xref: /openbmc/linux/Makefile (revision 18afb028)
1# SPDX-License-Identifier: GPL-2.0
2VERSION = 6
3PATCHLEVEL = 6
4SUBLEVEL = 1
5EXTRAVERSION =
6NAME = Hurr durr I'ma ninja sloth
7
8# *DOCUMENTATION*
9# To see a list of typical targets execute "make help"
10# More info can be located in ./README
11# Comments in this file are targeted only to the developer, do not
12# expect to learn how to build the kernel reading this file.
13
14ifeq ($(filter undefine,$(.FEATURES)),)
15$(error GNU Make >= 3.82 is required. Your Make version is $(MAKE_VERSION))
16endif
17
18$(if $(filter __%, $(MAKECMDGOALS)), \
19	$(error targets prefixed with '__' are only for internal use))
20
21# That's our default target when none is given on the command line
22PHONY := __all
23__all:
24
25# We are using a recursive build, so we need to do a little thinking
26# to get the ordering right.
27#
28# Most importantly: sub-Makefiles should only ever modify files in
29# their own directory. If in some directory we have a dependency on
30# a file in another dir (which doesn't happen often, but it's often
31# unavoidable when linking the built-in.a targets which finally
32# turn into vmlinux), we will call a sub make in that other dir, and
33# after that we are sure that everything which is in that other dir
34# is now up to date.
35#
36# The only cases where we need to modify files which have global
37# effects are thus separated out and done before the recursive
38# descending is started. They are now explicitly listed as the
39# prepare rule.
40
41this-makefile := $(lastword $(MAKEFILE_LIST))
42export abs_srctree := $(realpath $(dir $(this-makefile)))
43export abs_objtree := $(CURDIR)
44
45ifneq ($(sub_make_done),1)
46
47# Do not use make's built-in rules and variables
48# (this increases performance and avoids hard-to-debug behaviour)
49MAKEFLAGS += -rR
50
51# Avoid funny character set dependencies
52unexport LC_ALL
53LC_COLLATE=C
54LC_NUMERIC=C
55export LC_COLLATE LC_NUMERIC
56
57# Avoid interference with shell env settings
58unexport GREP_OPTIONS
59
60# Beautify output
61# ---------------------------------------------------------------------------
62#
63# Most of build commands in Kbuild start with "cmd_". You can optionally define
64# "quiet_cmd_*". If defined, the short log is printed. Otherwise, no log from
65# that command is printed by default.
66#
67# e.g.)
68#    quiet_cmd_depmod = DEPMOD  $(MODLIB)
69#          cmd_depmod = $(srctree)/scripts/depmod.sh $(DEPMOD) $(KERNELRELEASE)
70#
71# A simple variant is to prefix commands with $(Q) - that's useful
72# for commands that shall be hidden in non-verbose mode.
73#
74#    $(Q)$(MAKE) $(build)=scripts/basic
75#
76# If KBUILD_VERBOSE contains 1, the whole command is echoed.
77# If KBUILD_VERBOSE contains 2, the reason for rebuilding is printed.
78#
79# To put more focus on warnings, be less verbose as default
80# Use 'make V=1' to see the full commands
81
82ifeq ("$(origin V)", "command line")
83  KBUILD_VERBOSE = $(V)
84endif
85
86quiet = quiet_
87Q = @
88
89ifneq ($(findstring 1, $(KBUILD_VERBOSE)),)
90  quiet =
91  Q =
92endif
93
94# If the user is running make -s (silent mode), suppress echoing of
95# commands
96# make-4.0 (and later) keep single letter options in the 1st word of MAKEFLAGS.
97
98ifeq ($(filter 3.%,$(MAKE_VERSION)),)
99short-opts := $(firstword -$(MAKEFLAGS))
100else
101short-opts := $(filter-out --%,$(MAKEFLAGS))
102endif
103
104ifneq ($(findstring s,$(short-opts)),)
105quiet=silent_
106override KBUILD_VERBOSE :=
107endif
108
109export quiet Q KBUILD_VERBOSE
110
111# Call a source code checker (by default, "sparse") as part of the
112# C compilation.
113#
114# Use 'make C=1' to enable checking of only re-compiled files.
115# Use 'make C=2' to enable checking of *all* source files, regardless
116# of whether they are re-compiled or not.
117#
118# See the file "Documentation/dev-tools/sparse.rst" for more details,
119# including where to get the "sparse" utility.
120
121ifeq ("$(origin C)", "command line")
122  KBUILD_CHECKSRC = $(C)
123endif
124ifndef KBUILD_CHECKSRC
125  KBUILD_CHECKSRC = 0
126endif
127
128export KBUILD_CHECKSRC
129
130# Enable "clippy" (a linter) as part of the Rust compilation.
131#
132# Use 'make CLIPPY=1' to enable it.
133ifeq ("$(origin CLIPPY)", "command line")
134  KBUILD_CLIPPY := $(CLIPPY)
135endif
136
137export KBUILD_CLIPPY
138
139# Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
140# directory of external module to build. Setting M= takes precedence.
141ifeq ("$(origin M)", "command line")
142  KBUILD_EXTMOD := $(M)
143endif
144
145$(if $(word 2, $(KBUILD_EXTMOD)), \
146	$(error building multiple external modules is not supported))
147
148$(foreach x, % :, $(if $(findstring $x, $(KBUILD_EXTMOD)), \
149	$(error module directory path cannot contain '$x')))
150
151# Remove trailing slashes
152ifneq ($(filter %/, $(KBUILD_EXTMOD)),)
153KBUILD_EXTMOD := $(shell dirname $(KBUILD_EXTMOD).)
154endif
155
156export KBUILD_EXTMOD
157
158# Kbuild will save output files in the current working directory.
159# This does not need to match to the root of the kernel source tree.
160#
161# For example, you can do this:
162#
163#  cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
164#
165# If you want to save output files in a different location, there are
166# two syntaxes to specify it.
167#
168# 1) O=
169# Use "make O=dir/to/store/output/files/"
170#
171# 2) Set KBUILD_OUTPUT
172# Set the environment variable KBUILD_OUTPUT to point to the output directory.
173# export KBUILD_OUTPUT=dir/to/store/output/files/; make
174#
175# The O= assignment takes precedence over the KBUILD_OUTPUT environment
176# variable.
177
178# Do we want to change the working directory?
179ifeq ("$(origin O)", "command line")
180  KBUILD_OUTPUT := $(O)
181endif
182
183ifneq ($(KBUILD_OUTPUT),)
184# Make's built-in functions such as $(abspath ...), $(realpath ...) cannot
185# expand a shell special character '~'. We use a somewhat tedious way here.
186abs_objtree := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) && pwd)
187$(if $(abs_objtree),, \
188     $(error failed to create output directory "$(KBUILD_OUTPUT)"))
189
190# $(realpath ...) resolves symlinks
191abs_objtree := $(realpath $(abs_objtree))
192endif # ifneq ($(KBUILD_OUTPUT),)
193
194ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
195$(error source directory cannot contain spaces or colons)
196endif
197
198ifneq ($(filter 3.%,$(MAKE_VERSION)),)
199# 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
200# We need to invoke sub-make to avoid implicit rules in the top Makefile.
201need-sub-make := 1
202# Cancel implicit rules for this Makefile.
203$(this-makefile): ;
204endif
205
206export sub_make_done := 1
207
208endif # sub_make_done
209
210ifeq ($(abs_objtree),$(CURDIR))
211# Suppress "Entering directory ..." if we are at the final work directory.
212no-print-directory := --no-print-directory
213else
214# Recursion to show "Entering directory ..."
215need-sub-make := 1
216endif
217
218ifeq ($(filter --no-print-directory, $(MAKEFLAGS)),)
219# If --no-print-directory is unset, recurse once again to set it.
220# You may end up recursing into __sub-make twice. This is needed due to the
221# behavior change in GNU Make 4.4.1.
222need-sub-make := 1
223endif
224
225ifeq ($(need-sub-make),1)
226
227PHONY += $(MAKECMDGOALS) __sub-make
228
229$(filter-out $(this-makefile), $(MAKECMDGOALS)) __all: __sub-make
230	@:
231
232# Invoke a second make in the output directory, passing relevant variables
233__sub-make:
234	$(Q)$(MAKE) $(no-print-directory) -C $(abs_objtree) \
235	-f $(abs_srctree)/Makefile $(MAKECMDGOALS)
236
237else # need-sub-make
238
239# We process the rest of the Makefile if this is the final invocation of make
240
241ifeq ($(abs_srctree),$(abs_objtree))
242        # building in the source tree
243        srctree := .
244	building_out_of_srctree :=
245else
246        ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
247                # building in a subdirectory of the source tree
248                srctree := ..
249        else
250                srctree := $(abs_srctree)
251        endif
252	building_out_of_srctree := 1
253endif
254
255ifneq ($(KBUILD_ABS_SRCTREE),)
256srctree := $(abs_srctree)
257endif
258
259objtree		:= .
260VPATH		:= $(srctree)
261
262export building_out_of_srctree srctree objtree VPATH
263
264# To make sure we do not include .config for any of the *config targets
265# catch them early, and hand them over to scripts/kconfig/Makefile
266# It is allowed to specify more targets when calling make, including
267# mixing *config targets and build targets.
