xref: /openbmc/linux/Makefile (revision 5f8b7d4b2e9604d03ae06f1a2dd5a1f34c33e533)
1 # SPDX-License-Identifier: GPL-2.0
2 VERSION = 6
3 PATCHLEVEL = 6
4 SUBLEVEL = 60
5 EXTRAVERSION =
6 NAME = Pinguïn Aangedreven
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 ifeq ($(filter undefine,$(.FEATURES)),)
15 $(error GNU Make >= 3.82 is required. Your Make version is $(MAKE_VERSION))
16 endif
17 
18 $(if $(filter __%, $(MAKECMDGOALS)), \
19 	$(error targets prefixed with '__' are only for internal use))
20 
21 # That's our default target when none is given on the command line
22 PHONY := __all
23 __all:
24 
25 # We are using a recursive build, so we need to do a little thinking
26 # to get the ordering right.
27 #
28 # Most importantly: sub-Makefiles should only ever modify files in
29 # their own directory. If in some directory we have a dependency on
30 # a file in another dir (which doesn't happen often, but it's often
31 # unavoidable when linking the built-in.a targets which finally
32 # turn into vmlinux), we will call a sub make in that other dir, and
33 # after that we are sure that everything which is in that other dir
34 # is now up to date.
35 #
36 # The only cases where we need to modify files which have global
37 # effects are thus separated out and done before the recursive
38 # descending is started. They are now explicitly listed as the
39 # prepare rule.
40 
41 this-makefile := $(lastword $(MAKEFILE_LIST))
42 export abs_srctree := $(realpath $(dir $(this-makefile)))
43 export abs_objtree := $(CURDIR)
44 
45 ifneq ($(sub_make_done),1)
46 
47 # Do not use make's built-in rules and variables
48 # (this increases performance and avoids hard-to-debug behaviour)
49 MAKEFLAGS += -rR
50 
51 # Avoid funny character set dependencies
52 unexport LC_ALL
53 LC_COLLATE=C
54 LC_NUMERIC=C
55 export LC_COLLATE LC_NUMERIC
56 
57 # Avoid interference with shell env settings
58 unexport GREP_OPTIONS
59 
60 # Beautify output
61 # ---------------------------------------------------------------------------
62 #
63 # Most of build commands in Kbuild start with "cmd_". You can optionally define
64 # "quiet_cmd_*". If defined, the short log is printed. Otherwise, no log from
65 # that command is printed by default.
66 #
67 # e.g.)
68 #    quiet_cmd_depmod = DEPMOD  $(MODLIB)
69 #          cmd_depmod = $(srctree)/scripts/depmod.sh $(DEPMOD) $(KERNELRELEASE)
70 #
71 # A simple variant is to prefix commands with $(Q) - that's useful
72 # for commands that shall be hidden in non-verbose mode.
73 #
74 #    $(Q)$(MAKE) $(build)=scripts/basic
75 #
76 # If KBUILD_VERBOSE contains 1, the whole command is echoed.
77 # If KBUILD_VERBOSE contains 2, the reason for rebuilding is printed.
78 #
79 # To put more focus on warnings, be less verbose as default
80 # Use 'make V=1' to see the full commands
81 
82 ifeq ("$(origin V)", "command line")
83   KBUILD_VERBOSE = $(V)
84 endif
85 
86 quiet = quiet_
87 Q = @
88 
89 ifneq ($(findstring 1, $(KBUILD_VERBOSE)),)
90   quiet =
91   Q =
92 endif
93 
94 # If the user is running make -s (silent mode), suppress echoing of
95 # commands
96 # make-4.0 (and later) keep single letter options in the 1st word of MAKEFLAGS.
97 
98 ifeq ($(filter 3.%,$(MAKE_VERSION)),)
99 short-opts := $(firstword -$(MAKEFLAGS))
100 else
101 short-opts := $(filter-out --%,$(MAKEFLAGS))
102 endif
103 
104 ifneq ($(findstring s,$(short-opts)),)
105 quiet=silent_
106 override KBUILD_VERBOSE :=
107 endif
108 
109 export quiet Q KBUILD_VERBOSE
110 
111 # Call a source code checker (by default, "sparse") as part of the
112 # C compilation.
113 #
114 # Use 'make C=1' to enable checking of only re-compiled files.
115 # Use 'make C=2' to enable checking of *all* source files, regardless
116 # of whether they are re-compiled or not.
117 #
118 # See the file "Documentation/dev-tools/sparse.rst" for more details,
119 # including where to get the "sparse" utility.
120 
121 ifeq ("$(origin C)", "command line")
122   KBUILD_CHECKSRC = $(C)
123 endif
124 ifndef KBUILD_CHECKSRC
125   KBUILD_CHECKSRC = 0
126 endif
127 
128 export KBUILD_CHECKSRC
129 
130 # Enable "clippy" (a linter) as part of the Rust compilation.
131 #
132 # Use 'make CLIPPY=1' to enable it.
133 ifeq ("$(origin CLIPPY)", "command line")
134   KBUILD_CLIPPY := $(CLIPPY)
135 endif
136 
137 export KBUILD_CLIPPY
138 
139 # Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
140 # directory of external module to build. Setting M= takes precedence.
141 ifeq ("$(origin M)", "command line")
142   KBUILD_EXTMOD := $(M)
143 endif
144 
145 $(if $(word 2, $(KBUILD_EXTMOD)), \
146 	$(error building multiple external modules is not supported))
147 
148 $(foreach x, % :, $(if $(findstring $x, $(KBUILD_EXTMOD)), \
149 	$(error module directory path cannot contain '$x')))
150 
151 # Remove trailing slashes
152 ifneq ($(filter %/, $(KBUILD_EXTMOD)),)
153 KBUILD_EXTMOD := $(shell dirname $(KBUILD_EXTMOD).)
154 endif
155 
156 export KBUILD_EXTMOD
157 
158 # Kbuild will save output files in the current working directory.
159 # This does not need to match to the root of the kernel source tree.
160 #
161 # For example, you can do this:
162 #
163 #  cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
164 #
165 # If you want to save output files in a different location, there are
166 # two syntaxes to specify it.
167 #
168 # 1) O=
169 # Use "make O=dir/to/store/output/files/"
170 #
171 # 2) Set KBUILD_OUTPUT
172 # Set the environment variable KBUILD_OUTPUT to point to the output directory.
173 # export KBUILD_OUTPUT=dir/to/store/output/files/; make
174 #
175 # The O= assignment takes precedence over the KBUILD_OUTPUT environment
176 # variable.
177 
178 # Do we want to change the working directory?
179 ifeq ("$(origin O)", "command line")
180   KBUILD_OUTPUT := $(O)
181 endif
182 
183 ifneq ($(KBUILD_OUTPUT),)
184 # Make's built-in functions such as $(abspath ...), $(realpath ...) cannot
185 # expand a shell special character '~'. We use a somewhat tedious way here.
186 abs_objtree := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) && pwd)
187 $(if $(abs_objtree),, \
188      $(error failed to create output directory "$(KBUILD_OUTPUT)"))
189 
190 # $(realpath ...) resolves symlinks
191 abs_objtree := $(realpath $(abs_objtree))
192 endif # ifneq ($(KBUILD_OUTPUT),)
193 
194 ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
195 $(error source directory cannot contain spaces or colons)
196 endif
197 
198 ifneq ($(filter 3.%,$(MAKE_VERSION)),)
199 # 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
200 # We need to invoke sub-make to avoid implicit rules in the top Makefile.
201 need-sub-make := 1
202 # Cancel implicit rules for this Makefile.
203 $(this-makefile): ;
204 endif
205 
206 export sub_make_done := 1
207 
208 endif # sub_make_done
209 
210 ifeq ($(abs_objtree),$(CURDIR))
211 # Suppress "Entering directory ..." if we are at the final work directory.
212 no-print-directory := --no-print-directory
213 else
214 # Recursion to show "Entering directory ..."
215 need-sub-make := 1
216 endif
217 
218 ifeq ($(filter --no-print-directory, $(MAKEFLAGS)),)
219 # If --no-print-directory is unset, recurse once again to set it.
220 # You may end up recursing into __sub-make twice. This is needed due to the
221 # behavior change in GNU Make 4.4.1.
222 need-sub-make := 1
223 endif
224 
225 ifeq ($(need-sub-make),1)
226 
227 PHONY += $(MAKECMDGOALS) __sub-make
228 
229 $(filter-out $(this-makefile), $(MAKECMDGOALS)) __all: __sub-make
230 	@:
231 
232 # Invoke a second make in the output directory, passing relevant variables
233 __sub-make:
234 	$(Q)$(MAKE) $(no-print-directory) -C $(abs_objtree) \
235 	-f $(abs_srctree)/Makefile $(MAKECMDGOALS)
236 
237 else # need-sub-make
238 
239 # We process the rest of the Makefile if this is the final invocation of make
240 
241 ifeq ($(abs_srctree),$(abs_objtree))
242         # building in the source tree
243         srctree := .
244 	building_out_of_srctree :=
245 else
246         ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
247                 # building in a subdirectory of the source tree
248                 srctree := ..
249         else
250                 srctree := $(abs_srctree)
251         endif
252 	building_out_of_srctree := 1
253 endif
254 
255 ifneq ($(KBUILD_ABS_SRCTREE),)
256 srctree := $(abs_srctree)
257 endif
258 
259 objtree		:= .
260 VPATH		:= $(srctree)
261 
262 export building_out_of_srctree srctree objtree VPATH
263 
264 # To make sure we do not include .config for any of the *config targets
265 # catch them early, and hand them over to scripts/kconfig/Makefile
266 # It is allowed to specify more targets when calling make, including
267 # mixing *config targets and build targets.
268 # For example 'make oldconfig all'.
269 # Detect when mixed targets is specified, and make a second invocation
270 # of make so .config is not included in this case either (for *config).
