xref: /openbmc/linux/Makefile (revision e8069f5a)
1# SPDX-License-Identifier: GPL-2.0
2VERSION = 6
3PATCHLEVEL = 4
4SUBLEVEL = 0
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 kernelrelease image_name
284no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease \
285			  image_name
286single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.rsi %.s %.symtypes %/
287
288config-build	:=
289mixed-build	:=
290need-config	:= 1
291need-compiler	:= 1
292may-sync-config	:= 1
293single-build	:=
294
295ifneq ($(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 \
453			 -Wdeclaration-after-statement
454KBUILD_USERCFLAGS  := $(KBUILD_USERHOSTCFLAGS) $(USERCFLAGS)
455KBUILD_USERLDFLAGS := $(USERLDFLAGS)
456
457# These flags apply to all Rust code in the tree, including the kernel and
458# host programs.
459export rust_common_flags := --edition=2021 \
460			    -Zbinary_dep_depinfo=y \
461			    -Dunsafe_op_in_unsafe_fn -Drust_2018_idioms \
462			    -Dunreachable_pub -Dnon_ascii_idents \
463			    -Wmissing_docs \
464			    -Drustdoc::missing_crate_level_docs \
465			    -Dclippy::correctness -Dclippy::style \
466			    -Dclippy::suspicious -Dclippy::complexity \
467			    -Dclippy::perf \
468			    -Dclippy::let_unit_value -Dclippy::mut_mut \
469			    -Dclippy::needless_bitwise_bool \
470			    -Dclippy::needless_continue \
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
513DEPMOD		= depmod
514PERL		= perl
515PYTHON3		= python3
516CHECK		= sparse
517BASH		= bash
518KGZIP		= gzip
519KBZIP2		= bzip2
520KLZOP		= lzop
521LZMA		= lzma
522LZ4		= lz4c
523XZ		= xz
524ZSTD		= zstd
525
526PAHOLE_FLAGS	= $(shell PAHOLE=$(PAHOLE) $(srctree)/scripts/pahole-flags.sh)
527
528CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
529		  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
530NOSTDINC_FLAGS :=
531CFLAGS_MODULE   =
532RUSTFLAGS_MODULE =
533AFLAGS_MODULE   =
534LDFLAGS_MODULE  =
535CFLAGS_KERNEL	=
536RUSTFLAGS_KERNEL =
537AFLAGS_KERNEL	=
538LDFLAGS_vmlinux =
539
540# Use USERINCLUDE when you must reference the UAPI directories only.
541USERINCLUDE    := \
542		-I$(srctree)/arch/$(SRCARCH)/include/uapi \
543		-I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
544		-I$(srctree)/include/uapi \
545		-I$(objtree)/include/generated/uapi \
546                -include $(srctree)/include/linux/compiler-version.h \
547                -include $(srctree)/include/linux/kconfig.h
548
549# Use LINUXINCLUDE when you must reference the include/ directory.
550# Needed to be compatible with the O= option
551LINUXINCLUDE    := \
552		-I$(srctree)/arch/$(SRCARCH)/include \
553		-I$(objtree)/arch/$(SRCARCH)/include/generated \
554		$(if $(building_out_of_srctree),-I$(srctree)/include) \
555		-I$(objtree)/include \
556		$(USERINCLUDE)
557
558KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
559KBUILD_CFLAGS   := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
560		   -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
561		   -Werror=implicit-function-declaration -Werror=implicit-int \
562		   -Werror=return-type -Wno-format-security -funsigned-char \
563		   -std=gnu11
564KBUILD_CPPFLAGS := -D__KERNEL__
565KBUILD_RUSTFLAGS := $(rust_common_flags) \
566		    --target=$(objtree)/scripts/target.json \
567		    -Cpanic=abort -Cembed-bitcode=n -Clto=n \
568		    -Cforce-unwind-tables=n -Ccodegen-units=1 \
569		    -Csymbol-mangling-version=v0 \
570		    -Crelocation-model=static \
571		    -Zfunction-sections=n \
572		    -Dclippy::float_arithmetic
573
574KBUILD_AFLAGS_KERNEL :=
575KBUILD_CFLAGS_KERNEL :=
576KBUILD_RUSTFLAGS_KERNEL :=
577KBUILD_AFLAGS_MODULE  := -DMODULE
578KBUILD_CFLAGS_MODULE  := -DMODULE
579KBUILD_RUSTFLAGS_MODULE := --cfg MODULE
580KBUILD_LDFLAGS_MODULE :=
581KBUILD_LDFLAGS :=
582CLANG_FLAGS :=
583
584ifeq ($(KBUILD_CLIPPY),1)
585	RUSTC_OR_CLIPPY_QUIET := CLIPPY
586	RUSTC_OR_CLIPPY = $(CLIPPY_DRIVER)
587else
588	RUSTC_OR_CLIPPY_QUIET := RUSTC
589	RUSTC_OR_CLIPPY = $(RUSTC)
590endif
591
592ifdef RUST_LIB_SRC
593	export RUST_LIB_SRC
594endif
595
596# Allows the usage of unstable features in stable compilers.
597export RUSTC_BOOTSTRAP := 1
598
599export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG
600export RUSTC RUSTDOC RUSTFMT RUSTC_OR_CLIPPY_QUIET RUSTC_OR_CLIPPY BINDGEN CARGO
601export HOSTRUSTC KBUILD_HOSTRUSTFLAGS
602export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
603export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
604export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
605export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
606export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS
607
608export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
609export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
610export KBUILD_RUSTFLAGS RUSTFLAGS_KERNEL RUSTFLAGS_MODULE
611export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
612export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_RUSTFLAGS_MODULE KBUILD_LDFLAGS_MODULE
613export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL KBUILD_RUSTFLAGS_KERNEL
614export PAHOLE_FLAGS
615
616# Files to ignore in find ... statements
617
618export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
619			  -name CVS -o -name .pc -o -name .hg -o -name .git \) \
620			  -prune -o
621export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
622			 --exclude CVS --exclude .pc --exclude .hg --exclude .git
623
624# ===========================================================================
625# Rules shared between *config targets and build targets
626
627# Basic helpers built in scripts/basic/
628PHONY += scripts_basic
629scripts_basic:
630	$(Q)$(MAKE) $(build)=scripts/basic
631
632PHONY += outputmakefile
633ifdef building_out_of_srctree
634# Before starting out-of-tree build, make sure the source tree is clean.
635# outputmakefile generates a Makefile in the output directory, if using a
636# separate output directory. This allows convenient use of make in the
637# output directory.
638# At the same time when output Makefile generated, generate .gitignore to
639# ignore whole output directory
640
641quiet_cmd_makefile = GEN     Makefile
642      cmd_makefile = { \
643	echo "\# Automatically generated by $(srctree)/Makefile: don't edit"; \
644	echo "include $(srctree)/Makefile"; \
645	} > Makefile
646
647outputmakefile:
648	@if [ -f $(srctree)/.config -o \
649		 -d $(srctree)/include/config -o \
650		 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
651		echo >&2 "***"; \
652		echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
653		echo >&2 "*** in $(abs_srctree)";\
654		echo >&2 "***"; \
655		false; \
656	fi
657	$(Q)ln -fsn $(srctree) source
658	$(call cmd,makefile)
659	$(Q)test -e .gitignore || \
660	{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
661endif
662
663# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
664# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
665# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
666# and from include/config/auto.conf.cmd to detect the compiler upgrade.
667CC_VERSION_TEXT = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1))
668
669ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
670include $(srctree)/scripts/Makefile.clang
671endif
672
673# Include this also for config targets because some architectures need
674# cc-cross-prefix to determine CROSS_COMPILE.
