xref: /openbmc/linux/Makefile (revision d6e2d652)
1# SPDX-License-Identifier: GPL-2.0
2VERSION = 6
3PATCHLEVEL = 5
4SUBLEVEL = 0
5EXTRAVERSION = -rc4
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
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			    -Wclippy::dbg_macro
471
472KBUILD_HOSTCFLAGS   := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
473KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
474KBUILD_HOSTRUSTFLAGS := $(rust_common_flags) -O -Cstrip=debuginfo \
475			-Zallow-features= $(HOSTRUSTFLAGS)
476KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
477KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
478
479# Make variables (CC, etc...)
480CPP		= $(CC) -E
481ifneq ($(LLVM),)
482CC		= $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
483LD		= $(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX)
484AR		= $(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX)
485NM		= $(LLVM_PREFIX)llvm-nm$(LLVM_SUFFIX)
486OBJCOPY		= $(LLVM_PREFIX)llvm-objcopy$(LLVM_SUFFIX)
487OBJDUMP		= $(LLVM_PREFIX)llvm-objdump$(LLVM_SUFFIX)
488READELF		= $(LLVM_PREFIX)llvm-readelf$(LLVM_SUFFIX)
489STRIP		= $(LLVM_PREFIX)llvm-strip$(LLVM_SUFFIX)
490else
491CC		= $(CROSS_COMPILE)gcc
492LD		= $(CROSS_COMPILE)ld
493AR		= $(CROSS_COMPILE)ar
494NM		= $(CROSS_COMPILE)nm
495OBJCOPY		= $(CROSS_COMPILE)objcopy
496OBJDUMP		= $(CROSS_COMPILE)objdump
497READELF		= $(CROSS_COMPILE)readelf
498STRIP		= $(CROSS_COMPILE)strip
499endif
500RUSTC		= rustc
501RUSTDOC		= rustdoc
502RUSTFMT		= rustfmt
503CLIPPY_DRIVER	= clippy-driver
504BINDGEN		= bindgen
505CARGO		= cargo
506PAHOLE		= pahole
507RESOLVE_BTFIDS	= $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
508LEX		= flex
509YACC		= bison
510AWK		= awk
511INSTALLKERNEL  := installkernel
512DEPMOD		= depmod
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
566KBUILD_CFLAGS += -Wall
567KBUILD_CFLAGS += -Wundef
568KBUILD_CFLAGS += -Werror=implicit-function-declaration
569KBUILD_CFLAGS += -Werror=implicit-int
570KBUILD_CFLAGS += -Werror=return-type
571KBUILD_CFLAGS += -Werror=strict-prototypes
572KBUILD_CFLAGS += -Wno-format-security
573KBUILD_CFLAGS += -Wno-trigraphs
574
575KBUILD_CPPFLAGS := -D__KERNEL__
576KBUILD_RUSTFLAGS := $(rust_common_flags) \
577		    --target=$(objtree)/scripts/target.json \
578		    -Cpanic=abort -Cembed-bitcode=n -Clto=n \
579		    -Cforce-unwind-tables=n -Ccodegen-units=1 \
580		    -Csymbol-mangling-version=v0 \
581		    -Crelocation-model=static \
582		    -Zfunction-sections=n \
583		    -Dclippy::float_arithmetic
584
585KBUILD_AFLAGS_KERNEL :=
586KBUILD_CFLAGS_KERNEL :=
587KBUILD_RUSTFLAGS_KERNEL :=
588KBUILD_AFLAGS_MODULE  := -DMODULE
589KBUILD_CFLAGS_MODULE  := -DMODULE
590KBUILD_RUSTFLAGS_MODULE := --cfg MODULE
591KBUILD_LDFLAGS_MODULE :=
592KBUILD_LDFLAGS :=
593CLANG_FLAGS :=
594
595ifeq ($(KBUILD_CLIPPY),1)
596	RUSTC_OR_CLIPPY_QUIET := CLIPPY
597	RUSTC_OR_CLIPPY = $(CLIPPY_DRIVER)
598else
599	RUSTC_OR_CLIPPY_QUIET := RUSTC
600	RUSTC_OR_CLIPPY = $(RUSTC)
601endif
602
603ifdef RUST_LIB_SRC
604	export RUST_LIB_SRC
605endif
606
607# Allows the usage of unstable features in stable compilers.
608export RUSTC_BOOTSTRAP := 1
609
610export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG
611export RUSTC RUSTDOC RUSTFMT RUSTC_OR_CLIPPY_QUIET RUSTC_OR_CLIPPY BINDGEN CARGO
612export HOSTRUSTC KBUILD_HOSTRUSTFLAGS
613export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
614export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
615export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
616export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
617export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS
618
619export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
620export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
621export KBUILD_RUSTFLAGS RUSTFLAGS_KERNEL RUSTFLAGS_MODULE
622export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
623export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_RUSTFLAGS_MODULE KBUILD_LDFLAGS_MODULE
624export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL KBUILD_RUSTFLAGS_KERNEL
625export PAHOLE_FLAGS
626
627# Files to ignore in find ... statements
628
629export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
630			  -name CVS -o -name .pc -o -name .hg -o -name .git \) \
631			  -prune -o
632export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
633			 --exclude CVS --exclude .pc --exclude .hg --exclude .git
634
635# ===========================================================================
636# Rules shared between *config targets and build targets
637
638# Basic helpers built in scripts/basic/
639PHONY += scripts_basic
640scripts_basic:
641	$(Q)$(MAKE) $(build)=scripts/basic
642
643PHONY += outputmakefile
644ifdef building_out_of_srctree
645# Before starting out-of-tree build, make sure the source tree is clean.
646# outputmakefile generates a Makefile in the output directory, if using a
647# separate output directory. This allows convenient use of make in the
648# output directory.
649# At the same time when output Makefile generated, generate .gitignore to
650# ignore whole output directory
651
652quiet_cmd_makefile = GEN     Makefile
653      cmd_makefile = { \
654	echo "\# Automatically generated by $(srctree)/Makefile: don't edit"; \
655	echo "include $(srctree)/Makefile"; \
656	} > Makefile
657
658outputmakefile:
659	@if [ -f $(srctree)/.config -o \
660		 -d $(srctree)/include/config -o \
661		 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
662		echo >&2 "***"; \
663		echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
664		echo >&2 "*** in $(abs_srctree)";\
665		echo >&2 "***"; \
666		false; \
667	fi
668	$(Q)ln -fsn $(srctree) source
669	$(call cmd,makefile)
670	$(Q)test -e .gitignore || \
671	{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
672endif
673
674# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
675# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
676# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
677# and from include/config/auto.conf.cmd to detect the compiler upgrade.
678CC_VERSION_TEXT = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1))
679
680ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
681include $(srctree)/scripts/Makefile.clang
682endif
683
684# Include this also for config targets because some architectures need
685# cc-cross-prefix to determine CROSS_COMPILE.
686ifdef need-compiler
687include $(srctree)/scripts/Makefile.compiler
688endif
689
690ifdef config-build
691# ===========================================================================
692# *config targets only - make sure prerequisites are updated, and descend
693# in scripts/kconfig to make the *config target
694
695# Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
696# KBUILD_DEFCONFIG may point out an alternative default configuration
697# used for 'make defconfig'
698include $(srctree)/arch/$(SRCARCH)/Makefile
699export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
700
701config: outputmakefile scripts_basic FORCE
702	$(Q)$(MAKE) $(build)=scripts/kconfig $@
703
704%config: outputmakefile scripts_basic FORCE
705	$(Q)$(MAKE) $(build)=scripts/kconfig $@
706
707else #!config-build
708# ===========================================================================
709# Build targets only - this includes vmlinux, arch specific targets, clean
710# targets and others. In general all targets except *config targets.
