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1# SPDX-License-Identifier: GPL-2.0
2VERSION = 6
3PATCHLEVEL = 8
4SUBLEVEL = 0
5EXTRAVERSION =
6NAME = Hurr durr I'ma ninja sloth
7
8# *DOCUMENTATION*
9# To see a list of typical targets execute "make help"
10# More info can be located in ./README
11# Comments in this file are targeted only to the developer, do not
12# expect to learn how to build the kernel reading this file.
13
14ifeq ($(filter undefine,$(.FEATURES)),)
15$(error GNU Make >= 3.82 is required. Your Make version is $(MAKE_VERSION))
16endif
17
18$(if $(filter __%, $(MAKECMDGOALS)), \
19 $(error targets prefixed with '__' are only for internal use))
20
21# That's our default target when none is given on the command line
22PHONY := __all
23__all:
24
25# We are using a recursive build, so we need to do a little thinking
26# to get the ordering right.
27#
28# Most importantly: sub-Makefiles should only ever modify files in
29# their own directory. If in some directory we have a dependency on
30# a file in another dir (which doesn't happen often, but it's often
31# unavoidable when linking the built-in.a targets which finally
32# turn into vmlinux), we will call a sub make in that other dir, and
33# after that we are sure that everything which is in that other dir
34# is now up to date.
35#
36# The only cases where we need to modify files which have global
37# effects are thus separated out and done before the recursive
38# descending is started. They are now explicitly listed as the
39# prepare rule.
40
41this-makefile := $(lastword $(MAKEFILE_LIST))
42export abs_srctree := $(realpath $(dir $(this-makefile)))
43export abs_objtree := $(CURDIR)
44
45ifneq ($(sub_make_done),1)
46
47# Do not use make's built-in rules and variables
48# (this increases performance and avoids hard-to-debug behaviour)
49MAKEFLAGS += -rR
50
51# Avoid funny character set dependencies
52unexport LC_ALL
53LC_COLLATE=C
54LC_NUMERIC=C
55export LC_COLLATE LC_NUMERIC
56
57# Avoid interference with shell env settings
58unexport GREP_OPTIONS
59
60# Beautify output
61# ---------------------------------------------------------------------------
62#
63# Most of build commands in Kbuild start with "cmd_". You can optionally define
64# "quiet_cmd_*". If defined, the short log is printed. Otherwise, no log from
65# that command is printed by default.
66#
67# e.g.)
68# quiet_cmd_depmod = DEPMOD $(MODLIB)
69# cmd_depmod = $(srctree)/scripts/depmod.sh $(DEPMOD) $(KERNELRELEASE)
70#
71# A simple variant is to prefix commands with $(Q) - that's useful
72# for commands that shall be hidden in non-verbose mode.
73#
74# $(Q)$(MAKE) $(build)=scripts/basic
75#
76# If KBUILD_VERBOSE contains 1, the whole command is echoed.
77# If KBUILD_VERBOSE contains 2, the reason for rebuilding is printed.
78#
79# To put more focus on warnings, be less verbose as default
80# Use 'make V=1' to see the full commands
81
82ifeq ("$(origin V)", "command line")
83 KBUILD_VERBOSE = $(V)
84endif
85
86quiet = quiet_
87Q = @
88
89ifneq ($(findstring 1, $(KBUILD_VERBOSE)),)
90 quiet =
91 Q =
92endif
93
94# If the user is running make -s (silent mode), suppress echoing of
95# commands
96# make-4.0 (and later) keep single letter options in the 1st word of MAKEFLAGS.
97
98ifeq ($(filter 3.%,$(MAKE_VERSION)),)
99short-opts := $(firstword -$(MAKEFLAGS))
100else
101short-opts := $(filter-out --%,$(MAKEFLAGS))
102endif
103
104ifneq ($(findstring s,$(short-opts)),)
105quiet=silent_
106override KBUILD_VERBOSE :=
107endif
108
109export quiet Q KBUILD_VERBOSE
110
111# Call a source code checker (by default, "sparse") as part of the
112# C compilation.
113#
114# Use 'make C=1' to enable checking of only re-compiled files.
115# Use 'make C=2' to enable checking of *all* source files, regardless
116# of whether they are re-compiled or not.
117#
118# See the file "Documentation/dev-tools/sparse.rst" for more details,
119# including where to get the "sparse" utility.
120
121ifeq ("$(origin C)", "command line")
122 KBUILD_CHECKSRC = $(C)
123endif
124ifndef KBUILD_CHECKSRC
125 KBUILD_CHECKSRC = 0
126endif
127
128export KBUILD_CHECKSRC
129
130# Enable "clippy" (a linter) as part of the Rust compilation.
131#
132# Use 'make CLIPPY=1' to enable it.
133ifeq ("$(origin CLIPPY)", "command line")
134 KBUILD_CLIPPY := $(CLIPPY)
135endif
136
137export KBUILD_CLIPPY
138
139# Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
140# directory of external module to build. Setting M= takes precedence.
141ifeq ("$(origin M)", "command line")
142 KBUILD_EXTMOD := $(M)
143endif
144
145$(if $(word 2, $(KBUILD_EXTMOD)), \
146 $(error building multiple external modules is not supported))
147
148$(foreach x, % :, $(if $(findstring $x, $(KBUILD_EXTMOD)), \
149 $(error module directory path cannot contain '$x')))
150
151# Remove trailing slashes
152ifneq ($(filter %/, $(KBUILD_EXTMOD)),)
153KBUILD_EXTMOD := $(shell dirname $(KBUILD_EXTMOD).)
154endif
155
156export KBUILD_EXTMOD
157
158# backward compatibility
159KBUILD_EXTRA_WARN ?= $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)
160
161ifeq ("$(origin W)", "command line")
162 KBUILD_EXTRA_WARN := $(W)
163endif
164
165export KBUILD_EXTRA_WARN
166
167# Kbuild will save output files in the current working directory.
168# This does not need to match to the root of the kernel source tree.
169#
170# For example, you can do this:
171#
172# cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
173#
174# If you want to save output files in a different location, there are
175# two syntaxes to specify it.
176#
177# 1) O=
178# Use "make O=dir/to/store/output/files/"
179#
180# 2) Set KBUILD_OUTPUT
181# Set the environment variable KBUILD_OUTPUT to point to the output directory.
182# export KBUILD_OUTPUT=dir/to/store/output/files/; make
183#
184# The O= assignment takes precedence over the KBUILD_OUTPUT environment
185# variable.
186
187# Do we want to change the working directory?
188ifeq ("$(origin O)", "command line")
189 KBUILD_OUTPUT := $(O)
190endif
191
192ifneq ($(KBUILD_OUTPUT),)
193# $(realpath ...) gets empty if the path does not exist. Run 'mkdir -p' first.
194$(shell mkdir -p "$(KBUILD_OUTPUT)")
195# $(realpath ...) resolves symlinks
196abs_objtree := $(realpath $(KBUILD_OUTPUT))
197$(if $(abs_objtree),,$(error failed to create output directory "$(KBUILD_OUTPUT)"))
198endif # ifneq ($(KBUILD_OUTPUT),)
199
200ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
201$(error source directory cannot contain spaces or colons)
202endif
203
204ifneq ($(filter 3.%,$(MAKE_VERSION)),)
205# 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
206# We need to invoke sub-make to avoid implicit rules in the top Makefile.
207need-sub-make := 1
208# Cancel implicit rules for this Makefile.
209$(this-makefile): ;
210endif
211
212export sub_make_done := 1
213
214endif # sub_make_done
215
216ifeq ($(abs_objtree),$(CURDIR))
217# Suppress "Entering directory ..." if we are at the final work directory.
218no-print-directory := --no-print-directory
219else
220# Recursion to show "Entering directory ..."
221need-sub-make := 1
222endif
223
224ifeq ($(filter --no-print-directory, $(MAKEFLAGS)),)
225# If --no-print-directory is unset, recurse once again to set it.
226# You may end up recursing into __sub-make twice. This is needed due to the
227# behavior change in GNU Make 4.4.1.
228need-sub-make := 1
229endif
230
231ifeq ($(need-sub-make),1)
232
233PHONY += $(MAKECMDGOALS) __sub-make
234
235$(filter-out $(this-makefile), $(MAKECMDGOALS)) __all: __sub-make
236 @:
237
238# Invoke a second make in the output directory, passing relevant variables
239__sub-make:
240 $(Q)$(MAKE) $(no-print-directory) -C $(abs_objtree) \
241 -f $(abs_srctree)/Makefile $(MAKECMDGOALS)
242
243else # need-sub-make
244
245# We process the rest of the Makefile if this is the final invocation of make
246
247ifeq ($(abs_srctree),$(abs_objtree))
248 # building in the source tree
249 srctree := .
250 building_out_of_srctree :=
251else
252 ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
253 # building in a subdirectory of the source tree
254 srctree := ..
255 else
256 srctree := $(abs_srctree)
257 endif
258 building_out_of_srctree := 1
259endif
260
261ifneq ($(KBUILD_ABS_SRCTREE),)
262srctree := $(abs_srctree)
263endif
264
265objtree := .
266VPATH := $(srctree)
267
268export building_out_of_srctree srctree objtree VPATH
269
270# To make sure we do not include .config for any of the *config targets
271# catch them early, and hand them over to scripts/kconfig/Makefile
272# It is allowed to specify more targets when calling make, including
273# mixing *config targets and build targets.
274# For example 'make oldconfig all'.
275# Detect when mixed targets is specified, and make a second invocation
276# of make so .config is not included in this case either (for *config).
277
278version_h := include/generated/uapi/linux/version.h
279
280clean-targets := %clean mrproper cleandocs
281no-dot-config-targets := $(clean-targets) \
282 cscope gtags TAGS tags help% %docs check% coccicheck \
283 $(version_h) headers headers_% archheaders archscripts \
284 %asm-generic kernelversion %src-pkg dt_binding_check \
285 outputmakefile rustavailable rustfmt rustfmtcheck
286no-sync-config-targets := $(no-dot-config-targets) %install modules_sign kernelrelease \
287 image_name
288single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.rsi %.s %.symtypes %/
289
290config-build :=
291mixed-build :=
292need-config := 1
293may-sync-config := 1
294single-build :=
295
296ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
297 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
298 need-config :=
299 endif
300endif
301
302ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
303 ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
304 may-sync-config :=
305 endif
306endif
307
308need-compiler := $(may-sync-config)
309
310ifneq ($(KBUILD_EXTMOD),)
311 may-sync-config :=
312endif
313
314ifeq ($(KBUILD_EXTMOD),)
315 ifneq ($(filter %config,$(MAKECMDGOALS)),)
316 config-build := 1
317 ifneq ($(words $(MAKECMDGOALS)),1)
318 mixed-build := 1
319 endif
320 endif
321endif
322
323# We cannot build single targets and the others at the same time
324ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
325 single-build := 1
326 ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
327 mixed-build := 1
328 endif
329endif
330
331# For "make -j clean all", "make -j mrproper defconfig all", etc.
332ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
333 ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
334 mixed-build := 1
335 endif
336endif
337
338# install and modules_install need also be processed one by one
339ifneq ($(filter install,$(MAKECMDGOALS)),)
340 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
341 mixed-build := 1
342 endif
343endif
344
345ifdef mixed-build
346# ===========================================================================
347# We're called with mixed targets (*config and build targets).
348# Handle them one by one.
349
350PHONY += $(MAKECMDGOALS) __build_one_by_one
351
352$(MAKECMDGOALS): __build_one_by_one
353 @:
354
355__build_one_by_one:
356 $(Q)set -e; \
357 for i in $(MAKECMDGOALS); do \
358 $(MAKE) -f $(srctree)/Makefile $$i; \
359 done
360
361else # !mixed-build
362
363include $(srctree)/scripts/Kbuild.include
364
365# Read KERNELRELEASE from include/config/kernel.release (if it exists)
366KERNELRELEASE = $(call read-file, include/config/kernel.release)
367KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
368export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
369
370include $(srctree)/scripts/subarch.include
371
372# Cross compiling and selecting different set of gcc/bin-utils
373# ---------------------------------------------------------------------------
374#
375# When performing cross compilation for other architectures ARCH shall be set
376# to the target architecture. (See arch/* for the possibilities).
377# ARCH can be set during invocation of make:
378# make ARCH=arm64
379# Another way is to have ARCH set in the environment.
380# The default ARCH is the host where make is executed.
381
382# CROSS_COMPILE specify the prefix used for all executables used
383# during compilation. Only gcc and related bin-utils executables
384# are prefixed with $(CROSS_COMPILE).
385# CROSS_COMPILE can be set on the command line
386# make CROSS_COMPILE=aarch64-linux-gnu-
387# Alternatively CROSS_COMPILE can be set in the environment.
388# Default value for CROSS_COMPILE is not to prefix executables
389# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
390ARCH ?= $(SUBARCH)
391
392# Architecture as present in compile.h
393UTS_MACHINE := $(ARCH)
394SRCARCH := $(ARCH)
395
396# Additional ARCH settings for x86
397ifeq ($(ARCH),i386)
398 SRCARCH := x86
399endif
400ifeq ($(ARCH),x86_64)
401 SRCARCH := x86
402endif
403
404# Additional ARCH settings for sparc
405ifeq ($(ARCH),sparc32)
406 SRCARCH := sparc
407endif
408ifeq ($(ARCH),sparc64)
409 SRCARCH := sparc
410endif
411
412# Additional ARCH settings for parisc
413ifeq ($(ARCH),parisc64)
414 SRCARCH := parisc
415endif
416
417export cross_compiling :=
418ifneq ($(SRCARCH),$(SUBARCH))
419cross_compiling := 1
420endif
421
422KCONFIG_CONFIG ?= .config
423export KCONFIG_CONFIG
424
425# SHELL used by kbuild
426CONFIG_SHELL := sh
427
428HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
429HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
430HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
431
432ifneq ($(LLVM),)
433ifneq ($(filter %/,$(LLVM)),)
434LLVM_PREFIX := $(LLVM)
435else ifneq ($(filter -%,$(LLVM)),)
436LLVM_SUFFIX := $(LLVM)
437endif
438
439HOSTCC = $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
440HOSTCXX = $(LLVM_PREFIX)clang++$(LLVM_SUFFIX)
441else
442HOSTCC = gcc
443HOSTCXX = g++
444endif
445HOSTRUSTC = rustc
446HOSTPKG_CONFIG = pkg-config
447
448KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
449 -O2 -fomit-frame-pointer -std=gnu11
450KBUILD_USERCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(USERCFLAGS)
451KBUILD_USERLDFLAGS := $(USERLDFLAGS)
452
453# These flags apply to all Rust code in the tree, including the kernel and
454# host programs.
455export rust_common_flags := --edition=2021 \
456 -Zbinary_dep_depinfo=y \
457 -Dunsafe_op_in_unsafe_fn -Drust_2018_idioms \
458 -Dunreachable_pub -Dnon_ascii_idents \
459 -Wmissing_docs \
460 -Drustdoc::missing_crate_level_docs \
461 -Dclippy::correctness -Dclippy::style \
462 -Dclippy::suspicious -Dclippy::complexity \
463 -Dclippy::perf \
464 -Dclippy::let_unit_value -Dclippy::mut_mut \
465 -Dclippy::needless_bitwise_bool \
466 -Dclippy::needless_continue \
467 -Dclippy::no_mangle_with_rust_abi \
468 -Wclippy::dbg_macro
469
470KBUILD_HOSTCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
471KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
472KBUILD_HOSTRUSTFLAGS := $(rust_common_flags) -O -Cstrip=debuginfo \
473 -Zallow-features= $(HOSTRUSTFLAGS)
474KBUILD_HOSTLDFLAGS := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
475KBUILD_HOSTLDLIBS := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
476
477# Make variables (CC, etc...)
478CPP = $(CC) -E
479ifneq ($(LLVM),)
480CC = $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
481LD = $(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX)
482AR = $(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX)
483NM = $(LLVM_PREFIX)llvm-nm$(LLVM_SUFFIX)
484OBJCOPY = $(LLVM_PREFIX)llvm-objcopy$(LLVM_SUFFIX)
485OBJDUMP = $(LLVM_PREFIX)llvm-objdump$(LLVM_SUFFIX)
486READELF = $(LLVM_PREFIX)llvm-readelf$(LLVM_SUFFIX)
487STRIP = $(LLVM_PREFIX)llvm-strip$(LLVM_SUFFIX)
488else
489CC = $(CROSS_COMPILE)gcc
490LD = $(CROSS_COMPILE)ld
491AR = $(CROSS_COMPILE)ar
492NM = $(CROSS_COMPILE)nm
493OBJCOPY = $(CROSS_COMPILE)objcopy
494OBJDUMP = $(CROSS_COMPILE)objdump
495READELF = $(CROSS_COMPILE)readelf
496STRIP = $(CROSS_COMPILE)strip
497endif
498RUSTC = rustc
499RUSTDOC = rustdoc
500RUSTFMT = rustfmt
501CLIPPY_DRIVER = clippy-driver
502BINDGEN = bindgen
503CARGO = cargo
504PAHOLE = pahole
505RESOLVE_BTFIDS = $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
506LEX = flex
507YACC = bison
508AWK = awk
509INSTALLKERNEL := installkernel
510PERL = perl
511PYTHON3 = python3
512CHECK = sparse
513BASH = bash
514KGZIP = gzip
515KBZIP2 = bzip2
516KLZOP = lzop
517LZMA = lzma
518LZ4 = lz4c
519XZ = xz
520ZSTD = zstd
521
522CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
523 -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
524NOSTDINC_FLAGS :=
525CFLAGS_MODULE =
526RUSTFLAGS_MODULE =
527AFLAGS_MODULE =
528LDFLAGS_MODULE =
529CFLAGS_KERNEL =
530RUSTFLAGS_KERNEL =
531AFLAGS_KERNEL =
532LDFLAGS_vmlinux =
533
534# Use USERINCLUDE when you must reference the UAPI directories only.
