xref: /linux/Makefile (revision e30f8e61e2518a837837daa26cda3c8cc30f3226)
1# SPDX-License-Identifier: GPL-2.0
2VERSION = 6
3PATCHLEVEL = 18
4SUBLEVEL = 0
5EXTRAVERSION = -rc2
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
552TAR		= tar
553
554CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
555		  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
556NOSTDINC_FLAGS :=
557CFLAGS_MODULE   =
558RUSTFLAGS_MODULE =
559AFLAGS_MODULE   =
560LDFLAGS_MODULE  =
561CFLAGS_KERNEL	=
562RUSTFLAGS_KERNEL =
563AFLAGS_KERNEL	=
564LDFLAGS_vmlinux =
565
566# Use USERINCLUDE when you must reference the UAPI directories only.
567USERINCLUDE    := \
568		-I$(srctree)/arch/$(SRCARCH)/include/uapi \
569		-I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
570		-I$(srctree)/include/uapi \
571		-I$(objtree)/include/generated/uapi \
572                -include $(srctree)/include/linux/compiler-version.h \
573                -include $(srctree)/include/linux/kconfig.h
574
575# Use LINUXINCLUDE when you must reference the include/ directory.
576# Needed to be compatible with the O= option
577LINUXINCLUDE    := \
578		-I$(srctree)/arch/$(SRCARCH)/include \
579		-I$(objtree)/arch/$(SRCARCH)/include/generated \
580		-I$(srctree)/include \
581		-I$(objtree)/include \
582		$(USERINCLUDE)
583
584KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
585
586KBUILD_CFLAGS :=
587KBUILD_CFLAGS += -std=gnu11
588KBUILD_CFLAGS += -fshort-wchar
589KBUILD_CFLAGS += -funsigned-char
590KBUILD_CFLAGS += -fno-common
591KBUILD_CFLAGS += -fno-PIE
592KBUILD_CFLAGS += -fno-strict-aliasing
593
594KBUILD_CPPFLAGS := -D__KERNEL__
595KBUILD_RUSTFLAGS := $(rust_common_flags) \
596		    -Cpanic=abort -Cembed-bitcode=n -Clto=n \
597		    -Cforce-unwind-tables=n -Ccodegen-units=1 \
598		    -Csymbol-mangling-version=v0 \
599		    -Crelocation-model=static \
600		    -Zfunction-sections=n \
601		    -Wclippy::float_arithmetic
602
603KBUILD_AFLAGS_KERNEL :=
604KBUILD_CFLAGS_KERNEL :=
605KBUILD_RUSTFLAGS_KERNEL :=
606KBUILD_AFLAGS_MODULE  := -DMODULE
607KBUILD_CFLAGS_MODULE  := -DMODULE
608KBUILD_RUSTFLAGS_MODULE := --cfg MODULE
609KBUILD_LDFLAGS_MODULE :=
610KBUILD_LDFLAGS :=
611CLANG_FLAGS :=
612
613ifeq ($(KBUILD_CLIPPY),1)
614	RUSTC_OR_CLIPPY_QUIET := CLIPPY
615	RUSTC_OR_CLIPPY = $(CLIPPY_DRIVER)
616else
617	RUSTC_OR_CLIPPY_QUIET := RUSTC
618	RUSTC_OR_CLIPPY = $(RUSTC)
619endif
620
621# Allows the usage of unstable features in stable compilers.
622export RUSTC_BOOTSTRAP := 1
623
624# Allows finding `.clippy.toml` in out-of-srctree builds.
625export CLIPPY_CONF_DIR := $(srctree)
626
627export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG
628export RUSTC RUSTDOC RUSTFMT RUSTC_OR_CLIPPY_QUIET RUSTC_OR_CLIPPY BINDGEN
629export HOSTRUSTC KBUILD_HOSTRUSTFLAGS
630export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
631export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
632export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD TAR
633export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS KBUILD_PROCMACROLDFLAGS LDFLAGS_MODULE
634export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS
635
636export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
637export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
638export KBUILD_RUSTFLAGS RUSTFLAGS_KERNEL RUSTFLAGS_MODULE
639export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
640export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_RUSTFLAGS_MODULE KBUILD_LDFLAGS_MODULE
641export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL KBUILD_RUSTFLAGS_KERNEL
642
643# Files to ignore in find ... statements
644
645export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
646			  -name CVS -o -name .pc -o -name .hg -o -name .git \) \
647			  -prune -o
648
649# ===========================================================================
650# Rules shared between *config targets and build targets
651
652# Basic helpers built in scripts/basic/
653PHONY += scripts_basic
654scripts_basic:
655	$(Q)$(MAKE) $(build)=scripts/basic
656
657PHONY += outputmakefile
658ifdef building_out_of_srctree
659# Before starting out-of-tree build, make sure the source tree is clean.
660# outputmakefile generates a Makefile in the output directory, if using a
661# separate output directory. This allows convenient use of make in the
662# output directory.
663# At the same time when output Makefile generated, generate .gitignore to
664# ignore whole output directory
665
666ifdef KBUILD_EXTMOD
667print_env_for_makefile = \
668	echo "export KBUILD_OUTPUT = $(objtree)"; \
669	echo "export KBUILD_EXTMOD = $(realpath $(srcroot))" ; \
670	echo "export KBUILD_EXTMOD_OUTPUT = $(CURDIR)"
671else
672print_env_for_makefile = \
673	echo "export KBUILD_OUTPUT = $(CURDIR)"
674endif
675
676quiet_cmd_makefile = GEN     Makefile
677      cmd_makefile = { \
678	echo "\# Automatically generated by $(abs_srctree)/Makefile: don't edit"; \
679	$(print_env_for_makefile); \
680	echo "include $(abs_srctree)/Makefile"; \
681	} > Makefile
682
683outputmakefile:
684ifeq ($(KBUILD_EXTMOD),)
685	@if [ -f $(srctree)/.config -o \
686		 -d $(srctree)/include/config -o \
687		 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
688		echo >&2 "***"; \
689		echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
690		echo >&2 "*** in $(abs_srctree)";\
691		echo >&2 "***"; \
692		false; \
693	fi
694else
695	@if [ -f $(srcroot)/modules.order ]; then \
696		echo >&2 "***"; \
697		echo >&2 "*** The external module source tree is not clean."; \
698		echo >&2 "*** Please run 'make -C $(abs_srctree) M=$(realpath $(srcroot)) clean'"; \
699		echo >&2 "***"; \
700		false; \
701	fi
702endif
703	$(Q)ln -fsn $(srcroot) source
704	$(call cmd,makefile)
705	$(Q)test -e .gitignore || \
706	{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
707endif
708
709# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
710# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
711# CC_VERSION_TEXT and RUSTC_VERSION_TEXT are referenced from Kconfig (so they
712# need export), and from include/config/auto.conf.cmd to detect the compiler
713# upgrade.
714CC_VERSION_TEXT = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1))
715RUSTC_VERSION_TEXT = $(subst $(pound),,$(shell $(RUSTC) --version 2>/dev/null))
716
717ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
718include $(srctree)/scripts/Makefile.clang
719endif
720
721# Include this also for config targets because some architectures need
722# cc-cross-prefix to determine CROSS_COMPILE.
723ifdef need-compiler
724include $(srctree)/scripts/Makefile.compiler
725endif
726
727ifdef config-build
728# ===========================================================================
729# *config targets only - make sure prerequisites are updated, and descend
730# in scripts/kconfig to make the *config target
731
732# Read arch-specific Makefile to set KBUILD_DEFCONFIG as needed.
733# KBUILD_DEFCONFIG may point out an alternative default configuration
734# used for 'make defconfig'
735include $(srctree)/arch/$(SRCARCH)/Makefile
736export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT RUSTC_VERSION_TEXT
737
738config: outputmakefile scripts_basic FORCE
739	$(Q)$(MAKE) $(build)=scripts/kconfig $@
740
741%config: outputmakefile scripts_basic FORCE
742	$(Q)$(MAKE) $(build)=scripts/kconfig $@
743
744else #!config-build
745# ===========================================================================
746# Build targets only - this includes vmlinux, arch-specific targets, clean
747# targets and others. In general all targets except *config targets.