711
712# If building an external module we do not care about the all: rule
713# but instead __all depend on modules
714PHONY += all
715ifeq ($(KBUILD_EXTMOD),)
716__all: all
717else
718__all: modules
719endif
720
721targets :=
722
723# Decide whether to build built-in, modular, or both.
724# Normally, just do built-in.
725
726KBUILD_MODULES :=
727KBUILD_BUILTIN := 1
728
729# If we have only "make modules", don't compile built-in objects.
730ifeq ($(MAKECMDGOALS),modules)
731  KBUILD_BUILTIN :=
732endif
733
734# If we have "make <whatever> modules", compile modules
735# in addition to whatever we do anyway.
736# Just "make" or "make all" shall build modules as well
737
738ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
739  KBUILD_MODULES := 1
740endif
741
742ifeq ($(MAKECMDGOALS),)
743  KBUILD_MODULES := 1
744endif
745
746export KBUILD_MODULES KBUILD_BUILTIN
747
748ifdef need-config
749include include/config/auto.conf
750endif
751
752ifeq ($(KBUILD_EXTMOD),)
753# Objects we will link into vmlinux / subdirs we need to visit
754core-y		:=
755drivers-y	:=
756libs-y		:= lib/
757endif # KBUILD_EXTMOD
758
759# The all: target is the default when no target is given on the
760# command line.
761# This allow a user to issue only 'make' to build a kernel including modules
762# Defaults to vmlinux, but the arch makefile usually adds further targets
763all: vmlinux
764
765CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage
766ifdef CONFIG_CC_IS_GCC
767CFLAGS_GCOV	+= -fno-tree-loop-im
768endif
769export CFLAGS_GCOV
770
771# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
772ifdef CONFIG_FUNCTION_TRACER
773  CC_FLAGS_FTRACE := -pg
774endif
775
776include $(srctree)/arch/$(SRCARCH)/Makefile
777
778ifdef need-config
779ifdef may-sync-config
780# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
781# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
782# because some architectures define CROSS_COMPILE there.
783include include/config/auto.conf.cmd
784
785$(KCONFIG_CONFIG):
786	@echo >&2 '***'
787	@echo >&2 '*** Configuration file "$@" not found!'
788	@echo >&2 '***'
789	@echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
790	@echo >&2 '*** "make menuconfig" or "make xconfig").'
791	@echo >&2 '***'
792	@/bin/false
793
794# The actual configuration files used during the build are stored in
795# include/generated/ and include/config/. Update them if .config is newer than
796# include/config/auto.conf (which mirrors .config).
797#
798# This exploits the 'multi-target pattern rule' trick.
799# The syncconfig should be executed only once to make all the targets.
800# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
801#
802# Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
803# so you cannot notice that Kconfig is waiting for the user input.
804%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h %/generated/rustc_cfg: $(KCONFIG_CONFIG)
805	$(Q)$(kecho) "  SYNC    $@"
806	$(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
807else # !may-sync-config
808# External modules and some install targets need include/generated/autoconf.h
809# and include/config/auto.conf but do not care if they are up-to-date.
810# Use auto.conf to trigger the test
811PHONY += include/config/auto.conf
812
813include/config/auto.conf:
814	@test -e include/generated/autoconf.h -a -e $@ || (		\
815	echo >&2;							\
816	echo >&2 "  ERROR: Kernel configuration is invalid.";		\
817	echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
818	echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";	\
819	echo >&2 ;							\
820	/bin/false)
821
822endif # may-sync-config
823endif # need-config
824
825KBUILD_CFLAGS	+= -fno-delete-null-pointer-checks
826KBUILD_CFLAGS	+= $(call cc-disable-warning,frame-address,)
827KBUILD_CFLAGS	+= $(call cc-disable-warning, format-truncation)
828KBUILD_CFLAGS	+= $(call cc-disable-warning, format-overflow)
829KBUILD_CFLAGS	+= $(call cc-disable-warning, address-of-packed-member)
830
831ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
832KBUILD_CFLAGS += -O2
833KBUILD_RUSTFLAGS += -Copt-level=2
834else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
835KBUILD_CFLAGS += -Os
836KBUILD_RUSTFLAGS += -Copt-level=s
837endif
838
839# Always set `debug-assertions` and `overflow-checks` because their default
840# depends on `opt-level` and `debug-assertions`, respectively.
841KBUILD_RUSTFLAGS += -Cdebug-assertions=$(if $(CONFIG_RUST_DEBUG_ASSERTIONS),y,n)
842KBUILD_RUSTFLAGS += -Coverflow-checks=$(if $(CONFIG_RUST_OVERFLOW_CHECKS),y,n)
843
844# Tell gcc to never replace conditional load with a non-conditional one
845ifdef CONFIG_CC_IS_GCC
846# gcc-10 renamed --param=allow-store-data-races=0 to
847# -fno-allow-store-data-races.
848KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
849KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
850endif
851
852ifdef CONFIG_READABLE_ASM
853# Disable optimizations that make assembler listings hard to read.
854# reorder blocks reorders the control in the function
855# ipa clone creates specialized cloned functions
856# partial inlining inlines only parts of functions
857KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
858endif
859
860ifneq ($(CONFIG_FRAME_WARN),0)
861KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
862endif
863
864stackp-flags-y                                    := -fno-stack-protector
865stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
866stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
867
868KBUILD_CFLAGS += $(stackp-flags-y)
869
870KBUILD_CPPFLAGS-$(CONFIG_WERROR) += -Werror
871KBUILD_CPPFLAGS += $(KBUILD_CPPFLAGS-y)
872KBUILD_CFLAGS-$(CONFIG_CC_NO_ARRAY_BOUNDS) += -Wno-array-bounds
873
874KBUILD_RUSTFLAGS-$(CONFIG_WERROR) += -Dwarnings
875KBUILD_RUSTFLAGS += $(KBUILD_RUSTFLAGS-y)
876
877ifdef CONFIG_CC_IS_CLANG
878# The kernel builds with '-std=gnu11' so use of GNU extensions is acceptable.
879KBUILD_CFLAGS += -Wno-gnu
880else
881
882# gcc inanely warns about local variables called 'main'
883KBUILD_CFLAGS += -Wno-main
884endif
885
886# These warnings generated too much noise in a regular build.
887# Use make W=1 to enable them (see scripts/Makefile.extrawarn)
888KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
889KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
890
891# These result in bogus false positives
892KBUILD_CFLAGS += $(call cc-disable-warning, dangling-pointer)
893
894ifdef CONFIG_FRAME_POINTER
895KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
896KBUILD_RUSTFLAGS += -Cforce-frame-pointers=y
897else
898# Some targets (ARM with Thumb2, for example), can't be built with frame
899# pointers.  For those, we don't have FUNCTION_TRACER automatically
900# select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
901# incompatible with -fomit-frame-pointer with current GCC, so we don't use
902# -fomit-frame-pointer with FUNCTION_TRACER.
903# In the Rust target specification, "frame-pointer" is set explicitly
904# to "may-omit".
905ifndef CONFIG_FUNCTION_TRACER
906KBUILD_CFLAGS	+= -fomit-frame-pointer
907endif
908endif
909
910# Initialize all stack variables with a 0xAA pattern.
911ifdef CONFIG_INIT_STACK_ALL_PATTERN
912KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
913endif
914
915# Initialize all stack variables with a zero value.
