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 = 12
4SUBLEVEL = 0
5EXTRAVERSION = -rc2
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_objtree := $(CURDIR)
44
45ifneq ($(sub_make_done),1)
46
47# Do not use make's built-in rules and variables
48# (this increases performance and avoids hard-to-debug behaviour)
49MAKEFLAGS += -rR
50
51# Avoid funny character set dependencies
52unexport LC_ALL
53LC_COLLATE=C
54LC_NUMERIC=C
55export LC_COLLATE LC_NUMERIC
56
57# Avoid interference with shell env settings
58unexport GREP_OPTIONS
59
60# Beautify output
61# ---------------------------------------------------------------------------
62#
63# Most of build commands in Kbuild start with "cmd_". You can optionally define
64# "quiet_cmd_*". If defined, the short log is printed. Otherwise, no log from
65# that command is printed by default.
66#
67# e.g.)
68# quiet_cmd_depmod = DEPMOD $(MODLIB)
69# cmd_depmod = $(srctree)/scripts/depmod.sh $(DEPMOD) $(KERNELRELEASE)
70#
71# A simple variant is to prefix commands with $(Q) - that's useful
72# for commands that shall be hidden in non-verbose mode.
73#
74# $(Q)$(MAKE) $(build)=scripts/basic
75#
76# If KBUILD_VERBOSE contains 1, the whole command is echoed.
77# If KBUILD_VERBOSE contains 2, the reason for rebuilding is printed.
78#
79# To put more focus on warnings, be less verbose as default
80# Use 'make V=1' to see the full commands
81
82ifeq ("$(origin V)", "command line")
83 KBUILD_VERBOSE = $(V)
84endif
85
86quiet = quiet_
87Q = @
88
89ifneq ($(findstring 1, $(KBUILD_VERBOSE)),)
90 quiet =
91 Q =
92endif
93
94# If the user is running make -s (silent mode), suppress echoing of
95# commands
96ifneq ($(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 := $(M)
135endif
136
137$(if $(word 2, $(KBUILD_EXTMOD)), \
138 $(error building multiple external modules is not supported))
139
140$(foreach x, % :, $(if $(findstring $x, $(KBUILD_EXTMOD)), \
141 $(error module directory path cannot contain '$x')))
142
143# Remove trailing slashes
144ifneq ($(filter %/, $(KBUILD_EXTMOD)),)
145KBUILD_EXTMOD := $(shell dirname $(KBUILD_EXTMOD).)
146endif
147
148export KBUILD_EXTMOD
149
150# backward compatibility
151KBUILD_EXTRA_WARN ?= $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)
152
153ifeq ("$(origin W)", "command line")
154 KBUILD_EXTRA_WARN := $(W)
155endif
156
157export KBUILD_EXTRA_WARN
158
159# Kbuild will save output files in the current working directory.
160# This does not need to match to the root of the kernel source tree.
161#
162# For example, you can do this:
163#
164# cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
165#
166# If you want to save output files in a different location, there are
167# two syntaxes to specify it.
168#
169# 1) O=
170# Use "make O=dir/to/store/output/files/"
171#
172# 2) Set KBUILD_OUTPUT
173# Set the environment variable KBUILD_OUTPUT to point to the output directory.
174# export KBUILD_OUTPUT=dir/to/store/output/files/; make
175#
176# The O= assignment takes precedence over the KBUILD_OUTPUT environment
177# variable.
178
179# Do we want to change the working directory?
180ifeq ("$(origin O)", "command line")
181 KBUILD_OUTPUT := $(O)
182endif
183
184ifneq ($(KBUILD_OUTPUT),)
185# $(realpath ...) gets empty if the path does not exist. Run 'mkdir -p' first.
186$(shell mkdir -p "$(KBUILD_OUTPUT)")
187# $(realpath ...) resolves symlinks
188abs_objtree := $(realpath $(KBUILD_OUTPUT))
189$(if $(abs_objtree),,$(error failed to create output directory "$(KBUILD_OUTPUT)"))
190endif # ifneq ($(KBUILD_OUTPUT),)
191
192ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
193$(error source directory cannot contain spaces or colons)
194endif
195
196export sub_make_done := 1
197
198endif # sub_make_done
199
200ifeq ($(abs_objtree),$(CURDIR))
201# Suppress "Entering directory ..." if we are at the final work directory.
202no-print-directory := --no-print-directory
203else
204# Recursion to show "Entering directory ..."
205need-sub-make := 1
206endif
207
208ifeq ($(filter --no-print-directory, $(MAKEFLAGS)),)
209# If --no-print-directory is unset, recurse once again to set it.
210# You may end up recursing into __sub-make twice. This is needed due to the
211# behavior change in GNU Make 4.4.1.
212need-sub-make := 1
213endif
214
215ifeq ($(need-sub-make),1)
216
217PHONY += $(MAKECMDGOALS) __sub-make
218
219$(filter-out $(this-makefile), $(MAKECMDGOALS)) __all: __sub-make
220 @:
221
222# Invoke a second make in the output directory, passing relevant variables
223__sub-make:
224 $(Q)$(MAKE) $(no-print-directory) -C $(abs_objtree) \
225 -f $(abs_srctree)/Makefile $(MAKECMDGOALS)
226
227else # need-sub-make
228
229# We process the rest of the Makefile if this is the final invocation of make
230
231ifeq ($(abs_srctree),$(abs_objtree))
232 # building in the source tree
233 srctree := .
234 building_out_of_srctree :=
235else
236 ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
237 # building in a subdirectory of the source tree
238 srctree := ..
239 else
240 srctree := $(abs_srctree)
241 endif
242 building_out_of_srctree := 1
243endif
244
245ifneq ($(KBUILD_ABS_SRCTREE),)
246srctree := $(abs_srctree)
247endif
248
249objtree := .
250
251VPATH :=
252
253ifeq ($(KBUILD_EXTMOD),)
254ifdef building_out_of_srctree
255VPATH := $(srctree)
256endif
257endif
258
259export building_out_of_srctree srctree objtree VPATH
260
261# To make sure we do not include .config for any of the *config targets
262# catch them early, and hand them over to scripts/kconfig/Makefile
263# It is allowed to specify more targets when calling make, including
264# mixing *config targets and build targets.
265# For example 'make oldconfig all'.
266# Detect when mixed targets is specified, and make a second invocation
267# of make so .config is not included in this case either (for *config).
268
269version_h := include/generated/uapi/linux/version.h
270
271clean-targets := %clean mrproper cleandocs
272no-dot-config-targets := $(clean-targets) \
273 cscope gtags TAGS tags help% %docs check% coccicheck \
274 $(version_h) headers headers_% archheaders archscripts \
275 %asm-generic kernelversion %src-pkg dt_binding_check \
276 outputmakefile rustavailable rustfmt rustfmtcheck
277no-sync-config-targets := $(no-dot-config-targets) %install modules_sign kernelrelease \
278 image_name
279single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.rsi %.s %.symtypes %/
280
281config-build :=
282mixed-build :=
283need-config := 1
284may-sync-config := 1
285single-build :=
286
287ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
288 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
289 need-config :=
290 endif
291endif
292
293ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
294 ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
295 may-sync-config :=
296 endif
297endif
298
299need-compiler := $(may-sync-config)
300
301ifneq ($(KBUILD_EXTMOD),)
302 may-sync-config :=
303endif
304
305ifeq ($(KBUILD_EXTMOD),)
306 ifneq ($(filter %config,$(MAKECMDGOALS)),)
307 config-build := 1
308 ifneq ($(words $(MAKECMDGOALS)),1)
309 mixed-build := 1
310 endif
311 endif
312endif
313
314# We cannot build single targets and the others at the same time
315ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
316 single-build := 1
317 ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
318 mixed-build := 1
319 endif
320endif
321
322# For "make -j clean all", "make -j mrproper defconfig all", etc.
323ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
324 ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
325 mixed-build := 1
326 endif
327endif
328
329# install and modules_install need also be processed one by one
330ifneq ($(filter install,$(MAKECMDGOALS)),)
331 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
332 mixed-build := 1
333 endif
334endif
335
336ifdef mixed-build
337# ===========================================================================
338# We're called with mixed targets (*config and build targets).
339# Handle them one by one.
340
341PHONY += $(MAKECMDGOALS) __build_one_by_one
342
343$(MAKECMDGOALS): __build_one_by_one
344 @:
345
346__build_one_by_one:
347 $(Q)set -e; \
348 for i in $(MAKECMDGOALS); do \
349 $(MAKE) -f $(srctree)/Makefile $$i; \
350 done
351
352else # !mixed-build
353
354include $(srctree)/scripts/Kbuild.include
355
356# Read KERNELRELEASE from include/config/kernel.release (if it exists)
357KERNELRELEASE = $(call read-file, include/config/kernel.release)
358KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
359export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
360
361include $(srctree)/scripts/subarch.include
362
363# Cross compiling and selecting different set of gcc/bin-utils
364# ---------------------------------------------------------------------------
365#
366# When performing cross compilation for other architectures ARCH shall be set
367# to the target architecture. (See arch/* for the possibilities).
368# ARCH can be set during invocation of make:
369# make ARCH=arm64
370# Another way is to have ARCH set in the environment.
371# The default ARCH is the host where make is executed.