268# For example 'make oldconfig all'.
269# Detect when mixed targets is specified, and make a second invocation
270# of make so .config is not included in this case either (for *config).
271
272version_h := include/generated/uapi/linux/version.h
273
274clean-targets := %clean mrproper cleandocs
275no-dot-config-targets := $(clean-targets) \
276			 cscope gtags TAGS tags help% %docs check% coccicheck \
277			 $(version_h) headers headers_% archheaders archscripts \
278			 %asm-generic kernelversion %src-pkg dt_binding_check \
279			 outputmakefile rustavailable rustfmt rustfmtcheck
280# Installation targets should not require compiler. Unfortunately, vdso_install
281# is an exception where build artifacts may be updated. This must be fixed.
282no-compiler-targets := $(no-dot-config-targets) install dtbs_install \
283			headers_install modules_install modules_sign kernelrelease image_name
284no-sync-config-targets := $(no-dot-config-targets) %install modules_sign kernelrelease \
285			  image_name
286single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.rsi %.s %.symtypes %/
287
288config-build	:=
289mixed-build	:=
290need-config	:= 1
291need-compiler	:= 1
292may-sync-config	:= 1
293single-build	:=
294
295ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
296	ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
297		need-config :=
298	endif
299endif
300
301ifneq ($(filter $(no-compiler-targets), $(MAKECMDGOALS)),)
302	ifeq ($(filter-out $(no-compiler-targets), $(MAKECMDGOALS)),)
303		need-compiler :=
304	endif
305endif
306
307ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
308	ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
309		may-sync-config :=
310	endif
311endif
312
313ifneq ($(KBUILD_EXTMOD),)
314	may-sync-config :=
315endif
316
317ifeq ($(KBUILD_EXTMOD),)
318        ifneq ($(filter %config,$(MAKECMDGOALS)),)
319		config-build := 1
320                ifneq ($(words $(MAKECMDGOALS)),1)
321			mixed-build := 1
322                endif
323        endif
324endif
325
326# We cannot build single targets and the others at the same time
327ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
328	single-build := 1
329	ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
330		mixed-build := 1
331	endif
332endif
333
334# For "make -j clean all", "make -j mrproper defconfig all", etc.
335ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
336        ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
337		mixed-build := 1
338        endif
339endif
340
341# install and modules_install need also be processed one by one
342ifneq ($(filter install,$(MAKECMDGOALS)),)
343        ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
344		mixed-build := 1
345        endif
346endif
347
348ifdef mixed-build
349# ===========================================================================
350# We're called with mixed targets (*config and build targets).
351# Handle them one by one.
352
353PHONY += $(MAKECMDGOALS) __build_one_by_one
354
355$(MAKECMDGOALS): __build_one_by_one
356	@:
357
358__build_one_by_one:
359	$(Q)set -e; \
360	for i in $(MAKECMDGOALS); do \
361		$(MAKE) -f $(srctree)/Makefile $$i; \
362	done
363
364else # !mixed-build
365
366include $(srctree)/scripts/Kbuild.include
367
368# Read KERNELRELEASE from include/config/kernel.release (if it exists)
369KERNELRELEASE = $(call read-file, include/config/kernel.release)
370KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
371export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
372
373include $(srctree)/scripts/subarch.include
374
375# Cross compiling and selecting different set of gcc/bin-utils
376# ---------------------------------------------------------------------------
377#
378# When performing cross compilation for other architectures ARCH shall be set
379# to the target architecture. (See arch/* for the possibilities).
380# ARCH can be set during invocation of make:
381# make ARCH=ia64
382# Another way is to have ARCH set in the environment.
383# The default ARCH is the host where make is executed.
384
385# CROSS_COMPILE specify the prefix used for all executables used
386# during compilation. Only gcc and related bin-utils executables
387# are prefixed with $(CROSS_COMPILE).
388# CROSS_COMPILE can be set on the command line
389# make CROSS_COMPILE=ia64-linux-
390# Alternatively CROSS_COMPILE can be set in the environment.
391# Default value for CROSS_COMPILE is not to prefix executables
392# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
393ARCH		?= $(SUBARCH)
394
395# Architecture as present in compile.h
396UTS_MACHINE 	:= $(ARCH)
397SRCARCH 	:= $(ARCH)
398
399# Additional ARCH settings for x86
400ifeq ($(ARCH),i386)
401        SRCARCH := x86
402endif
403ifeq ($(ARCH),x86_64)
404        SRCARCH := x86
405endif
406
407# Additional ARCH settings for sparc
408ifeq ($(ARCH),sparc32)
409       SRCARCH := sparc
410endif
411ifeq ($(ARCH),sparc64)
412       SRCARCH := sparc
413endif
414
415# Additional ARCH settings for parisc
416ifeq ($(ARCH),parisc64)
417       SRCARCH := parisc
418endif
419
420export cross_compiling :=
421ifneq ($(SRCARCH),$(SUBARCH))
422cross_compiling := 1
423endif
424
425KCONFIG_CONFIG	?= .config
426export KCONFIG_CONFIG
427
428# SHELL used by kbuild
429CONFIG_SHELL := sh
430
431HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
432HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
433HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
434
435ifneq ($(LLVM),)
436ifneq ($(filter %/,$(LLVM)),)
437LLVM_PREFIX := $(LLVM)
438else ifneq ($(filter -%,$(LLVM)),)
439LLVM_SUFFIX := $(LLVM)
440endif
441
442HOSTCC	= $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
443HOSTCXX	= $(LLVM_PREFIX)clang++$(LLVM_SUFFIX)
444else
445HOSTCC	= gcc
446HOSTCXX	= g++
447endif
448HOSTRUSTC = rustc
449HOSTPKG_CONFIG	= pkg-config
450
451KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
452			 -O2 -fomit-frame-pointer -std=gnu11
453KBUILD_USERCFLAGS  := $(KBUILD_USERHOSTCFLAGS) $(USERCFLAGS)
454KBUILD_USERLDFLAGS := $(USERLDFLAGS)
455
456# These flags apply to all Rust code in the tree, including the kernel and
457# host programs.
458export rust_common_flags := --edition=2021 \
459			    -Zbinary_dep_depinfo=y \
460			    -Dunsafe_op_in_unsafe_fn -Drust_2018_idioms \
461			    -Dunreachable_pub -Dnon_ascii_idents \
462			    -Wmissing_docs \
463			    -Drustdoc::missing_crate_level_docs \
464			    -Dclippy::correctness -Dclippy::style \
465			    -Dclippy::suspicious -Dclippy::complexity \
466			    -Dclippy::perf \
467			    -Dclippy::let_unit_value -Dclippy::mut_mut \
468			    -Dclippy::needless_bitwise_bool \
469			    -Dclippy::needless_continue \
470			    -Dclippy::no_mangle_with_rust_abi \
471			    -Wclippy::dbg_macro
472
473KBUILD_HOSTCFLAGS   := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
474KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
475KBUILD_HOSTRUSTFLAGS := $(rust_common_flags) -O -Cstrip=debuginfo \
476			-Zallow-features= $(HOSTRUSTFLAGS)
477KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
478KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
479
480# Make variables (CC, etc...)
481CPP		= $(CC) -E
482ifneq ($(LLVM),)
483CC		= $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
484LD		= $(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX)
485AR		= $(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX)
486NM		= $(LLVM_PREFIX)llvm-nm$(LLVM_SUFFIX)
487OBJCOPY		= $(LLVM_PREFIX)llvm-objcopy$(LLVM_SUFFIX)
488OBJDUMP		= $(LLVM_PREFIX)llvm-objdump$(LLVM_SUFFIX)
489READELF		= $(LLVM_PREFIX)llvm-readelf$(LLVM_SUFFIX)
490STRIP		= $(LLVM_PREFIX)llvm-strip$(LLVM_SUFFIX)
491else
492CC		= $(CROSS_COMPILE)gcc
493LD		= $(CROSS_COMPILE)ld
494AR		= $(CROSS_COMPILE)ar
495NM		= $(CROSS_COMPILE)nm
496OBJCOPY		= $(CROSS_COMPILE)objcopy
497OBJDUMP		= $(CROSS_COMPILE)objdump
498READELF		= $(CROSS_COMPILE)readelf
499STRIP		= $(CROSS_COMPILE)strip
500endif
501RUSTC		= rustc
502RUSTDOC		= rustdoc
503RUSTFMT		= rustfmt
504CLIPPY_DRIVER	= clippy-driver
505BINDGEN		= bindgen
506CARGO		= cargo
507PAHOLE		= pahole
508RESOLVE_BTFIDS	= $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
509LEX		= flex
510YACC		= bison
511AWK		= awk
512INSTALLKERNEL  := installkernel
513PERL		= perl
514PYTHON3		= python3
515CHECK		= sparse
516BASH		= bash
517KGZIP		= gzip
518KBZIP2		= bzip2
519KLZOP		= lzop
520LZMA		= lzma
521LZ4		= lz4c
522XZ		= xz
523ZSTD		= zstd
524
525PAHOLE_FLAGS	= $(shell PAHOLE=$(PAHOLE) $(srctree)/scripts/pahole-flags.sh)
526
527CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
528		  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
529NOSTDINC_FLAGS :=
530CFLAGS_MODULE   =
531RUSTFLAGS_MODULE =
532AFLAGS_MODULE   =
533LDFLAGS_MODULE  =
534CFLAGS_KERNEL	=
535RUSTFLAGS_KERNEL =
536AFLAGS_KERNEL	=
537LDFLAGS_vmlinux =
538
539# Use USERINCLUDE when you must reference the UAPI directories only.