748
749# If building an external module we do not care about the all: rule
750# but instead __all depend on modules
751PHONY += all
752ifeq ($(KBUILD_EXTMOD),)
753__all: all
754else
755__all: modules
756endif
757
758targets :=
759
760# Decide whether to build built-in, modular, or both.
761# Normally, just do built-in.
762
763KBUILD_MODULES :=
764KBUILD_BUILTIN := y
765
766# If we have only "make modules", don't compile built-in objects.
767ifeq ($(MAKECMDGOALS),modules)
768  KBUILD_BUILTIN :=
769endif
770
771# If we have "make <whatever> modules", compile modules
772# in addition to whatever we do anyway.
773# Just "make" or "make all" shall build modules as well
774
775ifneq ($(filter all modules nsdeps compile_commands.json clang-%,$(MAKECMDGOALS)),)
776  KBUILD_MODULES := y
777endif
778
779ifeq ($(MAKECMDGOALS),)
780  KBUILD_MODULES := y
781endif
782
783export KBUILD_MODULES KBUILD_BUILTIN
784
785ifdef need-config
786include $(objtree)/include/config/auto.conf
787endif
788
789ifeq ($(KBUILD_EXTMOD),)
790# Objects we will link into vmlinux / subdirs we need to visit
791core-y		:=
792drivers-y	:=
793libs-y		:= lib/
794endif # KBUILD_EXTMOD
795
796# The all: target is the default when no target is given on the
797# command line.
798# This allow a user to issue only 'make' to build a kernel including modules
799# Defaults to vmlinux, but the arch makefile usually adds further targets
800all: vmlinux
801
802CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage
803ifdef CONFIG_CC_IS_GCC
804CFLAGS_GCOV	+= -fno-tree-loop-im
805endif
806export CFLAGS_GCOV
807
808# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
809ifdef CONFIG_FUNCTION_TRACER
810  CC_FLAGS_FTRACE := -pg
811endif
812
813ifdef CONFIG_TRACEPOINTS
814# To check for unused tracepoints (tracepoints that are defined but never
815# called), run with:
816#
817# make UT=1
818#
819# Each unused tracepoints can take up to 5KB of memory in the running kernel.
820# It is best to remove any that are not used.
821#
822# This command line option will be removed when all current unused
823# tracepoints are removed.
824
825ifeq ("$(origin UT)", "command line")
826  WARN_ON_UNUSED_TRACEPOINTS := $(UT)
827endif
828endif # CONFIG_TRACEPOINTS
829
830export WARN_ON_UNUSED_TRACEPOINTS
831
832include $(srctree)/arch/$(SRCARCH)/Makefile
833
834ifdef need-config
835ifdef may-sync-config
836# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
837# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
838# because some architectures define CROSS_COMPILE there.
839include include/config/auto.conf.cmd
840
841$(KCONFIG_CONFIG):
842	@echo >&2 '***'
843	@echo >&2 '*** Configuration file "$@" not found!'
844	@echo >&2 '***'
845	@echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
846	@echo >&2 '*** "make menuconfig" or "make xconfig").'
847	@echo >&2 '***'
848	@/bin/false
849
850# The actual configuration files used during the build are stored in
851# include/generated/ and include/config/. Update them if .config is newer than
852# include/config/auto.conf (which mirrors .config).
853#
854# This exploits the 'multi-target pattern rule' trick.
855# The syncconfig should be executed only once to make all the targets.
856# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
857#
858# Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
859# so you cannot notice that Kconfig is waiting for the user input.
860%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h %/generated/rustc_cfg: $(KCONFIG_CONFIG)
861	$(Q)$(kecho) "  SYNC    $@"
862	$(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
863else # !may-sync-config
864# External modules and some install targets need include/generated/autoconf.h
865# and include/config/auto.conf but do not care if they are up-to-date.
866# Use auto.conf to show the error message
867
868checked-configs := $(addprefix $(objtree)/, include/generated/autoconf.h include/generated/rustc_cfg include/config/auto.conf)
869missing-configs := $(filter-out $(wildcard $(checked-configs)), $(checked-configs))
870
871ifdef missing-configs
872PHONY += $(objtree)/include/config/auto.conf
873
874$(objtree)/include/config/auto.conf:
875	@echo   >&2 '***'
876	@echo   >&2 '***  ERROR: Kernel configuration is invalid. The following files are missing:'
877	@printf >&2 '***    - %s\n' $(missing-configs)
878	@echo   >&2 '***  Run "make oldconfig && make prepare" on kernel source to fix it.'
879	@echo   >&2 '***'
880	@/bin/false
881endif
882
883endif # may-sync-config
884endif # need-config
885
886KBUILD_CFLAGS	+= -fno-delete-null-pointer-checks
887
888ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
889KBUILD_CFLAGS += -O2
890KBUILD_RUSTFLAGS += -Copt-level=2
891else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
892KBUILD_CFLAGS += -Os
893KBUILD_RUSTFLAGS += -Copt-level=s
894endif
895
896# Always set `debug-assertions` and `overflow-checks` because their default
897# depends on `opt-level` and `debug-assertions`, respectively.
898KBUILD_RUSTFLAGS += -Cdebug-assertions=$(if $(CONFIG_RUST_DEBUG_ASSERTIONS),y,n)
899KBUILD_RUSTFLAGS += -Coverflow-checks=$(if $(CONFIG_RUST_OVERFLOW_CHECKS),y,n)
900
901# Tell gcc to never replace conditional load with a non-conditional one
902ifdef CONFIG_CC_IS_GCC
903# gcc-10 renamed --param=allow-store-data-races=0 to
904# -fno-allow-store-data-races.
905KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
906KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
907endif
908
909ifdef CONFIG_READABLE_ASM
910# Disable optimizations that make assembler listings hard to read.
911# reorder blocks reorders the control in the function
912# ipa clone creates specialized cloned functions
913# partial inlining inlines only parts of functions
914KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
915endif
916
917stackp-flags-y                                    := -fno-stack-protector
918stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
919stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
920
921KBUILD_CFLAGS += $(stackp-flags-y)
922
923ifdef CONFIG_FRAME_POINTER
924KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
925KBUILD_RUSTFLAGS += -Cforce-frame-pointers=y
926else
927# Some targets (ARM with Thumb2, for example), can't be built with frame
928# pointers.  For those, we don't have FUNCTION_TRACER automatically
929# select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
930# incompatible with -fomit-frame-pointer with current GCC, so we don't use
931# -fomit-frame-pointer with FUNCTION_TRACER.
932# In the Rust target specification, "frame-pointer" is set explicitly
933# to "may-omit".
934ifndef CONFIG_FUNCTION_TRACER
935KBUILD_CFLAGS	+= -fomit-frame-pointer
936endif
937endif
938
939# Initialize all stack variables with a 0xAA pattern.
940ifdef CONFIG_INIT_STACK_ALL_PATTERN
941KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
942endif
943
944# Initialize all stack variables with a zero value.
945ifdef CONFIG_INIT_STACK_ALL_ZERO
946KBUILD_CFLAGS	+= -ftrivial-auto-var-init=zero
947ifdef CONFIG_CC_HAS_AUTO_VAR_INIT_ZERO_ENABLER
948# https://github.com/llvm/llvm-project/issues/44842
949CC_AUTO_VAR_INIT_ZERO_ENABLER := -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
950export CC_AUTO_VAR_INIT_ZERO_ENABLER
951KBUILD_CFLAGS	+= $(CC_AUTO_VAR_INIT_ZERO_ENABLER)
952endif
953endif
954
955# Explicitly clear padding bits during variable initialization
956KBUILD_CFLAGS += $(call cc-option,-fzero-init-padding-bits=all)
957
958# While VLAs have been removed, GCC produces unreachable stack probes
959# for the randomize_kstack_offset feature. Disable it for all compilers.