372
373# CROSS_COMPILE specify the prefix used for all executables used
374# during compilation. Only gcc and related bin-utils executables
375# are prefixed with $(CROSS_COMPILE).
376# CROSS_COMPILE can be set on the command line
377# make CROSS_COMPILE=aarch64-linux-gnu-
378# Alternatively CROSS_COMPILE can be set in the environment.
379# Default value for CROSS_COMPILE is not to prefix executables
380# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
381ARCH ?= $(SUBARCH)
382
383# Architecture as present in compile.h
384UTS_MACHINE := $(ARCH)
385SRCARCH := $(ARCH)
386
387# Additional ARCH settings for x86
388ifeq ($(ARCH),i386)
389 SRCARCH := x86
390endif
391ifeq ($(ARCH),x86_64)
392 SRCARCH := x86
393endif
394
395# Additional ARCH settings for sparc
396ifeq ($(ARCH),sparc32)
397 SRCARCH := sparc
398endif
399ifeq ($(ARCH),sparc64)
400 SRCARCH := sparc
401endif
402
403# Additional ARCH settings for parisc
404ifeq ($(ARCH),parisc64)
405 SRCARCH := parisc
406endif
407
408export cross_compiling :=
409ifneq ($(SRCARCH),$(SUBARCH))
410cross_compiling := 1
411endif
412
413KCONFIG_CONFIG ?= .config
414export KCONFIG_CONFIG
415
416# SHELL used by kbuild
417CONFIG_SHELL := sh
418
419HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
420HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
421HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
422
423ifneq ($(LLVM),)
424ifneq ($(filter %/,$(LLVM)),)
425LLVM_PREFIX := $(LLVM)
426else ifneq ($(filter -%,$(LLVM)),)
427LLVM_SUFFIX := $(LLVM)
428endif
429
430HOSTCC = $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
431HOSTCXX = $(LLVM_PREFIX)clang++$(LLVM_SUFFIX)
432else
433HOSTCC = gcc
434HOSTCXX = g++
435endif
436HOSTRUSTC = rustc
437HOSTPKG_CONFIG = pkg-config
438
439KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
440 -O2 -fomit-frame-pointer -std=gnu11
441KBUILD_USERCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(USERCFLAGS)
442KBUILD_USERLDFLAGS := $(USERLDFLAGS)
443
444# These flags apply to all Rust code in the tree, including the kernel and
445# host programs.
446export rust_common_flags := --edition=2021 \
447 -Zbinary_dep_depinfo=y \
448 -Astable_features \
449 -Dunsafe_op_in_unsafe_fn \
450 -Dnon_ascii_idents \
451 -Wrust_2018_idioms \
452 -Wunreachable_pub \
453 -Wmissing_docs \
454 -Wrustdoc::missing_crate_level_docs \
455 -Wclippy::all \
456 -Wclippy::mut_mut \
457 -Wclippy::needless_bitwise_bool \
458 -Wclippy::needless_continue \
459 -Wclippy::no_mangle_with_rust_abi \
460 -Wclippy::dbg_macro
461
462KBUILD_HOSTCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) \
463 $(HOSTCFLAGS) -I $(srctree)/scripts/include
464KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS) \
465 -I $(srctree)/scripts/include
466KBUILD_HOSTRUSTFLAGS := $(rust_common_flags) -O -Cstrip=debuginfo \
467 -Zallow-features= $(HOSTRUSTFLAGS)
468KBUILD_HOSTLDFLAGS := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
469KBUILD_HOSTLDLIBS := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
470
471# Make variables (CC, etc...)
472CPP = $(CC) -E
473ifneq ($(LLVM),)
474CC = $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
475LD = $(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX)
476AR = $(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX)
477NM = $(LLVM_PREFIX)llvm-nm$(LLVM_SUFFIX)
478OBJCOPY = $(LLVM_PREFIX)llvm-objcopy$(LLVM_SUFFIX)
479OBJDUMP = $(LLVM_PREFIX)llvm-objdump$(LLVM_SUFFIX)
480READELF = $(LLVM_PREFIX)llvm-readelf$(LLVM_SUFFIX)
481STRIP = $(LLVM_PREFIX)llvm-strip$(LLVM_SUFFIX)
482else
483CC = $(CROSS_COMPILE)gcc
484LD = $(CROSS_COMPILE)ld
485AR = $(CROSS_COMPILE)ar
486NM = $(CROSS_COMPILE)nm
487OBJCOPY = $(CROSS_COMPILE)objcopy
488OBJDUMP = $(CROSS_COMPILE)objdump
489READELF = $(CROSS_COMPILE)readelf
490STRIP = $(CROSS_COMPILE)strip
491endif
492RUSTC = rustc
493RUSTDOC = rustdoc
494RUSTFMT = rustfmt
495CLIPPY_DRIVER = clippy-driver
496BINDGEN = bindgen
497PAHOLE = pahole
498RESOLVE_BTFIDS = $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
499LEX = flex
500YACC = bison
501AWK = awk
502INSTALLKERNEL := installkernel
503PERL = perl
504PYTHON3 = python3
505CHECK = sparse
506BASH = bash
507KGZIP = gzip
508KBZIP2 = bzip2
509KLZOP = lzop
510LZMA = lzma
511LZ4 = lz4c
512XZ = xz
513ZSTD = zstd
514
515CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
516 -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
517NOSTDINC_FLAGS :=
518CFLAGS_MODULE =
519RUSTFLAGS_MODULE =
520AFLAGS_MODULE =
521LDFLAGS_MODULE =
522CFLAGS_KERNEL =
523RUSTFLAGS_KERNEL =
524AFLAGS_KERNEL =
525LDFLAGS_vmlinux =
526
527# Use USERINCLUDE when you must reference the UAPI directories only.
528USERINCLUDE := \
529 -I$(srctree)/arch/$(SRCARCH)/include/uapi \
530 -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
531 -I$(srctree)/include/uapi \
532 -I$(objtree)/include/generated/uapi \
533 -include $(srctree)/include/linux/compiler-version.h \
534 -include $(srctree)/include/linux/kconfig.h
535
536# Use LINUXINCLUDE when you must reference the include/ directory.
537# Needed to be compatible with the O= option
538LINUXINCLUDE := \
539 -I$(srctree)/arch/$(SRCARCH)/include \
540 -I$(objtree)/arch/$(SRCARCH)/include/generated \
541 $(if $(building_out_of_srctree),-I$(srctree)/include) \
542 -I$(objtree)/include \
543 $(USERINCLUDE)
544
545KBUILD_AFLAGS := -D__ASSEMBLY__ -fno-PIE
546
547KBUILD_CFLAGS :=
548KBUILD_CFLAGS += -std=gnu11
549KBUILD_CFLAGS += -fshort-wchar
550KBUILD_CFLAGS += -funsigned-char
551KBUILD_CFLAGS += -fno-common
552KBUILD_CFLAGS += -fno-PIE
553KBUILD_CFLAGS += -fno-strict-aliasing
554
555KBUILD_CPPFLAGS := -D__KERNEL__
556KBUILD_RUSTFLAGS := $(rust_common_flags) \
557 -Cpanic=abort -Cembed-bitcode=n -Clto=n \
558 -Cforce-unwind-tables=n -Ccodegen-units=1 \
559 -Csymbol-mangling-version=v0 \
560 -Crelocation-model=static \
561 -Zfunction-sections=n \
562 -Wclippy::float_arithmetic
563
564KBUILD_AFLAGS_KERNEL :=
565KBUILD_CFLAGS_KERNEL :=
566KBUILD_RUSTFLAGS_KERNEL :=
567KBUILD_AFLAGS_MODULE := -DMODULE
568KBUILD_CFLAGS_MODULE := -DMODULE
569KBUILD_RUSTFLAGS_MODULE := --cfg MODULE
570KBUILD_LDFLAGS_MODULE :=
571KBUILD_LDFLAGS :=
572CLANG_FLAGS :=
573
574ifeq ($(KBUILD_CLIPPY),1)
575 RUSTC_OR_CLIPPY_QUIET := CLIPPY
576 RUSTC_OR_CLIPPY = $(CLIPPY_DRIVER)
577else
578 RUSTC_OR_CLIPPY_QUIET := RUSTC
579 RUSTC_OR_CLIPPY = $(RUSTC)
580endif
581
582# Allows the usage of unstable features in stable compilers.
583export RUSTC_BOOTSTRAP := 1
584
585export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG
586export RUSTC RUSTDOC RUSTFMT RUSTC_OR_CLIPPY_QUIET RUSTC_OR_CLIPPY BINDGEN
587export HOSTRUSTC KBUILD_HOSTRUSTFLAGS
588export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
589export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
590export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
591export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
592export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS
593
594export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
595export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
596export KBUILD_RUSTFLAGS RUSTFLAGS_KERNEL RUSTFLAGS_MODULE
597export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
598export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_RUSTFLAGS_MODULE KBUILD_LDFLAGS_MODULE
599export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL KBUILD_RUSTFLAGS_KERNEL
600
601# Files to ignore in find ... statements
602
603export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o \
604 -name CVS -o -name .pc -o -name .hg -o -name .git \) \
605 -prune -o
606
607# ===========================================================================
608# Rules shared between *config targets and build targets
609
610# Basic helpers built in scripts/basic/
611PHONY += scripts_basic
612scripts_basic:
613 $(Q)$(MAKE) $(build)=scripts/basic
614
615PHONY += outputmakefile
616ifdef building_out_of_srctree
617# Before starting out-of-tree build, make sure the source tree is clean.
