xref: /openbmc/linux/Makefile (revision 5efb685b)
1# SPDX-License-Identifier: GPL-2.0
2VERSION = 6
3PATCHLEVEL = 3
4SUBLEVEL = 0
5EXTRAVERSION = -rc5
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	$(error targets prefixed with '__' are only for internal use))
20
21# That's our default target when none is given on the command line
22PHONY := __all
23__all:
24
25# We are using a recursive build, so we need to do a little thinking
26# to get the ordering right.
27#
28# Most importantly: sub-Makefiles should only ever modify files in
29# their own directory. If in some directory we have a dependency on
30# a file in another dir (which doesn't happen often, but it's often
31# unavoidable when linking the built-in.a targets which finally
32# turn into vmlinux), we will call a sub make in that other dir, and
33# after that we are sure that everything which is in that other dir
34# is now up to date.
35#
36# The only cases where we need to modify files which have global
37# effects are thus separated out and done before the recursive
38# descending is started. They are now explicitly listed as the
39# prepare rule.
40
41ifneq ($(sub_make_done),1)
42
43# Do not use make's built-in rules and variables
44# (this increases performance and avoids hard-to-debug behaviour)
45MAKEFLAGS += -rR
46
47# Avoid funny character set dependencies
48unexport LC_ALL
49LC_COLLATE=C
50LC_NUMERIC=C
51export LC_COLLATE LC_NUMERIC
52
53# Avoid interference with shell env settings
54unexport GREP_OPTIONS
55
56# Beautify output
57# ---------------------------------------------------------------------------
58#
59# Most of build commands in Kbuild start with "cmd_". You can optionally define
60# "quiet_cmd_*". If defined, the short log is printed. Otherwise, no log from
61# that command is printed by default.
62#
63# e.g.)
64#    quiet_cmd_depmod = DEPMOD  $(MODLIB)
65#          cmd_depmod = $(srctree)/scripts/depmod.sh $(DEPMOD) $(KERNELRELEASE)
66#
67# A simple variant is to prefix commands with $(Q) - that's useful
68# for commands that shall be hidden in non-verbose mode.
69#
70#    $(Q)$(MAKE) $(build)=scripts/basic
71#
72# If KBUILD_VERBOSE contains 1, the whole command is echoed.
73# If KBUILD_VERBOSE contains 2, the reason for rebuilding is printed.
74#
75# To put more focus on warnings, be less verbose as default
76# Use 'make V=1' to see the full commands
77
78ifeq ("$(origin V)", "command line")
79  KBUILD_VERBOSE = $(V)
80endif
81
82quiet = quiet_
83Q = @
84
85ifneq ($(findstring 1, $(KBUILD_VERBOSE)),)
86  quiet =
87  Q =
88endif
89
90# If the user is running make -s (silent mode), suppress echoing of
91# commands
92# make-4.0 (and later) keep single letter options in the 1st word of MAKEFLAGS.
93
94ifeq ($(filter 3.%,$(MAKE_VERSION)),)
95short-opts := $(firstword -$(MAKEFLAGS))
96else
97short-opts := $(filter-out --%,$(MAKEFLAGS))
98endif
99
100ifneq ($(findstring s,$(short-opts)),)
101quiet=silent_
102override KBUILD_VERBOSE :=
103endif
104
105export quiet Q KBUILD_VERBOSE
106
107# Call a source code checker (by default, "sparse") as part of the
108# C compilation.
109#
110# Use 'make C=1' to enable checking of only re-compiled files.
111# Use 'make C=2' to enable checking of *all* source files, regardless
112# of whether they are re-compiled or not.
113#
114# See the file "Documentation/dev-tools/sparse.rst" for more details,
115# including where to get the "sparse" utility.
116
117ifeq ("$(origin C)", "command line")
118  KBUILD_CHECKSRC = $(C)
119endif
120ifndef KBUILD_CHECKSRC
121  KBUILD_CHECKSRC = 0
122endif
123
124export KBUILD_CHECKSRC
125
126# Enable "clippy" (a linter) as part of the Rust compilation.
127#
128# Use 'make CLIPPY=1' to enable it.
129ifeq ("$(origin CLIPPY)", "command line")
130  KBUILD_CLIPPY := $(CLIPPY)
131endif
132
133export KBUILD_CLIPPY
134
135# Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
136# directory of external module to build. Setting M= takes precedence.
137ifeq ("$(origin M)", "command line")
138  KBUILD_EXTMOD := $(M)
139endif
140
141$(if $(word 2, $(KBUILD_EXTMOD)), \
142	$(error building multiple external modules is not supported))
143
144$(foreach x, % :, $(if $(findstring $x, $(KBUILD_EXTMOD)), \
145	$(error module directory path cannot contain '$x')))
146
147# Remove trailing slashes
148ifneq ($(filter %/, $(KBUILD_EXTMOD)),)
149KBUILD_EXTMOD := $(shell dirname $(KBUILD_EXTMOD).)
150endif
151
152export KBUILD_EXTMOD
153
154# Kbuild will save output files in the current working directory.
155# This does not need to match to the root of the kernel source tree.
156#
157# For example, you can do this:
158#
159#  cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
160#
161# If you want to save output files in a different location, there are
162# two syntaxes to specify it.
163#
164# 1) O=
165# Use "make O=dir/to/store/output/files/"
166#
167# 2) Set KBUILD_OUTPUT
168# Set the environment variable KBUILD_OUTPUT to point to the output directory.
169# export KBUILD_OUTPUT=dir/to/store/output/files/; make
170#
171# The O= assignment takes precedence over the KBUILD_OUTPUT environment
172# variable.
173
174# Do we want to change the working directory?
175ifeq ("$(origin O)", "command line")
176  KBUILD_OUTPUT := $(O)
177endif
178
179ifneq ($(KBUILD_OUTPUT),)
180# Make's built-in functions such as $(abspath ...), $(realpath ...) cannot
181# expand a shell special character '~'. We use a somewhat tedious way here.
182abs_objtree := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) && pwd)
183$(if $(abs_objtree),, \
184     $(error failed to create output directory "$(KBUILD_OUTPUT)"))
185
186# $(realpath ...) resolves symlinks
187abs_objtree := $(realpath $(abs_objtree))
188else
189abs_objtree := $(CURDIR)
190endif # ifneq ($(KBUILD_OUTPUT),)
191
192ifeq ($(abs_objtree),$(CURDIR))
193# Suppress "Entering directory ..." unless we are changing the work directory.
194MAKEFLAGS += --no-print-directory
195else
196need-sub-make := 1
197endif
198
199this-makefile := $(lastword $(MAKEFILE_LIST))
200abs_srctree := $(realpath $(dir $(this-makefile)))
201
202ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
203$(error source directory cannot contain spaces or colons)
204endif
205
206ifneq ($(filter 3.%,$(MAKE_VERSION)),)
207# 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
208# We need to invoke sub-make to avoid implicit rules in the top Makefile.
209need-sub-make := 1
210# Cancel implicit rules for this Makefile.
211$(this-makefile): ;
212endif
213
214export abs_srctree abs_objtree
215export sub_make_done := 1
216
217ifeq ($(need-sub-make),1)
218
219PHONY += $(MAKECMDGOALS) __sub-make
220
221$(filter-out $(this-makefile), $(MAKECMDGOALS)) __all: __sub-make
222	@:
223
224# Invoke a second make in the output directory, passing relevant variables
225__sub-make:
226	$(Q)$(MAKE) -C $(abs_objtree) -f $(abs_srctree)/Makefile $(MAKECMDGOALS)
227
228endif # need-sub-make
229endif # sub_make_done
230
231# We process the rest of the Makefile if this is the final invocation of make
232ifeq ($(need-sub-make),)
233
234# Do not print "Entering directory ...",
235# but we want to display it when entering to the output directory
236# so that IDEs/editors are able to understand relative filenames.
237MAKEFLAGS += --no-print-directory
238
239ifeq ($(abs_srctree),$(abs_objtree))
240        # building in the source tree
241        srctree := .
242	building_out_of_srctree :=
243else
244        ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
245                # building in a subdirectory of the source tree
246                srctree := ..
247        else
248                srctree := $(abs_srctree)
249        endif
250	building_out_of_srctree := 1
251endif
252
253ifneq ($(KBUILD_ABS_SRCTREE),)
254srctree := $(abs_srctree)
255endif
256
257objtree		:= .
258VPATH		:= $(srctree)
259
260export building_out_of_srctree srctree objtree VPATH
261
262# To make sure we do not include .config for any of the *config targets
263# catch them early, and hand them over to scripts/kconfig/Makefile
264# It is allowed to specify more targets when calling make, including
265# mixing *config targets and build targets.
266# For example 'make oldconfig all'.
267# Detect when mixed targets is specified, and make a second invocation
268# of make so .config is not included in this case either (for *config).
