xref: /linux/Makefile (revision 0bff7711c19ba05ff3b686554c5a2d503c3e9797)
1# SPDX-License-Identifier: GPL-2.0
2VERSION = 7
3PATCHLEVEL = 2
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			 kconfig-sym-check \
297			 $(version_h) headers headers_% archheaders archscripts \
298			 %asm-generic kernelversion %src-pkg dt_binding_check \
299			 dt_style_selftest \
300			 outputmakefile rustavailable rustfmt rustfmtcheck \
301			 run-command
302no-sync-config-targets := $(no-dot-config-targets) %install modules_sign kernelrelease \
303			  image_name
304single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.rsi %.s %/
305
306config-build	:=
307mixed-build	:=
308need-config	:= 1
309may-sync-config	:= 1
310single-build	:=
311
312ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
313    ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
314        need-config :=
315    endif
316endif
317
318ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
319    ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
320        may-sync-config :=
321    endif
322endif
323
324need-compiler := $(may-sync-config)
325
326ifneq ($(KBUILD_EXTMOD),)
327    may-sync-config :=
328endif
329
330ifeq ($(KBUILD_EXTMOD),)
331    ifneq ($(filter %config,$(MAKECMDGOALS)),)
332        config-build := 1
333        ifneq ($(words $(MAKECMDGOALS)),1)
334            mixed-build := 1
335        endif
336    endif
337endif
338
339# We cannot build single targets and the others at the same time
340ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
341    single-build := 1
342    ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
343        mixed-build := 1
344    endif
345endif
346
347# For "make -j clean all", "make -j mrproper defconfig all", etc.
348ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
349    ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
350        mixed-build := 1
351    endif
352endif
353
354# install and modules_install need also be processed one by one
355ifneq ($(filter install,$(MAKECMDGOALS)),)
356    ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
357        mixed-build := 1
358    endif
359endif
360
361ifdef mixed-build
362# ===========================================================================
363# We're called with mixed targets (*config and build targets).
364# Handle them one by one.
365
366PHONY += $(MAKECMDGOALS) __build_one_by_one
367
368$(MAKECMDGOALS): __build_one_by_one
369	@:
370
371__build_one_by_one:
372	$(Q)set -e; \
373	for i in $(MAKECMDGOALS); do \
374		$(MAKE) -f $(srctree)/Makefile $$i; \
375	done
376
377else # !mixed-build
378
379include $(srctree)/scripts/Kbuild.include
380
381# Read KERNELRELEASE from include/config/kernel.release (if it exists)
382KERNELRELEASE = $(call read-file, $(objtree)/include/config/kernel.release)
383KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
384export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
385
386include $(srctree)/scripts/subarch.include
387
388# Cross compiling and selecting different set of gcc/bin-utils
389# ---------------------------------------------------------------------------
390#
391# When performing cross compilation for other architectures ARCH shall be set
392# to the target architecture. (See arch/* for the possibilities).
393# ARCH can be set during invocation of make:
394# make ARCH=arm64
395# Another way is to have ARCH set in the environment.
396# The default ARCH is the host where make is executed.
397
398# CROSS_COMPILE specify the prefix used for all executables used
399# during compilation. Only gcc and related bin-utils executables
400# are prefixed with $(CROSS_COMPILE).
401# CROSS_COMPILE can be set on the command line
402# make CROSS_COMPILE=aarch64-linux-gnu-
403# Alternatively CROSS_COMPILE can be set in the environment.
404# Default value for CROSS_COMPILE is not to prefix executables
405# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
406ARCH		?= $(SUBARCH)
407
408# Architecture as present in compile.h
409UTS_MACHINE 	:= $(ARCH)
410SRCARCH 	:= $(ARCH)
411
412# Additional ARCH settings for x86
413ifeq ($(ARCH),i386)
414        SRCARCH := x86
415endif
416ifeq ($(ARCH),x86_64)
417        SRCARCH := x86
418endif
419
420# Additional ARCH settings for sparc
421ifeq ($(ARCH),sparc32)
422       SRCARCH := sparc
423endif
424ifeq ($(ARCH),sparc64)
425       SRCARCH := sparc
426endif
427
428# Additional ARCH settings for parisc
429ifeq ($(ARCH),parisc64)
430       SRCARCH := parisc
431endif
432
433export cross_compiling :=
434ifneq ($(SRCARCH),$(SUBARCH))
435cross_compiling := 1
436endif
437
438KCONFIG_CONFIG	?= .config
439export KCONFIG_CONFIG
440
441# SHELL used by kbuild
442CONFIG_SHELL := sh
443
444HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
445HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
446HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
447
448ifneq ($(LLVM),)
449ifneq ($(filter %/,$(LLVM)),)
450LLVM_PREFIX := $(LLVM)
451else ifneq ($(filter -%,$(LLVM)),)
452LLVM_SUFFIX := $(LLVM)
453else ifneq ($(LLVM),1)
454$(error Invalid value for LLVM, see Documentation/kbuild/llvm.rst)
455endif
456
457HOSTCC	= $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
458HOSTCXX	= $(LLVM_PREFIX)clang++$(LLVM_SUFFIX)
459else
460HOSTCC	= gcc
461HOSTCXX	= g++
462endif
463HOSTRUSTC = rustc
464HOSTPKG_CONFIG	= pkg-config
465
466# the KERNELDOC macro needs to be exported, as scripts/Makefile.build
467# has a logic to call it
468KERNELDOC       = $(srctree)/tools/docs/kernel-doc
469export KERNELDOC
470
471KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
472			 -O2 -fomit-frame-pointer -std=gnu11
473KBUILD_USERCFLAGS  := $(KBUILD_USERHOSTCFLAGS) $(USERCFLAGS)
474KBUILD_USERLDFLAGS := $(USERLDFLAGS)
475
476# These flags apply to all Rust code in the tree, including the kernel and
477# host programs.
478#
479# `-Aclippy::unwrap_or_default`: the lint is buggy [1] and ignores our
480# MSRV. It can trigger depending on the optimization level.
481# [1] https://github.com/rust-lang/rust-clippy/issues/17379
482export rust_common_flags := --edition=2021 \
483			    -Zbinary_dep_depinfo=y \
484			    -Astable_features \
485			    -Aunused_features \
486			    -Dnon_ascii_idents \
487			    -Dunsafe_op_in_unsafe_fn \
488			    -Wmissing_docs \
489			    -Wrust_2018_idioms \
490			    -Wunreachable_pub \
491			    -Wclippy::all \
492			    -Wclippy::as_ptr_cast_mut \
493			    -Wclippy::as_underscore \
494			    -Wclippy::cast_lossless \
495			    -Aclippy::collapsible_if \
496			    -Aclippy::collapsible_match \
497			    -Wclippy::ignored_unit_patterns \
498			    -Aclippy::incompatible_msrv \
499			    -Wclippy::mut_mut \
500			    -Wclippy::needless_bitwise_bool \
501			    -Aclippy::needless_lifetimes \
502			    -Wclippy::no_mangle_with_rust_abi \
503			    -Wclippy::ptr_as_ptr \
504			    -Wclippy::ptr_cast_constness \
505			    -Wclippy::ref_as_ptr \
506			    -Wclippy::undocumented_unsafe_blocks \
507			    -Aclippy::uninlined_format_args \
508			    -Wclippy::unnecessary_safety_comment \
509			    -Wclippy::unnecessary_safety_doc \
510			    -Aclippy::unwrap_or_default \
511			    -Wrustdoc::missing_crate_level_docs \
512			    -Wrustdoc::unescaped_backticks
513
514KBUILD_HOSTCFLAGS   := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) \
515		       $(HOSTCFLAGS) -I $(srctree)/scripts/include
516KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS) \
517		       -I $(srctree)/scripts/include
518KBUILD_HOSTRUSTFLAGS := $(rust_common_flags) -O -Cstrip=debuginfo \
519			-Zallow-features=
520KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
521KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
522KBUILD_PROCMACROLDFLAGS := $(or $(PROCMACROLDFLAGS),$(KBUILD_HOSTLDFLAGS))
523
524# Make variables (CC, etc...)
525CPP		= $(CC) -E
526ifneq ($(LLVM),)
527CC		= $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
528LD		= $(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX)
529AR		= $(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX)
530LLVM_LINK	= $(LLVM_PREFIX)llvm-link$(LLVM_SUFFIX)
531NM		= $(LLVM_PREFIX)llvm-nm$(LLVM_SUFFIX)
532OBJCOPY		= $(LLVM_PREFIX)llvm-objcopy$(LLVM_SUFFIX)
533OBJDUMP		= $(LLVM_PREFIX)llvm-objdump$(LLVM_SUFFIX)
534READELF		= $(LLVM_PREFIX)llvm-readelf$(LLVM_SUFFIX)
535STRIP		= $(LLVM_PREFIX)llvm-strip$(LLVM_SUFFIX)
536ifeq ($(filter -fuse-ld=% --ld-path=%,$(KBUILD_HOSTLDFLAGS)),)
537KBUILD_HOSTLDFLAGS += -fuse-ld=lld
538endif
539else
540CC		= $(CROSS_COMPILE)gcc
541LD		= $(CROSS_COMPILE)ld
542AR		= $(CROSS_COMPILE)ar
543NM		= $(CROSS_COMPILE)nm
544OBJCOPY		= $(CROSS_COMPILE)objcopy
545OBJDUMP		= $(CROSS_COMPILE)objdump
546READELF		= $(CROSS_COMPILE)readelf
547STRIP		= $(CROSS_COMPILE)strip
548endif
549RUSTC		= rustc
550RUSTDOC		= rustdoc
551RUSTFMT		= rustfmt
552CLIPPY_DRIVER	= clippy-driver
553BINDGEN		= bindgen
554PAHOLE		= pahole
555RESOLVE_BTFIDS	= $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
556LEX		= flex
557YACC		= bison
558AWK		= awk
559INSTALLKERNEL  := installkernel
560PERL		= perl
561PYTHON3		= python3
562CHECK		= sparse
563BASH		= bash
564KGZIP		= gzip
565KBZIP2		= bzip2
566KLZOP		= lzop
567LZMA		= lzma
568LZ4		= lz4
569XZ		= xz
570ZSTD		= zstd
571TAR		= tar
572
573CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
574		  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
575NOSTDINC_FLAGS :=
576CFLAGS_MODULE   =
577RUSTFLAGS_MODULE =
578AFLAGS_MODULE   =
579LDFLAGS_MODULE  =
580CFLAGS_KERNEL	=
581RUSTFLAGS_KERNEL =
582AFLAGS_KERNEL	=
583LDFLAGS_vmlinux =
584
585# Use USERINCLUDE when you must reference the UAPI directories only.
