module: Convert symbol namespace to string literal
[linux.git] / Makefile
blob93ab62cef244ff99701e271bd23ef18c5b6b30ba
1 # SPDX-License-Identifier: GPL-2.0
2 VERSION = 6
3 PATCHLEVEL = 13
4 SUBLEVEL = 0
5 EXTRAVERSION = -rc1
6 NAME = Baby Opossum Posse
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.
14 ifeq ($(filter output-sync,$(.FEATURES)),)
15 $(error GNU Make >= 4.0 is required. Your Make version is $(MAKE_VERSION))
16 endif
18 $(if $(filter __%, $(MAKECMDGOALS)), \
19 $(error targets prefixed with '__' are only for internal use))
21 # That's our default target when none is given on the command line
22 PHONY := __all
23 __all:
25 # We are using a recursive build, so we need to do a little thinking
26 # to get the ordering right.
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.
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.
41 this-makefile := $(lastword $(MAKEFILE_LIST))
42 abs_srctree := $(realpath $(dir $(this-makefile)))
43 abs_output := $(CURDIR)
45 ifneq ($(sub_make_done),1)
47 # Do not use make's built-in rules and variables
48 # (this increases performance and avoids hard-to-debug behaviour)
49 MAKEFLAGS += -rR
51 # Avoid funny character set dependencies
52 unexport LC_ALL
53 LC_COLLATE=C
54 LC_NUMERIC=C
55 export LC_COLLATE LC_NUMERIC
57 # Avoid interference with shell env settings
58 unexport GREP_OPTIONS
60 # Beautify output
61 # ---------------------------------------------------------------------------
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.
67 # e.g.)
68 # quiet_cmd_depmod = DEPMOD $(MODLIB)
69 # cmd_depmod = $(srctree)/scripts/depmod.sh $(DEPMOD) $(KERNELRELEASE)
71 # A simple variant is to prefix commands with $(Q) - that's useful
72 # for commands that shall be hidden in non-verbose mode.
74 # $(Q)$(MAKE) $(build)=scripts/basic
76 # If KBUILD_VERBOSE contains 1, the whole command is echoed.
77 # If KBUILD_VERBOSE contains 2, the reason for rebuilding is printed.
79 # To put more focus on warnings, be less verbose as default
80 # Use 'make V=1' to see the full commands
82 ifeq ("$(origin V)", "command line")
83 KBUILD_VERBOSE = $(V)
84 endif
86 quiet = quiet_
87 Q = @
89 ifneq ($(findstring 1, $(KBUILD_VERBOSE)),)
90 quiet =
91 Q =
92 endif
94 # If the user is running make -s (silent mode), suppress echoing of
95 # commands
96 ifneq ($(findstring s,$(firstword -$(MAKEFLAGS))),)
97 quiet=silent_
98 override KBUILD_VERBOSE :=
99 endif
101 export quiet Q KBUILD_VERBOSE
103 # Call a source code checker (by default, "sparse") as part of the
104 # C compilation.
106 # Use 'make C=1' to enable checking of only re-compiled files.
107 # Use 'make C=2' to enable checking of *all* source files, regardless
108 # of whether they are re-compiled or not.
110 # See the file "Documentation/dev-tools/sparse.rst" for more details,
111 # including where to get the "sparse" utility.
113 ifeq ("$(origin C)", "command line")
114 KBUILD_CHECKSRC = $(C)
115 endif
116 ifndef KBUILD_CHECKSRC
117 KBUILD_CHECKSRC = 0
118 endif
120 export KBUILD_CHECKSRC
122 # Enable "clippy" (a linter) as part of the Rust compilation.
124 # Use 'make CLIPPY=1' to enable it.
125 ifeq ("$(origin CLIPPY)", "command line")
126 KBUILD_CLIPPY := $(CLIPPY)
127 endif
129 export KBUILD_CLIPPY
131 # Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
132 # directory of external module to build. Setting M= takes precedence.
133 ifeq ("$(origin M)", "command line")
134 KBUILD_EXTMOD := $(M)
135 endif
137 ifeq ("$(origin MO)", "command line")
138 KBUILD_EXTMOD_OUTPUT := $(MO)
139 endif
141 $(if $(word 2, $(KBUILD_EXTMOD)), \
142 $(error building multiple external modules is not supported))
144 $(foreach x, % :, $(if $(findstring $x, $(KBUILD_EXTMOD)), \
145 $(error module directory path cannot contain '$x')))
147 # Remove trailing slashes
148 ifneq ($(filter %/, $(KBUILD_EXTMOD)),)
149 KBUILD_EXTMOD := $(shell dirname $(KBUILD_EXTMOD).)
150 endif
152 export KBUILD_EXTMOD
154 # backward compatibility
155 KBUILD_EXTRA_WARN ?= $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)
157 ifeq ("$(origin W)", "command line")
158 KBUILD_EXTRA_WARN := $(W)
159 endif
161 export KBUILD_EXTRA_WARN
163 # Kbuild will save output files in the current working directory.
164 # This does not need to match to the root of the kernel source tree.
166 # For example, you can do this:
168 # cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
170 # If you want to save output files in a different location, there are
171 # two syntaxes to specify it.
173 # 1) O=
174 # Use "make O=dir/to/store/output/files/"
176 # 2) Set KBUILD_OUTPUT
177 # Set the environment variable KBUILD_OUTPUT to point to the output directory.
178 # export KBUILD_OUTPUT=dir/to/store/output/files/; make
180 # The O= assignment takes precedence over the KBUILD_OUTPUT environment
181 # variable.
183 ifeq ("$(origin O)", "command line")
184 KBUILD_OUTPUT := $(O)
185 endif
187 ifdef KBUILD_EXTMOD
188 ifdef KBUILD_OUTPUT
189 objtree := $(realpath $(KBUILD_OUTPUT))
190 $(if $(objtree),,$(error specified kernel directory "$(KBUILD_OUTPUT)" does not exist))
191 else
192 objtree := $(abs_srctree)
193 endif
194 # If Make is invoked from the kernel directory (either kernel
195 # source directory or kernel build directory), external modules
196 # are built in $(KBUILD_EXTMOD) for backward compatibility,
197 # otherwise, built in the current directory.
198 output := $(or $(KBUILD_EXTMOD_OUTPUT),$(if $(filter $(CURDIR),$(objtree) $(abs_srctree)),$(KBUILD_EXTMOD)))
199 # KBUILD_EXTMOD might be a relative path. Remember its absolute path before
200 # Make changes the working directory.
201 srcroot := $(realpath $(KBUILD_EXTMOD))
202 $(if $(srcroot),,$(error specified external module directory "$(KBUILD_EXTMOD)" does not exist))
203 else
204 objtree := .
205 output := $(KBUILD_OUTPUT)
206 endif
208 export objtree srcroot
210 # Do we want to change the working directory?
211 ifneq ($(output),)
212 # $(realpath ...) gets empty if the path does not exist. Run 'mkdir -p' first.
213 $(shell mkdir -p "$(output)")
214 # $(realpath ...) resolves symlinks
215 abs_output := $(realpath $(output))
216 $(if $(abs_output),,$(error failed to create output directory "$(output)"))
217 endif
219 ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
220 $(error source directory cannot contain spaces or colons)
221 endif
223 export sub_make_done := 1
225 endif # sub_make_done
227 ifeq ($(abs_output),$(CURDIR))
228 # Suppress "Entering directory ..." if we are at the final work directory.
229 no-print-directory := --no-print-directory
230 else
231 # Recursion to show "Entering directory ..."
232 need-sub-make := 1
233 endif
235 ifeq ($(filter --no-print-directory, $(MAKEFLAGS)),)
236 # If --no-print-directory is unset, recurse once again to set it.
237 # You may end up recursing into __sub-make twice. This is needed due to the
238 # behavior change in GNU Make 4.4.1.
239 need-sub-make := 1
240 endif
242 ifeq ($(need-sub-make),1)
244 PHONY += $(MAKECMDGOALS) __sub-make
246 $(filter-out $(this-makefile), $(MAKECMDGOALS)) __all: __sub-make
249 # Invoke a second make in the output directory, passing relevant variables
250 __sub-make:
251 $(Q)$(MAKE) $(no-print-directory) -C $(abs_output) \
252 -f $(abs_srctree)/Makefile $(MAKECMDGOALS)
254 else # need-sub-make
256 # We process the rest of the Makefile if this is the final invocation of make
258 ifndef KBUILD_EXTMOD
259 srcroot := $(abs_srctree)
260 endif
262 ifeq ($(srcroot),$(CURDIR))
263 building_out_of_srctree :=
264 else
265 export building_out_of_srctree := 1
266 endif
268 ifdef KBUILD_ABS_SRCTREE
269 # Do nothing. Use the absolute path.
270 else ifeq ($(srcroot),$(CURDIR))
271 # Building in the source.
272 srcroot := .
273 else ifeq ($(srcroot)/,$(dir $(CURDIR)))
274 # Building in a subdirectory of the source.
275 srcroot := ..
276 endif
278 export srctree := $(if $(KBUILD_EXTMOD),$(abs_srctree),$(srcroot))
280 ifdef building_out_of_srctree
281 export VPATH := $(srcroot)
282 else
283 VPATH :=
284 endif
286 # To make sure we do not include .config for any of the *config targets
287 # catch them early, and hand them over to scripts/kconfig/Makefile
288 # It is allowed to specify more targets when calling make, including
289 # mixing *config targets and build targets.
290 # For example 'make oldconfig all'.
291 # Detect when mixed targets is specified, and make a second invocation
292 # of make so .config is not included in this case either (for *config).