535USERINCLUDE := \
536 -I$(srctree)/arch/$(SRCARCH)/include/uapi \
537 -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
538 -I$(srctree)/include/uapi \
539 -I$(objtree)/include/generated/uapi \
540 -include $(srctree)/include/linux/compiler-version.h \
541 -include $(srctree)/include/linux/kconfig.h
542
543# Use LINUXINCLUDE when you must reference the include directory.
544# Needed to be compatible with the O= option
545LINUXINCLUDE := \
546 -I$(srctree)/arch/$(SRCARCH)/include \
547 -I$(objtree)/arch/$(SRCARCH)/include/generated \
548 $(if $(building_out_of_srctree),-I$(srctree)/include) \
549 -I$(objtree)/include \
550 $(USERINCLUDE)
551
552KBUILD_AFLAGS := -D__ASSEMBLY__ -fno-PIE
553
554KBUILD_CFLAGS :=
555KBUILD_CFLAGS += -std=gnu11
556KBUILD_CFLAGS += -fshort-wchar
557KBUILD_CFLAGS += -funsigned-char
558KBUILD_CFLAGS += -fno-common
559KBUILD_CFLAGS += -fno-PIE
560KBUILD_CFLAGS += -fno-strict-aliasing
561
562KBUILD_CPPFLAGS := -D__KERNEL__
563KBUILD_RUSTFLAGS := $(rust_common_flags) \
564 --target=$(objtree)/scripts/target.json \
565 -Cpanic=abort -Cembed-bitcode=n -Clto=n \
566 -Cforce-unwind-tables=n -Ccodegen-units=1 \
567 -Csymbol-mangling-version=v0 \
568 -Crelocation-model=static \
569 -Zfunction-sections=n \
570 -Dclippy::float_arithmetic
571
572KBUILD_AFLAGS_KERNEL :=
573KBUILD_CFLAGS_KERNEL :=
574KBUILD_RUSTFLAGS_KERNEL :=
575KBUILD_AFLAGS_MODULE := -DMODULE
576KBUILD_CFLAGS_MODULE := -DMODULE
577KBUILD_RUSTFLAGS_MODULE := --cfg MODULE
578KBUILD_LDFLAGS_MODULE :=
579KBUILD_LDFLAGS :=
580CLANG_FLAGS :=
581
582ifeq ($(KBUILD_CLIPPY),1)
583 RUSTC_OR_CLIPPY_QUIET := CLIPPY
584 RUSTC_OR_CLIPPY = $(CLIPPY_DRIVER)
585else
586 RUSTC_OR_CLIPPY_QUIET := RUSTC
587 RUSTC_OR_CLIPPY = $(RUSTC)
588endif
589
590ifdef RUST_LIB_SRC
591 export RUST_LIB_SRC
592endif
593
594# Allows the usage of unstable features in stable compilers.
595export RUSTC_BOOTSTRAP := 1
596
597export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG
598export RUSTC RUSTDOC RUSTFMT RUSTC_OR_CLIPPY_QUIET RUSTC_OR_CLIPPY BINDGEN CARGO
599export HOSTRUSTC KBUILD_HOSTRUSTFLAGS
600export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
601export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
602export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
603export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
604export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS
605
606export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
607export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
608export KBUILD_RUSTFLAGS RUSTFLAGS_KERNEL RUSTFLAGS_MODULE
609export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
610export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_RUSTFLAGS_MODULE KBUILD_LDFLAGS_MODULE
611export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL KBUILD_RUSTFLAGS_KERNEL
612
613# Files to ignore in find ... statements
614
615export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o \
616 -name CVS -o -name .pc -o -name .hg -o -name .git \) \
617 -prune -o
618
619# ===========================================================================
620# Rules shared between *config targets and build targets
621
622# Basic helpers built in scripts/basic
623PHONY += scripts_basic
624scripts_basic:
625 $(Q)$(MAKE) $(build)=scripts/basic
626
627PHONY += outputmakefile
628ifdef building_out_of_srctree
629# Before starting out-of-tree build, make sure the source tree is clean.
630# outputmakefile generates a Makefile in the output directory, if using a
631# separate output directory. This allows convenient use of make in the
632# output directory.
633# At the same time when output Makefile generated, generate .gitignore to
634# ignore whole output directory
635
636quiet_cmd_makefile = GEN Makefile
637 cmd_makefile = { \
638 echo "\# Automatically generated by $(srctree)/Makefile: don't edit"; \
639 echo "include $(srctree)/Makefile"; \
640 } > Makefile
641
642outputmakefile:
643 @if [ -f $(srctree)/.config -o \
644 -d $(srctree)/include/config -o \
645 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
646 echo >&2 "***"; \
647 echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
648 echo >&2 "*** in $(abs_srctree)";\
649 echo >&2 "***"; \
650 false; \
651 fi
652 $(Q)ln -fsn $(srctree) source
653 $(call cmd,makefile)
654 $(Q)test -e .gitignore || \
655 { echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
656endif
657
658# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
659# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
660# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
661# and from include/config/auto.conf.cmd to detect the compiler upgrade.
662CC_VERSION_TEXT = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1))
663
664ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
665include $(srctree)/scripts/Makefile.clang
666endif
667
668# Include this also for config targets because some architectures need
669# cc-cross-prefix to determine CROSS_COMPILE.
670ifdef need-compiler
671include $(srctree)/scripts/Makefile.compiler
672endif
673
674ifdef config-build
675# ===========================================================================
676# *config targets only - make sure prerequisites are updated, and descend
677# in scripts/kconfig to make the *config target
678
679# Read arch-specific Makefile to set KBUILD_DEFCONFIG as needed.
680# KBUILD_DEFCONFIG may point out an alternative default configuration
681# used for 'make defconfig'
682include $(srctree)/arch/$(SRCARCH)/Makefile
683export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
684
685config: outputmakefile scripts_basic FORCE
686 $(Q)$(MAKE) $(build)=scripts/kconfig $@
687
688%config: outputmakefile scripts_basic FORCE
689 $(Q)$(MAKE) $(build)=scripts/kconfig $@
690
691else #!config-build
692# ===========================================================================
693# Build targets only - this includes vmlinux, arch-specific targets, clean
694# targets and others. In general all targets except *config targets.
695
696# If building an external module we do not care about the all: rule
697# but instead __all depend on modules
698PHONY += all
699ifeq ($(KBUILD_EXTMOD),)
700__all: all
701else
702__all: modules
703endif
704
705targets :=
706
707# Decide whether to build built-in, modular, or both.
708# Normally, just do built-in.
709
710KBUILD_MODULES :=
711KBUILD_BUILTIN := 1
712
713# If we have only "make modules", don't compile built-in objects.
714ifeq ($(MAKECMDGOALS),modules)
715 KBUILD_BUILTIN :=
716endif
717
718# If we have "make <whatever> modules", compile modules
719# in addition to whatever we do anyway.
720# Just "make" or "make all" shall build modules as well
721
722ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
723 KBUILD_MODULES := 1
724endif
725
726ifeq ($(MAKECMDGOALS),)
727 KBUILD_MODULES := 1
728endif
729
730export KBUILD_MODULES KBUILD_BUILTIN
731
732ifdef need-config
733include include/config/auto.conf
734endif
735
736ifeq ($(KBUILD_EXTMOD),)
737# Objects we will link into vmlinux / subdirs we need to visit
738core-y :=
739drivers-y :=
740libs-y := lib
741endif # KBUILD_EXTMOD
742
743# The all: target is the default when no target is given on the
744# command line.
745# This allow a user to issue only 'make' to build a kernel including modules
746# Defaults to vmlinux, but the arch makefile usually adds further targets
747all: vmlinux
748
749CFLAGS_GCOV := -fprofile-arcs -ftest-coverage
750ifdef CONFIG_CC_IS_GCC
751CFLAGS_GCOV += -fno-tree-loop-im
752endif
753export CFLAGS_GCOV
754
755# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
756ifdef CONFIG_FUNCTION_TRACER
757 CC_FLAGS_FTRACE := -pg
758endif
759
760include $(srctree)/arch/$(SRCARCH)/Makefile
761
762ifdef need-config
763ifdef may-sync-config
764# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
765# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
766# because some architectures define CROSS_COMPILE there.
767include include/config/auto.conf.cmd
768
769$(KCONFIG_CONFIG):
770 @echo >&2 '***'
771 @echo >&2 '*** Configuration file "$@" not found!'
772 @echo >&2 '***'
773 @echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
774 @echo >&2 '*** "make menuconfig" or "make xconfig").'
775 @echo >&2 '***'
776 @/bin/false
777
778# The actual configuration files used during the build are stored in
779# include/generated/ and include/config/. Update them if .config is newer than
780# include/config/auto.conf (which mirrors .config).
781#
782# This exploits the 'multi-target pattern rule' trick.
783# The syncconfig should be executed only once to make all the targets.
784# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
785#
786# Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
787# so you cannot notice that Kconfig is waiting for the user input.
788%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h %/generated/rustc_cfg: $(KCONFIG_CONFIG)
789 $(Q)$(kecho) " SYNC $@"
790 $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
791else # !may-sync-config
792# External modules and some install targets need include/generated/autoconf.h
793# and include/config/auto.conf but do not care if they are up-to-date.
794# Use auto.conf to trigger the test
795PHONY += include/config/auto.conf
796
797include/config/auto.conf:
798 @test -e include/generated/autoconf.h -a -e $@ || ( \
799 echo >&2; \
800 echo >&2 " ERROR: Kernel configuration is invalid."; \
801 echo >&2 " include/generated/autoconf.h or $@ are missing.";\
802 echo >&2 " Run 'make oldconfig && make prepare' on kernel src to fix it."; \
803 echo >&2 ; \
804 /bin/false)
805
806endif # may-sync-config
807endif # need-config
808
809KBUILD_CFLAGS += -fno-delete-null-pointer-checks
810
811ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
812KBUILD_CFLAGS += -O2
813KBUILD_RUSTFLAGS += -Copt-level=2
814else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
815KBUILD_CFLAGS += -Os
816KBUILD_RUSTFLAGS += -Copt-level=s
817endif
818
819# Always set `debug-assertions` and `overflow-checks` because their default
820# depends on `opt-level` and `debug-assertions`, respectively.
821KBUILD_RUSTFLAGS += -Cdebug-assertions=$(if $(CONFIG_RUST_DEBUG_ASSERTIONS),y,n)
822KBUILD_RUSTFLAGS += -Coverflow-checks=$(if $(CONFIG_RUST_OVERFLOW_CHECKS),y,n)
823
824# Tell gcc to never replace conditional load with a non-conditional one
825ifdef CONFIG_CC_IS_GCC
826# gcc-10 renamed --param=allow-store-data-races=0 to
827# -fno-allow-store-data-races.
828KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
829KBUILD_CFLAGS += $(call cc-option,-fno-allow-store-data-races)
830endif
831
832ifdef CONFIG_READABLE_ASM
833# Disable optimizations that make assembler listings hard to read.
834# reorder blocks reorders the control in the function
835# ipa clone creates specialized cloned functions
836# partial inlining inlines only parts of functions
837KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
838endif
839
840stackp-flags-y := -fno-stack-protector
841stackp-flags-$(CONFIG_STACKPROTECTOR) := -fstack-protector
842stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG) := -fstack-protector-strong
843
844KBUILD_CFLAGS += $(stackp-flags-y)
845
846KBUILD_RUSTFLAGS-$(CONFIG_WERROR) += -Dwarnings
847KBUILD_RUSTFLAGS += $(KBUILD_RUSTFLAGS-y)
848
849ifdef CONFIG_FRAME_POINTER
850KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
851KBUILD_RUSTFLAGS += -Cforce-frame-pointers=y
852else
853# Some targets (ARM with Thumb2, for example), can't be built with frame
854# pointers. For those, we don't have FUNCTION_TRACER automatically
855# select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
856# incompatible with -fomit-frame-pointer with current GCC, so we don't use
857# -fomit-frame-pointer with FUNCTION_TRACER.
858# In the Rust target specification, "frame-pointer" is set explicitly
859# to "may-omit".
860ifndef CONFIG_FUNCTION_TRACER
861KBUILD_CFLAGS += -fomit-frame-pointer
862endif
863endif
864
865# Initialize all stack variables with a 0xAA pattern.
866ifdef CONFIG_INIT_STACK_ALL_PATTERN
867KBUILD_CFLAGS += -ftrivial-auto-var-init=pattern
868endif
869
870# Initialize all stack variables with a zero value.
871ifdef CONFIG_INIT_STACK_ALL_ZERO
872KBUILD_CFLAGS += -ftrivial-auto-var-init=zero
873ifdef CONFIG_CC_HAS_AUTO_VAR_INIT_ZERO_ENABLER
874# https://github.com/llvm/llvm-project/issues/44842
875CC_AUTO_VAR_INIT_ZERO_ENABLER := -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
876export CC_AUTO_VAR_INIT_ZERO_ENABLER
877KBUILD_CFLAGS += $(CC_AUTO_VAR_INIT_ZERO_ENABLER)
878endif
879endif
880
881# While VLAs have been removed, GCC produces unreachable stack probes
882# for the randomize_kstack_offset feature. Disable it for all compilers.
883KBUILD_CFLAGS += $(call cc-option, -fno-stack-clash-protection)
884
885# Clear used registers at func exit (to reduce data lifetime and ROP gadgets).
886ifdef CONFIG_ZERO_CALL_USED_REGS
887KBUILD_CFLAGS += -fzero-call-used-regs=used-gpr
888endif
889
890ifdef CONFIG_FUNCTION_TRACER
891ifdef CONFIG_FTRACE_MCOUNT_USE_CC
892 CC_FLAGS_FTRACE += -mrecord-mcount
893 ifdef CONFIG_HAVE_NOP_MCOUNT
894 ifeq ($(call cc-option-yn, -mnop-mcount),y)
895 CC_FLAGS_FTRACE += -mnop-mcount
896 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
897 endif
898 endif
899endif
900ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
901 ifdef CONFIG_HAVE_OBJTOOL_NOP_MCOUNT
902 CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
903 endif
904endif
905ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
906 ifdef CONFIG_HAVE_C_RECORDMCOUNT
907 BUILD_C_RECORDMCOUNT := y
908 export BUILD_C_RECORDMCOUNT
909 endif
910endif
911ifdef CONFIG_HAVE_FENTRY
912 # s390-linux-gnu-gcc did not support -mfentry until gcc-9.
913 ifeq ($(call cc-option-yn, -mfentry),y)
914 CC_FLAGS_FTRACE += -mfentry
915 CC_FLAGS_USING += -DCC_USING_FENTRY
916 endif
917endif
918export CC_FLAGS_FTRACE
919KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
920KBUILD_AFLAGS += $(CC_FLAGS_USING)
921endif
922
923# We trigger additional mismatches with less inlining
924ifdef CONFIG_DEBUG_SECTION_MISMATCH
925KBUILD_CFLAGS += -fno-inline-functions-called-once
926endif
927
928# `rustc`'s `-Zfunction-sections` applies to data too (as of 1.59.0).
929ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
930KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
931KBUILD_RUSTFLAGS_KERNEL += -Zfunction-sections=y
932LDFLAGS_vmlinux += --gc-sections
933endif
934
935ifdef CONFIG_SHADOW_CALL_STACK
936ifndef CONFIG_DYNAMIC_SCS
937CC_FLAGS_SCS := -fsanitize=shadow-call-stack
938KBUILD_CFLAGS += $(CC_FLAGS_SCS)
939endif
940export CC_FLAGS_SCS
941endif
942
943ifdef CONFIG_LTO_CLANG
944ifdef CONFIG_LTO_CLANG_THIN
945CC_FLAGS_LTO := -flto=thin -fsplit-lto-unit
946KBUILD_LDFLAGS += --thinlto-cache-dir=$(extmod_prefix).thinlto-cache
947else
948CC_FLAGS_LTO := -flto
949endif
950CC_FLAGS_LTO += -fvisibility=hidden
951
952# Limit inlining across translation units to reduce binary size
953KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
954
955# Check for frame size exceeding threshold during prolog/epilog insertion
956# when using lld < 13.0.0.