586USERINCLUDE    := \
587		-I$(srctree)/arch/$(SRCARCH)/include/uapi \
588		-I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
589		-I$(srctree)/include/uapi \
590		-I$(objtree)/include/generated/uapi \
591                -include $(srctree)/include/linux/compiler-version.h \
592                -include $(srctree)/include/linux/kconfig.h
593
594# Use LINUXINCLUDE when you must reference the include/ directory.
595# Needed to be compatible with the O= option
596LINUXINCLUDE    := \
597		-I$(srctree)/arch/$(SRCARCH)/include \
598		-I$(objtree)/arch/$(SRCARCH)/include/generated \
599		-I$(srctree)/include \
600		-I$(objtree)/include \
601		$(USERINCLUDE)
602
603KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
604
605KBUILD_CFLAGS :=
606KBUILD_CFLAGS += -fshort-wchar
607KBUILD_CFLAGS += -funsigned-char
608KBUILD_CFLAGS += -fno-common
609KBUILD_CFLAGS += -fno-PIE
610KBUILD_CFLAGS += -fno-strict-aliasing
611
612KBUILD_CPPFLAGS := -D__KERNEL__
613KBUILD_RUSTFLAGS := $(rust_common_flags) \
614		    -Cpanic=abort -Cembed-bitcode=n -Clto=n \
615		    -Cforce-unwind-tables=n -Ccodegen-units=1 \
616		    -Csymbol-mangling-version=v0 \
617		    -Crelocation-model=static \
618		    -Zfunction-sections=n \
619		    -Wclippy::float_arithmetic
620KBUILD_RUSTFLAGS_OPTION_CHKS :=
621
622KBUILD_AFLAGS_KERNEL :=
623KBUILD_CFLAGS_KERNEL :=
624KBUILD_RUSTFLAGS_KERNEL :=
625KBUILD_AFLAGS_MODULE  := -DMODULE
626KBUILD_CFLAGS_MODULE  := -DMODULE
627KBUILD_RUSTFLAGS_MODULE := --cfg MODULE
628KBUILD_LDFLAGS_MODULE :=
629KBUILD_LDFLAGS :=
630CLANG_FLAGS :=
631
632ifeq ($(KBUILD_CLIPPY),1)
633	RUSTC_OR_CLIPPY_QUIET := CLIPPY
634	RUSTC_OR_CLIPPY = $(CLIPPY_DRIVER)
635else
636	RUSTC_OR_CLIPPY_QUIET := RUSTC
637	RUSTC_OR_CLIPPY = $(RUSTC)
638endif
639
640# Allows the usage of unstable features in stable compilers.
641export RUSTC_BOOTSTRAP := 1
642
643# Allows finding `.clippy.toml` in out-of-srctree builds.
644export CLIPPY_CONF_DIR := $(srctree)
645
646export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG
647export RUSTC RUSTDOC RUSTFMT RUSTC_OR_CLIPPY_QUIET RUSTC_OR_CLIPPY BINDGEN LLVM_LINK
648export HOSTRUSTC KBUILD_HOSTRUSTFLAGS
649export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
650export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
651export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD TAR
652export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS KBUILD_PROCMACROLDFLAGS LDFLAGS_MODULE
653export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS
654
655export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
656export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
657export KBUILD_RUSTFLAGS RUSTFLAGS_KERNEL RUSTFLAGS_MODULE KBUILD_RUSTFLAGS_OPTION_CHKS
658export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
659export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_RUSTFLAGS_MODULE KBUILD_LDFLAGS_MODULE
660export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL KBUILD_RUSTFLAGS_KERNEL
661
662# Files to ignore in find ... statements
663
664export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
665			  -name CVS -o -name .pc -o -name .hg -o -name .git \) \
666			  -prune -o
667
668# ===========================================================================
669# Rules shared between *config targets and build targets
670
671# Basic helpers built in scripts/basic/
672PHONY += scripts_basic
673scripts_basic: KBUILD_HOSTCFLAGS := $(KBUILD_HOSTCFLAGS)
674scripts_basic: KBUILD_HOSTLDFLAGS := $(KBUILD_HOSTLDFLAGS)
675scripts_basic:
676	$(Q)$(MAKE) $(build)=scripts/basic
677
678PHONY += outputmakefile
679ifdef building_out_of_srctree
680# Before starting out-of-tree build, make sure the source tree is clean.
681# outputmakefile generates a Makefile in the output directory, if using a
682# separate output directory. This allows convenient use of make in the
683# output directory.
684# At the same time when output Makefile generated, generate .gitignore to
685# ignore whole output directory
686
687ifdef KBUILD_EXTMOD
688print_env_for_makefile = \
689	echo "export KBUILD_OUTPUT = $(objtree)"; \
690	echo "export KBUILD_EXTMOD = $(realpath $(srcroot))" ; \
691	echo "export KBUILD_EXTMOD_OUTPUT = $(CURDIR)"
692else
693print_env_for_makefile = \
694	echo "export KBUILD_OUTPUT = $(CURDIR)"
695endif
696
697filechk_makefile = { \
698	echo "\# Automatically generated by $(abs_srctree)/Makefile: don't edit"; \
699	$(print_env_for_makefile); \
700	echo "include $(abs_srctree)/Makefile"; \
701	}
702
703PHONY += $(CURDIR)/Makefile
704$(CURDIR)/Makefile: FORCE
705	$(call filechk,makefile)
706
707outputmakefile: $(CURDIR)/Makefile
708ifeq ($(KBUILD_EXTMOD),)
709	@if [ -f $(srctree)/.config -o \
710		 -d $(srctree)/include/config -o \
711		 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
712		echo >&2 "***"; \
713		echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
714		echo >&2 "*** in $(abs_srctree)";\
715		echo >&2 "***"; \
716		false; \
717	fi
718else
719	@if [ -f $(srcroot)/modules.order ]; then \
720		echo >&2 "***"; \
721		echo >&2 "*** The external module source tree is not clean."; \
722		echo >&2 "*** Please run 'make -C $(abs_srctree) M=$(realpath $(srcroot)) clean'"; \
723		echo >&2 "***"; \
724		false; \
725	fi
726endif
727	$(Q)ln -fsn $(srcroot) source
728	$(Q)test -e .gitignore || \
729	{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
730endif
731
732# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
733# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
734# CC_VERSION_TEXT, RUSTC_VERSION_TEXT and PAHOLE_VERSION are referenced from
735# Kconfig (so they need export), and from include/config/auto.conf.cmd to
736# detect the version changes between builds.
737CC_VERSION_TEXT = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1))
738RUSTC_VERSION_TEXT = $(subst $(pound),,$(shell $(RUSTC) --version 2>/dev/null))
739PAHOLE_VERSION = $(shell $(srctree)/scripts/pahole-version.sh $(PAHOLE))
740
741ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
742include $(srctree)/scripts/Makefile.clang
743endif
744
745# Include this also for config targets because some architectures need
746# cc-cross-prefix to determine CROSS_COMPILE.
747ifdef need-compiler
748include $(srctree)/scripts/Makefile.compiler
749endif
750
751ifdef config-build
752# ===========================================================================
753# *config targets only - make sure prerequisites are updated, and descend
754# in scripts/kconfig to make the *config target
755
756# Read arch-specific Makefile to set KBUILD_DEFCONFIG as needed.
757# KBUILD_DEFCONFIG may point out an alternative default configuration
758# used for 'make defconfig'
759include $(srctree)/arch/$(SRCARCH)/Makefile
760export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT RUSTC_VERSION_TEXT PAHOLE_VERSION
761
762config: outputmakefile scripts_basic FORCE
763	$(Q)$(MAKE) $(build)=scripts/kconfig $@
764
765%config: outputmakefile scripts_basic FORCE
766	$(Q)$(MAKE) $(build)=scripts/kconfig $@
767
768else #!config-build
769# ===========================================================================
770# Build targets only - this includes vmlinux, arch-specific targets, clean
771# targets and others. In general all targets except *config targets.
772
773# If building an external module we do not care about the all: rule
774# but instead __all depend on modules
775PHONY += all
776ifeq ($(KBUILD_EXTMOD),)
777__all: all
778else
779__all: modules
780endif
781
782targets :=
783
784# Decide whether to build built-in, modular, or both.
785# Normally, just do built-in.
786
787KBUILD_MODULES :=
788KBUILD_BUILTIN := y
789
790# If we have only "make modules", don't compile built-in objects.
791ifeq ($(MAKECMDGOALS),modules)
792  KBUILD_BUILTIN :=
793endif
794
795# If we have "make <whatever> modules", compile modules
796# in addition to whatever we do anyway.
797# Just "make" or "make all" shall build modules as well
798
799ifneq ($(filter all modules nsdeps compile_commands.json clang-% sbom,$(MAKECMDGOALS)),)
800  KBUILD_MODULES := y
801endif
802
803ifeq ($(MAKECMDGOALS),)
804  KBUILD_MODULES := y
805endif
806
807export KBUILD_MODULES KBUILD_BUILTIN
808
809ifdef need-config
810include $(objtree)/include/config/auto.conf
811endif
812
813CC_FLAGS_DIALECT := -std=gnu11
814# Allow including a tagged struct or union anonymously in another struct/union.
815CC_FLAGS_DIALECT += $(CONFIG_CC_MS_EXTENSIONS)
816# Clang enables warnings about GNU and Microsoft extensions by default, disable
817# them because this is expected with the above options.
818ifdef CONFIG_CC_IS_CLANG
819CC_FLAGS_DIALECT += -Wno-gnu
820CC_FLAGS_DIALECT += -Wno-microsoft-anon-tag
821endif
822export CC_FLAGS_DIALECT
823KBUILD_CFLAGS += $(CC_FLAGS_DIALECT)
824
825ifeq ($(KBUILD_EXTMOD),)
826# Objects we will link into vmlinux / subdirs we need to visit
827core-y		:=
828drivers-y	:=
829libs-y		:= lib/
830endif # KBUILD_EXTMOD
831
832# The all: target is the default when no target is given on the
833# command line.
834# This allow a user to issue only 'make' to build a kernel including modules
835# Defaults to vmlinux, but the arch makefile usually adds further targets
836all: vmlinux
837
838# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
839ifdef CONFIG_FUNCTION_TRACER
840  CC_FLAGS_FTRACE := -pg
841endif
842
843ifdef CONFIG_TRACEPOINTS
844# To check for unused tracepoints (tracepoints that are defined but never
845# called), run with:
846#
847# make UT=1
848#
849# Each unused tracepoints can take up to 5KB of memory in the running kernel.