960KBUILD_CFLAGS	+= $(call cc-option, -fno-stack-clash-protection)
961
962# Clear used registers at func exit (to reduce data lifetime and ROP gadgets).
963ifdef CONFIG_ZERO_CALL_USED_REGS
964KBUILD_CFLAGS	+= -fzero-call-used-regs=used-gpr
965endif
966
967ifdef CONFIG_FUNCTION_TRACER
968ifdef CONFIG_FTRACE_MCOUNT_USE_CC
969  CC_FLAGS_FTRACE	+= -mrecord-mcount
970  ifdef CONFIG_HAVE_NOP_MCOUNT
971    ifeq ($(call cc-option-yn, -mnop-mcount),y)
972      CC_FLAGS_FTRACE	+= -mnop-mcount
973      CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
974    endif
975  endif
976endif
977ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
978  ifdef CONFIG_HAVE_OBJTOOL_NOP_MCOUNT
979    CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
980  endif
981endif
982ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
983  ifdef CONFIG_HAVE_C_RECORDMCOUNT
984    BUILD_C_RECORDMCOUNT := y
985    export BUILD_C_RECORDMCOUNT
986  endif
987endif
988ifdef CONFIG_HAVE_FENTRY
989  # s390-linux-gnu-gcc did not support -mfentry until gcc-9.
990  ifeq ($(call cc-option-yn, -mfentry),y)
991    CC_FLAGS_FTRACE	+= -mfentry
992    CC_FLAGS_USING	+= -DCC_USING_FENTRY
993  endif
994endif
995export CC_FLAGS_FTRACE
996KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
997KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
998endif
999
1000# We trigger additional mismatches with less inlining
1001ifdef CONFIG_DEBUG_SECTION_MISMATCH
1002KBUILD_CFLAGS += -fno-inline-functions-called-once
1003endif
1004
1005# `rustc`'s `-Zfunction-sections` applies to data too (as of 1.59.0).
1006ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
1007KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
1008KBUILD_RUSTFLAGS_KERNEL += -Zfunction-sections=y
1009LDFLAGS_vmlinux += --gc-sections
1010endif
1011
1012ifdef CONFIG_SHADOW_CALL_STACK
1013ifndef CONFIG_DYNAMIC_SCS
1014CC_FLAGS_SCS	:= -fsanitize=shadow-call-stack
1015KBUILD_CFLAGS	+= $(CC_FLAGS_SCS)
1016KBUILD_RUSTFLAGS += -Zsanitizer=shadow-call-stack
1017endif
1018export CC_FLAGS_SCS
1019endif
1020
1021ifdef CONFIG_LTO_CLANG
1022ifdef CONFIG_LTO_CLANG_THIN
1023CC_FLAGS_LTO	:= -flto=thin -fsplit-lto-unit
1024else
1025CC_FLAGS_LTO	:= -flto
1026endif
1027CC_FLAGS_LTO	+= -fvisibility=hidden
1028
1029# Limit inlining across translation units to reduce binary size
1030KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
1031endif
1032
1033ifdef CONFIG_LTO
1034KBUILD_CFLAGS	+= -fno-lto $(CC_FLAGS_LTO)
1035KBUILD_AFLAGS	+= -fno-lto
1036export CC_FLAGS_LTO
1037endif
1038
1039ifdef CONFIG_CFI
1040CC_FLAGS_CFI	:= -fsanitize=kcfi
1041ifdef CONFIG_CFI_ICALL_NORMALIZE_INTEGERS
1042	CC_FLAGS_CFI	+= -fsanitize-cfi-icall-experimental-normalize-integers
1043endif
1044ifdef CONFIG_FINEIBT_BHI
1045	CC_FLAGS_CFI	+= -fsanitize-kcfi-arity
1046endif
1047ifdef CONFIG_RUST
1048	# Always pass -Zsanitizer-cfi-normalize-integers as CONFIG_RUST selects
1049	# CONFIG_CFI_ICALL_NORMALIZE_INTEGERS.
1050	RUSTC_FLAGS_CFI   := -Zsanitizer=kcfi -Zsanitizer-cfi-normalize-integers
1051	KBUILD_RUSTFLAGS += $(RUSTC_FLAGS_CFI)
1052	export RUSTC_FLAGS_CFI
1053endif
1054KBUILD_CFLAGS	+= $(CC_FLAGS_CFI)
1055export CC_FLAGS_CFI
1056endif
1057
1058# Architectures can define flags to add/remove for floating-point support
1059CC_FLAGS_FPU	+= -D_LINUX_FPU_COMPILATION_UNIT
1060export CC_FLAGS_FPU
1061export CC_FLAGS_NO_FPU
1062
1063ifneq ($(CONFIG_FUNCTION_ALIGNMENT),0)
1064# Set the minimal function alignment. Use the newer GCC option
1065# -fmin-function-alignment if it is available, or fall back to -falign-funtions.
1066# See also CONFIG_CC_HAS_SANE_FUNCTION_ALIGNMENT.
1067ifdef CONFIG_CC_HAS_MIN_FUNCTION_ALIGNMENT
1068KBUILD_CFLAGS += -fmin-function-alignment=$(CONFIG_FUNCTION_ALIGNMENT)
1069else
1070KBUILD_CFLAGS += -falign-functions=$(CONFIG_FUNCTION_ALIGNMENT)
1071endif
1072endif
1073
1074# arch Makefile may override CC so keep this after arch Makefile is included
1075NOSTDINC_FLAGS += -nostdinc
1076
1077# To gain proper coverage for CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE,
1078# the kernel uses only C99 flexible arrays for dynamically sized trailing
1079# arrays. Enforce this for everything that may examine structure sizes and
1080# perform bounds checking.
1081KBUILD_CFLAGS += $(call cc-option, -fstrict-flex-arrays=3)
1082
1083# disable invalid "can't wrap" optimizations for signed / pointers
1084KBUILD_CFLAGS	+= -fno-strict-overflow
1085
1086# Make sure -fstack-check isn't enabled (like gentoo apparently did)
1087KBUILD_CFLAGS  += -fno-stack-check
1088
1089# conserve stack if available
1090ifdef CONFIG_CC_IS_GCC
1091KBUILD_CFLAGS   += -fconserve-stack
1092endif
1093
1094# Ensure compilers do not transform certain loops into calls to wcslen()
1095KBUILD_CFLAGS += -fno-builtin-wcslen
1096
1097# change __FILE__ to the relative path to the source directory
1098ifdef building_out_of_srctree
1099KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srcroot)/=)
1100endif
1101
1102# include additional Makefiles when needed
1103include-y			:= scripts/Makefile.extrawarn
1104include-$(CONFIG_DEBUG_INFO)	+= scripts/Makefile.debug
1105include-$(CONFIG_DEBUG_INFO_BTF)+= scripts/Makefile.btf
1106include-$(CONFIG_KASAN)		+= scripts/Makefile.kasan
1107include-$(CONFIG_KCSAN)		+= scripts/Makefile.kcsan
1108include-$(CONFIG_KMSAN)		+= scripts/Makefile.kmsan
1109include-$(CONFIG_UBSAN)		+= scripts/Makefile.ubsan
1110include-$(CONFIG_KCOV)		+= scripts/Makefile.kcov
1111include-$(CONFIG_RANDSTRUCT)	+= scripts/Makefile.randstruct
1112include-$(CONFIG_KSTACK_ERASE)	+= scripts/Makefile.kstack_erase
1113include-$(CONFIG_AUTOFDO_CLANG)	+= scripts/Makefile.autofdo
1114include-$(CONFIG_PROPELLER_CLANG)	+= scripts/Makefile.propeller
1115include-$(CONFIG_GCC_PLUGINS)	+= scripts/Makefile.gcc-plugins
1116
1117include $(addprefix $(srctree)/, $(include-y))
1118
1119# scripts/Makefile.gcc-plugins is intentionally included last.