957ifneq ($(CONFIG_FRAME_WARN),0)
958ifeq ($(call test-lt, $(CONFIG_LLD_VERSION), 130000),y)
959KBUILD_LDFLAGS += -plugin-opt=-warn-stack-size=$(CONFIG_FRAME_WARN)
960endif
961endif
962endif
963
964ifdef CONFIG_LTO
965KBUILD_CFLAGS += -fno-lto $(CC_FLAGS_LTO)
966KBUILD_AFLAGS += -fno-lto
967export CC_FLAGS_LTO
968endif
969
970ifdef CONFIG_CFI_CLANG
971CC_FLAGS_CFI := -fsanitize=kcfi
972KBUILD_CFLAGS += $(CC_FLAGS_CFI)
973export CC_FLAGS_CFI
974endif
975
976ifneq ($(CONFIG_FUNCTION_ALIGNMENT),0)
977KBUILD_CFLAGS += -falign-functions=$(CONFIG_FUNCTION_ALIGNMENT)
978endif
979
980# arch Makefile may override CC so keep this after arch Makefile is included
981NOSTDINC_FLAGS += -nostdinc
982
983# To gain proper coverage for CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE,
984# the kernel uses only C99 flexible arrays for dynamically sized trailing
985# arrays. Enforce this for everything that may examine structure sizes and
986# perform bounds checking.
987KBUILD_CFLAGS += $(call cc-option, -fstrict-flex-arrays=3)
988
989#Currently, disable -Wstringop-overflow for GCC 11, globally.
990KBUILD_CFLAGS-$(CONFIG_CC_NO_STRINGOP_OVERFLOW) += $(call cc-option, -Wno-stringop-overflow)
991KBUILD_CFLAGS-$(CONFIG_CC_STRINGOP_OVERFLOW) += $(call cc-option, -Wstringop-overflow)
992
993# disable invalid "can't wrap" optimizations for signed / pointers
994KBUILD_CFLAGS += -fno-strict-overflow
995
996# Make sure -fstack-check isn't enabled (like gentoo apparently did)
997KBUILD_CFLAGS += -fno-stack-check
998
999# conserve stack if available
1000ifdef CONFIG_CC_IS_GCC
1001KBUILD_CFLAGS += -fconserve-stack
1002endif
1003
1004# change __FILE__ to the relative path from the srctree
1005KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
1006
1007# include additional Makefiles when needed
1008include-y := scripts/Makefile.extrawarn
1009include-$(CONFIG_DEBUG_INFO) += scripts/Makefile.debug
1010include-$(CONFIG_DEBUG_INFO_BTF)+= scripts/Makefile.btf
1011include-$(CONFIG_KASAN) += scripts/Makefile.kasan
1012include-$(CONFIG_KCSAN) += scripts/Makefile.kcsan
1013include-$(CONFIG_KMSAN) += scripts/Makefile.kmsan
1014include-$(CONFIG_UBSAN) += scripts/Makefile.ubsan
1015include-$(CONFIG_KCOV) += scripts/Makefile.kcov
1016include-$(CONFIG_RANDSTRUCT) += scripts/Makefile.randstruct
1017include-$(CONFIG_GCC_PLUGINS) += scripts/Makefile.gcc-plugins
1018
1019include $(addprefix $(srctree)/, $(include-y))
1020
1021# scripts/Makefile.gcc-plugins is intentionally included last.
1022# Do not add $(call cc-option,...) below this line. When you build the kernel
1023# from the clean source tree, the GCC plugins do not exist at this point.
1024
1025# Add user supplied CPPFLAGS, AFLAGS, CFLAGS and RUSTFLAGS as the last assignments
1026KBUILD_CPPFLAGS += $(KCPPFLAGS)
1027KBUILD_AFLAGS += $(KAFLAGS)
1028KBUILD_CFLAGS += $(KCFLAGS)
1029KBUILD_RUSTFLAGS += $(KRUSTFLAGS)
1030
1031KBUILD_LDFLAGS_MODULE += --build-id=sha1
1032LDFLAGS_vmlinux += --build-id=sha1
1033
1034KBUILD_LDFLAGS += -z noexecstack
1035ifeq ($(CONFIG_LD_IS_BFD),y)
1036KBUILD_LDFLAGS += $(call ld-option,--no-warn-rwx-segments)
1037endif
1038
1039ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1040LDFLAGS_vmlinux += -X
1041endif
1042
1043ifeq ($(CONFIG_RELR),y)
1044# ld.lld before 15 did not support -z pack-relative-relocs.
1045LDFLAGS_vmlinux += $(call ld-option,--pack-dyn-relocs=relr,-z pack-relative-relocs)
1046endif
1047
1048# We never want expected sections to be placed heuristically by the
1049# linker. All sections should be explicitly named in the linker script.
1050ifdef CONFIG_LD_ORPHAN_WARN
1051LDFLAGS_vmlinux += --orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL)
1052endif
1053
1054# Align the bit size of userspace programs with the kernel
1055KBUILD_USERCFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1056KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1057
1058# make the checker run with the right architecture
1059CHECKFLAGS += --arch=$(ARCH)
1060
1061# insure the checker run with the right endianness
1062CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1063
1064# the checker needs the correct machine size
1065CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1066
1067# Default kernel image to build when no specific target is given.
1068# KBUILD_IMAGE may be overruled on the command line or
1069# set in the environment
1070# Also any assignments in arch/$(ARCH)/Makefile take precedence over
1071# this default value
1072export KBUILD_IMAGE ?= vmlinux
1073
1074#
1075# INSTALL_PATH specifies where to place the updated kernel and system map
1076# images. Default is /boot, but you can set it to other values
1077export INSTALL_PATH ?= /boot
1078
1079#
1080# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1081# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1082# an argument if needed. Otherwise it defaults to the kernel install path
1083#
1084export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1085
1086#
1087# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1088# relocations required by build roots. This is not defined in the
1089# makefile but the argument can be passed to make if needed.
1090#
1091
1092MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1093export MODLIB
1094
1095PHONY += prepare0
1096
1097export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
1098export MODORDER := $(extmod_prefix)modules.order
1099export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
1100
1101ifeq ($(KBUILD_EXTMOD),)
1102
1103build-dir := .
1104clean-dirs := $(sort . Documentation \
1105 $(patsubst %/,%,$(filter %/, $(core-) \
1106 $(drivers-) $(libs-))))
1107
1108export ARCH_CORE := $(core-y)
1109export ARCH_LIB := $(filter %/, $(libs-y))
1110export ARCH_DRIVERS := $(drivers-y) $(drivers-m)
1111# Externally visible symbols (used by link-vmlinux.sh)
1112
1113KBUILD_VMLINUX_OBJS := ./built-in.a
1114ifdef CONFIG_MODULES
1115KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1116KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1117else
1118KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1119endif
1120
1121export KBUILD_VMLINUX_LIBS
1122export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
1123
1124ifdef CONFIG_TRIM_UNUSED_KSYMS
1125# For the kernel to actually contain only the needed exported symbols,
1126# we have to build modules as well to determine what those symbols are.
1127KBUILD_MODULES := 1
1128endif
1129
1130# '$(AR) mPi' needs 'T' to workaround the bug of llvm-ar <= 14
1131quiet_cmd_ar_vmlinux.a = AR $@
1132 cmd_ar_vmlinux.a = \
1133 rm -f $@; \
1134 $(AR) cDPrST $@ $(KBUILD_VMLINUX_OBJS); \
1135 $(AR) mPiT $$($(AR) t $@ | sed -n 1p) $@ $$($(AR) t $@ | grep -F -f $(srctree)/scripts/head-object-list.txt)
1136
1137targets += vmlinux.a
1138vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt FORCE
1139 $(call if_changed,ar_vmlinux.a)
1140
1141PHONY += vmlinux_o
1142vmlinux_o: vmlinux.a $(KBUILD_VMLINUX_LIBS)
1143 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o
1144
1145vmlinux.o modules.builtin.modinfo modules.builtin: vmlinux_o
1146 @:
1147
1148PHONY += vmlinux
1149# LDFLAGS_vmlinux in the top Makefile defines linker flags for the top vmlinux,
1150# not for decompressors. LDFLAGS_vmlinux in arch/*/boot/compressed/Makefile is
1151# unrelated; the decompressors just happen to have the same base name,
1152# arch/*/boot/compressed/vmlinux.
1153# Export LDFLAGS_vmlinux only to scripts/Makefile.vmlinux.
1154#
1155# _LDFLAGS_vmlinux is a workaround for the 'private export' bug:
1156# https://savannah.gnu.org/bugs/?61463
1157# For Make > 4.4, the following simple code will work:
1158# vmlinux: private export LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1159vmlinux: private _LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
1160vmlinux: export LDFLAGS_vmlinux = $(_LDFLAGS_vmlinux)
1161vmlinux: __KEEPMAKEFILEO__C.o $(KBUILD_LDS) modpost
1162 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux
1163
1164# The actual objects are generated when descending,
1165# make sure no implicit rule kicks in
1166$(sort $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)): . ;
1167
1168ifeq ($(origin KERNELRELEASE),file)
1169filechk_kernel.release = $(srctree)/scripts/setlocalversion $(srctree)
1170else
1171filechk_kernel.release = echo $(KERNELRELEASE)
1172endif
1173
1174# Store (new) KERNELRELEASE string in include/config/kernel.release
1175include/config/kernel.release: FORCE
1176 $(call filechk,kernel.release)
1177
1178# Additional helpers built in scripts
1179# Carefully list dependencies so we do not try to build scripts twice
1180# in parallel
1181PHONY += scripts
1182scripts: scripts_basic scripts_dtc
1183 $(Q)$(MAKE) $(build)=$(@)
1184
1185# Things we need to do before we recursively start building the kernel
1186# or the modules are listed in "prepare".
1187# A multi level approach is used. prepareN is processed before prepareN-1.
1188# archprepare is used in arch Makefiles and when processed asm symlink,
1189# version.h and scripts_basic is processed / created.
1190
1191PHONY += prepare archprepare
1192
1193archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1194 asm-generic $(version_h) include/generated/utsrelease.h \
1195 include/generated/compile.h include/generated/autoconf.h remove-stale-files
1196
1197prepare0: archprepare
1198 $(Q)$(MAKE) $(build)=scripts/mod
1199 $(Q)$(MAKE) $(build)=. prepare
1200
1201# All the preparing..
1202prepare: prepare0
1203ifdef CONFIG_RUST
1204 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh
1205 $(Q)$(MAKE) $(build)=rust
1206endif
1207
1208PHONY += remove-stale-files
1209remove-stale-files:
1210 $(Q)$(srctree)/scripts/remove-stale-files
1211
1212# Support for using generic headers in asm-generic
1213asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1214
1215PHONY += asm-generic uapi-asm-generic
1216asm-generic: uapi-asm-generic
1217 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1218 generic=include/asm-generic
1219uapi-asm-generic:
1220 $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1221 generic=include/uapi/asm-generic
1222
1223# Generate some files
1224# ---------------------------------------------------------------------------
1225
1226# KERNELRELEASE can change from a few different places, meaning version.h
1227# needs to be updated, so this check is forced on all builds
1228
1229uts_len := 64
1230define filechk_utsrelease.h
1231 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1232 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1233 exit 1; \
1234 fi; \
1235 echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1236endef
1237
1238define filechk_version.h
1239 if [ $(SUBLEVEL) -gt 255 ]; then \
1240 echo \#define LINUX_VERSION_CODE $(shell \
1241 expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1242 else \
1243 echo \#define LINUX_VERSION_CODE $(shell \
1244 expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1245 fi; \
1246 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + \
1247 ((c) > 255 ? 255 : (c)))'; \
1248 echo \#define LINUX_VERSION_MAJOR $(VERSION); \
1249 echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL); \
1250 echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1251endef
1252
1253$(version_h): PATCHLEVEL := $(or $(PATCHLEVEL), 0)
1254$(version_h): SUBLEVEL := $(or $(SUBLEVEL), 0)
1255$(version_h): FORCE
1256 $(call filechk,version.h)
1257
1258include/generated/utsrelease.h: include/config/kernel.release FORCE
1259 $(call filechk,utsrelease.h)
1260
1261filechk_compile.h = $(srctree)/scripts/mkcompile_h \
1262 "$(UTS_MACHINE)" "$(CONFIG_CC_VERSION_TEXT)" "$(LD)"
1263
1264include/generated/compile.h: FORCE
1265 $(call filechk,compile.h)
1266
1267PHONY += headerdep
1268headerdep:
1269 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1270 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1271
1272# ---------------------------------------------------------------------------
1273# Kernel headers
1274
1275#Default location for installed headers
1276export INSTALL_HDR_PATH = $(objtree)/usr
1277
1278quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1279 cmd_headers_install = \
1280 mkdir -p $(INSTALL_HDR_PATH); \
1281 rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1282 usr/include $(INSTALL_HDR_PATH)
1283
1284PHONY += headers_install
1285headers_install: headers
1286 $(call cmd,headers_install)
1287
1288PHONY += archheaders archscripts
1289
1290hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1291
1292PHONY += headers
1293headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1294 $(if $(filter um, $(SRCARCH)), $(error Headers not exportable for UML))
1295 $(Q)$(MAKE) $(hdr-inst)=include/uapi
1296 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1297
1298ifdef CONFIG_HEADERS_INSTALL
1299prepare: headers
1300endif
1301
1302PHONY += scripts_unifdef
1303scripts_unifdef: scripts_basic
1304 $(Q)$(MAKE) $(build)=scripts scripts/unifdef
1305
1306# ---------------------------------------------------------------------------
1307# Install
1308
1309# Many distributions have the custom install script, /sbin/installkernel.
1310# If DKMS is installed, 'make install' will eventually recurse back
1311# to this Makefile to build and install external modules.
1312# Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
1313
1314quiet_cmd_install = INSTALL $(INSTALL_PATH)
1315 cmd_install = unset sub_make_done; $(srctree)/scripts/install.sh
1316
1317# ---------------------------------------------------------------------------
1318# vDSO install
1319
1320PHONY += vdso_install
1321vdso_install: export INSTALL_FILES = $(vdso-install-y)
1322vdso_install:
1323 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vdsoinst
1324
1325# ---------------------------------------------------------------------------
1326# Tools
1327
1328ifdef CONFIG_OBJTOOL
1329prepare: tools/objtool
1330endif
1331
1332ifdef CONFIG_BPF
1333ifdef CONFIG_DEBUG_INFO_BTF
1334prepare: tools/bpf/resolve_btfids
1335endif
1336endif
1337
1338PHONY += resolve_btfids_clean
1339
1340resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1341
1342# tools/bpf/resolve_btfids directory might not exist
1343# in output directory, skip its clean in that case
1344resolve_btfids_clean:
1345ifneq ($(wildcard $(resolve_btfids_O)),)
1346 $(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1347endif
1348
1349# Clear a bunch of variables before executing the submake
1350ifeq ($(quiet),silent_)
1351tools_silent=s
1352endif
1353
1354tools/: FORCE
1355 $(Q)mkdir -p $(objtree)/tools
1356 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1357
1358tools/%: FORCE
1359 $(Q)mkdir -p $(objtree)/tools
1360 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1361
1362# ---------------------------------------------------------------------------
1363# Kernel selftest
1364
1365PHONY += kselftest
1366kselftest: headers
1367 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1368
1369kselftest-%: headers FORCE
1370 $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1371
1372PHONY += kselftest-merge
1373kselftest-merge:
1374 $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1375 $(Q)find $(srctree)/tools/testing/selftests -name config -o -name config.$(UTS_MACHINE) | \
1376 xargs $(srctree)/scripts/kconfig/merge_config.sh -y -m $(objtree)/.config
1377 $(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1378
1379# ---------------------------------------------------------------------------
1380# Devicetree files
1381
1382ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1383dtstree := arch/$(SRCARCH)/boot/dts
1384endif
1385
1386ifneq ($(dtstree),)
1387
1388%.dtb: dtbs_prepare
1389 $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1390
1391%.dtbo: dtbs_prepare
1392 $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1393
1394PHONY += dtbs dtbs_prepare dtbs_install dtbs_check
1395dtbs: dtbs_prepare
1396 $(Q)$(MAKE) $(build)=$(dtstree)
1397
1398# include/config/kernel.release is actually needed when installing DTBs because
1399# INSTALL_DTBS_PATH contains $(KERNELRELEASE). However, we do not want to make
1400# dtbs_install depend on it as dtbs_install may run as root.