850# It is best to remove any that are not used.
851#
852# This command line option will be removed when all current unused
853# tracepoints are removed.
854
855ifeq ("$(origin UT)", "command line")
856  WARN_ON_UNUSED_TRACEPOINTS := $(UT)
857endif
858endif # CONFIG_TRACEPOINTS
859
860export WARN_ON_UNUSED_TRACEPOINTS
861
862# Per-version Rust flags. These are like `rust_common_flags`, but may
863# depend on the Rust compiler version (e.g. using `rustc-min-version`).
864#
865# `-Aclippy::precedence`: the lint was extended in Rust 1.85.0 to
866# include bitmasking and shift operations. However, because it generated
867# many hits, in Rust 1.86.0 it was split into a new `precedence_bits`
868# lint which is not enabled by default.
869rust_common_flags_per_version := \
870    $(if $(call rustc-min-version,108600),,-Aclippy::precedence)
871
872rust_common_flags += $(rust_common_flags_per_version)
873KBUILD_HOSTRUSTFLAGS += $(rust_common_flags_per_version) $(HOSTRUSTFLAGS)
874KBUILD_RUSTFLAGS += $(rust_common_flags_per_version)
875
876include $(srctree)/arch/$(SRCARCH)/Makefile
877
878ifdef need-config
879ifdef may-sync-config
880# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
881# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
882# because some architectures define CROSS_COMPILE there.
883include include/config/auto.conf.cmd
884
885$(KCONFIG_CONFIG):
886	@echo >&2 '***'
887	@echo >&2 '*** Configuration file "$@" not found!'
888	@echo >&2 '***'
889	@echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
890	@echo >&2 '*** "make menuconfig" or "make xconfig").'
891	@echo >&2 '***'
892	@/bin/false
893
894# The actual configuration files used during the build are stored in
895# include/generated/ and include/config/. Update them if .config is newer than
896# include/config/auto.conf (which mirrors .config).
897#
898# This exploits the 'multi-target pattern rule' trick.
899# The syncconfig should be executed only once to make all the targets.
900# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
901#
902# Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
903# so you cannot notice that Kconfig is waiting for the user input.
904%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h %/generated/rustc_cfg: $(KCONFIG_CONFIG)
905	$(Q)$(kecho) "  SYNC    $@"
906	$(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
907else # !may-sync-config
908# External modules and some install targets need include/generated/autoconf.h
909# and include/config/auto.conf but do not care if they are up-to-date.
910# Use auto.conf to show the error message
911
912checked-configs := $(addprefix $(objtree)/, include/generated/autoconf.h include/generated/rustc_cfg include/config/auto.conf)
913missing-configs := $(filter-out $(wildcard $(checked-configs)), $(checked-configs))
914
915ifdef missing-configs
916PHONY += $(objtree)/include/config/auto.conf
917
918$(objtree)/include/config/auto.conf:
919	@echo   >&2 '***'
920	@echo   >&2 '***  ERROR: Kernel configuration is invalid. The following files are missing:'
921	@printf >&2 '***    - %s\n' $(missing-configs)
922	@echo   >&2 '***  Run "make oldconfig && make prepare" on kernel source to fix it.'
923	@echo   >&2 '***'
924	@/bin/false
925endif
926
927endif # may-sync-config
928endif # need-config
929
930KBUILD_CFLAGS	+= -fno-delete-null-pointer-checks
931
932ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
933KBUILD_CFLAGS += -O2
934KBUILD_RUSTFLAGS += -Copt-level=2
935else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
936KBUILD_CFLAGS += -Os
937KBUILD_RUSTFLAGS += -Copt-level=s
938endif
939
940# Always set `debug-assertions` and `overflow-checks` because their default
941# depends on `opt-level` and `debug-assertions`, respectively.
942KBUILD_RUSTFLAGS += -Cdebug-assertions=$(if $(CONFIG_RUST_DEBUG_ASSERTIONS),y,n)
943KBUILD_RUSTFLAGS += -Coverflow-checks=$(if $(CONFIG_RUST_OVERFLOW_CHECKS),y,n)
944
945# Tell gcc to never replace conditional load with a non-conditional one
946ifdef CONFIG_CC_IS_GCC
947# gcc-10 renamed --param=allow-store-data-races=0 to
948# -fno-allow-store-data-races.
949KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
950KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
951endif
952
953ifdef CONFIG_READABLE_ASM
954# Disable optimizations that make assembler listings hard to read.
955# reorder blocks reorders the control in the function
956# ipa clone creates specialized cloned functions
957# partial inlining inlines only parts of functions
958KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
959endif
960
961stackp-flags-y                                    := -fno-stack-protector
962stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
963stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
964
965KBUILD_CFLAGS += $(stackp-flags-y)
966
967ifdef CONFIG_FRAME_POINTER
968KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
969KBUILD_RUSTFLAGS += -Cforce-frame-pointers=y
970# Work around rustc bug on compilers without
971# https://github.com/rust-lang/rust/pull/156980.
972KBUILD_RUSTFLAGS += $(if $(call rustc-min-version,109800),,-Zllvm_module_flag=frame-pointer:u32:2:max)
973else
974# Some targets (ARM with Thumb2, for example), can't be built with frame
975# pointers.  For those, we don't have FUNCTION_TRACER automatically
976# select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
977# incompatible with -fomit-frame-pointer with current GCC, so we don't use
978# -fomit-frame-pointer with FUNCTION_TRACER.
979# In the Rust target specification, "frame-pointer" is set explicitly
980# to "may-omit".
981ifndef CONFIG_FUNCTION_TRACER
982KBUILD_CFLAGS	+= -fomit-frame-pointer
983endif
984endif
985
986# Initialize all stack variables with a 0xAA pattern.
987ifdef CONFIG_INIT_STACK_ALL_PATTERN
988KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
989endif
990
991# Initialize all stack variables with a zero value.
992ifdef CONFIG_INIT_STACK_ALL_ZERO
993KBUILD_CFLAGS	+= -ftrivial-auto-var-init=zero
994ifdef CONFIG_CC_HAS_AUTO_VAR_INIT_ZERO_ENABLER
995# https://github.com/llvm/llvm-project/issues/44842
996CC_AUTO_VAR_INIT_ZERO_ENABLER := -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
997export CC_AUTO_VAR_INIT_ZERO_ENABLER
998KBUILD_CFLAGS	+= $(CC_AUTO_VAR_INIT_ZERO_ENABLER)
999endif
1000endif
1001
1002ifdef CONFIG_KMALLOC_PARTITION_TYPED
1003# KMALLOC_PARTITION_CACHES_NR + 1
1004KBUILD_CFLAGS	+= -falloc-token-max=16
1005endif
1006
1007ifdef CONFIG_CC_IS_CLANG
1008ifdef CONFIG_CC_HAS_COUNTED_BY_PTR
1009KBUILD_CFLAGS	+= -fexperimental-late-parse-attributes
1010endif
1011endif
1012
1013# Explicitly clear padding bits during variable initialization
1014KBUILD_CFLAGS += $(call cc-option,-fzero-init-padding-bits=all)
1015
1016# While VLAs have been removed, GCC produces unreachable stack probes
1017# for the randomize_kstack_offset feature. Disable it for all compilers.
1018KBUILD_CFLAGS	+= $(call cc-option, -fno-stack-clash-protection)
1019
1020# Get details on warnings generated due to GCC value tracking.
1021KBUILD_CFLAGS	+= $(call cc-option, -fdiagnostics-show-context=2)
1022
1023# Show inlining notes for __attribute__((warning/error)) call chains.
1024# GCC supports this unconditionally while Clang 23+ provides a flag.
1025KBUILD_CFLAGS	+= $(call cc-option, -fdiagnostics-show-inlining-chain)
1026
1027# Clear used registers at func exit (to reduce data lifetime and ROP gadgets).
1028ifdef CONFIG_ZERO_CALL_USED_REGS
1029KBUILD_CFLAGS	+= -fzero-call-used-regs=used-gpr
1030endif
1031
1032ifdef CONFIG_FUNCTION_TRACER
1033ifdef CONFIG_FTRACE_MCOUNT_USE_CC
1034  CC_FLAGS_FTRACE	+= -mrecord-mcount
1035  ifdef CONFIG_HAVE_NOP_MCOUNT
1036    ifeq ($(call cc-option-yn, -mnop-mcount),y)
1037      CC_FLAGS_FTRACE	+= -mnop-mcount
1038      CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
1039    endif
1040  endif
1041endif
1042ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
1043  ifdef CONFIG_HAVE_OBJTOOL_NOP_MCOUNT
1044    CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
1045  endif
1046endif
1047ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
1048  ifdef CONFIG_HAVE_C_RECORDMCOUNT
1049    BUILD_C_RECORDMCOUNT := y
1050    export BUILD_C_RECORDMCOUNT
1051  endif
1052endif
1053ifdef CONFIG_HAVE_FENTRY
1054  # s390-linux-gnu-gcc did not support -mfentry until gcc-9.
1055  ifeq ($(call cc-option-yn, -mfentry),y)
1056    CC_FLAGS_FTRACE	+= -mfentry
1057    CC_FLAGS_USING	+= -DCC_USING_FENTRY
1058  endif
1059endif
1060export CC_FLAGS_FTRACE
1061KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
1062KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
1063endif
1064
1065# We trigger additional mismatches with less inlining
1066ifdef CONFIG_DEBUG_SECTION_MISMATCH
1067KBUILD_CFLAGS += -fno-inline-functions-called-once
1068endif
1069
1070# `rustc`'s `-Zfunction-sections` applies to data too (as of 1.59.0).
1071ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
1072KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
1073KBUILD_RUSTFLAGS_KERNEL += -Zfunction-sections=y
1074LDFLAGS_vmlinux += --gc-sections
1075endif
1076
1077ifdef CONFIG_SHADOW_CALL_STACK
1078ifndef CONFIG_DYNAMIC_SCS
1079CC_FLAGS_SCS	:= -fsanitize=shadow-call-stack
1080KBUILD_CFLAGS	+= $(CC_FLAGS_SCS)
1081KBUILD_RUSTFLAGS += -Zsanitizer=shadow-call-stack
1082endif
1083export CC_FLAGS_SCS
1084endif
1085
1086ifdef CONFIG_RUST_INLINE_HELPERS
1087# `rustc` normally emits traps for unreachable paths during code generation.
