.
716# The syncconfig should be executed only once to make all the targets.
717# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
718#
719# Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
720# so you cannot notice that Kconfig is waiting for the user input.
721%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h: $(KCONFIG_CONFIG)
722	$(Q)$(kecho) "  SYNC    $@"
723	$(Q)$(MAKE) -f $(srctree)/Makefile 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	+= -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
757ifdef CONFIG_CC_IS_GCC
758# gcc-10 renamed --param=allow-store-data-races=0 to
759# -fno-allow-store-data-races.
760KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
761KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
762endif
763
764ifdef CONFIG_READABLE_ASM
765# Disable optimizations that make assembler listings hard to read.
766# reorder blocks reorders the control in the function
767# ipa clone creates specialized cloned functions
768# partial inlining inlines only parts of functions
769KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
770endif
771
772ifneq ($(CONFIG_FRAME_WARN),0)
773KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
774endif
775
776stackp-flags-y                                    := -fno-stack-protector
777stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
778stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
779
780KBUILD_CFLAGS += $(stackp-flags-y)
781
782KBUILD_CFLAGS-$(CONFIG_WERROR) += -Werror
783KBUILD_CFLAGS += $(KBUILD_CFLAGS-y) $(CONFIG_CC_IMPLICIT_FALLTHROUGH)
784
785ifdef CONFIG_CC_IS_CLANG
786KBUILD_CPPFLAGS += -Qunused-arguments
787# The kernel builds with '-std=gnu89' so use of GNU extensions is acceptable.
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# gcc inanely warns about local variables called 'main'
796KBUILD_CFLAGS += -Wno-main
797endif
798
799# These warnings generated too much noise in a regular build.
800# Use make W=1 to enable them (see scripts/Makefile.extrawarn)
801KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
802KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
803
804ifdef CONFIG_FRAME_POINTER
805KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
806else
807# Some targets (ARM with Thumb2, for example), can't be built with frame
808# pointers.  For those, we don't have FUNCTION_TRACER automatically
809# select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
810# incompatible with -fomit-frame-pointer with current GCC, so we don't use
811# -fomit-frame-pointer with FUNCTION_TRACER.
812ifndef CONFIG_FUNCTION_TRACER
813KBUILD_CFLAGS	+= -fomit-frame-pointer
814endif
815endif
816
817# Initialize all stack variables with a 0xAA pattern.
818ifdef CONFIG_INIT_STACK_ALL_PATTERN
819KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
820endif
821
822# Initialize all stack variables with a zero value.
823ifdef CONFIG_INIT_STACK_ALL_ZERO
824KBUILD_CFLAGS	+= -ftrivial-auto-var-init=zero
825ifdef CONFIG_CC_IS_CLANG
826# https://bugs.llvm.org/show_bug.cgi?id=45497
827KBUILD_CFLAGS	+= -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
828endif
829endif
830
831# While VLAs have been removed, GCC produces unreachable stack probes
832# for the randomize_kstack_offset feature. Disable it for all compilers.
833KBUILD_CFLAGS	+= $(call cc-option, -fno-stack-clash-protection)
834
835# Clear used registers at func exit (to reduce data lifetime and ROP gadgets).
836ifdef CONFIG_ZERO_CALL_USED_REGS
837KBUILD_CFLAGS	+= -fzero-call-used-regs=used-gpr
838endif
839
840ifdef CONFIG_FUNCTION_TRACER
841ifdef CONFIG_FTRACE_MCOUNT_USE_CC
842  CC_FLAGS_FTRACE	+= -mrecord-mcount
843  ifdef CONFIG_HAVE_NOP_MCOUNT
844    ifeq ($(call cc-option-yn, -mnop-mcount),y)
845      CC_FLAGS_FTRACE	+= -mnop-mcount
846      CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
847    endif
848  endif
849endif
850ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
851  CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
852endif
853ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
854  ifdef CONFIG_HAVE_C_RECORDMCOUNT
855    BUILD_C_RECORDMCOUNT := y
856    export BUILD_C_RECORDMCOUNT
857  endif
858endif
859ifdef CONFIG_HAVE_FENTRY
860  # s390-linux-gnu-gcc did not support -mfentry until gcc-9.
861  ifeq ($(call cc-option-yn, -mfentry),y)
862    CC_FLAGS_FTRACE	+= -mfentry
863    CC_FLAGS_USING	+= -DCC_USING_FENTRY
864  endif
865endif
866export CC_FLAGS_FTRACE
867KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
868KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
869endif
870
871# We trigger additional mismatches with less inlining
872ifdef CONFIG_DEBUG_SECTION_MISMATCH
873KBUILD_CFLAGS += -fno-inline-functions-called-once
874endif
875
876ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
877KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
878LDFLAGS_vmlinux += --gc-sections
879endif
880
881ifdef CONFIG_SHADOW_CALL_STACK
882CC_FLAGS_SCS	:= -fsanitize=shadow-call-stack
883KBUILD_CFLAGS	+= $(CC_FLAGS_SCS)
884export CC_FLAGS_SCS
885endif
886
887ifdef CONFIG_LTO_CLANG
888ifdef CONFIG_LTO_CLANG_THIN
889CC_FLAGS_LTO	:= -flto=thin -fsplit-lto-unit
890KBUILD_LDFLAGS	+= --thinlto-cache-dir=$(extmod_prefix).thinlto-cache
891else
892CC_FLAGS_LTO	:= -flto
893endif
894CC_FLAGS_LTO	+= -fvisibility=hidden
895
896# Limit inlining across translation units to reduce binary size
897KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
898
899# Check for frame size exceeding threshold during prolog/epilog insertion
900# when using lld < 13.0.0.