1401dtbs_prepare: include/config/kernel.release scripts_dtc
1402
1403ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1404export CHECK_DTBS=y
1405endif
1406
1407ifneq ($(CHECK_DTBS),)
1408dtbs_prepare: dt_binding_check
1409endif
1410
1411dtbs_check: dtbs
1412
1413dtbs_install:
1414 $(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1415
1416ifdef CONFIG_OF_EARLY_FLATTREE
1417all: dtbs
1418endif
1419
1420endif
1421
1422PHONY += scripts_dtc
1423scripts_dtc: scripts_basic
1424 $(Q)$(MAKE) $(build)=scripts/dtc
1425
1426ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1427export CHECK_DT_BINDING=y
1428endif
1429
1430PHONY += dt_binding_check
1431dt_binding_check: scripts_dtc
1432 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1433
1434PHONY += dt_compatible_check
1435dt_compatible_check: dt_binding_check
1436 $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings $@
1437
1438# ---------------------------------------------------------------------------
1439# Modules
1440
1441ifdef CONFIG_MODULES
1442
1443# By default, build modules as well
1444
1445all: modules
1446
1447# When we're building modules with modversions, we need to consider
1448# the built-in objects during the descend as well, in order to
1449# make sure the checksums are up to date before we record them.
1450ifdef CONFIG_MODVERSIONS
1451 KBUILD_BUILTIN := 1
1452endif
1453
1454# Build modules
1455#
1456
1457# *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFO_BTF_MODULES
1458# is an exception.
1459ifdef CONFIG_DEBUG_INFO_BTF_MODULES
1460KBUILD_BUILTIN := 1
1461modules: vmlinux
1462endif
1463
1464modules: modules_prepare
1465
1466# Target to prepare building external modules
1467modules_prepare: prepare
1468 $(Q)$(MAKE) $(build)=scripts scripts/module.lds
1469
1470endif # CONFIG_MODULES
1471
1472###
1473# Cleaning is done on three levels.
1474# make clean Delete most generated files
1475# Leave enough to build external modules
1476# make mrproper Delete the current configuration, and all generated files
1477# make distclean Remove editor backup files, patch leftover files and the like
1478
1479# Directories & files removed with 'make clean'
1480CLEAN_FILES += vmlinux.symvers modules-only.symvers \
1481 modules.builtin modules.builtin.modinfo modules.nsdeps \
1482 compile_commands.json .thinlto-cache rust/test \
1483 rust-project.json .vmlinux.objs .vmlinux.export.c
1484
1485# Directories & files removed with 'make mrproper'
1486MRPROPER_FILES += include/config include/generated \
1487 arch/$(SRCARCH)/include/generated .objdiff \
1488 debian snap tar-install \
1489 .config .config.old .version \
1490 Module.symvers \
1491 certs/signing_key.pem \
1492 certs/x509.genkey \
1493 vmlinux-gdb.py \
1494 rpmbuild \
1495 rust/libmacros.so
1496
1497# clean - Delete most, but leave enough to build external modules
1498#
1499clean: rm-files := $(CLEAN_FILES)
1500
1501PHONY += archclean vmlinuxclean
1502
1503vmlinuxclean:
1504 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1505 $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1506
1507clean: archclean vmlinuxclean resolve_btfids_clean
1508
1509# mrproper - Delete all generated files, including .config
1510#
1511mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1512mrproper-dirs := $(addprefix _mrproper_,scripts)
1513
1514PHONY += $(mrproper-dirs) mrproper
1515$(mrproper-dirs):
1516 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1517
1518mrproper: clean $(mrproper-dirs)
1519 $(call cmd,rmfiles)
1520 @find . $(RCS_FIND_IGNORE) \
1521 \( -name '*.rmeta' \) \
1522 -type f -print | xargs rm -f
1523
1524# distclean
1525#
1526PHONY += distclean
1527
1528distclean: mrproper
1529 @find . $(RCS_FIND_IGNORE) \
1530 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1531 -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1532 -o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1533 -o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1534 -type f -print | xargs rm -f
1535
1536
1537# Packaging of the kernel to various formats
1538# ---------------------------------------------------------------------------
1539
1540%src-pkg: FORCE
1541 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1542%pkg: include/config/kernel.release FORCE
1543 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1544
1545# Brief documentation of the typical targets used
1546# ---------------------------------------------------------------------------
1547
1548boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1549boards := $(sort $(notdir $(boards)))
1550board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1551board-dirs := $(sort $(notdir $(board-dirs:/=)))
1552
1553PHONY += help
1554help:
1555 @echo 'Cleaning targets:'
1556 @echo ' clean - Remove most generated files but keep the config and'
1557 @echo ' enough build support to build external modules'
1558 @echo ' mrproper - Remove all generated files + config + various backup files'
1559 @echo ' distclean - mrproper + remove editor backup and patch files'
1560 @echo ''
1561 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1562 @echo ''
1563 @echo 'Other generic targets:'
1564 @echo ' all - Build all targets marked with [*]'
1565 @echo '* vmlinux - Build the bare kernel'
1566 @echo '* modules - Build all modules'
1567 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1568 @echo ' vdso_install - Install unstripped vdso to INSTALL_MOD_PATH (default: /)'
1569 @echo ' dir/ - Build all files in dir and below'
1570 @echo ' dir/file.[ois] - Build specified target only'
1571 @echo ' dir/file.ll - Build the LLVM assembly file'
1572 @echo ' (requires compiler support for LLVM assembly generation)'
1573 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1574 @echo ' (requires a recent binutils and recent build (System.map))'
1575 @echo ' dir/file.ko - Build module including final link'
1576 @echo ' modules_prepare - Set up for building external modules'
1577 @echo ' tags/TAGS - Generate tags file for editors'
1578 @echo ' cscope - Generate cscope index'
1579 @echo ' gtags - Generate GNU GLOBAL index'
1580 @echo ' kernelrelease - Output the release version string (use with make -s)'
1581 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1582 @echo ' image_name - Output the image name (use with make -s)'
1583 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1584 echo ' (default: $(INSTALL_HDR_PATH))'; \
1585 echo ''
1586 @echo 'Static analysers:'
1587 @echo ' checkstack - Generate a list of stack hogs and consider all functions'
1588 @echo ' with a stack size larger than MINSTACKSIZE (default: 100)'
1589 @echo ' versioncheck - Sanity check on version.h usage'
1590 @echo ' includecheck - Check for duplicate included header files'
1591 @echo ' export_report - List the usages of all exported symbols'
1592 @echo ' headerdep - Detect inclusion cycles in headers'
1593 @echo ' coccicheck - Check with Coccinelle'
1594 @echo ' clang-analyzer - Check with clang static analyzer'
1595 @echo ' clang-tidy - Check with clang-tidy'
1596 @echo ''
1597 @echo 'Tools:'
1598 @echo ' nsdeps - Generate missing symbol namespace dependencies'
1599 @echo ''
1600 @echo 'Kernel selftest:'
1601 @echo ' kselftest - Build and run kernel selftest'
1602 @echo ' Build, install, and boot kernel before'
1603 @echo ' running kselftest on it'
1604 @echo ' Run as root for full coverage'
1605 @echo ' kselftest-all - Build kernel selftest'
1606 @echo ' kselftest-install - Build and install kernel selftest'
1607 @echo ' kselftest-clean - Remove all generated kselftest files'
1608 @echo ' kselftest-merge - Merge all the config dependencies of'
1609 @echo ' kselftest to existing .config.'
1610 @echo ''
1611 @echo 'Rust targets:'
1612 @echo ' rustavailable - Checks whether the Rust toolchain is'
1613 @echo ' available and, if not, explains why.'
1614 @echo ' rustfmt - Reformat all the Rust code in the kernel'
1615 @echo ' rustfmtcheck - Checks if all the Rust code in the kernel'
1616 @echo ' is formatted, printing a diff otherwise.'
1617 @echo ' rustdoc - Generate Rust documentation'
1618 @echo ' (requires kernel .config)'
1619 @echo ' rusttest - Runs the Rust tests'
1620 @echo ' (requires kernel .config; downloads external repos)'
1621 @echo ' rust-analyzer - Generate rust-project.json rust-analyzer support file'
1622 @echo ' (requires kernel .config)'
1623 @echo ' dir/file.[os] - Build specified target only'
1624 @echo ' dir/file.rsi - Build macro expanded source, similar to C preprocessing.'
1625 @echo ' Run with RUSTFMT=n to skip reformatting if needed.'
1626 @echo ' The output is not intended to be compilable.'
1627 @echo ' dir/file.ll - Build the LLVM assembly file'
1628 @echo ''
1629 @$(if $(dtstree), \
1630 echo 'Devicetree:'; \
1631 echo '* dtbs - Build device tree blobs for enabled boards'; \
1632 echo ' dtbs_install - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1633 echo ' dt_binding_check - Validate device tree binding documents'; \
1634 echo ' dtbs_check - Validate device tree source files';\
1635 echo '')
1636
1637 @echo 'Userspace tools targets:'
1638 @echo ' use "make tools/help"'
1639 @echo ' or "cd tools; make help"'
1640 @echo ''
1641 @echo 'Kernel packaging:'
1642 @$(MAKE) -f $(srctree)/scripts/Makefile.package help
1643 @echo ''
1644 @echo 'Documentation targets:'
1645 @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1646 @echo ''
1647 @echo 'Architecture-specific targets ($(SRCARCH)):'
1648 @$(or $(archhelp),\
1649 echo ' No architecture-specific help defined for $(SRCARCH)')
1650 @echo ''
1651 @$(if $(boards), \
1652 $(foreach b, $(boards), \
1653 printf " %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1654 echo '')
1655 @$(if $(board-dirs), \
1656 $(foreach b, $(board-dirs), \
1657 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1658 printf " %-16s - Show all of the above\\n" help-boards; \
1659 echo '')
1660
1661 @echo ' make V=n [targets] 1: verbose build'
1662 @echo ' 2: give reason for rebuild of target'
1663 @echo ' V=1 and V=2 can be combined with V=12'
1664 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1665 @echo ' make C=1 [targets] Check re-compiled c source with $$CHECK'
1666 @echo ' (sparse by default)'
1667 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1668 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1669 @echo ' make W=n [targets] Enable extra build checks, n=1,2,3,c,e where'
1670 @echo ' 1: warnings which may be relevant and do not occur too often'
1671 @echo ' 2: warnings which occur quite often but may still be relevant'
1672 @echo ' 3: more obscure warnings, can most likely be ignored'
1673 @echo ' c: extra checks in the configuration stage (Kconfig)'
1674 @echo ' e: warnings are being treated as errors'
1675 @echo ' Multiple levels can be combined with W=12 or W=123'
1676 @$(if $(dtstree), \
1677 echo ' make CHECK_DTBS=1 [targets] Check all generated dtb files against schema'; \
1678 echo ' This can be applied both to "dtbs" and to individual "foo.dtb" targets' ; \
1679 )
1680 @echo ''
1681 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1682 @echo 'For further info see the ./README file'
1683
1684
1685help-board-dirs := $(addprefix help-,$(board-dirs))
1686
1687help-boards: $(help-board-dirs)
1688
1689boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1690
1691$(help-board-dirs): help-%:
1692 @echo 'Architecture-specific targets ($(SRCARCH) $*):'
1693 @$(if $(boards-per-dir), \
1694 $(foreach b, $(boards-per-dir), \
1695 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1696 echo '')
1697
1698
1699# Documentation targets
1700# ---------------------------------------------------------------------------
1701DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1702 linkcheckdocs dochelp refcheckdocs texinfodocs infodocs
1703PHONY += $(DOC_TARGETS)
1704$(DOC_TARGETS):
1705 $(Q)$(MAKE) $(build)=Documentation $@
1706
1707
1708# Rust targets
1709# ---------------------------------------------------------------------------
1710
1711# "Is Rust available?" target
1712PHONY += rustavailable
1713rustavailable:
1714 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh && echo "Rust is available!"
1715
1716# Documentation target
1717#
1718# Using the singular to avoid running afoul of `no-dot-config-targets`.
1719PHONY += rustdoc
1720rustdoc: prepare
1721 $(Q)$(MAKE) $(build)=rust $@
1722
1723# Testing target
1724PHONY += rusttest
1725rusttest: prepare
1726 $(Q)$(MAKE) $(build)=rust $@
1727
1728# Formatting targets
1729PHONY += rustfmt rustfmtcheck
1730
1731# We skip `rust/alloc` since we want to minimize the diff w.r.t. upstream.
1732#
1733# We match using absolute paths since `find` does not resolve them
1734# when matching, which is a problem when e.g. `srctree` is `..`.
1735# We `grep` afterwards in order to remove the directory entry itself.
1736rustfmt:
1737 $(Q)find $(abs_srctree) -type f -name '*.rs' \
1738 -o -path $(abs_srctree)/rust/alloc -prune \
1739 -o -path $(abs_objtree)/rust/test -prune \
1740 | grep -Fv $(abs_srctree)/rust/alloc \
1741 | grep -Fv $(abs_objtree)/rust/test \
1742 | grep -Fv generated \
1743 | xargs $(RUSTFMT) $(rustfmt_flags)
1744
1745rustfmtcheck: rustfmt_flags = --check
1746rustfmtcheck: rustfmt
1747
1748# Misc
1749# ---------------------------------------------------------------------------
1750
1751PHONY += misc-check
1752misc-check:
1753 $(Q)$(srctree)/scripts/misc-check
1754
1755all: misc-check
1756
1757PHONY += scripts_gdb
1758scripts_gdb: prepare0
1759 $(Q)$(MAKE) $(build)=scripts/gdb
1760 $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1761
1762ifdef CONFIG_GDB_SCRIPTS
1763all: scripts_gdb
1764endif
1765
1766else # KBUILD_EXTMOD
1767
1768filechk_kernel.release = echo $(KERNELRELEASE)
1769
1770###
1771# External module support.
1772# When building external modules the kernel used as basis is considered
1773# read-only, and no consistency checks are made and the make
1774# system is not used on the basis kernel. If updates are required
1775# in the basis kernel ordinary make commands (without M=...) must be used.
1776
1777# We are always building only modules.
1778KBUILD_BUILTIN :=
1779KBUILD_MODULES := 1
1780
1781build-dir := $(KBUILD_EXTMOD)
1782
1783compile_commands.json: $(extmod_prefix)compile_commands.json
1784PHONY += compile_commands.json
1785
1786clean-dirs := $(KBUILD_EXTMOD)
1787clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1788 $(KBUILD_EXTMOD)/compile_commands.json $(KBUILD_EXTMOD)/.thinlto-cache
1789
1790PHONY += prepare
1791# now expand this into a simple variable to reduce the cost of shell evaluations
1792prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT)
1793prepare:
1794 @if [ "$(CC_VERSION_TEXT)" != "$(CONFIG_CC_VERSION_TEXT)" ]; then \
1795 echo >&2 "warning: the compiler differs from the one used to build the kernel"; \
1796 echo >&2 " The kernel was built by: $(CONFIG_CC_VERSION_TEXT)"; \
1797 echo >&2 " You are using: $(CC_VERSION_TEXT)"; \
1798 fi
1799
1800PHONY += help
1801help:
1802 @echo ' Building external modules.'
1803 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1804 @echo ''
1805 @echo ' modules - default target, build the module(s)'
1806 @echo ' modules_install - install the module'
1807 @echo ' clean - remove generated files in module directory only'
1808 @echo ' rust-analyzer - generate rust-project.json rust-analyzer support file'
1809 @echo ''
1810
1811ifndef CONFIG_MODULES
1812modules modules_install: __external_modules_error
1813__external_modules_error:
1814 @echo >&2 '***'
1815 @echo >&2 '*** The present kernel disabled CONFIG_MODULES.'
1816 @echo >&2 '*** You cannot build or install external modules.'
1817 @echo >&2 '***'
1818 @false
1819endif
1820
1821endif # KBUILD_EXTMOD
1822
1823# ---------------------------------------------------------------------------
1824# Modules
1825
1826PHONY += modules modules_install modules_sign modules_prepare
1827
1828modules_install:
1829 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst \
1830 sign-only=$(if $(filter modules_install,$(MAKECMDGOALS)),,y)
1831
1832ifeq ($(CONFIG_MODULE_SIG),y)
1833# modules_sign is a subset of modules_install.
1834# 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1835modules_sign: modules_install
1836 @:
1837else
1838modules_sign:
1839 @echo >&2 '***'
1840 @echo >&2 '*** CONFIG_MODULE_SIG is disabled. You cannot sign modules.'
1841 @echo >&2 '***'
1842 @false
1843endif
1844
1845ifdef CONFIG_MODULES
1846
1847$(MODORDER): $(build-dir)
1848 @:
1849
1850# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
1851# This is solely useful to speed up test compiles.
1852modules: modpost
1853ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1854 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1855endif
1856
1857PHONY += modules_check
1858modules_check: $(MODORDER)
1859 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1860
1861else # CONFIG_MODULES
1862
1863modules:
1864 @:
1865
1866KBUILD_MODULES :=
1867
1868endif # CONFIG_MODULES
1869
1870PHONY += modpost
1871modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \
1872 $(if $(KBUILD_MODULES), modules_check)
1873 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1874
1875# Single targets
1876# ---------------------------------------------------------------------------
1877# To build individual files in subdirectories, you can do like this:
1878#
1879# make foo/bar/baz.s
1880#
1881# The supported suffixes for single-target are listed in 'single-targets'
1882#
1883# To build only under specific subdirectories, you can do like this:
1884#
1885# make foo/bar/baz/
1886
1887ifdef single-build
1888
1889# .ko is special because modpost is needed
1890single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1891single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \
1892 $(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko)))
1893
1894$(single-ko): single_modules
1895 @:
1896$(single-no-ko): $(build-dir)
1897 @:
1898
1899# Remove MODORDER when done because it is not the real one.