1088# With inline helpers, Clang performs code generation from the linked bitcode
1089# instead, so request the same behavior explicitly. Otherwise `objtool` may
1090# follow an impossible Rust path into the next function.
1091CC_FLAGS_RUST_INLINE_HELPERS := -mllvm -trap-unreachable \
1092				-mllvm -no-trap-after-noreturn
1093export CC_FLAGS_RUST_INLINE_HELPERS
1094endif
1095
1096ifdef CONFIG_LTO_CLANG
1097ifdef CONFIG_LTO_CLANG_FULL
1098CC_FLAGS_LTO	:= -flto
1099else
1100CC_FLAGS_LTO	:= -flto=thin -fsplit-lto-unit
1101
1102# These LLVM options were initially added with only in-process ThinLTO
1103# support, so avoid distributed ThinLTO support for now.
1104ifdef CONFIG_LTO_CLANG_THIN
1105KBUILD_LDFLAGS += $(call ld-option,--lto-whole-program-visibility -mllvm -always-rename-promoted-locals=false)
1106endif
1107endif
1108CC_FLAGS_LTO	+= -fvisibility=hidden
1109
1110# Limit inlining across translation units to reduce binary size
1111KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
1112endif
1113
1114ifdef CONFIG_LTO
1115KBUILD_CFLAGS	+= -fno-lto $(CC_FLAGS_LTO)
1116KBUILD_AFLAGS	+= -fno-lto
1117export CC_FLAGS_LTO
1118endif
1119
1120ifdef CONFIG_CFI
1121CC_FLAGS_CFI	:= -fsanitize=kcfi
1122ifdef CONFIG_CFI_ICALL_NORMALIZE_INTEGERS
1123	CC_FLAGS_CFI	+= -fsanitize-cfi-icall-experimental-normalize-integers
1124endif
1125ifdef CONFIG_FINEIBT_BHI
1126	CC_FLAGS_CFI	+= -fsanitize-kcfi-arity
1127endif
1128ifdef CONFIG_RUST
1129	# Always pass -Zsanitizer-cfi-normalize-integers as CONFIG_RUST selects
1130	# CONFIG_CFI_ICALL_NORMALIZE_INTEGERS.
1131	# Disable function merging as LLVM incorrectly merges functions with different KCFI types.
1132	RUSTC_FLAGS_CFI   := -Zsanitizer=kcfi -Zsanitizer-cfi-normalize-integers -Zmerge-functions=disabled
1133	KBUILD_RUSTFLAGS += $(RUSTC_FLAGS_CFI)
1134	export RUSTC_FLAGS_CFI
1135endif
1136KBUILD_CFLAGS	+= $(CC_FLAGS_CFI)
1137export CC_FLAGS_CFI
1138endif
1139
1140# Architectures can define flags to add/remove for floating-point support
1141CC_FLAGS_FPU	+= -D_LINUX_FPU_COMPILATION_UNIT
1142export CC_FLAGS_FPU
1143export CC_FLAGS_NO_FPU
1144
1145ifneq ($(CONFIG_FUNCTION_ALIGNMENT),0)
1146# Set the minimal function alignment. Use the newer GCC option
1147# -fmin-function-alignment if it is available, or fall back to -falign-funtions.
1148# See also CONFIG_CC_HAS_SANE_FUNCTION_ALIGNMENT.
1149ifdef CONFIG_CC_HAS_MIN_FUNCTION_ALIGNMENT
1150KBUILD_CFLAGS += -fmin-function-alignment=$(CONFIG_FUNCTION_ALIGNMENT)
1151else
1152KBUILD_CFLAGS += -falign-functions=$(CONFIG_FUNCTION_ALIGNMENT)
1153endif
1154endif
1155
1156# arch Makefile may override CC so keep this after arch Makefile is included
1157NOSTDINC_FLAGS += -nostdinc
1158
1159# To gain proper coverage for CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE,
1160# the kernel uses only C99 flexible arrays for dynamically sized trailing
1161# arrays. Enforce this for everything that may examine structure sizes and
1162# perform bounds checking.
1163KBUILD_CFLAGS += $(call cc-option, -fstrict-flex-arrays=3)
1164
1165# disable invalid "can't wrap" optimizations for signed / pointers
1166KBUILD_CFLAGS	+= -fno-strict-overflow
1167
1168# Make sure -fstack-check isn't enabled (like gentoo apparently did)
1169KBUILD_CFLAGS  += -fno-stack-check
1170
1171# conserve stack if available
1172ifdef CONFIG_CC_IS_GCC
1173KBUILD_CFLAGS   += -fconserve-stack
1174endif
1175
1176# Ensure compilers do not transform certain loops into calls to wcslen()
1177KBUILD_CFLAGS += -fno-builtin-wcslen
1178
1179CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage
1180ifdef CONFIG_CC_IS_GCC
1181CFLAGS_GCOV	+= -fno-tree-loop-im
1182# Use atomic counter updates to avoid concurrent-access crashes in GCOV.
1183# Only enable if -fprofile-update=prefer-atomic does not introduce new
1184# undefined symbols (e.g. libatomic calls that the kernel cannot link).
1185CFLAGS_GCOV	+= $(call try-run,\
1186	echo 'long long x; void f(void){x++;}' | \
1187	$(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -w -fprofile-arcs \
1188	-ftest-coverage -x c - -c -o "$$TMP.base" && \
1189	echo 'long long x; void f(void){x++;}' | \
1190	$(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -w -fprofile-arcs \
1191	-ftest-coverage -fprofile-update=prefer-atomic \
1192	-x c - -c -o "$$TMP" && \
1193	$(NM) "$$TMP.base" | grep ' U ' > "$$TMP.ubase" || true ; \
1194	$(NM) "$$TMP" | grep ' U ' > "$$TMP.utest" || true ; \
1195	cmp -s "$$TMP.ubase" "$$TMP.utest",\
1196	-fprofile-update=prefer-atomic)
1197endif
1198export CFLAGS_GCOV
1199
1200# change __FILE__ to the relative path to the source directory
1201ifdef building_out_of_srctree
1202KBUILD_CPPFLAGS += -fmacro-prefix-map=$(srcroot)/=
1203ifeq ($(call rustc-option-yn, --remap-path-scope=macro),y)
1204KBUILD_RUSTFLAGS += --remap-path-prefix=$(srcroot)/= --remap-path-scope=macro
1205endif
1206endif
1207
1208# include additional Makefiles when needed
1209include-y			:= scripts/Makefile.warn
1210include-$(CONFIG_DEBUG_INFO)	+= scripts/Makefile.debug
1211include-$(CONFIG_DEBUG_INFO_BTF)+= scripts/Makefile.btf
1212include-$(CONFIG_KASAN)		+= scripts/Makefile.kasan
1213include-$(CONFIG_KCSAN)		+= scripts/Makefile.kcsan
1214include-$(CONFIG_KMSAN)		+= scripts/Makefile.kmsan
1215include-$(CONFIG_UBSAN)		+= scripts/Makefile.ubsan
1216include-$(CONFIG_KCOV)		+= scripts/Makefile.kcov
1217include-$(CONFIG_RANDSTRUCT)	+= scripts/Makefile.randstruct
1218include-$(CONFIG_KSTACK_ERASE)	+= scripts/Makefile.kstack_erase
1219include-$(CONFIG_AUTOFDO_CLANG)	+= scripts/Makefile.autofdo
1220include-$(CONFIG_PROPELLER_CLANG)	+= scripts/Makefile.propeller
1221include-$(CONFIG_WARN_CONTEXT_ANALYSIS) += scripts/Makefile.context-analysis
1222include-$(CONFIG_GCC_PLUGINS)	+= scripts/Makefile.gcc-plugins
1223
1224include $(addprefix $(srctree)/, $(include-y))
1225
1226# scripts/Makefile.gcc-plugins is intentionally included last.
1227# Do not add $(call cc-option,...) below this line. When you build the kernel
1228# from the clean source tree, the GCC plugins do not exist at this point.
1229
1230# Add user supplied CPPFLAGS, AFLAGS, CFLAGS and RUSTFLAGS as the last assignments
1231KBUILD_CPPFLAGS += $(KCPPFLAGS)
1232KBUILD_AFLAGS   += $(KAFLAGS)
1233KBUILD_CFLAGS   += $(KCFLAGS)
1234KBUILD_RUSTFLAGS += $(KRUSTFLAGS)
1235
1236KBUILD_LDFLAGS_MODULE += --build-id=sha1
1237LDFLAGS_vmlinux += --build-id=sha1
1238
1239# Specific code, such as outlined KASAN checks, may be placed in
1240# COMDAT-deduplicated sections. Use --force-group-allocation to resolve these
1241# groups when linking modules. The option is available from ld.bfd 2.29 and
1242# ld.lld 19.1.0.
1243KBUILD_LDFLAGS_MODULE += $(call ld-option,--force-group-allocation)
1244
1245KBUILD_LDFLAGS	+= -z noexecstack
1246ifeq ($(CONFIG_LD_IS_BFD),y)
1247KBUILD_LDFLAGS	+= $(call ld-option,--no-warn-rwx-segments)
1248endif
1249
1250ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1251LDFLAGS_vmlinux	+= -X
1252endif
1253
1254ifeq ($(CONFIG_RELR),y)
1255# ld.lld before 15 did not support -z pack-relative-relocs.
1256LDFLAGS_vmlinux	+= $(call ld-option,--pack-dyn-relocs=relr,-z pack-relative-relocs)
1257endif
1258
1259# We never want expected sections to be placed heuristically by the
1260# linker. All sections should be explicitly named in the linker script.
