xref: /linux/Makefile (revision 53c5adff34d77166ed69a4e4bdae3694fe961476)
1# SPDX-License-Identifier: GPL-2.0
2VERSION = 6
3PATCHLEVEL = 7
4SUBLEVEL = 0
5EXTRAVERSION = -rc3
6NAME = Hurr durr I'ma ninja sloth
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))
42export abs_srctree := $(realpath $(dir $(this-makefile)))
43export abs_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# Make's built-in functions such as $(abspath ...), $(realpath ...) cannot
194# expand a shell special character '~'. We use a somewhat tedious way here.
195abs_objtree := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) && pwd)
196$(if $(abs_objtree),, \
197     $(error failed to create output directory "$(KBUILD_OUTPUT)"))
198
199# $(realpath ...) resolves symlinks
200abs_objtree := $(realpath $(abs_objtree))
201endif # ifneq ($(KBUILD_OUTPUT),)
202
203ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
204$(error source directory cannot contain spaces or colons)
205endif
206
207ifneq ($(filter 3.%,$(MAKE_VERSION)),)
208# 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
209# We need to invoke sub-make to avoid implicit rules in the top Makefile.
210need-sub-make := 1
211# Cancel implicit rules for this Makefile.
212$(this-makefile): ;
213endif
214
215export sub_make_done := 1
216
217endif # sub_make_done
218
219ifeq ($(abs_objtree),$(CURDIR))
220# Suppress "Entering directory ..." if we are at the final work directory.
221no-print-directory := --no-print-directory
222else
223# Recursion to show "Entering directory ..."
224need-sub-make := 1
225endif
226
227ifeq ($(filter --no-print-directory, $(MAKEFLAGS)),)
228# If --no-print-directory is unset, recurse once again to set it.
229# You may end up recursing into __sub-make twice. This is needed due to the
230# behavior change in GNU Make 4.4.1.
231need-sub-make := 1
232endif
233
234ifeq ($(need-sub-make),1)
235
236PHONY += $(MAKECMDGOALS) __sub-make
237
238$(filter-out $(this-makefile), $(MAKECMDGOALS)) __all: __sub-make
239	@:
240
241# Invoke a second make in the output directory, passing relevant variables
242__sub-make:
243	$(Q)$(MAKE) $(no-print-directory) -C $(abs_objtree) \
244	-f $(abs_srctree)/Makefile $(MAKECMDGOALS)
245
246else # need-sub-make
247
248# We process the rest of the Makefile if this is the final invocation of make
249
250ifeq ($(abs_srctree),$(abs_objtree))
251        # building in the source tree
252        srctree := .
253	building_out_of_srctree :=
254else
255        ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
256                # building in a subdirectory of the source tree
257                srctree := ..
258        else
259                srctree := $(abs_srctree)
260        endif
261	building_out_of_srctree := 1
262endif
263
264ifneq ($(KBUILD_ABS_SRCTREE),)
265srctree := $(abs_srctree)
266endif
267
268objtree		:= .
269VPATH		:= $(srctree)
270
271export building_out_of_srctree srctree objtree VPATH
272
273# To make sure we do not include .config for any of the *config targets
274# catch them early, and hand them over to scripts/kconfig/Makefile
275# It is allowed to specify more targets when calling make, including
276# mixing *config targets and build targets.
277# For example 'make oldconfig all'.
278# Detect when mixed targets is specified, and make a second invocation
279# of make so .config is not included in this case either (for *config).
280
281version_h := include/generated/uapi/linux/version.h
282
283clean-targets := %clean mrproper cleandocs
284no-dot-config-targets := $(clean-targets) \
285			 cscope gtags TAGS tags help% %docs check% coccicheck \
286			 $(version_h) headers headers_% archheaders archscripts \
287			 %asm-generic kernelversion %src-pkg dt_binding_check \
288			 outputmakefile rustavailable rustfmt rustfmtcheck
289no-sync-config-targets := $(no-dot-config-targets) %install modules_sign kernelrelease \
290			  image_name
291single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.rsi %.s %.symtypes %/
292
293config-build	:=
294mixed-build	:=
295need-config	:= 1
296may-sync-config	:= 1
297single-build	:=
298
299ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
300	ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
301		need-config :=
302	endif
303endif
304
305ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
306	ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
307		may-sync-config :=
308	endif
309endif
310
311need-compiler := $(may-sync-config)
312
313ifneq ($(KBUILD_EXTMOD),)
314	may-sync-config :=
315endif
316
317ifeq ($(KBUILD_EXTMOD),)
318        ifneq ($(filter %config,$(MAKECMDGOALS)),)
319		config-build := 1
320                ifneq ($(words $(MAKECMDGOALS)),1)
321			mixed-build := 1
322                endif
323        endif
324endif
325
326# We cannot build single targets and the others at the same time
327ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
328	single-build := 1
329	ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
330		mixed-build := 1
331	endif
332endif
333
334# For "make -j clean all", "make -j mrproper defconfig all", etc.
335ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
336        ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
337		mixed-build := 1
338        endif
339endif
340
341# install and modules_install need also be processed one by one
342ifneq ($(filter install,$(MAKECMDGOALS)),)
343        ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
344		mixed-build := 1
345        endif
346endif
347
348ifdef mixed-build
349# ===========================================================================
350# We're called with mixed targets (*config and build targets).
351# Handle them one by one.
352
353PHONY += $(MAKECMDGOALS) __build_one_by_one
354
355$(MAKECMDGOALS): __build_one_by_one
356	@:
357
358__build_one_by_one:
359	$(Q)set -e; \
360	for i in $(MAKECMDGOALS); do \
361		$(MAKE) -f $(srctree)/Makefile $$i; \
362	done
363
364else # !mixed-build
365
366include $(srctree)/scripts/Kbuild.include
367
368# Read KERNELRELEASE from include/config/kernel.release (if it exists)
369KERNELRELEASE = $(call read-file, include/config/kernel.release)
370KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
371export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
372
373include $(srctree)/scripts/subarch.include
374
375# Cross compiling and selecting different set of gcc/bin-utils
376# ---------------------------------------------------------------------------
377#
378# When performing cross compilation for other architectures ARCH shall be set
379# to the target architecture. (See arch/* for the possibilities).
380# ARCH can be set during invocation of make:
381# make ARCH=arm64
382# Another way is to have ARCH set in the environment.
383# The default ARCH is the host where make is executed.
384
385# CROSS_COMPILE specify the prefix used for all executables used
386# during compilation. Only gcc and related bin-utils executables
387# are prefixed with $(CROSS_COMPILE).
388# CROSS_COMPILE can be set on the command line
389# make CROSS_COMPILE=aarch64-linux-gnu-
390# Alternatively CROSS_COMPILE can be set in the environment.
391# Default value for CROSS_COMPILE is not to prefix executables
392# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
393ARCH		?= $(SUBARCH)
394
395# Architecture as present in compile.h
396UTS_MACHINE 	:= $(ARCH)
397SRCARCH 	:= $(ARCH)
398
399# Additional ARCH settings for x86
400ifeq ($(ARCH),i386)
401        SRCARCH := x86
402endif
403ifeq ($(ARCH),x86_64)
404        SRCARCH := x86
405endif
406
407# Additional ARCH settings for sparc
408ifeq ($(ARCH),sparc32)
409       SRCARCH := sparc
410endif
411ifeq ($(ARCH),sparc64)
412       SRCARCH := sparc
413endif
414
415# Additional ARCH settings for parisc
416ifeq ($(ARCH),parisc64)
417       SRCARCH := parisc
418endif
419
420export cross_compiling :=
421ifneq ($(SRCARCH),$(SUBARCH))
422cross_compiling := 1
423endif
424
425KCONFIG_CONFIG	?= .config
426export KCONFIG_CONFIG
427
428# SHELL used by kbuild
429CONFIG_SHELL := sh
430
431HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
432HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
433HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
434
435ifneq ($(LLVM),)
436ifneq ($(filter %/,$(LLVM)),)
437LLVM_PREFIX := $(LLVM)
438else ifneq ($(filter -%,$(LLVM)),)
439LLVM_SUFFIX := $(LLVM)
440endif
441
442HOSTCC	= $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
443HOSTCXX	= $(LLVM_PREFIX)clang++$(LLVM_SUFFIX)
444else
445HOSTCC	= gcc
446HOSTCXX	= g++
447endif
448HOSTRUSTC = rustc
449HOSTPKG_CONFIG	= pkg-config
450
451KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
452			 -O2 -fomit-frame-pointer -std=gnu11
453KBUILD_USERCFLAGS  := $(KBUILD_USERHOSTCFLAGS) $(USERCFLAGS)
454KBUILD_USERLDFLAGS := $(USERLDFLAGS)
455
456# These flags apply to all Rust code in the tree, including the kernel and
457# host programs.