618# outputmakefile generates a Makefile in the output directory, if using a
619# separate output directory. This allows convenient use of make in the
620# output directory.
621# At the same time when output Makefile generated, generate .gitignore to
622# ignore whole output directory
623
624quiet_cmd_makefile = GEN Makefile
625 cmd_makefile = { \
626 echo "\# Automatically generated by $(srctree)/Makefile: don't edit"; \
627 echo "include $(srctree)/Makefile"; \
628 } > Makefile
629
630outputmakefile:
631 @if [ -f $(srctree)/.config -o \
632 -d $(srctree)/include/config -o \
633 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
634 echo >&2 "***"; \
635 echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
636 echo >&2 "*** in $(abs_srctree)";\
637 echo >&2 "***"; \
638 false; \
639 fi
640 $(Q)ln -fsn $(srctree) source
641 $(call cmd,makefile)
642 $(Q)test -e .gitignore || \
643 { echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
644endif
645
646# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
647# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
648# CC_VERSION_TEXT and RUSTC_VERSION_TEXT are referenced from Kconfig (so they
649# need export), and from include/config/auto.conf.cmd to detect the compiler
650# upgrade.
651CC_VERSION_TEXT = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1))
652RUSTC_VERSION_TEXT = $(subst $(pound),,$(shell $(RUSTC) --version 2>/dev/null))
653
654ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
655include $(srctree)/scripts/Makefile.clang
656endif
657
658# Include this also for config targets because some architectures need
659# cc-cross-prefix to determine CROSS_COMPILE.
660ifdef need-compiler
661include $(srctree)/scripts/Makefile.compiler
662endif
663
664ifdef config-build
665# ===========================================================================
666# *config targets only - make sure prerequisites are updated, and descend
667# in scripts/kconfig to make the *config target
668
669# Read arch-specific Makefile to set KBUILD_DEFCONFIG as needed.
670# KBUILD_DEFCONFIG may point out an alternative default configuration
671# used for 'make defconfig'
672include $(srctree)/arch/$(SRCARCH)/Makefile
673export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT RUSTC_VERSION_TEXT
674
675config: outputmakefile scripts_basic FORCE
676 $(Q)$(MAKE) $(build)=scripts/kconfig $@
677
678%config: outputmakefile scripts_basic FORCE
679 $(Q)$(MAKE) $(build)=scripts/kconfig $@
680
681else #!config-build
682# ===========================================================================
683# Build targets only - this includes vmlinux, arch-specific targets, clean
684# targets and others. In general all targets except *config targets.
685
686# If building an external module we do not care about the all: rule
687# but instead __all depend on modules
688PHONY += all
689ifeq ($(KBUILD_EXTMOD),)
690__all: all
691else
692__all: modules
693endif
694
695targets :=
696
697# Decide whether to build built-in, modular, or both.
698# Normally, just do built-in.
699
700KBUILD_MODULES :=
701KBUILD_BUILTIN := 1
702
703# If we have only "make modules", don't compile built-in objects.
704ifeq ($(MAKECMDGOALS),modules)
705 KBUILD_BUILTIN :=
706endif
707
708# If we have "make <whatever> modules", compile modules
709# in addition to whatever we do anyway.
710# Just "make" or "make all" shall build modules as well
711
712ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
713 KBUILD_MODULES := 1
714endif
715
716ifeq ($(MAKECMDGOALS),)
717 KBUILD_MODULES := 1
718endif
719
720export KBUILD_MODULES KBUILD_BUILTIN
721
722ifdef need-config
723include include/config/auto.conf
724endif
725
726ifeq ($(KBUILD_EXTMOD),)
727# Objects we will link into vmlinux / subdirs we need to visit
728core-y :=
729drivers-y :=
730libs-y := lib/
731endif # KBUILD_EXTMOD
732
733# The all: target is the default when no target is given on the
734# command line.
735# This allow a user to issue only 'make' to build a kernel including modules
736# Defaults to vmlinux, but the arch makefile usually adds further targets
737all: vmlinux
738
739CFLAGS_GCOV := -fprofile-arcs -ftest-coverage
740ifdef CONFIG_CC_IS_GCC
741CFLAGS_GCOV += -fno-tree-loop-im
742endif
743export CFLAGS_GCOV
744
745# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
746ifdef CONFIG_FUNCTION_TRACER
747 CC_FLAGS_FTRACE := -pg
748endif
749
750include $(srctree)/arch/$(SRCARCH)/Makefile
751
752ifdef need-config
753ifdef may-sync-config
754# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
755# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
756# because some architectures define CROSS_COMPILE there.
757include include/config/auto.conf.cmd
758
759$(KCONFIG_CONFIG):
760 @echo >&2 '***'
761 @echo >&2 '*** Configuration file "$@" not found!'
762 @echo >&2 '***'
763 @echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
764 @echo >&2 '*** "make menuconfig" or "make xconfig").'
765 @echo >&2 '***'
766 @/bin/false
767
768# The actual configuration files used during the build are stored in
769# include/generated/ and include/config/. Update them if .config is newer than
770# include/config/auto.conf (which mirrors .config).
771#
772# This exploits the 'multi-target pattern rule' trick.
773# The syncconfig should be executed only once to make all the targets.
774# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
775#
776# Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
777# so you cannot notice that Kconfig is waiting for the user input.
778%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h %/generated/rustc_cfg: $(KCONFIG_CONFIG)
779 $(Q)$(kecho) " SYNC $@"
780 $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
781else # !may-sync-config
782# External modules and some install targets need include/generated/autoconf.h
783# and include/config/auto.conf but do not care if they are up-to-date.
784# Use auto.conf to trigger the test
785PHONY += include/config/auto.conf
786
787include/config/auto.conf:
788 @test -e include/generated/autoconf.h -a -e $@ || ( \
789 echo >&2; \
790 echo >&2 " ERROR: Kernel configuration is invalid."; \
791 echo >&2 " include/generated/autoconf.h or $@ are missing.";\
792 echo >&2 " Run 'make oldconfig && make prepare' on kernel src to fix it."; \
793 echo >&2 ; \
794 /bin/false)
795
796endif # may-sync-config
797endif # need-config
798
799KBUILD_CFLAGS += -fno-delete-null-pointer-checks
800
801ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
802KBUILD_CFLAGS += -O2
803KBUILD_RUSTFLAGS += -Copt-level=2
804else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
805KBUILD_CFLAGS += -Os
806KBUILD_RUSTFLAGS += -Copt-level=s
807endif
808
809# Always set `debug-assertions` and `overflow-checks` because their default
810# depends on `opt-level` and `debug-assertions`, respectively.
811KBUILD_RUSTFLAGS += -Cdebug-assertions=$(if $(CONFIG_RUST_DEBUG_ASSERTIONS),y,n)
812KBUILD_RUSTFLAGS += -Coverflow-checks=$(if $(CONFIG_RUST_OVERFLOW_CHECKS),y,n)
813
814# Tell gcc to never replace conditional load with a non-conditional one
815ifdef CONFIG_CC_IS_GCC
816# gcc-10 renamed --param=allow-store-data-races=0 to
817# -fno-allow-store-data-races.
818KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
819KBUILD_CFLAGS += $(call cc-option,-fno-allow-store-data-races)
820endif
821
822ifdef CONFIG_READABLE_ASM
823# Disable optimizations that make assembler listings hard to read.
824# reorder blocks reorders the control in the function
825# ipa clone creates specialized cloned functions
826# partial inlining inlines only parts of functions
827KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
828endif
829
830stackp-flags-y := -fno-stack-protector
831stackp-flags-$(CONFIG_STACKPROTECTOR) := -fstack-protector
832stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG) := -fstack-protector-strong
833
834KBUILD_CFLAGS += $(stackp-flags-y)
835
836KBUILD_RUSTFLAGS-$(CONFIG_WERROR) += -Dwarnings
837KBUILD_RUSTFLAGS += $(KBUILD_RUSTFLAGS-y)
838
839ifdef CONFIG_FRAME_POINTER
840KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
841KBUILD_RUSTFLAGS += -Cforce-frame-pointers=y
842else
843# Some targets (ARM with Thumb2, for example), can't be built with frame
844# pointers. For those, we don't have FUNCTION_TRACER automatically
845# select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
846# incompatible with -fomit-frame-pointer with current GCC, so we don't use
847# -fomit-frame-pointer with FUNCTION_TRACER.
848# In the Rust target specification, "frame-pointer" is set explicitly
849# to "may-omit".
850ifndef CONFIG_FUNCTION_TRACER
851KBUILD_CFLAGS += -fomit-frame-pointer
852endif
853endif
854
855# Initialize all stack variables with a 0xAA pattern.
856ifdef CONFIG_INIT_STACK_ALL_PATTERN
857KBUILD_CFLAGS += -ftrivial-auto-var-init=pattern
858endif
859
860# Initialize all stack variables with a zero value.
