xref: /openbmc/linux/Makefile (revision 165f2d28)
1# SPDX-License-Identifier: GPL-2.0
2VERSION = 5
3PATCHLEVEL = 7
4SUBLEVEL = 0
5EXTRAVERSION = -rc5
6NAME = Kleptomaniac Octopus
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
14# That's our default target when none is given on the command line
15PHONY := _all
16_all:
17
18# We are using a recursive build, so we need to do a little thinking
19# to get the ordering right.
20#
21# Most importantly: sub-Makefiles should only ever modify files in
22# their own directory. If in some directory we have a dependency on
23# a file in another dir (which doesn't happen often, but it's often
24# unavoidable when linking the built-in.a targets which finally
25# turn into vmlinux), we will call a sub make in that other dir, and
26# after that we are sure that everything which is in that other dir
27# is now up to date.
28#
29# The only cases where we need to modify files which have global
30# effects are thus separated out and done before the recursive
31# descending is started. They are now explicitly listed as the
32# prepare rule.
33
34ifneq ($(sub_make_done),1)
35
36# Do not use make's built-in rules and variables
37# (this increases performance and avoids hard-to-debug behaviour)
38MAKEFLAGS += -rR
39
40# Avoid funny character set dependencies
41unexport LC_ALL
42LC_COLLATE=C
43LC_NUMERIC=C
44export LC_COLLATE LC_NUMERIC
45
46# Avoid interference with shell env settings
47unexport GREP_OPTIONS
48
49# Beautify output
50# ---------------------------------------------------------------------------
51#
52# Normally, we echo the whole command before executing it. By making
53# that echo $($(quiet)$(cmd)), we now have the possibility to set
54# $(quiet) to choose other forms of output instead, e.g.
55#
56#         quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
57#         cmd_cc_o_c       = $(CC) $(c_flags) -c -o $@ $<
58#
59# If $(quiet) is empty, the whole command will be printed.
60# If it is set to "quiet_", only the short version will be printed.
61# If it is set to "silent_", nothing will be printed at all, since
62# the variable $(silent_cmd_cc_o_c) doesn't exist.
63#
64# A simple variant is to prefix commands with $(Q) - that's useful
65# for commands that shall be hidden in non-verbose mode.
66#
67#	$(Q)ln $@ :<
68#
69# If KBUILD_VERBOSE equals 0 then the above command will be hidden.
70# If KBUILD_VERBOSE equals 1 then the above command is displayed.
71# If KBUILD_VERBOSE equals 2 then give the reason why each target is rebuilt.
72#
73# To put more focus on warnings, be less verbose as default
74# Use 'make V=1' to see the full commands
75
76ifeq ("$(origin V)", "command line")
77  KBUILD_VERBOSE = $(V)
78endif
79ifndef KBUILD_VERBOSE
80  KBUILD_VERBOSE = 0
81endif
82
83ifeq ($(KBUILD_VERBOSE),1)
84  quiet =
85  Q =
86else
87  quiet=quiet_
88  Q = @
89endif
90
91# If the user is running make -s (silent mode), suppress echoing of
92# commands
93
94ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
95  quiet=silent_
96endif
97
98export quiet Q KBUILD_VERBOSE
99
100# Kbuild will save output files in the current working directory.
101# This does not need to match to the root of the kernel source tree.
102#
103# For example, you can do this:
104#
105#  cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
106#
107# If you want to save output files in a different location, there are
108# two syntaxes to specify it.
109#
110# 1) O=
111# Use "make O=dir/to/store/output/files/"
112#
113# 2) Set KBUILD_OUTPUT
114# Set the environment variable KBUILD_OUTPUT to point to the output directory.
115# export KBUILD_OUTPUT=dir/to/store/output/files/; make
116#
117# The O= assignment takes precedence over the KBUILD_OUTPUT environment
118# variable.
119
120# Do we want to change the working directory?
121ifeq ("$(origin O)", "command line")
122  KBUILD_OUTPUT := $(O)
123endif
124
125ifneq ($(KBUILD_OUTPUT),)
126# Make's built-in functions such as $(abspath ...), $(realpath ...) cannot
127# expand a shell special character '~'. We use a somewhat tedious way here.
128abs_objtree := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) && pwd)
129$(if $(abs_objtree),, \
130     $(error failed to create output directory "$(KBUILD_OUTPUT)"))
131
132# $(realpath ...) resolves symlinks
133abs_objtree := $(realpath $(abs_objtree))
134else
135abs_objtree := $(CURDIR)
136endif # ifneq ($(KBUILD_OUTPUT),)
137
138ifeq ($(abs_objtree),$(CURDIR))
139# Suppress "Entering directory ..." unless we are changing the work directory.
140MAKEFLAGS += --no-print-directory
141else
142need-sub-make := 1
143endif
144
145abs_srctree := $(realpath $(dir $(lastword $(MAKEFILE_LIST))))
146
147ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
148$(error source directory cannot contain spaces or colons)
149endif
150
151ifneq ($(abs_srctree),$(abs_objtree))
152# Look for make include files relative to root of kernel src
153#
154# This does not become effective immediately because MAKEFLAGS is re-parsed
155# once after the Makefile is read. We need to invoke sub-make.
156MAKEFLAGS += --include-dir=$(abs_srctree)
157need-sub-make := 1
158endif
159
160ifneq ($(filter 3.%,$(MAKE_VERSION)),)
161# 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
162# We need to invoke sub-make to avoid implicit rules in the top Makefile.
163need-sub-make := 1
164# Cancel implicit rules for this Makefile.
165$(lastword $(MAKEFILE_LIST)): ;
166endif
167
168export abs_srctree abs_objtree
169export sub_make_done := 1
170
171ifeq ($(need-sub-make),1)
172
173PHONY += $(MAKECMDGOALS) sub-make
174
175$(filter-out _all sub-make $(lastword $(MAKEFILE_LIST)), $(MAKECMDGOALS)) _all: sub-make
176	@:
177
178# Invoke a second make in the output directory, passing relevant variables
179sub-make:
180	$(Q)$(MAKE) -C $(abs_objtree) -f $(abs_srctree)/Makefile $(MAKECMDGOALS)
181
182endif # need-sub-make
183endif # sub_make_done
184
185# We process the rest of the Makefile if this is the final invocation of make
186ifeq ($(need-sub-make),)
187
188# Do not print "Entering directory ...",
189# but we want to display it when entering to the output directory
190# so that IDEs/editors are able to understand relative filenames.
191MAKEFLAGS += --no-print-directory
192
193# Call a source code checker (by default, "sparse") as part of the
194# C compilation.
195#
196# Use 'make C=1' to enable checking of only re-compiled files.
197# Use 'make C=2' to enable checking of *all* source files, regardless
198# of whether they are re-compiled or not.
199#
200# See the file "Documentation/dev-tools/sparse.rst" for more details,
201# including where to get the "sparse" utility.
202
203ifeq ("$(origin C)", "command line")
204  KBUILD_CHECKSRC = $(C)
205endif
206ifndef KBUILD_CHECKSRC
207  KBUILD_CHECKSRC = 0
208endif
209
210# Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
211# directory of external module to build. Setting M= takes precedence.
212ifeq ("$(origin M)", "command line")
213  KBUILD_EXTMOD := $(M)
214endif
215
216export KBUILD_CHECKSRC KBUILD_EXTMOD
217
218extmod-prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
219
220ifeq ($(abs_srctree),$(abs_objtree))
221        # building in the source tree
222        srctree := .
223	building_out_of_srctree :=
224else
225        ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
226                # building in a subdirectory of the source tree
227                srctree := ..
228        else
229                srctree := $(abs_srctree)
230        endif
231	building_out_of_srctree := 1
232endif
233
234ifneq ($(KBUILD_ABS_SRCTREE),)
235srctree := $(abs_srctree)
236endif
237
238objtree		:= .
239VPATH		:= $(srctree)
240
241export building_out_of_srctree srctree objtree VPATH
242
243# To make sure we do not include .config for any of the *config targets
244# catch them early, and hand them over to scripts/kconfig/Makefile
245# It is allowed to specify more targets when calling make, including
246# mixing *config targets and build targets.
