xref: /linux/Makefile (revision ab52c59103002b49f2455371e4b9c56ba3ef1781)
1# SPDX-License-Identifier: GPL-2.0
2VERSION = 6
3PATCHLEVEL = 10
4SUBLEVEL = 0
5EXTRAVERSION = -rc1
6NAME = Baby Opossum Posse
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
14ifeq ($(filter undefine,$(.FEATURES)),)
15$(error GNU Make >= 3.82 is required. Your Make version is $(MAKE_VERSION))
16endif
17
18$(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
22PHONY := __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
41this-makefile := $(lastword $(MAKEFILE_LIST))
42abs_srctree := $(realpath $(dir $(this-makefile)))
43abs_objtree := $(CURDIR)
44
45ifneq ($(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)
49MAKEFLAGS += -rR
50
51# Avoid funny character set dependencies
52unexport LC_ALL
53LC_COLLATE=C
54LC_NUMERIC=C
55export LC_COLLATE LC_NUMERIC
56
57# Avoid interference with shell env settings
58unexport 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) $(build)=scripts/basic
75#
76# If KBUILD_VERBOSE contains 1, the whole command is echoed.
77# If KBUILD_VERBOSE contains 2, the reason for rebuilding is printed.
78#
79# To put more focus on warnings, be less verbose as default
80# Use 'make V=1' to see the full commands
81
82ifeq ("$(origin V)", "command line")
83  KBUILD_VERBOSE = $(V)
84endif
85
86quiet = quiet_
87Q = @
88
89ifneq ($(findstring 1, $(KBUILD_VERBOSE)),)
90  quiet =
91  Q =
92endif
93
94# If the user is running make -s (silent mode), suppress echoing of
95# commands
96# make-4.0 (and later) keep single letter options in the 1st word of MAKEFLAGS.
97
98ifeq ($(filter 3.%,$(MAKE_VERSION)),)
99short-opts := $(firstword -$(MAKEFLAGS))
100else
101short-opts := $(filter-out --%,$(MAKEFLAGS))
102endif
103
104ifneq ($(findstring s,$(short-opts)),)
105quiet=silent_
106override KBUILD_VERBOSE :=
107endif
108
109export 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
121ifeq ("$(origin C)", "command line")
122  KBUILD_CHECKSRC = $(C)
123endif
124ifndef KBUILD_CHECKSRC
125  KBUILD_CHECKSRC = 0
126endif
127
128export KBUILD_CHECKSRC
129
130# Enable "clippy" (a linter) as part of the Rust compilation.
131#
132# Use 'make CLIPPY=1' to enable it.
133ifeq ("$(origin CLIPPY)", "command line")
134  KBUILD_CLIPPY := $(CLIPPY)
135endif
136
137export KBUILD_CLIPPY
138
139# Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
140# directory of external module to build. Setting M= takes precedence.
141ifeq ("$(origin M)", "command line")
142  KBUILD_EXTMOD := $(M)
143endif
144
145$(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
152ifneq ($(filter %/, $(KBUILD_EXTMOD)),)
153KBUILD_EXTMOD := $(shell dirname $(KBUILD_EXTMOD).)
154endif
155
156export KBUILD_EXTMOD
157
158# backward compatibility
159KBUILD_EXTRA_WARN ?= $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)
160
161ifeq ("$(origin W)", "command line")
162  KBUILD_EXTRA_WARN := $(W)
163endif
164
165export KBUILD_EXTRA_WARN
166
167# Kbuild will save output files in the current working directory.
168# This does not need to match to the root of the kernel source tree.
169#
170# For example, you can do this:
171#
172#  cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
173#
174# If you want to save output files in a different location, there are
175# two syntaxes to specify it.
176#
177# 1) O=
178# Use "make O=dir/to/store/output/files/"
179#
180# 2) Set KBUILD_OUTPUT
181# Set the environment variable KBUILD_OUTPUT to point to the output directory.
182# export KBUILD_OUTPUT=dir/to/store/output/files/; make
183#
184# The O= assignment takes precedence over the KBUILD_OUTPUT environment
185# variable.
186
187# Do we want to change the working directory?
188ifeq ("$(origin O)", "command line")
189  KBUILD_OUTPUT := $(O)
190endif
191
192ifneq ($(KBUILD_OUTPUT),)
193# $(realpath ...) gets empty if the path does not exist. Run 'mkdir -p' first.
194$(shell mkdir -p "$(KBUILD_OUTPUT)")
195# $(realpath ...) resolves symlinks
196abs_objtree := $(realpath $(KBUILD_OUTPUT))
197$(if $(abs_objtree),,$(error failed to create output directory "$(KBUILD_OUTPUT)"))
198endif # ifneq ($(KBUILD_OUTPUT),)
199
200ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
201$(error source directory cannot contain spaces or colons)
202endif
203
204ifneq ($(filter 3.%,$(MAKE_VERSION)),)
205# 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
206# We need to invoke sub-make to avoid implicit rules in the top Makefile.
207need-sub-make := 1
208# Cancel implicit rules for this Makefile.
209$(this-makefile): ;
210endif
211
212export sub_make_done := 1
213
214endif # sub_make_done
215
216ifeq ($(abs_objtree),$(CURDIR))
217# Suppress "Entering directory ..." if we are at the final work directory.
218no-print-directory := --no-print-directory
219else
220# Recursion to show "Entering directory ..."
221need-sub-make := 1
222endif
223
224ifeq ($(filter --no-print-directory, $(MAKEFLAGS)),)
225# If --no-print-directory is unset, recurse once again to set it.
226# You may end up recursing into __sub-make twice. This is needed due to the
227# behavior change in GNU Make 4.4.1.
228need-sub-make := 1
229endif
230
231ifeq ($(need-sub-make),1)
232
233PHONY += $(MAKECMDGOALS) __sub-make
234
235$(filter-out $(this-makefile), $(MAKECMDGOALS)) __all: __sub-make
236	@:
237
238# Invoke a second make in the output directory, passing relevant variables
239__sub-make:
240	$(Q)$(MAKE) $(no-print-directory) -C $(abs_objtree) \
241	-f $(abs_srctree)/Makefile $(MAKECMDGOALS)
242
243else # need-sub-make
244
245# We process the rest of the Makefile if this is the final invocation of make
246
247ifeq ($(abs_srctree),$(abs_objtree))
248        # building in the source tree
249        srctree := .
250	building_out_of_srctree :=
251else
252        ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
253                # building in a subdirectory of the source tree
254                srctree := ..
255        else
256                srctree := $(abs_srctree)
257        endif
258	building_out_of_srctree := 1
259endif
260
261ifneq ($(KBUILD_ABS_SRCTREE),)
262srctree := $(abs_srctree)
263endif
264
265objtree		:= .
266
267VPATH		:=
268
269ifeq ($(KBUILD_EXTMOD),)
270ifdef building_out_of_srctree
271VPATH		:= $(srctree)
272endif
273endif
274
275export building_out_of_srctree srctree objtree VPATH
276
277# To make sure we do not include .config for any of the *config targets
278# catch them early, and hand them over to scripts/kconfig/Makefile
279# It is allowed to specify more targets when calling make, including
280# mixing *config targets and build targets.
281# For example 'make oldconfig all'.
282# Detect when mixed targets is specified, and make a second invocation
283# of make so .config is not included in this case either (for *config).
284
285version_h := include/generated/uapi/linux/version.h
286
287clean-targets := %clean mrproper cleandocs
288no-dot-config-targets := $(clean-targets) \
289			 cscope gtags TAGS tags help% %docs check% coccicheck \
290			 $(version_h) headers headers_% archheaders archscripts \
291			 %asm-generic kernelversion %src-pkg dt_binding_check \
292			 outputmakefile rustavailable rustfmt rustfmtcheck
293no-sync-config-targets := $(no-dot-config-targets) %install modules_sign kernelrelease \
294			  image_name
295single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.rsi %.s %.symtypes %/
296
297config-build	:=
298mixed-build	:=
299need-config	:= 1
300may-sync-config	:= 1
301single-build	:=
302
303ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
304    ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
305        need-config :=
306    endif
307endif
308
309ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
310    ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
311        may-sync-config :=
312    endif
313endif
314
315need-compiler := $(may-sync-config)
316
317ifneq ($(KBUILD_EXTMOD),)
318    may-sync-config :=
319endif
320
321ifeq ($(KBUILD_EXTMOD),)
322    ifneq ($(filter %config,$(MAKECMDGOALS)),)
323        config-build := 1
324        ifneq ($(words $(MAKECMDGOALS)),1)
325            mixed-build := 1
326        endif
327    endif
328endif
329
330# We cannot build single targets and the others at the same time
331ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
332    single-build := 1
333    ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
334        mixed-build := 1
335    endif
336endif
337
338# For "make -j clean all", "make -j mrproper defconfig all", etc.
339ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
340    ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
341        mixed-build := 1
342    endif
343endif
344
345# install and modules_install need also be processed one by one
346ifneq ($(filter install,$(MAKECMDGOALS)),)
347    ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
348        mixed-build := 1
349    endif
350endif
351
352ifdef mixed-build
353# ===========================================================================
354# We're called with mixed targets (*config and build targets).
