Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1# SPDX-License-Identifier: GPL-2.0
2VERSION = 6
3PATCHLEVEL = 14
4SUBLEVEL = 0
5EXTRAVERSION =
6NAME = Baby Opossum Posse
7
8# *DOCUMENTATION*
9# To see a list of typical targets execute "make help"
10# More info can be located in ./README
11# Comments in this file are targeted only to the developer, do not
12# expect to learn how to build the kernel reading this file.
13
14ifeq ($(filter output-sync,$(.FEATURES)),)
15$(error GNU Make >= 4.0 is required. Your Make version is $(MAKE_VERSION))
16endif
17
18$(if $(filter __%, $(MAKECMDGOALS)), \
19 $(error targets prefixed with '__' are only for internal use))
20
21# That's our default target when none is given on the command line
22PHONY := __all
23__all:
24
25# We are using a recursive build, so we need to do a little thinking
26# to get the ordering right.
27#
28# Most importantly: sub-Makefiles should only ever modify files in
29# their own directory. If in some directory we have a dependency on
30# a file in another dir (which doesn't happen often, but it's often
31# unavoidable when linking the built-in.a targets which finally
32# turn into vmlinux), we will call a sub make in that other dir, and
33# after that we are sure that everything which is in that other dir
34# is now up to date.
35#
36# The only cases where we need to modify files which have global
37# effects are thus separated out and done before the recursive
38# descending is started. They are now explicitly listed as the
39# prepare rule.
40
41this-makefile := $(lastword $(MAKEFILE_LIST))
42abs_srctree := $(realpath $(dir $(this-makefile)))
43abs_output := $(CURDIR)
44
45ifneq ($(sub_make_done),1)
46
47# Do not use make's built-in rules and variables
48# (this increases performance and avoids hard-to-debug behaviour)
49MAKEFLAGS += -rR
50
51# Avoid funny character set dependencies
52unexport LC_ALL
53LC_COLLATE=C
54LC_NUMERIC=C
55export LC_COLLATE LC_NUMERIC
56
57# Avoid interference with shell env settings
58unexport GREP_OPTIONS
59
60# Beautify output
61# ---------------------------------------------------------------------------
62#
63# Most of build commands in Kbuild start with "cmd_". You can optionally define
64# "quiet_cmd_*". If defined, the short log is printed. Otherwise, no log from
65# that command is printed by default.
66#
67# e.g.)
68# quiet_cmd_depmod = DEPMOD $(MODLIB)
69# cmd_depmod = $(srctree)/scripts/depmod.sh $(DEPMOD) $(KERNELRELEASE)
70#
71# A simple variant is to prefix commands with $(Q) - that's useful
72# for commands that shall be hidden in non-verbose mode.
73#
74# $(Q)$(MAKE) $(build)=scripts/basic
75#
76# If KBUILD_VERBOSE contains 1, the whole command is echoed.
77# If KBUILD_VERBOSE contains 2, the reason for rebuilding is printed.
78#
79# To put more focus on warnings, be less verbose as default
80# Use 'make V=1' to see the full commands
81
82ifeq ("$(origin V)", "command line")
83 KBUILD_VERBOSE = $(V)
84endif
85
86quiet = quiet_
87Q = @
88
89ifneq ($(findstring 1, $(KBUILD_VERBOSE)),)
90 quiet =
91 Q =
92endif
93
94# If the user is running make -s (silent mode), suppress echoing of
95# commands
96ifneq ($(findstring s,$(firstword -$(MAKEFLAGS))),)
97quiet=silent_
98override KBUILD_VERBOSE :=
99endif
100
101export quiet Q KBUILD_VERBOSE
102
103# Call a source code checker (by default, "sparse") as part of the
104# C compilation.
105#
106# Use 'make C=1' to enable checking of only re-compiled files.
107# Use 'make C=2' to enable checking of *all* source files, regardless
108# of whether they are re-compiled or not.
109#
110# See the file "Documentation/dev-tools/sparse.rst" for more details,
111# including where to get the "sparse" utility.
112
113ifeq ("$(origin C)", "command line")
114 KBUILD_CHECKSRC = $(C)
115endif
116ifndef KBUILD_CHECKSRC
117 KBUILD_CHECKSRC = 0
118endif
119
120export KBUILD_CHECKSRC
121
122# Enable "clippy" (a linter) as part of the Rust compilation.
123#
124# Use 'make CLIPPY=1' to enable it.
125ifeq ("$(origin CLIPPY)", "command line")
126 KBUILD_CLIPPY := $(CLIPPY)
127endif
128
129export KBUILD_CLIPPY
130
131# Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
132# directory of external module to build. Setting M= takes precedence.
133ifeq ("$(origin M)", "command line")
134 KBUILD_EXTMOD := $(M)
135endif
136
137ifeq ("$(origin MO)", "command line")
138 KBUILD_EXTMOD_OUTPUT := $(MO)
139endif
140
141$(if $(word 2, $(KBUILD_EXTMOD)), \
142 $(error building multiple external modules is not supported))
143
144$(foreach x, % :, $(if $(findstring $x, $(KBUILD_EXTMOD)), \
145 $(error module directory path cannot contain '$x')))
146
147# Remove trailing slashes
148ifneq ($(filter %/, $(KBUILD_EXTMOD)),)
149KBUILD_EXTMOD := $(shell dirname $(KBUILD_EXTMOD).)
150endif
151
152export KBUILD_EXTMOD
153
154# backward compatibility
155KBUILD_EXTRA_WARN ?= $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)
156
157ifeq ("$(origin W)", "command line")
158 KBUILD_EXTRA_WARN := $(W)
159endif
160
161export KBUILD_EXTRA_WARN
162
163# Kbuild will save output files in the current working directory.
164# This does not need to match to the root of the kernel source tree.
165#
166# For example, you can do this:
167#
168# cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
169#
170# If you want to save output files in a different location, there are
171# two syntaxes to specify it.
172#
173# 1) O=
174# Use "make O=dir/to/store/output/files/"
175#
176# 2) Set KBUILD_OUTPUT
177# Set the environment variable KBUILD_OUTPUT to point to the output directory.
178# export KBUILD_OUTPUT=dir/to/store/output/files/; make
179#
180# The O= assignment takes precedence over the KBUILD_OUTPUT environment
181# variable.
182
183ifeq ("$(origin O)", "command line")
184 KBUILD_OUTPUT := $(O)
185endif
186
187ifdef KBUILD_EXTMOD
188 ifdef KBUILD_OUTPUT
189 objtree := $(realpath $(KBUILD_OUTPUT))
190 $(if $(objtree),,$(error specified kernel directory "$(KBUILD_OUTPUT)" does not exist))
191 else
192 objtree := $(abs_srctree)
193 endif
194 # If Make is invoked from the kernel directory (either kernel
195 # source directory or kernel build directory), external modules
196 # are built in $(KBUILD_EXTMOD) for backward compatibility,
197 # otherwise, built in the current directory.
198 output := $(or $(KBUILD_EXTMOD_OUTPUT),$(if $(filter $(CURDIR),$(objtree) $(abs_srctree)),$(KBUILD_EXTMOD)))
199 # KBUILD_EXTMOD might be a relative path. Remember its absolute path before
200 # Make changes the working directory.
201 srcroot := $(realpath $(KBUILD_EXTMOD))
202 $(if $(srcroot),,$(error specified external module directory "$(KBUILD_EXTMOD)" does not exist))
203else
204 objtree := .
205 output := $(KBUILD_OUTPUT)
206endif
207
208export objtree srcroot
209
210# Do we want to change the working directory?
211ifneq ($(output),)
212# $(realpath ...) gets empty if the path does not exist. Run 'mkdir -p' first.
213$(shell mkdir -p "$(output)")
214# $(realpath ...) resolves symlinks
215abs_output := $(realpath $(output))
216$(if $(abs_output),,$(error failed to create output directory "$(output)"))
217endif
218
219ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
220$(error source directory cannot contain spaces or colons)
221endif
222
223export sub_make_done := 1
224
225endif # sub_make_done
226
227ifeq ($(abs_output),$(CURDIR))
228# Suppress "Entering directory ..." if we are at the final work directory.
229no-print-directory := --no-print-directory
230else
231# Recursion to show "Entering directory ..."
232need-sub-make := 1
233endif
234
235ifeq ($(filter --no-print-directory, $(MAKEFLAGS)),)
236# If --no-print-directory is unset, recurse once again to set it.
237# You may end up recursing into __sub-make twice. This is needed due to the
238# behavior change in GNU Make 4.4.1.
239need-sub-make := 1
240endif
241
242ifeq ($(need-sub-make),1)
243
244PHONY += $(MAKECMDGOALS) __sub-make
245
246$(filter-out $(this-makefile), $(MAKECMDGOALS)) __all: __sub-make
247 @:
248
249# Invoke a second make in the output directory, passing relevant variables
250__sub-make:
251 $(Q)$(MAKE) $(no-print-directory) -C $(abs_output) \
252 -f $(abs_srctree)/Makefile $(MAKECMDGOALS)
253
254else # need-sub-make
255
256# We process the rest of the Makefile if this is the final invocation of make
257
258ifndef KBUILD_EXTMOD
259srcroot := $(abs_srctree)
260endif
261
262ifeq ($(srcroot),$(CURDIR))
263building_out_of_srctree :=
264else
265export building_out_of_srctree := 1
266endif
267
268ifdef KBUILD_ABS_SRCTREE
269 # Do nothing. Use the absolute path.
270else ifeq ($(srcroot),$(CURDIR))
271 # Building in the source.
272 srcroot := .
273else ifeq ($(srcroot)/,$(dir $(CURDIR)))
274 # Building in a subdirectory of the source.
275 srcroot := ..
276endif
277
278export srctree := $(if $(KBUILD_EXTMOD),$(abs_srctree),$(srcroot))
279
280ifdef building_out_of_srctree
281export VPATH := $(srcroot)
282else
283VPATH :=
284endif
285
286# To make sure we do not include .config for any of the *config targets
287# catch them early, and hand them over to scripts/kconfig/Makefile
288# It is allowed to specify more targets when calling make, including
289# mixing *config targets and build targets.
