xref: /linux/Makefile (revision e991acf1bce7a428794514cbbe216973c9c0a3c8)
1# SPDX-License-Identifier: GPL-2.0
2VERSION = 6
3PATCHLEVEL = 16
4SUBLEVEL = 0
5EXTRAVERSION =
6NAME = Baby Opossum Posse
7
8# *DOCUMENTATION*
9# To see a list of typical targets execute "make help"
10# More info can be located in ./README
11# Comments in this file are targeted only to the developer, do not
12# expect to learn how to build the kernel reading this file.
13
14ifeq ($(filter output-sync,$(.FEATURES)),)
15$(error GNU Make >= 4.0 is required. Your Make version is $(MAKE_VERSION))
16endif
17
18$(if $(filter __%, $(MAKECMDGOALS)), \
19	$(error targets prefixed with '__' are only for internal use))
20
21# That's our default target when none is given on the command line
22PHONY := __all
23__all:
24
25# We are using a recursive build, so we need to do a little thinking
26# to get the ordering right.
27#
28# Most importantly: sub-Makefiles should only ever modify files in
29# their own directory. If in some directory we have a dependency on
30# a file in another dir (which doesn't happen often, but it's often
31# unavoidable when linking the built-in.a targets which finally
32# turn into vmlinux), we will call a sub make in that other dir, and
33# after that we are sure that everything which is in that other dir
34# is now up to date.
35#
36# The only cases where we need to modify files which have global
37# effects are thus separated out and done before the recursive
38# descending is started. They are now explicitly listed as the
39# prepare rule.
40
41this-makefile := $(lastword $(MAKEFILE_LIST))
42abs_srctree := $(realpath $(dir $(this-makefile)))
43abs_output := $(CURDIR)
44
45ifneq ($(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, $(KBUILD_VERBOSE)),)
90  quiet =
91  Q =
92endif
93
94# If the user is running make -s (silent mode), suppress echoing of
95# commands
96ifneq ($(findstring s,$(firstword -$(MAKEFLAGS))),)
97quiet=silent_
98override KBUILD_VERBOSE :=
99endif
100
101export quiet Q KBUILD_VERBOSE
102
103# Call a source code checker (by default, "sparse") as part of the
104# C compilation.
105#
106# Use 'make C=1' to enable checking of only re-compiled files.
107# Use 'make C=2' to enable checking of *all* source files, regardless
108# of whether they are re-compiled or not.
109#
110# See the file "Documentation/dev-tools/sparse.rst" for more details,
111# including where to get the "sparse" utility.
112
113ifeq ("$(origin C)", "command line")
114  KBUILD_CHECKSRC = $(C)
115endif
116ifndef KBUILD_CHECKSRC
117  KBUILD_CHECKSRC = 0
118endif
119
120export KBUILD_CHECKSRC
121
122# Enable "clippy" (a linter) as part of the Rust compilation.
123#
124# Use 'make CLIPPY=1' to enable it.
125ifeq ("$(origin CLIPPY)", "command line")
126  KBUILD_CLIPPY := $(CLIPPY)
127endif
128
129export KBUILD_CLIPPY
130
131# Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
132# directory of external module to build. Setting M= takes precedence.
133ifeq ("$(origin M)", "command line")
134  KBUILD_EXTMOD := $(M)
135endif
136
137ifeq ("$(origin MO)", "command line")
138  KBUILD_EXTMOD_OUTPUT := $(MO)
139endif
140
141$(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 $(KBUILD_EXTMOD).)
150endif
151
152export KBUILD_EXTMOD
153
154ifeq ("$(origin W)", "command line")
155  KBUILD_EXTRA_WARN := $(W)
156endif
157
158export KBUILD_EXTRA_WARN
159
160# Kbuild will save output files in the current working directory.
161# This does not need to match to the root of the kernel source tree.
162#
163# For example, you can do this:
164#
165#  cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
166#
167# If you want to save output files in a different location, there are
168# two syntaxes to specify it.
169#
170# 1) O=
171# Use "make O=dir/to/store/output/files/"
172#
173# 2) Set KBUILD_OUTPUT
174# Set the environment variable KBUILD_OUTPUT to point to the output directory.
175# export KBUILD_OUTPUT=dir/to/store/output/files/; make
176#
177# The O= assignment takes precedence over the KBUILD_OUTPUT environment
178# variable.
179
180ifeq ("$(origin O)", "command line")
181  KBUILD_OUTPUT := $(O)
182endif
183
184ifdef KBUILD_EXTMOD
185    ifdef KBUILD_OUTPUT
186        objtree := $(realpath $(KBUILD_OUTPUT))
187        $(if $(objtree),,$(error specified kernel directory "$(KBUILD_OUTPUT)" does not exist))
188    else
189        objtree := $(abs_srctree)
190    endif
191    # If Make is invoked from the kernel directory (either kernel
192    # source directory or kernel build directory), external modules
193    # are built in $(KBUILD_EXTMOD) for backward compatibility,
194    # otherwise, built in the current directory.
195    output := $(or $(KBUILD_EXTMOD_OUTPUT),$(if $(filter $(CURDIR),$(objtree) $(abs_srctree)),$(KBUILD_EXTMOD)))
196    # KBUILD_EXTMOD might be a relative path. Remember its absolute path before
197    # Make changes the working directory.
198    srcroot := $(realpath $(KBUILD_EXTMOD))
199    $(if $(srcroot),,$(error specified external module directory "$(KBUILD_EXTMOD)" does not exist))
200else
201    objtree := .
202    output := $(KBUILD_OUTPUT)
203endif
204
205export objtree srcroot
206
207# Do we want to change the working directory?
208ifneq ($(output),)
209# $(realpath ...) gets empty if the path does not exist. Run 'mkdir -p' first.
210$(shell mkdir -p "$(output)")
211# $(realpath ...) resolves symlinks
212abs_output := $(realpath $(output))
213$(if $(abs_output),,$(error failed to create output directory "$(output)"))
214endif
215
216ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
217$(error source directory cannot contain spaces or colons)
218endif
219
220export sub_make_done := 1
221
222endif # sub_make_done
223
224ifeq ($(abs_output),$(CURDIR))
225# Suppress "Entering directory ..." if we are at the final work directory.
226no-print-directory := --no-print-directory
227else
228# Recursion to show "Entering directory ..."
229need-sub-make := 1
230endif
231
232ifeq ($(filter --no-print-directory, $(MAKEFLAGS)),)
233# If --no-print-directory is unset, recurse once again to set it.
234# You may end up recursing into __sub-make twice. This is needed due to the
235# behavior change in GNU Make 4.4.1.
236need-sub-make := 1
237endif
238
239ifeq ($(need-sub-make),1)
240
241PHONY += $(MAKECMDGOALS) __sub-make
242
243$(filter-out $(this-makefile), $(MAKECMDGOALS)) __all: __sub-make
244	@:
245
246# Invoke a second make in the output directory, passing relevant variables
247__sub-make:
248	$(Q)$(MAKE) $(no-print-directory) -C $(abs_output) \
249	-f $(abs_srctree)/Makefile $(MAKECMDGOALS)
250
251else # need-sub-make
252
253# We process the rest of the Makefile if this is the final invocation of make
254
255ifndef KBUILD_EXTMOD
256srcroot := $(abs_srctree)
257endif
258
259ifeq ($(srcroot),$(CURDIR))
260building_out_of_srctree :=
261else
262export building_out_of_srctree := 1
263endif
264
265ifdef KBUILD_ABS_SRCTREE
266    # Do nothing. Use the absolute path.
267else ifeq ($(srcroot),$(CURDIR))
268    # Building in the source.
269    srcroot := .
270else ifeq ($(srcroot)/,$(dir $(CURDIR)))
271    # Building in a subdirectory of the source.
272    srcroot := ..
273endif
274
275export srctree := $(if $(KBUILD_EXTMOD),$(abs_srctree),$(srcroot))
276
277ifdef building_out_of_srctree
278export VPATH := $(srcroot)
279else
280VPATH :=
281endif
282
283# To make sure we do not include .config for any of the *config targets
284# catch them early, and hand them over to scripts/kconfig/Makefile
285# It is allowed to specify more targets when calling make, including
286# mixing *config targets and build targets.
287# For example 'make oldconfig all'.
288# Detect when mixed targets is specified, and make a second invocation
289# of make so .config is not included in this case either (for *config).
290
291version_h := include/generated/uapi/linux/version.h
292
293clean-targets := %clean mrproper cleandocs
294no-dot-config-targets := $(clean-targets) \
295			 cscope gtags TAGS tags help% %docs check% coccicheck \
296			 $(version_h) headers headers_% archheaders archscripts \
297			 %asm-generic kernelversion %src-pkg dt_binding_check \
298			 outputmakefile rustavailable rustfmt rustfmtcheck
299no-sync-config-targets := $(no-dot-config-targets) %install modules_sign kernelrelease \
300			  image_name
301single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.rsi %.s %/
302
303config-build	:=
304mixed-build	:=
305need-config	:= 1
306may-sync-config	:= 1
307single-build	:=
308
309ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
310    ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
311        need-config :=
312    endif
313endif
314
315ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
316    ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
317        may-sync-config :=
318    endif
319endif
320
321need-compiler := $(may-sync-config)
322
323ifneq ($(KBUILD_EXTMOD),)
324    may-sync-config :=
325endif
326
327ifeq ($(KBUILD_EXTMOD),)
328    ifneq ($(filter %config,$(MAKECMDGOALS)),)
329        config-build := 1
330        ifneq ($(words $(MAKECMDGOALS)),1)
331            mixed-build := 1
332        endif
333    endif
334endif
335
336# We cannot build single targets and the others at the same time
337ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
338    single-build := 1
339    ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
340        mixed-build := 1
341    endif
342endif
343
344# For "make -j clean all", "make -j mrproper defconfig all", etc.
345ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
346    ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
347        mixed-build := 1
348    endif
349endif
350
351# install and modules_install need also be processed one by one
352ifneq ($(filter install,$(MAKECMDGOALS)),)
353    ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
354        mixed-build := 1
355    endif
356endif
357
358ifdef mixed-build
359# ===========================================================================
360# We're called with mixed targets (*config and build targets).
361# Handle them one by one.
362
363PHONY += $(MAKECMDGOALS) __build_one_by_one
364
365$(MAKECMDGOALS): __build_one_by_one
366	@:
367
368__build_one_by_one:
369	$(Q)set -e; \
370	for i in $(MAKECMDGOALS); do \
371		$(MAKE) -f $(srctree)/Makefile $$i; \
372	done
373
374else # !mixed-build
375
376include $(srctree)/scripts/Kbuild.include
377
378# Read KERNELRELEASE from include/config/kernel.release (if it exists)
379KERNELRELEASE = $(call read-file, $(objtree)/include/config/kernel.release)
380KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
381export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
382
383include $(srctree)/scripts/subarch.include
384
385# Cross compiling and selecting different set of gcc/bin-utils
386# ---------------------------------------------------------------------------
387#
388# When performing cross compilation for other architectures ARCH shall be set
389# to the target architecture. (See arch/* for the possibilities).
390# ARCH can be set during invocation of make:
391# make ARCH=arm64
392# Another way is to have ARCH set in the environment.
393# The default ARCH is the host where make is executed.
394
395# CROSS_COMPILE specify the prefix used for all executables used
396# during compilation. Only gcc and related bin-utils executables
397# are prefixed with $(CROSS_COMPILE).
398# CROSS_COMPILE can be set on the command line
399# make CROSS_COMPILE=aarch64-linux-gnu-
400# Alternatively CROSS_COMPILE can be set in the environment.
401# Default value for CROSS_COMPILE is not to prefix executables
402# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
403ARCH		?= $(SUBARCH)
404
405# Architecture as present in compile.h
406UTS_MACHINE 	:= $(ARCH)
407SRCARCH 	:= $(ARCH)
408
409# Additional ARCH settings for x86
410ifeq ($(ARCH),i386)
411        SRCARCH := x86
412endif
413ifeq ($(ARCH),x86_64)
414        SRCARCH := x86
415endif
416
417# Additional ARCH settings for sparc
418ifeq ($(ARCH),sparc32)
419       SRCARCH := sparc
420endif
421ifeq ($(ARCH),sparc64)
422       SRCARCH := sparc
423endif
424
425# Additional ARCH settings for parisc
426ifeq ($(ARCH),parisc64)
427       SRCARCH := parisc
428endif
429
430export cross_compiling :=
431ifneq ($(SRCARCH),$(SUBARCH))
432cross_compiling := 1
433endif
434
435KCONFIG_CONFIG	?= .config
436export KCONFIG_CONFIG
437
438# SHELL used by kbuild
439CONFIG_SHELL := sh
440
441HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
442HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
443HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
444
445ifneq ($(LLVM),)
446ifneq ($(filter %/,$(LLVM)),)
447LLVM_PREFIX := $(LLVM)
448else ifneq ($(filter -%,$(LLVM)),)
449LLVM_SUFFIX := $(LLVM)
450endif
451
452HOSTCC	= $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
453HOSTCXX	= $(LLVM_PREFIX)clang++$(LLVM_SUFFIX)
454else
455HOSTCC	= gcc
456HOSTCXX	= g++
457endif
458HOSTRUSTC = rustc
459HOSTPKG_CONFIG	= pkg-config
460
461# the KERNELDOC macro needs to be exported, as scripts/Makefile.build
462# has a logic to call it
463KERNELDOC       = $(srctree)/scripts/kernel-doc.py
464export KERNELDOC
465
466KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
467			 -O2 -fomit-frame-pointer -std=gnu11
468KBUILD_USERCFLAGS  := $(KBUILD_USERHOSTCFLAGS) $(USERCFLAGS)
469KBUILD_USERLDFLAGS := $(USERLDFLAGS)
470
471# These flags apply to all Rust code in the tree, including the kernel and
472# host programs.
473export rust_common_flags := --edition=2021 \
474			    -Zbinary_dep_depinfo=y \
475			    -Astable_features \
476			    -Dnon_ascii_idents \
477			    -Dunsafe_op_in_unsafe_fn \
478			    -Wmissing_docs \
479			    -Wrust_2018_idioms \
480			    -Wunreachable_pub \
481			    -Wclippy::all \
482			    -Wclippy::as_ptr_cast_mut \
483			    -Wclippy::as_underscore \
484			    -Wclippy::cast_lossless \
485			    -Wclippy::ignored_unit_patterns \
486			    -Wclippy::mut_mut \
487			    -Wclippy::needless_bitwise_bool \
488			    -Aclippy::needless_lifetimes \
489			    -Wclippy::no_mangle_with_rust_abi \
490			    -Wclippy::ptr_as_ptr \
491			    -Wclippy::ptr_cast_constness \
492			    -Wclippy::ref_as_ptr \
493			    -Wclippy::undocumented_unsafe_blocks \
494			    -Wclippy::unnecessary_safety_comment \
495			    -Wclippy::unnecessary_safety_doc \
496			    -Wrustdoc::missing_crate_level_docs \
497			    -Wrustdoc::unescaped_backticks
498
499KBUILD_HOSTCFLAGS   := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) \
500		       $(HOSTCFLAGS) -I $(srctree)/scripts/include
501KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS) \
502		       -I $(srctree)/scripts/include
503KBUILD_HOSTRUSTFLAGS := $(rust_common_flags) -O -Cstrip=debuginfo \
504			-Zallow-features= $(HOSTRUSTFLAGS)
505KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
506KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
507KBUILD_PROCMACROLDFLAGS := $(or $(PROCMACROLDFLAGS),$(KBUILD_HOSTLDFLAGS))
508
509# Make variables (CC, etc...)
510CPP		= $(CC) -E
511ifneq ($(LLVM),)
512CC		= $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
513LD		= $(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX)
514AR		= $(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX)
515NM		= $(LLVM_PREFIX)llvm-nm$(LLVM_SUFFIX)
516OBJCOPY		= $(LLVM_PREFIX)llvm-objcopy$(LLVM_SUFFIX)
517OBJDUMP		= $(LLVM_PREFIX)llvm-objdump$(LLVM_SUFFIX)
518READELF		= $(LLVM_PREFIX)llvm-readelf$(LLVM_SUFFIX)
519STRIP		= $(LLVM_PREFIX)llvm-strip$(LLVM_SUFFIX)
520else
521CC		= $(CROSS_COMPILE)gcc
522LD		= $(CROSS_COMPILE)ld
523AR		= $(CROSS_COMPILE)ar
524NM		= $(CROSS_COMPILE)nm
525OBJCOPY		= $(CROSS_COMPILE)objcopy
526OBJDUMP		= $(CROSS_COMPILE)objdump
527READELF		= $(CROSS_COMPILE)readelf
528STRIP		= $(CROSS_COMPILE)strip
529endif
530RUSTC		= rustc
531RUSTDOC		= rustdoc
532RUSTFMT		= rustfmt
533CLIPPY_DRIVER	= clippy-driver
534BINDGEN		= bindgen
535PAHOLE		= pahole
536RESOLVE_BTFIDS	= $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
537LEX		= flex
538YACC		= bison
539AWK		= awk
540INSTALLKERNEL  := installkernel
541PERL		= perl
542PYTHON3		= python3
543CHECK		= sparse
544BASH		= bash
545KGZIP		= gzip
546KBZIP2		= bzip2
547KLZOP		= lzop
548LZMA		= lzma
549LZ4		= lz4
550XZ		= xz
551ZSTD		= zstd
552
553CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
554		  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
555NOSTDINC_FLAGS :=
556CFLAGS_MODULE   =
557RUSTFLAGS_MODULE =
558AFLAGS_MODULE   =
559LDFLAGS_MODULE  =
560CFLAGS_KERNEL	=
561RUSTFLAGS_KERNEL =
562AFLAGS_KERNEL	=
563LDFLAGS_vmlinux =
564
565# Use USERINCLUDE when you must reference the UAPI directories only.
566USERINCLUDE    := \
567		-I$(srctree)/arch/$(SRCARCH)/include/uapi \
568		-I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
569		-I$(srctree)/include/uapi \
570		-I$(objtree)/include/generated/uapi \
571                -include $(srctree)/include/linux/compiler-version.h \
572                -include $(srctree)/include/linux/kconfig.h
573
574# Use LINUXINCLUDE when you must reference the include/ directory.
575# Needed to be compatible with the O= option
576LINUXINCLUDE    := \
577		-I$(srctree)/arch/$(SRCARCH)/include \
578		-I$(objtree)/arch/$(SRCARCH)/include/generated \
579		-I$(srctree)/include \
580		-I$(objtree)/include \
581		$(USERINCLUDE)
582
583KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
584
585KBUILD_CFLAGS :=
586KBUILD_CFLAGS += -std=gnu11
587KBUILD_CFLAGS += -fshort-wchar
588KBUILD_CFLAGS += -funsigned-char
589KBUILD_CFLAGS += -fno-common
590KBUILD_CFLAGS += -fno-PIE
591KBUILD_CFLAGS += -fno-strict-aliasing
592
593KBUILD_CPPFLAGS := -D__KERNEL__
594KBUILD_RUSTFLAGS := $(rust_common_flags) \
595		    -Cpanic=abort -Cembed-bitcode=n -Clto=n \
596		    -Cforce-unwind-tables=n -Ccodegen-units=1 \
597		    -Csymbol-mangling-version=v0 \
598		    -Crelocation-model=static \
599		    -Zfunction-sections=n \
600		    -Wclippy::float_arithmetic
601
602KBUILD_AFLAGS_KERNEL :=
603KBUILD_CFLAGS_KERNEL :=
604KBUILD_RUSTFLAGS_KERNEL :=
605KBUILD_AFLAGS_MODULE  := -DMODULE
606KBUILD_CFLAGS_MODULE  := -DMODULE
607KBUILD_RUSTFLAGS_MODULE := --cfg MODULE
608KBUILD_LDFLAGS_MODULE :=
609KBUILD_LDFLAGS :=
610CLANG_FLAGS :=
611
612ifeq ($(KBUILD_CLIPPY),1)
613	RUSTC_OR_CLIPPY_QUIET := CLIPPY
614	RUSTC_OR_CLIPPY = $(CLIPPY_DRIVER)
615else
616	RUSTC_OR_CLIPPY_QUIET := RUSTC
617	RUSTC_OR_CLIPPY = $(RUSTC)
618endif
619
620# Allows the usage of unstable features in stable compilers.
