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 = 17
4SUBLEVEL = 0
5EXTRAVERSION =
6NAME = Baby Opossum Posse
7
8# *DOCUMENTATION*
9# To see a list of typical targets execute "make help"
10# More info can be located in ./README
11# Comments in this file are targeted only to the developer, do not
12# expect to learn how to build the kernel reading this file.
13
14ifeq ($(filter output-sync,$(.FEATURES)),)
15$(error GNU Make >= 4.0 is required. Your Make version is $(MAKE_VERSION))
16endif
17
18$(if $(filter __%, $(MAKECMDGOALS)), \
19 $(error targets prefixed with '__' are only for internal use))
20
21# That's our default target when none is given on the command line
22PHONY := __all
23__all:
24
25# We are using a recursive build, so we need to do a little thinking
26# to get the ordering right.
27#
28# Most importantly: sub-Makefiles should only ever modify files in
29# their own directory. If in some directory we have a dependency on
30# a file in another dir (which doesn't happen often, but it's often
31# unavoidable when linking the built-in.a targets which finally
32# turn into vmlinux), we will call a sub make in that other dir, and
33# after that we are sure that everything which is in that other dir
34# is now up to date.
35#
36# The only cases where we need to modify files which have global
37# effects are thus separated out and done before the recursive
38# descending is started. They are now explicitly listed as the
39# prepare rule.
40
41this-makefile := $(lastword $(MAKEFILE_LIST))
42abs_srctree := $(realpath $(dir $(this-makefile)))
43abs_output := $(CURDIR)
44
45ifneq ($(sub_make_done),1)
46
47# Do not use make's built-in rules and variables
48# (this increases performance and avoids hard-to-debug behaviour)
49MAKEFLAGS += -rR
50
51# Avoid funny character set dependencies
52unexport LC_ALL
53LC_COLLATE=C
54LC_NUMERIC=C
55export LC_COLLATE LC_NUMERIC
56
57# Avoid interference with shell env settings
58unexport GREP_OPTIONS
59
60# Beautify output
61# ---------------------------------------------------------------------------
62#
63# Most of build commands in Kbuild start with "cmd_". You can optionally define
64# "quiet_cmd_*". If defined, the short log is printed. Otherwise, no log from
65# that command is printed by default.
66#
67# e.g.)
68# quiet_cmd_depmod = DEPMOD $(MODLIB)
69# cmd_depmod = $(srctree)/scripts/depmod.sh $(DEPMOD) $(KERNELRELEASE)
70#
71# A simple variant is to prefix commands with $(Q) - that's useful
72# for commands that shall be hidden in non-verbose mode.
73#
74# $(Q)$(MAKE) $(build)=scripts/basic
75#
76# If KBUILD_VERBOSE contains 1, the whole command is echoed.
77# If KBUILD_VERBOSE contains 2, the reason for rebuilding is printed.
78#
79# To put more focus on warnings, be less verbose as default
80# Use 'make V=1' to see the full commands
81
82ifeq ("$(origin V)", "command line")
83 KBUILD_VERBOSE = $(V)
84endif
85
86quiet = quiet_
87Q = @
88
89ifneq ($(findstring 1, $(KBUILD_VERBOSE)),)
90 quiet =
91 Q =
92endif
93
94# If the user is running make -s (silent mode), suppress echoing of
95# commands
96ifneq ($(findstring s,$(firstword -$(MAKEFLAGS))),)
97quiet=silent_
98override KBUILD_VERBOSE :=
99endif
100
101export quiet Q KBUILD_VERBOSE
102
103# Call a source code checker (by default, "sparse") as part of the
104# C compilation.
105#
106# Use 'make C=1' to enable checking of only re-compiled files.
107# Use 'make C=2' to enable checking of *all* source files, regardless
108# of whether they are re-compiled or not.
109#
110# See the file "Documentation/dev-tools/sparse.rst" for more details,
111# including where to get the "sparse" utility.
112
113ifeq ("$(origin C)", "command line")
114 KBUILD_CHECKSRC = $(C)
115endif
116ifndef KBUILD_CHECKSRC
117 KBUILD_CHECKSRC = 0
118endif
119
120export KBUILD_CHECKSRC
121
122# Enable "clippy" (a linter) as part of the Rust compilation.
123#
124# Use 'make CLIPPY=1' to enable it.
125ifeq ("$(origin CLIPPY)", "command line")
126 KBUILD_CLIPPY := $(CLIPPY)
127endif
128
129export KBUILD_CLIPPY
130
131# Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
132# directory of external module to build. Setting M= takes precedence.
133ifeq ("$(origin M)", "command line")
134 KBUILD_EXTMOD := $(M)
135endif
136
137ifeq ("$(origin MO)", "command line")
138 KBUILD_EXTMOD_OUTPUT := $(MO)
139endif
140
141$(if $(word 2, $(KBUILD_EXTMOD)), \
142 $(error building multiple external modules is not supported))
143
144$(foreach x, % :, $(if $(findstring $x, $(KBUILD_EXTMOD)), \
145 $(error module directory path cannot contain '$x')))
146
147# Remove trailing slashes
148ifneq ($(filter %/, $(KBUILD_EXTMOD)),)
149KBUILD_EXTMOD := $(shell dirname $(KBUILD_EXTMOD).)
150endif
151
152export KBUILD_EXTMOD
153
154ifeq ("$(origin W)", "command line")
155 KBUILD_EXTRA_WARN := $(W)
156endif
157
158export KBUILD_EXTRA_WARN
159
160# Kbuild will save output files in the current working directory.
161# This does not need to match to the root of the kernel source tree.
162#
163# For example, you can do this:
164#
165# cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
166#
167# If you want to save output files in a different location, there are
168# two syntaxes to specify it.
169#
170# 1) O=
171# Use "make O=dir/to/store/output/files/"
172#
173# 2) Set KBUILD_OUTPUT
174# Set the environment variable KBUILD_OUTPUT to point to the output directory.
175# export KBUILD_OUTPUT=dir/to/store/output/files/; make
176#
177# The O= assignment takes precedence over the KBUILD_OUTPUT environment
178# variable.
179
180ifeq ("$(origin O)", "command line")
181 KBUILD_OUTPUT := $(O)
182endif
183
184ifdef KBUILD_EXTMOD
185 ifdef KBUILD_OUTPUT
186 objtree := $(realpath $(KBUILD_OUTPUT))
187 $(if $(objtree),,$(error specified kernel directory "$(KBUILD_OUTPUT)" does not exist))
188 else
189 objtree := $(abs_srctree)
190 endif
191 # If Make is invoked from the kernel directory (either kernel
192 # source directory or kernel build directory), external modules
193 # are built in $(KBUILD_EXTMOD) for backward compatibility,
194 # otherwise, built in the current directory.
195 output := $(or $(KBUILD_EXTMOD_OUTPUT),$(if $(filter $(CURDIR),$(objtree) $(abs_srctree)),$(KBUILD_EXTMOD)))
196 # KBUILD_EXTMOD might be a relative path. Remember its absolute path before
197 # Make changes the working directory.
198 srcroot := $(realpath $(KBUILD_EXTMOD))
199 $(if $(srcroot),,$(error specified external module directory "$(KBUILD_EXTMOD)" does not exist))
200else
201 objtree := .
202 output := $(KBUILD_OUTPUT)
203endif
204
205export objtree srcroot
206
207# Do we want to change the working directory?
208ifneq ($(output),)
209# $(realpath ...) gets empty if the path does not exist. Run 'mkdir -p' first.
210$(shell mkdir -p "$(output)")
211# $(realpath ...) resolves symlinks
212abs_output := $(realpath $(output))
213$(if $(abs_output),,$(error failed to create output directory "$(output)"))
214endif
215
216ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
217$(error source directory cannot contain spaces or colons)
218endif
219
220export sub_make_done := 1
221
222endif # sub_make_done
223
224ifeq ($(abs_output),$(CURDIR))
225# Suppress "Entering directory ..." if we are at the final work directory.
226no-print-directory := --no-print-directory
227else
228# Recursion to show "Entering directory ..."
229need-sub-make := 1
230endif
231
232ifeq ($(filter --no-print-directory, $(MAKEFLAGS)),)
233# If --no-print-directory is unset, recurse once again to set it.
234# You may end up recursing into __sub-make twice. This is needed due to the
235# behavior change in GNU Make 4.4.1.
236need-sub-make := 1
237endif
238
239ifeq ($(need-sub-make),1)
240
241PHONY += $(MAKECMDGOALS) __sub-make
242
243$(filter-out $(this-makefile), $(MAKECMDGOALS)) __all: __sub-make
244 @:
245
246# Invoke a second make in the output directory, passing relevant variables
247__sub-make:
248 $(Q)$(MAKE) $(no-print-directory) -C $(abs_output) \
249 -f $(abs_srctree)/Makefile $(MAKECMDGOALS)
250
251else # need-sub-make
252
253# We process the rest of the Makefile if this is the final invocation of make
254
255ifndef KBUILD_EXTMOD
256srcroot := $(abs_srctree)
257endif
258
259ifeq ($(srcroot),$(CURDIR))
260building_out_of_srctree :=
261else
262export building_out_of_srctree := 1
263endif
264
265ifdef KBUILD_ABS_SRCTREE
266 # Do nothing. Use the absolute path.
267else ifeq ($(srcroot),$(CURDIR))
268 # Building in the source.
269 srcroot := .
270else ifeq ($(srcroot)/,$(dir $(CURDIR)))
271 # Building in a subdirectory of the source.
272 srcroot := ..
273endif
274
275export srctree := $(if $(KBUILD_EXTMOD),$(abs_srctree),$(srcroot))
276
277ifdef building_out_of_srctree
278export VPATH := $(srcroot)
279else
280VPATH :=
281endif
282
283# To make sure we do not include .config for any of the *config targets
284# catch them early, and hand them over to scripts/kconfig/Makefile
285# It is allowed to specify more targets when calling make, including
286# mixing *config targets and build targets.
287# For example 'make oldconfig all'.
288# Detect when mixed targets is specified, and make a second invocation
289# of make so .config is not included in this case either (for *config).