540USERINCLUDE    := \
541		-I$(srctree)/arch/$(SRCARCH)/include/uapi \
542		-I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
543		-I$(srctree)/include/uapi \
544		-I$(objtree)/include/generated/uapi \
545                -include $(srctree)/include/linux/compiler-version.h \
546                -include $(srctree)/include/linux/kconfig.h
547
548# Use LINUXINCLUDE when you must reference the include/ directory.
549# Needed to be compatible with the O= option
550LINUXINCLUDE    := \
551		-I$(srctree)/arch/$(SRCARCH)/include \
552		-I$(objtree)/arch/$(SRCARCH)/include/generated \
553		$(if $(building_out_of_srctree),-I$(srctree)/include) \
554		-I$(objtree)/include \
555		$(USERINCLUDE)
556
557KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
558
559KBUILD_CFLAGS :=
560KBUILD_CFLAGS += -std=gnu11
561KBUILD_CFLAGS += -fshort-wchar
562KBUILD_CFLAGS += -funsigned-char
563KBUILD_CFLAGS += -fno-common
564KBUILD_CFLAGS += -fno-PIE
565KBUILD_CFLAGS += -fno-strict-aliasing
566
567KBUILD_CPPFLAGS := -D__KERNEL__
568KBUILD_RUSTFLAGS := $(rust_common_flags) \
569		    --target=$(objtree)/scripts/target.json \
570		    -Cpanic=abort -Cembed-bitcode=n -Clto=n \
571		    -Cforce-unwind-tables=n -Ccodegen-units=1 \
572		    -Csymbol-mangling-version=v0 \
573		    -Crelocation-model=static \
574		    -Zfunction-sections=n \
575		    -Dclippy::float_arithmetic
576
577KBUILD_AFLAGS_KERNEL :=
578KBUILD_CFLAGS_KERNEL :=
579KBUILD_RUSTFLAGS_KERNEL :=
580KBUILD_AFLAGS_MODULE  := -DMODULE
581KBUILD_CFLAGS_MODULE  := -DMODULE
582KBUILD_RUSTFLAGS_MODULE := --cfg MODULE
583KBUILD_LDFLAGS_MODULE :=
584KBUILD_LDFLAGS :=
585CLANG_FLAGS :=
586
587ifeq ($(KBUILD_CLIPPY),1)
588	RUSTC_OR_CLIPPY_QUIET := CLIPPY
589	RUSTC_OR_CLIPPY = $(CLIPPY_DRIVER)
590else
591	RUSTC_OR_CLIPPY_QUIET := RUSTC
592	RUSTC_OR_CLIPPY = $(RUSTC)
593endif
594
595ifdef RUST_LIB_SRC
596	export RUST_LIB_SRC
597endif
598
599# Allows the usage of unstable features in stable compilers.
600export RUSTC_BOOTSTRAP := 1
601
602export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG
603export RUSTC RUSTDOC RUSTFMT RUSTC_OR_CLIPPY_QUIET RUSTC_OR_CLIPPY BINDGEN CARGO
604export HOSTRUSTC KBUILD_HOSTRUSTFLAGS
605export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
606export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
607export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
608export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
609export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS
610
611export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
612export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
613export KBUILD_RUSTFLAGS RUSTFLAGS_KERNEL RUSTFLAGS_MODULE
614export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
615export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_RUSTFLAGS_MODULE KBUILD_LDFLAGS_MODULE
616export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL KBUILD_RUSTFLAGS_KERNEL
617export PAHOLE_FLAGS
618
619# Files to ignore in find ... statements
620
621export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
622			  -name CVS -o -name .pc -o -name .hg -o -name .git \) \
623			  -prune -o
624export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
625			 --exclude CVS --exclude .pc --exclude .hg --exclude .git
626
627# ===========================================================================
628# Rules shared between *config targets and build targets
629
630# Basic helpers built in scripts/basic/
631PHONY += scripts_basic
632scripts_basic:
633	$(Q)$(MAKE) $(build)=scripts/basic
634
635PHONY += outputmakefile
636ifdef building_out_of_srctree
637# Before starting out-of-tree build, make sure the source tree is clean.
638# outputmakefile generates a Makefile in the output directory, if using a
639# separate output directory. This allows convenient use of make in the
640# output directory.
641# At the same time when output Makefile generated, generate .gitignore to
642# ignore whole output directory
643
644quiet_cmd_makefile = GEN     Makefile
645      cmd_makefile = { \
646	echo "\# Automatically generated by $(srctree)/Makefile: don't edit"; \
647	echo "include $(srctree)/Makefile"; \
648	} > Makefile
649
650outputmakefile:
651	@if [ -f $(srctree)/.config -o \
652		 -d $(srctree)/include/config -o \
653		 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
654		echo >&2 "***"; \
655		echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
656		echo >&2 "*** in $(abs_srctree)";\
657		echo >&2 "***"; \
658		false; \
659	fi
660	$(Q)ln -fsn $(srctree) source
661	$(call cmd,makefile)
662	$(Q)test -e .gitignore || \
663	{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
664endif
665
666# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
667# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
668# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
669# and from include/config/auto.conf.cmd to detect the compiler upgrade.
670CC_VERSION_TEXT = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1))
671
672ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
673include $(srctree)/scripts/Makefile.clang
674endif
675
676# Include this also for config targets because some architectures need
677# cc-cross-prefix to determine CROSS_COMPILE.
678ifdef need-compiler
679include $(srctree)/scripts/Makefile.compiler
680endif
681
682ifdef config-build
683# ===========================================================================
684# *config targets only - make sure prerequisites are updated, and descend
685# in scripts/kconfig to make the *config target
686
687# Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
688# KBUILD_DEFCONFIG may point out an alternative default configuration
689# used for 'make defconfig'
690include $(srctree)/arch/$(SRCARCH)/Makefile
691export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
692
693config: outputmakefile scripts_basic FORCE
694	$(Q)$(MAKE) $(build)=scripts/kconfig $@
695
696%config: outputmakefile scripts_basic FORCE
697	$(Q)$(MAKE) $(build)=scripts/kconfig $@
698
699else #!config-build
700# ===========================================================================
701# Build targets only - this includes vmlinux, arch specific targets, clean
702# targets and others. In general all targets except *config targets.
703
704# If building an external module we do not care about the all: rule
705# but instead __all depend on modules
706PHONY += all
707ifeq ($(KBUILD_EXTMOD),)
708__all: all
709else
710__all: modules
711endif
712
713targets :=
714
715# Decide whether to build built-in, modular, or both.
716# Normally, just do built-in.
717
718KBUILD_MODULES :=
719KBUILD_BUILTIN := 1
720
721# If we have only "make modules", don't compile built-in objects.
722ifeq ($(MAKECMDGOALS),modules)
723  KBUILD_BUILTIN :=
724endif
725
726# If we have "make <whatever> modules", compile modules
727# in addition to whatever we do anyway.
728# Just "make" or "make all" shall build modules as well
729
730ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
731  KBUILD_MODULES := 1
732endif
733
734ifeq ($(MAKECMDGOALS),)
735  KBUILD_MODULES := 1
736endif
737
738export KBUILD_MODULES KBUILD_BUILTIN
739
740ifdef need-config
741include include/config/auto.conf
742endif
743
744ifeq ($(KBUILD_EXTMOD),)
745# Objects we will link into vmlinux / subdirs we need to visit
746core-y		:=
747drivers-y	:=
748libs-y		:= lib/
749endif # KBUILD_EXTMOD
750
751# The all: target is the default when no target is given on the
752# command line.
753# This allow a user to issue only 'make' to build a kernel including modules
754# Defaults to vmlinux, but the arch makefile usually adds further targets
755all: vmlinux
756
757CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage
758ifdef CONFIG_CC_IS_GCC
759CFLAGS_GCOV	+= -fno-tree-loop-im
760endif
761export CFLAGS_GCOV
762
763# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
764ifdef CONFIG_FUNCTION_TRACER
765  CC_FLAGS_FTRACE := -pg
766endif
767
768include $(srctree)/arch/$(SRCARCH)/Makefile
769
770ifdef need-config
771ifdef may-sync-config
772# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
773# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
774# because some architectures define CROSS_COMPILE there.
775include include/config/auto.conf.cmd
776
777$(KCONFIG_CONFIG):
778	@echo >&2 '***'
779	@echo >&2 '*** Configuration file "$@" not found!'
780	@echo >&2 '***'
781	@echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
782	@echo >&2 '*** "make menuconfig" or "make xconfig").'
783	@echo >&2 '***'
784	@/bin/false
785
786# The actual configuration files used during the build are stored in
787# include/generated/ and include/config/. Update them if .config is newer than
788# include/config/auto.conf (which mirrors .config).
789#
790# This exploits the 'multi-target pattern rule' trick.
791# The syncconfig should be executed only once to make all the targets.
792# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
793#
794# Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
795# so you cannot notice that Kconfig is waiting for the user input.
