xref: /openbmc/linux/Makefile (revision ca5999fd)
1# SPDX-License-Identifier: GPL-2.0
2VERSION = 5
3PATCHLEVEL = 7
4SUBLEVEL = 0
5EXTRAVERSION =
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$(if $(filter __%, $(MAKECMDGOALS)), \
15	$(error targets prefixed with '__' are only for internal use))
16
17# That's our default target when none is given on the command line
18PHONY := __all
19__all:
20
21# We are using a recursive build, so we need to do a little thinking
22# to get the ordering right.
23#
24# Most importantly: sub-Makefiles should only ever modify files in
25# their own directory. If in some directory we have a dependency on
26# a file in another dir (which doesn't happen often, but it's often
27# unavoidable when linking the built-in.a targets which finally
28# turn into vmlinux), we will call a sub make in that other dir, and
29# after that we are sure that everything which is in that other dir
30# is now up to date.
31#
32# The only cases where we need to modify files which have global
33# effects are thus separated out and done before the recursive
34# descending is started. They are now explicitly listed as the
35# prepare rule.
36
37ifneq ($(sub_make_done),1)
38
39# Do not use make's built-in rules and variables
40# (this increases performance and avoids hard-to-debug behaviour)
41MAKEFLAGS += -rR
42
43# Avoid funny character set dependencies
44unexport LC_ALL
45LC_COLLATE=C
46LC_NUMERIC=C
47export LC_COLLATE LC_NUMERIC
48
49# Avoid interference with shell env settings
50unexport GREP_OPTIONS
51
52# Beautify output
53# ---------------------------------------------------------------------------
54#
55# Normally, we echo the whole command before executing it. By making
56# that echo $($(quiet)$(cmd)), we now have the possibility to set
57# $(quiet) to choose other forms of output instead, e.g.
58#
59#         quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
60#         cmd_cc_o_c       = $(CC) $(c_flags) -c -o $@ $<
61#
62# If $(quiet) is empty, the whole command will be printed.
63# If it is set to "quiet_", only the short version will be printed.
64# If it is set to "silent_", nothing will be printed at all, since
65# the variable $(silent_cmd_cc_o_c) doesn't exist.
66#
67# A simple variant is to prefix commands with $(Q) - that's useful
68# for commands that shall be hidden in non-verbose mode.
69#
70#	$(Q)ln $@ :<
71#
72# If KBUILD_VERBOSE equals 0 then the above command will be hidden.
73# If KBUILD_VERBOSE equals 1 then the above command is displayed.
74# If KBUILD_VERBOSE equals 2 then give the reason why each target is rebuilt.
75#
76# To put more focus on warnings, be less verbose as default
77# Use 'make V=1' to see the full commands
78
79ifeq ("$(origin V)", "command line")
80  KBUILD_VERBOSE = $(V)
81endif
82ifndef KBUILD_VERBOSE
83  KBUILD_VERBOSE = 0
84endif
85
86ifeq ($(KBUILD_VERBOSE),1)
87  quiet =
88  Q =
89else
90  quiet=quiet_
91  Q = @
92endif
93
94# If the user is running make -s (silent mode), suppress echoing of
95# commands
96
97ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
98  quiet=silent_
99endif
100
101export quiet Q KBUILD_VERBOSE
102
103# Kbuild will save output files in the current working directory.
104# This does not need to match to the root of the kernel source tree.
105#
106# For example, you can do this:
107#
108#  cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
109#
110# If you want to save output files in a different location, there are
111# two syntaxes to specify it.
112#
113# 1) O=
114# Use "make O=dir/to/store/output/files/"
115#
116# 2) Set KBUILD_OUTPUT
117# Set the environment variable KBUILD_OUTPUT to point to the output directory.
118# export KBUILD_OUTPUT=dir/to/store/output/files/; make
119#
120# The O= assignment takes precedence over the KBUILD_OUTPUT environment
121# variable.
122
123# Do we want to change the working directory?