901ifneq ($(CONFIG_FRAME_WARN),0)
902ifeq ($(shell test $(CONFIG_LLD_VERSION) -lt 130000; echo $$?),0)
903KBUILD_LDFLAGS	+= -plugin-opt=-warn-stack-size=$(CONFIG_FRAME_WARN)
904endif
905endif
906endif
907
908ifdef CONFIG_LTO
909KBUILD_CFLAGS	+= -fno-lto $(CC_FLAGS_LTO)
910KBUILD_AFLAGS	+= -fno-lto
911export CC_FLAGS_LTO
912endif
913
914ifdef CONFIG_CFI_CLANG
915CC_FLAGS_CFI	:= -fsanitize=cfi \
916		   -fsanitize-cfi-cross-dso \
917		   -fno-sanitize-cfi-canonical-jump-tables \
918		   -fno-sanitize-trap=cfi \
919		   -fno-sanitize-blacklist
920
921ifdef CONFIG_CFI_PERMISSIVE
922CC_FLAGS_CFI	+= -fsanitize-recover=cfi
923endif
924
925# If LTO flags are filtered out, we must also filter out CFI.
926CC_FLAGS_LTO	+= $(CC_FLAGS_CFI)
927KBUILD_CFLAGS	+= $(CC_FLAGS_CFI)
928export CC_FLAGS_CFI
929endif
930
931ifdef CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_64B
932KBUILD_CFLAGS += -falign-functions=64
933endif
934
935# arch Makefile may override CC so keep this after arch Makefile is included
936NOSTDINC_FLAGS += -nostdinc
937
938# warn about C99 declaration after statement
939KBUILD_CFLAGS += -Wdeclaration-after-statement
940
941# Variable Length Arrays (VLAs) should not be used anywhere in the kernel
942KBUILD_CFLAGS += -Wvla
943
944# disable pointer signed / unsigned warnings in gcc 4.0
945KBUILD_CFLAGS += -Wno-pointer-sign
946
947# In order to make sure new function cast mismatches are not introduced
948# in the kernel (to avoid tripping CFI checking), the kernel should be
949# globally built with -Wcast-function-type.
950KBUILD_CFLAGS += $(call cc-option, -Wcast-function-type)
951
952# disable stringop warnings in gcc 8+
953KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
954
955# We'll want to enable this eventually, but it's not going away for 5.7 at least
956KBUILD_CFLAGS += $(call cc-disable-warning, zero-length-bounds)
957KBUILD_CFLAGS += -Wno-array-bounds
958KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
959
960# Another good warning that we'll want to enable eventually
961KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
962
963# Enabled with W=2, disabled by default as noisy
964ifdef CONFIG_CC_IS_GCC
965KBUILD_CFLAGS += -Wno-maybe-uninitialized
966endif
967
968ifdef CONFIG_CC_IS_GCC
969# The allocators already balk at large sizes, so silence the compiler
970# warnings for bounds checks involving those possible values. While
971# -Wno-alloc-size-larger-than would normally be used here, earlier versions
972# of gcc (<9.1) weirdly don't handle the option correctly when _other_
973# warnings are produced (?!). Using -Walloc-size-larger-than=SIZE_MAX
974# doesn't work (as it is documented to), silently resolving to "0" prior to
975# version 9.1 (and producing an error more recently). Numeric values larger
976# than PTRDIFF_MAX also don't work prior to version 9.1, which are silently
977# ignored, continuing to default to PTRDIFF_MAX. So, left with no other
978# choice, we must perform a versioned check to disable this warning.