458export rust_common_flags := --edition=2021 \
459			    -Zbinary_dep_depinfo=y \
460			    -Dunsafe_op_in_unsafe_fn -Drust_2018_idioms \
461			    -Dunreachable_pub -Dnon_ascii_idents \
462			    -Wmissing_docs \
463			    -Drustdoc::missing_crate_level_docs \
464			    -Dclippy::correctness -Dclippy::style \
465			    -Dclippy::suspicious -Dclippy::complexity \
466			    -Dclippy::perf \
467			    -Dclippy::let_unit_value -Dclippy::mut_mut \
468			    -Dclippy::needless_bitwise_bool \
469			    -Dclippy::needless_continue \
470			    -Dclippy::no_mangle_with_rust_abi \
471			    -Wclippy::dbg_macro
472
473KBUILD_HOSTCFLAGS   := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
474KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
475KBUILD_HOSTRUSTFLAGS := $(rust_common_flags) -O -Cstrip=debuginfo \
476			-Zallow-features= $(HOSTRUSTFLAGS)
477KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
478KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
479
480# Make variables (CC, etc...)
481CPP		= $(CC) -E
482ifneq ($(LLVM),)
483CC		= $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
484LD		= $(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX)
485AR		= $(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX)
486NM		= $(LLVM_PREFIX)llvm-nm$(LLVM_SUFFIX)
487OBJCOPY		= $(LLVM_PREFIX)llvm-objcopy$(LLVM_SUFFIX)
488OBJDUMP		= $(LLVM_PREFIX)llvm-objdump$(LLVM_SUFFIX)
489READELF		= $(LLVM_PREFIX)llvm-readelf$(LLVM_SUFFIX)
490STRIP		= $(LLVM_PREFIX)llvm-strip$(LLVM_SUFFIX)
491else
492CC		= $(CROSS_COMPILE)gcc
493LD		= $(CROSS_COMPILE)ld
494AR		= $(CROSS_COMPILE)ar
495NM		= $(CROSS_COMPILE)nm
496OBJCOPY		= $(CROSS_COMPILE)objcopy
497OBJDUMP		= $(CROSS_COMPILE)objdump
498READELF		= $(CROSS_COMPILE)readelf
499STRIP		= $(CROSS_COMPILE)strip
500endif
501RUSTC		= rustc
502RUSTDOC		= rustdoc
503RUSTFMT		= rustfmt
504CLIPPY_DRIVER	= clippy-driver
505BINDGEN		= bindgen
506CARGO		= cargo
507PAHOLE		= pahole
508RESOLVE_BTFIDS	= $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
509LEX		= flex
510YACC		= bison
511AWK		= awk
512INSTALLKERNEL  := installkernel
513PERL		= perl
514PYTHON3		= python3
515CHECK		= sparse
516BASH		= bash
517KGZIP		= gzip
518KBZIP2		= bzip2
519KLZOP		= lzop
520LZMA		= lzma
521LZ4		= lz4c
522XZ		= xz
523ZSTD		= zstd
524
525CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
526		  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
527NOSTDINC_FLAGS :=
528CFLAGS_MODULE   =
529RUSTFLAGS_MODULE =
530AFLAGS_MODULE   =
531LDFLAGS_MODULE  =
532CFLAGS_KERNEL	=
533RUSTFLAGS_KERNEL =
534AFLAGS_KERNEL	=
535LDFLAGS_vmlinux =
536
537# Use USERINCLUDE when you must reference the UAPI directories only.
538USERINCLUDE    := \
539		-I$(srctree)/arch/$(SRCARCH)/include/uapi \
540		-I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
541		-I$(srctree)/include/uapi \
542		-I$(objtree)/include/generated/uapi \
543                -include $(srctree)/include/linux/compiler-version.h \
544                -include $(srctree)/include/linux/kconfig.h
545
546# Use LINUXINCLUDE when you must reference the include/ directory.
547# Needed to be compatible with the O= option
548LINUXINCLUDE    := \
549		-I$(srctree)/arch/$(SRCARCH)/include \
550		-I$(objtree)/arch/$(SRCARCH)/include/generated \
551		$(if $(building_out_of_srctree),-I$(srctree)/include) \
552		-I$(objtree)/include \
553		$(USERINCLUDE)
554
555KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
556
557KBUILD_CFLAGS :=
558KBUILD_CFLAGS += -std=gnu11
559KBUILD_CFLAGS += -fshort-wchar
560KBUILD_CFLAGS += -funsigned-char
561KBUILD_CFLAGS += -fno-common
562KBUILD_CFLAGS += -fno-PIE
563KBUILD_CFLAGS += -fno-strict-aliasing
564
565KBUILD_CPPFLAGS := -D__KERNEL__
566KBUILD_RUSTFLAGS := $(rust_common_flags) \
567		    --target=$(objtree)/scripts/target.json \
568		    -Cpanic=abort -Cembed-bitcode=n -Clto=n \
569		    -Cforce-unwind-tables=n -Ccodegen-units=1 \
570		    -Csymbol-mangling-version=v0 \
571		    -Crelocation-model=static \
572		    -Zfunction-sections=n \
573		    -Dclippy::float_arithmetic
574
575KBUILD_AFLAGS_KERNEL :=
576KBUILD_CFLAGS_KERNEL :=
577KBUILD_RUSTFLAGS_KERNEL :=
578KBUILD_AFLAGS_MODULE  := -DMODULE
579KBUILD_CFLAGS_MODULE  := -DMODULE
580KBUILD_RUSTFLAGS_MODULE := --cfg MODULE
581KBUILD_LDFLAGS_MODULE :=
582KBUILD_LDFLAGS :=
583CLANG_FLAGS :=
584
585ifeq ($(KBUILD_CLIPPY),1)
586	RUSTC_OR_CLIPPY_QUIET := CLIPPY
587	RUSTC_OR_CLIPPY = $(CLIPPY_DRIVER)
588else
589	RUSTC_OR_CLIPPY_QUIET := RUSTC
590	RUSTC_OR_CLIPPY = $(RUSTC)
591endif
592
593ifdef RUST_LIB_SRC
594	export RUST_LIB_SRC
595endif
596
597# Allows the usage of unstable features in stable compilers.
598export RUSTC_BOOTSTRAP := 1
599
600export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG
601export RUSTC RUSTDOC RUSTFMT RUSTC_OR_CLIPPY_QUIET RUSTC_OR_CLIPPY BINDGEN CARGO
602export HOSTRUSTC KBUILD_HOSTRUSTFLAGS
603export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
604export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
605export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
606export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
607export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS
608
609export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
610export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
611export KBUILD_RUSTFLAGS RUSTFLAGS_KERNEL RUSTFLAGS_MODULE
612export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
613export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_RUSTFLAGS_MODULE KBUILD_LDFLAGS_MODULE
614export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL KBUILD_RUSTFLAGS_KERNEL
615
616# Files to ignore in find ... statements
617
618export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
619			  -name CVS -o -name .pc -o -name .hg -o -name .git \) \
620			  -prune -o
621
622# ===========================================================================
623# Rules shared between *config targets and build targets
624
625# Basic helpers built in scripts/basic/
626PHONY += scripts_basic
627scripts_basic:
628	$(Q)$(MAKE) $(build)=scripts/basic
629
630PHONY += outputmakefile
631ifdef building_out_of_srctree
632# Before starting out-of-tree build, make sure the source tree is clean.
633# outputmakefile generates a Makefile in the output directory, if using a
634# separate output directory. This allows convenient use of make in the
635# output directory.
636# At the same time when output Makefile generated, generate .gitignore to
637# ignore whole output directory
638
639quiet_cmd_makefile = GEN     Makefile
640      cmd_makefile = { \
641	echo "\# Automatically generated by $(srctree)/Makefile: don't edit"; \
642	echo "include $(srctree)/Makefile"; \
643	} > Makefile
644
645outputmakefile:
646	@if [ -f $(srctree)/.config -o \
647		 -d $(srctree)/include/config -o \
648		 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
649		echo >&2 "***"; \
650		echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
651		echo >&2 "*** in $(abs_srctree)";\
652		echo >&2 "***"; \
653		false; \
654	fi
655	$(Q)ln -fsn $(srctree) source
656	$(call cmd,makefile)
657	$(Q)test -e .gitignore || \
658	{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
659endif
660
661# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
662# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
663# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
664# and from include/config/auto.conf.cmd to detect the compiler upgrade.
