xref: /linux/Makefile (revision e516211f615fb54ce3429870eefc17469ae289b8)
1# SPDX-License-Identifier: GPL-2.0
2VERSION = 6
3PATCHLEVEL = 10
4SUBLEVEL = 0
5EXTRAVERSION = -rc7
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
510PAHOLE		= pahole
511RESOLVE_BTFIDS	= $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
512LEX		= flex
513YACC		= bison
514AWK		= awk
515INSTALLKERNEL  := installkernel
516PERL		= perl
517PYTHON3		= python3
518CHECK		= sparse
519BASH		= bash
520KGZIP		= gzip
521KBZIP2		= bzip2
522KLZOP		= lzop
523LZMA		= lzma
524LZ4		= lz4c
525XZ		= xz
526ZSTD		= zstd
527
528CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
529		  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
530NOSTDINC_FLAGS :=
531CFLAGS_MODULE   =
532RUSTFLAGS_MODULE =
533AFLAGS_MODULE   =
534LDFLAGS_MODULE  =
535CFLAGS_KERNEL	=
536RUSTFLAGS_KERNEL =
537AFLAGS_KERNEL	=
538LDFLAGS_vmlinux =
539
540# Use USERINCLUDE when you must reference the UAPI directories only.
541USERINCLUDE    := \
542		-I$(srctree)/arch/$(SRCARCH)/include/uapi \
543		-I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
544		-I$(srctree)/include/uapi \
545		-I$(objtree)/include/generated/uapi \
546                -include $(srctree)/include/linux/compiler-version.h \
547                -include $(srctree)/include/linux/kconfig.h
548
549# Use LINUXINCLUDE when you must reference the include/ directory.
550# Needed to be compatible with the O= option
551LINUXINCLUDE    := \
552		-I$(srctree)/arch/$(SRCARCH)/include \
553		-I$(objtree)/arch/$(SRCARCH)/include/generated \
554		$(if $(building_out_of_srctree),-I$(srctree)/include) \
555		-I$(objtree)/include \
556		$(USERINCLUDE)
557
558KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
559
560KBUILD_CFLAGS :=
561KBUILD_CFLAGS += -std=gnu11
562KBUILD_CFLAGS += -fshort-wchar
563KBUILD_CFLAGS += -funsigned-char
564KBUILD_CFLAGS += -fno-common
565KBUILD_CFLAGS += -fno-PIE
566KBUILD_CFLAGS += -fno-strict-aliasing
567
568KBUILD_CPPFLAGS := -D__KERNEL__
569KBUILD_RUSTFLAGS := $(rust_common_flags) \
570		    -Cpanic=abort -Cembed-bitcode=n -Clto=n \
571		    -Cforce-unwind-tables=n -Ccodegen-units=1 \
572		    -Csymbol-mangling-version=v0 \
573		    -Crelocation-model=static \
574		    -Zfunction-sections=n \
575		    -Dclippy::float_arithmetic
576
577KBUILD_AFLAGS_KERNEL :=
578KBUILD_CFLAGS_KERNEL :=
579KBUILD_RUSTFLAGS_KERNEL :=
580KBUILD_AFLAGS_MODULE  := -DMODULE
581KBUILD_CFLAGS_MODULE  := -DMODULE
582KBUILD_RUSTFLAGS_MODULE := --cfg MODULE
583KBUILD_LDFLAGS_MODULE :=
584KBUILD_LDFLAGS :=
585CLANG_FLAGS :=
586
587ifeq ($(KBUILD_CLIPPY),1)
588	RUSTC_OR_CLIPPY_QUIET := CLIPPY
589	RUSTC_OR_CLIPPY = $(CLIPPY_DRIVER)
590else
591	RUSTC_OR_CLIPPY_QUIET := RUSTC
592	RUSTC_OR_CLIPPY = $(RUSTC)
593endif
594
595ifdef RUST_LIB_SRC
596	export RUST_LIB_SRC
597endif
598
599# Allows the usage of unstable features in stable compilers.
600export RUSTC_BOOTSTRAP := 1
601
602export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG
603export RUSTC RUSTDOC RUSTFMT RUSTC_OR_CLIPPY_QUIET RUSTC_OR_CLIPPY BINDGEN
604export HOSTRUSTC KBUILD_HOSTRUSTFLAGS
605export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
606export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
607export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
608export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
609export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS
610
611export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
612export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
613export KBUILD_RUSTFLAGS RUSTFLAGS_KERNEL RUSTFLAGS_MODULE
614export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
615export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_RUSTFLAGS_MODULE KBUILD_LDFLAGS_MODULE
616export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL KBUILD_RUSTFLAGS_KERNEL
617
618# Files to ignore in find ... statements
619
620export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
621			  -name CVS -o -name .pc -o -name .hg -o -name .git \) \
622			  -prune -o
623
624# ===========================================================================
625# Rules shared between *config targets and build targets
626
627# Basic helpers built in scripts/basic/
628PHONY += scripts_basic
629scripts_basic:
630	$(Q)$(MAKE) $(build)=scripts/basic
631
632PHONY += outputmakefile
633ifdef building_out_of_srctree
634# Before starting out-of-tree build, make sure the source tree is clean.
635# outputmakefile generates a Makefile in the output directory, if using a
636# separate output directory. This allows convenient use of make in the
637# output directory.
638# At the same time when output Makefile generated, generate .gitignore to
639# ignore whole output directory
640
641quiet_cmd_makefile = GEN     Makefile
642      cmd_makefile = { \
643	echo "\# Automatically generated by $(srctree)/Makefile: don't edit"; \
644	echo "include $(srctree)/Makefile"; \
645	} > Makefile
646
647outputmakefile:
648	@if [ -f $(srctree)/.config -o \
649		 -d $(srctree)/include/config -o \
650		 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
651		echo >&2 "***"; \
652		echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
653		echo >&2 "*** in $(abs_srctree)";\
654		echo >&2 "***"; \
655		false; \
656	fi
657	$(Q)ln -fsn $(srctree) source
658	$(call cmd,makefile)
659	$(Q)test -e .gitignore || \
660	{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
661endif
662
663# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
664# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
665# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
666# and from include/config/auto.conf.cmd to detect the compiler upgrade.
667CC_VERSION_TEXT = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1))
668
669ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
670include $(srctree)/scripts/Makefile.clang
671endif
672
673# Include this also for config targets because some architectures need
674# cc-cross-prefix to determine CROSS_COMPILE.
675ifdef need-compiler
676include $(srctree)/scripts/Makefile.compiler
677endif
678
679ifdef config-build
680# ===========================================================================
681# *config targets only - make sure prerequisites are updated, and descend
682# in scripts/kconfig to make the *config target
683
684# Read arch-specific Makefile to set KBUILD_DEFCONFIG as needed.
685# KBUILD_DEFCONFIG may point out an alternative default configuration
686# used for 'make defconfig'
687include $(srctree)/arch/$(SRCARCH)/Makefile
688export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
689
690config: outputmakefile scripts_basic FORCE
691	$(Q)$(MAKE) $(build)=scripts/kconfig $@
692
693%config: outputmakefile scripts_basic FORCE
694	$(Q)$(MAKE) $(build)=scripts/kconfig $@
695
696else #!config-build
697# ===========================================================================
698# Build targets only - this includes vmlinux, arch-specific targets, clean
699# targets and others. In general all targets except *config targets.
