xref: /linux/Makefile (revision f8f88aa25a03ce1e0fc8a9842840988b870f0c37)
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 \
465			    -Dnon_ascii_idents \
466			    -Wrust_2018_idioms \
467			    -Wunreachable_pub \
468			    -Wmissing_docs \
469			    -Wrustdoc::missing_crate_level_docs \
470			    -Wclippy::correctness -Wclippy::style \
471			    -Wclippy::suspicious -Wclippy::complexity \
472			    -Wclippy::perf \
473			    -Wclippy::let_unit_value -Wclippy::mut_mut \
474			    -Wclippy::needless_bitwise_bool \
475			    -Wclippy::needless_continue \
476			    -Wclippy::no_mangle_with_rust_abi \
477			    -Wclippy::dbg_macro
478
479KBUILD_HOSTCFLAGS   := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
480KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
481KBUILD_HOSTRUSTFLAGS := $(rust_common_flags) -O -Cstrip=debuginfo \
482			-Zallow-features= $(HOSTRUSTFLAGS)
483KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
484KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
485
486# Make variables (CC, etc...)
487CPP		= $(CC) -E
488ifneq ($(LLVM),)
489CC		= $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
490LD		= $(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX)
491AR		= $(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX)
492NM		= $(LLVM_PREFIX)llvm-nm$(LLVM_SUFFIX)
493OBJCOPY		= $(LLVM_PREFIX)llvm-objcopy$(LLVM_SUFFIX)
494OBJDUMP		= $(LLVM_PREFIX)llvm-objdump$(LLVM_SUFFIX)
495READELF		= $(LLVM_PREFIX)llvm-readelf$(LLVM_SUFFIX)
496STRIP		= $(LLVM_PREFIX)llvm-strip$(LLVM_SUFFIX)
497else
498CC		= $(CROSS_COMPILE)gcc
499LD		= $(CROSS_COMPILE)ld
500AR		= $(CROSS_COMPILE)ar
501NM		= $(CROSS_COMPILE)nm
502OBJCOPY		= $(CROSS_COMPILE)objcopy
503OBJDUMP		= $(CROSS_COMPILE)objdump
504READELF		= $(CROSS_COMPILE)readelf
505STRIP		= $(CROSS_COMPILE)strip
506endif
507RUSTC		= rustc
508RUSTDOC		= rustdoc
509RUSTFMT		= rustfmt
510CLIPPY_DRIVER	= clippy-driver
511BINDGEN		= bindgen
512PAHOLE		= pahole
513RESOLVE_BTFIDS	= $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
514LEX		= flex
515YACC		= bison
516AWK		= awk
517INSTALLKERNEL  := installkernel
518PERL		= perl
519PYTHON3		= python3
520CHECK		= sparse
521BASH		= bash
522KGZIP		= gzip
523KBZIP2		= bzip2
524KLZOP		= lzop
525LZMA		= lzma
526LZ4		= lz4c
527XZ		= xz
528ZSTD		= zstd
529
530CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
531		  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
532NOSTDINC_FLAGS :=
533CFLAGS_MODULE   =
534RUSTFLAGS_MODULE =
535AFLAGS_MODULE   =
536LDFLAGS_MODULE  =
537CFLAGS_KERNEL	=
538RUSTFLAGS_KERNEL =
539AFLAGS_KERNEL	=
540LDFLAGS_vmlinux =
541
542# Use USERINCLUDE when you must reference the UAPI directories only.
543USERINCLUDE    := \
544		-I$(srctree)/arch/$(SRCARCH)/include/uapi \
545		-I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
546		-I$(srctree)/include/uapi \
547		-I$(objtree)/include/generated/uapi \
548                -include $(srctree)/include/linux/compiler-version.h \
549                -include $(srctree)/include/linux/kconfig.h
550
551# Use LINUXINCLUDE when you must reference the include/ directory.
552# Needed to be compatible with the O= option
553LINUXINCLUDE    := \
554		-I$(srctree)/arch/$(SRCARCH)/include \
555		-I$(objtree)/arch/$(SRCARCH)/include/generated \
556		$(if $(building_out_of_srctree),-I$(srctree)/include) \
557		-I$(objtree)/include \
558		$(USERINCLUDE)
559
560KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
561
562KBUILD_CFLAGS :=
563KBUILD_CFLAGS += -std=gnu11
564KBUILD_CFLAGS += -fshort-wchar
565KBUILD_CFLAGS += -funsigned-char
566KBUILD_CFLAGS += -fno-common
567KBUILD_CFLAGS += -fno-PIE
568KBUILD_CFLAGS += -fno-strict-aliasing
569
570KBUILD_CPPFLAGS := -D__KERNEL__
571KBUILD_RUSTFLAGS := $(rust_common_flags) \
572		    -Cpanic=abort -Cembed-bitcode=n -Clto=n \
573		    -Cforce-unwind-tables=n -Ccodegen-units=1 \
574		    -Csymbol-mangling-version=v0 \
575		    -Crelocation-model=static \
576		    -Zfunction-sections=n \
577		    -Wclippy::float_arithmetic
578
579KBUILD_AFLAGS_KERNEL :=
580KBUILD_CFLAGS_KERNEL :=
581KBUILD_RUSTFLAGS_KERNEL :=
582KBUILD_AFLAGS_MODULE  := -DMODULE
583KBUILD_CFLAGS_MODULE  := -DMODULE
584KBUILD_RUSTFLAGS_MODULE := --cfg MODULE
585KBUILD_LDFLAGS_MODULE :=
586KBUILD_LDFLAGS :=
587CLANG_FLAGS :=
588
589ifeq ($(KBUILD_CLIPPY),1)
590	RUSTC_OR_CLIPPY_QUIET := CLIPPY
591	RUSTC_OR_CLIPPY = $(CLIPPY_DRIVER)
592else
593	RUSTC_OR_CLIPPY_QUIET := RUSTC
594	RUSTC_OR_CLIPPY = $(RUSTC)
595endif
596
597ifdef RUST_LIB_SRC
598	export RUST_LIB_SRC
599endif
600
601# Allows the usage of unstable features in stable compilers.
602export RUSTC_BOOTSTRAP := 1
603
604export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG
605export RUSTC RUSTDOC RUSTFMT RUSTC_OR_CLIPPY_QUIET RUSTC_OR_CLIPPY BINDGEN
606export HOSTRUSTC KBUILD_HOSTRUSTFLAGS
607export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
608export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
609export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
610export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
611export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS
612
613export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
614export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
615export KBUILD_RUSTFLAGS RUSTFLAGS_KERNEL RUSTFLAGS_MODULE
616export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
617export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_RUSTFLAGS_MODULE KBUILD_LDFLAGS_MODULE
618export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL KBUILD_RUSTFLAGS_KERNEL
619
620# Files to ignore in find ... statements
621
622export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
623			  -name CVS -o -name .pc -o -name .hg -o -name .git \) \
624			  -prune -o
625
626# ===========================================================================
627# Rules shared between *config targets and build targets
628
629# Basic helpers built in scripts/basic/
630PHONY += scripts_basic
631scripts_basic:
632	$(Q)$(MAKE) $(build)=scripts/basic
633
634PHONY += outputmakefile
635ifdef building_out_of_srctree
636# Before starting out-of-tree build, make sure the source tree is clean.
637# outputmakefile generates a Makefile in the output directory, if using a
638# separate output directory. This allows convenient use of make in the
639# output directory.