247# For example 'make oldconfig all'.
248# Detect when mixed targets is specified, and make a second invocation
249# of make so .config is not included in this case either (for *config).
250
251version_h := include/generated/uapi/linux/version.h
252old_version_h := include/linux/version.h
253
254clean-targets := %clean mrproper cleandocs
255no-dot-config-targets := $(clean-targets) \
256			 cscope gtags TAGS tags help% %docs check% coccicheck \
257			 $(version_h) headers headers_% archheaders archscripts \
258			 %asm-generic kernelversion %src-pkg dt_binding_check \
259			 outputmakefile
260no-sync-config-targets := $(no-dot-config-targets) install %install \
261			   kernelrelease
262single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
263
264config-build	:=
265mixed-build	:=
266need-config	:= 1
267may-sync-config	:= 1
268single-build	:=
269
270ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
271	ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
272		need-config :=
273	endif
274endif
275
276ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
277	ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
278		may-sync-config :=
279	endif
280endif
281
282ifneq ($(KBUILD_EXTMOD),)
283	may-sync-config :=
284endif
285
286ifeq ($(KBUILD_EXTMOD),)
287        ifneq ($(filter config %config,$(MAKECMDGOALS)),)
288		config-build := 1
289                ifneq ($(words $(MAKECMDGOALS)),1)
290			mixed-build := 1
291                endif
292        endif
293endif
294
295# We cannot build single targets and the others at the same time
296ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
297	single-build := 1
298	ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
299		mixed-build := 1
300	endif
301endif
302
303# For "make -j clean all", "make -j mrproper defconfig all", etc.
304ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
305        ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
306		mixed-build := 1
307        endif
308endif
309
310# install and modules_install need also be processed one by one
311ifneq ($(filter install,$(MAKECMDGOALS)),)
312        ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
313		mixed-build := 1
314        endif
315endif
316
317ifdef mixed-build
318# ===========================================================================
319# We're called with mixed targets (*config and build targets).
320# Handle them one by one.
321
322PHONY += $(MAKECMDGOALS) __build_one_by_one
323
324$(filter-out __build_one_by_one, $(MAKECMDGOALS)): __build_one_by_one
325	@:
326
327__build_one_by_one:
328	$(Q)set -e; \
329	for i in $(MAKECMDGOALS); do \
330		$(MAKE) -f $(srctree)/Makefile $$i; \
331	done
332
333else # !mixed-build
334
335include scripts/Kbuild.include
336
337# Read KERNELRELEASE from include/config/kernel.release (if it exists)
338KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
339KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
340export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
341
342include scripts/subarch.include
343
344# Cross compiling and selecting different set of gcc/bin-utils
345# ---------------------------------------------------------------------------
346#
347# When performing cross compilation for other architectures ARCH shall be set
348# to the target architecture. (See arch/* for the possibilities).
349# ARCH can be set during invocation of make:
350# make ARCH=ia64
351# Another way is to have ARCH set in the environment.
352# The default ARCH is the host where make is executed.
353
354# CROSS_COMPILE specify the prefix used for all executables used
355# during compilation. Only gcc and related bin-utils executables
356# are prefixed with $(CROSS_COMPILE).
357# CROSS_COMPILE can be set on the command line
358# make CROSS_COMPILE=ia64-linux-
359# Alternatively CROSS_COMPILE can be set in the environment.
360# Default value for CROSS_COMPILE is not to prefix executables
361# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
362ARCH		?= $(SUBARCH)
363
364# Architecture as present in compile.h
365UTS_MACHINE 	:= $(ARCH)
366SRCARCH 	:= $(ARCH)
367
368# Additional ARCH settings for x86
369ifeq ($(ARCH),i386)
370        SRCARCH := x86
371endif
372ifeq ($(ARCH),x86_64)
373        SRCARCH := x86
374endif
375
376# Additional ARCH settings for sparc
377ifeq ($(ARCH),sparc32)
378       SRCARCH := sparc
379endif
380ifeq ($(ARCH),sparc64)
381       SRCARCH := sparc
382endif
383
384# Additional ARCH settings for sh
385ifeq ($(ARCH),sh64)
386       SRCARCH := sh
387endif
388
389KCONFIG_CONFIG	?= .config
390export KCONFIG_CONFIG
391
392# Default file for 'make defconfig'. This may be overridden by arch-Makefile.
393export KBUILD_DEFCONFIG := defconfig
394
395# SHELL used by kbuild
396CONFIG_SHELL := sh
397
398HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
399HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
400HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
401
402ifneq ($(LLVM),)
403HOSTCC	= clang
404HOSTCXX	= clang++
405else
406HOSTCC	= gcc
407HOSTCXX	= g++
408endif
409KBUILD_HOSTCFLAGS   := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 \
410		-fomit-frame-pointer -std=gnu89 $(HOST_LFS_CFLAGS) \
411		$(HOSTCFLAGS)
412KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
413KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
414KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
415
416# Make variables (CC, etc...)
417CPP		= $(CC) -E
418ifneq ($(LLVM),)
419CC		= clang
420LD		= ld.lld
421AR		= llvm-ar
422NM		= llvm-nm
423OBJCOPY		= llvm-objcopy
424OBJDUMP		= llvm-objdump
425READELF		= llvm-readelf
426OBJSIZE		= llvm-size
427STRIP		= llvm-strip
428else
429CC		= $(CROSS_COMPILE)gcc
430LD		= $(CROSS_COMPILE)ld
431AR		= $(CROSS_COMPILE)ar
432NM		= $(CROSS_COMPILE)nm
433OBJCOPY		= $(CROSS_COMPILE)objcopy
434OBJDUMP		= $(CROSS_COMPILE)objdump
435READELF		= $(CROSS_COMPILE)readelf
436OBJSIZE		= $(CROSS_COMPILE)size
437STRIP		= $(CROSS_COMPILE)strip
438endif
439PAHOLE		= pahole
440LEX		= flex
441YACC		= bison
442AWK		= awk
443INSTALLKERNEL  := installkernel
444DEPMOD		= /sbin/depmod
445PERL		= perl
446PYTHON		= python
447PYTHON3		= python3
448CHECK		= sparse
449BASH		= bash
450
451CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
452		  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
453NOSTDINC_FLAGS :=
454CFLAGS_MODULE   =
455AFLAGS_MODULE   =
456LDFLAGS_MODULE  =
457CFLAGS_KERNEL	=
458AFLAGS_KERNEL	=
459LDFLAGS_vmlinux =
460
461# Use USERINCLUDE when you must reference the UAPI directories only.
462USERINCLUDE    := \
463		-I$(srctree)/arch/$(SRCARCH)/include/uapi \
464		-I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
465		-I$(srctree)/include/uapi \
466		-I$(objtree)/include/generated/uapi \
467                -include $(srctree)/include/linux/kconfig.h
468
469# Use LINUXINCLUDE when you must reference the include/ directory.
470# Needed to be compatible with the O= option
471LINUXINCLUDE    := \
472		-I$(srctree)/arch/$(SRCARCH)/include \
473		-I$(objtree)/arch/$(SRCARCH)/include/generated \
474		$(if $(building_out_of_srctree),-I$(srctree)/include) \
475		-I$(objtree)/include \
476		$(USERINCLUDE)
477
478KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
479KBUILD_CFLAGS   := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
480		   -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
481		   -Werror=implicit-function-declaration -Werror=implicit-int \
482		   -Wno-format-security \
483		   -std=gnu89
484KBUILD_CPPFLAGS := -D__KERNEL__
485KBUILD_AFLAGS_KERNEL :=
486KBUILD_CFLAGS_KERNEL :=
487KBUILD_AFLAGS_MODULE  := -DMODULE
488KBUILD_CFLAGS_MODULE  := -DMODULE
489KBUILD_LDFLAGS_MODULE :=
490export KBUILD_LDS_MODULE := $(srctree)/scripts/module-common.lds
491KBUILD_LDFLAGS :=
492GCC_PLUGINS_CFLAGS :=
493CLANG_FLAGS :=
494
495export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC
496export CPP AR NM STRIP OBJCOPY OBJDUMP OBJSIZE READELF PAHOLE LEX YACC AWK INSTALLKERNEL
497export PERL PYTHON PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
498export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
499
500export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
501export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
502export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN
503export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
504export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
505export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
506
507# Files to ignore in find ... statements
508
509export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
510			  -name CVS -o -name .pc -o -name .hg -o -name .git \) \
511			  -prune -o
512export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
513			 --exclude CVS --exclude .pc --exclude .hg --exclude .git
514
515# ===========================================================================
516# Rules shared between *config targets and build targets
517
518# Basic helpers built in scripts/basic/
519PHONY += scripts_basic
520scripts_basic:
521	$(Q)$(MAKE) $(build)=scripts/basic
522	$(Q)rm -f .tmp_quiet_recordmcount
523
524PHONY += outputmakefile
525# Before starting out-of-tree build, make sure the source tree is clean.