355# Handle them one by one.
356
357PHONY += $(MAKECMDGOALS) __build_one_by_one
358
359$(MAKECMDGOALS): __build_one_by_one
360	@:
361
362__build_one_by_one:
363	$(Q)set -e; \
364	for i in $(MAKECMDGOALS); do \
365		$(MAKE) -f $(srctree)/Makefile $$i; \
366	done
367
368else # !mixed-build
369
370include $(srctree)/scripts/Kbuild.include
371
372# Read KERNELRELEASE from include/config/kernel.release (if it exists)
373KERNELRELEASE = $(call read-file, include/config/kernel.release)
374KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
375export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
376
377include $(srctree)/scripts/subarch.include
378
379# Cross compiling and selecting different set of gcc/bin-utils
380# ---------------------------------------------------------------------------
381#
382# When performing cross compilation for other architectures ARCH shall be set
383# to the target architecture. (See arch/* for the possibilities).
384# ARCH can be set during invocation of make:
385# make ARCH=arm64
386# Another way is to have ARCH set in the environment.
387# The default ARCH is the host where make is executed.
388
389# CROSS_COMPILE specify the prefix used for all executables used
390# during compilation. Only gcc and related bin-utils executables
391# are prefixed with $(CROSS_COMPILE).
392# CROSS_COMPILE can be set on the command line
393# make CROSS_COMPILE=aarch64-linux-gnu-
394# Alternatively CROSS_COMPILE can be set in the environment.
395# Default value for CROSS_COMPILE is not to prefix executables
396# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
397ARCH		?= $(SUBARCH)
398
399# Architecture as present in compile.h
400UTS_MACHINE 	:= $(ARCH)
401SRCARCH 	:= $(ARCH)
402
403# Additional ARCH settings for x86
404ifeq ($(ARCH),i386)
405        SRCARCH := x86
406endif
407ifeq ($(ARCH),x86_64)
408        SRCARCH := x86
409endif
410
411# Additional ARCH settings for sparc
412ifeq ($(ARCH),sparc32)
413       SRCARCH := sparc
414endif
415ifeq ($(ARCH),sparc64)
416       SRCARCH := sparc
417endif
418
419# Additional ARCH settings for parisc
420ifeq ($(ARCH),parisc64)
421       SRCARCH := parisc
422endif
423
424export cross_compiling :=
425ifneq ($(SRCARCH),$(SUBARCH))
426cross_compiling := 1
427endif
428
429KCONFIG_CONFIG	?= .config
430export KCONFIG_CONFIG
431
432# SHELL used by kbuild
433CONFIG_SHELL := sh
434
435HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
436HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
437HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
438
439ifneq ($(LLVM),)
440ifneq ($(filter %/,$(LLVM)),)
441LLVM_PREFIX := $(LLVM)
442else ifneq ($(filter -%,$(LLVM)),)
443LLVM_SUFFIX := $(LLVM)
444endif
445
446HOSTCC	= $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
447HOSTCXX	= $(LLVM_PREFIX)clang++$(LLVM_SUFFIX)
448else
449HOSTCC	= gcc
450HOSTCXX	= g++
451endif
452HOSTRUSTC = rustc
453HOSTPKG_CONFIG	= pkg-config
454
455KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
456			 -O2 -fomit-frame-pointer -std=gnu11
457KBUILD_USERCFLAGS  := $(KBUILD_USERHOSTCFLAGS) $(USERCFLAGS)
458KBUILD_USERLDFLAGS := $(USERLDFLAGS)
459
460# These flags apply to all Rust code in the tree, including the kernel and
461# host programs.
462export rust_common_flags := --edition=2021 \
463			    -Zbinary_dep_depinfo=y \
464			    -Dunsafe_op_in_unsafe_fn -Drust_2018_idioms \
465			    -Dunreachable_pub -Dnon_ascii_idents \
466			    -Wmissing_docs \
467			    -Drustdoc::missing_crate_level_docs \
468			    -Dclippy::correctness -Dclippy::style \
469			    -Dclippy::suspicious -Dclippy::complexity \
470			    -Dclippy::perf \
471			    -Dclippy::let_unit_value -Dclippy::mut_mut \
472			    -Dclippy::needless_bitwise_bool \
473			    -Dclippy::needless_continue \
474			    -Dclippy::no_mangle_with_rust_abi \
475			    -Wclippy::dbg_macro
476
477KBUILD_HOSTCFLAGS   := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
478KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
479KBUILD_HOSTRUSTFLAGS := $(rust_common_flags) -O -Cstrip=debuginfo \
480			-Zallow-features= $(HOSTRUSTFLAGS)
481KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
482KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
483
484# Make variables (CC, etc...)
485CPP		= $(CC) -E
486ifneq ($(LLVM),)
487CC		= $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
488LD		= $(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX)
489AR		= $(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX)
490NM		= $(LLVM_PREFIX)llvm-nm$(LLVM_SUFFIX)
491OBJCOPY		= $(LLVM_PREFIX)llvm-objcopy$(LLVM_SUFFIX)
492OBJDUMP		= $(LLVM_PREFIX)llvm-objdump$(LLVM_SUFFIX)
493READELF		= $(LLVM_PREFIX)llvm-readelf$(LLVM_SUFFIX)
494STRIP		= $(LLVM_PREFIX)llvm-strip$(LLVM_SUFFIX)
495else
496CC		= $(CROSS_COMPILE)gcc
497LD		= $(CROSS_COMPILE)ld
498AR		= $(CROSS_COMPILE)ar
499NM		= $(CROSS_COMPILE)nm
500OBJCOPY		= $(CROSS_COMPILE)objcopy
501OBJDUMP		= $(CROSS_COMPILE)objdump
502READELF		= $(CROSS_COMPILE)readelf
503STRIP		= $(CROSS_COMPILE)strip
504endif
505RUSTC		= rustc
506RUSTDOC		= rustdoc
507RUSTFMT		= rustfmt
508CLIPPY_DRIVER	= clippy-driver
509BINDGEN		= bindgen
510CARGO		= cargo
511PAHOLE		= pahole
512RESOLVE_BTFIDS	= $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
513LEX		= flex
514YACC		= bison
515AWK		= awk
516INSTALLKERNEL  := installkernel
517PERL		= perl
518PYTHON3		= python3
519CHECK		= sparse
520BASH		= bash
521KGZIP		= gzip
522KBZIP2		= bzip2
523KLZOP		= lzop
524LZMA		= lzma
525LZ4		= lz4c
526XZ		= xz
527ZSTD		= zstd
528
529CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
530		  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
531NOSTDINC_FLAGS :=
532CFLAGS_MODULE   =
533RUSTFLAGS_MODULE =
534AFLAGS_MODULE   =
535LDFLAGS_MODULE  =
536CFLAGS_KERNEL	=
537RUSTFLAGS_KERNEL =
538AFLAGS_KERNEL	=
539LDFLAGS_vmlinux =
540
541# Use USERINCLUDE when you must reference the UAPI directories only.
542USERINCLUDE    := \
543		-I$(srctree)/arch/$(SRCARCH)/include/uapi \
544		-I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
545		-I$(srctree)/include/uapi \
546		-I$(objtree)/include/generated/uapi \
547                -include $(srctree)/include/linux/compiler-version.h \
548                -include $(srctree)/include/linux/kconfig.h
549
550# Use LINUXINCLUDE when you must reference the include/ directory.
551# Needed to be compatible with the O= option
552LINUXINCLUDE    := \
553		-I$(srctree)/arch/$(SRCARCH)/include \
554		-I$(objtree)/arch/$(SRCARCH)/include/generated \
555		$(if $(building_out_of_srctree),-I$(srctree)/include) \
556		-I$(objtree)/include \
557		$(USERINCLUDE)
558
559KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
560
561KBUILD_CFLAGS :=
562KBUILD_CFLAGS += -std=gnu11
563KBUILD_CFLAGS += -fshort-wchar
564KBUILD_CFLAGS += -funsigned-char
565KBUILD_CFLAGS += -fno-common
566KBUILD_CFLAGS += -fno-PIE
567KBUILD_CFLAGS += -fno-strict-aliasing
568
569KBUILD_CPPFLAGS := -D__KERNEL__
570KBUILD_RUSTFLAGS := $(rust_common_flags) \
571		    -Cpanic=abort -Cembed-bitcode=n -Clto=n \
572		    -Cforce-unwind-tables=n -Ccodegen-units=1 \
573		    -Csymbol-mangling-version=v0 \
574		    -Crelocation-model=static \
575		    -Zfunction-sections=n \
576		    -Dclippy::float_arithmetic
577
578KBUILD_AFLAGS_KERNEL :=
579KBUILD_CFLAGS_KERNEL :=
580KBUILD_RUSTFLAGS_KERNEL :=
581KBUILD_AFLAGS_MODULE  := -DMODULE
582KBUILD_CFLAGS_MODULE  := -DMODULE
583KBUILD_RUSTFLAGS_MODULE := --cfg MODULE
584KBUILD_LDFLAGS_MODULE :=
585KBUILD_LDFLAGS :=
586CLANG_FLAGS :=
587
588ifeq ($(KBUILD_CLIPPY),1)
589	RUSTC_OR_CLIPPY_QUIET := CLIPPY
590	RUSTC_OR_CLIPPY = $(CLIPPY_DRIVER)
591else
592	RUSTC_OR_CLIPPY_QUIET := RUSTC
593	RUSTC_OR_CLIPPY = $(RUSTC)
594endif
595
596ifdef RUST_LIB_SRC
597	export RUST_LIB_SRC
598endif
599
600# Allows the usage of unstable features in stable compilers.