640# At the same time when output Makefile generated, generate .gitignore to
641# ignore whole output directory
642
643quiet_cmd_makefile = GEN     Makefile
644      cmd_makefile = { \
645	echo "\# Automatically generated by $(srctree)/Makefile: don't edit"; \
646	echo "include $(srctree)/Makefile"; \
647	} > Makefile
648
649outputmakefile:
650	@if [ -f $(srctree)/.config -o \
651		 -d $(srctree)/include/config -o \
652		 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
653		echo >&2 "***"; \
654		echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
655		echo >&2 "*** in $(abs_srctree)";\
656		echo >&2 "***"; \
657		false; \
658	fi
659	$(Q)ln -fsn $(srctree) source
660	$(call cmd,makefile)
661	$(Q)test -e .gitignore || \
662	{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
663endif
664
665# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
666# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
667# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
668# and from include/config/auto.conf.cmd to detect the compiler upgrade.
669CC_VERSION_TEXT = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1))
670
671ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
672include $(srctree)/scripts/Makefile.clang
673endif
674
675# Include this also for config targets because some architectures need
676# cc-cross-prefix to determine CROSS_COMPILE.
677ifdef need-compiler
678include $(srctree)/scripts/Makefile.compiler
679endif
680
681ifdef config-build
682# ===========================================================================
683# *config targets only - make sure prerequisites are updated, and descend
684# in scripts/kconfig to make the *config target
685
686# Read arch-specific Makefile to set KBUILD_DEFCONFIG as needed.
687# KBUILD_DEFCONFIG may point out an alternative default configuration
688# used for 'make defconfig'
689include $(srctree)/arch/$(SRCARCH)/Makefile
690export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
691
692config: outputmakefile scripts_basic FORCE
693	$(Q)$(MAKE) $(build)=scripts/kconfig $@
694
695%config: outputmakefile scripts_basic FORCE
696	$(Q)$(MAKE) $(build)=scripts/kconfig $@
697
698else #!config-build
699# ===========================================================================
700# Build targets only - this includes vmlinux, arch-specific targets, clean
701# targets and others. In general all targets except *config targets.
702
703# If building an external module we do not care about the all: rule
704# but instead __all depend on modules
705PHONY += all
706ifeq ($(KBUILD_EXTMOD),)
707__all: all
708else
709__all: modules
710endif
711
712targets :=
713
714# Decide whether to build built-in, modular, or both.
715# Normally, just do built-in.
716
717KBUILD_MODULES :=
718KBUILD_BUILTIN := 1
719
720# If we have only "make modules", don't compile built-in objects.
721ifeq ($(MAKECMDGOALS),modules)
722  KBUILD_BUILTIN :=
723endif
724
725# If we have "make <whatever> modules", compile modules
726# in addition to whatever we do anyway.
727# Just "make" or "make all" shall build modules as well
728
729ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
730  KBUILD_MODULES := 1
731endif
732
733ifeq ($(MAKECMDGOALS),)
734  KBUILD_MODULES := 1
735endif
736
737export KBUILD_MODULES KBUILD_BUILTIN
738
739ifdef need-config
740include include/config/auto.conf
741endif
742
743ifeq ($(KBUILD_EXTMOD),)
744# Objects we will link into vmlinux / subdirs we need to visit
745core-y		:=
746drivers-y	:=
747libs-y		:= lib/
748endif # KBUILD_EXTMOD
749
750# The all: target is the default when no target is given on the
751# command line.
752# This allow a user to issue only 'make' to build a kernel including modules
753# Defaults to vmlinux, but the arch makefile usually adds further targets
754all: vmlinux
755
756CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage
757ifdef CONFIG_CC_IS_GCC
758CFLAGS_GCOV	+= -fno-tree-loop-im
759endif
760export CFLAGS_GCOV
761
762# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
763ifdef CONFIG_FUNCTION_TRACER
764  CC_FLAGS_FTRACE := -pg
765endif
766
767include $(srctree)/arch/$(SRCARCH)/Makefile
768
769ifdef need-config
770ifdef may-sync-config
771# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
772# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
773# because some architectures define CROSS_COMPILE there.
774include include/config/auto.conf.cmd
775
776$(KCONFIG_CONFIG):
777	@echo >&2 '***'
778	@echo >&2 '*** Configuration file "$@" not found!'
779	@echo >&2 '***'
780	@echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
781	@echo >&2 '*** "make menuconfig" or "make xconfig").'
782	@echo >&2 '***'
783	@/bin/false
784
785# The actual configuration files used during the build are stored in
786# include/generated/ and include/config/. Update them if .config is newer than
787# include/config/auto.conf (which mirrors .config).
788#
789# This exploits the 'multi-target pattern rule' trick.
790# The syncconfig should be executed only once to make all the targets.
791# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
792#
793# Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
794# so you cannot notice that Kconfig is waiting for the user input.
795%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h %/generated/rustc_cfg: $(KCONFIG_CONFIG)
796	$(Q)$(kecho) "  SYNC    $@"
797	$(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
798else # !may-sync-config
799# External modules and some install targets need include/generated/autoconf.h
800# and include/config/auto.conf but do not care if they are up-to-date.
801# Use auto.conf to trigger the test
802PHONY += include/config/auto.conf
803
804include/config/auto.conf:
805	@test -e include/generated/autoconf.h -a -e $@ || (		\
806	echo >&2;							\
807	echo >&2 "  ERROR: Kernel configuration is invalid.";		\
808	echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
809	echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";	\
810	echo >&2 ;							\
811	/bin/false)
812
813endif # may-sync-config
814endif # need-config
815
816KBUILD_CFLAGS	+= -fno-delete-null-pointer-checks
817
818ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
819KBUILD_CFLAGS += -O2
820KBUILD_RUSTFLAGS += -Copt-level=2
821else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
822KBUILD_CFLAGS += -Os
823KBUILD_RUSTFLAGS += -Copt-level=s
824endif
825
826# Always set `debug-assertions` and `overflow-checks` because their default
827# depends on `opt-level` and `debug-assertions`, respectively.
828KBUILD_RUSTFLAGS += -Cdebug-assertions=$(if $(CONFIG_RUST_DEBUG_ASSERTIONS),y,n)
829KBUILD_RUSTFLAGS += -Coverflow-checks=$(if $(CONFIG_RUST_OVERFLOW_CHECKS),y,n)
830
831# Tell gcc to never replace conditional load with a non-conditional one
832ifdef CONFIG_CC_IS_GCC
833# gcc-10 renamed --param=allow-store-data-races=0 to
834# -fno-allow-store-data-races.
835KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
836KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
837endif
838
839ifdef CONFIG_READABLE_ASM
840# Disable optimizations that make assembler listings hard to read.
841# reorder blocks reorders the control in the function
842# ipa clone creates specialized cloned functions
843# partial inlining inlines only parts of functions
844KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
845endif
846
847stackp-flags-y                                    := -fno-stack-protector
848stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
849stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
850
851KBUILD_CFLAGS += $(stackp-flags-y)
852
853KBUILD_RUSTFLAGS-$(CONFIG_WERROR) += -Dwarnings
854KBUILD_RUSTFLAGS += $(KBUILD_RUSTFLAGS-y)
855
856ifdef CONFIG_FRAME_POINTER
857KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
858KBUILD_RUSTFLAGS += -Cforce-frame-pointers=y
859else
860# Some targets (ARM with Thumb2, for example), can't be built with frame
861# pointers.  For those, we don't have FUNCTION_TRACER automatically
862# select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
863# incompatible with -fomit-frame-pointer with current GCC, so we don't use
864# -fomit-frame-pointer with FUNCTION_TRACER.
865# In the Rust target specification, "frame-pointer" is set explicitly
866# to "may-omit".