916ifdef CONFIG_INIT_STACK_ALL_ZERO
917KBUILD_CFLAGS	+= -ftrivial-auto-var-init=zero
918ifdef CONFIG_CC_HAS_AUTO_VAR_INIT_ZERO_ENABLER
919# https://github.com/llvm/llvm-project/issues/44842
920CC_AUTO_VAR_INIT_ZERO_ENABLER := -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
921export CC_AUTO_VAR_INIT_ZERO_ENABLER
922KBUILD_CFLAGS	+= $(CC_AUTO_VAR_INIT_ZERO_ENABLER)
923endif
924endif
925
926# While VLAs have been removed, GCC produces unreachable stack probes
927# for the randomize_kstack_offset feature. Disable it for all compilers.
928KBUILD_CFLAGS	+= $(call cc-option, -fno-stack-clash-protection)
929
930# Clear used registers at func exit (to reduce data lifetime and ROP gadgets).
931ifdef CONFIG_ZERO_CALL_USED_REGS
932KBUILD_CFLAGS	+= -fzero-call-used-regs=used-gpr
933endif
934
935ifdef CONFIG_FUNCTION_TRACER
936ifdef CONFIG_FTRACE_MCOUNT_USE_CC
937  CC_FLAGS_FTRACE	+= -mrecord-mcount
938  ifdef CONFIG_HAVE_NOP_MCOUNT
939    ifeq ($(call cc-option-yn, -mnop-mcount),y)
940      CC_FLAGS_FTRACE	+= -mnop-mcount
941      CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
942    endif
943  endif
944endif
945ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
946  ifdef CONFIG_HAVE_OBJTOOL_NOP_MCOUNT
947    CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
948  endif
949endif
950ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
951  ifdef CONFIG_HAVE_C_RECORDMCOUNT
952    BUILD_C_RECORDMCOUNT := y
953    export BUILD_C_RECORDMCOUNT
954  endif
955endif
956ifdef CONFIG_HAVE_FENTRY
957  # s390-linux-gnu-gcc did not support -mfentry until gcc-9.
958  ifeq ($(call cc-option-yn, -mfentry),y)
959    CC_FLAGS_FTRACE	+= -mfentry
960    CC_FLAGS_USING	+= -DCC_USING_FENTRY
961  endif
962endif
963export CC_FLAGS_FTRACE
964KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
965KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
966endif
967
968# We trigger additional mismatches with less inlining
969ifdef CONFIG_DEBUG_SECTION_MISMATCH
970KBUILD_CFLAGS += -fno-inline-functions-called-once
971endif
972
973# `rustc`'s `-Zfunction-sections` applies to data too (as of 1.59.0).
974ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
975KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
976KBUILD_RUSTFLAGS_KERNEL += -Zfunction-sections=y
977LDFLAGS_vmlinux += --gc-sections
978endif
979
980ifdef CONFIG_SHADOW_CALL_STACK
981ifndef CONFIG_DYNAMIC_SCS
982CC_FLAGS_SCS	:= -fsanitize=shadow-call-stack
983KBUILD_CFLAGS	+= $(CC_FLAGS_SCS)
984endif
985export CC_FLAGS_SCS
986endif
987
988ifdef CONFIG_LTO_CLANG
989ifdef CONFIG_LTO_CLANG_THIN
990CC_FLAGS_LTO	:= -flto=thin -fsplit-lto-unit
991KBUILD_LDFLAGS	+= --thinlto-cache-dir=$(extmod_prefix).thinlto-cache
992else
993CC_FLAGS_LTO	:= -flto
994endif
995CC_FLAGS_LTO	+= -fvisibility=hidden
996
997# Limit inlining across translation units to reduce binary size
998KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
999
1000# Check for frame size exceeding threshold during prolog/epilog insertion
1001# when using lld < 13.0.0.
1002ifneq ($(CONFIG_FRAME_WARN),0)
1003ifeq ($(call test-lt, $(CONFIG_LLD_VERSION), 130000),y)
1004KBUILD_LDFLAGS	+= -plugin-opt=-warn-stack-size=$(CONFIG_FRAME_WARN)
1005endif
1006endif
1007endif
1008
1009ifdef CONFIG_LTO
1010KBUILD_CFLAGS	+= -fno-lto $(CC_FLAGS_LTO)
1011KBUILD_AFLAGS	+= -fno-lto
1012export CC_FLAGS_LTO
1013endif
1014
1015ifdef CONFIG_CFI_CLANG
1016CC_FLAGS_CFI	:= -fsanitize=kcfi
1017KBUILD_CFLAGS	+= $(CC_FLAGS_CFI)
1018export CC_FLAGS_CFI
1019endif
1020
1021ifneq ($(CONFIG_FUNCTION_ALIGNMENT),0)
1022KBUILD_CFLAGS += -falign-functions=$(CONFIG_FUNCTION_ALIGNMENT)
1023endif
1024
1025# arch Makefile may override CC so keep this after arch Makefile is included
1026NOSTDINC_FLAGS += -nostdinc
1027
1028# Variable Length Arrays (VLAs) should not be used anywhere in the kernel
1029KBUILD_CFLAGS += -Wvla
1030
1031# disable pointer signed / unsigned warnings in gcc 4.0
1032KBUILD_CFLAGS += -Wno-pointer-sign
1033
1034# In order to make sure new function cast mismatches are not introduced
1035# in the kernel (to avoid tripping CFI checking), the kernel should be
1036# globally built with -Wcast-function-type.
1037KBUILD_CFLAGS += $(call cc-option, -Wcast-function-type)
1038
1039# To gain proper coverage for CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE,
1040# the kernel uses only C99 flexible arrays for dynamically sized trailing
1041# arrays. Enforce this for everything that may examine structure sizes and
1042# perform bounds checking.
1043KBUILD_CFLAGS += $(call cc-option, -fstrict-flex-arrays=3)
1044
1045# disable stringop warnings in gcc 8+
1046KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
1047
1048# We'll want to enable this eventually, but it's not going away for 5.7 at least
1049KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
1050
1051# Another good warning that we'll want to enable eventually
1052KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
1053
1054# Enabled with W=2, disabled by default as noisy
1055ifdef CONFIG_CC_IS_GCC
1056KBUILD_CFLAGS += -Wno-maybe-uninitialized
1057endif
1058
1059# The allocators already balk at large sizes, so silence the compiler
1060# warnings for bounds checks involving those possible values. While
1061# -Wno-alloc-size-larger-than would normally be used here, earlier versions
1062# of gcc (<9.1) weirdly don't handle the option correctly when _other_
1063# warnings are produced (?!). Using -Walloc-size-larger-than=SIZE_MAX
1064# doesn't work (as it is documented to), silently resolving to "0" prior to
1065# version 9.1 (and producing an error more recently). Numeric values larger
1066# than PTRDIFF_MAX also don't work prior to version 9.1, which are silently
1067# ignored, continuing to default to PTRDIFF_MAX. So, left with no other
1068# choice, we must perform a versioned check to disable this warning.