665CC_VERSION_TEXT = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1))
666
667ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
668include $(srctree)/scripts/Makefile.clang
669endif
670
671# Include this also for config targets because some architectures need
672# cc-cross-prefix to determine CROSS_COMPILE.
673ifdef need-compiler
674include $(srctree)/scripts/Makefile.compiler
675endif
676
677ifdef config-build
678# ===========================================================================
679# *config targets only - make sure prerequisites are updated, and descend
680# in scripts/kconfig to make the *config target
681
682# Read arch-specific Makefile to set KBUILD_DEFCONFIG as needed.
683# KBUILD_DEFCONFIG may point out an alternative default configuration
684# used for 'make defconfig'
685include $(srctree)/arch/$(SRCARCH)/Makefile
686export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
687
688config: outputmakefile scripts_basic FORCE
689	$(Q)$(MAKE) $(build)=scripts/kconfig $@
690
691%config: outputmakefile scripts_basic FORCE
692	$(Q)$(MAKE) $(build)=scripts/kconfig $@
693
694else #!config-build
695# ===========================================================================
696# Build targets only - this includes vmlinux, arch-specific targets, clean
697# targets and others. In general all targets except *config targets.
698
699# If building an external module we do not care about the all: rule
700# but instead __all depend on modules
701PHONY += all
702ifeq ($(KBUILD_EXTMOD),)
703__all: all
704else
705__all: modules
706endif
707
708targets :=
709
710# Decide whether to build built-in, modular, or both.
711# Normally, just do built-in.
712
713KBUILD_MODULES :=
714KBUILD_BUILTIN := 1
715
716# If we have only "make modules", don't compile built-in objects.
717ifeq ($(MAKECMDGOALS),modules)
718  KBUILD_BUILTIN :=
719endif
720
721# If we have "make <whatever> modules", compile modules
722# in addition to whatever we do anyway.
723# Just "make" or "make all" shall build modules as well
724
725ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
726  KBUILD_MODULES := 1
727endif
728
729ifeq ($(MAKECMDGOALS),)
730  KBUILD_MODULES := 1
731endif
732
733export KBUILD_MODULES KBUILD_BUILTIN
734
735ifdef need-config
736include include/config/auto.conf
737endif
738
739ifeq ($(KBUILD_EXTMOD),)
740# Objects we will link into vmlinux / subdirs we need to visit
741core-y		:=
742drivers-y	:=
743libs-y		:= lib/
744endif # KBUILD_EXTMOD
745
746# The all: target is the default when no target is given on the
747# command line.
748# This allow a user to issue only 'make' to build a kernel including modules
749# Defaults to vmlinux, but the arch makefile usually adds further targets
750all: vmlinux
751
752CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage
753ifdef CONFIG_CC_IS_GCC
754CFLAGS_GCOV	+= -fno-tree-loop-im
755endif
756export CFLAGS_GCOV
757
758# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
759ifdef CONFIG_FUNCTION_TRACER
760  CC_FLAGS_FTRACE := -pg
761endif
762
763include $(srctree)/arch/$(SRCARCH)/Makefile
764
765ifdef need-config
766ifdef may-sync-config
767# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
768# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
769# because some architectures define CROSS_COMPILE there.
770include include/config/auto.conf.cmd
771
772$(KCONFIG_CONFIG):
773	@echo >&2 '***'
774	@echo >&2 '*** Configuration file "$@" not found!'
775	@echo >&2 '***'
776	@echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
777	@echo >&2 '*** "make menuconfig" or "make xconfig").'
778	@echo >&2 '***'
779	@/bin/false
780
781# The actual configuration files used during the build are stored in
782# include/generated/ and include/config/. Update them if .config is newer than
783# include/config/auto.conf (which mirrors .config).
784#
785# This exploits the 'multi-target pattern rule' trick.
786# The syncconfig should be executed only once to make all the targets.
787# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
788#
789# Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
790# so you cannot notice that Kconfig is waiting for the user input.
791%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h %/generated/rustc_cfg: $(KCONFIG_CONFIG)
792	$(Q)$(kecho) "  SYNC    $@"
793	$(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
794else # !may-sync-config
795# External modules and some install targets need include/generated/autoconf.h
796# and include/config/auto.conf but do not care if they are up-to-date.
797# Use auto.conf to trigger the test
798PHONY += include/config/auto.conf
799
800include/config/auto.conf:
801	@test -e include/generated/autoconf.h -a -e $@ || (		\
802	echo >&2;							\
803	echo >&2 "  ERROR: Kernel configuration is invalid.";		\
804	echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
805	echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";	\
806	echo >&2 ;							\
807	/bin/false)
808
809endif # may-sync-config
810endif # need-config
811
812KBUILD_CFLAGS	+= -fno-delete-null-pointer-checks
813
814ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
815KBUILD_CFLAGS += -O2
816KBUILD_RUSTFLAGS += -Copt-level=2
817else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
818KBUILD_CFLAGS += -Os
819KBUILD_RUSTFLAGS += -Copt-level=s
820endif
821
822# Always set `debug-assertions` and `overflow-checks` because their default
823# depends on `opt-level` and `debug-assertions`, respectively.
824KBUILD_RUSTFLAGS += -Cdebug-assertions=$(if $(CONFIG_RUST_DEBUG_ASSERTIONS),y,n)
825KBUILD_RUSTFLAGS += -Coverflow-checks=$(if $(CONFIG_RUST_OVERFLOW_CHECKS),y,n)
826
827# Tell gcc to never replace conditional load with a non-conditional one
828ifdef CONFIG_CC_IS_GCC
829# gcc-10 renamed --param=allow-store-data-races=0 to
830# -fno-allow-store-data-races.
831KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
832KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
833endif
834
835ifdef CONFIG_READABLE_ASM
836# Disable optimizations that make assembler listings hard to read.
837# reorder blocks reorders the control in the function
838# ipa clone creates specialized cloned functions
839# partial inlining inlines only parts of functions
840KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
841endif
842
843stackp-flags-y                                    := -fno-stack-protector
844stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
845stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
846
847KBUILD_CFLAGS += $(stackp-flags-y)
848
849KBUILD_RUSTFLAGS-$(CONFIG_WERROR) += -Dwarnings
850KBUILD_RUSTFLAGS += $(KBUILD_RUSTFLAGS-y)
851
852ifdef CONFIG_FRAME_POINTER
853KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
854KBUILD_RUSTFLAGS += -Cforce-frame-pointers=y
855else
856# Some targets (ARM with Thumb2, for example), can't be built with frame
857# pointers.  For those, we don't have FUNCTION_TRACER automatically
858# select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
859# incompatible with -fomit-frame-pointer with current GCC, so we don't use
860# -fomit-frame-pointer with FUNCTION_TRACER.
861# In the Rust target specification, "frame-pointer" is set explicitly
862# to "may-omit".
863ifndef CONFIG_FUNCTION_TRACER
864KBUILD_CFLAGS	+= -fomit-frame-pointer
865endif
866endif
867
868# Initialize all stack variables with a 0xAA pattern.
869ifdef CONFIG_INIT_STACK_ALL_PATTERN
870KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
871endif
872
873# Initialize all stack variables with a zero value.
874ifdef CONFIG_INIT_STACK_ALL_ZERO
875KBUILD_CFLAGS	+= -ftrivial-auto-var-init=zero
876ifdef CONFIG_CC_HAS_AUTO_VAR_INIT_ZERO_ENABLER
877# https://github.com/llvm/llvm-project/issues/44842
878CC_AUTO_VAR_INIT_ZERO_ENABLER := -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
879export CC_AUTO_VAR_INIT_ZERO_ENABLER
880KBUILD_CFLAGS	+= $(CC_AUTO_VAR_INIT_ZERO_ENABLER)
881endif
882endif
883
884# While VLAs have been removed, GCC produces unreachable stack probes
885# for the randomize_kstack_offset feature. Disable it for all compilers.
886KBUILD_CFLAGS	+= $(call cc-option, -fno-stack-clash-protection)
887
888# Clear used registers at func exit (to reduce data lifetime and ROP gadgets).