700
701# If building an external module we do not care about the all: rule
702# but instead __all depend on modules
703PHONY += all
704ifeq ($(KBUILD_EXTMOD),)
705__all: all
706else
707__all: modules
708endif
709
710targets :=
711
712# Decide whether to build built-in, modular, or both.
713# Normally, just do built-in.
714
715KBUILD_MODULES :=
716KBUILD_BUILTIN := 1
717
718# If we have only "make modules", don't compile built-in objects.
719ifeq ($(MAKECMDGOALS),modules)
720  KBUILD_BUILTIN :=
721endif
722
723# If we have "make <whatever> modules", compile modules
724# in addition to whatever we do anyway.
725# Just "make" or "make all" shall build modules as well
726
727ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
728  KBUILD_MODULES := 1
729endif
730
731ifeq ($(MAKECMDGOALS),)
732  KBUILD_MODULES := 1
733endif
734
735export KBUILD_MODULES KBUILD_BUILTIN
736
737ifdef need-config
738include include/config/auto.conf
739endif
740
741ifeq ($(KBUILD_EXTMOD),)
742# Objects we will link into vmlinux / subdirs we need to visit
743core-y		:=
744drivers-y	:=
745libs-y		:= lib/
746endif # KBUILD_EXTMOD
747
748# The all: target is the default when no target is given on the
749# command line.
750# This allow a user to issue only 'make' to build a kernel including modules
751# Defaults to vmlinux, but the arch makefile usually adds further targets
752all: vmlinux
753
754CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage
755ifdef CONFIG_CC_IS_GCC
756CFLAGS_GCOV	+= -fno-tree-loop-im
757endif
758export CFLAGS_GCOV
759
760# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
761ifdef CONFIG_FUNCTION_TRACER
762  CC_FLAGS_FTRACE := -pg
763endif
764
765include $(srctree)/arch/$(SRCARCH)/Makefile
766
767ifdef need-config
768ifdef may-sync-config
769# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
770# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
771# because some architectures define CROSS_COMPILE there.
772include include/config/auto.conf.cmd
773
774$(KCONFIG_CONFIG):
775	@echo >&2 '***'
776	@echo >&2 '*** Configuration file "$@" not found!'
777	@echo >&2 '***'
778	@echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
779	@echo >&2 '*** "make menuconfig" or "make xconfig").'
780	@echo >&2 '***'
781	@/bin/false
782
783# The actual configuration files used during the build are stored in
784# include/generated/ and include/config/. Update them if .config is newer than
785# include/config/auto.conf (which mirrors .config).
786#
787# This exploits the 'multi-target pattern rule' trick.
788# The syncconfig should be executed only once to make all the targets.
789# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
790#
791# Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
792# so you cannot notice that Kconfig is waiting for the user input.
793%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h %/generated/rustc_cfg: $(KCONFIG_CONFIG)
794	$(Q)$(kecho) "  SYNC    $@"
795	$(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
796else # !may-sync-config
797# External modules and some install targets need include/generated/autoconf.h
798# and include/config/auto.conf but do not care if they are up-to-date.
799# Use auto.conf to trigger the test
800PHONY += include/config/auto.conf
801
802include/config/auto.conf:
803	@test -e include/generated/autoconf.h -a -e $@ || (		\
804	echo >&2;							\
805	echo >&2 "  ERROR: Kernel configuration is invalid.";		\
806	echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
807	echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";	\
808	echo >&2 ;							\
809	/bin/false)
810
811endif # may-sync-config
812endif # need-config
813
814KBUILD_CFLAGS	+= -fno-delete-null-pointer-checks
815
816ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
817KBUILD_CFLAGS += -O2
818KBUILD_RUSTFLAGS += -Copt-level=2
819else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
820KBUILD_CFLAGS += -Os
821KBUILD_RUSTFLAGS += -Copt-level=s
822endif
823
824# Always set `debug-assertions` and `overflow-checks` because their default
825# depends on `opt-level` and `debug-assertions`, respectively.
826KBUILD_RUSTFLAGS += -Cdebug-assertions=$(if $(CONFIG_RUST_DEBUG_ASSERTIONS),y,n)
827KBUILD_RUSTFLAGS += -Coverflow-checks=$(if $(CONFIG_RUST_OVERFLOW_CHECKS),y,n)
828
829# Tell gcc to never replace conditional load with a non-conditional one
830ifdef CONFIG_CC_IS_GCC
831# gcc-10 renamed --param=allow-store-data-races=0 to
832# -fno-allow-store-data-races.
833KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
834KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
835endif
836
837ifdef CONFIG_READABLE_ASM
838# Disable optimizations that make assembler listings hard to read.
839# reorder blocks reorders the control in the function
840# ipa clone creates specialized cloned functions
841# partial inlining inlines only parts of functions
842KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
843endif
844
845stackp-flags-y                                    := -fno-stack-protector
846stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
847stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
848
849KBUILD_CFLAGS += $(stackp-flags-y)
850
851KBUILD_RUSTFLAGS-$(CONFIG_WERROR) += -Dwarnings
852KBUILD_RUSTFLAGS += $(KBUILD_RUSTFLAGS-y)
853
854ifdef CONFIG_FRAME_POINTER
855KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
856KBUILD_RUSTFLAGS += -Cforce-frame-pointers=y
857else
858# Some targets (ARM with Thumb2, for example), can't be built with frame
859# pointers.  For those, we don't have FUNCTION_TRACER automatically
860# select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
861# incompatible with -fomit-frame-pointer with current GCC, so we don't use
862# -fomit-frame-pointer with FUNCTION_TRACER.
863# In the Rust target specification, "frame-pointer" is set explicitly
864# to "may-omit".
865ifndef CONFIG_FUNCTION_TRACER
866KBUILD_CFLAGS	+= -fomit-frame-pointer
867endif
868endif
869
870# Initialize all stack variables with a 0xAA pattern.
871ifdef CONFIG_INIT_STACK_ALL_PATTERN
872KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
873endif
874
875# Initialize all stack variables with a zero value.
876ifdef CONFIG_INIT_STACK_ALL_ZERO
877KBUILD_CFLAGS	+= -ftrivial-auto-var-init=zero
878ifdef CONFIG_CC_HAS_AUTO_VAR_INIT_ZERO_ENABLER
879# https://github.com/llvm/llvm-project/issues/44842
880CC_AUTO_VAR_INIT_ZERO_ENABLER := -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
881export CC_AUTO_VAR_INIT_ZERO_ENABLER
882KBUILD_CFLAGS	+= $(CC_AUTO_VAR_INIT_ZERO_ENABLER)
883endif
884endif
885
886# While VLAs have been removed, GCC produces unreachable stack probes
887# for the randomize_kstack_offset feature. Disable it for all compilers.
888KBUILD_CFLAGS	+= $(call cc-option, -fno-stack-clash-protection)
889
890# Clear used registers at func exit (to reduce data lifetime and ROP gadgets).