290# For example 'make oldconfig all'.
291# Detect when mixed targets is specified, and make a second invocation
292# of make so .config is not included in this case either (for *config).
293
294version_h := include/generated/uapi/linux/version.h
295
296clean-targets := %clean mrproper cleandocs
297no-dot-config-targets := $(clean-targets) \
298 cscope gtags TAGS tags help% %docs check% coccicheck \
299 $(version_h) headers headers_% archheaders archscripts \
300 %asm-generic kernelversion %src-pkg dt_binding_check \
301 outputmakefile rustavailable rustfmt rustfmtcheck
302no-sync-config-targets := $(no-dot-config-targets) %install modules_sign kernelrelease \
303 image_name
304single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.rsi %.s %/
305
306config-build :=
307mixed-build :=
308need-config := 1
309may-sync-config := 1
310single-build :=
311
312ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
313 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
314 need-config :=
315 endif
316endif
317
318ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
319 ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
320 may-sync-config :=
321 endif
322endif
323
324need-compiler := $(may-sync-config)
325
326ifneq ($(KBUILD_EXTMOD),)
327 may-sync-config :=
328endif
329
330ifeq ($(KBUILD_EXTMOD),)
331 ifneq ($(filter %config,$(MAKECMDGOALS)),)
332 config-build := 1
333 ifneq ($(words $(MAKECMDGOALS)),1)
334 mixed-build := 1
335 endif
336 endif
337endif
338
339# We cannot build single targets and the others at the same time
340ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
341 single-build := 1
342 ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
343 mixed-build := 1
344 endif
345endif
346
347# For "make -j clean all", "make -j mrproper defconfig all", etc.
348ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
349 ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
350 mixed-build := 1
351 endif
352endif
353
354# install and modules_install need also be processed one by one
355ifneq ($(filter install,$(MAKECMDGOALS)),)
356 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
357 mixed-build := 1
358 endif
359endif
360
361ifdef mixed-build
362# ===========================================================================
363# We're called with mixed targets (*config and build targets).
364# Handle them one by one.
365
366PHONY += $(MAKECMDGOALS) __build_one_by_one
367
368$(MAKECMDGOALS): __build_one_by_one
369 @:
370
371__build_one_by_one:
372 $(Q)set -e; \
373 for i in $(MAKECMDGOALS); do \
374 $(MAKE) -f $(srctree)/Makefile $$i; \
375 done
376
377else # !mixed-build
378
379include $(srctree)/scripts/Kbuild.include
380
381# Read KERNELRELEASE from include/config/kernel.release (if it exists)
382KERNELRELEASE = $(call read-file, $(objtree)/include/config/kernel.release)
383KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
384export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
385
386include $(srctree)/scripts/subarch.include
387
388# Cross compiling and selecting different set of gcc/bin-utils
389# ---------------------------------------------------------------------------
390#
391# When performing cross compilation for other architectures ARCH shall be set
392# to the target architecture. (See arch/* for the possibilities).
393# ARCH can be set during invocation of make:
394# make ARCH=arm64
395# Another way is to have ARCH set in the environment.
396# The default ARCH is the host where make is executed.
397
398# CROSS_COMPILE specify the prefix used for all executables used
399# during compilation. Only gcc and related bin-utils executables
400# are prefixed with $(CROSS_COMPILE).
401# CROSS_COMPILE can be set on the command line
402# make CROSS_COMPILE=aarch64-linux-gnu-
403# Alternatively CROSS_COMPILE can be set in the environment.
404# Default value for CROSS_COMPILE is not to prefix executables
405# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
406ARCH ?= $(SUBARCH)
407
408# Architecture as present in compile.h
409UTS_MACHINE := $(ARCH)
410SRCARCH := $(ARCH)
411
412# Additional ARCH settings for x86
413ifeq ($(ARCH),i386)
414 SRCARCH := x86
415endif
416ifeq ($(ARCH),x86_64)
417 SRCARCH := x86
418endif
419
420# Additional ARCH settings for sparc
421ifeq ($(ARCH),sparc32)
422 SRCARCH := sparc
423endif
424ifeq ($(ARCH),sparc64)
425 SRCARCH := sparc
426endif
427
428# Additional ARCH settings for parisc
429ifeq ($(ARCH),parisc64)
430 SRCARCH := parisc
431endif
432
433export cross_compiling :=
434ifneq ($(SRCARCH),$(SUBARCH))
435cross_compiling := 1
436endif
437
438KCONFIG_CONFIG ?= .config
439export KCONFIG_CONFIG
440
441# SHELL used by kbuild
442CONFIG_SHELL := sh
443
444HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
445HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
446HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
447
448ifneq ($(LLVM),)
449ifneq ($(filter %/,$(LLVM)),)
450LLVM_PREFIX := $(LLVM)
451else ifneq ($(filter -%,$(LLVM)),)
452LLVM_SUFFIX := $(LLVM)
453endif
454
455HOSTCC = $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
456HOSTCXX = $(LLVM_PREFIX)clang++$(LLVM_SUFFIX)
457else
458HOSTCC = gcc
459HOSTCXX = g++
460endif
461HOSTRUSTC = rustc
462HOSTPKG_CONFIG = pkg-config
463
464KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
465 -O2 -fomit-frame-pointer -std=gnu11
466KBUILD_USERCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(USERCFLAGS)
467KBUILD_USERLDFLAGS := $(USERLDFLAGS)
468
469# These flags apply to all Rust code in the tree, including the kernel and
470# host programs.
471export rust_common_flags := --edition=2021 \
472 -Zbinary_dep_depinfo=y \
473 -Astable_features \
474 -Dnon_ascii_idents \
475 -Dunsafe_op_in_unsafe_fn \
476 -Wmissing_docs \
477 -Wrust_2018_idioms \
478 -Wunreachable_pub \
479 -Wclippy::all \
480 -Wclippy::ignored_unit_patterns \
481 -Wclippy::mut_mut \
482 -Wclippy::needless_bitwise_bool \
483 -Wclippy::needless_continue \
484 -Aclippy::needless_lifetimes \
485 -Wclippy::no_mangle_with_rust_abi \
486 -Wclippy::undocumented_unsafe_blocks \
487 -Wclippy::unnecessary_safety_comment \
488 -Wclippy::unnecessary_safety_doc \
489 -Wrustdoc::missing_crate_level_docs \
490 -Wrustdoc::unescaped_backticks
491
492KBUILD_HOSTCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) \
493 $(HOSTCFLAGS) -I $(srctree)/scripts/include
494KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS) \
495 -I $(srctree)/scripts/include
496KBUILD_HOSTRUSTFLAGS := $(rust_common_flags) -O -Cstrip=debuginfo \
497 -Zallow-features= $(HOSTRUSTFLAGS)
498KBUILD_HOSTLDFLAGS := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
499KBUILD_HOSTLDLIBS := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
500KBUILD_PROCMACROLDFLAGS := $(or $(PROCMACROLDFLAGS),$(KBUILD_HOSTLDFLAGS))
501
502# Make variables (CC, etc...)
503CPP = $(CC) -E
504ifneq ($(LLVM),)
505CC = $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
506LD = $(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX)
507AR = $(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX)
508NM = $(LLVM_PREFIX)llvm-nm$(LLVM_SUFFIX)
509OBJCOPY = $(LLVM_PREFIX)llvm-objcopy$(LLVM_SUFFIX)
510OBJDUMP = $(LLVM_PREFIX)llvm-objdump$(LLVM_SUFFIX)
511READELF = $(LLVM_PREFIX)llvm-readelf$(LLVM_SUFFIX)
512STRIP = $(LLVM_PREFIX)llvm-strip$(LLVM_SUFFIX)
513else
514CC = $(CROSS_COMPILE)gcc
515LD = $(CROSS_COMPILE)ld
516AR = $(CROSS_COMPILE)ar
517NM = $(CROSS_COMPILE)nm
518OBJCOPY = $(CROSS_COMPILE)objcopy
519OBJDUMP = $(CROSS_COMPILE)objdump
520READELF = $(CROSS_COMPILE)readelf
521STRIP = $(CROSS_COMPILE)strip
522endif
523RUSTC = rustc
524RUSTDOC = rustdoc
525RUSTFMT = rustfmt
526CLIPPY_DRIVER = clippy-driver
527BINDGEN = bindgen
528PAHOLE = pahole
529RESOLVE_BTFIDS = $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
530LEX = flex
531YACC = bison
532AWK = awk
533INSTALLKERNEL := installkernel
534PERL = perl
535PYTHON3 = python3
536CHECK = sparse
537BASH = bash
538KGZIP = gzip
539KBZIP2 = bzip2
540KLZOP = lzop
541LZMA = lzma
542LZ4 = lz4
543XZ = xz
544ZSTD = zstd
545
546CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
547 -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
548NOSTDINC_FLAGS :=
549CFLAGS_MODULE =
550RUSTFLAGS_MODULE =
551AFLAGS_MODULE =
552LDFLAGS_MODULE =
553CFLAGS_KERNEL =
554RUSTFLAGS_KERNEL =
555AFLAGS_KERNEL =
556LDFLAGS_vmlinux =
557
558# Use USERINCLUDE when you must reference the UAPI directories only.
559USERINCLUDE := \
560 -I$(srctree)/arch/$(SRCARCH)/include/uapi \
561 -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
562 -I$(srctree)/include/uapi \
563 -I$(objtree)/include/generated/uapi \
564 -include $(srctree)/include/linux/compiler-version.h \
565 -include $(srctree)/include/linux/kconfig.h
566
567# Use LINUXINCLUDE when you must reference the include/ directory.