979# https://lore.kernel.org/lkml/20210824115859.187f272f@canb.auug.org.au
980KBUILD_CFLAGS += $(call cc-ifversion, -ge, 0901, -Wno-alloc-size-larger-than)
981endif
982
983# disable invalid "can't wrap" optimizations for signed / pointers
984KBUILD_CFLAGS	+= -fno-strict-overflow
985
986# Make sure -fstack-check isn't enabled (like gentoo apparently did)
987KBUILD_CFLAGS  += -fno-stack-check
988
989# conserve stack if available
990ifdef CONFIG_CC_IS_GCC
991KBUILD_CFLAGS   += -fconserve-stack
992endif
993
994# Prohibit date/time macros, which would make the build non-deterministic
995KBUILD_CFLAGS   += -Werror=date-time
996
997# enforce correct pointer usage
998KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)
999
1000# Require designated initializers for all marked structures
1001KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)
1002
1003# change __FILE__ to the relative path from the srctree
1004KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
1005
1006# include additional Makefiles when needed
1007include-y			:= scripts/Makefile.extrawarn
1008include-$(CONFIG_DEBUG_INFO)	+= scripts/Makefile.debug
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 --use-android-relr-tags
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
1084PHONY += prepare0
1085
1086export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
1087export MODORDER := $(extmod_prefix)modules.order
1088export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
1089
1090ifeq ($(KBUILD_EXTMOD),)
1091core-y			+= kernel/ certs/ mm/ fs/ ipc/ security/ crypto/
1092core-$(CONFIG_BLOCK)	+= block/
1093
1094vmlinux-dirs	:= $(patsubst %/,%,$(filter %/, \
1095		     $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
1096		     $(libs-y) $(libs-m)))
1097
1098vmlinux-alldirs	:= $(sort $(vmlinux-dirs) Documentation \
1099		     $(patsubst %/,%,$(filter %/, $(core-) \
1100			$(drivers-) $(libs-))))
1101
1102subdir-modorder := $(addsuffix modules.order,$(filter %/, \
1103			$(core-y) $(core-m) $(libs-y) $(libs-m) \
1104			$(drivers-y) $(drivers-m)))
1105
1106build-dirs	:= $(vmlinux-dirs)
1107clean-dirs	:= $(vmlinux-alldirs)
1108
1109# Externally visible symbols (used by link-vmlinux.sh)
1110KBUILD_VMLINUX_OBJS := $(head-y) $(patsubst %/,%/built-in.a, $(core-y))
1111KBUILD_VMLINUX_OBJS += $(addsuffix built-in.a, $(filter %/, $(libs-y)))
1112ifdef CONFIG_MODULES
1113KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1114KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1115else
1116KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1117endif
1118KBUILD_VMLINUX_OBJS += $(patsubst %/,%/built-in.a, $(drivers-y))
1119
1120export KBUILD_VMLINUX_OBJS KBUILD_VMLINUX_LIBS
1121export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1122# used by scripts/Makefile.package
1123export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) LICENSES arch include scripts tools)
1124
1125vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
1126
1127# Recurse until adjust_autoksyms.sh is satisfied
1128PHONY += autoksyms_recursive
1129ifdef CONFIG_TRIM_UNUSED_KSYMS
1130# For the kernel to actually contain only the needed exported symbols,
1131# we have to build modules as well to determine what those symbols are.
1132# (this can be evaluated only once include/config/auto.conf has been included)
1133KBUILD_MODULES := 1
1134
1135autoksyms_recursive: descend modules.order
1136	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1137	  "$(MAKE) -f $(srctree)/Makefile vmlinux"
1138endif
1139
1140autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1141
1142quiet_cmd_autoksyms_h = GEN     $@
1143      cmd_autoksyms_h = mkdir -p $(dir $@); \
1144			$(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@
1145
1146$(autoksyms_h):
1147	$(call cmd,autoksyms_h)
1148
1149ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1150
1151# Final link of vmlinux with optional arch pass after final link
1152cmd_link-vmlinux =                                                 \
1153	$(CONFIG_SHELL) $< "$(LD)" "$(KBUILD_LDFLAGS)" "$(LDFLAGS_vmlinux)";    \
1154	$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1155
1156vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1157	+$(call if_changed_dep,link-vmlinux)
1158
1159targets := vmlinux
1160
1161# The actual objects are generated when descending,
1162# make sure no implicit rule kicks in
1163$(sort $(vmlinux-deps) $(subdir-modorder)): descend ;
1164
1165filechk_kernel.release = \
1166	echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1167
1168# Store (new) KERNELRELEASE string in include/config/kernel.release
1169include/config/kernel.release: FORCE
1170	$(call filechk,kernel.release)
1171
1172# Additional helpers built in scripts/
1173# Carefully list dependencies so we do not try to build scripts twice
1174# in parallel
1175PHONY += scripts
1176scripts: scripts_basic scripts_dtc
1177	$(Q)$(MAKE) $(build)=$(@)
1178
1179# Things we need to do before we recursively start building the kernel
1180# or the modules are listed in "prepare".
1181# A multi level approach is used. prepareN is processed before prepareN-1.
1182# archprepare is used in arch Makefiles and when processed asm symlink,
1183# version.h and scripts_basic is processed / created.
1184
1185PHONY += prepare archprepare
1186
1187archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1188	asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h \
1189	include/generated/autoconf.h remove-stale-files
1190
1191prepare0: archprepare
1192	$(Q)$(MAKE) $(build)=scripts/mod
1193	$(Q)$(MAKE) $(build)=.
1194
1195# All the preparing..