601export RUSTC_BOOTSTRAP := 1
602
603export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG
604export RUSTC RUSTDOC RUSTFMT RUSTC_OR_CLIPPY_QUIET RUSTC_OR_CLIPPY BINDGEN CARGO
605export HOSTRUSTC KBUILD_HOSTRUSTFLAGS
606export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
607export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
608export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
609export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
610export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS
611
612export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
613export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
614export KBUILD_RUSTFLAGS RUSTFLAGS_KERNEL RUSTFLAGS_MODULE
615export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
616export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_RUSTFLAGS_MODULE KBUILD_LDFLAGS_MODULE
617export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL KBUILD_RUSTFLAGS_KERNEL
618
619# Files to ignore in find ... statements
620
621export 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
625# ===========================================================================
626# Rules shared between *config targets and build targets
627
628# Basic helpers built in scripts/basic/
629PHONY += scripts_basic
630scripts_basic:
631	$(Q)$(MAKE) $(build)=scripts/basic
632
633PHONY += outputmakefile
634ifdef building_out_of_srctree
635# Before starting out-of-tree build, make sure the source tree is clean.
636# outputmakefile generates a Makefile in the output directory, if using a
637# separate output directory. This allows convenient use of make in the
638# output directory.
639# At the same time when output Makefile generated, generate .gitignore to
640# ignore whole output directory
641
642quiet_cmd_makefile = GEN     Makefile
643      cmd_makefile = { \
644	echo "\# Automatically generated by $(srctree)/Makefile: don't edit"; \
645	echo "include $(srctree)/Makefile"; \
646	} > Makefile
647
648outputmakefile:
649	@if [ -f $(srctree)/.config -o \
650		 -d $(srctree)/include/config -o \
651		 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
652		echo >&2 "***"; \
653		echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
654		echo >&2 "*** in $(abs_srctree)";\
655		echo >&2 "***"; \
656		false; \
657	fi
658	$(Q)ln -fsn $(srctree) source
659	$(call cmd,makefile)
660	$(Q)test -e .gitignore || \
661	{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
662endif
663
664# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
665# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
666# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
667# and from include/config/auto.conf.cmd to detect the compiler upgrade.
668CC_VERSION_TEXT = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1))
669
670ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
671include $(srctree)/scripts/Makefile.clang
672endif
673
674# Include this also for config targets because some architectures need
675# cc-cross-prefix to determine CROSS_COMPILE.
676ifdef need-compiler
677include $(srctree)/scripts/Makefile.compiler
678endif
679
680ifdef config-build
681# ===========================================================================
682# *config targets only - make sure prerequisites are updated, and descend
683# in scripts/kconfig to make the *config target
684
685# Read arch-specific Makefile to set KBUILD_DEFCONFIG as needed.
686# KBUILD_DEFCONFIG may point out an alternative default configuration
687# used for 'make defconfig'
688include $(srctree)/arch/$(SRCARCH)/Makefile
689export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
690
691config: outputmakefile scripts_basic FORCE
692	$(Q)$(MAKE) $(build)=scripts/kconfig $@
693
694%config: outputmakefile scripts_basic FORCE
695	$(Q)$(MAKE) $(build)=scripts/kconfig $@
696
697else #!config-build
698# ===========================================================================
699# Build targets only - this includes vmlinux, arch-specific targets, clean
700# targets and others. In general all targets except *config targets.
701
702# If building an external module we do not care about the all: rule
703# but instead __all depend on modules
704PHONY += all
705ifeq ($(KBUILD_EXTMOD),)
706__all: all
707else
708__all: modules
709endif
710
711targets :=
712
713# Decide whether to build built-in, modular, or both.
714# Normally, just do built-in.
715
716KBUILD_MODULES :=
717KBUILD_BUILTIN := 1
718
719# If we have only "make modules", don't compile built-in objects.
720ifeq ($(MAKECMDGOALS),modules)
721  KBUILD_BUILTIN :=
722endif
723
724# If we have "make <whatever> modules", compile modules
725# in addition to whatever we do anyway.
726# Just "make" or "make all" shall build modules as well
727
728ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
729  KBUILD_MODULES := 1
730endif
731
732ifeq ($(MAKECMDGOALS),)
733  KBUILD_MODULES := 1
734endif
735
736export KBUILD_MODULES KBUILD_BUILTIN
737
738ifdef need-config
739include include/config/auto.conf
740endif
741
742ifeq ($(KBUILD_EXTMOD),)
743# Objects we will link into vmlinux / subdirs we need to visit
744core-y		:=
745drivers-y	:=
746libs-y		:= lib/
747endif # KBUILD_EXTMOD
748
749# The all: target is the default when no target is given on the
750# command line.
751# This allow a user to issue only 'make' to build a kernel including modules
752# Defaults to vmlinux, but the arch makefile usually adds further targets
753all: vmlinux
754
755CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage
756ifdef CONFIG_CC_IS_GCC
757CFLAGS_GCOV	+= -fno-tree-loop-im
758endif
759export CFLAGS_GCOV
760
761# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
762ifdef CONFIG_FUNCTION_TRACER
763  CC_FLAGS_FTRACE := -pg
764endif
765
766include $(srctree)/arch/$(SRCARCH)/Makefile
767
768ifdef need-config
769ifdef may-sync-config
770# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
771# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
772# because some architectures define CROSS_COMPILE there.
773include include/config/auto.conf.cmd
774
775$(KCONFIG_CONFIG):
776	@echo >&2 '***'
777	@echo >&2 '*** Configuration file "$@" not found!'
778	@echo >&2 '***'
779	@echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
780	@echo >&2 '*** "make menuconfig" or "make xconfig").'
781	@echo >&2 '***'
782	@/bin/false
783
784# The actual configuration files used during the build are stored in
785# include/generated/ and include/config/. Update them if .config is newer than
786# include/config/auto.conf (which mirrors .config).
787#
788# This exploits the 'multi-target pattern rule' trick.
789# The syncconfig should be executed only once to make all the targets.
790# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
791#
792# Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
793# so you cannot notice that Kconfig is waiting for the user input.
794%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h %/generated/rustc_cfg: $(KCONFIG_CONFIG)
795	$(Q)$(kecho) "  SYNC    $@"
796	$(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
797else # !may-sync-config
798# External modules and some install targets need include/generated/autoconf.h
799# and include/config/auto.conf but do not care if they are up-to-date.
800# Use auto.conf to trigger the test
801PHONY += include/config/auto.conf
802
803include/config/auto.conf:
804	@test -e include/generated/autoconf.h -a -e $@ || (		\
805	echo >&2;							\
806	echo >&2 "  ERROR: Kernel configuration is invalid.";		\
807	echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
808	echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";	\
809	echo >&2 ;							\
810	/bin/false)
811
812endif # may-sync-config
813endif # need-config
814
815KBUILD_CFLAGS	+= -fno-delete-null-pointer-checks
816
817ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
818KBUILD_CFLAGS += -O2
819KBUILD_RUSTFLAGS += -Copt-level=2
820else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
821KBUILD_CFLAGS += -Os
822KBUILD_RUSTFLAGS += -Copt-level=s
823endif
824
825# Always set `debug-assertions` and `overflow-checks` because their default
826# depends on `opt-level` and `debug-assertions`, respectively.
827KBUILD_RUSTFLAGS += -Cdebug-assertions=$(if $(CONFIG_RUST_DEBUG_ASSERTIONS),y,n)
828KBUILD_RUSTFLAGS += -Coverflow-checks=$(if $(CONFIG_RUST_OVERFLOW_CHECKS),y,n)
829
830# Tell gcc to never replace conditional load with a non-conditional one
831ifdef CONFIG_CC_IS_GCC
832# gcc-10 renamed --param=allow-store-data-races=0 to
833# -fno-allow-store-data-races.
834KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
835KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
836endif
837
838ifdef CONFIG_READABLE_ASM
839# Disable optimizations that make assembler listings hard to read.
840# reorder blocks reorders the control in the function
841# ipa clone creates specialized cloned functions
842# partial inlining inlines only parts of functions
843KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
844endif
845
846stackp-flags-y                                    := -fno-stack-protector
847stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
848stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
849
850KBUILD_CFLAGS += $(stackp-flags-y)
851
852KBUILD_RUSTFLAGS-$(CONFIG_WERROR) += -Dwarnings
853KBUILD_RUSTFLAGS += $(KBUILD_RUSTFLAGS-y)
854
855ifdef CONFIG_FRAME_POINTER
856KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
857KBUILD_RUSTFLAGS += -Cforce-frame-pointers=y
858else
859# Some targets (ARM with Thumb2, for example), can't be built with frame
860# pointers.  For those, we don't have FUNCTION_TRACER automatically
861# select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
862# incompatible with -fomit-frame-pointer with current GCC, so we don't use
863# -fomit-frame-pointer with FUNCTION_TRACER.