796%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h %/generated/rustc_cfg: $(KCONFIG_CONFIG)
797	$(Q)$(kecho) "  SYNC    $@"
798	$(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
799else # !may-sync-config
800# External modules and some install targets need include/generated/autoconf.h
801# and include/config/auto.conf but do not care if they are up-to-date.
802# Use auto.conf to trigger the test
803PHONY += include/config/auto.conf
804
805include/config/auto.conf:
806	@test -e include/generated/autoconf.h -a -e $@ || (		\
807	echo >&2;							\
808	echo >&2 "  ERROR: Kernel configuration is invalid.";		\
809	echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
810	echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";	\
811	echo >&2 ;							\
812	/bin/false)
813
814endif # may-sync-config
815endif # need-config
816
817KBUILD_CFLAGS	+= -fno-delete-null-pointer-checks
818
819ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
820KBUILD_CFLAGS += -O2
821KBUILD_RUSTFLAGS += -Copt-level=2
822else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
823KBUILD_CFLAGS += -Os
824KBUILD_RUSTFLAGS += -Copt-level=s
825endif
826
827# Always set `debug-assertions` and `overflow-checks` because their default
828# depends on `opt-level` and `debug-assertions`, respectively.
829KBUILD_RUSTFLAGS += -Cdebug-assertions=$(if $(CONFIG_RUST_DEBUG_ASSERTIONS),y,n)
830KBUILD_RUSTFLAGS += -Coverflow-checks=$(if $(CONFIG_RUST_OVERFLOW_CHECKS),y,n)
831
832# Tell gcc to never replace conditional load with a non-conditional one
833ifdef CONFIG_CC_IS_GCC
834# gcc-10 renamed --param=allow-store-data-races=0 to
835# -fno-allow-store-data-races.
836KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
837KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
838endif
839
840ifdef CONFIG_READABLE_ASM
841# Disable optimizations that make assembler listings hard to read.
842# reorder blocks reorders the control in the function
843# ipa clone creates specialized cloned functions
844# partial inlining inlines only parts of functions
845KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
846endif
847
848stackp-flags-y                                    := -fno-stack-protector
849stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
850stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
851
852KBUILD_CFLAGS += $(stackp-flags-y)
853
854KBUILD_RUSTFLAGS-$(CONFIG_WERROR) += -Dwarnings
855KBUILD_RUSTFLAGS += $(KBUILD_RUSTFLAGS-y)
856
857ifdef CONFIG_FRAME_POINTER
858KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
859KBUILD_RUSTFLAGS += -Cforce-frame-pointers=y
860else
861# Some targets (ARM with Thumb2, for example), can't be built with frame
862# pointers.  For those, we don't have FUNCTION_TRACER automatically
863# select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
864# incompatible with -fomit-frame-pointer with current GCC, so we don't use
865# -fomit-frame-pointer with FUNCTION_TRACER.
866# In the Rust target specification, "frame-pointer" is set explicitly
867# to "may-omit".
868ifndef CONFIG_FUNCTION_TRACER
869KBUILD_CFLAGS	+= -fomit-frame-pointer
870endif
871endif
872
873# Initialize all stack variables with a 0xAA pattern.
874ifdef CONFIG_INIT_STACK_ALL_PATTERN
875KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
876endif
877
878# Initialize all stack variables with a zero value.
879ifdef CONFIG_INIT_STACK_ALL_ZERO
880KBUILD_CFLAGS	+= -ftrivial-auto-var-init=zero
881ifdef CONFIG_CC_HAS_AUTO_VAR_INIT_ZERO_ENABLER
882# https://github.com/llvm/llvm-project/issues/44842
883CC_AUTO_VAR_INIT_ZERO_ENABLER := -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
884export CC_AUTO_VAR_INIT_ZERO_ENABLER
885KBUILD_CFLAGS	+= $(CC_AUTO_VAR_INIT_ZERO_ENABLER)
886endif
887endif
888
889# While VLAs have been removed, GCC produces unreachable stack probes
890# for the randomize_kstack_offset feature. Disable it for all compilers.
891KBUILD_CFLAGS	+= $(call cc-option, -fno-stack-clash-protection)
892
893# Clear used registers at func exit (to reduce data lifetime and ROP gadgets).
894ifdef CONFIG_ZERO_CALL_USED_REGS
895KBUILD_CFLAGS	+= -fzero-call-used-regs=used-gpr
896endif
897
898ifdef CONFIG_FUNCTION_TRACER
899ifdef CONFIG_FTRACE_MCOUNT_USE_CC
900  CC_FLAGS_FTRACE	+= -mrecord-mcount
901  ifdef CONFIG_HAVE_NOP_MCOUNT
902    ifeq ($(call cc-option-yn, -mnop-mcount),y)
903      CC_FLAGS_FTRACE	+= -mnop-mcount
904      CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
905    endif
906  endif
907endif
908ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
909  ifdef CONFIG_HAVE_OBJTOOL_NOP_MCOUNT
910    CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
911  endif
912endif
913ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
914  ifdef CONFIG_HAVE_C_RECORDMCOUNT
915    BUILD_C_RECORDMCOUNT := y
916    export BUILD_C_RECORDMCOUNT
917  endif
918endif
919ifdef CONFIG_HAVE_FENTRY
920  # s390-linux-gnu-gcc did not support -mfentry until gcc-9.
921  ifeq ($(call cc-option-yn, -mfentry),y)
922    CC_FLAGS_FTRACE	+= -mfentry
923    CC_FLAGS_USING	+= -DCC_USING_FENTRY
924  endif
925endif
926export CC_FLAGS_FTRACE
927KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
928KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
929endif
930
931# We trigger additional mismatches with less inlining
932ifdef CONFIG_DEBUG_SECTION_MISMATCH
933KBUILD_CFLAGS += -fno-inline-functions-called-once
934endif
935
936# `rustc`'s `-Zfunction-sections` applies to data too (as of 1.59.0).
937ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
938KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
939KBUILD_RUSTFLAGS_KERNEL += -Zfunction-sections=y
940LDFLAGS_vmlinux += --gc-sections
941endif
942
943ifdef CONFIG_SHADOW_CALL_STACK
944ifndef CONFIG_DYNAMIC_SCS
945CC_FLAGS_SCS	:= -fsanitize=shadow-call-stack
946KBUILD_CFLAGS	+= $(CC_FLAGS_SCS)
947endif
948export CC_FLAGS_SCS
949endif
950
951ifdef CONFIG_LTO_CLANG
952ifdef CONFIG_LTO_CLANG_THIN
953CC_FLAGS_LTO	:= -flto=thin -fsplit-lto-unit
954KBUILD_LDFLAGS	+= --thinlto-cache-dir=$(extmod_prefix).thinlto-cache
955else
956CC_FLAGS_LTO	:= -flto
957endif
958CC_FLAGS_LTO	+= -fvisibility=hidden
959
960# Limit inlining across translation units to reduce binary size
961KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
962
963# Check for frame size exceeding threshold during prolog/epilog insertion
964# when using lld < 13.0.0.
965ifneq ($(CONFIG_FRAME_WARN),0)
966ifeq ($(call test-lt, $(CONFIG_LLD_VERSION), 130000),y)
967KBUILD_LDFLAGS	+= -plugin-opt=-warn-stack-size=$(CONFIG_FRAME_WARN)
968endif
969endif
970endif
971
972ifdef CONFIG_LTO
973KBUILD_CFLAGS	+= -fno-lto $(CC_FLAGS_LTO)
974KBUILD_AFLAGS	+= -fno-lto
975export CC_FLAGS_LTO
976endif
977
978ifdef CONFIG_CFI_CLANG
979CC_FLAGS_CFI	:= -fsanitize=kcfi
980KBUILD_CFLAGS	+= $(CC_FLAGS_CFI)
981export CC_FLAGS_CFI
982endif
983
984ifneq ($(CONFIG_FUNCTION_ALIGNMENT),0)
985KBUILD_CFLAGS += -falign-functions=$(CONFIG_FUNCTION_ALIGNMENT)
986endif
987
988# arch Makefile may override CC so keep this after arch Makefile is included
989NOSTDINC_FLAGS += -nostdinc
990
991# To gain proper coverage for CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE,
992# the kernel uses only C99 flexible arrays for dynamically sized trailing
993# arrays. Enforce this for everything that may examine structure sizes and
994# perform bounds checking.
995KBUILD_CFLAGS += $(call cc-option, -fstrict-flex-arrays=3)
996
997# disable invalid "can't wrap" optimizations for signed / pointers
998KBUILD_CFLAGS	+= -fno-strict-overflow
999
1000# Make sure -fstack-check isn't enabled (like gentoo apparently did)
1001KBUILD_CFLAGS  += -fno-stack-check
1002
1003# conserve stack if available
1004ifdef CONFIG_CC_IS_GCC
1005KBUILD_CFLAGS   += -fconserve-stack
1006endif
1007
1008# change __FILE__ to the relative path from the srctree
1009KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
1010
1011# include additional Makefiles when needed
1012include-y			:= scripts/Makefile.extrawarn
1013include-$(CONFIG_DEBUG_INFO)	+= scripts/Makefile.debug
1014include-$(CONFIG_KASAN)		+= scripts/Makefile.kasan
1015include-$(CONFIG_KCSAN)		+= scripts/Makefile.kcsan
1016include-$(CONFIG_KMSAN)		+= scripts/Makefile.kmsan
1017include-$(CONFIG_UBSAN)		+= scripts/Makefile.ubsan
1018include-$(CONFIG_KCOV)		+= scripts/Makefile.kcov
1019include-$(CONFIG_RANDSTRUCT)	+= scripts/Makefile.randstruct
1020include-$(CONFIG_GCC_PLUGINS)	+= scripts/Makefile.gcc-plugins
1021
1022include $(addprefix $(srctree)/, $(include-y))
1023
1024# scripts/Makefile.gcc-plugins is intentionally included last.