621export RUSTC_BOOTSTRAP := 1
622
623# Allows finding `.clippy.toml` in out-of-srctree builds.
624export CLIPPY_CONF_DIR := $(srctree)
625
626export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG
627export RUSTC RUSTDOC RUSTFMT RUSTC_OR_CLIPPY_QUIET RUSTC_OR_CLIPPY BINDGEN
628export HOSTRUSTC KBUILD_HOSTRUSTFLAGS
629export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
630export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
631export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
632export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS KBUILD_PROCMACROLDFLAGS LDFLAGS_MODULE
633export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS
634
635export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
636export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
637export KBUILD_RUSTFLAGS RUSTFLAGS_KERNEL RUSTFLAGS_MODULE
638export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
639export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_RUSTFLAGS_MODULE KBUILD_LDFLAGS_MODULE
640export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL KBUILD_RUSTFLAGS_KERNEL
641
642# Files to ignore in find ... statements
643
644export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
645			  -name CVS -o -name .pc -o -name .hg -o -name .git \) \
646			  -prune -o
647
648# ===========================================================================
649# Rules shared between *config targets and build targets
650
651# Basic helpers built in scripts/basic/
652PHONY += scripts_basic
653scripts_basic:
654	$(Q)$(MAKE) $(build)=scripts/basic
655
656PHONY += outputmakefile
657ifdef building_out_of_srctree
658# Before starting out-of-tree build, make sure the source tree is clean.
659# outputmakefile generates a Makefile in the output directory, if using a
660# separate output directory. This allows convenient use of make in the
661# output directory.
662# At the same time when output Makefile generated, generate .gitignore to
663# ignore whole output directory
664
665ifdef KBUILD_EXTMOD
666print_env_for_makefile = \
667	echo "export KBUILD_OUTPUT = $(objtree)"; \
668	echo "export KBUILD_EXTMOD = $(realpath $(srcroot))" ; \
669	echo "export KBUILD_EXTMOD_OUTPUT = $(CURDIR)"
670else
671print_env_for_makefile = \
672	echo "export KBUILD_OUTPUT = $(CURDIR)"
673endif
674
675quiet_cmd_makefile = GEN     Makefile
676      cmd_makefile = { \
677	echo "\# Automatically generated by $(abs_srctree)/Makefile: don't edit"; \
678	$(print_env_for_makefile); \
679	echo "include $(abs_srctree)/Makefile"; \
680	} > Makefile
681
682outputmakefile:
683ifeq ($(KBUILD_EXTMOD),)
684	@if [ -f $(srctree)/.config -o \
685		 -d $(srctree)/include/config -o \
686		 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
687		echo >&2 "***"; \
688		echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
689		echo >&2 "*** in $(abs_srctree)";\
690		echo >&2 "***"; \
691		false; \
692	fi
693else
694	@if [ -f $(srcroot)/modules.order ]; then \
695		echo >&2 "***"; \
696		echo >&2 "*** The external module source tree is not clean."; \
697		echo >&2 "*** Please run 'make -C $(abs_srctree) M=$(realpath $(srcroot)) clean'"; \
698		echo >&2 "***"; \
699		false; \
700	fi
701endif
702	$(Q)ln -fsn $(srcroot) source
703	$(call cmd,makefile)
704	$(Q)test -e .gitignore || \
705	{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
706endif
707
708# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
709# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
710# CC_VERSION_TEXT and RUSTC_VERSION_TEXT are referenced from Kconfig (so they
711# need export), and from include/config/auto.conf.cmd to detect the compiler
712# upgrade.
713CC_VERSION_TEXT = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1))
714RUSTC_VERSION_TEXT = $(subst $(pound),,$(shell $(RUSTC) --version 2>/dev/null))
715
716ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
717include $(srctree)/scripts/Makefile.clang
718endif
719
720# Include this also for config targets because some architectures need
721# cc-cross-prefix to determine CROSS_COMPILE.
722ifdef need-compiler
723include $(srctree)/scripts/Makefile.compiler
724endif
725
726ifdef config-build
727# ===========================================================================
728# *config targets only - make sure prerequisites are updated, and descend
729# in scripts/kconfig to make the *config target
730
731# Read arch-specific Makefile to set KBUILD_DEFCONFIG as needed.
732# KBUILD_DEFCONFIG may point out an alternative default configuration
733# used for 'make defconfig'
734include $(srctree)/arch/$(SRCARCH)/Makefile
735export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT RUSTC_VERSION_TEXT
736
737config: outputmakefile scripts_basic FORCE
738	$(Q)$(MAKE) $(build)=scripts/kconfig $@
739
740%config: outputmakefile scripts_basic FORCE
741	$(Q)$(MAKE) $(build)=scripts/kconfig $@
742
743else #!config-build
744# ===========================================================================
745# Build targets only - this includes vmlinux, arch-specific targets, clean
746# targets and others. In general all targets except *config targets.
747
748# If building an external module we do not care about the all: rule
749# but instead __all depend on modules
750PHONY += all
751ifeq ($(KBUILD_EXTMOD),)
752__all: all
753else
754__all: modules
755endif
756
757targets :=
758
759# Decide whether to build built-in, modular, or both.
760# Normally, just do built-in.
761
762KBUILD_MODULES :=
763KBUILD_BUILTIN := y
764
765# If we have only "make modules", don't compile built-in objects.
766ifeq ($(MAKECMDGOALS),modules)
767  KBUILD_BUILTIN :=
768endif
769
770# If we have "make <whatever> modules", compile modules
771# in addition to whatever we do anyway.
772# Just "make" or "make all" shall build modules as well
773
774ifneq ($(filter all modules nsdeps compile_commands.json clang-%,$(MAKECMDGOALS)),)
775  KBUILD_MODULES := y
776endif
777
778ifeq ($(MAKECMDGOALS),)
779  KBUILD_MODULES := y
780endif
781
782export KBUILD_MODULES KBUILD_BUILTIN
783
784ifdef need-config
785include $(objtree)/include/config/auto.conf
786endif
787
788ifeq ($(KBUILD_EXTMOD),)
789# Objects we will link into vmlinux / subdirs we need to visit
790core-y		:=
791drivers-y	:=
792libs-y		:= lib/
793endif # KBUILD_EXTMOD
794
795# The all: target is the default when no target is given on the
796# command line.
797# This allow a user to issue only 'make' to build a kernel including modules
798# Defaults to vmlinux, but the arch makefile usually adds further targets
799all: vmlinux
800
801CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage
802ifdef CONFIG_CC_IS_GCC
803CFLAGS_GCOV	+= -fno-tree-loop-im
804endif
805export CFLAGS_GCOV
806
807# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
808ifdef CONFIG_FUNCTION_TRACER
809  CC_FLAGS_FTRACE := -pg
810endif
811
812include $(srctree)/arch/$(SRCARCH)/Makefile
813
814ifdef need-config
815ifdef may-sync-config
816# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
817# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
818# because some architectures define CROSS_COMPILE there.
819include include/config/auto.conf.cmd
820
821$(KCONFIG_CONFIG):
822	@echo >&2 '***'
823	@echo >&2 '*** Configuration file "$@" not found!'
824	@echo >&2 '***'
825	@echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
826	@echo >&2 '*** "make menuconfig" or "make xconfig").'
827	@echo >&2 '***'
828	@/bin/false
829
830# The actual configuration files used during the build are stored in
831# include/generated/ and include/config/. Update them if .config is newer than
832# include/config/auto.conf (which mirrors .config).
833#
834# This exploits the 'multi-target pattern rule' trick.
835# The syncconfig should be executed only once to make all the targets.
836# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
837#
838# Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
839# so you cannot notice that Kconfig is waiting for the user input.
840%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h %/generated/rustc_cfg: $(KCONFIG_CONFIG)
841	$(Q)$(kecho) "  SYNC    $@"
842	$(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
843else # !may-sync-config
844# External modules and some install targets need include/generated/autoconf.h
845# and include/config/auto.conf but do not care if they are up-to-date.
846# Use auto.conf to show the error message
847
848checked-configs := $(addprefix $(objtree)/, include/generated/autoconf.h include/generated/rustc_cfg include/config/auto.conf)
849missing-configs := $(filter-out $(wildcard $(checked-configs)), $(checked-configs))
850
851ifdef missing-configs
852PHONY += $(objtree)/include/config/auto.conf
853
854$(objtree)/include/config/auto.conf:
855	@echo   >&2 '***'
856	@echo   >&2 '***  ERROR: Kernel configuration is invalid. The following files are missing:'
857	@printf >&2 '***    - %s\n' $(missing-configs)
858	@echo   >&2 '***  Run "make oldconfig && make prepare" on kernel source to fix it.'