861ifdef CONFIG_INIT_STACK_ALL_ZERO
862KBUILD_CFLAGS += -ftrivial-auto-var-init=zero
863ifdef CONFIG_CC_HAS_AUTO_VAR_INIT_ZERO_ENABLER
864# https://github.com/llvm/llvm-project/issues/44842
865CC_AUTO_VAR_INIT_ZERO_ENABLER := -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
866export CC_AUTO_VAR_INIT_ZERO_ENABLER
867KBUILD_CFLAGS += $(CC_AUTO_VAR_INIT_ZERO_ENABLER)
868endif
869endif
870
871# While VLAs have been removed, GCC produces unreachable stack probes
872# for the randomize_kstack_offset feature. Disable it for all compilers.
873KBUILD_CFLAGS += $(call cc-option, -fno-stack-clash-protection)
874
875# Clear used registers at func exit (to reduce data lifetime and ROP gadgets).
876ifdef CONFIG_ZERO_CALL_USED_REGS
877KBUILD_CFLAGS += -fzero-call-used-regs=used-gpr
878endif
879
880ifdef CONFIG_FUNCTION_TRACER
881ifdef CONFIG_FTRACE_MCOUNT_USE_CC
882 CC_FLAGS_FTRACE += -mrecord-mcount
883 ifdef CONFIG_HAVE_NOP_MCOUNT
884 ifeq ($(call cc-option-yn, -mnop-mcount),y)
885 CC_FLAGS_FTRACE += -mnop-mcount
886 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
887 endif
888 endif
889endif
890ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
891 ifdef CONFIG_HAVE_OBJTOOL_NOP_MCOUNT
892 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
893 endif
894endif
895ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
896 ifdef CONFIG_HAVE_C_RECORDMCOUNT
897 BUILD_C_RECORDMCOUNT := y
898 export BUILD_C_RECORDMCOUNT
899 endif
900endif
901ifdef CONFIG_HAVE_FENTRY
902 # s390-linux-gnu-gcc did not support -mfentry until gcc-9.
903 ifeq ($(call cc-option-yn, -mfentry),y)
904 CC_FLAGS_FTRACE += -mfentry
905 CC_FLAGS_USING += -DCC_USING_FENTRY
906 endif
907endif
908export CC_FLAGS_FTRACE
909KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
910KBUILD_AFLAGS += $(CC_FLAGS_USING)
911endif
912
913# We trigger additional mismatches with less inlining
914ifdef CONFIG_DEBUG_SECTION_MISMATCH
915KBUILD_CFLAGS += -fno-inline-functions-called-once
916endif
917
918# `rustc`'s `-Zfunction-sections` applies to data too (as of 1.59.0).
919ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
920KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
921KBUILD_RUSTFLAGS_KERNEL += -Zfunction-sections=y
922LDFLAGS_vmlinux += --gc-sections
923endif
924
925ifdef CONFIG_SHADOW_CALL_STACK
926ifndef CONFIG_DYNAMIC_SCS
927CC_FLAGS_SCS := -fsanitize=shadow-call-stack
928KBUILD_CFLAGS += $(CC_FLAGS_SCS)
929KBUILD_RUSTFLAGS += -Zsanitizer=shadow-call-stack
930endif
931export CC_FLAGS_SCS
932endif
933
934ifdef CONFIG_LTO_CLANG
935ifdef CONFIG_LTO_CLANG_THIN
936CC_FLAGS_LTO := -flto=thin -fsplit-lto-unit
937else
938CC_FLAGS_LTO := -flto
939endif
940CC_FLAGS_LTO += -fvisibility=hidden
941
942# Limit inlining across translation units to reduce binary size
943KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
944endif
945
946ifdef CONFIG_LTO
947KBUILD_CFLAGS += -fno-lto $(CC_FLAGS_LTO)
948KBUILD_AFLAGS += -fno-lto
949export CC_FLAGS_LTO
950endif
951
952ifdef CONFIG_CFI_CLANG
953CC_FLAGS_CFI := -fsanitize=kcfi
954ifdef CONFIG_CFI_ICALL_NORMALIZE_INTEGERS
955 CC_FLAGS_CFI += -fsanitize-cfi-icall-experimental-normalize-integers
956endif
957ifdef CONFIG_RUST
958 # Always pass -Zsanitizer-cfi-normalize-integers as CONFIG_RUST selects
959 # CONFIG_CFI_ICALL_NORMALIZE_INTEGERS.
960 RUSTC_FLAGS_CFI := -Zsanitizer=kcfi -Zsanitizer-cfi-normalize-integers
961 KBUILD_RUSTFLAGS += $(RUSTC_FLAGS_CFI)
962 export RUSTC_FLAGS_CFI
963endif
964KBUILD_CFLAGS += $(CC_FLAGS_CFI)
965export CC_FLAGS_CFI
966endif
967
968# Architectures can define flags to add/remove for floating-point support
969CC_FLAGS_FPU += -D_LINUX_FPU_COMPILATION_UNIT
970export CC_FLAGS_FPU
971export CC_FLAGS_NO_FPU
972
973ifneq ($(CONFIG_FUNCTION_ALIGNMENT),0)
974# Set the minimal function alignment. Use the newer GCC option
975# -fmin-function-alignment if it is available, or fall back to -falign-funtions.
976# See also CONFIG_CC_HAS_SANE_FUNCTION_ALIGNMENT.
977ifdef CONFIG_CC_HAS_MIN_FUNCTION_ALIGNMENT
978KBUILD_CFLAGS += -fmin-function-alignment=$(CONFIG_FUNCTION_ALIGNMENT)
979else
980KBUILD_CFLAGS += -falign-functions=$(CONFIG_FUNCTION_ALIGNMENT)
981endif
982endif
983
984# arch Makefile may override CC so keep this after arch Makefile is included
985NOSTDINC_FLAGS += -nostdinc
986
987# To gain proper coverage for CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE,
988# the kernel uses only C99 flexible arrays for dynamically sized trailing
989# arrays. Enforce this for everything that may examine structure sizes and
990# perform bounds checking.
991KBUILD_CFLAGS += $(call cc-option, -fstrict-flex-arrays=3)
992
993#Currently, disable -Wstringop-overflow for GCC 11, globally.
994KBUILD_CFLAGS-$(CONFIG_CC_NO_STRINGOP_OVERFLOW) += $(call cc-option, -Wno-stringop-overflow)
995KBUILD_CFLAGS-$(CONFIG_CC_STRINGOP_OVERFLOW) += $(call cc-option, -Wstringop-overflow)
996
997# disable invalid "can't wrap" optimizations for signed / pointers
998KBUILD_CFLAGS += -fno-strict-overflow
999
1000# Make sure -fstack-check isn't enabled (like gentoo apparently did)
1001KBUILD_CFLAGS += -fno-stack-check
1002
1003# conserve stack if available
1004ifdef CONFIG_CC_IS_GCC
1005KBUILD_CFLAGS += -fconserve-stack
1006endif
1007
1008# change __FILE__ to the relative path from the srctree
1009KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
1010
1011# include additional Makefiles when needed
1012include-y := scripts/Makefile.extrawarn
1013include-$(CONFIG_DEBUG_INFO) += scripts/Makefile.debug
1014include-$(CONFIG_DEBUG_INFO_BTF)+= scripts/Makefile.btf
1015include-$(CONFIG_KASAN) += scripts/Makefile.kasan
1016include-$(CONFIG_KCSAN) += scripts/Makefile.kcsan
1017include-$(CONFIG_KMSAN) += scripts/Makefile.kmsan
1018include-$(CONFIG_UBSAN) += scripts/Makefile.ubsan
1019include-$(CONFIG_KCOV) += scripts/Makefile.kcov
1020include-$(CONFIG_RANDSTRUCT) += scripts/Makefile.randstruct
1021include-$(CONFIG_GCC_PLUGINS) += scripts/Makefile.gcc-plugins
1022
1023include $(addprefix $(srctree)/, $(include-y))
1024
1025# scripts/Makefile.gcc-plugins is intentionally included last.
1026# Do not add $(call cc-option,...) below this line. When you build the kernel
1027# from the clean source tree, the GCC plugins do not exist at this point.
1028
1029# Add user supplied CPPFLAGS, AFLAGS, CFLAGS and RUSTFLAGS as the last assignments
1030KBUILD_CPPFLAGS += $(KCPPFLAGS)
1031KBUILD_AFLAGS += $(KAFLAGS)
1032KBUILD_CFLAGS += $(KCFLAGS)
1033KBUILD_RUSTFLAGS += $(KRUSTFLAGS)
1034
1035KBUILD_LDFLAGS_MODULE += --build-id=sha1
1036LDFLAGS_vmlinux += --build-id=sha1
1037
1038KBUILD_LDFLAGS += -z noexecstack
1039ifeq ($(CONFIG_LD_IS_BFD),y)
1040KBUILD_LDFLAGS += $(call ld-option,--no-warn-rwx-segments)
1041endif
1042
1043ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1044LDFLAGS_vmlinux += -X
1045endif
1046
1047ifeq ($(CONFIG_RELR),y)
1048# ld.lld before 15 did not support -z pack-relative-relocs.