864# In the Rust target specification, "frame-pointer" is set explicitly
865# to "may-omit".
866ifndef CONFIG_FUNCTION_TRACER
867KBUILD_CFLAGS	+= -fomit-frame-pointer
868endif
869endif
870
871# Initialize all stack variables with a 0xAA pattern.
872ifdef CONFIG_INIT_STACK_ALL_PATTERN
873KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
874endif
875
876# Initialize all stack variables with a zero value.
877ifdef CONFIG_INIT_STACK_ALL_ZERO
878KBUILD_CFLAGS	+= -ftrivial-auto-var-init=zero
879ifdef CONFIG_CC_HAS_AUTO_VAR_INIT_ZERO_ENABLER
880# https://github.com/llvm/llvm-project/issues/44842
881CC_AUTO_VAR_INIT_ZERO_ENABLER := -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
882export CC_AUTO_VAR_INIT_ZERO_ENABLER
883KBUILD_CFLAGS	+= $(CC_AUTO_VAR_INIT_ZERO_ENABLER)
884endif
885endif
886
887# While VLAs have been removed, GCC produces unreachable stack probes
888# for the randomize_kstack_offset feature. Disable it for all compilers.
889KBUILD_CFLAGS	+= $(call cc-option, -fno-stack-clash-protection)
890
891# Clear used registers at func exit (to reduce data lifetime and ROP gadgets).
892ifdef CONFIG_ZERO_CALL_USED_REGS
893KBUILD_CFLAGS	+= -fzero-call-used-regs=used-gpr
894endif
895
896ifdef CONFIG_FUNCTION_TRACER
897ifdef CONFIG_FTRACE_MCOUNT_USE_CC
898  CC_FLAGS_FTRACE	+= -mrecord-mcount
899  ifdef CONFIG_HAVE_NOP_MCOUNT
900    ifeq ($(call cc-option-yn, -mnop-mcount),y)
901      CC_FLAGS_FTRACE	+= -mnop-mcount
902      CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
903    endif
904  endif
905endif
906ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
907  ifdef CONFIG_HAVE_OBJTOOL_NOP_MCOUNT
908    CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
909  endif
910endif
911ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
912  ifdef CONFIG_HAVE_C_RECORDMCOUNT
913    BUILD_C_RECORDMCOUNT := y
914    export BUILD_C_RECORDMCOUNT
915  endif
916endif
917ifdef CONFIG_HAVE_FENTRY
918  # s390-linux-gnu-gcc did not support -mfentry until gcc-9.
919  ifeq ($(call cc-option-yn, -mfentry),y)
920    CC_FLAGS_FTRACE	+= -mfentry
921    CC_FLAGS_USING	+= -DCC_USING_FENTRY
922  endif
923endif
924export CC_FLAGS_FTRACE
925KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
926KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
927endif
928
929# We trigger additional mismatches with less inlining
930ifdef CONFIG_DEBUG_SECTION_MISMATCH
931KBUILD_CFLAGS += -fno-inline-functions-called-once
932endif
933
934# `rustc`'s `-Zfunction-sections` applies to data too (as of 1.59.0).
935ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
936KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
937KBUILD_RUSTFLAGS_KERNEL += -Zfunction-sections=y
938LDFLAGS_vmlinux += --gc-sections
939endif
940
941ifdef CONFIG_SHADOW_CALL_STACK
942ifndef CONFIG_DYNAMIC_SCS
943CC_FLAGS_SCS	:= -fsanitize=shadow-call-stack
944KBUILD_CFLAGS	+= $(CC_FLAGS_SCS)
945endif
946export CC_FLAGS_SCS
947endif
948
949ifdef CONFIG_LTO_CLANG
950ifdef CONFIG_LTO_CLANG_THIN
951CC_FLAGS_LTO	:= -flto=thin -fsplit-lto-unit
952else
953CC_FLAGS_LTO	:= -flto
954endif
955CC_FLAGS_LTO	+= -fvisibility=hidden
956
957# Limit inlining across translation units to reduce binary size
958KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
959endif
960
961ifdef CONFIG_LTO
962KBUILD_CFLAGS	+= -fno-lto $(CC_FLAGS_LTO)
963KBUILD_AFLAGS	+= -fno-lto
964export CC_FLAGS_LTO
965endif
966
967ifdef CONFIG_CFI_CLANG
968CC_FLAGS_CFI	:= -fsanitize=kcfi
969KBUILD_CFLAGS	+= $(CC_FLAGS_CFI)
970export CC_FLAGS_CFI
971endif
972
973# Architectures can define flags to add/remove for floating-point support
974CC_FLAGS_FPU	+= -D_LINUX_FPU_COMPILATION_UNIT
975export CC_FLAGS_FPU
976export CC_FLAGS_NO_FPU
977
978ifneq ($(CONFIG_FUNCTION_ALIGNMENT),0)
979# Set the minimal function alignment. Use the newer GCC option
980# -fmin-function-alignment if it is available, or fall back to -falign-funtions.
981# See also CONFIG_CC_HAS_SANE_FUNCTION_ALIGNMENT.
982ifdef CONFIG_CC_HAS_MIN_FUNCTION_ALIGNMENT
983KBUILD_CFLAGS += -fmin-function-alignment=$(CONFIG_FUNCTION_ALIGNMENT)
984else
985KBUILD_CFLAGS += -falign-functions=$(CONFIG_FUNCTION_ALIGNMENT)
986endif
987endif
988
989# arch Makefile may override CC so keep this after arch Makefile is included
990NOSTDINC_FLAGS += -nostdinc
991
992# To gain proper coverage for CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE,
993# the kernel uses only C99 flexible arrays for dynamically sized trailing
994# arrays. Enforce this for everything that may examine structure sizes and
995# perform bounds checking.
996KBUILD_CFLAGS += $(call cc-option, -fstrict-flex-arrays=3)
997
998#Currently, disable -Wstringop-overflow for GCC 11, globally.
999KBUILD_CFLAGS-$(CONFIG_CC_NO_STRINGOP_OVERFLOW) += $(call cc-option, -Wno-stringop-overflow)
1000KBUILD_CFLAGS-$(CONFIG_CC_STRINGOP_OVERFLOW) += $(call cc-option, -Wstringop-overflow)
1001
1002# disable invalid "can't wrap" optimizations for signed / pointers
1003KBUILD_CFLAGS	+= -fno-strict-overflow
1004
1005# Make sure -fstack-check isn't enabled (like gentoo apparently did)
1006KBUILD_CFLAGS  += -fno-stack-check
1007
1008# conserve stack if available
1009ifdef CONFIG_CC_IS_GCC
1010KBUILD_CFLAGS   += -fconserve-stack
1011endif
1012
1013# change __FILE__ to the relative path from the srctree
1014KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
1015
1016# include additional Makefiles when needed
1017include-y			:= scripts/Makefile.extrawarn
1018include-$(CONFIG_DEBUG_INFO)	+= scripts/Makefile.debug
1019include-$(CONFIG_DEBUG_INFO_BTF)+= scripts/Makefile.btf
1020include-$(CONFIG_KASAN)		+= scripts/Makefile.kasan
1021include-$(CONFIG_KCSAN)		+= scripts/Makefile.kcsan
1022include-$(CONFIG_KMSAN)		+= scripts/Makefile.kmsan
1023include-$(CONFIG_UBSAN)		+= scripts/Makefile.ubsan
1024include-$(CONFIG_KCOV)		+= scripts/Makefile.kcov
1025include-$(CONFIG_RANDSTRUCT)	+= scripts/Makefile.randstruct
1026include-$(CONFIG_GCC_PLUGINS)	+= scripts/Makefile.gcc-plugins
1027
1028include $(addprefix $(srctree)/, $(include-y))
1029
1030# scripts/Makefile.gcc-plugins is intentionally included last.
1031# Do not add $(call cc-option,...) below this line. When you build the kernel
1032# from the clean source tree, the GCC plugins do not exist at this point.
1033
1034# Add user supplied CPPFLAGS, AFLAGS, CFLAGS and RUSTFLAGS as the last assignments
1035KBUILD_CPPFLAGS += $(KCPPFLAGS)
1036KBUILD_AFLAGS   += $(KAFLAGS)
1037KBUILD_CFLAGS   += $(KCFLAGS)
1038KBUILD_RUSTFLAGS += $(KRUSTFLAGS)
1039
1040KBUILD_LDFLAGS_MODULE += --build-id=sha1
1041LDFLAGS_vmlinux += --build-id=sha1
1042
1043KBUILD_LDFLAGS	+= -z noexecstack
1044ifeq ($(CONFIG_LD_IS_BFD),y)
1045KBUILD_LDFLAGS	+= $(call ld-option,--no-warn-rwx-segments)
1046endif
1047
1048ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1049LDFLAGS_vmlinux	+= -X
1050endif
1051
1052ifeq ($(CONFIG_RELR),y)
1053# ld.lld before 15 did not support -z pack-relative-relocs.