568# Needed to be compatible with the O= option
569LINUXINCLUDE := \
570 -I$(srctree)/arch/$(SRCARCH)/include \
571 -I$(objtree)/arch/$(SRCARCH)/include/generated \
572 -I$(srctree)/include \
573 -I$(objtree)/include \
574 $(USERINCLUDE)
575
576KBUILD_AFLAGS := -D__ASSEMBLY__ -fno-PIE
577
578KBUILD_CFLAGS :=
579KBUILD_CFLAGS += -std=gnu11
580KBUILD_CFLAGS += -fshort-wchar
581KBUILD_CFLAGS += -funsigned-char
582KBUILD_CFLAGS += -fno-common
583KBUILD_CFLAGS += -fno-PIE
584KBUILD_CFLAGS += -fno-strict-aliasing
585
586KBUILD_CPPFLAGS := -D__KERNEL__
587KBUILD_RUSTFLAGS := $(rust_common_flags) \
588 -Cpanic=abort -Cembed-bitcode=n -Clto=n \
589 -Cforce-unwind-tables=n -Ccodegen-units=1 \
590 -Csymbol-mangling-version=v0 \
591 -Crelocation-model=static \
592 -Zfunction-sections=n \
593 -Wclippy::float_arithmetic
594
595KBUILD_AFLAGS_KERNEL :=
596KBUILD_CFLAGS_KERNEL :=
597KBUILD_RUSTFLAGS_KERNEL :=
598KBUILD_AFLAGS_MODULE := -DMODULE
599KBUILD_CFLAGS_MODULE := -DMODULE
600KBUILD_RUSTFLAGS_MODULE := --cfg MODULE
601KBUILD_LDFLAGS_MODULE :=
602KBUILD_LDFLAGS :=
603CLANG_FLAGS :=
604
605ifeq ($(KBUILD_CLIPPY),1)
606 RUSTC_OR_CLIPPY_QUIET := CLIPPY
607 RUSTC_OR_CLIPPY = $(CLIPPY_DRIVER)
608else
609 RUSTC_OR_CLIPPY_QUIET := RUSTC
610 RUSTC_OR_CLIPPY = $(RUSTC)
611endif
612
613# Allows the usage of unstable features in stable compilers.
614export RUSTC_BOOTSTRAP := 1
615
616# Allows finding `.clippy.toml` in out-of-srctree builds.
617export CLIPPY_CONF_DIR := $(srctree)
618
619export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG
620export RUSTC RUSTDOC RUSTFMT RUSTC_OR_CLIPPY_QUIET RUSTC_OR_CLIPPY BINDGEN
621export HOSTRUSTC KBUILD_HOSTRUSTFLAGS
622export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
623export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
624export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
625export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS KBUILD_PROCMACROLDFLAGS LDFLAGS_MODULE
626export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS
627
628export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
629export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
630export KBUILD_RUSTFLAGS RUSTFLAGS_KERNEL RUSTFLAGS_MODULE
631export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
632export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_RUSTFLAGS_MODULE KBUILD_LDFLAGS_MODULE
633export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL KBUILD_RUSTFLAGS_KERNEL
634
635# Files to ignore in find ... statements
636
637export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o \
638 -name CVS -o -name .pc -o -name .hg -o -name .git \) \
639 -prune -o
640
641# ===========================================================================
642# Rules shared between *config targets and build targets
643
644# Basic helpers built in scripts/basic/
645PHONY += scripts_basic
646scripts_basic:
647 $(Q)$(MAKE) $(build)=scripts/basic
648
649PHONY += outputmakefile
650ifdef building_out_of_srctree
651# Before starting out-of-tree build, make sure the source tree is clean.
652# outputmakefile generates a Makefile in the output directory, if using a
653# separate output directory. This allows convenient use of make in the
654# output directory.
655# At the same time when output Makefile generated, generate .gitignore to
656# ignore whole output directory
657
658ifdef KBUILD_EXTMOD
659print_env_for_makefile = \
660 echo "export KBUILD_OUTPUT = $(objtree)"; \
661 echo "export KBUILD_EXTMOD = $(realpath $(srcroot))" ; \
662 echo "export KBUILD_EXTMOD_OUTPUT = $(CURDIR)"
663else
664print_env_for_makefile = \
665 echo "export KBUILD_OUTPUT = $(CURDIR)"
666endif
667
668quiet_cmd_makefile = GEN Makefile
669 cmd_makefile = { \
670 echo "\# Automatically generated by $(abs_srctree)/Makefile: don't edit"; \
671 $(print_env_for_makefile); \
672 echo "include $(abs_srctree)/Makefile"; \
673 } > Makefile
674
675outputmakefile:
676ifeq ($(KBUILD_EXTMOD),)
677 @if [ -f $(srctree)/.config -o \
678 -d $(srctree)/include/config -o \
679 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
680 echo >&2 "***"; \
681 echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
682 echo >&2 "*** in $(abs_srctree)";\
683 echo >&2 "***"; \
684 false; \
685 fi
686else
687 @if [ -f $(srcroot)/modules.order ]; then \
688 echo >&2 "***"; \
689 echo >&2 "*** The external module source tree is not clean."; \
690 echo >&2 "*** Please run 'make -C $(abs_srctree) M=$(realpath $(srcroot)) clean'"; \
691 echo >&2 "***"; \
692 false; \
693 fi
694endif
695 $(Q)ln -fsn $(srcroot) source
696 $(call cmd,makefile)
697 $(Q)test -e .gitignore || \
698 { echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
699endif
700
701# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
702# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
703# CC_VERSION_TEXT and RUSTC_VERSION_TEXT are referenced from Kconfig (so they
704# need export), and from include/config/auto.conf.cmd to detect the compiler
705# upgrade.
706CC_VERSION_TEXT = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1))
707RUSTC_VERSION_TEXT = $(subst $(pound),,$(shell $(RUSTC) --version 2>/dev/null))
708
709ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
710include $(srctree)/scripts/Makefile.clang
711endif
712
713# Include this also for config targets because some architectures need
714# cc-cross-prefix to determine CROSS_COMPILE.
715ifdef need-compiler
716include $(srctree)/scripts/Makefile.compiler
717endif
718
719ifdef config-build
720# ===========================================================================
721# *config targets only - make sure prerequisites are updated, and descend
722# in scripts/kconfig to make the *config target
723
724# Read arch-specific Makefile to set KBUILD_DEFCONFIG as needed.
725# KBUILD_DEFCONFIG may point out an alternative default configuration
726# used for 'make defconfig'
727include $(srctree)/arch/$(SRCARCH)/Makefile
728export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT RUSTC_VERSION_TEXT
729
730config: outputmakefile scripts_basic FORCE
731 $(Q)$(MAKE) $(build)=scripts/kconfig $@
732
733%config: outputmakefile scripts_basic FORCE
734 $(Q)$(MAKE) $(build)=scripts/kconfig $@
735
736else #!config-build
737# ===========================================================================
738# Build targets only - this includes vmlinux, arch-specific targets, clean
739# targets and others. In general all targets except *config targets.
740
741# If building an external module we do not care about the all: rule
742# but instead __all depend on modules
743PHONY += all
744ifeq ($(KBUILD_EXTMOD),)
745__all: all
746else
747__all: modules
748endif
749
750targets :=
751
752# Decide whether to build built-in, modular, or both.
753# Normally, just do built-in.
754
755KBUILD_MODULES :=
756KBUILD_BUILTIN := 1
757
758# If we have only "make modules", don't compile built-in objects.
759ifeq ($(MAKECMDGOALS),modules)
760 KBUILD_BUILTIN :=
761endif
762
763# If we have "make <whatever> modules", compile modules
764# in addition to whatever we do anyway.
765# Just "make" or "make all" shall build modules as well
766
767ifneq ($(filter all modules nsdeps compile_commands.json clang-%,$(MAKECMDGOALS)),)
768 KBUILD_MODULES := 1
769endif
770
771ifeq ($(MAKECMDGOALS),)
772 KBUILD_MODULES := 1
773endif
774
775export KBUILD_MODULES KBUILD_BUILTIN
776
777ifdef need-config
778include $(objtree)/include/config/auto.conf
779endif
780
781ifeq ($(KBUILD_EXTMOD),)
782# Objects we will link into vmlinux / subdirs we need to visit
783core-y :=
784drivers-y :=
785libs-y := lib/
786endif # KBUILD_EXTMOD
787
788# The all: target is the default when no target is given on the
789# command line.
790# This allow a user to issue only 'make' to build a kernel including modules
791# Defaults to vmlinux, but the arch makefile usually adds further targets
792all: vmlinux
793
794CFLAGS_GCOV := -fprofile-arcs -ftest-coverage
795ifdef CONFIG_CC_IS_GCC
796CFLAGS_GCOV += -fno-tree-loop-im
797endif
798export CFLAGS_GCOV
799
800# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
801ifdef CONFIG_FUNCTION_TRACER
802 CC_FLAGS_FTRACE := -pg
803endif
804
805include $(srctree)/arch/$(SRCARCH)/Makefile
806
807ifdef need-config
808ifdef may-sync-config
809# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
810# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
811# because some architectures define CROSS_COMPILE there.
812include include/config/auto.conf.cmd
813
814$(KCONFIG_CONFIG):
815 @echo >&2 '***'
816 @echo >&2 '*** Configuration file "$@" not found!'
817 @echo >&2 '***'
818 @echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
819 @echo >&2 '*** "make menuconfig" or "make xconfig").'
820 @echo >&2 '***'
821 @/bin/false
822
823# The actual configuration files used during the build are stored in
824# include/generated/ and include/config/. Update them if .config is newer than
825# include/config/auto.conf (which mirrors .config).
826#
827# This exploits the 'multi-target pattern rule' trick.
828# The syncconfig should be executed only once to make all the targets.
829# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
830#
831# Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
832# so you cannot notice that Kconfig is waiting for the user input.
833%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h %/generated/rustc_cfg: $(KCONFIG_CONFIG)
834 $(Q)$(kecho) " SYNC $@"
835 $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
836else # !may-sync-config
837# External modules and some install targets need include/generated/autoconf.h
838# and include/config/auto.conf but do not care if they are up-to-date.