859	@echo   >&2 '***'
860	@/bin/false
861endif
862
863endif # may-sync-config
864endif # need-config
865
866KBUILD_CFLAGS	+= -fno-delete-null-pointer-checks
867
868ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
869KBUILD_CFLAGS += -O2
870KBUILD_RUSTFLAGS += -Copt-level=2
871else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
872KBUILD_CFLAGS += -Os
873KBUILD_RUSTFLAGS += -Copt-level=s
874endif
875
876# Always set `debug-assertions` and `overflow-checks` because their default
877# depends on `opt-level` and `debug-assertions`, respectively.
878KBUILD_RUSTFLAGS += -Cdebug-assertions=$(if $(CONFIG_RUST_DEBUG_ASSERTIONS),y,n)
879KBUILD_RUSTFLAGS += -Coverflow-checks=$(if $(CONFIG_RUST_OVERFLOW_CHECKS),y,n)
880
881# Tell gcc to never replace conditional load with a non-conditional one
882ifdef CONFIG_CC_IS_GCC
883# gcc-10 renamed --param=allow-store-data-races=0 to
884# -fno-allow-store-data-races.
885KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
886KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
887endif
888
889ifdef CONFIG_READABLE_ASM
890# Disable optimizations that make assembler listings hard to read.
891# reorder blocks reorders the control in the function
892# ipa clone creates specialized cloned functions
893# partial inlining inlines only parts of functions
894KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
895endif
896
897stackp-flags-y                                    := -fno-stack-protector
898stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
899stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
900
901KBUILD_CFLAGS += $(stackp-flags-y)
902
903KBUILD_RUSTFLAGS-$(CONFIG_WERROR) += -Dwarnings
904KBUILD_RUSTFLAGS += $(KBUILD_RUSTFLAGS-y)
905
906ifdef CONFIG_FRAME_POINTER
907KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
908KBUILD_RUSTFLAGS += -Cforce-frame-pointers=y
909else
910# Some targets (ARM with Thumb2, for example), can't be built with frame
911# pointers.  For those, we don't have FUNCTION_TRACER automatically
912# select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
913# incompatible with -fomit-frame-pointer with current GCC, so we don't use
914# -fomit-frame-pointer with FUNCTION_TRACER.
915# In the Rust target specification, "frame-pointer" is set explicitly
916# to "may-omit".
917ifndef CONFIG_FUNCTION_TRACER
918KBUILD_CFLAGS	+= -fomit-frame-pointer
919endif
920endif
921
922# Initialize all stack variables with a 0xAA pattern.
923ifdef CONFIG_INIT_STACK_ALL_PATTERN
924KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
925endif
926
927# Initialize all stack variables with a zero value.
928ifdef CONFIG_INIT_STACK_ALL_ZERO
929KBUILD_CFLAGS	+= -ftrivial-auto-var-init=zero
930ifdef CONFIG_CC_HAS_AUTO_VAR_INIT_ZERO_ENABLER
931# https://github.com/llvm/llvm-project/issues/44842
932CC_AUTO_VAR_INIT_ZERO_ENABLER := -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
933export CC_AUTO_VAR_INIT_ZERO_ENABLER
934KBUILD_CFLAGS	+= $(CC_AUTO_VAR_INIT_ZERO_ENABLER)
935endif
936endif
937
938# Explicitly clear padding bits during variable initialization
939KBUILD_CFLAGS += $(call cc-option,-fzero-init-padding-bits=all)
940
941# While VLAs have been removed, GCC produces unreachable stack probes
942# for the randomize_kstack_offset feature. Disable it for all compilers.
943KBUILD_CFLAGS	+= $(call cc-option, -fno-stack-clash-protection)
944
945# Clear used registers at func exit (to reduce data lifetime and ROP gadgets).
946ifdef CONFIG_ZERO_CALL_USED_REGS
947KBUILD_CFLAGS	+= -fzero-call-used-regs=used-gpr
948endif
949
950ifdef CONFIG_FUNCTION_TRACER
951ifdef CONFIG_FTRACE_MCOUNT_USE_CC
952  CC_FLAGS_FTRACE	+= -mrecord-mcount
953  ifdef CONFIG_HAVE_NOP_MCOUNT
954    ifeq ($(call cc-option-yn, -mnop-mcount),y)
955      CC_FLAGS_FTRACE	+= -mnop-mcount
956      CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
957    endif
958  endif
959endif
960ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
961  ifdef CONFIG_HAVE_OBJTOOL_NOP_MCOUNT
962    CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
963  endif
964endif
965ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
966  ifdef CONFIG_HAVE_C_RECORDMCOUNT
967    BUILD_C_RECORDMCOUNT := y
968    export BUILD_C_RECORDMCOUNT
969  endif
970endif
971ifdef CONFIG_HAVE_FENTRY
972  # s390-linux-gnu-gcc did not support -mfentry until gcc-9.
973  ifeq ($(call cc-option-yn, -mfentry),y)
974    CC_FLAGS_FTRACE	+= -mfentry
975    CC_FLAGS_USING	+= -DCC_USING_FENTRY
976  endif
977endif
978export CC_FLAGS_FTRACE
979KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
980KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
981endif
982
983# We trigger additional mismatches with less inlining
984ifdef CONFIG_DEBUG_SECTION_MISMATCH
985KBUILD_CFLAGS += -fno-inline-functions-called-once
986endif
987
988# `rustc`'s `-Zfunction-sections` applies to data too (as of 1.59.0).
989ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
990KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
991KBUILD_RUSTFLAGS_KERNEL += -Zfunction-sections=y
992LDFLAGS_vmlinux += --gc-sections
993endif
994
995ifdef CONFIG_SHADOW_CALL_STACK
996ifndef CONFIG_DYNAMIC_SCS
997CC_FLAGS_SCS	:= -fsanitize=shadow-call-stack
998KBUILD_CFLAGS	+= $(CC_FLAGS_SCS)
999KBUILD_RUSTFLAGS += -Zsanitizer=shadow-call-stack
1000endif
1001export CC_FLAGS_SCS
1002endif
1003
1004ifdef CONFIG_LTO_CLANG
1005ifdef CONFIG_LTO_CLANG_THIN
1006CC_FLAGS_LTO	:= -flto=thin -fsplit-lto-unit
1007else
1008CC_FLAGS_LTO	:= -flto
1009endif
1010CC_FLAGS_LTO	+= -fvisibility=hidden
1011
1012# Limit inlining across translation units to reduce binary size
1013KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
1014endif
1015
1016ifdef CONFIG_LTO
1017KBUILD_CFLAGS	+= -fno-lto $(CC_FLAGS_LTO)
1018KBUILD_AFLAGS	+= -fno-lto
1019export CC_FLAGS_LTO
1020endif
1021
1022ifdef CONFIG_CFI_CLANG
1023CC_FLAGS_CFI	:= -fsanitize=kcfi
1024ifdef CONFIG_CFI_ICALL_NORMALIZE_INTEGERS
1025	CC_FLAGS_CFI	+= -fsanitize-cfi-icall-experimental-normalize-integers
1026endif
1027ifdef CONFIG_FINEIBT_BHI
1028	CC_FLAGS_CFI	+= -fsanitize-kcfi-arity
1029endif
1030ifdef CONFIG_RUST
1031	# Always pass -Zsanitizer-cfi-normalize-integers as CONFIG_RUST selects
1032	# CONFIG_CFI_ICALL_NORMALIZE_INTEGERS.
1033	RUSTC_FLAGS_CFI   := -Zsanitizer=kcfi -Zsanitizer-cfi-normalize-integers
1034	KBUILD_RUSTFLAGS += $(RUSTC_FLAGS_CFI)
1035	export RUSTC_FLAGS_CFI
1036endif
1037KBUILD_CFLAGS	+= $(CC_FLAGS_CFI)
1038export CC_FLAGS_CFI
1039endif
1040
1041# Architectures can define flags to add/remove for floating-point support
1042CC_FLAGS_FPU	+= -D_LINUX_FPU_COMPILATION_UNIT
1043export CC_FLAGS_FPU
1044export CC_FLAGS_NO_FPU
1045
1046ifneq ($(CONFIG_FUNCTION_ALIGNMENT),0)
1047# Set the minimal function alignment. Use the newer GCC option
1048# -fmin-function-alignment if it is available, or fall back to -falign-funtions.
1049# See also CONFIG_CC_HAS_SANE_FUNCTION_ALIGNMENT.
1050ifdef CONFIG_CC_HAS_MIN_FUNCTION_ALIGNMENT
1051KBUILD_CFLAGS += -fmin-function-alignment=$(CONFIG_FUNCTION_ALIGNMENT)
1052else
1053KBUILD_CFLAGS += -falign-functions=$(CONFIG_FUNCTION_ALIGNMENT)
1054endif
1055endif
1056
1057# arch Makefile may override CC so keep this after arch Makefile is included
1058NOSTDINC_FLAGS += -nostdinc
1059
1060# To gain proper coverage for CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE,
1061# the kernel uses only C99 flexible arrays for dynamically sized trailing
1062# arrays. Enforce this for everything that may examine structure sizes and
1063# perform bounds checking.