891ifdef CONFIG_ZERO_CALL_USED_REGS
892KBUILD_CFLAGS	+= -fzero-call-used-regs=used-gpr
893endif
894
895ifdef CONFIG_FUNCTION_TRACER
896ifdef CONFIG_FTRACE_MCOUNT_USE_CC
897  CC_FLAGS_FTRACE	+= -mrecord-mcount
898  ifdef CONFIG_HAVE_NOP_MCOUNT
899    ifeq ($(call cc-option-yn, -mnop-mcount),y)
900      CC_FLAGS_FTRACE	+= -mnop-mcount
901      CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
902    endif
903  endif
904endif
905ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
906  ifdef CONFIG_HAVE_OBJTOOL_NOP_MCOUNT
907    CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
908  endif
909endif
910ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
911  ifdef CONFIG_HAVE_C_RECORDMCOUNT
912    BUILD_C_RECORDMCOUNT := y
913    export BUILD_C_RECORDMCOUNT
914  endif
915endif
916ifdef CONFIG_HAVE_FENTRY
917  # s390-linux-gnu-gcc did not support -mfentry until gcc-9.
918  ifeq ($(call cc-option-yn, -mfentry),y)
919    CC_FLAGS_FTRACE	+= -mfentry
920    CC_FLAGS_USING	+= -DCC_USING_FENTRY
921  endif
922endif
923export CC_FLAGS_FTRACE
924KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
925KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
926endif
927
928# We trigger additional mismatches with less inlining
929ifdef CONFIG_DEBUG_SECTION_MISMATCH
930KBUILD_CFLAGS += -fno-inline-functions-called-once
931endif
932
933# `rustc`'s `-Zfunction-sections` applies to data too (as of 1.59.0).
934ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
935KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
936KBUILD_RUSTFLAGS_KERNEL += -Zfunction-sections=y
937LDFLAGS_vmlinux += --gc-sections
938endif
939
940ifdef CONFIG_SHADOW_CALL_STACK
941ifndef CONFIG_DYNAMIC_SCS
942CC_FLAGS_SCS	:= -fsanitize=shadow-call-stack
943KBUILD_CFLAGS	+= $(CC_FLAGS_SCS)
944endif
945export CC_FLAGS_SCS
946endif
947
948ifdef CONFIG_LTO_CLANG
949ifdef CONFIG_LTO_CLANG_THIN
950CC_FLAGS_LTO	:= -flto=thin -fsplit-lto-unit
951else
952CC_FLAGS_LTO	:= -flto
953endif
954CC_FLAGS_LTO	+= -fvisibility=hidden
955
956# Limit inlining across translation units to reduce binary size
957KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
958endif
959
960ifdef CONFIG_LTO
961KBUILD_CFLAGS	+= -fno-lto $(CC_FLAGS_LTO)
962KBUILD_AFLAGS	+= -fno-lto
963export CC_FLAGS_LTO
964endif
965
966ifdef CONFIG_CFI_CLANG
967CC_FLAGS_CFI	:= -fsanitize=kcfi
968KBUILD_CFLAGS	+= $(CC_FLAGS_CFI)
969export CC_FLAGS_CFI
970endif
971
972# Architectures can define flags to add/remove for floating-point support
973CC_FLAGS_FPU	+= -D_LINUX_FPU_COMPILATION_UNIT
974export CC_FLAGS_FPU
975export CC_FLAGS_NO_FPU
976
977ifneq ($(CONFIG_FUNCTION_ALIGNMENT),0)
978# Set the minimal function alignment. Use the newer GCC option
979# -fmin-function-alignment if it is available, or fall back to -falign-funtions.
980# See also CONFIG_CC_HAS_SANE_FUNCTION_ALIGNMENT.
981ifdef CONFIG_CC_HAS_MIN_FUNCTION_ALIGNMENT
982KBUILD_CFLAGS += -fmin-function-alignment=$(CONFIG_FUNCTION_ALIGNMENT)
983else
984KBUILD_CFLAGS += -falign-functions=$(CONFIG_FUNCTION_ALIGNMENT)
985endif
986endif
987
988# arch Makefile may override CC so keep this after arch Makefile is included
989NOSTDINC_FLAGS += -nostdinc
990
991# To gain proper coverage for CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE,
992# the kernel uses only C99 flexible arrays for dynamically sized trailing
993# arrays. Enforce this for everything that may examine structure sizes and
994# perform bounds checking.
995KBUILD_CFLAGS += $(call cc-option, -fstrict-flex-arrays=3)
996
997#Currently, disable -Wstringop-overflow for GCC 11, globally.
998KBUILD_CFLAGS-$(CONFIG_CC_NO_STRINGOP_OVERFLOW) += $(call cc-option, -Wno-stringop-overflow)
999KBUILD_CFLAGS-$(CONFIG_CC_STRINGOP_OVERFLOW) += $(call cc-option, -Wstringop-overflow)
1000
1001# disable invalid "can't wrap" optimizations for signed / pointers
1002KBUILD_CFLAGS	+= -fno-strict-overflow
1003
1004# Make sure -fstack-check isn't enabled (like gentoo apparently did)
1005KBUILD_CFLAGS  += -fno-stack-check
1006
1007# conserve stack if available
1008ifdef CONFIG_CC_IS_GCC
1009KBUILD_CFLAGS   += -fconserve-stack
1010endif
1011
1012# change __FILE__ to the relative path from the srctree
1013KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
1014
1015# include additional Makefiles when needed
1016include-y			:= scripts/Makefile.extrawarn
1017include-$(CONFIG_DEBUG_INFO)	+= scripts/Makefile.debug
1018include-$(CONFIG_DEBUG_INFO_BTF)+= scripts/Makefile.btf
1019include-$(CONFIG_KASAN)		+= scripts/Makefile.kasan
1020include-$(CONFIG_KCSAN)		+= scripts/Makefile.kcsan
1021include-$(CONFIG_KMSAN)		+= scripts/Makefile.kmsan
1022include-$(CONFIG_UBSAN)		+= scripts/Makefile.ubsan
1023include-$(CONFIG_KCOV)		+= scripts/Makefile.kcov
1024include-$(CONFIG_RANDSTRUCT)	+= scripts/Makefile.randstruct
1025include-$(CONFIG_GCC_PLUGINS)	+= scripts/Makefile.gcc-plugins
1026
1027include $(addprefix $(srctree)/, $(include-y))
1028
1029# scripts/Makefile.gcc-plugins is intentionally included last.
1030# Do not add $(call cc-option,...) below this line. When you build the kernel
1031# from the clean source tree, the GCC plugins do not exist at this point.
1032
1033# Add user supplied CPPFLAGS, AFLAGS, CFLAGS and RUSTFLAGS as the last assignments
1034KBUILD_CPPFLAGS += $(KCPPFLAGS)
1035KBUILD_AFLAGS   += $(KAFLAGS)
1036KBUILD_CFLAGS   += $(KCFLAGS)
1037KBUILD_RUSTFLAGS += $(KRUSTFLAGS)
1038
1039KBUILD_LDFLAGS_MODULE += --build-id=sha1
1040LDFLAGS_vmlinux += --build-id=sha1
1041
1042KBUILD_LDFLAGS	+= -z noexecstack
1043ifeq ($(CONFIG_LD_IS_BFD),y)
1044KBUILD_LDFLAGS	+= $(call ld-option,--no-warn-rwx-segments)
1045endif
1046
1047ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1048LDFLAGS_vmlinux	+= -X
1049endif
1050
1051ifeq ($(CONFIG_RELR),y)
1052# ld.lld before 15 did not support -z pack-relative-relocs.