290
291version_h := include/generated/uapi/linux/version.h
292
293clean-targets := %clean mrproper cleandocs
294no-dot-config-targets := $(clean-targets) \
295 cscope gtags TAGS tags help% %docs check% coccicheck \
296 $(version_h) headers headers_% archheaders archscripts \
297 %asm-generic kernelversion %src-pkg dt_binding_check \
298 outputmakefile rustavailable rustfmt rustfmtcheck
299no-sync-config-targets := $(no-dot-config-targets) %install modules_sign kernelrelease \
300 image_name
301single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.rsi %.s %/
302
303config-build :=
304mixed-build :=
305need-config := 1
306may-sync-config := 1
307single-build :=
308
309ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
310 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
311 need-config :=
312 endif
313endif
314
315ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
316 ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
317 may-sync-config :=
318 endif
319endif
320
321need-compiler := $(may-sync-config)
322
323ifneq ($(KBUILD_EXTMOD),)
324 may-sync-config :=
325endif
326
327ifeq ($(KBUILD_EXTMOD),)
328 ifneq ($(filter %config,$(MAKECMDGOALS)),)
329 config-build := 1
330 ifneq ($(words $(MAKECMDGOALS)),1)
331 mixed-build := 1
332 endif
333 endif
334endif
335
336# We cannot build single targets and the others at the same time
337ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
338 single-build := 1
339 ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
340 mixed-build := 1
341 endif
342endif
343
344# For "make -j clean all", "make -j mrproper defconfig all", etc.
345ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
346 ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
347 mixed-build := 1
348 endif
349endif
350
351# install and modules_install need also be processed one by one
352ifneq ($(filter install,$(MAKECMDGOALS)),)
353 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
354 mixed-build := 1
355 endif
356endif
357
358ifdef mixed-build
359# ===========================================================================
360# We're called with mixed targets (*config and build targets).
361# Handle them one by one.
362
363PHONY += $(MAKECMDGOALS) __build_one_by_one
364
365$(MAKECMDGOALS): __build_one_by_one
366 @:
367
368__build_one_by_one:
369 $(Q)set -e; \
370 for i in $(MAKECMDGOALS); do \
371 $(MAKE) -f $(srctree)/Makefile $$i; \
372 done
373
374else # !mixed-build
375
376include $(srctree)/scripts/Kbuild.include
377
378# Read KERNELRELEASE from include/config/kernel.release (if it exists)
379KERNELRELEASE = $(call read-file, $(objtree)/include/config/kernel.release)
380KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
381export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
382
383include $(srctree)/scripts/subarch.include
384
385# Cross compiling and selecting different set of gcc/bin-utils
386# ---------------------------------------------------------------------------
387#
388# When performing cross compilation for other architectures ARCH shall be set
389# to the target architecture. (See arch/* for the possibilities).
390# ARCH can be set during invocation of make:
391# make ARCH=arm64
392# Another way is to have ARCH set in the environment.
393# The default ARCH is the host where make is executed.
394
395# CROSS_COMPILE specify the prefix used for all executables used
396# during compilation. Only gcc and related bin-utils executables
397# are prefixed with $(CROSS_COMPILE).
398# CROSS_COMPILE can be set on the command line
399# make CROSS_COMPILE=aarch64-linux-gnu-
400# Alternatively CROSS_COMPILE can be set in the environment.
401# Default value for CROSS_COMPILE is not to prefix executables
402# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
403ARCH ?= $(SUBARCH)
404
405# Architecture as present in compile.h
406UTS_MACHINE := $(ARCH)
407SRCARCH := $(ARCH)
408
409# Additional ARCH settings for x86
410ifeq ($(ARCH),i386)
411 SRCARCH := x86
412endif
413ifeq ($(ARCH),x86_64)
414 SRCARCH := x86
415endif
416
417# Additional ARCH settings for sparc
418ifeq ($(ARCH),sparc32)
419 SRCARCH := sparc
420endif
421ifeq ($(ARCH),sparc64)
422 SRCARCH := sparc
423endif
424
425# Additional ARCH settings for parisc
426ifeq ($(ARCH),parisc64)
427 SRCARCH := parisc
428endif
429
430export cross_compiling :=
431ifneq ($(SRCARCH),$(SUBARCH))
432cross_compiling := 1
433endif
434
435KCONFIG_CONFIG ?= .config
436export KCONFIG_CONFIG
437
438# SHELL used by kbuild
439CONFIG_SHELL := sh
440
441HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
442HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
443HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
444
445ifneq ($(LLVM),)
446ifneq ($(filter %/,$(LLVM)),)
447LLVM_PREFIX := $(LLVM)
448else ifneq ($(filter -%,$(LLVM)),)
449LLVM_SUFFIX := $(LLVM)
450endif
451
452HOSTCC = $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
453HOSTCXX = $(LLVM_PREFIX)clang++$(LLVM_SUFFIX)
454else
455HOSTCC = gcc
456HOSTCXX = g++
457endif
458HOSTRUSTC = rustc
459HOSTPKG_CONFIG = pkg-config
460
461# the KERNELDOC macro needs to be exported, as scripts/Makefile.build
462# has a logic to call it
463KERNELDOC = $(srctree)/scripts/kernel-doc.py
464export KERNELDOC
465
466KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
467 -O2 -fomit-frame-pointer -std=gnu11
468KBUILD_USERCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(USERCFLAGS)
469KBUILD_USERLDFLAGS := $(USERLDFLAGS)
470
471# These flags apply to all Rust code in the tree, including the kernel and
472# host programs.
473export rust_common_flags := --edition=2021 \
474 -Zbinary_dep_depinfo=y \
475 -Astable_features \
476 -Dnon_ascii_idents \
477 -Dunsafe_op_in_unsafe_fn \
478 -Wmissing_docs \
479 -Wrust_2018_idioms \
480 -Wunreachable_pub \
481 -Wclippy::all \
482 -Wclippy::as_ptr_cast_mut \
483 -Wclippy::as_underscore \
484 -Wclippy::cast_lossless \
485 -Wclippy::ignored_unit_patterns \
486 -Wclippy::mut_mut \
487 -Wclippy::needless_bitwise_bool \
488 -Aclippy::needless_lifetimes \
489 -Wclippy::no_mangle_with_rust_abi \
490 -Wclippy::ptr_as_ptr \
491 -Wclippy::ptr_cast_constness \
492 -Wclippy::ref_as_ptr \
493 -Wclippy::undocumented_unsafe_blocks \
494 -Wclippy::unnecessary_safety_comment \
495 -Wclippy::unnecessary_safety_doc \
496 -Wrustdoc::missing_crate_level_docs \
497 -Wrustdoc::unescaped_backticks
498
499KBUILD_HOSTCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) \
500 $(HOSTCFLAGS) -I $(srctree)/scripts/include
501KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS) \
502 -I $(srctree)/scripts/include
503KBUILD_HOSTRUSTFLAGS := $(rust_common_flags) -O -Cstrip=debuginfo \
504 -Zallow-features= $(HOSTRUSTFLAGS)
505KBUILD_HOSTLDFLAGS := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
506KBUILD_HOSTLDLIBS := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
507KBUILD_PROCMACROLDFLAGS := $(or $(PROCMACROLDFLAGS),$(KBUILD_HOSTLDFLAGS))
508
509# Make variables (CC, etc...)
510CPP = $(CC) -E
511ifneq ($(LLVM),)
512CC = $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
513LD = $(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX)
514AR = $(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX)
515NM = $(LLVM_PREFIX)llvm-nm$(LLVM_SUFFIX)
516OBJCOPY = $(LLVM_PREFIX)llvm-objcopy$(LLVM_SUFFIX)
517OBJDUMP = $(LLVM_PREFIX)llvm-objdump$(LLVM_SUFFIX)
518READELF = $(LLVM_PREFIX)llvm-readelf$(LLVM_SUFFIX)
519STRIP = $(LLVM_PREFIX)llvm-strip$(LLVM_SUFFIX)
520else
521CC = $(CROSS_COMPILE)gcc
522LD = $(CROSS_COMPILE)ld
523AR = $(CROSS_COMPILE)ar
524NM = $(CROSS_COMPILE)nm
525OBJCOPY = $(CROSS_COMPILE)objcopy
526OBJDUMP = $(CROSS_COMPILE)objdump
527READELF = $(CROSS_COMPILE)readelf
528STRIP = $(CROSS_COMPILE)strip
529endif
530RUSTC = rustc
531RUSTDOC = rustdoc
532RUSTFMT = rustfmt
533CLIPPY_DRIVER = clippy-driver
534BINDGEN = bindgen
535PAHOLE = pahole
536RESOLVE_BTFIDS = $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
537LEX = flex
538YACC = bison
539AWK = awk
540INSTALLKERNEL := installkernel
541PERL = perl
542PYTHON3 = python3
543CHECK = sparse
544BASH = bash
545KGZIP = gzip
546KBZIP2 = bzip2
547KLZOP = lzop
548LZMA = lzma
549LZ4 = lz4
550XZ = xz
551ZSTD = zstd
552TAR = tar
553
554CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
555 -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
556NOSTDINC_FLAGS :=
557CFLAGS_MODULE =
558RUSTFLAGS_MODULE =
559AFLAGS_MODULE =
560LDFLAGS_MODULE =
561CFLAGS_KERNEL =
562RUSTFLAGS_KERNEL =
563AFLAGS_KERNEL =
564LDFLAGS_vmlinux =
565
566# Use USERINCLUDE when you must reference the UAPI directories only.
567USERINCLUDE := \
568 -I$(srctree)/arch/$(SRCARCH)/include/uapi \
569 -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
570 -I$(srctree)/include/uapi \
571 -I$(objtree)/include/generated/uapi \
572 -include $(srctree)/include/linux/compiler-version.h \
573 -include $(srctree)/include/linux/kconfig.h
574
575# Use LINUXINCLUDE when you must reference the include/ directory.