1054LDFLAGS_vmlinux	+= $(call ld-option,--pack-dyn-relocs=relr,-z pack-relative-relocs)
1055endif
1056
1057# We never want expected sections to be placed heuristically by the
1058# linker. All sections should be explicitly named in the linker script.
1059ifdef CONFIG_LD_ORPHAN_WARN
1060LDFLAGS_vmlinux += --orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL)
1061endif
1062
1063# Align the bit size of userspace programs with the kernel
1064KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1065KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1066
1067# make the checker run with the right architecture
1068CHECKFLAGS += --arch=$(ARCH)
1069
1070# insure the checker run with the right endianness
1071CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1072
1073# the checker needs the correct machine size
1074CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1075
1076# Default kernel image to build when no specific target is given.
1077# KBUILD_IMAGE may be overruled on the command line or
1078# set in the environment
1079# Also any assignments in arch/$(ARCH)/Makefile take precedence over
1080# this default value
1081export KBUILD_IMAGE ?= vmlinux
1082
1083#
1084# INSTALL_PATH specifies where to place the updated kernel and system map
1085# images. Default is /boot, but you can set it to other values
1086export	INSTALL_PATH ?= /boot
1087
1088#
1089# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1090# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1091# an argument if needed. Otherwise it defaults to the kernel install path
1092#
1093export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1094
1095#
1096# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1097# relocations required by build roots.  This is not defined in the
1098# makefile but the argument can be passed to make if needed.
1099#
1100
1101MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1102export MODLIB
1103
1104PHONY += prepare0
1105
1106export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
1107export MODORDER := $(extmod_prefix)modules.order
1108export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
1109
1110ifeq ($(KBUILD_EXTMOD),)
1111
1112build-dir	:= .
1113clean-dirs	:= $(sort . Documentation \
1114		     $(patsubst %/,%,$(filter %/, $(core-) \
1115			$(drivers-) $(libs-))))
1116
1117export ARCH_CORE	:= $(core-y)
1118export ARCH_LIB		:= $(filter %/, $(libs-y))
1119export ARCH_DRIVERS	:= $(drivers-y) $(drivers-m)
1120# Externally visible symbols (used by link-vmlinux.sh)
1121
1122KBUILD_VMLINUX_OBJS := ./built-in.a
1123ifdef CONFIG_MODULES
1124KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1125KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1126else
1127KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1128endif
1129
1130export KBUILD_VMLINUX_LIBS
1131export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1132
1133ifdef CONFIG_TRIM_UNUSED_KSYMS
1134# For the kernel to actually contain only the needed exported symbols,
1135# we have to build modules as well to determine what those symbols are.
1136KBUILD_MODULES := 1
1137endif
1138
1139# '$(AR) mPi' needs 'T' to workaround the bug of llvm-ar <= 14
1140quiet_cmd_ar_vmlinux.a = AR      $@
1141      cmd_ar_vmlinux.a = \
1142	rm -f $@; \
1143	$(AR) cDPrST $@ $(KBUILD_VMLINUX_OBJS); \
1144	$(AR) mPiT $$($(AR) t $@ | sed -n 1p) $@ $$($(AR) t $@ | grep -F -f $(srctree)/scripts/head-object-list.txt)
1145
1146targets += vmlinux.a
1147vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt FORCE
1148	$(call if_changed,ar_vmlinux.a)
1149
1150PHONY += vmlinux_o
1151vmlinux_o: vmlinux.a $(KBUILD_VMLINUX_LIBS)
1152	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o
1153
1154vmlinux.o modules.builtin.modinfo modules.builtin: vmlinux_o
1155	@:
1156
1157PHONY += vmlinux
1158# LDFLAGS_vmlinux in the top Makefile defines linker flags for the top vmlinux,
1159# not for decompressors. LDFLAGS_vmlinux in arch/*/boot/compressed/Makefile is
1160# unrelated; the decompressors just happen to have the same base name,
1161# arch/*/boot/compressed/vmlinux.
1162# Export LDFLAGS_vmlinux only to scripts/Makefile.vmlinux.
1163#
1164# _LDFLAGS_vmlinux is a workaround for the 'private export' bug:
1165#   https://savannah.gnu.org/bugs/?61463
1166# For Make > 4.4, the following simple code will work:
1167#  vmlinux: private export LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1168vmlinux: private _LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1169vmlinux: export LDFLAGS_vmlinux = $(_LDFLAGS_vmlinux)
1170vmlinux: vmlinux.o $(KBUILD_LDS) modpost
1171	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux
1172
1173# The actual objects are generated when descending,
1174# make sure no implicit rule kicks in
1175$(sort $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)): . ;
1176
1177ifeq ($(origin KERNELRELEASE),file)
1178filechk_kernel.release = $(srctree)/scripts/setlocalversion $(srctree)
1179else
1180filechk_kernel.release = echo $(KERNELRELEASE)
1181endif
1182
1183# Store (new) KERNELRELEASE string in include/config/kernel.release
1184include/config/kernel.release: FORCE
1185	$(call filechk,kernel.release)
1186
1187# Additional helpers built in scripts/
1188# Carefully list dependencies so we do not try to build scripts twice
1189# in parallel
1190PHONY += scripts
1191scripts: scripts_basic scripts_dtc
1192	$(Q)$(MAKE) $(build)=$(@)
1193
1194# Things we need to do before we recursively start building the kernel
1195# or the modules are listed in "prepare".
1196# A multi level approach is used. prepareN is processed before prepareN-1.
1197# archprepare is used in arch Makefiles and when processed asm symlink,
1198# version.h and scripts_basic is processed / created.
1199
1200PHONY += prepare archprepare
1201
1202archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1203	asm-generic $(version_h) include/generated/utsrelease.h \
1204	include/generated/compile.h include/generated/autoconf.h remove-stale-files
1205
1206prepare0: archprepare
1207	$(Q)$(MAKE) $(build)=scripts/mod
1208	$(Q)$(MAKE) $(build)=. prepare
1209
1210# All the preparing..
1211prepare: prepare0
1212ifdef CONFIG_RUST
1213	+$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh
1214	$(Q)$(MAKE) $(build)=rust
1215endif
1216
1217PHONY += remove-stale-files
1218remove-stale-files:
1219	$(Q)$(srctree)/scripts/remove-stale-files
1220
1221# Support for using generic headers in asm-generic
1222asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1223
1224PHONY += asm-generic uapi-asm-generic
1225asm-generic: uapi-asm-generic
1226	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1227	generic=include/asm-generic
1228uapi-asm-generic:
1229	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1230	generic=include/uapi/asm-generic
1231
1232# Generate some files
1233# ---------------------------------------------------------------------------
1234
1235# KERNELRELEASE can change from a few different places, meaning version.h
1236# needs to be updated, so this check is forced on all builds
1237
1238uts_len := 64
1239define filechk_utsrelease.h
1240	if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1241	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1242	  exit 1;                                                         \
1243	fi;                                                               \
1244	echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1245endef
1246
1247define filechk_version.h
1248	if [ $(SUBLEVEL) -gt 255 ]; then                                 \
1249		echo \#define LINUX_VERSION_CODE $(shell                 \
1250		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1251	else                                                             \
1252		echo \#define LINUX_VERSION_CODE $(shell                 \
1253		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1254	fi;                                                              \
1255	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
1256	((c) > 255 ? 255 : (c)))';                                       \
1257	echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
1258	echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
1259	echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1260endef
1261
1262$(version_h): private PATCHLEVEL := $(or $(PATCHLEVEL), 0)
1263$(version_h): private SUBLEVEL := $(or $(SUBLEVEL), 0)
1264$(version_h): FORCE
1265	$(call filechk,version.h)
1266
1267include/generated/utsrelease.h: include/config/kernel.release FORCE
1268	$(call filechk,utsrelease.h)
1269
1270filechk_compile.h = $(srctree)/scripts/mkcompile_h \
1271	"$(UTS_MACHINE)" "$(CONFIG_CC_VERSION_TEXT)" "$(LD)"
1272
1273include/generated/compile.h: FORCE
1274	$(call filechk,compile.h)
1275
1276PHONY += headerdep
1277headerdep:
1278	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1279	$(srctree)/scripts/headerdep.pl -I$(srctree)/include
1280
1281# ---------------------------------------------------------------------------
1282# Kernel headers
1283
1284#Default location for installed headers
1285export INSTALL_HDR_PATH = $(objtree)/usr
1286
1287quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1288      cmd_headers_install = \
1289	mkdir -p $(INSTALL_HDR_PATH); \
1290	rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1291	usr/include $(INSTALL_HDR_PATH)
1292
1293PHONY += headers_install
1294headers_install: headers
1295	$(call cmd,headers_install)
1296
1297PHONY += archheaders archscripts
1298
1299hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1300
1301PHONY += headers
1302headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1303	$(if $(filter um, $(SRCARCH)), $(error Headers not exportable for UML))
1304	$(Q)$(MAKE) $(hdr-inst)=include/uapi
1305	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1306
1307ifdef CONFIG_HEADERS_INSTALL
1308prepare: headers
1309endif
1310
1311PHONY += scripts_unifdef
1312scripts_unifdef: scripts_basic
1313	$(Q)$(MAKE) $(build)=scripts scripts/unifdef
1314
1315# ---------------------------------------------------------------------------
1316# Install
1317
1318# Many distributions have the custom install script, /sbin/installkernel.