839# Use auto.conf to show the error message
840
841checked-configs := $(addprefix $(objtree)/, include/generated/autoconf.h include/generated/rustc_cfg include/config/auto.conf)
842missing-configs := $(filter-out $(wildcard $(checked-configs)), $(checked-configs))
843
844ifdef missing-configs
845PHONY += $(objtree)/include/config/auto.conf
846
847$(objtree)/include/config/auto.conf:
848 @echo >&2 '***'
849 @echo >&2 '*** ERROR: Kernel configuration is invalid. The following files are missing:'
850 @printf >&2 '*** - %s\n' $(missing-configs)
851 @echo >&2 '*** Run "make oldconfig && make prepare" on kernel source to fix it.'
852 @echo >&2 '***'
853 @/bin/false
854endif
855
856endif # may-sync-config
857endif # need-config
858
859KBUILD_CFLAGS += -fno-delete-null-pointer-checks
860
861ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
862KBUILD_CFLAGS += -O2
863KBUILD_RUSTFLAGS += -Copt-level=2
864else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
865KBUILD_CFLAGS += -Os
866KBUILD_RUSTFLAGS += -Copt-level=s
867endif
868
869# Always set `debug-assertions` and `overflow-checks` because their default
870# depends on `opt-level` and `debug-assertions`, respectively.
871KBUILD_RUSTFLAGS += -Cdebug-assertions=$(if $(CONFIG_RUST_DEBUG_ASSERTIONS),y,n)
872KBUILD_RUSTFLAGS += -Coverflow-checks=$(if $(CONFIG_RUST_OVERFLOW_CHECKS),y,n)
873
874# Tell gcc to never replace conditional load with a non-conditional one
875ifdef CONFIG_CC_IS_GCC
876# gcc-10 renamed --param=allow-store-data-races=0 to
877# -fno-allow-store-data-races.
878KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
879KBUILD_CFLAGS += $(call cc-option,-fno-allow-store-data-races)
880endif
881
882ifdef CONFIG_READABLE_ASM
883# Disable optimizations that make assembler listings hard to read.
884# reorder blocks reorders the control in the function
885# ipa clone creates specialized cloned functions
886# partial inlining inlines only parts of functions
887KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
888endif
889
890stackp-flags-y := -fno-stack-protector
891stackp-flags-$(CONFIG_STACKPROTECTOR) := -fstack-protector
892stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG) := -fstack-protector-strong
893
894KBUILD_CFLAGS += $(stackp-flags-y)
895
896KBUILD_RUSTFLAGS-$(CONFIG_WERROR) += -Dwarnings
897KBUILD_RUSTFLAGS += $(KBUILD_RUSTFLAGS-y)
898
899ifdef CONFIG_FRAME_POINTER
900KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
901KBUILD_RUSTFLAGS += -Cforce-frame-pointers=y
902else
903# Some targets (ARM with Thumb2, for example), can't be built with frame
904# pointers. For those, we don't have FUNCTION_TRACER automatically
905# select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
906# incompatible with -fomit-frame-pointer with current GCC, so we don't use
907# -fomit-frame-pointer with FUNCTION_TRACER.
908# In the Rust target specification, "frame-pointer" is set explicitly
909# to "may-omit".
910ifndef CONFIG_FUNCTION_TRACER
911KBUILD_CFLAGS += -fomit-frame-pointer
912endif
913endif
914
915# Initialize all stack variables with a 0xAA pattern.
916ifdef CONFIG_INIT_STACK_ALL_PATTERN
917KBUILD_CFLAGS += -ftrivial-auto-var-init=pattern
918endif
919
920# Initialize all stack variables with a zero value.
921ifdef CONFIG_INIT_STACK_ALL_ZERO
922KBUILD_CFLAGS += -ftrivial-auto-var-init=zero
923ifdef CONFIG_CC_HAS_AUTO_VAR_INIT_ZERO_ENABLER
924# https://github.com/llvm/llvm-project/issues/44842
925CC_AUTO_VAR_INIT_ZERO_ENABLER := -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
926export CC_AUTO_VAR_INIT_ZERO_ENABLER
927KBUILD_CFLAGS += $(CC_AUTO_VAR_INIT_ZERO_ENABLER)
928endif
929endif
930
931# While VLAs have been removed, GCC produces unreachable stack probes
932# for the randomize_kstack_offset feature. Disable it for all compilers.
933KBUILD_CFLAGS += $(call cc-option, -fno-stack-clash-protection)
934
935# Clear used registers at func exit (to reduce data lifetime and ROP gadgets).
936ifdef CONFIG_ZERO_CALL_USED_REGS
937KBUILD_CFLAGS += -fzero-call-used-regs=used-gpr
938endif
939
940ifdef CONFIG_FUNCTION_TRACER
941ifdef CONFIG_FTRACE_MCOUNT_USE_CC
942 CC_FLAGS_FTRACE += -mrecord-mcount
943 ifdef CONFIG_HAVE_NOP_MCOUNT
944 ifeq ($(call cc-option-yn, -mnop-mcount),y)
945 CC_FLAGS_FTRACE += -mnop-mcount
946 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
947 endif
948 endif
949endif
950ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
951 ifdef CONFIG_HAVE_OBJTOOL_NOP_MCOUNT
952 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
953 endif
954endif
955ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
956 ifdef CONFIG_HAVE_C_RECORDMCOUNT
957 BUILD_C_RECORDMCOUNT := y
958 export BUILD_C_RECORDMCOUNT
959 endif
960endif
961ifdef CONFIG_HAVE_FENTRY
962 # s390-linux-gnu-gcc did not support -mfentry until gcc-9.
963 ifeq ($(call cc-option-yn, -mfentry),y)
964 CC_FLAGS_FTRACE += -mfentry
965 CC_FLAGS_USING += -DCC_USING_FENTRY
966 endif
967endif
968export CC_FLAGS_FTRACE
969KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
970KBUILD_AFLAGS += $(CC_FLAGS_USING)
971endif
972
973# We trigger additional mismatches with less inlining
974ifdef CONFIG_DEBUG_SECTION_MISMATCH
975KBUILD_CFLAGS += -fno-inline-functions-called-once
976endif
977
978# `rustc`'s `-Zfunction-sections` applies to data too (as of 1.59.0).
979ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
980KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
981KBUILD_RUSTFLAGS_KERNEL += -Zfunction-sections=y
982LDFLAGS_vmlinux += --gc-sections
983endif
984
985ifdef CONFIG_SHADOW_CALL_STACK
986ifndef CONFIG_DYNAMIC_SCS
987CC_FLAGS_SCS := -fsanitize=shadow-call-stack
988KBUILD_CFLAGS += $(CC_FLAGS_SCS)
989KBUILD_RUSTFLAGS += -Zsanitizer=shadow-call-stack
990endif
991export CC_FLAGS_SCS
992endif
993
994ifdef CONFIG_LTO_CLANG
995ifdef CONFIG_LTO_CLANG_THIN
996CC_FLAGS_LTO := -flto=thin -fsplit-lto-unit
997else
998CC_FLAGS_LTO := -flto
999endif
1000CC_FLAGS_LTO += -fvisibility=hidden
1001
1002# Limit inlining across translation units to reduce binary size
1003KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
1004endif
1005
1006ifdef CONFIG_LTO
1007KBUILD_CFLAGS += -fno-lto $(CC_FLAGS_LTO)
1008KBUILD_AFLAGS += -fno-lto
1009export CC_FLAGS_LTO
1010endif
1011
1012ifdef CONFIG_CFI_CLANG
1013CC_FLAGS_CFI := -fsanitize=kcfi
1014ifdef CONFIG_CFI_ICALL_NORMALIZE_INTEGERS
1015 CC_FLAGS_CFI += -fsanitize-cfi-icall-experimental-normalize-integers
1016endif
1017ifdef CONFIG_RUST
1018 # Always pass -Zsanitizer-cfi-normalize-integers as CONFIG_RUST selects
1019 # CONFIG_CFI_ICALL_NORMALIZE_INTEGERS.
1020 RUSTC_FLAGS_CFI := -Zsanitizer=kcfi -Zsanitizer-cfi-normalize-integers
1021 KBUILD_RUSTFLAGS += $(RUSTC_FLAGS_CFI)
1022 export RUSTC_FLAGS_CFI
1023endif
1024KBUILD_CFLAGS += $(CC_FLAGS_CFI)
1025export CC_FLAGS_CFI
1026endif
1027
1028# Architectures can define flags to add/remove for floating-point support
1029CC_FLAGS_FPU += -D_LINUX_FPU_COMPILATION_UNIT
1030export CC_FLAGS_FPU
1031export CC_FLAGS_NO_FPU
1032
1033ifneq ($(CONFIG_FUNCTION_ALIGNMENT),0)
1034# Set the minimal function alignment. Use the newer GCC option
1035# -fmin-function-alignment if it is available, or fall back to -falign-funtions.
1036# See also CONFIG_CC_HAS_SANE_FUNCTION_ALIGNMENT.
1037ifdef CONFIG_CC_HAS_MIN_FUNCTION_ALIGNMENT
1038KBUILD_CFLAGS += -fmin-function-alignment=$(CONFIG_FUNCTION_ALIGNMENT)
1039else
1040KBUILD_CFLAGS += -falign-functions=$(CONFIG_FUNCTION_ALIGNMENT)
1041endif
1042endif
1043
1044# arch Makefile may override CC so keep this after arch Makefile is included
1045NOSTDINC_FLAGS += -nostdinc
1046
1047# To gain proper coverage for CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE,
1048# the kernel uses only C99 flexible arrays for dynamically sized trailing
1049# arrays. Enforce this for everything that may examine structure sizes and
1050# perform bounds checking.
1051KBUILD_CFLAGS += $(call cc-option, -fstrict-flex-arrays=3)
1052
1053#Currently, disable -Wstringop-overflow for GCC 11, globally.