271 
272 version_h := include/generated/uapi/linux/version.h
273 
274 clean-targets := %clean mrproper cleandocs
275 no-dot-config-targets := $(clean-targets) \
276 			 cscope gtags TAGS tags help% %docs check% coccicheck \
277 			 $(version_h) headers headers_% archheaders archscripts \
278 			 %asm-generic kernelversion %src-pkg dt_binding_check \
279 			 outputmakefile rustavailable rustfmt rustfmtcheck
280 # Installation targets should not require compiler. Unfortunately, vdso_install
281 # is an exception where build artifacts may be updated. This must be fixed.
282 no-compiler-targets := $(no-dot-config-targets) install dtbs_install \
283 			headers_install modules_install modules_sign kernelrelease image_name
284 no-sync-config-targets := $(no-dot-config-targets) %install modules_sign kernelrelease \
285 			  image_name
286 single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.rsi %.s %.symtypes %/
287 
288 config-build	:=
289 mixed-build	:=
290 need-config	:= 1
291 need-compiler	:= 1
292 may-sync-config	:= 1
293 single-build	:=
294 
295 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
296 	ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
297 		need-config :=
298 	endif
299 endif
300 
301 ifneq ($(filter $(no-compiler-targets), $(MAKECMDGOALS)),)
302 	ifeq ($(filter-out $(no-compiler-targets), $(MAKECMDGOALS)),)
303 		need-compiler :=
304 	endif
305 endif
306 
307 ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
308 	ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
309 		may-sync-config :=
310 	endif
311 endif
312 
313 ifneq ($(KBUILD_EXTMOD),)
314 	may-sync-config :=
315 endif
316 
317 ifeq ($(KBUILD_EXTMOD),)
318         ifneq ($(filter %config,$(MAKECMDGOALS)),)
319 		config-build := 1
320                 ifneq ($(words $(MAKECMDGOALS)),1)
321 			mixed-build := 1
322                 endif
323         endif
324 endif
325 
326 # We cannot build single targets and the others at the same time
327 ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
328 	single-build := 1
329 	ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
330 		mixed-build := 1
331 	endif
332 endif
333 
334 # For "make -j clean all", "make -j mrproper defconfig all", etc.
335 ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
336         ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
337 		mixed-build := 1
338         endif
339 endif
340 
341 # install and modules_install need also be processed one by one
342 ifneq ($(filter install,$(MAKECMDGOALS)),)
343         ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
344 		mixed-build := 1
345         endif
346 endif
347 
348 ifdef mixed-build
349 # ===========================================================================
350 # We're called with mixed targets (*config and build targets).
351 # Handle them one by one.
352 
353 PHONY += $(MAKECMDGOALS) __build_one_by_one
354 
355 $(MAKECMDGOALS): __build_one_by_one
356 	@:
357 
358 __build_one_by_one:
359 	$(Q)set -e; \
360 	for i in $(MAKECMDGOALS); do \
361 		$(MAKE) -f $(srctree)/Makefile $$i; \
362 	done
363 
364 else # !mixed-build
365 
366 include $(srctree)/scripts/Kbuild.include
367 
368 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
369 KERNELRELEASE = $(call read-file, include/config/kernel.release)
370 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
371 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
372 
373 include $(srctree)/scripts/subarch.include
374 
375 # Cross compiling and selecting different set of gcc/bin-utils
376 # ---------------------------------------------------------------------------
377 #
378 # When performing cross compilation for other architectures ARCH shall be set
379 # to the target architecture. (See arch/* for the possibilities).
380 # ARCH can be set during invocation of make:
381 # make ARCH=ia64
382 # Another way is to have ARCH set in the environment.
383 # The default ARCH is the host where make is executed.
384 
385 # CROSS_COMPILE specify the prefix used for all executables used
386 # during compilation. Only gcc and related bin-utils executables
387 # are prefixed with $(CROSS_COMPILE).
388 # CROSS_COMPILE can be set on the command line
389 # make CROSS_COMPILE=ia64-linux-
390 # Alternatively CROSS_COMPILE can be set in the environment.
391 # Default value for CROSS_COMPILE is not to prefix executables
392 # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
393 ARCH		?= $(SUBARCH)
394 
395 # Architecture as present in compile.h
396 UTS_MACHINE 	:= $(ARCH)
397 SRCARCH 	:= $(ARCH)
398 
399 # Additional ARCH settings for x86
400 ifeq ($(ARCH),i386)
401         SRCARCH := x86
402 endif
403 ifeq ($(ARCH),x86_64)
404         SRCARCH := x86
405 endif
406 
407 # Additional ARCH settings for sparc
408 ifeq ($(ARCH),sparc32)
409        SRCARCH := sparc
410 endif
411 ifeq ($(ARCH),sparc64)
412        SRCARCH := sparc
413 endif
414 
415 # Additional ARCH settings for parisc
416 ifeq ($(ARCH),parisc64)
417        SRCARCH := parisc
418 endif
419 
420 export cross_compiling :=
421 ifneq ($(SRCARCH),$(SUBARCH))
422 cross_compiling := 1
423 endif
424 
425 KCONFIG_CONFIG	?= .config
426 export KCONFIG_CONFIG
427 
428 # SHELL used by kbuild
429 CONFIG_SHELL := sh
430 
431 HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
432 HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
433 HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
434 
435 ifneq ($(LLVM),)
436 ifneq ($(filter %/,$(LLVM)),)
437 LLVM_PREFIX := $(LLVM)
438 else ifneq ($(filter -%,$(LLVM)),)
439 LLVM_SUFFIX := $(LLVM)
440 endif
441 
442 HOSTCC	= $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
443 HOSTCXX	= $(LLVM_PREFIX)clang++$(LLVM_SUFFIX)
444 else
445 HOSTCC	= gcc
446 HOSTCXX	= g++
447 endif
448 HOSTRUSTC = rustc
449 HOSTPKG_CONFIG	= pkg-config
450 
451 KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
452 			 -O2 -fomit-frame-pointer -std=gnu11
453 KBUILD_USERCFLAGS  := $(KBUILD_USERHOSTCFLAGS) $(USERCFLAGS)
454 KBUILD_USERLDFLAGS := $(USERLDFLAGS)
455 
456 # These flags apply to all Rust code in the tree, including the kernel and
457 # host programs.
458 export rust_common_flags := --edition=2021 \
459 			    -Zbinary_dep_depinfo=y \
460 			    -Dunsafe_op_in_unsafe_fn -Drust_2018_idioms \
461 			    -Dunreachable_pub -Dnon_ascii_idents \
462 			    -Wmissing_docs \
463 			    -Drustdoc::missing_crate_level_docs \
464 			    -Dclippy::correctness -Dclippy::style \
465 			    -Dclippy::suspicious -Dclippy::complexity \
466 			    -Dclippy::perf \
467 			    -Dclippy::let_unit_value -Dclippy::mut_mut \
468 			    -Dclippy::needless_bitwise_bool \
469 			    -Dclippy::needless_continue \
470 			    -Dclippy::no_mangle_with_rust_abi \
471 			    -Wclippy::dbg_macro
472 
473 KBUILD_HOSTCFLAGS   := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
474 KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
475 KBUILD_HOSTRUSTFLAGS := $(rust_common_flags) -O -Cstrip=debuginfo \
476 			-Zallow-features= $(HOSTRUSTFLAGS)
477 KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
478 KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
479 
480 # Make variables (CC, etc...)
481 CPP		= $(CC) -E
482 ifneq ($(LLVM),)
483 CC		= $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
484 LD		= $(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX)
485 AR		= $(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX)
486 NM		= $(LLVM_PREFIX)llvm-nm$(LLVM_SUFFIX)
487 OBJCOPY		= $(LLVM_PREFIX)llvm-objcopy$(LLVM_SUFFIX)
488 OBJDUMP		= $(LLVM_PREFIX)llvm-objdump$(LLVM_SUFFIX)
489 READELF		= $(LLVM_PREFIX)llvm-readelf$(LLVM_SUFFIX)
490 STRIP		= $(LLVM_PREFIX)llvm-strip$(LLVM_SUFFIX)
491 else
492 CC		= $(CROSS_COMPILE)gcc
493 LD		= $(CROSS_COMPILE)ld
494 AR		= $(CROSS_COMPILE)ar
495 NM		= $(CROSS_COMPILE)nm
496 OBJCOPY		= $(CROSS_COMPILE)objcopy
497 OBJDUMP		= $(CROSS_COMPILE)objdump
498 READELF		= $(CROSS_COMPILE)readelf
499 STRIP		= $(CROSS_COMPILE)strip
500 endif
501 RUSTC		= rustc
502 RUSTDOC		= rustdoc
503 RUSTFMT		= rustfmt
504 CLIPPY_DRIVER	= clippy-driver
505 BINDGEN		= bindgen
506 CARGO		= cargo
507 PAHOLE		= pahole
508 RESOLVE_BTFIDS	= $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
509 LEX		= flex
510 YACC		= bison
511 AWK		= awk
512 INSTALLKERNEL  := installkernel
513 PERL		= perl
514 PYTHON3		= python3
515 CHECK		= sparse
516 BASH		= bash
517 KGZIP		= gzip
518 KBZIP2		= bzip2
519 KLZOP		= lzop
520 LZMA		= lzma
521 LZ4		= lz4c
522 XZ		= xz
523 ZSTD		= zstd
524 
525 PAHOLE_FLAGS	= $(shell PAHOLE=$(PAHOLE) $(srctree)/scripts/pahole-flags.sh)
526 
527 CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
528 		  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
529 NOSTDINC_FLAGS :=
530 CFLAGS_MODULE   =
531 RUSTFLAGS_MODULE =
532 AFLAGS_MODULE   =
533 LDFLAGS_MODULE  =
534 CFLAGS_KERNEL	=
535 RUSTFLAGS_KERNEL =
536 AFLAGS_KERNEL	=
537 LDFLAGS_vmlinux =
538 
539 # Use USERINCLUDE when you must reference the UAPI directories only.