1064KBUILD_CFLAGS += $(call cc-option, -fstrict-flex-arrays=3)
1065
1066# disable invalid "can't wrap" optimizations for signed / pointers
1067KBUILD_CFLAGS	+= -fno-strict-overflow
1068
1069# Make sure -fstack-check isn't enabled (like gentoo apparently did)
1070KBUILD_CFLAGS  += -fno-stack-check
1071
1072# conserve stack if available
1073ifdef CONFIG_CC_IS_GCC
1074KBUILD_CFLAGS   += -fconserve-stack
1075endif
1076
1077# Ensure compilers do not transform certain loops into calls to wcslen()
1078KBUILD_CFLAGS += -fno-builtin-wcslen
1079
1080# change __FILE__ to the relative path to the source directory
1081ifdef building_out_of_srctree
1082KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srcroot)/=)
1083endif
1084
1085# include additional Makefiles when needed
1086include-y			:= scripts/Makefile.extrawarn
1087include-$(CONFIG_DEBUG_INFO)	+= scripts/Makefile.debug
1088include-$(CONFIG_DEBUG_INFO_BTF)+= scripts/Makefile.btf
1089include-$(CONFIG_KASAN)		+= scripts/Makefile.kasan
1090include-$(CONFIG_KCSAN)		+= scripts/Makefile.kcsan
1091include-$(CONFIG_KMSAN)		+= scripts/Makefile.kmsan
1092include-$(CONFIG_UBSAN)		+= scripts/Makefile.ubsan
1093include-$(CONFIG_KCOV)		+= scripts/Makefile.kcov
1094include-$(CONFIG_RANDSTRUCT)	+= scripts/Makefile.randstruct
1095include-$(CONFIG_KSTACK_ERASE)	+= scripts/Makefile.kstack_erase
1096include-$(CONFIG_AUTOFDO_CLANG)	+= scripts/Makefile.autofdo
1097include-$(CONFIG_PROPELLER_CLANG)	+= scripts/Makefile.propeller
1098include-$(CONFIG_GCC_PLUGINS)	+= scripts/Makefile.gcc-plugins
1099
1100include $(addprefix $(srctree)/, $(include-y))
1101
1102# scripts/Makefile.gcc-plugins is intentionally included last.
1103# Do not add $(call cc-option,...) below this line. When you build the kernel
1104# from the clean source tree, the GCC plugins do not exist at this point.
1105
1106# Add user supplied CPPFLAGS, AFLAGS, CFLAGS and RUSTFLAGS as the last assignments
1107KBUILD_CPPFLAGS += $(KCPPFLAGS)
1108KBUILD_AFLAGS   += $(KAFLAGS)
1109KBUILD_CFLAGS   += $(KCFLAGS)
1110KBUILD_RUSTFLAGS += $(KRUSTFLAGS)
1111
1112KBUILD_LDFLAGS_MODULE += --build-id=sha1
1113LDFLAGS_vmlinux += --build-id=sha1
1114
1115KBUILD_LDFLAGS	+= -z noexecstack
1116ifeq ($(CONFIG_LD_IS_BFD),y)
1117KBUILD_LDFLAGS	+= $(call ld-option,--no-warn-rwx-segments)
1118endif
1119
1120ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1121LDFLAGS_vmlinux	+= -X
1122endif
1123
1124ifeq ($(CONFIG_RELR),y)
1125# ld.lld before 15 did not support -z pack-relative-relocs.
1126LDFLAGS_vmlinux	+= $(call ld-option,--pack-dyn-relocs=relr,-z pack-relative-relocs)
1127endif
1128
1129# We never want expected sections to be placed heuristically by the
1130# linker. All sections should be explicitly named in the linker script.
1131ifdef CONFIG_LD_ORPHAN_WARN
1132LDFLAGS_vmlinux += --orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL)
1133endif
1134
1135ifneq ($(CONFIG_ARCH_VMLINUX_NEEDS_RELOCS),)
1136LDFLAGS_vmlinux	+= --emit-relocs --discard-none
1137endif
1138
1139# Align the bit size of userspace programs with the kernel
1140KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS))
1141KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS))
1142
1143# userspace programs are linked via the compiler, use the correct linker
1144ifeq ($(CONFIG_CC_IS_CLANG)$(CONFIG_LD_IS_LLD),yy)
1145KBUILD_USERLDFLAGS += --ld-path=$(LD)
1146endif
1147
1148# make the checker run with the right architecture
1149CHECKFLAGS += --arch=$(ARCH)
1150
1151# insure the checker run with the right endianness
1152CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1153
1154# the checker needs the correct machine size
1155CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1156
1157# Default kernel image to build when no specific target is given.
1158# KBUILD_IMAGE may be overruled on the command line or
1159# set in the environment
1160# Also any assignments in arch/$(ARCH)/Makefile take precedence over
1161# this default value
1162export KBUILD_IMAGE ?= vmlinux
1163
1164#
1165# INSTALL_PATH specifies where to place the updated kernel and system map
1166# images. Default is /boot, but you can set it to other values
1167export	INSTALL_PATH ?= /boot
1168
1169#
1170# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1171# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1172# an argument if needed. Otherwise it defaults to the kernel install path
1173#
1174export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1175
1176#
1177# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1178# relocations required by build roots.  This is not defined in the
1179# makefile but the argument can be passed to make if needed.
1180#
1181
1182MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1183export MODLIB
1184
1185PHONY += prepare0
1186
1187ifeq ($(KBUILD_EXTMOD),)
1188
1189build-dir	:= .
1190clean-dirs	:= $(sort . Documentation \
1191		     $(patsubst %/,%,$(filter %/, $(core-) \
1192			$(drivers-) $(libs-))))
1193
1194export ARCH_CORE	:= $(core-y)
1195export ARCH_LIB		:= $(filter %/, $(libs-y))
1196export ARCH_DRIVERS	:= $(drivers-y) $(drivers-m)
1197# Externally visible symbols (used by link-vmlinux.sh)
1198
1199KBUILD_VMLINUX_OBJS := built-in.a $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1200KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1201
1202export KBUILD_VMLINUX_LIBS
1203export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1204
1205ifdef CONFIG_TRIM_UNUSED_KSYMS
1206# For the kernel to actually contain only the needed exported symbols,
1207# we have to build modules as well to determine what those symbols are.
1208KBUILD_MODULES := y
1209endif
1210
1211# '$(AR) mPi' needs 'T' to workaround the bug of llvm-ar <= 14
1212quiet_cmd_ar_vmlinux.a = AR      $@
1213      cmd_ar_vmlinux.a = \
1214	rm -f $@; \
1215	$(AR) cDPrST $@ $(KBUILD_VMLINUX_OBJS); \
1216	$(AR) mPiT $$($(AR) t $@ | sed -n 1p) $@ $$($(AR) t $@ | grep -F -f $(srctree)/scripts/head-object-list.txt)
1217
1218targets += vmlinux.a
1219vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt FORCE
1220	$(call if_changed,ar_vmlinux.a)
1221
1222PHONY += vmlinux_o
1223vmlinux_o: vmlinux.a $(KBUILD_VMLINUX_LIBS)
1224	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o
1225
1226vmlinux.o modules.builtin.modinfo modules.builtin: vmlinux_o
1227	@:
1228
1229PHONY += vmlinux
1230# LDFLAGS_vmlinux in the top Makefile defines linker flags for the top vmlinux,
1231# not for decompressors. LDFLAGS_vmlinux in arch/*/boot/compressed/Makefile is
1232# unrelated; the decompressors just happen to have the same base name,
1233# arch/*/boot/compressed/vmlinux.
1234# Export LDFLAGS_vmlinux only to scripts/Makefile.vmlinux.
1235#
1236# _LDFLAGS_vmlinux is a workaround for the 'private export' bug:
1237#   https://savannah.gnu.org/bugs/?61463
1238# For Make > 4.4, the following simple code will work:
1239#  vmlinux: private export LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1240vmlinux: private _LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1241vmlinux: export LDFLAGS_vmlinux = $(_LDFLAGS_vmlinux)
1242vmlinux: vmlinux.o $(KBUILD_LDS) modpost
1243	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux
1244
1245# The actual objects are generated when descending,
1246# make sure no implicit rule kicks in
1247$(sort $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)): . ;
1248
1249ifeq ($(origin KERNELRELEASE),file)
1250filechk_kernel.release = $(srctree)/scripts/setlocalversion $(srctree)
1251else
1252filechk_kernel.release = echo $(KERNELRELEASE)
1253endif
1254
1255# Store (new) KERNELRELEASE string in include/config/kernel.release
1256include/config/kernel.release: FORCE
1257	$(call filechk,kernel.release)
1258
1259# Additional helpers built in scripts/
1260# Carefully list dependencies so we do not try to build scripts twice
1261# in parallel
1262PHONY += scripts
1263scripts: scripts_basic scripts_dtc
1264	$(Q)$(MAKE) $(build)=$(@)
1265
1266# Things we need to do before we recursively start building the kernel
1267# or the modules are listed in "prepare".
1268# A multi level approach is used. prepareN is processed before prepareN-1.
1269# archprepare is used in arch Makefiles and when processed asm symlink,
1270# version.h and scripts_basic is processed / created.
1271
1272PHONY += prepare archprepare
1273
1274archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1275	asm-generic $(version_h) include/generated/utsrelease.h \
1276	include/generated/compile.h include/generated/autoconf.h \
1277	include/generated/rustc_cfg remove-stale-files
1278
1279prepare0: archprepare
1280	$(Q)$(MAKE) $(build)=scripts/mod
1281	$(Q)$(MAKE) $(build)=. prepare
1282
1283# All the preparing..