1054KBUILD_CFLAGS-$(CONFIG_CC_NO_STRINGOP_OVERFLOW) += $(call cc-option, -Wno-stringop-overflow)
1055KBUILD_CFLAGS-$(CONFIG_CC_STRINGOP_OVERFLOW) += $(call cc-option, -Wstringop-overflow)
1056
1057# disable invalid "can't wrap" optimizations for signed / pointers
1058KBUILD_CFLAGS += -fno-strict-overflow
1059
1060# Make sure -fstack-check isn't enabled (like gentoo apparently did)
1061KBUILD_CFLAGS += -fno-stack-check
1062
1063# conserve stack if available
1064ifdef CONFIG_CC_IS_GCC
1065KBUILD_CFLAGS += -fconserve-stack
1066endif
1067
1068# change __FILE__ to the relative path to the source directory
1069ifdef building_out_of_srctree
1070KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srcroot)/=)
1071endif
1072
1073# include additional Makefiles when needed
1074include-y := scripts/Makefile.extrawarn
1075include-$(CONFIG_DEBUG_INFO) += scripts/Makefile.debug
1076include-$(CONFIG_DEBUG_INFO_BTF)+= scripts/Makefile.btf
1077include-$(CONFIG_KASAN) += scripts/Makefile.kasan
1078include-$(CONFIG_KCSAN) += scripts/Makefile.kcsan
1079include-$(CONFIG_KMSAN) += scripts/Makefile.kmsan
1080include-$(CONFIG_UBSAN) += scripts/Makefile.ubsan
1081include-$(CONFIG_KCOV) += scripts/Makefile.kcov
1082include-$(CONFIG_RANDSTRUCT) += scripts/Makefile.randstruct
1083include-$(CONFIG_AUTOFDO_CLANG) += scripts/Makefile.autofdo
1084include-$(CONFIG_PROPELLER_CLANG) += scripts/Makefile.propeller
1085include-$(CONFIG_GCC_PLUGINS) += scripts/Makefile.gcc-plugins
1086
1087include $(addprefix $(srctree)/, $(include-y))
1088
1089# scripts/Makefile.gcc-plugins is intentionally included last.
1090# Do not add $(call cc-option,...) below this line. When you build the kernel
1091# from the clean source tree, the GCC plugins do not exist at this point.
1092
1093# Add user supplied CPPFLAGS, AFLAGS, CFLAGS and RUSTFLAGS as the last assignments
1094KBUILD_CPPFLAGS += $(KCPPFLAGS)
1095KBUILD_AFLAGS += $(KAFLAGS)
1096KBUILD_CFLAGS += $(KCFLAGS)
1097KBUILD_RUSTFLAGS += $(KRUSTFLAGS)
1098
1099KBUILD_LDFLAGS_MODULE += --build-id=sha1
1100LDFLAGS_vmlinux += --build-id=sha1
1101
1102KBUILD_LDFLAGS += -z noexecstack
1103ifeq ($(CONFIG_LD_IS_BFD),y)
1104KBUILD_LDFLAGS += $(call ld-option,--no-warn-rwx-segments)
1105endif
1106
1107ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1108LDFLAGS_vmlinux += -X
1109endif
1110
1111ifeq ($(CONFIG_RELR),y)
1112# ld.lld before 15 did not support -z pack-relative-relocs.
1113LDFLAGS_vmlinux += $(call ld-option,--pack-dyn-relocs=relr,-z pack-relative-relocs)
1114endif
1115
1116# We never want expected sections to be placed heuristically by the
1117# linker. All sections should be explicitly named in the linker script.
1118ifdef CONFIG_LD_ORPHAN_WARN
1119LDFLAGS_vmlinux += --orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL)
1120endif
1121
1122# Align the bit size of userspace programs with the kernel
1123KBUILD_USERCFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS))
1124KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS))
1125
1126# userspace programs are linked via the compiler, use the correct linker
1127ifeq ($(CONFIG_CC_IS_CLANG)$(CONFIG_LD_IS_LLD),yy)
1128KBUILD_USERLDFLAGS += --ld-path=$(LD)
1129endif
1130
1131# make the checker run with the right architecture
1132CHECKFLAGS += --arch=$(ARCH)
1133
1134# insure the checker run with the right endianness
1135CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1136
1137# the checker needs the correct machine size
1138CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1139
1140# Default kernel image to build when no specific target is given.
1141# KBUILD_IMAGE may be overruled on the command line or
1142# set in the environment
1143# Also any assignments in arch/$(ARCH)/Makefile take precedence over
1144# this default value
1145export KBUILD_IMAGE ?= vmlinux
1146
1147#
1148# INSTALL_PATH specifies where to place the updated kernel and system map
1149# images. Default is /boot, but you can set it to other values
1150export INSTALL_PATH ?= /boot
1151
1152#
1153# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1154# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1155# an argument if needed. Otherwise it defaults to the kernel install path
1156#
1157export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1158
1159#
1160# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1161# relocations required by build roots. This is not defined in the
1162# makefile but the argument can be passed to make if needed.
1163#
1164
1165MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1166export MODLIB
1167
1168PHONY += prepare0
1169
1170ifeq ($(KBUILD_EXTMOD),)
1171
1172build-dir := .
1173clean-dirs := $(sort . Documentation \
1174 $(patsubst %/,%,$(filter %/, $(core-) \
1175 $(drivers-) $(libs-))))
1176
1177export ARCH_CORE := $(core-y)
1178export ARCH_LIB := $(filter %/, $(libs-y))
1179export ARCH_DRIVERS := $(drivers-y) $(drivers-m)
1180# Externally visible symbols (used by link-vmlinux.sh)
1181
1182KBUILD_VMLINUX_OBJS := ./built-in.a
1183ifdef CONFIG_MODULES
1184KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1185KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1186else
1187KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1188endif
1189
1190export KBUILD_VMLINUX_LIBS
1191export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
1192
1193ifdef CONFIG_TRIM_UNUSED_KSYMS
1194# For the kernel to actually contain only the needed exported symbols,
1195# we have to build modules as well to determine what those symbols are.
1196KBUILD_MODULES := 1
1197endif
1198
1199# '$(AR) mPi' needs 'T' to workaround the bug of llvm-ar <= 14
1200quiet_cmd_ar_vmlinux.a = AR $@
1201 cmd_ar_vmlinux.a = \
1202 rm -f $@; \
1203 $(AR) cDPrST $@ $(KBUILD_VMLINUX_OBJS); \
1204 $(AR) mPiT $$($(AR) t $@ | sed -n 1p) $@ $$($(AR) t $@ | grep -F -f $(srctree)/scripts/head-object-list.txt)
1205
1206targets += vmlinux.a
1207vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt FORCE
1208 $(call if_changed,ar_vmlinux.a)
1209
1210PHONY += vmlinux_o
1211vmlinux_o: vmlinux.a $(KBUILD_VMLINUX_LIBS)
1212 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o
1213
1214vmlinux.o modules.builtin.modinfo modules.builtin: vmlinux_o
1215 @:
1216
1217PHONY += vmlinux
1218# LDFLAGS_vmlinux in the top Makefile defines linker flags for the top vmlinux,
1219# not for decompressors. LDFLAGS_vmlinux in arch/*/boot/compressed/Makefile is
1220# unrelated; the decompressors just happen to have the same base name,
1221# arch/*/boot/compressed/vmlinux.
1222# Export LDFLAGS_vmlinux only to scripts/Makefile.vmlinux.
1223#
1224# _LDFLAGS_vmlinux is a workaround for the 'private export' bug:
1225# https://savannah.gnu.org/bugs/?61463
1226# For Make > 4.4, the following simple code will work:
1227# vmlinux: private export LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1228vmlinux: private _LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1229vmlinux: export LDFLAGS_vmlinux = $(_LDFLAGS_vmlinux)
1230vmlinux: vmlinux.o $(KBUILD_LDS) modpost
1231 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux
1232
1233# The actual objects are generated when descending,
1234# make sure no implicit rule kicks in
1235$(sort $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)): . ;
1236
1237ifeq ($(origin KERNELRELEASE),file)
1238filechk_kernel.release = $(srctree)/scripts/setlocalversion $(srctree)
1239else
1240filechk_kernel.release = echo $(KERNELRELEASE)
1241endif
1242
1243# Store (new) KERNELRELEASE string in include/config/kernel.release
1244include/config/kernel.release: FORCE
1245 $(call filechk,kernel.release)
1246
1247# Additional helpers built in scripts/
1248# Carefully list dependencies so we do not try to build scripts twice
1249# in parallel
1250PHONY += scripts
1251scripts: scripts_basic scripts_dtc
1252 $(Q)$(MAKE) $(build)=$(@)
1253
1254# Things we need to do before we recursively start building the kernel
1255# or the modules are listed in "prepare".
1256# A multi level approach is used. prepareN is processed before prepareN-1.
1257# archprepare is used in arch Makefiles and when processed asm symlink,
1258# version.h and scripts_basic is processed / created.
1259
1260PHONY += prepare archprepare
1261
1262archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1263 asm-generic $(version_h) include/generated/utsrelease.h \
1264 include/generated/compile.h include/generated/autoconf.h \
1265 include/generated/rustc_cfg remove-stale-files
1266
1267prepare0: archprepare
1268 $(Q)$(MAKE) $(build)=scripts/mod
1269 $(Q)$(MAKE) $(build)=. prepare
1270
1271# All the preparing..