1319# If DKMS is installed, 'make install' will eventually recurse back
1320# to this Makefile to build and install external modules.
1321# Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
1322
1323quiet_cmd_install = INSTALL $(INSTALL_PATH)
1324      cmd_install = unset sub_make_done; $(srctree)/scripts/install.sh
1325
1326# ---------------------------------------------------------------------------
1327# vDSO install
1328
1329PHONY += vdso_install
1330vdso_install: export INSTALL_FILES = $(vdso-install-y)
1331vdso_install:
1332	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vdsoinst
1333
1334# ---------------------------------------------------------------------------
1335# Tools
1336
1337ifdef CONFIG_OBJTOOL
1338prepare: tools/objtool
1339endif
1340
1341ifdef CONFIG_BPF
1342ifdef CONFIG_DEBUG_INFO_BTF
1343prepare: tools/bpf/resolve_btfids
1344endif
1345endif
1346
1347PHONY += resolve_btfids_clean
1348
1349resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1350
1351# tools/bpf/resolve_btfids directory might not exist
1352# in output directory, skip its clean in that case
1353resolve_btfids_clean:
1354ifneq ($(wildcard $(resolve_btfids_O)),)
1355	$(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1356endif
1357
1358# Clear a bunch of variables before executing the submake
1359ifeq ($(quiet),silent_)
1360tools_silent=s
1361endif
1362
1363tools/: FORCE
1364	$(Q)mkdir -p $(objtree)/tools
1365	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1366
1367tools/%: FORCE
1368	$(Q)mkdir -p $(objtree)/tools
1369	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1370
1371# ---------------------------------------------------------------------------
1372# Kernel selftest
1373
1374PHONY += kselftest
1375kselftest: headers
1376	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1377
1378kselftest-%: headers FORCE
1379	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1380
1381PHONY += kselftest-merge
1382kselftest-merge:
1383	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1384	$(Q)find $(srctree)/tools/testing/selftests -name config -o -name config.$(UTS_MACHINE) | \
1385		xargs $(srctree)/scripts/kconfig/merge_config.sh -y -m $(objtree)/.config
1386	$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1387
1388# ---------------------------------------------------------------------------
1389# Devicetree files
1390
1391ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1392dtstree := arch/$(SRCARCH)/boot/dts
1393endif
1394
1395ifneq ($(dtstree),)
1396
1397%.dtb: dtbs_prepare
1398	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1399
1400%.dtbo: dtbs_prepare
1401	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1402
1403PHONY += dtbs dtbs_prepare dtbs_install dtbs_check
1404dtbs: dtbs_prepare
1405	$(Q)$(MAKE) $(build)=$(dtstree) need-dtbslist=1
1406
1407# include/config/kernel.release is actually needed when installing DTBs because
1408# INSTALL_DTBS_PATH contains $(KERNELRELEASE). However, we do not want to make
1409# dtbs_install depend on it as dtbs_install may run as root.
1410dtbs_prepare: include/config/kernel.release scripts_dtc
1411
1412ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1413export CHECK_DTBS=y
1414endif
1415
1416ifneq ($(CHECK_DTBS),)
1417dtbs_prepare: dt_binding_schemas
1418endif
1419
1420dtbs_check: dtbs
1421
1422dtbs_install:
1423	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.dtbinst obj=$(dtstree)
1424
1425ifdef CONFIG_OF_EARLY_FLATTREE
1426all: dtbs
1427endif
1428
1429endif
1430
1431PHONY += scripts_dtc
1432scripts_dtc: scripts_basic
1433	$(Q)$(MAKE) $(build)=scripts/dtc
1434
1435ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1436export CHECK_DTBS=y
1437endif
1438
1439PHONY += dt_binding_check dt_binding_schemas
1440dt_binding_check: dt_binding_schemas scripts_dtc
1441	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1442
1443dt_binding_schemas:
1444	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1445
1446PHONY += dt_compatible_check
1447dt_compatible_check: dt_binding_schemas
1448	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1449
1450# ---------------------------------------------------------------------------
1451# Modules
1452
1453ifdef CONFIG_MODULES
1454
1455# By default, build modules as well
1456
1457all: modules
1458
1459# When we're building modules with modversions, we need to consider
1460# the built-in objects during the descend as well, in order to
1461# make sure the checksums are up to date before we record them.
1462ifdef CONFIG_MODVERSIONS
1463  KBUILD_BUILTIN := 1
1464endif
1465
1466# Build modules
1467#
1468
1469# *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFO_BTF_MODULES
1470# is an exception.
1471ifdef CONFIG_DEBUG_INFO_BTF_MODULES
1472KBUILD_BUILTIN := 1
1473modules: vmlinux
1474endif
1475
1476modules: modules_prepare
1477
1478# Target to prepare building external modules
1479modules_prepare: prepare
1480	$(Q)$(MAKE) $(build)=scripts scripts/module.lds
1481
1482endif # CONFIG_MODULES
1483
1484###
1485# Cleaning is done on three levels.
1486# make clean     Delete most generated files
1487#                Leave enough to build external modules
1488# make mrproper  Delete the current configuration, and all generated files
1489# make distclean Remove editor backup files, patch leftover files and the like
1490
1491# Directories & files removed with 'make clean'
1492CLEAN_FILES += vmlinux.symvers modules-only.symvers \
1493	       modules.builtin modules.builtin.modinfo modules.nsdeps \
1494	       compile_commands.json rust/test \
1495	       rust-project.json .vmlinux.objs .vmlinux.export.c
1496
1497# Directories & files removed with 'make mrproper'
1498MRPROPER_FILES += include/config include/generated          \
1499		  arch/$(SRCARCH)/include/generated .objdiff \
1500		  debian snap tar-install \
1501		  .config .config.old .version \
1502		  Module.symvers \
1503		  certs/signing_key.pem \
1504		  certs/x509.genkey \
1505		  vmlinux-gdb.py \
1506		  rpmbuild \
1507		  rust/libmacros.so
1508
1509# clean - Delete most, but leave enough to build external modules
1510#
1511clean: private rm-files := $(CLEAN_FILES)
1512
1513PHONY += archclean vmlinuxclean
1514
1515vmlinuxclean:
1516	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1517	$(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1518
1519clean: archclean vmlinuxclean resolve_btfids_clean
1520
1521# mrproper - Delete all generated files, including .config
1522#
1523mrproper: private rm-files := $(MRPROPER_FILES)
1524mrproper-dirs      := $(addprefix _mrproper_,scripts)
1525
1526PHONY += $(mrproper-dirs) mrproper
1527$(mrproper-dirs):
1528	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1529
1530mrproper: clean $(mrproper-dirs)
1531	$(call cmd,rmfiles)
1532	@find . $(RCS_FIND_IGNORE) \
1533		\( -name '*.rmeta' \) \
1534		-type f -print | xargs rm -f
1535
1536# distclean
1537#
1538PHONY += distclean
1539
1540distclean: mrproper
1541	@find . $(RCS_FIND_IGNORE) \
1542		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1543		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
1544		-o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1545		-o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1546		-type f -print | xargs rm -f
1547
1548
1549# Packaging of the kernel to various formats
1550# ---------------------------------------------------------------------------
1551
1552%src-pkg: FORCE
1553	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1554%pkg: include/config/kernel.release FORCE
1555	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1556
1557# Brief documentation of the typical targets used
1558# ---------------------------------------------------------------------------
1559
1560boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1561boards := $(sort $(notdir $(boards)))
1562board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1563board-dirs := $(sort $(notdir $(board-dirs:/=)))
1564
1565PHONY += help
1566help:
1567	@echo  'Cleaning targets:'
1568	@echo  '  clean		  - Remove most generated files but keep the config and'
1569	@echo  '                    enough build support to build external modules'
1570	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
1571	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
1572	@echo  ''
1573	@$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1574	@echo  ''
1575	@echo  'Other generic targets:'
1576	@echo  '  all		  - Build all targets marked with [*]'
1577	@echo  '* vmlinux	  - Build the bare kernel'
1578	@echo  '* modules	  - Build all modules'
1579	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1580	@echo  '  vdso_install    - Install unstripped vdso to INSTALL_MOD_PATH (default: /)'
1581	@echo  '  dir/            - Build all files in dir and below'
1582	@echo  '  dir/file.[ois]  - Build specified target only'
1583	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1584	@echo  '                    (requires compiler support for LLVM assembly generation)'
1585	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1586	@echo  '                    (requires a recent binutils and recent build (System.map))'
1587	@echo  '  dir/file.ko     - Build module including final link'
1588	@echo  '  modules_prepare - Set up for building external modules'
1589	@echo  '  tags/TAGS	  - Generate tags file for editors'
1590	@echo  '  cscope	  - Generate cscope index'
1591	@echo  '  gtags           - Generate GNU GLOBAL index'
1592	@echo  '  kernelrelease	  - Output the release version string (use with make -s)'
1593	@echo  '  kernelversion	  - Output the version stored in Makefile (use with make -s)'
1594	@echo  '  image_name	  - Output the image name (use with make -s)'
1595	@echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1596	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1597	 echo  ''
1598	@echo  'Static analysers:'
1599	@echo  '  checkstack      - Generate a list of stack hogs and consider all functions'
1600	@echo  '                    with a stack size larger than MINSTACKSIZE (default: 100)'
1601	@echo  '  versioncheck    - Sanity check on version.h usage'
1602	@echo  '  includecheck    - Check for duplicate included header files'
1603	@echo  '  export_report   - List the usages of all exported symbols'
1604	@echo  '  headerdep       - Detect inclusion cycles in headers'
1605	@echo  '  coccicheck      - Check with Coccinelle'
1606	@echo  '  clang-analyzer  - Check with clang static analyzer'
1607	@echo  '  clang-tidy      - Check with clang-tidy'
1608	@echo  ''
1609	@echo  'Tools:'
1610	@echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1611	@echo  ''
1612	@echo  'Kernel selftest:'
1613	@echo  '  kselftest         - Build and run kernel selftest'
1614	@echo  '                      Build, install, and boot kernel before'
1615	@echo  '                      running kselftest on it'
1616	@echo  '                      Run as root for full coverage'
1617	@echo  '  kselftest-all     - Build kernel selftest'
1618	@echo  '  kselftest-install - Build and install kernel selftest'
1619	@echo  '  kselftest-clean   - Remove all generated kselftest files'
1620	@echo  '  kselftest-merge   - Merge all the config dependencies of'
1621	@echo  '		      kselftest to existing .config.'