1069# https://lore.kernel.org/lkml/20210824115859.187f272f@canb.auug.org.au
1070KBUILD_CFLAGS-$(call gcc-min-version, 90100) += -Wno-alloc-size-larger-than
1071KBUILD_CFLAGS += $(KBUILD_CFLAGS-y) $(CONFIG_CC_IMPLICIT_FALLTHROUGH)
1072
1073# disable invalid "can't wrap" optimizations for signed / pointers
1074KBUILD_CFLAGS	+= -fno-strict-overflow
1075
1076# Make sure -fstack-check isn't enabled (like gentoo apparently did)
1077KBUILD_CFLAGS  += -fno-stack-check
1078
1079# conserve stack if available
1080ifdef CONFIG_CC_IS_GCC
1081KBUILD_CFLAGS   += -fconserve-stack
1082endif
1083
1084# Prohibit date/time macros, which would make the build non-deterministic
1085KBUILD_CFLAGS   += -Werror=date-time
1086
1087# enforce correct pointer usage
1088KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)
1089
1090# Require designated initializers for all marked structures
1091KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)
1092
1093# change __FILE__ to the relative path from the srctree
1094KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
1095
1096# include additional Makefiles when needed
1097include-y			:= scripts/Makefile.extrawarn
1098include-$(CONFIG_DEBUG_INFO)	+= scripts/Makefile.debug
1099include-$(CONFIG_KASAN)		+= scripts/Makefile.kasan
1100include-$(CONFIG_KCSAN)		+= scripts/Makefile.kcsan
1101include-$(CONFIG_KMSAN)		+= scripts/Makefile.kmsan
1102include-$(CONFIG_UBSAN)		+= scripts/Makefile.ubsan
1103include-$(CONFIG_KCOV)		+= scripts/Makefile.kcov
1104include-$(CONFIG_RANDSTRUCT)	+= scripts/Makefile.randstruct
1105include-$(CONFIG_GCC_PLUGINS)	+= scripts/Makefile.gcc-plugins
1106
1107include $(addprefix $(srctree)/, $(include-y))
1108
1109# scripts/Makefile.gcc-plugins is intentionally included last.
1110# Do not add $(call cc-option,...) below this line. When you build the kernel
1111# from the clean source tree, the GCC plugins do not exist at this point.
1112
1113# Add user supplied CPPFLAGS, AFLAGS, CFLAGS and RUSTFLAGS as the last assignments
1114KBUILD_CPPFLAGS += $(KCPPFLAGS)
1115KBUILD_AFLAGS   += $(KAFLAGS)
1116KBUILD_CFLAGS   += $(KCFLAGS)
1117KBUILD_RUSTFLAGS += $(KRUSTFLAGS)
1118
1119KBUILD_LDFLAGS_MODULE += --build-id=sha1
1120LDFLAGS_vmlinux += --build-id=sha1
1121
1122KBUILD_LDFLAGS	+= -z noexecstack
1123ifeq ($(CONFIG_LD_IS_BFD),y)
1124KBUILD_LDFLAGS	+= $(call ld-option,--no-warn-rwx-segments)
1125endif
1126
1127ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1128LDFLAGS_vmlinux	+= -X
1129endif
1130
1131ifeq ($(CONFIG_RELR),y)
1132# ld.lld before 15 did not support -z pack-relative-relocs.
1133LDFLAGS_vmlinux	+= $(call ld-option,--pack-dyn-relocs=relr,-z pack-relative-relocs)
1134endif
1135
1136# We never want expected sections to be placed heuristically by the
1137# linker. All sections should be explicitly named in the linker script.
1138ifdef CONFIG_LD_ORPHAN_WARN
1139LDFLAGS_vmlinux += --orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL)
1140endif
1141
1142# Align the bit size of userspace programs with the kernel
1143KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1144KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1145
1146# make the checker run with the right architecture
1147CHECKFLAGS += --arch=$(ARCH)
1148
1149# insure the checker run with the right endianness
1150CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1151
1152# the checker needs the correct machine size
1153CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1154
1155# Default kernel image to build when no specific target is given.
1156# KBUILD_IMAGE may be overruled on the command line or
1157# set in the environment
1158# Also any assignments in arch/$(ARCH)/Makefile take precedence over
1159# this default value
1160export KBUILD_IMAGE ?= vmlinux
1161
1162#
1163# INSTALL_PATH specifies where to place the updated kernel and system map
1164# images. Default is /boot, but you can set it to other values
1165export	INSTALL_PATH ?= /boot
1166
1167#
1168# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1169# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1170# an argument if needed. Otherwise it defaults to the kernel install path
1171#
1172export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1173
1174#
1175# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1176# relocations required by build roots.  This is not defined in the
1177# makefile but the argument can be passed to make if needed.
1178#
1179
1180MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1181export MODLIB
1182
1183PHONY += prepare0
1184
1185export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
1186export MODORDER := $(extmod_prefix)modules.order
1187export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
1188
1189ifeq ($(KBUILD_EXTMOD),)
1190
1191build-dir	:= .
1192clean-dirs	:= $(sort . Documentation \
1193		     $(patsubst %/,%,$(filter %/, $(core-) \
1194			$(drivers-) $(libs-))))
1195
1196export ARCH_CORE	:= $(core-y)
1197export ARCH_LIB		:= $(filter %/, $(libs-y))
1198export ARCH_DRIVERS	:= $(drivers-y) $(drivers-m)
1199# Externally visible symbols (used by link-vmlinux.sh)
1200
1201KBUILD_VMLINUX_OBJS := ./built-in.a
1202ifdef CONFIG_MODULES
1203KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1204KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1205else
1206KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1207endif
1208
1209export KBUILD_VMLINUX_LIBS
1210export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1211
1212ifdef CONFIG_TRIM_UNUSED_KSYMS
1213# For the kernel to actually contain only the needed exported symbols,
1214# we have to build modules as well to determine what those symbols are.
1215KBUILD_MODULES := 1
1216endif
1217
1218# '$(AR) mPi' needs 'T' to workaround the bug of llvm-ar <= 14
1219quiet_cmd_ar_vmlinux.a = AR      $@
1220      cmd_ar_vmlinux.a = \
1221	rm -f $@; \
1222	$(AR) cDPrST $@ $(KBUILD_VMLINUX_OBJS); \
1223	$(AR) mPiT $$($(AR) t $@ | sed -n 1p) $@ $$($(AR) t $@ | grep -F -f $(srctree)/scripts/head-object-list.txt)
1224
1225targets += vmlinux.a
1226vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt FORCE
1227	$(call if_changed,ar_vmlinux.a)
1228
1229PHONY += vmlinux_o
1230vmlinux_o: vmlinux.a $(KBUILD_VMLINUX_LIBS)
1231	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o
1232
1233vmlinux.o modules.builtin.modinfo modules.builtin: vmlinux_o
1234	@:
1235
1236PHONY += vmlinux
1237# LDFLAGS_vmlinux in the top Makefile defines linker flags for the top vmlinux,
1238# not for decompressors. LDFLAGS_vmlinux in arch/*/boot/compressed/Makefile is
1239# unrelated; the decompressors just happen to have the same base name,
1240# arch/*/boot/compressed/vmlinux.
1241# Export LDFLAGS_vmlinux only to scripts/Makefile.vmlinux.
1242#
1243# _LDFLAGS_vmlinux is a workaround for the 'private export' bug:
1244#   https://savannah.gnu.org/bugs/?61463
1245# For Make > 4.4, the following simple code will work:
1246#  vmlinux: private export LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1247vmlinux: private _LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1248vmlinux: export LDFLAGS_vmlinux = $(_LDFLAGS_vmlinux)
1249vmlinux: vmlinux.o $(KBUILD_LDS) modpost
1250	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux
1251
1252# The actual objects are generated when descending,
1253# make sure no implicit rule kicks in
1254$(sort $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)): . ;
1255
1256ifeq ($(origin KERNELRELEASE),file)
1257filechk_kernel.release = $(srctree)/scripts/setlocalversion $(srctree)
1258else
1259filechk_kernel.release = echo $(KERNELRELEASE)
1260endif
1261
1262# Store (new) KERNELRELEASE string in include/config/kernel.release
1263include/config/kernel.release: FORCE
1264	$(call filechk,kernel.release)
1265
1266# Additional helpers built in scripts/
1267# Carefully list dependencies so we do not try to build scripts twice
1268# in parallel
1269PHONY += scripts
1270scripts: scripts_basic scripts_dtc
1271	$(Q)$(MAKE) $(build)=$(@)
1272
1273# Things we need to do before we recursively start building the kernel
1274# or the modules are listed in "prepare".
1275# A multi level approach is used. prepareN is processed before prepareN-1.