889ifdef CONFIG_ZERO_CALL_USED_REGS
890KBUILD_CFLAGS	+= -fzero-call-used-regs=used-gpr
891endif
892
893ifdef CONFIG_FUNCTION_TRACER
894ifdef CONFIG_FTRACE_MCOUNT_USE_CC
895  CC_FLAGS_FTRACE	+= -mrecord-mcount
896  ifdef CONFIG_HAVE_NOP_MCOUNT
897    ifeq ($(call cc-option-yn, -mnop-mcount),y)
898      CC_FLAGS_FTRACE	+= -mnop-mcount
899      CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
900    endif
901  endif
902endif
903ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
904  ifdef CONFIG_HAVE_OBJTOOL_NOP_MCOUNT
905    CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
906  endif
907endif
908ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
909  ifdef CONFIG_HAVE_C_RECORDMCOUNT
910    BUILD_C_RECORDMCOUNT := y
911    export BUILD_C_RECORDMCOUNT
912  endif
913endif
914ifdef CONFIG_HAVE_FENTRY
915  # s390-linux-gnu-gcc did not support -mfentry until gcc-9.
916  ifeq ($(call cc-option-yn, -mfentry),y)
917    CC_FLAGS_FTRACE	+= -mfentry
918    CC_FLAGS_USING	+= -DCC_USING_FENTRY
919  endif
920endif
921export CC_FLAGS_FTRACE
922KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
923KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
924endif
925
926# We trigger additional mismatches with less inlining
927ifdef CONFIG_DEBUG_SECTION_MISMATCH
928KBUILD_CFLAGS += -fno-inline-functions-called-once
929endif
930
931# `rustc`'s `-Zfunction-sections` applies to data too (as of 1.59.0).
932ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
933KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
934KBUILD_RUSTFLAGS_KERNEL += -Zfunction-sections=y
935LDFLAGS_vmlinux += --gc-sections
936endif
937
938ifdef CONFIG_SHADOW_CALL_STACK
939ifndef CONFIG_DYNAMIC_SCS
940CC_FLAGS_SCS	:= -fsanitize=shadow-call-stack
941KBUILD_CFLAGS	+= $(CC_FLAGS_SCS)
942endif
943export CC_FLAGS_SCS
944endif
945
946ifdef CONFIG_LTO_CLANG
947ifdef CONFIG_LTO_CLANG_THIN
948CC_FLAGS_LTO	:= -flto=thin -fsplit-lto-unit
949KBUILD_LDFLAGS	+= --thinlto-cache-dir=$(extmod_prefix).thinlto-cache
950else
951CC_FLAGS_LTO	:= -flto
952endif
953CC_FLAGS_LTO	+= -fvisibility=hidden
954
955# Limit inlining across translation units to reduce binary size
956KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
957
958# Check for frame size exceeding threshold during prolog/epilog insertion
959# when using lld < 13.0.0.
960ifneq ($(CONFIG_FRAME_WARN),0)
961ifeq ($(call test-lt, $(CONFIG_LLD_VERSION), 130000),y)
962KBUILD_LDFLAGS	+= -plugin-opt=-warn-stack-size=$(CONFIG_FRAME_WARN)
963endif
964endif
965endif
966
967ifdef CONFIG_LTO
968KBUILD_CFLAGS	+= -fno-lto $(CC_FLAGS_LTO)
969KBUILD_AFLAGS	+= -fno-lto
970export CC_FLAGS_LTO
971endif
972
973ifdef CONFIG_CFI_CLANG
974CC_FLAGS_CFI	:= -fsanitize=kcfi
975KBUILD_CFLAGS	+= $(CC_FLAGS_CFI)
976export CC_FLAGS_CFI
977endif
978
979ifneq ($(CONFIG_FUNCTION_ALIGNMENT),0)
980KBUILD_CFLAGS += -falign-functions=$(CONFIG_FUNCTION_ALIGNMENT)
981endif
982
983# arch Makefile may override CC so keep this after arch Makefile is included
984NOSTDINC_FLAGS += -nostdinc
985
986# To gain proper coverage for CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE,
987# the kernel uses only C99 flexible arrays for dynamically sized trailing
988# arrays. Enforce this for everything that may examine structure sizes and
989# perform bounds checking.
990KBUILD_CFLAGS += $(call cc-option, -fstrict-flex-arrays=3)
991
992# disable invalid "can't wrap" optimizations for signed / pointers
993KBUILD_CFLAGS	+= -fno-strict-overflow
994
995# Make sure -fstack-check isn't enabled (like gentoo apparently did)
996KBUILD_CFLAGS  += -fno-stack-check
997
998# conserve stack if available
999ifdef CONFIG_CC_IS_GCC
1000KBUILD_CFLAGS   += -fconserve-stack
1001endif
1002
1003# change __FILE__ to the relative path from the srctree
1004KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
1005
1006# include additional Makefiles when needed
1007include-y			:= scripts/Makefile.extrawarn
1008include-$(CONFIG_DEBUG_INFO)	+= scripts/Makefile.debug
1009include-$(CONFIG_DEBUG_INFO_BTF)+= scripts/Makefile.btf
1010include-$(CONFIG_KASAN)		+= scripts/Makefile.kasan
1011include-$(CONFIG_KCSAN)		+= scripts/Makefile.kcsan
1012include-$(CONFIG_KMSAN)		+= scripts/Makefile.kmsan
1013include-$(CONFIG_UBSAN)		+= scripts/Makefile.ubsan
1014include-$(CONFIG_KCOV)		+= scripts/Makefile.kcov
1015include-$(CONFIG_RANDSTRUCT)	+= scripts/Makefile.randstruct
1016include-$(CONFIG_GCC_PLUGINS)	+= scripts/Makefile.gcc-plugins
1017
1018include $(addprefix $(srctree)/, $(include-y))
1019
1020# scripts/Makefile.gcc-plugins is intentionally included last.
1021# Do not add $(call cc-option,...) below this line. When you build the kernel
1022# from the clean source tree, the GCC plugins do not exist at this point.
1023
1024# Add user supplied CPPFLAGS, AFLAGS, CFLAGS and RUSTFLAGS as the last assignments
1025KBUILD_CPPFLAGS += $(KCPPFLAGS)
1026KBUILD_AFLAGS   += $(KAFLAGS)
1027KBUILD_CFLAGS   += $(KCFLAGS)
1028KBUILD_RUSTFLAGS += $(KRUSTFLAGS)
1029
1030KBUILD_LDFLAGS_MODULE += --build-id=sha1
1031LDFLAGS_vmlinux += --build-id=sha1
1032
1033KBUILD_LDFLAGS	+= -z noexecstack
1034ifeq ($(CONFIG_LD_IS_BFD),y)
1035KBUILD_LDFLAGS	+= $(call ld-option,--no-warn-rwx-segments)
1036endif
1037
1038ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1039LDFLAGS_vmlinux	+= -X
1040endif
1041
1042ifeq ($(CONFIG_RELR),y)
1043# ld.lld before 15 did not support -z pack-relative-relocs.
1044LDFLAGS_vmlinux	+= $(call ld-option,--pack-dyn-relocs=relr,-z pack-relative-relocs)
1045endif
1046
1047# We never want expected sections to be placed heuristically by the
1048# linker. All sections should be explicitly named in the linker script.
1049ifdef CONFIG_LD_ORPHAN_WARN
1050LDFLAGS_vmlinux += --orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL)
1051endif
1052
1053# Align the bit size of userspace programs with the kernel
1054KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1055KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1056
1057# make the checker run with the right architecture
1058CHECKFLAGS += --arch=$(ARCH)
1059
1060# insure the checker run with the right endianness
1061CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1062
1063# the checker needs the correct machine size
1064CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1065
1066# Default kernel image to build when no specific target is given.
1067# KBUILD_IMAGE may be overruled on the command line or
1068# set in the environment
1069# Also any assignments in arch/$(ARCH)/Makefile take precedence over
1070# this default value
1071export KBUILD_IMAGE ?= vmlinux
1072
1073#
1074# INSTALL_PATH specifies where to place the updated kernel and system map
1075# images. Default is /boot, but you can set it to other values
1076export	INSTALL_PATH ?= /boot
1077
1078#
1079# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1080# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1081# an argument if needed. Otherwise it defaults to the kernel install path
1082#
1083export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1084
1085#
1086# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1087# relocations required by build roots.  This is not defined in the
1088# makefile but the argument can be passed to make if needed.
1089#
1090
1091MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1092export MODLIB
1093
1094PHONY += prepare0
1095
1096export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
1097export MODORDER := $(extmod_prefix)modules.order
1098export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
1099
1100ifeq ($(KBUILD_EXTMOD),)
1101
1102build-dir	:= .