576# Needed to be compatible with the O= option
577LINUXINCLUDE := \
578 -I$(srctree)/arch/$(SRCARCH)/include \
579 -I$(objtree)/arch/$(SRCARCH)/include/generated \
580 -I$(srctree)/include \
581 -I$(objtree)/include \
582 $(USERINCLUDE)
583
584KBUILD_AFLAGS := -D__ASSEMBLY__ -fno-PIE
585
586KBUILD_CFLAGS :=
587KBUILD_CFLAGS += -std=gnu11
588KBUILD_CFLAGS += -fshort-wchar
589KBUILD_CFLAGS += -funsigned-char
590KBUILD_CFLAGS += -fno-common
591KBUILD_CFLAGS += -fno-PIE
592KBUILD_CFLAGS += -fno-strict-aliasing
593
594KBUILD_CPPFLAGS := -D__KERNEL__
595KBUILD_RUSTFLAGS := $(rust_common_flags) \
596 -Cpanic=abort -Cembed-bitcode=n -Clto=n \
597 -Cforce-unwind-tables=n -Ccodegen-units=1 \
598 -Csymbol-mangling-version=v0 \
599 -Crelocation-model=static \
600 -Zfunction-sections=n \
601 -Wclippy::float_arithmetic
602
603KBUILD_AFLAGS_KERNEL :=
604KBUILD_CFLAGS_KERNEL :=
605KBUILD_RUSTFLAGS_KERNEL :=
606KBUILD_AFLAGS_MODULE := -DMODULE
607KBUILD_CFLAGS_MODULE := -DMODULE
608KBUILD_RUSTFLAGS_MODULE := --cfg MODULE
609KBUILD_LDFLAGS_MODULE :=
610KBUILD_LDFLAGS :=
611CLANG_FLAGS :=
612
613ifeq ($(KBUILD_CLIPPY),1)
614 RUSTC_OR_CLIPPY_QUIET := CLIPPY
615 RUSTC_OR_CLIPPY = $(CLIPPY_DRIVER)
616else
617 RUSTC_OR_CLIPPY_QUIET := RUSTC
618 RUSTC_OR_CLIPPY = $(RUSTC)
619endif
620
621# Allows the usage of unstable features in stable compilers.
622export RUSTC_BOOTSTRAP := 1
623
624# Allows finding `.clippy.toml` in out-of-srctree builds.
625export CLIPPY_CONF_DIR := $(srctree)
626
627export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG
628export RUSTC RUSTDOC RUSTFMT RUSTC_OR_CLIPPY_QUIET RUSTC_OR_CLIPPY BINDGEN
629export HOSTRUSTC KBUILD_HOSTRUSTFLAGS
630export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
631export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
632export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD TAR
633export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS KBUILD_PROCMACROLDFLAGS LDFLAGS_MODULE
634export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS
635
636export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
637export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
638export KBUILD_RUSTFLAGS RUSTFLAGS_KERNEL RUSTFLAGS_MODULE
639export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
640export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_RUSTFLAGS_MODULE KBUILD_LDFLAGS_MODULE
641export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL KBUILD_RUSTFLAGS_KERNEL
642
643# Files to ignore in find ... statements
644
645export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o \
646 -name CVS -o -name .pc -o -name .hg -o -name .git \) \
647 -prune -o
648
649# ===========================================================================
650# Rules shared between *config targets and build targets
651
652# Basic helpers built in scripts/basic/
653PHONY += scripts_basic
654scripts_basic:
655 $(Q)$(MAKE) $(build)=scripts/basic
656
657PHONY += outputmakefile
658ifdef building_out_of_srctree
659# Before starting out-of-tree build, make sure the source tree is clean.
660# outputmakefile generates a Makefile in the output directory, if using a
661# separate output directory. This allows convenient use of make in the
662# output directory.
663# At the same time when output Makefile generated, generate .gitignore to
664# ignore whole output directory
665
666ifdef KBUILD_EXTMOD
667print_env_for_makefile = \
668 echo "export KBUILD_OUTPUT = $(objtree)"; \
669 echo "export KBUILD_EXTMOD = $(realpath $(srcroot))" ; \
670 echo "export KBUILD_EXTMOD_OUTPUT = $(CURDIR)"
671else
672print_env_for_makefile = \
673 echo "export KBUILD_OUTPUT = $(CURDIR)"
674endif
675
676quiet_cmd_makefile = GEN Makefile
677 cmd_makefile = { \
678 echo "\# Automatically generated by $(abs_srctree)/Makefile: don't edit"; \
679 $(print_env_for_makefile); \
680 echo "include $(abs_srctree)/Makefile"; \
681 } > Makefile
682
683outputmakefile:
684ifeq ($(KBUILD_EXTMOD),)
685 @if [ -f $(srctree)/.config -o \
686 -d $(srctree)/include/config -o \
687 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
688 echo >&2 "***"; \
689 echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
690 echo >&2 "*** in $(abs_srctree)";\
691 echo >&2 "***"; \
692 false; \
693 fi
694else
695 @if [ -f $(srcroot)/modules.order ]; then \
696 echo >&2 "***"; \
697 echo >&2 "*** The external module source tree is not clean."; \
698 echo >&2 "*** Please run 'make -C $(abs_srctree) M=$(realpath $(srcroot)) clean'"; \
699 echo >&2 "***"; \
700 false; \
701 fi
702endif
703 $(Q)ln -fsn $(srcroot) source
704 $(call cmd,makefile)
705 $(Q)test -e .gitignore || \
706 { echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
707endif
708
709# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
710# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
711# CC_VERSION_TEXT and RUSTC_VERSION_TEXT are referenced from Kconfig (so they
712# need export), and from include/config/auto.conf.cmd to detect the compiler
713# upgrade.
714CC_VERSION_TEXT = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1))
715RUSTC_VERSION_TEXT = $(subst $(pound),,$(shell $(RUSTC) --version 2>/dev/null))
716
717ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
718include $(srctree)/scripts/Makefile.clang
719endif
720
721# Include this also for config targets because some architectures need
722# cc-cross-prefix to determine CROSS_COMPILE.
723ifdef need-compiler
724include $(srctree)/scripts/Makefile.compiler
725endif
726
727ifdef config-build
728# ===========================================================================
729# *config targets only - make sure prerequisites are updated, and descend
730# in scripts/kconfig to make the *config target
731
732# Read arch-specific Makefile to set KBUILD_DEFCONFIG as needed.
733# KBUILD_DEFCONFIG may point out an alternative default configuration
734# used for 'make defconfig'
735include $(srctree)/arch/$(SRCARCH)/Makefile
736export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT RUSTC_VERSION_TEXT
737
738config: outputmakefile scripts_basic FORCE
739 $(Q)$(MAKE) $(build)=scripts/kconfig $@
740
741%config: outputmakefile scripts_basic FORCE
742 $(Q)$(MAKE) $(build)=scripts/kconfig $@
743
744else #!config-build
745# ===========================================================================
746# Build targets only - this includes vmlinux, arch-specific targets, clean
747# targets and others. In general all targets except *config targets.
748
749# If building an external module we do not care about the all: rule
750# but instead __all depend on modules
751PHONY += all
752ifeq ($(KBUILD_EXTMOD),)
753__all: all
754else
755__all: modules
756endif
757
758targets :=
759
760# Decide whether to build built-in, modular, or both.
761# Normally, just do built-in.
762
763KBUILD_MODULES :=
764KBUILD_BUILTIN := y
765
766# If we have only "make modules", don't compile built-in objects.
767ifeq ($(MAKECMDGOALS),modules)
768 KBUILD_BUILTIN :=
769endif
770
771# If we have "make <whatever> modules", compile modules
772# in addition to whatever we do anyway.
773# Just "make" or "make all" shall build modules as well
774
775ifneq ($(filter all modules nsdeps compile_commands.json clang-%,$(MAKECMDGOALS)),)
776 KBUILD_MODULES := y
777endif
778
779ifeq ($(MAKECMDGOALS),)
780 KBUILD_MODULES := y
781endif
782
783export KBUILD_MODULES KBUILD_BUILTIN
784
785ifdef need-config
786include $(objtree)/include/config/auto.conf
787endif
788
789ifeq ($(KBUILD_EXTMOD),)
790# Objects we will link into vmlinux / subdirs we need to visit
791core-y :=
792drivers-y :=
793libs-y := lib/
794endif # KBUILD_EXTMOD
795
796# The all: target is the default when no target is given on the
797# command line.
798# This allow a user to issue only 'make' to build a kernel including modules
799# Defaults to vmlinux, but the arch makefile usually adds further targets
800all: vmlinux
801
802CFLAGS_GCOV := -fprofile-arcs -ftest-coverage
803ifdef CONFIG_CC_IS_GCC
804CFLAGS_GCOV += -fno-tree-loop-im
805endif
806export CFLAGS_GCOV
807
808# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
809ifdef CONFIG_FUNCTION_TRACER
810 CC_FLAGS_FTRACE := -pg
811endif
812
813include $(srctree)/arch/$(SRCARCH)/Makefile
814
815ifdef need-config
816ifdef may-sync-config
817# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
818# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
819# because some architectures define CROSS_COMPILE there.
820include include/config/auto.conf.cmd
821
822$(KCONFIG_CONFIG):
823 @echo >&2 '***'
824 @echo >&2 '*** Configuration file "$@" not found!'
825 @echo >&2 '***'
826 @echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
827 @echo >&2 '*** "make menuconfig" or "make xconfig").'
828 @echo >&2 '***'
829 @/bin/false
830
831# The actual configuration files used during the build are stored in
832# include/generated/ and include/config/. Update them if .config is newer than
833# include/config/auto.conf (which mirrors .config).
834#
835# This exploits the 'multi-target pattern rule' trick.
836# The syncconfig should be executed only once to make all the targets.
837# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
838#
839# Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
840# so you cannot notice that Kconfig is waiting for the user input.
841%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h %/generated/rustc_cfg: $(KCONFIG_CONFIG)
842 $(Q)$(kecho) " SYNC $@"
843 $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
844else # !may-sync-config
845# External modules and some install targets need include/generated/autoconf.h
846# and include/config/auto.conf but do not care if they are up-to-date.