526# outputmakefile generates a Makefile in the output directory, if using a
527# separate output directory. This allows convenient use of make in the
528# output directory.
529# At the same time when output Makefile generated, generate .gitignore to
530# ignore whole output directory
531outputmakefile:
532ifdef building_out_of_srctree
533	$(Q)if [ -f $(srctree)/.config -o \
534		 -d $(srctree)/include/config -o \
535		 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
536		echo >&2 "***"; \
537		echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
538		echo >&2 "*** in $(abs_srctree)";\
539		echo >&2 "***"; \
540		false; \
541	fi
542	$(Q)ln -fsn $(srctree) source
543	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile $(srctree)
544	$(Q)test -e .gitignore || \
545	{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
546endif
547
548ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),)
549ifneq ($(CROSS_COMPILE),)
550CLANG_FLAGS	+= --target=$(notdir $(CROSS_COMPILE:%-=%))
551GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
552CLANG_FLAGS	+= --prefix=$(GCC_TOOLCHAIN_DIR)
553GCC_TOOLCHAIN	:= $(realpath $(GCC_TOOLCHAIN_DIR)/..)
554endif
555ifneq ($(GCC_TOOLCHAIN),)
556CLANG_FLAGS	+= --gcc-toolchain=$(GCC_TOOLCHAIN)
557endif
558ifneq ($(LLVM_IAS),1)
559CLANG_FLAGS	+= -no-integrated-as
560endif
561CLANG_FLAGS	+= -Werror=unknown-warning-option
562KBUILD_CFLAGS	+= $(CLANG_FLAGS)
563KBUILD_AFLAGS	+= $(CLANG_FLAGS)
564export CLANG_FLAGS
565endif
566
567# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
568# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
569# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
570# and from include/config/auto.conf.cmd to detect the compiler upgrade.
571CC_VERSION_TEXT = $(shell $(CC) --version 2>/dev/null | head -n 1)
572
573ifdef config-build
574# ===========================================================================
575# *config targets only - make sure prerequisites are updated, and descend
576# in scripts/kconfig to make the *config target
577
578# Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
579# KBUILD_DEFCONFIG may point out an alternative default configuration
580# used for 'make defconfig'
581include arch/$(SRCARCH)/Makefile
582export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
583
584config: outputmakefile scripts_basic FORCE
585	$(Q)$(MAKE) $(build)=scripts/kconfig $@
586
587%config: outputmakefile scripts_basic FORCE
588	$(Q)$(MAKE) $(build)=scripts/kconfig $@
589
590else #!config-build
591# ===========================================================================
592# Build targets only - this includes vmlinux, arch specific targets, clean
593# targets and others. In general all targets except *config targets.
594
595# If building an external module we do not care about the all: rule
596# but instead _all depend on modules
597PHONY += all
598ifeq ($(KBUILD_EXTMOD),)
599_all: all
600else
601_all: modules
602endif
603
604# Decide whether to build built-in, modular, or both.
605# Normally, just do built-in.
606
607KBUILD_MODULES :=
608KBUILD_BUILTIN := 1
609
610# If we have only "make modules", don't compile built-in objects.
611# When we're building modules with modversions, we need to consider
612# the built-in objects during the descend as well, in order to
613# make sure the checksums are up to date before we record them.
614
615ifeq ($(MAKECMDGOALS),modules)
616  KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
617endif
618
619# If we have "make <whatever> modules", compile modules
620# in addition to whatever we do anyway.
621# Just "make" or "make all" shall build modules as well
622
623ifneq ($(filter all _all modules nsdeps,$(MAKECMDGOALS)),)
624  KBUILD_MODULES := 1
625endif
626
627ifeq ($(MAKECMDGOALS),)
628  KBUILD_MODULES := 1
629endif
630
631export KBUILD_MODULES KBUILD_BUILTIN
632
633ifdef need-config
634include include/config/auto.conf
635endif
636
637ifeq ($(KBUILD_EXTMOD),)
638# Objects we will link into vmlinux / subdirs we need to visit
639init-y		:= init/
640drivers-y	:= drivers/ sound/
641drivers-$(CONFIG_SAMPLES) += samples/
642net-y		:= net/
643libs-y		:= lib/
644core-y		:= usr/
645virt-y		:= virt/
646endif # KBUILD_EXTMOD
647
648# The all: target is the default when no target is given on the
649# command line.
650# This allow a user to issue only 'make' to build a kernel including modules
651# Defaults to vmlinux, but the arch makefile usually adds further targets
652all: vmlinux
653
654CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage \
655	$(call cc-option,-fno-tree-loop-im) \
656	$(call cc-disable-warning,maybe-uninitialized,)
657export CFLAGS_GCOV
658
659# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
660ifdef CONFIG_FUNCTION_TRACER
661  CC_FLAGS_FTRACE := -pg
662endif
663
664RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
665RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
666RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
667RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
668RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
669RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
670export RETPOLINE_CFLAGS
671export RETPOLINE_VDSO_CFLAGS
672
673include arch/$(SRCARCH)/Makefile
674
675ifdef need-config
676ifdef may-sync-config
677# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
678# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
679# because some architectures define CROSS_COMPILE there.
680include include/config/auto.conf.cmd
681
682$(KCONFIG_CONFIG):
683	@echo >&2 '***'
684	@echo >&2 '*** Configuration file "$@" not found!'
685	@echo >&2 '***'
686	@echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
687	@echo >&2 '*** "make menuconfig" or "make xconfig").'
688	@echo >&2 '***'
689	@/bin/false
690
691# The actual configuration files used during the build are stored in
692# include/generated/ and include/config/. Update them if .config is newer than
693# include/config/auto.conf (which mirrors .config).
694#
695# This exploits the 'multi-target pattern rule' trick.
696# The syncconfig should be executed only once to make all the targets.
697# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
698%/auto.conf %/auto.conf.cmd: $(KCONFIG_CONFIG)
699	$(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
700else # !may-sync-config
701# External modules and some install targets need include/generated/autoconf.h
702# and include/config/auto.conf but do not care if they are up-to-date.
703# Use auto.conf to trigger the test
704PHONY += include/config/auto.conf
705
706include/config/auto.conf:
707	$(Q)test -e include/generated/autoconf.h -a -e $@ || (		\
708	echo >&2;							\
709	echo >&2 "  ERROR: Kernel configuration is invalid.";		\
710	echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
711	echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";	\
712	echo >&2 ;							\
713	/bin/false)
714
715endif # may-sync-config
716endif # need-config
717
718KBUILD_CFLAGS	+= $(call cc-option,-fno-delete-null-pointer-checks,)
719KBUILD_CFLAGS	+= $(call cc-disable-warning,frame-address,)
720KBUILD_CFLAGS	+= $(call cc-disable-warning, format-truncation)
721KBUILD_CFLAGS	+= $(call cc-disable-warning, format-overflow)
722KBUILD_CFLAGS	+= $(call cc-disable-warning, address-of-packed-member)
723
724ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
725KBUILD_CFLAGS += -O2
726else ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3
727KBUILD_CFLAGS += -O3
728else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
729KBUILD_CFLAGS += -Os
730endif
731
732# Tell gcc to never replace conditional load with a non-conditional one
733KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
734KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
735
736include scripts/Makefile.kcov
737include scripts/Makefile.gcc-plugins
738
739ifdef CONFIG_READABLE_ASM
740# Disable optimizations that make assembler listings hard to read.