294 version_h := include/generated/uapi/linux/version.h
296 clean-targets := %clean mrproper cleandocs
297 no-dot-config-targets := $(clean-targets) \
298 cscope gtags TAGS tags help% %docs check% coccicheck \
299 $(version_h) headers headers_% archheaders archscripts \
300 %asm-generic kernelversion %src-pkg dt_binding_check \
301 outputmakefile rustavailable rustfmt rustfmtcheck
302 no-sync-config-targets := $(no-dot-config-targets) %install modules_sign kernelrelease \
303 image_name
304 single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.rsi %.s %/
306 config-build :=
307 mixed-build :=
308 need-config := 1
309 may-sync-config := 1
310 single-build :=
312 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
313 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
314 need-config :=
315 endif
316 endif
318 ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
319 ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
320 may-sync-config :=
321 endif
322 endif
324 need-compiler := $(may-sync-config)
326 ifneq ($(KBUILD_EXTMOD),)
327 may-sync-config :=
328 endif
330 ifeq ($(KBUILD_EXTMOD),)
331 ifneq ($(filter %config,$(MAKECMDGOALS)),)
332 config-build := 1
333 ifneq ($(words $(MAKECMDGOALS)),1)
334 mixed-build := 1
335 endif
336 endif
337 endif
339 # We cannot build single targets and the others at the same time
340 ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
341 single-build := 1
342 ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
343 mixed-build := 1
344 endif
345 endif
347 # For "make -j clean all", "make -j mrproper defconfig all", etc.
348 ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
349 ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
350 mixed-build := 1
351 endif
352 endif
354 # install and modules_install need also be processed one by one
355 ifneq ($(filter install,$(MAKECMDGOALS)),)
356 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
357 mixed-build := 1
358 endif
359 endif
361 ifdef mixed-build
362 # ===========================================================================
363 # We're called with mixed targets (*config and build targets).
364 # Handle them one by one.
366 PHONY += $(MAKECMDGOALS) __build_one_by_one
368 $(MAKECMDGOALS): __build_one_by_one
371 __build_one_by_one:
372 $(Q)set -e; \
373 for i in $(MAKECMDGOALS); do \
374 $(MAKE) -f $(srctree)/Makefile $$i; \
375 done
377 else # !mixed-build
379 include $(srctree)/scripts/Kbuild.include
381 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
382 KERNELRELEASE = $(call read-file, $(objtree)/include/config/kernel.release)
383 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
384 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
386 include $(srctree)/scripts/subarch.include
388 # Cross compiling and selecting different set of gcc/bin-utils
389 # ---------------------------------------------------------------------------
391 # When performing cross compilation for other architectures ARCH shall be set
392 # to the target architecture. (See arch/* for the possibilities).
393 # ARCH can be set during invocation of make:
394 # make ARCH=arm64
395 # Another way is to have ARCH set in the environment.
396 # The default ARCH is the host where make is executed.
398 # CROSS_COMPILE specify the prefix used for all executables used
399 # during compilation. Only gcc and related bin-utils executables
400 # are prefixed with $(CROSS_COMPILE).
401 # CROSS_COMPILE can be set on the command line
402 # make CROSS_COMPILE=aarch64-linux-gnu-
403 # Alternatively CROSS_COMPILE can be set in the environment.
404 # Default value for CROSS_COMPILE is not to prefix executables
405 # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
406 ARCH ?= $(SUBARCH)
408 # Architecture as present in compile.h
409 UTS_MACHINE := $(ARCH)
410 SRCARCH := $(ARCH)
412 # Additional ARCH settings for x86
413 ifeq ($(ARCH),i386)
414 SRCARCH := x86
415 endif
416 ifeq ($(ARCH),x86_64)
417 SRCARCH := x86
418 endif
420 # Additional ARCH settings for sparc
421 ifeq ($(ARCH),sparc32)
422 SRCARCH := sparc
423 endif
424 ifeq ($(ARCH),sparc64)
425 SRCARCH := sparc
426 endif
428 # Additional ARCH settings for parisc
429 ifeq ($(ARCH),parisc64)
430 SRCARCH := parisc
431 endif
433 export cross_compiling :=
434 ifneq ($(SRCARCH),$(SUBARCH))
435 cross_compiling := 1
436 endif
438 KCONFIG_CONFIG ?= .config
439 export KCONFIG_CONFIG
441 # SHELL used by kbuild
442 CONFIG_SHELL := sh
444 HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
445 HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
446 HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
448 ifneq ($(LLVM),)
449 ifneq ($(filter %/,$(LLVM)),)
450 LLVM_PREFIX := $(LLVM)
451 else ifneq ($(filter -%,$(LLVM)),)
452 LLVM_SUFFIX := $(LLVM)
453 endif
455 HOSTCC = $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
456 HOSTCXX = $(LLVM_PREFIX)clang++$(LLVM_SUFFIX)
457 else
458 HOSTCC = gcc
459 HOSTCXX = g++
460 endif
461 HOSTRUSTC = rustc
462 HOSTPKG_CONFIG = pkg-config
464 KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
465 -O2 -fomit-frame-pointer -std=gnu11
466 KBUILD_USERCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(USERCFLAGS)
467 KBUILD_USERLDFLAGS := $(USERLDFLAGS)
469 # These flags apply to all Rust code in the tree, including the kernel and
470 # host programs.
471 export rust_common_flags := --edition=2021 \
472 -Zbinary_dep_depinfo=y \
473 -Astable_features \
474 -Dnon_ascii_idents \
475 -Dunsafe_op_in_unsafe_fn \
476 -Wmissing_docs \
477 -Wrust_2018_idioms \
478 -Wunreachable_pub \
479 -Wclippy::all \
480 -Wclippy::ignored_unit_patterns \
481 -Wclippy::mut_mut \
482 -Wclippy::needless_bitwise_bool \
483 -Wclippy::needless_continue \
484 -Aclippy::needless_lifetimes \
485 -Wclippy::no_mangle_with_rust_abi \
486 -Wclippy::undocumented_unsafe_blocks \
487 -Wclippy::unnecessary_safety_comment \
488 -Wclippy::unnecessary_safety_doc \
489 -Wrustdoc::missing_crate_level_docs \
490 -Wrustdoc::unescaped_backticks
492 KBUILD_HOSTCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) \
493 $(HOSTCFLAGS) -I $(srctree)/scripts/include
494 KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS) \
495 -I $(srctree)/scripts/include
496 KBUILD_HOSTRUSTFLAGS := $(rust_common_flags) -O -Cstrip=debuginfo \
497 -Zallow-features= $(HOSTRUSTFLAGS)
498 KBUILD_HOSTLDFLAGS := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
499 KBUILD_HOSTLDLIBS := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
501 # Make variables (CC, etc...)
502 CPP = $(CC) -E
503 ifneq ($(LLVM),)
504 CC = $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
505 LD = $(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX)
506 AR = $(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX)
507 NM = $(LLVM_PREFIX)llvm-nm$(LLVM_SUFFIX)
508 OBJCOPY = $(LLVM_PREFIX)llvm-objcopy$(LLVM_SUFFIX)
509 OBJDUMP = $(LLVM_PREFIX)llvm-objdump$(LLVM_SUFFIX)
510 READELF = $(LLVM_PREFIX)llvm-readelf$(LLVM_SUFFIX)
511 STRIP = $(LLVM_PREFIX)llvm-strip$(LLVM_SUFFIX)
512 else
513 CC = $(CROSS_COMPILE)gcc
514 LD = $(CROSS_COMPILE)ld
515 AR = $(CROSS_COMPILE)ar
516 NM = $(CROSS_COMPILE)nm
517 OBJCOPY = $(CROSS_COMPILE)objcopy
518 OBJDUMP = $(CROSS_COMPILE)objdump
519 READELF = $(CROSS_COMPILE)readelf
520 STRIP = $(CROSS_COMPILE)strip
521 endif
522 RUSTC = rustc
523 RUSTDOC = rustdoc
524 RUSTFMT = rustfmt
525 CLIPPY_DRIVER = clippy-driver
526 BINDGEN = bindgen
527 PAHOLE = pahole
528 RESOLVE_BTFIDS = $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
529 LEX = flex
530 YACC = bison
531 AWK = awk
532 INSTALLKERNEL := installkernel
533 PERL = perl
534 PYTHON3 = python3
535 CHECK = sparse
536 BASH = bash
537 KGZIP = gzip
538 KBZIP2 = bzip2
539 KLZOP = lzop
540 LZMA = lzma
541 LZ4 = lz4
542 XZ = xz
543 ZSTD = zstd
545 CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
546 -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
547 NOSTDINC_FLAGS :=
548 CFLAGS_MODULE =
549 RUSTFLAGS_MODULE =
550 AFLAGS_MODULE =
551 LDFLAGS_MODULE =
552 CFLAGS_KERNEL =
553 RUSTFLAGS_KERNEL =
554 AFLAGS_KERNEL =
555 LDFLAGS_vmlinux =
557 # Use USERINCLUDE when you must reference the UAPI directories only.
558 USERINCLUDE := \
559 -I$(srctree)/arch/$(SRCARCH)/include/uapi \
560 -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
561 -I$(srctree)/include/uapi \
562 -I$(objtree)/include/generated/uapi \
563 -include $(srctree)/include/linux/compiler-version.h \
564 -include $(srctree)/include/linux/kconfig.h
566 # Use LINUXINCLUDE when you must reference the include/ directory.