675ifdef need-compiler
676include $(srctree)/scripts/Makefile.compiler
677endif
678
679ifdef config-build
680# ===========================================================================
681# *config targets only - make sure prerequisites are updated, and descend
682# in scripts/kconfig to make the *config target
683
684# Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
685# KBUILD_DEFCONFIG may point out an alternative default configuration
686# used for 'make defconfig'
687include $(srctree)/arch/$(SRCARCH)/Makefile
688export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
689
690config: outputmakefile scripts_basic FORCE
691	$(Q)$(MAKE) $(build)=scripts/kconfig $@
692
693%config: outputmakefile scripts_basic FORCE
694	$(Q)$(MAKE) $(build)=scripts/kconfig $@
695
696else #!config-build
697# ===========================================================================
698# Build targets only - this includes vmlinux, arch specific targets, clean
699# targets and others. In general all targets except *config targets.
700
701# If building an external module we do not care about the all: rule
702# but instead __all depend on modules
703PHONY += all
704ifeq ($(KBUILD_EXTMOD),)
705__all: all
706else
707__all: modules
708endif
709
710targets :=
711
712# Decide whether to build built-in, modular, or both.
713# Normally, just do built-in.
714
715KBUILD_MODULES :=
716KBUILD_BUILTIN := 1
717
718# If we have only "make modules", don't compile built-in objects.
719ifeq ($(MAKECMDGOALS),modules)
720  KBUILD_BUILTIN :=
721endif
722
723# If we have "make <whatever> modules", compile modules
724# in addition to whatever we do anyway.
725# Just "make" or "make all" shall build modules as well
726
727ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
728  KBUILD_MODULES := 1
729endif
730
731ifeq ($(MAKECMDGOALS),)
732  KBUILD_MODULES := 1
733endif
734
735export KBUILD_MODULES KBUILD_BUILTIN
736
737ifdef need-config
738include include/config/auto.conf
739endif
740
741ifeq ($(KBUILD_EXTMOD),)
742# Objects we will link into vmlinux / subdirs we need to visit
743core-y		:=
744drivers-y	:=
745libs-y		:= lib/
746endif # KBUILD_EXTMOD
747
748# The all: target is the default when no target is given on the
749# command line.
750# This allow a user to issue only 'make' to build a kernel including modules
751# Defaults to vmlinux, but the arch makefile usually adds further targets
752all: vmlinux
753
754CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage
755ifdef CONFIG_CC_IS_GCC
756CFLAGS_GCOV	+= -fno-tree-loop-im
757endif
758export CFLAGS_GCOV
759
760# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
761ifdef CONFIG_FUNCTION_TRACER
762  CC_FLAGS_FTRACE := -pg
763endif
764
765include $(srctree)/arch/$(SRCARCH)/Makefile
766
767ifdef need-config
768ifdef may-sync-config
769# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
770# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
771# because some architectures define CROSS_COMPILE there.
772include include/config/auto.conf.cmd
773
774$(KCONFIG_CONFIG):
775	@echo >&2 '***'
776	@echo >&2 '*** Configuration file "$@" not found!'
777	@echo >&2 '***'
778	@echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
779	@echo >&2 '*** "make menuconfig" or "make xconfig").'
780	@echo >&2 '***'
781	@/bin/false
782
783# The actual configuration files used during the build are stored in
784# include/generated/ and include/config/. Update them if .config is newer than
785# include/config/auto.conf (which mirrors .config).
786#
787# This exploits the 'multi-target pattern rule' trick.
788# The syncconfig should be executed only once to make all the targets.
789# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
790#
791# Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
792# so you cannot notice that Kconfig is waiting for the user input.
793%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h %/generated/rustc_cfg: $(KCONFIG_CONFIG)
794	$(Q)$(kecho) "  SYNC    $@"
795	$(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
796else # !may-sync-config
797# External modules and some install targets need include/generated/autoconf.h
798# and include/config/auto.conf but do not care if they are up-to-date.
799# Use auto.conf to trigger the test
800PHONY += include/config/auto.conf
801
802include/config/auto.conf:
803	@test -e include/generated/autoconf.h -a -e $@ || (		\
804	echo >&2;							\
805	echo >&2 "  ERROR: Kernel configuration is invalid.";		\
806	echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
807	echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";	\
808	echo >&2 ;							\
809	/bin/false)
810
811endif # may-sync-config
812endif # need-config
813
814KBUILD_CFLAGS	+= -fno-delete-null-pointer-checks
815KBUILD_CFLAGS	+= $(call cc-disable-warning,frame-address,)
816KBUILD_CFLAGS	+= $(call cc-disable-warning, format-truncation)
817KBUILD_CFLAGS	+= $(call cc-disable-warning, format-overflow)
818KBUILD_CFLAGS	+= $(call cc-disable-warning, address-of-packed-member)
819
820ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
821KBUILD_CFLAGS += -O2
822KBUILD_RUSTFLAGS += -Copt-level=2
823else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
824KBUILD_CFLAGS += -Os
825KBUILD_RUSTFLAGS += -Copt-level=s
826endif
827
828# Always set `debug-assertions` and `overflow-checks` because their default
829# depends on `opt-level` and `debug-assertions`, respectively.
830KBUILD_RUSTFLAGS += -Cdebug-assertions=$(if $(CONFIG_RUST_DEBUG_ASSERTIONS),y,n)
831KBUILD_RUSTFLAGS += -Coverflow-checks=$(if $(CONFIG_RUST_OVERFLOW_CHECKS),y,n)
832
833# Tell gcc to never replace conditional load with a non-conditional one
834ifdef CONFIG_CC_IS_GCC
835# gcc-10 renamed --param=allow-store-data-races=0 to
836# -fno-allow-store-data-races.
837KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
838KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
839endif
840
841ifdef CONFIG_READABLE_ASM
842# Disable optimizations that make assembler listings hard to read.
843# reorder blocks reorders the control in the function
844# ipa clone creates specialized cloned functions
845# partial inlining inlines only parts of functions
846KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
847endif
848
849ifneq ($(CONFIG_FRAME_WARN),0)
850KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
851endif
852
853stackp-flags-y                                    := -fno-stack-protector
854stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
855stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
856
857KBUILD_CFLAGS += $(stackp-flags-y)
858
859KBUILD_CPPFLAGS-$(CONFIG_WERROR) += -Werror
860KBUILD_CPPFLAGS += $(KBUILD_CPPFLAGS-y)
861KBUILD_CFLAGS-$(CONFIG_CC_NO_ARRAY_BOUNDS) += -Wno-array-bounds
862
863KBUILD_RUSTFLAGS-$(CONFIG_WERROR) += -Dwarnings
864KBUILD_RUSTFLAGS += $(KBUILD_RUSTFLAGS-y)
865
866ifdef CONFIG_CC_IS_CLANG
867# The kernel builds with '-std=gnu11' so use of GNU extensions is acceptable.
868KBUILD_CFLAGS += -Wno-gnu
869else
870
871# gcc inanely warns about local variables called 'main'
872KBUILD_CFLAGS += -Wno-main
873endif
874
875# These warnings generated too much noise in a regular build.
876# Use make W=1 to enable them (see scripts/Makefile.extrawarn)
877KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
878KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
879
880# These result in bogus false positives
881KBUILD_CFLAGS += $(call cc-disable-warning, dangling-pointer)
882
883ifdef CONFIG_FRAME_POINTER
884KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
885KBUILD_RUSTFLAGS += -Cforce-frame-pointers=y
886else
887# Some targets (ARM with Thumb2, for example), can't be built with frame
888# pointers.  For those, we don't have FUNCTION_TRACER automatically
889# select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
890# incompatible with -fomit-frame-pointer with current GCC, so we don't use
891# -fomit-frame-pointer with FUNCTION_TRACER.
892# In the Rust target specification, "frame-pointer" is set explicitly
893# to "may-omit".
894ifndef CONFIG_FUNCTION_TRACER
895KBUILD_CFLAGS	+= -fomit-frame-pointer
896endif
897endif
898
899# Initialize all stack variables with a 0xAA pattern.