1025# Do not add $(call cc-option,...) below this line. When you build the kernel
1026# from the clean source tree, the GCC plugins do not exist at this point.
1027
1028# Add user supplied CPPFLAGS, AFLAGS, CFLAGS and RUSTFLAGS as the last assignments
1029KBUILD_CPPFLAGS += $(KCPPFLAGS)
1030KBUILD_AFLAGS   += $(KAFLAGS)
1031KBUILD_CFLAGS   += $(KCFLAGS)
1032KBUILD_RUSTFLAGS += $(KRUSTFLAGS)
1033
1034KBUILD_LDFLAGS_MODULE += --build-id=sha1
1035LDFLAGS_vmlinux += --build-id=sha1
1036
1037KBUILD_LDFLAGS	+= -z noexecstack
1038ifeq ($(CONFIG_LD_IS_BFD),y)
1039KBUILD_LDFLAGS	+= $(call ld-option,--no-warn-rwx-segments)
1040endif
1041
1042ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1043LDFLAGS_vmlinux	+= -X
1044endif
1045
1046ifeq ($(CONFIG_RELR),y)
1047# ld.lld before 15 did not support -z pack-relative-relocs.
1048LDFLAGS_vmlinux	+= $(call ld-option,--pack-dyn-relocs=relr,-z pack-relative-relocs)
1049endif
1050
1051# We never want expected sections to be placed heuristically by the
1052# linker. All sections should be explicitly named in the linker script.
1053ifdef CONFIG_LD_ORPHAN_WARN
1054LDFLAGS_vmlinux += --orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL)
1055endif
1056
1057# Align the bit size of userspace programs with the kernel
1058KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1059KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1060
1061# make the checker run with the right architecture
1062CHECKFLAGS += --arch=$(ARCH)
1063
1064# insure the checker run with the right endianness
1065CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1066
1067# the checker needs the correct machine size
1068CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1069
1070# Default kernel image to build when no specific target is given.
1071# KBUILD_IMAGE may be overruled on the command line or
1072# set in the environment
1073# Also any assignments in arch/$(ARCH)/Makefile take precedence over
1074# this default value
1075export KBUILD_IMAGE ?= vmlinux
1076
1077#
1078# INSTALL_PATH specifies where to place the updated kernel and system map
1079# images. Default is /boot, but you can set it to other values
1080export	INSTALL_PATH ?= /boot
1081
1082#
1083# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1084# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1085# an argument if needed. Otherwise it defaults to the kernel install path
1086#
1087export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1088
1089#
1090# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1091# relocations required by build roots.  This is not defined in the
1092# makefile but the argument can be passed to make if needed.
1093#
1094
1095MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1096export MODLIB
1097
1098PHONY += prepare0
1099
1100export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
1101export MODORDER := $(extmod_prefix)modules.order
1102export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
1103
1104ifeq ($(KBUILD_EXTMOD),)
1105
1106build-dir	:= .
1107clean-dirs	:= $(sort . Documentation \
1108		     $(patsubst %/,%,$(filter %/, $(core-) \
1109			$(drivers-) $(libs-))))
1110
1111export ARCH_CORE	:= $(core-y)
1112export ARCH_LIB		:= $(filter %/, $(libs-y))
1113export ARCH_DRIVERS	:= $(drivers-y) $(drivers-m)
1114# Externally visible symbols (used by link-vmlinux.sh)
1115
1116KBUILD_VMLINUX_OBJS := ./built-in.a
1117ifdef CONFIG_MODULES
1118KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1119KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1120else
1121KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1122endif
1123
1124export KBUILD_VMLINUX_LIBS
1125export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1126
1127ifdef CONFIG_TRIM_UNUSED_KSYMS
1128# For the kernel to actually contain only the needed exported symbols,
1129# we have to build modules as well to determine what those symbols are.
1130KBUILD_MODULES := 1
1131endif
1132
1133# '$(AR) mPi' needs 'T' to workaround the bug of llvm-ar <= 14
1134quiet_cmd_ar_vmlinux.a = AR      $@
1135      cmd_ar_vmlinux.a = \
1136	rm -f $@; \
1137	$(AR) cDPrST $@ $(KBUILD_VMLINUX_OBJS); \
1138	$(AR) mPiT $$($(AR) t $@ | sed -n 1p) $@ $$($(AR) t $@ | grep -F -f $(srctree)/scripts/head-object-list.txt)
1139
1140targets += vmlinux.a
1141vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt FORCE
1142	$(call if_changed,ar_vmlinux.a)
1143
1144PHONY += vmlinux_o
1145vmlinux_o: vmlinux.a $(KBUILD_VMLINUX_LIBS)
1146	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o
1147
1148vmlinux.o modules.builtin.modinfo modules.builtin: vmlinux_o
1149	@:
1150
1151PHONY += vmlinux
1152# LDFLAGS_vmlinux in the top Makefile defines linker flags for the top vmlinux,
1153# not for decompressors. LDFLAGS_vmlinux in arch/*/boot/compressed/Makefile is
1154# unrelated; the decompressors just happen to have the same base name,
1155# arch/*/boot/compressed/vmlinux.
1156# Export LDFLAGS_vmlinux only to scripts/Makefile.vmlinux.
1157#
1158# _LDFLAGS_vmlinux is a workaround for the 'private export' bug:
1159#   https://savannah.gnu.org/bugs/?61463
1160# For Make > 4.4, the following simple code will work:
1161#  vmlinux: private export LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1162vmlinux: private _LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1163vmlinux: export LDFLAGS_vmlinux = $(_LDFLAGS_vmlinux)
1164vmlinux: vmlinux.o $(KBUILD_LDS) modpost
1165	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux
1166
1167# The actual objects are generated when descending,
1168# make sure no implicit rule kicks in
1169$(sort $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)): . ;
1170
1171ifeq ($(origin KERNELRELEASE),file)
1172filechk_kernel.release = $(srctree)/scripts/setlocalversion $(srctree)
1173else
1174filechk_kernel.release = echo $(KERNELRELEASE)
1175endif
1176
1177# Store (new) KERNELRELEASE string in include/config/kernel.release
1178include/config/kernel.release: FORCE
1179	$(call filechk,kernel.release)
1180
1181# Additional helpers built in scripts/
1182# Carefully list dependencies so we do not try to build scripts twice
1183# in parallel
1184PHONY += scripts
1185scripts: scripts_basic scripts_dtc
1186	$(Q)$(MAKE) $(build)=$(@)
1187
1188# Things we need to do before we recursively start building the kernel
1189# or the modules are listed in "prepare".
1190# A multi level approach is used. prepareN is processed before prepareN-1.
1191# archprepare is used in arch Makefiles and when processed asm symlink,
1192# version.h and scripts_basic is processed / created.
1193
1194PHONY += prepare archprepare
1195
1196archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1197	asm-generic $(version_h) include/generated/utsrelease.h \
1198	include/generated/compile.h include/generated/autoconf.h remove-stale-files
1199
1200prepare0: archprepare
1201	$(Q)$(MAKE) $(build)=scripts/mod
1202	$(Q)$(MAKE) $(build)=. prepare
1203
1204# All the preparing..