1103clean-dirs	:= $(sort . Documentation \
1104		     $(patsubst %/,%,$(filter %/, $(core-) \
1105			$(drivers-) $(libs-))))
1106
1107export ARCH_CORE	:= $(core-y)
1108export ARCH_LIB		:= $(filter %/, $(libs-y))
1109export ARCH_DRIVERS	:= $(drivers-y) $(drivers-m)
1110# Externally visible symbols (used by link-vmlinux.sh)
1111
1112KBUILD_VMLINUX_OBJS := ./built-in.a
1113ifdef CONFIG_MODULES
1114KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1115KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1116else
1117KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1118endif
1119
1120export KBUILD_VMLINUX_LIBS
1121export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1122
1123ifdef CONFIG_TRIM_UNUSED_KSYMS
1124# For the kernel to actually contain only the needed exported symbols,
1125# we have to build modules as well to determine what those symbols are.
1126KBUILD_MODULES := 1
1127endif
1128
1129# '$(AR) mPi' needs 'T' to workaround the bug of llvm-ar <= 14
1130quiet_cmd_ar_vmlinux.a = AR      $@
1131      cmd_ar_vmlinux.a = \
1132	rm -f $@; \
1133	$(AR) cDPrST $@ $(KBUILD_VMLINUX_OBJS); \
1134	$(AR) mPiT $$($(AR) t $@ | sed -n 1p) $@ $$($(AR) t $@ | grep -F -f $(srctree)/scripts/head-object-list.txt)
1135
1136targets += vmlinux.a
1137vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt FORCE
1138	$(call if_changed,ar_vmlinux.a)
1139
1140PHONY += vmlinux_o
1141vmlinux_o: vmlinux.a $(KBUILD_VMLINUX_LIBS)
1142	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o
1143
1144vmlinux.o modules.builtin.modinfo modules.builtin: vmlinux_o
1145	@:
1146
1147PHONY += vmlinux
1148# LDFLAGS_vmlinux in the top Makefile defines linker flags for the top vmlinux,
1149# not for decompressors. LDFLAGS_vmlinux in arch/*/boot/compressed/Makefile is
1150# unrelated; the decompressors just happen to have the same base name,
1151# arch/*/boot/compressed/vmlinux.
1152# Export LDFLAGS_vmlinux only to scripts/Makefile.vmlinux.
1153#
1154# _LDFLAGS_vmlinux is a workaround for the 'private export' bug:
1155#   https://savannah.gnu.org/bugs/?61463
1156# For Make > 4.4, the following simple code will work:
1157#  vmlinux: private export LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1158vmlinux: private _LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1159vmlinux: export LDFLAGS_vmlinux = $(_LDFLAGS_vmlinux)
1160vmlinux: vmlinux.o $(KBUILD_LDS) modpost
1161	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux
1162
1163# The actual objects are generated when descending,
1164# make sure no implicit rule kicks in
1165$(sort $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)): . ;
1166
1167ifeq ($(origin KERNELRELEASE),file)
1168filechk_kernel.release = $(srctree)/scripts/setlocalversion $(srctree)
1169else
1170filechk_kernel.release = echo $(KERNELRELEASE)
1171endif
1172
1173# Store (new) KERNELRELEASE string in include/config/kernel.release
1174include/config/kernel.release: FORCE
1175	$(call filechk,kernel.release)
1176
1177# Additional helpers built in scripts/
1178# Carefully list dependencies so we do not try to build scripts twice
1179# in parallel
1180PHONY += scripts
1181scripts: scripts_basic scripts_dtc
1182	$(Q)$(MAKE) $(build)=$(@)
1183
1184# Things we need to do before we recursively start building the kernel
1185# or the modules are listed in "prepare".
1186# A multi level approach is used. prepareN is processed before prepareN-1.
1187# archprepare is used in arch Makefiles and when processed asm symlink,
1188# version.h and scripts_basic is processed / created.
1189
1190PHONY += prepare archprepare
1191
1192archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1193	asm-generic $(version_h) include/generated/utsrelease.h \
1194	include/generated/compile.h include/generated/autoconf.h remove-stale-files
1195
1196prepare0: archprepare
1197	$(Q)$(MAKE) $(build)=scripts/mod
1198	$(Q)$(MAKE) $(build)=. prepare
1199
1200# All the preparing..
1201prepare: prepare0
1202ifdef CONFIG_RUST
1203	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh
1204	$(Q)$(MAKE) $(build)=rust
1205endif
1206
1207PHONY += remove-stale-files
1208remove-stale-files:
1209	$(Q)$(srctree)/scripts/remove-stale-files
1210
1211# Support for using generic headers in asm-generic
1212asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1213
1214PHONY += asm-generic uapi-asm-generic
1215asm-generic: uapi-asm-generic
1216	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1217	generic=include/asm-generic
1218uapi-asm-generic:
1219	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1220	generic=include/uapi/asm-generic
1221
1222# Generate some files
1223# ---------------------------------------------------------------------------
1224
1225# KERNELRELEASE can change from a few different places, meaning version.h
1226# needs to be updated, so this check is forced on all builds
1227
1228uts_len := 64
1229define filechk_utsrelease.h
1230	if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1231	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1232	  exit 1;                                                         \
1233	fi;                                                               \
1234	echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1235endef
1236
1237define filechk_version.h
1238	if [ $(SUBLEVEL) -gt 255 ]; then                                 \
1239		echo \#define LINUX_VERSION_CODE $(shell                 \
1240		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1241	else                                                             \
1242		echo \#define LINUX_VERSION_CODE $(shell                 \
1243		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1244	fi;                                                              \
1245	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
1246	((c) > 255 ? 255 : (c)))';                                       \
1247	echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
1248	echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
1249	echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1250endef
1251
1252$(version_h): PATCHLEVEL := $(or $(PATCHLEVEL), 0)
1253$(version_h): SUBLEVEL := $(or $(SUBLEVEL), 0)
1254$(version_h): FORCE
1255	$(call filechk,version.h)
1256
1257include/generated/utsrelease.h: include/config/kernel.release FORCE
1258	$(call filechk,utsrelease.h)
1259
1260filechk_compile.h = $(srctree)/scripts/mkcompile_h \
1261	"$(UTS_MACHINE)" "$(CONFIG_CC_VERSION_TEXT)" "$(LD)"
1262
1263include/generated/compile.h: FORCE
1264	$(call filechk,compile.h)
1265
1266PHONY += headerdep
1267headerdep:
1268	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1269	$(srctree)/scripts/headerdep.pl -I$(srctree)/include
1270
1271# ---------------------------------------------------------------------------
1272# Kernel headers
1273
1274#Default location for installed headers
1275export INSTALL_HDR_PATH = $(objtree)/usr
1276
1277quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1278      cmd_headers_install = \
1279	mkdir -p $(INSTALL_HDR_PATH); \
1280	rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1281	usr/include $(INSTALL_HDR_PATH)
1282
1283PHONY += headers_install
1284headers_install: headers
1285	$(call cmd,headers_install)
1286
1287PHONY += archheaders archscripts
1288
1289hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1290
1291PHONY += headers
1292headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1293	$(if $(filter um, $(SRCARCH)), $(error Headers not exportable for UML))
1294	$(Q)$(MAKE) $(hdr-inst)=include/uapi
1295	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1296
1297ifdef CONFIG_HEADERS_INSTALL
1298prepare: headers
1299endif
1300
1301PHONY += scripts_unifdef
1302scripts_unifdef: scripts_basic
1303	$(Q)$(MAKE) $(build)=scripts scripts/unifdef
1304
1305# ---------------------------------------------------------------------------
1306# Install
1307
1308# Many distributions have the custom install script, /sbin/installkernel.
1309# If DKMS is installed, 'make install' will eventually recurse back
1310# to this Makefile to build and install external modules.