1900PHONY += single_modules
1901single_modules: $(single-no-ko) modules_prepare
1902 $(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$(m:%.ko=%.o);) } > $(MODORDER)
1903 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1904ifneq ($(KBUILD_MODPOST_NOFINAL),1)
1905 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
1906endif
1907 $(Q)rm -f $(MODORDER)
1908
1909single-goals := $(addprefix $(build-dir)/, $(single-no-ko))
1910
1911KBUILD_MODULES := 1
1912
1913endif
1914
1915# Preset locale variables to speed up the build process. Limit locale
1916# tweaks to this spot to avoid wrong language settings when running
1917# make menuconfig etc.
1918# Error messages still appears in the original language
1919PHONY += $(build-dir)
1920$(build-dir): prepare
1921 $(Q)$(MAKE) $(build)=$@ need-builtin=1 need-modorder=1 $(single-goals)
1922
1923clean-dirs := $(addprefix _clean_, $(clean-dirs))
1924PHONY += $(clean-dirs) clean
1925$(clean-dirs):
1926 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1927
1928clean: $(clean-dirs)
1929 $(call cmd,rmfiles)
1930 @find $(or $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1931 \( -name '*.[aios]' -o -name '*.rsi' -o -name '*.ko' -o -name '.*.cmd' \
1932 -o -name '*.ko.*' \
1933 -o -name '*.dtb' -o -name '*.dtbo' \
1934 -o -name '*.dtb.S' -o -name '*.dtbo.S' \
1935 -o -name '*.dt.yaml' \
1936 -o -name '*.dwo' -o -name '*.lst' \
1937 -o -name '*.su' -o -name '*.mod' \
1938 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1939 -o -name '*.lex.c' -o -name '*.tab.[ch]' \
1940 -o -name '*.asn1.[ch]' \
1941 -o -name '*.symtypes' -o -name 'modules.order' \
1942 -o -name '*.c.[012]*.*' \
1943 -o -name '*.ll' \
1944 -o -name '*.gcno' \
1945 -o -name '*.*.symversions' \) -type f -print \
1946 -o -name '.tmp_*' -print \
1947 | xargs rm -rf
1948
1949# Generate tags for editors
1950# ---------------------------------------------------------------------------
1951quiet_cmd_tags = GEN $@
1952 cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1953
1954tags TAGS cscope gtags: FORCE
1955 $(call cmd,tags)
1956
1957# IDE support targets
1958PHONY += rust-analyzer
1959rust-analyzer:
1960 $(Q)$(MAKE) $(build)=rust $@
1961
1962# Script to generate missing namespace dependencies
1963# ---------------------------------------------------------------------------
1964
1965PHONY += nsdeps
1966nsdeps: export KBUILD_NSDEPS=1
1967nsdeps: modules
1968 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1969
1970# Clang Tooling
1971# ---------------------------------------------------------------------------
1972
1973quiet_cmd_gen_compile_commands = GEN $@
1974 cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
1975
1976$(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
1977 $(if $(KBUILD_EXTMOD),, vmlinux.a $(KBUILD_VMLINUX_LIBS)) \
1978 $(if $(CONFIG_MODULES), $(MODORDER)) FORCE
1979 $(call if_changed,gen_compile_commands)
1980
1981targets += $(extmod_prefix)compile_commands.json
1982
1983PHONY += clang-tidy clang-analyzer
1984
1985ifdef CONFIG_CC_IS_CLANG
1986quiet_cmd_clang_tools = CHECK $<
1987 cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
1988
1989clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
1990 $(call cmd,clang_tools)
1991else
1992clang-tidy clang-analyzer:
1993 @echo "$@ requires CC=clang" >&2
1994 @false
1995endif
1996
1997# Scripts to check various things for consistency
1998# ---------------------------------------------------------------------------
1999
2000PHONY += includecheck versioncheck coccicheck export_report
2001
2002includecheck:
2003 find $(srctree)/* $(RCS_FIND_IGNORE) \
2004 -name '*.[hcS]' -type f -print | sort \
2005 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
2006
2007versioncheck:
2008 find $(srctree)/* $(RCS_FIND_IGNORE) \
2009 -name '*.[hcS]' -type f -print | sort \
2010 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
2011
2012coccicheck:
2013 $(Q)$(BASH) $(srctree)/scripts/$@
2014
2015export_report:
2016 $(PERL) $(srctree)/scripts/export_report.pl
2017
2018PHONY += checkstack kernelrelease kernelversion image_name
2019
2020# UML needs a little special treatment here. It wants to use the host
2021# toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
2022# else wants $(ARCH), including people doing cross-builds, which means
2023# that $(SUBARCH) doesn't work here.
2024ifeq ($(ARCH), um)
2025CHECKSTACK_ARCH := $(SUBARCH)
2026else
2027CHECKSTACK_ARCH := $(ARCH)
2028endif
2029MINSTACKSIZE ?= 100
2030checkstack:
2031 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
2032 $(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH) $(MINSTACKSIZE)
2033
2034kernelrelease:
2035 @$(filechk_kernel.release)
2036
2037kernelversion:
2038 @echo $(KERNELVERSION)
2039
2040image_name:
2041 @echo $(KBUILD_IMAGE)
2042
2043PHONY += run-command
2044run-command:
2045 $(Q)$(KBUILD_RUN_COMMAND)
2046
2047quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
2048 cmd_rmfiles = rm -rf $(rm-files)
2049
2050# read saved command lines for existing targets
2051existing-targets := $(wildcard $(sort $(targets)))
2052
2053-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
2054
2055endif # config-build
2056endif # mixed-build
2057endif # need-sub-make
2058
2059PHONY += FORCE
2060FORCE:
2061
2062# Declare the contents of the PHONY variable as phony. We keep that
2063# information in a variable so we can use it in if_changed and friends.
2064.PHONY: $(PHONY)
1VERSION = 4
2PATCHLEVEL = 6
3SUBLEVEL = 0
4EXTRAVERSION =
5NAME = Charred Weasel
6
7# *DOCUMENTATION*
8# To see a list of typical targets execute "make help"
9# More info can be located in ./README
10# Comments in this file are targeted only to the developer, do not
11# expect to learn how to build the kernel reading this file.
12
13# o Do not use make's built-in rules and variables
14# (this increases performance and avoids hard-to-debug behaviour);
15# o Look for make include files relative to root of kernel src
16MAKEFLAGS += -rR --include-dir=$(CURDIR)
17
18# Avoid funny character set dependencies
19unexport LC_ALL
20LC_COLLATE=C
21LC_NUMERIC=C
22export LC_COLLATE LC_NUMERIC
23
24# Avoid interference with shell env settings
25unexport GREP_OPTIONS
26
27# We are using a recursive build, so we need to do a little thinking
28# to get the ordering right.
29#
30# Most importantly: sub-Makefiles should only ever modify files in
31# their own directory. If in some directory we have a dependency on
32# a file in another dir (which doesn't happen often, but it's often
33# unavoidable when linking the built-in.o targets which finally
34# turn into vmlinux), we will call a sub make in that other dir, and
35# after that we are sure that everything which is in that other dir
36# is now up to date.
37#
38# The only cases where we need to modify files which have global
39# effects are thus separated out and done before the recursive
40# descending is started. They are now explicitly listed as the
41# prepare rule.
42
43# Beautify output
44# ---------------------------------------------------------------------------
45#
46# Normally, we echo the whole command before executing it. By making
47# that echo $($(quiet)$(cmd)), we now have the possibility to set
48# $(quiet) to choose other forms of output instead, e.g.
49#
50# quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
51# cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
52#
53# If $(quiet) is empty, the whole command will be printed.
54# If it is set to "quiet_", only the short version will be printed.
55# If it is set to "silent_", nothing will be printed at all, since
56# the variable $(silent_cmd_cc_o_c) doesn't exist.
57#
58# A simple variant is to prefix commands with $(Q) - that's useful
59# for commands that shall be hidden in non-verbose mode.
60#
61# $(Q)ln $@ :<
62#
63# If KBUILD_VERBOSE equals 0 then the above command will be hidden.
64# If KBUILD_VERBOSE equals 1 then the above command is displayed.
65#
66# To put more focus on warnings, be less verbose as default
67# Use 'make V=1' to see the full commands
68
69ifeq ("$(origin V)", "command line")
70 KBUILD_VERBOSE = $(V)
71endif
72ifndef KBUILD_VERBOSE
73 KBUILD_VERBOSE = 0
74endif
75
76ifeq ($(KBUILD_VERBOSE),1)
77 quiet =
78 Q =
79else
80 quiet=quiet_
81 Q = @
82endif
83
84# If the user is running make -s (silent mode), suppress echoing of
85# commands
86
87ifneq ($(filter 4.%,$(MAKE_VERSION)),) # make-4
88ifneq ($(filter %s ,$(firstword x$(MAKEFLAGS))),)
89 quiet=silent_
90endif
91else # make-3.8x
92ifneq ($(filter s% -s%,$(MAKEFLAGS)),)
93 quiet=silent_
94endif
95endif
96
97export quiet Q KBUILD_VERBOSE
98
99# kbuild supports saving output files in a separate directory.
100# To locate output files in a separate directory two syntaxes are supported.
101# In both cases the working directory must be the root of the kernel src.
102# 1) O=
103# Use "make O=dir/to/store/output/files/"
104#
105# 2) Set KBUILD_OUTPUT
106# Set the environment variable KBUILD_OUTPUT to point to the directory
107# where the output files shall be placed.
108# export KBUILD_OUTPUT=dir/to/store/output/files/
109# make
110#
111# The O= assignment takes precedence over the KBUILD_OUTPUT environment
112# variable.
113
114# KBUILD_SRC is set on invocation of make in OBJ directory
115# KBUILD_SRC is not intended to be used by the regular user (for now)
116ifeq ($(KBUILD_SRC),)
117
118# OK, Make called in directory where kernel src resides
119# Do we want to locate output files in a separate directory?
120ifeq ("$(origin O)", "command line")
121 KBUILD_OUTPUT := $(O)
122endif
123
124# That's our default target when none is given on the command line
125PHONY := _all
126_all:
127
128# Cancel implicit rules on top Makefile
129$(CURDIR)/Makefile Makefile: ;
130
131ifneq ($(KBUILD_OUTPUT),)
132# Invoke a second make in the output directory, passing relevant variables
133# check that the output directory actually exists
134saved-output := $(KBUILD_OUTPUT)
135KBUILD_OUTPUT := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) \
136 && /bin/pwd)
137$(if $(KBUILD_OUTPUT),, \
138 $(error failed to create output directory "$(saved-output)"))
139
140PHONY += $(MAKECMDGOALS) sub-make
141
142$(filter-out _all sub-make $(CURDIR)/Makefile, $(MAKECMDGOALS)) _all: sub-make
143 @:
144
145sub-make: FORCE
146 $(Q)$(MAKE) -C $(KBUILD_OUTPUT) KBUILD_SRC=$(CURDIR) \
147 -f $(CURDIR)/Makefile $(filter-out _all sub-make,$(MAKECMDGOALS))
148
149# Leave processing to above invocation of make
150skip-makefile := 1
151endif # ifneq ($(KBUILD_OUTPUT),)
152endif # ifeq ($(KBUILD_SRC),)
153
154# We process the rest of the Makefile if this is the final invocation of make
155ifeq ($(skip-makefile),)
156
157# Do not print "Entering directory ...",
158# but we want to display it when entering to the output directory
159# so that IDEs/editors are able to understand relative filenames.
160MAKEFLAGS += --no-print-directory
161
162# Call a source code checker (by default, "sparse") as part of the
163# C compilation.
164#
165# Use 'make C=1' to enable checking of only re-compiled files.
166# Use 'make C=2' to enable checking of *all* source files, regardless
167# of whether they are re-compiled or not.
168#
169# See the file "Documentation/sparse.txt" for more details, including
170# where to get the "sparse" utility.
171
172ifeq ("$(origin C)", "command line")
173 KBUILD_CHECKSRC = $(C)
174endif
175ifndef KBUILD_CHECKSRC
176 KBUILD_CHECKSRC = 0
177endif
178
179# Use make M=dir to specify directory of external module to build
180# Old syntax make ... SUBDIRS=$PWD is still supported
181# Setting the environment variable KBUILD_EXTMOD take precedence
182ifdef SUBDIRS
183 KBUILD_EXTMOD ?= $(SUBDIRS)
184endif
185
186ifeq ("$(origin M)", "command line")
187 KBUILD_EXTMOD := $(M)
188endif
189
190# If building an external module we do not care about the all: rule
191# but instead _all depend on modules
192PHONY += all
193ifeq ($(KBUILD_EXTMOD),)
194_all: all
195else
196_all: modules
197endif
198
199ifeq ($(KBUILD_SRC),)
200 # building in the source tree
201 srctree := .
202else
203 ifeq ($(KBUILD_SRC)/,$(dir $(CURDIR)))
204 # building in a subdirectory of the source tree
205 srctree := ..
206 else
207 srctree := $(KBUILD_SRC)
208 endif
209endif
210objtree := .
211src := $(srctree)
212obj := $(objtree)
213
214VPATH := $(srctree)$(if $(KBUILD_EXTMOD),:$(KBUILD_EXTMOD))
215
216export srctree objtree VPATH
217
218# SUBARCH tells the usermode build what the underlying arch is. That is set
219# first, and if a usermode build is happening, the "ARCH=um" on the command
220# line overrides the setting of ARCH below. If a native build is happening,
221# then ARCH is assigned, getting whatever value it gets normally, and
222# SUBARCH is subsequently ignored.
223
224SUBARCH := $(shell uname -m | sed -e s/i.86/x86/ -e s/x86_64/x86 \
225 -e s/sun4u/sparc64/ \
226 -e s/arm.*/arm/ -e s/sa110/arm/ \
227 -e s/s390x/s390/ -e s/parisc64/parisc/ \
228 -e s/ppc.*/powerpc/ -e s/mips.*/mips/ \
229 -e s/sh[234].*/sh/ -e s/aarch64.*/arm64/ )
230
231# Cross compiling and selecting different set of gcc/bin-utils
232# ---------------------------------------------------------------------------
233#
234# When performing cross compilation for other architectures ARCH shall be set
235# to the target architecture. (See arch/* for the possibilities).
236# ARCH can be set during invocation of make:
237# make ARCH=ia64
238# Another way is to have ARCH set in the environment.
239# The default ARCH is the host where make is executed.
240
241# CROSS_COMPILE specify the prefix used for all executables used
242# during compilation. Only gcc and related bin-utils executables
243# are prefixed with $(CROSS_COMPILE).
244# CROSS_COMPILE can be set on the command line
245# make CROSS_COMPILE=ia64-linux-
246# Alternatively CROSS_COMPILE can be set in the environment.
247# A third alternative is to store a setting in .config so that plain
248# "make" in the configured kernel build directory always uses that.
249# Default value for CROSS_COMPILE is not to prefix executables
250# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
251ARCH ?= $(SUBARCH)
252CROSS_COMPILE ?= $(CONFIG_CROSS_COMPILE:"%"=%)
253
254# Architecture as present in compile.h
255UTS_MACHINE := $(ARCH)
256SRCARCH := $(ARCH)
257
258# Additional ARCH settings for x86
259ifeq ($(ARCH),i386)
260 SRCARCH := x86
261endif
262ifeq ($(ARCH),x86_64)
263 SRCARCH := x86
264endif
265
266# Additional ARCH settings for sparc
267ifeq ($(ARCH),sparc32)
268 SRCARCH := sparc
269endif
270ifeq ($(ARCH),sparc64)
271 SRCARCH := sparc
272endif
273
274# Additional ARCH settings for sh
275ifeq ($(ARCH),sh64)
276 SRCARCH := sh
277endif
278
279# Additional ARCH settings for tile
280ifeq ($(ARCH),tilepro)
281 SRCARCH := tile
282endif
283ifeq ($(ARCH),tilegx)
284 SRCARCH := tile
285endif
286
287# Where to locate arch specific headers
288hdr-arch := $(SRCARCH)
289
290KCONFIG_CONFIG ?= .config
291export KCONFIG_CONFIG
292
293# SHELL used by kbuild
294CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
295 else if [ -x /bin/bash ]; then echo /bin/bash; \
296 else echo sh; fi ; fi)
297
298HOSTCC = gcc
299HOSTCXX = g++
300HOSTCFLAGS = -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 -fomit-frame-pointer -std=gnu89
301HOSTCXXFLAGS = -O2
302
303ifeq ($(shell $(HOSTCC) -v 2>&1 | grep -c "clang version"), 1)
304HOSTCFLAGS += -Wno-unused-value -Wno-unused-parameter \
305 -Wno-missing-field-initializers -fno-delete-null-pointer-checks
306endif
307
308# Decide whether to build built-in, modular, or both.