847# Use auto.conf to show the error message
848
849checked-configs := $(addprefix $(objtree)/, include/generated/autoconf.h include/generated/rustc_cfg include/config/auto.conf)
850missing-configs := $(filter-out $(wildcard $(checked-configs)), $(checked-configs))
851
852ifdef missing-configs
853PHONY += $(objtree)/include/config/auto.conf
854
855$(objtree)/include/config/auto.conf:
856 @echo >&2 '***'
857 @echo >&2 '*** ERROR: Kernel configuration is invalid. The following files are missing:'
858 @printf >&2 '*** - %s\n' $(missing-configs)
859 @echo >&2 '*** Run "make oldconfig && make prepare" on kernel source to fix it.'
860 @echo >&2 '***'
861 @/bin/false
862endif
863
864endif # may-sync-config
865endif # need-config
866
867KBUILD_CFLAGS += -fno-delete-null-pointer-checks
868
869ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
870KBUILD_CFLAGS += -O2
871KBUILD_RUSTFLAGS += -Copt-level=2
872else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
873KBUILD_CFLAGS += -Os
874KBUILD_RUSTFLAGS += -Copt-level=s
875endif
876
877# Always set `debug-assertions` and `overflow-checks` because their default
878# depends on `opt-level` and `debug-assertions`, respectively.
879KBUILD_RUSTFLAGS += -Cdebug-assertions=$(if $(CONFIG_RUST_DEBUG_ASSERTIONS),y,n)
880KBUILD_RUSTFLAGS += -Coverflow-checks=$(if $(CONFIG_RUST_OVERFLOW_CHECKS),y,n)
881
882# Tell gcc to never replace conditional load with a non-conditional one
883ifdef CONFIG_CC_IS_GCC
884# gcc-10 renamed --param=allow-store-data-races=0 to
885# -fno-allow-store-data-races.
886KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
887KBUILD_CFLAGS += $(call cc-option,-fno-allow-store-data-races)
888endif
889
890ifdef CONFIG_READABLE_ASM
891# Disable optimizations that make assembler listings hard to read.
892# reorder blocks reorders the control in the function
893# ipa clone creates specialized cloned functions
894# partial inlining inlines only parts of functions
895KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
896endif
897
898stackp-flags-y := -fno-stack-protector
899stackp-flags-$(CONFIG_STACKPROTECTOR) := -fstack-protector
900stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG) := -fstack-protector-strong
901
902KBUILD_CFLAGS += $(stackp-flags-y)
903
904KBUILD_RUSTFLAGS-$(CONFIG_WERROR) += -Dwarnings
905KBUILD_RUSTFLAGS += $(KBUILD_RUSTFLAGS-y)
906
907ifdef CONFIG_FRAME_POINTER
908KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
909KBUILD_RUSTFLAGS += -Cforce-frame-pointers=y
910else
911# Some targets (ARM with Thumb2, for example), can't be built with frame
912# pointers. For those, we don't have FUNCTION_TRACER automatically
913# select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
914# incompatible with -fomit-frame-pointer with current GCC, so we don't use
915# -fomit-frame-pointer with FUNCTION_TRACER.
916# In the Rust target specification, "frame-pointer" is set explicitly
917# to "may-omit".
918ifndef CONFIG_FUNCTION_TRACER
919KBUILD_CFLAGS += -fomit-frame-pointer
920endif
921endif
922
923# Initialize all stack variables with a 0xAA pattern.
924ifdef CONFIG_INIT_STACK_ALL_PATTERN
925KBUILD_CFLAGS += -ftrivial-auto-var-init=pattern
926endif
927
928# Initialize all stack variables with a zero value.
929ifdef CONFIG_INIT_STACK_ALL_ZERO
930KBUILD_CFLAGS += -ftrivial-auto-var-init=zero
931ifdef CONFIG_CC_HAS_AUTO_VAR_INIT_ZERO_ENABLER
932# https://github.com/llvm/llvm-project/issues/44842
933CC_AUTO_VAR_INIT_ZERO_ENABLER := -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
934export CC_AUTO_VAR_INIT_ZERO_ENABLER
935KBUILD_CFLAGS += $(CC_AUTO_VAR_INIT_ZERO_ENABLER)
936endif
937endif
938
939# Explicitly clear padding bits during variable initialization
940KBUILD_CFLAGS += $(call cc-option,-fzero-init-padding-bits=all)
941
942# While VLAs have been removed, GCC produces unreachable stack probes
943# for the randomize_kstack_offset feature. Disable it for all compilers.
944KBUILD_CFLAGS += $(call cc-option, -fno-stack-clash-protection)
945
946# Clear used registers at func exit (to reduce data lifetime and ROP gadgets).
947ifdef CONFIG_ZERO_CALL_USED_REGS
948KBUILD_CFLAGS += -fzero-call-used-regs=used-gpr
949endif
950
951ifdef CONFIG_FUNCTION_TRACER
952ifdef CONFIG_FTRACE_MCOUNT_USE_CC
953 CC_FLAGS_FTRACE += -mrecord-mcount
954 ifdef CONFIG_HAVE_NOP_MCOUNT
955 ifeq ($(call cc-option-yn, -mnop-mcount),y)
956 CC_FLAGS_FTRACE += -mnop-mcount
957 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
958 endif
959 endif
960endif
961ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
962 ifdef CONFIG_HAVE_OBJTOOL_NOP_MCOUNT
963 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
964 endif
965endif
966ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
967 ifdef CONFIG_HAVE_C_RECORDMCOUNT
968 BUILD_C_RECORDMCOUNT := y
969 export BUILD_C_RECORDMCOUNT
970 endif
971endif
972ifdef CONFIG_HAVE_FENTRY
973 # s390-linux-gnu-gcc did not support -mfentry until gcc-9.
974 ifeq ($(call cc-option-yn, -mfentry),y)
975 CC_FLAGS_FTRACE += -mfentry
976 CC_FLAGS_USING += -DCC_USING_FENTRY
977 endif
978endif
979export CC_FLAGS_FTRACE
980KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
981KBUILD_AFLAGS += $(CC_FLAGS_USING)
982endif
983
984# We trigger additional mismatches with less inlining
985ifdef CONFIG_DEBUG_SECTION_MISMATCH
986KBUILD_CFLAGS += -fno-inline-functions-called-once
987endif
988
989# `rustc`'s `-Zfunction-sections` applies to data too (as of 1.59.0).
990ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
991KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
992KBUILD_RUSTFLAGS_KERNEL += -Zfunction-sections=y
993LDFLAGS_vmlinux += --gc-sections
994endif
995
996ifdef CONFIG_SHADOW_CALL_STACK
997ifndef CONFIG_DYNAMIC_SCS
998CC_FLAGS_SCS := -fsanitize=shadow-call-stack
999KBUILD_CFLAGS += $(CC_FLAGS_SCS)
1000KBUILD_RUSTFLAGS += -Zsanitizer=shadow-call-stack
1001endif
1002export CC_FLAGS_SCS
1003endif
1004
1005ifdef CONFIG_LTO_CLANG
1006ifdef CONFIG_LTO_CLANG_THIN
1007CC_FLAGS_LTO := -flto=thin -fsplit-lto-unit
1008else
1009CC_FLAGS_LTO := -flto
1010endif
1011CC_FLAGS_LTO += -fvisibility=hidden
1012
1013# Limit inlining across translation units to reduce binary size
1014KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
1015endif
1016
1017ifdef CONFIG_LTO
1018KBUILD_CFLAGS += -fno-lto $(CC_FLAGS_LTO)
1019KBUILD_AFLAGS += -fno-lto
1020export CC_FLAGS_LTO
1021endif
1022
1023ifdef CONFIG_CFI_CLANG
1024CC_FLAGS_CFI := -fsanitize=kcfi
1025ifdef CONFIG_CFI_ICALL_NORMALIZE_INTEGERS
1026 CC_FLAGS_CFI += -fsanitize-cfi-icall-experimental-normalize-integers
1027endif
1028ifdef CONFIG_FINEIBT_BHI
1029 CC_FLAGS_CFI += -fsanitize-kcfi-arity
1030endif
1031ifdef CONFIG_RUST
1032 # Always pass -Zsanitizer-cfi-normalize-integers as CONFIG_RUST selects
1033 # CONFIG_CFI_ICALL_NORMALIZE_INTEGERS.
1034 RUSTC_FLAGS_CFI := -Zsanitizer=kcfi -Zsanitizer-cfi-normalize-integers
1035 KBUILD_RUSTFLAGS += $(RUSTC_FLAGS_CFI)
1036 export RUSTC_FLAGS_CFI
1037endif
1038KBUILD_CFLAGS += $(CC_FLAGS_CFI)
1039export CC_FLAGS_CFI
1040endif
1041
1042# Architectures can define flags to add/remove for floating-point support
1043CC_FLAGS_FPU += -D_LINUX_FPU_COMPILATION_UNIT
1044export CC_FLAGS_FPU
1045export CC_FLAGS_NO_FPU
1046
1047ifneq ($(CONFIG_FUNCTION_ALIGNMENT),0)
1048# Set the minimal function alignment. Use the newer GCC option
1049# -fmin-function-alignment if it is available, or fall back to -falign-funtions.
1050# See also CONFIG_CC_HAS_SANE_FUNCTION_ALIGNMENT.
1051ifdef CONFIG_CC_HAS_MIN_FUNCTION_ALIGNMENT
1052KBUILD_CFLAGS += -fmin-function-alignment=$(CONFIG_FUNCTION_ALIGNMENT)
1053else
1054KBUILD_CFLAGS += -falign-functions=$(CONFIG_FUNCTION_ALIGNMENT)
1055endif
1056endif
1057
1058# arch Makefile may override CC so keep this after arch Makefile is included
1059NOSTDINC_FLAGS += -nostdinc
1060
1061# To gain proper coverage for CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE,
1062# the kernel uses only C99 flexible arrays for dynamically sized trailing
1063# arrays. Enforce this for everything that may examine structure sizes and
1064# perform bounds checking.