540 USERINCLUDE    := \
541 		-I$(srctree)/arch/$(SRCARCH)/include/uapi \
542 		-I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
543 		-I$(srctree)/include/uapi \
544 		-I$(objtree)/include/generated/uapi \
545                 -include $(srctree)/include/linux/compiler-version.h \
546                 -include $(srctree)/include/linux/kconfig.h
547 
548 # Use LINUXINCLUDE when you must reference the include/ directory.
549 # Needed to be compatible with the O= option
550 LINUXINCLUDE    := \
551 		-I$(srctree)/arch/$(SRCARCH)/include \
552 		-I$(objtree)/arch/$(SRCARCH)/include/generated \
553 		$(if $(building_out_of_srctree),-I$(srctree)/include) \
554 		-I$(objtree)/include \
555 		$(USERINCLUDE)
556 
557 KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
558 
559 KBUILD_CFLAGS :=
560 KBUILD_CFLAGS += -std=gnu11
561 KBUILD_CFLAGS += -fshort-wchar
562 KBUILD_CFLAGS += -funsigned-char
563 KBUILD_CFLAGS += -fno-common
564 KBUILD_CFLAGS += -fno-PIE
565 KBUILD_CFLAGS += -fno-strict-aliasing
566 
567 KBUILD_CPPFLAGS := -D__KERNEL__
568 KBUILD_RUSTFLAGS := $(rust_common_flags) \
569 		    --target=$(objtree)/scripts/target.json \
570 		    -Cpanic=abort -Cembed-bitcode=n -Clto=n \
571 		    -Cforce-unwind-tables=n -Ccodegen-units=1 \
572 		    -Csymbol-mangling-version=v0 \
573 		    -Crelocation-model=static \
574 		    -Zfunction-sections=n \
575 		    -Dclippy::float_arithmetic
576 
577 KBUILD_AFLAGS_KERNEL :=
578 KBUILD_CFLAGS_KERNEL :=
579 KBUILD_RUSTFLAGS_KERNEL :=
580 KBUILD_AFLAGS_MODULE  := -DMODULE
581 KBUILD_CFLAGS_MODULE  := -DMODULE
582 KBUILD_RUSTFLAGS_MODULE := --cfg MODULE
583 KBUILD_LDFLAGS_MODULE :=
584 KBUILD_LDFLAGS :=
585 CLANG_FLAGS :=
586 
587 ifeq ($(KBUILD_CLIPPY),1)
588 	RUSTC_OR_CLIPPY_QUIET := CLIPPY
589 	RUSTC_OR_CLIPPY = $(CLIPPY_DRIVER)
590 else
591 	RUSTC_OR_CLIPPY_QUIET := RUSTC
592 	RUSTC_OR_CLIPPY = $(RUSTC)
593 endif
594 
595 ifdef RUST_LIB_SRC
596 	export RUST_LIB_SRC
597 endif
598 
599 # Allows the usage of unstable features in stable compilers.
600 export RUSTC_BOOTSTRAP := 1
601 
602 export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG
603 export RUSTC RUSTDOC RUSTFMT RUSTC_OR_CLIPPY_QUIET RUSTC_OR_CLIPPY BINDGEN CARGO
604 export HOSTRUSTC KBUILD_HOSTRUSTFLAGS
605 export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
606 export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
607 export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
608 export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
609 export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS
610 
611 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
612 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
613 export KBUILD_RUSTFLAGS RUSTFLAGS_KERNEL RUSTFLAGS_MODULE
614 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
615 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_RUSTFLAGS_MODULE KBUILD_LDFLAGS_MODULE
616 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL KBUILD_RUSTFLAGS_KERNEL
617 export PAHOLE_FLAGS
618 
619 # Files to ignore in find ... statements
620 
621 export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
622 			  -name CVS -o -name .pc -o -name .hg -o -name .git \) \
623 			  -prune -o
624 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
625 			 --exclude CVS --exclude .pc --exclude .hg --exclude .git
626 
627 # ===========================================================================
628 # Rules shared between *config targets and build targets
629 
630 # Basic helpers built in scripts/basic/
631 PHONY += scripts_basic
632 scripts_basic:
633 	$(Q)$(MAKE) $(build)=scripts/basic
634 
635 PHONY += outputmakefile
636 ifdef building_out_of_srctree
637 # Before starting out-of-tree build, make sure the source tree is clean.
638 # outputmakefile generates a Makefile in the output directory, if using a
639 # separate output directory. This allows convenient use of make in the
640 # output directory.
641 # At the same time when output Makefile generated, generate .gitignore to
642 # ignore whole output directory
643 
644 quiet_cmd_makefile = GEN     Makefile
645       cmd_makefile = { \
646 	echo "\# Automatically generated by $(srctree)/Makefile: don't edit"; \
647 	echo "include $(srctree)/Makefile"; \
648 	} > Makefile
649 
650 outputmakefile:
651 	@if [ -f $(srctree)/.config -o \
652 		 -d $(srctree)/include/config -o \
653 		 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
654 		echo >&2 "***"; \
655 		echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
656 		echo >&2 "*** in $(abs_srctree)";\
657 		echo >&2 "***"; \
658 		false; \
659 	fi
660 	$(Q)ln -fsn $(srctree) source
661 	$(call cmd,makefile)
662 	$(Q)test -e .gitignore || \
663 	{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
664 endif
665 
666 # The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
667 # Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
668 # CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
669 # and from include/config/auto.conf.cmd to detect the compiler upgrade.
670 CC_VERSION_TEXT = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1))
671 
672 ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
673 include $(srctree)/scripts/Makefile.clang
674 endif
675 
676 # Include this also for config targets because some architectures need
677 # cc-cross-prefix to determine CROSS_COMPILE.
678 ifdef need-compiler
679 include $(srctree)/scripts/Makefile.compiler
680 endif
681 
682 ifdef config-build
683 # ===========================================================================
684 # *config targets only - make sure prerequisites are updated, and descend
685 # in scripts/kconfig to make the *config target
686 
687 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
688 # KBUILD_DEFCONFIG may point out an alternative default configuration
689 # used for 'make defconfig'
690 include $(srctree)/arch/$(SRCARCH)/Makefile
691 export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
692 
693 config: outputmakefile scripts_basic FORCE
694 	$(Q)$(MAKE) $(build)=scripts/kconfig $@
695 
696 %config: outputmakefile scripts_basic FORCE
697 	$(Q)$(MAKE) $(build)=scripts/kconfig $@
698 
699 else #!config-build
700 # ===========================================================================
701 # Build targets only - this includes vmlinux, arch specific targets, clean
702 # targets and others. In general all targets except *config targets.
703 
704 # If building an external module we do not care about the all: rule
705 # but instead __all depend on modules
706 PHONY += all
707 ifeq ($(KBUILD_EXTMOD),)
708 __all: all
709 else
710 __all: modules
711 endif
712 
713 targets :=
714 
715 # Decide whether to build built-in, modular, or both.
716 # Normally, just do built-in.
717 
718 KBUILD_MODULES :=
719 KBUILD_BUILTIN := 1
720 
721 # If we have only "make modules", don't compile built-in objects.
722 ifeq ($(MAKECMDGOALS),modules)
723   KBUILD_BUILTIN :=
724 endif
725 
726 # If we have "make <whatever> modules", compile modules
727 # in addition to whatever we do anyway.
728 # Just "make" or "make all" shall build modules as well
729 
730 ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
731   KBUILD_MODULES := 1
732 endif
733 
734 ifeq ($(MAKECMDGOALS),)
735   KBUILD_MODULES := 1
736 endif
737 
738 export KBUILD_MODULES KBUILD_BUILTIN
739 
740 ifdef need-config
741 include include/config/auto.conf
742 endif
743 
744 ifeq ($(KBUILD_EXTMOD),)
745 # Objects we will link into vmlinux / subdirs we need to visit
746 core-y		:=
747 drivers-y	:=
748 libs-y		:= lib/
749 endif # KBUILD_EXTMOD
750 
751 # The all: target is the default when no target is given on the
752 # command line.
753 # This allow a user to issue only 'make' to build a kernel including modules
754 # Defaults to vmlinux, but the arch makefile usually adds further targets
755 all: vmlinux
756 
757 CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage
758 ifdef CONFIG_CC_IS_GCC
759 CFLAGS_GCOV	+= -fno-tree-loop-im
760 endif
761 export CFLAGS_GCOV
762 
763 # The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
764 ifdef CONFIG_FUNCTION_TRACER
765   CC_FLAGS_FTRACE := -pg
766 endif
767 
768 include $(srctree)/arch/$(SRCARCH)/Makefile
769 
770 ifdef need-config
771 ifdef may-sync-config
772 # Read in dependencies to all Kconfig* files, make sure to run syncconfig if
773 # changes are detected. This should be included after arch/$(SRCARCH)/Makefile
774 # because some architectures define CROSS_COMPILE there.
775 include include/config/auto.conf.cmd
776 
777 $(KCONFIG_CONFIG):
778 	@echo >&2 '***'
779 	@echo >&2 '*** Configuration file "$@" not found!'
780 	@echo >&2 '***'
781 	@echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
782 	@echo >&2 '*** "make menuconfig" or "make xconfig").'
783 	@echo >&2 '***'
784 	@/bin/false
785 
786 # The actual configuration files used during the build are stored in
787 # include/generated/ and include/config/. Update them if .config is newer than
788 # include/config/auto.conf (which mirrors .config).
789 #
790 # This exploits the 'multi-target pattern rule' trick.
791 # The syncconfig should be executed only once to make all the targets.
792 # (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
793 #
794 # Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
795 # so you cannot notice that Kconfig is waiting for the user input.