741# reorder blocks reorders the control in the function
742# ipa clone creates specialized cloned functions
743# partial inlining inlines only parts of functions
744KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
745                 $(call cc-option,-fno-ipa-cp-clone,) \
746                 $(call cc-option,-fno-partial-inlining)
747endif
748
749ifneq ($(CONFIG_FRAME_WARN),0)
750KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
751endif
752
753stackp-flags-$(CONFIG_CC_HAS_STACKPROTECTOR_NONE) := -fno-stack-protector
754stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
755stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
756
757KBUILD_CFLAGS += $(stackp-flags-y)
758
759ifdef CONFIG_CC_IS_CLANG
760KBUILD_CPPFLAGS += -Qunused-arguments
761KBUILD_CFLAGS += -Wno-format-invalid-specifier
762KBUILD_CFLAGS += -Wno-gnu
763# CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
764# source of a reference will be _MergedGlobals and not on of the whitelisted names.
765# See modpost pattern 2
766KBUILD_CFLAGS += -mno-global-merge
767else
768
769# These warnings generated too much noise in a regular build.
770# Use make W=1 to enable them (see scripts/Makefile.extrawarn)
771KBUILD_CFLAGS += -Wno-unused-but-set-variable
772
773# Warn about unmarked fall-throughs in switch statement.
774# Disabled for clang while comment to attribute conversion happens and
775# https://github.com/ClangBuiltLinux/linux/issues/636 is discussed.
776KBUILD_CFLAGS += $(call cc-option,-Wimplicit-fallthrough,)
777endif
778
779KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
780ifdef CONFIG_FRAME_POINTER
781KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
782else
783# Some targets (ARM with Thumb2, for example), can't be built with frame
784# pointers.  For those, we don't have FUNCTION_TRACER automatically
785# select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
786# incompatible with -fomit-frame-pointer with current GCC, so we don't use
787# -fomit-frame-pointer with FUNCTION_TRACER.
788ifndef CONFIG_FUNCTION_TRACER
789KBUILD_CFLAGS	+= -fomit-frame-pointer
790endif
791endif
792
793# Initialize all stack variables with a pattern, if desired.
794ifdef CONFIG_INIT_STACK_ALL
795KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
796endif
797
798DEBUG_CFLAGS	:= $(call cc-option, -fno-var-tracking-assignments)
799
800ifdef CONFIG_DEBUG_INFO
801ifdef CONFIG_DEBUG_INFO_SPLIT
802DEBUG_CFLAGS	+= -gsplit-dwarf
803else
804DEBUG_CFLAGS	+= -g
805endif
806KBUILD_AFLAGS	+= -Wa,-gdwarf-2
807endif
808ifdef CONFIG_DEBUG_INFO_DWARF4
809DEBUG_CFLAGS	+= -gdwarf-4
810endif
811
812ifdef CONFIG_DEBUG_INFO_REDUCED
813DEBUG_CFLAGS	+= $(call cc-option, -femit-struct-debug-baseonly) \
814		   $(call cc-option,-fno-var-tracking)
815endif
816
817KBUILD_CFLAGS += $(DEBUG_CFLAGS)
818export DEBUG_CFLAGS
819
820ifdef CONFIG_FUNCTION_TRACER
821ifdef CONFIG_FTRACE_MCOUNT_RECORD
822  # gcc 5 supports generating the mcount tables directly
823  ifeq ($(call cc-option-yn,-mrecord-mcount),y)
824    CC_FLAGS_FTRACE	+= -mrecord-mcount
825    export CC_USING_RECORD_MCOUNT := 1
826  endif
827  ifdef CONFIG_HAVE_NOP_MCOUNT
828    ifeq ($(call cc-option-yn, -mnop-mcount),y)
829      CC_FLAGS_FTRACE	+= -mnop-mcount
830      CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
831    endif
832  endif
833endif
834ifdef CONFIG_HAVE_FENTRY
835  ifeq ($(call cc-option-yn, -mfentry),y)
836    CC_FLAGS_FTRACE	+= -mfentry
837    CC_FLAGS_USING	+= -DCC_USING_FENTRY
838  endif
839endif
840export CC_FLAGS_FTRACE
841KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
842KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
843ifdef CONFIG_DYNAMIC_FTRACE
844	ifdef CONFIG_HAVE_C_RECORDMCOUNT
845		BUILD_C_RECORDMCOUNT := y
846		export BUILD_C_RECORDMCOUNT
847	endif
848endif
849endif
850
851# We trigger additional mismatches with less inlining
852ifdef CONFIG_DEBUG_SECTION_MISMATCH
853KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
854endif
855
856ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
857KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
858LDFLAGS_vmlinux += --gc-sections
859endif
860
861ifdef CONFIG_LIVEPATCH
862KBUILD_CFLAGS += $(call cc-option, -flive-patching=inline-clone)
863endif
864
865# arch Makefile may override CC so keep this after arch Makefile is included
866NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
867
868# warn about C99 declaration after statement
869KBUILD_CFLAGS += -Wdeclaration-after-statement
870
871# Variable Length Arrays (VLAs) should not be used anywhere in the kernel
872KBUILD_CFLAGS += -Wvla
873
874# disable pointer signed / unsigned warnings in gcc 4.0
875KBUILD_CFLAGS += -Wno-pointer-sign
876
877# disable stringop warnings in gcc 8+
878KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
879
880# We'll want to enable this eventually, but it's not going away for 5.7 at least
881KBUILD_CFLAGS += $(call cc-disable-warning, zero-length-bounds)
882KBUILD_CFLAGS += $(call cc-disable-warning, array-bounds)
883KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
884
885# Another good warning that we'll want to enable eventually
886KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
887
888# Enabled with W=2, disabled by default as noisy
889KBUILD_CFLAGS += $(call cc-disable-warning, maybe-uninitialized)
890
891# disable invalid "can't wrap" optimizations for signed / pointers
892KBUILD_CFLAGS	+= $(call cc-option,-fno-strict-overflow)
893
894# clang sets -fmerge-all-constants by default as optimization, but this
895# is non-conforming behavior for C and in fact breaks the kernel, so we
896# need to disable it here generally.
897KBUILD_CFLAGS	+= $(call cc-option,-fno-merge-all-constants)
898
899# for gcc -fno-merge-all-constants disables everything, but it is fine
900# to have actual conforming behavior enabled.
901KBUILD_CFLAGS	+= $(call cc-option,-fmerge-constants)
902
903# Make sure -fstack-check isn't enabled (like gentoo apparently did)
904KBUILD_CFLAGS  += $(call cc-option,-fno-stack-check,)
905
906# conserve stack if available
907KBUILD_CFLAGS   += $(call cc-option,-fconserve-stack)
908
909# Prohibit date/time macros, which would make the build non-deterministic
910KBUILD_CFLAGS   += $(call cc-option,-Werror=date-time)
911
912# enforce correct pointer usage
913KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)
914
915# Require designated initializers for all marked structures
916KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)
917
918# change __FILE__ to the relative path from the srctree
919KBUILD_CFLAGS	+= $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
920
921# ensure -fcf-protection is disabled when using retpoline as it is
922# incompatible with -mindirect-branch=thunk-extern
923ifdef CONFIG_RETPOLINE
924KBUILD_CFLAGS += $(call cc-option,-fcf-protection=none)
925endif
926
927include scripts/Makefile.kasan
928include scripts/Makefile.extrawarn
929include scripts/Makefile.ubsan
930
931# Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
932KBUILD_CPPFLAGS += $(KCPPFLAGS)
933KBUILD_AFLAGS   += $(KAFLAGS)
934KBUILD_CFLAGS   += $(KCFLAGS)
935
936KBUILD_LDFLAGS_MODULE += --build-id
937LDFLAGS_vmlinux += --build-id
938
939ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
940LDFLAGS_vmlinux	+= $(call ld-option, -X,)
941endif
942
943ifeq ($(CONFIG_RELR),y)
944LDFLAGS_vmlinux	+= --pack-dyn-relocs=relr
945endif
946
947# make the checker run with the right architecture
948CHECKFLAGS += --arch=$(ARCH)
949
950# insure the checker run with the right endianness
951CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
952
953# the checker needs the correct machine size
954CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
955
956# Default kernel image to build when no specific target is given.