269
270version_h := include/generated/uapi/linux/version.h
271
272clean-targets := %clean mrproper cleandocs
273no-dot-config-targets := $(clean-targets) \
274			 cscope gtags TAGS tags help% %docs check% coccicheck \
275			 $(version_h) headers headers_% archheaders archscripts \
276			 %asm-generic kernelversion %src-pkg dt_binding_check \
277			 outputmakefile rustavailable rustfmt rustfmtcheck
278# Installation targets should not require compiler. Unfortunately, vdso_install
279# is an exception where build artifacts may be updated. This must be fixed.
280no-compiler-targets := $(no-dot-config-targets) install dtbs_install \
281			headers_install modules_install kernelrelease image_name
282no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease \
283			  image_name
284single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.rsi %.s %.symtypes %/
285
286config-build	:=
287mixed-build	:=
288need-config	:= 1
289need-compiler	:= 1
290may-sync-config	:= 1
291single-build	:=
292
293ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
294	ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
295		need-config :=
296	endif
297endif
298
299ifneq ($(filter $(no-compiler-targets), $(MAKECMDGOALS)),)
300	ifeq ($(filter-out $(no-compiler-targets), $(MAKECMDGOALS)),)
301		need-compiler :=
302	endif
303endif
304
305ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
306	ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
307		may-sync-config :=
308	endif
309endif
310
311ifneq ($(KBUILD_EXTMOD),)
312	may-sync-config :=
313endif
314
315ifeq ($(KBUILD_EXTMOD),)
316        ifneq ($(filter %config,$(MAKECMDGOALS)),)
317		config-build := 1
318                ifneq ($(words $(MAKECMDGOALS)),1)
319			mixed-build := 1
320                endif
321        endif
322endif
323
324# We cannot build single targets and the others at the same time
325ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
326	single-build := 1
327	ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
328		mixed-build := 1
329	endif
330endif
331
332# For "make -j clean all", "make -j mrproper defconfig all", etc.
333ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
334        ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
335		mixed-build := 1
336        endif
337endif
338
339# install and modules_install need also be processed one by one
340ifneq ($(filter install,$(MAKECMDGOALS)),)
341        ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
342		mixed-build := 1
343        endif
344endif
345
346ifdef mixed-build
347# ===========================================================================
348# We're called with mixed targets (*config and build targets).
349# Handle them one by one.
350
351PHONY += $(MAKECMDGOALS) __build_one_by_one
352
353$(MAKECMDGOALS): __build_one_by_one
354	@:
355
356__build_one_by_one:
357	$(Q)set -e; \
358	for i in $(MAKECMDGOALS); do \
359		$(MAKE) -f $(srctree)/Makefile $$i; \
360	done
361
362else # !mixed-build
363
364include $(srctree)/scripts/Kbuild.include
365
366# Read KERNELRELEASE from include/config/kernel.release (if it exists)
367KERNELRELEASE = $(call read-file, include/config/kernel.release)
368KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
369export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
370
371include $(srctree)/scripts/subarch.include
372
373# Cross compiling and selecting different set of gcc/bin-utils
374# ---------------------------------------------------------------------------
375#
376# When performing cross compilation for other architectures ARCH shall be set
377# to the target architecture. (See arch/* for the possibilities).
378# ARCH can be set during invocation of make:
379# make ARCH=ia64
380# Another way is to have ARCH set in the environment.
381# The default ARCH is the host where make is executed.
382
383# CROSS_COMPILE specify the prefix used for all executables used
384# during compilation. Only gcc and related bin-utils executables
385# are prefixed with $(CROSS_COMPILE).
386# CROSS_COMPILE can be set on the command line
387# make CROSS_COMPILE=ia64-linux-
388# Alternatively CROSS_COMPILE can be set in the environment.
389# Default value for CROSS_COMPILE is not to prefix executables
390# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
391ARCH		?= $(SUBARCH)
392
393# Architecture as present in compile.h
394UTS_MACHINE 	:= $(ARCH)
395SRCARCH 	:= $(ARCH)
396
397# Additional ARCH settings for x86
398ifeq ($(ARCH),i386)
399        SRCARCH := x86
400endif
401ifeq ($(ARCH),x86_64)
402        SRCARCH := x86
403endif
404
405# Additional ARCH settings for sparc
406ifeq ($(ARCH),sparc32)
407       SRCARCH := sparc
408endif
409ifeq ($(ARCH),sparc64)
410       SRCARCH := sparc
411endif
412
413# Additional ARCH settings for parisc
414ifeq ($(ARCH),parisc64)
415       SRCARCH := parisc
416endif
417
418export cross_compiling :=
419ifneq ($(SRCARCH),$(SUBARCH))
420cross_compiling := 1
421endif
422
423KCONFIG_CONFIG	?= .config
424export KCONFIG_CONFIG
425
426# SHELL used by kbuild
427CONFIG_SHELL := sh
428
429HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
430HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
431HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
432
433ifneq ($(LLVM),)
434ifneq ($(filter %/,$(LLVM)),)
435LLVM_PREFIX := $(LLVM)
436else ifneq ($(filter -%,$(LLVM)),)
437LLVM_SUFFIX := $(LLVM)
438endif
439
440HOSTCC	= $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
441HOSTCXX	= $(LLVM_PREFIX)clang++$(LLVM_SUFFIX)
442else
443HOSTCC	= gcc
444HOSTCXX	= g++
445endif
446HOSTRUSTC = rustc
447HOSTPKG_CONFIG	= pkg-config
448
449KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
450			 -O2 -fomit-frame-pointer -std=gnu11 \
451			 -Wdeclaration-after-statement
452KBUILD_USERCFLAGS  := $(KBUILD_USERHOSTCFLAGS) $(USERCFLAGS)
453KBUILD_USERLDFLAGS := $(USERLDFLAGS)
454
455# These flags apply to all Rust code in the tree, including the kernel and
456# host programs.
457export rust_common_flags := --edition=2021 \
458			    -Zbinary_dep_depinfo=y \
459			    -Dunsafe_op_in_unsafe_fn -Drust_2018_idioms \
460			    -Dunreachable_pub -Dnon_ascii_idents \
461			    -Wmissing_docs \
462			    -Drustdoc::missing_crate_level_docs \
463			    -Dclippy::correctness -Dclippy::style \
464			    -Dclippy::suspicious -Dclippy::complexity \
465			    -Dclippy::perf \
466			    -Dclippy::let_unit_value -Dclippy::mut_mut \
467			    -Dclippy::needless_bitwise_bool \
468			    -Dclippy::needless_continue \
469			    -Wclippy::dbg_macro
470
471KBUILD_HOSTCFLAGS   := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
472KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
473KBUILD_HOSTRUSTFLAGS := $(rust_common_flags) -O -Cstrip=debuginfo \
474			-Zallow-features= $(HOSTRUSTFLAGS)
475KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
476KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
477
478# Make variables (CC, etc...)
479CPP		= $(CC) -E
480ifneq ($(LLVM),)
481CC		= $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
482LD		= $(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX)
483AR		= $(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX)
484NM		= $(LLVM_PREFIX)llvm-nm$(LLVM_SUFFIX)
485OBJCOPY		= $(LLVM_PREFIX)llvm-objcopy$(LLVM_SUFFIX)
486OBJDUMP		= $(LLVM_PREFIX)llvm-objdump$(LLVM_SUFFIX)
487READELF		= $(LLVM_PREFIX)llvm-readelf$(LLVM_SUFFIX)
488STRIP		= $(LLVM_PREFIX)llvm-strip$(LLVM_SUFFIX)
489else
490CC		= $(CROSS_COMPILE)gcc
491LD		= $(CROSS_COMPILE)ld
492AR		= $(CROSS_COMPILE)ar
493NM		= $(CROSS_COMPILE)nm
494OBJCOPY		= $(CROSS_COMPILE)objcopy
495OBJDUMP		= $(CROSS_COMPILE)objdump
496READELF		= $(CROSS_COMPILE)readelf
497STRIP		= $(CROSS_COMPILE)strip
498endif
499RUSTC		= rustc
500RUSTDOC		= rustdoc
501RUSTFMT		= rustfmt
502CLIPPY_DRIVER	= clippy-driver
503BINDGEN		= bindgen
504CARGO		= cargo
505PAHOLE		= pahole
506RESOLVE_BTFIDS	= $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
507LEX		= flex
508YACC		= bison
509AWK		= awk
510INSTALLKERNEL  := installkernel
511DEPMOD		= depmod
512PERL		= perl
513PYTHON3		= python3
514CHECK		= sparse
515BASH		= bash
516KGZIP		= gzip
517KBZIP2		= bzip2
518KLZOP		= lzop
519LZMA		= lzma
520LZ4		= lz4c
521XZ		= xz
522ZSTD		= zstd
523
524PAHOLE_FLAGS	= $(shell PAHOLE=$(PAHOLE) $(srctree)/scripts/pahole-flags.sh)
525
526CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
527		  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
528NOSTDINC_FLAGS :=
529CFLAGS_MODULE   =
530RUSTFLAGS_MODULE =
531AFLAGS_MODULE   =
532LDFLAGS_MODULE  =
533CFLAGS_KERNEL	=
534RUSTFLAGS_KERNEL =
535AFLAGS_KERNEL	=
536LDFLAGS_vmlinux =
537
538# Use USERINCLUDE when you must reference the UAPI directories only.