1311# Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
1312
1313quiet_cmd_install = INSTALL $(INSTALL_PATH)
1314      cmd_install = unset sub_make_done; $(srctree)/scripts/install.sh
1315
1316# ---------------------------------------------------------------------------
1317# vDSO install
1318
1319PHONY += vdso_install
1320vdso_install: export INSTALL_FILES = $(vdso-install-y)
1321vdso_install:
1322	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vdsoinst
1323
1324# ---------------------------------------------------------------------------
1325# Tools
1326
1327ifdef CONFIG_OBJTOOL
1328prepare: tools/objtool
1329endif
1330
1331ifdef CONFIG_BPF
1332ifdef CONFIG_DEBUG_INFO_BTF
1333prepare: tools/bpf/resolve_btfids
1334endif
1335endif
1336
1337PHONY += resolve_btfids_clean
1338
1339resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1340
1341# tools/bpf/resolve_btfids directory might not exist
1342# in output directory, skip its clean in that case
1343resolve_btfids_clean:
1344ifneq ($(wildcard $(resolve_btfids_O)),)
1345	$(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1346endif
1347
1348# Clear a bunch of variables before executing the submake
1349ifeq ($(quiet),silent_)
1350tools_silent=s
1351endif
1352
1353tools/: FORCE
1354	$(Q)mkdir -p $(objtree)/tools
1355	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1356
1357tools/%: FORCE
1358	$(Q)mkdir -p $(objtree)/tools
1359	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1360
1361# ---------------------------------------------------------------------------
1362# Kernel selftest
1363
1364PHONY += kselftest
1365kselftest: headers
1366	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1367
1368kselftest-%: headers FORCE
1369	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1370
1371PHONY += kselftest-merge
1372kselftest-merge:
1373	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1374	$(Q)find $(srctree)/tools/testing/selftests -name config -o -name config.$(UTS_MACHINE) | \
1375		xargs $(srctree)/scripts/kconfig/merge_config.sh -y -m $(objtree)/.config
1376	$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1377
1378# ---------------------------------------------------------------------------
1379# Devicetree files
1380
1381ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1382dtstree := arch/$(SRCARCH)/boot/dts
1383endif
1384
1385ifneq ($(dtstree),)
1386
1387%.dtb: dtbs_prepare
1388	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1389
1390%.dtbo: dtbs_prepare
1391	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1392
1393PHONY += dtbs dtbs_prepare dtbs_install dtbs_check
1394dtbs: dtbs_prepare
1395	$(Q)$(MAKE) $(build)=$(dtstree)
1396
1397# include/config/kernel.release is actually needed when installing DTBs because
1398# INSTALL_DTBS_PATH contains $(KERNELRELEASE). However, we do not want to make
1399# dtbs_install depend on it as dtbs_install may run as root.
1400dtbs_prepare: include/config/kernel.release scripts_dtc
1401
1402ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1403export CHECK_DTBS=y
1404endif
1405
1406ifneq ($(CHECK_DTBS),)
1407dtbs_prepare: dt_binding_check
1408endif
1409
1410dtbs_check: dtbs
1411
1412dtbs_install:
1413	$(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1414
1415ifdef CONFIG_OF_EARLY_FLATTREE
1416all: dtbs
1417endif
1418
1419endif
1420
1421PHONY += scripts_dtc
1422scripts_dtc: scripts_basic
1423	$(Q)$(MAKE) $(build)=scripts/dtc
1424
1425ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1426export CHECK_DT_BINDING=y
1427endif
1428
1429PHONY += dt_binding_check
1430dt_binding_check: scripts_dtc
1431	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1432
1433PHONY += dt_compatible_check
1434dt_compatible_check: dt_binding_check
1435	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1436
1437# ---------------------------------------------------------------------------
1438# Modules
1439
1440ifdef CONFIG_MODULES
1441
1442# By default, build modules as well
1443
1444all: modules
1445
1446# When we're building modules with modversions, we need to consider
1447# the built-in objects during the descend as well, in order to
1448# make sure the checksums are up to date before we record them.
1449ifdef CONFIG_MODVERSIONS
1450  KBUILD_BUILTIN := 1
1451endif
1452
1453# Build modules
1454#
1455
1456# *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFO_BTF_MODULES
1457# is an exception.
1458ifdef CONFIG_DEBUG_INFO_BTF_MODULES
1459KBUILD_BUILTIN := 1
1460modules: vmlinux
1461endif
1462
1463modules: modules_prepare
1464
1465# Target to prepare building external modules
1466modules_prepare: prepare
1467	$(Q)$(MAKE) $(build)=scripts scripts/module.lds
1468
1469endif # CONFIG_MODULES
1470
1471###
1472# Cleaning is done on three levels.
1473# make clean     Delete most generated files
1474#                Leave enough to build external modules
1475# make mrproper  Delete the current configuration, and all generated files
1476# make distclean Remove editor backup files, patch leftover files and the like
1477
1478# Directories & files removed with 'make clean'
1479CLEAN_FILES += vmlinux.symvers modules-only.symvers \
1480	       modules.builtin modules.builtin.modinfo modules.nsdeps \
1481	       compile_commands.json .thinlto-cache rust/test \
1482	       rust-project.json .vmlinux.objs .vmlinux.export.c
1483
1484# Directories & files removed with 'make mrproper'
1485MRPROPER_FILES += include/config include/generated          \
1486		  arch/$(SRCARCH)/include/generated .objdiff \
1487		  debian snap tar-install \
1488		  .config .config.old .version \
1489		  Module.symvers \
1490		  certs/signing_key.pem \
1491		  certs/x509.genkey \
1492		  vmlinux-gdb.py \
1493		  rpmbuild \
1494		  rust/libmacros.so
1495
1496# clean - Delete most, but leave enough to build external modules
1497#
1498clean: rm-files := $(CLEAN_FILES)
1499
1500PHONY += archclean vmlinuxclean
1501
1502vmlinuxclean:
1503	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1504	$(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1505
1506clean: archclean vmlinuxclean resolve_btfids_clean
1507
1508# mrproper - Delete all generated files, including .config
1509#
1510mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1511mrproper-dirs      := $(addprefix _mrproper_,scripts)
1512
1513PHONY += $(mrproper-dirs) mrproper
1514$(mrproper-dirs):
1515	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1516
1517mrproper: clean $(mrproper-dirs)
1518	$(call cmd,rmfiles)
1519	@find . $(RCS_FIND_IGNORE) \
1520		\( -name '*.rmeta' \) \
1521		-type f -print | xargs rm -f
1522
1523# distclean
1524#
1525PHONY += distclean
1526
1527distclean: mrproper
1528	@find . $(RCS_FIND_IGNORE) \
1529		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1530		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
1531		-o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1532		-o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1533		-type f -print | xargs rm -f
1534
1535
1536# Packaging of the kernel to various formats
1537# ---------------------------------------------------------------------------
1538
1539%src-pkg: FORCE
1540	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1541%pkg: include/config/kernel.release FORCE
1542	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1543
1544# Brief documentation of the typical targets used
1545# ---------------------------------------------------------------------------
1546
1547boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1548boards := $(sort $(notdir $(boards)))
1549board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1550board-dirs := $(sort $(notdir $(board-dirs:/=)))
1551
1552PHONY += help
1553help:
1554	@echo  'Cleaning targets:'
1555	@echo  '  clean		  - Remove most generated files but keep the config and'
1556	@echo  '                    enough build support to build external modules'
1557	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
1558	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
1559	@echo  ''
1560	@$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1561	@echo  ''
1562	@echo  'Other generic targets:'
1563	@echo  '  all		  - Build all targets marked with [*]'
1564	@echo  '* vmlinux	  - Build the bare kernel'
1565	@echo  '* modules	  - Build all modules'
1566	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1567	@echo  '  vdso_install    - Install unstripped vdso to INSTALL_MOD_PATH (default: /)'
1568	@echo  '  dir/            - Build all files in dir and below'
1569	@echo  '  dir/file.[ois]  - Build specified target only'
1570	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1571	@echo  '                    (requires compiler support for LLVM assembly generation)'
1572	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1573	@echo  '                    (requires a recent binutils and recent build (System.map))'
1574	@echo  '  dir/file.ko     - Build module including final link'
1575	@echo  '  modules_prepare - Set up for building external modules'
1576	@echo  '  tags/TAGS	  - Generate tags file for editors'
1577	@echo  '  cscope	  - Generate cscope index'
1578	@echo  '  gtags           - Generate GNU GLOBAL index'
1579	@echo  '  kernelrelease	  - Output the release version string (use with make -s)'
1580	@echo  '  kernelversion	  - Output the version stored in Makefile (use with make -s)'
1581	@echo  '  image_name	  - Output the image name (use with make -s)'
1582	@echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1583	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1584	 echo  ''
1585	@echo  'Static analysers:'
1586	@echo  '  checkstack      - Generate a list of stack hogs'
1587	@echo  '  versioncheck    - Sanity check on version.h usage'
1588	@echo  '  includecheck    - Check for duplicate included header files'
1589	@echo  '  export_report   - List the usages of all exported symbols'
1590	@echo  '  headerdep       - Detect inclusion cycles in headers'
1591	@echo  '  coccicheck      - Check with Coccinelle'
1592	@echo  '  clang-analyzer  - Check with clang static analyzer'
1593	@echo  '  clang-tidy      - Check with clang-tidy'
1594	@echo  ''
1595	@echo  'Tools:'
1596	@echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1597	@echo  ''
1598	@echo  'Kernel selftest:'
1599	@echo  '  kselftest         - Build and run kernel selftest'
1600	@echo  '                      Build, install, and boot kernel before'
1601	@echo  '                      running kselftest on it'
1602	@echo  '                      Run as root for full coverage'
1603	@echo  '  kselftest-all     - Build kernel selftest'
1604	@echo  '  kselftest-install - Build and install kernel selftest'
1605	@echo  '  kselftest-clean   - Remove all generated kselftest files'
1606	@echo  '  kselftest-merge   - Merge all the config dependencies of'
1607	@echo  '		      kselftest to existing .config.'