567 # Needed to be compatible with the O= option
568 LINUXINCLUDE := \
569 -I$(srctree)/arch/$(SRCARCH)/include \
570 -I$(objtree)/arch/$(SRCARCH)/include/generated \
571 -I$(srctree)/include \
572 -I$(objtree)/include \
573 $(USERINCLUDE)
575 KBUILD_AFLAGS := -D__ASSEMBLY__ -fno-PIE
577 KBUILD_CFLAGS :=
578 KBUILD_CFLAGS += -std=gnu11
579 KBUILD_CFLAGS += -fshort-wchar
580 KBUILD_CFLAGS += -funsigned-char
581 KBUILD_CFLAGS += -fno-common
582 KBUILD_CFLAGS += -fno-PIE
583 KBUILD_CFLAGS += -fno-strict-aliasing
585 KBUILD_CPPFLAGS := -D__KERNEL__
586 KBUILD_RUSTFLAGS := $(rust_common_flags) \
587 -Cpanic=abort -Cembed-bitcode=n -Clto=n \
588 -Cforce-unwind-tables=n -Ccodegen-units=1 \
589 -Csymbol-mangling-version=v0 \
590 -Crelocation-model=static \
591 -Zfunction-sections=n \
592 -Wclippy::float_arithmetic
594 KBUILD_AFLAGS_KERNEL :=
595 KBUILD_CFLAGS_KERNEL :=
596 KBUILD_RUSTFLAGS_KERNEL :=
597 KBUILD_AFLAGS_MODULE := -DMODULE
598 KBUILD_CFLAGS_MODULE := -DMODULE
599 KBUILD_RUSTFLAGS_MODULE := --cfg MODULE
600 KBUILD_LDFLAGS_MODULE :=
601 KBUILD_LDFLAGS :=
602 CLANG_FLAGS :=
604 ifeq ($(KBUILD_CLIPPY),1)
605 RUSTC_OR_CLIPPY_QUIET := CLIPPY
606 RUSTC_OR_CLIPPY = $(CLIPPY_DRIVER)
607 else
608 RUSTC_OR_CLIPPY_QUIET := RUSTC
609 RUSTC_OR_CLIPPY = $(RUSTC)
610 endif
612 # Allows the usage of unstable features in stable compilers.
613 export RUSTC_BOOTSTRAP := 1
615 # Allows finding `.clippy.toml` in out-of-srctree builds.
616 export CLIPPY_CONF_DIR := $(srctree)
618 export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG
619 export RUSTC RUSTDOC RUSTFMT RUSTC_OR_CLIPPY_QUIET RUSTC_OR_CLIPPY BINDGEN
620 export HOSTRUSTC KBUILD_HOSTRUSTFLAGS
621 export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
622 export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
623 export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
624 export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
625 export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS
627 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
628 export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
629 export KBUILD_RUSTFLAGS RUSTFLAGS_KERNEL RUSTFLAGS_MODULE
630 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
631 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_RUSTFLAGS_MODULE KBUILD_LDFLAGS_MODULE
632 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL KBUILD_RUSTFLAGS_KERNEL
634 # Files to ignore in find ... statements
636 export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o \
637 -name CVS -o -name .pc -o -name .hg -o -name .git \) \
638 -prune -o
640 # ===========================================================================
641 # Rules shared between *config targets and build targets
643 # Basic helpers built in scripts/basic/
644 PHONY += scripts_basic
645 scripts_basic:
646 $(Q)$(MAKE) $(build)=scripts/basic
648 PHONY += outputmakefile
649 ifdef building_out_of_srctree
650 # Before starting out-of-tree build, make sure the source tree is clean.
651 # outputmakefile generates a Makefile in the output directory, if using a
652 # separate output directory. This allows convenient use of make in the
653 # output directory.
654 # At the same time when output Makefile generated, generate .gitignore to
655 # ignore whole output directory
657 ifdef KBUILD_EXTMOD
658 print_env_for_makefile = \
659 echo "export KBUILD_OUTPUT = $(objtree)"; \
660 echo "export KBUILD_EXTMOD = $(realpath $(srcroot))" ; \
661 echo "export KBUILD_EXTMOD_OUTPUT = $(CURDIR)"
662 else
663 print_env_for_makefile = \
664 echo "export KBUILD_OUTPUT = $(CURDIR)"
665 endif
667 quiet_cmd_makefile = GEN Makefile
668 cmd_makefile = { \
669 echo "\# Automatically generated by $(abs_srctree)/Makefile: don't edit"; \
670 $(print_env_for_makefile); \
671 echo "include $(abs_srctree)/Makefile"; \
672 } > Makefile
674 outputmakefile:
675 ifeq ($(KBUILD_EXTMOD),)
676 @if [ -f $(srctree)/.config -o \
677 -d $(srctree)/include/config -o \
678 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
679 echo >&2 "***"; \
680 echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
681 echo >&2 "*** in $(abs_srctree)";\
682 echo >&2 "***"; \
683 false; \
685 else
686 @if [ -f $(srcroot)/modules.order ]; then \
687 echo >&2 "***"; \
688 echo >&2 "*** The external module source tree is not clean."; \
689 echo >&2 "*** Please run 'make -C $(abs_srctree) M=$(realpath $(srcroot)) clean'"; \
690 echo >&2 "***"; \
691 false; \
693 endif
694 $(Q)ln -fsn $(srcroot) source
695 $(call cmd,makefile)
696 $(Q)test -e .gitignore || \
697 { echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
698 endif
700 # The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
701 # Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
702 # CC_VERSION_TEXT and RUSTC_VERSION_TEXT are referenced from Kconfig (so they
703 # need export), and from include/config/auto.conf.cmd to detect the compiler
704 # upgrade.
705 CC_VERSION_TEXT = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1))
706 RUSTC_VERSION_TEXT = $(subst $(pound),,$(shell $(RUSTC) --version 2>/dev/null))
708 ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
709 include $(srctree)/scripts/Makefile.clang
710 endif
712 # Include this also for config targets because some architectures need
713 # cc-cross-prefix to determine CROSS_COMPILE.
714 ifdef need-compiler
715 include $(srctree)/scripts/Makefile.compiler
716 endif
718 ifdef config-build
719 # ===========================================================================
720 # *config targets only - make sure prerequisites are updated, and descend
721 # in scripts/kconfig to make the *config target
723 # Read arch-specific Makefile to set KBUILD_DEFCONFIG as needed.
724 # KBUILD_DEFCONFIG may point out an alternative default configuration
725 # used for 'make defconfig'
726 include $(srctree)/arch/$(SRCARCH)/Makefile
727 export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT RUSTC_VERSION_TEXT
729 config: outputmakefile scripts_basic FORCE
730 $(Q)$(MAKE) $(build)=scripts/kconfig $@
732 %config: outputmakefile scripts_basic FORCE
733 $(Q)$(MAKE) $(build)=scripts/kconfig $@
735 else #!config-build
736 # ===========================================================================
737 # Build targets only - this includes vmlinux, arch-specific targets, clean
738 # targets and others. In general all targets except *config targets.
740 # If building an external module we do not care about the all: rule
741 # but instead __all depend on modules
742 PHONY += all
743 ifeq ($(KBUILD_EXTMOD),)
744 __all: all
745 else
746 __all: modules
747 endif
749 targets :=
751 # Decide whether to build built-in, modular, or both.
752 # Normally, just do built-in.
754 KBUILD_MODULES :=
755 KBUILD_BUILTIN := 1
757 # If we have only "make modules", don't compile built-in objects.
758 ifeq ($(MAKECMDGOALS),modules)
759 KBUILD_BUILTIN :=
760 endif
762 # If we have "make <whatever> modules", compile modules
763 # in addition to whatever we do anyway.
764 # Just "make" or "make all" shall build modules as well
766 ifneq ($(filter all modules nsdeps compile_commands.json clang-%,$(MAKECMDGOALS)),)
767 KBUILD_MODULES := 1
768 endif
770 ifeq ($(MAKECMDGOALS),)
771 KBUILD_MODULES := 1
772 endif
774 export KBUILD_MODULES KBUILD_BUILTIN
776 ifdef need-config
777 include $(objtree)/include/config/auto.conf
778 endif
780 ifeq ($(KBUILD_EXTMOD),)
781 # Objects we will link into vmlinux / subdirs we need to visit
782 core-y :=
783 drivers-y :=
784 libs-y := lib/
785 endif # KBUILD_EXTMOD
787 # The all: target is the default when no target is given on the
788 # command line.
789 # This allow a user to issue only 'make' to build a kernel including modules
790 # Defaults to vmlinux, but the arch makefile usually adds further targets
791 all: vmlinux
793 CFLAGS_GCOV := -fprofile-arcs -ftest-coverage
794 ifdef CONFIG_CC_IS_GCC
795 CFLAGS_GCOV += -fno-tree-loop-im
796 endif
797 export CFLAGS_GCOV
799 # The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
800 ifdef CONFIG_FUNCTION_TRACER
801 CC_FLAGS_FTRACE := -pg
802 endif
804 include $(srctree)/arch/$(SRCARCH)/Makefile
806 ifdef need-config
807 ifdef may-sync-config
808 # Read in dependencies to all Kconfig* files, make sure to run syncconfig if
809 # changes are detected. This should be included after arch/$(SRCARCH)/Makefile
810 # because some architectures define CROSS_COMPILE there.
811 include include/config/auto.conf.cmd
813 $(KCONFIG_CONFIG):
814 @echo >&2 '***'
815 @echo >&2 '*** Configuration file "$@" not found!'
816 @echo >&2 '***'
817 @echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
818 @echo >&2 '*** "make menuconfig" or "make xconfig").'
819 @echo >&2 '***'
820 @/bin/false
822 # The actual configuration files used during the build are stored in
823 # include/generated/ and include/config/. Update them if .config is newer than
824 # include/config/auto.conf (which mirrors .config).
826 # This exploits the 'multi-target pattern rule' trick.
827 # The syncconfig should be executed only once to make all the targets.
828 # (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
830 # Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
831 # so you cannot notice that Kconfig is waiting for the user input.
832 %/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h %/generated/rustc_cfg: $(KCONFIG_CONFIG)
833 $(Q)$(kecho) " SYNC $@"
834 $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
835 else # !may-sync-config
836 # External modules and some install targets need include/generated/autoconf.h
837 # and include/config/auto.conf but do not care if they are up-to-date.