1053LDFLAGS_vmlinux	+= $(call ld-option,--pack-dyn-relocs=relr,-z pack-relative-relocs)
1054endif
1055
1056# We never want expected sections to be placed heuristically by the
1057# linker. All sections should be explicitly named in the linker script.
1058ifdef CONFIG_LD_ORPHAN_WARN
1059LDFLAGS_vmlinux += --orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL)
1060endif
1061
1062# Align the bit size of userspace programs with the kernel
1063KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1064KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1065
1066# make the checker run with the right architecture
1067CHECKFLAGS += --arch=$(ARCH)
1068
1069# insure the checker run with the right endianness
1070CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1071
1072# the checker needs the correct machine size
1073CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1074
1075# Default kernel image to build when no specific target is given.
1076# KBUILD_IMAGE may be overruled on the command line or
1077# set in the environment
1078# Also any assignments in arch/$(ARCH)/Makefile take precedence over
1079# this default value
1080export KBUILD_IMAGE ?= vmlinux
1081
1082#
1083# INSTALL_PATH specifies where to place the updated kernel and system map
1084# images. Default is /boot, but you can set it to other values
1085export	INSTALL_PATH ?= /boot
1086
1087#
1088# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1089# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1090# an argument if needed. Otherwise it defaults to the kernel install path
1091#
1092export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1093
1094#
1095# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1096# relocations required by build roots.  This is not defined in the
1097# makefile but the argument can be passed to make if needed.
1098#
1099
1100MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1101export MODLIB
1102
1103PHONY += prepare0
1104
1105export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
1106export MODORDER := $(extmod_prefix)modules.order
1107export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
1108
1109ifeq ($(KBUILD_EXTMOD),)
1110
1111build-dir	:= .
1112clean-dirs	:= $(sort . Documentation \
1113		     $(patsubst %/,%,$(filter %/, $(core-) \
1114			$(drivers-) $(libs-))))
1115
1116export ARCH_CORE	:= $(core-y)
1117export ARCH_LIB		:= $(filter %/, $(libs-y))
1118export ARCH_DRIVERS	:= $(drivers-y) $(drivers-m)
1119# Externally visible symbols (used by link-vmlinux.sh)
1120
1121KBUILD_VMLINUX_OBJS := ./built-in.a
1122ifdef CONFIG_MODULES
1123KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1124KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1125else
1126KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1127endif
1128
1129export KBUILD_VMLINUX_LIBS
1130export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1131
1132ifdef CONFIG_TRIM_UNUSED_KSYMS
1133# For the kernel to actually contain only the needed exported symbols,
1134# we have to build modules as well to determine what those symbols are.
1135KBUILD_MODULES := 1
1136endif
1137
1138# '$(AR) mPi' needs 'T' to workaround the bug of llvm-ar <= 14
1139quiet_cmd_ar_vmlinux.a = AR      $@
1140      cmd_ar_vmlinux.a = \
1141	rm -f $@; \
1142	$(AR) cDPrST $@ $(KBUILD_VMLINUX_OBJS); \
1143	$(AR) mPiT $$($(AR) t $@ | sed -n 1p) $@ $$($(AR) t $@ | grep -F -f $(srctree)/scripts/head-object-list.txt)
1144
1145targets += vmlinux.a
1146vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt FORCE
1147	$(call if_changed,ar_vmlinux.a)
1148
1149PHONY += vmlinux_o
1150vmlinux_o: vmlinux.a $(KBUILD_VMLINUX_LIBS)
1151	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o
1152
1153vmlinux.o modules.builtin.modinfo modules.builtin: vmlinux_o
1154	@:
1155
1156PHONY += vmlinux
1157# LDFLAGS_vmlinux in the top Makefile defines linker flags for the top vmlinux,
1158# not for decompressors. LDFLAGS_vmlinux in arch/*/boot/compressed/Makefile is
1159# unrelated; the decompressors just happen to have the same base name,
1160# arch/*/boot/compressed/vmlinux.
1161# Export LDFLAGS_vmlinux only to scripts/Makefile.vmlinux.
1162#
1163# _LDFLAGS_vmlinux is a workaround for the 'private export' bug:
1164#   https://savannah.gnu.org/bugs/?61463
1165# For Make > 4.4, the following simple code will work:
1166#  vmlinux: private export LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1167vmlinux: private _LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1168vmlinux: export LDFLAGS_vmlinux = $(_LDFLAGS_vmlinux)
1169vmlinux: vmlinux.o $(KBUILD_LDS) modpost
1170	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux
1171
1172# The actual objects are generated when descending,
1173# make sure no implicit rule kicks in
1174$(sort $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)): . ;
1175
1176ifeq ($(origin KERNELRELEASE),file)
1177filechk_kernel.release = $(srctree)/scripts/setlocalversion $(srctree)
1178else
1179filechk_kernel.release = echo $(KERNELRELEASE)
1180endif
1181
1182# Store (new) KERNELRELEASE string in include/config/kernel.release
1183include/config/kernel.release: FORCE
1184	$(call filechk,kernel.release)
1185
1186# Additional helpers built in scripts/
1187# Carefully list dependencies so we do not try to build scripts twice
1188# in parallel
1189PHONY += scripts
1190scripts: scripts_basic scripts_dtc
1191	$(Q)$(MAKE) $(build)=$(@)
1192
1193# Things we need to do before we recursively start building the kernel
1194# or the modules are listed in "prepare".
1195# A multi level approach is used. prepareN is processed before prepareN-1.
1196# archprepare is used in arch Makefiles and when processed asm symlink,
1197# version.h and scripts_basic is processed / created.
1198
1199PHONY += prepare archprepare
1200
1201archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1202	asm-generic $(version_h) include/generated/utsrelease.h \
1203	include/generated/compile.h include/generated/autoconf.h remove-stale-files
1204
1205prepare0: archprepare
1206	$(Q)$(MAKE) $(build)=scripts/mod
1207	$(Q)$(MAKE) $(build)=. prepare
1208
1209# All the preparing..