1608	@echo  ''
1609	@echo  'Rust targets:'
1610	@echo  '  rustavailable   - Checks whether the Rust toolchain is'
1611	@echo  '		    available and, if not, explains why.'
1612	@echo  '  rustfmt	  - Reformat all the Rust code in the kernel'
1613	@echo  '  rustfmtcheck	  - Checks if all the Rust code in the kernel'
1614	@echo  '		    is formatted, printing a diff otherwise.'
1615	@echo  '  rustdoc	  - Generate Rust documentation'
1616	@echo  '		    (requires kernel .config)'
1617	@echo  '  rusttest        - Runs the Rust tests'
1618	@echo  '                    (requires kernel .config; downloads external repos)'
1619	@echo  '  rust-analyzer	  - Generate rust-project.json rust-analyzer support file'
1620	@echo  '		    (requires kernel .config)'
1621	@echo  '  dir/file.[os]   - Build specified target only'
1622	@echo  '  dir/file.rsi    - Build macro expanded source, similar to C preprocessing.'
1623	@echo  '                    Run with RUSTFMT=n to skip reformatting if needed.'
1624	@echo  '                    The output is not intended to be compilable.'
1625	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1626	@echo  ''
1627	@$(if $(dtstree), \
1628		echo 'Devicetree:'; \
1629		echo '* dtbs             - Build device tree blobs for enabled boards'; \
1630		echo '  dtbs_install     - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1631		echo '  dt_binding_check - Validate device tree binding documents'; \
1632		echo '  dtbs_check       - Validate device tree source files';\
1633		echo '')
1634
1635	@echo 'Userspace tools targets:'
1636	@echo '  use "make tools/help"'
1637	@echo '  or  "cd tools; make help"'
1638	@echo  ''
1639	@echo  'Kernel packaging:'
1640	@$(MAKE) -f $(srctree)/scripts/Makefile.package help
1641	@echo  ''
1642	@echo  'Documentation targets:'
1643	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1644	@echo  ''
1645	@echo  'Architecture-specific targets ($(SRCARCH)):'
1646	@$(or $(archhelp),\
1647		echo '  No architecture-specific help defined for $(SRCARCH)')
1648	@echo  ''
1649	@$(if $(boards), \
1650		$(foreach b, $(boards), \
1651		printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1652		echo '')
1653	@$(if $(board-dirs), \
1654		$(foreach b, $(board-dirs), \
1655		printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1656		printf "  %-16s - Show all of the above\\n" help-boards; \
1657		echo '')
1658
1659	@echo  '  make V=n   [targets] 1: verbose build'
1660	@echo  '                       2: give reason for rebuild of target'
1661	@echo  '                       V=1 and V=2 can be combined with V=12'
1662	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1663	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1664	@echo  '                       (sparse by default)'
1665	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1666	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1667	@echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
1668	@echo  '		1: warnings which may be relevant and do not occur too often'
1669	@echo  '		2: warnings which occur quite often but may still be relevant'
1670	@echo  '		3: more obscure warnings, can most likely be ignored'
1671	@echo  '		c: extra checks in the configuration stage (Kconfig)'
1672	@echo  '		e: warnings are being treated as errors'
1673	@echo  '		Multiple levels can be combined with W=12 or W=123'
1674	@$(if $(dtstree), \
1675		echo '  make CHECK_DTBS=1 [targets] Check all generated dtb files against schema'; \
1676		echo '         This can be applied both to "dtbs" and to individual "foo.dtb" targets' ; \
1677		)
1678	@echo  ''
1679	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
1680	@echo  'For further info see the ./README file'
1681
1682
1683help-board-dirs := $(addprefix help-,$(board-dirs))
1684
1685help-boards: $(help-board-dirs)
1686
1687boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1688
1689$(help-board-dirs): help-%:
1690	@echo  'Architecture-specific targets ($(SRCARCH) $*):'
1691	@$(if $(boards-per-dir), \
1692		$(foreach b, $(boards-per-dir), \
1693		printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1694		echo '')
1695
1696
1697# Documentation targets
1698# ---------------------------------------------------------------------------
1699DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1700	       linkcheckdocs dochelp refcheckdocs texinfodocs infodocs
1701PHONY += $(DOC_TARGETS)
1702$(DOC_TARGETS):
1703	$(Q)$(MAKE) $(build)=Documentation $@
1704
1705
1706# Rust targets
1707# ---------------------------------------------------------------------------
1708
1709# "Is Rust available?" target
1710PHONY += rustavailable
1711rustavailable:
1712	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh && echo "Rust is available!"
1713
1714# Documentation target
1715#
1716# Using the singular to avoid running afoul of `no-dot-config-targets`.
1717PHONY += rustdoc
1718rustdoc: prepare
1719	$(Q)$(MAKE) $(build)=rust $@
1720
1721# Testing target
1722PHONY += rusttest
1723rusttest: prepare
1724	$(Q)$(MAKE) $(build)=rust $@
1725
1726# Formatting targets
1727PHONY += rustfmt rustfmtcheck
1728
1729# We skip `rust/alloc` since we want to minimize the diff w.r.t. upstream.
1730#
1731# We match using absolute paths since `find` does not resolve them
1732# when matching, which is a problem when e.g. `srctree` is `..`.
1733# We `grep` afterwards in order to remove the directory entry itself.
1734rustfmt:
1735	$(Q)find $(abs_srctree) -type f -name '*.rs' \
1736		-o -path $(abs_srctree)/rust/alloc -prune \
1737		-o -path $(abs_objtree)/rust/test -prune \
1738		| grep -Fv $(abs_srctree)/rust/alloc \
1739		| grep -Fv $(abs_objtree)/rust/test \
1740		| grep -Fv generated \
1741		| xargs $(RUSTFMT) $(rustfmt_flags)
1742
1743rustfmtcheck: rustfmt_flags = --check
1744rustfmtcheck: rustfmt
1745
1746# Misc
1747# ---------------------------------------------------------------------------
1748
1749PHONY += misc-check
1750misc-check:
1751	$(Q)$(srctree)/scripts/misc-check
1752
1753all: misc-check
1754
1755PHONY += scripts_gdb
1756scripts_gdb: prepare0
1757	$(Q)$(MAKE) $(build)=scripts/gdb
1758	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1759
1760ifdef CONFIG_GDB_SCRIPTS
1761all: scripts_gdb
1762endif
1763
1764else # KBUILD_EXTMOD
1765
1766filechk_kernel.release = echo $(KERNELRELEASE)
1767
1768###
1769# External module support.
1770# When building external modules the kernel used as basis is considered
1771# read-only, and no consistency checks are made and the make
1772# system is not used on the basis kernel. If updates are required
1773# in the basis kernel ordinary make commands (without M=...) must be used.
1774
1775# We are always building only modules.
1776KBUILD_BUILTIN :=
1777KBUILD_MODULES := 1
1778
1779build-dir := $(KBUILD_EXTMOD)
1780
1781compile_commands.json: $(extmod_prefix)compile_commands.json
1782PHONY += compile_commands.json
1783
1784clean-dirs := $(KBUILD_EXTMOD)
1785clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1786	$(KBUILD_EXTMOD)/compile_commands.json $(KBUILD_EXTMOD)/.thinlto-cache
1787
1788PHONY += prepare
1789# now expand this into a simple variable to reduce the cost of shell evaluations
1790prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT)
1791prepare:
1792	@if [ "$(CC_VERSION_TEXT)" != "$(CONFIG_CC_VERSION_TEXT)" ]; then \
1793		echo >&2 "warning: the compiler differs from the one used to build the kernel"; \
1794		echo >&2 "  The kernel was built by: $(CONFIG_CC_VERSION_TEXT)"; \
1795		echo >&2 "  You are using:           $(CC_VERSION_TEXT)"; \
1796	fi
1797
1798PHONY += help
1799help:
1800	@echo  '  Building external modules.'