1622	@echo  ''
1623	@echo  'Rust targets:'
1624	@echo  '  rustavailable   - Checks whether the Rust toolchain is'
1625	@echo  '		    available and, if not, explains why.'
1626	@echo  '  rustfmt	  - Reformat all the Rust code in the kernel'
1627	@echo  '  rustfmtcheck	  - Checks if all the Rust code in the kernel'
1628	@echo  '		    is formatted, printing a diff otherwise.'
1629	@echo  '  rustdoc	  - Generate Rust documentation'
1630	@echo  '		    (requires kernel .config)'
1631	@echo  '  rusttest        - Runs the Rust tests'
1632	@echo  '                    (requires kernel .config; downloads external repos)'
1633	@echo  '  rust-analyzer	  - Generate rust-project.json rust-analyzer support file'
1634	@echo  '		    (requires kernel .config)'
1635	@echo  '  dir/file.[os]   - Build specified target only'
1636	@echo  '  dir/file.rsi    - Build macro expanded source, similar to C preprocessing.'
1637	@echo  '                    Run with RUSTFMT=n to skip reformatting if needed.'
1638	@echo  '                    The output is not intended to be compilable.'
1639	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1640	@echo  ''
1641	@$(if $(dtstree), \
1642		echo 'Devicetree:'; \
1643		echo '* dtbs               - Build device tree blobs for enabled boards'; \
1644		echo '  dtbs_install       - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1645		echo '  dt_binding_check   - Validate device tree binding documents and examples'; \
1646		echo '  dt_binding_schema  - Build processed device tree binding schemas'; \
1647		echo '  dtbs_check         - Validate device tree source files';\
1648		echo '')
1649
1650	@echo 'Userspace tools targets:'
1651	@echo '  use "make tools/help"'
1652	@echo '  or  "cd tools; make help"'
1653	@echo  ''
1654	@echo  'Kernel packaging:'
1655	@$(MAKE) -f $(srctree)/scripts/Makefile.package help
1656	@echo  ''
1657	@echo  'Documentation targets:'
1658	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1659	@echo  ''
1660	@echo  'Architecture-specific targets ($(SRCARCH)):'
1661	@$(or $(archhelp),\
1662		echo '  No architecture-specific help defined for $(SRCARCH)')
1663	@echo  ''
1664	@$(if $(boards), \
1665		$(foreach b, $(boards), \
1666		printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1667		echo '')
1668	@$(if $(board-dirs), \
1669		$(foreach b, $(board-dirs), \
1670		printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1671		printf "  %-16s - Show all of the above\\n" help-boards; \
1672		echo '')
1673
1674	@echo  '  make V=n   [targets] 1: verbose build'
1675	@echo  '                       2: give reason for rebuild of target'
1676	@echo  '                       V=1 and V=2 can be combined with V=12'
1677	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1678	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1679	@echo  '                       (sparse by default)'
1680	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1681	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1682	@echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3,c,e where'
1683	@echo  '		1: warnings which may be relevant and do not occur too often'
1684	@echo  '		2: warnings which occur quite often but may still be relevant'
1685	@echo  '		3: more obscure warnings, can most likely be ignored'
1686	@echo  '		c: extra checks in the configuration stage (Kconfig)'
1687	@echo  '		e: warnings are being treated as errors'
1688	@echo  '		Multiple levels can be combined with W=12 or W=123'
1689	@$(if $(dtstree), \
1690		echo '  make CHECK_DTBS=1 [targets] Check all generated dtb files against schema'; \
1691		echo '         This can be applied both to "dtbs" and to individual "foo.dtb" targets' ; \
1692		)
1693	@echo  ''
1694	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
1695	@echo  'For further info see the ./README file'
1696
1697
1698help-board-dirs := $(addprefix help-,$(board-dirs))
1699
1700help-boards: $(help-board-dirs)
1701
1702boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1703
1704$(help-board-dirs): help-%:
1705	@echo  'Architecture-specific targets ($(SRCARCH) $*):'
1706	@$(if $(boards-per-dir), \
1707		$(foreach b, $(boards-per-dir), \
1708		printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1709		echo '')
1710
1711
1712# Documentation targets
1713# ---------------------------------------------------------------------------
1714DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1715	       linkcheckdocs dochelp refcheckdocs texinfodocs infodocs
1716PHONY += $(DOC_TARGETS)
1717$(DOC_TARGETS):
1718	$(Q)$(MAKE) $(build)=Documentation $@
1719
1720
1721# Rust targets
1722# ---------------------------------------------------------------------------
1723
1724# "Is Rust available?" target
1725PHONY += rustavailable
1726rustavailable:
1727	+$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh && echo "Rust is available!"
1728
1729# Documentation target
1730#
1731# Using the singular to avoid running afoul of `no-dot-config-targets`.
1732PHONY += rustdoc
1733rustdoc: prepare
1734	$(Q)$(MAKE) $(build)=rust $@
1735
1736# Testing target
1737PHONY += rusttest
1738rusttest: prepare
1739	$(Q)$(MAKE) $(build)=rust $@
1740
1741# Formatting targets
1742PHONY += rustfmt rustfmtcheck
1743
1744# We skip `rust/alloc` since we want to minimize the diff w.r.t. upstream.
1745#
1746# We match using absolute paths since `find` does not resolve them
1747# when matching, which is a problem when e.g. `srctree` is `..`.
1748# We `grep` afterwards in order to remove the directory entry itself.
1749rustfmt:
1750	$(Q)find $(abs_srctree) -type f -name '*.rs' \
1751		-o -path $(abs_srctree)/rust/alloc -prune \
1752		-o -path $(abs_objtree)/rust/test -prune \
1753		| grep -Fv $(abs_srctree)/rust/alloc \
1754		| grep -Fv $(abs_objtree)/rust/test \
1755		| grep -Fv generated \
1756		| xargs $(RUSTFMT) $(rustfmt_flags)
1757
1758rustfmtcheck: rustfmt_flags = --check
1759rustfmtcheck: rustfmt
1760
1761# Misc
1762# ---------------------------------------------------------------------------
1763
1764PHONY += misc-check
1765misc-check:
1766	$(Q)$(srctree)/scripts/misc-check
1767
1768all: misc-check
1769
1770PHONY += scripts_gdb
1771scripts_gdb: prepare0
1772	$(Q)$(MAKE) $(build)=scripts/gdb
1773	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1774
1775ifdef CONFIG_GDB_SCRIPTS
1776all: scripts_gdb
1777endif
1778
1779else # KBUILD_EXTMOD
1780
1781filechk_kernel.release = echo $(KERNELRELEASE)
1782
1783###
1784# External module support.
1785# When building external modules the kernel used as basis is considered
1786# read-only, and no consistency checks are made and the make
1787# system is not used on the basis kernel. If updates are required
1788# in the basis kernel ordinary make commands (without M=...) must be used.
1789
1790# We are always building only modules.