1210prepare: prepare0
1211ifdef CONFIG_RUST
1212	+$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh
1213	$(Q)$(MAKE) $(build)=rust
1214endif
1215
1216PHONY += remove-stale-files
1217remove-stale-files:
1218	$(Q)$(srctree)/scripts/remove-stale-files
1219
1220# Support for using generic headers in asm-generic
1221asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1222
1223PHONY += asm-generic uapi-asm-generic
1224asm-generic: uapi-asm-generic
1225	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1226	generic=include/asm-generic
1227uapi-asm-generic:
1228	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1229	generic=include/uapi/asm-generic
1230
1231# Generate some files
1232# ---------------------------------------------------------------------------
1233
1234# KERNELRELEASE can change from a few different places, meaning version.h
1235# needs to be updated, so this check is forced on all builds
1236
1237uts_len := 64
1238define filechk_utsrelease.h
1239	if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1240	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1241	  exit 1;                                                         \
1242	fi;                                                               \
1243	echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1244endef
1245
1246define filechk_version.h
1247	if [ $(SUBLEVEL) -gt 255 ]; then                                 \
1248		echo \#define LINUX_VERSION_CODE $(shell                 \
1249		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1250	else                                                             \
1251		echo \#define LINUX_VERSION_CODE $(shell                 \
1252		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1253	fi;                                                              \
1254	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
1255	((c) > 255 ? 255 : (c)))';                                       \
1256	echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
1257	echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
1258	echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1259endef
1260
1261$(version_h): private PATCHLEVEL := $(or $(PATCHLEVEL), 0)
1262$(version_h): private SUBLEVEL := $(or $(SUBLEVEL), 0)
1263$(version_h): FORCE
1264	$(call filechk,version.h)
1265
1266include/generated/utsrelease.h: include/config/kernel.release FORCE
1267	$(call filechk,utsrelease.h)
1268
1269filechk_compile.h = $(srctree)/scripts/mkcompile_h \
1270	"$(UTS_MACHINE)" "$(CONFIG_CC_VERSION_TEXT)" "$(LD)"
1271
1272include/generated/compile.h: FORCE
1273	$(call filechk,compile.h)
1274
1275PHONY += headerdep
1276headerdep:
1277	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1278	$(srctree)/scripts/headerdep.pl -I$(srctree)/include
1279
1280# ---------------------------------------------------------------------------
1281# Kernel headers
1282
1283#Default location for installed headers
1284export INSTALL_HDR_PATH = $(objtree)/usr
1285
1286quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1287      cmd_headers_install = \
1288	mkdir -p $(INSTALL_HDR_PATH); \
1289	rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1290	usr/include $(INSTALL_HDR_PATH)
1291
1292PHONY += headers_install
1293headers_install: headers
1294	$(call cmd,headers_install)
1295
1296PHONY += archheaders archscripts
1297
1298hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1299
1300PHONY += headers
1301headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1302	$(if $(filter um, $(SRCARCH)), $(error Headers not exportable for UML))
1303	$(Q)$(MAKE) $(hdr-inst)=include/uapi
1304	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1305
1306ifdef CONFIG_HEADERS_INSTALL
1307prepare: headers
1308endif
1309
1310PHONY += scripts_unifdef
1311scripts_unifdef: scripts_basic
1312	$(Q)$(MAKE) $(build)=scripts scripts/unifdef
1313
1314# ---------------------------------------------------------------------------
1315# Install
1316
1317# Many distributions have the custom install script, /sbin/installkernel.
1318# If DKMS is installed, 'make install' will eventually recurse back
1319# to this Makefile to build and install external modules.
1320# Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
1321
1322quiet_cmd_install = INSTALL $(INSTALL_PATH)
1323      cmd_install = unset sub_make_done; $(srctree)/scripts/install.sh
1324
1325# ---------------------------------------------------------------------------
1326# vDSO install
1327
1328PHONY += vdso_install
1329vdso_install: export INSTALL_FILES = $(vdso-install-y)
1330vdso_install:
1331	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vdsoinst
1332
1333# ---------------------------------------------------------------------------
1334# Tools
1335
1336ifdef CONFIG_OBJTOOL
1337prepare: tools/objtool
1338endif
1339
1340ifdef CONFIG_BPF
1341ifdef CONFIG_DEBUG_INFO_BTF
1342prepare: tools/bpf/resolve_btfids
1343endif
1344endif
1345
1346PHONY += resolve_btfids_clean
1347
1348resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1349
1350# tools/bpf/resolve_btfids directory might not exist
1351# in output directory, skip its clean in that case
1352resolve_btfids_clean:
1353ifneq ($(wildcard $(resolve_btfids_O)),)
1354	$(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1355endif
1356
1357# Clear a bunch of variables before executing the submake
1358ifeq ($(quiet),silent_)
1359tools_silent=s
1360endif
1361
1362tools/: FORCE
1363	$(Q)mkdir -p $(objtree)/tools
1364	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1365
1366tools/%: FORCE
1367	$(Q)mkdir -p $(objtree)/tools
1368	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1369
1370# ---------------------------------------------------------------------------
1371# Kernel selftest
1372
1373PHONY += kselftest
1374kselftest: headers
1375	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1376
1377kselftest-%: headers FORCE
1378	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1379
1380PHONY += kselftest-merge
1381kselftest-merge:
1382	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1383	$(Q)find $(srctree)/tools/testing/selftests -name config -o -name config.$(UTS_MACHINE) | \
1384		xargs $(srctree)/scripts/kconfig/merge_config.sh -y -m $(objtree)/.config
1385	$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1386
1387# ---------------------------------------------------------------------------
1388# Devicetree files
1389
1390ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1391dtstree := arch/$(SRCARCH)/boot/dts
1392endif
1393
1394ifneq ($(dtstree),)
1395
1396%.dtb: dtbs_prepare
1397	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1398
1399%.dtbo: dtbs_prepare
1400	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1401
1402PHONY += dtbs dtbs_prepare dtbs_install dtbs_check
1403dtbs: dtbs_prepare
1404	$(Q)$(MAKE) $(build)=$(dtstree) need-dtbslist=1
1405
1406# include/config/kernel.release is actually needed when installing DTBs because
1407# INSTALL_DTBS_PATH contains $(KERNELRELEASE). However, we do not want to make
1408# dtbs_install depend on it as dtbs_install may run as root.
1409dtbs_prepare: include/config/kernel.release scripts_dtc
1410
1411ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1412export CHECK_DTBS=y
1413endif
1414
1415ifneq ($(CHECK_DTBS),)
1416dtbs_prepare: dt_binding_schemas
1417endif
1418
1419dtbs_check: dtbs
1420
1421dtbs_install:
1422	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.dtbinst obj=$(dtstree)
1423
1424ifdef CONFIG_OF_EARLY_FLATTREE
1425all: dtbs
1426endif
1427
1428endif
1429
1430PHONY += scripts_dtc
1431scripts_dtc: scripts_basic
1432	$(Q)$(MAKE) $(build)=scripts/dtc
1433
1434ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1435export CHECK_DTBS=y
1436endif
1437
1438PHONY += dt_binding_check dt_binding_schemas
1439dt_binding_check: dt_binding_schemas scripts_dtc
1440	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1441
1442dt_binding_schemas:
1443	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1444
1445PHONY += dt_compatible_check
1446dt_compatible_check: dt_binding_schemas
1447	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1448
1449# ---------------------------------------------------------------------------
1450# Modules
1451
1452ifdef CONFIG_MODULES
1453
1454# By default, build modules as well
1455
1456all: modules
1457
1458# When we're building modules with modversions, we need to consider
1459# the built-in objects during the descend as well, in order to
1460# make sure the checksums are up to date before we record them.
1461ifdef CONFIG_MODVERSIONS
1462  KBUILD_BUILTIN := 1
1463endif
1464
1465# Build modules
1466#
1467
1468# *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFO_BTF_MODULES
1469# is an exception.
1470ifdef CONFIG_DEBUG_INFO_BTF_MODULES
1471KBUILD_BUILTIN := 1
1472modules: vmlinux
1473endif
1474
1475modules: modules_prepare
1476
1477# Target to prepare building external modules
1478modules_prepare: prepare
1479	$(Q)$(MAKE) $(build)=scripts scripts/module.lds
1480
1481endif # CONFIG_MODULES
1482
1483###
1484# Cleaning is done on three levels.