1196prepare: prepare0
1197
1198PHONY += remove-stale-files
1199remove-stale-files:
1200	$(Q)$(srctree)/scripts/remove-stale-files
1201
1202# Support for using generic headers in asm-generic
1203asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1204
1205PHONY += asm-generic uapi-asm-generic
1206asm-generic: uapi-asm-generic
1207	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1208	generic=include/asm-generic
1209uapi-asm-generic:
1210	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1211	generic=include/uapi/asm-generic
1212
1213# Generate some files
1214# ---------------------------------------------------------------------------
1215
1216# KERNELRELEASE can change from a few different places, meaning version.h
1217# needs to be updated, so this check is forced on all builds
1218
1219uts_len := 64
1220define filechk_utsrelease.h
1221	if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1222	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1223	  exit 1;                                                         \
1224	fi;                                                               \
1225	echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1226endef
1227
1228define filechk_version.h
1229	if [ $(SUBLEVEL) -gt 255 ]; then                                 \
1230		echo \#define LINUX_VERSION_CODE $(shell                 \
1231		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1232	else                                                             \
1233		echo \#define LINUX_VERSION_CODE $(shell                 \
1234		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1235	fi;                                                              \
1236	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
1237	((c) > 255 ? 255 : (c)))';                                       \
1238	echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
1239	echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
1240	echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1241endef
1242
1243$(version_h): PATCHLEVEL := $(or $(PATCHLEVEL), 0)
1244$(version_h): SUBLEVEL := $(or $(SUBLEVEL), 0)
1245$(version_h): FORCE
1246	$(call filechk,version.h)
1247
1248include/generated/utsrelease.h: include/config/kernel.release FORCE
1249	$(call filechk,utsrelease.h)
1250
1251PHONY += headerdep
1252headerdep:
1253	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1254	$(srctree)/scripts/headerdep.pl -I$(srctree)/include
1255
1256# ---------------------------------------------------------------------------
1257# Kernel headers
1258
1259#Default location for installed headers
1260export INSTALL_HDR_PATH = $(objtree)/usr
1261
1262quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1263      cmd_headers_install = \
1264	mkdir -p $(INSTALL_HDR_PATH); \
1265	rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1266	usr/include $(INSTALL_HDR_PATH)
1267
1268PHONY += headers_install
1269headers_install: headers
1270	$(call cmd,headers_install)
1271
1272PHONY += archheaders archscripts
1273
1274hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1275
1276PHONY += headers
1277headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1278	$(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1279	  $(error Headers not exportable for the $(SRCARCH) architecture))
1280	$(Q)$(MAKE) $(hdr-inst)=include/uapi
1281	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1282
1283ifdef CONFIG_HEADERS_INSTALL
1284prepare: headers
1285endif
1286
1287PHONY += scripts_unifdef
1288scripts_unifdef: scripts_basic
1289	$(Q)$(MAKE) $(build)=scripts scripts/unifdef
1290
1291# ---------------------------------------------------------------------------
1292# Install
1293
1294# Many distributions have the custom install script, /sbin/installkernel.
1295# If DKMS is installed, 'make install' will eventually recuses back
1296# to the this Makefile to build and install external modules.
1297# Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
1298
1299install: sub_make_done :=
1300
1301# ---------------------------------------------------------------------------
1302# Tools
1303
1304ifdef CONFIG_STACK_VALIDATION
1305prepare: tools/objtool
1306endif
1307
1308ifdef CONFIG_BPF
1309ifdef CONFIG_DEBUG_INFO_BTF
1310prepare: tools/bpf/resolve_btfids
1311endif
1312endif
1313
1314PHONY += resolve_btfids_clean
1315
1316resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1317
1318# tools/bpf/resolve_btfids directory might not exist
1319# in output directory, skip its clean in that case
1320resolve_btfids_clean:
1321ifneq ($(wildcard $(resolve_btfids_O)),)
1322	$(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1323endif
1324
1325# Clear a bunch of variables before executing the submake
1326ifeq ($(quiet),silent_)
1327tools_silent=s
1328endif
1329
1330tools/: FORCE
1331	$(Q)mkdir -p $(objtree)/tools
1332	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1333
1334tools/%: FORCE
1335	$(Q)mkdir -p $(objtree)/tools
1336	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1337
1338# ---------------------------------------------------------------------------
1339# Kernel selftest
1340
1341PHONY += kselftest
1342kselftest:
1343	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1344
1345kselftest-%: FORCE
1346	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1347
1348PHONY += kselftest-merge
1349kselftest-merge:
1350	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1351	$(Q)find $(srctree)/tools/testing/selftests -name config | \
1352		xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1353	$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1354
1355# ---------------------------------------------------------------------------
1356# Devicetree files
1357
1358ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1359dtstree := arch/$(SRCARCH)/boot/dts
1360endif
1361
1362ifneq ($(dtstree),)
1363
1364%.dtb: include/config/kernel.release scripts_dtc
1365	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1366
1367%.dtbo: include/config/kernel.release scripts_dtc
1368	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1369
1370PHONY += dtbs dtbs_install dtbs_check
1371dtbs: include/config/kernel.release scripts_dtc
1372	$(Q)$(MAKE) $(build)=$(dtstree)
1373
1374ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1375export CHECK_DTBS=y
1376dtbs: dt_binding_check
1377endif
1378
1379dtbs_check: dtbs
1380
1381dtbs_install:
1382	$(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1383
1384ifdef CONFIG_OF_EARLY_FLATTREE
1385all: dtbs
1386endif
1387
1388endif
1389
1390PHONY += scripts_dtc
1391scripts_dtc: scripts_basic
1392	$(Q)$(MAKE) $(build)=scripts/dtc
1393
1394ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1395export CHECK_DT_BINDING=y
1396endif
1397
1398PHONY += dt_binding_check
1399dt_binding_check: scripts_dtc
1400	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1401
1402# ---------------------------------------------------------------------------
1403# Modules
1404
1405ifdef CONFIG_MODULES
1406
1407# By default, build modules as well
1408
1409all: modules
1410
1411# When we're building modules with modversions, we need to consider
1412# the built-in objects during the descend as well, in order to
1413# make sure the checksums are up to date before we record them.