539USERINCLUDE    := \
540		-I$(srctree)/arch/$(SRCARCH)/include/uapi \
541		-I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
542		-I$(srctree)/include/uapi \
543		-I$(objtree)/include/generated/uapi \
544                -include $(srctree)/include/linux/compiler-version.h \
545                -include $(srctree)/include/linux/kconfig.h
546
547# Use LINUXINCLUDE when you must reference the include/ directory.
548# Needed to be compatible with the O= option
549LINUXINCLUDE    := \
550		-I$(srctree)/arch/$(SRCARCH)/include \
551		-I$(objtree)/arch/$(SRCARCH)/include/generated \
552		$(if $(building_out_of_srctree),-I$(srctree)/include) \
553		-I$(objtree)/include \
554		$(USERINCLUDE)
555
556KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
557KBUILD_CFLAGS   := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
558		   -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
559		   -Werror=implicit-function-declaration -Werror=implicit-int \
560		   -Werror=return-type -Wno-format-security -funsigned-char \
561		   -std=gnu11
562KBUILD_CPPFLAGS := -D__KERNEL__
563KBUILD_RUSTFLAGS := $(rust_common_flags) \
564		    --target=$(objtree)/scripts/target.json \
565		    -Cpanic=abort -Cembed-bitcode=n -Clto=n \
566		    -Cforce-unwind-tables=n -Ccodegen-units=1 \
567		    -Csymbol-mangling-version=v0 \
568		    -Crelocation-model=static \
569		    -Zfunction-sections=n \
570		    -Dclippy::float_arithmetic
571
572KBUILD_AFLAGS_KERNEL :=
573KBUILD_CFLAGS_KERNEL :=
574KBUILD_RUSTFLAGS_KERNEL :=
575KBUILD_AFLAGS_MODULE  := -DMODULE
576KBUILD_CFLAGS_MODULE  := -DMODULE
577KBUILD_RUSTFLAGS_MODULE := --cfg MODULE
578KBUILD_LDFLAGS_MODULE :=
579KBUILD_LDFLAGS :=
580CLANG_FLAGS :=
581
582ifeq ($(KBUILD_CLIPPY),1)
583	RUSTC_OR_CLIPPY_QUIET := CLIPPY
584	RUSTC_OR_CLIPPY = $(CLIPPY_DRIVER)
585else
586	RUSTC_OR_CLIPPY_QUIET := RUSTC
587	RUSTC_OR_CLIPPY = $(RUSTC)
588endif
589
590ifdef RUST_LIB_SRC
591	export RUST_LIB_SRC
592endif
593
594# Allows the usage of unstable features in stable compilers.
595export RUSTC_BOOTSTRAP := 1
596
597export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG
598export RUSTC RUSTDOC RUSTFMT RUSTC_OR_CLIPPY_QUIET RUSTC_OR_CLIPPY BINDGEN CARGO
599export HOSTRUSTC KBUILD_HOSTRUSTFLAGS
600export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
601export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
602export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
603export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
604export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS
605
606export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
607export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
608export KBUILD_RUSTFLAGS RUSTFLAGS_KERNEL RUSTFLAGS_MODULE
609export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
610export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_RUSTFLAGS_MODULE KBUILD_LDFLAGS_MODULE
611export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL KBUILD_RUSTFLAGS_KERNEL
612export PAHOLE_FLAGS
613
614# Files to ignore in find ... statements
615
616export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
617			  -name CVS -o -name .pc -o -name .hg -o -name .git \) \
618			  -prune -o
619export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
620			 --exclude CVS --exclude .pc --exclude .hg --exclude .git
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
813KBUILD_CFLAGS	+= $(call cc-disable-warning,frame-address,)
814KBUILD_CFLAGS	+= $(call cc-disable-warning, format-truncation)
815KBUILD_CFLAGS	+= $(call cc-disable-warning, format-overflow)
816KBUILD_CFLAGS	+= $(call cc-disable-warning, address-of-packed-member)
817
818ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
819KBUILD_CFLAGS += -O2
820KBUILD_RUSTFLAGS += -Copt-level=2
821else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
822KBUILD_CFLAGS += -Os
823KBUILD_RUSTFLAGS += -Copt-level=s
824endif
825
826# Always set `debug-assertions` and `overflow-checks` because their default
827# depends on `opt-level` and `debug-assertions`, respectively.
828KBUILD_RUSTFLAGS += -Cdebug-assertions=$(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	+= $(call cc-option,-fno-allow-store-data-races)
837endif
838
839ifdef CONFIG_READABLE_ASM
840# Disable optimizations that make assembler listings hard to read.
841# reorder blocks reorders the control in the function
842# ipa clone creates specialized cloned functions
843# partial inlining inlines only parts of functions
844KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
845endif
846
847ifneq ($(CONFIG_FRAME_WARN),0)
848KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
849endif
850
851stackp-flags-y                                    := -fno-stack-protector
852stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
853stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
854
855KBUILD_CFLAGS += $(stackp-flags-y)
856
857KBUILD_CPPFLAGS-$(CONFIG_WERROR) += -Werror
858KBUILD_CPPFLAGS += $(KBUILD_CPPFLAGS-y)
859KBUILD_CFLAGS-$(CONFIG_CC_NO_ARRAY_BOUNDS) += -Wno-array-bounds
860
861KBUILD_RUSTFLAGS-$(CONFIG_WERROR) += -Dwarnings
862KBUILD_RUSTFLAGS += $(KBUILD_RUSTFLAGS-y)
863
864ifdef CONFIG_CC_IS_CLANG
865# The kernel builds with '-std=gnu11' so use of GNU extensions is acceptable.
866KBUILD_CFLAGS += -Wno-gnu
867else
868
869# gcc inanely warns about local variables called 'main'
870KBUILD_CFLAGS += -Wno-main
871endif
872
873# These warnings generated too much noise in a regular build.
874# Use make W=1 to enable them (see scripts/Makefile.extrawarn)
875KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
876KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
877
878# These result in bogus false positives
879KBUILD_CFLAGS += $(call cc-disable-warning, dangling-pointer)
880
881ifdef CONFIG_FRAME_POINTER
882KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
883KBUILD_RUSTFLAGS += -Cforce-frame-pointers=y
884else
885# Some targets (ARM with Thumb2, for example), can't be built with frame
886# pointers.  For those, we don't have FUNCTION_TRACER automatically
887# select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
888# incompatible with -fomit-frame-pointer with current GCC, so we don't use
889# -fomit-frame-pointer with FUNCTION_TRACER.
890# In the Rust target specification, "frame-pointer" is set explicitly
891# to "may-omit".
892ifndef CONFIG_FUNCTION_TRACER
893KBUILD_CFLAGS	+= -fomit-frame-pointer
894endif
895endif
896
897# Initialize all stack variables with a 0xAA pattern.
898ifdef CONFIG_INIT_STACK_ALL_PATTERN
899KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
900endif
901
902# Initialize all stack variables with a zero value.
903ifdef CONFIG_INIT_STACK_ALL_ZERO
904KBUILD_CFLAGS	+= -ftrivial-auto-var-init=zero
905ifdef CONFIG_CC_HAS_AUTO_VAR_INIT_ZERO_ENABLER
906# https://github.com/llvm/llvm-project/issues/44842
907CC_AUTO_VAR_INIT_ZERO_ENABLER := -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
908export CC_AUTO_VAR_INIT_ZERO_ENABLER
909KBUILD_CFLAGS	+= $(CC_AUTO_VAR_INIT_ZERO_ENABLER)
910endif
911endif
912
913# While VLAs have been removed, GCC produces unreachable stack probes
914# for the randomize_kstack_offset feature. Disable it for all compilers.
915KBUILD_CFLAGS	+= $(call cc-option, -fno-stack-clash-protection)
916
917# Clear used registers at func exit (to reduce data lifetime and ROP gadgets).
918ifdef CONFIG_ZERO_CALL_USED_REGS
919KBUILD_CFLAGS	+= -fzero-call-used-regs=used-gpr
920endif
921
922ifdef CONFIG_FUNCTION_TRACER
923ifdef CONFIG_FTRACE_MCOUNT_USE_CC
924  CC_FLAGS_FTRACE	+= -mrecord-mcount
925  ifdef CONFIG_HAVE_NOP_MCOUNT
926    ifeq ($(call cc-option-yn, -mnop-mcount),y)
927      CC_FLAGS_FTRACE	+= -mnop-mcount
928      CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
929    endif
930  endif
931endif
932ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
933  ifdef CONFIG_HAVE_OBJTOOL_NOP_MCOUNT
934    CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
935  endif
936endif
937ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
938  ifdef CONFIG_HAVE_C_RECORDMCOUNT
939    BUILD_C_RECORDMCOUNT := y
940    export BUILD_C_RECORDMCOUNT
941  endif
942endif
943ifdef CONFIG_HAVE_FENTRY
944  # s390-linux-gnu-gcc did not support -mfentry until gcc-9.