1791KBUILD_BUILTIN :=
1792KBUILD_MODULES := 1
1793
1794build-dir := $(KBUILD_EXTMOD)
1795
1796compile_commands.json: $(extmod_prefix)compile_commands.json
1797PHONY += compile_commands.json
1798
1799clean-dirs := $(KBUILD_EXTMOD)
1800clean: private rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1801	$(KBUILD_EXTMOD)/compile_commands.json
1802
1803PHONY += prepare
1804# now expand this into a simple variable to reduce the cost of shell evaluations
1805prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT)
1806prepare:
1807	@if [ "$(CC_VERSION_TEXT)" != "$(CONFIG_CC_VERSION_TEXT)" ]; then \
1808		echo >&2 "warning: the compiler differs from the one used to build the kernel"; \
1809		echo >&2 "  The kernel was built by: $(CONFIG_CC_VERSION_TEXT)"; \
1810		echo >&2 "  You are using:           $(CC_VERSION_TEXT)"; \
1811	fi
1812
1813PHONY += help
1814help:
1815	@echo  '  Building external modules.'
1816	@echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1817	@echo  ''
1818	@echo  '  modules         - default target, build the module(s)'
1819	@echo  '  modules_install - install the module'
1820	@echo  '  clean           - remove generated files in module directory only'
1821	@echo  '  rust-analyzer	  - generate rust-project.json rust-analyzer support file'
1822	@echo  ''
1823
1824ifndef CONFIG_MODULES
1825modules modules_install: __external_modules_error
1826__external_modules_error:
1827	@echo >&2 '***'
1828	@echo >&2 '*** The present kernel disabled CONFIG_MODULES.'
1829	@echo >&2 '*** You cannot build or install external modules.'
1830	@echo >&2 '***'
1831	@false
1832endif
1833
1834endif # KBUILD_EXTMOD
1835
1836# ---------------------------------------------------------------------------
1837# Modules
1838
1839PHONY += modules modules_install modules_sign modules_prepare
1840
1841modules_install:
1842	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst \
1843	sign-only=$(if $(filter modules_install,$(MAKECMDGOALS)),,y)
1844
1845ifeq ($(CONFIG_MODULE_SIG),y)
1846# modules_sign is a subset of modules_install.
1847# 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1848modules_sign: modules_install
1849	@:
1850else
1851modules_sign:
1852	@echo >&2 '***'
1853	@echo >&2 '*** CONFIG_MODULE_SIG is disabled. You cannot sign modules.'
1854	@echo >&2 '***'
1855	@false
1856endif
1857
1858ifdef CONFIG_MODULES
1859
1860$(MODORDER): $(build-dir)
1861	@:
1862
1863# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
1864# This is solely useful to speed up test compiles.
1865modules: modpost
1866ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1867	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1868endif
1869
1870PHONY += modules_check
1871modules_check: $(MODORDER)
1872	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1873
1874else # CONFIG_MODULES
1875
1876modules:
1877	@:
1878
1879KBUILD_MODULES :=
1880
1881endif # CONFIG_MODULES
1882
1883PHONY += modpost
1884modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \
1885	 $(if $(KBUILD_MODULES), modules_check)
1886	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1887
1888# Single targets
1889# ---------------------------------------------------------------------------
1890# To build individual files in subdirectories, you can do like this:
1891#
1892#   make foo/bar/baz.s
1893#
1894# The supported suffixes for single-target are listed in 'single-targets'
1895#
1896# To build only under specific subdirectories, you can do like this:
1897#
1898#   make foo/bar/baz/
1899
1900ifdef single-build
1901
1902# .ko is special because modpost is needed
1903single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1904single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \
1905		$(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko)))
1906
1907$(single-ko): single_modules
1908	@:
1909$(single-no-ko): $(build-dir)
1910	@:
1911
1912# Remove MODORDER when done because it is not the real one.
1913PHONY += single_modules
1914single_modules: $(single-no-ko) modules_prepare
1915	$(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$(m:%.ko=%.o);) } > $(MODORDER)
1916	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1917ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1918	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1919endif
1920	$(Q)rm -f $(MODORDER)
1921
1922single-goals := $(addprefix $(build-dir)/, $(single-no-ko))
1923
1924KBUILD_MODULES := 1
1925
1926endif
1927
1928# Preset locale variables to speed up the build process. Limit locale
1929# tweaks to this spot to avoid wrong language settings when running
1930# make menuconfig etc.
1931# Error messages still appears in the original language
1932PHONY += $(build-dir)
1933$(build-dir): prepare
1934	$(Q)$(MAKE) $(build)=$@ need-builtin=1 need-modorder=1 $(single-goals)
1935
1936clean-dirs := $(addprefix _clean_, $(clean-dirs))
1937PHONY += $(clean-dirs) clean
1938$(clean-dirs):
1939	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1940
1941clean: $(clean-dirs)
1942	$(call cmd,rmfiles)
1943	@find $(or $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1944		\( -name '*.[aios]' -o -name '*.rsi' -o -name '*.ko' -o -name '.*.cmd' \
1945		-o -name '*.ko.*' \
1946		-o -name '*.dtb' -o -name '*.dtbo' \
1947		-o -name '*.dtb.S' -o -name '*.dtbo.S' \
1948		-o -name '*.dt.yaml' -o -name 'dtbs-list' \
1949		-o -name '*.dwo' -o -name '*.lst' \
1950		-o -name '*.su' -o -name '*.mod' \
1951		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1952		-o -name '*.lex.c' -o -name '*.tab.[ch]' \
1953		-o -name '*.asn1.[ch]' \
1954		-o -name '*.symtypes' -o -name 'modules.order' \
1955		-o -name '*.c.[012]*.*' \
1956		-o -name '*.ll' \
1957		-o -name '*.gcno' \
1958		-o -name '*.*.symversions' \) -type f -print \
1959		-o -name '.tmp_*' -print \
1960		| xargs rm -rf
1961
1962# Generate tags for editors
1963# ---------------------------------------------------------------------------
1964quiet_cmd_tags = GEN     $@
1965      cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1966
1967tags TAGS cscope gtags: FORCE
1968	$(call cmd,tags)
1969
1970# IDE support targets
1971PHONY += rust-analyzer
1972rust-analyzer:
1973	$(Q)$(MAKE) $(build)=rust $@
1974
1975# Script to generate missing namespace dependencies
1976# ---------------------------------------------------------------------------
1977
1978PHONY += nsdeps
1979nsdeps: export KBUILD_NSDEPS=1
1980nsdeps: modules
1981	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1982
1983# Clang Tooling
1984# ---------------------------------------------------------------------------
1985
1986quiet_cmd_gen_compile_commands = GEN     $@
1987      cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
1988
1989$(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
1990	$(if $(KBUILD_EXTMOD),, vmlinux.a $(KBUILD_VMLINUX_LIBS)) \
1991	$(if $(CONFIG_MODULES), $(MODORDER)) FORCE
1992	$(call if_changed,gen_compile_commands)
1993
1994targets += $(extmod_prefix)compile_commands.json
1995
1996PHONY += clang-tidy clang-analyzer
1997
1998ifdef CONFIG_CC_IS_CLANG
1999quiet_cmd_clang_tools = CHECK   $<
2000      cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
2001
2002clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
2003	$(call cmd,clang_tools)
2004else
2005clang-tidy clang-analyzer:
2006	@echo "$@ requires CC=clang" >&2
2007	@false
2008endif
2009
2010# Scripts to check various things for consistency
2011# ---------------------------------------------------------------------------
2012
2013PHONY += includecheck versioncheck coccicheck export_report
2014
2015includecheck:
2016	find $(srctree)/* $(RCS_FIND_IGNORE) \
2017		-name '*.[hcS]' -type f -print | sort \
2018		| xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
2019
2020versioncheck:
2021	find $(srctree)/* $(RCS_FIND_IGNORE) \
2022		-name '*.[hcS]' -type f -print | sort \
2023		| xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
2024
2025coccicheck:
2026	$(Q)$(BASH) $(srctree)/scripts/$@
2027
2028export_report:
2029	$(PERL) $(srctree)/scripts/export_report.pl
2030
2031PHONY += checkstack kernelrelease kernelversion image_name
2032
2033# UML needs a little special treatment here.  It wants to use the host
2034# toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
2035# else wants $(ARCH), including people doing cross-builds, which means
2036# that $(SUBARCH) doesn't work here.
2037ifeq ($(ARCH), um)
2038CHECKSTACK_ARCH := $(SUBARCH)
2039else
2040CHECKSTACK_ARCH := $(ARCH)
2041endif
2042MINSTACKSIZE	?= 100
2043checkstack:
2044	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
2045	$(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH) $(MINSTACKSIZE)
2046
2047kernelrelease:
2048	@$(filechk_kernel.release)
2049
2050kernelversion:
2051	@echo $(KERNELVERSION)
2052
2053image_name:
2054	@echo $(KBUILD_IMAGE)
2055
2056PHONY += run-command
2057run-command:
2058	$(Q)$(KBUILD_RUN_COMMAND)
2059
2060quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
2061      cmd_rmfiles = rm -rf $(rm-files)
2062
2063# read saved command lines for existing targets
2064existing-targets := $(wildcard $(sort $(targets)))
2065
2066-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
2067
2068endif # config-build
2069endif # mixed-build
2070endif # need-sub-make
2071
2072PHONY += FORCE
2073FORCE:
2074
2075# Declare the contents of the PHONY variable as phony.  We keep that
2076# information in a variable so we can use it in if_changed and friends.
2077.PHONY: $(PHONY)
2078