1485# make clean     Delete most generated files
1486#                Leave enough to build external modules
1487# make mrproper  Delete the current configuration, and all generated files
1488# make distclean Remove editor backup files, patch leftover files and the like
1489
1490# Directories & files removed with 'make clean'
1491CLEAN_FILES += vmlinux.symvers modules-only.symvers \
1492	       modules.builtin modules.builtin.modinfo modules.nsdeps \
1493	       compile_commands.json rust/test \
1494	       rust-project.json .vmlinux.objs .vmlinux.export.c
1495
1496# Directories & files removed with 'make mrproper'
1497MRPROPER_FILES += include/config include/generated          \
1498		  arch/$(SRCARCH)/include/generated .objdiff \
1499		  debian snap tar-install \
1500		  .config .config.old .version \
1501		  Module.symvers \
1502		  certs/signing_key.pem \
1503		  certs/x509.genkey \
1504		  vmlinux-gdb.py \
1505		  rpmbuild \
1506		  rust/libmacros.so
1507
1508# clean - Delete most, but leave enough to build external modules
1509#
1510clean: private rm-files := $(CLEAN_FILES)
1511
1512PHONY += archclean vmlinuxclean
1513
1514vmlinuxclean:
1515	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1516	$(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1517
1518clean: archclean vmlinuxclean resolve_btfids_clean
1519
1520# mrproper - Delete all generated files, including .config
1521#
1522mrproper: private rm-files := $(MRPROPER_FILES)
1523mrproper-dirs      := $(addprefix _mrproper_,scripts)
1524
1525PHONY += $(mrproper-dirs) mrproper
1526$(mrproper-dirs):
1527	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1528
1529mrproper: clean $(mrproper-dirs)
1530	$(call cmd,rmfiles)
1531	@find . $(RCS_FIND_IGNORE) \
1532		\( -name '*.rmeta' \) \
1533		-type f -print | xargs rm -f
1534
1535# distclean
1536#
1537PHONY += distclean
1538
1539distclean: mrproper
1540	@find . $(RCS_FIND_IGNORE) \
1541		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1542		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
1543		-o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1544		-o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1545		-type f -print | xargs rm -f
1546
1547
1548# Packaging of the kernel to various formats
1549# ---------------------------------------------------------------------------
1550
1551%src-pkg: FORCE
1552	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1553%pkg: include/config/kernel.release FORCE
1554	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1555
1556# Brief documentation of the typical targets used
1557# ---------------------------------------------------------------------------
1558
1559boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1560boards := $(sort $(notdir $(boards)))
1561board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1562board-dirs := $(sort $(notdir $(board-dirs:/=)))
1563
1564PHONY += help
1565help:
1566	@echo  'Cleaning targets:'
1567	@echo  '  clean		  - Remove most generated files but keep the config and'
1568	@echo  '                    enough build support to build external modules'
1569	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
1570	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
1571	@echo  ''
1572	@$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1573	@echo  ''
1574	@echo  'Other generic targets:'
1575	@echo  '  all		  - Build all targets marked with [*]'
1576	@echo  '* vmlinux	  - Build the bare kernel'
1577	@echo  '* modules	  - Build all modules'
1578	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1579	@echo  '  vdso_install    - Install unstripped vdso to INSTALL_MOD_PATH (default: /)'
1580	@echo  '  dir/            - Build all files in dir and below'
1581	@echo  '  dir/file.[ois]  - Build specified target only'
1582	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1583	@echo  '                    (requires compiler support for LLVM assembly generation)'
1584	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1585	@echo  '                    (requires a recent binutils and recent build (System.map))'
1586	@echo  '  dir/file.ko     - Build module including final link'
1587	@echo  '  modules_prepare - Set up for building external modules'
1588	@echo  '  tags/TAGS	  - Generate tags file for editors'
1589	@echo  '  cscope	  - Generate cscope index'
1590	@echo  '  gtags           - Generate GNU GLOBAL index'
1591	@echo  '  kernelrelease	  - Output the release version string (use with make -s)'
1592	@echo  '  kernelversion	  - Output the version stored in Makefile (use with make -s)'
1593	@echo  '  image_name	  - Output the image name (use with make -s)'
1594	@echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1595	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1596	 echo  ''
1597	@echo  'Static analysers:'
1598	@echo  '  checkstack      - Generate a list of stack hogs and consider all functions'
1599	@echo  '                    with a stack size larger than MINSTACKSIZE (default: 100)'
1600	@echo  '  versioncheck    - Sanity check on version.h usage'
1601	@echo  '  includecheck    - Check for duplicate included header files'
1602	@echo  '  export_report   - List the usages of all exported symbols'
1603	@echo  '  headerdep       - Detect inclusion cycles in headers'
1604	@echo  '  coccicheck      - Check with Coccinelle'
1605	@echo  '  clang-analyzer  - Check with clang static analyzer'
1606	@echo  '  clang-tidy      - Check with clang-tidy'
1607	@echo  ''
1608	@echo  'Tools:'
1609	@echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1610	@echo  ''
1611	@echo  'Kernel selftest:'
1612	@echo  '  kselftest         - Build and run kernel selftest'
1613	@echo  '                      Build, install, and boot kernel before'
1614	@echo  '                      running kselftest on it'
1615	@echo  '                      Run as root for full coverage'
1616	@echo  '  kselftest-all     - Build kernel selftest'
1617	@echo  '  kselftest-install - Build and install kernel selftest'
1618	@echo  '  kselftest-clean   - Remove all generated kselftest files'
1619	@echo  '  kselftest-merge   - Merge all the config dependencies of'
1620	@echo  '		      kselftest to existing .config.'
1621	@echo  ''
1622	@echo  'Rust targets:'
1623	@echo  '  rustavailable   - Checks whether the Rust toolchain is'
1624	@echo  '		    available and, if not, explains why.'
1625	@echo  '  rustfmt	  - Reformat all the Rust code in the kernel'
1626	@echo  '  rustfmtcheck	  - Checks if all the Rust code in the kernel'
1627	@echo  '		    is formatted, printing a diff otherwise.'
1628	@echo  '  rustdoc	  - Generate Rust documentation'
1629	@echo  '		    (requires kernel .config)'
1630	@echo  '  rusttest        - Runs the Rust tests'
1631	@echo  '                    (requires kernel .config; downloads external repos)'
1632	@echo  '  rust-analyzer	  - Generate rust-project.json rust-analyzer support file'
1633	@echo  '		    (requires kernel .config)'
1634	@echo  '  dir/file.[os]   - Build specified target only'
1635	@echo  '  dir/file.rsi    - Build macro expanded source, similar to C preprocessing.'
1636	@echo  '                    Run with RUSTFMT=n to skip reformatting if needed.'
1637	@echo  '                    The output is not intended to be compilable.'