1261ifdef CONFIG_LD_ORPHAN_WARN
1262LDFLAGS_vmlinux += --orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL)
1263endif
1264
1265ifneq ($(CONFIG_ARCH_VMLINUX_NEEDS_RELOCS),)
1266LDFLAGS_vmlinux	+= --emit-relocs --discard-none
1267endif
1268
1269# Align the architecture of userspace programs with the kernel
1270USERFLAGS_FROM_KERNEL := --target=%
1271
1272ifdef CONFIG_ARCH_USERFLAGS
1273KBUILD_USERCFLAGS += $(CONFIG_ARCH_USERFLAGS)
1274KBUILD_USERLDFLAGS += $(CONFIG_ARCH_USERFLAGS)
1275else
1276# If not overridden also inherit the bit size
1277USERFLAGS_FROM_KERNEL += -m32 -m64
1278endif
1279
1280KBUILD_USERCFLAGS  += $(filter $(USERFLAGS_FROM_KERNEL), $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS))
1281KBUILD_USERLDFLAGS += $(filter $(USERFLAGS_FROM_KERNEL), $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS))
1282
1283# userspace programs are linked via the compiler, use the correct linker
1284ifdef CONFIG_CC_IS_CLANG
1285KBUILD_USERLDFLAGS += --ld-path=$(LD)
1286endif
1287
1288# make the checker run with the right architecture
1289CHECKFLAGS += --arch=$(ARCH)
1290
1291# insure the checker run with the right endianness
1292CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1293
1294# the checker needs the correct machine size
1295CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1296
1297# Validate the checker is available and functional
1298ifneq ($(KBUILD_CHECKSRC), 0)
1299  ifneq ($(shell $(srctree)/scripts/checker-valid.sh $(CHECK) $(CHECKFLAGS)), 1)
1300    $(warning C=$(KBUILD_CHECKSRC) specified, but $(CHECK) is not available or not up to date)
1301    KBUILD_CHECKSRC = 0
1302  endif
1303endif
1304
1305# Default kernel image to build when no specific target is given.
1306# KBUILD_IMAGE may be overruled on the command line or
1307# set in the environment
1308# Also any assignments in arch/$(ARCH)/Makefile take precedence over
1309# this default value
1310export KBUILD_IMAGE ?= vmlinux
1311
1312#
1313# INSTALL_PATH specifies where to place the updated kernel and system map
1314# images. Default is /boot, but you can set it to other values
1315export	INSTALL_PATH ?= /boot
1316
1317#
1318# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1319# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1320# an argument if needed. Otherwise it defaults to the kernel install path
1321#
1322export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1323
1324#
1325# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1326# relocations required by build roots.  This is not defined in the
1327# makefile but the argument can be passed to make if needed.
1328#
1329
1330MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1331export MODLIB
1332
1333PHONY += prepare0
1334
1335ifeq ($(KBUILD_EXTMOD),)
1336
1337build-dir	:= .
1338clean-dirs	:= $(sort . Documentation \
1339		     $(patsubst %/,%,$(filter %/, $(core-) \
1340			$(drivers-) $(libs-))))
1341
1342export ARCH_CORE	:= $(core-y)
1343export ARCH_LIB		:= $(filter %/, $(libs-y))
1344export ARCH_DRIVERS	:= $(drivers-y) $(drivers-m)
1345# Externally visible symbols (used by link-vmlinux.sh)
1346
1347KBUILD_VMLINUX_OBJS := built-in.a $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1348KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1349
1350export KBUILD_VMLINUX_OBJS KBUILD_VMLINUX_LIBS
1351export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1352
1353ifdef CONFIG_TRIM_UNUSED_KSYMS
1354# For the kernel to actually contain only the needed exported symbols,
1355# we have to build modules as well to determine what those symbols are.
1356KBUILD_MODULES := y
1357endif
1358
1359PHONY += vmlinux_a
1360vmlinux_a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt FORCE
1361	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_a
1362
1363vmlinux.a: vmlinux_a
1364	@:
1365
1366PHONY += vmlinux_o
1367vmlinux_o: vmlinux.a $(KBUILD_VMLINUX_LIBS)
1368	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o
1369
1370vmlinux.o: vmlinux_o
1371	@:
1372
1373PHONY += vmlinux
1374# LDFLAGS_vmlinux in the top Makefile defines linker flags for the top vmlinux,
1375# not for decompressors. LDFLAGS_vmlinux in arch/*/boot/compressed/Makefile is
1376# unrelated; the decompressors just happen to have the same base name,
1377# arch/*/boot/compressed/vmlinux.
1378# Export LDFLAGS_vmlinux only to scripts/Makefile.vmlinux.
1379#
1380# _LDFLAGS_vmlinux is a workaround for the 'private export' bug:
1381#   https://savannah.gnu.org/bugs/?61463
1382# For Make > 4.4, the following simple code will work:
1383#  vmlinux: private export LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1384vmlinux: private _LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1385vmlinux: export LDFLAGS_vmlinux = $(_LDFLAGS_vmlinux)
1386vmlinux: vmlinux.o $(KBUILD_LDS) modpost
1387	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux
1388
1389# The actual objects are generated when descending,
1390# make sure no implicit rule kicks in
1391$(sort $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)): . ;
1392
1393ifeq ($(origin KERNELRELEASE),file)
1394filechk_kernel.release = $(srctree)/scripts/setlocalversion $(srctree)
1395else
1396filechk_kernel.release = echo $(KERNELRELEASE)
1397endif
1398
1399# Store (new) KERNELRELEASE string in include/config/kernel.release
1400include/config/kernel.release: FORCE
1401	$(call filechk,kernel.release)
1402
1403# Additional helpers built in scripts/
1404# Carefully list dependencies so we do not try to build scripts twice
1405# in parallel
1406PHONY += scripts
1407scripts: scripts_basic scripts_dtc
1408	$(Q)$(MAKE) $(build)=$(@)
1409
1410# Things we need to do before we recursively start building the kernel
1411# or the modules are listed in "prepare".
1412# A multi level approach is used. prepareN is processed before prepareN-1.
1413# archprepare is used in arch Makefiles and when processed asm symlink,
1414# version.h and scripts_basic is processed / created.
1415
1416PHONY += prepare archprepare
1417
1418archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1419	asm-generic $(version_h) include/generated/utsrelease.h \
1420	include/generated/compile.h include/generated/autoconf.h \
1421	include/generated/rustc_cfg remove-stale-files
1422
1423prepare0: archprepare
1424	$(Q)$(MAKE) $(build)=scripts/mod
1425	$(Q)$(MAKE) $(build)=. prepare
1426
1427# All the preparing..
1428prepare: prepare0
1429ifdef CONFIG_RUST
1430	+$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh
1431	$(Q)$(MAKE) $(build)=rust
1432endif
1433
1434PHONY += remove-stale-files
1435remove-stale-files:
1436	$(Q)$(srctree)/scripts/remove-stale-files
1437
1438# Support for using generic headers in asm-generic
1439asm-generic := -f $(srctree)/scripts/Makefile.asm-headers obj
1440
1441PHONY += asm-generic uapi-asm-generic
1442asm-generic: uapi-asm-generic
1443	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1444	generic=include/asm-generic
1445uapi-asm-generic:
1446	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1447	generic=include/uapi/asm-generic
1448
1449# Generate some files
1450# ---------------------------------------------------------------------------
1451
1452# KERNELRELEASE can change from a few different places, meaning version.h
1453# needs to be updated, so this check is forced on all builds
1454
1455uts_len := 64
1456define filechk_utsrelease.h
1457	if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1458	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1459	  exit 1;                                                         \
1460	fi;                                                               \
1461	echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1462endef
1463
1464define filechk_version.h
1465	if [ $(SUBLEVEL) -gt 255 ]; then                                 \
1466		echo \#define LINUX_VERSION_CODE $(shell                 \
1467		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1468	else                                                             \
1469		echo \#define LINUX_VERSION_CODE $(shell                 \
1470		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1471	fi;                                                              \
1472	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
1473	((c) > 255 ? 255 : (c)))';                                       \
1474	echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
1475	echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
1476	echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1477endef
1478
1479$(version_h): private PATCHLEVEL := $(or $(PATCHLEVEL), 0)
1480$(version_h): private SUBLEVEL := $(or $(SUBLEVEL), 0)
1481$(version_h): FORCE
1482	$(call filechk,version.h)
1483
1484include/generated/utsrelease.h: include/config/kernel.release FORCE
1485	$(call filechk,utsrelease.h)
1486
1487filechk_compile.h = $(srctree)/scripts/mkcompile_h \
1488	"$(UTS_MACHINE)" "$(CONFIG_CC_VERSION_TEXT)" "$(LD)"
1489
1490include/generated/compile.h: FORCE
1491	$(call filechk,compile.h)
1492
1493PHONY += headerdep
1494headerdep:
1495	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1496	$(srctree)/scripts/headerdep.pl -I$(srctree)/include
1497
1498# ---------------------------------------------------------------------------
1499# Kernel headers
1500
1501#Default location for installed headers
1502export INSTALL_HDR_PATH = $(objtree)/usr
1503
1504quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1505      cmd_headers_install = \
1506	mkdir -p $(INSTALL_HDR_PATH); \
1507	rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1508	usr/include $(INSTALL_HDR_PATH)
1509
1510PHONY += headers_install
1511headers_install: headers
1512	$(call cmd,headers_install)
1513
1514PHONY += archheaders archscripts
1515
1516hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1517
1518PHONY += headers
1519headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders
1520ifdef HEADER_ARCH
1521	$(Q)$(MAKE) -f $(srctree)/Makefile HEADER_ARCH= SRCARCH=$(HEADER_ARCH) headers
1522else
1523	$(Q)$(MAKE) $(hdr-inst)=include/uapi
1524	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1525endif
1526
1527ifdef CONFIG_HEADERS_INSTALL
1528prepare: headers
1529endif
1530
1531PHONY += usr_gen_init_cpio
1532usr_gen_init_cpio: scripts_basic
1533	$(Q)$(MAKE) $(build)=usr usr/gen_init_cpio
1534
1535PHONY += scripts_unifdef
1536scripts_unifdef: scripts_basic
1537	$(Q)$(MAKE) $(build)=scripts scripts/unifdef
1538
1539PHONY += scripts_gen_packed_field_checks
1540scripts_gen_packed_field_checks: scripts_basic
1541	$(Q)$(MAKE) $(build)=scripts scripts/gen_packed_field_checks
1542
1543# ---------------------------------------------------------------------------
1544# Install
1545
1546# Many distributions have the custom install script, /sbin/installkernel.
1547# If DKMS is installed, 'make install' will eventually recurse back
1548# to this Makefile to build and install external modules.
1549# Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
1550
1551quiet_cmd_install = INSTALL $(INSTALL_PATH)
1552      cmd_install = unset sub_make_done; $(srctree)/scripts/install.sh
1553
1554# ---------------------------------------------------------------------------
1555# vDSO install
1556
1557PHONY += vdso_install
1558vdso_install: export INSTALL_FILES = $(vdso-install-y)
1559vdso_install:
1560	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vdsoinst
1561
1562# ---------------------------------------------------------------------------
1563# Tools
1564
1565ifdef CONFIG_OBJTOOL
1566prepare: tools/objtool
1567endif
1568
1569ifdef CONFIG_BPF
1570ifdef CONFIG_DEBUG_INFO_BTF
1571prepare: tools/bpf/resolve_btfids
1572endif
1573endif
1574
1575# The tools build system is not a part of Kbuild and tends to introduce
1576# its own unique issues. If you need to integrate a new tool into Kbuild,
1577# please consider locating that tool outside the tools/ tree and using the
1578# standard Kbuild "hostprogs" syntax instead of adding a new tools/* entry
1579# here. See Documentation/kbuild/makefiles.rst for details.