1065KBUILD_CFLAGS += $(call cc-option, -fstrict-flex-arrays=3)
1066
1067# disable invalid "can't wrap" optimizations for signed / pointers
1068KBUILD_CFLAGS += -fno-strict-overflow
1069
1070# Make sure -fstack-check isn't enabled (like gentoo apparently did)
1071KBUILD_CFLAGS += -fno-stack-check
1072
1073# conserve stack if available
1074ifdef CONFIG_CC_IS_GCC
1075KBUILD_CFLAGS += -fconserve-stack
1076endif
1077
1078# Ensure compilers do not transform certain loops into calls to wcslen()
1079KBUILD_CFLAGS += -fno-builtin-wcslen
1080
1081# change __FILE__ to the relative path to the source directory
1082ifdef building_out_of_srctree
1083KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srcroot)/=)
1084endif
1085
1086# include additional Makefiles when needed
1087include-y := scripts/Makefile.extrawarn
1088include-$(CONFIG_DEBUG_INFO) += scripts/Makefile.debug
1089include-$(CONFIG_DEBUG_INFO_BTF)+= scripts/Makefile.btf
1090include-$(CONFIG_KASAN) += scripts/Makefile.kasan
1091include-$(CONFIG_KCSAN) += scripts/Makefile.kcsan
1092include-$(CONFIG_KMSAN) += scripts/Makefile.kmsan
1093include-$(CONFIG_UBSAN) += scripts/Makefile.ubsan
1094include-$(CONFIG_KCOV) += scripts/Makefile.kcov
1095include-$(CONFIG_RANDSTRUCT) += scripts/Makefile.randstruct
1096include-$(CONFIG_KSTACK_ERASE) += scripts/Makefile.kstack_erase
1097include-$(CONFIG_AUTOFDO_CLANG) += scripts/Makefile.autofdo
1098include-$(CONFIG_PROPELLER_CLANG) += scripts/Makefile.propeller
1099include-$(CONFIG_GCC_PLUGINS) += scripts/Makefile.gcc-plugins
1100
1101include $(addprefix $(srctree)/, $(include-y))
1102
1103# scripts/Makefile.gcc-plugins is intentionally included last.
1104# Do not add $(call cc-option,...) below this line. When you build the kernel
1105# from the clean source tree, the GCC plugins do not exist at this point.
1106
1107# Add user supplied CPPFLAGS, AFLAGS, CFLAGS and RUSTFLAGS as the last assignments
1108KBUILD_CPPFLAGS += $(KCPPFLAGS)
1109KBUILD_AFLAGS += $(KAFLAGS)
1110KBUILD_CFLAGS += $(KCFLAGS)
1111KBUILD_RUSTFLAGS += $(KRUSTFLAGS)
1112
1113KBUILD_LDFLAGS_MODULE += --build-id=sha1
1114LDFLAGS_vmlinux += --build-id=sha1
1115
1116KBUILD_LDFLAGS += -z noexecstack
1117ifeq ($(CONFIG_LD_IS_BFD),y)
1118KBUILD_LDFLAGS += $(call ld-option,--no-warn-rwx-segments)
1119endif
1120
1121ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1122LDFLAGS_vmlinux += -X
1123endif
1124
1125ifeq ($(CONFIG_RELR),y)
1126# ld.lld before 15 did not support -z pack-relative-relocs.
1127LDFLAGS_vmlinux += $(call ld-option,--pack-dyn-relocs=relr,-z pack-relative-relocs)
1128endif
1129
1130# We never want expected sections to be placed heuristically by the
1131# linker. All sections should be explicitly named in the linker script.
1132ifdef CONFIG_LD_ORPHAN_WARN
1133LDFLAGS_vmlinux += --orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL)
1134endif
1135
1136ifneq ($(CONFIG_ARCH_VMLINUX_NEEDS_RELOCS),)
1137LDFLAGS_vmlinux += --emit-relocs --discard-none
1138endif
1139
1140# Align the bit size of userspace programs with the kernel
1141KBUILD_USERCFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS))
1142KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS))
1143
1144# userspace programs are linked via the compiler, use the correct linker
1145ifdef CONFIG_CC_IS_CLANG
1146KBUILD_USERLDFLAGS += --ld-path=$(LD)
1147endif
1148
1149# make the checker run with the right architecture
1150CHECKFLAGS += --arch=$(ARCH)
1151
1152# insure the checker run with the right endianness
1153CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1154
1155# the checker needs the correct machine size
1156CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1157
1158# Default kernel image to build when no specific target is given.
1159# KBUILD_IMAGE may be overruled on the command line or
1160# set in the environment
1161# Also any assignments in arch/$(ARCH)/Makefile take precedence over
1162# this default value
1163export KBUILD_IMAGE ?= vmlinux
1164
1165#
1166# INSTALL_PATH specifies where to place the updated kernel and system map
1167# images. Default is /boot, but you can set it to other values
1168export INSTALL_PATH ?= /boot
1169
1170#
1171# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1172# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1173# an argument if needed. Otherwise it defaults to the kernel install path
1174#
1175export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1176
1177#
1178# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1179# relocations required by build roots. This is not defined in the
1180# makefile but the argument can be passed to make if needed.
1181#
1182
1183MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1184export MODLIB
1185
1186PHONY += prepare0
1187
1188ifeq ($(KBUILD_EXTMOD),)
1189
1190build-dir := .
1191clean-dirs := $(sort . Documentation \
1192 $(patsubst %/,%,$(filter %/, $(core-) \
1193 $(drivers-) $(libs-))))
1194
1195export ARCH_CORE := $(core-y)
1196export ARCH_LIB := $(filter %/, $(libs-y))
1197export ARCH_DRIVERS := $(drivers-y) $(drivers-m)
1198# Externally visible symbols (used by link-vmlinux.sh)
1199
1200KBUILD_VMLINUX_OBJS := built-in.a $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1201KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1202
1203export KBUILD_VMLINUX_LIBS
1204export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
1205
1206ifdef CONFIG_TRIM_UNUSED_KSYMS
1207# For the kernel to actually contain only the needed exported symbols,
1208# we have to build modules as well to determine what those symbols are.
1209KBUILD_MODULES := y
1210endif
1211
1212# '$(AR) mPi' needs 'T' to workaround the bug of llvm-ar <= 14
1213quiet_cmd_ar_vmlinux.a = AR $@
1214 cmd_ar_vmlinux.a = \
1215 rm -f $@; \
1216 $(AR) cDPrST $@ $(KBUILD_VMLINUX_OBJS); \
1217 $(AR) mPiT $$($(AR) t $@ | sed -n 1p) $@ $$($(AR) t $@ | grep -F -f $(srctree)/scripts/head-object-list.txt)
1218
1219targets += vmlinux.a
1220vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt FORCE
1221 $(call if_changed,ar_vmlinux.a)
1222
1223PHONY += vmlinux_o
1224vmlinux_o: vmlinux.a $(KBUILD_VMLINUX_LIBS)
1225 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o
1226
1227vmlinux.o modules.builtin.modinfo modules.builtin: vmlinux_o
1228 @:
1229
1230PHONY += vmlinux
1231# LDFLAGS_vmlinux in the top Makefile defines linker flags for the top vmlinux,
1232# not for decompressors. LDFLAGS_vmlinux in arch/*/boot/compressed/Makefile is
1233# unrelated; the decompressors just happen to have the same base name,
1234# arch/*/boot/compressed/vmlinux.
1235# Export LDFLAGS_vmlinux only to scripts/Makefile.vmlinux.
1236#
1237# _LDFLAGS_vmlinux is a workaround for the 'private export' bug:
1238# https://savannah.gnu.org/bugs/?61463
1239# For Make > 4.4, the following simple code will work:
1240# vmlinux: private export LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1241vmlinux: private _LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1242vmlinux: export LDFLAGS_vmlinux = $(_LDFLAGS_vmlinux)
1243vmlinux: vmlinux.o $(KBUILD_LDS) modpost
1244 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux
1245
1246# The actual objects are generated when descending,
1247# make sure no implicit rule kicks in
1248$(sort $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)): . ;
1249
1250ifeq ($(origin KERNELRELEASE),file)
1251filechk_kernel.release = $(srctree)/scripts/setlocalversion $(srctree)
1252else
1253filechk_kernel.release = echo $(KERNELRELEASE)
1254endif
1255
1256# Store (new) KERNELRELEASE string in include/config/kernel.release
1257include/config/kernel.release: FORCE
1258 $(call filechk,kernel.release)
1259
1260# Additional helpers built in scripts/
1261# Carefully list dependencies so we do not try to build scripts twice
1262# in parallel
1263PHONY += scripts
1264scripts: scripts_basic scripts_dtc
1265 $(Q)$(MAKE) $(build)=$(@)
1266
1267# Things we need to do before we recursively start building the kernel
1268# or the modules are listed in "prepare".
1269# A multi level approach is used. prepareN is processed before prepareN-1.
1270# archprepare is used in arch Makefiles and when processed asm symlink,
1271# version.h and scripts_basic is processed / created.
1272
1273PHONY += prepare archprepare
1274
1275archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1276 asm-generic $(version_h) include/generated/utsrelease.h \
1277 include/generated/compile.h include/generated/autoconf.h \
1278 include/generated/rustc_cfg remove-stale-files
1279
1280prepare0: archprepare
1281 $(Q)$(MAKE) $(build)=scripts/mod
1282 $(Q)$(MAKE) $(build)=. prepare
1283
1284# All the preparing..