1272prepare: prepare0
1273ifdef CONFIG_RUST
1274 +$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh
1275 $(Q)$(MAKE) $(build)=rust
1276endif
1277
1278PHONY += remove-stale-files
1279remove-stale-files:
1280 $(Q)$(srctree)/scripts/remove-stale-files
1281
1282# Support for using generic headers in asm-generic
1283asm-generic := -f $(srctree)/scripts/Makefile.asm-headers obj
1284
1285PHONY += asm-generic uapi-asm-generic
1286asm-generic: uapi-asm-generic
1287 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1288 generic=include/asm-generic
1289uapi-asm-generic:
1290 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1291 generic=include/uapi/asm-generic
1292
1293# Generate some files
1294# ---------------------------------------------------------------------------
1295
1296# KERNELRELEASE can change from a few different places, meaning version.h
1297# needs to be updated, so this check is forced on all builds
1298
1299uts_len := 64
1300define filechk_utsrelease.h
1301 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1302 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1303 exit 1; \
1304 fi; \
1305 echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1306endef
1307
1308define filechk_version.h
1309 if [ $(SUBLEVEL) -gt 255 ]; then \
1310 echo \#define LINUX_VERSION_CODE $(shell \
1311 expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1312 else \
1313 echo \#define LINUX_VERSION_CODE $(shell \
1314 expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1315 fi; \
1316 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + \
1317 ((c) > 255 ? 255 : (c)))'; \
1318 echo \#define LINUX_VERSION_MAJOR $(VERSION); \
1319 echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL); \
1320 echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1321endef
1322
1323$(version_h): private PATCHLEVEL := $(or $(PATCHLEVEL), 0)
1324$(version_h): private SUBLEVEL := $(or $(SUBLEVEL), 0)
1325$(version_h): FORCE
1326 $(call filechk,version.h)
1327
1328include/generated/utsrelease.h: include/config/kernel.release FORCE
1329 $(call filechk,utsrelease.h)
1330
1331filechk_compile.h = $(srctree)/scripts/mkcompile_h \
1332 "$(UTS_MACHINE)" "$(CONFIG_CC_VERSION_TEXT)" "$(LD)"
1333
1334include/generated/compile.h: FORCE
1335 $(call filechk,compile.h)
1336
1337PHONY += headerdep
1338headerdep:
1339 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1340 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1341
1342# ---------------------------------------------------------------------------
1343# Kernel headers
1344
1345#Default location for installed headers
1346export INSTALL_HDR_PATH = $(objtree)/usr
1347
1348quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1349 cmd_headers_install = \
1350 mkdir -p $(INSTALL_HDR_PATH); \
1351 rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1352 usr/include $(INSTALL_HDR_PATH)
1353
1354PHONY += headers_install
1355headers_install: headers
1356 $(call cmd,headers_install)
1357
1358PHONY += archheaders archscripts
1359
1360hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1361
1362PHONY += headers
1363headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1364 $(if $(filter um, $(SRCARCH)), $(error Headers not exportable for UML))
1365 $(Q)$(MAKE) $(hdr-inst)=include/uapi
1366 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1367
1368ifdef CONFIG_HEADERS_INSTALL
1369prepare: headers
1370endif
1371
1372PHONY += scripts_unifdef
1373scripts_unifdef: scripts_basic
1374 $(Q)$(MAKE) $(build)=scripts scripts/unifdef
1375
1376PHONY += scripts_gen_packed_field_checks
1377scripts_gen_packed_field_checks: scripts_basic
1378 $(Q)$(MAKE) $(build)=scripts scripts/gen_packed_field_checks
1379
1380# ---------------------------------------------------------------------------
1381# Install
1382
1383# Many distributions have the custom install script, /sbin/installkernel.
1384# If DKMS is installed, 'make install' will eventually recurse back
1385# to this Makefile to build and install external modules.
1386# Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
1387
1388quiet_cmd_install = INSTALL $(INSTALL_PATH)
1389 cmd_install = unset sub_make_done; $(srctree)/scripts/install.sh
1390
1391# ---------------------------------------------------------------------------
1392# vDSO install
1393
1394PHONY += vdso_install
1395vdso_install: export INSTALL_FILES = $(vdso-install-y)
1396vdso_install:
1397 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vdsoinst
1398
1399# ---------------------------------------------------------------------------
1400# Tools
1401
1402ifdef CONFIG_OBJTOOL
1403prepare: tools/objtool
1404endif
1405
1406ifdef CONFIG_BPF
1407ifdef CONFIG_DEBUG_INFO_BTF
1408prepare: tools/bpf/resolve_btfids
1409endif
1410endif
1411
1412# The tools build system is not a part of Kbuild and tends to introduce
1413# its own unique issues. If you need to integrate a new tool into Kbuild,
1414# please consider locating that tool outside the tools/ tree and using the
1415# standard Kbuild "hostprogs" syntax instead of adding a new tools/* entry
1416# here. See Documentation/kbuild/makefiles.rst for details.
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
1429tools/: FORCE
1430 $(Q)mkdir -p $(objtree)/tools
1431 $(Q)$(MAKE) LDFLAGS= O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1432
1433tools/%: FORCE
1434 $(Q)mkdir -p $(objtree)/tools
1435 $(Q)$(MAKE) LDFLAGS= O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1436
1437# ---------------------------------------------------------------------------
1438# Kernel selftest
1439
1440PHONY += kselftest
1441kselftest: headers
1442 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1443
1444kselftest-%: headers FORCE
1445 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1446
1447PHONY += kselftest-merge
1448kselftest-merge:
1449 $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1450 $(Q)find $(srctree)/tools/testing/selftests -name config -o -name config.$(UTS_MACHINE) | \
1451 xargs $(srctree)/scripts/kconfig/merge_config.sh -y -m $(objtree)/.config
1452 $(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1453
1454# ---------------------------------------------------------------------------
1455# Devicetree files
1456
1457ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1458dtstree := arch/$(SRCARCH)/boot/dts
1459endif
1460
1461ifneq ($(dtstree),)
1462
1463%.dtb: dtbs_prepare
1464 $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1465
1466%.dtbo: dtbs_prepare
1467 $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1468
1469PHONY += dtbs dtbs_prepare dtbs_install dtbs_check
1470dtbs: dtbs_prepare
1471 $(Q)$(MAKE) $(build)=$(dtstree) need-dtbslist=1
1472
1473# include/config/kernel.release is actually needed when installing DTBs because
1474# INSTALL_DTBS_PATH contains $(KERNELRELEASE). However, we do not want to make
1475# dtbs_install depend on it as dtbs_install may run as root.
1476dtbs_prepare: include/config/kernel.release scripts_dtc
1477
1478ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1479export CHECK_DTBS=y
1480endif
1481
1482ifneq ($(CHECK_DTBS),)
1483dtbs_prepare: dt_binding_schemas
1484endif
1485
1486dtbs_check: dtbs
1487
1488dtbs_install:
1489 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.dtbinst obj=$(dtstree)
1490
1491ifdef CONFIG_OF_EARLY_FLATTREE
1492all: dtbs
1493endif
1494
1495ifdef CONFIG_GENERIC_BUILTIN_DTB
1496vmlinux: dtbs
1497endif
1498
1499endif
1500
1501PHONY += scripts_dtc
1502scripts_dtc: scripts_basic
1503 $(Q)$(MAKE) $(build)=scripts/dtc
1504
1505ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1506export CHECK_DTBS=y
1507endif
1508
1509PHONY += dt_binding_check dt_binding_schemas
1510dt_binding_check: dt_binding_schemas scripts_dtc
1511 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1512
1513dt_binding_schemas:
1514 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1515
1516PHONY += dt_compatible_check
1517dt_compatible_check: dt_binding_schemas
1518 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1519
1520# ---------------------------------------------------------------------------
1521# Modules
1522
1523ifdef CONFIG_MODULES
1524
1525# By default, build modules as well
1526
1527all: modules
1528
1529# When we're building modules with modversions, we need to consider
1530# the built-in objects during the descend as well, in order to
1531# make sure the checksums are up to date before we record them.
1532ifdef CONFIG_MODVERSIONS
1533 KBUILD_BUILTIN := 1
1534endif
1535
1536# Build modules
1537#
1538
1539# *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFO_BTF_MODULES
1540# is an exception.
1541ifdef CONFIG_DEBUG_INFO_BTF_MODULES
1542KBUILD_BUILTIN := 1
1543modules: vmlinux
1544endif
1545
1546modules: modules_prepare
1547
1548# Target to prepare building external modules
1549modules_prepare: prepare
1550 $(Q)$(MAKE) $(build)=scripts scripts/module.lds
1551
1552endif # CONFIG_MODULES
1553
1554###
1555# Cleaning is done on three levels.