1049LDFLAGS_vmlinux += $(call ld-option,--pack-dyn-relocs=relr,-z pack-relative-relocs)
1050endif
1051
1052# We never want expected sections to be placed heuristically by the
1053# linker. All sections should be explicitly named in the linker script.
1054ifdef CONFIG_LD_ORPHAN_WARN
1055LDFLAGS_vmlinux += --orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL)
1056endif
1057
1058# Align the bit size of userspace programs with the kernel
1059KBUILD_USERCFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1060KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1061
1062# make the checker run with the right architecture
1063CHECKFLAGS += --arch=$(ARCH)
1064
1065# insure the checker run with the right endianness
1066CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1067
1068# the checker needs the correct machine size
1069CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1070
1071# Default kernel image to build when no specific target is given.
1072# KBUILD_IMAGE may be overruled on the command line or
1073# set in the environment
1074# Also any assignments in arch/$(ARCH)/Makefile take precedence over
1075# this default value
1076export KBUILD_IMAGE ?= vmlinux
1077
1078#
1079# INSTALL_PATH specifies where to place the updated kernel and system map
1080# images. Default is /boot, but you can set it to other values
1081export INSTALL_PATH ?= /boot
1082
1083#
1084# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1085# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1086# an argument if needed. Otherwise it defaults to the kernel install path
1087#
1088export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1089
1090#
1091# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1092# relocations required by build roots. This is not defined in the
1093# makefile but the argument can be passed to make if needed.
1094#
1095
1096MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1097export MODLIB
1098
1099PHONY += prepare0
1100
1101export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
1102export MODORDER := $(extmod_prefix)modules.order
1103export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
1104
1105ifeq ($(KBUILD_EXTMOD),)
1106
1107build-dir := .
1108clean-dirs := $(sort . Documentation \
1109 $(patsubst %/,%,$(filter %/, $(core-) \
1110 $(drivers-) $(libs-))))
1111
1112export ARCH_CORE := $(core-y)
1113export ARCH_LIB := $(filter %/, $(libs-y))
1114export ARCH_DRIVERS := $(drivers-y) $(drivers-m)
1115# Externally visible symbols (used by link-vmlinux.sh)
1116
1117KBUILD_VMLINUX_OBJS := ./built-in.a
1118ifdef CONFIG_MODULES
1119KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1120KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1121else
1122KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1123endif
1124
1125export KBUILD_VMLINUX_LIBS
1126export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
1127
1128ifdef CONFIG_TRIM_UNUSED_KSYMS
1129# For the kernel to actually contain only the needed exported symbols,
1130# we have to build modules as well to determine what those symbols are.
1131KBUILD_MODULES := 1
1132endif
1133
1134# '$(AR) mPi' needs 'T' to workaround the bug of llvm-ar <= 14
1135quiet_cmd_ar_vmlinux.a = AR $@
1136 cmd_ar_vmlinux.a = \
1137 rm -f $@; \
1138 $(AR) cDPrST $@ $(KBUILD_VMLINUX_OBJS); \
1139 $(AR) mPiT $$($(AR) t $@ | sed -n 1p) $@ $$($(AR) t $@ | grep -F -f $(srctree)/scripts/head-object-list.txt)
1140
1141targets += vmlinux.a
1142vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt FORCE
1143 $(call if_changed,ar_vmlinux.a)
1144
1145PHONY += vmlinux_o
1146vmlinux_o: vmlinux.a $(KBUILD_VMLINUX_LIBS)
1147 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o
1148
1149vmlinux.o modules.builtin.modinfo modules.builtin: vmlinux_o
1150 @:
1151
1152PHONY += vmlinux
1153# LDFLAGS_vmlinux in the top Makefile defines linker flags for the top vmlinux,
1154# not for decompressors. LDFLAGS_vmlinux in arch/*/boot/compressed/Makefile is
1155# unrelated; the decompressors just happen to have the same base name,
1156# arch/*/boot/compressed/vmlinux.
1157# Export LDFLAGS_vmlinux only to scripts/Makefile.vmlinux.
1158#
1159# _LDFLAGS_vmlinux is a workaround for the 'private export' bug:
1160# https://savannah.gnu.org/bugs/?61463
1161# For Make > 4.4, the following simple code will work:
1162# vmlinux: private export LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1163vmlinux: private _LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1164vmlinux: export LDFLAGS_vmlinux = $(_LDFLAGS_vmlinux)
1165vmlinux: vmlinux.o $(KBUILD_LDS) modpost
1166 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux
1167
1168# The actual objects are generated when descending,
1169# make sure no implicit rule kicks in
1170$(sort $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)): . ;
1171
1172ifeq ($(origin KERNELRELEASE),file)
1173filechk_kernel.release = $(srctree)/scripts/setlocalversion $(srctree)
1174else
1175filechk_kernel.release = echo $(KERNELRELEASE)
1176endif
1177
1178# Store (new) KERNELRELEASE string in include/config/kernel.release
1179include/config/kernel.release: FORCE
1180 $(call filechk,kernel.release)
1181
1182# Additional helpers built in scripts/
1183# Carefully list dependencies so we do not try to build scripts twice
1184# in parallel
1185PHONY += scripts
1186scripts: scripts_basic scripts_dtc
1187 $(Q)$(MAKE) $(build)=$(@)
1188
1189# Things we need to do before we recursively start building the kernel
1190# or the modules are listed in "prepare".
1191# A multi level approach is used. prepareN is processed before prepareN-1.
1192# archprepare is used in arch Makefiles and when processed asm symlink,
1193# version.h and scripts_basic is processed / created.
1194
1195PHONY += prepare archprepare
1196
1197archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1198 asm-generic $(version_h) include/generated/utsrelease.h \
1199 include/generated/compile.h include/generated/autoconf.h remove-stale-files
1200
1201prepare0: archprepare
1202 $(Q)$(MAKE) $(build)=scripts/mod
1203 $(Q)$(MAKE) $(build)=. prepare
1204
1205# All the preparing..
1206prepare: prepare0
1207ifdef CONFIG_RUST
1208 +$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh
1209 $(Q)$(MAKE) $(build)=rust
1210endif
1211
1212PHONY += remove-stale-files
1213remove-stale-files:
1214 $(Q)$(srctree)/scripts/remove-stale-files
1215
1216# Support for using generic headers in asm-generic
1217asm-generic := -f $(srctree)/scripts/Makefile.asm-headers obj
1218
1219PHONY += asm-generic uapi-asm-generic
1220asm-generic: uapi-asm-generic
1221 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1222 generic=include/asm-generic
1223uapi-asm-generic:
1224 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1225 generic=include/uapi/asm-generic
1226
1227# Generate some files
1228# ---------------------------------------------------------------------------
1229
1230# KERNELRELEASE can change from a few different places, meaning version.h
1231# needs to be updated, so this check is forced on all builds
1232
1233uts_len := 64
1234define filechk_utsrelease.h
1235 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1236 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1237 exit 1; \
1238 fi; \
1239 echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1240endef
1241
1242define filechk_version.h
1243 if [ $(SUBLEVEL) -gt 255 ]; then \
1244 echo \#define LINUX_VERSION_CODE $(shell \
1245 expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1246 else \
1247 echo \#define LINUX_VERSION_CODE $(shell \
1248 expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1249 fi; \
1250 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + \
1251 ((c) > 255 ? 255 : (c)))'; \
1252 echo \#define LINUX_VERSION_MAJOR $(VERSION); \
1253 echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL); \
1254 echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1255endef
1256
1257$(version_h): private PATCHLEVEL := $(or $(PATCHLEVEL), 0)
1258$(version_h): private SUBLEVEL := $(or $(SUBLEVEL), 0)
1259$(version_h): FORCE
1260 $(call filechk,version.h)
1261
1262include/generated/utsrelease.h: include/config/kernel.release FORCE
1263 $(call filechk,utsrelease.h)
1264
1265filechk_compile.h = $(srctree)/scripts/mkcompile_h \
1266 "$(UTS_MACHINE)" "$(CONFIG_CC_VERSION_TEXT)" "$(LD)"
1267
1268include/generated/compile.h: FORCE
1269 $(call filechk,compile.h)
1270
1271PHONY += headerdep
1272headerdep:
1273 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1274 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1275
1276# ---------------------------------------------------------------------------
1277# Kernel headers
1278
1279#Default location for installed headers
1280export INSTALL_HDR_PATH = $(objtree)/usr
1281
1282quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1283 cmd_headers_install = \
1284 mkdir -p $(INSTALL_HDR_PATH); \
1285 rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1286 usr/include $(INSTALL_HDR_PATH)
1287
1288PHONY += headers_install
1289headers_install: headers
1290 $(call cmd,headers_install)
1291
1292PHONY += archheaders archscripts
1293
1294hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1295
1296PHONY += headers
1297headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1298 $(if $(filter um, $(SRCARCH)), $(error Headers not exportable for UML))
1299 $(Q)$(MAKE) $(hdr-inst)=include/uapi
1300 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1301
1302ifdef CONFIG_HEADERS_INSTALL
1303prepare: headers
1304endif
1305
1306PHONY += scripts_unifdef
1307scripts_unifdef: scripts_basic
1308 $(Q)$(MAKE) $(build)=scripts scripts/unifdef
1309
1310# ---------------------------------------------------------------------------
1311# Install
1312
1313# Many distributions have the custom install script, /sbin/installkernel.