900ifdef CONFIG_INIT_STACK_ALL_PATTERN
901KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
902endif
903
904# Initialize all stack variables with a zero value.
905ifdef CONFIG_INIT_STACK_ALL_ZERO
906KBUILD_CFLAGS	+= -ftrivial-auto-var-init=zero
907ifdef CONFIG_CC_HAS_AUTO_VAR_INIT_ZERO_ENABLER
908# https://github.com/llvm/llvm-project/issues/44842
909CC_AUTO_VAR_INIT_ZERO_ENABLER := -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
910export CC_AUTO_VAR_INIT_ZERO_ENABLER
911KBUILD_CFLAGS	+= $(CC_AUTO_VAR_INIT_ZERO_ENABLER)
912endif
913endif
914
915# While VLAs have been removed, GCC produces unreachable stack probes
916# for the randomize_kstack_offset feature. Disable it for all compilers.
917KBUILD_CFLAGS	+= $(call cc-option, -fno-stack-clash-protection)
918
919# Clear used registers at func exit (to reduce data lifetime and ROP gadgets).
920ifdef CONFIG_ZERO_CALL_USED_REGS
921KBUILD_CFLAGS	+= -fzero-call-used-regs=used-gpr
922endif
923
924ifdef CONFIG_FUNCTION_TRACER
925ifdef CONFIG_FTRACE_MCOUNT_USE_CC
926  CC_FLAGS_FTRACE	+= -mrecord-mcount
927  ifdef CONFIG_HAVE_NOP_MCOUNT
928    ifeq ($(call cc-option-yn, -mnop-mcount),y)
929      CC_FLAGS_FTRACE	+= -mnop-mcount
930      CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
931    endif
932  endif
933endif
934ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
935  ifdef CONFIG_HAVE_OBJTOOL_NOP_MCOUNT
936    CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
937  endif
938endif
939ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
940  ifdef CONFIG_HAVE_C_RECORDMCOUNT
941    BUILD_C_RECORDMCOUNT := y
942    export BUILD_C_RECORDMCOUNT
943  endif
944endif
945ifdef CONFIG_HAVE_FENTRY
946  # s390-linux-gnu-gcc did not support -mfentry until gcc-9.
947  ifeq ($(call cc-option-yn, -mfentry),y)
948    CC_FLAGS_FTRACE	+= -mfentry
949    CC_FLAGS_USING	+= -DCC_USING_FENTRY
950  endif
951endif
952export CC_FLAGS_FTRACE
953KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
954KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
955endif
956
957# We trigger additional mismatches with less inlining
958ifdef CONFIG_DEBUG_SECTION_MISMATCH
959KBUILD_CFLAGS += -fno-inline-functions-called-once
960endif
961
962# `rustc`'s `-Zfunction-sections` applies to data too (as of 1.59.0).
963ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
964KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
965KBUILD_RUSTFLAGS_KERNEL += -Zfunction-sections=y
966LDFLAGS_vmlinux += --gc-sections
967endif
968
969ifdef CONFIG_SHADOW_CALL_STACK
970ifndef CONFIG_DYNAMIC_SCS
971CC_FLAGS_SCS	:= -fsanitize=shadow-call-stack
972KBUILD_CFLAGS	+= $(CC_FLAGS_SCS)
973endif
974export CC_FLAGS_SCS
975endif
976
977ifdef CONFIG_LTO_CLANG
978ifdef CONFIG_LTO_CLANG_THIN
979CC_FLAGS_LTO	:= -flto=thin -fsplit-lto-unit
980KBUILD_LDFLAGS	+= --thinlto-cache-dir=$(extmod_prefix).thinlto-cache
981else
982CC_FLAGS_LTO	:= -flto
983endif
984CC_FLAGS_LTO	+= -fvisibility=hidden
985
986# Limit inlining across translation units to reduce binary size
987KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
988
989# Check for frame size exceeding threshold during prolog/epilog insertion
990# when using lld < 13.0.0.
991ifneq ($(CONFIG_FRAME_WARN),0)
992ifeq ($(call test-lt, $(CONFIG_LLD_VERSION), 130000),y)
993KBUILD_LDFLAGS	+= -plugin-opt=-warn-stack-size=$(CONFIG_FRAME_WARN)
994endif
995endif
996endif
997
998ifdef CONFIG_LTO
999KBUILD_CFLAGS	+= -fno-lto $(CC_FLAGS_LTO)
1000KBUILD_AFLAGS	+= -fno-lto
1001export CC_FLAGS_LTO
1002endif
1003
1004ifdef CONFIG_CFI_CLANG
1005CC_FLAGS_CFI	:= -fsanitize=kcfi
1006KBUILD_CFLAGS	+= $(CC_FLAGS_CFI)
1007export CC_FLAGS_CFI
1008endif
1009
1010ifneq ($(CONFIG_FUNCTION_ALIGNMENT),0)
1011KBUILD_CFLAGS += -falign-functions=$(CONFIG_FUNCTION_ALIGNMENT)
1012endif
1013
1014# arch Makefile may override CC so keep this after arch Makefile is included
1015NOSTDINC_FLAGS += -nostdinc
1016
1017# warn about C99 declaration after statement
1018KBUILD_CFLAGS += -Wdeclaration-after-statement
1019
1020# Variable Length Arrays (VLAs) should not be used anywhere in the kernel
1021KBUILD_CFLAGS += -Wvla
1022
1023# disable pointer signed / unsigned warnings in gcc 4.0
1024KBUILD_CFLAGS += -Wno-pointer-sign
1025
1026# In order to make sure new function cast mismatches are not introduced
1027# in the kernel (to avoid tripping CFI checking), the kernel should be
1028# globally built with -Wcast-function-type.
1029KBUILD_CFLAGS += $(call cc-option, -Wcast-function-type)
1030
1031# To gain proper coverage for CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE,
1032# the kernel uses only C99 flexible arrays for dynamically sized trailing
1033# arrays. Enforce this for everything that may examine structure sizes and
1034# perform bounds checking.
1035KBUILD_CFLAGS += $(call cc-option, -fstrict-flex-arrays=3)
1036
1037# disable stringop warnings in gcc 8+
1038KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
1039
1040# We'll want to enable this eventually, but it's not going away for 5.7 at least
1041KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
1042
1043# Another good warning that we'll want to enable eventually
1044KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
1045
1046# Enabled with W=2, disabled by default as noisy
1047ifdef CONFIG_CC_IS_GCC
1048KBUILD_CFLAGS += -Wno-maybe-uninitialized
1049endif
1050
1051# The allocators already balk at large sizes, so silence the compiler
1052# warnings for bounds checks involving those possible values. While
1053# -Wno-alloc-size-larger-than would normally be used here, earlier versions
1054# of gcc (<9.1) weirdly don't handle the option correctly when _other_
1055# warnings are produced (?!). Using -Walloc-size-larger-than=SIZE_MAX
1056# doesn't work (as it is documented to), silently resolving to "0" prior to
1057# version 9.1 (and producing an error more recently). Numeric values larger
1058# than PTRDIFF_MAX also don't work prior to version 9.1, which are silently
1059# ignored, continuing to default to PTRDIFF_MAX. So, left with no other
1060# choice, we must perform a versioned check to disable this warning.