838 # Use auto.conf to show the error message
840 checked-configs := $(addprefix $(objtree)/, include/generated/autoconf.h include/generated/rustc_cfg include/config/auto.conf)
841 missing-configs := $(filter-out $(wildcard $(checked-configs)), $(checked-configs))
843 ifdef missing-configs
844 PHONY += $(objtree)/include/config/auto.conf
846 $(objtree)/include/config/auto.conf:
847 @echo >&2 '***'
848 @echo >&2 '*** ERROR: Kernel configuration is invalid. The following files are missing:'
849 @printf >&2 '*** - %s\n' $(missing-configs)
850 @echo >&2 '*** Run "make oldconfig && make prepare" on kernel source to fix it.'
851 @echo >&2 '***'
852 @/bin/false
853 endif
855 endif # may-sync-config
856 endif # need-config
858 KBUILD_CFLAGS += -fno-delete-null-pointer-checks
860 ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
861 KBUILD_CFLAGS += -O2
862 KBUILD_RUSTFLAGS += -Copt-level=2
863 else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
864 KBUILD_CFLAGS += -Os
865 KBUILD_RUSTFLAGS += -Copt-level=s
866 endif
868 # Always set `debug-assertions` and `overflow-checks` because their default
869 # depends on `opt-level` and `debug-assertions`, respectively.
870 KBUILD_RUSTFLAGS += -Cdebug-assertions=$(if $(CONFIG_RUST_DEBUG_ASSERTIONS),y,n)
871 KBUILD_RUSTFLAGS += -Coverflow-checks=$(if $(CONFIG_RUST_OVERFLOW_CHECKS),y,n)
873 # Tell gcc to never replace conditional load with a non-conditional one
874 ifdef CONFIG_CC_IS_GCC
875 # gcc-10 renamed --param=allow-store-data-races=0 to
876 # -fno-allow-store-data-races.
877 KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
878 KBUILD_CFLAGS += $(call cc-option,-fno-allow-store-data-races)
879 endif
881 ifdef CONFIG_READABLE_ASM
882 # Disable optimizations that make assembler listings hard to read.
883 # reorder blocks reorders the control in the function
884 # ipa clone creates specialized cloned functions
885 # partial inlining inlines only parts of functions
886 KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
887 endif
889 stackp-flags-y := -fno-stack-protector
890 stackp-flags-$(CONFIG_STACKPROTECTOR) := -fstack-protector
891 stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG) := -fstack-protector-strong
893 KBUILD_CFLAGS += $(stackp-flags-y)
895 KBUILD_RUSTFLAGS-$(CONFIG_WERROR) += -Dwarnings
896 KBUILD_RUSTFLAGS += $(KBUILD_RUSTFLAGS-y)
898 ifdef CONFIG_FRAME_POINTER
899 KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
900 KBUILD_RUSTFLAGS += -Cforce-frame-pointers=y
901 else
902 # Some targets (ARM with Thumb2, for example), can't be built with frame
903 # pointers. For those, we don't have FUNCTION_TRACER automatically
904 # select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
905 # incompatible with -fomit-frame-pointer with current GCC, so we don't use
906 # -fomit-frame-pointer with FUNCTION_TRACER.
907 # In the Rust target specification, "frame-pointer" is set explicitly
908 # to "may-omit".
909 ifndef CONFIG_FUNCTION_TRACER
910 KBUILD_CFLAGS += -fomit-frame-pointer
911 endif
912 endif
914 # Initialize all stack variables with a 0xAA pattern.
915 ifdef CONFIG_INIT_STACK_ALL_PATTERN
916 KBUILD_CFLAGS += -ftrivial-auto-var-init=pattern
917 endif
919 # Initialize all stack variables with a zero value.
920 ifdef CONFIG_INIT_STACK_ALL_ZERO
921 KBUILD_CFLAGS += -ftrivial-auto-var-init=zero
922 ifdef CONFIG_CC_HAS_AUTO_VAR_INIT_ZERO_ENABLER
923 # https://github.com/llvm/llvm-project/issues/44842
924 CC_AUTO_VAR_INIT_ZERO_ENABLER := -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
925 export CC_AUTO_VAR_INIT_ZERO_ENABLER
926 KBUILD_CFLAGS += $(CC_AUTO_VAR_INIT_ZERO_ENABLER)
927 endif
928 endif
930 # While VLAs have been removed, GCC produces unreachable stack probes
931 # for the randomize_kstack_offset feature. Disable it for all compilers.
932 KBUILD_CFLAGS += $(call cc-option, -fno-stack-clash-protection)
934 # Clear used registers at func exit (to reduce data lifetime and ROP gadgets).
935 ifdef CONFIG_ZERO_CALL_USED_REGS
936 KBUILD_CFLAGS += -fzero-call-used-regs=used-gpr
937 endif
939 ifdef CONFIG_FUNCTION_TRACER
940 ifdef CONFIG_FTRACE_MCOUNT_USE_CC
941 CC_FLAGS_FTRACE += -mrecord-mcount
942 ifdef CONFIG_HAVE_NOP_MCOUNT
943 ifeq ($(call cc-option-yn, -mnop-mcount),y)
944 CC_FLAGS_FTRACE += -mnop-mcount
945 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
946 endif
947 endif
948 endif
949 ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
950 ifdef CONFIG_HAVE_OBJTOOL_NOP_MCOUNT
951 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
952 endif
953 endif
954 ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
955 ifdef CONFIG_HAVE_C_RECORDMCOUNT
956 BUILD_C_RECORDMCOUNT := y
957 export BUILD_C_RECORDMCOUNT
958 endif
959 endif
960 ifdef CONFIG_HAVE_FENTRY
961 # s390-linux-gnu-gcc did not support -mfentry until gcc-9.
962 ifeq ($(call cc-option-yn, -mfentry),y)
963 CC_FLAGS_FTRACE += -mfentry
964 CC_FLAGS_USING += -DCC_USING_FENTRY
965 endif
966 endif
967 export CC_FLAGS_FTRACE
968 KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
969 KBUILD_AFLAGS += $(CC_FLAGS_USING)
970 endif
972 # We trigger additional mismatches with less inlining
973 ifdef CONFIG_DEBUG_SECTION_MISMATCH
974 KBUILD_CFLAGS += -fno-inline-functions-called-once
975 endif
977 # `rustc`'s `-Zfunction-sections` applies to data too (as of 1.59.0).
978 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
979 KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
980 KBUILD_RUSTFLAGS_KERNEL += -Zfunction-sections=y
981 LDFLAGS_vmlinux += --gc-sections
982 endif
984 ifdef CONFIG_SHADOW_CALL_STACK
985 ifndef CONFIG_DYNAMIC_SCS
986 CC_FLAGS_SCS := -fsanitize=shadow-call-stack
987 KBUILD_CFLAGS += $(CC_FLAGS_SCS)
988 KBUILD_RUSTFLAGS += -Zsanitizer=shadow-call-stack
989 endif
990 export CC_FLAGS_SCS
991 endif
993 ifdef CONFIG_LTO_CLANG
994 ifdef CONFIG_LTO_CLANG_THIN
995 CC_FLAGS_LTO := -flto=thin -fsplit-lto-unit
996 else
997 CC_FLAGS_LTO := -flto
998 endif
999 CC_FLAGS_LTO += -fvisibility=hidden
1001 # Limit inlining across translation units to reduce binary size
1002 KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
1003 endif
1005 ifdef CONFIG_LTO
1006 KBUILD_CFLAGS += -fno-lto $(CC_FLAGS_LTO)
1007 KBUILD_AFLAGS += -fno-lto
1008 export CC_FLAGS_LTO
1009 endif
1011 ifdef CONFIG_CFI_CLANG
1012 CC_FLAGS_CFI := -fsanitize=kcfi
1013 ifdef CONFIG_CFI_ICALL_NORMALIZE_INTEGERS
1014 CC_FLAGS_CFI += -fsanitize-cfi-icall-experimental-normalize-integers
1015 endif
1016 ifdef CONFIG_RUST
1017 # Always pass -Zsanitizer-cfi-normalize-integers as CONFIG_RUST selects
1018 # CONFIG_CFI_ICALL_NORMALIZE_INTEGERS.
1019 RUSTC_FLAGS_CFI := -Zsanitizer=kcfi -Zsanitizer-cfi-normalize-integers
1020 KBUILD_RUSTFLAGS += $(RUSTC_FLAGS_CFI)
1021 export RUSTC_FLAGS_CFI
1022 endif
1023 KBUILD_CFLAGS += $(CC_FLAGS_CFI)
1024 export CC_FLAGS_CFI
1025 endif
1027 # Architectures can define flags to add/remove for floating-point support
1028 CC_FLAGS_FPU += -D_LINUX_FPU_COMPILATION_UNIT
1029 export CC_FLAGS_FPU
1030 export CC_FLAGS_NO_FPU
1032 ifneq ($(CONFIG_FUNCTION_ALIGNMENT),0)
1033 # Set the minimal function alignment. Use the newer GCC option
1034 # -fmin-function-alignment if it is available, or fall back to -falign-funtions.
1035 # See also CONFIG_CC_HAS_SANE_FUNCTION_ALIGNMENT.
1036 ifdef CONFIG_CC_HAS_MIN_FUNCTION_ALIGNMENT
1037 KBUILD_CFLAGS += -fmin-function-alignment=$(CONFIG_FUNCTION_ALIGNMENT)
1038 else
1039 KBUILD_CFLAGS += -falign-functions=$(CONFIG_FUNCTION_ALIGNMENT)
1040 endif
1041 endif
1043 # arch Makefile may override CC so keep this after arch Makefile is included
1044 NOSTDINC_FLAGS += -nostdinc
1046 # To gain proper coverage for CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE,
1047 # the kernel uses only C99 flexible arrays for dynamically sized trailing
1048 # arrays. Enforce this for everything that may examine structure sizes and
1049 # perform bounds checking.