1285prepare: prepare0
1286ifdef CONFIG_RUST
1287 +$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh
1288 $(Q)$(MAKE) $(build)=rust
1289endif
1290
1291PHONY += remove-stale-files
1292remove-stale-files:
1293 $(Q)$(srctree)/scripts/remove-stale-files
1294
1295# Support for using generic headers in asm-generic
1296asm-generic := -f $(srctree)/scripts/Makefile.asm-headers obj
1297
1298PHONY += asm-generic uapi-asm-generic
1299asm-generic: uapi-asm-generic
1300 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1301 generic=include/asm-generic
1302uapi-asm-generic:
1303 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1304 generic=include/uapi/asm-generic
1305
1306# Generate some files
1307# ---------------------------------------------------------------------------
1308
1309# KERNELRELEASE can change from a few different places, meaning version.h
1310# needs to be updated, so this check is forced on all builds
1311
1312uts_len := 64
1313define filechk_utsrelease.h
1314 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1315 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1316 exit 1; \
1317 fi; \
1318 echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1319endef
1320
1321define filechk_version.h
1322 if [ $(SUBLEVEL) -gt 255 ]; then \
1323 echo \#define LINUX_VERSION_CODE $(shell \
1324 expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1325 else \
1326 echo \#define LINUX_VERSION_CODE $(shell \
1327 expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1328 fi; \
1329 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + \
1330 ((c) > 255 ? 255 : (c)))'; \
1331 echo \#define LINUX_VERSION_MAJOR $(VERSION); \
1332 echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL); \
1333 echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1334endef
1335
1336$(version_h): private PATCHLEVEL := $(or $(PATCHLEVEL), 0)
1337$(version_h): private SUBLEVEL := $(or $(SUBLEVEL), 0)
1338$(version_h): FORCE
1339 $(call filechk,version.h)
1340
1341include/generated/utsrelease.h: include/config/kernel.release FORCE
1342 $(call filechk,utsrelease.h)
1343
1344filechk_compile.h = $(srctree)/scripts/mkcompile_h \
1345 "$(UTS_MACHINE)" "$(CONFIG_CC_VERSION_TEXT)" "$(LD)"
1346
1347include/generated/compile.h: FORCE
1348 $(call filechk,compile.h)
1349
1350PHONY += headerdep
1351headerdep:
1352 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1353 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1354
1355# ---------------------------------------------------------------------------
1356# Kernel headers
1357
1358#Default location for installed headers
1359export INSTALL_HDR_PATH = $(objtree)/usr
1360
1361quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1362 cmd_headers_install = \
1363 mkdir -p $(INSTALL_HDR_PATH); \
1364 rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1365 usr/include $(INSTALL_HDR_PATH)
1366
1367PHONY += headers_install
1368headers_install: headers
1369 $(call cmd,headers_install)
1370
1371PHONY += archheaders archscripts
1372
1373hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1374
1375PHONY += headers
1376headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders
1377ifdef HEADER_ARCH
1378 $(Q)$(MAKE) -f $(srctree)/Makefile HEADER_ARCH= SRCARCH=$(HEADER_ARCH) headers
1379else
1380 $(Q)$(MAKE) $(hdr-inst)=include/uapi
1381 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1382endif
1383
1384ifdef CONFIG_HEADERS_INSTALL
1385prepare: headers
1386endif
1387
1388PHONY += scripts_unifdef
1389scripts_unifdef: scripts_basic
1390 $(Q)$(MAKE) $(build)=scripts scripts/unifdef
1391
1392PHONY += scripts_gen_packed_field_checks
1393scripts_gen_packed_field_checks: scripts_basic
1394 $(Q)$(MAKE) $(build)=scripts scripts/gen_packed_field_checks
1395
1396# ---------------------------------------------------------------------------
1397# Install
1398
1399# Many distributions have the custom install script, /sbin/installkernel.
1400# If DKMS is installed, 'make install' will eventually recurse back
1401# to this Makefile to build and install external modules.
1402# Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
1403
1404quiet_cmd_install = INSTALL $(INSTALL_PATH)
1405 cmd_install = unset sub_make_done; $(srctree)/scripts/install.sh
1406
1407# ---------------------------------------------------------------------------
1408# vDSO install
1409
1410PHONY += vdso_install
1411vdso_install: export INSTALL_FILES = $(vdso-install-y)
1412vdso_install:
1413 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vdsoinst
1414
1415# ---------------------------------------------------------------------------
1416# Tools
1417
1418ifdef CONFIG_OBJTOOL
1419prepare: tools/objtool
1420endif
1421
1422ifdef CONFIG_BPF
1423ifdef CONFIG_DEBUG_INFO_BTF
1424prepare: tools/bpf/resolve_btfids
1425endif
1426endif
1427
1428# The tools build system is not a part of Kbuild and tends to introduce
1429# its own unique issues. If you need to integrate a new tool into Kbuild,
1430# please consider locating that tool outside the tools/ tree and using the
1431# standard Kbuild "hostprogs" syntax instead of adding a new tools/* entry
1432# here. See Documentation/kbuild/makefiles.rst for details.
1433
1434PHONY += resolve_btfids_clean
1435
1436resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1437
1438# tools/bpf/resolve_btfids directory might not exist
1439# in output directory, skip its clean in that case
1440resolve_btfids_clean:
1441ifneq ($(wildcard $(resolve_btfids_O)),)
1442 $(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1443endif
1444
1445tools/: FORCE
1446 $(Q)mkdir -p $(objtree)/tools
1447 $(Q)$(MAKE) LDFLAGS= O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1448
1449tools/%: FORCE
1450 $(Q)mkdir -p $(objtree)/tools
1451 $(Q)$(MAKE) LDFLAGS= O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1452
1453# ---------------------------------------------------------------------------
1454# Kernel selftest
1455
1456PHONY += kselftest
1457kselftest: headers
1458 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1459
1460kselftest-%: headers FORCE
1461 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1462
1463PHONY += kselftest-merge
1464kselftest-merge:
1465 $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1466 $(Q)find $(srctree)/tools/testing/selftests -name config -o -name config.$(UTS_MACHINE) | \
1467 xargs $(srctree)/scripts/kconfig/merge_config.sh -y -m $(objtree)/.config
1468 $(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1469
1470# ---------------------------------------------------------------------------
1471# Devicetree files
1472
1473ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1474dtstree := arch/$(SRCARCH)/boot/dts
1475endif
1476
1477ifneq ($(dtstree),)
1478
1479%.dtb: dtbs_prepare
1480 $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1481
1482%.dtbo: dtbs_prepare
1483 $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1484
1485PHONY += dtbs dtbs_prepare dtbs_install dtbs_check
1486dtbs: dtbs_prepare
1487 $(Q)$(MAKE) $(build)=$(dtstree) need-dtbslist=1
1488
1489# include/config/kernel.release is actually needed when installing DTBs because
1490# INSTALL_DTBS_PATH contains $(KERNELRELEASE). However, we do not want to make
1491# dtbs_install depend on it as dtbs_install may run as root.
1492dtbs_prepare: include/config/kernel.release scripts_dtc
1493
1494ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1495export CHECK_DTBS=y
1496endif
1497
1498ifneq ($(CHECK_DTBS),)
1499dtbs_prepare: dt_binding_schemas
1500endif
1501
1502dtbs_check: dtbs
1503
1504dtbs_install:
1505 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.dtbinst obj=$(dtstree)
1506
1507ifdef CONFIG_OF_EARLY_FLATTREE
1508all: dtbs
1509endif
1510
1511ifdef CONFIG_GENERIC_BUILTIN_DTB
1512vmlinux: dtbs
1513endif
1514
1515endif
1516
1517PHONY += scripts_dtc
1518scripts_dtc: scripts_basic
1519 $(Q)$(MAKE) $(build)=scripts/dtc
1520
1521ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1522export CHECK_DTBS=y
1523endif
1524
1525PHONY += dt_binding_check dt_binding_schemas
1526dt_binding_check: dt_binding_schemas scripts_dtc
1527 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1528
1529dt_binding_schemas:
1530 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1531
1532PHONY += dt_compatible_check
1533dt_compatible_check: dt_binding_schemas
1534 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1535
1536# ---------------------------------------------------------------------------
1537# Modules
1538
1539ifdef CONFIG_MODULES
1540
1541# By default, build modules as well
1542
1543all: modules
1544
1545# When we're building modules with modversions, we need to consider
1546# the built-in objects during the descend as well, in order to
1547# make sure the checksums are up to date before we record them.
1548ifdef CONFIG_MODVERSIONS
1549 KBUILD_BUILTIN := y
1550endif
1551
1552# Build modules
1553#
1554
1555# *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFO_BTF_MODULES
1556# is an exception.
1557ifdef CONFIG_DEBUG_INFO_BTF_MODULES
1558KBUILD_BUILTIN := y
1559modules: vmlinux
1560endif
1561
1562modules: modules_prepare
1563
1564# Target to prepare building external modules
1565modules_prepare: prepare
1566 $(Q)$(MAKE) $(build)=scripts scripts/module.lds
1567
1568endif # CONFIG_MODULES
1569
1570###
1571# Cleaning is done on three levels.