1061# https://lore.kernel.org/lkml/20210824115859.187f272f@canb.auug.org.au
1062KBUILD_CFLAGS-$(call gcc-min-version, 90100) += -Wno-alloc-size-larger-than
1063KBUILD_CFLAGS += $(KBUILD_CFLAGS-y) $(CONFIG_CC_IMPLICIT_FALLTHROUGH)
1064
1065# disable invalid "can't wrap" optimizations for signed / pointers
1066KBUILD_CFLAGS	+= -fno-strict-overflow
1067
1068# Make sure -fstack-check isn't enabled (like gentoo apparently did)
1069KBUILD_CFLAGS  += -fno-stack-check
1070
1071# conserve stack if available
1072ifdef CONFIG_CC_IS_GCC
1073KBUILD_CFLAGS   += -fconserve-stack
1074endif
1075
1076# Prohibit date/time macros, which would make the build non-deterministic
1077KBUILD_CFLAGS   += -Werror=date-time
1078
1079# enforce correct pointer usage
1080KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)
1081
1082# Require designated initializers for all marked structures
1083KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)
1084
1085# change __FILE__ to the relative path from the srctree
1086KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
1087
1088# include additional Makefiles when needed
1089include-y			:= scripts/Makefile.extrawarn
1090include-$(CONFIG_DEBUG_INFO)	+= scripts/Makefile.debug
1091include-$(CONFIG_KASAN)		+= scripts/Makefile.kasan
1092include-$(CONFIG_KCSAN)		+= scripts/Makefile.kcsan
1093include-$(CONFIG_KMSAN)		+= scripts/Makefile.kmsan
1094include-$(CONFIG_UBSAN)		+= scripts/Makefile.ubsan
1095include-$(CONFIG_KCOV)		+= scripts/Makefile.kcov
1096include-$(CONFIG_RANDSTRUCT)	+= scripts/Makefile.randstruct
1097include-$(CONFIG_GCC_PLUGINS)	+= scripts/Makefile.gcc-plugins
1098
1099include $(addprefix $(srctree)/, $(include-y))
1100
1101# scripts/Makefile.gcc-plugins is intentionally included last.
1102# Do not add $(call cc-option,...) below this line. When you build the kernel
1103# from the clean source tree, the GCC plugins do not exist at this point.
1104
1105# Add user supplied CPPFLAGS, AFLAGS, CFLAGS and RUSTFLAGS as the last assignments
1106KBUILD_CPPFLAGS += $(KCPPFLAGS)
1107KBUILD_AFLAGS   += $(KAFLAGS)
1108KBUILD_CFLAGS   += $(KCFLAGS)
1109KBUILD_RUSTFLAGS += $(KRUSTFLAGS)
1110
1111KBUILD_LDFLAGS_MODULE += --build-id=sha1
1112LDFLAGS_vmlinux += --build-id=sha1
1113
1114KBUILD_LDFLAGS	+= -z noexecstack
1115ifeq ($(CONFIG_LD_IS_BFD),y)
1116KBUILD_LDFLAGS	+= $(call ld-option,--no-warn-rwx-segments)
1117endif
1118
1119ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1120LDFLAGS_vmlinux	+= -X
1121endif
1122
1123ifeq ($(CONFIG_RELR),y)
1124# ld.lld before 15 did not support -z pack-relative-relocs.
1125LDFLAGS_vmlinux	+= $(call ld-option,--pack-dyn-relocs=relr,-z pack-relative-relocs)
1126endif
1127
1128# We never want expected sections to be placed heuristically by the
1129# linker. All sections should be explicitly named in the linker script.
1130ifdef CONFIG_LD_ORPHAN_WARN
1131LDFLAGS_vmlinux += --orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL)
1132endif
1133
1134# Align the bit size of userspace programs with the kernel
1135KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1136KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1137
1138# make the checker run with the right architecture
1139CHECKFLAGS += --arch=$(ARCH)
1140
1141# insure the checker run with the right endianness
1142CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1143
1144# the checker needs the correct machine size
1145CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1146
1147# Default kernel image to build when no specific target is given.
1148# KBUILD_IMAGE may be overruled on the command line or
1149# set in the environment
1150# Also any assignments in arch/$(ARCH)/Makefile take precedence over
1151# this default value
1152export KBUILD_IMAGE ?= vmlinux
1153
1154#
1155# INSTALL_PATH specifies where to place the updated kernel and system map
1156# images. Default is /boot, but you can set it to other values
1157export	INSTALL_PATH ?= /boot
1158
1159#
1160# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1161# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1162# an argument if needed. Otherwise it defaults to the kernel install path
1163#
1164export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1165
1166#
1167# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1168# relocations required by build roots.  This is not defined in the
1169# makefile but the argument can be passed to make if needed.
1170#
1171
1172MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1173export MODLIB
1174
1175PHONY += prepare0
1176
1177export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
1178export MODORDER := $(extmod_prefix)modules.order
1179export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
1180
1181ifeq ($(KBUILD_EXTMOD),)
1182
1183build-dir	:= .
1184clean-dirs	:= $(sort . Documentation \
1185		     $(patsubst %/,%,$(filter %/, $(core-) \
1186			$(drivers-) $(libs-))))
1187
1188export ARCH_CORE	:= $(core-y)
1189export ARCH_LIB		:= $(filter %/, $(libs-y))
1190export ARCH_DRIVERS	:= $(drivers-y) $(drivers-m)
1191# Externally visible symbols (used by link-vmlinux.sh)
1192
1193KBUILD_VMLINUX_OBJS := ./built-in.a
1194ifdef CONFIG_MODULES
1195KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1196KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1197else
1198KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1199endif
1200
1201export KBUILD_VMLINUX_LIBS
1202export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1203
1204ifdef CONFIG_TRIM_UNUSED_KSYMS
1205# For the kernel to actually contain only the needed exported symbols,
1206# we have to build modules as well to determine what those symbols are.
1207KBUILD_MODULES := 1
1208endif
1209
1210# '$(AR) mPi' needs 'T' to workaround the bug of llvm-ar <= 14
1211quiet_cmd_ar_vmlinux.a = AR      $@
1212      cmd_ar_vmlinux.a = \
1213	rm -f $@; \
1214	$(AR) cDPrST $@ $(KBUILD_VMLINUX_OBJS); \
1215	$(AR) mPiT $$($(AR) t $@ | sed -n 1p) $@ $$($(AR) t $@ | grep -F -f $(srctree)/scripts/head-object-list.txt)
1216
1217targets += vmlinux.a
1218vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt FORCE
1219	$(call if_changed,ar_vmlinux.a)
1220
1221PHONY += vmlinux_o
1222vmlinux_o: vmlinux.a $(KBUILD_VMLINUX_LIBS)
1223	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o
1224
1225vmlinux.o modules.builtin.modinfo modules.builtin: vmlinux_o
1226	@:
1227
1228PHONY += vmlinux
1229# LDFLAGS_vmlinux in the top Makefile defines linker flags for the top vmlinux,
1230# not for decompressors. LDFLAGS_vmlinux in arch/*/boot/compressed/Makefile is
1231# unrelated; the decompressors just happen to have the same base name,
1232# arch/*/boot/compressed/vmlinux.
1233# Export LDFLAGS_vmlinux only to scripts/Makefile.vmlinux.
1234#
1235# _LDFLAGS_vmlinux is a workaround for the 'private export' bug:
1236#   https://savannah.gnu.org/bugs/?61463
1237# For Make > 4.4, the following simple code will work:
1238#  vmlinux: private export LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1239vmlinux: private _LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1240vmlinux: export LDFLAGS_vmlinux = $(_LDFLAGS_vmlinux)
1241vmlinux: vmlinux.o $(KBUILD_LDS) modpost
1242	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux
1243
1244# The actual objects are generated when descending,
1245# make sure no implicit rule kicks in
1246$(sort $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)): . ;
1247
1248ifeq ($(origin KERNELRELEASE),file)
1249filechk_kernel.release = $(srctree)/scripts/setlocalversion $(srctree)
1250else
1251filechk_kernel.release = echo $(KERNELRELEASE)
1252endif
1253
1254# Store (new) KERNELRELEASE string in include/config/kernel.release
1255include/config/kernel.release: FORCE
1256	$(call filechk,kernel.release)
1257
1258# Additional helpers built in scripts/
1259# Carefully list dependencies so we do not try to build scripts twice
1260# in parallel
1261PHONY += scripts
1262scripts: scripts_basic scripts_dtc
1263	$(Q)$(MAKE) $(build)=$(@)
1264
1265# Things we need to do before we recursively start building the kernel
1266# or the modules are listed in "prepare".