1284prepare: prepare0
1285ifdef CONFIG_RUST
1286	+$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh
1287	$(Q)$(MAKE) $(build)=rust
1288endif
1289
1290PHONY += remove-stale-files
1291remove-stale-files:
1292	$(Q)$(srctree)/scripts/remove-stale-files
1293
1294# Support for using generic headers in asm-generic
1295asm-generic := -f $(srctree)/scripts/Makefile.asm-headers obj
1296
1297PHONY += asm-generic uapi-asm-generic
1298asm-generic: uapi-asm-generic
1299	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1300	generic=include/asm-generic
1301uapi-asm-generic:
1302	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1303	generic=include/uapi/asm-generic
1304
1305# Generate some files
1306# ---------------------------------------------------------------------------
1307
1308# KERNELRELEASE can change from a few different places, meaning version.h
1309# needs to be updated, so this check is forced on all builds
1310
1311uts_len := 64
1312define filechk_utsrelease.h
1313	if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1314	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1315	  exit 1;                                                         \
1316	fi;                                                               \
1317	echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1318endef
1319
1320define filechk_version.h
1321	if [ $(SUBLEVEL) -gt 255 ]; then                                 \
1322		echo \#define LINUX_VERSION_CODE $(shell                 \
1323		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1324	else                                                             \
1325		echo \#define LINUX_VERSION_CODE $(shell                 \
1326		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1327	fi;                                                              \
1328	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
1329	((c) > 255 ? 255 : (c)))';                                       \
1330	echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
1331	echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
1332	echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1333endef
1334
1335$(version_h): private PATCHLEVEL := $(or $(PATCHLEVEL), 0)
1336$(version_h): private SUBLEVEL := $(or $(SUBLEVEL), 0)
1337$(version_h): FORCE
1338	$(call filechk,version.h)
1339
1340include/generated/utsrelease.h: include/config/kernel.release FORCE
1341	$(call filechk,utsrelease.h)
1342
1343filechk_compile.h = $(srctree)/scripts/mkcompile_h \
1344	"$(UTS_MACHINE)" "$(CONFIG_CC_VERSION_TEXT)" "$(LD)"
1345
1346include/generated/compile.h: FORCE
1347	$(call filechk,compile.h)
1348
1349PHONY += headerdep
1350headerdep:
1351	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1352	$(srctree)/scripts/headerdep.pl -I$(srctree)/include
1353
1354# ---------------------------------------------------------------------------
1355# Kernel headers
1356
1357#Default location for installed headers
1358export INSTALL_HDR_PATH = $(objtree)/usr
1359
1360quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1361      cmd_headers_install = \
1362	mkdir -p $(INSTALL_HDR_PATH); \
1363	rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1364	usr/include $(INSTALL_HDR_PATH)
1365
1366PHONY += headers_install
1367headers_install: headers
1368	$(call cmd,headers_install)
1369
1370PHONY += archheaders archscripts
1371
1372hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1373
1374PHONY += headers
1375headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders
1376ifdef HEADER_ARCH
1377	$(Q)$(MAKE) -f $(srctree)/Makefile HEADER_ARCH= SRCARCH=$(HEADER_ARCH) headers
1378else
1379	$(Q)$(MAKE) $(hdr-inst)=include/uapi
1380	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1381endif
1382
1383ifdef CONFIG_HEADERS_INSTALL
1384prepare: headers
1385endif
1386
1387PHONY += scripts_unifdef
1388scripts_unifdef: scripts_basic
1389	$(Q)$(MAKE) $(build)=scripts scripts/unifdef
1390
1391PHONY += scripts_gen_packed_field_checks
1392scripts_gen_packed_field_checks: scripts_basic
1393	$(Q)$(MAKE) $(build)=scripts scripts/gen_packed_field_checks
1394
1395# ---------------------------------------------------------------------------
1396# Install
1397
1398# Many distributions have the custom install script, /sbin/installkernel.
1399# If DKMS is installed, 'make install' will eventually recurse back
1400# to this Makefile to build and install external modules.
1401# Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
1402
1403quiet_cmd_install = INSTALL $(INSTALL_PATH)
1404      cmd_install = unset sub_make_done; $(srctree)/scripts/install.sh
1405
1406# ---------------------------------------------------------------------------
1407# vDSO install
1408
1409PHONY += vdso_install
1410vdso_install: export INSTALL_FILES = $(vdso-install-y)
1411vdso_install:
1412	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vdsoinst
1413
1414# ---------------------------------------------------------------------------
1415# Tools
1416
1417ifdef CONFIG_OBJTOOL
1418prepare: tools/objtool
1419endif
1420
1421ifdef CONFIG_BPF
1422ifdef CONFIG_DEBUG_INFO_BTF
1423prepare: tools/bpf/resolve_btfids
1424endif
1425endif
1426
1427# The tools build system is not a part of Kbuild and tends to introduce
1428# its own unique issues. If you need to integrate a new tool into Kbuild,
1429# please consider locating that tool outside the tools/ tree and using the
1430# standard Kbuild "hostprogs" syntax instead of adding a new tools/* entry
1431# here. See Documentation/kbuild/makefiles.rst for details.
1432
1433PHONY += resolve_btfids_clean
1434
1435resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1436
1437# tools/bpf/resolve_btfids directory might not exist
1438# in output directory, skip its clean in that case
1439resolve_btfids_clean:
1440ifneq ($(wildcard $(resolve_btfids_O)),)
1441	$(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1442endif
1443
1444tools/: FORCE
1445	$(Q)mkdir -p $(objtree)/tools
1446	$(Q)$(MAKE) LDFLAGS= O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1447
1448tools/%: FORCE
1449	$(Q)mkdir -p $(objtree)/tools
1450	$(Q)$(MAKE) LDFLAGS= O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1451
1452# ---------------------------------------------------------------------------
1453# Kernel selftest
1454
1455PHONY += kselftest
1456kselftest: headers
1457	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1458
1459kselftest-%: headers FORCE
1460	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1461
1462PHONY += kselftest-merge
1463kselftest-merge:
1464	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1465	$(Q)find $(srctree)/tools/testing/selftests -name config -o -name config.$(UTS_MACHINE) | \
1466		xargs $(srctree)/scripts/kconfig/merge_config.sh -y -m $(objtree)/.config
1467	$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1468
1469# ---------------------------------------------------------------------------
1470# Devicetree files
1471
1472ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1473dtstree := arch/$(SRCARCH)/boot/dts
1474endif
1475
1476ifneq ($(dtstree),)
1477
1478%.dtb: dtbs_prepare
1479	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1480
1481%.dtbo: dtbs_prepare
1482	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1483
1484PHONY += dtbs dtbs_prepare dtbs_install dtbs_check
1485dtbs: dtbs_prepare
1486	$(Q)$(MAKE) $(build)=$(dtstree) need-dtbslist=1
1487
1488# include/config/kernel.release is actually needed when installing DTBs because
1489# INSTALL_DTBS_PATH contains $(KERNELRELEASE). However, we do not want to make
1490# dtbs_install depend on it as dtbs_install may run as root.
1491dtbs_prepare: include/config/kernel.release scripts_dtc
1492
1493ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1494export CHECK_DTBS=y
1495endif
1496
1497ifneq ($(CHECK_DTBS),)
1498dtbs_prepare: dt_binding_schemas
1499endif
1500
1501dtbs_check: dtbs
1502
1503dtbs_install:
1504	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.dtbinst obj=$(dtstree)
1505
1506ifdef CONFIG_OF_EARLY_FLATTREE
1507all: dtbs
1508endif
1509
1510ifdef CONFIG_GENERIC_BUILTIN_DTB
1511vmlinux: dtbs
1512endif
1513
1514endif
1515
1516PHONY += scripts_dtc
1517scripts_dtc: scripts_basic
1518	$(Q)$(MAKE) $(build)=scripts/dtc
1519
1520ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1521export CHECK_DTBS=y
1522endif
1523
1524PHONY += dt_binding_check dt_binding_schemas
1525dt_binding_check: dt_binding_schemas scripts_dtc
1526	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1527
1528dt_binding_schemas:
1529	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1530
1531PHONY += dt_compatible_check
1532dt_compatible_check: dt_binding_schemas
1533	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1534
1535# ---------------------------------------------------------------------------
1536# Modules
1537
1538ifdef CONFIG_MODULES
1539
1540# By default, build modules as well
1541
1542all: modules
1543
1544# When we're building modules with modversions, we need to consider
1545# the built-in objects during the descend as well, in order to
1546# make sure the checksums are up to date before we record them.
1547ifdef CONFIG_MODVERSIONS
1548  KBUILD_BUILTIN := y
1549endif
1550
1551# Build modules
1552#
1553
1554# *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFO_BTF_MODULES
1555# is an exception.
1556ifdef CONFIG_DEBUG_INFO_BTF_MODULES
1557KBUILD_BUILTIN := y
1558modules: vmlinux
1559endif
1560
1561modules: modules_prepare
1562
1563# Target to prepare building external modules
1564modules_prepare: prepare
1565	$(Q)$(MAKE) $(build)=scripts scripts/module.lds
1566
1567endif # CONFIG_MODULES
1568
1569###
1570# Cleaning is done on three levels.