1205prepare: prepare0
1206ifdef CONFIG_RUST
1207	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh
1208	$(Q)$(MAKE) $(build)=rust
1209endif
1210
1211PHONY += remove-stale-files
1212remove-stale-files:
1213	$(Q)$(srctree)/scripts/remove-stale-files
1214
1215# Support for using generic headers in asm-generic
1216asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1217
1218PHONY += asm-generic uapi-asm-generic
1219asm-generic: uapi-asm-generic
1220	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1221	generic=include/asm-generic
1222uapi-asm-generic:
1223	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1224	generic=include/uapi/asm-generic
1225
1226# Generate some files
1227# ---------------------------------------------------------------------------
1228
1229# KERNELRELEASE can change from a few different places, meaning version.h
1230# needs to be updated, so this check is forced on all builds
1231
1232uts_len := 64
1233define filechk_utsrelease.h
1234	if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1235	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1236	  exit 1;                                                         \
1237	fi;                                                               \
1238	echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1239endef
1240
1241define filechk_version.h
1242	if [ $(SUBLEVEL) -gt 255 ]; then                                 \
1243		echo \#define LINUX_VERSION_CODE $(shell                 \
1244		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1245	else                                                             \
1246		echo \#define LINUX_VERSION_CODE $(shell                 \
1247		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1248	fi;                                                              \
1249	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
1250	((c) > 255 ? 255 : (c)))';                                       \
1251	echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
1252	echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
1253	echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1254endef
1255
1256$(version_h): PATCHLEVEL := $(or $(PATCHLEVEL), 0)
1257$(version_h): SUBLEVEL := $(or $(SUBLEVEL), 0)
1258$(version_h): FORCE
1259	$(call filechk,version.h)
1260
1261include/generated/utsrelease.h: include/config/kernel.release FORCE
1262	$(call filechk,utsrelease.h)
1263
1264filechk_compile.h = $(srctree)/scripts/mkcompile_h \
1265	"$(UTS_MACHINE)" "$(CONFIG_CC_VERSION_TEXT)" "$(LD)"
1266
1267include/generated/compile.h: FORCE
1268	$(call filechk,compile.h)
1269
1270PHONY += headerdep
1271headerdep:
1272	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1273	$(srctree)/scripts/headerdep.pl -I$(srctree)/include
1274
1275# ---------------------------------------------------------------------------
1276# Kernel headers
1277
1278#Default location for installed headers
1279export INSTALL_HDR_PATH = $(objtree)/usr
1280
1281quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1282      cmd_headers_install = \
1283	mkdir -p $(INSTALL_HDR_PATH); \
1284	rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1285	usr/include $(INSTALL_HDR_PATH)
1286
1287PHONY += headers_install
1288headers_install: headers
1289	$(call cmd,headers_install)
1290
1291PHONY += archheaders archscripts
1292
1293hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1294
1295PHONY += headers
1296headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1297	$(if $(filter um, $(SRCARCH)), $(error Headers not exportable for UML))
1298	$(Q)$(MAKE) $(hdr-inst)=include/uapi
1299	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1300
1301ifdef CONFIG_HEADERS_INSTALL
1302prepare: headers
1303endif
1304
1305PHONY += scripts_unifdef
1306scripts_unifdef: scripts_basic
1307	$(Q)$(MAKE) $(build)=scripts scripts/unifdef
1308
1309# ---------------------------------------------------------------------------
1310# Install
1311
1312# Many distributions have the custom install script, /sbin/installkernel.
1313# If DKMS is installed, 'make install' will eventually recurse back
1314# to this Makefile to build and install external modules.
1315# Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
1316
1317quiet_cmd_install = INSTALL $(INSTALL_PATH)
1318      cmd_install = unset sub_make_done; $(srctree)/scripts/install.sh
1319
1320# ---------------------------------------------------------------------------
1321# Tools
1322
1323ifdef CONFIG_OBJTOOL
1324prepare: tools/objtool
1325endif
1326
1327ifdef CONFIG_BPF
1328ifdef CONFIG_DEBUG_INFO_BTF
1329prepare: tools/bpf/resolve_btfids
1330endif
1331endif
1332
1333PHONY += resolve_btfids_clean
1334
1335resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1336
1337# tools/bpf/resolve_btfids directory might not exist
1338# in output directory, skip its clean in that case
1339resolve_btfids_clean:
1340ifneq ($(wildcard $(resolve_btfids_O)),)
1341	$(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1342endif
1343
1344# Clear a bunch of variables before executing the submake
1345ifeq ($(quiet),silent_)
1346tools_silent=s
1347endif
1348
1349tools/: FORCE
1350	$(Q)mkdir -p $(objtree)/tools
1351	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1352
1353tools/%: FORCE
1354	$(Q)mkdir -p $(objtree)/tools
1355	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1356
1357# ---------------------------------------------------------------------------
1358# Kernel selftest
1359
1360PHONY += kselftest
1361kselftest: headers
1362	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1363
1364kselftest-%: headers FORCE
1365	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1366
1367PHONY += kselftest-merge
1368kselftest-merge:
1369	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1370	$(Q)find $(srctree)/tools/testing/selftests -name config | \
1371		xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1372	$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1373
1374# ---------------------------------------------------------------------------
1375# Devicetree files
1376
1377ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1378dtstree := arch/$(SRCARCH)/boot/dts
1379endif
1380
1381ifneq ($(dtstree),)
1382
1383%.dtb: dtbs_prepare
1384	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1385
1386%.dtbo: dtbs_prepare
1387	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1388
1389PHONY += dtbs dtbs_prepare dtbs_install dtbs_check
1390dtbs: dtbs_prepare
1391	$(Q)$(MAKE) $(build)=$(dtstree)
1392
1393# include/config/kernel.release is actually needed when installing DTBs because
1394# INSTALL_DTBS_PATH contains $(KERNELRELEASE). However, we do not want to make
1395# dtbs_install depend on it as dtbs_install may run as root.
1396dtbs_prepare: include/config/kernel.release scripts_dtc
1397
1398ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1399export CHECK_DTBS=y
1400endif
1401
1402ifneq ($(CHECK_DTBS),)
1403dtbs_prepare: dt_binding_check
1404endif
1405
1406dtbs_check: dtbs
1407
1408dtbs_install:
1409	$(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1410
1411ifdef CONFIG_OF_EARLY_FLATTREE
1412all: dtbs
1413endif
1414
1415endif
1416
1417PHONY += scripts_dtc
1418scripts_dtc: scripts_basic
1419	$(Q)$(MAKE) $(build)=scripts/dtc
1420
1421ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1422export CHECK_DT_BINDING=y
1423endif
1424
1425PHONY += dt_binding_check
1426dt_binding_check: scripts_dtc
1427	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1428
1429PHONY += dt_compatible_check
1430dt_compatible_check: dt_binding_check
1431	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1432
1433# ---------------------------------------------------------------------------
1434# Modules
1435
1436ifdef CONFIG_MODULES
1437
1438# By default, build modules as well
1439
1440all: modules
1441
1442# When we're building modules with modversions, we need to consider
1443# the built-in objects during the descend as well, in order to
1444# make sure the checksums are up to date before we record them.
1445ifdef CONFIG_MODVERSIONS
1446  KBUILD_BUILTIN := 1
1447endif
1448
1449# Build modules
1450#
1451
1452# *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFO_BTF_MODULES
1453# is an exception.
1454ifdef CONFIG_DEBUG_INFO_BTF_MODULES
1455KBUILD_BUILTIN := 1
1456modules: vmlinux
1457endif
1458
1459modules: modules_prepare
1460
1461# Target to prepare building external modules
1462modules_prepare: prepare
1463	$(Q)$(MAKE) $(build)=scripts scripts/module.lds
1464
1465endif # CONFIG_MODULES
1466
1467###
1468# Cleaning is done on three levels.
1469# make clean     Delete most generated files
1470#                Leave enough to build external modules
1471# make mrproper  Delete the current configuration, and all generated files
1472# make distclean Remove editor backup files, patch leftover files and the like
1473
1474# Directories & files removed with 'make clean'
1475CLEAN_FILES += vmlinux.symvers modules-only.symvers \
1476	       modules.builtin modules.builtin.modinfo modules.nsdeps \
1477	       compile_commands.json .thinlto-cache rust/test \
1478	       rust-project.json .vmlinux.objs .vmlinux.export.c
1479
1480# Directories & files removed with 'make mrproper'
1481MRPROPER_FILES += include/config include/generated          \
1482		  arch/$(SRCARCH)/include/generated .objdiff \
1483		  debian snap tar-install \
1484		  .config .config.old .version \
1485		  Module.symvers \
1486		  certs/signing_key.pem \
1487		  certs/x509.genkey \
1488		  vmlinux-gdb.py \
1489		  kernel.spec rpmbuild \
1490		  rust/libmacros.so
1491
1492# clean - Delete most, but leave enough to build external modules
1493#
1494clean: rm-files := $(CLEAN_FILES)
1495
1496PHONY += archclean vmlinuxclean
1497
1498vmlinuxclean:
1499	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1500	$(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1501
1502clean: archclean vmlinuxclean resolve_btfids_clean
1503
1504# mrproper - Delete all generated files, including .config
1505#
1506mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1507mrproper-dirs      := $(addprefix _mrproper_,scripts)
1508
1509PHONY += $(mrproper-dirs) mrproper
1510$(mrproper-dirs):
1511	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1512
1513mrproper: clean $(mrproper-dirs)
1514	$(call cmd,rmfiles)
1515	@find . $(RCS_FIND_IGNORE) \
1516		\( -name '*.rmeta' \) \
1517		-type f -print | xargs rm -f
1518
1519# distclean
1520#
1521PHONY += distclean
1522
1523distclean: mrproper
1524	@find . $(RCS_FIND_IGNORE) \
1525		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1526		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
1527		-o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1528		-o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1529		-type f -print | xargs rm -f
1530
1531
1532# Packaging of the kernel to various formats
1533# ---------------------------------------------------------------------------
1534
1535%src-pkg: FORCE
1536	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1537%pkg: include/config/kernel.release FORCE
1538	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1539
1540# Brief documentation of the typical targets used
1541# ---------------------------------------------------------------------------
1542
1543boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1544boards := $(sort $(notdir $(boards)))
1545board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1546board-dirs := $(sort $(notdir $(board-dirs:/=)))
1547
1548PHONY += help
1549help:
1550	@echo  'Cleaning targets:'
1551	@echo  '  clean		  - Remove most generated files but keep the config and'
1552	@echo  '                    enough build support to build external modules'
1553	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
1554	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
1555	@echo  ''
1556	@$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1557	@echo  ''
1558	@echo  'Other generic targets:'
1559	@echo  '  all		  - Build all targets marked with [*]'
1560	@echo  '* vmlinux	  - Build the bare kernel'
1561	@echo  '* modules	  - Build all modules'
1562	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1563	@echo  '  dir/            - Build all files in dir and below'
1564	@echo  '  dir/file.[ois]  - Build specified target only'
1565	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1566	@echo  '                    (requires compiler support for LLVM assembly generation)'
1567	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1568	@echo  '                    (requires a recent binutils and recent build (System.map))'
1569	@echo  '  dir/file.ko     - Build module including final link'
1570	@echo  '  modules_prepare - Set up for building external modules'
1571	@echo  '  tags/TAGS	  - Generate tags file for editors'
1572	@echo  '  cscope	  - Generate cscope index'
1573	@echo  '  gtags           - Generate GNU GLOBAL index'
1574	@echo  '  kernelrelease	  - Output the release version string (use with make -s)'
1575	@echo  '  kernelversion	  - Output the version stored in Makefile (use with make -s)'
1576	@echo  '  image_name	  - Output the image name (use with make -s)'
1577	@echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1578	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1579	 echo  ''
1580	@echo  'Static analysers:'
1581	@echo  '  checkstack      - Generate a list of stack hogs'
1582	@echo  '  versioncheck    - Sanity check on version.h usage'
1583	@echo  '  includecheck    - Check for duplicate included header files'
1584	@echo  '  export_report   - List the usages of all exported symbols'
1585	@echo  '  headerdep       - Detect inclusion cycles in headers'
1586	@echo  '  coccicheck      - Check with Coccinelle'
1587	@echo  '  clang-analyzer  - Check with clang static analyzer'
1588	@echo  '  clang-tidy      - Check with clang-tidy'
1589	@echo  ''
1590	@echo  'Tools:'
1591	@echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1592	@echo  ''
1593	@echo  'Kernel selftest:'
1594	@echo  '  kselftest         - Build and run kernel selftest'
1595	@echo  '                      Build, install, and boot kernel before'
1596	@echo  '                      running kselftest on it'
1597	@echo  '                      Run as root for full coverage'
1598	@echo  '  kselftest-all     - Build kernel selftest'
1599	@echo  '  kselftest-install - Build and install kernel selftest'
1600	@echo  '  kselftest-clean   - Remove all generated kselftest files'
1601	@echo  '  kselftest-merge   - Merge all the config dependencies of'
1602	@echo  '		      kselftest to existing .config.'