1314# If DKMS is installed, 'make install' will eventually recurse back
1315# to this Makefile to build and install external modules.
1316# Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
1317
1318quiet_cmd_install = INSTALL $(INSTALL_PATH)
1319 cmd_install = unset sub_make_done; $(srctree)/scripts/install.sh
1320
1321# ---------------------------------------------------------------------------
1322# vDSO install
1323
1324PHONY += vdso_install
1325vdso_install: export INSTALL_FILES = $(vdso-install-y)
1326vdso_install:
1327 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vdsoinst
1328
1329# ---------------------------------------------------------------------------
1330# Tools
1331
1332ifdef CONFIG_OBJTOOL
1333prepare: tools/objtool
1334endif
1335
1336ifdef CONFIG_BPF
1337ifdef CONFIG_DEBUG_INFO_BTF
1338prepare: tools/bpf/resolve_btfids
1339endif
1340endif
1341
1342# The tools build system is not a part of Kbuild and tends to introduce
1343# its own unique issues. If you need to integrate a new tool into Kbuild,
1344# please consider locating that tool outside the tools/ tree and using the
1345# standard Kbuild "hostprogs" syntax instead of adding a new tools/* entry
1346# here. See Documentation/kbuild/makefiles.rst for details.
1347
1348PHONY += resolve_btfids_clean
1349
1350resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1351
1352# tools/bpf/resolve_btfids directory might not exist
1353# in output directory, skip its clean in that case
1354resolve_btfids_clean:
1355ifneq ($(wildcard $(resolve_btfids_O)),)
1356 $(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1357endif
1358
1359# Clear a bunch of variables before executing the submake
1360ifeq ($(quiet),silent_)
1361tools_silent=s
1362endif
1363
1364tools/: FORCE
1365 $(Q)mkdir -p $(objtree)/tools
1366 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1367
1368tools/%: FORCE
1369 $(Q)mkdir -p $(objtree)/tools
1370 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1371
1372# ---------------------------------------------------------------------------
1373# Kernel selftest
1374
1375PHONY += kselftest
1376kselftest: headers
1377 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1378
1379kselftest-%: headers FORCE
1380 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1381
1382PHONY += kselftest-merge
1383kselftest-merge:
1384 $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1385 $(Q)find $(srctree)/tools/testing/selftests -name config -o -name config.$(UTS_MACHINE) | \
1386 xargs $(srctree)/scripts/kconfig/merge_config.sh -y -m $(objtree)/.config
1387 $(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1388
1389# ---------------------------------------------------------------------------
1390# Devicetree files
1391
1392ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1393dtstree := arch/$(SRCARCH)/boot/dts
1394endif
1395
1396ifneq ($(dtstree),)
1397
1398%.dtb: dtbs_prepare
1399 $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1400
1401%.dtbo: dtbs_prepare
1402 $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1403
1404PHONY += dtbs dtbs_prepare dtbs_install dtbs_check
1405dtbs: dtbs_prepare
1406 $(Q)$(MAKE) $(build)=$(dtstree) need-dtbslist=1
1407
1408# include/config/kernel.release is actually needed when installing DTBs because
1409# INSTALL_DTBS_PATH contains $(KERNELRELEASE). However, we do not want to make
1410# dtbs_install depend on it as dtbs_install may run as root.
1411dtbs_prepare: include/config/kernel.release scripts_dtc
1412
1413ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1414export CHECK_DTBS=y
1415endif
1416
1417ifneq ($(CHECK_DTBS),)
1418dtbs_prepare: dt_binding_schemas
1419endif
1420
1421dtbs_check: dtbs
1422
1423dtbs_install:
1424 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.dtbinst obj=$(dtstree)
1425
1426ifdef CONFIG_OF_EARLY_FLATTREE
1427all: dtbs
1428endif
1429
1430endif
1431
1432PHONY += scripts_dtc
1433scripts_dtc: scripts_basic
1434 $(Q)$(MAKE) $(build)=scripts/dtc
1435
1436ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1437export CHECK_DTBS=y
1438endif
1439
1440PHONY += dt_binding_check dt_binding_schemas
1441dt_binding_check: dt_binding_schemas scripts_dtc
1442 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1443
1444dt_binding_schemas:
1445 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1446
1447PHONY += dt_compatible_check
1448dt_compatible_check: dt_binding_schemas
1449 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1450
1451# ---------------------------------------------------------------------------
1452# Modules
1453
1454ifdef CONFIG_MODULES
1455
1456# By default, build modules as well
1457
1458all: modules
1459
1460# When we're building modules with modversions, we need to consider
1461# the built-in objects during the descend as well, in order to
1462# make sure the checksums are up to date before we record them.
1463ifdef CONFIG_MODVERSIONS
1464 KBUILD_BUILTIN := 1
1465endif
1466
1467# Build modules
1468#
1469
1470# *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFO_BTF_MODULES
1471# is an exception.
1472ifdef CONFIG_DEBUG_INFO_BTF_MODULES
1473KBUILD_BUILTIN := 1
1474modules: vmlinux
1475endif
1476
1477modules: modules_prepare
1478
1479# Target to prepare building external modules
1480modules_prepare: prepare
1481 $(Q)$(MAKE) $(build)=scripts scripts/module.lds
1482
1483endif # CONFIG_MODULES
1484
1485###
1486# Cleaning is done on three levels.
1487# make clean Delete most generated files
1488# Leave enough to build external modules
1489# make mrproper Delete the current configuration, and all generated files
1490# make distclean Remove editor backup files, patch leftover files and the like
1491
1492# Directories & files removed with 'make clean'
1493CLEAN_FILES += vmlinux.symvers modules-only.symvers \
1494 modules.builtin modules.builtin.modinfo modules.nsdeps \
1495 modules.builtin.ranges vmlinux.o.map \
1496 compile_commands.json rust/test \
1497 rust-project.json .vmlinux.objs .vmlinux.export.c
1498
1499# Directories & files removed with 'make mrproper'
1500MRPROPER_FILES += include/config include/generated \
1501 arch/$(SRCARCH)/include/generated .objdiff \
1502 debian snap tar-install PKGBUILD pacman \
1503 .config .config.old .version \
1504 Module.symvers \
1505 certs/signing_key.pem \
1506 certs/x509.genkey \
1507 vmlinux-gdb.py \
1508 rpmbuild \
1509 rust/libmacros.so
1510
1511# clean - Delete most, but leave enough to build external modules
1512#
1513clean: private rm-files := $(CLEAN_FILES)
1514
1515PHONY += archclean vmlinuxclean
1516
1517vmlinuxclean:
1518 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1519 $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1520
1521clean: archclean vmlinuxclean resolve_btfids_clean
1522
1523# mrproper - Delete all generated files, including .config
1524#
1525mrproper: private rm-files := $(MRPROPER_FILES)
1526mrproper-dirs := $(addprefix _mrproper_,scripts)
1527
1528PHONY += $(mrproper-dirs) mrproper
1529$(mrproper-dirs):
1530 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1531
1532mrproper: clean $(mrproper-dirs)
1533 $(call cmd,rmfiles)
1534 @find . $(RCS_FIND_IGNORE) \
1535 \( -name '*.rmeta' \) \
1536 -type f -print | xargs rm -f
1537
1538# distclean
1539#
1540PHONY += distclean
1541
1542distclean: mrproper
1543 @find . $(RCS_FIND_IGNORE) \
1544 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1545 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1546 -o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1547 -o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1548 -type f -print | xargs rm -f
1549
1550
1551# Packaging of the kernel to various formats
1552# ---------------------------------------------------------------------------
1553
1554%src-pkg: FORCE
1555 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1556%pkg: include/config/kernel.release FORCE
1557 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1558
1559# Brief documentation of the typical targets used
1560# ---------------------------------------------------------------------------
1561
1562boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1563boards := $(sort $(notdir $(boards)))
1564board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1565board-dirs := $(sort $(notdir $(board-dirs:/=)))
1566
1567PHONY += help
1568help:
1569 @echo 'Cleaning targets:'
1570 @echo ' clean - Remove most generated files but keep the config and'
1571 @echo ' enough build support to build external modules'
1572 @echo ' mrproper - Remove all generated files + config + various backup files'
1573 @echo ' distclean - mrproper + remove editor backup and patch files'
1574 @echo ''
1575 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1576 @echo ''
1577 @echo 'Other generic targets:'
1578 @echo ' all - Build all targets marked with [*]'
1579 @echo '* vmlinux - Build the bare kernel'
1580 @echo '* modules - Build all modules'
1581 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1582 @echo ' vdso_install - Install unstripped vdso to INSTALL_MOD_PATH (default: /)'
1583 @echo ' dir/ - Build all files in dir and below'
1584 @echo ' dir/file.[ois] - Build specified target only'
1585 @echo ' dir/file.ll - Build the LLVM assembly file'
1586 @echo ' (requires compiler support for LLVM assembly generation)'
1587 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1588 @echo ' (requires a recent binutils and recent build (System.map))'
1589 @echo ' dir/file.ko - Build module including final link'
1590 @echo ' modules_prepare - Set up for building external modules'
1591 @echo ' tags/TAGS - Generate tags file for editors'
1592 @echo ' cscope - Generate cscope index'
1593 @echo ' gtags - Generate GNU GLOBAL index'
1594 @echo ' kernelrelease - Output the release version string (use with make -s)'
1595 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1596 @echo ' image_name - Output the image name (use with make -s)'
1597 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1598 echo ' (default: $(INSTALL_HDR_PATH))'; \
1599 echo ''
1600 @echo 'Static analysers:'
1601 @echo ' checkstack - Generate a list of stack hogs and consider all functions'
1602 @echo ' with a stack size larger than MINSTACKSIZE (default: 100)'
1603 @echo ' versioncheck - Sanity check on version.h usage'
1604 @echo ' includecheck - Check for duplicate included header files'
1605 @echo ' export_report - List the usages of all exported symbols'
1606 @echo ' headerdep - Detect inclusion cycles in headers'
1607 @echo ' coccicheck - Check with Coccinelle'
1608 @echo ' clang-analyzer - Check with clang static analyzer'
1609 @echo ' clang-tidy - Check with clang-tidy'
1610 @echo ''
1611 @echo 'Tools:'
1612 @echo ' nsdeps - Generate missing symbol namespace dependencies'
1613 @echo ''
1614 @echo 'Kernel selftest:'
1615 @echo ' kselftest - Build and run kernel selftest'
1616 @echo ' Build, install, and boot kernel before'
1617 @echo ' running kselftest on it'
1618 @echo ' Run as root for full coverage'
1619 @echo ' kselftest-all - Build kernel selftest'
1620 @echo ' kselftest-install - Build and install kernel selftest'
1621 @echo ' kselftest-clean - Remove all generated kselftest files'
1622 @echo ' kselftest-merge - Merge all the config dependencies of'
1623 @echo ' kselftest to existing .config.'