867ifndef CONFIG_FUNCTION_TRACER
868KBUILD_CFLAGS	+= -fomit-frame-pointer
869endif
870endif
871
872# Initialize all stack variables with a 0xAA pattern.
873ifdef CONFIG_INIT_STACK_ALL_PATTERN
874KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
875endif
876
877# Initialize all stack variables with a zero value.
878ifdef CONFIG_INIT_STACK_ALL_ZERO
879KBUILD_CFLAGS	+= -ftrivial-auto-var-init=zero
880ifdef CONFIG_CC_HAS_AUTO_VAR_INIT_ZERO_ENABLER
881# https://github.com/llvm/llvm-project/issues/44842
882CC_AUTO_VAR_INIT_ZERO_ENABLER := -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
883export CC_AUTO_VAR_INIT_ZERO_ENABLER
884KBUILD_CFLAGS	+= $(CC_AUTO_VAR_INIT_ZERO_ENABLER)
885endif
886endif
887
888# While VLAs have been removed, GCC produces unreachable stack probes
889# for the randomize_kstack_offset feature. Disable it for all compilers.
890KBUILD_CFLAGS	+= $(call cc-option, -fno-stack-clash-protection)
891
892# Clear used registers at func exit (to reduce data lifetime and ROP gadgets).
893ifdef CONFIG_ZERO_CALL_USED_REGS
894KBUILD_CFLAGS	+= -fzero-call-used-regs=used-gpr
895endif
896
897ifdef CONFIG_FUNCTION_TRACER
898ifdef CONFIG_FTRACE_MCOUNT_USE_CC
899  CC_FLAGS_FTRACE	+= -mrecord-mcount
900  ifdef CONFIG_HAVE_NOP_MCOUNT
901    ifeq ($(call cc-option-yn, -mnop-mcount),y)
902      CC_FLAGS_FTRACE	+= -mnop-mcount
903      CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
904    endif
905  endif
906endif
907ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
908  ifdef CONFIG_HAVE_OBJTOOL_NOP_MCOUNT
909    CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
910  endif
911endif
912ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
913  ifdef CONFIG_HAVE_C_RECORDMCOUNT
914    BUILD_C_RECORDMCOUNT := y
915    export BUILD_C_RECORDMCOUNT
916  endif
917endif
918ifdef CONFIG_HAVE_FENTRY
919  # s390-linux-gnu-gcc did not support -mfentry until gcc-9.
920  ifeq ($(call cc-option-yn, -mfentry),y)
921    CC_FLAGS_FTRACE	+= -mfentry
922    CC_FLAGS_USING	+= -DCC_USING_FENTRY
923  endif
924endif
925export CC_FLAGS_FTRACE
926KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
927KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
928endif
929
930# We trigger additional mismatches with less inlining
931ifdef CONFIG_DEBUG_SECTION_MISMATCH
932KBUILD_CFLAGS += -fno-inline-functions-called-once
933endif
934
935# `rustc`'s `-Zfunction-sections` applies to data too (as of 1.59.0).
936ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
937KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
938KBUILD_RUSTFLAGS_KERNEL += -Zfunction-sections=y
939LDFLAGS_vmlinux += --gc-sections
940endif
941
942ifdef CONFIG_SHADOW_CALL_STACK
943ifndef CONFIG_DYNAMIC_SCS
944CC_FLAGS_SCS	:= -fsanitize=shadow-call-stack
945KBUILD_CFLAGS	+= $(CC_FLAGS_SCS)
946endif
947export CC_FLAGS_SCS
948endif
949
950ifdef CONFIG_LTO_CLANG
951ifdef CONFIG_LTO_CLANG_THIN
952CC_FLAGS_LTO	:= -flto=thin -fsplit-lto-unit
953else
954CC_FLAGS_LTO	:= -flto
955endif
956CC_FLAGS_LTO	+= -fvisibility=hidden
957
958# Limit inlining across translation units to reduce binary size
959KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
960endif
961
962ifdef CONFIG_LTO
963KBUILD_CFLAGS	+= -fno-lto $(CC_FLAGS_LTO)
964KBUILD_AFLAGS	+= -fno-lto
965export CC_FLAGS_LTO
966endif
967
968ifdef CONFIG_CFI_CLANG
969CC_FLAGS_CFI	:= -fsanitize=kcfi
970KBUILD_CFLAGS	+= $(CC_FLAGS_CFI)
971export CC_FLAGS_CFI
972endif
973
974# Architectures can define flags to add/remove for floating-point support
975CC_FLAGS_FPU	+= -D_LINUX_FPU_COMPILATION_UNIT
976export CC_FLAGS_FPU
977export CC_FLAGS_NO_FPU
978
979ifneq ($(CONFIG_FUNCTION_ALIGNMENT),0)
980# Set the minimal function alignment. Use the newer GCC option
981# -fmin-function-alignment if it is available, or fall back to -falign-funtions.
982# See also CONFIG_CC_HAS_SANE_FUNCTION_ALIGNMENT.
983ifdef CONFIG_CC_HAS_MIN_FUNCTION_ALIGNMENT
984KBUILD_CFLAGS += -fmin-function-alignment=$(CONFIG_FUNCTION_ALIGNMENT)
985else
986KBUILD_CFLAGS += -falign-functions=$(CONFIG_FUNCTION_ALIGNMENT)
987endif
988endif
989
990# arch Makefile may override CC so keep this after arch Makefile is included
991NOSTDINC_FLAGS += -nostdinc
992
993# To gain proper coverage for CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE,
994# the kernel uses only C99 flexible arrays for dynamically sized trailing
995# arrays. Enforce this for everything that may examine structure sizes and
996# perform bounds checking.
997KBUILD_CFLAGS += $(call cc-option, -fstrict-flex-arrays=3)
998
999#Currently, disable -Wstringop-overflow for GCC 11, globally.
1000KBUILD_CFLAGS-$(CONFIG_CC_NO_STRINGOP_OVERFLOW) += $(call cc-option, -Wno-stringop-overflow)
1001KBUILD_CFLAGS-$(CONFIG_CC_STRINGOP_OVERFLOW) += $(call cc-option, -Wstringop-overflow)
1002
1003# disable invalid "can't wrap" optimizations for signed / pointers
1004KBUILD_CFLAGS	+= -fno-strict-overflow
1005
1006# Make sure -fstack-check isn't enabled (like gentoo apparently did)
1007KBUILD_CFLAGS  += -fno-stack-check
1008
1009# conserve stack if available
1010ifdef CONFIG_CC_IS_GCC
1011KBUILD_CFLAGS   += -fconserve-stack
1012endif
1013
1014# change __FILE__ to the relative path from the srctree
1015KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
1016
1017# include additional Makefiles when needed
1018include-y			:= scripts/Makefile.extrawarn
1019include-$(CONFIG_DEBUG_INFO)	+= scripts/Makefile.debug
1020include-$(CONFIG_DEBUG_INFO_BTF)+= scripts/Makefile.btf
1021include-$(CONFIG_KASAN)		+= scripts/Makefile.kasan
1022include-$(CONFIG_KCSAN)		+= scripts/Makefile.kcsan
1023include-$(CONFIG_KMSAN)		+= scripts/Makefile.kmsan
1024include-$(CONFIG_UBSAN)		+= scripts/Makefile.ubsan
1025include-$(CONFIG_KCOV)		+= scripts/Makefile.kcov
1026include-$(CONFIG_RANDSTRUCT)	+= scripts/Makefile.randstruct
1027include-$(CONFIG_GCC_PLUGINS)	+= scripts/Makefile.gcc-plugins
1028
1029include $(addprefix $(srctree)/, $(include-y))
1030
1031# scripts/Makefile.gcc-plugins is intentionally included last.