1556# make clean Delete most generated files
1557# Leave enough to build external modules
1558# make mrproper Delete the current configuration, and all generated files
1559# make distclean Remove editor backup files, patch leftover files and the like
1560
1561# Directories & files removed with 'make clean'
1562CLEAN_FILES += vmlinux.symvers modules-only.symvers \
1563 modules.builtin modules.builtin.modinfo modules.nsdeps \
1564 modules.builtin.ranges vmlinux.o.map \
1565 compile_commands.json rust/test \
1566 rust-project.json .vmlinux.objs .vmlinux.export.c \
1567 .builtin-dtbs-list .builtin-dtb.S
1568
1569# Directories & files removed with 'make mrproper'
1570MRPROPER_FILES += include/config include/generated \
1571 arch/$(SRCARCH)/include/generated .objdiff \
1572 debian snap tar-install PKGBUILD pacman \
1573 .config .config.old .version \
1574 Module.symvers \
1575 certs/signing_key.pem \
1576 certs/x509.genkey \
1577 vmlinux-gdb.py \
1578 rpmbuild \
1579 rust/libmacros.so rust/libmacros.dylib
1580
1581# clean - Delete most, but leave enough to build external modules
1582#
1583clean: private rm-files := $(CLEAN_FILES)
1584
1585PHONY += archclean vmlinuxclean
1586
1587vmlinuxclean:
1588 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1589 $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1590
1591clean: archclean vmlinuxclean resolve_btfids_clean
1592
1593# mrproper - Delete all generated files, including .config
1594#
1595mrproper: private rm-files := $(MRPROPER_FILES)
1596mrproper-dirs := $(addprefix _mrproper_,scripts)
1597
1598PHONY += $(mrproper-dirs) mrproper
1599$(mrproper-dirs):
1600 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1601
1602mrproper: clean $(mrproper-dirs)
1603 $(call cmd,rmfiles)
1604 @find . $(RCS_FIND_IGNORE) \
1605 \( -name '*.rmeta' \) \
1606 -type f -print | xargs rm -f
1607
1608# distclean
1609#
1610PHONY += distclean
1611
1612distclean: mrproper
1613 @find . $(RCS_FIND_IGNORE) \
1614 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1615 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1616 -o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1617 -o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1618 -type f -print | xargs rm -f
1619
1620
1621# Packaging of the kernel to various formats
1622# ---------------------------------------------------------------------------
1623
1624%src-pkg: FORCE
1625 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1626%pkg: include/config/kernel.release FORCE
1627 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1628
1629# Brief documentation of the typical targets used
1630# ---------------------------------------------------------------------------
1631
1632boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1633boards := $(sort $(notdir $(boards)))
1634board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1635board-dirs := $(sort $(notdir $(board-dirs:/=)))
1636
1637PHONY += help
1638help:
1639 @echo 'Cleaning targets:'
1640 @echo ' clean - Remove most generated files but keep the config and'
1641 @echo ' enough build support to build external modules'
1642 @echo ' mrproper - Remove all generated files + config + various backup files'
1643 @echo ' distclean - mrproper + remove editor backup and patch files'
1644 @echo ''
1645 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1646 @echo ''
1647 @echo 'Other generic targets:'
1648 @echo ' all - Build all targets marked with [*]'
1649 @echo '* vmlinux - Build the bare kernel'
1650 @echo '* modules - Build all modules'
1651 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1652 @echo ' vdso_install - Install unstripped vdso to INSTALL_MOD_PATH (default: /)'
1653 @echo ' dir/ - Build all files in dir and below'
1654 @echo ' dir/file.[ois] - Build specified target only'
1655 @echo ' dir/file.ll - Build the LLVM assembly file'
1656 @echo ' (requires compiler support for LLVM assembly generation)'
1657 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1658 @echo ' (requires a recent binutils and recent build (System.map))'
1659 @echo ' dir/file.ko - Build module including final link'
1660 @echo ' modules_prepare - Set up for building external modules'
1661 @echo ' tags/TAGS - Generate tags file for editors'
1662 @echo ' cscope - Generate cscope index'
1663 @echo ' gtags - Generate GNU GLOBAL index'
1664 @echo ' kernelrelease - Output the release version string (use with make -s)'
1665 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1666 @echo ' image_name - Output the image name (use with make -s)'
1667 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1668 echo ' (default: $(INSTALL_HDR_PATH))'; \
1669 echo ''
1670 @echo 'Static analysers:'
1671 @echo ' checkstack - Generate a list of stack hogs and consider all functions'
1672 @echo ' with a stack size larger than MINSTACKSIZE (default: 100)'
1673 @echo ' versioncheck - Sanity check on version.h usage'
1674 @echo ' includecheck - Check for duplicate included header files'
1675 @echo ' headerdep - Detect inclusion cycles in headers'
1676 @echo ' coccicheck - Check with Coccinelle'
1677 @echo ' clang-analyzer - Check with clang static analyzer'
1678 @echo ' clang-tidy - Check with clang-tidy'
1679 @echo ''
1680 @echo 'Tools:'
1681 @echo ' nsdeps - Generate missing symbol namespace dependencies'
1682 @echo ''
1683 @echo 'Kernel selftest:'
1684 @echo ' kselftest - Build and run kernel selftest'
1685 @echo ' Build, install, and boot kernel before'
1686 @echo ' running kselftest on it'
1687 @echo ' Run as root for full coverage'
1688 @echo ' kselftest-all - Build kernel selftest'
1689 @echo ' kselftest-install - Build and install kernel selftest'
1690 @echo ' kselftest-clean - Remove all generated kselftest files'
1691 @echo ' kselftest-merge - Merge all the config dependencies of'
1692 @echo ' kselftest to existing .config.'
1693 @echo ''
1694 @echo 'Rust targets:'
1695 @echo ' rustavailable - Checks whether the Rust toolchain is'
1696 @echo ' available and, if not, explains why.'
1697 @echo ' rustfmt - Reformat all the Rust code in the kernel'
1698 @echo ' rustfmtcheck - Checks if all the Rust code in the kernel'
1699 @echo ' is formatted, printing a diff otherwise.'
1700 @echo ' rustdoc - Generate Rust documentation'
1701 @echo ' (requires kernel .config)'
1702 @echo ' rusttest - Runs the Rust tests'
1703 @echo ' (requires kernel .config; downloads external repos)'
1704 @echo ' rust-analyzer - Generate rust-project.json rust-analyzer support file'
1705 @echo ' (requires kernel .config)'
1706 @echo ' dir/file.[os] - Build specified target only'
1707 @echo ' dir/file.rsi - Build macro expanded source, similar to C preprocessing.'
1708 @echo ' Run with RUSTFMT=n to skip reformatting if needed.'
1709 @echo ' The output is not intended to be compilable.'
1710 @echo ' dir/file.ll - Build the LLVM assembly file'
1711 @echo ''
1712 @$(if $(dtstree), \
1713 echo 'Devicetree:'; \
1714 echo '* dtbs - Build device tree blobs for enabled boards'; \
1715 echo ' dtbs_install - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1716 echo ' dt_binding_check - Validate device tree binding documents and examples'; \
1717 echo ' dt_binding_schemas - Build processed device tree binding schemas'; \
1718 echo ' dtbs_check - Validate device tree source files';\
1719 echo '')
1720
1721 @echo 'Userspace tools targets:'
1722 @echo ' use "make tools/help"'
1723 @echo ' or "cd tools; make help"'
1724 @echo ''
1725 @echo 'Kernel packaging:'
1726 @$(MAKE) -f $(srctree)/scripts/Makefile.package help
1727 @echo ''
1728 @echo 'Documentation targets:'
1729 @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1730 @echo ''
1731 @echo 'Architecture-specific targets ($(SRCARCH)):'
1732 @$(or $(archhelp),\
1733 echo ' No architecture-specific help defined for $(SRCARCH)')
1734 @echo ''
1735 @$(if $(boards), \
1736 $(foreach b, $(boards), \
1737 printf " %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1738 echo '')
1739 @$(if $(board-dirs), \
1740 $(foreach b, $(board-dirs), \
1741 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1742 printf " %-16s - Show all of the above\\n" help-boards; \
1743 echo '')
1744
1745 @echo ' make V=n [targets] 1: verbose build'
1746 @echo ' 2: give reason for rebuild of target'
1747 @echo ' V=1 and V=2 can be combined with V=12'
1748 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1749 @echo ' make C=1 [targets] Check re-compiled c source with $$CHECK'
1750 @echo ' (sparse by default)'
1751 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1752 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1753 @echo ' make W=n [targets] Enable extra build checks, n=1,2,3,c,e where'
1754 @echo ' 1: warnings which may be relevant and do not occur too often'
1755 @echo ' 2: warnings which occur quite often but may still be relevant'
1756 @echo ' 3: more obscure warnings, can most likely be ignored'
1757 @echo ' c: extra checks in the configuration stage (Kconfig)'
1758 @echo ' e: warnings are being treated as errors'
1759 @echo ' Multiple levels can be combined with W=12 or W=123'
1760 @$(if $(dtstree), \
1761 echo ' make CHECK_DTBS=1 [targets] Check all generated dtb files against schema'; \
1762 echo ' This can be applied both to "dtbs" and to individual "foo.dtb" targets' ; \
1763 )
1764 @echo ''
1765 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1766 @echo 'For further info see the ./README file'
1767
1768
1769help-board-dirs := $(addprefix help-,$(board-dirs))
1770
1771help-boards: $(help-board-dirs)
1772
1773boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1774
1775$(help-board-dirs): help-%:
1776 @echo 'Architecture-specific targets ($(SRCARCH) $*):'
1777 @$(if $(boards-per-dir), \
1778 $(foreach b, $(boards-per-dir), \
1779 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1780 echo '')
1781
1782
1783# Documentation targets
1784# ---------------------------------------------------------------------------
1785DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1786 linkcheckdocs dochelp refcheckdocs texinfodocs infodocs
1787PHONY += $(DOC_TARGETS)
1788$(DOC_TARGETS):
1789 $(Q)$(MAKE) $(build)=Documentation $@
1790
1791
1792# Rust targets
1793# ---------------------------------------------------------------------------
1794
1795# "Is Rust available?" target
1796PHONY += rustavailable
1797rustavailable:
1798 +$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh && echo "Rust is available!"
1799
1800# Documentation target
1801#
1802# Using the singular to avoid running afoul of `no-dot-config-targets`.
1803PHONY += rustdoc
1804rustdoc: prepare
1805 $(Q)$(MAKE) $(build)=rust $@
1806
1807# Testing target
1808PHONY += rusttest
1809rusttest: prepare
1810 $(Q)$(MAKE) $(build)=rust $@
1811
1812# Formatting targets
1813PHONY += rustfmt rustfmtcheck
1814
1815rustfmt:
1816 $(Q)find $(srctree) $(RCS_FIND_IGNORE) \
1817 -type f -a -name '*.rs' -a ! -name '*generated*' -print \
1818 | xargs $(RUSTFMT) $(rustfmt_flags)
1819
1820rustfmtcheck: rustfmt_flags = --check
1821rustfmtcheck: rustfmt
1822
1823# Misc
1824# ---------------------------------------------------------------------------
1825
1826PHONY += misc-check
1827misc-check:
1828 $(Q)$(srctree)/scripts/misc-check
1829
1830all: misc-check
1831
1832PHONY += scripts_gdb
1833scripts_gdb: prepare0
1834 $(Q)$(MAKE) $(build)=scripts/gdb
1835 $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1836
1837ifdef CONFIG_GDB_SCRIPTS
1838all: scripts_gdb
1839endif
1840
1841else # KBUILD_EXTMOD
1842
1843filechk_kernel.release = echo $(KERNELRELEASE)
1844
1845###
1846# External module support.