1624 @echo ''
1625 @echo 'Rust targets:'
1626 @echo ' rustavailable - Checks whether the Rust toolchain is'
1627 @echo ' available and, if not, explains why.'
1628 @echo ' rustfmt - Reformat all the Rust code in the kernel'
1629 @echo ' rustfmtcheck - Checks if all the Rust code in the kernel'
1630 @echo ' is formatted, printing a diff otherwise.'
1631 @echo ' rustdoc - Generate Rust documentation'
1632 @echo ' (requires kernel .config)'
1633 @echo ' rusttest - Runs the Rust tests'
1634 @echo ' (requires kernel .config; downloads external repos)'
1635 @echo ' rust-analyzer - Generate rust-project.json rust-analyzer support file'
1636 @echo ' (requires kernel .config)'
1637 @echo ' dir/file.[os] - Build specified target only'
1638 @echo ' dir/file.rsi - Build macro expanded source, similar to C preprocessing.'
1639 @echo ' Run with RUSTFMT=n to skip reformatting if needed.'
1640 @echo ' The output is not intended to be compilable.'
1641 @echo ' dir/file.ll - Build the LLVM assembly file'
1642 @echo ''
1643 @$(if $(dtstree), \
1644 echo 'Devicetree:'; \
1645 echo '* dtbs - Build device tree blobs for enabled boards'; \
1646 echo ' dtbs_install - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1647 echo ' dt_binding_check - Validate device tree binding documents and examples'; \
1648 echo ' dt_binding_schemas - Build processed device tree binding schemas'; \
1649 echo ' dtbs_check - Validate device tree source files';\
1650 echo '')
1651
1652 @echo 'Userspace tools targets:'
1653 @echo ' use "make tools/help"'
1654 @echo ' or "cd tools; make help"'
1655 @echo ''
1656 @echo 'Kernel packaging:'
1657 @$(MAKE) -f $(srctree)/scripts/Makefile.package help
1658 @echo ''
1659 @echo 'Documentation targets:'
1660 @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1661 @echo ''
1662 @echo 'Architecture-specific targets ($(SRCARCH)):'
1663 @$(or $(archhelp),\
1664 echo ' No architecture-specific help defined for $(SRCARCH)')
1665 @echo ''
1666 @$(if $(boards), \
1667 $(foreach b, $(boards), \
1668 printf " %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1669 echo '')
1670 @$(if $(board-dirs), \
1671 $(foreach b, $(board-dirs), \
1672 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1673 printf " %-16s - Show all of the above\\n" help-boards; \
1674 echo '')
1675
1676 @echo ' make V=n [targets] 1: verbose build'
1677 @echo ' 2: give reason for rebuild of target'
1678 @echo ' V=1 and V=2 can be combined with V=12'
1679 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1680 @echo ' make C=1 [targets] Check re-compiled c source with $$CHECK'
1681 @echo ' (sparse by default)'
1682 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1683 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1684 @echo ' make W=n [targets] Enable extra build checks, n=1,2,3,c,e where'
1685 @echo ' 1: warnings which may be relevant and do not occur too often'
1686 @echo ' 2: warnings which occur quite often but may still be relevant'
1687 @echo ' 3: more obscure warnings, can most likely be ignored'
1688 @echo ' c: extra checks in the configuration stage (Kconfig)'
1689 @echo ' e: warnings are being treated as errors'
1690 @echo ' Multiple levels can be combined with W=12 or W=123'
1691 @$(if $(dtstree), \
1692 echo ' make CHECK_DTBS=1 [targets] Check all generated dtb files against schema'; \
1693 echo ' This can be applied both to "dtbs" and to individual "foo.dtb" targets' ; \
1694 )
1695 @echo ''
1696 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1697 @echo 'For further info see the ./README file'
1698
1699
1700help-board-dirs := $(addprefix help-,$(board-dirs))
1701
1702help-boards: $(help-board-dirs)
1703
1704boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1705
1706$(help-board-dirs): help-%:
1707 @echo 'Architecture-specific targets ($(SRCARCH) $*):'
1708 @$(if $(boards-per-dir), \
1709 $(foreach b, $(boards-per-dir), \
1710 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1711 echo '')
1712
1713
1714# Documentation targets
1715# ---------------------------------------------------------------------------
1716DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1717 linkcheckdocs dochelp refcheckdocs texinfodocs infodocs
1718PHONY += $(DOC_TARGETS)
1719$(DOC_TARGETS):
1720 $(Q)$(MAKE) $(build)=Documentation $@
1721
1722
1723# Rust targets
1724# ---------------------------------------------------------------------------
1725
1726# "Is Rust available?" target
1727PHONY += rustavailable
1728rustavailable:
1729 +$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh && echo "Rust is available!"
1730
1731# Documentation target
1732#
1733# Using the singular to avoid running afoul of `no-dot-config-targets`.
1734PHONY += rustdoc
1735rustdoc: prepare
1736 $(Q)$(MAKE) $(build)=rust $@
1737
1738# Testing target
1739PHONY += rusttest
1740rusttest: prepare
1741 $(Q)$(MAKE) $(build)=rust $@
1742
1743# Formatting targets
1744PHONY += rustfmt rustfmtcheck
1745
1746# We skip `rust/alloc` since we want to minimize the diff w.r.t. upstream.
1747#
1748# We match using absolute paths since `find` does not resolve them
1749# when matching, which is a problem when e.g. `srctree` is `..`.
1750# We `grep` afterwards in order to remove the directory entry itself.
1751rustfmt:
1752 $(Q)find $(abs_srctree) -type f -name '*.rs' \
1753 -o -path $(abs_srctree)/rust/alloc -prune \
1754 -o -path $(abs_objtree)/rust/test -prune \
1755 | grep -Fv $(abs_srctree)/rust/alloc \
1756 | grep -Fv $(abs_objtree)/rust/test \
1757 | grep -Fv generated \
1758 | xargs $(RUSTFMT) $(rustfmt_flags)
1759
1760rustfmtcheck: rustfmt_flags = --check
1761rustfmtcheck: rustfmt
1762
1763# Misc
1764# ---------------------------------------------------------------------------
1765
1766PHONY += misc-check
1767misc-check:
1768 $(Q)$(srctree)/scripts/misc-check
1769
1770all: misc-check
1771
1772PHONY += scripts_gdb
1773scripts_gdb: prepare0
1774 $(Q)$(MAKE) $(build)=scripts/gdb
1775 $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1776
1777ifdef CONFIG_GDB_SCRIPTS
1778all: scripts_gdb
1779endif
1780
1781else # KBUILD_EXTMOD
1782
1783filechk_kernel.release = echo $(KERNELRELEASE)
1784
1785###
1786# External module support.
1787# When building external modules the kernel used as basis is considered
1788# read-only, and no consistency checks are made and the make
1789# system is not used on the basis kernel. If updates are required
1790# in the basis kernel ordinary make commands (without M=...) must be used.
1791
1792# We are always building only modules.