1276# archprepare is used in arch Makefiles and when processed asm symlink,
1277# version.h and scripts_basic is processed / created.
1278
1279PHONY += prepare archprepare
1280
1281archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1282	asm-generic $(version_h) include/generated/utsrelease.h \
1283	include/generated/compile.h include/generated/autoconf.h remove-stale-files
1284
1285prepare0: archprepare
1286	$(Q)$(MAKE) $(build)=scripts/mod
1287	$(Q)$(MAKE) $(build)=. prepare
1288
1289# All the preparing..
1290prepare: prepare0
1291ifdef CONFIG_RUST
1292	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh -v
1293	$(Q)$(MAKE) $(build)=rust
1294endif
1295
1296PHONY += remove-stale-files
1297remove-stale-files:
1298	$(Q)$(srctree)/scripts/remove-stale-files
1299
1300# Support for using generic headers in asm-generic
1301asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1302
1303PHONY += asm-generic uapi-asm-generic
1304asm-generic: uapi-asm-generic
1305	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1306	generic=include/asm-generic
1307uapi-asm-generic:
1308	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1309	generic=include/uapi/asm-generic
1310
1311# Generate some files
1312# ---------------------------------------------------------------------------
1313
1314# KERNELRELEASE can change from a few different places, meaning version.h
1315# needs to be updated, so this check is forced on all builds
1316
1317uts_len := 64
1318define filechk_utsrelease.h
1319	if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1320	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1321	  exit 1;                                                         \
1322	fi;                                                               \
1323	echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1324endef
1325
1326define filechk_version.h
1327	if [ $(SUBLEVEL) -gt 255 ]; then                                 \
1328		echo \#define LINUX_VERSION_CODE $(shell                 \
1329		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1330	else                                                             \
1331		echo \#define LINUX_VERSION_CODE $(shell                 \
1332		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1333	fi;                                                              \
1334	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
1335	((c) > 255 ? 255 : (c)))';                                       \
1336	echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
1337	echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
1338	echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1339endef
1340
1341$(version_h): PATCHLEVEL := $(or $(PATCHLEVEL), 0)
1342$(version_h): SUBLEVEL := $(or $(SUBLEVEL), 0)
1343$(version_h): FORCE
1344	$(call filechk,version.h)
1345
1346include/generated/utsrelease.h: include/config/kernel.release FORCE
1347	$(call filechk,utsrelease.h)
1348
1349filechk_compile.h = $(srctree)/scripts/mkcompile_h \
1350	"$(UTS_MACHINE)" "$(CONFIG_CC_VERSION_TEXT)" "$(LD)"
1351
1352include/generated/compile.h: FORCE
1353	$(call filechk,compile.h)
1354
1355PHONY += headerdep
1356headerdep:
1357	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1358	$(srctree)/scripts/headerdep.pl -I$(srctree)/include
1359
1360# ---------------------------------------------------------------------------
1361# Kernel headers
1362
1363#Default location for installed headers
1364export INSTALL_HDR_PATH = $(objtree)/usr
1365
1366quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1367      cmd_headers_install = \
1368	mkdir -p $(INSTALL_HDR_PATH); \
1369	rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1370	usr/include $(INSTALL_HDR_PATH)
1371
1372PHONY += headers_install
1373headers_install: headers
1374	$(call cmd,headers_install)
1375
1376PHONY += archheaders archscripts
1377
1378hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1379
1380PHONY += headers
1381headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1382	$(if $(filter um, $(SRCARCH)), $(error Headers not exportable for UML))
1383	$(Q)$(MAKE) $(hdr-inst)=include/uapi
1384	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1385
1386ifdef CONFIG_HEADERS_INSTALL
1387prepare: headers
1388endif
1389
1390PHONY += scripts_unifdef
1391scripts_unifdef: scripts_basic
1392	$(Q)$(MAKE) $(build)=scripts scripts/unifdef
1393
1394# ---------------------------------------------------------------------------
1395# Install
1396
1397# Many distributions have the custom install script, /sbin/installkernel.
1398# If DKMS is installed, 'make install' will eventually recurse back
1399# to this Makefile to build and install external modules.
1400# Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
1401
1402quiet_cmd_install = INSTALL $(INSTALL_PATH)
1403      cmd_install = unset sub_make_done; $(srctree)/scripts/install.sh
1404
1405# ---------------------------------------------------------------------------
1406# Tools
1407
1408ifdef CONFIG_OBJTOOL
1409prepare: tools/objtool
1410endif
1411
1412ifdef CONFIG_BPF
1413ifdef CONFIG_DEBUG_INFO_BTF
1414prepare: tools/bpf/resolve_btfids
1415endif
1416endif
1417
1418PHONY += resolve_btfids_clean
1419
1420resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1421
1422# tools/bpf/resolve_btfids directory might not exist
1423# in output directory, skip its clean in that case
1424resolve_btfids_clean:
1425ifneq ($(wildcard $(resolve_btfids_O)),)
1426	$(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1427endif
1428
1429# Clear a bunch of variables before executing the submake
1430ifeq ($(quiet),silent_)
1431tools_silent=s
1432endif
1433
1434tools/: FORCE
1435	$(Q)mkdir -p $(objtree)/tools
1436	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1437
1438tools/%: FORCE
1439	$(Q)mkdir -p $(objtree)/tools
1440	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1441
1442# ---------------------------------------------------------------------------
1443# Kernel selftest
1444
1445PHONY += kselftest
1446kselftest: headers
1447	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1448
1449kselftest-%: headers FORCE
1450	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1451
1452PHONY += kselftest-merge
1453kselftest-merge:
1454	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1455	$(Q)find $(srctree)/tools/testing/selftests -name config | \
1456		xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1457	$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1458
1459# ---------------------------------------------------------------------------
1460# Devicetree files
1461
1462ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1463dtstree := arch/$(SRCARCH)/boot/dts
1464endif
1465
1466ifneq ($(dtstree),)
1467
1468%.dtb: dtbs_prepare
1469	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1470
1471%.dtbo: dtbs_prepare
1472	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1473
1474PHONY += dtbs dtbs_prepare dtbs_install dtbs_check
1475dtbs: dtbs_prepare
1476	$(Q)$(MAKE) $(build)=$(dtstree)
1477
1478# include/config/kernel.release is actually needed when installing DTBs because
1479# INSTALL_DTBS_PATH contains $(KERNELRELEASE). However, we do not want to make
1480# dtbs_install depend on it as dtbs_install may run as root.
1481dtbs_prepare: include/config/kernel.release scripts_dtc
1482
1483ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1484export CHECK_DTBS=y
1485endif
1486
1487ifneq ($(CHECK_DTBS),)
1488dtbs_prepare: dt_binding_check
1489endif
1490
1491dtbs_check: dtbs
1492
1493dtbs_install:
1494	$(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1495
1496ifdef CONFIG_OF_EARLY_FLATTREE
1497all: dtbs
1498endif
1499
1500endif
1501
1502PHONY += scripts_dtc
1503scripts_dtc: scripts_basic
1504	$(Q)$(MAKE) $(build)=scripts/dtc
1505
1506ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1507export CHECK_DT_BINDING=y
1508endif
1509
1510PHONY += dt_binding_check
1511dt_binding_check: scripts_dtc
1512	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1513
1514PHONY += dt_compatible_check
1515dt_compatible_check: dt_binding_check
1516	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1517
1518# ---------------------------------------------------------------------------
1519# Modules
1520
1521ifdef CONFIG_MODULES
1522
1523# By default, build modules as well
1524
1525all: modules
1526
1527# When we're building modules with modversions, we need to consider
1528# the built-in objects during the descend as well, in order to
1529# make sure the checksums are up to date before we record them.