1580
1581PHONY += resolve_btfids_clean
1582
1583resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1584
1585# tools/bpf/resolve_btfids directory might not exist
1586# in output directory, skip its clean in that case
1587resolve_btfids_clean:
1588ifneq ($(wildcard $(resolve_btfids_O)),)
1589	$(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1590endif
1591
1592PHONY += objtool_clean objtool_mrproper
1593
1594objtool_O = $(abspath $(objtree))/tools/objtool
1595
1596objtool_clean objtool_mrproper:
1597ifneq ($(wildcard $(objtool_O)),)
1598	$(Q)$(MAKE) -sC $(abs_srctree)/tools/objtool O=$(objtool_O) srctree=$(abs_srctree) $(patsubst objtool_%,%,$@)
1599endif
1600
1601tools/: FORCE
1602	$(Q)mkdir -p $(objtree)/tools
1603	$(Q)$(MAKE) O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1604
1605tools/%: FORCE
1606	$(Q)mkdir -p $(objtree)/tools
1607	$(Q)$(MAKE) O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1608
1609# ---------------------------------------------------------------------------
1610# Kernel selftest
1611
1612PHONY += kselftest
1613kselftest: headers
1614	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1615
1616kselftest-%: headers FORCE
1617	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1618
1619PHONY += kselftest-merge
1620kselftest-merge:
1621	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1622	$(Q)find $(srctree)/tools/testing/selftests -name config -o -name config.$(UTS_MACHINE) | \
1623		xargs $(srctree)/scripts/kconfig/merge_config.sh -y -m $(objtree)/.config
1624	$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1625
1626# ---------------------------------------------------------------------------
1627# Devicetree files
1628
1629ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1630dtstree := arch/$(SRCARCH)/boot/dts
1631endif
1632
1633dtbindingtree := Documentation/devicetree/bindings
1634
1635%.yaml: dtbs_prepare
1636	$(Q)$(MAKE) $(build)=$(dtbindingtree) \
1637		    $(dtbindingtree)/$(patsubst %.yaml,%.example.dtb,$@) dt_binding_check_one
1638
1639ifneq ($(dtstree),)
1640
1641%.dtb: dtbs_prepare
1642	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1643
1644%.dtbo: dtbs_prepare
1645	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1646
1647PHONY += dtbs dtbs_prepare dtbs_install dtbs_check
1648dtbs: dtbs_prepare
1649	$(Q)$(MAKE) $(build)=$(dtstree) need-dtbslist=1
1650
1651# include/config/kernel.release is actually needed when installing DTBs because
1652# INSTALL_DTBS_PATH contains $(KERNELRELEASE). However, we do not want to make
1653# dtbs_install depend on it as dtbs_install may run as root.
1654dtbs_prepare: include/config/kernel.release scripts_dtc
1655
1656ifneq ($(filter dtbs_check %.yaml, $(MAKECMDGOALS)),)
1657export CHECK_DTBS=y
1658endif
1659
1660ifneq ($(CHECK_DTBS),)
1661dtbs_prepare: dt_binding_schemas
1662endif
1663
1664dtbs_check: dtbs
1665
1666dtbs_install:
1667	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.dtbinst obj=$(dtstree)
1668
1669ifdef CONFIG_OF_EARLY_FLATTREE
1670all: dtbs
1671endif
1672
1673ifdef CONFIG_GENERIC_BUILTIN_DTB
1674vmlinux: dtbs
1675endif
1676
1677endif
1678
1679PHONY += scripts_dtc
1680scripts_dtc: scripts_basic
1681	$(Q)$(MAKE) $(build)=scripts/dtc
1682
1683ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1684export CHECK_DTBS=y
1685endif
1686
1687PHONY += dt_binding_check dt_binding_schemas
1688dt_binding_check: dt_binding_schemas scripts_dtc
1689	$(Q)$(MAKE) $(build)=$(dtbindingtree) $@
1690
1691dt_binding_schemas:
1692	$(Q)$(MAKE) $(build)=$(dtbindingtree)
1693
1694PHONY += dt_compatible_check
1695dt_compatible_check: dt_binding_schemas
1696	$(Q)$(MAKE) $(build)=$(dtbindingtree) $@
1697
1698PHONY += dt_style_selftest
1699dt_style_selftest:
1700	$(Q)$(srctree)/scripts/dtc/dt-style-selftest/run.sh
1701
1702# ---------------------------------------------------------------------------
1703# Modules
1704
1705ifdef CONFIG_MODULES
1706
1707# By default, build modules as well
1708
1709all: modules
1710
1711# When we're building modules with modversions, we need to consider
1712# the built-in objects during the descend as well, in order to
1713# make sure the checksums are up to date before we record them.
1714ifdef CONFIG_MODVERSIONS
1715  KBUILD_BUILTIN := y
1716endif
1717
1718# Build modules
1719#
1720
1721# *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFO_BTF_MODULES
1722# is an exception.
1723ifdef CONFIG_DEBUG_INFO_BTF_MODULES
1724KBUILD_BUILTIN := y
1725modules: vmlinux
1726endif
1727
1728modules: modules_prepare
1729
1730# Target to prepare building external modules
1731modules_prepare: prepare
1732	$(Q)$(MAKE) $(build)=scripts scripts/module.lds
1733
1734endif # CONFIG_MODULES
1735
1736###
1737# Cleaning is done on three levels.
1738# make clean     Delete most generated files
1739#                Leave enough to build external modules
1740# make mrproper  Delete the current configuration, and all generated files
1741# make distclean Remove editor backup files, patch leftover files and the like
1742
1743# Directories & files removed with 'make clean'
1744CLEAN_FILES += vmlinux.symvers modules-only.symvers \
1745	       modules.builtin modules.builtin.modinfo modules.nsdeps \
1746	       modules.builtin.ranges vmlinux.o.map vmlinux.unstripped \
1747	       vmlinux.thinlto-index builtin.order \
1748	       compile_commands.json rust/test \
1749	       rust-project.json .vmlinux.objs .vmlinux.export.c \
1750	       .builtin-dtbs-list .builtin-dtbs.S sbom-*.spdx.json
1751
1752# Directories & files removed with 'make mrproper'
1753MRPROPER_FILES += include/config include/generated          \
1754		  arch/$(SRCARCH)/include/generated .objdiff \
1755		  debian snap tar-install PKGBUILD pacman \
1756		  .config .config.old .version \
1757		  Module.symvers \
1758		  certs/signing_key.pem \
1759		  certs/x509.genkey \
1760		  vmlinux-gdb.py \
1761		  rpmbuild \
1762		  rust/libmacros.so rust/libmacros.dylib \
1763		  rust/libpin_init_internal.so rust/libpin_init_internal.dylib \
1764		  rust/libzerocopy_derive.so rust/libzerocopy_derive.dylib
1765
1766# clean - Delete most, but leave enough to build external modules
1767#
1768clean: private rm-files := $(CLEAN_FILES)
1769
1770PHONY += archclean vmlinuxclean
1771
1772vmlinuxclean:
1773	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1774	$(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1775
1776clean: archclean vmlinuxclean resolve_btfids_clean objtool_clean
1777
1778# mrproper - Delete all generated files, including .config
1779#
1780mrproper: private rm-files := $(MRPROPER_FILES)
1781mrproper-dirs      := $(addprefix _mrproper_,scripts)
1782
1783PHONY += $(mrproper-dirs) mrproper
1784$(mrproper-dirs):
1785	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1786
1787mrproper: clean objtool_mrproper $(mrproper-dirs)
1788	$(call cmd,rmfiles)
1789	@find . $(RCS_FIND_IGNORE) \
1790		\( -name '*.rmeta' \) \
1791		-type f -print | xargs rm -f
1792
1793# distclean
1794#
1795PHONY += distclean
1796
1797distclean: mrproper
1798	@find . $(RCS_FIND_IGNORE) \
1799		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1800		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
1801		-o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1802		-o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1803		-type f -print | xargs rm -f
1804
1805
1806# Packaging of the kernel to various formats
1807# ---------------------------------------------------------------------------
1808
1809modules-cpio-pkg: usr_gen_init_cpio
1810
1811%src-pkg: FORCE
1812	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1813%pkg: include/config/kernel.release FORCE
1814	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1815
1816# Brief documentation of the typical targets used
1817# ---------------------------------------------------------------------------
1818
1819boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1820boards := $(sort $(notdir $(boards)))
1821board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1822board-dirs := $(sort $(notdir $(board-dirs:/=)))
1823
1824PHONY += help
1825help:
1826	@echo  'Cleaning targets:'
1827	@echo  '  clean		  - Remove most generated files but keep the config and'
1828	@echo  '                    enough build support to build external modules'
1829	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
1830	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
1831	@echo  ''
1832	@$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1833	@echo  ''
1834	@echo  'Other generic targets:'
1835	@echo  '  all		  - Build all targets marked with [*]'
1836	@echo  '* vmlinux	  - Build the bare kernel'
1837	@echo  '* modules	  - Build all modules'
1838	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1839	@echo  '  vdso_install    - Install unstripped vdso to INSTALL_MOD_PATH (default: /)'
1840	@echo  '  dir/            - Build all files in dir and below'
1841	@echo  '  dir/file.[ois]  - Build specified target only'
1842	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1843	@echo  '                    (requires compiler support for LLVM assembly generation)'
1844	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1845	@echo  '                    (requires a recent binutils and recent build (System.map))'
1846	@echo  '  dir/file.ko     - Build module including final link'
1847	@echo  '  modules_prepare - Set up for building external modules'
1848	@echo  '  tags/TAGS	  - Generate tags file for editors'
1849	@echo  '  cscope	  - Generate cscope index'
1850	@echo  '  gtags           - Generate GNU GLOBAL index'
1851	@echo  '  kernelrelease	  - Output the release version string (use with make -s)'
1852	@echo  '  kernelversion	  - Output the version stored in Makefile (use with make -s)'
1853	@echo  '  image_name	  - Output the image name (use with make -s)'
1854	@echo  '  headers	  - Build ready-to-install UAPI headers in usr/include'
1855	@echo  '  headers_install - Install sanitised kernel UAPI headers to INSTALL_HDR_PATH'; \
1856	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1857	 echo  ''
1858	@echo  'Static analysers:'
1859	@echo  '  checkstack        - Generate a list of stack hogs and consider all functions'
1860	@echo  '                      with a stack size larger than MINSTACKSIZE (default: 100)'
1861	@echo  '  versioncheck      - Sanity check on version.h usage'
1862	@echo  '  includecheck      - Check for duplicate included header files'
1863	@echo  '  headerdep         - Detect inclusion cycles in headers'
1864	@echo  '  coccicheck        - Check with Coccinelle'
1865	@echo  '  kconfig-sym-check - Check for dangling Kconfig symbol references'
1866	@echo  '  clang-analyzer    - Check with clang static analyzer'
1867	@echo  '  clang-tidy        - Check with clang-tidy'
1868	@echo  ''
1869	@echo  'Tools:'
1870	@echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1871	@echo  '  sbom            - Generate Software Bill of Materials'
1872	@echo  ''
1873	@echo  'Kernel selftest:'
1874	@echo  '  kselftest         - Build and run kernel selftest'
1875	@echo  '                      Build, install, and boot kernel before'
1876	@echo  '                      running kselftest on it'
1877	@echo  '                      Run as root for full coverage'
1878	@echo  '  kselftest-all     - Build kernel selftest'
1879	@echo  '  kselftest-install - Build and install kernel selftest'
1880	@echo  '  kselftest-clean   - Remove all generated kselftest files'
1881	@echo  '  kselftest-merge   - Merge all the config dependencies of'
1882	@echo  '		      kselftest to existing .config.'