1793KBUILD_BUILTIN :=
1794KBUILD_MODULES := 1
1795
1796build-dir := $(KBUILD_EXTMOD)
1797
1798compile_commands.json: $(extmod_prefix)compile_commands.json
1799PHONY += compile_commands.json
1800
1801clean-dirs := $(KBUILD_EXTMOD)
1802clean: private rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1803 $(KBUILD_EXTMOD)/compile_commands.json
1804
1805PHONY += prepare
1806# now expand this into a simple variable to reduce the cost of shell evaluations
1807prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT)
1808prepare:
1809 @if [ "$(CC_VERSION_TEXT)" != "$(CONFIG_CC_VERSION_TEXT)" ]; then \
1810 echo >&2 "warning: the compiler differs from the one used to build the kernel"; \
1811 echo >&2 " The kernel was built by: $(CONFIG_CC_VERSION_TEXT)"; \
1812 echo >&2 " You are using: $(CC_VERSION_TEXT)"; \
1813 fi
1814
1815PHONY += help
1816help:
1817 @echo ' Building external modules.'
1818 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1819 @echo ''
1820 @echo ' modules - default target, build the module(s)'
1821 @echo ' modules_install - install the module'
1822 @echo ' clean - remove generated files in module directory only'
1823 @echo ' rust-analyzer - generate rust-project.json rust-analyzer support file'
1824 @echo ''
1825
1826ifndef CONFIG_MODULES
1827modules modules_install: __external_modules_error
1828__external_modules_error:
1829 @echo >&2 '***'
1830 @echo >&2 '*** The present kernel disabled CONFIG_MODULES.'
1831 @echo >&2 '*** You cannot build or install external modules.'
1832 @echo >&2 '***'
1833 @false
1834endif
1835
1836endif # KBUILD_EXTMOD
1837
1838# ---------------------------------------------------------------------------
1839# Modules
1840
1841PHONY += modules modules_install modules_sign modules_prepare
1842
1843modules_install:
1844 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst \
1845 sign-only=$(if $(filter modules_install,$(MAKECMDGOALS)),,y)
1846
1847ifeq ($(CONFIG_MODULE_SIG),y)
1848# modules_sign is a subset of modules_install.
1849# 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1850modules_sign: modules_install
1851 @:
1852else
1853modules_sign:
1854 @echo >&2 '***'
1855 @echo >&2 '*** CONFIG_MODULE_SIG is disabled. You cannot sign modules.'
1856 @echo >&2 '***'
1857 @false
1858endif
1859
1860ifdef CONFIG_MODULES
1861
1862$(MODORDER): $(build-dir)
1863 @:
1864
1865# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
1866# This is solely useful to speed up test compiles.
1867modules: modpost
1868ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1869 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1870endif
1871
1872PHONY += modules_check
1873modules_check: $(MODORDER)
1874 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1875
1876else # CONFIG_MODULES
1877
1878modules:
1879 @:
1880
1881KBUILD_MODULES :=
1882
1883endif # CONFIG_MODULES
1884
1885PHONY += modpost
1886modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \
1887 $(if $(KBUILD_MODULES), modules_check)
1888 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1889
1890# Single targets
1891# ---------------------------------------------------------------------------
1892# To build individual files in subdirectories, you can do like this:
1893#
1894# make foo/bar/baz.s
1895#
1896# The supported suffixes for single-target are listed in 'single-targets'
1897#
1898# To build only under specific subdirectories, you can do like this:
1899#
1900# make foo/bar/baz/
1901
1902ifdef single-build
1903
1904# .ko is special because modpost is needed
1905single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1906single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \
1907 $(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko)))
1908
1909$(single-ko): single_modules
1910 @:
1911$(single-no-ko): $(build-dir)
1912 @:
1913
1914# Remove MODORDER when done because it is not the real one.
1915PHONY += single_modules
1916single_modules: $(single-no-ko) modules_prepare
1917 $(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$(m:%.ko=%.o);) } > $(MODORDER)
1918 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1919ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1920 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1921endif
1922 $(Q)rm -f $(MODORDER)
1923
1924single-goals := $(addprefix $(build-dir)/, $(single-no-ko))
1925
1926KBUILD_MODULES := 1
1927
1928endif
1929
1930# Preset locale variables to speed up the build process. Limit locale
1931# tweaks to this spot to avoid wrong language settings when running
1932# make menuconfig etc.
1933# Error messages still appears in the original language
1934PHONY += $(build-dir)
1935$(build-dir): prepare
1936 $(Q)$(MAKE) $(build)=$@ need-builtin=1 need-modorder=1 $(single-goals)
1937
1938clean-dirs := $(addprefix _clean_, $(clean-dirs))
1939PHONY += $(clean-dirs) clean
1940$(clean-dirs):
1941 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1942
1943clean: $(clean-dirs)
1944 $(call cmd,rmfiles)
1945 @find $(or $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1946 \( -name '*.[aios]' -o -name '*.rsi' -o -name '*.ko' -o -name '.*.cmd' \
1947 -o -name '*.ko.*' \
1948 -o -name '*.dtb' -o -name '*.dtbo' \
1949 -o -name '*.dtb.S' -o -name '*.dtbo.S' \
1950 -o -name '*.dt.yaml' -o -name 'dtbs-list' \
1951 -o -name '*.dwo' -o -name '*.lst' \
1952 -o -name '*.su' -o -name '*.mod' \
1953 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1954 -o -name '*.lex.c' -o -name '*.tab.[ch]' \
1955 -o -name '*.asn1.[ch]' \
1956 -o -name '*.symtypes' -o -name 'modules.order' \
1957 -o -name '*.c.[012]*.*' \
1958 -o -name '*.ll' \
1959 -o -name '*.gcno' \
1960 \) -type f -print \
1961 -o -name '.tmp_*' -print \
1962 | xargs rm -rf
1963
1964# Generate tags for editors
1965# ---------------------------------------------------------------------------
1966quiet_cmd_tags = GEN $@
1967 cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1968
1969tags TAGS cscope gtags: FORCE
1970 $(call cmd,tags)
1971
1972# Generate rust-project.json (a file that describes the structure of non-Cargo
1973# Rust projects) for rust-analyzer (an implementation of the Language Server
1974# Protocol).
1975PHONY += rust-analyzer
1976rust-analyzer:
1977 +$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh
1978 $(Q)$(MAKE) $(build)=rust $@
1979
1980# Script to generate missing namespace dependencies
1981# ---------------------------------------------------------------------------
1982
1983PHONY += nsdeps
1984nsdeps: export KBUILD_NSDEPS=1
1985nsdeps: modules
1986 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1987
1988# Clang Tooling
1989# ---------------------------------------------------------------------------
1990
1991quiet_cmd_gen_compile_commands = GEN $@
1992 cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
1993
1994$(extmod_prefix)compile_commands.json: $(srctree)/scripts/clang-tools/gen_compile_commands.py \
1995 $(if $(KBUILD_EXTMOD),, vmlinux.a $(KBUILD_VMLINUX_LIBS)) \
1996 $(if $(CONFIG_MODULES), $(MODORDER)) FORCE
1997 $(call if_changed,gen_compile_commands)
1998
1999targets += $(extmod_prefix)compile_commands.json
2000
2001PHONY += clang-tidy clang-analyzer
2002
2003ifdef CONFIG_CC_IS_CLANG
2004quiet_cmd_clang_tools = CHECK $<
2005 cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
2006
2007clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
2008 $(call cmd,clang_tools)
2009else
2010clang-tidy clang-analyzer:
2011 @echo "$@ requires CC=clang" >&2
2012 @false
2013endif
2014
2015# Scripts to check various things for consistency
2016# ---------------------------------------------------------------------------
2017
2018PHONY += includecheck versioncheck coccicheck export_report
2019
2020includecheck:
2021 find $(srctree)/* $(RCS_FIND_IGNORE) \
2022 -name '*.[hcS]' -type f -print | sort \
2023 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
2024
2025versioncheck:
2026 find $(srctree)/* $(RCS_FIND_IGNORE) \
2027 -name '*.[hcS]' -type f -print | sort \
2028 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
2029
2030coccicheck:
2031 $(Q)$(BASH) $(srctree)/scripts/$@
2032
2033export_report:
2034 $(PERL) $(srctree)/scripts/export_report.pl
2035
2036PHONY += checkstack kernelrelease kernelversion image_name
2037
2038# UML needs a little special treatment here. It wants to use the host
2039# toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
2040# else wants $(ARCH), including people doing cross-builds, which means
2041# that $(SUBARCH) doesn't work here.
2042ifeq ($(ARCH), um)
2043CHECKSTACK_ARCH := $(SUBARCH)
2044else
2045CHECKSTACK_ARCH := $(ARCH)
2046endif
2047MINSTACKSIZE ?= 100
2048checkstack:
2049 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
2050 $(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH) $(MINSTACKSIZE)
2051
2052kernelrelease:
2053 @$(filechk_kernel.release)
2054
2055kernelversion:
2056 @echo $(KERNELVERSION)
2057
2058image_name:
2059 @echo $(KBUILD_IMAGE)
2060
2061PHONY += run-command
2062run-command:
2063 $(Q)$(KBUILD_RUN_COMMAND)
2064
2065quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
2066 cmd_rmfiles = rm -rf $(rm-files)
2067
2068# read saved command lines for existing targets
2069existing-targets := $(wildcard $(sort $(targets)))
2070
2071-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
2072
2073endif # config-build
2074endif # mixed-build
2075endif # need-sub-make
2076
2077PHONY += FORCE
2078FORCE:
2079
2080# Declare the contents of the PHONY variable as phony. We keep that
2081# information in a variable so we can use it in if_changed and friends.
2082.PHONY: $(PHONY)