1572# make clean Delete most generated files
1573# Leave enough to build external modules
1574# make mrproper Delete the current configuration, and all generated files
1575# make distclean Remove editor backup files, patch leftover files and the like
1576
1577# Directories & files removed with 'make clean'
1578CLEAN_FILES += vmlinux.symvers modules-only.symvers \
1579 modules.builtin modules.builtin.modinfo modules.nsdeps \
1580 modules.builtin.ranges vmlinux.o.map vmlinux.unstripped \
1581 compile_commands.json rust/test \
1582 rust-project.json .vmlinux.objs .vmlinux.export.c \
1583 .builtin-dtbs-list .builtin-dtb.S
1584
1585# Directories & files removed with 'make mrproper'
1586MRPROPER_FILES += include/config include/generated \
1587 arch/$(SRCARCH)/include/generated .objdiff \
1588 debian snap tar-install PKGBUILD pacman \
1589 .config .config.old .version \
1590 Module.symvers \
1591 certs/signing_key.pem \
1592 certs/x509.genkey \
1593 vmlinux-gdb.py \
1594 rpmbuild \
1595 rust/libmacros.so rust/libmacros.dylib
1596
1597# clean - Delete most, but leave enough to build external modules
1598#
1599clean: private rm-files := $(CLEAN_FILES)
1600
1601PHONY += archclean vmlinuxclean
1602
1603vmlinuxclean:
1604 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1605 $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1606
1607clean: archclean vmlinuxclean resolve_btfids_clean
1608
1609# mrproper - Delete all generated files, including .config
1610#
1611mrproper: private rm-files := $(MRPROPER_FILES)
1612mrproper-dirs := $(addprefix _mrproper_,scripts)
1613
1614PHONY += $(mrproper-dirs) mrproper
1615$(mrproper-dirs):
1616 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1617
1618mrproper: clean $(mrproper-dirs)
1619 $(call cmd,rmfiles)
1620 @find . $(RCS_FIND_IGNORE) \
1621 \( -name '*.rmeta' \) \
1622 -type f -print | xargs rm -f
1623
1624# distclean
1625#
1626PHONY += distclean
1627
1628distclean: mrproper
1629 @find . $(RCS_FIND_IGNORE) \
1630 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1631 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1632 -o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1633 -o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1634 -type f -print | xargs rm -f
1635
1636
1637# Packaging of the kernel to various formats
1638# ---------------------------------------------------------------------------
1639
1640%src-pkg: FORCE
1641 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1642%pkg: include/config/kernel.release FORCE
1643 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1644
1645# Brief documentation of the typical targets used
1646# ---------------------------------------------------------------------------
1647
1648boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1649boards := $(sort $(notdir $(boards)))
1650board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1651board-dirs := $(sort $(notdir $(board-dirs:/=)))
1652
1653PHONY += help
1654help:
1655 @echo 'Cleaning targets:'
1656 @echo ' clean - Remove most generated files but keep the config and'
1657 @echo ' enough build support to build external modules'
1658 @echo ' mrproper - Remove all generated files + config + various backup files'
1659 @echo ' distclean - mrproper + remove editor backup and patch files'
1660 @echo ''
1661 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1662 @echo ''
1663 @echo 'Other generic targets:'
1664 @echo ' all - Build all targets marked with [*]'
1665 @echo '* vmlinux - Build the bare kernel'
1666 @echo '* modules - Build all modules'
1667 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1668 @echo ' vdso_install - Install unstripped vdso to INSTALL_MOD_PATH (default: /)'
1669 @echo ' dir/ - Build all files in dir and below'
1670 @echo ' dir/file.[ois] - Build specified target only'
1671 @echo ' dir/file.ll - Build the LLVM assembly file'
1672 @echo ' (requires compiler support for LLVM assembly generation)'
1673 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1674 @echo ' (requires a recent binutils and recent build (System.map))'
1675 @echo ' dir/file.ko - Build module including final link'
1676 @echo ' modules_prepare - Set up for building external modules'
1677 @echo ' tags/TAGS - Generate tags file for editors'
1678 @echo ' cscope - Generate cscope index'
1679 @echo ' gtags - Generate GNU GLOBAL index'
1680 @echo ' kernelrelease - Output the release version string (use with make -s)'
1681 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1682 @echo ' image_name - Output the image name (use with make -s)'
1683 @echo ' headers - Build ready-to-install UAPI headers in usr/include'
1684 @echo ' headers_install - Install sanitised kernel UAPI headers to INSTALL_HDR_PATH'; \
1685 echo ' (default: $(INSTALL_HDR_PATH))'; \
1686 echo ''
1687 @echo 'Static analysers:'
1688 @echo ' checkstack - Generate a list of stack hogs and consider all functions'
1689 @echo ' with a stack size larger than MINSTACKSIZE (default: 100)'
1690 @echo ' versioncheck - Sanity check on version.h usage'
1691 @echo ' includecheck - Check for duplicate included header files'
1692 @echo ' headerdep - Detect inclusion cycles in headers'
1693 @echo ' coccicheck - Check with Coccinelle'
1694 @echo ' clang-analyzer - Check with clang static analyzer'
1695 @echo ' clang-tidy - Check with clang-tidy'
1696 @echo ''
1697 @echo 'Tools:'
1698 @echo ' nsdeps - Generate missing symbol namespace dependencies'
1699 @echo ''
1700 @echo 'Kernel selftest:'
1701 @echo ' kselftest - Build and run kernel selftest'
1702 @echo ' Build, install, and boot kernel before'
1703 @echo ' running kselftest on it'
1704 @echo ' Run as root for full coverage'
1705 @echo ' kselftest-all - Build kernel selftest'
1706 @echo ' kselftest-install - Build and install kernel selftest'
1707 @echo ' kselftest-clean - Remove all generated kselftest files'
1708 @echo ' kselftest-merge - Merge all the config dependencies of'
1709 @echo ' kselftest to existing .config.'
1710 @echo ''
1711 @echo 'Rust targets:'
1712 @echo ' rustavailable - Checks whether the Rust toolchain is'
1713 @echo ' available and, if not, explains why.'
1714 @echo ' rustfmt - Reformat all the Rust code in the kernel'
1715 @echo ' rustfmtcheck - Checks if all the Rust code in the kernel'
1716 @echo ' is formatted, printing a diff otherwise.'
1717 @echo ' rustdoc - Generate Rust documentation'
1718 @echo ' (requires kernel .config)'
1719 @echo ' rusttest - Runs the Rust tests'
1720 @echo ' (requires kernel .config; downloads external repos)'
1721 @echo ' rust-analyzer - Generate rust-project.json rust-analyzer support file'
1722 @echo ' (requires kernel .config)'
1723 @echo ' dir/file.[os] - Build specified target only'
1724 @echo ' dir/file.rsi - Build macro expanded source, similar to C preprocessing.'
1725 @echo ' Run with RUSTFMT=n to skip reformatting if needed.'
1726 @echo ' The output is not intended to be compilable.'
1727 @echo ' dir/file.ll - Build the LLVM assembly file'
1728 @echo ''
1729 @$(if $(dtstree), \
1730 echo 'Devicetree:'; \
1731 echo '* dtbs - Build device tree blobs for enabled boards'; \
1732 echo ' dtbs_install - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1733 echo ' dt_binding_check - Validate device tree binding documents and examples'; \
1734 echo ' dt_binding_schemas - Build processed device tree binding schemas'; \
1735 echo ' dtbs_check - Validate device tree source files';\
1736 echo '')
1737
1738 @echo 'Userspace tools targets:'
1739 @echo ' use "make tools/help"'
1740 @echo ' or "cd tools; make help"'
1741 @echo ''
1742 @echo 'Kernel packaging:'
1743 @$(MAKE) -f $(srctree)/scripts/Makefile.package help
1744 @echo ''
1745 @echo 'Documentation targets:'
1746 @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1747 @echo ''
1748 @echo 'Architecture-specific targets ($(SRCARCH)):'
1749 @$(or $(archhelp),\
1750 echo ' No architecture-specific help defined for $(SRCARCH)')
1751 @echo ''
1752 @$(if $(boards), \
1753 $(foreach b, $(boards), \
1754 printf " %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1755 echo '')
1756 @$(if $(board-dirs), \
1757 $(foreach b, $(board-dirs), \
1758 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1759 printf " %-16s - Show all of the above\\n" help-boards; \
1760 echo '')
1761
1762 @echo ' make V=n [targets] 1: verbose build'
1763 @echo ' 2: give reason for rebuild of target'
1764 @echo ' V=1 and V=2 can be combined with V=12'
1765 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1766 @echo ' make C=1 [targets] Check re-compiled c source with $$CHECK'
1767 @echo ' (sparse by default)'
1768 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1769 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1770 @echo ' make W=n [targets] Enable extra build checks, n=1,2,3,c,e where'
1771 @echo ' 1: warnings which may be relevant and do not occur too often'
1772 @echo ' 2: warnings which occur quite often but may still be relevant'
1773 @echo ' 3: more obscure warnings, can most likely be ignored'
1774 @echo ' c: extra checks in the configuration stage (Kconfig)'
1775 @echo ' e: warnings are being treated as errors'
1776 @echo ' Multiple levels can be combined with W=12 or W=123'
1777 @$(if $(dtstree), \
1778 echo ' make CHECK_DTBS=1 [targets] Check all generated dtb files against schema'; \
1779 echo ' This can be applied both to "dtbs" and to individual "foo.dtb" targets' ; \
1780 )
1781 @echo ''
1782 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1783 @echo 'For further info see the ./README file'
1784
1785
1786help-board-dirs := $(addprefix help-,$(board-dirs))
1787
1788help-boards: $(help-board-dirs)
1789
1790boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1791
1792$(help-board-dirs): help-%:
1793 @echo 'Architecture-specific targets ($(SRCARCH) $*):'
1794 @$(if $(boards-per-dir), \
1795 $(foreach b, $(boards-per-dir), \
1796 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1797 echo '')
1798
1799
1800# Documentation targets
1801# ---------------------------------------------------------------------------
1802DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1803 linkcheckdocs dochelp refcheckdocs texinfodocs infodocs
1804PHONY += $(DOC_TARGETS)
1805$(DOC_TARGETS):
1806 $(Q)$(MAKE) $(build)=Documentation $@
1807
1808
1809# Rust targets
1810# ---------------------------------------------------------------------------
1811
1812# "Is Rust available?" target
1813PHONY += rustavailable
1814rustavailable:
1815 +$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh && echo "Rust is available!"
1816
1817# Documentation target
1818#
1819# Using the singular to avoid running afoul of `no-dot-config-targets`.
1820PHONY += rustdoc
1821rustdoc: prepare
1822 $(Q)$(MAKE) $(build)=rust $@
1823
1824# Testing target
1825PHONY += rusttest
1826rusttest: prepare
1827 $(Q)$(MAKE) $(build)=rust $@
1828
1829# Formatting targets
1830PHONY += rustfmt rustfmtcheck
1831
1832rustfmt:
1833 $(Q)find $(srctree) $(RCS_FIND_IGNORE) \
1834 -type f -a -name '*.rs' -a ! -name '*generated*' -print \
1835 | xargs $(RUSTFMT) $(rustfmt_flags)
1836
1837rustfmtcheck: rustfmt_flags = --check
1838rustfmtcheck: rustfmt
1839
1840# Misc
1841# ---------------------------------------------------------------------------
1842
1843PHONY += misc-check
1844misc-check:
1845 $(Q)$(srctree)/scripts/misc-check
1846
1847all: misc-check
1848
1849PHONY += scripts_gdb
1850scripts_gdb: prepare0
1851 $(Q)$(MAKE) $(build)=scripts/gdb
1852 $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1853
1854ifdef CONFIG_GDB_SCRIPTS
1855all: scripts_gdb
1856endif
1857
1858else # KBUILD_EXTMOD
1859
1860filechk_kernel.release = echo $(KERNELRELEASE)
1861
1862###
1863# External module support.