945  ifeq ($(call cc-option-yn, -mfentry),y)
946    CC_FLAGS_FTRACE	+= -mfentry
947    CC_FLAGS_USING	+= -DCC_USING_FENTRY
948  endif
949endif
950export CC_FLAGS_FTRACE
951KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
952KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
953endif
954
955# We trigger additional mismatches with less inlining
956ifdef CONFIG_DEBUG_SECTION_MISMATCH
957KBUILD_CFLAGS += -fno-inline-functions-called-once
958endif
959
960# `rustc`'s `-Zfunction-sections` applies to data too (as of 1.59.0).
961ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
962KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
963KBUILD_RUSTFLAGS_KERNEL += -Zfunction-sections=y
964LDFLAGS_vmlinux += --gc-sections
965endif
966
967ifdef CONFIG_SHADOW_CALL_STACK
968ifndef CONFIG_DYNAMIC_SCS
969CC_FLAGS_SCS	:= -fsanitize=shadow-call-stack
970KBUILD_CFLAGS	+= $(CC_FLAGS_SCS)
971endif
972export CC_FLAGS_SCS
973endif
974
975ifdef CONFIG_LTO_CLANG
976ifdef CONFIG_LTO_CLANG_THIN
977CC_FLAGS_LTO	:= -flto=thin -fsplit-lto-unit
978KBUILD_LDFLAGS	+= --thinlto-cache-dir=$(extmod_prefix).thinlto-cache
979else
980CC_FLAGS_LTO	:= -flto
981endif
982CC_FLAGS_LTO	+= -fvisibility=hidden
983
984# Limit inlining across translation units to reduce binary size
985KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
986
987# Check for frame size exceeding threshold during prolog/epilog insertion
988# when using lld < 13.0.0.
989ifneq ($(CONFIG_FRAME_WARN),0)
990ifeq ($(call test-lt, $(CONFIG_LLD_VERSION), 130000),y)
991KBUILD_LDFLAGS	+= -plugin-opt=-warn-stack-size=$(CONFIG_FRAME_WARN)
992endif
993endif
994endif
995
996ifdef CONFIG_LTO
997KBUILD_CFLAGS	+= -fno-lto $(CC_FLAGS_LTO)
998KBUILD_AFLAGS	+= -fno-lto
999export CC_FLAGS_LTO
1000endif
1001
1002ifdef CONFIG_CFI_CLANG
1003CC_FLAGS_CFI	:= -fsanitize=kcfi
1004KBUILD_CFLAGS	+= $(CC_FLAGS_CFI)
1005export CC_FLAGS_CFI
1006endif
1007
1008ifneq ($(CONFIG_FUNCTION_ALIGNMENT),0)
1009KBUILD_CFLAGS += -falign-functions=$(CONFIG_FUNCTION_ALIGNMENT)
1010endif
1011
1012# arch Makefile may override CC so keep this after arch Makefile is included
1013NOSTDINC_FLAGS += -nostdinc
1014
1015# warn about C99 declaration after statement
1016KBUILD_CFLAGS += -Wdeclaration-after-statement
1017
1018# Variable Length Arrays (VLAs) should not be used anywhere in the kernel
1019KBUILD_CFLAGS += -Wvla
1020
1021# disable pointer signed / unsigned warnings in gcc 4.0
1022KBUILD_CFLAGS += -Wno-pointer-sign
1023
1024# In order to make sure new function cast mismatches are not introduced
1025# in the kernel (to avoid tripping CFI checking), the kernel should be
1026# globally built with -Wcast-function-type.
1027KBUILD_CFLAGS += $(call cc-option, -Wcast-function-type)
1028
1029# disable stringop warnings in gcc 8+
1030KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
1031
1032# We'll want to enable this eventually, but it's not going away for 5.7 at least
1033KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
1034
1035# Another good warning that we'll want to enable eventually
1036KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
1037
1038# Enabled with W=2, disabled by default as noisy
1039ifdef CONFIG_CC_IS_GCC
1040KBUILD_CFLAGS += -Wno-maybe-uninitialized
1041endif
1042
1043# The allocators already balk at large sizes, so silence the compiler
1044# warnings for bounds checks involving those possible values. While
1045# -Wno-alloc-size-larger-than would normally be used here, earlier versions
1046# of gcc (<9.1) weirdly don't handle the option correctly when _other_
1047# warnings are produced (?!). Using -Walloc-size-larger-than=SIZE_MAX
1048# doesn't work (as it is documented to), silently resolving to "0" prior to
1049# version 9.1 (and producing an error more recently). Numeric values larger
1050# than PTRDIFF_MAX also don't work prior to version 9.1, which are silently
1051# ignored, continuing to default to PTRDIFF_MAX. So, left with no other
1052# choice, we must perform a versioned check to disable this warning.
1053# https://lore.kernel.org/lkml/20210824115859.187f272f@canb.auug.org.au
1054KBUILD_CFLAGS-$(call gcc-min-version, 90100) += -Wno-alloc-size-larger-than
1055KBUILD_CFLAGS += $(KBUILD_CFLAGS-y) $(CONFIG_CC_IMPLICIT_FALLTHROUGH)
1056
1057# disable invalid "can't wrap" optimizations for signed / pointers
1058KBUILD_CFLAGS	+= -fno-strict-overflow
1059
1060# Make sure -fstack-check isn't enabled (like gentoo apparently did)
1061KBUILD_CFLAGS  += -fno-stack-check
1062
1063# conserve stack if available
1064ifdef CONFIG_CC_IS_GCC
1065KBUILD_CFLAGS   += -fconserve-stack
1066endif
1067
1068# Prohibit date/time macros, which would make the build non-deterministic
1069KBUILD_CFLAGS   += -Werror=date-time
1070
1071# enforce correct pointer usage
1072KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)
1073
1074# Require designated initializers for all marked structures
1075KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)
1076
1077# change __FILE__ to the relative path from the srctree
1078KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
1079
1080# include additional Makefiles when needed
1081include-y			:= scripts/Makefile.extrawarn
1082include-$(CONFIG_DEBUG_INFO)	+= scripts/Makefile.debug
1083include-$(CONFIG_KASAN)		+= scripts/Makefile.kasan
1084include-$(CONFIG_KCSAN)		+= scripts/Makefile.kcsan
1085include-$(CONFIG_KMSAN)		+= scripts/Makefile.kmsan
1086include-$(CONFIG_UBSAN)		+= scripts/Makefile.ubsan
1087include-$(CONFIG_KCOV)		+= scripts/Makefile.kcov
1088include-$(CONFIG_RANDSTRUCT)	+= scripts/Makefile.randstruct
1089include-$(CONFIG_GCC_PLUGINS)	+= scripts/Makefile.gcc-plugins
1090
1091include $(addprefix $(srctree)/, $(include-y))
1092
1093# scripts/Makefile.gcc-plugins is intentionally included last.
1094# Do not add $(call cc-option,...) below this line. When you build the kernel
1095# from the clean source tree, the GCC plugins do not exist at this point.
1096
1097# Add user supplied CPPFLAGS, AFLAGS, CFLAGS and RUSTFLAGS as the last assignments
1098KBUILD_CPPFLAGS += $(KCPPFLAGS)
1099KBUILD_AFLAGS   += $(KAFLAGS)
1100KBUILD_CFLAGS   += $(KCFLAGS)
1101KBUILD_RUSTFLAGS += $(KRUSTFLAGS)
1102
1103KBUILD_LDFLAGS_MODULE += --build-id=sha1
1104LDFLAGS_vmlinux += --build-id=sha1
1105
1106KBUILD_LDFLAGS	+= -z noexecstack
1107ifeq ($(CONFIG_LD_IS_BFD),y)
1108KBUILD_LDFLAGS	+= $(call ld-option,--no-warn-rwx-segments)
1109endif
1110
1111ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1112LDFLAGS_vmlinux	+= -X
1113endif
1114
1115ifeq ($(CONFIG_RELR),y)
1116LDFLAGS_vmlinux	+= --pack-dyn-relocs=relr --use-android-relr-tags
1117endif
1118
1119# We never want expected sections to be placed heuristically by the
1120# linker. All sections should be explicitly named in the linker script.
1121ifdef CONFIG_LD_ORPHAN_WARN
1122LDFLAGS_vmlinux += --orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL)
1123endif
1124
1125# Align the bit size of userspace programs with the kernel
1126KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1127KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1128
1129# make the checker run with the right architecture
1130CHECKFLAGS += --arch=$(ARCH)
1131
1132# insure the checker run with the right endianness
1133CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1134
1135# the checker needs the correct machine size
1136CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1137
1138# Default kernel image to build when no specific target is given.