1414ifdef CONFIG_MODVERSIONS
1415  KBUILD_BUILTIN := 1
1416endif
1417
1418# Build modules
1419#
1420# A module can be listed more than once in obj-m resulting in
1421# duplicate lines in modules.order files.  Those are removed
1422# using awk while concatenating to the final file.
1423
1424PHONY += modules
1425modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_check modules_prepare
1426
1427cmd_modules_order = $(AWK) '!x[$$0]++' $(real-prereqs) > $@
1428
1429modules.order: $(subdir-modorder) FORCE
1430	$(call if_changed,modules_order)
1431
1432targets += modules.order
1433
1434# Target to prepare building external modules
1435PHONY += modules_prepare
1436modules_prepare: prepare
1437	$(Q)$(MAKE) $(build)=scripts scripts/module.lds
1438
1439export modules_sign_only :=
1440
1441ifeq ($(CONFIG_MODULE_SIG),y)
1442PHONY += modules_sign
1443modules_sign: modules_install
1444	@:
1445
1446# modules_sign is a subset of modules_install.
1447# 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1448ifeq ($(filter modules_install,$(MAKECMDGOALS)),)
1449modules_sign_only := y
1450endif
1451endif
1452
1453modinst_pre :=
1454ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
1455modinst_pre := __modinst_pre
1456endif
1457
1458modules_install: $(modinst_pre)
1459PHONY += __modinst_pre
1460__modinst_pre:
1461	@rm -rf $(MODLIB)/kernel
1462	@rm -f $(MODLIB)/source
1463	@mkdir -p $(MODLIB)/kernel
1464	@ln -s $(abspath $(srctree)) $(MODLIB)/source
1465	@if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
1466		rm -f $(MODLIB)/build ; \
1467		ln -s $(CURDIR) $(MODLIB)/build ; \
1468	fi
1469	@sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order
1470	@cp -f modules.builtin $(MODLIB)/
1471	@cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
1472
1473endif # CONFIG_MODULES
1474
1475###
1476# Cleaning is done on three levels.
1477# make clean     Delete most generated files
1478#                Leave enough to build external modules
1479# make mrproper  Delete the current configuration, and all generated files
1480# make distclean Remove editor backup files, patch leftover files and the like
1481
1482# Directories & files removed with 'make clean'
1483CLEAN_FILES += include/ksym vmlinux.symvers modules-only.symvers \
1484	       modules.builtin modules.builtin.modinfo modules.nsdeps \
1485	       compile_commands.json .thinlto-cache
1486
1487# Directories & files removed with 'make mrproper'
1488MRPROPER_FILES += include/config include/generated          \
1489		  arch/$(SRCARCH)/include/generated .tmp_objdiff \
1490		  debian snap tar-install \
1491		  .config .config.old .version \
1492		  Module.symvers \
1493		  certs/signing_key.pem \
1494		  certs/x509.genkey \
1495		  vmlinux-gdb.py \
1496		  *.spec
1497
1498# clean - Delete most, but leave enough to build external modules
1499#
1500clean: rm-files := $(CLEAN_FILES)
1501
1502PHONY += archclean vmlinuxclean
1503
1504vmlinuxclean:
1505	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1506	$(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1507
1508clean: archclean vmlinuxclean resolve_btfids_clean
1509
1510# mrproper - Delete all generated files, including .config
1511#
1512mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1513mrproper-dirs      := $(addprefix _mrproper_,scripts)
1514
1515PHONY += $(mrproper-dirs) mrproper
1516$(mrproper-dirs):
1517	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1518
1519mrproper: clean $(mrproper-dirs)
1520	$(call cmd,rmfiles)
1521
1522# distclean
1523#
1524PHONY += distclean
1525
1526distclean: mrproper
1527	@find . $(RCS_FIND_IGNORE) \
1528		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1529		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
1530		-o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1531		-o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1532		-type f -print | xargs rm -f
1533
1534
1535# Packaging of the kernel to various formats
1536# ---------------------------------------------------------------------------
1537
1538%src-pkg: FORCE
1539	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1540%pkg: include/config/kernel.release FORCE
1541	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1542
1543# Brief documentation of the typical targets used
1544# ---------------------------------------------------------------------------
1545
1546boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1547boards := $(sort $(notdir $(boards)))
1548board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1549board-dirs := $(sort $(notdir $(board-dirs:/=)))
1550
1551PHONY += help
1552help:
1553	@echo  'Cleaning targets:'
1554	@echo  '  clean		  - Remove most generated files but keep the config and'
1555	@echo  '                    enough build support to build external modules'
1556	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
1557	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
1558	@echo  ''
1559	@echo  'Configuration targets:'
1560	@$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1561	@echo  ''
1562	@echo  'Other generic targets:'
1563	@echo  '  all		  - Build all targets marked with [*]'
1564	@echo  '* vmlinux	  - Build the bare kernel'
1565	@echo  '* modules	  - Build all modules'
1566	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1567	@echo  '  dir/            - Build all files in dir and below'
1568	@echo  '  dir/file.[ois]  - Build specified target only'
1569	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1570	@echo  '                    (requires compiler support for LLVM assembly generation)'