309# Normally, just do built-in.
310
311KBUILD_MODULES :=
312KBUILD_BUILTIN := 1
313
314# If we have only "make modules", don't compile built-in objects.
315# When we're building modules with modversions, we need to consider
316# the built-in objects during the descend as well, in order to
317# make sure the checksums are up to date before we record them.
318
319ifeq ($(MAKECMDGOALS),modules)
320 KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
321endif
322
323# If we have "make <whatever> modules", compile modules
324# in addition to whatever we do anyway.
325# Just "make" or "make all" shall build modules as well
326
327ifneq ($(filter all _all modules,$(MAKECMDGOALS)),)
328 KBUILD_MODULES := 1
329endif
330
331ifeq ($(MAKECMDGOALS),)
332 KBUILD_MODULES := 1
333endif
334
335export KBUILD_MODULES KBUILD_BUILTIN
336export KBUILD_CHECKSRC KBUILD_SRC KBUILD_EXTMOD
337
338# We need some generic definitions (do not try to remake the file).
339scripts/Kbuild.include: ;
340include scripts/Kbuild.include
341
342# Make variables (CC, etc...)
343AS = $(CROSS_COMPILE)as
344LD = $(CROSS_COMPILE)ld
345CC = $(CROSS_COMPILE)gcc
346CPP = $(CC) -E
347AR = $(CROSS_COMPILE)ar
348NM = $(CROSS_COMPILE)nm
349STRIP = $(CROSS_COMPILE)strip
350OBJCOPY = $(CROSS_COMPILE)objcopy
351OBJDUMP = $(CROSS_COMPILE)objdump
352AWK = awk
353GENKSYMS = scripts/genksyms/genksyms
354INSTALLKERNEL := installkernel
355DEPMOD = /sbin/depmod
356PERL = perl
357PYTHON = python
358CHECK = sparse
359
360CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
361 -Wbitwise -Wno-return-void $(CF)
362CFLAGS_MODULE =
363AFLAGS_MODULE =
364LDFLAGS_MODULE =
365CFLAGS_KERNEL =
366AFLAGS_KERNEL =
367CFLAGS_GCOV = -fprofile-arcs -ftest-coverage
368CFLAGS_KCOV = -fsanitize-coverage=trace-pc
369
370
371# Use USERINCLUDE when you must reference the UAPI directories only.
372USERINCLUDE := \
373 -I$(srctree)/arch/$(hdr-arch)/include/uapi \
374 -Iarch/$(hdr-arch)/include/generated/uapi \
375 -I$(srctree)/include/uapi \
376 -Iinclude/generated/uapi \
377 -include $(srctree)/include/linux/kconfig.h
378
379# Use LINUXINCLUDE when you must reference the include/ directory.
380# Needed to be compatible with the O= option
381LINUXINCLUDE := \
382 -I$(srctree)/arch/$(hdr-arch)/include \
383 -Iarch/$(hdr-arch)/include/generated/uapi \
384 -Iarch/$(hdr-arch)/include/generated \
385 $(if $(KBUILD_SRC), -I$(srctree)/include) \
386 -Iinclude \
387 $(USERINCLUDE)
388
389KBUILD_CPPFLAGS := -D__KERNEL__
390
391KBUILD_CFLAGS := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
392 -fno-strict-aliasing -fno-common \
393 -Werror-implicit-function-declaration \
394 -Wno-format-security \
395 -std=gnu89
396
397KBUILD_AFLAGS_KERNEL :=
398KBUILD_CFLAGS_KERNEL :=
399KBUILD_AFLAGS := -D__ASSEMBLY__
400KBUILD_AFLAGS_MODULE := -DMODULE
401KBUILD_CFLAGS_MODULE := -DMODULE
402KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
403
404# Read KERNELRELEASE from include/config/kernel.release (if it exists)
405KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
406KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
407
408export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
409export ARCH SRCARCH CONFIG_SHELL HOSTCC HOSTCFLAGS CROSS_COMPILE AS LD CC
410export CPP AR NM STRIP OBJCOPY OBJDUMP
411export MAKE AWK GENKSYMS INSTALLKERNEL PERL PYTHON UTS_MACHINE
412export HOSTCXX HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
413
414export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS LDFLAGS
415export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE CFLAGS_GCOV CFLAGS_KCOV CFLAGS_KASAN CFLAGS_UBSAN
416export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
417export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
418export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
419export KBUILD_ARFLAGS
420
421# When compiling out-of-tree modules, put MODVERDIR in the module
422# tree rather than in the kernel tree. The kernel tree might
423# even be read-only.
424export MODVERDIR := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_versions
425
426# Files to ignore in find ... statements
427
428export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o \
429 -name CVS -o -name .pc -o -name .hg -o -name .git \) \
430 -prune -o
431export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
432 --exclude CVS --exclude .pc --exclude .hg --exclude .git
433
434# ===========================================================================
435# Rules shared between *config targets and build targets
436
437# Basic helpers built in scripts
438PHONY += scripts_basic
439scripts_basic:
440 $(Q)$(MAKE) $(build)=scripts/basic
441 $(Q)rm -f .tmp_quiet_recordmcount
442
443# To avoid any implicit rule to kick in, define an empty command.
444scripts/basic/%: scripts_basic ;
445
446PHONY += outputmakefile
447# outputmakefile generates a Makefile in the output directory, if using a
448# separate output directory. This allows convenient use of make in the
449# output directory.
450outputmakefile:
451ifneq ($(KBUILD_SRC),)
452 $(Q)ln -fsn $(srctree) source
453 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile \
454 $(srctree) $(objtree) $(VERSION) $(PATCHLEVEL)
455endif
456
457# Support for using generic headers in asm-generic
458PHONY += asm-generic
459asm-generic:
460 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
461 src=asm obj=arch/$(SRCARCH)/include/generated/asm
462 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
463 src=uapi/asm obj=arch/$(SRCARCH)/include/generated/uapi/asm
464
465# To make sure we do not include .config for any of the *config targets
466# catch them early, and hand them over to scripts/kconfig/Makefile
467# It is allowed to specify more targets when calling make, including
468# mixing *config targets and build targets.
469# For example 'make oldconfig all'.
470# Detect when mixed targets is specified, and make a second invocation
471# of make so .config is not included in this case either (for *config).
472
473version_h := include/generated/uapi/linux/version.h
474old_version_h := include/linux/version.h
475
476no-dot-config-targets := clean mrproper distclean \
477 cscope gtags TAGS tags help% %docs check% coccicheck \
478 $(version_h) headers_% archheaders archscripts \
479 kernelversion %src-pkg
480
481config-targets := 0
482mixed-targets := 0
483dot-config := 1
484
485ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
486 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
487 dot-config := 0
488 endif
489endif
490
491ifeq ($(KBUILD_EXTMOD),)
492 ifneq ($(filter config %config,$(MAKECMDGOALS)),)
493 config-targets := 1
494 ifneq ($(words $(MAKECMDGOALS)),1)
495 mixed-targets := 1
496 endif
497 endif
498endif
499# install and module_install need also be processed one by one
500ifneq ($(filter install,$(MAKECMDGOALS)),)
501 ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
502 mixed-targets := 1
503 endif
504endif
505
506ifeq ($(mixed-targets),1)
507# ===========================================================================
508# We're called with mixed targets (*config and build targets).
509# Handle them one by one.
510
511PHONY += $(MAKECMDGOALS) __build_one_by_one
512
513$(filter-out __build_one_by_one, $(MAKECMDGOALS)): __build_one_by_one
514 @:
515
516__build_one_by_one:
517 $(Q)set -e; \
518 for i in $(MAKECMDGOALS); do \
519 $(MAKE) -f $(srctree)/Makefile $$i; \
520 done
521
522else
523ifeq ($(config-targets),1)
524# ===========================================================================
525# *config targets only - make sure prerequisites are updated, and descend
526# in scripts/kconfig to make the *config target
527
528# Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
529# KBUILD_DEFCONFIG may point out an alternative default configuration
530# used for 'make defconfig'
531include arch/$(SRCARCH)/Makefile
532export KBUILD_DEFCONFIG KBUILD_KCONFIG
533
534config: scripts_basic outputmakefile FORCE
535 $(Q)$(MAKE) $(build)=scripts/kconfig $@
536
537%config: scripts_basic outputmakefile FORCE
538 $(Q)$(MAKE) $(build)=scripts/kconfig $@
539
540else
541# ===========================================================================
542# Build targets only - this includes vmlinux, arch specific targets, clean
543# targets and others. In general all targets except *config targets.
544
545ifeq ($(KBUILD_EXTMOD),)
546# Additional helpers built in scripts
547# Carefully list dependencies so we do not try to build scripts twice
548# in parallel
549PHONY += scripts
550scripts: scripts_basic include/config/auto.conf include/config/tristate.conf \
551 asm-generic
552 $(Q)$(MAKE) $(build)=$(@)
553
554# Objects we will link into vmlinux / subdirs we need to visit
555init-y := init
556drivers-y := drivers sound firmware
557net-y := net
558libs-y := lib
559core-y := usr
560virt-y := virt
561endif # KBUILD_EXTMOD
562
563ifeq ($(dot-config),1)
564# Read in config
565-include include/config/auto.conf
566
567ifeq ($(KBUILD_EXTMOD),)
568# Read in dependencies to all Kconfig* files, make sure to run
569# oldconfig if changes are detected.
570-include include/config/auto.conf.cmd
571
572# To avoid any implicit rule to kick in, define an empty command
573$(KCONFIG_CONFIG) include/config/auto.conf.cmd: ;
574
575# If .config is newer than include/config/auto.conf, someone tinkered
576# with it and forgot to run make oldconfig.
577# if auto.conf.cmd is missing then we are probably in a cleaned tree so
578# we execute the config step to be sure to catch updated Kconfig files
579include/config/%.conf: $(KCONFIG_CONFIG) include/config/auto.conf.cmd
580 $(Q)$(MAKE) -f $(srctree)/Makefile silentoldconfig
581else
582# external modules needs include/generated/autoconf.h and include/config/auto.conf
583# but do not care if they are up-to-date. Use auto.conf to trigger the test
584PHONY += include/config/auto.conf
585
586include/config/auto.conf:
587 $(Q)test -e include/generated/autoconf.h -a -e $@ || ( \
588 echo >&2; \
589 echo >&2 " ERROR: Kernel configuration is invalid."; \
590 echo >&2 " include/generated/autoconf.h or $@ are missing.";\
591 echo >&2 " Run 'make oldconfig && make prepare' on kernel src to fix it."; \
592 echo >&2 ; \
593 /bin/false)
594
595endif # KBUILD_EXTMOD
596
597else
598# Dummy target needed, because used as prerequisite
599include/config/auto.conf: ;
600endif # $(dot-config)
601
602# The all: target is the default when no target is given on the
603# command line.
604# This allow a user to issue only 'make' to build a kernel including modules
605# Defaults to vmlinux, but the arch makefile usually adds further targets
606all: vmlinux
607
608# The arch Makefile can set ARCH_{CPP,A,C}FLAGS to override the default
609# values of the respective KBUILD_* variables
610ARCH_CPPFLAGS :=
611ARCH_AFLAGS :=
612ARCH_CFLAGS :=
613include arch/$(SRCARCH)/Makefile
614
615KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,)
616
617ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
618KBUILD_CFLAGS += -Os $(call cc-disable-warning,maybe-uninitialized,)
619else
620KBUILD_CFLAGS += -O2
621endif
622
623# Tell gcc to never replace conditional load with a non-conditional one
624KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
625
626ifdef CONFIG_READABLE_ASM
627# Disable optimizations that make assembler listings hard to read.
628# reorder blocks reorders the control in the function
629# ipa clone creates specialized cloned functions
630# partial inlining inlines only parts of functions
631KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
632 $(call cc-option,-fno-ipa-cp-clone,) \
633 $(call cc-option,-fno-partial-inlining)
634endif
635
636ifneq ($(CONFIG_FRAME_WARN),0)
637KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
638endif
639
640# Handle stack protector mode.
641#
642# Since kbuild can potentially perform two passes (first with the old
643# .config values and then with updated .config values), we cannot error out
644# if a desired compiler option is unsupported. If we were to error, kbuild
645# could never get to the second pass and actually notice that we changed
646# the option to something that was supported.
647#
648# Additionally, we don't want to fallback and/or silently change which compiler
649# flags will be used, since that leads to producing kernels with different
650# security feature characteristics depending on the compiler used. ("But I
651# selected CC_STACKPROTECTOR_STRONG! Why did it build with _REGULAR?!")
652#
653# The middle ground is to warn here so that the failed option is obvious, but
654# to let the build fail with bad compiler flags so that we can't produce a
655# kernel when there is a CONFIG and compiler mismatch.
656#
657ifdef CONFIG_CC_STACKPROTECTOR_REGULAR
658 stackp-flag := -fstack-protector
659 ifeq ($(call cc-option, $(stackp-flag)),)
660 $(warning Cannot use CONFIG_CC_STACKPROTECTOR_REGULAR: \
661 -fstack-protector not supported by compiler)
662 endif
663else
664ifdef CONFIG_CC_STACKPROTECTOR_STRONG
665 stackp-flag := -fstack-protector-strong
666 ifeq ($(call cc-option, $(stackp-flag)),)
667 $(warning Cannot use CONFIG_CC_STACKPROTECTOR_STRONG: \
668 -fstack-protector-strong not supported by compiler)
669 endif
670else
671 # Force off for distro compilers that enable stack protector by default.
672 stackp-flag := $(call cc-option, -fno-stack-protector)
673endif
674endif
675KBUILD_CFLAGS += $(stackp-flag)
676
677ifdef CONFIG_KCOV
678 ifeq ($(call cc-option, $(CFLAGS_KCOV)),)
679 $(warning Cannot use CONFIG_KCOV: \
680 -fsanitize-coverage=trace-pc is not supported by compiler)
681 CFLAGS_KCOV =
682 endif
683endif
684
685ifeq ($(cc-name),clang)
686KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
687KBUILD_CPPFLAGS += $(call cc-option,-Wno-unknown-warning-option,)
688KBUILD_CFLAGS += $(call cc-disable-warning, unused-variable)
689KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier)
690KBUILD_CFLAGS += $(call cc-disable-warning, gnu)
691# Quiet clang warning: comparison of unsigned expression < 0 is always false
692KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare)
693# CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
694# source of a reference will be _MergedGlobals and not on of the whitelisted names.
695# See modpost pattern 2
696KBUILD_CFLAGS += $(call cc-option, -mno-global-merge,)
697KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior)
698else
699
700# This warning generated too much noise in a regular build.
701# Use make W=1 to enable this warning (see scripts/Makefile.build)
702KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
703endif
704
705ifdef CONFIG_FRAME_POINTER
706KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
707else
708# Some targets (ARM with Thumb2, for example), can't be built with frame
709# pointers. For those, we don't have FUNCTION_TRACER automatically
710# select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
711# incompatible with -fomit-frame-pointer with current GCC, so we don't use
712# -fomit-frame-pointer with FUNCTION_TRACER.