1139# KBUILD_IMAGE may be overruled on the command line or
1140# set in the environment
1141# Also any assignments in arch/$(ARCH)/Makefile take precedence over
1142# this default value
1143export KBUILD_IMAGE ?= vmlinux
1144
1145#
1146# INSTALL_PATH specifies where to place the updated kernel and system map
1147# images. Default is /boot, but you can set it to other values
1148export	INSTALL_PATH ?= /boot
1149
1150#
1151# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1152# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1153# an argument if needed. Otherwise it defaults to the kernel install path
1154#
1155export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1156
1157#
1158# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1159# relocations required by build roots.  This is not defined in the
1160# makefile but the argument can be passed to make if needed.
1161#
1162
1163MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1164export MODLIB
1165
1166PHONY += prepare0
1167
1168export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
1169export MODORDER := $(extmod_prefix)modules.order
1170export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
1171
1172ifeq ($(KBUILD_EXTMOD),)
1173
1174build-dir	:= .
1175clean-dirs	:= $(sort . Documentation \
1176		     $(patsubst %/,%,$(filter %/, $(core-) \
1177			$(drivers-) $(libs-))))
1178
1179export ARCH_CORE	:= $(core-y)
1180export ARCH_LIB		:= $(filter %/, $(libs-y))
1181export ARCH_DRIVERS	:= $(drivers-y) $(drivers-m)
1182# Externally visible symbols (used by link-vmlinux.sh)
1183
1184KBUILD_VMLINUX_OBJS := ./built-in.a
1185ifdef CONFIG_MODULES
1186KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1187KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1188else
1189KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1190endif
1191
1192export KBUILD_VMLINUX_LIBS
1193export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1194
1195# Recurse until adjust_autoksyms.sh is satisfied
1196PHONY += autoksyms_recursive
1197ifdef CONFIG_TRIM_UNUSED_KSYMS
1198# For the kernel to actually contain only the needed exported symbols,
1199# we have to build modules as well to determine what those symbols are.
1200# (this can be evaluated only once include/config/auto.conf has been included)
1201KBUILD_MODULES := 1
1202
1203autoksyms_recursive: $(build-dir) modules.order
1204	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1205	  "$(MAKE) -f $(srctree)/Makefile autoksyms_recursive"
1206endif
1207
1208autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1209
1210quiet_cmd_autoksyms_h = GEN     $@
1211      cmd_autoksyms_h = mkdir -p $(dir $@); \
1212			$(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@
1213
1214$(autoksyms_h):
1215	$(call cmd,autoksyms_h)
1216
1217# '$(AR) mPi' needs 'T' to workaround the bug of llvm-ar <= 14
1218quiet_cmd_ar_vmlinux.a = AR      $@
1219      cmd_ar_vmlinux.a = \
1220	rm -f $@; \
1221	$(AR) cDPrST $@ $(KBUILD_VMLINUX_OBJS); \
1222	$(AR) mPiT $$($(AR) t $@ | sed -n 1p) $@ $$($(AR) t $@ | grep -F -f $(srctree)/scripts/head-object-list.txt)
1223
1224targets += vmlinux.a
1225vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt autoksyms_recursive FORCE
1226	$(call if_changed,ar_vmlinux.a)
1227
1228PHONY += vmlinux_o
1229vmlinux_o: vmlinux.a $(KBUILD_VMLINUX_LIBS)
1230	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o
1231
1232vmlinux.o modules.builtin.modinfo modules.builtin: vmlinux_o
1233	@:
1234
1235PHONY += vmlinux
1236# LDFLAGS_vmlinux in the top Makefile defines linker flags for the top vmlinux,
1237# not for decompressors. LDFLAGS_vmlinux in arch/*/boot/compressed/Makefile is
1238# unrelated; the decompressors just happen to have the same base name,
1239# arch/*/boot/compressed/vmlinux.
1240# Export LDFLAGS_vmlinux only to scripts/Makefile.vmlinux.
1241#
1242# _LDFLAGS_vmlinux is a workaround for the 'private export' bug:
1243#   https://savannah.gnu.org/bugs/?61463
1244# For Make > 4.4, the following simple code will work:
1245#  vmlinux: private export LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1246vmlinux: private _LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1247vmlinux: export LDFLAGS_vmlinux = $(_LDFLAGS_vmlinux)
1248vmlinux: vmlinux.o $(KBUILD_LDS) modpost
1249	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux
1250
1251# The actual objects are generated when descending,
1252# make sure no implicit rule kicks in
1253$(sort $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)): . ;
1254
1255ifeq ($(origin KERNELRELEASE),file)
1256filechk_kernel.release = $(srctree)/scripts/setlocalversion $(srctree)
1257else
1258filechk_kernel.release = echo $(KERNELRELEASE)
1259endif
1260
1261# Store (new) KERNELRELEASE string in include/config/kernel.release
1262include/config/kernel.release: FORCE
1263	$(call filechk,kernel.release)
1264
1265# Additional helpers built in scripts/
1266# Carefully list dependencies so we do not try to build scripts twice
1267# in parallel
1268PHONY += scripts
1269scripts: scripts_basic scripts_dtc
1270	$(Q)$(MAKE) $(build)=$(@)
1271
1272# Things we need to do before we recursively start building the kernel
1273# or the modules are listed in "prepare".
1274# A multi level approach is used. prepareN is processed before prepareN-1.
1275# archprepare is used in arch Makefiles and when processed asm symlink,
1276# version.h and scripts_basic is processed / created.
1277
1278PHONY += prepare archprepare
1279
1280archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1281	asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h \
1282	include/generated/compile.h include/generated/autoconf.h remove-stale-files
1283
1284prepare0: archprepare
1285	$(Q)$(MAKE) $(build)=scripts/mod
1286	$(Q)$(MAKE) $(build)=. prepare
1287
1288# All the preparing..
1289prepare: prepare0
1290ifdef CONFIG_RUST
1291	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh -v
1292	$(Q)$(MAKE) $(build)=rust
1293endif
1294
1295PHONY += remove-stale-files
1296remove-stale-files:
1297	$(Q)$(srctree)/scripts/remove-stale-files
1298
1299# Support for using generic headers in asm-generic
1300asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1301
1302PHONY += asm-generic uapi-asm-generic
1303asm-generic: uapi-asm-generic
1304	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1305	generic=include/asm-generic
1306uapi-asm-generic:
1307	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1308	generic=include/uapi/asm-generic
1309
1310# Generate some files
1311# ---------------------------------------------------------------------------
1312
1313# KERNELRELEASE can change from a few different places, meaning version.h
1314# needs to be updated, so this check is forced on all builds
1315
1316uts_len := 64
1317define filechk_utsrelease.h
1318	if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1319	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1320	  exit 1;                                                         \
1321	fi;                                                               \
1322	echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1323endef
1324
1325define filechk_version.h
1326	if [ $(SUBLEVEL) -gt 255 ]; then                                 \
1327		echo \#define LINUX_VERSION_CODE $(shell                 \
1328		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1329	else                                                             \
1330		echo \#define LINUX_VERSION_CODE $(shell                 \
1331		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1332	fi;                                                              \
1333	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
1334	((c) > 255 ? 255 : (c)))';                                       \
1335	echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
1336	echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
1337	echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1338endef
1339
1340$(version_h): PATCHLEVEL := $(or $(PATCHLEVEL), 0)
1341$(version_h): SUBLEVEL := $(or $(SUBLEVEL), 0)
1342$(version_h): FORCE
1343	$(call filechk,version.h)
1344
1345include/generated/utsrelease.h: include/config/kernel.release FORCE
1346	$(call filechk,utsrelease.h)
1347
1348filechk_compile.h = $(srctree)/scripts/mkcompile_h \
1349	"$(UTS_MACHINE)" "$(CONFIG_CC_VERSION_TEXT)" "$(LD)"
1350
1351include/generated/compile.h: FORCE
1352	$(call filechk,compile.h)
1353
1354PHONY += headerdep
1355headerdep:
1356	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1357	$(srctree)/scripts/headerdep.pl -I$(srctree)/include
1358
1359# ---------------------------------------------------------------------------
1360# Kernel headers
1361
1362#Default location for installed headers
1363export INSTALL_HDR_PATH = $(objtree)/usr
1364
1365quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1366      cmd_headers_install = \
1367	mkdir -p $(INSTALL_HDR_PATH); \
1368	rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1369	usr/include $(INSTALL_HDR_PATH)
1370
1371PHONY += headers_install
1372headers_install: headers
1373	$(call cmd,headers_install)
1374
1375PHONY += archheaders archscripts
1376
1377hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1378
1379PHONY += headers
1380headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1381	$(if $(filter um, $(SRCARCH)), $(error Headers not exportable for UML))
1382	$(Q)$(MAKE) $(hdr-inst)=include/uapi
1383	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1384
1385ifdef CONFIG_HEADERS_INSTALL
1386prepare: headers
1387endif
1388
1389PHONY += scripts_unifdef
1390scripts_unifdef: scripts_basic
1391	$(Q)$(MAKE) $(build)=scripts scripts/unifdef
1392
1393# ---------------------------------------------------------------------------
1394# Install
1395
1396# Many distributions have the custom install script, /sbin/installkernel.