1603	@echo  ''
1604	@echo  'Rust targets:'
1605	@echo  '  rustavailable   - Checks whether the Rust toolchain is'
1606	@echo  '		    available and, if not, explains why.'
1607	@echo  '  rustfmt	  - Reformat all the Rust code in the kernel'
1608	@echo  '  rustfmtcheck	  - Checks if all the Rust code in the kernel'
1609	@echo  '		    is formatted, printing a diff otherwise.'
1610	@echo  '  rustdoc	  - Generate Rust documentation'
1611	@echo  '		    (requires kernel .config)'
1612	@echo  '  rusttest        - Runs the Rust tests'
1613	@echo  '                    (requires kernel .config; downloads external repos)'
1614	@echo  '  rust-analyzer	  - Generate rust-project.json rust-analyzer support file'
1615	@echo  '		    (requires kernel .config)'
1616	@echo  '  dir/file.[os]   - Build specified target only'
1617	@echo  '  dir/file.rsi    - Build macro expanded source, similar to C preprocessing.'
1618	@echo  '                    Run with RUSTFMT=n to skip reformatting if needed.'
1619	@echo  '                    The output is not intended to be compilable.'
1620	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1621	@echo  ''
1622	@$(if $(dtstree), \
1623		echo 'Devicetree:'; \
1624		echo '* dtbs             - Build device tree blobs for enabled boards'; \
1625		echo '  dtbs_install     - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1626		echo '  dt_binding_check - Validate device tree binding documents'; \
1627		echo '  dtbs_check       - Validate device tree source files';\
1628		echo '')
1629
1630	@echo 'Userspace tools targets:'
1631	@echo '  use "make tools/help"'
1632	@echo '  or  "cd tools; make help"'
1633	@echo  ''
1634	@echo  'Kernel packaging:'
1635	@$(MAKE) -f $(srctree)/scripts/Makefile.package help
1636	@echo  ''
1637	@echo  'Documentation targets:'
1638	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1639	@echo  ''
1640	@echo  'Architecture specific targets ($(SRCARCH)):'
1641	@$(or $(archhelp),\
1642		echo '  No architecture specific help defined for $(SRCARCH)')
1643	@echo  ''
1644	@$(if $(boards), \
1645		$(foreach b, $(boards), \
1646		printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1647		echo '')
1648	@$(if $(board-dirs), \
1649		$(foreach b, $(board-dirs), \
1650		printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1651		printf "  %-16s - Show all of the above\\n" help-boards; \
1652		echo '')
1653
1654	@echo  '  make V=n   [targets] 1: verbose build'
1655	@echo  '                       2: give reason for rebuild of target'
1656	@echo  '                       V=1 and V=2 can be combined with V=12'
1657	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1658	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1659	@echo  '                       (sparse by default)'
1660	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1661	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1662	@echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
1663	@echo  '		1: warnings which may be relevant and do not occur too often'
1664	@echo  '		2: warnings which occur quite often but may still be relevant'
1665	@echo  '		3: more obscure warnings, can most likely be ignored'
1666	@echo  '		e: warnings are being treated as errors'
1667	@echo  '		Multiple levels can be combined with W=12 or W=123'
1668	@$(if $(dtstree), \
1669		echo '  make CHECK_DTBS=1 [targets] Check all generated dtb files against schema'; \
1670		echo '         This can be applied both to "dtbs" and to individual "foo.dtb" targets' ; \
1671		)
1672	@echo  ''
1673	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
1674	@echo  'For further info see the ./README file'
1675
1676
1677help-board-dirs := $(addprefix help-,$(board-dirs))
1678
1679help-boards: $(help-board-dirs)
1680
1681boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1682
1683$(help-board-dirs): help-%:
1684	@echo  'Architecture specific targets ($(SRCARCH) $*):'
1685	@$(if $(boards-per-dir), \
1686		$(foreach b, $(boards-per-dir), \
1687		printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1688		echo '')
1689
1690
1691# Documentation targets
1692# ---------------------------------------------------------------------------
1693DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1694	       linkcheckdocs dochelp refcheckdocs texinfodocs infodocs
1695PHONY += $(DOC_TARGETS)
1696$(DOC_TARGETS):
1697	$(Q)$(MAKE) $(build)=Documentation $@
1698
1699
1700# Rust targets
1701# ---------------------------------------------------------------------------
1702
1703# "Is Rust available?" target
1704PHONY += rustavailable
1705rustavailable:
1706	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh && echo "Rust is available!"
1707
1708# Documentation target
1709#
1710# Using the singular to avoid running afoul of `no-dot-config-targets`.
1711PHONY += rustdoc
1712rustdoc: prepare
1713	$(Q)$(MAKE) $(build)=rust $@
1714
1715# Testing target
1716PHONY += rusttest
1717rusttest: prepare
1718	$(Q)$(MAKE) $(build)=rust $@
1719
1720# Formatting targets
1721PHONY += rustfmt rustfmtcheck
1722
1723# We skip `rust/alloc` since we want to minimize the diff w.r.t. upstream.
1724#
1725# We match using absolute paths since `find` does not resolve them
1726# when matching, which is a problem when e.g. `srctree` is `..`.
1727# We `grep` afterwards in order to remove the directory entry itself.
1728rustfmt:
1729	$(Q)find $(abs_srctree) -type f -name '*.rs' \
1730		-o -path $(abs_srctree)/rust/alloc -prune \
1731		-o -path $(abs_objtree)/rust/test -prune \
1732		| grep -Fv $(abs_srctree)/rust/alloc \
1733		| grep -Fv $(abs_objtree)/rust/test \
1734		| grep -Fv generated \
1735		| xargs $(RUSTFMT) $(rustfmt_flags)
1736
1737rustfmtcheck: rustfmt_flags = --check
1738rustfmtcheck: rustfmt
1739
1740# Misc
1741# ---------------------------------------------------------------------------
1742
1743PHONY += misc-check
1744misc-check:
1745	$(Q)$(srctree)/scripts/misc-check
1746
1747all: misc-check
1748
1749PHONY += scripts_gdb
1750scripts_gdb: prepare0
1751	$(Q)$(MAKE) $(build)=scripts/gdb
1752	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1753
1754ifdef CONFIG_GDB_SCRIPTS
1755all: scripts_gdb
1756endif
1757
1758else # KBUILD_EXTMOD
1759
1760filechk_kernel.release = echo $(KERNELRELEASE)
1761
1762###
1763# External module support.
1764# When building external modules the kernel used as basis is considered
1765# read-only, and no consistency checks are made and the make
1766# system is not used on the basis kernel. If updates are required
1767# in the basis kernel ordinary make commands (without M=...) must be used.
1768
1769# We are always building only modules.