713ifndef CONFIG_FUNCTION_TRACER
714KBUILD_CFLAGS += -fomit-frame-pointer
715endif
716endif
717
718KBUILD_CFLAGS += $(call cc-option, -fno-var-tracking-assignments)
719
720ifdef CONFIG_DEBUG_INFO
721ifdef CONFIG_DEBUG_INFO_SPLIT
722KBUILD_CFLAGS += $(call cc-option, -gsplit-dwarf, -g)
723else
724KBUILD_CFLAGS += -g
725endif
726KBUILD_AFLAGS += -Wa,-gdwarf-2
727endif
728ifdef CONFIG_DEBUG_INFO_DWARF4
729KBUILD_CFLAGS += $(call cc-option, -gdwarf-4,)
730endif
731
732ifdef CONFIG_DEBUG_INFO_REDUCED
733KBUILD_CFLAGS += $(call cc-option, -femit-struct-debug-baseonly) \
734 $(call cc-option,-fno-var-tracking)
735endif
736
737ifdef CONFIG_FUNCTION_TRACER
738ifndef CC_FLAGS_FTRACE
739CC_FLAGS_FTRACE := -pg
740endif
741export CC_FLAGS_FTRACE
742ifdef CONFIG_HAVE_FENTRY
743CC_USING_FENTRY := $(call cc-option, -mfentry -DCC_USING_FENTRY)
744endif
745KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_USING_FENTRY)
746KBUILD_AFLAGS += $(CC_USING_FENTRY)
747ifdef CONFIG_DYNAMIC_FTRACE
748 ifdef CONFIG_HAVE_C_RECORDMCOUNT
749 BUILD_C_RECORDMCOUNT := y
750 export BUILD_C_RECORDMCOUNT
751 endif
752endif
753endif
754
755# We trigger additional mismatches with less inlining
756ifdef CONFIG_DEBUG_SECTION_MISMATCH
757KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
758endif
759
760# arch Makefile may override CC so keep this after arch Makefile is included
761NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
762CHECKFLAGS += $(NOSTDINC_FLAGS)
763
764# warn about C99 declaration after statement
765KBUILD_CFLAGS += $(call cc-option,-Wdeclaration-after-statement,)
766
767# disable pointer signed / unsigned warnings in gcc 4.0
768KBUILD_CFLAGS += $(call cc-disable-warning, pointer-sign)
769
770# disable invalid "can't wrap" optimizations for signed / pointers
771KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow)
772
773# conserve stack if available
774KBUILD_CFLAGS += $(call cc-option,-fconserve-stack)
775
776# disallow errors like 'EXPORT_GPL(foo);' with missing header
777KBUILD_CFLAGS += $(call cc-option,-Werror=implicit-int)
778
779# require functions to have arguments in prototypes, not empty 'int foo()'
780KBUILD_CFLAGS += $(call cc-option,-Werror=strict-prototypes)
781
782# Prohibit date/time macros, which would make the build non-deterministic
783KBUILD_CFLAGS += $(call cc-option,-Werror=date-time)
784
785# enforce correct pointer usage
786KBUILD_CFLAGS += $(call cc-option,-Werror=incompatible-pointer-types)
787
788# use the deterministic mode of AR if available
789KBUILD_ARFLAGS := $(call ar-option,D)
790
791# check for 'asm goto'
792ifeq ($(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC)), y)
793 KBUILD_CFLAGS += -DCC_HAVE_ASM_GOTO
794 KBUILD_AFLAGS += -DCC_HAVE_ASM_GOTO
795endif
796
797include scripts/Makefile.kasan
798include scripts/Makefile.extrawarn
799include scripts/Makefile.ubsan
800
801# Add any arch overrides and user supplied CPPFLAGS, AFLAGS and CFLAGS as the
802# last assignments
803KBUILD_CPPFLAGS += $(ARCH_CPPFLAGS) $(KCPPFLAGS)
804KBUILD_AFLAGS += $(ARCH_AFLAGS) $(KAFLAGS)
805KBUILD_CFLAGS += $(ARCH_CFLAGS) $(KCFLAGS)
806
807# Use --build-id when available.
808LDFLAGS_BUILD_ID = $(patsubst -Wl$(comma)%,%,\
809 $(call cc-ldoption, -Wl$(comma)--build-id,))
810KBUILD_LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID)
811LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)
812
813ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
814LDFLAGS_vmlinux += $(call ld-option, -X,)
815endif
816
817# Default kernel image to build when no specific target is given.
818# KBUILD_IMAGE may be overruled on the command line or
819# set in the environment
820# Also any assignments in arch/$(ARCH)/Makefile take precedence over
821# this default value
822export KBUILD_IMAGE ?= vmlinux
823
824#
825# INSTALL_PATH specifies where to place the updated kernel and system map
826# images. Default is /boot, but you can set it to other values
827export INSTALL_PATH ?= /boot
828
829#
830# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
831# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
832# an argument if needed. Otherwise it defaults to the kernel install path
833#
834export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
835
836#
837# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
838# relocations required by build roots. This is not defined in the
839# makefile but the argument can be passed to make if needed.
840#
841
842MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
843export MODLIB
844
845#
846# INSTALL_MOD_STRIP, if defined, will cause modules to be
847# stripped after they are installed. If INSTALL_MOD_STRIP is '1', then
848# the default option --strip-debug will be used. Otherwise,
849# INSTALL_MOD_STRIP value will be used as the options to the strip command.
850
851ifdef INSTALL_MOD_STRIP
852ifeq ($(INSTALL_MOD_STRIP),1)
853mod_strip_cmd = $(STRIP) --strip-debug
854else
855mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
856endif # INSTALL_MOD_STRIP=1
857else
858mod_strip_cmd = true
859endif # INSTALL_MOD_STRIP
860export mod_strip_cmd
861
862# CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
863# after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
864# or CONFIG_MODULE_COMPRESS_XZ.
865
866mod_compress_cmd = true
867ifdef CONFIG_MODULE_COMPRESS
868 ifdef CONFIG_MODULE_COMPRESS_GZIP
869 mod_compress_cmd = gzip -n -f
870 endif # CONFIG_MODULE_COMPRESS_GZIP
871 ifdef CONFIG_MODULE_COMPRESS_XZ
872 mod_compress_cmd = xz -f
873 endif # CONFIG_MODULE_COMPRESS_XZ
874endif # CONFIG_MODULE_COMPRESS
875export mod_compress_cmd
876
877# Select initial ramdisk compression format, default is gzip(1).
878# This shall be used by the dracut(8) tool while creating an initramfs image.
879#
880INITRD_COMPRESS-y := gzip
881INITRD_COMPRESS-$(CONFIG_RD_BZIP2) := bzip2
882INITRD_COMPRESS-$(CONFIG_RD_LZMA) := lzma
883INITRD_COMPRESS-$(CONFIG_RD_XZ) := xz
884INITRD_COMPRESS-$(CONFIG_RD_LZO) := lzo
885INITRD_COMPRESS-$(CONFIG_RD_LZ4) := lz4
886# do not export INITRD_COMPRESS, since we didn't actually
887# choose a sane default compression above.
888# export INITRD_COMPRESS := $(INITRD_COMPRESS-y)
889
890ifdef CONFIG_MODULE_SIG_ALL
891$(eval $(call config_filename,MODULE_SIG_KEY))
892
893mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
894else
895mod_sign_cmd = true
896endif
897export mod_sign_cmd
898
899
900ifeq ($(KBUILD_EXTMOD),)
901core-y += kernel certs mm fs ipc security crypto block
902
903vmlinux-dirs := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
904 $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
905 $(net-y) $(net-m) $(libs-y) $(libs-m) $(virt-y)))
906
907vmlinux-alldirs := $(sort $(vmlinux-dirs) $(patsubst %/,%,$(filter %/, \
908 $(init-) $(core-) $(drivers-) $(net-) $(libs-) $(virt-))))
909
910init-y := $(patsubst %/, %/built-in.o, $(init-y))
911core-y := $(patsubst %/, %/built-in.o, $(core-y))
912drivers-y := $(patsubst %/, %/built-in.o, $(drivers-y))
913net-y := $(patsubst %/, %/built-in.o, $(net-y))
914libs-y1 := $(patsubst %/, %/lib.a, $(libs-y))
915libs-y2 := $(patsubst %/, %/built-in.o, $(libs-y))
916libs-y := $(libs-y1) $(libs-y2)
917virt-y := $(patsubst %/, %/built-in.o, $(virt-y))
918
919# Externally visible symbols (used by link-vmlinux.sh)
920export KBUILD_VMLINUX_INIT := $(head-y) $(init-y)
921export KBUILD_VMLINUX_MAIN := $(core-y) $(libs-y) $(drivers-y) $(net-y) $(virt-y)
922export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
923export LDFLAGS_vmlinux
924# used by scripts/pacmage/Makefile
925export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) arch Documentation include samples scripts tools)
926
927vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_INIT) $(KBUILD_VMLINUX_MAIN)
928
929# Final link of vmlinux
930 cmd_link-vmlinux = $(CONFIG_SHELL) $< $(LD) $(LDFLAGS) $(LDFLAGS_vmlinux)
931quiet_cmd_link-vmlinux = LINK $@
932
933# Include targets which we want to
934# execute if the rest of the kernel build went well.
935vmlinux: scripts/link-vmlinux.sh $(vmlinux-deps) FORCE
936ifdef CONFIG_HEADERS_CHECK
937 $(Q)$(MAKE) -f $(srctree)/Makefile headers_check
938endif
939ifdef CONFIG_SAMPLES
940 $(Q)$(MAKE) $(build)=samples
941endif
942ifdef CONFIG_BUILD_DOCSRC
943 $(Q)$(MAKE) $(build)=Documentation
944endif
945ifdef CONFIG_GDB_SCRIPTS
946 $(Q)ln -fsn `cd $(srctree) && /bin/pwd`/scripts/gdb/vmlinux-gdb.py
947endif
948 +$(call if_changed,link-vmlinux)
949
950# The actual objects are generated when descending,
951# make sure no implicit rule kicks in
952$(sort $(vmlinux-deps)): $(vmlinux-dirs) ;
953
954# Handle descending into subdirectories listed in $(vmlinux-dirs)
955# Preset locale variables to speed up the build process. Limit locale
956# tweaks to this spot to avoid wrong language settings when running
957# make menuconfig etc.
958# Error messages still appears in the original language
959
960PHONY += $(vmlinux-dirs)
961$(vmlinux-dirs): prepare scripts
962 $(Q)$(MAKE) $(build)=$@
963
964define filechk_kernel.release
965 echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
966endef
967
968# Store (new) KERNELRELEASE string in include/config/kernel.release
969include/config/kernel.release: include/config/auto.conf FORCE
970 $(call filechk,kernel.release)
971
972
973# Things we need to do before we recursively start building the kernel
974# or the modules are listed in "prepare".
975# A multi level approach is used. prepareN is processed before prepareN-1.
976# archprepare is used in arch Makefiles and when processed asm symlink,
977# version.h and scripts_basic is processed / created.
978
979# Listed in dependency order
980PHONY += prepare archprepare prepare0 prepare1 prepare2 prepare3
981
982# prepare3 is used to check if we are building in a separate output directory,
983# and if so do:
984# 1) Check that make has not been executed in the kernel src $(srctree)
985prepare3: include/config/kernel.release
986ifneq ($(KBUILD_SRC),)
987 @$(kecho) ' Using $(srctree) as source for kernel'
988 $(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \
989 echo >&2 " $(srctree) is not clean, please run 'make mrproper'"; \
990 echo >&2 " in the '$(srctree)' directory.";\
991 /bin/false; \
992 fi;
993endif
994
995# prepare2 creates a makefile if using a separate output directory
996prepare2: prepare3 outputmakefile asm-generic
997
998prepare1: prepare2 $(version_h) include/generated/utsrelease.h \
999 include/config/auto.conf
1000 $(cmd_crmodverdir)
1001
1002archprepare: archheaders archscripts prepare1 scripts_basic
1003
1004prepare0: archprepare FORCE
1005 $(Q)$(MAKE) $(build)=.
1006
1007# All the preparing..
1008prepare: prepare0 prepare-objtool
1009
1010ifdef CONFIG_STACK_VALIDATION
1011 has_libelf := $(call try-run,\
1012 echo "int main() {}" | $(HOSTCC) -xc -o /dev/null -lelf -,1,0)
1013 ifeq ($(has_libelf),1)
1014 objtool_target := tools/objtool FORCE
1015 else
1016 $(warning "Cannot use CONFIG_STACK_VALIDATION, please install libelf-dev or elfutils-libelf-devel")
1017 SKIP_STACK_VALIDATION := 1
1018 export SKIP_STACK_VALIDATION
1019 endif
1020endif
1021
1022PHONY += prepare-objtool
1023prepare-objtool: $(objtool_target)
1024
1025# Generate some files
1026# ---------------------------------------------------------------------------
1027
1028# KERNELRELEASE can change from a few different places, meaning version.h
1029# needs to be updated, so this check is forced on all builds
1030
1031uts_len := 64
1032define filechk_utsrelease.h
1033 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1034 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
1035 exit 1; \
1036 fi; \
1037 (echo \#define UTS_RELEASE \"$(KERNELRELEASE)\";)
1038endef
1039
1040define filechk_version.h
1041 (echo \#define LINUX_VERSION_CODE $(shell \
1042 expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1043 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))';)
1044endef
1045
1046$(version_h): $(srctree)/Makefile FORCE
1047 $(call filechk,version.h)
1048 $(Q)rm -f $(old_version_h)
1049
1050include/generated/utsrelease.h: include/config/kernel.release FORCE
1051 $(call filechk,utsrelease.h)
1052
1053PHONY += headerdep
1054headerdep:
1055 $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1056 $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1057
1058# ---------------------------------------------------------------------------
1059# Firmware install
1060INSTALL_FW_PATH=$(INSTALL_MOD_PATH)/lib/firmware
1061export INSTALL_FW_PATH
1062
1063PHONY += firmware_install
1064firmware_install: FORCE
1065 @mkdir -p $(objtree)/firmware
1066 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_install
1067
1068# ---------------------------------------------------------------------------
1069# Kernel headers
1070
1071#Default location for installed headers
1072export INSTALL_HDR_PATH = $(objtree)/usr
1073
1074# If we do an all arch process set dst to asm-$(hdr-arch)
1075hdr-dst = $(if $(KBUILD_HEADERS), dst=include/asm-$(hdr-arch), dst=include/asm)
1076
1077PHONY += archheaders
1078archheaders:
1079
1080PHONY += archscripts
1081archscripts:
1082
1083PHONY += __headers
1084__headers: $(version_h) scripts_basic asm-generic archheaders archscripts FORCE
1085 $(Q)$(MAKE) $(build)=scripts build_unifdef
1086
1087PHONY += headers_install_all
1088headers_install_all:
1089 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh install
1090
1091PHONY += headers_install
1092headers_install: __headers
1093 $(if $(wildcard $(srctree)/arch/$(hdr-arch)/include/uapi/asm/Kbuild),, \
1094 $(error Headers not exportable for the $(SRCARCH) architecture))
1095 $(Q)$(MAKE) $(hdr-inst)=include/uapi
1096 $(Q)$(MAKE) $(hdr-inst)=arch/$(hdr-arch)/include/uapi/asm $(hdr-dst)
1097
1098PHONY += headers_check_all
1099headers_check_all: headers_install_all
1100 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh check
1101
1102PHONY += headers_check
1103headers_check: headers_install
1104 $(Q)$(MAKE) $(hdr-inst)=include/uapi HDRCHECK=1
1105 $(Q)$(MAKE) $(hdr-inst)=arch/$(hdr-arch)/include/uapi/asm $(hdr-dst) HDRCHECK=1
1106
1107# ---------------------------------------------------------------------------
1108# Kernel selftest
1109
1110PHONY += kselftest
1111kselftest:
1112 $(Q)$(MAKE) -C tools/testing/selftests run_tests
1113
1114kselftest-clean:
1115 $(Q)$(MAKE) -C tools/testing/selftests clean
1116
1117PHONY += kselftest-merge
1118kselftest-merge:
1119 $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1120 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/kconfig/merge_config.sh \
1121 -m $(objtree)/.config \
1122 $(srctree)/tools/testing/selftests/*/config
1123 +$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1124
1125# ---------------------------------------------------------------------------
1126# Modules
1127
1128ifdef CONFIG_MODULES
1129
1130# By default, build modules as well
1131
1132all: modules
1133
1134# Build modules
1135#
1136# A module can be listed more than once in obj-m resulting in
1137# duplicate lines in modules.order files. Those are removed
1138# using awk while concatenating to the final file.
1139
1140PHONY += modules
1141modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux) modules.builtin
1142 $(Q)$(AWK) '!x[$$0]++' $(vmlinux-dirs:%=$(objtree)/%/modules.order) > $(objtree)/modules.order
1143 @$(kecho) ' Building modules, stage 2.';
1144 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1145 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_modbuild
1146
1147modules.builtin: $(vmlinux-dirs:%=%/modules.builtin)
1148 $(Q)$(AWK) '!x[$$0]++' $^ > $(objtree)/modules.builtin
1149
1150%/modules.builtin: include/config/auto.conf
1151 $(Q)$(MAKE) $(modbuiltin)=$*
1152
1153
1154# Target to prepare building external modules
1155PHONY += modules_prepare
1156modules_prepare: prepare scripts
1157
1158# Target to install modules
1159PHONY += modules_install
1160modules_install: _modinst_ _modinst_post
1161
1162PHONY += _modinst_
1163_modinst_:
1164 @rm -rf $(MODLIB)/kernel
1165 @rm -f $(MODLIB)/source
1166 @mkdir -p $(MODLIB)/kernel
1167 @ln -s `cd $(srctree) && /bin/pwd` $(MODLIB)/source
1168 @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
1169 rm -f $(MODLIB)/build ; \
1170 ln -s $(CURDIR) $(MODLIB)/build ; \
1171 fi
1172 @cp -f $(objtree)/modules.order $(MODLIB)/
1173 @cp -f $(objtree)/modules.builtin $(MODLIB)/
1174 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1175
1176# This depmod is only for convenience to give the initial
1177# boot a modules.dep even before / is mounted read-write. However the
1178# boot script depmod is the master version.
1179PHONY += _modinst_post
1180_modinst_post: _modinst_
1181 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_modinst
1182 $(call cmd,depmod)
1183
1184ifeq ($(CONFIG_MODULE_SIG), y)
1185PHONY += modules_sign
1186modules_sign:
1187 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1188endif
1189
1190else # CONFIG_MODULES
1191
1192# Modules not configured
1193# ---------------------------------------------------------------------------
1194
1195modules modules_install: FORCE
1196 @echo >&2
1197 @echo >&2 "The present kernel configuration has modules disabled."