796 %/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h %/generated/rustc_cfg: $(KCONFIG_CONFIG)
797 	$(Q)$(kecho) "  SYNC    $@"
798 	$(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
799 else # !may-sync-config
800 # External modules and some install targets need include/generated/autoconf.h
801 # and include/config/auto.conf but do not care if they are up-to-date.
802 # Use auto.conf to trigger the test
803 PHONY += include/config/auto.conf
804 
805 include/config/auto.conf:
806 	@test -e include/generated/autoconf.h -a -e $@ || (		\
807 	echo >&2;							\
808 	echo >&2 "  ERROR: Kernel configuration is invalid.";		\
809 	echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
810 	echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";	\
811 	echo >&2 ;							\
812 	/bin/false)
813 
814 endif # may-sync-config
815 endif # need-config
816 
817 KBUILD_CFLAGS	+= -fno-delete-null-pointer-checks
818 
819 ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
820 KBUILD_CFLAGS += -O2
821 KBUILD_RUSTFLAGS += -Copt-level=2
822 else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
823 KBUILD_CFLAGS += -Os
824 KBUILD_RUSTFLAGS += -Copt-level=s
825 endif
826 
827 # Always set `debug-assertions` and `overflow-checks` because their default
828 # depends on `opt-level` and `debug-assertions`, respectively.
829 KBUILD_RUSTFLAGS += -Cdebug-assertions=$(if $(CONFIG_RUST_DEBUG_ASSERTIONS),y,n)
830 KBUILD_RUSTFLAGS += -Coverflow-checks=$(if $(CONFIG_RUST_OVERFLOW_CHECKS),y,n)
831 
832 # Tell gcc to never replace conditional load with a non-conditional one
833 ifdef CONFIG_CC_IS_GCC
834 # gcc-10 renamed --param=allow-store-data-races=0 to
835 # -fno-allow-store-data-races.
836 KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
837 KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
838 endif
839 
840 ifdef CONFIG_READABLE_ASM
841 # Disable optimizations that make assembler listings hard to read.
842 # reorder blocks reorders the control in the function
843 # ipa clone creates specialized cloned functions
844 # partial inlining inlines only parts of functions
845 KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
846 endif
847 
848 stackp-flags-y                                    := -fno-stack-protector
849 stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
850 stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
851 
852 KBUILD_CFLAGS += $(stackp-flags-y)
853 
854 KBUILD_RUSTFLAGS-$(CONFIG_WERROR) += -Dwarnings
855 KBUILD_RUSTFLAGS += $(KBUILD_RUSTFLAGS-y)
856 
857 ifdef CONFIG_FRAME_POINTER
858 KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
859 KBUILD_RUSTFLAGS += -Cforce-frame-pointers=y
860 else
861 # Some targets (ARM with Thumb2, for example), can't be built with frame
862 # pointers.  For those, we don't have FUNCTION_TRACER automatically
863 # select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
864 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
865 # -fomit-frame-pointer with FUNCTION_TRACER.
866 # In the Rust target specification, "frame-pointer" is set explicitly
867 # to "may-omit".
868 ifndef CONFIG_FUNCTION_TRACER
869 KBUILD_CFLAGS	+= -fomit-frame-pointer
870 endif
871 endif
872 
873 # Initialize all stack variables with a 0xAA pattern.
874 ifdef CONFIG_INIT_STACK_ALL_PATTERN
875 KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
876 endif
877 
878 # Initialize all stack variables with a zero value.
879 ifdef CONFIG_INIT_STACK_ALL_ZERO
880 KBUILD_CFLAGS	+= -ftrivial-auto-var-init=zero
881 ifdef CONFIG_CC_HAS_AUTO_VAR_INIT_ZERO_ENABLER
882 # https://github.com/llvm/llvm-project/issues/44842
883 CC_AUTO_VAR_INIT_ZERO_ENABLER := -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
884 export CC_AUTO_VAR_INIT_ZERO_ENABLER
885 KBUILD_CFLAGS	+= $(CC_AUTO_VAR_INIT_ZERO_ENABLER)
886 endif
887 endif
888 
889 # While VLAs have been removed, GCC produces unreachable stack probes
890 # for the randomize_kstack_offset feature. Disable it for all compilers.
891 KBUILD_CFLAGS	+= $(call cc-option, -fno-stack-clash-protection)
892 
893 # Clear used registers at func exit (to reduce data lifetime and ROP gadgets).
894 ifdef CONFIG_ZERO_CALL_USED_REGS
895 KBUILD_CFLAGS	+= -fzero-call-used-regs=used-gpr
896 endif
897 
898 ifdef CONFIG_FUNCTION_TRACER
899 ifdef CONFIG_FTRACE_MCOUNT_USE_CC
900   CC_FLAGS_FTRACE	+= -mrecord-mcount
901   ifdef CONFIG_HAVE_NOP_MCOUNT
902     ifeq ($(call cc-option-yn, -mnop-mcount),y)
903       CC_FLAGS_FTRACE	+= -mnop-mcount
904       CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
905     endif
906   endif
907 endif
908 ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
909   ifdef CONFIG_HAVE_OBJTOOL_NOP_MCOUNT
910     CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
911   endif
912 endif
913 ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
914   ifdef CONFIG_HAVE_C_RECORDMCOUNT
915     BUILD_C_RECORDMCOUNT := y
916     export BUILD_C_RECORDMCOUNT
917   endif
918 endif
919 ifdef CONFIG_HAVE_FENTRY
920   # s390-linux-gnu-gcc did not support -mfentry until gcc-9.
921   ifeq ($(call cc-option-yn, -mfentry),y)
922     CC_FLAGS_FTRACE	+= -mfentry
923     CC_FLAGS_USING	+= -DCC_USING_FENTRY
924   endif
925 endif
926 export CC_FLAGS_FTRACE
927 KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
928 KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
929 endif
930 
931 # We trigger additional mismatches with less inlining
932 ifdef CONFIG_DEBUG_SECTION_MISMATCH
933 KBUILD_CFLAGS += -fno-inline-functions-called-once
934 endif
935 
936 # `rustc`'s `-Zfunction-sections` applies to data too (as of 1.59.0).
937 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
938 KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
939 KBUILD_RUSTFLAGS_KERNEL += -Zfunction-sections=y
940 LDFLAGS_vmlinux += --gc-sections
941 endif
942 
943 ifdef CONFIG_SHADOW_CALL_STACK
944 ifndef CONFIG_DYNAMIC_SCS
945 CC_FLAGS_SCS	:= -fsanitize=shadow-call-stack
946 KBUILD_CFLAGS	+= $(CC_FLAGS_SCS)
947 endif
948 export CC_FLAGS_SCS
949 endif
950 
951 ifdef CONFIG_LTO_CLANG
952 ifdef CONFIG_LTO_CLANG_THIN
953 CC_FLAGS_LTO	:= -flto=thin -fsplit-lto-unit
954 else
955 CC_FLAGS_LTO	:= -flto
956 endif
957 CC_FLAGS_LTO	+= -fvisibility=hidden
958 
959 # Limit inlining across translation units to reduce binary size
960 KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
961 
962 # Check for frame size exceeding threshold during prolog/epilog insertion
963 # when using lld < 13.0.0.
964 ifneq ($(CONFIG_FRAME_WARN),0)
965 ifeq ($(call test-lt, $(CONFIG_LLD_VERSION), 130000),y)
966 KBUILD_LDFLAGS	+= -plugin-opt=-warn-stack-size=$(CONFIG_FRAME_WARN)
967 endif
968 endif
969 endif
970 
971 ifdef CONFIG_LTO
972 KBUILD_CFLAGS	+= -fno-lto $(CC_FLAGS_LTO)
973 KBUILD_AFLAGS	+= -fno-lto
974 export CC_FLAGS_LTO
975 endif
976 
977 ifdef CONFIG_CFI_CLANG
978 CC_FLAGS_CFI	:= -fsanitize=kcfi
979 KBUILD_CFLAGS	+= $(CC_FLAGS_CFI)
980 export CC_FLAGS_CFI
981 endif
982 
983 ifneq ($(CONFIG_FUNCTION_ALIGNMENT),0)
984 KBUILD_CFLAGS += -falign-functions=$(CONFIG_FUNCTION_ALIGNMENT)
985 endif
986 
987 # arch Makefile may override CC so keep this after arch Makefile is included
988 NOSTDINC_FLAGS += -nostdinc
989 
990 # To gain proper coverage for CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE,
991 # the kernel uses only C99 flexible arrays for dynamically sized trailing
992 # arrays. Enforce this for everything that may examine structure sizes and
993 # perform bounds checking.
994 KBUILD_CFLAGS += $(call cc-option, -fstrict-flex-arrays=3)
995 
996 # disable invalid "can't wrap" optimizations for signed / pointers
997 KBUILD_CFLAGS	+= -fno-strict-overflow
998 
999 # Make sure -fstack-check isn't enabled (like gentoo apparently did)
1000 KBUILD_CFLAGS  += -fno-stack-check
1001 
1002 # conserve stack if available
1003 ifdef CONFIG_CC_IS_GCC
1004 KBUILD_CFLAGS   += -fconserve-stack
1005 endif
1006 
1007 # change __FILE__ to the relative path from the srctree
1008 KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
1009 
1010 # include additional Makefiles when needed
1011 include-y			:= scripts/Makefile.extrawarn
1012 include-$(CONFIG_DEBUG_INFO)	+= scripts/Makefile.debug
1013 include-$(CONFIG_KASAN)		+= scripts/Makefile.kasan
1014 include-$(CONFIG_KCSAN)		+= scripts/Makefile.kcsan
1015 include-$(CONFIG_KMSAN)		+= scripts/Makefile.kmsan
1016 include-$(CONFIG_UBSAN)		+= scripts/Makefile.ubsan
1017 include-$(CONFIG_KCOV)		+= scripts/Makefile.kcov
1018 include-$(CONFIG_RANDSTRUCT)	+= scripts/Makefile.randstruct
1019 include-$(CONFIG_GCC_PLUGINS)	+= scripts/Makefile.gcc-plugins
1020 
1021 include $(addprefix $(srctree)/, $(include-y))
1022 
1023 # scripts/Makefile.gcc-plugins is intentionally included last.