1120# Do not add $(call cc-option,...) below this line. When you build the kernel
1121# from the clean source tree, the GCC plugins do not exist at this point.
1122
1123# Add user supplied CPPFLAGS, AFLAGS, CFLAGS and RUSTFLAGS as the last assignments
1124KBUILD_CPPFLAGS += $(KCPPFLAGS)
1125KBUILD_AFLAGS   += $(KAFLAGS)
1126KBUILD_CFLAGS   += $(KCFLAGS)
1127KBUILD_RUSTFLAGS += $(KRUSTFLAGS)
1128
1129KBUILD_LDFLAGS_MODULE += --build-id=sha1
1130LDFLAGS_vmlinux += --build-id=sha1
1131
1132KBUILD_LDFLAGS	+= -z noexecstack
1133ifeq ($(CONFIG_LD_IS_BFD),y)
1134KBUILD_LDFLAGS	+= $(call ld-option,--no-warn-rwx-segments)
1135endif
1136
1137ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1138LDFLAGS_vmlinux	+= -X
1139endif
1140
1141ifeq ($(CONFIG_RELR),y)
1142# ld.lld before 15 did not support -z pack-relative-relocs.
1143LDFLAGS_vmlinux	+= $(call ld-option,--pack-dyn-relocs=relr,-z pack-relative-relocs)
1144endif
1145
1146# We never want expected sections to be placed heuristically by the
1147# linker. All sections should be explicitly named in the linker script.
1148ifdef CONFIG_LD_ORPHAN_WARN
1149LDFLAGS_vmlinux += --orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL)
1150endif
1151
1152ifneq ($(CONFIG_ARCH_VMLINUX_NEEDS_RELOCS),)
1153LDFLAGS_vmlinux	+= --emit-relocs --discard-none
1154endif
1155
1156# Align the bit size of userspace programs with the kernel
1157USERFLAGS_FROM_KERNEL := -m32 -m64 --target=%
1158KBUILD_USERCFLAGS  += $(filter $(USERFLAGS_FROM_KERNEL), $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS))
1159KBUILD_USERLDFLAGS += $(filter $(USERFLAGS_FROM_KERNEL), $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS))
1160
1161# userspace programs are linked via the compiler, use the correct linker
1162ifdef CONFIG_CC_IS_CLANG
1163KBUILD_USERLDFLAGS += --ld-path=$(LD)
1164endif
1165
1166# make the checker run with the right architecture
1167CHECKFLAGS += --arch=$(ARCH)
1168
1169# insure the checker run with the right endianness
1170CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1171
1172# the checker needs the correct machine size
1173CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1174
1175# Default kernel image to build when no specific target is given.
1176# KBUILD_IMAGE may be overruled on the command line or
1177# set in the environment
1178# Also any assignments in arch/$(ARCH)/Makefile take precedence over
1179# this default value
1180export KBUILD_IMAGE ?= vmlinux
1181
1182#
1183# INSTALL_PATH specifies where to place the updated kernel and system map
1184# images. Default is /boot, but you can set it to other values
1185export	INSTALL_PATH ?= /boot
1186
1187#
1188# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1189# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1190# an argument if needed. Otherwise it defaults to the kernel install path
1191#
1192export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1193
1194#
1195# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1196# relocations required by build roots.  This is not defined in the
1197# makefile but the argument can be passed to make if needed.
1198#
1199
1200MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1201export MODLIB
1202
1203PHONY += prepare0
1204
1205ifeq ($(KBUILD_EXTMOD),)
1206
1207build-dir	:= .
1208clean-dirs	:= $(sort . Documentation \
1209		     $(patsubst %/,%,$(filter %/, $(core-) \
1210			$(drivers-) $(libs-))))
1211
1212export ARCH_CORE	:= $(core-y)
1213export ARCH_LIB		:= $(filter %/, $(libs-y))
1214export ARCH_DRIVERS	:= $(drivers-y) $(drivers-m)
1215# Externally visible symbols (used by link-vmlinux.sh)
1216
1217KBUILD_VMLINUX_OBJS := built-in.a $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1218KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1219
1220export KBUILD_VMLINUX_LIBS
1221export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1222
1223ifdef CONFIG_TRIM_UNUSED_KSYMS
1224# For the kernel to actually contain only the needed exported symbols,
1225# we have to build modules as well to determine what those symbols are.
1226KBUILD_MODULES := y
1227endif
1228
1229# '$(AR) mPi' needs 'T' to workaround the bug of llvm-ar <= 14
1230quiet_cmd_ar_vmlinux.a = AR      $@
1231      cmd_ar_vmlinux.a = \
1232	rm -f $@; \
1233	$(AR) cDPrST $@ $(KBUILD_VMLINUX_OBJS); \
1234	$(AR) mPiT $$($(AR) t $@ | sed -n 1p) $@ $$($(AR) t $@ | grep -F -f $(srctree)/scripts/head-object-list.txt)
1235
1236targets += vmlinux.a
1237vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt FORCE
1238	$(call if_changed,ar_vmlinux.a)
1239
1240PHONY += vmlinux_o
1241vmlinux_o: vmlinux.a $(KBUILD_VMLINUX_LIBS)
1242	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o
1243
1244vmlinux.o modules.builtin.modinfo modules.builtin: vmlinux_o
1245	@:
1246
1247PHONY += vmlinux
1248# LDFLAGS_vmlinux in the top Makefile defines linker flags for the top vmlinux,
1249# not for decompressors. LDFLAGS_vmlinux in arch/*/boot/compressed/Makefile is
1250# unrelated; the decompressors just happen to have the same base name,
1251# arch/*/boot/compressed/vmlinux.
1252# Export LDFLAGS_vmlinux only to scripts/Makefile.vmlinux.
1253#
1254# _LDFLAGS_vmlinux is a workaround for the 'private export' bug:
1255#   https://savannah.gnu.org/bugs/?61463
1256# For Make > 4.4, the following simple code will work:
1257#  vmlinux: private export LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1258vmlinux: private _LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1259vmlinux: export LDFLAGS_vmlinux = $(_LDFLAGS_vmlinux)
1260vmlinux: vmlinux.o $(KBUILD_LDS) modpost
1261	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux
1262
1263# The actual objects are generated when descending,
1264# make sure no implicit rule kicks in
1265$(sort $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)): . ;
1266
1267ifeq ($(origin KERNELRELEASE),file)
1268filechk_kernel.release = $(srctree)/scripts/setlocalversion $(srctree)
1269else
1270filechk_kernel.release = echo $(KERNELRELEASE)
1271endif
1272
1273# Store (new) KERNELRELEASE string in include/config/kernel.release
1274include/config/kernel.release: FORCE
1275	$(call filechk,kernel.release)
1276
1277# Additional helpers built in scripts/
1278# Carefully list dependencies so we do not try to build scripts twice
1279# in parallel
1280PHONY += scripts
1281scripts: scripts_basic scripts_dtc
1282	$(Q)$(MAKE) $(build)=$(@)
1283
1284# Things we need to do before we recursively start building the kernel
1285# or the modules are listed in "prepare".
1286# A multi level approach is used. prepareN is processed before prepareN-1.
1287# archprepare is used in arch Makefiles and when processed asm symlink,
1288# version.h and scripts_basic is processed / created.
1289
1290PHONY += prepare archprepare
1291
1292archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1293	asm-generic $(version_h) include/generated/utsrelease.h \
1294	include/generated/compile.h include/generated/autoconf.h \
1295	include/generated/rustc_cfg remove-stale-files
1296
1297prepare0: archprepare
1298	$(Q)$(MAKE) $(build)=scripts/mod
1299	$(Q)$(MAKE) $(build)=. prepare
1300
1301# All the preparing..