1032# Do not add $(call cc-option,...) below this line. When you build the kernel
1033# from the clean source tree, the GCC plugins do not exist at this point.
1034
1035# Add user supplied CPPFLAGS, AFLAGS, CFLAGS and RUSTFLAGS as the last assignments
1036KBUILD_CPPFLAGS += $(KCPPFLAGS)
1037KBUILD_AFLAGS   += $(KAFLAGS)
1038KBUILD_CFLAGS   += $(KCFLAGS)
1039KBUILD_RUSTFLAGS += $(KRUSTFLAGS)
1040
1041KBUILD_LDFLAGS_MODULE += --build-id=sha1
1042LDFLAGS_vmlinux += --build-id=sha1
1043
1044KBUILD_LDFLAGS	+= -z noexecstack
1045ifeq ($(CONFIG_LD_IS_BFD),y)
1046KBUILD_LDFLAGS	+= $(call ld-option,--no-warn-rwx-segments)
1047endif
1048
1049ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1050LDFLAGS_vmlinux	+= -X
1051endif
1052
1053ifeq ($(CONFIG_RELR),y)
1054# ld.lld before 15 did not support -z pack-relative-relocs.
1055LDFLAGS_vmlinux	+= $(call ld-option,--pack-dyn-relocs=relr,-z pack-relative-relocs)
1056endif
1057
1058# We never want expected sections to be placed heuristically by the
1059# linker. All sections should be explicitly named in the linker script.
1060ifdef CONFIG_LD_ORPHAN_WARN
1061LDFLAGS_vmlinux += --orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL)
1062endif
1063
1064# Align the bit size of userspace programs with the kernel
1065KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1066KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1067
1068# make the checker run with the right architecture
1069CHECKFLAGS += --arch=$(ARCH)
1070
1071# insure the checker run with the right endianness
1072CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1073
1074# the checker needs the correct machine size
1075CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1076
1077# Default kernel image to build when no specific target is given.
1078# KBUILD_IMAGE may be overruled on the command line or
1079# set in the environment
1080# Also any assignments in arch/$(ARCH)/Makefile take precedence over
1081# this default value
1082export KBUILD_IMAGE ?= vmlinux
1083
1084#
1085# INSTALL_PATH specifies where to place the updated kernel and system map
1086# images. Default is /boot, but you can set it to other values
1087export	INSTALL_PATH ?= /boot
1088
1089#
1090# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1091# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1092# an argument if needed. Otherwise it defaults to the kernel install path
1093#
1094export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1095
1096#
1097# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1098# relocations required by build roots.  This is not defined in the
1099# makefile but the argument can be passed to make if needed.
1100#
1101
1102MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1103export MODLIB
1104
1105PHONY += prepare0
1106
1107export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
1108export MODORDER := $(extmod_prefix)modules.order
1109export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
1110
1111ifeq ($(KBUILD_EXTMOD),)
1112
1113build-dir	:= .
1114clean-dirs	:= $(sort . Documentation \
1115		     $(patsubst %/,%,$(filter %/, $(core-) \
1116			$(drivers-) $(libs-))))
1117
1118export ARCH_CORE	:= $(core-y)
1119export ARCH_LIB		:= $(filter %/, $(libs-y))
1120export ARCH_DRIVERS	:= $(drivers-y) $(drivers-m)
1121# Externally visible symbols (used by link-vmlinux.sh)
1122
1123KBUILD_VMLINUX_OBJS := ./built-in.a
1124ifdef CONFIG_MODULES
1125KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1126KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1127else
1128KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1129endif
1130
1131export KBUILD_VMLINUX_LIBS
1132export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1133
1134ifdef CONFIG_TRIM_UNUSED_KSYMS
1135# For the kernel to actually contain only the needed exported symbols,
1136# we have to build modules as well to determine what those symbols are.
1137KBUILD_MODULES := 1
1138endif
1139
1140# '$(AR) mPi' needs 'T' to workaround the bug of llvm-ar <= 14
1141quiet_cmd_ar_vmlinux.a = AR      $@
1142      cmd_ar_vmlinux.a = \
1143	rm -f $@; \
1144	$(AR) cDPrST $@ $(KBUILD_VMLINUX_OBJS); \
1145	$(AR) mPiT $$($(AR) t $@ | sed -n 1p) $@ $$($(AR) t $@ | grep -F -f $(srctree)/scripts/head-object-list.txt)
1146
1147targets += vmlinux.a
1148vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt FORCE
1149	$(call if_changed,ar_vmlinux.a)
1150
1151PHONY += vmlinux_o
1152vmlinux_o: vmlinux.a $(KBUILD_VMLINUX_LIBS)
1153	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o
1154
1155vmlinux.o modules.builtin.modinfo modules.builtin: vmlinux_o
1156	@:
1157
1158PHONY += vmlinux
1159# LDFLAGS_vmlinux in the top Makefile defines linker flags for the top vmlinux,
1160# not for decompressors. LDFLAGS_vmlinux in arch/*/boot/compressed/Makefile is
1161# unrelated; the decompressors just happen to have the same base name,
1162# arch/*/boot/compressed/vmlinux.
1163# Export LDFLAGS_vmlinux only to scripts/Makefile.vmlinux.
1164#
1165# _LDFLAGS_vmlinux is a workaround for the 'private export' bug:
1166#   https://savannah.gnu.org/bugs/?61463
1167# For Make > 4.4, the following simple code will work:
1168#  vmlinux: private export LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1169vmlinux: private _LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1170vmlinux: export LDFLAGS_vmlinux = $(_LDFLAGS_vmlinux)
1171vmlinux: vmlinux.o $(KBUILD_LDS) modpost
1172	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux
1173
1174# The actual objects are generated when descending,
1175# make sure no implicit rule kicks in
1176$(sort $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)): . ;
1177
1178ifeq ($(origin KERNELRELEASE),file)
1179filechk_kernel.release = $(srctree)/scripts/setlocalversion $(srctree)
1180else
1181filechk_kernel.release = echo $(KERNELRELEASE)
1182endif
1183
1184# Store (new) KERNELRELEASE string in include/config/kernel.release
1185include/config/kernel.release: FORCE
1186	$(call filechk,kernel.release)
1187
1188# Additional helpers built in scripts/
1189# Carefully list dependencies so we do not try to build scripts twice
1190# in parallel
1191PHONY += scripts
1192scripts: scripts_basic scripts_dtc
1193	$(Q)$(MAKE) $(build)=$(@)
1194
1195# Things we need to do before we recursively start building the kernel
1196# or the modules are listed in "prepare".
1197# A multi level approach is used. prepareN is processed before prepareN-1.
1198# archprepare is used in arch Makefiles and when processed asm symlink,
1199# version.h and scripts_basic is processed / created.
1200
1201PHONY += prepare archprepare
1202
1203archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1204	asm-generic $(version_h) include/generated/utsrelease.h \
1205	include/generated/compile.h include/generated/autoconf.h remove-stale-files
1206
1207prepare0: archprepare
1208	$(Q)$(MAKE) $(build)=scripts/mod
1209	$(Q)$(MAKE) $(build)=. prepare
1210
1211# All the preparing..