1397# If DKMS is installed, 'make install' will eventually recurse back
1398# to this Makefile to build and install external modules.
1399# Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
1400
1401quiet_cmd_install = INSTALL $(INSTALL_PATH)
1402      cmd_install = unset sub_make_done; $(srctree)/scripts/install.sh
1403
1404# ---------------------------------------------------------------------------
1405# Tools
1406
1407ifdef CONFIG_OBJTOOL
1408prepare: tools/objtool
1409endif
1410
1411ifdef CONFIG_BPF
1412ifdef CONFIG_DEBUG_INFO_BTF
1413prepare: tools/bpf/resolve_btfids
1414endif
1415endif
1416
1417PHONY += resolve_btfids_clean
1418
1419resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1420
1421# tools/bpf/resolve_btfids directory might not exist
1422# in output directory, skip its clean in that case
1423resolve_btfids_clean:
1424ifneq ($(wildcard $(resolve_btfids_O)),)
1425	$(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1426endif
1427
1428# Clear a bunch of variables before executing the submake
1429ifeq ($(quiet),silent_)
1430tools_silent=s
1431endif
1432
1433tools/: FORCE
1434	$(Q)mkdir -p $(objtree)/tools
1435	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1436
1437tools/%: FORCE
1438	$(Q)mkdir -p $(objtree)/tools
1439	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1440
1441# ---------------------------------------------------------------------------
1442# Kernel selftest
1443
1444PHONY += kselftest
1445kselftest: headers
1446	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1447
1448kselftest-%: headers FORCE
1449	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1450
1451PHONY += kselftest-merge
1452kselftest-merge:
1453	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1454	$(Q)find $(srctree)/tools/testing/selftests -name config | \
1455		xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1456	$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1457
1458# ---------------------------------------------------------------------------
1459# Devicetree files
1460
1461ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1462dtstree := arch/$(SRCARCH)/boot/dts
1463endif
1464
1465ifneq ($(dtstree),)
1466
1467%.dtb: dtbs_prepare
1468	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1469
1470%.dtbo: dtbs_prepare
1471	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1472
1473PHONY += dtbs dtbs_prepare dtbs_install dtbs_check
1474dtbs: dtbs_prepare
1475	$(Q)$(MAKE) $(build)=$(dtstree)
1476
1477# include/config/kernel.release is actually needed when installing DTBs because
1478# INSTALL_DTBS_PATH contains $(KERNELRELEASE). However, we do not want to make
1479# dtbs_install depend on it as dtbs_install may run as root.
1480dtbs_prepare: include/config/kernel.release scripts_dtc
1481
1482ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1483export CHECK_DTBS=y
1484endif
1485
1486ifneq ($(CHECK_DTBS),)
1487dtbs_prepare: dt_binding_check
1488endif
1489
1490dtbs_check: dtbs
1491
1492dtbs_install:
1493	$(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1494
1495ifdef CONFIG_OF_EARLY_FLATTREE
1496all: dtbs
1497endif
1498
1499endif
1500
1501PHONY += scripts_dtc
1502scripts_dtc: scripts_basic
1503	$(Q)$(MAKE) $(build)=scripts/dtc
1504
1505ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1506export CHECK_DT_BINDING=y
1507endif
1508
1509PHONY += dt_binding_check
1510dt_binding_check: scripts_dtc
1511	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1512
1513PHONY += dt_compatible_check
1514dt_compatible_check: dt_binding_check
1515	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1516
1517# ---------------------------------------------------------------------------
1518# Modules
1519
1520ifdef CONFIG_MODULES
1521
1522# By default, build modules as well
1523
1524all: modules
1525
1526# When we're building modules with modversions, we need to consider
1527# the built-in objects during the descend as well, in order to
1528# make sure the checksums are up to date before we record them.
1529ifdef CONFIG_MODVERSIONS
1530  KBUILD_BUILTIN := 1
1531endif
1532
1533# Build modules
1534#
1535
1536# *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFO_BTF_MODULES
1537# is an exception.
1538ifdef CONFIG_DEBUG_INFO_BTF_MODULES
1539KBUILD_BUILTIN := 1
1540modules: vmlinux
1541endif
1542
1543modules: modules_prepare
1544
1545# Target to prepare building external modules
1546modules_prepare: prepare
1547	$(Q)$(MAKE) $(build)=scripts scripts/module.lds
1548
1549export modules_sign_only :=
1550
1551ifeq ($(CONFIG_MODULE_SIG),y)
1552PHONY += modules_sign
1553modules_sign: modules_install
1554	@:
1555
1556# modules_sign is a subset of modules_install.
1557# 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1558ifeq ($(filter modules_install,$(MAKECMDGOALS)),)
1559modules_sign_only := y
1560endif
1561endif
1562
1563modinst_pre :=
1564ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
1565modinst_pre := __modinst_pre
1566endif
1567
1568modules_install: $(modinst_pre)
1569PHONY += __modinst_pre
1570__modinst_pre:
1571	@rm -rf $(MODLIB)/kernel
1572	@rm -f $(MODLIB)/source
1573	@mkdir -p $(MODLIB)/kernel
1574	@ln -s $(abspath $(srctree)) $(MODLIB)/source
1575	@if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
1576		rm -f $(MODLIB)/build ; \
1577		ln -s $(CURDIR) $(MODLIB)/build ; \
1578	fi
1579	@sed 's:^\(.*\)\.o$$:kernel/\1.ko:' modules.order > $(MODLIB)/modules.order
1580	@cp -f modules.builtin $(MODLIB)/
1581	@cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
1582
1583endif # CONFIG_MODULES
1584
1585###
1586# Cleaning is done on three levels.
1587# make clean     Delete most generated files
1588#                Leave enough to build external modules
1589# make mrproper  Delete the current configuration, and all generated files
1590# make distclean Remove editor backup files, patch leftover files and the like
1591
1592# Directories & files removed with 'make clean'
1593CLEAN_FILES += include/ksym vmlinux.symvers modules-only.symvers \
1594	       modules.builtin modules.builtin.modinfo modules.nsdeps \
1595	       compile_commands.json .thinlto-cache rust/test rust/doc \
1596	       rust-project.json .vmlinux.objs .vmlinux.export.c
1597
1598# Directories & files removed with 'make mrproper'
1599MRPROPER_FILES += include/config include/generated          \
1600		  arch/$(SRCARCH)/include/generated .objdiff \
1601		  debian snap tar-install \
1602		  .config .config.old .version \
1603		  Module.symvers \
1604		  certs/signing_key.pem \
1605		  certs/x509.genkey \
1606		  vmlinux-gdb.py \
1607		  *.spec rpmbuild \
1608		  rust/libmacros.so
1609
1610# clean - Delete most, but leave enough to build external modules
1611#
1612clean: rm-files := $(CLEAN_FILES)
1613
1614PHONY += archclean vmlinuxclean
1615
1616vmlinuxclean:
1617	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1618	$(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1619
1620clean: archclean vmlinuxclean resolve_btfids_clean
1621
1622# mrproper - Delete all generated files, including .config
1623#
1624mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1625mrproper-dirs      := $(addprefix _mrproper_,scripts)
1626
1627PHONY += $(mrproper-dirs) mrproper
1628$(mrproper-dirs):
1629	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1630
1631mrproper: clean $(mrproper-dirs)
1632	$(call cmd,rmfiles)
1633	@find . $(RCS_FIND_IGNORE) \
1634		\( -name '*.rmeta' \) \
1635		-type f -print | xargs rm -f
1636
1637# distclean
1638#
1639PHONY += distclean
1640
1641distclean: mrproper
1642	@find . $(RCS_FIND_IGNORE) \
1643		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1644		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
1645		-o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1646		-o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1647		-type f -print | xargs rm -f
1648
1649
1650# Packaging of the kernel to various formats
1651# ---------------------------------------------------------------------------
1652
1653%src-pkg: FORCE
1654	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1655%pkg: include/config/kernel.release FORCE
1656	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1657
1658# Brief documentation of the typical targets used
1659# ---------------------------------------------------------------------------
1660
1661boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1662boards := $(sort $(notdir $(boards)))
1663board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1664board-dirs := $(sort $(notdir $(board-dirs:/=)))
1665
1666PHONY += help
1667help:
1668	@echo  'Cleaning targets:'
1669	@echo  '  clean		  - Remove most generated files but keep the config and'
1670	@echo  '                    enough build support to build external modules'
1671	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
1672	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
1673	@echo  ''
1674	@echo  'Configuration targets:'
1675	@$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1676	@echo  ''
1677	@echo  'Other generic targets:'
1678	@echo  '  all		  - Build all targets marked with [*]'
1679	@echo  '* vmlinux	  - Build the bare kernel'
1680	@echo  '* modules	  - Build all modules'
1681	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1682	@echo  '  dir/            - Build all files in dir and below'
1683	@echo  '  dir/file.[ois]  - Build specified target only'
1684	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1685	@echo  '                    (requires compiler support for LLVM assembly generation)'
1686	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1687	@echo  '                    (requires a recent binutils and recent build (System.map))'
1688	@echo  '  dir/file.ko     - Build module including final link'
1689	@echo  '  modules_prepare - Set up for building external modules'
1690	@echo  '  tags/TAGS	  - Generate tags file for editors'
1691	@echo  '  cscope	  - Generate cscope index'
1692	@echo  '  gtags           - Generate GNU GLOBAL index'
1693	@echo  '  kernelrelease	  - Output the release version string (use with make -s)'
1694	@echo  '  kernelversion	  - Output the version stored in Makefile (use with make -s)'
1695	@echo  '  image_name	  - Output the image name (use with make -s)'
1696	@echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1697	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1698	 echo  ''
1699	@echo  'Static analysers:'
1700	@echo  '  checkstack      - Generate a list of stack hogs'
1701	@echo  '  versioncheck    - Sanity check on version.h usage'
1702	@echo  '  includecheck    - Check for duplicate included header files'
1703	@echo  '  export_report   - List the usages of all exported symbols'
1704	@echo  '  headerdep       - Detect inclusion cycles in headers'
1705	@echo  '  coccicheck      - Check with Coccinelle'
1706	@echo  '  clang-analyzer  - Check with clang static analyzer'
1707	@echo  '  clang-tidy      - Check with clang-tidy'
1708	@echo  ''
1709	@echo  'Tools:'
1710	@echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1711	@echo  ''
1712	@echo  'Kernel selftest:'
1713	@echo  '  kselftest         - Build and run kernel selftest'
1714	@echo  '                      Build, install, and boot kernel before'
1715	@echo  '                      running kselftest on it'
1716	@echo  '                      Run as root for full coverage'
1717	@echo  '  kselftest-all     - Build kernel selftest'
1718	@echo  '  kselftest-install - Build and install kernel selftest'
1719	@echo  '  kselftest-clean   - Remove all generated kselftest files'
1720	@echo  '  kselftest-merge   - Merge all the config dependencies of'
1721	@echo  '		      kselftest to existing .config.'