1050 KBUILD_CFLAGS += $(call cc-option, -fstrict-flex-arrays=3)
1052 #Currently, disable -Wstringop-overflow for GCC 11, globally.
1053 KBUILD_CFLAGS-$(CONFIG_CC_NO_STRINGOP_OVERFLOW) += $(call cc-option, -Wno-stringop-overflow)
1054 KBUILD_CFLAGS-$(CONFIG_CC_STRINGOP_OVERFLOW) += $(call cc-option, -Wstringop-overflow)
1056 # disable invalid "can't wrap" optimizations for signed / pointers
1057 KBUILD_CFLAGS += -fno-strict-overflow
1059 # Make sure -fstack-check isn't enabled (like gentoo apparently did)
1060 KBUILD_CFLAGS += -fno-stack-check
1062 # conserve stack if available
1063 ifdef CONFIG_CC_IS_GCC
1064 KBUILD_CFLAGS += -fconserve-stack
1065 endif
1067 # change __FILE__ to the relative path to the source directory
1068 ifdef building_out_of_srctree
1069 KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srcroot)/=)
1070 endif
1072 # include additional Makefiles when needed
1073 include-y := scripts/Makefile.extrawarn
1074 include-$(CONFIG_DEBUG_INFO) += scripts/Makefile.debug
1075 include-$(CONFIG_DEBUG_INFO_BTF)+= scripts/Makefile.btf
1076 include-$(CONFIG_KASAN) += scripts/Makefile.kasan
1077 include-$(CONFIG_KCSAN) += scripts/Makefile.kcsan
1078 include-$(CONFIG_KMSAN) += scripts/Makefile.kmsan
1079 include-$(CONFIG_UBSAN) += scripts/Makefile.ubsan
1080 include-$(CONFIG_KCOV) += scripts/Makefile.kcov
1081 include-$(CONFIG_RANDSTRUCT) += scripts/Makefile.randstruct
1082 include-$(CONFIG_AUTOFDO_CLANG) += scripts/Makefile.autofdo
1083 include-$(CONFIG_PROPELLER_CLANG) += scripts/Makefile.propeller
1084 include-$(CONFIG_GCC_PLUGINS) += scripts/Makefile.gcc-plugins
1086 include $(addprefix $(srctree)/, $(include-y))
1088 # scripts/Makefile.gcc-plugins is intentionally included last.
1089 # Do not add $(call cc-option,...) below this line. When you build the kernel
1090 # from the clean source tree, the GCC plugins do not exist at this point.
1092 # Add user supplied CPPFLAGS, AFLAGS, CFLAGS and RUSTFLAGS as the last assignments
1093 KBUILD_CPPFLAGS += $(KCPPFLAGS)
1094 KBUILD_AFLAGS += $(KAFLAGS)
1095 KBUILD_CFLAGS += $(KCFLAGS)
1096 KBUILD_RUSTFLAGS += $(KRUSTFLAGS)
1098 KBUILD_LDFLAGS_MODULE += --build-id=sha1
1099 LDFLAGS_vmlinux += --build-id=sha1
1101 KBUILD_LDFLAGS += -z noexecstack
1102 ifeq ($(CONFIG_LD_IS_BFD),y)
1103 KBUILD_LDFLAGS += $(call ld-option,--no-warn-rwx-segments)
1104 endif
1106 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1107 LDFLAGS_vmlinux += -X
1108 endif
1110 ifeq ($(CONFIG_RELR),y)
1111 # ld.lld before 15 did not support -z pack-relative-relocs.
1112 LDFLAGS_vmlinux += $(call ld-option,--pack-dyn-relocs=relr,-z pack-relative-relocs)
1113 endif
1115 # We never want expected sections to be placed heuristically by the
1116 # linker. All sections should be explicitly named in the linker script.
1117 ifdef CONFIG_LD_ORPHAN_WARN
1118 LDFLAGS_vmlinux += --orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL)
1119 endif
1121 # Align the bit size of userspace programs with the kernel
1122 KBUILD_USERCFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1123 KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1125 # make the checker run with the right architecture
1126 CHECKFLAGS += --arch=$(ARCH)
1128 # insure the checker run with the right endianness
1129 CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1131 # the checker needs the correct machine size
1132 CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1134 # Default kernel image to build when no specific target is given.
1135 # KBUILD_IMAGE may be overruled on the command line or
1136 # set in the environment
1137 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
1138 # this default value
1139 export KBUILD_IMAGE ?= vmlinux
1142 # INSTALL_PATH specifies where to place the updated kernel and system map
1143 # images. Default is /boot, but you can set it to other values
1144 export INSTALL_PATH ?= /boot
1147 # INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1148 # Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1149 # an argument if needed. Otherwise it defaults to the kernel install path
1151 export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1154 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1155 # relocations required by build roots. This is not defined in the
1156 # makefile but the argument can be passed to make if needed.
1159 MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1160 export MODLIB
1162 PHONY += prepare0
1164 ifeq ($(KBUILD_EXTMOD),)
1166 build-dir := .
1167 clean-dirs := $(sort . Documentation \
1168 $(patsubst %/,%,$(filter %/, $(core-) \
1169 $(drivers-) $(libs-))))
1171 export ARCH_CORE := $(core-y)
1172 export ARCH_LIB := $(filter %/, $(libs-y))
1173 export ARCH_DRIVERS := $(drivers-y) $(drivers-m)
1174 # Externally visible symbols (used by link-vmlinux.sh)
1176 KBUILD_VMLINUX_OBJS := ./built-in.a
1177 ifdef CONFIG_MODULES
1178 KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1179 KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1180 else
1181 KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1182 endif
1184 export KBUILD_VMLINUX_LIBS
1185 export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
1187 ifdef CONFIG_TRIM_UNUSED_KSYMS
1188 # For the kernel to actually contain only the needed exported symbols,
1189 # we have to build modules as well to determine what those symbols are.
1190 KBUILD_MODULES := 1
1191 endif
1193 # '$(AR) mPi' needs 'T' to workaround the bug of llvm-ar <= 14
1194 quiet_cmd_ar_vmlinux.a = AR $@
1195 cmd_ar_vmlinux.a = \
1196 rm -f $@; \
1197 $(AR) cDPrST $@ $(KBUILD_VMLINUX_OBJS); \
1198 $(AR) mPiT $$($(AR) t $@ | sed -n 1p) $@ $$($(AR) t $@ | grep -F -f $(srctree)/scripts/head-object-list.txt)
1200 targets += vmlinux.a
1201 vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt FORCE
1202 $(call if_changed,ar_vmlinux.a)
1204 PHONY += vmlinux_o
1205 vmlinux_o: vmlinux.a $(KBUILD_VMLINUX_LIBS)
1206 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o
1208 vmlinux.o modules.builtin.modinfo modules.builtin: vmlinux_o
1211 PHONY += vmlinux
1212 # LDFLAGS_vmlinux in the top Makefile defines linker flags for the top vmlinux,
1213 # not for decompressors. LDFLAGS_vmlinux in arch/*/boot/compressed/Makefile is
1214 # unrelated; the decompressors just happen to have the same base name,
1215 # arch/*/boot/compressed/vmlinux.
1216 # Export LDFLAGS_vmlinux only to scripts/Makefile.vmlinux.
1218 # _LDFLAGS_vmlinux is a workaround for the 'private export' bug:
1219 # https://savannah.gnu.org/bugs/?61463
1220 # For Make > 4.4, the following simple code will work:
1221 # vmlinux: private export LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1222 vmlinux: private _LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1223 vmlinux: export LDFLAGS_vmlinux = $(_LDFLAGS_vmlinux)
1224 vmlinux: vmlinux.o $(KBUILD_LDS) modpost
1225 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux
1227 # The actual objects are generated when descending,
1228 # make sure no implicit rule kicks in
1229 $(sort $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)): . ;
1231 ifeq ($(origin KERNELRELEASE),file)
1232 filechk_kernel.release = $(srctree)/scripts/setlocalversion $(srctree)
1233 else
1234 filechk_kernel.release = echo $(KERNELRELEASE)
1235 endif
1237 # Store (new) KERNELRELEASE string in include/config/kernel.release
1238 include/config/kernel.release: FORCE
1239 $(call filechk,kernel.release)
1241 # Additional helpers built in scripts/
1242 # Carefully list dependencies so we do not try to build scripts twice
1243 # in parallel
1244 PHONY += scripts
1245 scripts: scripts_basic scripts_dtc
1246 $(Q)$(MAKE) $(build)=$(@)
1248 # Things we need to do before we recursively start building the kernel
1249 # or the modules are listed in "prepare".
1250 # A multi level approach is used. prepareN is processed before prepareN-1.
1251 # archprepare is used in arch Makefiles and when processed asm symlink,
1252 # version.h and scripts_basic is processed / created.
1254 PHONY += prepare archprepare
1256 archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1257 asm-generic $(version_h) include/generated/utsrelease.h \
1258 include/generated/compile.h include/generated/autoconf.h \
1259 include/generated/rustc_cfg remove-stale-files
1261 prepare0: archprepare
1262 $(Q)$(MAKE) $(build)=scripts/mod
1263 $(Q)$(MAKE) $(build)=. prepare
1265 # All the preparing..