1302prepare: prepare0
1303ifdef CONFIG_RUST
1304	+$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh
1305	$(Q)$(MAKE) $(build)=rust
1306endif
1307
1308PHONY += remove-stale-files
1309remove-stale-files:
1310	$(Q)$(srctree)/scripts/remove-stale-files
1311
1312# Support for using generic headers in asm-generic
1313asm-generic := -f $(srctree)/scripts/Makefile.asm-headers obj
1314
1315PHONY += asm-generic uapi-asm-generic
1316asm-generic: uapi-asm-generic
1317	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1318	generic=include/asm-generic
1319uapi-asm-generic:
1320	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1321	generic=include/uapi/asm-generic
1322
1323# Generate some files
1324# ---------------------------------------------------------------------------
1325
1326# KERNELRELEASE can change from a few different places, meaning version.h
1327# needs to be updated, so this check is forced on all builds
1328
1329uts_len := 64
1330define filechk_utsrelease.h
1331	if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1332	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1333	  exit 1;                                                         \
1334	fi;                                                               \
1335	echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1336endef
1337
1338define filechk_version.h
1339	if [ $(SUBLEVEL) -gt 255 ]; then                                 \
1340		echo \#define LINUX_VERSION_CODE $(shell                 \
1341		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1342	else                                                             \
1343		echo \#define LINUX_VERSION_CODE $(shell                 \
1344		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1345	fi;                                                              \
1346	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
1347	((c) > 255 ? 255 : (c)))';                                       \
1348	echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
1349	echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
1350	echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1351endef
1352
1353$(version_h): private PATCHLEVEL := $(or $(PATCHLEVEL), 0)
1354$(version_h): private SUBLEVEL := $(or $(SUBLEVEL), 0)
1355$(version_h): FORCE
1356	$(call filechk,version.h)
1357
1358include/generated/utsrelease.h: include/config/kernel.release FORCE
1359	$(call filechk,utsrelease.h)
1360
1361filechk_compile.h = $(srctree)/scripts/mkcompile_h \
1362	"$(UTS_MACHINE)" "$(CONFIG_CC_VERSION_TEXT)" "$(LD)"
1363
1364include/generated/compile.h: FORCE
1365	$(call filechk,compile.h)
1366
1367PHONY += headerdep
1368headerdep:
1369	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1370	$(srctree)/scripts/headerdep.pl -I$(srctree)/include
1371
1372# ---------------------------------------------------------------------------
1373# Kernel headers
1374
1375#Default location for installed headers
1376export INSTALL_HDR_PATH = $(objtree)/usr
1377
1378quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1379      cmd_headers_install = \
1380	mkdir -p $(INSTALL_HDR_PATH); \
1381	rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1382	usr/include $(INSTALL_HDR_PATH)
1383
1384PHONY += headers_install
1385headers_install: headers
1386	$(call cmd,headers_install)
1387
1388PHONY += archheaders archscripts
1389
1390hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1391
1392PHONY += headers
1393headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders
1394ifdef HEADER_ARCH
1395	$(Q)$(MAKE) -f $(srctree)/Makefile HEADER_ARCH= SRCARCH=$(HEADER_ARCH) headers
1396else
1397	$(Q)$(MAKE) $(hdr-inst)=include/uapi
1398	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1399endif
1400
1401ifdef CONFIG_HEADERS_INSTALL
1402prepare: headers
1403endif
1404
1405PHONY += scripts_unifdef
1406scripts_unifdef: scripts_basic
1407	$(Q)$(MAKE) $(build)=scripts scripts/unifdef
1408
1409PHONY += scripts_gen_packed_field_checks
1410scripts_gen_packed_field_checks: scripts_basic
1411	$(Q)$(MAKE) $(build)=scripts scripts/gen_packed_field_checks
1412
1413# ---------------------------------------------------------------------------
1414# Install
1415
1416# Many distributions have the custom install script, /sbin/installkernel.
1417# If DKMS is installed, 'make install' will eventually recurse back
1418# to this Makefile to build and install external modules.
1419# Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
1420
1421quiet_cmd_install = INSTALL $(INSTALL_PATH)
1422      cmd_install = unset sub_make_done; $(srctree)/scripts/install.sh
1423
1424# ---------------------------------------------------------------------------
1425# vDSO install
1426
1427PHONY += vdso_install
1428vdso_install: export INSTALL_FILES = $(vdso-install-y)
1429vdso_install:
1430	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vdsoinst
1431
1432# ---------------------------------------------------------------------------
1433# Tools
1434
1435ifdef CONFIG_OBJTOOL
1436prepare: tools/objtool
1437endif
1438
1439ifdef CONFIG_BPF
1440ifdef CONFIG_DEBUG_INFO_BTF
1441prepare: tools/bpf/resolve_btfids
1442endif
1443endif
1444
1445# The tools build system is not a part of Kbuild and tends to introduce
1446# its own unique issues. If you need to integrate a new tool into Kbuild,
1447# please consider locating that tool outside the tools/ tree and using the
1448# standard Kbuild "hostprogs" syntax instead of adding a new tools/* entry
1449# here. See Documentation/kbuild/makefiles.rst for details.
1450
1451PHONY += resolve_btfids_clean
1452
1453resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1454
1455# tools/bpf/resolve_btfids directory might not exist
1456# in output directory, skip its clean in that case
1457resolve_btfids_clean:
1458ifneq ($(wildcard $(resolve_btfids_O)),)
1459	$(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1460endif
1461
1462tools/: FORCE
1463	$(Q)mkdir -p $(objtree)/tools
1464	$(Q)$(MAKE) O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1465
1466tools/%: FORCE
1467	$(Q)mkdir -p $(objtree)/tools
1468	$(Q)$(MAKE) O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1469
1470# ---------------------------------------------------------------------------
1471# Kernel selftest
1472
1473PHONY += kselftest
1474kselftest: headers
1475	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1476
1477kselftest-%: headers FORCE
1478	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1479
1480PHONY += kselftest-merge
1481kselftest-merge:
1482	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1483	$(Q)find $(srctree)/tools/testing/selftests -name config -o -name config.$(UTS_MACHINE) | \
1484		xargs $(srctree)/scripts/kconfig/merge_config.sh -y -m $(objtree)/.config
1485	$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1486
1487# ---------------------------------------------------------------------------
1488# Devicetree files
1489
1490ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1491dtstree := arch/$(SRCARCH)/boot/dts
1492endif
1493
1494ifneq ($(dtstree),)
1495
1496%.dtb: dtbs_prepare
1497	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1498
1499%.dtbo: dtbs_prepare
1500	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1501
1502PHONY += dtbs dtbs_prepare dtbs_install dtbs_check
1503dtbs: dtbs_prepare
1504	$(Q)$(MAKE) $(build)=$(dtstree) need-dtbslist=1
1505
1506# include/config/kernel.release is actually needed when installing DTBs because
1507# INSTALL_DTBS_PATH contains $(KERNELRELEASE). However, we do not want to make
1508# dtbs_install depend on it as dtbs_install may run as root.
1509dtbs_prepare: include/config/kernel.release scripts_dtc
1510
1511ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1512export CHECK_DTBS=y
1513endif
1514
1515ifneq ($(CHECK_DTBS),)
1516dtbs_prepare: dt_binding_schemas
1517endif
1518
1519dtbs_check: dtbs
1520
1521dtbs_install:
1522	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.dtbinst obj=$(dtstree)
1523
1524ifdef CONFIG_OF_EARLY_FLATTREE
1525all: dtbs
1526endif
1527
1528ifdef CONFIG_GENERIC_BUILTIN_DTB
1529vmlinux: dtbs
1530endif
1531
1532endif
1533
1534PHONY += scripts_dtc
1535scripts_dtc: scripts_basic
1536	$(Q)$(MAKE) $(build)=scripts/dtc
1537
1538ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1539export CHECK_DTBS=y
1540endif
1541
1542PHONY += dt_binding_check dt_binding_schemas
1543dt_binding_check: dt_binding_schemas scripts_dtc
1544	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1545
1546dt_binding_schemas:
1547	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1548
1549PHONY += dt_compatible_check
1550dt_compatible_check: dt_binding_schemas
1551	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1552
1553# ---------------------------------------------------------------------------
1554# Modules
1555
1556ifdef CONFIG_MODULES
1557
1558# By default, build modules as well
1559
1560all: modules
1561
1562# When we're building modules with modversions, we need to consider
1563# the built-in objects during the descend as well, in order to
1564# make sure the checksums are up to date before we record them.