1770KBUILD_BUILTIN :=
1771KBUILD_MODULES := 1
1772
1773build-dir := $(KBUILD_EXTMOD)
1774
1775compile_commands.json: $(extmod_prefix)compile_commands.json
1776PHONY += compile_commands.json
1777
1778clean-dirs := $(KBUILD_EXTMOD)
1779clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1780	$(KBUILD_EXTMOD)/compile_commands.json $(KBUILD_EXTMOD)/.thinlto-cache
1781
1782PHONY += prepare
1783# now expand this into a simple variable to reduce the cost of shell evaluations
1784prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT)
1785prepare:
1786	@if [ "$(CC_VERSION_TEXT)" != "$(CONFIG_CC_VERSION_TEXT)" ]; then \
1787		echo >&2 "warning: the compiler differs from the one used to build the kernel"; \
1788		echo >&2 "  The kernel was built by: $(CONFIG_CC_VERSION_TEXT)"; \
1789		echo >&2 "  You are using:           $(CC_VERSION_TEXT)"; \
1790	fi
1791
1792PHONY += help
1793help:
1794	@echo  '  Building external modules.'
1795	@echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1796	@echo  ''
1797	@echo  '  modules         - default target, build the module(s)'
1798	@echo  '  modules_install - install the module'
1799	@echo  '  clean           - remove generated files in module directory only'
1800	@echo  '  rust-analyzer	  - generate rust-project.json rust-analyzer support file'
1801	@echo  ''
1802
1803ifndef CONFIG_MODULES
1804modules modules_install: __external_modules_error
1805__external_modules_error:
1806	@echo >&2 '***'
1807	@echo >&2 '*** The present kernel disabled CONFIG_MODULES.'
1808	@echo >&2 '*** You cannot build or install external modules.'
1809	@echo >&2 '***'
1810	@false
1811endif
1812
1813endif # KBUILD_EXTMOD
1814
1815# ---------------------------------------------------------------------------
1816# Modules
1817
1818PHONY += modules modules_install modules_sign modules_prepare
1819
1820modules_install:
1821	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst \
1822	sign-only=$(if $(filter modules_install,$(MAKECMDGOALS)),,y)
1823
1824ifeq ($(CONFIG_MODULE_SIG),y)
1825# modules_sign is a subset of modules_install.
1826# 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1827modules_sign: modules_install
1828	@:
1829else
1830modules_sign:
1831	@echo >&2 '***'
1832	@echo >&2 '*** CONFIG_MODULE_SIG is disabled. You cannot sign modules.'
1833	@echo >&2 '***'
1834	@false
1835endif
1836
1837ifdef CONFIG_MODULES
1838
1839$(MODORDER): $(build-dir)
1840	@:
1841
1842# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
1843# This is solely useful to speed up test compiles.
1844modules: modpost
1845ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1846	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1847endif
1848
1849PHONY += modules_check
1850modules_check: $(MODORDER)
1851	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1852
1853else # CONFIG_MODULES
1854
1855modules:
1856	@:
1857
1858KBUILD_MODULES :=
1859
1860endif # CONFIG_MODULES
1861
1862PHONY += modpost
1863modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \
1864	 $(if $(KBUILD_MODULES), modules_check)
1865	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1866
1867# Single targets
1868# ---------------------------------------------------------------------------
1869# To build individual files in subdirectories, you can do like this:
1870#
1871#   make foo/bar/baz.s
1872#
1873# The supported suffixes for single-target are listed in 'single-targets'
1874#
1875# To build only under specific subdirectories, you can do like this:
1876#
1877#   make foo/bar/baz/
1878
1879ifdef single-build
1880
1881# .ko is special because modpost is needed
1882single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1883single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \
1884		$(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko)))
1885
1886$(single-ko): single_modules
1887	@:
1888$(single-no-ko): $(build-dir)
1889	@:
1890
1891# Remove MODORDER when done because it is not the real one.
1892PHONY += single_modules
1893single_modules: $(single-no-ko) modules_prepare
1894	$(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$(m:%.ko=%.o);) } > $(MODORDER)
1895	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1896ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1897	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1898endif
1899	$(Q)rm -f $(MODORDER)
1900
1901single-goals := $(addprefix $(build-dir)/, $(single-no-ko))
1902
1903KBUILD_MODULES := 1
1904
1905endif
1906
1907# Preset locale variables to speed up the build process. Limit locale
1908# tweaks to this spot to avoid wrong language settings when running
1909# make menuconfig etc.
1910# Error messages still appears in the original language
1911PHONY += $(build-dir)
1912$(build-dir): prepare
1913	$(Q)$(MAKE) $(build)=$@ need-builtin=1 need-modorder=1 $(single-goals)
1914
1915clean-dirs := $(addprefix _clean_, $(clean-dirs))
1916PHONY += $(clean-dirs) clean
1917$(clean-dirs):
1918	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1919
1920clean: $(clean-dirs)
1921	$(call cmd,rmfiles)
1922	@find $(or $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1923		\( -name '*.[aios]' -o -name '*.rsi' -o -name '*.ko' -o -name '.*.cmd' \
1924		-o -name '*.ko.*' \
1925		-o -name '*.dtb' -o -name '*.dtbo' \
1926		-o -name '*.dtb.S' -o -name '*.dtbo.S' \
1927		-o -name '*.dt.yaml' \
1928		-o -name '*.dwo' -o -name '*.lst' \
1929		-o -name '*.su' -o -name '*.mod' \
1930		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1931		-o -name '*.lex.c' -o -name '*.tab.[ch]' \
1932		-o -name '*.asn1.[ch]' \
1933		-o -name '*.symtypes' -o -name 'modules.order' \
1934		-o -name '*.c.[012]*.*' \
1935		-o -name '*.ll' \
1936		-o -name '*.gcno' \
1937		-o -name '*.*.symversions' \) -type f -print \
1938		-o -name '.tmp_*' -print \
1939		| xargs rm -rf
1940
1941# Generate tags for editors
1942# ---------------------------------------------------------------------------
1943quiet_cmd_tags = GEN     $@
1944      cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1945
1946tags TAGS cscope gtags: FORCE
1947	$(call cmd,tags)
1948
1949# IDE support targets
1950PHONY += rust-analyzer
1951rust-analyzer:
1952	$(Q)$(MAKE) $(build)=rust $@
1953
1954# Script to generate missing namespace dependencies
1955# ---------------------------------------------------------------------------
1956
1957PHONY += nsdeps
1958nsdeps: export KBUILD_NSDEPS=1
1959nsdeps: modules
1960	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1961
1962# Clang Tooling
1963# ---------------------------------------------------------------------------
1964
1965quiet_cmd_gen_compile_commands = GEN     $@
1966      cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
1967
1968$(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
1969	$(if $(KBUILD_EXTMOD),, vmlinux.a $(KBUILD_VMLINUX_LIBS)) \
1970	$(if $(CONFIG_MODULES), $(MODORDER)) FORCE
1971	$(call if_changed,gen_compile_commands)
1972
1973targets += $(extmod_prefix)compile_commands.json
1974
1975PHONY += clang-tidy clang-analyzer
1976
1977ifdef CONFIG_CC_IS_CLANG
1978quiet_cmd_clang_tools = CHECK   $<
1979      cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
1980
1981clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
1982	$(call cmd,clang_tools)
1983else
1984clang-tidy clang-analyzer:
1985	@echo "$@ requires CC=clang" >&2
1986	@false
1987endif
1988
1989# Scripts to check various things for consistency
1990# ---------------------------------------------------------------------------
1991
1992PHONY += includecheck versioncheck coccicheck export_report
1993
1994includecheck:
1995	find $(srctree)/* $(RCS_FIND_IGNORE) \
1996		-name '*.[hcS]' -type f -print | sort \
1997		| xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1998
1999versioncheck:
2000	find $(srctree)/* $(RCS_FIND_IGNORE) \
2001		-name '*.[hcS]' -type f -print | sort \
2002		| xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
2003
2004coccicheck:
2005	$(Q)$(BASH) $(srctree)/scripts/$@
2006
2007export_report:
2008	$(PERL) $(srctree)/scripts/export_report.pl
2009
2010PHONY += checkstack kernelrelease kernelversion image_name
2011
2012# UML needs a little special treatment here.  It wants to use the host
2013# toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
2014# else wants $(ARCH), including people doing cross-builds, which means
2015# that $(SUBARCH) doesn't work here.
2016ifeq ($(ARCH), um)
2017CHECKSTACK_ARCH := $(SUBARCH)
2018else
2019CHECKSTACK_ARCH := $(ARCH)
2020endif
2021checkstack:
2022	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
2023	$(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
2024
2025kernelrelease:
2026	@$(filechk_kernel.release)
2027
2028kernelversion:
2029	@echo $(KERNELVERSION)
2030
2031image_name:
2032	@echo $(KBUILD_IMAGE)
2033
2034PHONY += run-command
2035run-command:
2036	$(Q)$(KBUILD_RUN_COMMAND)
2037
2038quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
2039      cmd_rmfiles = rm -rf $(rm-files)
2040
2041# read saved command lines for existing targets
2042existing-targets := $(wildcard $(sort $(targets)))
2043
2044-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
2045
2046endif # config-build
2047endif # mixed-build
2048endif # need-sub-make
2049
2050PHONY += FORCE
2051FORCE:
2052
2053# Declare the contents of the PHONY variable as phony.  We keep that
2054# information in a variable so we can use it in if_changed and friends.
2055.PHONY: $(PHONY)
2056