957# KBUILD_IMAGE may be overruled on the command line or
958# set in the environment
959# Also any assignments in arch/$(ARCH)/Makefile take precedence over
960# this default value
961export KBUILD_IMAGE ?= vmlinux
962
963#
964# INSTALL_PATH specifies where to place the updated kernel and system map
965# images. Default is /boot, but you can set it to other values
966export	INSTALL_PATH ?= /boot
967
968#
969# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
970# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
971# an argument if needed. Otherwise it defaults to the kernel install path
972#
973export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
974
975#
976# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
977# relocations required by build roots.  This is not defined in the
978# makefile but the argument can be passed to make if needed.
979#
980
981MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
982export MODLIB
983
984#
985# INSTALL_MOD_STRIP, if defined, will cause modules to be
986# stripped after they are installed.  If INSTALL_MOD_STRIP is '1', then
987# the default option --strip-debug will be used.  Otherwise,
988# INSTALL_MOD_STRIP value will be used as the options to the strip command.
989
990ifdef INSTALL_MOD_STRIP
991ifeq ($(INSTALL_MOD_STRIP),1)
992mod_strip_cmd = $(STRIP) --strip-debug
993else
994mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
995endif # INSTALL_MOD_STRIP=1
996else
997mod_strip_cmd = true
998endif # INSTALL_MOD_STRIP
999export mod_strip_cmd
1000
1001# CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
1002# after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
1003# or CONFIG_MODULE_COMPRESS_XZ.
1004
1005mod_compress_cmd = true
1006ifdef CONFIG_MODULE_COMPRESS
1007  ifdef CONFIG_MODULE_COMPRESS_GZIP
1008    mod_compress_cmd = gzip -n -f
1009  endif # CONFIG_MODULE_COMPRESS_GZIP
1010  ifdef CONFIG_MODULE_COMPRESS_XZ
1011    mod_compress_cmd = xz -f
1012  endif # CONFIG_MODULE_COMPRESS_XZ
1013endif # CONFIG_MODULE_COMPRESS
1014export mod_compress_cmd
1015
1016ifdef CONFIG_MODULE_SIG_ALL
1017$(eval $(call config_filename,MODULE_SIG_KEY))
1018
1019mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
1020else
1021mod_sign_cmd = true
1022endif
1023export mod_sign_cmd
1024
1025HOST_LIBELF_LIBS = $(shell pkg-config libelf --libs 2>/dev/null || echo -lelf)
1026
1027ifdef CONFIG_STACK_VALIDATION
1028  has_libelf := $(call try-run,\
1029		echo "int main() {}" | $(HOSTCC) -xc -o /dev/null $(HOST_LIBELF_LIBS) -,1,0)
1030  ifeq ($(has_libelf),1)
1031    objtool_target := tools/objtool FORCE
1032  else
1033    SKIP_STACK_VALIDATION := 1
1034    export SKIP_STACK_VALIDATION
1035  endif
1036endif
1037
1038PHONY += prepare0
1039
1040export MODORDER := $(extmod-prefix)modules.order
1041export MODULES_NSDEPS := $(extmod-prefix)modules.nsdeps
1042
1043ifeq ($(KBUILD_EXTMOD),)
1044core-y		+= kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
1045
1046vmlinux-dirs	:= $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
1047		     $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
1048		     $(net-y) $(net-m) $(libs-y) $(libs-m) $(virt-y)))
1049
1050vmlinux-alldirs	:= $(sort $(vmlinux-dirs) Documentation \
1051		     $(patsubst %/,%,$(filter %/, $(init-) $(core-) \
1052			$(drivers-) $(net-) $(libs-) $(virt-))))
1053
1054build-dirs	:= $(vmlinux-dirs)
1055clean-dirs	:= $(vmlinux-alldirs)
1056
1057init-y		:= $(patsubst %/, %/built-in.a, $(init-y))
1058core-y		:= $(patsubst %/, %/built-in.a, $(core-y))
1059drivers-y	:= $(patsubst %/, %/built-in.a, $(drivers-y))
1060net-y		:= $(patsubst %/, %/built-in.a, $(net-y))
1061libs-y2		:= $(patsubst %/, %/built-in.a, $(filter %/, $(libs-y)))
1062ifdef CONFIG_MODULES
1063libs-y1		:= $(filter-out %/, $(libs-y))
1064libs-y2		+= $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1065else
1066libs-y1		:= $(patsubst %/, %/lib.a, $(libs-y))
1067endif
1068virt-y		:= $(patsubst %/, %/built-in.a, $(virt-y))
1069
1070# Externally visible symbols (used by link-vmlinux.sh)
1071export KBUILD_VMLINUX_OBJS := $(head-y) $(init-y) $(core-y) $(libs-y2) \
1072			      $(drivers-y) $(net-y) $(virt-y)
1073export KBUILD_VMLINUX_LIBS := $(libs-y1)
1074export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1075export LDFLAGS_vmlinux
1076# used by scripts/Makefile.package
1077export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) LICENSES arch include scripts tools)
1078
1079vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
1080
1081# Recurse until adjust_autoksyms.sh is satisfied
1082PHONY += autoksyms_recursive
1083ifdef CONFIG_TRIM_UNUSED_KSYMS
1084autoksyms_recursive: descend modules.order
1085	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1086	  "$(MAKE) -f $(srctree)/Makefile vmlinux"
1087endif
1088
1089# For the kernel to actually contain only the needed exported symbols,
1090# we have to build modules as well to determine what those symbols are.
1091# (this can be evaluated only once include/config/auto.conf has been included)
1092ifdef CONFIG_TRIM_UNUSED_KSYMS
1093  KBUILD_MODULES := 1
1094endif
1095
1096autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1097
1098quiet_cmd_autoksyms_h = GEN     $@
1099      cmd_autoksyms_h = mkdir -p $(dir $@); \
1100			$(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@
1101
1102$(autoksyms_h):
1103	$(call cmd,autoksyms_h)
1104
1105ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1106
1107# Final link of vmlinux with optional arch pass after final link
1108cmd_link-vmlinux =                                                 \
1109	$(CONFIG_SHELL) $< $(LD) $(KBUILD_LDFLAGS) $(LDFLAGS_vmlinux) ;    \
1110	$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1111
1112vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1113	+$(call if_changed,link-vmlinux)
1114
1115targets := vmlinux
1116
1117# The actual objects are generated when descending,
1118# make sure no implicit rule kicks in
1119$(sort $(vmlinux-deps)): descend ;
1120
1121filechk_kernel.release = \
1122	echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1123
1124# Store (new) KERNELRELEASE string in include/config/kernel.release
1125include/config/kernel.release: FORCE
1126	$(call filechk,kernel.release)
1127
1128# Additional helpers built in scripts/
1129# Carefully list dependencies so we do not try to build scripts twice
1130# in parallel
1131PHONY += scripts
1132scripts: scripts_basic scripts_dtc
1133	$(Q)$(MAKE) $(build)=$(@)
1134
1135# Things we need to do before we recursively start building the kernel
1136# or the modules are listed in "prepare".
1137# A multi level approach is used. prepareN is processed before prepareN-1.
1138# archprepare is used in arch Makefiles and when processed asm symlink,
1139# version.h and scripts_basic is processed / created.
1140
1141PHONY += prepare archprepare
1142
1143archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1144	asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h
1145
1146prepare0: archprepare
1147	$(Q)$(MAKE) $(build)=scripts/mod
1148	$(Q)$(MAKE) $(build)=.