1530ifdef CONFIG_MODVERSIONS
1531  KBUILD_BUILTIN := 1
1532endif
1533
1534# Build modules
1535#
1536
1537# *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFO_BTF_MODULES
1538# is an exception.
1539ifdef CONFIG_DEBUG_INFO_BTF_MODULES
1540KBUILD_BUILTIN := 1
1541modules: vmlinux
1542endif
1543
1544modules: modules_prepare
1545
1546# Target to prepare building external modules
1547modules_prepare: prepare
1548	$(Q)$(MAKE) $(build)=scripts scripts/module.lds
1549
1550export modules_sign_only :=
1551
1552ifeq ($(CONFIG_MODULE_SIG),y)
1553PHONY += modules_sign
1554modules_sign: modules_install
1555	@:
1556
1557# modules_sign is a subset of modules_install.
1558# 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1559ifeq ($(filter modules_install,$(MAKECMDGOALS)),)
1560modules_sign_only := y
1561endif
1562endif
1563
1564endif # CONFIG_MODULES
1565
1566modinst_pre :=
1567ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
1568modinst_pre := __modinst_pre
1569endif
1570
1571modules_install: $(modinst_pre)
1572PHONY += __modinst_pre
1573__modinst_pre:
1574	@rm -rf $(MODLIB)/kernel
1575	@rm -f $(MODLIB)/source
1576	@mkdir -p $(MODLIB)
1577ifdef CONFIG_MODULES
1578	@ln -s $(abspath $(srctree)) $(MODLIB)/source
1579	@if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
1580		rm -f $(MODLIB)/build ; \
1581		ln -s $(CURDIR) $(MODLIB)/build ; \
1582	fi
1583	@sed 's:^\(.*\)\.o$$:kernel/\1.ko:' modules.order > $(MODLIB)/modules.order
1584endif
1585	@cp -f modules.builtin $(MODLIB)/
1586	@cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
1587
1588###
1589# Cleaning is done on three levels.
1590# make clean     Delete most generated files
1591#                Leave enough to build external modules
1592# make mrproper  Delete the current configuration, and all generated files
1593# make distclean Remove editor backup files, patch leftover files and the like
1594
1595# Directories & files removed with 'make clean'
1596CLEAN_FILES += include/ksym vmlinux.symvers modules-only.symvers \
1597	       modules.builtin modules.builtin.modinfo modules.nsdeps \
1598	       compile_commands.json .thinlto-cache rust/test rust/doc \
1599	       rust-project.json .vmlinux.objs .vmlinux.export.c
1600
1601# Directories & files removed with 'make mrproper'
1602MRPROPER_FILES += include/config include/generated          \
1603		  arch/$(SRCARCH)/include/generated .objdiff \
1604		  debian snap tar-install \
1605		  .config .config.old .version \
1606		  Module.symvers \
1607		  certs/signing_key.pem \
1608		  certs/x509.genkey \
1609		  vmlinux-gdb.py \
1610		  *.spec rpmbuild \
1611		  rust/libmacros.so
1612
1613# clean - Delete most, but leave enough to build external modules
1614#
1615clean: rm-files := $(CLEAN_FILES)
1616
1617PHONY += archclean vmlinuxclean
1618
1619vmlinuxclean:
1620	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1621	$(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1622
1623clean: archclean vmlinuxclean resolve_btfids_clean
1624
1625# mrproper - Delete all generated files, including .config
1626#
1627mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1628mrproper-dirs      := $(addprefix _mrproper_,scripts)
1629
1630PHONY += $(mrproper-dirs) mrproper
1631$(mrproper-dirs):
1632	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1633
1634mrproper: clean $(mrproper-dirs)
1635	$(call cmd,rmfiles)
1636	@find . $(RCS_FIND_IGNORE) \
1637		\( -name '*.rmeta' \) \
1638		-type f -print | xargs rm -f
1639
1640# distclean
1641#
1642PHONY += distclean
1643
1644distclean: mrproper
1645	@find . $(RCS_FIND_IGNORE) \
1646		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1647		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
1648		-o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1649		-o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1650		-type f -print | xargs rm -f
1651
1652
1653# Packaging of the kernel to various formats
1654# ---------------------------------------------------------------------------
1655
1656%src-pkg: FORCE
1657	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1658%pkg: include/config/kernel.release FORCE
1659	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1660
1661# Brief documentation of the typical targets used
1662# ---------------------------------------------------------------------------
1663
1664boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1665boards := $(sort $(notdir $(boards)))
1666board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1667board-dirs := $(sort $(notdir $(board-dirs:/=)))
1668
1669PHONY += help
1670help:
1671	@echo  'Cleaning targets:'
1672	@echo  '  clean		  - Remove most generated files but keep the config and'
1673	@echo  '                    enough build support to build external modules'
1674	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
1675	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
1676	@echo  ''
1677	@echo  'Configuration targets:'
1678	@$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1679	@echo  ''
1680	@echo  'Other generic targets:'
1681	@echo  '  all		  - Build all targets marked with [*]'
1682	@echo  '* vmlinux	  - Build the bare kernel'
1683	@echo  '* modules	  - Build all modules'
1684	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1685	@echo  '  dir/            - Build all files in dir and below'
1686	@echo  '  dir/file.[ois]  - Build specified target only'
1687	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1688	@echo  '                    (requires compiler support for LLVM assembly generation)'
1689	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1690	@echo  '                    (requires a recent binutils and recent build (System.map))'
1691	@echo  '  dir/file.ko     - Build module including final link'
1692	@echo  '  modules_prepare - Set up for building external modules'
1693	@echo  '  tags/TAGS	  - Generate tags file for editors'
1694	@echo  '  cscope	  - Generate cscope index'
1695	@echo  '  gtags           - Generate GNU GLOBAL index'
1696	@echo  '  kernelrelease	  - Output the release version string (use with make -s)'
1697	@echo  '  kernelversion	  - Output the version stored in Makefile (use with make -s)'
1698	@echo  '  image_name	  - Output the image name (use with make -s)'
1699	@echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1700	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1701	 echo  ''
1702	@echo  'Static analysers:'
1703	@echo  '  checkstack      - Generate a list of stack hogs'
1704	@echo  '  versioncheck    - Sanity check on version.h usage'
1705	@echo  '  includecheck    - Check for duplicate included header files'
1706	@echo  '  export_report   - List the usages of all exported symbols'
1707	@echo  '  headerdep       - Detect inclusion cycles in headers'
1708	@echo  '  coccicheck      - Check with Coccinelle'
1709	@echo  '  clang-analyzer  - Check with clang static analyzer'
1710	@echo  '  clang-tidy      - Check with clang-tidy'
1711	@echo  ''
1712	@echo  'Tools:'
1713	@echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1714	@echo  ''
1715	@echo  'Kernel selftest:'
1716	@echo  '  kselftest         - Build and run kernel selftest'
1717	@echo  '                      Build, install, and boot kernel before'
1718	@echo  '                      running kselftest on it'
1719	@echo  '                      Run as root for full coverage'
1720	@echo  '  kselftest-all     - Build kernel selftest'
1721	@echo  '  kselftest-install - Build and install kernel selftest'
1722	@echo  '  kselftest-clean   - Remove all generated kselftest files'
1723	@echo  '  kselftest-merge   - Merge all the config dependencies of'
1724	@echo  '		      kselftest to existing .config.'
1725	@echo  ''
1726	@echo  'Rust targets:'
1727	@echo  '  rustavailable   - Checks whether the Rust toolchain is'
1728	@echo  '		    available and, if not, explains why.'
1729	@echo  '  rustfmt	  - Reformat all the Rust code in the kernel'
1730	@echo  '  rustfmtcheck	  - Checks if all the Rust code in the kernel'
1731	@echo  '		    is formatted, printing a diff otherwise.'