1024 # Do not add $(call cc-option,...) below this line. When you build the kernel
1025 # from the clean source tree, the GCC plugins do not exist at this point.
1026 
1027 # Add user supplied CPPFLAGS, AFLAGS, CFLAGS and RUSTFLAGS as the last assignments
1028 KBUILD_CPPFLAGS += $(KCPPFLAGS)
1029 KBUILD_AFLAGS   += $(KAFLAGS)
1030 KBUILD_CFLAGS   += $(KCFLAGS)
1031 KBUILD_RUSTFLAGS += $(KRUSTFLAGS)
1032 
1033 KBUILD_LDFLAGS_MODULE += --build-id=sha1
1034 LDFLAGS_vmlinux += --build-id=sha1
1035 
1036 KBUILD_LDFLAGS	+= -z noexecstack
1037 ifeq ($(CONFIG_LD_IS_BFD),y)
1038 KBUILD_LDFLAGS	+= $(call ld-option,--no-warn-rwx-segments)
1039 endif
1040 
1041 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1042 LDFLAGS_vmlinux	+= -X
1043 endif
1044 
1045 ifeq ($(CONFIG_RELR),y)
1046 # ld.lld before 15 did not support -z pack-relative-relocs.
1047 LDFLAGS_vmlinux	+= $(call ld-option,--pack-dyn-relocs=relr,-z pack-relative-relocs)
1048 endif
1049 
1050 # We never want expected sections to be placed heuristically by the
1051 # linker. All sections should be explicitly named in the linker script.
1052 ifdef CONFIG_LD_ORPHAN_WARN
1053 LDFLAGS_vmlinux += --orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL)
1054 endif
1055 
1056 # Align the bit size of userspace programs with the kernel
1057 KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1058 KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1059 
1060 # make the checker run with the right architecture
1061 CHECKFLAGS += --arch=$(ARCH)
1062 
1063 # insure the checker run with the right endianness
1064 CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1065 
1066 # the checker needs the correct machine size
1067 CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1068 
1069 # Default kernel image to build when no specific target is given.
1070 # KBUILD_IMAGE may be overruled on the command line or
1071 # set in the environment
1072 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
1073 # this default value
1074 export KBUILD_IMAGE ?= vmlinux
1075 
1076 #
1077 # INSTALL_PATH specifies where to place the updated kernel and system map
1078 # images. Default is /boot, but you can set it to other values
1079 export	INSTALL_PATH ?= /boot
1080 
1081 #
1082 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1083 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1084 # an argument if needed. Otherwise it defaults to the kernel install path
1085 #
1086 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1087 
1088 #
1089 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1090 # relocations required by build roots.  This is not defined in the
1091 # makefile but the argument can be passed to make if needed.
1092 #
1093 
1094 MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1095 export MODLIB
1096 
1097 PHONY += prepare0
1098 
1099 export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
1100 export MODORDER := $(extmod_prefix)modules.order
1101 export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
1102 
1103 ifeq ($(KBUILD_EXTMOD),)
1104 
1105 build-dir	:= .
1106 clean-dirs	:= $(sort . Documentation \
1107 		     $(patsubst %/,%,$(filter %/, $(core-) \
1108 			$(drivers-) $(libs-))))
1109 
1110 export ARCH_CORE	:= $(core-y)
1111 export ARCH_LIB		:= $(filter %/, $(libs-y))
1112 export ARCH_DRIVERS	:= $(drivers-y) $(drivers-m)
1113 # Externally visible symbols (used by link-vmlinux.sh)
1114 
1115 KBUILD_VMLINUX_OBJS := ./built-in.a
1116 ifdef CONFIG_MODULES
1117 KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1118 KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1119 else
1120 KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1121 endif
1122 
1123 export KBUILD_VMLINUX_LIBS
1124 export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1125 
1126 ifdef CONFIG_TRIM_UNUSED_KSYMS
1127 # For the kernel to actually contain only the needed exported symbols,
1128 # we have to build modules as well to determine what those symbols are.
1129 KBUILD_MODULES := 1
1130 endif
1131 
1132 # '$(AR) mPi' needs 'T' to workaround the bug of llvm-ar <= 14
1133 quiet_cmd_ar_vmlinux.a = AR      $@
1134       cmd_ar_vmlinux.a = \
1135 	rm -f $@; \
1136 	$(AR) cDPrST $@ $(KBUILD_VMLINUX_OBJS); \
1137 	$(AR) mPiT $$($(AR) t $@ | sed -n 1p) $@ $$($(AR) t $@ | grep -F -f $(srctree)/scripts/head-object-list.txt)
1138 
1139 targets += vmlinux.a
1140 vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt FORCE
1141 	$(call if_changed,ar_vmlinux.a)
1142 
1143 PHONY += vmlinux_o
1144 vmlinux_o: vmlinux.a $(KBUILD_VMLINUX_LIBS)
1145 	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o
1146 
1147 vmlinux.o modules.builtin.modinfo modules.builtin: vmlinux_o
1148 	@:
1149 
1150 PHONY += vmlinux
1151 # LDFLAGS_vmlinux in the top Makefile defines linker flags for the top vmlinux,
1152 # not for decompressors. LDFLAGS_vmlinux in arch/*/boot/compressed/Makefile is
1153 # unrelated; the decompressors just happen to have the same base name,
1154 # arch/*/boot/compressed/vmlinux.
1155 # Export LDFLAGS_vmlinux only to scripts/Makefile.vmlinux.
1156 #
1157 # _LDFLAGS_vmlinux is a workaround for the 'private export' bug:
1158 #   https://savannah.gnu.org/bugs/?61463
1159 # For Make > 4.4, the following simple code will work:
1160 #  vmlinux: private export LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1161 vmlinux: private _LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1162 vmlinux: export LDFLAGS_vmlinux = $(_LDFLAGS_vmlinux)
1163 vmlinux: vmlinux.o $(KBUILD_LDS) modpost
1164 	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux
1165 
1166 # The actual objects are generated when descending,
1167 # make sure no implicit rule kicks in
1168 $(sort $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)): . ;
1169 
1170 ifeq ($(origin KERNELRELEASE),file)
1171 filechk_kernel.release = $(srctree)/scripts/setlocalversion $(srctree)
1172 else
1173 filechk_kernel.release = echo $(KERNELRELEASE)
1174 endif
1175 
1176 # Store (new) KERNELRELEASE string in include/config/kernel.release
1177 include/config/kernel.release: FORCE
1178 	$(call filechk,kernel.release)
1179 
1180 # Additional helpers built in scripts/
1181 # Carefully list dependencies so we do not try to build scripts twice
1182 # in parallel
1183 PHONY += scripts
1184 scripts: scripts_basic scripts_dtc
1185 	$(Q)$(MAKE) $(build)=$(@)
1186 
1187 # Things we need to do before we recursively start building the kernel
1188 # or the modules are listed in "prepare".
1189 # A multi level approach is used. prepareN is processed before prepareN-1.
1190 # archprepare is used in arch Makefiles and when processed asm symlink,
1191 # version.h and scripts_basic is processed / created.
1192 
1193 PHONY += prepare archprepare
1194 
1195 archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1196 	asm-generic $(version_h) include/generated/utsrelease.h \
1197 	include/generated/compile.h include/generated/autoconf.h remove-stale-files
1198 
1199 prepare0: archprepare
1200 	$(Q)$(MAKE) $(build)=scripts/mod
1201 	$(Q)$(MAKE) $(build)=. prepare
1202 
1203 # All the preparing..
1204 prepare: prepare0
1205 ifdef CONFIG_RUST
1206 	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh
1207 	$(Q)$(MAKE) $(build)=rust
1208 endif
1209 
1210 PHONY += remove-stale-files
1211 remove-stale-files:
1212 	$(Q)$(srctree)/scripts/remove-stale-files
1213 
1214 # Support for using generic headers in asm-generic
1215 asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1216 
1217 PHONY += asm-generic uapi-asm-generic
1218 asm-generic: uapi-asm-generic
1219 	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1220 	generic=include/asm-generic
1221 uapi-asm-generic:
1222 	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1223 	generic=include/uapi/asm-generic
1224 
1225 # Generate some files
1226 # ---------------------------------------------------------------------------
1227 
1228 # KERNELRELEASE can change from a few different places, meaning version.h
1229 # needs to be updated, so this check is forced on all builds
1230 
1231 uts_len := 64
1232 define filechk_utsrelease.h
1233 	if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1234 	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1235 	  exit 1;                                                         \
1236 	fi;                                                               \
1237 	echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1238 endef
1239 
1240 define filechk_version.h
1241 	if [ $(SUBLEVEL) -gt 255 ]; then                                 \
1242 		echo \#define LINUX_VERSION_CODE $(shell                 \
1243 		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1244 	else                                                             \
1245 		echo \#define LINUX_VERSION_CODE $(shell                 \
1246 		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1247 	fi;                                                              \
1248 	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
1249 	((c) > 255 ? 255 : (c)))';                                       \
1250 	echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
1251 	echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
1252 	echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1253 endef
1254 
1255 $(version_h): PATCHLEVEL := $(or $(PATCHLEVEL), 0)
1256 $(version_h): SUBLEVEL := $(or $(SUBLEVEL), 0)
1257 $(version_h): FORCE
1258 	$(call filechk,version.h)
1259 
1260 include/generated/utsrelease.h: include/config/kernel.release FORCE
1261 	$(call filechk,utsrelease.h)
1262 
1263 filechk_compile.h = $(srctree)/scripts/mkcompile_h \
1264 	"$(UTS_MACHINE)" "$(CONFIG_CC_VERSION_TEXT)" "$(LD)"
1265 
1266 include/generated/compile.h: FORCE
1267 	$(call filechk,compile.h)
1268 
1269 PHONY += headerdep
1270 headerdep:
1271 	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1272 	$(srctree)/scripts/headerdep.pl -I$(srctree)/include
1273 
1274 # ---------------------------------------------------------------------------
1275 # Kernel headers
1276 
1277 #Default location for installed headers
1278 export INSTALL_HDR_PATH = $(objtree)/usr
1279 
1280 quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1281       cmd_headers_install = \
1282 	mkdir -p $(INSTALL_HDR_PATH); \
1283 	rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1284 	usr/include $(INSTALL_HDR_PATH)
1285 
1286 PHONY += headers_install
1287 headers_install: headers
1288 	$(call cmd,headers_install)
1289 
1290 PHONY += archheaders archscripts
1291 
1292 hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1293 
1294 PHONY += headers
1295 headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1296 	$(if $(filter um, $(SRCARCH)), $(error Headers not exportable for UML))
1297 	$(Q)$(MAKE) $(hdr-inst)=include/uapi
1298 	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1299 
1300 ifdef CONFIG_HEADERS_INSTALL
1301 prepare: headers
1302 endif
1303 
1304 PHONY += scripts_unifdef
1305 scripts_unifdef: scripts_basic
1306 	$(Q)$(MAKE) $(build)=scripts scripts/unifdef
1307 
1308 # ---------------------------------------------------------------------------
1309 # Install
1310 
1311 # Many distributions have the custom install script, /sbin/installkernel.