1149
1150# All the preparing..
1151prepare: prepare0 prepare-objtool
1152
1153# Support for using generic headers in asm-generic
1154asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1155
1156PHONY += asm-generic uapi-asm-generic
1157asm-generic: uapi-asm-generic
1158	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1159	generic=include/asm-generic
1160uapi-asm-generic:
1161	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1162	generic=include/uapi/asm-generic
1163
1164PHONY += prepare-objtool
1165prepare-objtool: $(objtool_target)
1166ifeq ($(SKIP_STACK_VALIDATION),1)
1167ifdef CONFIG_UNWINDER_ORC
1168	@echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1169	@false
1170else
1171	@echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1172endif
1173endif
1174
1175# Generate some files
1176# ---------------------------------------------------------------------------
1177
1178# KERNELRELEASE can change from a few different places, meaning version.h
1179# needs to be updated, so this check is forced on all builds
1180
1181uts_len := 64
1182define filechk_utsrelease.h
1183	if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1184	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1185	  exit 1;                                                         \
1186	fi;                                                               \
1187	echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1188endef
1189
1190define filechk_version.h
1191	echo \#define LINUX_VERSION_CODE $(shell                         \
1192	expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1193	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))'
1194endef
1195
1196$(version_h): FORCE
1197	$(call filechk,version.h)
1198	$(Q)rm -f $(old_version_h)
1199
1200include/generated/utsrelease.h: include/config/kernel.release FORCE
1201	$(call filechk,utsrelease.h)
1202
1203PHONY += headerdep
1204headerdep:
1205	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1206	$(srctree)/scripts/headerdep.pl -I$(srctree)/include
1207
1208# ---------------------------------------------------------------------------
1209# Kernel headers
1210
1211#Default location for installed headers
1212export INSTALL_HDR_PATH = $(objtree)/usr
1213
1214quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1215      cmd_headers_install = \
1216	mkdir -p $(INSTALL_HDR_PATH); \
1217	rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1218	usr/include $(INSTALL_HDR_PATH)
1219
1220PHONY += headers_install
1221headers_install: headers
1222	$(call cmd,headers_install)
1223
1224PHONY += archheaders archscripts
1225
1226hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1227
1228PHONY += headers
1229headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1230	$(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1231	  $(error Headers not exportable for the $(SRCARCH) architecture))
1232	$(Q)$(MAKE) $(hdr-inst)=include/uapi
1233	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1234
1235# Deprecated. It is no-op now.
1236PHONY += headers_check
1237headers_check:
1238	@:
1239
1240ifdef CONFIG_HEADERS_INSTALL
1241prepare: headers
1242endif
1243
1244PHONY += scripts_unifdef
1245scripts_unifdef: scripts_basic
1246	$(Q)$(MAKE) $(build)=scripts scripts/unifdef
1247
1248# ---------------------------------------------------------------------------
1249# Kernel selftest
1250
1251PHONY += kselftest
1252kselftest:
1253	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1254
1255kselftest-%: FORCE
1256	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1257
1258PHONY += kselftest-merge
1259kselftest-merge:
1260	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1261	$(Q)find $(srctree)/tools/testing/selftests -name config | \
1262		xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1263	$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1264
1265# ---------------------------------------------------------------------------
1266# Devicetree files
1267
1268ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1269dtstree := arch/$(SRCARCH)/boot/dts
1270endif
1271
1272ifneq ($(dtstree),)
1273
1274%.dtb: include/config/kernel.release scripts_dtc
1275	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1276
1277PHONY += dtbs dtbs_install dtbs_check
1278dtbs: include/config/kernel.release scripts_dtc
1279	$(Q)$(MAKE) $(build)=$(dtstree)
1280
1281ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1282export CHECK_DTBS=y
1283dtbs: dt_binding_check
1284endif
1285
1286dtbs_check: dtbs
1287
1288dtbs_install:
1289	$(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1290
1291ifdef CONFIG_OF_EARLY_FLATTREE
1292all: dtbs
1293endif
1294
1295endif
1296
1297PHONY += scripts_dtc
1298scripts_dtc: scripts_basic
1299	$(Q)$(MAKE) $(build)=scripts/dtc
1300
1301ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1302export CHECK_DT_BINDING=y
1303endif
1304
1305PHONY += dt_binding_check
1306dt_binding_check: scripts_dtc
1307	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1308
1309# ---------------------------------------------------------------------------
1310# Modules
1311
1312ifdef CONFIG_MODULES
1313
1314# By default, build modules as well
1315
1316all: modules
1317
1318# Build modules
1319#
1320# A module can be listed more than once in obj-m resulting in
1321# duplicate lines in modules.order files.  Those are removed
1322# using awk while concatenating to the final file.
1323
1324PHONY += modules
1325modules: $(if $(KBUILD_BUILTIN),vmlinux) modules.order
1326	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1327	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh
1328
1329modules.order: descend
1330	$(Q)$(AWK) '!x[$$0]++' $(addsuffix /$@, $(build-dirs)) > $@
1331
1332# Target to prepare building external modules
1333PHONY += modules_prepare
1334modules_prepare: prepare
1335
1336# Target to install modules
1337PHONY += modules_install
1338modules_install: _modinst_ _modinst_post
1339
1340PHONY += _modinst_
1341_modinst_:
1342	@rm -rf $(MODLIB)/kernel
1343	@rm -f $(MODLIB)/source
1344	@mkdir -p $(MODLIB)/kernel
1345	@ln -s $(abspath $(srctree)) $(MODLIB)/source
1346	@if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
1347		rm -f $(MODLIB)/build ; \
1348		ln -s $(CURDIR) $(MODLIB)/build ; \
1349	fi
1350	@sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order
1351	@cp -f modules.builtin $(MODLIB)/
1352	@cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
1353	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1354
1355# This depmod is only for convenience to give the initial
1356# boot a modules.dep even before / is mounted read-write.  However the
1357# boot script depmod is the master version.
1358PHONY += _modinst_post
1359_modinst_post: _modinst_
1360	$(call cmd,depmod)
1361
1362ifeq ($(CONFIG_MODULE_SIG), y)
1363PHONY += modules_sign
1364modules_sign:
1365	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1366endif
1367
1368else # CONFIG_MODULES
1369
1370# Modules not configured
1371# ---------------------------------------------------------------------------
1372
1373PHONY += modules modules_install
1374modules modules_install:
1375	@echo >&2
1376	@echo >&2 "The present kernel configuration has modules disabled."
1377	@echo >&2 "Type 'make config' and enable loadable module support."
1378	@echo >&2 "Then build a kernel with module support enabled."
1379	@echo >&2
1380	@exit 1
1381
1382endif # CONFIG_MODULES
1383
1384###
1385# Cleaning is done on three levels.