1266 prepare: prepare0
1267 ifdef CONFIG_RUST
1268 +$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh
1269 $(Q)$(MAKE) $(build)=rust
1270 endif
1272 PHONY += remove-stale-files
1273 remove-stale-files:
1274 $(Q)$(srctree)/scripts/remove-stale-files
1276 # Support for using generic headers in asm-generic
1277 asm-generic := -f $(srctree)/scripts/Makefile.asm-headers obj
1279 PHONY += asm-generic uapi-asm-generic
1280 asm-generic: uapi-asm-generic
1281 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1282 generic=include/asm-generic
1283 uapi-asm-generic:
1284 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1285 generic=include/uapi/asm-generic
1287 # Generate some files
1288 # ---------------------------------------------------------------------------
1290 # KERNELRELEASE can change from a few different places, meaning version.h
1291 # needs to be updated, so this check is forced on all builds
1293 uts_len := 64
1294 define filechk_utsrelease.h
1295 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1296 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1297 exit 1; \
1298 fi; \
1299 echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1300 endef
1302 define filechk_version.h
1303 if [ $(SUBLEVEL) -gt 255 ]; then \
1304 echo \#define LINUX_VERSION_CODE $(shell \
1305 expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1306 else \
1307 echo \#define LINUX_VERSION_CODE $(shell \
1308 expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1309 fi; \
1310 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + \
1311 ((c) > 255 ? 255 : (c)))'; \
1312 echo \#define LINUX_VERSION_MAJOR $(VERSION); \
1313 echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL); \
1314 echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1315 endef
1317 $(version_h): private PATCHLEVEL := $(or $(PATCHLEVEL), 0)
1318 $(version_h): private SUBLEVEL := $(or $(SUBLEVEL), 0)
1319 $(version_h): FORCE
1320 $(call filechk,version.h)
1322 include/generated/utsrelease.h: include/config/kernel.release FORCE
1323 $(call filechk,utsrelease.h)
1325 filechk_compile.h = $(srctree)/scripts/mkcompile_h \
1326 "$(UTS_MACHINE)" "$(CONFIG_CC_VERSION_TEXT)" "$(LD)"
1328 include/generated/compile.h: FORCE
1329 $(call filechk,compile.h)
1331 PHONY += headerdep
1332 headerdep:
1333 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1334 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1336 # ---------------------------------------------------------------------------
1337 # Kernel headers
1339 #Default location for installed headers
1340 export INSTALL_HDR_PATH = $(objtree)/usr
1342 quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1343 cmd_headers_install = \
1344 mkdir -p $(INSTALL_HDR_PATH); \
1345 rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1346 usr/include $(INSTALL_HDR_PATH)
1348 PHONY += headers_install
1349 headers_install: headers
1350 $(call cmd,headers_install)
1352 PHONY += archheaders archscripts
1354 hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1356 PHONY += headers
1357 headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1358 $(if $(filter um, $(SRCARCH)), $(error Headers not exportable for UML))
1359 $(Q)$(MAKE) $(hdr-inst)=include/uapi
1360 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1362 ifdef CONFIG_HEADERS_INSTALL
1363 prepare: headers
1364 endif
1366 PHONY += scripts_unifdef
1367 scripts_unifdef: scripts_basic
1368 $(Q)$(MAKE) $(build)=scripts scripts/unifdef
1370 # ---------------------------------------------------------------------------
1371 # Install
1373 # Many distributions have the custom install script, /sbin/installkernel.
1374 # If DKMS is installed, 'make install' will eventually recurse back
1375 # to this Makefile to build and install external modules.
1376 # Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
1378 quiet_cmd_install = INSTALL $(INSTALL_PATH)
1379 cmd_install = unset sub_make_done; $(srctree)/scripts/install.sh
1381 # ---------------------------------------------------------------------------
1382 # vDSO install
1384 PHONY += vdso_install
1385 vdso_install: export INSTALL_FILES = $(vdso-install-y)
1386 vdso_install:
1387 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vdsoinst
1389 # ---------------------------------------------------------------------------
1390 # Tools
1392 ifdef CONFIG_OBJTOOL
1393 prepare: tools/objtool
1394 endif
1396 ifdef CONFIG_BPF
1397 ifdef CONFIG_DEBUG_INFO_BTF
1398 prepare: tools/bpf/resolve_btfids
1399 endif
1400 endif
1402 # The tools build system is not a part of Kbuild and tends to introduce
1403 # its own unique issues. If you need to integrate a new tool into Kbuild,
1404 # please consider locating that tool outside the tools/ tree and using the
1405 # standard Kbuild "hostprogs" syntax instead of adding a new tools/* entry
1406 # here. See Documentation/kbuild/makefiles.rst for details.
1408 PHONY += resolve_btfids_clean
1410 resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1412 # tools/bpf/resolve_btfids directory might not exist
1413 # in output directory, skip its clean in that case
1414 resolve_btfids_clean:
1415 ifneq ($(wildcard $(resolve_btfids_O)),)
1416 $(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1417 endif
1419 # Clear a bunch of variables before executing the submake
1420 ifeq ($(quiet),silent_)
1421 tools_silent=s
1422 endif
1424 tools/: FORCE
1425 $(Q)mkdir -p $(objtree)/tools
1426 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1428 tools/%: FORCE
1429 $(Q)mkdir -p $(objtree)/tools
1430 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1432 # ---------------------------------------------------------------------------
1433 # Kernel selftest
1435 PHONY += kselftest
1436 kselftest: headers
1437 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1439 kselftest-%: headers FORCE
1440 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1442 PHONY += kselftest-merge
1443 kselftest-merge:
1444 $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1445 $(Q)find $(srctree)/tools/testing/selftests -name config -o -name config.$(UTS_MACHINE) | \
1446 xargs $(srctree)/scripts/kconfig/merge_config.sh -y -m $(objtree)/.config
1447 $(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1449 # ---------------------------------------------------------------------------
1450 # Devicetree files
1452 ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1453 dtstree := arch/$(SRCARCH)/boot/dts
1454 endif
1456 ifneq ($(dtstree),)
1458 %.dtb: dtbs_prepare
1459 $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1461 %.dtbo: dtbs_prepare
1462 $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1464 PHONY += dtbs dtbs_prepare dtbs_install dtbs_check
1465 dtbs: dtbs_prepare
1466 $(Q)$(MAKE) $(build)=$(dtstree) need-dtbslist=1
1468 # include/config/kernel.release is actually needed when installing DTBs because
1469 # INSTALL_DTBS_PATH contains $(KERNELRELEASE). However, we do not want to make
1470 # dtbs_install depend on it as dtbs_install may run as root.
1471 dtbs_prepare: include/config/kernel.release scripts_dtc
1473 ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1474 export CHECK_DTBS=y
1475 endif
1477 ifneq ($(CHECK_DTBS),)
1478 dtbs_prepare: dt_binding_schemas
1479 endif
1481 dtbs_check: dtbs
1483 dtbs_install:
1484 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.dtbinst obj=$(dtstree)
1486 ifdef CONFIG_OF_EARLY_FLATTREE
1487 all: dtbs
1488 endif
1490 ifdef CONFIG_GENERIC_BUILTIN_DTB
1491 vmlinux: dtbs
1492 endif
1494 endif
1496 PHONY += scripts_dtc
1497 scripts_dtc: scripts_basic
1498 $(Q)$(MAKE) $(build)=scripts/dtc
1500 ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1501 export CHECK_DTBS=y
1502 endif
1504 PHONY += dt_binding_check dt_binding_schemas
1505 dt_binding_check: dt_binding_schemas scripts_dtc
1506 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1508 dt_binding_schemas:
1509 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1511 PHONY += dt_compatible_check
1512 dt_compatible_check: dt_binding_schemas
1513 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1515 # ---------------------------------------------------------------------------
1516 # Modules
1518 ifdef CONFIG_MODULES
1520 # By default, build modules as well
1522 all: modules
1524 # When we're building modules with modversions, we need to consider
1525 # the built-in objects during the descend as well, in order to
1526 # make sure the checksums are up to date before we record them.
1527 ifdef CONFIG_MODVERSIONS
1528 KBUILD_BUILTIN := 1
1529 endif
1531 # Build modules
1534 # *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFO_BTF_MODULES
1535 # is an exception.
1536 ifdef CONFIG_DEBUG_INFO_BTF_MODULES
1537 KBUILD_BUILTIN := 1
1538 modules: vmlinux
1539 endif
1541 modules: modules_prepare
1543 # Target to prepare building external modules
1544 modules_prepare: prepare
1545 $(Q)$(MAKE) $(build)=scripts scripts/module.lds
1547 endif # CONFIG_MODULES
1550 # Cleaning is done on three levels.