1565ifdef CONFIG_MODVERSIONS
1566  KBUILD_BUILTIN := y
1567endif
1568
1569# Build modules
1570#
1571
1572# *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFO_BTF_MODULES
1573# is an exception.
1574ifdef CONFIG_DEBUG_INFO_BTF_MODULES
1575KBUILD_BUILTIN := y
1576modules: vmlinux
1577endif
1578
1579modules: modules_prepare
1580
1581# Target to prepare building external modules
1582modules_prepare: prepare
1583	$(Q)$(MAKE) $(build)=scripts scripts/module.lds
1584
1585endif # CONFIG_MODULES
1586
1587###
1588# Cleaning is done on three levels.
1589# make clean     Delete most generated files
1590#                Leave enough to build external modules
1591# make mrproper  Delete the current configuration, and all generated files
1592# make distclean Remove editor backup files, patch leftover files and the like
1593
1594# Directories & files removed with 'make clean'
1595CLEAN_FILES += vmlinux.symvers modules-only.symvers \
1596	       modules.builtin modules.builtin.modinfo modules.nsdeps \
1597	       modules.builtin.ranges vmlinux.o.map vmlinux.unstripped \
1598	       compile_commands.json rust/test \
1599	       rust-project.json .vmlinux.objs .vmlinux.export.c \
1600               .builtin-dtbs-list .builtin-dtb.S
1601
1602# Directories & files removed with 'make mrproper'
1603MRPROPER_FILES += include/config include/generated          \
1604		  arch/$(SRCARCH)/include/generated .objdiff \
1605		  debian snap tar-install PKGBUILD pacman \
1606		  .config .config.old .version \
1607		  Module.symvers \
1608		  certs/signing_key.pem \
1609		  certs/x509.genkey \
1610		  vmlinux-gdb.py \
1611		  rpmbuild \
1612		  rust/libmacros.so rust/libmacros.dylib
1613
1614# clean - Delete most, but leave enough to build external modules
1615#
1616clean: private rm-files := $(CLEAN_FILES)
1617
1618PHONY += archclean vmlinuxclean
1619
1620vmlinuxclean:
1621	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1622	$(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1623
1624clean: archclean vmlinuxclean resolve_btfids_clean
1625
1626# mrproper - Delete all generated files, including .config
1627#
1628mrproper: private rm-files := $(MRPROPER_FILES)
1629mrproper-dirs      := $(addprefix _mrproper_,scripts)
1630
1631PHONY += $(mrproper-dirs) mrproper
1632$(mrproper-dirs):
1633	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1634
1635mrproper: clean $(mrproper-dirs)
1636	$(call cmd,rmfiles)
1637	@find . $(RCS_FIND_IGNORE) \
1638		\( -name '*.rmeta' \) \
1639		-type f -print | xargs rm -f
1640
1641# distclean
1642#
1643PHONY += distclean
1644
1645distclean: mrproper
1646	@find . $(RCS_FIND_IGNORE) \
1647		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1648		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
1649		-o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1650		-o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1651		-type f -print | xargs rm -f
1652
1653
1654# Packaging of the kernel to various formats
1655# ---------------------------------------------------------------------------
1656
1657%src-pkg: FORCE
1658	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1659%pkg: include/config/kernel.release FORCE
1660	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1661
1662# Brief documentation of the typical targets used
1663# ---------------------------------------------------------------------------
1664
1665boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1666boards := $(sort $(notdir $(boards)))
1667board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1668board-dirs := $(sort $(notdir $(board-dirs:/=)))
1669
1670PHONY += help
1671help:
1672	@echo  'Cleaning targets:'
1673	@echo  '  clean		  - Remove most generated files but keep the config and'
1674	@echo  '                    enough build support to build external modules'
1675	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
1676	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
1677	@echo  ''
1678	@$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1679	@echo  ''
1680	@echo  'Other generic targets:'
1681	@echo  '  all		  - Build all targets marked with [*]'
1682	@echo  '* vmlinux	  - Build the bare kernel'
1683	@echo  '* modules	  - Build all modules'
1684	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1685	@echo  '  vdso_install    - Install unstripped vdso to INSTALL_MOD_PATH (default: /)'
1686	@echo  '  dir/            - Build all files in dir and below'
1687	@echo  '  dir/file.[ois]  - Build specified target only'
1688	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1689	@echo  '                    (requires compiler support for LLVM assembly generation)'
1690	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1691	@echo  '                    (requires a recent binutils and recent build (System.map))'
1692	@echo  '  dir/file.ko     - Build module including final link'
1693	@echo  '  modules_prepare - Set up for building external modules'
1694	@echo  '  tags/TAGS	  - Generate tags file for editors'
1695	@echo  '  cscope	  - Generate cscope index'
1696	@echo  '  gtags           - Generate GNU GLOBAL index'
1697	@echo  '  kernelrelease	  - Output the release version string (use with make -s)'
1698	@echo  '  kernelversion	  - Output the version stored in Makefile (use with make -s)'
1699	@echo  '  image_name	  - Output the image name (use with make -s)'
1700	@echo  '  headers	  - Build ready-to-install UAPI headers in usr/include'
1701	@echo  '  headers_install - Install sanitised kernel UAPI headers to INSTALL_HDR_PATH'; \
1702	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1703	 echo  ''
1704	@echo  'Static analysers:'
1705	@echo  '  checkstack      - Generate a list of stack hogs and consider all functions'
1706	@echo  '                    with a stack size larger than MINSTACKSIZE (default: 100)'
1707	@echo  '  versioncheck    - Sanity check on version.h usage'
1708	@echo  '  includecheck    - Check for duplicate included header files'
1709	@echo  '  headerdep       - Detect inclusion cycles in headers'
1710	@echo  '  coccicheck      - Check with Coccinelle'
1711	@echo  '  clang-analyzer  - Check with clang static analyzer'
1712	@echo  '  clang-tidy      - Check with clang-tidy'
1713	@echo  ''
1714	@echo  'Tools:'
1715	@echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1716	@echo  ''
1717	@echo  'Kernel selftest:'
1718	@echo  '  kselftest         - Build and run kernel selftest'
1719	@echo  '                      Build, install, and boot kernel before'
1720	@echo  '                      running kselftest on it'
1721	@echo  '                      Run as root for full coverage'
1722	@echo  '  kselftest-all     - Build kernel selftest'
1723	@echo  '  kselftest-install - Build and install kernel selftest'
1724	@echo  '  kselftest-clean   - Remove all generated kselftest files'
1725	@echo  '  kselftest-merge   - Merge all the config dependencies of'
1726	@echo  '		      kselftest to existing .config.'
1727	@echo  ''
1728	@echo  'Rust targets:'
1729	@echo  '  rustavailable   - Checks whether the Rust toolchain is'
1730	@echo  '		    available and, if not, explains why.'
1731	@echo  '  rustfmt	  - Reformat all the Rust code in the kernel'
1732	@echo  '  rustfmtcheck	  - Checks if all the Rust code in the kernel'
1733	@echo  '		    is formatted, printing a diff otherwise.'
1734	@echo  '  rustdoc	  - Generate Rust documentation'
1735	@echo  '		    (requires kernel .config)'
1736	@echo  '  rusttest        - Runs the Rust tests'
1737	@echo  '                    (requires kernel .config; downloads external repos)'
1738	@echo  '  rust-analyzer	  - Generate rust-project.json rust-analyzer support file'
1739	@echo  '		    (requires kernel .config)'
1740	@echo  '  dir/file.[os]   - Build specified target only'
1741	@echo  '  dir/file.rsi    - Build macro expanded source, similar to C preprocessing.'