1312 # If DKMS is installed, 'make install' will eventually recurse back
1313 # to this Makefile to build and install external modules.
1314 # Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
1315 
1316 quiet_cmd_install = INSTALL $(INSTALL_PATH)
1317       cmd_install = unset sub_make_done; $(srctree)/scripts/install.sh
1318 
1319 # ---------------------------------------------------------------------------
1320 # vDSO install
1321 
1322 PHONY += vdso_install
1323 vdso_install: export INSTALL_FILES = $(vdso-install-y)
1324 vdso_install:
1325 	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vdsoinst
1326 
1327 # ---------------------------------------------------------------------------
1328 # Tools
1329 
1330 ifdef CONFIG_OBJTOOL
1331 prepare: tools/objtool
1332 endif
1333 
1334 ifdef CONFIG_BPF
1335 ifdef CONFIG_DEBUG_INFO_BTF
1336 prepare: tools/bpf/resolve_btfids
1337 endif
1338 endif
1339 
1340 PHONY += resolve_btfids_clean
1341 
1342 resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1343 
1344 # tools/bpf/resolve_btfids directory might not exist
1345 # in output directory, skip its clean in that case
1346 resolve_btfids_clean:
1347 ifneq ($(wildcard $(resolve_btfids_O)),)
1348 	$(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1349 endif
1350 
1351 # Clear a bunch of variables before executing the submake
1352 ifeq ($(quiet),silent_)
1353 tools_silent=s
1354 endif
1355 
1356 tools/: FORCE
1357 	$(Q)mkdir -p $(objtree)/tools
1358 	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1359 
1360 tools/%: FORCE
1361 	$(Q)mkdir -p $(objtree)/tools
1362 	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1363 
1364 # ---------------------------------------------------------------------------
1365 # Kernel selftest
1366 
1367 PHONY += kselftest
1368 kselftest: headers
1369 	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1370 
1371 kselftest-%: headers FORCE
1372 	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1373 
1374 PHONY += kselftest-merge
1375 kselftest-merge:
1376 	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1377 	$(Q)find $(srctree)/tools/testing/selftests -name config | \
1378 		xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1379 	$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1380 
1381 # ---------------------------------------------------------------------------
1382 # Devicetree files
1383 
1384 ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1385 dtstree := arch/$(SRCARCH)/boot/dts
1386 endif
1387 
1388 ifneq ($(dtstree),)
1389 
1390 %.dtb: dtbs_prepare
1391 	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1392 
1393 %.dtbo: dtbs_prepare
1394 	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1395 
1396 PHONY += dtbs dtbs_prepare dtbs_install dtbs_check
1397 dtbs: dtbs_prepare
1398 	$(Q)$(MAKE) $(build)=$(dtstree)
1399 
1400 # include/config/kernel.release is actually needed when installing DTBs because
1401 # INSTALL_DTBS_PATH contains $(KERNELRELEASE). However, we do not want to make
1402 # dtbs_install depend on it as dtbs_install may run as root.
1403 dtbs_prepare: include/config/kernel.release scripts_dtc
1404 
1405 ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1406 export CHECK_DTBS=y
1407 endif
1408 
1409 ifneq ($(CHECK_DTBS),)
1410 dtbs_prepare: dt_binding_check
1411 endif
1412 
1413 dtbs_check: dtbs
1414 
1415 dtbs_install:
1416 	$(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1417 
1418 ifdef CONFIG_OF_EARLY_FLATTREE
1419 all: dtbs
1420 endif
1421 
1422 endif
1423 
1424 PHONY += scripts_dtc
1425 scripts_dtc: scripts_basic
1426 	$(Q)$(MAKE) $(build)=scripts/dtc
1427 
1428 ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1429 export CHECK_DT_BINDING=y
1430 endif
1431 
1432 PHONY += dt_binding_check
1433 dt_binding_check: scripts_dtc
1434 	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1435 
1436 PHONY += dt_compatible_check
1437 dt_compatible_check: dt_binding_check
1438 	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1439 
1440 # ---------------------------------------------------------------------------
1441 # Modules
1442 
1443 ifdef CONFIG_MODULES
1444 
1445 # By default, build modules as well
1446 
1447 all: modules
1448 
1449 # When we're building modules with modversions, we need to consider
1450 # the built-in objects during the descend as well, in order to
1451 # make sure the checksums are up to date before we record them.
1452 ifdef CONFIG_MODVERSIONS
1453   KBUILD_BUILTIN := 1
1454 endif
1455 
1456 # Build modules
1457 #
1458 
1459 # *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFO_BTF_MODULES
1460 # is an exception.
1461 ifdef CONFIG_DEBUG_INFO_BTF_MODULES
1462 KBUILD_BUILTIN := 1
1463 modules: vmlinux
1464 endif
1465 
1466 modules: modules_prepare
1467 
1468 # Target to prepare building external modules
1469 modules_prepare: prepare
1470 	$(Q)$(MAKE) $(build)=scripts scripts/module.lds
1471 
1472 endif # CONFIG_MODULES
1473 
1474 ###
1475 # Cleaning is done on three levels.
1476 # make clean     Delete most generated files
1477 #                Leave enough to build external modules
1478 # make mrproper  Delete the current configuration, and all generated files
1479 # make distclean Remove editor backup files, patch leftover files and the like
1480 
1481 # Directories & files removed with 'make clean'
1482 CLEAN_FILES += vmlinux.symvers modules-only.symvers \
1483 	       modules.builtin modules.builtin.modinfo modules.nsdeps \
1484 	       compile_commands.json rust/test \
1485 	       rust-project.json .vmlinux.objs .vmlinux.export.c
1486 
1487 # Directories & files removed with 'make mrproper'
1488 MRPROPER_FILES += include/config include/generated          \
1489 		  arch/$(SRCARCH)/include/generated .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 		  kernel.spec rpmbuild \
1497 		  rust/libmacros.so
1498 
1499 # clean - Delete most, but leave enough to build external modules
1500 #
1501 clean: rm-files := $(CLEAN_FILES)
1502 
1503 PHONY += archclean vmlinuxclean
1504 
1505 vmlinuxclean:
1506 	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1507 	$(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1508 
1509 clean: archclean vmlinuxclean resolve_btfids_clean
1510 
1511 # mrproper - Delete all generated files, including .config
1512 #
1513 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1514 mrproper-dirs      := $(addprefix _mrproper_,scripts)
1515 
1516 PHONY += $(mrproper-dirs) mrproper
1517 $(mrproper-dirs):
1518 	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1519 
1520 mrproper: clean $(mrproper-dirs)
1521 	$(call cmd,rmfiles)
1522 	@find . $(RCS_FIND_IGNORE) \
1523 		\( -name '*.rmeta' \) \
1524 		-type f -print | xargs rm -f
1525 
1526 # distclean
1527 #
1528 PHONY += distclean
1529 
1530 distclean: mrproper
1531 	@find . $(RCS_FIND_IGNORE) \
1532 		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1533 		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
1534 		-o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1535 		-o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1536 		-type f -print | xargs rm -f
1537 
1538 
1539 # Packaging of the kernel to various formats
1540 # ---------------------------------------------------------------------------
1541 
1542 %src-pkg: FORCE
1543 	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1544 %pkg: include/config/kernel.release FORCE
1545 	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1546 
1547 # Brief documentation of the typical targets used
1548 # ---------------------------------------------------------------------------
1549 
1550 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1551 boards := $(sort $(notdir $(boards)))
1552 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1553 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1554 
1555 PHONY += help
1556 help:
1557 	@echo  'Cleaning targets:'
1558 	@echo  '  clean		  - Remove most generated files but keep the config and'
1559 	@echo  '                    enough build support to build external modules'
1560 	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
1561 	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
1562 	@echo  ''
1563 	@$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1564 	@echo  ''
1565 	@echo  'Other generic targets:'
1566 	@echo  '  all		  - Build all targets marked with [*]'
1567 	@echo  '* vmlinux	  - Build the bare kernel'
1568 	@echo  '* modules	  - Build all modules'
1569 	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1570 	@echo  '  vdso_install    - Install unstripped vdso to INSTALL_MOD_PATH (default: /)'
1571 	@echo  '  dir/            - Build all files in dir and below'
1572 	@echo  '  dir/file.[ois]  - Build specified target only'
1573 	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1574 	@echo  '                    (requires compiler support for LLVM assembly generation)'
1575 	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1576 	@echo  '                    (requires a recent binutils and recent build (System.map))'
1577 	@echo  '  dir/file.ko     - Build module including final link'
1578 	@echo  '  modules_prepare - Set up for building external modules'
1579 	@echo  '  tags/TAGS	  - Generate tags file for editors'
1580 	@echo  '  cscope	  - Generate cscope index'
1581 	@echo  '  gtags           - Generate GNU GLOBAL index'
1582 	@echo  '  kernelrelease	  - Output the release version string (use with make -s)'
1583 	@echo  '  kernelversion	  - Output the version stored in Makefile (use with make -s)'
1584 	@echo  '  image_name	  - Output the image name (use with make -s)'
1585 	@echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1586 	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1587 	 echo  ''
1588 	@echo  'Static analysers:'
1589 	@echo  '  checkstack      - Generate a list of stack hogs'
1590 	@echo  '  versioncheck    - Sanity check on version.h usage'
1591 	@echo  '  includecheck    - Check for duplicate included header files'
1592 	@echo  '  export_report   - List the usages of all exported symbols'
1593 	@echo  '  headerdep       - Detect inclusion cycles in headers'
1594 	@echo  '  coccicheck      - Check with Coccinelle'
1595 	@echo  '  clang-analyzer  - Check with clang static analyzer'
1596 	@echo  '  clang-tidy      - Check with clang-tidy'
1597 	@echo  ''
1598 	@echo  'Tools:'
1599 	@echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1600 	@echo  ''
1601 	@echo  'Kernel selftest:'
1602 	@echo  '  kselftest         - Build and run kernel selftest'
1603 	@echo  '                      Build, install, and boot kernel before'
1604 	@echo  '                      running kselftest on it'
1605 	@echo  '                      Run as root for full coverage'
1606 	@echo  '  kselftest-all     - Build kernel selftest'
1607 	@echo  '  kselftest-install - Build and install kernel selftest'
1608 	@echo  '  kselftest-clean   - Remove all generated kselftest files'
1609 	@echo  '  kselftest-merge   - Merge all the config dependencies of'
1610 	@echo  '		      kselftest to existing .config.'