1883	@echo  ''
1884	@echo  'Rust targets:'
1885	@echo  '  rustavailable   - Checks whether the Rust toolchain is'
1886	@echo  '		    available and, if not, explains why.'
1887	@echo  '  rustfmt	  - Reformat all the Rust code in the kernel'
1888	@echo  '  rustfmtcheck	  - Checks if all the Rust code in the kernel'
1889	@echo  '		    is formatted, printing a diff otherwise.'
1890	@echo  '  rustdoc	  - Generate Rust documentation'
1891	@echo  '		    (requires kernel .config)'
1892	@echo  '  rusttest        - Runs the Rust tests'
1893	@echo  '                    (requires kernel .config; downloads external repos)'
1894	@echo  '  rust-analyzer	  - Generate rust-project.json rust-analyzer support file'
1895	@echo  '		    (requires kernel .config)'
1896	@echo  '  dir/file.[os]   - Build specified target only'
1897	@echo  '  dir/file.rsi    - Build macro expanded source, similar to C preprocessing.'
1898	@echo  '                    Run with RUSTFMT=n to skip reformatting if needed.'
1899	@echo  '                    The output is not intended to be compilable.'
1900	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1901	@echo  ''
1902	@$(if $(dtstree), \
1903		echo 'Devicetree:'; \
1904		echo '* dtbs               - Build device tree blobs for enabled boards'; \
1905		echo '  dtbs_install       - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1906		echo '  dt_binding_check   - Validate device tree binding documents and examples'; \
1907		echo '  dt_binding_schemas - Build processed device tree binding schemas'; \
1908		echo '  dt_style_selftest  - Run dt-check-style fixture tests'; \
1909		echo '  dtbs_check         - Validate device tree source files';\
1910		echo '')
1911
1912	@echo 'Userspace tools targets:'
1913	@echo '  use "make tools/help"'
1914	@echo '  or  "cd tools; make help"'
1915	@echo  ''
1916	@echo  'Kernel packaging:'
1917	@$(MAKE) -f $(srctree)/scripts/Makefile.package help
1918	@echo  ''
1919	@echo  'Documentation targets:'
1920	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1921	@echo  ''
1922	@echo  'Architecture-specific targets ($(SRCARCH)):'
1923	@$(or $(archhelp),\
1924		echo '  No architecture-specific help defined for $(SRCARCH)')
1925	@echo  ''
1926	@$(if $(boards), \
1927		$(foreach b, $(boards), \
1928		printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1929		echo '')
1930	@$(if $(board-dirs), \
1931		$(foreach b, $(board-dirs), \
1932		printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1933		printf "  %-16s - Show all of the above\\n" help-boards; \
1934		echo '')
1935
1936	@echo  '  make V=n   [targets] 1: verbose build'
1937	@echo  '                       2: give reason for rebuild of target'
1938	@echo  '                       V=1 and V=2 can be combined with V=12'
1939	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1940	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1941	@echo  '                       (sparse by default)'
1942	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1943	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1944	@echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3,c,e where'
1945	@echo  '		1: warnings which may be relevant and do not occur too often'
1946	@echo  '		2: warnings which occur quite often but may still be relevant'
1947	@echo  '		3: more obscure warnings, can most likely be ignored'
1948	@echo  '		c: extra checks in the configuration stage (Kconfig)'
1949	@echo  '		e: warnings are being treated as errors'
1950	@echo  '		Multiple levels can be combined with W=12 or W=123'
1951	@echo  '  make UT=1   [targets] Warn if a tracepoint is defined but not used.'
1952	@echo  '          [ This will be removed when all current unused tracepoints are eliminated. ]'
1953	@$(if $(dtstree), \
1954		echo '  make CHECK_DTBS=1 [targets] Check all generated dtb files against schema'; \
1955		echo '         This can be applied both to "dtbs" and to individual "foo.dtb" targets' ; \
1956		)
1957	@echo  ''
1958	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
1959	@echo  'For further info see the ./README file'
1960
1961
1962help-board-dirs := $(addprefix help-,$(board-dirs))
1963
1964help-boards: $(help-board-dirs)
1965
1966boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1967
1968$(help-board-dirs): help-%:
1969	@echo  'Architecture-specific targets ($(SRCARCH) $*):'
1970	@$(if $(boards-per-dir), \
1971		$(foreach b, $(boards-per-dir), \
1972		printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1973		echo '')
1974
1975
1976# Documentation targets
1977# ---------------------------------------------------------------------------
1978DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1979	       linkcheckdocs dochelp refcheckdocs texinfodocs infodocs mandocs \
1980	       htmldocs-redirects
1981
1982PHONY += $(DOC_TARGETS)
1983$(DOC_TARGETS):
1984	$(Q)$(MAKE) $(build)=Documentation $@
1985
1986
1987# Rust targets
1988# ---------------------------------------------------------------------------
1989
1990# "Is Rust available?" target
1991PHONY += rustavailable
1992rustavailable:
1993	+$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh && echo "Rust is available!"
1994
1995# Documentation target
1996#
1997# Using the singular to avoid running afoul of `no-dot-config-targets`.
1998PHONY += rustdoc
1999rustdoc: prepare
2000	$(Q)$(MAKE) $(build)=rust $@
2001
2002# Testing target
2003PHONY += rusttest
2004rusttest: prepare
2005	$(Q)$(MAKE) $(build)=rust $@
2006
2007# Formatting targets
2008#
2009# Generated files as well as vendored crates are skipped.
2010PHONY += rustfmt rustfmtcheck
2011
2012rustfmt:
2013	$(Q)find $(srctree) $(RCS_FIND_IGNORE) \
2014		\( \
2015			-path $(srctree)/rust/proc-macro2 \
2016			-o -path $(srctree)/rust/quote \
2017			-o -path $(srctree)/rust/syn \
2018			-o -path $(srctree)/rust/zerocopy \
2019			-o -path $(srctree)/rust/zerocopy-derive \
2020		\) -prune -o \
2021		-type f -a -name '*.rs' -a ! -name '*generated*' -print \
2022		| xargs $(RUSTFMT) $(rustfmt_flags)
2023
2024rustfmtcheck: rustfmt_flags = --check
2025rustfmtcheck: rustfmt
2026
2027# Misc
2028# ---------------------------------------------------------------------------
2029
2030PHONY += misc-check
2031misc-check:
2032	$(Q)$(srctree)/scripts/misc-check
2033
2034all: misc-check
2035
2036PHONY += scripts_gdb
2037scripts_gdb: prepare0
2038	$(Q)$(MAKE) $(build)=scripts/gdb
2039	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
2040
2041ifdef CONFIG_GDB_SCRIPTS
2042all: scripts_gdb
2043endif
2044
2045else # KBUILD_EXTMOD
2046
2047filechk_kernel.release = echo $(KERNELRELEASE)
2048
2049###
2050# External module support.
2051# When building external modules the kernel used as basis is considered
2052# read-only, and no consistency checks are made and the make
2053# system is not used on the basis kernel. If updates are required
2054# in the basis kernel ordinary make commands (without M=...) must be used.
2055
2056# We are always building only modules.
2057KBUILD_BUILTIN :=
2058KBUILD_MODULES := y
2059
2060build-dir := .
2061
2062clean-dirs := .
2063clean: private rm-files := Module.symvers modules.nsdeps compile_commands.json
2064
2065PHONY += prepare
2066# now expand this into a simple variable to reduce the cost of shell evaluations
2067prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT)
2068prepare: PAHOLE_VERSION := $(PAHOLE_VERSION)
2069prepare:
2070	@if [ "$(CC_VERSION_TEXT)" != "$(CONFIG_CC_VERSION_TEXT)" ]; then \
2071		echo >&2 "warning: the compiler differs from the one used to build the kernel"; \
2072		echo >&2 "  The kernel was built by: $(CONFIG_CC_VERSION_TEXT)"; \
2073		echo >&2 "  You are using:           $(CC_VERSION_TEXT)"; \
2074	fi
2075	@if [ "$(PAHOLE_VERSION)" != "$(CONFIG_PAHOLE_VERSION)" ]; then \
2076		echo >&2 "warning: pahole version differs from the one used to build the kernel"; \
2077		echo >&2 "  The kernel was built with: $(CONFIG_PAHOLE_VERSION)"; \
2078		echo >&2 "  You are using:             $(PAHOLE_VERSION)"; \
2079	fi
2080
2081PHONY += help
2082help:
2083	@echo  '  Building external modules.'
2084	@echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
2085	@echo  ''
2086	@echo  '  modules         - default target, build the module(s)'
2087	@echo  '  modules_install - install the module'
2088	@echo  '  clean           - remove generated files in module directory only'
2089	@echo  '  rust-analyzer	  - generate rust-project.json rust-analyzer support file'
2090	@echo  ''
2091
2092ifndef CONFIG_MODULES
2093modules modules_install: __external_modules_error
2094__external_modules_error:
2095	@echo >&2 '***'
2096	@echo >&2 '*** The present kernel disabled CONFIG_MODULES.'