1386# make clean     Delete most generated files
1387#                Leave enough to build external modules
1388# make mrproper  Delete the current configuration, and all generated files
1389# make distclean Remove editor backup files, patch leftover files and the like
1390
1391# Directories & files removed with 'make clean'
1392CLEAN_DIRS  += include/ksym
1393CLEAN_FILES += modules.builtin modules.builtin.modinfo modules.nsdeps
1394
1395# Directories & files removed with 'make mrproper'
1396MRPROPER_DIRS  += include/config include/generated          \
1397		  arch/$(SRCARCH)/include/generated .tmp_objdiff \
1398		  debian/ snap/ tar-install/
1399MRPROPER_FILES += .config .config.old .version \
1400		  Module.symvers \
1401		  signing_key.pem signing_key.priv signing_key.x509	\
1402		  x509.genkey extra_certificates signing_key.x509.keyid	\
1403		  signing_key.x509.signer vmlinux-gdb.py \
1404		  *.spec
1405
1406# Directories & files removed with 'make distclean'
1407DISTCLEAN_DIRS  +=
1408DISTCLEAN_FILES += tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS
1409
1410# clean - Delete most, but leave enough to build external modules
1411#
1412clean: rm-dirs  := $(CLEAN_DIRS)
1413clean: rm-files := $(CLEAN_FILES)
1414
1415PHONY += archclean vmlinuxclean
1416
1417vmlinuxclean:
1418	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1419	$(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1420
1421clean: archclean vmlinuxclean
1422
1423# mrproper - Delete all generated files, including .config
1424#
1425mrproper: rm-dirs  := $(wildcard $(MRPROPER_DIRS))
1426mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1427mrproper-dirs      := $(addprefix _mrproper_,scripts)
1428
1429PHONY += $(mrproper-dirs) mrproper
1430$(mrproper-dirs):
1431	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1432
1433mrproper: clean $(mrproper-dirs)
1434	$(call cmd,rmdirs)
1435	$(call cmd,rmfiles)
1436
1437# distclean
1438#
1439distclean: rm-dirs  := $(wildcard $(DISTCLEAN_DIRS))
1440distclean: rm-files := $(wildcard $(DISTCLEAN_FILES))
1441
1442PHONY += distclean
1443
1444distclean: mrproper
1445	$(call cmd,rmdirs)
1446	$(call cmd,rmfiles)
1447	@find $(srctree) $(RCS_FIND_IGNORE) \
1448		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1449		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
1450		-o -name 'core' \) \
1451		-type f -print | xargs rm -f
1452
1453
1454# Packaging of the kernel to various formats
1455# ---------------------------------------------------------------------------
1456
1457%src-pkg: FORCE
1458	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1459%pkg: include/config/kernel.release FORCE
1460	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1461
1462# Brief documentation of the typical targets used
1463# ---------------------------------------------------------------------------
1464
1465boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1466boards := $(sort $(notdir $(boards)))
1467board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1468board-dirs := $(sort $(notdir $(board-dirs:/=)))
1469
1470PHONY += help
1471help:
1472	@echo  'Cleaning targets:'
1473	@echo  '  clean		  - Remove most generated files but keep the config and'
1474	@echo  '                    enough build support to build external modules'
1475	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
1476	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
1477	@echo  ''
1478	@echo  'Configuration targets:'
1479	@$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1480	@echo  ''
1481	@echo  'Other generic targets:'
1482	@echo  '  all		  - Build all targets marked with [*]'
1483	@echo  '* vmlinux	  - Build the bare kernel'
1484	@echo  '* modules	  - Build all modules'
1485	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1486	@echo  '  dir/            - Build all files in dir and below'
1487	@echo  '  dir/file.[ois]  - Build specified target only'
1488	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1489	@echo  '                    (requires compiler support for LLVM assembly generation)'
1490	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1491	@echo  '                    (requires a recent binutils and recent build (System.map))'
1492	@echo  '  dir/file.ko     - Build module including final link'
1493	@echo  '  modules_prepare - Set up for building external modules'
1494	@echo  '  tags/TAGS	  - Generate tags file for editors'
1495	@echo  '  cscope	  - Generate cscope index'
1496	@echo  '  gtags           - Generate GNU GLOBAL index'
1497	@echo  '  kernelrelease	  - Output the release version string (use with make -s)'
1498	@echo  '  kernelversion	  - Output the version stored in Makefile (use with make -s)'
1499	@echo  '  image_name	  - Output the image name (use with make -s)'
1500	@echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1501	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1502	 echo  ''
1503	@echo  'Static analysers:'
1504	@echo  '  checkstack      - Generate a list of stack hogs'
1505	@echo  '  namespacecheck  - Name space analysis on compiled kernel'
1506	@echo  '  versioncheck    - Sanity check on version.h usage'
1507	@echo  '  includecheck    - Check for duplicate included header files'
1508	@echo  '  export_report   - List the usages of all exported symbols'
1509	@echo  '  headerdep       - Detect inclusion cycles in headers'
1510	@echo  '  coccicheck      - Check with Coccinelle'
1511	@echo  ''
1512	@echo  'Tools:'
1513	@echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1514	@echo  ''
1515	@echo  'Kernel selftest:'
1516	@echo  '  kselftest         - Build and run kernel selftest'
1517	@echo  '                      Build, install, and boot kernel before'
1518	@echo  '                      running kselftest on it'
1519	@echo  '                      Run as root for full coverage'
1520	@echo  '  kselftest-all     - Build kernel selftest'
1521	@echo  '  kselftest-install - Build and install kernel selftest'
1522	@echo  '  kselftest-clean   - Remove all generated kselftest files'
1523	@echo  '  kselftest-merge   - Merge all the config dependencies of'
1524	@echo  '		      kselftest to existing .config.'
1525	@echo  ''
1526	@$(if $(dtstree), \
1527		echo 'Devicetree:'; \
1528		echo '* dtbs             - Build device tree blobs for enabled boards'; \
1529		echo '  dtbs_install     - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1530		echo '  dt_binding_check - Validate device tree binding documents'; \
1531		echo '  dtbs_check       - Validate device tree source files';\
1532		echo '')
1533
1534	@echo 'Userspace tools targets:'
1535	@echo '  use "make tools/help"'
1536	@echo '  or  "cd tools; make help"'
1537	@echo  ''
1538	@echo  'Kernel packaging:'
1539	@$(MAKE) -f $(srctree)/scripts/Makefile.package help
1540	@echo  ''
1541	@echo  'Documentation targets:'
1542	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1543	@echo  ''
1544	@echo  'Architecture specific targets ($(SRCARCH)):'
1545	@$(if $(archhelp),$(archhelp),\
1546		echo '  No architecture specific help defined for $(SRCARCH)')
1547	@echo  ''
1548	@$(if $(boards), \
1549		$(foreach b, $(boards), \
1550		printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1551		echo '')
1552	@$(if $(board-dirs), \
1553		$(foreach b, $(board-dirs), \
1554		printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1555		printf "  %-16s - Show all of the above\\n" help-boards; \
1556		echo '')
1557
1558	@echo  '  make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1559	@echo  '  make V=2   [targets] 2 => give reason for rebuild of target'
1560	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1561	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1562	@echo  '                       (sparse by default)'
1563	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1564	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1565	@echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
1566	@echo  '		1: warnings which may be relevant and do not occur too often'
1567	@echo  '		2: warnings which occur quite often but may still be relevant'
1568	@echo  '		3: more obscure warnings, can most likely be ignored'
1569	@echo  '		Multiple levels can be combined with W=12 or W=123'
1570	@echo  ''
1571	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
1572	@echo  'For further info see the ./README file'
1573
1574
1575help-board-dirs := $(addprefix help-,$(board-dirs))
1576
1577help-boards: $(help-board-dirs)
1578
1579boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1580
1581$(help-board-dirs): help-%:
1582	@echo  'Architecture specific targets ($(SRCARCH) $*):'
1583	@$(if $(boards-per-dir), \
1584		$(foreach b, $(boards-per-dir), \
1585		printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1586		echo '')
1587
1588
1589# Documentation targets
1590# ---------------------------------------------------------------------------
1591DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1592	       linkcheckdocs dochelp refcheckdocs
1593PHONY += $(DOC_TARGETS)
1594$(DOC_TARGETS):
1595	$(Q)$(MAKE) $(build)=Documentation $@
1596
1597# Misc
1598# ---------------------------------------------------------------------------
1599
1600PHONY += scripts_gdb
1601scripts_gdb: prepare0
1602	$(Q)$(MAKE) $(build)=scripts/gdb
1603	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1604
1605ifdef CONFIG_GDB_SCRIPTS
1606all: scripts_gdb
1607endif
1608
1609else # KBUILD_EXTMOD
1610
1611###
1612# External module support.
1613# When building external modules the kernel used as basis is considered
1614# read-only, and no consistency checks are made and the make
1615# system is not used on the basis kernel. If updates are required
1616# in the basis kernel ordinary make commands (without M=...) must
1617# be used.
1618#
1619# The following are the only valid targets when building external
1620# modules.