1638	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1639	@echo  ''
1640	@$(if $(dtstree), \
1641		echo 'Devicetree:'; \
1642		echo '* dtbs               - Build device tree blobs for enabled boards'; \
1643		echo '  dtbs_install       - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1644		echo '  dt_binding_check   - Validate device tree binding documents and examples'; \
1645		echo '  dt_binding_schema  - Build processed device tree binding schemas'; \
1646		echo '  dtbs_check         - Validate device tree source files';\
1647		echo '')
1648
1649	@echo 'Userspace tools targets:'
1650	@echo '  use "make tools/help"'
1651	@echo '  or  "cd tools; make help"'
1652	@echo  ''
1653	@echo  'Kernel packaging:'
1654	@$(MAKE) -f $(srctree)/scripts/Makefile.package help
1655	@echo  ''
1656	@echo  'Documentation targets:'
1657	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1658	@echo  ''
1659	@echo  'Architecture-specific targets ($(SRCARCH)):'
1660	@$(or $(archhelp),\
1661		echo '  No architecture-specific help defined for $(SRCARCH)')
1662	@echo  ''
1663	@$(if $(boards), \
1664		$(foreach b, $(boards), \
1665		printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1666		echo '')
1667	@$(if $(board-dirs), \
1668		$(foreach b, $(board-dirs), \
1669		printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1670		printf "  %-16s - Show all of the above\\n" help-boards; \
1671		echo '')
1672
1673	@echo  '  make V=n   [targets] 1: verbose build'
1674	@echo  '                       2: give reason for rebuild of target'
1675	@echo  '                       V=1 and V=2 can be combined with V=12'
1676	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1677	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1678	@echo  '                       (sparse by default)'
1679	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1680	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1681	@echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3,c,e where'
1682	@echo  '		1: warnings which may be relevant and do not occur too often'
1683	@echo  '		2: warnings which occur quite often but may still be relevant'
1684	@echo  '		3: more obscure warnings, can most likely be ignored'
1685	@echo  '		c: extra checks in the configuration stage (Kconfig)'
1686	@echo  '		e: warnings are being treated as errors'
1687	@echo  '		Multiple levels can be combined with W=12 or W=123'
1688	@$(if $(dtstree), \
1689		echo '  make CHECK_DTBS=1 [targets] Check all generated dtb files against schema'; \
1690		echo '         This can be applied both to "dtbs" and to individual "foo.dtb" targets' ; \
1691		)
1692	@echo  ''
1693	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
1694	@echo  'For further info see the ./README file'
1695
1696
1697help-board-dirs := $(addprefix help-,$(board-dirs))
1698
1699help-boards: $(help-board-dirs)
1700
1701boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1702
1703$(help-board-dirs): help-%:
1704	@echo  'Architecture-specific targets ($(SRCARCH) $*):'
1705	@$(if $(boards-per-dir), \
1706		$(foreach b, $(boards-per-dir), \
1707		printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1708		echo '')
1709
1710
1711# Documentation targets
1712# ---------------------------------------------------------------------------
1713DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1714	       linkcheckdocs dochelp refcheckdocs texinfodocs infodocs
1715PHONY += $(DOC_TARGETS)
1716$(DOC_TARGETS):
1717	$(Q)$(MAKE) $(build)=Documentation $@
1718
1719
1720# Rust targets
1721# ---------------------------------------------------------------------------
1722
1723# "Is Rust available?" target
1724PHONY += rustavailable
1725rustavailable:
1726	+$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh && echo "Rust is available!"
1727
1728# Documentation target
1729#
1730# Using the singular to avoid running afoul of `no-dot-config-targets`.
1731PHONY += rustdoc
1732rustdoc: prepare
1733	$(Q)$(MAKE) $(build)=rust $@
1734
1735# Testing target
1736PHONY += rusttest
1737rusttest: prepare
1738	$(Q)$(MAKE) $(build)=rust $@
1739
1740# Formatting targets
1741PHONY += rustfmt rustfmtcheck
1742
1743# We skip `rust/alloc` since we want to minimize the diff w.r.t. upstream.
1744#
1745# We match using absolute paths since `find` does not resolve them
1746# when matching, which is a problem when e.g. `srctree` is `..`.
1747# We `grep` afterwards in order to remove the directory entry itself.
1748rustfmt:
1749	$(Q)find $(abs_srctree) -type f -name '*.rs' \
1750		-o -path $(abs_srctree)/rust/alloc -prune \
1751		-o -path $(abs_objtree)/rust/test -prune \
1752		| grep -Fv $(abs_srctree)/rust/alloc \
1753		| grep -Fv $(abs_objtree)/rust/test \
1754		| grep -Fv generated \
1755		| xargs $(RUSTFMT) $(rustfmt_flags)
1756
1757rustfmtcheck: rustfmt_flags = --check
1758rustfmtcheck: rustfmt
1759
1760# Misc
1761# ---------------------------------------------------------------------------
1762
1763PHONY += misc-check
1764misc-check:
1765	$(Q)$(srctree)/scripts/misc-check
1766
1767all: misc-check
1768
1769PHONY += scripts_gdb
1770scripts_gdb: prepare0
1771	$(Q)$(MAKE) $(build)=scripts/gdb
1772	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1773
1774ifdef CONFIG_GDB_SCRIPTS
1775all: scripts_gdb
1776endif
1777
1778else # KBUILD_EXTMOD
1779
1780filechk_kernel.release = echo $(KERNELRELEASE)
1781
1782###
1783# External module support.
1784# When building external modules the kernel used as basis is considered
1785# read-only, and no consistency checks are made and the make
1786# system is not used on the basis kernel. If updates are required
1787# in the basis kernel ordinary make commands (without M=...) must be used.
1788
1789# We are always building only modules.
1790KBUILD_BUILTIN :=
1791KBUILD_MODULES := 1
1792
1793build-dir := $(KBUILD_EXTMOD)
1794
1795compile_commands.json: $(extmod_prefix)compile_commands.json
1796PHONY += compile_commands.json
1797
1798clean-dirs := $(KBUILD_EXTMOD)
1799clean: private rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1800	$(KBUILD_EXTMOD)/compile_commands.json
1801
1802PHONY += prepare
1803# now expand this into a simple variable to reduce the cost of shell evaluations
1804prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT)
1805prepare:
1806	@if [ "$(CC_VERSION_TEXT)" != "$(CONFIG_CC_VERSION_TEXT)" ]; then \
1807		echo >&2 "warning: the compiler differs from the one used to build the kernel"; \
1808		echo >&2 "  The kernel was built by: $(CONFIG_CC_VERSION_TEXT)"; \
1809		echo >&2 "  You are using:           $(CC_VERSION_TEXT)"; \
1810	fi
1811
1812PHONY += help
1813help:
1814	@echo  '  Building external modules.'
1815	@echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1816	@echo  ''
1817	@echo  '  modules         - default target, build the module(s)'
1818	@echo  '  modules_install - install the module'
1819	@echo  '  clean           - remove generated files in module directory only'
1820	@echo  '  rust-analyzer	  - generate rust-project.json rust-analyzer support file'
1821	@echo  ''
1822
1823ifndef CONFIG_MODULES
1824modules modules_install: __external_modules_error
1825__external_modules_error:
1826	@echo >&2 '***'
1827	@echo >&2 '*** The present kernel disabled CONFIG_MODULES.'
1828	@echo >&2 '*** You cannot build or install external modules.'
1829	@echo >&2 '***'
1830	@false
1831endif
1832
1833endif # KBUILD_EXTMOD
1834
1835# ---------------------------------------------------------------------------
1836# Modules
1837
1838PHONY += modules modules_install modules_sign modules_prepare
1839
1840modules_install:
1841	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst \
1842	sign-only=$(if $(filter modules_install,$(MAKECMDGOALS)),,y)
1843
1844ifeq ($(CONFIG_MODULE_SIG),y)
1845# modules_sign is a subset of modules_install.
1846# 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1847modules_sign: modules_install
1848	@:
1849else
1850modules_sign:
1851	@echo >&2 '***'
1852	@echo >&2 '*** CONFIG_MODULE_SIG is disabled. You cannot sign modules.'