1267# A multi level approach is used. prepareN is processed before prepareN-1.
1268# archprepare is used in arch Makefiles and when processed asm symlink,
1269# version.h and scripts_basic is processed / created.
1270
1271PHONY += prepare archprepare
1272
1273archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1274	asm-generic $(version_h) include/generated/utsrelease.h \
1275	include/generated/compile.h include/generated/autoconf.h remove-stale-files
1276
1277prepare0: archprepare
1278	$(Q)$(MAKE) $(build)=scripts/mod
1279	$(Q)$(MAKE) $(build)=. prepare
1280
1281# All the preparing..
1282prepare: prepare0
1283ifdef CONFIG_RUST
1284	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh -v
1285	$(Q)$(MAKE) $(build)=rust
1286endif
1287
1288PHONY += remove-stale-files
1289remove-stale-files:
1290	$(Q)$(srctree)/scripts/remove-stale-files
1291
1292# Support for using generic headers in asm-generic
1293asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1294
1295PHONY += asm-generic uapi-asm-generic
1296asm-generic: uapi-asm-generic
1297	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1298	generic=include/asm-generic
1299uapi-asm-generic:
1300	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1301	generic=include/uapi/asm-generic
1302
1303# Generate some files
1304# ---------------------------------------------------------------------------
1305
1306# KERNELRELEASE can change from a few different places, meaning version.h
1307# needs to be updated, so this check is forced on all builds
1308
1309uts_len := 64
1310define filechk_utsrelease.h
1311	if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1312	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1313	  exit 1;                                                         \
1314	fi;                                                               \
1315	echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1316endef
1317
1318define filechk_version.h
1319	if [ $(SUBLEVEL) -gt 255 ]; then                                 \
1320		echo \#define LINUX_VERSION_CODE $(shell                 \
1321		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1322	else                                                             \
1323		echo \#define LINUX_VERSION_CODE $(shell                 \
1324		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1325	fi;                                                              \
1326	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
1327	((c) > 255 ? 255 : (c)))';                                       \
1328	echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
1329	echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
1330	echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1331endef
1332
1333$(version_h): PATCHLEVEL := $(or $(PATCHLEVEL), 0)
1334$(version_h): SUBLEVEL := $(or $(SUBLEVEL), 0)
1335$(version_h): FORCE
1336	$(call filechk,version.h)
1337
1338include/generated/utsrelease.h: include/config/kernel.release FORCE
1339	$(call filechk,utsrelease.h)
1340
1341filechk_compile.h = $(srctree)/scripts/mkcompile_h \
1342	"$(UTS_MACHINE)" "$(CONFIG_CC_VERSION_TEXT)" "$(LD)"
1343
1344include/generated/compile.h: FORCE
1345	$(call filechk,compile.h)
1346
1347PHONY += headerdep
1348headerdep:
1349	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1350	$(srctree)/scripts/headerdep.pl -I$(srctree)/include
1351
1352# ---------------------------------------------------------------------------
1353# Kernel headers
1354
1355#Default location for installed headers
1356export INSTALL_HDR_PATH = $(objtree)/usr
1357
1358quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1359      cmd_headers_install = \
1360	mkdir -p $(INSTALL_HDR_PATH); \
1361	rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1362	usr/include $(INSTALL_HDR_PATH)
1363
1364PHONY += headers_install
1365headers_install: headers
1366	$(call cmd,headers_install)
1367
1368PHONY += archheaders archscripts
1369
1370hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1371
1372PHONY += headers
1373headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1374	$(if $(filter um, $(SRCARCH)), $(error Headers not exportable for UML))
1375	$(Q)$(MAKE) $(hdr-inst)=include/uapi
1376	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1377
1378ifdef CONFIG_HEADERS_INSTALL
1379prepare: headers
1380endif
1381
1382PHONY += scripts_unifdef
1383scripts_unifdef: scripts_basic
1384	$(Q)$(MAKE) $(build)=scripts scripts/unifdef
1385
1386# ---------------------------------------------------------------------------
1387# Install
1388
1389# Many distributions have the custom install script, /sbin/installkernel.
1390# If DKMS is installed, 'make install' will eventually recurse back
1391# to this Makefile to build and install external modules.
1392# Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
1393
1394quiet_cmd_install = INSTALL $(INSTALL_PATH)
1395      cmd_install = unset sub_make_done; $(srctree)/scripts/install.sh
1396
1397# ---------------------------------------------------------------------------
1398# Tools
1399
1400ifdef CONFIG_OBJTOOL
1401prepare: tools/objtool
1402endif
1403
1404ifdef CONFIG_BPF
1405ifdef CONFIG_DEBUG_INFO_BTF
1406prepare: tools/bpf/resolve_btfids
1407endif
1408endif
1409
1410PHONY += resolve_btfids_clean
1411
1412resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1413
1414# tools/bpf/resolve_btfids directory might not exist
1415# in output directory, skip its clean in that case
1416resolve_btfids_clean:
1417ifneq ($(wildcard $(resolve_btfids_O)),)
1418	$(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1419endif
1420
1421# Clear a bunch of variables before executing the submake
1422ifeq ($(quiet),silent_)
1423tools_silent=s
1424endif
1425
1426tools/: FORCE
1427	$(Q)mkdir -p $(objtree)/tools
1428	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1429
1430tools/%: FORCE
1431	$(Q)mkdir -p $(objtree)/tools
1432	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1433
1434# ---------------------------------------------------------------------------
1435# Kernel selftest
1436
1437PHONY += kselftest
1438kselftest: headers
1439	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1440
1441kselftest-%: headers FORCE
1442	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1443
1444PHONY += kselftest-merge
1445kselftest-merge:
1446	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1447	$(Q)find $(srctree)/tools/testing/selftests -name config | \
1448		xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1449	$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1450
1451# ---------------------------------------------------------------------------
1452# Devicetree files
1453
1454ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1455dtstree := arch/$(SRCARCH)/boot/dts
1456endif
1457
1458ifneq ($(dtstree),)
1459
1460%.dtb: dtbs_prepare
1461	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1462
1463%.dtbo: dtbs_prepare
1464	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1465
1466PHONY += dtbs dtbs_prepare dtbs_install dtbs_check
1467dtbs: dtbs_prepare
1468	$(Q)$(MAKE) $(build)=$(dtstree)
1469
1470# include/config/kernel.release is actually needed when installing DTBs because
1471# INSTALL_DTBS_PATH contains $(KERNELRELEASE). However, we do not want to make
1472# dtbs_install depend on it as dtbs_install may run as root.
1473dtbs_prepare: include/config/kernel.release scripts_dtc
1474
1475ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1476export CHECK_DTBS=y
1477endif
1478
1479ifneq ($(CHECK_DTBS),)
1480dtbs_prepare: dt_binding_check
1481endif
1482
1483dtbs_check: dtbs
1484
1485dtbs_install:
1486	$(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1487
1488ifdef CONFIG_OF_EARLY_FLATTREE
1489all: dtbs
1490endif
1491
1492endif
1493
1494PHONY += scripts_dtc
1495scripts_dtc: scripts_basic
1496	$(Q)$(MAKE) $(build)=scripts/dtc
1497
1498ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1499export CHECK_DT_BINDING=y
1500endif
1501
1502PHONY += dt_binding_check
1503dt_binding_check: scripts_dtc
1504	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1505
1506PHONY += dt_compatible_check
1507dt_compatible_check: dt_binding_check
1508	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1509
1510# ---------------------------------------------------------------------------
1511# Modules
1512
1513ifdef CONFIG_MODULES
1514
1515# By default, build modules as well
1516
1517all: modules
1518
1519# When we're building modules with modversions, we need to consider
1520# the built-in objects during the descend as well, in order to
1521# make sure the checksums are up to date before we record them.