1551 # make clean Delete most generated files
1552 # Leave enough to build external modules
1553 # make mrproper Delete the current configuration, and all generated files
1554 # make distclean Remove editor backup files, patch leftover files and the like
1556 # Directories & files removed with 'make clean'
1557 CLEAN_FILES += vmlinux.symvers modules-only.symvers \
1558 modules.builtin modules.builtin.modinfo modules.nsdeps \
1559 modules.builtin.ranges vmlinux.o.map \
1560 compile_commands.json rust/test \
1561 rust-project.json .vmlinux.objs .vmlinux.export.c \
1562 .builtin-dtbs-list .builtin-dtb.S
1564 # Directories & files removed with 'make mrproper'
1565 MRPROPER_FILES += include/config include/generated \
1566 arch/$(SRCARCH)/include/generated .objdiff \
1567 debian snap tar-install PKGBUILD pacman \
1568 .config .config.old .version \
1569 Module.symvers \
1570 certs/signing_key.pem \
1571 certs/x509.genkey \
1572 vmlinux-gdb.py \
1573 rpmbuild \
1574 rust/libmacros.so
1576 # clean - Delete most, but leave enough to build external modules
1578 clean: private rm-files := $(CLEAN_FILES)
1580 PHONY += archclean vmlinuxclean
1582 vmlinuxclean:
1583 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1584 $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1586 clean: archclean vmlinuxclean resolve_btfids_clean
1588 # mrproper - Delete all generated files, including .config
1590 mrproper: private rm-files := $(MRPROPER_FILES)
1591 mrproper-dirs := $(addprefix _mrproper_,scripts)
1593 PHONY += $(mrproper-dirs) mrproper
1594 $(mrproper-dirs):
1595 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1597 mrproper: clean $(mrproper-dirs)
1598 $(call cmd,rmfiles)
1599 @find . $(RCS_FIND_IGNORE) \
1600 \( -name '*.rmeta' \) \
1601 -type f -print | xargs rm -f
1603 # distclean
1605 PHONY += distclean
1607 distclean: mrproper
1608 @find . $(RCS_FIND_IGNORE) \
1609 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1610 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1611 -o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1612 -o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1613 -type f -print | xargs rm -f
1616 # Packaging of the kernel to various formats
1617 # ---------------------------------------------------------------------------
1619 %src-pkg: FORCE
1620 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1621 %pkg: include/config/kernel.release FORCE
1622 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1624 # Brief documentation of the typical targets used
1625 # ---------------------------------------------------------------------------
1627 boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1628 boards := $(sort $(notdir $(boards)))
1629 board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1630 board-dirs := $(sort $(notdir $(board-dirs:/=)))
1632 PHONY += help
1633 help:
1634 @echo 'Cleaning targets:'
1635 @echo ' clean - Remove most generated files but keep the config and'
1636 @echo ' enough build support to build external modules'
1637 @echo ' mrproper - Remove all generated files + config + various backup files'
1638 @echo ' distclean - mrproper + remove editor backup and patch files'
1639 @echo ''
1640 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1641 @echo ''
1642 @echo 'Other generic targets:'
1643 @echo ' all - Build all targets marked with [*]'
1644 @echo '* vmlinux - Build the bare kernel'
1645 @echo '* modules - Build all modules'
1646 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1647 @echo ' vdso_install - Install unstripped vdso to INSTALL_MOD_PATH (default: /)'
1648 @echo ' dir/ - Build all files in dir and below'
1649 @echo ' dir/file.[ois] - Build specified target only'
1650 @echo ' dir/file.ll - Build the LLVM assembly file'
1651 @echo ' (requires compiler support for LLVM assembly generation)'
1652 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1653 @echo ' (requires a recent binutils and recent build (System.map))'
1654 @echo ' dir/file.ko - Build module including final link'
1655 @echo ' modules_prepare - Set up for building external modules'
1656 @echo ' tags/TAGS - Generate tags file for editors'
1657 @echo ' cscope - Generate cscope index'
1658 @echo ' gtags - Generate GNU GLOBAL index'
1659 @echo ' kernelrelease - Output the release version string (use with make -s)'
1660 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1661 @echo ' image_name - Output the image name (use with make -s)'
1662 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1663 echo ' (default: $(INSTALL_HDR_PATH))'; \
1664 echo ''
1665 @echo 'Static analysers:'
1666 @echo ' checkstack - Generate a list of stack hogs and consider all functions'
1667 @echo ' with a stack size larger than MINSTACKSIZE (default: 100)'
1668 @echo ' versioncheck - Sanity check on version.h usage'
1669 @echo ' includecheck - Check for duplicate included header files'
1670 @echo ' headerdep - Detect inclusion cycles in headers'
1671 @echo ' coccicheck - Check with Coccinelle'
1672 @echo ' clang-analyzer - Check with clang static analyzer'
1673 @echo ' clang-tidy - Check with clang-tidy'
1674 @echo ''
1675 @echo 'Tools:'
1676 @echo ' nsdeps - Generate missing symbol namespace dependencies'
1677 @echo ''
1678 @echo 'Kernel selftest:'
1679 @echo ' kselftest - Build and run kernel selftest'
1680 @echo ' Build, install, and boot kernel before'
1681 @echo ' running kselftest on it'
1682 @echo ' Run as root for full coverage'
1683 @echo ' kselftest-all - Build kernel selftest'
1684 @echo ' kselftest-install - Build and install kernel selftest'
1685 @echo ' kselftest-clean - Remove all generated kselftest files'
1686 @echo ' kselftest-merge - Merge all the config dependencies of'
1687 @echo ' kselftest to existing .config.'
1688 @echo ''
1689 @echo 'Rust targets:'
1690 @echo ' rustavailable - Checks whether the Rust toolchain is'
1691 @echo ' available and, if not, explains why.'
1692 @echo ' rustfmt - Reformat all the Rust code in the kernel'
1693 @echo ' rustfmtcheck - Checks if all the Rust code in the kernel'
1694 @echo ' is formatted, printing a diff otherwise.'
1695 @echo ' rustdoc - Generate Rust documentation'
1696 @echo ' (requires kernel .config)'
1697 @echo ' rusttest - Runs the Rust tests'
1698 @echo ' (requires kernel .config; downloads external repos)'
1699 @echo ' rust-analyzer - Generate rust-project.json rust-analyzer support file'
1700 @echo ' (requires kernel .config)'
1701 @echo ' dir/file.[os] - Build specified target only'
1702 @echo ' dir/file.rsi - Build macro expanded source, similar to C preprocessing.'
1703 @echo ' Run with RUSTFMT=n to skip reformatting if needed.'
1704 @echo ' The output is not intended to be compilable.'
1705 @echo ' dir/file.ll - Build the LLVM assembly file'
1706 @echo ''
1707 @$(if $(dtstree), \
1708 echo 'Devicetree:'; \
1709 echo '* dtbs - Build device tree blobs for enabled boards'; \
1710 echo ' dtbs_install - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1711 echo ' dt_binding_check - Validate device tree binding documents and examples'; \
1712 echo ' dt_binding_schemas - Build processed device tree binding schemas'; \
1713 echo ' dtbs_check - Validate device tree source files';\
1714 echo '')
1716 @echo 'Userspace tools targets:'
1717 @echo ' use "make tools/help"'
1718 @echo ' or "cd tools; make help"'
1719 @echo ''
1720 @echo 'Kernel packaging:'
1721 @$(MAKE) -f $(srctree)/scripts/Makefile.package help
1722 @echo ''
1723 @echo 'Documentation targets:'
1724 @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1725 @echo ''
1726 @echo 'Architecture-specific targets ($(SRCARCH)):'
1727 @$(or $(archhelp),\
1728 echo ' No architecture-specific help defined for $(SRCARCH)')
1729 @echo ''
1730 @$(if $(boards), \
1731 $(foreach b, $(boards), \
1732 printf " %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1733 echo '')
1734 @$(if $(board-dirs), \
1735 $(foreach b, $(board-dirs), \
1736 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1737 printf " %-16s - Show all of the above\\n" help-boards; \
1738 echo '')
1740 @echo ' make V=n [targets] 1: verbose build'
1741 @echo ' 2: give reason for rebuild of target'
1742 @echo ' V=1 and V=2 can be combined with V=12'
1743 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1744 @echo ' make C=1 [targets] Check re-compiled c source with $$CHECK'
1745 @echo ' (sparse by default)'
1746 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1747 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1748 @echo ' make W=n [targets] Enable extra build checks, n=1,2,3,c,e where'
1749 @echo ' 1: warnings which may be relevant and do not occur too often'
1750 @echo ' 2: warnings which occur quite often but may still be relevant'
1751 @echo ' 3: more obscure warnings, can most likely be ignored'
1752 @echo ' c: extra checks in the configuration stage (Kconfig)'
1753 @echo ' e: warnings are being treated as errors'
1754 @echo ' Multiple levels can be combined with W=12 or W=123'
1755 @$(if $(dtstree), \
1756 echo ' make CHECK_DTBS=1 [targets] Check all generated dtb files against schema'; \
1757 echo ' This can be applied both to "dtbs" and to individual "foo.dtb" targets' ; \
1759 @echo ''
1760 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1761 @echo 'For further info see the ./README file'
1764 help-board-dirs := $(addprefix help-,$(board-dirs))
1766 help-boards: $(help-board-dirs)
1768 boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1770 $(help-board-dirs): help-%:
1771 @echo 'Architecture-specific targets ($(SRCARCH) $*):'
1772 @$(if $(boards-per-dir), \
1773 $(foreach b, $(boards-per-dir), \
1774 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1775 echo '')
1778 # Documentation targets
1779 # ---------------------------------------------------------------------------
1780 DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1781 linkcheckdocs dochelp refcheckdocs texinfodocs infodocs
1782 PHONY += $(DOC_TARGETS)
1783 $(DOC_TARGETS):
1784 $(Q)$(MAKE) $(build)=Documentation $@
1787 # Rust targets
1788 # ---------------------------------------------------------------------------
1790 # "Is Rust available?" target
1791 PHONY += rustavailable
1792 rustavailable:
1793 +$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh && echo "Rust is available!"
1795 # Documentation target
1797 # Using the singular to avoid running afoul of `no-dot-config-targets`.
1798 PHONY += rustdoc
1799 rustdoc: prepare
1800 $(Q)$(MAKE) $(build)=rust $@
1802 # Testing target
1803 PHONY += rusttest
1804 rusttest: prepare
1805 $(Q)$(MAKE) $(build)=rust $@
1807 # Formatting targets
1808 PHONY += rustfmt rustfmtcheck
1810 rustfmt:
1811 $(Q)find $(srctree) $(RCS_FIND_IGNORE) \
1812 -type f -a -name '*.rs' -a ! -name '*generated*' -print \
1813 | xargs $(RUSTFMT) $(rustfmt_flags)
1815 rustfmtcheck: rustfmt_flags = --check
1816 rustfmtcheck: rustfmt
1818 # Misc
1819 # ---------------------------------------------------------------------------
1821 PHONY += misc-check
1822 misc-check:
1823 $(Q)$(srctree)/scripts/misc-check
1825 all: misc-check
1827 PHONY += scripts_gdb
1828 scripts_gdb: prepare0
1829 $(Q)$(MAKE) $(build)=scripts/gdb
1830 $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1832 ifdef CONFIG_GDB_SCRIPTS
1833 all: scripts_gdb
1834 endif
1836 else # KBUILD_EXTMOD
1838 filechk_kernel.release = echo $(KERNELRELEASE)
1841 # External module support.