1853	@echo >&2 '***'
1854	@false
1855endif
1856
1857ifdef CONFIG_MODULES
1858
1859$(MODORDER): $(build-dir)
1860	@:
1861
1862# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
1863# This is solely useful to speed up test compiles.
1864modules: modpost
1865ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1866	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1867endif
1868
1869PHONY += modules_check
1870modules_check: $(MODORDER)
1871	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1872
1873else # CONFIG_MODULES
1874
1875modules:
1876	@:
1877
1878KBUILD_MODULES :=
1879
1880endif # CONFIG_MODULES
1881
1882PHONY += modpost
1883modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \
1884	 $(if $(KBUILD_MODULES), modules_check)
1885	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1886
1887# Single targets
1888# ---------------------------------------------------------------------------
1889# To build individual files in subdirectories, you can do like this:
1890#
1891#   make foo/bar/baz.s
1892#
1893# The supported suffixes for single-target are listed in 'single-targets'
1894#
1895# To build only under specific subdirectories, you can do like this:
1896#
1897#   make foo/bar/baz/
1898
1899ifdef single-build
1900
1901# .ko is special because modpost is needed
1902single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1903single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \
1904		$(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko)))
1905
1906$(single-ko): single_modules
1907	@:
1908$(single-no-ko): $(build-dir)
1909	@:
1910
1911# Remove MODORDER when done because it is not the real one.
1912PHONY += single_modules
1913single_modules: $(single-no-ko) modules_prepare
1914	$(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$(m:%.ko=%.o);) } > $(MODORDER)
1915	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1916ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1917	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1918endif
1919	$(Q)rm -f $(MODORDER)
1920
1921single-goals := $(addprefix $(build-dir)/, $(single-no-ko))
1922
1923KBUILD_MODULES := 1
1924
1925endif
1926
1927# Preset locale variables to speed up the build process. Limit locale
1928# tweaks to this spot to avoid wrong language settings when running
1929# make menuconfig etc.
1930# Error messages still appears in the original language
1931PHONY += $(build-dir)
1932$(build-dir): prepare
1933	$(Q)$(MAKE) $(build)=$@ need-builtin=1 need-modorder=1 $(single-goals)
1934
1935clean-dirs := $(addprefix _clean_, $(clean-dirs))
1936PHONY += $(clean-dirs) clean
1937$(clean-dirs):
1938	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1939
1940clean: $(clean-dirs)
1941	$(call cmd,rmfiles)
1942	@find $(or $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1943		\( -name '*.[aios]' -o -name '*.rsi' -o -name '*.ko' -o -name '.*.cmd' \
1944		-o -name '*.ko.*' \
1945		-o -name '*.dtb' -o -name '*.dtbo' \
1946		-o -name '*.dtb.S' -o -name '*.dtbo.S' \
1947		-o -name '*.dt.yaml' -o -name 'dtbs-list' \
1948		-o -name '*.dwo' -o -name '*.lst' \
1949		-o -name '*.su' -o -name '*.mod' \
1950		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1951		-o -name '*.lex.c' -o -name '*.tab.[ch]' \
1952		-o -name '*.asn1.[ch]' \
1953		-o -name '*.symtypes' -o -name 'modules.order' \
1954		-o -name '*.c.[012]*.*' \
1955		-o -name '*.ll' \
1956		-o -name '*.gcno' \
1957		-o -name '*.*.symversions' \) -type f -print \
1958		-o -name '.tmp_*' -print \
1959		| xargs rm -rf
1960
1961# Generate tags for editors
1962# ---------------------------------------------------------------------------
1963quiet_cmd_tags = GEN     $@
1964      cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1965
1966tags TAGS cscope gtags: FORCE
1967	$(call cmd,tags)
1968
1969# Generate rust-project.json (a file that describes the structure of non-Cargo
1970# Rust projects) for rust-analyzer (an implementation of the Language Server
1971# Protocol).
1972PHONY += rust-analyzer
1973rust-analyzer:
1974	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh
1975	$(Q)$(MAKE) $(build)=rust $@
1976
1977# Script to generate missing namespace dependencies
1978# ---------------------------------------------------------------------------
1979
1980PHONY += nsdeps
1981nsdeps: export KBUILD_NSDEPS=1
1982nsdeps: modules
1983	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1984
1985# Clang Tooling
1986# ---------------------------------------------------------------------------
1987
1988quiet_cmd_gen_compile_commands = GEN     $@
1989      cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
1990
1991$(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
1992	$(if $(KBUILD_EXTMOD),, vmlinux.a $(KBUILD_VMLINUX_LIBS)) \
1993	$(if $(CONFIG_MODULES), $(MODORDER)) FORCE
1994	$(call if_changed,gen_compile_commands)
1995
1996targets += $(extmod_prefix)compile_commands.json
1997
1998PHONY += clang-tidy clang-analyzer
1999
2000ifdef CONFIG_CC_IS_CLANG
2001quiet_cmd_clang_tools = CHECK   $<
2002      cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
2003
2004clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
2005	$(call cmd,clang_tools)
2006else
2007clang-tidy clang-analyzer:
2008	@echo "$@ requires CC=clang" >&2
2009	@false
2010endif
2011
2012# Scripts to check various things for consistency
2013# ---------------------------------------------------------------------------
2014
2015PHONY += includecheck versioncheck coccicheck export_report
2016
2017includecheck:
2018	find $(srctree)/* $(RCS_FIND_IGNORE) \
2019		-name '*.[hcS]' -type f -print | sort \
2020		| xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
2021
2022versioncheck:
2023	find $(srctree)/* $(RCS_FIND_IGNORE) \
2024		-name '*.[hcS]' -type f -print | sort \
2025		| xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
2026
2027coccicheck:
2028	$(Q)$(BASH) $(srctree)/scripts/$@
2029
2030export_report:
2031	$(PERL) $(srctree)/scripts/export_report.pl
2032
2033PHONY += checkstack kernelrelease kernelversion image_name
2034
2035# UML needs a little special treatment here.  It wants to use the host
2036# toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
2037# else wants $(ARCH), including people doing cross-builds, which means
2038# that $(SUBARCH) doesn't work here.
2039ifeq ($(ARCH), um)
2040CHECKSTACK_ARCH := $(SUBARCH)
2041else
2042CHECKSTACK_ARCH := $(ARCH)
2043endif
2044MINSTACKSIZE	?= 100
2045checkstack:
2046	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
2047	$(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH) $(MINSTACKSIZE)
2048
2049kernelrelease:
2050	@$(filechk_kernel.release)
2051
2052kernelversion:
2053	@echo $(KERNELVERSION)
2054
2055image_name:
2056	@echo $(KBUILD_IMAGE)
2057
2058PHONY += run-command
2059run-command:
2060	$(Q)$(KBUILD_RUN_COMMAND)
2061
2062quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
2063      cmd_rmfiles = rm -rf $(rm-files)
2064
2065# read saved command lines for existing targets
2066existing-targets := $(wildcard $(sort $(targets)))
2067
2068-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
2069
2070endif # config-build
2071endif # mixed-build
2072endif # need-sub-make
2073
2074PHONY += FORCE
2075FORCE:
2076
2077# Declare the contents of the PHONY variable as phony.  We keep that
2078# information in a variable so we can use it in if_changed and friends.
2079.PHONY: $(PHONY)
2080