1611 	@echo  ''
1612 	@echo  'Rust targets:'
1613 	@echo  '  rustavailable   - Checks whether the Rust toolchain is'
1614 	@echo  '		    available and, if not, explains why.'
1615 	@echo  '  rustfmt	  - Reformat all the Rust code in the kernel'
1616 	@echo  '  rustfmtcheck	  - Checks if all the Rust code in the kernel'
1617 	@echo  '		    is formatted, printing a diff otherwise.'
1618 	@echo  '  rustdoc	  - Generate Rust documentation'
1619 	@echo  '		    (requires kernel .config)'
1620 	@echo  '  rusttest        - Runs the Rust tests'
1621 	@echo  '                    (requires kernel .config; downloads external repos)'
1622 	@echo  '  rust-analyzer	  - Generate rust-project.json rust-analyzer support file'
1623 	@echo  '		    (requires kernel .config)'
1624 	@echo  '  dir/file.[os]   - Build specified target only'
1625 	@echo  '  dir/file.rsi    - Build macro expanded source, similar to C preprocessing.'
1626 	@echo  '                    Run with RUSTFMT=n to skip reformatting if needed.'
1627 	@echo  '                    The output is not intended to be compilable.'
1628 	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1629 	@echo  ''
1630 	@$(if $(dtstree), \
1631 		echo 'Devicetree:'; \
1632 		echo '* dtbs             - Build device tree blobs for enabled boards'; \
1633 		echo '  dtbs_install     - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1634 		echo '  dt_binding_check - Validate device tree binding documents'; \
1635 		echo '  dtbs_check       - Validate device tree source files';\
1636 		echo '')
1637 
1638 	@echo 'Userspace tools targets:'
1639 	@echo '  use "make tools/help"'
1640 	@echo '  or  "cd tools; make help"'
1641 	@echo  ''
1642 	@echo  'Kernel packaging:'
1643 	@$(MAKE) -f $(srctree)/scripts/Makefile.package help
1644 	@echo  ''
1645 	@echo  'Documentation targets:'
1646 	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1647 	@echo  ''
1648 	@echo  'Architecture specific targets ($(SRCARCH)):'
1649 	@$(or $(archhelp),\
1650 		echo '  No architecture specific help defined for $(SRCARCH)')
1651 	@echo  ''
1652 	@$(if $(boards), \
1653 		$(foreach b, $(boards), \
1654 		printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1655 		echo '')
1656 	@$(if $(board-dirs), \
1657 		$(foreach b, $(board-dirs), \
1658 		printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1659 		printf "  %-16s - Show all of the above\\n" help-boards; \
1660 		echo '')
1661 
1662 	@echo  '  make V=n   [targets] 1: verbose build'
1663 	@echo  '                       2: give reason for rebuild of target'
1664 	@echo  '                       V=1 and V=2 can be combined with V=12'
1665 	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1666 	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1667 	@echo  '                       (sparse by default)'
1668 	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1669 	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1670 	@echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
1671 	@echo  '		1: warnings which may be relevant and do not occur too often'
1672 	@echo  '		2: warnings which occur quite often but may still be relevant'
1673 	@echo  '		3: more obscure warnings, can most likely be ignored'
1674 	@echo  '		e: warnings are being treated as errors'
1675 	@echo  '		Multiple levels can be combined with W=12 or W=123'
1676 	@$(if $(dtstree), \
1677 		echo '  make CHECK_DTBS=1 [targets] Check all generated dtb files against schema'; \
1678 		echo '         This can be applied both to "dtbs" and to individual "foo.dtb" targets' ; \
1679 		)
1680 	@echo  ''
1681 	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
1682 	@echo  'For further info see the ./README file'
1683 
1684 
1685 help-board-dirs := $(addprefix help-,$(board-dirs))
1686 
1687 help-boards: $(help-board-dirs)
1688 
1689 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1690 
1691 $(help-board-dirs): help-%:
1692 	@echo  'Architecture specific targets ($(SRCARCH) $*):'
1693 	@$(if $(boards-per-dir), \
1694 		$(foreach b, $(boards-per-dir), \
1695 		printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1696 		echo '')
1697 
1698 
1699 # Documentation targets
1700 # ---------------------------------------------------------------------------
1701 DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1702 	       linkcheckdocs dochelp refcheckdocs texinfodocs infodocs
1703 PHONY += $(DOC_TARGETS)
1704 $(DOC_TARGETS):
1705 	$(Q)$(MAKE) $(build)=Documentation $@
1706 
1707 
1708 # Rust targets
1709 # ---------------------------------------------------------------------------
1710 
1711 # "Is Rust available?" target
1712 PHONY += rustavailable
1713 rustavailable:
1714 	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh && echo "Rust is available!"
1715 
1716 # Documentation target
1717 #
1718 # Using the singular to avoid running afoul of `no-dot-config-targets`.
1719 PHONY += rustdoc
1720 rustdoc: prepare
1721 	$(Q)$(MAKE) $(build)=rust $@
1722 
1723 # Testing target
1724 PHONY += rusttest
1725 rusttest: prepare
1726 	$(Q)$(MAKE) $(build)=rust $@
1727 
1728 # Formatting targets
1729 PHONY += rustfmt rustfmtcheck
1730 
1731 # We skip `rust/alloc` since we want to minimize the diff w.r.t. upstream.
1732 #
1733 # We match using absolute paths since `find` does not resolve them
1734 # when matching, which is a problem when e.g. `srctree` is `..`.
1735 # We `grep` afterwards in order to remove the directory entry itself.
1736 rustfmt:
1737 	$(Q)find $(abs_srctree) -type f -name '*.rs' \
1738 		-o -path $(abs_srctree)/rust/alloc -prune \
1739 		-o -path $(abs_objtree)/rust/test -prune \
1740 		| grep -Fv $(abs_srctree)/rust/alloc \
1741 		| grep -Fv $(abs_objtree)/rust/test \
1742 		| grep -Fv generated \
1743 		| xargs $(RUSTFMT) $(rustfmt_flags)
1744 
1745 rustfmtcheck: rustfmt_flags = --check
1746 rustfmtcheck: rustfmt
1747 
1748 # Misc
1749 # ---------------------------------------------------------------------------
1750 
1751 PHONY += misc-check
1752 misc-check:
1753 	$(Q)$(srctree)/scripts/misc-check
1754 
1755 all: misc-check
1756 
1757 PHONY += scripts_gdb
1758 scripts_gdb: prepare0
1759 	$(Q)$(MAKE) $(build)=scripts/gdb
1760 	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1761 
1762 ifdef CONFIG_GDB_SCRIPTS
1763 all: scripts_gdb
1764 endif
1765 
1766 else # KBUILD_EXTMOD
1767 
1768 filechk_kernel.release = echo $(KERNELRELEASE)
1769 
1770 ###
1771 # External module support.
1772 # When building external modules the kernel used as basis is considered
1773 # read-only, and no consistency checks are made and the make
1774 # system is not used on the basis kernel. If updates are required
1775 # in the basis kernel ordinary make commands (without M=...) must be used.
1776 
1777 # We are always building only modules.