1212prepare: prepare0
1213ifdef CONFIG_RUST
1214	+$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh
1215	$(Q)$(MAKE) $(build)=rust
1216endif
1217
1218PHONY += remove-stale-files
1219remove-stale-files:
1220	$(Q)$(srctree)/scripts/remove-stale-files
1221
1222# Support for using generic headers in asm-generic
1223asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1224
1225PHONY += asm-generic uapi-asm-generic
1226asm-generic: uapi-asm-generic
1227	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1228	generic=include/asm-generic
1229uapi-asm-generic:
1230	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1231	generic=include/uapi/asm-generic
1232
1233# Generate some files
1234# ---------------------------------------------------------------------------
1235
1236# KERNELRELEASE can change from a few different places, meaning version.h
1237# needs to be updated, so this check is forced on all builds
1238
1239uts_len := 64
1240define filechk_utsrelease.h
1241	if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1242	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1243	  exit 1;                                                         \
1244	fi;                                                               \
1245	echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1246endef
1247
1248define filechk_version.h
1249	if [ $(SUBLEVEL) -gt 255 ]; then                                 \
1250		echo \#define LINUX_VERSION_CODE $(shell                 \
1251		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1252	else                                                             \
1253		echo \#define LINUX_VERSION_CODE $(shell                 \
1254		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1255	fi;                                                              \
1256	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
1257	((c) > 255 ? 255 : (c)))';                                       \
1258	echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
1259	echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
1260	echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1261endef
1262
1263$(version_h): private PATCHLEVEL := $(or $(PATCHLEVEL), 0)
1264$(version_h): private SUBLEVEL := $(or $(SUBLEVEL), 0)
1265$(version_h): FORCE
1266	$(call filechk,version.h)
1267
1268include/generated/utsrelease.h: include/config/kernel.release FORCE
1269	$(call filechk,utsrelease.h)
1270
1271filechk_compile.h = $(srctree)/scripts/mkcompile_h \
1272	"$(UTS_MACHINE)" "$(CONFIG_CC_VERSION_TEXT)" "$(LD)"
1273
1274include/generated/compile.h: FORCE
1275	$(call filechk,compile.h)
1276
1277PHONY += headerdep
1278headerdep:
1279	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1280	$(srctree)/scripts/headerdep.pl -I$(srctree)/include
1281
1282# ---------------------------------------------------------------------------
1283# Kernel headers
1284
1285#Default location for installed headers
1286export INSTALL_HDR_PATH = $(objtree)/usr
1287
1288quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1289      cmd_headers_install = \
1290	mkdir -p $(INSTALL_HDR_PATH); \
1291	rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1292	usr/include $(INSTALL_HDR_PATH)
1293
1294PHONY += headers_install
1295headers_install: headers
1296	$(call cmd,headers_install)
1297
1298PHONY += archheaders archscripts
1299
1300hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1301
1302PHONY += headers
1303headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1304	$(if $(filter um, $(SRCARCH)), $(error Headers not exportable for UML))
1305	$(Q)$(MAKE) $(hdr-inst)=include/uapi
1306	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1307
1308ifdef CONFIG_HEADERS_INSTALL
1309prepare: headers
1310endif
1311
1312PHONY += scripts_unifdef
1313scripts_unifdef: scripts_basic
1314	$(Q)$(MAKE) $(build)=scripts scripts/unifdef
1315
1316# ---------------------------------------------------------------------------
1317# Install
1318
1319# Many distributions have the custom install script, /sbin/installkernel.
1320# If DKMS is installed, 'make install' will eventually recurse back
1321# to this Makefile to build and install external modules.
1322# Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
1323
1324quiet_cmd_install = INSTALL $(INSTALL_PATH)
1325      cmd_install = unset sub_make_done; $(srctree)/scripts/install.sh
1326
1327# ---------------------------------------------------------------------------
1328# vDSO install
1329
1330PHONY += vdso_install
1331vdso_install: export INSTALL_FILES = $(vdso-install-y)
1332vdso_install:
1333	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vdsoinst
1334
1335# ---------------------------------------------------------------------------
1336# Tools
1337
1338ifdef CONFIG_OBJTOOL
1339prepare: tools/objtool
1340endif
1341
1342ifdef CONFIG_BPF
1343ifdef CONFIG_DEBUG_INFO_BTF
1344prepare: tools/bpf/resolve_btfids
1345endif
1346endif
1347
1348PHONY += resolve_btfids_clean
1349
1350resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1351
1352# tools/bpf/resolve_btfids directory might not exist
1353# in output directory, skip its clean in that case
1354resolve_btfids_clean:
1355ifneq ($(wildcard $(resolve_btfids_O)),)
1356	$(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1357endif
1358
1359# Clear a bunch of variables before executing the submake
1360ifeq ($(quiet),silent_)
1361tools_silent=s
1362endif
1363
1364tools/: FORCE
1365	$(Q)mkdir -p $(objtree)/tools
1366	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1367
1368tools/%: FORCE
1369	$(Q)mkdir -p $(objtree)/tools
1370	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1371
1372# ---------------------------------------------------------------------------
1373# Kernel selftest
1374
1375PHONY += kselftest
1376kselftest: headers
1377	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1378
1379kselftest-%: headers FORCE
1380	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1381
1382PHONY += kselftest-merge
1383kselftest-merge:
1384	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1385	$(Q)find $(srctree)/tools/testing/selftests -name config -o -name config.$(UTS_MACHINE) | \
1386		xargs $(srctree)/scripts/kconfig/merge_config.sh -y -m $(objtree)/.config
1387	$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1388
1389# ---------------------------------------------------------------------------
1390# Devicetree files
1391
1392ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1393dtstree := arch/$(SRCARCH)/boot/dts
1394endif
1395
1396ifneq ($(dtstree),)
1397
1398%.dtb: dtbs_prepare
1399	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1400
1401%.dtbo: dtbs_prepare
1402	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1403
1404PHONY += dtbs dtbs_prepare dtbs_install dtbs_check
1405dtbs: dtbs_prepare
1406	$(Q)$(MAKE) $(build)=$(dtstree) need-dtbslist=1
1407
1408# include/config/kernel.release is actually needed when installing DTBs because
1409# INSTALL_DTBS_PATH contains $(KERNELRELEASE). However, we do not want to make
1410# dtbs_install depend on it as dtbs_install may run as root.
1411dtbs_prepare: include/config/kernel.release scripts_dtc
1412
1413ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1414export CHECK_DTBS=y
1415endif
1416
1417ifneq ($(CHECK_DTBS),)
1418dtbs_prepare: dt_binding_schemas
1419endif
1420
1421dtbs_check: dtbs
1422
1423dtbs_install:
1424	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.dtbinst obj=$(dtstree)
1425
1426ifdef CONFIG_OF_EARLY_FLATTREE
1427all: dtbs
1428endif
1429
1430endif
1431
1432PHONY += scripts_dtc
1433scripts_dtc: scripts_basic
1434	$(Q)$(MAKE) $(build)=scripts/dtc
1435
1436ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1437export CHECK_DTBS=y
1438endif
1439
1440PHONY += dt_binding_check dt_binding_schemas
1441dt_binding_check: dt_binding_schemas scripts_dtc
1442	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1443
1444dt_binding_schemas:
1445	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1446
1447PHONY += dt_compatible_check
1448dt_compatible_check: dt_binding_schemas
1449	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1450
1451# ---------------------------------------------------------------------------
1452# Modules
1453
1454ifdef CONFIG_MODULES
1455
1456# By default, build modules as well
1457
1458all: modules
1459
1460# When we're building modules with modversions, we need to consider
1461# the built-in objects during the descend as well, in order to
1462# make sure the checksums are up to date before we record them.
1463ifdef CONFIG_MODVERSIONS
1464  KBUILD_BUILTIN := 1
1465endif
1466
1467# Build modules
1468#
1469
1470# *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFO_BTF_MODULES
1471# is an exception.