2097	@echo >&2 '*** You cannot build or install external modules.'
2098	@echo >&2 '***'
2099	@false
2100endif
2101
2102endif # KBUILD_EXTMOD
2103
2104# ---------------------------------------------------------------------------
2105# Modules
2106
2107PHONY += modules modules_install modules_sign modules_prepare
2108
2109modules_install:
2110	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst \
2111	sign-only=$(if $(filter modules_install,$(MAKECMDGOALS)),,y)
2112
2113ifeq ($(CONFIG_MODULE_SIG),y)
2114# modules_sign is a subset of modules_install.
2115# 'make modules_install modules_sign' is equivalent to 'make modules_install'.
2116modules_sign: modules_install
2117	@:
2118else
2119modules_sign:
2120	@echo >&2 '***'
2121	@echo >&2 '*** CONFIG_MODULE_SIG is disabled. You cannot sign modules.'
2122	@echo >&2 '***'
2123	@false
2124endif
2125
2126ifdef CONFIG_MODULES
2127
2128modules.order: $(build-dir)
2129	@:
2130
2131# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
2132# This is solely useful to speed up test compiles.
2133modules: modpost
2134ifneq ($(KBUILD_MODPOST_NOFINAL),1)
2135	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
2136endif
2137
2138PHONY += modules_check
2139modules_check: modules.order
2140	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
2141
2142else # CONFIG_MODULES
2143
2144modules:
2145	@:
2146
2147KBUILD_MODULES :=
2148
2149endif # CONFIG_MODULES
2150
2151PHONY += modpost
2152modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \
2153	 $(if $(KBUILD_MODULES), modules_check)
2154	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
2155
2156# Single targets
2157# ---------------------------------------------------------------------------
2158# To build individual files in subdirectories, you can do like this:
2159#
2160#   make foo/bar/baz.s
2161#
2162# The supported suffixes for single-target are listed in 'single-targets'
2163#
2164# To build only under specific subdirectories, you can do like this:
2165#
2166#   make foo/bar/baz/
2167
2168ifdef single-build
2169
2170# .ko is special because modpost is needed
2171single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
2172single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \
2173		$(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko)))
2174
2175$(single-ko): single_modules
2176	@:
2177$(single-no-ko): $(build-dir)
2178	@:
2179
2180# Remove modules.order when done because it is not the real one.
2181PHONY += single_modules
2182single_modules: $(single-no-ko) modules_prepare
2183	$(Q){ $(foreach m, $(single-ko), echo $(m:%.ko=%.o);) } > modules.order
2184	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
2185ifneq ($(KBUILD_MODPOST_NOFINAL),1)
2186	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
2187endif
2188	$(Q)rm -f modules.order
2189
2190single-goals := $(addprefix $(build-dir)/, $(single-no-ko))
2191
2192KBUILD_MODULES := y
2193
2194endif
2195
2196prepare: outputmakefile
2197
2198# Preset locale variables to speed up the build process. Limit locale
2199# tweaks to this spot to avoid wrong language settings when running
2200# make menuconfig etc.
2201# Error messages still appears in the original language
2202PHONY += $(build-dir)
2203$(build-dir): prepare
2204	$(Q)$(MAKE) $(build)=$@ need-builtin=1 need-modorder=1 $(single-goals)
2205
2206clean-dirs := $(addprefix _clean_, $(clean-dirs))
2207PHONY += $(clean-dirs) clean
2208$(clean-dirs):
2209	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
2210
2211clean: $(clean-dirs)
2212	$(call cmd,rmfiles)
2213	@find . $(RCS_FIND_IGNORE) \
2214		\( -name '*.[aios]' -o -name '*.rsi' -o -name '*.ko' -o -name '.*.cmd' \
2215		-o -name '*.ko.*' -o -name '*.o.thinlto.bc' \
2216		-o -name '*.dtb' -o -name '*.dtbo' \
2217		-o -name '*.dtb.S' -o -name '*.dtbo.S' \
2218		-o -name '*.dt.yaml' -o -name 'dtbs-list' \
2219		-o -name '*.dwo' -o -name '*.lst' \
2220		-o -name '*.su' -o -name '*.mod' \
2221		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
2222		-o -name '*.lex.c' -o -name '*.tab.[ch]' \
2223		-o -name '*.asn1.[ch]' \
2224		-o -name '*.symtypes' -o -name 'modules.order' \
2225		-o -name '*.c.[012]*.*' \
2226		-o -name '*.ll' \
2227		-o -name '*.gcno' \
2228		-o -name '*.long-type-*.txt' \
2229		\) -type f -print \
2230		-o -name '.tmp_*' -print \
2231		| xargs rm -rf
2232
2233# Generate tags for editors
2234# ---------------------------------------------------------------------------
2235quiet_cmd_tags = GEN     $@
2236      cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
2237
2238tags TAGS cscope gtags: FORCE
2239	$(call cmd,tags)
2240
2241# Generate rust-project.json (a file that describes the structure of non-Cargo
2242# Rust projects) for rust-analyzer (an implementation of the Language Server
2243# Protocol).
2244PHONY += rust-analyzer
2245rust-analyzer:
2246	+$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh
2247ifdef KBUILD_EXTMOD
2248# FIXME: external modules must not descend into a sub-directory of the kernel
2249	$(Q)$(MAKE) $(build)=$(objtree)/rust src=$(srctree)/rust $@
2250else
2251	$(Q)$(MAKE) $(build)=rust $@
2252endif
2253
2254# Script to generate missing namespace dependencies
2255# ---------------------------------------------------------------------------
2256
2257PHONY += nsdeps
2258nsdeps: export KBUILD_NSDEPS=1
2259nsdeps: modules
2260	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
2261
2262# Script to generate .spdx.json SBOM documents describing the build
2263# ---------------------------------------------------------------------------
2264
2265ifdef building_out_of_srctree
2266sbom_targets := sbom-source.spdx.json
2267endif
2268sbom_targets += sbom-build.spdx.json sbom-output.spdx.json
2269quiet_cmd_sbom = GEN     $(sbom_targets)
2270      cmd_sbom = printf "%s\n" "$(KBUILD_IMAGE)" >"$(tmp-target)"; \
2271                 $(if $(CONFIG_MODULES),sed 's/\.o$$/.ko/' $(objtree)/modules.order >> "$(tmp-target)";) \
2272                 $(PYTHON3) $(srctree)/scripts/sbom/sbom.py \
2273                     --src-tree $(abspath $(srctree)) \
2274                     --obj-tree $(abspath $(objtree)) \
2275                     --roots-file "$(tmp-target)" \
2276                     --output-directory $(abspath $(objtree)) \
2277                     --generate-spdx \
2278                     --package-license "GPL-2.0 WITH Linux-syscall-note" \
2279                     --package-version "$(KERNELVERSION)" \
2280                     --write-output-on-error;
2281PHONY += sbom
2282sbom: $(notdir $(KBUILD_IMAGE)) include/generated/autoconf.h $(if $(CONFIG_MODULES),modules modules.order)
2283	$(call cmd,sbom)
2284
2285# Clang Tooling
2286# ---------------------------------------------------------------------------
2287
2288quiet_cmd_gen_compile_commands = GEN     $@
2289      cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
2290
2291compile_commands.json: $(srctree)/scripts/clang-tools/gen_compile_commands.py \
2292	$(if $(KBUILD_EXTMOD),, vmlinux.a $(KBUILD_VMLINUX_LIBS)) \
2293	$(if $(CONFIG_MODULES), modules.order) FORCE
2294	$(call if_changed,gen_compile_commands)
2295
2296targets += compile_commands.json
2297
2298PHONY += clang-tidy clang-analyzer
2299
2300ifdef CONFIG_CC_IS_CLANG
2301quiet_cmd_clang_tools = CHECK   $<
2302      cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
2303
2304clang-tidy clang-analyzer: compile_commands.json
2305	$(call cmd,clang_tools)
2306else
2307clang-tidy clang-analyzer:
2308	@echo "$@ requires CC=clang" >&2
2309	@false
2310endif
2311
2312# Scripts to check various things for consistency
2313# ---------------------------------------------------------------------------
2314
2315PHONY += includecheck versioncheck coccicheck kconfig-sym-check
2316
2317includecheck:
2318	find $(srctree)/* $(RCS_FIND_IGNORE) \
2319		-name '*.[hcS]' -type f -print | sort \
2320		| xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
2321
2322versioncheck:
2323	find $(srctree)/* $(RCS_FIND_IGNORE) \
2324		-name '*.[hcS]' -type f -print | sort \
2325		| xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
2326
2327coccicheck:
2328	$(Q)$(BASH) $(srctree)/scripts/$@
2329
2330kconfig-sym-check:
2331	$(Q)$(PERL) $(srctree)/scripts/kconfig/kconfig-sym-check.pl $(srctree) $(KCONFIG_SYM_CHECK_EXCLUDES)
2332
2333PHONY += checkstack kernelrelease kernelversion image_name
2334
2335# UML needs a little special treatment here.  It wants to use the host
2336# toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
2337# else wants $(ARCH), including people doing cross-builds, which means
2338# that $(SUBARCH) doesn't work here.
2339ifeq ($(ARCH), um)
2340CHECKSTACK_ARCH := $(SUBARCH)
2341else
2342CHECKSTACK_ARCH := $(ARCH)
2343endif
2344MINSTACKSIZE	?= 100
2345checkstack:
2346	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
2347	$(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH) $(MINSTACKSIZE)
2348
2349kernelrelease:
2350	@$(filechk_kernel.release)
2351
2352kernelversion:
2353	@echo $(KERNELVERSION)
2354
2355image_name:
2356	@echo $(KBUILD_IMAGE)
2357
2358PHONY += run-command
2359run-command:
2360	$(Q)$(KBUILD_RUN_COMMAND)
2361
2362quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
2363      cmd_rmfiles = rm -rf $(rm-files)
2364
2365# read saved command lines for existing targets
2366existing-targets := $(wildcard $(sort $(targets)))
2367
2368-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
2369
2370endif # config-build
2371endif # mixed-build
2372endif # need-sub-make
2373
2374PHONY += FORCE
2375FORCE:
2376
2377# Declare the contents of the PHONY variable as phony.  We keep that
2378# information in a variable so we can use it in if_changed and friends.
2379.PHONY: $(PHONY)
2380