1847# When building external modules the kernel used as basis is considered
1848# read-only, and no consistency checks are made and the make
1849# system is not used on the basis kernel. If updates are required
1850# in the basis kernel ordinary make commands (without M=...) must be used.
1851
1852# We are always building only modules.
1853KBUILD_BUILTIN :=
1854KBUILD_MODULES := 1
1855
1856build-dir := .
1857
1858clean-dirs := .
1859clean: private rm-files := Module.symvers modules.nsdeps compile_commands.json
1860
1861PHONY += prepare
1862# now expand this into a simple variable to reduce the cost of shell evaluations
1863prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT)
1864prepare:
1865 @if [ "$(CC_VERSION_TEXT)" != "$(CONFIG_CC_VERSION_TEXT)" ]; then \
1866 echo >&2 "warning: the compiler differs from the one used to build the kernel"; \
1867 echo >&2 " The kernel was built by: $(CONFIG_CC_VERSION_TEXT)"; \
1868 echo >&2 " You are using: $(CC_VERSION_TEXT)"; \
1869 fi
1870
1871PHONY += help
1872help:
1873 @echo ' Building external modules.'
1874 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1875 @echo ''
1876 @echo ' modules - default target, build the module(s)'
1877 @echo ' modules_install - install the module'
1878 @echo ' clean - remove generated files in module directory only'
1879 @echo ' rust-analyzer - generate rust-project.json rust-analyzer support file'
1880 @echo ''
1881
1882ifndef CONFIG_MODULES
1883modules modules_install: __external_modules_error
1884__external_modules_error:
1885 @echo >&2 '***'
1886 @echo >&2 '*** The present kernel disabled CONFIG_MODULES.'
1887 @echo >&2 '*** You cannot build or install external modules.'
1888 @echo >&2 '***'
1889 @false
1890endif
1891
1892endif # KBUILD_EXTMOD
1893
1894# ---------------------------------------------------------------------------
1895# Modules
1896
1897PHONY += modules modules_install modules_sign modules_prepare
1898
1899modules_install:
1900 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst \
1901 sign-only=$(if $(filter modules_install,$(MAKECMDGOALS)),,y)
1902
1903ifeq ($(CONFIG_MODULE_SIG),y)
1904# modules_sign is a subset of modules_install.
1905# 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1906modules_sign: modules_install
1907 @:
1908else
1909modules_sign:
1910 @echo >&2 '***'
1911 @echo >&2 '*** CONFIG_MODULE_SIG is disabled. You cannot sign modules.'
1912 @echo >&2 '***'
1913 @false
1914endif
1915
1916ifdef CONFIG_MODULES
1917
1918modules.order: $(build-dir)
1919 @:
1920
1921# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
1922# This is solely useful to speed up test compiles.
1923modules: modpost
1924ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1925 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1926endif
1927
1928PHONY += modules_check
1929modules_check: modules.order
1930 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1931
1932else # CONFIG_MODULES
1933
1934modules:
1935 @:
1936
1937KBUILD_MODULES :=
1938
1939endif # CONFIG_MODULES
1940
1941PHONY += modpost
1942modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \
1943 $(if $(KBUILD_MODULES), modules_check)
1944 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1945
1946# Single targets
1947# ---------------------------------------------------------------------------
1948# To build individual files in subdirectories, you can do like this:
1949#
1950# make foo/bar/baz.s
1951#
1952# The supported suffixes for single-target are listed in 'single-targets'
1953#
1954# To build only under specific subdirectories, you can do like this:
1955#
1956# make foo/bar/baz/
1957
1958ifdef single-build
1959
1960# .ko is special because modpost is needed
1961single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1962single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \
1963 $(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko)))
1964
1965$(single-ko): single_modules
1966 @:
1967$(single-no-ko): $(build-dir)
1968 @:
1969
1970# Remove modules.order when done because it is not the real one.
1971PHONY += single_modules
1972single_modules: $(single-no-ko) modules_prepare
1973 $(Q){ $(foreach m, $(single-ko), echo $(m:%.ko=%.o);) } > modules.order
1974 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1975ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1976 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1977endif
1978 $(Q)rm -f modules.order
1979
1980single-goals := $(addprefix $(build-dir)/, $(single-no-ko))
1981
1982KBUILD_MODULES := 1
1983
1984endif
1985
1986prepare: outputmakefile
1987
1988# Preset locale variables to speed up the build process. Limit locale
1989# tweaks to this spot to avoid wrong language settings when running
1990# make menuconfig etc.
1991# Error messages still appears in the original language
1992PHONY += $(build-dir)
1993$(build-dir): prepare
1994 $(Q)$(MAKE) $(build)=$@ need-builtin=1 need-modorder=1 $(single-goals)
1995
1996clean-dirs := $(addprefix _clean_, $(clean-dirs))
1997PHONY += $(clean-dirs) clean
1998$(clean-dirs):
1999 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
2000
2001clean: $(clean-dirs)
2002 $(call cmd,rmfiles)
2003 @find . $(RCS_FIND_IGNORE) \
2004 \( -name '*.[aios]' -o -name '*.rsi' -o -name '*.ko' -o -name '.*.cmd' \
2005 -o -name '*.ko.*' \
2006 -o -name '*.dtb' -o -name '*.dtbo' \
2007 -o -name '*.dtb.S' -o -name '*.dtbo.S' \
2008 -o -name '*.dt.yaml' -o -name 'dtbs-list' \
2009 -o -name '*.dwo' -o -name '*.lst' \
2010 -o -name '*.su' -o -name '*.mod' \
2011 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
2012 -o -name '*.lex.c' -o -name '*.tab.[ch]' \
2013 -o -name '*.asn1.[ch]' \
2014 -o -name '*.symtypes' -o -name 'modules.order' \
2015 -o -name '*.c.[012]*.*' \
2016 -o -name '*.ll' \
2017 -o -name '*.gcno' \
2018 \) -type f -print \
2019 -o -name '.tmp_*' -print \
2020 | xargs rm -rf
2021
2022# Generate tags for editors
2023# ---------------------------------------------------------------------------
2024quiet_cmd_tags = GEN $@
2025 cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
2026
2027tags TAGS cscope gtags: FORCE
2028 $(call cmd,tags)
2029
2030# Generate rust-project.json (a file that describes the structure of non-Cargo
2031# Rust projects) for rust-analyzer (an implementation of the Language Server
2032# Protocol).
2033PHONY += rust-analyzer
2034rust-analyzer:
2035 +$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh
2036ifdef KBUILD_EXTMOD
2037# FIXME: external modules must not descend into a sub-directory of the kernel
2038 $(Q)$(MAKE) $(build)=$(objtree)/rust src=$(srctree)/rust $@
2039else
2040 $(Q)$(MAKE) $(build)=rust $@
2041endif
2042
2043# Script to generate missing namespace dependencies
2044# ---------------------------------------------------------------------------
2045
2046PHONY += nsdeps
2047nsdeps: export KBUILD_NSDEPS=1
2048nsdeps: modules
2049 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
2050
2051# Clang Tooling
2052# ---------------------------------------------------------------------------
2053
2054quiet_cmd_gen_compile_commands = GEN $@
2055 cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
2056
2057compile_commands.json: $(srctree)/scripts/clang-tools/gen_compile_commands.py \
2058 $(if $(KBUILD_EXTMOD),, vmlinux.a $(KBUILD_VMLINUX_LIBS)) \
2059 $(if $(CONFIG_MODULES), modules.order) FORCE
2060 $(call if_changed,gen_compile_commands)
2061
2062targets += compile_commands.json
2063
2064PHONY += clang-tidy clang-analyzer
2065
2066ifdef CONFIG_CC_IS_CLANG
2067quiet_cmd_clang_tools = CHECK $<
2068 cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
2069
2070clang-tidy clang-analyzer: compile_commands.json
2071 $(call cmd,clang_tools)
2072else
2073clang-tidy clang-analyzer:
2074 @echo "$@ requires CC=clang" >&2
2075 @false
2076endif
2077
2078# Scripts to check various things for consistency
2079# ---------------------------------------------------------------------------
2080
2081PHONY += includecheck versioncheck coccicheck
2082
2083includecheck:
2084 find $(srctree)/* $(RCS_FIND_IGNORE) \
2085 -name '*.[hcS]' -type f -print | sort \
2086 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
2087
2088versioncheck:
2089 find $(srctree)/* $(RCS_FIND_IGNORE) \
2090 -name '*.[hcS]' -type f -print | sort \
2091 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
2092
2093coccicheck:
2094 $(Q)$(BASH) $(srctree)/scripts/$@
2095
2096PHONY += checkstack kernelrelease kernelversion image_name
2097
2098# UML needs a little special treatment here. It wants to use the host
2099# toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
2100# else wants $(ARCH), including people doing cross-builds, which means
2101# that $(SUBARCH) doesn't work here.
2102ifeq ($(ARCH), um)
2103CHECKSTACK_ARCH := $(SUBARCH)
2104else
2105CHECKSTACK_ARCH := $(ARCH)
2106endif
2107MINSTACKSIZE ?= 100
2108checkstack:
2109 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
2110 $(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH) $(MINSTACKSIZE)
2111
2112kernelrelease:
2113 @$(filechk_kernel.release)
2114
2115kernelversion:
2116 @echo $(KERNELVERSION)
2117
2118image_name:
2119 @echo $(KBUILD_IMAGE)
2120
2121PHONY += run-command
2122run-command:
2123 $(Q)$(KBUILD_RUN_COMMAND)
2124
2125quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
2126 cmd_rmfiles = rm -rf $(rm-files)
2127
2128# read saved command lines for existing targets
2129existing-targets := $(wildcard $(sort $(targets)))
2130
2131-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
2132
2133endif # config-build
2134endif # mixed-build
2135endif # need-sub-make
2136
2137PHONY += FORCE
2138FORCE:
2139
2140# Declare the contents of the PHONY variable as phony. We keep that
2141# information in a variable so we can use it in if_changed and friends.
2142.PHONY: $(PHONY)