1472ifdef CONFIG_DEBUG_INFO_BTF_MODULES
1473KBUILD_BUILTIN := 1
1474modules: vmlinux
1475endif
1476
1477modules: modules_prepare
1478
1479# Target to prepare building external modules
1480modules_prepare: prepare
1481	$(Q)$(MAKE) $(build)=scripts scripts/module.lds
1482
1483endif # CONFIG_MODULES
1484
1485###
1486# Cleaning is done on three levels.
1487# make clean     Delete most generated files
1488#                Leave enough to build external modules
1489# make mrproper  Delete the current configuration, and all generated files
1490# make distclean Remove editor backup files, patch leftover files and the like
1491
1492# Directories & files removed with 'make clean'
1493CLEAN_FILES += vmlinux.symvers modules-only.symvers \
1494	       modules.builtin modules.builtin.modinfo modules.nsdeps \
1495	       compile_commands.json rust/test \
1496	       rust-project.json .vmlinux.objs .vmlinux.export.c
1497
1498# Directories & files removed with 'make mrproper'
1499MRPROPER_FILES += include/config include/generated          \
1500		  arch/$(SRCARCH)/include/generated .objdiff \
1501		  debian snap tar-install \
1502		  .config .config.old .version \
1503		  Module.symvers \
1504		  certs/signing_key.pem \
1505		  certs/x509.genkey \
1506		  vmlinux-gdb.py \
1507		  rpmbuild \
1508		  rust/libmacros.so
1509
1510# clean - Delete most, but leave enough to build external modules
1511#
1512clean: private rm-files := $(CLEAN_FILES)
1513
1514PHONY += archclean vmlinuxclean
1515
1516vmlinuxclean:
1517	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1518	$(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1519
1520clean: archclean vmlinuxclean resolve_btfids_clean
1521
1522# mrproper - Delete all generated files, including .config
1523#
1524mrproper: private rm-files := $(MRPROPER_FILES)
1525mrproper-dirs      := $(addprefix _mrproper_,scripts)
1526
1527PHONY += $(mrproper-dirs) mrproper
1528$(mrproper-dirs):
1529	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1530
1531mrproper: clean $(mrproper-dirs)
1532	$(call cmd,rmfiles)
1533	@find . $(RCS_FIND_IGNORE) \
1534		\( -name '*.rmeta' \) \
1535		-type f -print | xargs rm -f
1536
1537# distclean
1538#
1539PHONY += distclean
1540
1541distclean: mrproper
1542	@find . $(RCS_FIND_IGNORE) \
1543		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1544		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
1545		-o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1546		-o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1547		-type f -print | xargs rm -f
1548
1549
1550# Packaging of the kernel to various formats
1551# ---------------------------------------------------------------------------
1552
1553%src-pkg: FORCE
1554	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1555%pkg: include/config/kernel.release FORCE
1556	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1557
1558# Brief documentation of the typical targets used
1559# ---------------------------------------------------------------------------
1560
1561boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1562boards := $(sort $(notdir $(boards)))
1563board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1564board-dirs := $(sort $(notdir $(board-dirs:/=)))
1565
1566PHONY += help
1567help:
1568	@echo  'Cleaning targets:'
1569	@echo  '  clean		  - Remove most generated files but keep the config and'
1570	@echo  '                    enough build support to build external modules'
1571	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
1572	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
1573	@echo  ''
1574	@$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1575	@echo  ''
1576	@echo  'Other generic targets:'
1577	@echo  '  all		  - Build all targets marked with [*]'
1578	@echo  '* vmlinux	  - Build the bare kernel'
1579	@echo  '* modules	  - Build all modules'
1580	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1581	@echo  '  vdso_install    - Install unstripped vdso to INSTALL_MOD_PATH (default: /)'
1582	@echo  '  dir/            - Build all files in dir and below'
1583	@echo  '  dir/file.[ois]  - Build specified target only'
1584	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1585	@echo  '                    (requires compiler support for LLVM assembly generation)'
1586	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1587	@echo  '                    (requires a recent binutils and recent build (System.map))'
1588	@echo  '  dir/file.ko     - Build module including final link'
1589	@echo  '  modules_prepare - Set up for building external modules'
1590	@echo  '  tags/TAGS	  - Generate tags file for editors'
1591	@echo  '  cscope	  - Generate cscope index'
1592	@echo  '  gtags           - Generate GNU GLOBAL index'
1593	@echo  '  kernelrelease	  - Output the release version string (use with make -s)'
1594	@echo  '  kernelversion	  - Output the version stored in Makefile (use with make -s)'
1595	@echo  '  image_name	  - Output the image name (use with make -s)'
1596	@echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1597	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1598	 echo  ''
1599	@echo  'Static analysers:'
1600	@echo  '  checkstack      - Generate a list of stack hogs and consider all functions'
1601	@echo  '                    with a stack size larger than MINSTACKSIZE (default: 100)'
1602	@echo  '  versioncheck    - Sanity check on version.h usage'
1603	@echo  '  includecheck    - Check for duplicate included header files'
1604	@echo  '  export_report   - List the usages of all exported symbols'
1605	@echo  '  headerdep       - Detect inclusion cycles in headers'
1606	@echo  '  coccicheck      - Check with Coccinelle'
1607	@echo  '  clang-analyzer  - Check with clang static analyzer'
1608	@echo  '  clang-tidy      - Check with clang-tidy'
1609	@echo  ''
1610	@echo  'Tools:'
1611	@echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1612	@echo  ''
1613	@echo  'Kernel selftest:'
1614	@echo  '  kselftest         - Build and run kernel selftest'
1615	@echo  '                      Build, install, and boot kernel before'
1616	@echo  '                      running kselftest on it'
1617	@echo  '                      Run as root for full coverage'
1618	@echo  '  kselftest-all     - Build kernel selftest'
1619	@echo  '  kselftest-install - Build and install kernel selftest'
1620	@echo  '  kselftest-clean   - Remove all generated kselftest files'
1621	@echo  '  kselftest-merge   - Merge all the config dependencies of'
1622	@echo  '		      kselftest to existing .config.'
1623	@echo  ''
1624	@echo  'Rust targets:'
1625	@echo  '  rustavailable   - Checks whether the Rust toolchain is'
1626	@echo  '		    available and, if not, explains why.'
1627	@echo  '  rustfmt	  - Reformat all the Rust code in the kernel'
1628	@echo  '  rustfmtcheck	  - Checks if all the Rust code in the kernel'
1629	@echo  '		    is formatted, printing a diff otherwise.'
1630	@echo  '  rustdoc	  - Generate Rust documentation'
1631	@echo  '		    (requires kernel .config)'
1632	@echo  '  rusttest        - Runs the Rust tests'
1633	@echo  '                    (requires kernel .config; downloads external repos)'
1634	@echo  '  rust-analyzer	  - Generate rust-project.json rust-analyzer support file'
1635	@echo  '		    (requires kernel .config)'
1636	@echo  '  dir/file.[os]   - Build specified target only'
1637	@echo  '  dir/file.rsi    - Build macro expanded source, similar to C preprocessing.'
1638	@echo  '                    Run with RUSTFMT=n to skip reformatting if needed.'
1639	@echo  '                    The output is not intended to be compilable.'