1801	@echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1802	@echo  ''
1803	@echo  '  modules         - default target, build the module(s)'
1804	@echo  '  modules_install - install the module'
1805	@echo  '  clean           - remove generated files in module directory only'
1806	@echo  '  rust-analyzer	  - generate rust-project.json rust-analyzer support file'
1807	@echo  ''
1808
1809ifndef CONFIG_MODULES
1810modules modules_install: __external_modules_error
1811__external_modules_error:
1812	@echo >&2 '***'
1813	@echo >&2 '*** The present kernel disabled CONFIG_MODULES.'
1814	@echo >&2 '*** You cannot build or install external modules.'
1815	@echo >&2 '***'
1816	@false
1817endif
1818
1819endif # KBUILD_EXTMOD
1820
1821# ---------------------------------------------------------------------------
1822# Modules
1823
1824PHONY += modules modules_install modules_sign modules_prepare
1825
1826modules_install:
1827	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst \
1828	sign-only=$(if $(filter modules_install,$(MAKECMDGOALS)),,y)
1829
1830ifeq ($(CONFIG_MODULE_SIG),y)
1831# modules_sign is a subset of modules_install.
1832# 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1833modules_sign: modules_install
1834	@:
1835else
1836modules_sign:
1837	@echo >&2 '***'
1838	@echo >&2 '*** CONFIG_MODULE_SIG is disabled. You cannot sign modules.'
1839	@echo >&2 '***'
1840	@false
1841endif
1842
1843ifdef CONFIG_MODULES
1844
1845$(MODORDER): $(build-dir)
1846	@:
1847
1848# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
1849# This is solely useful to speed up test compiles.
1850modules: modpost
1851ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1852	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1853endif
1854
1855PHONY += modules_check
1856modules_check: $(MODORDER)
1857	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1858
1859else # CONFIG_MODULES
1860
1861modules:
1862	@:
1863
1864KBUILD_MODULES :=
1865
1866endif # CONFIG_MODULES
1867
1868PHONY += modpost
1869modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \
1870	 $(if $(KBUILD_MODULES), modules_check)
1871	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1872
1873# Single targets
1874# ---------------------------------------------------------------------------
1875# To build individual files in subdirectories, you can do like this:
1876#
1877#   make foo/bar/baz.s
1878#
1879# The supported suffixes for single-target are listed in 'single-targets'
1880#
1881# To build only under specific subdirectories, you can do like this:
1882#
1883#   make foo/bar/baz/
1884
1885ifdef single-build
1886
1887# .ko is special because modpost is needed
1888single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1889single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \
1890		$(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko)))
1891
1892$(single-ko): single_modules
1893	@:
1894$(single-no-ko): $(build-dir)
1895	@:
1896
1897# Remove MODORDER when done because it is not the real one.
1898PHONY += single_modules
1899single_modules: $(single-no-ko) modules_prepare
1900	$(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$(m:%.ko=%.o);) } > $(MODORDER)
1901	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1902ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1903	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1904endif
1905	$(Q)rm -f $(MODORDER)
1906
1907single-goals := $(addprefix $(build-dir)/, $(single-no-ko))
1908
1909KBUILD_MODULES := 1
1910
1911endif
1912
1913# Preset locale variables to speed up the build process. Limit locale
1914# tweaks to this spot to avoid wrong language settings when running
1915# make menuconfig etc.
1916# Error messages still appears in the original language
1917PHONY += $(build-dir)
1918$(build-dir): prepare
1919	$(Q)$(MAKE) $(build)=$@ need-builtin=1 need-modorder=1 $(single-goals)
1920
1921clean-dirs := $(addprefix _clean_, $(clean-dirs))
1922PHONY += $(clean-dirs) clean
1923$(clean-dirs):
1924	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1925
1926clean: $(clean-dirs)
1927	$(call cmd,rmfiles)
1928	@find $(or $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1929		\( -name '*.[aios]' -o -name '*.rsi' -o -name '*.ko' -o -name '.*.cmd' \
1930		-o -name '*.ko.*' \
1931		-o -name '*.dtb' -o -name '*.dtbo' \
1932		-o -name '*.dtb.S' -o -name '*.dtbo.S' \
1933		-o -name '*.dt.yaml' \
1934		-o -name '*.dwo' -o -name '*.lst' \
1935		-o -name '*.su' -o -name '*.mod' \
1936		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1937		-o -name '*.lex.c' -o -name '*.tab.[ch]' \
1938		-o -name '*.asn1.[ch]' \
1939		-o -name '*.symtypes' -o -name 'modules.order' \
1940		-o -name '*.c.[012]*.*' \
1941		-o -name '*.ll' \
1942		-o -name '*.gcno' \
1943		-o -name '*.*.symversions' \) -type f -print \
1944		-o -name '.tmp_*' -print \
1945		| xargs rm -rf
1946
1947# Generate tags for editors
1948# ---------------------------------------------------------------------------
1949quiet_cmd_tags = GEN     $@
1950      cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1951
1952tags TAGS cscope gtags: FORCE
1953	$(call cmd,tags)
1954
1955# IDE support targets
1956PHONY += rust-analyzer
1957rust-analyzer:
1958	$(Q)$(MAKE) $(build)=rust $@
1959
1960# Script to generate missing namespace dependencies
1961# ---------------------------------------------------------------------------
1962
1963PHONY += nsdeps
1964nsdeps: export KBUILD_NSDEPS=1
1965nsdeps: modules
1966	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1967
1968# Clang Tooling
1969# ---------------------------------------------------------------------------
1970
1971quiet_cmd_gen_compile_commands = GEN     $@
1972      cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
1973
1974$(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
1975	$(if $(KBUILD_EXTMOD),, vmlinux.a $(KBUILD_VMLINUX_LIBS)) \
1976	$(if $(CONFIG_MODULES), $(MODORDER)) FORCE
1977	$(call if_changed,gen_compile_commands)
1978
1979targets += $(extmod_prefix)compile_commands.json
1980
1981PHONY += clang-tidy clang-analyzer
1982
1983ifdef CONFIG_CC_IS_CLANG
1984quiet_cmd_clang_tools = CHECK   $<
1985      cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
1986
1987clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
1988	$(call cmd,clang_tools)
1989else
1990clang-tidy clang-analyzer:
1991	@echo "$@ requires CC=clang" >&2
1992	@false
1993endif
1994
1995# Scripts to check various things for consistency
1996# ---------------------------------------------------------------------------
1997
1998PHONY += includecheck versioncheck coccicheck export_report
1999
2000includecheck:
2001	find $(srctree)/* $(RCS_FIND_IGNORE) \
2002		-name '*.[hcS]' -type f -print | sort \
2003		| xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
2004
2005versioncheck:
2006	find $(srctree)/* $(RCS_FIND_IGNORE) \
2007		-name '*.[hcS]' -type f -print | sort \
2008		| xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
2009
2010coccicheck:
2011	$(Q)$(BASH) $(srctree)/scripts/$@
2012
2013export_report:
2014	$(PERL) $(srctree)/scripts/export_report.pl
2015
2016PHONY += checkstack kernelrelease kernelversion image_name
2017
2018# UML needs a little special treatment here.  It wants to use the host
2019# toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
2020# else wants $(ARCH), including people doing cross-builds, which means
2021# that $(SUBARCH) doesn't work here.
2022ifeq ($(ARCH), um)
2023CHECKSTACK_ARCH := $(SUBARCH)
2024else
2025CHECKSTACK_ARCH := $(ARCH)
2026endif
2027checkstack:
2028	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
2029	$(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
2030
2031kernelrelease:
2032	@$(filechk_kernel.release)
2033
2034kernelversion:
2035	@echo $(KERNELVERSION)
2036
2037image_name:
2038	@echo $(KBUILD_IMAGE)
2039
2040PHONY += run-command
2041run-command:
2042	$(Q)$(KBUILD_RUN_COMMAND)
2043
2044quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
2045      cmd_rmfiles = rm -rf $(rm-files)
2046
2047# read saved command lines for existing targets
2048existing-targets := $(wildcard $(sort $(targets)))
2049
2050-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
2051
2052endif # config-build
2053endif # mixed-build
2054endif # need-sub-make
2055
2056PHONY += FORCE
2057FORCE:
2058
2059# Declare the contents of the PHONY variable as phony.  We keep that
2060# information in a variable so we can use it in if_changed and friends.
2061.PHONY: $(PHONY)
2062