1522ifdef CONFIG_MODVERSIONS
1523  KBUILD_BUILTIN := 1
1524endif
1525
1526# Build modules
1527#
1528
1529# *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFO_BTF_MODULES
1530# is an exception.
1531ifdef CONFIG_DEBUG_INFO_BTF_MODULES
1532KBUILD_BUILTIN := 1
1533modules: vmlinux
1534endif
1535
1536modules: modules_prepare
1537
1538# Target to prepare building external modules
1539modules_prepare: prepare
1540	$(Q)$(MAKE) $(build)=scripts scripts/module.lds
1541
1542export modules_sign_only :=
1543
1544ifeq ($(CONFIG_MODULE_SIG),y)
1545PHONY += modules_sign
1546modules_sign: modules_install
1547	@:
1548
1549# modules_sign is a subset of modules_install.
1550# 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1551ifeq ($(filter modules_install,$(MAKECMDGOALS)),)
1552modules_sign_only := y
1553endif
1554endif
1555
1556endif # CONFIG_MODULES
1557
1558modinst_pre :=
1559ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
1560modinst_pre := __modinst_pre
1561endif
1562
1563modules_install: $(modinst_pre)
1564PHONY += __modinst_pre
1565__modinst_pre:
1566	@rm -rf $(MODLIB)/kernel
1567	@rm -f $(MODLIB)/source
1568	@mkdir -p $(MODLIB)
1569ifdef CONFIG_MODULES
1570	@ln -s $(abspath $(srctree)) $(MODLIB)/source
1571	@if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
1572		rm -f $(MODLIB)/build ; \
1573		ln -s $(CURDIR) $(MODLIB)/build ; \
1574	fi
1575	@sed 's:^\(.*\)\.o$$:kernel/\1.ko:' modules.order > $(MODLIB)/modules.order
1576endif
1577	@cp -f modules.builtin $(MODLIB)/
1578	@cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
1579
1580###
1581# Cleaning is done on three levels.
1582# make clean     Delete most generated files
1583#                Leave enough to build external modules
1584# make mrproper  Delete the current configuration, and all generated files
1585# make distclean Remove editor backup files, patch leftover files and the like
1586
1587# Directories & files removed with 'make clean'
1588CLEAN_FILES += include/ksym vmlinux.symvers modules-only.symvers \
1589	       modules.builtin modules.builtin.modinfo modules.nsdeps \
1590	       compile_commands.json .thinlto-cache rust/test rust/doc \
1591	       rust-project.json .vmlinux.objs .vmlinux.export.c
1592
1593# Directories & files removed with 'make mrproper'
1594MRPROPER_FILES += include/config include/generated          \
1595		  arch/$(SRCARCH)/include/generated .objdiff \
1596		  debian snap tar-install \
1597		  .config .config.old .version \
1598		  Module.symvers \
1599		  certs/signing_key.pem \
1600		  certs/x509.genkey \
1601		  vmlinux-gdb.py \
1602		  *.spec rpmbuild \
1603		  rust/libmacros.so
1604
1605# clean - Delete most, but leave enough to build external modules
1606#
1607clean: rm-files := $(CLEAN_FILES)
1608
1609PHONY += archclean vmlinuxclean
1610
1611vmlinuxclean:
1612	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1613	$(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1614
1615clean: archclean vmlinuxclean resolve_btfids_clean
1616
1617# mrproper - Delete all generated files, including .config
1618#
1619mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1620mrproper-dirs      := $(addprefix _mrproper_,scripts)
1621
1622PHONY += $(mrproper-dirs) mrproper
1623$(mrproper-dirs):
1624	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1625
1626mrproper: clean $(mrproper-dirs)
1627	$(call cmd,rmfiles)
1628	@find . $(RCS_FIND_IGNORE) \
1629		\( -name '*.rmeta' \) \
1630		-type f -print | xargs rm -f
1631
1632# distclean
1633#
1634PHONY += distclean
1635
1636distclean: mrproper
1637	@find . $(RCS_FIND_IGNORE) \
1638		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1639		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
1640		-o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1641		-o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1642		-type f -print | xargs rm -f
1643
1644
1645# Packaging of the kernel to various formats
1646# ---------------------------------------------------------------------------
1647
1648%src-pkg: FORCE
1649	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1650%pkg: include/config/kernel.release FORCE
1651	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1652
1653# Brief documentation of the typical targets used
1654# ---------------------------------------------------------------------------
1655
1656boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1657boards := $(sort $(notdir $(boards)))
1658board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1659board-dirs := $(sort $(notdir $(board-dirs:/=)))
1660
1661PHONY += help
1662help:
1663	@echo  'Cleaning targets:'
1664	@echo  '  clean		  - Remove most generated files but keep the config and'
1665	@echo  '                    enough build support to build external modules'
1666	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
1667	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
1668	@echo  ''
1669	@echo  'Configuration targets:'
1670	@$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1671	@echo  ''
1672	@echo  'Other generic targets:'
1673	@echo  '  all		  - Build all targets marked with [*]'
1674	@echo  '* vmlinux	  - Build the bare kernel'
1675	@echo  '* modules	  - Build all modules'
1676	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1677	@echo  '  dir/            - Build all files in dir and below'
1678	@echo  '  dir/file.[ois]  - Build specified target only'
1679	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1680	@echo  '                    (requires compiler support for LLVM assembly generation)'
1681	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1682	@echo  '                    (requires a recent binutils and recent build (System.map))'
1683	@echo  '  dir/file.ko     - Build module including final link'
1684	@echo  '  modules_prepare - Set up for building external modules'
1685	@echo  '  tags/TAGS	  - Generate tags file for editors'
1686	@echo  '  cscope	  - Generate cscope index'
1687	@echo  '  gtags           - Generate GNU GLOBAL index'
1688	@echo  '  kernelrelease	  - Output the release version string (use with make -s)'
1689	@echo  '  kernelversion	  - Output the version stored in Makefile (use with make -s)'
1690	@echo  '  image_name	  - Output the image name (use with make -s)'
1691	@echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1692	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1693	 echo  ''
1694	@echo  'Static analysers:'
1695	@echo  '  checkstack      - Generate a list of stack hogs'
1696	@echo  '  versioncheck    - Sanity check on version.h usage'
1697	@echo  '  includecheck    - Check for duplicate included header files'
1698	@echo  '  export_report   - List the usages of all exported symbols'
1699	@echo  '  headerdep       - Detect inclusion cycles in headers'
1700	@echo  '  coccicheck      - Check with Coccinelle'
1701	@echo  '  clang-analyzer  - Check with clang static analyzer'
1702	@echo  '  clang-tidy      - Check with clang-tidy'
1703	@echo  ''
1704	@echo  'Tools:'
1705	@echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1706	@echo  ''
1707	@echo  'Kernel selftest:'
1708	@echo  '  kselftest         - Build and run kernel selftest'
1709	@echo  '                      Build, install, and boot kernel before'
1710	@echo  '                      running kselftest on it'
1711	@echo  '                      Run as root for full coverage'
1712	@echo  '  kselftest-all     - Build kernel selftest'
1713	@echo  '  kselftest-install - Build and install kernel selftest'
1714	@echo  '  kselftest-clean   - Remove all generated kselftest files'
1715	@echo  '  kselftest-merge   - Merge all the config dependencies of'
1716	@echo  '		      kselftest to existing .config.'
1717	@echo  ''
1718	@echo  'Rust targets:'
1719	@echo  '  rustavailable   - Checks whether the Rust toolchain is'
1720	@echo  '		    available and, if not, explains why.'