1864# When building external modules the kernel used as basis is considered
1865# read-only, and no consistency checks are made and the make
1866# system is not used on the basis kernel. If updates are required
1867# in the basis kernel ordinary make commands (without M=...) must be used.
1868
1869# We are always building only modules.
1870KBUILD_BUILTIN :=
1871KBUILD_MODULES := y
1872
1873build-dir := .
1874
1875clean-dirs := .
1876clean: private rm-files := Module.symvers modules.nsdeps compile_commands.json
1877
1878PHONY += prepare
1879# now expand this into a simple variable to reduce the cost of shell evaluations
1880prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT)
1881prepare:
1882 @if [ "$(CC_VERSION_TEXT)" != "$(CONFIG_CC_VERSION_TEXT)" ]; then \
1883 echo >&2 "warning: the compiler differs from the one used to build the kernel"; \
1884 echo >&2 " The kernel was built by: $(CONFIG_CC_VERSION_TEXT)"; \
1885 echo >&2 " You are using: $(CC_VERSION_TEXT)"; \
1886 fi
1887
1888PHONY += help
1889help:
1890 @echo ' Building external modules.'
1891 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1892 @echo ''
1893 @echo ' modules - default target, build the module(s)'
1894 @echo ' modules_install - install the module'
1895 @echo ' clean - remove generated files in module directory only'
1896 @echo ' rust-analyzer - generate rust-project.json rust-analyzer support file'
1897 @echo ''
1898
1899ifndef CONFIG_MODULES
1900modules modules_install: __external_modules_error
1901__external_modules_error:
1902 @echo >&2 '***'
1903 @echo >&2 '*** The present kernel disabled CONFIG_MODULES.'
1904 @echo >&2 '*** You cannot build or install external modules.'
1905 @echo >&2 '***'
1906 @false
1907endif
1908
1909endif # KBUILD_EXTMOD
1910
1911# ---------------------------------------------------------------------------
1912# Modules
1913
1914PHONY += modules modules_install modules_sign modules_prepare
1915
1916modules_install:
1917 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst \
1918 sign-only=$(if $(filter modules_install,$(MAKECMDGOALS)),,y)
1919
1920ifeq ($(CONFIG_MODULE_SIG),y)
1921# modules_sign is a subset of modules_install.
1922# 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1923modules_sign: modules_install
1924 @:
1925else
1926modules_sign:
1927 @echo >&2 '***'
1928 @echo >&2 '*** CONFIG_MODULE_SIG is disabled. You cannot sign modules.'
1929 @echo >&2 '***'
1930 @false
1931endif
1932
1933ifdef CONFIG_MODULES
1934
1935modules.order: $(build-dir)
1936 @:
1937
1938# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
1939# This is solely useful to speed up test compiles.
1940modules: modpost
1941ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1942 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1943endif
1944
1945PHONY += modules_check
1946modules_check: modules.order
1947 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1948
1949else # CONFIG_MODULES
1950
1951modules:
1952 @:
1953
1954KBUILD_MODULES :=
1955
1956endif # CONFIG_MODULES
1957
1958PHONY += modpost
1959modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \
1960 $(if $(KBUILD_MODULES), modules_check)
1961 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1962
1963# Single targets
1964# ---------------------------------------------------------------------------
1965# To build individual files in subdirectories, you can do like this:
1966#
1967# make foo/bar/baz.s
1968#
1969# The supported suffixes for single-target are listed in 'single-targets'
1970#
1971# To build only under specific subdirectories, you can do like this:
1972#
1973# make foo/bar/baz/
1974
1975ifdef single-build
1976
1977# .ko is special because modpost is needed
1978single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1979single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \
1980 $(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko)))
1981
1982$(single-ko): single_modules
1983 @:
1984$(single-no-ko): $(build-dir)
1985 @:
1986
1987# Remove modules.order when done because it is not the real one.
1988PHONY += single_modules
1989single_modules: $(single-no-ko) modules_prepare
1990 $(Q){ $(foreach m, $(single-ko), echo $(m:%.ko=%.o);) } > modules.order
1991 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1992ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1993 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1994endif
1995 $(Q)rm -f modules.order
1996
1997single-goals := $(addprefix $(build-dir)/, $(single-no-ko))
1998
1999KBUILD_MODULES := y
2000
2001endif
2002
2003prepare: outputmakefile
2004
2005# Preset locale variables to speed up the build process. Limit locale
2006# tweaks to this spot to avoid wrong language settings when running
2007# make menuconfig etc.
2008# Error messages still appears in the original language
2009PHONY += $(build-dir)
2010$(build-dir): prepare
2011 $(Q)$(MAKE) $(build)=$@ need-builtin=1 need-modorder=1 $(single-goals)
2012
2013clean-dirs := $(addprefix _clean_, $(clean-dirs))
2014PHONY += $(clean-dirs) clean
2015$(clean-dirs):
2016 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
2017
2018clean: $(clean-dirs)
2019 $(call cmd,rmfiles)
2020 @find . $(RCS_FIND_IGNORE) \
2021 \( -name '*.[aios]' -o -name '*.rsi' -o -name '*.ko' -o -name '.*.cmd' \
2022 -o -name '*.ko.*' \
2023 -o -name '*.dtb' -o -name '*.dtbo' \
2024 -o -name '*.dtb.S' -o -name '*.dtbo.S' \
2025 -o -name '*.dt.yaml' -o -name 'dtbs-list' \
2026 -o -name '*.dwo' -o -name '*.lst' \
2027 -o -name '*.su' -o -name '*.mod' \
2028 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
2029 -o -name '*.lex.c' -o -name '*.tab.[ch]' \
2030 -o -name '*.asn1.[ch]' \
2031 -o -name '*.symtypes' -o -name 'modules.order' \
2032 -o -name '*.c.[012]*.*' \
2033 -o -name '*.ll' \
2034 -o -name '*.gcno' \
2035 \) -type f -print \
2036 -o -name '.tmp_*' -print \
2037 | xargs rm -rf
2038
2039# Generate tags for editors
2040# ---------------------------------------------------------------------------
2041quiet_cmd_tags = GEN $@
2042 cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
2043
2044tags TAGS cscope gtags: FORCE
2045 $(call cmd,tags)
2046
2047# Generate rust-project.json (a file that describes the structure of non-Cargo
2048# Rust projects) for rust-analyzer (an implementation of the Language Server
2049# Protocol).
2050PHONY += rust-analyzer
2051rust-analyzer:
2052 +$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh
2053ifdef KBUILD_EXTMOD
2054# FIXME: external modules must not descend into a sub-directory of the kernel
2055 $(Q)$(MAKE) $(build)=$(objtree)/rust src=$(srctree)/rust $@
2056else
2057 $(Q)$(MAKE) $(build)=rust $@
2058endif
2059
2060# Script to generate missing namespace dependencies
2061# ---------------------------------------------------------------------------
2062
2063PHONY += nsdeps
2064nsdeps: export KBUILD_NSDEPS=1
2065nsdeps: modules
2066 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
2067
2068# Clang Tooling
2069# ---------------------------------------------------------------------------
2070
2071quiet_cmd_gen_compile_commands = GEN $@
2072 cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
2073
2074compile_commands.json: $(srctree)/scripts/clang-tools/gen_compile_commands.py \
2075 $(if $(KBUILD_EXTMOD),, vmlinux.a $(KBUILD_VMLINUX_LIBS)) \
2076 $(if $(CONFIG_MODULES), modules.order) FORCE
2077 $(call if_changed,gen_compile_commands)
2078
2079targets += compile_commands.json
2080
2081PHONY += clang-tidy clang-analyzer
2082
2083ifdef CONFIG_CC_IS_CLANG
2084quiet_cmd_clang_tools = CHECK $<
2085 cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
2086
2087clang-tidy clang-analyzer: compile_commands.json
2088 $(call cmd,clang_tools)
2089else
2090clang-tidy clang-analyzer:
2091 @echo "$@ requires CC=clang" >&2
2092 @false
2093endif
2094
2095# Scripts to check various things for consistency
2096# ---------------------------------------------------------------------------
2097
2098PHONY += includecheck versioncheck coccicheck
2099
2100includecheck:
2101 find $(srctree)/* $(RCS_FIND_IGNORE) \
2102 -name '*.[hcS]' -type f -print | sort \
2103 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
2104
2105versioncheck:
2106 find $(srctree)/* $(RCS_FIND_IGNORE) \
2107 -name '*.[hcS]' -type f -print | sort \
2108 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
2109
2110coccicheck:
2111 $(Q)$(BASH) $(srctree)/scripts/$@
2112
2113PHONY += checkstack kernelrelease kernelversion image_name
2114
2115# UML needs a little special treatment here. It wants to use the host
2116# toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
2117# else wants $(ARCH), including people doing cross-builds, which means
2118# that $(SUBARCH) doesn't work here.
2119ifeq ($(ARCH), um)
2120CHECKSTACK_ARCH := $(SUBARCH)
2121else
2122CHECKSTACK_ARCH := $(ARCH)
2123endif
2124MINSTACKSIZE ?= 100
2125checkstack:
2126 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
2127 $(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH) $(MINSTACKSIZE)
2128
2129kernelrelease:
2130 @$(filechk_kernel.release)
2131
2132kernelversion:
2133 @echo $(KERNELVERSION)
2134
2135image_name:
2136 @echo $(KBUILD_IMAGE)
2137
2138PHONY += run-command
2139run-command:
2140 $(Q)$(KBUILD_RUN_COMMAND)
2141
2142quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
2143 cmd_rmfiles = rm -rf $(rm-files)
2144
2145# read saved command lines for existing targets
2146existing-targets := $(wildcard $(sort $(targets)))
2147
2148-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
2149
2150endif # config-build
2151endif # mixed-build
2152endif # need-sub-make
2153
2154PHONY += FORCE
2155FORCE:
2156
2157# Declare the contents of the PHONY variable as phony. We keep that
2158# information in a variable so we can use it in if_changed and friends.
2159.PHONY: $(PHONY)