1571	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1572	@echo  '                    (requires a recent binutils and recent build (System.map))'
1573	@echo  '  dir/file.ko     - Build module including final link'
1574	@echo  '  modules_prepare - Set up for building external modules'
1575	@echo  '  tags/TAGS	  - Generate tags file for editors'
1576	@echo  '  cscope	  - Generate cscope index'
1577	@echo  '  gtags           - Generate GNU GLOBAL index'
1578	@echo  '  kernelrelease	  - Output the release version string (use with make -s)'
1579	@echo  '  kernelversion	  - Output the version stored in Makefile (use with make -s)'
1580	@echo  '  image_name	  - Output the image name (use with make -s)'
1581	@echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1582	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1583	 echo  ''
1584	@echo  'Static analysers:'
1585	@echo  '  checkstack      - Generate a list of stack hogs'
1586	@echo  '  versioncheck    - Sanity check on version.h usage'
1587	@echo  '  includecheck    - Check for duplicate included header files'
1588	@echo  '  export_report   - List the usages of all exported symbols'
1589	@echo  '  headerdep       - Detect inclusion cycles in headers'
1590	@echo  '  coccicheck      - Check with Coccinelle'
1591	@echo  '  clang-analyzer  - Check with clang static analyzer'
1592	@echo  '  clang-tidy      - Check with clang-tidy'
1593	@echo  ''
1594	@echo  'Tools:'
1595	@echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1596	@echo  ''
1597	@echo  'Kernel selftest:'
1598	@echo  '  kselftest         - Build and run kernel selftest'
1599	@echo  '                      Build, install, and boot kernel before'
1600	@echo  '                      running kselftest on it'
1601	@echo  '                      Run as root for full coverage'
1602	@echo  '  kselftest-all     - Build kernel selftest'
1603	@echo  '  kselftest-install - Build and install kernel selftest'
1604	@echo  '  kselftest-clean   - Remove all generated kselftest files'
1605	@echo  '  kselftest-merge   - Merge all the config dependencies of'
1606	@echo  '		      kselftest to existing .config.'
1607	@echo  ''
1608	@$(if $(dtstree), \
1609		echo 'Devicetree:'; \
1610		echo '* dtbs             - Build device tree blobs for enabled boards'; \
1611		echo '  dtbs_install     - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1612		echo '  dt_binding_check - Validate device tree binding documents'; \
1613		echo '  dtbs_check       - Validate device tree source files';\
1614		echo '')
1615
1616	@echo 'Userspace tools targets:'
1617	@echo '  use "make tools/help"'
1618	@echo '  or  "cd tools; make help"'
1619	@echo  ''
1620	@echo  'Kernel packaging:'
1621	@$(MAKE) -f $(srctree)/scripts/Makefile.package help
1622	@echo  ''
1623	@echo  'Documentation targets:'
1624	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1625	@echo  ''
1626	@echo  'Architecture specific targets ($(SRCARCH)):'
1627	@$(or $(archhelp),\
1628		echo '  No architecture specific help defined for $(SRCARCH)')
1629	@echo  ''
1630	@$(if $(boards), \
1631		$(foreach b, $(boards), \
1632		printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1633		echo '')
1634	@$(if $(board-dirs), \
1635		$(foreach b, $(board-dirs), \
1636		printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1637		printf "  %-16s - Show all of the above\\n" help-boards; \
1638		echo '')
1639
1640	@echo  '  make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1641	@echo  '  make V=2   [targets] 2 => give reason for rebuild of target'
1642	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1643	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1644	@echo  '                       (sparse by default)'
1645	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1646	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1647	@echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
1648	@echo  '		1: warnings which may be relevant and do not occur too often'
1649	@echo  '		2: warnings which occur quite often but may still be relevant'
1650	@echo  '		3: more obscure warnings, can most likely be ignored'
1651	@echo  '		Multiple levels can be combined with W=12 or W=123'
1652	@echo  ''
1653	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
1654	@echo  'For further info see the ./README file'
1655
1656
1657help-board-dirs := $(addprefix help-,$(board-dirs))
1658
1659help-boards: $(help-board-dirs)
1660
1661boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1662
1663$(help-board-dirs): help-%:
1664	@echo  'Architecture specific targets ($(SRCARCH) $*):'
1665	@$(if $(boards-per-dir), \
1666		$(foreach b, $(boards-per-dir), \
1667		printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1668		echo '')
1669
1670
1671# Documentation targets
1672# ---------------------------------------------------------------------------
1673DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1674	       linkcheckdocs dochelp refcheckdocs
1675PHONY += $(DOC_TARGETS)
1676$(DOC_TARGETS):
1677	$(Q)$(MAKE) $(build)=Documentation $@
1678
1679# Misc
1680# ---------------------------------------------------------------------------
1681
1682PHONY += scripts_gdb
1683scripts_gdb: prepare0
1684	$(Q)$(MAKE) $(build)=scripts/gdb
1685	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1686
1687ifdef CONFIG_GDB_SCRIPTS
1688all: scripts_gdb
1689endif
1690
1691else # KBUILD_EXTMOD
1692
1693###
1694# External module support.