1640	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1641	@echo  ''
1642	@$(if $(dtstree), \
1643		echo 'Devicetree:'; \
1644		echo '* dtbs               - Build device tree blobs for enabled boards'; \
1645		echo '  dtbs_install       - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1646		echo '  dt_binding_check   - Validate device tree binding documents and examples'; \
1647		echo '  dt_binding_schema  - Build processed device tree binding schemas'; \
1648		echo '  dtbs_check         - Validate device tree source files';\
1649		echo '')
1650
1651	@echo 'Userspace tools targets:'
1652	@echo '  use "make tools/help"'
1653	@echo '  or  "cd tools; make help"'
1654	@echo  ''
1655	@echo  'Kernel packaging:'
1656	@$(MAKE) -f $(srctree)/scripts/Makefile.package help
1657	@echo  ''
1658	@echo  'Documentation targets:'
1659	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1660	@echo  ''
1661	@echo  'Architecture-specific targets ($(SRCARCH)):'
1662	@$(or $(archhelp),\
1663		echo '  No architecture-specific help defined for $(SRCARCH)')
1664	@echo  ''
1665	@$(if $(boards), \
1666		$(foreach b, $(boards), \
1667		printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1668		echo '')
1669	@$(if $(board-dirs), \
1670		$(foreach b, $(board-dirs), \
1671		printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1672		printf "  %-16s - Show all of the above\\n" help-boards; \
1673		echo '')
1674
1675	@echo  '  make V=n   [targets] 1: verbose build'
1676	@echo  '                       2: give reason for rebuild of target'
1677	@echo  '                       V=1 and V=2 can be combined with V=12'
1678	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1679	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1680	@echo  '                       (sparse by default)'
1681	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1682	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1683	@echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3,c,e where'
1684	@echo  '		1: warnings which may be relevant and do not occur too often'
1685	@echo  '		2: warnings which occur quite often but may still be relevant'
1686	@echo  '		3: more obscure warnings, can most likely be ignored'
1687	@echo  '		c: extra checks in the configuration stage (Kconfig)'
1688	@echo  '		e: warnings are being treated as errors'
1689	@echo  '		Multiple levels can be combined with W=12 or W=123'
1690	@$(if $(dtstree), \
1691		echo '  make CHECK_DTBS=1 [targets] Check all generated dtb files against schema'; \
1692		echo '         This can be applied both to "dtbs" and to individual "foo.dtb" targets' ; \
1693		)
1694	@echo  ''
1695	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
1696	@echo  'For further info see the ./README file'
1697
1698
1699help-board-dirs := $(addprefix help-,$(board-dirs))
1700
1701help-boards: $(help-board-dirs)
1702
1703boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1704
1705$(help-board-dirs): help-%:
1706	@echo  'Architecture-specific targets ($(SRCARCH) $*):'
1707	@$(if $(boards-per-dir), \
1708		$(foreach b, $(boards-per-dir), \
1709		printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1710		echo '')
1711
1712
1713# Documentation targets
1714# ---------------------------------------------------------------------------
1715DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1716	       linkcheckdocs dochelp refcheckdocs texinfodocs infodocs
1717PHONY += $(DOC_TARGETS)
1718$(DOC_TARGETS):
1719	$(Q)$(MAKE) $(build)=Documentation $@
1720
1721
1722# Rust targets
1723# ---------------------------------------------------------------------------
1724
1725# "Is Rust available?" target
1726PHONY += rustavailable
1727rustavailable:
1728	+$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh && echo "Rust is available!"
1729
1730# Documentation target
1731#
1732# Using the singular to avoid running afoul of `no-dot-config-targets`.
1733PHONY += rustdoc
1734rustdoc: prepare
1735	$(Q)$(MAKE) $(build)=rust $@
1736
1737# Testing target
1738PHONY += rusttest
1739rusttest: prepare
1740	$(Q)$(MAKE) $(build)=rust $@
1741
1742# Formatting targets
1743PHONY += rustfmt rustfmtcheck
1744
1745# We skip `rust/alloc` since we want to minimize the diff w.r.t. upstream.
1746#
1747# We match using absolute paths since `find` does not resolve them
1748# when matching, which is a problem when e.g. `srctree` is `..`.
1749# We `grep` afterwards in order to remove the directory entry itself.
1750rustfmt:
1751	$(Q)find $(abs_srctree) -type f -name '*.rs' \
1752		-o -path $(abs_srctree)/rust/alloc -prune \
1753		-o -path $(abs_objtree)/rust/test -prune \
1754		| grep -Fv $(abs_srctree)/rust/alloc \
1755		| grep -Fv $(abs_objtree)/rust/test \
1756		| grep -Fv generated \
1757		| xargs $(RUSTFMT) $(rustfmt_flags)
1758
1759rustfmtcheck: rustfmt_flags = --check
1760rustfmtcheck: rustfmt
1761
1762# Misc
1763# ---------------------------------------------------------------------------
1764
1765PHONY += misc-check
1766misc-check:
1767	$(Q)$(srctree)/scripts/misc-check
1768
1769all: misc-check
1770
1771PHONY += scripts_gdb
1772scripts_gdb: prepare0
1773	$(Q)$(MAKE) $(build)=scripts/gdb
1774	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1775
1776ifdef CONFIG_GDB_SCRIPTS
1777all: scripts_gdb
1778endif
1779
1780else # KBUILD_EXTMOD
1781
1782filechk_kernel.release = echo $(KERNELRELEASE)
1783
1784###
1785# External module support.
1786# When building external modules the kernel used as basis is considered
1787# read-only, and no consistency checks are made and the make
1788# system is not used on the basis kernel. If updates are required
1789# in the basis kernel ordinary make commands (without M=...) must be used.
1790
1791# We are always building only modules.
1792KBUILD_BUILTIN :=
1793KBUILD_MODULES := 1
1794
1795build-dir := $(KBUILD_EXTMOD)
1796
1797compile_commands.json: $(extmod_prefix)compile_commands.json
1798PHONY += compile_commands.json
1799
1800clean-dirs := $(KBUILD_EXTMOD)
1801clean: private rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1802	$(KBUILD_EXTMOD)/compile_commands.json
1803
1804PHONY += prepare
1805# now expand this into a simple variable to reduce the cost of shell evaluations
1806prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT)
1807prepare:
1808	@if [ "$(CC_VERSION_TEXT)" != "$(CONFIG_CC_VERSION_TEXT)" ]; then \
1809		echo >&2 "warning: the compiler differs from the one used to build the kernel"; \
1810		echo >&2 "  The kernel was built by: $(CONFIG_CC_VERSION_TEXT)"; \
1811		echo >&2 "  You are using:           $(CC_VERSION_TEXT)"; \
1812	fi
1813
1814PHONY += help
1815help:
1816	@echo  '  Building external modules.'
1817	@echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1818	@echo  ''
1819	@echo  '  modules         - default target, build the module(s)'
1820	@echo  '  modules_install - install the module'
1821	@echo  '  clean           - remove generated files in module directory only'
1822	@echo  '  rust-analyzer	  - generate rust-project.json rust-analyzer support file'
1823	@echo  ''
1824
1825ifndef CONFIG_MODULES
1826modules modules_install: __external_modules_error
1827__external_modules_error:
1828	@echo >&2 '***'
1829	@echo >&2 '*** The present kernel disabled CONFIG_MODULES.'
1830	@echo >&2 '*** You cannot build or install external modules.'
1831	@echo >&2 '***'
1832	@false
1833endif
1834
1835endif # KBUILD_EXTMOD
1836
1837# ---------------------------------------------------------------------------
1838# Modules
1839
1840PHONY += modules modules_install modules_sign modules_prepare
1841
1842modules_install:
1843	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst \
1844	sign-only=$(if $(filter modules_install,$(MAKECMDGOALS)),,y)
1845
1846ifeq ($(CONFIG_MODULE_SIG),y)
1847# modules_sign is a subset of modules_install.