1722	@echo  ''
1723	@echo  'Rust targets:'
1724	@echo  '  rustavailable   - Checks whether the Rust toolchain is'
1725	@echo  '		    available and, if not, explains why.'
1726	@echo  '  rustfmt	  - Reformat all the Rust code in the kernel'
1727	@echo  '  rustfmtcheck	  - Checks if all the Rust code in the kernel'
1728	@echo  '		    is formatted, printing a diff otherwise.'
1729	@echo  '  rustdoc	  - Generate Rust documentation'
1730	@echo  '		    (requires kernel .config)'
1731	@echo  '  rusttest        - Runs the Rust tests'
1732	@echo  '                    (requires kernel .config; downloads external repos)'
1733	@echo  '  rust-analyzer	  - Generate rust-project.json rust-analyzer support file'
1734	@echo  '		    (requires kernel .config)'
1735	@echo  '  dir/file.[os]   - Build specified target only'
1736	@echo  '  dir/file.rsi    - Build macro expanded source, similar to C preprocessing.'
1737	@echo  '                    Run with RUSTFMT=n to skip reformatting if needed.'
1738	@echo  '                    The output is not intended to be compilable.'
1739	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1740	@echo  ''
1741	@$(if $(dtstree), \
1742		echo 'Devicetree:'; \
1743		echo '* dtbs             - Build device tree blobs for enabled boards'; \
1744		echo '  dtbs_install     - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1745		echo '  dt_binding_check - Validate device tree binding documents'; \
1746		echo '  dtbs_check       - Validate device tree source files';\
1747		echo '')
1748
1749	@echo 'Userspace tools targets:'
1750	@echo '  use "make tools/help"'
1751	@echo '  or  "cd tools; make help"'
1752	@echo  ''
1753	@echo  'Kernel packaging:'
1754	@$(MAKE) -f $(srctree)/scripts/Makefile.package help
1755	@echo  ''
1756	@echo  'Documentation targets:'
1757	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1758	@echo  ''
1759	@echo  'Architecture specific targets ($(SRCARCH)):'
1760	@$(or $(archhelp),\
1761		echo '  No architecture specific help defined for $(SRCARCH)')
1762	@echo  ''
1763	@$(if $(boards), \
1764		$(foreach b, $(boards), \
1765		printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1766		echo '')
1767	@$(if $(board-dirs), \
1768		$(foreach b, $(board-dirs), \
1769		printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1770		printf "  %-16s - Show all of the above\\n" help-boards; \
1771		echo '')
1772
1773	@echo  '  make V=n   [targets] 1: verbose build'
1774	@echo  '                       2: give reason for rebuild of target'
1775	@echo  '                       V=1 and V=2 can be combined with V=12'
1776	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1777	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1778	@echo  '                       (sparse by default)'
1779	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1780	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1781	@echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
1782	@echo  '		1: warnings which may be relevant and do not occur too often'
1783	@echo  '		2: warnings which occur quite often but may still be relevant'
1784	@echo  '		3: more obscure warnings, can most likely be ignored'
1785	@echo  '		e: warnings are being treated as errors'
1786	@echo  '		Multiple levels can be combined with W=12 or W=123'
1787	@$(if $(dtstree), \
1788		echo '  make CHECK_DTBS=1 [targets] Check all generated dtb files against schema'; \
1789		echo '         This can be applied both to "dtbs" and to individual "foo.dtb" targets' ; \
1790		)
1791	@echo  ''
1792	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
1793	@echo  'For further info see the ./README file'
1794
1795
1796help-board-dirs := $(addprefix help-,$(board-dirs))
1797
1798help-boards: $(help-board-dirs)
1799
1800boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1801
1802$(help-board-dirs): help-%:
1803	@echo  'Architecture specific targets ($(SRCARCH) $*):'
1804	@$(if $(boards-per-dir), \
1805		$(foreach b, $(boards-per-dir), \
1806		printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1807		echo '')
1808
1809
1810# Documentation targets
1811# ---------------------------------------------------------------------------
1812DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1813	       linkcheckdocs dochelp refcheckdocs texinfodocs infodocs
1814PHONY += $(DOC_TARGETS)
1815$(DOC_TARGETS):
1816	$(Q)$(MAKE) $(build)=Documentation $@
1817
1818
1819# Rust targets
1820# ---------------------------------------------------------------------------
1821
1822# "Is Rust available?" target
1823PHONY += rustavailable
1824rustavailable:
1825	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh -v && echo "Rust is available!"
1826
1827# Documentation target
1828#
1829# Using the singular to avoid running afoul of `no-dot-config-targets`.
1830PHONY += rustdoc
1831rustdoc: prepare
1832	$(Q)$(MAKE) $(build)=rust $@
1833
1834# Testing target
1835PHONY += rusttest
1836rusttest: prepare
1837	$(Q)$(MAKE) $(build)=rust $@
1838
1839# Formatting targets
1840PHONY += rustfmt rustfmtcheck
1841
1842# We skip `rust/alloc` since we want to minimize the diff w.r.t. upstream.
1843#
1844# We match using absolute paths since `find` does not resolve them
1845# when matching, which is a problem when e.g. `srctree` is `..`.
1846# We `grep` afterwards in order to remove the directory entry itself.
1847rustfmt:
1848	$(Q)find $(abs_srctree) -type f -name '*.rs' \
1849		-o -path $(abs_srctree)/rust/alloc -prune \
1850		-o -path $(abs_objtree)/rust/test -prune \
1851		| grep -Fv $(abs_srctree)/rust/alloc \
1852		| grep -Fv $(abs_objtree)/rust/test \
1853		| grep -Fv generated \
1854		| xargs $(RUSTFMT) $(rustfmt_flags)
1855
1856rustfmtcheck: rustfmt_flags = --check
1857rustfmtcheck: rustfmt
1858
1859# IDE support targets
1860PHONY += rust-analyzer
1861rust-analyzer:
1862	$(Q)$(MAKE) $(build)=rust $@
1863
1864# Misc
1865# ---------------------------------------------------------------------------
1866
1867PHONY += misc-check
1868misc-check:
1869	$(Q)$(srctree)/scripts/misc-check
1870
1871all: misc-check
1872
1873PHONY += scripts_gdb
1874scripts_gdb: prepare0
1875	$(Q)$(MAKE) $(build)=scripts/gdb
1876	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1877
1878ifdef CONFIG_GDB_SCRIPTS
1879all: scripts_gdb
1880endif
1881
1882else # KBUILD_EXTMOD
1883
1884filechk_kernel.release = echo $(KERNELRELEASE)
1885
1886###
1887# External module support.
1888# When building external modules the kernel used as basis is considered
1889# read-only, and no consistency checks are made and the make
1890# system is not used on the basis kernel. If updates are required
1891# in the basis kernel ordinary make commands (without M=...) must be used.