1732	@echo  '  rustdoc	  - Generate Rust documentation'
1733	@echo  '		    (requires kernel .config)'
1734	@echo  '  rusttest        - Runs the Rust tests'
1735	@echo  '                    (requires kernel .config; downloads external repos)'
1736	@echo  '  rust-analyzer	  - Generate rust-project.json rust-analyzer support file'
1737	@echo  '		    (requires kernel .config)'
1738	@echo  '  dir/file.[os]   - Build specified target only'
1739	@echo  '  dir/file.rsi    - Build macro expanded source, similar to C preprocessing.'
1740	@echo  '                    Run with RUSTFMT=n to skip reformatting if needed.'
1741	@echo  '                    The output is not intended to be compilable.'
1742	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1743	@echo  ''
1744	@$(if $(dtstree), \
1745		echo 'Devicetree:'; \
1746		echo '* dtbs             - Build device tree blobs for enabled boards'; \
1747		echo '  dtbs_install     - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1748		echo '  dt_binding_check - Validate device tree binding documents'; \
1749		echo '  dtbs_check       - Validate device tree source files';\
1750		echo '')
1751
1752	@echo 'Userspace tools targets:'
1753	@echo '  use "make tools/help"'
1754	@echo '  or  "cd tools; make help"'
1755	@echo  ''
1756	@echo  'Kernel packaging:'
1757	@$(MAKE) -f $(srctree)/scripts/Makefile.package help
1758	@echo  ''
1759	@echo  'Documentation targets:'
1760	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1761	@echo  ''
1762	@echo  'Architecture specific targets ($(SRCARCH)):'
1763	@$(or $(archhelp),\
1764		echo '  No architecture specific help defined for $(SRCARCH)')
1765	@echo  ''
1766	@$(if $(boards), \
1767		$(foreach b, $(boards), \
1768		printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1769		echo '')
1770	@$(if $(board-dirs), \
1771		$(foreach b, $(board-dirs), \
1772		printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1773		printf "  %-16s - Show all of the above\\n" help-boards; \
1774		echo '')
1775
1776	@echo  '  make V=n   [targets] 1: verbose build'
1777	@echo  '                       2: give reason for rebuild of target'
1778	@echo  '                       V=1 and V=2 can be combined with V=12'
1779	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1780	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1781	@echo  '                       (sparse by default)'
1782	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1783	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1784	@echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
1785	@echo  '		1: warnings which may be relevant and do not occur too often'
1786	@echo  '		2: warnings which occur quite often but may still be relevant'
1787	@echo  '		3: more obscure warnings, can most likely be ignored'
1788	@echo  '		e: warnings are being treated as errors'
1789	@echo  '		Multiple levels can be combined with W=12 or W=123'
1790	@$(if $(dtstree), \
1791		echo '  make CHECK_DTBS=1 [targets] Check all generated dtb files against schema'; \
1792		echo '         This can be applied both to "dtbs" and to individual "foo.dtb" targets' ; \
1793		)
1794	@echo  ''
1795	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
1796	@echo  'For further info see the ./README file'
1797
1798
1799help-board-dirs := $(addprefix help-,$(board-dirs))
1800
1801help-boards: $(help-board-dirs)
1802
1803boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1804
1805$(help-board-dirs): help-%:
1806	@echo  'Architecture specific targets ($(SRCARCH) $*):'
1807	@$(if $(boards-per-dir), \
1808		$(foreach b, $(boards-per-dir), \
1809		printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1810		echo '')
1811
1812
1813# Documentation targets
1814# ---------------------------------------------------------------------------
1815DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1816	       linkcheckdocs dochelp refcheckdocs texinfodocs infodocs
1817PHONY += $(DOC_TARGETS)
1818$(DOC_TARGETS):
1819	$(Q)$(MAKE) $(build)=Documentation $@
1820
1821
1822# Rust targets
1823# ---------------------------------------------------------------------------
1824
1825# "Is Rust available?" target
1826PHONY += rustavailable
1827rustavailable:
1828	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh -v && echo "Rust is available!"
1829
1830# Documentation target
1831#
1832# Using the singular to avoid running afoul of `no-dot-config-targets`.
1833PHONY += rustdoc
1834rustdoc: prepare
1835	$(Q)$(MAKE) $(build)=rust $@
1836
1837# Testing target
1838PHONY += rusttest
1839rusttest: prepare
1840	$(Q)$(MAKE) $(build)=rust $@
1841
1842# Formatting targets
1843PHONY += rustfmt rustfmtcheck
1844
1845# We skip `rust/alloc` since we want to minimize the diff w.r.t. upstream.
1846#
1847# We match using absolute paths since `find` does not resolve them
1848# when matching, which is a problem when e.g. `srctree` is `..`.
1849# We `grep` afterwards in order to remove the directory entry itself.
1850rustfmt:
1851	$(Q)find $(abs_srctree) -type f -name '*.rs' \
1852		-o -path $(abs_srctree)/rust/alloc -prune \
1853		-o -path $(abs_objtree)/rust/test -prune \
1854		| grep -Fv $(abs_srctree)/rust/alloc \
1855		| grep -Fv $(abs_objtree)/rust/test \
1856		| grep -Fv generated \
1857		| xargs $(RUSTFMT) $(rustfmt_flags)
1858
1859rustfmtcheck: rustfmt_flags = --check
1860rustfmtcheck: rustfmt
1861
1862# IDE support targets
1863PHONY += rust-analyzer
1864rust-analyzer:
1865	$(Q)$(MAKE) $(build)=rust $@
1866
1867# Misc
1868# ---------------------------------------------------------------------------
1869
1870PHONY += misc-check
1871misc-check:
1872	$(Q)$(srctree)/scripts/misc-check
1873
1874all: misc-check
1875
1876PHONY += scripts_gdb
1877scripts_gdb: prepare0
1878	$(Q)$(MAKE) $(build)=scripts/gdb
1879	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1880
1881ifdef CONFIG_GDB_SCRIPTS
1882all: scripts_gdb
1883endif
1884
1885else # KBUILD_EXTMOD
1886
1887filechk_kernel.release = echo $(KERNELRELEASE)
1888
1889###
1890# External module support.
1891# When building external modules the kernel used as basis is considered
1892# read-only, and no consistency checks are made and the make
1893# system is not used on the basis kernel. If updates are required
1894# in the basis kernel ordinary make commands (without M=...) must be used.
1895
1896# We are always building only modules.
1897KBUILD_BUILTIN :=
1898KBUILD_MODULES := 1
1899
1900build-dir := $(KBUILD_EXTMOD)
1901
1902compile_commands.json: $(extmod_prefix)compile_commands.json
1903PHONY += compile_commands.json
1904
1905clean-dirs := $(KBUILD_EXTMOD)
1906clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1907	$(KBUILD_EXTMOD)/compile_commands.json $(KBUILD_EXTMOD)/.thinlto-cache
1908
1909PHONY += prepare
1910# now expand this into a simple variable to reduce the cost of shell evaluations
1911prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT)
1912prepare:
1913	@if [ "$(CC_VERSION_TEXT)" != "$(CONFIG_CC_VERSION_TEXT)" ]; then \
1914		echo >&2 "warning: the compiler differs from the one used to build the kernel"; \
1915		echo >&2 "  The kernel was built by: $(CONFIG_CC_VERSION_TEXT)"; \
1916		echo >&2 "  You are using:           $(CC_VERSION_TEXT)"; \
1917	fi
1918
1919PHONY += help
1920help:
1921	@echo  '  Building external modules.'