1198 @echo >&2 "Type 'make config' and enable loadable module support."
1199 @echo >&2 "Then build a kernel with module support enabled."
1200 @echo >&2
1201 @exit 1
1202
1203endif # CONFIG_MODULES
1204
1205###
1206# Cleaning is done on three levels.
1207# make clean Delete most generated files
1208# Leave enough to build external modules
1209# make mrproper Delete the current configuration, and all generated files
1210# make distclean Remove editor backup files, patch leftover files and the like
1211
1212# Directories & files removed with 'make clean'
1213CLEAN_DIRS += $(MODVERDIR)
1214
1215# Directories & files removed with 'make mrproper'
1216MRPROPER_DIRS += include/config usr/include include/generated \
1217 arch/*/include/generated .tmp_objdiff
1218MRPROPER_FILES += .config .config.old .version .old_version \
1219 Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS \
1220 signing_key.pem signing_key.priv signing_key.x509 \
1221 x509.genkey extra_certificates signing_key.x509.keyid \
1222 signing_key.x509.signer vmlinux-gdb.py
1223
1224# clean - Delete most, but leave enough to build external modules
1225#
1226clean: rm-dirs := $(CLEAN_DIRS)
1227clean: rm-files := $(CLEAN_FILES)
1228clean-dirs := $(addprefix _clean_, . $(vmlinux-alldirs) Documentation samples)
1229
1230PHONY += $(clean-dirs) clean archclean vmlinuxclean
1231$(clean-dirs):
1232 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1233
1234vmlinuxclean:
1235 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1236
1237clean: archclean vmlinuxclean
1238
1239# mrproper - Delete all generated files, including .config
1240#
1241mrproper: rm-dirs := $(wildcard $(MRPROPER_DIRS))
1242mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1243mrproper-dirs := $(addprefix _mrproper_,Documentation/DocBook scripts)
1244
1245PHONY += $(mrproper-dirs) mrproper archmrproper
1246$(mrproper-dirs):
1247 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1248
1249mrproper: clean archmrproper $(mrproper-dirs)
1250 $(call cmd,rmdirs)
1251 $(call cmd,rmfiles)
1252
1253# distclean
1254#
1255PHONY += distclean
1256
1257distclean: mrproper
1258 @find $(srctree) $(RCS_FIND_IGNORE) \
1259 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1260 -o -name '*.bak' -o -name '#*#' -o -name '.*.orig' \
1261 -o -name '.*.rej' -o -name '*%' -o -name 'core' \) \
1262 -type f -print | xargs rm -f
1263
1264
1265# Packaging of the kernel to various formats
1266# ---------------------------------------------------------------------------
1267# rpm target kept for backward compatibility
1268package-dir := scripts/package
1269
1270%src-pkg: FORCE
1271 $(Q)$(MAKE) $(build)=$(package-dir) $@
1272%pkg: include/config/kernel.release FORCE
1273 $(Q)$(MAKE) $(build)=$(package-dir) $@
1274rpm: include/config/kernel.release FORCE
1275 $(Q)$(MAKE) $(build)=$(package-dir) $@
1276
1277
1278# Brief documentation of the typical targets used
1279# ---------------------------------------------------------------------------
1280
1281boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1282boards := $(sort $(notdir $(boards)))
1283board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1284board-dirs := $(sort $(notdir $(board-dirs:/=)))
1285
1286help:
1287 @echo 'Cleaning targets:'
1288 @echo ' clean - Remove most generated files but keep the config and'
1289 @echo ' enough build support to build external modules'
1290 @echo ' mrproper - Remove all generated files + config + various backup files'
1291 @echo ' distclean - mrproper + remove editor backup and patch files'
1292 @echo ''
1293 @echo 'Configuration targets:'
1294 @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1295 @echo ''
1296 @echo 'Other generic targets:'
1297 @echo ' all - Build all targets marked with [*]'
1298 @echo '* vmlinux - Build the bare kernel'
1299 @echo '* modules - Build all modules'
1300 @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1301 @echo ' firmware_install- Install all firmware to INSTALL_FW_PATH'
1302 @echo ' (default: $$(INSTALL_MOD_PATH)/lib/firmware)'
1303 @echo ' dir/ - Build all files in dir and below'
1304 @echo ' dir/file.[ois] - Build specified target only'
1305 @echo ' dir/file.lst - Build specified mixed source/assembly target only'
1306 @echo ' (requires a recent binutils and recent build (System.map))'
1307 @echo ' dir/file.ko - Build module including final link'
1308 @echo ' modules_prepare - Set up for building external modules'
1309 @echo ' tags/TAGS - Generate tags file for editors'
1310 @echo ' cscope - Generate cscope index'
1311 @echo ' gtags - Generate GNU GLOBAL index'
1312 @echo ' kernelrelease - Output the release version string (use with make -s)'
1313 @echo ' kernelversion - Output the version stored in Makefile (use with make -s)'
1314 @echo ' image_name - Output the image name (use with make -s)'
1315 @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1316 echo ' (default: $(INSTALL_HDR_PATH))'; \
1317 echo ''
1318 @echo 'Static analysers'
1319 @echo ' checkstack - Generate a list of stack hogs'
1320 @echo ' namespacecheck - Name space analysis on compiled kernel'
1321 @echo ' versioncheck - Sanity check on version.h usage'
1322 @echo ' includecheck - Check for duplicate included header files'
1323 @echo ' export_report - List the usages of all exported symbols'
1324 @echo ' headers_check - Sanity check on exported headers'
1325 @echo ' headerdep - Detect inclusion cycles in headers'
1326 @$(MAKE) -f $(srctree)/scripts/Makefile.help checker-help
1327 @echo ''
1328 @echo 'Kernel selftest'
1329 @echo ' kselftest - Build and run kernel selftest (run as root)'
1330 @echo ' Build, install, and boot kernel before'
1331 @echo ' running kselftest on it'
1332 @echo ' kselftest-clean - Remove all generated kselftest files'
1333 @echo ' kselftest-merge - Merge all the config dependencies of kselftest to existed'
1334 @echo ' .config.'
1335 @echo ''
1336 @echo 'Kernel packaging:'
1337 @$(MAKE) $(build)=$(package-dir) help
1338 @echo ''
1339 @echo 'Documentation targets:'
1340 @$(MAKE) -f $(srctree)/Documentation/DocBook/Makefile dochelp
1341 @echo ''
1342 @echo 'Architecture specific targets ($(SRCARCH)):'
1343 @$(if $(archhelp),$(archhelp),\
1344 echo ' No architecture specific help defined for $(SRCARCH)')
1345 @echo ''
1346 @$(if $(boards), \
1347 $(foreach b, $(boards), \
1348 printf " %-24s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1349 echo '')
1350 @$(if $(board-dirs), \
1351 $(foreach b, $(board-dirs), \
1352 printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1353 printf " %-16s - Show all of the above\\n" help-boards; \
1354 echo '')
1355
1356 @echo ' make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1357 @echo ' make V=2 [targets] 2 => give reason for rebuild of target'
1358 @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
1359 @echo ' make C=1 [targets] Check all c source with $$CHECK (sparse by default)'
1360 @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
1361 @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1362 @echo ' make W=n [targets] Enable extra gcc checks, n=1,2,3 where'
1363 @echo ' 1: warnings which may be relevant and do not occur too often'
1364 @echo ' 2: warnings which occur quite often but may still be relevant'
1365 @echo ' 3: more obscure warnings, can most likely be ignored'
1366 @echo ' Multiple levels can be combined with W=12 or W=123'
1367 @echo ''
1368 @echo 'Execute "make" or "make all" to build all targets marked with [*] '
1369 @echo 'For further info see the ./README file'
1370
1371
1372help-board-dirs := $(addprefix help-,$(board-dirs))
1373
1374help-boards: $(help-board-dirs)
1375
1376boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1377
1378$(help-board-dirs): help-%:
1379 @echo 'Architecture specific targets ($(SRCARCH) $*):'
1380 @$(if $(boards-per-dir), \
1381 $(foreach b, $(boards-per-dir), \
1382 printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1383 echo '')
1384
1385
1386# Documentation targets
1387# ---------------------------------------------------------------------------
1388%docs: scripts_basic FORCE
1389 $(Q)$(MAKE) $(build)=scripts build_docproc build_check-lc_ctype
1390 $(Q)$(MAKE) $(build)=Documentation/DocBook $@
1391
1392else # KBUILD_EXTMOD
1393
1394###
1395# External module support.
1396# When building external modules the kernel used as basis is considered
1397# read-only, and no consistency checks are made and the make
1398# system is not used on the basis kernel. If updates are required
1399# in the basis kernel ordinary make commands (without M=...) must
1400# be used.
1401#
1402# The following are the only valid targets when building external
1403# modules.
1404# make M=dir clean Delete all automatically generated files
1405# make M=dir modules Make all modules in specified dir
1406# make M=dir Same as 'make M=dir modules'
1407# make M=dir modules_install
1408# Install the modules built in the module directory
1409# Assumes install directory is already created
1410
1411# We are always building modules
1412KBUILD_MODULES := 1
1413PHONY += crmodverdir
1414crmodverdir:
1415 $(cmd_crmodverdir)
1416
1417PHONY += $(objtree)/Module.symvers
1418$(objtree)/Module.symvers:
1419 @test -e $(objtree)/Module.symvers || ( \
1420 echo; \
1421 echo " WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1422 echo " is missing; modules will have no dependencies and modversions."; \
1423 echo )
1424
1425module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
1426PHONY += $(module-dirs) modules
1427$(module-dirs): crmodverdir $(objtree)/Module.symvers
1428 $(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@)
1429
1430modules: $(module-dirs)
1431 @$(kecho) ' Building modules, stage 2.';
1432 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1433
1434PHONY += modules_install
1435modules_install: _emodinst_ _emodinst_post
1436
1437install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1438PHONY += _emodinst_
1439_emodinst_:
1440 $(Q)mkdir -p $(MODLIB)/$(install-dir)
1441 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1442
1443PHONY += _emodinst_post
1444_emodinst_post: _emodinst_
1445 $(call cmd,depmod)
1446
1447clean-dirs := $(addprefix _clean_,$(KBUILD_EXTMOD))
1448
1449PHONY += $(clean-dirs) clean
1450$(clean-dirs):
1451 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1452
1453clean: rm-dirs := $(MODVERDIR)
1454clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers
1455
1456help:
1457 @echo ' Building external modules.'
1458 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1459 @echo ''
1460 @echo ' modules - default target, build the module(s)'
1461 @echo ' modules_install - install the module'
1462 @echo ' clean - remove generated files in module directory only'
1463 @echo ''
1464
1465# Dummies...
1466PHONY += prepare scripts
1467prepare: ;
1468scripts: ;
1469endif # KBUILD_EXTMOD
1470
1471clean: $(clean-dirs)
1472 $(call cmd,rmdirs)
1473 $(call cmd,rmfiles)
1474 @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1475 \( -name '*.[oas]' -o -name '*.ko' -o -name '.*.cmd' \
1476 -o -name '*.ko.*' \
1477 -o -name '*.dwo' \
1478 -o -name '*.su' \
1479 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1480 -o -name '*.symtypes' -o -name 'modules.order' \
1481 -o -name modules.builtin -o -name '.tmp_*.o.*' \
1482 -o -name '*.gcno' \) -type f -print | xargs rm -f
1483
1484# Generate tags for editors
1485# ---------------------------------------------------------------------------
1486quiet_cmd_tags = GEN $@
1487 cmd_tags = $(CONFIG_SHELL) $(srctree)/scripts/tags.sh $@
1488
1489tags TAGS cscope gtags: FORCE
1490 $(call cmd,tags)
1491
1492# Scripts to check various things for consistency
1493# ---------------------------------------------------------------------------
1494
1495PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1496
1497includecheck:
1498 find $(srctree)/* $(RCS_FIND_IGNORE) \
1499 -name '*.[hcS]' -type f -print | sort \
1500 | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1501
1502versioncheck:
1503 find $(srctree)/* $(RCS_FIND_IGNORE) \
1504 -name '*.[hcS]' -type f -print | sort \
1505 | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1506
1507coccicheck:
1508 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/$@
1509
1510namespacecheck:
1511 $(PERL) $(srctree)/scripts/namespace.pl
1512
1513export_report:
1514 $(PERL) $(srctree)/scripts/export_report.pl
1515
1516endif #ifeq ($(config-targets),1)
1517endif #ifeq ($(mixed-targets),1)
1518
1519PHONY += checkstack kernelrelease kernelversion image_name
1520
1521# UML needs a little special treatment here. It wants to use the host
1522# toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
1523# else wants $(ARCH), including people doing cross-builds, which means
1524# that $(SUBARCH) doesn't work here.
1525ifeq ($(ARCH), um)
1526CHECKSTACK_ARCH := $(SUBARCH)
1527else
1528CHECKSTACK_ARCH := $(ARCH)
1529endif
1530checkstack:
1531 $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1532 $(PERL) $(src)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1533
1534kernelrelease:
1535 @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1536
1537kernelversion:
1538 @echo $(KERNELVERSION)
1539
1540image_name:
1541 @echo $(KBUILD_IMAGE)
1542
1543# Clear a bunch of variables before executing the submake
1544tools/: FORCE
1545 $(Q)mkdir -p $(objtree)/tools
1546 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(filter --j% -j,$(MAKEFLAGS))" O=$(shell cd $(objtree) && /bin/pwd) subdir=tools -C $(src)/tools/
1547
1548tools/%: FORCE
1549 $(Q)mkdir -p $(objtree)/tools
1550 $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(filter --j% -j,$(MAKEFLAGS))" O=$(shell cd $(objtree) && /bin/pwd) subdir=tools -C $(src)/tools/ $*
1551
1552# Single targets
1553# ---------------------------------------------------------------------------
1554# Single targets are compatible with:
1555# - build with mixed source and output
1556# - build with separate output dir 'make O=...'
1557# - external modules
1558#
1559# target-dir => where to store outputfile
1560# build-dir => directory in kernel source tree to use
1561
1562ifeq ($(KBUILD_EXTMOD),)
1563 build-dir = $(patsubst %/,%,$(dir $@))
1564 target-dir = $(dir $@)
1565else
1566 zap-slash=$(filter-out .,$(patsubst %/,%,$(dir $@)))
1567 build-dir = $(KBUILD_EXTMOD)$(if $(zap-slash),/$(zap-slash))
1568 target-dir = $(if $(KBUILD_EXTMOD),$(dir $<),$(dir $@))
1569endif
1570
1571%.s: %.c prepare scripts FORCE
1572 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1573%.i: %.c prepare scripts FORCE
1574 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1575%.o: %.c prepare scripts FORCE
1576 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1577%.lst: %.c prepare scripts FORCE
1578 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1579%.s: %.S prepare scripts FORCE
1580 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1581%.o: %.S prepare scripts FORCE
1582 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1583%.symtypes: %.c prepare scripts FORCE
1584 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1585
1586# Modules
1587/: prepare scripts FORCE
1588 $(cmd_crmodverdir)
1589 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1590 $(build)=$(build-dir)
1591# Make sure the latest headers are built for Documentation
1592Documentation/: headers_install
1593%/: prepare scripts FORCE
1594 $(cmd_crmodverdir)
1595 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1596 $(build)=$(build-dir)
1597%.ko: prepare scripts FORCE
1598 $(cmd_crmodverdir)
1599 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1600 $(build)=$(build-dir) $(@:.ko=.o)
1601 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1602
1603# FIXME Should go into a make.lib or something
1604# ===========================================================================
1605
1606quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN $(wildcard $(rm-dirs)))
1607 cmd_rmdirs = rm -rf $(rm-dirs)
1608
1609quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
1610 cmd_rmfiles = rm -f $(rm-files)
1611
1612# Run depmod only if we have System.map and depmod is executable
1613quiet_cmd_depmod = DEPMOD $(KERNELRELEASE)
1614 cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1615 $(KERNELRELEASE) "$(patsubst y,_,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX))"
1616
1617# Create temporary dir for module support files
1618# clean it up only when building all modules
1619cmd_crmodverdir = $(Q)mkdir -p $(MODVERDIR) \
1620 $(if $(KBUILD_MODULES),; rm -f $(MODVERDIR)/*)
1621
1622# read all saved command lines
1623
1624targets := $(wildcard $(sort $(targets)))
1625cmd_files := $(wildcard .*.cmd $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
1626
1627ifneq ($(cmd_files),)
1628 $(cmd_files): ; # Do not try to update included dependency files
1629 include $(cmd_files)
1630endif
1631
1632endif # skip-makefile
1633
1634PHONY += FORCE
1635FORCE:
1636
1637# Declare the contents of the .PHONY variable as phony. We keep that
1638# information in a variable so we can use it in if_changed and friends.
1639.PHONY: $(PHONY)