1695# When building external modules the kernel used as basis is considered
1696# read-only, and no consistency checks are made and the make
1697# system is not used on the basis kernel. If updates are required
1698# in the basis kernel ordinary make commands (without M=...) must be used.
1699
1700# We are always building only modules.
1701KBUILD_BUILTIN :=
1702KBUILD_MODULES := 1
1703
1704build-dirs := $(KBUILD_EXTMOD)
1705$(MODORDER): descend
1706	@:
1707
1708compile_commands.json: $(extmod_prefix)compile_commands.json
1709PHONY += compile_commands.json
1710
1711clean-dirs := $(KBUILD_EXTMOD)
1712clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1713	$(KBUILD_EXTMOD)/compile_commands.json $(KBUILD_EXTMOD)/.thinlto-cache
1714
1715PHONY += prepare
1716# now expand this into a simple variable to reduce the cost of shell evaluations
1717prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT)
1718prepare:
1719	@if [ "$(CC_VERSION_TEXT)" != "$(CONFIG_CC_VERSION_TEXT)" ]; then \
1720		echo >&2 "warning: the compiler differs from the one used to build the kernel"; \
1721		echo >&2 "  The kernel was built by: $(CONFIG_CC_VERSION_TEXT)"; \
1722		echo >&2 "  You are using:           $(CC_VERSION_TEXT)"; \
1723	fi
1724
1725PHONY += help
1726help:
1727	@echo  '  Building external modules.'
1728	@echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1729	@echo  ''
1730	@echo  '  modules         - default target, build the module(s)'
1731	@echo  '  modules_install - install the module'
1732	@echo  '  clean           - remove generated files in module directory only'
1733	@echo  ''
1734
1735# no-op for external module builds
1736PHONY += modules_prepare
1737
1738endif # KBUILD_EXTMOD
1739
1740# ---------------------------------------------------------------------------
1741# Modules
1742
1743PHONY += modules modules_install
1744
1745ifdef CONFIG_MODULES
1746
1747modules: modules_check
1748	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1749
1750PHONY += modules_check
1751modules_check: $(MODORDER)
1752	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1753
1754quiet_cmd_depmod = DEPMOD  $(MODLIB)
1755      cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1756                   $(KERNELRELEASE)
1757
1758modules_install:
1759	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1760	$(call cmd,depmod)
1761
1762else # CONFIG_MODULES
1763
1764# Modules not configured
1765# ---------------------------------------------------------------------------
1766
1767modules modules_install:
1768	@echo >&2 '***'
1769	@echo >&2 '*** The present kernel configuration has modules disabled.'
1770	@echo >&2 '*** To use the module feature, please run "make menuconfig" etc.'
1771	@echo >&2 '*** to enable CONFIG_MODULES.'
1772	@echo >&2 '***'
1773	@exit 1
1774
1775endif # CONFIG_MODULES
1776
1777# Single targets
1778# ---------------------------------------------------------------------------
1779# To build individual files in subdirectories, you can do like this:
1780#
1781#   make foo/bar/baz.s
1782#
1783# The supported suffixes for single-target are listed in 'single-targets'
1784#
1785# To build only under specific subdirectories, you can do like this:
1786#
1787#   make foo/bar/baz/
1788
1789ifdef single-build
1790
1791# .ko is special because modpost is needed
1792single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1793single-no-ko := $(sort $(patsubst %.ko,%.mod, $(MAKECMDGOALS)))
1794
1795$(single-ko): single_modpost
1796	@:
1797$(single-no-ko): descend
1798	@:
1799
1800ifeq ($(KBUILD_EXTMOD),)
1801# For the single build of in-tree modules, use a temporary file to avoid
1802# the situation of modules_install installing an invalid modules.order.
1803MODORDER := .modules.tmp
1804endif
1805
1806PHONY += single_modpost
1807single_modpost: $(single-no-ko) modules_prepare
1808	$(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$m;) } > $(MODORDER)
1809	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1810
1811KBUILD_MODULES := 1
1812
1813export KBUILD_SINGLE_TARGETS := $(addprefix $(extmod_prefix), $(single-no-ko))
1814
1815# trim unrelated directories
1816build-dirs := $(foreach d, $(build-dirs), \
1817			$(if $(filter $(d)/%, $(KBUILD_SINGLE_TARGETS)), $(d)))
1818
1819endif
1820
1821ifndef CONFIG_MODULES
1822KBUILD_MODULES :=
1823endif
1824
1825# Handle descending into subdirectories listed in $(build-dirs)
1826# Preset locale variables to speed up the build process. Limit locale
1827# tweaks to this spot to avoid wrong language settings when running
1828# make menuconfig etc.