1922	@echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1923	@echo  ''
1924	@echo  '  modules         - default target, build the module(s)'
1925	@echo  '  modules_install - install the module'
1926	@echo  '  clean           - remove generated files in module directory only'
1927	@echo  ''
1928
1929__external_modules_error:
1930	@echo >&2 '***'
1931	@echo >&2 '*** The present kernel disabled CONFIG_MODULES.'
1932	@echo >&2 '*** You cannot build or install external modules.'
1933	@echo >&2 '***'
1934	@false
1935
1936endif # KBUILD_EXTMOD
1937
1938# ---------------------------------------------------------------------------
1939# Modules
1940
1941PHONY += modules modules_install modules_prepare
1942
1943ifdef CONFIG_MODULES
1944
1945$(MODORDER): $(build-dir)
1946	@:
1947
1948# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
1949# This is solely useful to speed up test compiles.
1950modules: modpost
1951ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1952	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1953endif
1954
1955PHONY += modules_check
1956modules_check: $(MODORDER)
1957	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1958
1959quiet_cmd_depmod = DEPMOD  $(MODLIB)
1960      cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1961                   $(KERNELRELEASE)
1962
1963modules_install:
1964	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1965	$(call cmd,depmod)
1966
1967else # CONFIG_MODULES
1968
1969# Modules not configured
1970# ---------------------------------------------------------------------------
1971
1972PHONY += __external_modules_error
1973
1974modules modules_install: __external_modules_error
1975	@:
1976
1977KBUILD_MODULES :=
1978
1979endif # CONFIG_MODULES
1980
1981PHONY += modpost
1982modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \
1983	 $(if $(KBUILD_MODULES), modules_check)
1984	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1985
1986# Single targets
1987# ---------------------------------------------------------------------------
1988# To build individual files in subdirectories, you can do like this:
1989#
1990#   make foo/bar/baz.s
1991#
1992# The supported suffixes for single-target are listed in 'single-targets'
1993#
1994# To build only under specific subdirectories, you can do like this:
1995#
1996#   make foo/bar/baz/
1997
1998ifdef single-build
1999
2000# .ko is special because modpost is needed
2001single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
2002single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \
2003		$(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko)))
2004
2005$(single-ko): single_modules
2006	@:
2007$(single-no-ko): $(build-dir)
2008	@:
2009
2010# Remove MODORDER when done because it is not the real one.
2011PHONY += single_modules
2012single_modules: $(single-no-ko) modules_prepare
2013	$(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$(m:%.ko=%.o);) } > $(MODORDER)
2014	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
2015ifneq ($(KBUILD_MODPOST_NOFINAL),1)
2016	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
2017endif
2018	$(Q)rm -f $(MODORDER)
2019
2020single-goals := $(addprefix $(build-dir)/, $(single-no-ko))
2021
2022KBUILD_MODULES := 1
2023
2024endif
2025
2026# Preset locale variables to speed up the build process. Limit locale
2027# tweaks to this spot to avoid wrong language settings when running
2028# make menuconfig etc.
2029# Error messages still appears in the original language
2030PHONY += $(build-dir)
2031$(build-dir): prepare
2032	$(Q)$(MAKE) $(build)=$@ need-builtin=1 need-modorder=1 $(single-goals)
2033
2034clean-dirs := $(addprefix _clean_, $(clean-dirs))
2035PHONY += $(clean-dirs) clean
2036$(clean-dirs):
2037	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
2038
2039clean: $(clean-dirs)
2040	$(call cmd,rmfiles)
2041	@find $(or $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
2042		\( -name '*.[aios]' -o -name '*.rsi' -o -name '*.ko' -o -name '.*.cmd' \
2043		-o -name '*.ko.*' \
2044		-o -name '*.dtb' -o -name '*.dtbo' \
2045		-o -name '*.dtb.S' -o -name '*.dtbo.S' \
2046		-o -name '*.dt.yaml' \
2047		-o -name '*.dwo' -o -name '*.lst' \
2048		-o -name '*.su' -o -name '*.mod' \
2049		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
2050		-o -name '*.lex.c' -o -name '*.tab.[ch]' \
2051		-o -name '*.asn1.[ch]' \
2052		-o -name '*.symtypes' -o -name 'modules.order' \
2053		-o -name '*.c.[012]*.*' \
2054		-o -name '*.ll' \
2055		-o -name '*.gcno' \
2056		-o -name '*.*.symversions' \) -type f -print \
2057		-o -name '.tmp_*' -print \
2058		| xargs rm -rf
2059
2060# Generate tags for editors
2061# ---------------------------------------------------------------------------
2062quiet_cmd_tags = GEN     $@
2063      cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
2064
2065tags TAGS cscope gtags: FORCE
2066	$(call cmd,tags)
2067
2068# Script to generate missing namespace dependencies
2069# ---------------------------------------------------------------------------
2070
2071PHONY += nsdeps
2072nsdeps: export KBUILD_NSDEPS=1
2073nsdeps: modules
2074	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
2075
2076# Clang Tooling
2077# ---------------------------------------------------------------------------
2078
2079quiet_cmd_gen_compile_commands = GEN     $@
2080      cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
2081
2082$(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
2083	$(if $(KBUILD_EXTMOD),, vmlinux.a $(KBUILD_VMLINUX_LIBS)) \
2084	$(if $(CONFIG_MODULES), $(MODORDER)) FORCE
2085	$(call if_changed,gen_compile_commands)
2086
2087targets += $(extmod_prefix)compile_commands.json
2088
2089PHONY += clang-tidy clang-analyzer
2090
2091ifdef CONFIG_CC_IS_CLANG
2092quiet_cmd_clang_tools = CHECK   $<
2093      cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
2094
2095clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
2096	$(call cmd,clang_tools)
2097else
2098clang-tidy clang-analyzer:
2099	@echo "$@ requires CC=clang" >&2
2100	@false
2101endif
2102
2103# Scripts to check various things for consistency
2104# ---------------------------------------------------------------------------
2105
2106PHONY += includecheck versioncheck coccicheck export_report
2107
2108includecheck:
2109	find $(srctree)/* $(RCS_FIND_IGNORE) \
2110		-name '*.[hcS]' -type f -print | sort \
2111		| xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
2112
2113versioncheck:
2114	find $(srctree)/* $(RCS_FIND_IGNORE) \
2115		-name '*.[hcS]' -type f -print | sort \
2116		| xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
2117
2118coccicheck:
2119	$(Q)$(BASH) $(srctree)/scripts/$@
2120
2121export_report:
2122	$(PERL) $(srctree)/scripts/export_report.pl
2123
2124PHONY += checkstack kernelrelease kernelversion image_name
2125
2126# UML needs a little special treatment here.  It wants to use the host
2127# toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
2128# else wants $(ARCH), including people doing cross-builds, which means
2129# that $(SUBARCH) doesn't work here.
2130ifeq ($(ARCH), um)
2131CHECKSTACK_ARCH := $(SUBARCH)
2132else
2133CHECKSTACK_ARCH := $(ARCH)
2134endif
2135checkstack:
2136	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
2137	$(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
2138
2139kernelrelease:
2140	@$(filechk_kernel.release)
2141
2142kernelversion:
2143	@echo $(KERNELVERSION)
2144
2145image_name:
2146	@echo $(KBUILD_IMAGE)
2147
2148quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
2149      cmd_rmfiles = rm -rf $(rm-files)
2150
2151# read saved command lines for existing targets
2152existing-targets := $(wildcard $(sort $(targets)))
2153
2154-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
2155
2156endif # config-build
2157endif # mixed-build
2158endif # need-sub-make
2159
2160PHONY += FORCE
2161FORCE:
2162
2163# Declare the contents of the PHONY variable as phony.  We keep that
2164# information in a variable so we can use it in if_changed and friends.
2165.PHONY: $(PHONY)
2166