1778 KBUILD_BUILTIN :=
1779 KBUILD_MODULES := 1
1780 
1781 build-dir := $(KBUILD_EXTMOD)
1782 
1783 compile_commands.json: $(extmod_prefix)compile_commands.json
1784 PHONY += compile_commands.json
1785 
1786 clean-dirs := $(KBUILD_EXTMOD)
1787 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1788 	$(KBUILD_EXTMOD)/compile_commands.json
1789 
1790 PHONY += prepare
1791 # now expand this into a simple variable to reduce the cost of shell evaluations
1792 prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT)
1793 prepare:
1794 	@if [ "$(CC_VERSION_TEXT)" != "$(CONFIG_CC_VERSION_TEXT)" ]; then \
1795 		echo >&2 "warning: the compiler differs from the one used to build the kernel"; \
1796 		echo >&2 "  The kernel was built by: $(CONFIG_CC_VERSION_TEXT)"; \
1797 		echo >&2 "  You are using:           $(CC_VERSION_TEXT)"; \
1798 	fi
1799 
1800 PHONY += help
1801 help:
1802 	@echo  '  Building external modules.'
1803 	@echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1804 	@echo  ''
1805 	@echo  '  modules         - default target, build the module(s)'
1806 	@echo  '  modules_install - install the module'
1807 	@echo  '  clean           - remove generated files in module directory only'
1808 	@echo  '  rust-analyzer	  - generate rust-project.json rust-analyzer support file'
1809 	@echo  ''
1810 
1811 ifndef CONFIG_MODULES
1812 modules modules_install: __external_modules_error
1813 __external_modules_error:
1814 	@echo >&2 '***'
1815 	@echo >&2 '*** The present kernel disabled CONFIG_MODULES.'
1816 	@echo >&2 '*** You cannot build or install external modules.'
1817 	@echo >&2 '***'
1818 	@false
1819 endif
1820 
1821 endif # KBUILD_EXTMOD
1822 
1823 # ---------------------------------------------------------------------------
1824 # Modules
1825 
1826 PHONY += modules modules_install modules_sign modules_prepare
1827 
1828 modules_install:
1829 	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst \
1830 	sign-only=$(if $(filter modules_install,$(MAKECMDGOALS)),,y)
1831 
1832 ifeq ($(CONFIG_MODULE_SIG),y)
1833 # modules_sign is a subset of modules_install.
1834 # 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1835 modules_sign: modules_install
1836 	@:
1837 else
1838 modules_sign:
1839 	@echo >&2 '***'
1840 	@echo >&2 '*** CONFIG_MODULE_SIG is disabled. You cannot sign modules.'
1841 	@echo >&2 '***'
1842 	@false
1843 endif
1844 
1845 ifdef CONFIG_MODULES
1846 
1847 $(MODORDER): $(build-dir)
1848 	@:
1849 
1850 # KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
1851 # This is solely useful to speed up test compiles.
1852 modules: modpost
1853 ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1854 	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1855 endif
1856 
1857 PHONY += modules_check
1858 modules_check: $(MODORDER)
1859 	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1860 
1861 else # CONFIG_MODULES
1862 
1863 modules:
1864 	@:
1865 
1866 KBUILD_MODULES :=
1867 
1868 endif # CONFIG_MODULES
1869 
1870 PHONY += modpost
1871 modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \
1872 	 $(if $(KBUILD_MODULES), modules_check)
1873 	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1874 
1875 # Single targets
1876 # ---------------------------------------------------------------------------
1877 # To build individual files in subdirectories, you can do like this:
1878 #
1879 #   make foo/bar/baz.s
1880 #
1881 # The supported suffixes for single-target are listed in 'single-targets'
1882 #
1883 # To build only under specific subdirectories, you can do like this:
1884 #
1885 #   make foo/bar/baz/
1886 
1887 ifdef single-build
1888 
1889 # .ko is special because modpost is needed
1890 single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1891 single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \
1892 		$(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko)))
1893 
1894 $(single-ko): single_modules
1895 	@:
1896 $(single-no-ko): $(build-dir)
1897 	@:
1898 
1899 # Remove MODORDER when done because it is not the real one.
1900 PHONY += single_modules
1901 single_modules: $(single-no-ko) modules_prepare
1902 	$(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$(m:%.ko=%.o);) } > $(MODORDER)
1903 	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1904 ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1905 	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1906 endif
1907 	$(Q)rm -f $(MODORDER)
1908 
1909 single-goals := $(addprefix $(build-dir)/, $(single-no-ko))
1910 
1911 KBUILD_MODULES := 1
1912 
1913 endif
1914 
1915 # Preset locale variables to speed up the build process. Limit locale
1916 # tweaks to this spot to avoid wrong language settings when running
1917 # make menuconfig etc.
1918 # Error messages still appears in the original language
1919 PHONY += $(build-dir)
1920 $(build-dir): prepare
1921 	$(Q)$(MAKE) $(build)=$@ need-builtin=1 need-modorder=1 $(single-goals)
1922 
1923 clean-dirs := $(addprefix _clean_, $(clean-dirs))
1924 PHONY += $(clean-dirs) clean
1925 $(clean-dirs):
1926 	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1927 
1928 clean: $(clean-dirs)
1929 	$(call cmd,rmfiles)
1930 	@find $(or $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1931 		\( -name '*.[aios]' -o -name '*.rsi' -o -name '*.ko' -o -name '.*.cmd' \
1932 		-o -name '*.ko.*' \
1933 		-o -name '*.dtb' -o -name '*.dtbo' \
1934 		-o -name '*.dtb.S' -o -name '*.dtbo.S' \
1935 		-o -name '*.dt.yaml' \
1936 		-o -name '*.dwo' -o -name '*.lst' \
1937 		-o -name '*.su' -o -name '*.mod' \
1938 		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1939 		-o -name '*.lex.c' -o -name '*.tab.[ch]' \
1940 		-o -name '*.asn1.[ch]' \
1941 		-o -name '*.symtypes' -o -name 'modules.order' \
1942 		-o -name '*.c.[012]*.*' \
1943 		-o -name '*.ll' \
1944 		-o -name '*.gcno' \
1945 		-o -name '*.*.symversions' \) -type f -print \
1946 		-o -name '.tmp_*' -print \
1947 		| xargs rm -rf
1948 
1949 # Generate tags for editors
1950 # ---------------------------------------------------------------------------
1951 quiet_cmd_tags = GEN     $@
1952       cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1953 
1954 tags TAGS cscope gtags: FORCE
1955 	$(call cmd,tags)
1956 
1957 # IDE support targets
1958 PHONY += rust-analyzer
1959 rust-analyzer:
1960 	$(Q)$(MAKE) $(build)=rust $@
1961 
1962 # Script to generate missing namespace dependencies
1963 # ---------------------------------------------------------------------------
1964 
1965 PHONY += nsdeps
1966 nsdeps: export KBUILD_NSDEPS=1
1967 nsdeps: modules
1968 	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1969 
1970 # Clang Tooling
1971 # ---------------------------------------------------------------------------
1972 
1973 quiet_cmd_gen_compile_commands = GEN     $@
1974       cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
1975 
1976 $(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
1977 	$(if $(KBUILD_EXTMOD),, vmlinux.a $(KBUILD_VMLINUX_LIBS)) \
1978 	$(if $(CONFIG_MODULES), $(MODORDER)) FORCE
1979 	$(call if_changed,gen_compile_commands)
1980 
1981 targets += $(extmod_prefix)compile_commands.json
1982 
1983 PHONY += clang-tidy clang-analyzer
1984 
1985 ifdef CONFIG_CC_IS_CLANG
1986 quiet_cmd_clang_tools = CHECK   $<
1987       cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
1988 
1989 clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
1990 	$(call cmd,clang_tools)
1991 else
1992 clang-tidy clang-analyzer:
1993 	@echo "$@ requires CC=clang" >&2
1994 	@false
1995 endif
1996 
1997 # Scripts to check various things for consistency
1998 # ---------------------------------------------------------------------------
1999 
2000 PHONY += includecheck versioncheck coccicheck export_report
2001 
2002 includecheck:
2003 	find $(srctree)/* $(RCS_FIND_IGNORE) \
2004 		-name '*.[hcS]' -type f -print | sort \
2005 		| xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
2006 
2007 versioncheck:
2008 	find $(srctree)/* $(RCS_FIND_IGNORE) \
2009 		-name '*.[hcS]' -type f -print | sort \
2010 		| xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
2011 
2012 coccicheck:
2013 	$(Q)$(BASH) $(srctree)/scripts/$@
2014 
2015 export_report:
2016 	$(PERL) $(srctree)/scripts/export_report.pl
2017 
2018 PHONY += checkstack kernelrelease kernelversion image_name
2019 
2020 # UML needs a little special treatment here.  It wants to use the host
2021 # toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
2022 # else wants $(ARCH), including people doing cross-builds, which means
2023 # that $(SUBARCH) doesn't work here.
2024 ifeq ($(ARCH), um)
2025 CHECKSTACK_ARCH := $(SUBARCH)
2026 else
2027 CHECKSTACK_ARCH := $(ARCH)
2028 endif
2029 checkstack:
2030 	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
2031 	$(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
2032 
2033 kernelrelease:
2034 	@$(filechk_kernel.release)
2035 
2036 kernelversion:
2037 	@echo $(KERNELVERSION)
2038 
2039 image_name:
2040 	@echo $(KBUILD_IMAGE)
2041 
2042 PHONY += run-command
2043 run-command:
2044 	$(Q)$(KBUILD_RUN_COMMAND)
2045 
2046 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
2047       cmd_rmfiles = rm -rf $(rm-files)
2048 
2049 # read saved command lines for existing targets
2050 existing-targets := $(wildcard $(sort $(targets)))
2051 
2052 -include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
2053 
2054 endif # config-build
2055 endif # mixed-build
2056 endif # need-sub-make
2057 
2058 PHONY += FORCE
2059 FORCE:
2060 
2061 # Declare the contents of the PHONY variable as phony.  We keep that
2062 # information in a variable so we can use it in if_changed and friends.
2063 .PHONY: $(PHONY)
2064