1742	@echo  '                    Run with RUSTFMT=n to skip reformatting if needed.'
1743	@echo  '                    The output is not intended to be compilable.'
1744	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1745	@echo  ''
1746	@$(if $(dtstree), \
1747		echo 'Devicetree:'; \
1748		echo '* dtbs               - Build device tree blobs for enabled boards'; \
1749		echo '  dtbs_install       - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1750		echo '  dt_binding_check   - Validate device tree binding documents and examples'; \
1751		echo '  dt_binding_schemas - Build processed device tree binding schemas'; \
1752		echo '  dtbs_check         - Validate device tree source files';\
1753		echo '')
1754
1755	@echo 'Userspace tools targets:'
1756	@echo '  use "make tools/help"'
1757	@echo '  or  "cd tools; make help"'
1758	@echo  ''
1759	@echo  'Kernel packaging:'
1760	@$(MAKE) -f $(srctree)/scripts/Makefile.package help
1761	@echo  ''
1762	@echo  'Documentation targets:'
1763	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1764	@echo  ''
1765	@echo  'Architecture-specific targets ($(SRCARCH)):'
1766	@$(or $(archhelp),\
1767		echo '  No architecture-specific help defined for $(SRCARCH)')
1768	@echo  ''
1769	@$(if $(boards), \
1770		$(foreach b, $(boards), \
1771		printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1772		echo '')
1773	@$(if $(board-dirs), \
1774		$(foreach b, $(board-dirs), \
1775		printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1776		printf "  %-16s - Show all of the above\\n" help-boards; \
1777		echo '')
1778
1779	@echo  '  make V=n   [targets] 1: verbose build'
1780	@echo  '                       2: give reason for rebuild of target'
1781	@echo  '                       V=1 and V=2 can be combined with V=12'
1782	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1783	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1784	@echo  '                       (sparse by default)'
1785	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1786	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1787	@echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3,c,e where'
1788	@echo  '		1: warnings which may be relevant and do not occur too often'
1789	@echo  '		2: warnings which occur quite often but may still be relevant'
1790	@echo  '		3: more obscure warnings, can most likely be ignored'
1791	@echo  '		c: extra checks in the configuration stage (Kconfig)'
1792	@echo  '		e: warnings are being treated as errors'
1793	@echo  '		Multiple levels can be combined with W=12 or W=123'
1794	@echo  '  make UT=1   [targets] Warn if a tracepoint is defined but not used.'
1795	@echo  '          [ This will be removed when all current unused tracepoints are eliminated. ]'
1796	@$(if $(dtstree), \
1797		echo '  make CHECK_DTBS=1 [targets] Check all generated dtb files against schema'; \
1798		echo '         This can be applied both to "dtbs" and to individual "foo.dtb" targets' ; \
1799		)
1800	@echo  ''
1801	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
1802	@echo  'For further info see the ./README file'
1803
1804
1805help-board-dirs := $(addprefix help-,$(board-dirs))
1806
1807help-boards: $(help-board-dirs)
1808
1809boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1810
1811$(help-board-dirs): help-%:
1812	@echo  'Architecture-specific targets ($(SRCARCH) $*):'
1813	@$(if $(boards-per-dir), \
1814		$(foreach b, $(boards-per-dir), \
1815		printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1816		echo '')
1817
1818
1819# Documentation targets
1820# ---------------------------------------------------------------------------
1821DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs htmldocs-redirects \
1822	       epubdocs cleandocs linkcheckdocs dochelp refcheckdocs \
1823	       texinfodocs infodocs
1824PHONY += $(DOC_TARGETS)
1825$(DOC_TARGETS):
1826	$(Q)$(MAKE) $(build)=Documentation $@
1827
1828
1829# Rust targets
1830# ---------------------------------------------------------------------------
1831
1832# "Is Rust available?" target
1833PHONY += rustavailable
1834rustavailable:
1835	+$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh && echo "Rust is available!"
1836
1837# Documentation target
1838#
1839# Using the singular to avoid running afoul of `no-dot-config-targets`.
1840PHONY += rustdoc
1841rustdoc: prepare
1842	$(Q)$(MAKE) $(build)=rust $@
1843
1844# Testing target
1845PHONY += rusttest
1846rusttest: prepare
1847	$(Q)$(MAKE) $(build)=rust $@
1848
1849# Formatting targets
1850PHONY += rustfmt rustfmtcheck
1851
1852rustfmt:
1853	$(Q)find $(srctree) $(RCS_FIND_IGNORE) \
1854		-type f -a -name '*.rs' -a ! -name '*generated*' -print \
1855		| xargs $(RUSTFMT) $(rustfmt_flags)
1856
1857rustfmtcheck: rustfmt_flags = --check
1858rustfmtcheck: rustfmt
1859
1860# Misc
1861# ---------------------------------------------------------------------------
1862
1863PHONY += misc-check
1864misc-check:
1865	$(Q)$(srctree)/scripts/misc-check
1866
1867all: misc-check
1868
1869PHONY += scripts_gdb
1870scripts_gdb: prepare0
1871	$(Q)$(MAKE) $(build)=scripts/gdb
1872	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1873
1874ifdef CONFIG_GDB_SCRIPTS
1875all: scripts_gdb
1876endif
1877
1878else # KBUILD_EXTMOD
1879
1880filechk_kernel.release = echo $(KERNELRELEASE)
1881
1882###
1883# External module support.
1884# When building external modules the kernel used as basis is considered
1885# read-only, and no consistency checks are made and the make
1886# system is not used on the basis kernel. If updates are required
1887# in the basis kernel ordinary make commands (without M=...) must be used.
1888
1889# We are always building only modules.
1890KBUILD_BUILTIN :=
1891KBUILD_MODULES := y
1892
1893build-dir := .
1894
1895clean-dirs := .
1896clean: private rm-files := Module.symvers modules.nsdeps compile_commands.json
1897
1898PHONY += prepare
1899# now expand this into a simple variable to reduce the cost of shell evaluations
1900prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT)
1901prepare:
1902	@if [ "$(CC_VERSION_TEXT)" != "$(CONFIG_CC_VERSION_TEXT)" ]; then \
1903		echo >&2 "warning: the compiler differs from the one used to build the kernel"; \
1904		echo >&2 "  The kernel was built by: $(CONFIG_CC_VERSION_TEXT)"; \
1905		echo >&2 "  You are using:           $(CC_VERSION_TEXT)"; \
1906	fi
1907
1908PHONY += help
1909help:
1910	@echo  '  Building external modules.'
1911	@echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1912	@echo  ''
1913	@echo  '  modules         - default target, build the module(s)'
1914	@echo  '  modules_install - install the module'
1915	@echo  '  clean           - remove generated files in module directory only'
1916	@echo  '  rust-analyzer	  - generate rust-project.json rust-analyzer support file'
1917	@echo  ''
1918
1919ifndef CONFIG_MODULES
1920modules modules_install: __external_modules_error
1921__external_modules_error:
1922	@echo >&2 '***'
1923	@echo >&2 '*** The present kernel disabled CONFIG_MODULES.'
1924	@echo >&2 '*** You cannot build or install external modules.'
1925	@echo >&2 '***'
1926	@false
1927endif
1928
1929endif # KBUILD_EXTMOD
1930
1931# ---------------------------------------------------------------------------
1932# Modules
1933
1934PHONY += modules modules_install modules_sign modules_prepare
1935
1936modules_install:
1937	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst \
1938	sign-only=$(if $(filter modules_install,$(MAKECMDGOALS)),,y)
1939
1940ifeq ($(CONFIG_MODULE_SIG),y)
1941# modules_sign is a subset of modules_install.