1721	@echo  '  rustfmt	  - Reformat all the Rust code in the kernel'
1722	@echo  '  rustfmtcheck	  - Checks if all the Rust code in the kernel'
1723	@echo  '		    is formatted, printing a diff otherwise.'
1724	@echo  '  rustdoc	  - Generate Rust documentation'
1725	@echo  '		    (requires kernel .config)'
1726	@echo  '  rusttest        - Runs the Rust tests'
1727	@echo  '                    (requires kernel .config; downloads external repos)'
1728	@echo  '  rust-analyzer	  - Generate rust-project.json rust-analyzer support file'
1729	@echo  '		    (requires kernel .config)'
1730	@echo  '  dir/file.[os]   - Build specified target only'
1731	@echo  '  dir/file.rsi    - Build macro expanded source, similar to C preprocessing.'
1732	@echo  '                    Run with RUSTFMT=n to skip reformatting if needed.'
1733	@echo  '                    The output is not intended to be compilable.'
1734	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1735	@echo  ''
1736	@$(if $(dtstree), \
1737		echo 'Devicetree:'; \
1738		echo '* dtbs             - Build device tree blobs for enabled boards'; \
1739		echo '  dtbs_install     - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1740		echo '  dt_binding_check - Validate device tree binding documents'; \
1741		echo '  dtbs_check       - Validate device tree source files';\
1742		echo '')
1743
1744	@echo 'Userspace tools targets:'
1745	@echo '  use "make tools/help"'
1746	@echo '  or  "cd tools; make help"'
1747	@echo  ''
1748	@echo  'Kernel packaging:'
1749	@$(MAKE) -f $(srctree)/scripts/Makefile.package help
1750	@echo  ''
1751	@echo  'Documentation targets:'
1752	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1753	@echo  ''
1754	@echo  'Architecture specific targets ($(SRCARCH)):'
1755	@$(or $(archhelp),\
1756		echo '  No architecture specific help defined for $(SRCARCH)')
1757	@echo  ''
1758	@$(if $(boards), \
1759		$(foreach b, $(boards), \
1760		printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1761		echo '')
1762	@$(if $(board-dirs), \
1763		$(foreach b, $(board-dirs), \
1764		printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1765		printf "  %-16s - Show all of the above\\n" help-boards; \
1766		echo '')
1767
1768	@echo  '  make V=n   [targets] 1: verbose build'
1769	@echo  '                       2: give reason for rebuild of target'
1770	@echo  '                       V=1 and V=2 can be combined with V=12'
1771	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1772	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1773	@echo  '                       (sparse by default)'
1774	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1775	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1776	@echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
1777	@echo  '		1: warnings which may be relevant and do not occur too often'
1778	@echo  '		2: warnings which occur quite often but may still be relevant'
1779	@echo  '		3: more obscure warnings, can most likely be ignored'
1780	@echo  '		e: warnings are being treated as errors'
1781	@echo  '		Multiple levels can be combined with W=12 or W=123'
1782	@$(if $(dtstree), \
1783		echo '  make CHECK_DTBS=1 [targets] Check all generated dtb files against schema'; \
1784		echo '         This can be applied both to "dtbs" and to individual "foo.dtb" targets' ; \
1785		)
1786	@echo  ''
1787	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
1788	@echo  'For further info see the ./README file'
1789
1790
1791help-board-dirs := $(addprefix help-,$(board-dirs))
1792
1793help-boards: $(help-board-dirs)
1794
1795boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1796
1797$(help-board-dirs): help-%:
1798	@echo  'Architecture specific targets ($(SRCARCH) $*):'
1799	@$(if $(boards-per-dir), \
1800		$(foreach b, $(boards-per-dir), \
1801		printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1802		echo '')
1803
1804
1805# Documentation targets
1806# ---------------------------------------------------------------------------
1807DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1808	       linkcheckdocs dochelp refcheckdocs texinfodocs infodocs
1809PHONY += $(DOC_TARGETS)
1810$(DOC_TARGETS):
1811	$(Q)$(MAKE) $(build)=Documentation $@
1812
1813
1814# Rust targets
1815# ---------------------------------------------------------------------------
1816
1817# "Is Rust available?" target
1818PHONY += rustavailable
1819rustavailable:
1820	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh -v && echo "Rust is available!"
1821
1822# Documentation target
1823#
1824# Using the singular to avoid running afoul of `no-dot-config-targets`.
1825PHONY += rustdoc
1826rustdoc: prepare
1827	$(Q)$(MAKE) $(build)=rust $@
1828
1829# Testing target
1830PHONY += rusttest
1831rusttest: prepare
1832	$(Q)$(MAKE) $(build)=rust $@
1833
1834# Formatting targets
1835PHONY += rustfmt rustfmtcheck
1836
1837# We skip `rust/alloc` since we want to minimize the diff w.r.t. upstream.
1838#
1839# We match using absolute paths since `find` does not resolve them
1840# when matching, which is a problem when e.g. `srctree` is `..`.
1841# We `grep` afterwards in order to remove the directory entry itself.
1842rustfmt:
1843	$(Q)find $(abs_srctree) -type f -name '*.rs' \
1844		-o -path $(abs_srctree)/rust/alloc -prune \
1845		-o -path $(abs_objtree)/rust/test -prune \
1846		| grep -Fv $(abs_srctree)/rust/alloc \
1847		| grep -Fv $(abs_objtree)/rust/test \
1848		| grep -Fv generated \
1849		| xargs $(RUSTFMT) $(rustfmt_flags)
1850
1851rustfmtcheck: rustfmt_flags = --check
1852rustfmtcheck: rustfmt
1853
1854# IDE support targets
1855PHONY += rust-analyzer
1856rust-analyzer:
1857	$(Q)$(MAKE) $(build)=rust $@
1858
1859# Misc
1860# ---------------------------------------------------------------------------
1861
1862PHONY += misc-check
1863misc-check:
1864	$(Q)$(srctree)/scripts/misc-check
1865
1866all: misc-check
1867
1868PHONY += scripts_gdb
1869scripts_gdb: prepare0
1870	$(Q)$(MAKE) $(build)=scripts/gdb
1871	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1872
1873ifdef CONFIG_GDB_SCRIPTS
1874all: scripts_gdb
1875endif
1876
1877else # KBUILD_EXTMOD
1878
1879filechk_kernel.release = echo $(KERNELRELEASE)
1880
1881###
1882# External module support.
1883# When building external modules the kernel used as basis is considered
1884# read-only, and no consistency checks are made and the make
1885# system is not used on the basis kernel. If updates are required
1886# in the basis kernel ordinary make commands (without M=...) must be used.
1887
1888# We are always building only modules.
1889KBUILD_BUILTIN :=
1890KBUILD_MODULES := 1
1891
1892build-dir := $(KBUILD_EXTMOD)
1893
1894compile_commands.json: $(extmod_prefix)compile_commands.json
1895PHONY += compile_commands.json
1896
1897clean-dirs := $(KBUILD_EXTMOD)
1898clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1899	$(KBUILD_EXTMOD)/compile_commands.json $(KBUILD_EXTMOD)/.thinlto-cache
1900
1901PHONY += prepare
1902# now expand this into a simple variable to reduce the cost of shell evaluations
1903prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT)
1904prepare:
1905	@if [ "$(CC_VERSION_TEXT)" != "$(CONFIG_CC_VERSION_TEXT)" ]; then \
1906		echo >&2 "warning: the compiler differs from the one used to build the kernel"; \
1907		echo >&2 "  The kernel was built by: $(CONFIG_CC_VERSION_TEXT)"; \
1908		echo >&2 "  You are using:           $(CC_VERSION_TEXT)"; \
1909	fi
1910
1911PHONY += help
1912help:
1913	@echo  '  Building external modules.'