1892
1893# We are always building only modules.
1894KBUILD_BUILTIN :=
1895KBUILD_MODULES := 1
1896
1897build-dir := $(KBUILD_EXTMOD)
1898
1899compile_commands.json: $(extmod_prefix)compile_commands.json
1900PHONY += compile_commands.json
1901
1902clean-dirs := $(KBUILD_EXTMOD)
1903clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1904	$(KBUILD_EXTMOD)/compile_commands.json $(KBUILD_EXTMOD)/.thinlto-cache
1905
1906PHONY += prepare
1907# now expand this into a simple variable to reduce the cost of shell evaluations
1908prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT)
1909prepare:
1910	@if [ "$(CC_VERSION_TEXT)" != "$(CONFIG_CC_VERSION_TEXT)" ]; then \
1911		echo >&2 "warning: the compiler differs from the one used to build the kernel"; \
1912		echo >&2 "  The kernel was built by: $(CONFIG_CC_VERSION_TEXT)"; \
1913		echo >&2 "  You are using:           $(CC_VERSION_TEXT)"; \
1914	fi
1915
1916PHONY += help
1917help:
1918	@echo  '  Building external modules.'
1919	@echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1920	@echo  ''
1921	@echo  '  modules         - default target, build the module(s)'
1922	@echo  '  modules_install - install the module'
1923	@echo  '  clean           - remove generated files in module directory only'
1924	@echo  ''
1925
1926endif # KBUILD_EXTMOD
1927
1928# ---------------------------------------------------------------------------
1929# Modules
1930
1931PHONY += modules modules_install modules_prepare
1932
1933ifdef CONFIG_MODULES
1934
1935$(MODORDER): $(build-dir)
1936	@:
1937
1938# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
1939# This is solely useful to speed up test compiles.
1940modules: modpost
1941ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1942	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1943endif
1944
1945PHONY += modules_check
1946modules_check: $(MODORDER)
1947	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1948
1949quiet_cmd_depmod = DEPMOD  $(MODLIB)
1950      cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1951                   $(KERNELRELEASE)
1952
1953modules_install:
1954	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1955	$(call cmd,depmod)
1956
1957else # CONFIG_MODULES
1958
1959# Modules not configured
1960# ---------------------------------------------------------------------------
1961
1962modules modules_install:
1963	@echo >&2 '***'
1964	@echo >&2 '*** The present kernel configuration has modules disabled.'
1965	@echo >&2 '*** To use the module feature, please run "make menuconfig" etc.'
1966	@echo >&2 '*** to enable CONFIG_MODULES.'
1967	@echo >&2 '***'
1968	@exit 1
1969
1970KBUILD_MODULES :=
1971
1972endif # CONFIG_MODULES
1973
1974PHONY += modpost
1975modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \
1976	 $(if $(KBUILD_MODULES), modules_check)
1977	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1978
1979# Single targets
1980# ---------------------------------------------------------------------------
1981# To build individual files in subdirectories, you can do like this:
1982#
1983#   make foo/bar/baz.s
1984#
1985# The supported suffixes for single-target are listed in 'single-targets'
1986#
1987# To build only under specific subdirectories, you can do like this:
1988#
1989#   make foo/bar/baz/
1990
1991ifdef single-build
1992
1993# .ko is special because modpost is needed
1994single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1995single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \
1996		$(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko)))
1997
1998$(single-ko): single_modules
1999	@:
2000$(single-no-ko): $(build-dir)
2001	@:
2002
2003# Remove MODORDER when done because it is not the real one.
2004PHONY += single_modules
2005single_modules: $(single-no-ko) modules_prepare
2006	$(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$(m:%.ko=%.o);) } > $(MODORDER)
2007	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
2008ifneq ($(KBUILD_MODPOST_NOFINAL),1)
2009	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
2010endif
2011	$(Q)rm -f $(MODORDER)
2012
2013single-goals := $(addprefix $(build-dir)/, $(single-no-ko))
2014
2015KBUILD_MODULES := 1
2016
2017endif
2018
2019# Preset locale variables to speed up the build process. Limit locale
2020# tweaks to this spot to avoid wrong language settings when running
2021# make menuconfig etc.
2022# Error messages still appears in the original language
2023PHONY += $(build-dir)
2024$(build-dir): prepare
2025	$(Q)$(MAKE) $(build)=$@ need-builtin=1 need-modorder=1 $(single-goals)
2026
2027clean-dirs := $(addprefix _clean_, $(clean-dirs))
2028PHONY += $(clean-dirs) clean
2029$(clean-dirs):
2030	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
2031
2032clean: $(clean-dirs)
2033	$(call cmd,rmfiles)
2034	@find $(or $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
2035		\( -name '*.[aios]' -o -name '*.rsi' -o -name '*.ko' -o -name '.*.cmd' \
2036		-o -name '*.ko.*' \
2037		-o -name '*.dtb' -o -name '*.dtbo' \
2038		-o -name '*.dtb.S' -o -name '*.dtbo.S' \
2039		-o -name '*.dt.yaml' \
2040		-o -name '*.dwo' -o -name '*.lst' \
2041		-o -name '*.su' -o -name '*.mod' -o -name '*.usyms' \
2042		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
2043		-o -name '*.lex.c' -o -name '*.tab.[ch]' \
2044		-o -name '*.asn1.[ch]' \
2045		-o -name '*.symtypes' -o -name 'modules.order' \
2046		-o -name '*.c.[012]*.*' \
2047		-o -name '*.ll' \
2048		-o -name '*.gcno' \
2049		-o -name '*.*.symversions' \) -type f -print \
2050		-o -name '.tmp_*' -print \
2051		| xargs rm -rf
2052
2053# Generate tags for editors
2054# ---------------------------------------------------------------------------
2055quiet_cmd_tags = GEN     $@
2056      cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
2057
2058tags TAGS cscope gtags: FORCE
2059	$(call cmd,tags)
2060
2061# Script to generate missing namespace dependencies
2062# ---------------------------------------------------------------------------
2063
2064PHONY += nsdeps
2065nsdeps: export KBUILD_NSDEPS=1
2066nsdeps: modules
2067	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
2068
2069# Clang Tooling
2070# ---------------------------------------------------------------------------
2071
2072quiet_cmd_gen_compile_commands = GEN     $@
2073      cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
2074
2075$(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
2076	$(if $(KBUILD_EXTMOD),, vmlinux.a $(KBUILD_VMLINUX_LIBS)) \
2077	$(if $(CONFIG_MODULES), $(MODORDER)) FORCE
2078	$(call if_changed,gen_compile_commands)
2079
2080targets += $(extmod_prefix)compile_commands.json
2081
2082PHONY += clang-tidy clang-analyzer
2083
2084ifdef CONFIG_CC_IS_CLANG
2085quiet_cmd_clang_tools = CHECK   $<
2086      cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
2087
2088clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
2089	$(call cmd,clang_tools)
2090else
2091clang-tidy clang-analyzer:
2092	@echo "$@ requires CC=clang" >&2
2093	@false
2094endif
2095
2096# Scripts to check various things for consistency
2097# ---------------------------------------------------------------------------
2098
2099PHONY += includecheck versioncheck coccicheck export_report
2100
2101includecheck:
2102	find $(srctree)/* $(RCS_FIND_IGNORE) \
2103		-name '*.[hcS]' -type f -print | sort \
2104		| xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
2105
2106versioncheck:
2107	find $(srctree)/* $(RCS_FIND_IGNORE) \
2108		-name '*.[hcS]' -type f -print | sort \
2109		| xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
2110
2111coccicheck:
2112	$(Q)$(BASH) $(srctree)/scripts/$@
2113
2114export_report:
2115	$(PERL) $(srctree)/scripts/export_report.pl
2116
2117PHONY += checkstack kernelrelease kernelversion image_name
2118
2119# UML needs a little special treatment here.  It wants to use the host
2120# toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
2121# else wants $(ARCH), including people doing cross-builds, which means
2122# that $(SUBARCH) doesn't work here.
2123ifeq ($(ARCH), um)
2124CHECKSTACK_ARCH := $(SUBARCH)
2125else
2126CHECKSTACK_ARCH := $(ARCH)
2127endif
2128checkstack:
2129	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
2130	$(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
2131
2132kernelrelease:
2133	@$(filechk_kernel.release)
2134
2135kernelversion:
2136	@echo $(KERNELVERSION)
2137
2138image_name:
2139	@echo $(KBUILD_IMAGE)
2140
2141quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
2142      cmd_rmfiles = rm -rf $(rm-files)
2143
2144# read saved command lines for existing targets
2145existing-targets := $(wildcard $(sort $(targets)))
2146
2147-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
2148
2149endif # config-build
2150endif # mixed-build
2151endif # need-sub-make
2152
2153PHONY += FORCE
2154FORCE:
2155
2156# Declare the contents of the PHONY variable as phony.  We keep that
2157# information in a variable so we can use it in if_changed and friends.
2158.PHONY: $(PHONY)
2159