1571# make clean     Delete most generated files
1572#                Leave enough to build external modules
1573# make mrproper  Delete the current configuration, and all generated files
1574# make distclean Remove editor backup files, patch leftover files and the like
1575
1576# Directories & files removed with 'make clean'
1577CLEAN_FILES += vmlinux.symvers modules-only.symvers \
1578	       modules.builtin modules.builtin.modinfo modules.nsdeps \
1579	       modules.builtin.ranges vmlinux.o.map vmlinux.unstripped \
1580	       compile_commands.json rust/test \
1581	       rust-project.json .vmlinux.objs .vmlinux.export.c \
1582               .builtin-dtbs-list .builtin-dtb.S
1583
1584# Directories & files removed with 'make mrproper'
1585MRPROPER_FILES += include/config include/generated          \
1586		  arch/$(SRCARCH)/include/generated .objdiff \
1587		  debian snap tar-install PKGBUILD pacman \
1588		  .config .config.old .version \
1589		  Module.symvers \
1590		  certs/signing_key.pem \
1591		  certs/x509.genkey \
1592		  vmlinux-gdb.py \
1593		  rpmbuild \
1594		  rust/libmacros.so rust/libmacros.dylib
1595
1596# clean - Delete most, but leave enough to build external modules
1597#
1598clean: private rm-files := $(CLEAN_FILES)
1599
1600PHONY += archclean vmlinuxclean
1601
1602vmlinuxclean:
1603	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1604	$(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1605
1606clean: archclean vmlinuxclean resolve_btfids_clean
1607
1608# mrproper - Delete all generated files, including .config
1609#
1610mrproper: private rm-files := $(MRPROPER_FILES)
1611mrproper-dirs      := $(addprefix _mrproper_,scripts)
1612
1613PHONY += $(mrproper-dirs) mrproper
1614$(mrproper-dirs):
1615	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1616
1617mrproper: clean $(mrproper-dirs)
1618	$(call cmd,rmfiles)
1619	@find . $(RCS_FIND_IGNORE) \
1620		\( -name '*.rmeta' \) \
1621		-type f -print | xargs rm -f
1622
1623# distclean
1624#
1625PHONY += distclean
1626
1627distclean: mrproper
1628	@find . $(RCS_FIND_IGNORE) \
1629		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1630		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
1631		-o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1632		-o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1633		-type f -print | xargs rm -f
1634
1635
1636# Packaging of the kernel to various formats
1637# ---------------------------------------------------------------------------
1638
1639%src-pkg: FORCE
1640	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1641%pkg: include/config/kernel.release FORCE
1642	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1643
1644# Brief documentation of the typical targets used
1645# ---------------------------------------------------------------------------
1646
1647boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1648boards := $(sort $(notdir $(boards)))
1649board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1650board-dirs := $(sort $(notdir $(board-dirs:/=)))
1651
1652PHONY += help
1653help:
1654	@echo  'Cleaning targets:'
1655	@echo  '  clean		  - Remove most generated files but keep the config and'
1656	@echo  '                    enough build support to build external modules'
1657	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
1658	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
1659	@echo  ''
1660	@$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1661	@echo  ''
1662	@echo  'Other generic targets:'
1663	@echo  '  all		  - Build all targets marked with [*]'
1664	@echo  '* vmlinux	  - Build the bare kernel'
1665	@echo  '* modules	  - Build all modules'
1666	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1667	@echo  '  vdso_install    - Install unstripped vdso to INSTALL_MOD_PATH (default: /)'
1668	@echo  '  dir/            - Build all files in dir and below'
1669	@echo  '  dir/file.[ois]  - Build specified target only'
1670	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1671	@echo  '                    (requires compiler support for LLVM assembly generation)'
1672	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1673	@echo  '                    (requires a recent binutils and recent build (System.map))'
1674	@echo  '  dir/file.ko     - Build module including final link'
1675	@echo  '  modules_prepare - Set up for building external modules'
1676	@echo  '  tags/TAGS	  - Generate tags file for editors'
1677	@echo  '  cscope	  - Generate cscope index'
1678	@echo  '  gtags           - Generate GNU GLOBAL index'
1679	@echo  '  kernelrelease	  - Output the release version string (use with make -s)'
1680	@echo  '  kernelversion	  - Output the version stored in Makefile (use with make -s)'
1681	@echo  '  image_name	  - Output the image name (use with make -s)'
1682	@echo  '  headers	  - Build ready-to-install UAPI headers in usr/include'
1683	@echo  '  headers_install - Install sanitised kernel UAPI headers to INSTALL_HDR_PATH'; \
1684	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1685	 echo  ''
1686	@echo  'Static analysers:'
1687	@echo  '  checkstack      - Generate a list of stack hogs and consider all functions'
1688	@echo  '                    with a stack size larger than MINSTACKSIZE (default: 100)'
1689	@echo  '  versioncheck    - Sanity check on version.h usage'
1690	@echo  '  includecheck    - Check for duplicate included header files'
1691	@echo  '  headerdep       - Detect inclusion cycles in headers'
1692	@echo  '  coccicheck      - Check with Coccinelle'
1693	@echo  '  clang-analyzer  - Check with clang static analyzer'
1694	@echo  '  clang-tidy      - Check with clang-tidy'
1695	@echo  ''
1696	@echo  'Tools:'
1697	@echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1698	@echo  ''
1699	@echo  'Kernel selftest:'
1700	@echo  '  kselftest         - Build and run kernel selftest'
1701	@echo  '                      Build, install, and boot kernel before'
1702	@echo  '                      running kselftest on it'
1703	@echo  '                      Run as root for full coverage'
1704	@echo  '  kselftest-all     - Build kernel selftest'
1705	@echo  '  kselftest-install - Build and install kernel selftest'
1706	@echo  '  kselftest-clean   - Remove all generated kselftest files'
1707	@echo  '  kselftest-merge   - Merge all the config dependencies of'
1708	@echo  '		      kselftest to existing .config.'
1709	@echo  ''
1710	@echo  'Rust targets:'
1711	@echo  '  rustavailable   - Checks whether the Rust toolchain is'
1712	@echo  '		    available and, if not, explains why.'
1713	@echo  '  rustfmt	  - Reformat all the Rust code in the kernel'
1714	@echo  '  rustfmtcheck	  - Checks if all the Rust code in the kernel'
1715	@echo  '		    is formatted, printing a diff otherwise.'
1716	@echo  '  rustdoc	  - Generate Rust documentation'
1717	@echo  '		    (requires kernel .config)'
1718	@echo  '  rusttest        - Runs the Rust tests'
1719	@echo  '                    (requires kernel .config; downloads external repos)'
1720	@echo  '  rust-analyzer	  - Generate rust-project.json rust-analyzer support file'
1721	@echo  '		    (requires kernel .config)'
1722	@echo  '  dir/file.[os]   - Build specified target only'
1723	@echo  '  dir/file.rsi    - Build macro expanded source, similar to C preprocessing.'
1724	@echo  '                    Run with RUSTFMT=n to skip reformatting if needed.'
1725	@echo  '                    The output is not intended to be compilable.'
1726	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1727	@echo  ''
1728	@$(if $(dtstree), \
1729		echo 'Devicetree:'; \
1730		echo '* dtbs               - Build device tree blobs for enabled boards'; \
1731		echo '  dtbs_install       - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1732		echo '  dt_binding_check   - Validate device tree binding documents and examples'; \
1733		echo '  dt_binding_schemas - Build processed device tree binding schemas'; \
1734		echo '  dtbs_check         - Validate device tree source files';\
1735		echo '')
1736
1737	@echo 'Userspace tools targets:'
1738	@echo '  use "make tools/help"'
1739	@echo '  or  "cd tools; make help"'
1740	@echo  ''
1741	@echo  'Kernel packaging:'
1742	@$(MAKE) -f $(srctree)/scripts/Makefile.package help
1743	@echo  ''
1744	@echo  'Documentation targets:'
1745	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1746	@echo  ''
1747	@echo  'Architecture-specific targets ($(SRCARCH)):'
1748	@$(or $(archhelp),\
1749		echo '  No architecture-specific help defined for $(SRCARCH)')
1750	@echo  ''
1751	@$(if $(boards), \
1752		$(foreach b, $(boards), \
1753		printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1754		echo '')
1755	@$(if $(board-dirs), \
1756		$(foreach b, $(board-dirs), \
1757		printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1758		printf "  %-16s - Show all of the above\\n" help-boards; \
1759		echo '')
1760
1761	@echo  '  make V=n   [targets] 1: verbose build'
1762	@echo  '                       2: give reason for rebuild of target'
1763	@echo  '                       V=1 and V=2 can be combined with V=12'
1764	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1765	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1766	@echo  '                       (sparse by default)'
1767	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1768	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1769	@echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3,c,e where'
1770	@echo  '		1: warnings which may be relevant and do not occur too often'
1771	@echo  '		2: warnings which occur quite often but may still be relevant'
1772	@echo  '		3: more obscure warnings, can most likely be ignored'
1773	@echo  '		c: extra checks in the configuration stage (Kconfig)'
1774	@echo  '		e: warnings are being treated as errors'
1775	@echo  '		Multiple levels can be combined with W=12 or W=123'
1776	@$(if $(dtstree), \
1777		echo '  make CHECK_DTBS=1 [targets] Check all generated dtb files against schema'; \
1778		echo '         This can be applied both to "dtbs" and to individual "foo.dtb" targets' ; \
1779		)
1780	@echo  ''
1781	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
1782	@echo  'For further info see the ./README file'
1783
1784
1785help-board-dirs := $(addprefix help-,$(board-dirs))
1786
1787help-boards: $(help-board-dirs)
1788
1789boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1790
1791$(help-board-dirs): help-%:
1792	@echo  'Architecture-specific targets ($(SRCARCH) $*):'
1793	@$(if $(boards-per-dir), \
1794		$(foreach b, $(boards-per-dir), \
1795		printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1796		echo '')
1797
1798
1799# Documentation targets
1800# ---------------------------------------------------------------------------
1801DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1802	       linkcheckdocs dochelp refcheckdocs texinfodocs infodocs
1803PHONY += $(DOC_TARGETS)
1804$(DOC_TARGETS):
1805	$(Q)$(MAKE) $(build)=Documentation $@
1806
1807
1808# Rust targets
1809# ---------------------------------------------------------------------------
1810
1811# "Is Rust available?" target
1812PHONY += rustavailable
1813rustavailable:
1814	+$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh && echo "Rust is available!"
1815
1816# Documentation target
1817#
1818# Using the singular to avoid running afoul of `no-dot-config-targets`.
1819PHONY += rustdoc
1820rustdoc: prepare
1821	$(Q)$(MAKE) $(build)=rust $@
1822
1823# Testing target
1824PHONY += rusttest
1825rusttest: prepare
1826	$(Q)$(MAKE) $(build)=rust $@
1827
1828# Formatting targets
1829PHONY += rustfmt rustfmtcheck
1830
1831rustfmt:
1832	$(Q)find $(srctree) $(RCS_FIND_IGNORE) \
1833		-type f -a -name '*.rs' -a ! -name '*generated*' -print \
1834		| xargs $(RUSTFMT) $(rustfmt_flags)
1835
1836rustfmtcheck: rustfmt_flags = --check
1837rustfmtcheck: rustfmt
1838
1839# Misc
1840# ---------------------------------------------------------------------------
1841
1842PHONY += misc-check
1843misc-check:
1844	$(Q)$(srctree)/scripts/misc-check
1845
1846all: misc-check
1847
1848PHONY += scripts_gdb
1849scripts_gdb: prepare0
1850	$(Q)$(MAKE) $(build)=scripts/gdb
1851	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1852
1853ifdef CONFIG_GDB_SCRIPTS
1854all: scripts_gdb
1855endif
1856
1857else # KBUILD_EXTMOD
1858
1859filechk_kernel.release = echo $(KERNELRELEASE)
1860
1861###
1862# External module support.