1914	@echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1915	@echo  ''
1916	@echo  '  modules         - default target, build the module(s)'
1917	@echo  '  modules_install - install the module'
1918	@echo  '  clean           - remove generated files in module directory only'
1919	@echo  ''
1920
1921__external_modules_error:
1922	@echo >&2 '***'
1923	@echo >&2 '*** The present kernel disabled CONFIG_MODULES.'
1924	@echo >&2 '*** You cannot build or install external modules.'
1925	@echo >&2 '***'
1926	@false
1927
1928endif # KBUILD_EXTMOD
1929
1930# ---------------------------------------------------------------------------
1931# Modules
1932
1933PHONY += modules modules_install modules_prepare
1934
1935ifdef CONFIG_MODULES
1936
1937$(MODORDER): $(build-dir)
1938	@:
1939
1940# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
1941# This is solely useful to speed up test compiles.
1942modules: modpost
1943ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1944	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1945endif
1946
1947PHONY += modules_check
1948modules_check: $(MODORDER)
1949	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1950
1951quiet_cmd_depmod = DEPMOD  $(MODLIB)
1952      cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1953                   $(KERNELRELEASE)
1954
1955modules_install:
1956	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1957	$(call cmd,depmod)
1958
1959else # CONFIG_MODULES
1960
1961# Modules not configured
1962# ---------------------------------------------------------------------------
1963
1964PHONY += __external_modules_error
1965
1966modules modules_install: __external_modules_error
1967	@:
1968
1969KBUILD_MODULES :=
1970
1971endif # CONFIG_MODULES
1972
1973PHONY += modpost
1974modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \
1975	 $(if $(KBUILD_MODULES), modules_check)
1976	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1977
1978# Single targets
1979# ---------------------------------------------------------------------------
1980# To build individual files in subdirectories, you can do like this:
1981#
1982#   make foo/bar/baz.s
1983#
1984# The supported suffixes for single-target are listed in 'single-targets'
1985#
1986# To build only under specific subdirectories, you can do like this:
1987#
1988#   make foo/bar/baz/
1989
1990ifdef single-build
1991
1992# .ko is special because modpost is needed
1993single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1994single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \
1995		$(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko)))
1996
1997$(single-ko): single_modules
1998	@:
1999$(single-no-ko): $(build-dir)
2000	@:
2001
2002# Remove MODORDER when done because it is not the real one.
2003PHONY += single_modules
2004single_modules: $(single-no-ko) modules_prepare
2005	$(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$(m:%.ko=%.o);) } > $(MODORDER)
2006	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
2007ifneq ($(KBUILD_MODPOST_NOFINAL),1)
2008	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
2009endif
2010	$(Q)rm -f $(MODORDER)
2011
2012single-goals := $(addprefix $(build-dir)/, $(single-no-ko))
2013
2014KBUILD_MODULES := 1
2015
2016endif
2017
2018# Preset locale variables to speed up the build process. Limit locale
2019# tweaks to this spot to avoid wrong language settings when running
2020# make menuconfig etc.
2021# Error messages still appears in the original language
2022PHONY += $(build-dir)
2023$(build-dir): prepare
2024	$(Q)$(MAKE) $(build)=$@ need-builtin=1 need-modorder=1 $(single-goals)
2025
2026clean-dirs := $(addprefix _clean_, $(clean-dirs))
2027PHONY += $(clean-dirs) clean
2028$(clean-dirs):
2029	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
2030
2031clean: $(clean-dirs)
2032	$(call cmd,rmfiles)
2033	@find $(or $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
2034		\( -name '*.[aios]' -o -name '*.rsi' -o -name '*.ko' -o -name '.*.cmd' \
2035		-o -name '*.ko.*' \
2036		-o -name '*.dtb' -o -name '*.dtbo' \
2037		-o -name '*.dtb.S' -o -name '*.dtbo.S' \
2038		-o -name '*.dt.yaml' \
2039		-o -name '*.dwo' -o -name '*.lst' \
2040		-o -name '*.su' -o -name '*.mod' \
2041		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
2042		-o -name '*.lex.c' -o -name '*.tab.[ch]' \
2043		-o -name '*.asn1.[ch]' \
2044		-o -name '*.symtypes' -o -name 'modules.order' \
2045		-o -name '*.c.[012]*.*' \
2046		-o -name '*.ll' \
2047		-o -name '*.gcno' \
2048		-o -name '*.*.symversions' \) -type f -print \
2049		-o -name '.tmp_*' -print \
2050		| xargs rm -rf
2051
2052# Generate tags for editors
2053# ---------------------------------------------------------------------------
2054quiet_cmd_tags = GEN     $@
2055      cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
2056
2057tags TAGS cscope gtags: FORCE
2058	$(call cmd,tags)
2059
2060# Script to generate missing namespace dependencies
2061# ---------------------------------------------------------------------------
2062
2063PHONY += nsdeps
2064nsdeps: export KBUILD_NSDEPS=1
2065nsdeps: modules
2066	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
2067
2068# Clang Tooling
2069# ---------------------------------------------------------------------------
2070
2071quiet_cmd_gen_compile_commands = GEN     $@
2072      cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
2073
2074$(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
2075	$(if $(KBUILD_EXTMOD),, vmlinux.a $(KBUILD_VMLINUX_LIBS)) \
2076	$(if $(CONFIG_MODULES), $(MODORDER)) FORCE
2077	$(call if_changed,gen_compile_commands)
2078
2079targets += $(extmod_prefix)compile_commands.json
2080
2081PHONY += clang-tidy clang-analyzer
2082
2083ifdef CONFIG_CC_IS_CLANG
2084quiet_cmd_clang_tools = CHECK   $<
2085      cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
2086
2087clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
2088	$(call cmd,clang_tools)
2089else
2090clang-tidy clang-analyzer:
2091	@echo "$@ requires CC=clang" >&2
2092	@false
2093endif
2094
2095# Scripts to check various things for consistency
2096# ---------------------------------------------------------------------------
2097
2098PHONY += includecheck versioncheck coccicheck export_report
2099
2100includecheck:
2101	find $(srctree)/* $(RCS_FIND_IGNORE) \
2102		-name '*.[hcS]' -type f -print | sort \
2103		| xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
2104
2105versioncheck:
2106	find $(srctree)/* $(RCS_FIND_IGNORE) \
2107		-name '*.[hcS]' -type f -print | sort \
2108		| xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
2109
2110coccicheck:
2111	$(Q)$(BASH) $(srctree)/scripts/$@
2112
2113export_report:
2114	$(PERL) $(srctree)/scripts/export_report.pl
2115
2116PHONY += checkstack kernelrelease kernelversion image_name
2117
2118# UML needs a little special treatment here.  It wants to use the host
2119# toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
2120# else wants $(ARCH), including people doing cross-builds, which means
2121# that $(SUBARCH) doesn't work here.
2122ifeq ($(ARCH), um)
2123CHECKSTACK_ARCH := $(SUBARCH)
2124else
2125CHECKSTACK_ARCH := $(ARCH)
2126endif
2127checkstack:
2128	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
2129	$(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
2130
2131kernelrelease:
2132	@$(filechk_kernel.release)
2133
2134kernelversion:
2135	@echo $(KERNELVERSION)
2136
2137image_name:
2138	@echo $(KBUILD_IMAGE)
2139
2140quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
2141      cmd_rmfiles = rm -rf $(rm-files)
2142
2143# read saved command lines for existing targets
2144existing-targets := $(wildcard $(sort $(targets)))
2145
2146-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
2147
2148endif # config-build
2149endif # mixed-build
2150endif # need-sub-make
2151
2152PHONY += FORCE
2153FORCE:
2154
2155# Declare the contents of the PHONY variable as phony.  We keep that
2156# information in a variable so we can use it in if_changed and friends.
2157.PHONY: $(PHONY)
2158