1842 # When building external modules the kernel used as basis is considered
1843 # read-only, and no consistency checks are made and the make
1844 # system is not used on the basis kernel. If updates are required
1845 # in the basis kernel ordinary make commands (without M=...) must be used.
1847 # We are always building only modules.
1848 KBUILD_BUILTIN :=
1849 KBUILD_MODULES := 1
1851 build-dir := .
1853 clean-dirs := .
1854 clean: private rm-files := Module.symvers modules.nsdeps compile_commands.json
1856 PHONY += prepare
1857 # now expand this into a simple variable to reduce the cost of shell evaluations
1858 prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT)
1859 prepare:
1860 @if [ "$(CC_VERSION_TEXT)" != "$(CONFIG_CC_VERSION_TEXT)" ]; then \
1861 echo >&2 "warning: the compiler differs from the one used to build the kernel"; \
1862 echo >&2 " The kernel was built by: $(CONFIG_CC_VERSION_TEXT)"; \
1863 echo >&2 " You are using: $(CC_VERSION_TEXT)"; \
1866 PHONY += help
1867 help:
1868 @echo ' Building external modules.'
1869 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1870 @echo ''
1871 @echo ' modules - default target, build the module(s)'
1872 @echo ' modules_install - install the module'
1873 @echo ' clean - remove generated files in module directory only'
1874 @echo ' rust-analyzer - generate rust-project.json rust-analyzer support file'
1875 @echo ''
1877 ifndef CONFIG_MODULES
1878 modules modules_install: __external_modules_error
1879 __external_modules_error:
1880 @echo >&2 '***'
1881 @echo >&2 '*** The present kernel disabled CONFIG_MODULES.'
1882 @echo >&2 '*** You cannot build or install external modules.'
1883 @echo >&2 '***'
1884 @false
1885 endif
1887 endif # KBUILD_EXTMOD
1889 # ---------------------------------------------------------------------------
1890 # Modules
1892 PHONY += modules modules_install modules_sign modules_prepare
1894 modules_install:
1895 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst \
1896 sign-only=$(if $(filter modules_install,$(MAKECMDGOALS)),,y)
1898 ifeq ($(CONFIG_MODULE_SIG),y)
1899 # modules_sign is a subset of modules_install.
1900 # 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1901 modules_sign: modules_install
1903 else
1904 modules_sign:
1905 @echo >&2 '***'
1906 @echo >&2 '*** CONFIG_MODULE_SIG is disabled. You cannot sign modules.'
1907 @echo >&2 '***'
1908 @false
1909 endif
1911 ifdef CONFIG_MODULES
1913 modules.order: $(build-dir)
1916 # KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
1917 # This is solely useful to speed up test compiles.
1918 modules: modpost
1919 ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1920 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1921 endif
1923 PHONY += modules_check
1924 modules_check: modules.order
1925 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1927 else # CONFIG_MODULES
1929 modules:
1932 KBUILD_MODULES :=
1934 endif # CONFIG_MODULES
1936 PHONY += modpost
1937 modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \
1938 $(if $(KBUILD_MODULES), modules_check)
1939 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1941 # Single targets
1942 # ---------------------------------------------------------------------------
1943 # To build individual files in subdirectories, you can do like this:
1945 # make foo/bar/baz.s
1947 # The supported suffixes for single-target are listed in 'single-targets'
1949 # To build only under specific subdirectories, you can do like this:
1951 # make foo/bar/baz/
1953 ifdef single-build
1955 # .ko is special because modpost is needed
1956 single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1957 single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \
1958 $(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko)))
1960 $(single-ko): single_modules
1962 $(single-no-ko): $(build-dir)
1965 # Remove modules.order when done because it is not the real one.
1966 PHONY += single_modules
1967 single_modules: $(single-no-ko) modules_prepare
1968 $(Q){ $(foreach m, $(single-ko), echo $(m:%.ko=%.o);) } > modules.order
1969 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1970 ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1971 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1972 endif
1973 $(Q)rm -f modules.order
1975 single-goals := $(addprefix $(build-dir)/, $(single-no-ko))
1977 KBUILD_MODULES := 1
1979 endif
1981 prepare: outputmakefile
1983 # Preset locale variables to speed up the build process. Limit locale
1984 # tweaks to this spot to avoid wrong language settings when running
1985 # make menuconfig etc.
1986 # Error messages still appears in the original language
1987 PHONY += $(build-dir)
1988 $(build-dir): prepare
1989 $(Q)$(MAKE) $(build)=$@ need-builtin=1 need-modorder=1 $(single-goals)
1991 clean-dirs := $(addprefix _clean_, $(clean-dirs))
1992 PHONY += $(clean-dirs) clean
1993 $(clean-dirs):
1994 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1996 clean: $(clean-dirs)
1997 $(call cmd,rmfiles)
1998 @find . $(RCS_FIND_IGNORE) \
1999 \( -name '*.[aios]' -o -name '*.rsi' -o -name '*.ko' -o -name '.*.cmd' \
2000 -o -name '*.ko.*' \
2001 -o -name '*.dtb' -o -name '*.dtbo' \
2002 -o -name '*.dtb.S' -o -name '*.dtbo.S' \
2003 -o -name '*.dt.yaml' -o -name 'dtbs-list' \
2004 -o -name '*.dwo' -o -name '*.lst' \
2005 -o -name '*.su' -o -name '*.mod' \
2006 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
2007 -o -name '*.lex.c' -o -name '*.tab.[ch]' \
2008 -o -name '*.asn1.[ch]' \
2009 -o -name '*.symtypes' -o -name 'modules.order' \
2010 -o -name '*.c.[012]*.*' \
2011 -o -name '*.ll' \
2012 -o -name '*.gcno' \
2013 \) -type f -print \
2014 -o -name '.tmp_*' -print \
2015 | xargs rm -rf
2017 # Generate tags for editors
2018 # ---------------------------------------------------------------------------
2019 quiet_cmd_tags = GEN $@
2020 cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
2022 tags TAGS cscope gtags: FORCE
2023 $(call cmd,tags)
2025 # Generate rust-project.json (a file that describes the structure of non-Cargo
2026 # Rust projects) for rust-analyzer (an implementation of the Language Server
2027 # Protocol).
2028 PHONY += rust-analyzer
2029 rust-analyzer:
2030 +$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh
2031 ifdef KBUILD_EXTMOD
2032 # FIXME: external modules must not descend into a sub-directory of the kernel
2033 $(Q)$(MAKE) $(build)=$(objtree)/rust src=$(srctree)/rust $@
2034 else
2035 $(Q)$(MAKE) $(build)=rust $@
2036 endif
2038 # Script to generate missing namespace dependencies
2039 # ---------------------------------------------------------------------------
2041 PHONY += nsdeps
2042 nsdeps: export KBUILD_NSDEPS=1
2043 nsdeps: modules
2044 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
2046 # Clang Tooling
2047 # ---------------------------------------------------------------------------
2049 quiet_cmd_gen_compile_commands = GEN $@
2050 cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
2052 compile_commands.json: $(srctree)/scripts/clang-tools/gen_compile_commands.py \
2053 $(if $(KBUILD_EXTMOD),, vmlinux.a $(KBUILD_VMLINUX_LIBS)) \
2054 $(if $(CONFIG_MODULES), modules.order) FORCE
2055 $(call if_changed,gen_compile_commands)
2057 targets += compile_commands.json
2059 PHONY += clang-tidy clang-analyzer
2061 ifdef CONFIG_CC_IS_CLANG
2062 quiet_cmd_clang_tools = CHECK $<
2063 cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
2065 clang-tidy clang-analyzer: compile_commands.json
2066 $(call cmd,clang_tools)
2067 else
2068 clang-tidy clang-analyzer:
2069 @echo "$@ requires CC=clang" >&2
2070 @false
2071 endif
2073 # Scripts to check various things for consistency
2074 # ---------------------------------------------------------------------------
2076 PHONY += includecheck versioncheck coccicheck
2078 includecheck:
2079 find $(srctree)/* $(RCS_FIND_IGNORE) \
2080 -name '*.[hcS]' -type f -print | sort \
2081 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
2083 versioncheck:
2084 find $(srctree)/* $(RCS_FIND_IGNORE) \
2085 -name '*.[hcS]' -type f -print | sort \
2086 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
2088 coccicheck:
2089 $(Q)$(BASH) $(srctree)/scripts/$@
2091 PHONY += checkstack kernelrelease kernelversion image_name
2093 # UML needs a little special treatment here. It wants to use the host
2094 # toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
2095 # else wants $(ARCH), including people doing cross-builds, which means
2096 # that $(SUBARCH) doesn't work here.
2097 ifeq ($(ARCH), um)
2098 CHECKSTACK_ARCH := $(SUBARCH)
2099 else
2100 CHECKSTACK_ARCH := $(ARCH)
2101 endif
2102 MINSTACKSIZE ?= 100
2103 checkstack:
2104 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
2105 $(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH) $(MINSTACKSIZE)
2107 kernelrelease:
2108 @$(filechk_kernel.release)
2110 kernelversion:
2111 @echo $(KERNELVERSION)
2113 image_name:
2114 @echo $(KBUILD_IMAGE)
2116 PHONY += run-command
2117 run-command:
2118 $(Q)$(KBUILD_RUN_COMMAND)
2120 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
2121 cmd_rmfiles = rm -rf $(rm-files)
2123 # read saved command lines for existing targets
2124 existing-targets := $(wildcard $(sort $(targets)))
2126 -include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
2128 endif # config-build
2129 endif # mixed-build
2130 endif # need-sub-make
2132 PHONY += FORCE
2133 FORCE:
2135 # Declare the contents of the PHONY variable as phony. We keep that
2136 # information in a variable so we can use it in if_changed and friends.
2137 .PHONY: $(PHONY)