1863# When building external modules the kernel used as basis is considered
1864# read-only, and no consistency checks are made and the make
1865# system is not used on the basis kernel. If updates are required
1866# in the basis kernel ordinary make commands (without M=...) must be used.
1867
1868# We are always building only modules.
1869KBUILD_BUILTIN :=
1870KBUILD_MODULES := y
1871
1872build-dir := .
1873
1874clean-dirs := .
1875clean: private rm-files := Module.symvers modules.nsdeps compile_commands.json
1876
1877PHONY += prepare
1878# now expand this into a simple variable to reduce the cost of shell evaluations
1879prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT)
1880prepare:
1881	@if [ "$(CC_VERSION_TEXT)" != "$(CONFIG_CC_VERSION_TEXT)" ]; then \
1882		echo >&2 "warning: the compiler differs from the one used to build the kernel"; \
1883		echo >&2 "  The kernel was built by: $(CONFIG_CC_VERSION_TEXT)"; \
1884		echo >&2 "  You are using:           $(CC_VERSION_TEXT)"; \
1885	fi
1886
1887PHONY += help
1888help:
1889	@echo  '  Building external modules.'
1890	@echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1891	@echo  ''
1892	@echo  '  modules         - default target, build the module(s)'
1893	@echo  '  modules_install - install the module'
1894	@echo  '  clean           - remove generated files in module directory only'
1895	@echo  '  rust-analyzer	  - generate rust-project.json rust-analyzer support file'
1896	@echo  ''
1897
1898ifndef CONFIG_MODULES
1899modules modules_install: __external_modules_error
1900__external_modules_error:
1901	@echo >&2 '***'
1902	@echo >&2 '*** The present kernel disabled CONFIG_MODULES.'
1903	@echo >&2 '*** You cannot build or install external modules.'
1904	@echo >&2 '***'
1905	@false
1906endif
1907
1908endif # KBUILD_EXTMOD
1909
1910# ---------------------------------------------------------------------------
1911# Modules
1912
1913PHONY += modules modules_install modules_sign modules_prepare
1914
1915modules_install:
1916	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst \
1917	sign-only=$(if $(filter modules_install,$(MAKECMDGOALS)),,y)
1918
1919ifeq ($(CONFIG_MODULE_SIG),y)
1920# modules_sign is a subset of modules_install.
1921# 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1922modules_sign: modules_install
1923	@:
1924else
1925modules_sign:
1926	@echo >&2 '***'
1927	@echo >&2 '*** CONFIG_MODULE_SIG is disabled. You cannot sign modules.'
1928	@echo >&2 '***'
1929	@false
1930endif
1931
1932ifdef CONFIG_MODULES
1933
1934modules.order: $(build-dir)
1935	@:
1936
1937# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
1938# This is solely useful to speed up test compiles.
1939modules: modpost
1940ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1941	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1942endif
1943
1944PHONY += modules_check
1945modules_check: modules.order
1946	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1947
1948else # CONFIG_MODULES
1949
1950modules:
1951	@:
1952
1953KBUILD_MODULES :=
1954
1955endif # CONFIG_MODULES
1956
1957PHONY += modpost
1958modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \
1959	 $(if $(KBUILD_MODULES), modules_check)
1960	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1961
1962# Single targets
1963# ---------------------------------------------------------------------------
1964# To build individual files in subdirectories, you can do like this:
1965#
1966#   make foo/bar/baz.s
1967#
1968# The supported suffixes for single-target are listed in 'single-targets'
1969#
1970# To build only under specific subdirectories, you can do like this:
1971#
1972#   make foo/bar/baz/
1973
1974ifdef single-build
1975
1976# .ko is special because modpost is needed
1977single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1978single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \
1979		$(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko)))
1980
1981$(single-ko): single_modules
1982	@:
1983$(single-no-ko): $(build-dir)
1984	@:
1985
1986# Remove modules.order when done because it is not the real one.
1987PHONY += single_modules
1988single_modules: $(single-no-ko) modules_prepare
1989	$(Q){ $(foreach m, $(single-ko), echo $(m:%.ko=%.o);) } > modules.order
1990	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1991ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1992	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1993endif
1994	$(Q)rm -f modules.order
1995
1996single-goals := $(addprefix $(build-dir)/, $(single-no-ko))
1997
1998KBUILD_MODULES := y
1999
2000endif
2001
2002prepare: outputmakefile
2003
2004# Preset locale variables to speed up the build process. Limit locale
2005# tweaks to this spot to avoid wrong language settings when running
2006# make menuconfig etc.
2007# Error messages still appears in the original language
2008PHONY += $(build-dir)
2009$(build-dir): prepare
2010	$(Q)$(MAKE) $(build)=$@ need-builtin=1 need-modorder=1 $(single-goals)
2011
2012clean-dirs := $(addprefix _clean_, $(clean-dirs))
2013PHONY += $(clean-dirs) clean
2014$(clean-dirs):
2015	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
2016
2017clean: $(clean-dirs)
2018	$(call cmd,rmfiles)
2019	@find . $(RCS_FIND_IGNORE) \
2020		\( -name '*.[aios]' -o -name '*.rsi' -o -name '*.ko' -o -name '.*.cmd' \
2021		-o -name '*.ko.*' \
2022		-o -name '*.dtb' -o -name '*.dtbo' \
2023		-o -name '*.dtb.S' -o -name '*.dtbo.S' \
2024		-o -name '*.dt.yaml' -o -name 'dtbs-list' \
2025		-o -name '*.dwo' -o -name '*.lst' \
2026		-o -name '*.su' -o -name '*.mod' \
2027		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
2028		-o -name '*.lex.c' -o -name '*.tab.[ch]' \
2029		-o -name '*.asn1.[ch]' \
2030		-o -name '*.symtypes' -o -name 'modules.order' \
2031		-o -name '*.c.[012]*.*' \
2032		-o -name '*.ll' \
2033		-o -name '*.gcno' \
2034		\) -type f -print \
2035		-o -name '.tmp_*' -print \
2036		| xargs rm -rf
2037
2038# Generate tags for editors
2039# ---------------------------------------------------------------------------
2040quiet_cmd_tags = GEN     $@
2041      cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
2042
2043tags TAGS cscope gtags: FORCE
2044	$(call cmd,tags)
2045
2046# Generate rust-project.json (a file that describes the structure of non-Cargo
2047# Rust projects) for rust-analyzer (an implementation of the Language Server
2048# Protocol).
2049PHONY += rust-analyzer
2050rust-analyzer:
2051	+$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh
2052ifdef KBUILD_EXTMOD
2053# FIXME: external modules must not descend into a sub-directory of the kernel
2054	$(Q)$(MAKE) $(build)=$(objtree)/rust src=$(srctree)/rust $@
2055else
2056	$(Q)$(MAKE) $(build)=rust $@
2057endif
2058
2059# Script to generate missing namespace dependencies
2060# ---------------------------------------------------------------------------
2061
2062PHONY += nsdeps
2063nsdeps: export KBUILD_NSDEPS=1
2064nsdeps: modules
2065	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
2066
2067# Clang Tooling
2068# ---------------------------------------------------------------------------
2069
2070quiet_cmd_gen_compile_commands = GEN     $@
2071      cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
2072
2073compile_commands.json: $(srctree)/scripts/clang-tools/gen_compile_commands.py \
2074	$(if $(KBUILD_EXTMOD),, vmlinux.a $(KBUILD_VMLINUX_LIBS)) \
2075	$(if $(CONFIG_MODULES), modules.order) FORCE
2076	$(call if_changed,gen_compile_commands)
2077
2078targets += compile_commands.json
2079
2080PHONY += clang-tidy clang-analyzer
2081
2082ifdef CONFIG_CC_IS_CLANG
2083quiet_cmd_clang_tools = CHECK   $<
2084      cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
2085
2086clang-tidy clang-analyzer: compile_commands.json
2087	$(call cmd,clang_tools)
2088else
2089clang-tidy clang-analyzer:
2090	@echo "$@ requires CC=clang" >&2
2091	@false
2092endif
2093
2094# Scripts to check various things for consistency
2095# ---------------------------------------------------------------------------
2096
2097PHONY += includecheck versioncheck coccicheck
2098
2099includecheck:
2100	find $(srctree)/* $(RCS_FIND_IGNORE) \
2101		-name '*.[hcS]' -type f -print | sort \
2102		| xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
2103
2104versioncheck:
2105	find $(srctree)/* $(RCS_FIND_IGNORE) \
2106		-name '*.[hcS]' -type f -print | sort \
2107		| xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
2108
2109coccicheck:
2110	$(Q)$(BASH) $(srctree)/scripts/$@
2111
2112PHONY += checkstack kernelrelease kernelversion image_name
2113
2114# UML needs a little special treatment here.  It wants to use the host
2115# toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
2116# else wants $(ARCH), including people doing cross-builds, which means
2117# that $(SUBARCH) doesn't work here.
2118ifeq ($(ARCH), um)
2119CHECKSTACK_ARCH := $(SUBARCH)
2120else
2121CHECKSTACK_ARCH := $(ARCH)
2122endif
2123MINSTACKSIZE	?= 100
2124checkstack:
2125	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
2126	$(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH) $(MINSTACKSIZE)
2127
2128kernelrelease:
2129	@$(filechk_kernel.release)
2130
2131kernelversion:
2132	@echo $(KERNELVERSION)
2133
2134image_name:
2135	@echo $(KBUILD_IMAGE)
2136
2137PHONY += run-command
2138run-command:
2139	$(Q)$(KBUILD_RUN_COMMAND)
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