1848# 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1849modules_sign: modules_install
1850	@:
1851else
1852modules_sign:
1853	@echo >&2 '***'
1854	@echo >&2 '*** CONFIG_MODULE_SIG is disabled. You cannot sign modules.'
1855	@echo >&2 '***'
1856	@false
1857endif
1858
1859ifdef CONFIG_MODULES
1860
1861$(MODORDER): $(build-dir)
1862	@:
1863
1864# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
1865# This is solely useful to speed up test compiles.
1866modules: modpost
1867ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1868	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1869endif
1870
1871PHONY += modules_check
1872modules_check: $(MODORDER)
1873	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1874
1875else # CONFIG_MODULES
1876
1877modules:
1878	@:
1879
1880KBUILD_MODULES :=
1881
1882endif # CONFIG_MODULES
1883
1884PHONY += modpost
1885modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \
1886	 $(if $(KBUILD_MODULES), modules_check)
1887	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1888
1889# Single targets
1890# ---------------------------------------------------------------------------
1891# To build individual files in subdirectories, you can do like this:
1892#
1893#   make foo/bar/baz.s
1894#
1895# The supported suffixes for single-target are listed in 'single-targets'
1896#
1897# To build only under specific subdirectories, you can do like this:
1898#
1899#   make foo/bar/baz/
1900
1901ifdef single-build
1902
1903# .ko is special because modpost is needed
1904single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1905single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \
1906		$(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko)))
1907
1908$(single-ko): single_modules
1909	@:
1910$(single-no-ko): $(build-dir)
1911	@:
1912
1913# Remove MODORDER when done because it is not the real one.
1914PHONY += single_modules
1915single_modules: $(single-no-ko) modules_prepare
1916	$(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$(m:%.ko=%.o);) } > $(MODORDER)
1917	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1918ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1919	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1920endif
1921	$(Q)rm -f $(MODORDER)
1922
1923single-goals := $(addprefix $(build-dir)/, $(single-no-ko))
1924
1925KBUILD_MODULES := 1
1926
1927endif
1928
1929# Preset locale variables to speed up the build process. Limit locale
1930# tweaks to this spot to avoid wrong language settings when running
1931# make menuconfig etc.
1932# Error messages still appears in the original language
1933PHONY += $(build-dir)
1934$(build-dir): prepare
1935	$(Q)$(MAKE) $(build)=$@ need-builtin=1 need-modorder=1 $(single-goals)
1936
1937clean-dirs := $(addprefix _clean_, $(clean-dirs))
1938PHONY += $(clean-dirs) clean
1939$(clean-dirs):
1940	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1941
1942clean: $(clean-dirs)
1943	$(call cmd,rmfiles)
1944	@find $(or $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1945		\( -name '*.[aios]' -o -name '*.rsi' -o -name '*.ko' -o -name '.*.cmd' \
1946		-o -name '*.ko.*' \
1947		-o -name '*.dtb' -o -name '*.dtbo' \
1948		-o -name '*.dtb.S' -o -name '*.dtbo.S' \
1949		-o -name '*.dt.yaml' -o -name 'dtbs-list' \
1950		-o -name '*.dwo' -o -name '*.lst' \
1951		-o -name '*.su' -o -name '*.mod' \
1952		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1953		-o -name '*.lex.c' -o -name '*.tab.[ch]' \
1954		-o -name '*.asn1.[ch]' \
1955		-o -name '*.symtypes' -o -name 'modules.order' \
1956		-o -name '*.c.[012]*.*' \
1957		-o -name '*.ll' \
1958		-o -name '*.gcno' \
1959		-o -name '*.*.symversions' \) -type f -print \
1960		-o -name '.tmp_*' -print \
1961		| xargs rm -rf
1962
1963# Generate tags for editors
1964# ---------------------------------------------------------------------------
1965quiet_cmd_tags = GEN     $@
1966      cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1967
1968tags TAGS cscope gtags: FORCE
1969	$(call cmd,tags)
1970
1971# Generate rust-project.json (a file that describes the structure of non-Cargo
1972# Rust projects) for rust-analyzer (an implementation of the Language Server
1973# Protocol).
1974PHONY += rust-analyzer
1975rust-analyzer:
1976	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh
1977	$(Q)$(MAKE) $(build)=rust $@
1978
1979# Script to generate missing namespace dependencies
1980# ---------------------------------------------------------------------------
1981
1982PHONY += nsdeps
1983nsdeps: export KBUILD_NSDEPS=1
1984nsdeps: modules
1985	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1986
1987# Clang Tooling
1988# ---------------------------------------------------------------------------
1989
1990quiet_cmd_gen_compile_commands = GEN     $@
1991      cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
1992
1993$(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
1994	$(if $(KBUILD_EXTMOD),, vmlinux.a $(KBUILD_VMLINUX_LIBS)) \
1995	$(if $(CONFIG_MODULES), $(MODORDER)) FORCE
1996	$(call if_changed,gen_compile_commands)
1997
1998targets += $(extmod_prefix)compile_commands.json
1999
2000PHONY += clang-tidy clang-analyzer
2001
2002ifdef CONFIG_CC_IS_CLANG
2003quiet_cmd_clang_tools = CHECK   $<
2004      cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
2005
2006clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
2007	$(call cmd,clang_tools)
2008else
2009clang-tidy clang-analyzer:
2010	@echo "$@ requires CC=clang" >&2
2011	@false
2012endif
2013
2014# Scripts to check various things for consistency
2015# ---------------------------------------------------------------------------
2016
2017PHONY += includecheck versioncheck coccicheck export_report
2018
2019includecheck:
2020	find $(srctree)/* $(RCS_FIND_IGNORE) \
2021		-name '*.[hcS]' -type f -print | sort \
2022		| xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
2023
2024versioncheck:
2025	find $(srctree)/* $(RCS_FIND_IGNORE) \
2026		-name '*.[hcS]' -type f -print | sort \
2027		| xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
2028
2029coccicheck:
2030	$(Q)$(BASH) $(srctree)/scripts/$@
2031
2032export_report:
2033	$(PERL) $(srctree)/scripts/export_report.pl
2034
2035PHONY += checkstack kernelrelease kernelversion image_name
2036
2037# UML needs a little special treatment here.  It wants to use the host
2038# toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
2039# else wants $(ARCH), including people doing cross-builds, which means
2040# that $(SUBARCH) doesn't work here.
2041ifeq ($(ARCH), um)
2042CHECKSTACK_ARCH := $(SUBARCH)
2043else
2044CHECKSTACK_ARCH := $(ARCH)
2045endif
2046MINSTACKSIZE	?= 100
2047checkstack:
2048	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
2049	$(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH) $(MINSTACKSIZE)
2050
2051kernelrelease:
2052	@$(filechk_kernel.release)
2053
2054kernelversion:
2055	@echo $(KERNELVERSION)
2056
2057image_name:
2058	@echo $(KBUILD_IMAGE)
2059
2060PHONY += run-command
2061run-command:
2062	$(Q)$(KBUILD_RUN_COMMAND)
2063
2064quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
2065      cmd_rmfiles = rm -rf $(rm-files)
2066
2067# read saved command lines for existing targets
2068existing-targets := $(wildcard $(sort $(targets)))
2069
2070-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
2071
2072endif # config-build
2073endif # mixed-build
2074endif # need-sub-make
2075
2076PHONY += FORCE
2077FORCE:
2078
2079# Declare the contents of the PHONY variable as phony.  We keep that
2080# information in a variable so we can use it in if_changed and friends.
2081.PHONY: $(PHONY)
2082