1829# Error messages still appears in the original language
1830PHONY += descend $(build-dirs)
1831descend: $(build-dirs)
1832$(build-dirs): prepare
1833	$(Q)$(MAKE) $(build)=$@ \
1834	single-build=$(if $(filter-out $@/, $(filter $@/%, $(KBUILD_SINGLE_TARGETS))),1) \
1835	need-builtin=1 need-modorder=1
1836
1837clean-dirs := $(addprefix _clean_, $(clean-dirs))
1838PHONY += $(clean-dirs) clean
1839$(clean-dirs):
1840	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1841
1842clean: $(clean-dirs)
1843	$(call cmd,rmfiles)
1844	@find $(or $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1845		\( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1846		-o -name '*.ko.*' \
1847		-o -name '*.dtb' -o -name '*.dtbo' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1848		-o -name '*.dwo' -o -name '*.lst' \
1849		-o -name '*.su' -o -name '*.mod' \
1850		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1851		-o -name '*.lex.c' -o -name '*.tab.[ch]' \
1852		-o -name '*.asn1.[ch]' \
1853		-o -name '*.symtypes' -o -name 'modules.order' \
1854		-o -name '.tmp_*.o.*' \
1855		-o -name '*.c.[012]*.*' \
1856		-o -name '*.ll' \
1857		-o -name '*.gcno' \
1858		-o -name '*.*.symversions' \) -type f -print | xargs rm -f
1859
1860# Generate tags for editors
1861# ---------------------------------------------------------------------------
1862quiet_cmd_tags = GEN     $@
1863      cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1864
1865tags TAGS cscope gtags: FORCE
1866	$(call cmd,tags)
1867
1868# Script to generate missing namespace dependencies
1869# ---------------------------------------------------------------------------
1870
1871PHONY += nsdeps
1872nsdeps: export KBUILD_NSDEPS=1
1873nsdeps: modules
1874	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1875
1876# Clang Tooling
1877# ---------------------------------------------------------------------------
1878
1879quiet_cmd_gen_compile_commands = GEN     $@
1880      cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
1881
1882$(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
1883	$(if $(KBUILD_EXTMOD),,$(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)) \
1884	$(if $(CONFIG_MODULES), $(MODORDER)) FORCE
1885	$(call if_changed,gen_compile_commands)
1886
1887targets += $(extmod_prefix)compile_commands.json
1888
1889PHONY += clang-tidy clang-analyzer
1890
1891ifdef CONFIG_CC_IS_CLANG
1892quiet_cmd_clang_tools = CHECK   $<
1893      cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
1894
1895clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
1896	$(call cmd,clang_tools)
1897else
1898clang-tidy clang-analyzer:
1899	@echo "$@ requires CC=clang" >&2
1900	@false
1901endif
1902
1903# Scripts to check various things for consistency
1904# ---------------------------------------------------------------------------
1905
1906PHONY += includecheck versioncheck coccicheck export_report
1907
1908includecheck:
1909	find $(srctree)/* $(RCS_FIND_IGNORE) \
1910		-name '*.[hcS]' -type f -print | sort \
1911		| xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1912
1913versioncheck:
1914	find $(srctree)/* $(RCS_FIND_IGNORE) \
1915		-name '*.[hcS]' -type f -print | sort \
1916		| xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1917
1918coccicheck:
1919	$(Q)$(BASH) $(srctree)/scripts/$@
1920
1921export_report:
1922	$(PERL) $(srctree)/scripts/export_report.pl
1923
1924PHONY += checkstack kernelrelease kernelversion image_name
1925
1926# UML needs a little special treatment here.  It wants to use the host
1927# toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
1928# else wants $(ARCH), including people doing cross-builds, which means
1929# that $(SUBARCH) doesn't work here.
1930ifeq ($(ARCH), um)
1931CHECKSTACK_ARCH := $(SUBARCH)
1932else
1933CHECKSTACK_ARCH := $(ARCH)
1934endif
1935checkstack:
1936	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1937	$(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1938
1939kernelrelease:
1940	@echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1941
1942kernelversion:
1943	@echo $(KERNELVERSION)
1944
1945image_name:
1946	@echo $(KBUILD_IMAGE)
1947
1948quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
1949      cmd_rmfiles = rm -rf $(rm-files)
1950
1951# read saved command lines for existing targets
1952existing-targets := $(wildcard $(sort $(targets)))
1953
1954-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
1955
1956endif # config-build
1957endif # mixed-build
1958endif # need-sub-make
1959
1960PHONY += FORCE
1961FORCE:
1962
1963# Declare the contents of the PHONY variable as phony.  We keep that
1964# information in a variable so we can use it in if_changed and friends.
1965.PHONY: $(PHONY)
1966