1942# 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1943modules_sign: modules_install
1944	@:
1945else
1946modules_sign:
1947	@echo >&2 '***'
1948	@echo >&2 '*** CONFIG_MODULE_SIG is disabled. You cannot sign modules.'
1949	@echo >&2 '***'
1950	@false
1951endif
1952
1953ifdef CONFIG_MODULES
1954
1955modules.order: $(build-dir)
1956	@:
1957
1958# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
1959# This is solely useful to speed up test compiles.
1960modules: modpost
1961ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1962	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1963endif
1964
1965PHONY += modules_check
1966modules_check: modules.order
1967	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1968
1969else # CONFIG_MODULES
1970
1971modules:
1972	@:
1973
1974KBUILD_MODULES :=
1975
1976endif # CONFIG_MODULES
1977
1978PHONY += modpost
1979modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \
1980	 $(if $(KBUILD_MODULES), modules_check)
1981	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1982
1983# Single targets
1984# ---------------------------------------------------------------------------
1985# To build individual files in subdirectories, you can do like this:
1986#
1987#   make foo/bar/baz.s
1988#
1989# The supported suffixes for single-target are listed in 'single-targets'
1990#
1991# To build only under specific subdirectories, you can do like this:
1992#
1993#   make foo/bar/baz/
1994
1995ifdef single-build
1996
1997# .ko is special because modpost is needed
1998single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1999single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \
2000		$(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko)))
2001
2002$(single-ko): single_modules
2003	@:
2004$(single-no-ko): $(build-dir)
2005	@:
2006
2007# Remove modules.order when done because it is not the real one.
2008PHONY += single_modules
2009single_modules: $(single-no-ko) modules_prepare
2010	$(Q){ $(foreach m, $(single-ko), echo $(m:%.ko=%.o);) } > modules.order
2011	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
2012ifneq ($(KBUILD_MODPOST_NOFINAL),1)
2013	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
2014endif
2015	$(Q)rm -f modules.order
2016
2017single-goals := $(addprefix $(build-dir)/, $(single-no-ko))
2018
2019KBUILD_MODULES := y
2020
2021endif
2022
2023prepare: outputmakefile
2024
2025# Preset locale variables to speed up the build process. Limit locale
2026# tweaks to this spot to avoid wrong language settings when running
2027# make menuconfig etc.
2028# Error messages still appears in the original language
2029PHONY += $(build-dir)
2030$(build-dir): prepare
2031	$(Q)$(MAKE) $(build)=$@ need-builtin=1 need-modorder=1 $(single-goals)
2032
2033clean-dirs := $(addprefix _clean_, $(clean-dirs))
2034PHONY += $(clean-dirs) clean
2035$(clean-dirs):
2036	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
2037
2038clean: $(clean-dirs)
2039	$(call cmd,rmfiles)
2040	@find . $(RCS_FIND_IGNORE) \
2041		\( -name '*.[aios]' -o -name '*.rsi' -o -name '*.ko' -o -name '.*.cmd' \
2042		-o -name '*.ko.*' \
2043		-o -name '*.dtb' -o -name '*.dtbo' \
2044		-o -name '*.dtb.S' -o -name '*.dtbo.S' \
2045		-o -name '*.dt.yaml' -o -name 'dtbs-list' \
2046		-o -name '*.dwo' -o -name '*.lst' \
2047		-o -name '*.su' -o -name '*.mod' \
2048		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
2049		-o -name '*.lex.c' -o -name '*.tab.[ch]' \
2050		-o -name '*.asn1.[ch]' \
2051		-o -name '*.symtypes' -o -name 'modules.order' \
2052		-o -name '*.c.[012]*.*' \
2053		-o -name '*.ll' \
2054		-o -name '*.gcno' \
2055		\) -type f -print \
2056		-o -name '.tmp_*' -print \
2057		| xargs rm -rf
2058
2059# Generate tags for editors
2060# ---------------------------------------------------------------------------
2061quiet_cmd_tags = GEN     $@
2062      cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
2063
2064tags TAGS cscope gtags: FORCE
2065	$(call cmd,tags)
2066
2067# Generate rust-project.json (a file that describes the structure of non-Cargo
2068# Rust projects) for rust-analyzer (an implementation of the Language Server
2069# Protocol).
2070PHONY += rust-analyzer
2071rust-analyzer:
2072	+$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh
2073ifdef KBUILD_EXTMOD
2074# FIXME: external modules must not descend into a sub-directory of the kernel
2075	$(Q)$(MAKE) $(build)=$(objtree)/rust src=$(srctree)/rust $@
2076else
2077	$(Q)$(MAKE) $(build)=rust $@
2078endif
2079
2080# Script to generate missing namespace dependencies
2081# ---------------------------------------------------------------------------
2082
2083PHONY += nsdeps
2084nsdeps: export KBUILD_NSDEPS=1
2085nsdeps: modules
2086	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
2087
2088# Clang Tooling
2089# ---------------------------------------------------------------------------
2090
2091quiet_cmd_gen_compile_commands = GEN     $@
2092      cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
2093
2094compile_commands.json: $(srctree)/scripts/clang-tools/gen_compile_commands.py \
2095	$(if $(KBUILD_EXTMOD),, vmlinux.a $(KBUILD_VMLINUX_LIBS)) \
2096	$(if $(CONFIG_MODULES), modules.order) FORCE
2097	$(call if_changed,gen_compile_commands)
2098
2099targets += compile_commands.json
2100
2101PHONY += clang-tidy clang-analyzer
2102
2103ifdef CONFIG_CC_IS_CLANG
2104quiet_cmd_clang_tools = CHECK   $<
2105      cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
2106
2107clang-tidy clang-analyzer: compile_commands.json
2108	$(call cmd,clang_tools)
2109else
2110clang-tidy clang-analyzer:
2111	@echo "$@ requires CC=clang" >&2
2112	@false
2113endif
2114
2115# Scripts to check various things for consistency
2116# ---------------------------------------------------------------------------
2117
2118PHONY += includecheck versioncheck coccicheck
2119
2120includecheck:
2121	find $(srctree)/* $(RCS_FIND_IGNORE) \
2122		-name '*.[hcS]' -type f -print | sort \
2123		| xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
2124
2125versioncheck:
2126	find $(srctree)/* $(RCS_FIND_IGNORE) \
2127		-name '*.[hcS]' -type f -print | sort \
2128		| xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
2129
2130coccicheck:
2131	$(Q)$(BASH) $(srctree)/scripts/$@
2132
2133PHONY += checkstack kernelrelease kernelversion image_name
2134
2135# UML needs a little special treatment here.  It wants to use the host
2136# toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
2137# else wants $(ARCH), including people doing cross-builds, which means
2138# that $(SUBARCH) doesn't work here.
2139ifeq ($(ARCH), um)
2140CHECKSTACK_ARCH := $(SUBARCH)
2141else
2142CHECKSTACK_ARCH := $(ARCH)
2143endif
2144MINSTACKSIZE	?= 100
2145checkstack:
2146	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
2147	$(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH) $(MINSTACKSIZE)
2148
2149kernelrelease:
2150	@$(filechk_kernel.release)
2151
2152kernelversion:
2153	@echo $(KERNELVERSION)
2154
2155image_name:
2156	@echo $(KBUILD_IMAGE)
2157
2158PHONY += run-command
2159run-command:
2160	$(Q)$(KBUILD_RUN_COMMAND)
2161
2162quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
2163      cmd_rmfiles = rm -rf $(rm-files)
2164
2165# read saved command lines for existing targets
2166existing-targets := $(wildcard $(sort $(targets)))
2167
2168-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
2169
2170endif # config-build
2171endif # mixed-build
2172endif # need-sub-make
2173
2174PHONY += FORCE
2175FORCE:
2176
2177# Declare the contents of the PHONY variable as phony.  We keep that
2178# information in a variable so we can use it in if_changed and friends.
2179.PHONY: $(PHONY)
2180