1621# make M=dir clean     Delete all automatically generated files
1622# make M=dir modules   Make all modules in specified dir
1623# make M=dir	       Same as 'make M=dir modules'
1624# make M=dir modules_install
1625#                      Install the modules built in the module directory
1626#                      Assumes install directory is already created
1627
1628# We are always building modules
1629KBUILD_MODULES := 1
1630
1631PHONY += $(objtree)/Module.symvers
1632$(objtree)/Module.symvers:
1633	@test -e $(objtree)/Module.symvers || ( \
1634	echo; \
1635	echo "  WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1636	echo "           is missing; modules will have no dependencies and modversions."; \
1637	echo )
1638
1639build-dirs := $(KBUILD_EXTMOD)
1640PHONY += modules
1641modules: descend $(objtree)/Module.symvers
1642	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1643
1644PHONY += modules_install
1645modules_install: _emodinst_ _emodinst_post
1646
1647install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1648PHONY += _emodinst_
1649_emodinst_:
1650	$(Q)mkdir -p $(MODLIB)/$(install-dir)
1651	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1652
1653PHONY += _emodinst_post
1654_emodinst_post: _emodinst_
1655	$(call cmd,depmod)
1656
1657clean-dirs := $(KBUILD_EXTMOD)
1658clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps
1659
1660PHONY += /
1661/:
1662	@echo >&2 '"$(MAKE) /" is no longer supported. Please use "$(MAKE) ./" instead.'
1663
1664PHONY += help
1665help:
1666	@echo  '  Building external modules.'
1667	@echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1668	@echo  ''
1669	@echo  '  modules         - default target, build the module(s)'
1670	@echo  '  modules_install - install the module'
1671	@echo  '  clean           - remove generated files in module directory only'
1672	@echo  ''
1673
1674PHONY += prepare
1675endif # KBUILD_EXTMOD
1676
1677# Single targets
1678# ---------------------------------------------------------------------------
1679# To build individual files in subdirectories, you can do like this:
1680#
1681#   make foo/bar/baz.s
1682#
1683# The supported suffixes for single-target are listed in 'single-targets'
1684#
1685# To build only under specific subdirectories, you can do like this:
1686#
1687#   make foo/bar/baz/
1688
1689ifdef single-build
1690
1691# .ko is special because modpost is needed
1692single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1693single-no-ko := $(sort $(patsubst %.ko,%.mod, $(MAKECMDGOALS)))
1694
1695$(single-ko): single_modpost
1696	@:
1697$(single-no-ko): descend
1698	@:
1699
1700ifeq ($(KBUILD_EXTMOD),)
1701# For the single build of in-tree modules, use a temporary file to avoid
1702# the situation of modules_install installing an invalid modules.order.
1703MODORDER := .modules.tmp
1704endif
1705
1706PHONY += single_modpost
1707single_modpost: $(single-no-ko)
1708	$(Q){ $(foreach m, $(single-ko), echo $(extmod-prefix)$m;) } > $(MODORDER)
1709	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1710
1711KBUILD_MODULES := 1
1712
1713export KBUILD_SINGLE_TARGETS := $(addprefix $(extmod-prefix), $(single-no-ko))
1714
1715# trim unrelated directories
1716build-dirs := $(foreach d, $(build-dirs), \
1717			$(if $(filter $(d)/%, $(KBUILD_SINGLE_TARGETS)), $(d)))
1718
1719endif
1720
1721# Handle descending into subdirectories listed in $(build-dirs)
1722# Preset locale variables to speed up the build process. Limit locale
1723# tweaks to this spot to avoid wrong language settings when running
1724# make menuconfig etc.
1725# Error messages still appears in the original language
1726PHONY += descend $(build-dirs)
1727descend: $(build-dirs)
1728$(build-dirs): prepare
1729	$(Q)$(MAKE) $(build)=$@ \
1730	single-build=$(if $(filter-out $@/, $(filter $@/%, $(single-no-ko))),1) \
1731	need-builtin=1 need-modorder=1
1732
1733clean-dirs := $(addprefix _clean_, $(clean-dirs))
1734PHONY += $(clean-dirs) clean
1735$(clean-dirs):
1736	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1737
1738clean: $(clean-dirs)
1739	$(call cmd,rmdirs)
1740	$(call cmd,rmfiles)
1741	@find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1742		\( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1743		-o -name '*.ko.*' \
1744		-o -name '*.dtb' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1745		-o -name '*.dwo' -o -name '*.lst' \
1746		-o -name '*.su' -o -name '*.mod' \
1747		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1748		-o -name '*.lex.c' -o -name '*.tab.[ch]' \
1749		-o -name '*.asn1.[ch]' \
1750		-o -name '*.symtypes' -o -name 'modules.order' \
1751		-o -name '.tmp_*.o.*' \
1752		-o -name '*.c.[012]*.*' \
1753		-o -name '*.ll' \
1754		-o -name '*.gcno' \) -type f -print | xargs rm -f
1755
1756# Generate tags for editors
1757# ---------------------------------------------------------------------------
1758quiet_cmd_tags = GEN     $@
1759      cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1760
1761tags TAGS cscope gtags: FORCE
1762	$(call cmd,tags)
1763
1764# Script to generate missing namespace dependencies
1765# ---------------------------------------------------------------------------
1766
1767PHONY += nsdeps
1768nsdeps: export KBUILD_NSDEPS=1
1769nsdeps: modules
1770	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1771
1772# Scripts to check various things for consistency
1773# ---------------------------------------------------------------------------
1774
1775PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1776
1777includecheck:
1778	find $(srctree)/* $(RCS_FIND_IGNORE) \
1779		-name '*.[hcS]' -type f -print | sort \
1780		| xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1781
1782versioncheck:
1783	find $(srctree)/* $(RCS_FIND_IGNORE) \
1784		-name '*.[hcS]' -type f -print | sort \
1785		| xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1786
1787coccicheck:
1788	$(Q)$(BASH) $(srctree)/scripts/$@
1789
1790namespacecheck:
1791	$(PERL) $(srctree)/scripts/namespace.pl
1792
1793export_report:
1794	$(PERL) $(srctree)/scripts/export_report.pl
1795
1796PHONY += checkstack kernelrelease kernelversion image_name
1797
1798# UML needs a little special treatment here.  It wants to use the host
1799# toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
1800# else wants $(ARCH), including people doing cross-builds, which means
1801# that $(SUBARCH) doesn't work here.
1802ifeq ($(ARCH), um)
1803CHECKSTACK_ARCH := $(SUBARCH)
1804else
1805CHECKSTACK_ARCH := $(ARCH)
1806endif
1807checkstack:
1808	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1809	$(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1810
1811kernelrelease:
1812	@echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1813
1814kernelversion:
1815	@echo $(KERNELVERSION)
1816
1817image_name:
1818	@echo $(KBUILD_IMAGE)
1819
1820# Clear a bunch of variables before executing the submake
1821
1822ifeq ($(quiet),silent_)
1823tools_silent=s
1824endif
1825
1826tools/: FORCE
1827	$(Q)mkdir -p $(objtree)/tools
1828	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1829
1830tools/%: FORCE
1831	$(Q)mkdir -p $(objtree)/tools
1832	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1833
1834# FIXME Should go into a make.lib or something
1835# ===========================================================================
1836
1837quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN   $(wildcard $(rm-dirs)))
1838      cmd_rmdirs = rm -rf $(rm-dirs)
1839
1840quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
1841      cmd_rmfiles = rm -f $(rm-files)
1842
1843# Run depmod only if we have System.map and depmod is executable
1844quiet_cmd_depmod = DEPMOD  $(KERNELRELEASE)
1845      cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1846                   $(KERNELRELEASE)
1847
1848# read saved command lines for existing targets
1849existing-targets := $(wildcard $(sort $(targets)))
1850
1851-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
1852
1853endif # config-build
1854endif # mixed-build
1855endif # need-sub-make
1856
1857PHONY += FORCE
1858FORCE:
1859
1860# Declare the contents of the PHONY variable as phony.  We keep that
1861# information in a variable so we can use it in if_changed and friends.
1862.PHONY: $(PHONY)
1863