124ifeq ("$(origin O)", "command line")
125  KBUILD_OUTPUT := $(O)
126endif
127
128ifneq ($(KBUILD_OUTPUT),)
129# Make's built-in functions such as $(abspath ...), $(realpath ...) cannot
130# expand a shell special character '~'. We use a somewhat tedious way here.
131abs_objtree := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) && pwd)
132$(if $(abs_objtree),, \
133     $(error failed to create output directory "$(KBUILD_OUTPUT)"))
134
135# $(realpath ...) resolves symlinks
136abs_objtree := $(realpath $(abs_objtree))
137else
138abs_objtree := $(CURDIR)
139endif # ifneq ($(KBUILD_OUTPUT),)
140
141ifeq ($(abs_objtree),$(CURDIR))
142# Suppress "Entering directory ..." unless we are changing the work directory.
143MAKEFLAGS += --no-print-directory
144else
145need-sub-make := 1
146endif
147
148abs_srctree := $(realpath $(dir $(lastword $(MAKEFILE_LIST))))
149
150ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
151$(error source directory cannot contain spaces or colons)
152endif
153
154ifneq ($(abs_srctree),$(abs_objtree))
155# Look for make include files relative to root of kernel src
156#
157# This does not become effective immediately because MAKEFLAGS is re-parsed
158# once after the Makefile is read. We need to invoke sub-make.
159MAKEFLAGS += --include-dir=$(abs_srctree)
160need-sub-make := 1
161endif
162
163this-makefile := $(lastword $(MAKEFILE_LIST))
164
165ifneq ($(filter 3.%,$(MAKE_VERSION)),)
166# 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
167# We need to invoke sub-make to avoid implicit rules in the top Makefile.
168need-sub-make := 1
169# Cancel implicit rules for this Makefile.
170$(this-makefile): ;
171endif
172
173export abs_srctree abs_objtree
174export sub_make_done := 1
175
176ifeq ($(need-sub-make),1)
177
178PHONY += $(MAKECMDGOALS) __sub-make
179
180$(filter-out $(this-makefile), $(MAKECMDGOALS)) __all: __sub-make
181	@:
182
183# Invoke a second make in the output directory, passing relevant variables
184__sub-make:
185	$(Q)$(MAKE) -C $(abs_objtree) -f $(abs_srctree)/Makefile $(MAKECMDGOALS)
186
187endif # need-sub-make
188endif # sub_make_done
189
190# We process the rest of the Makefile if this is the final invocation of make
191ifeq ($(need-sub-make),)
192
193# Do not print "Entering directory ...",
194# but we want to display it when entering to the output directory
195# so that IDEs/editors are able to understand relative filenames.
196MAKEFLAGS += --no-print-directory
197
198# Call a source code checker (by default, "sparse") as part of the
199# C compilation.
200#
201# Use 'make C=1' to enable checking of only re-compiled files.
202# Use 'make C=2' to enable checking of *all* source files, regardless
203# of whether they are re-compiled or not.
204#
205# See the file "Documentation/dev-tools/sparse.rst" for more details,
206# including where to get the "sparse" utility.
207
208ifeq ("$(origin C)", "command line")
209  KBUILD_CHECKSRC = $(C)
210endif
211ifndef KBUILD_CHECKSRC
212  KBUILD_CHECKSRC = 0
213endif
214
215# Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
216# directory of external module to build. Setting M= takes precedence.
217ifeq ("$(origin M)", "command line")
218  KBUILD_EXTMOD := $(M)
219endif
220
221$(if $(word 2, $(KBUILD_EXTMOD)), \
222	$(error building multiple external modules is not supported))
223
224export KBUILD_CHECKSRC KBUILD_EXTMOD
225
226extmod-prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
227
228ifeq ($(abs_srctree),$(abs_objtree))
229        # building in the source tree
230        srctree := .
231	building_out_of_srctree :=
232else
233        ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
234                # building in a subdirectory of the source tree
235                srctree := ..
236        else
237                srctree := $(abs_srctree)
238        endif
239	building_out_of_srctree := 1
240endif
241
242ifneq ($(KBUILD_ABS_SRCTREE),)
243srctree := $(abs_srctree)
244endif
245
246objtree		:= .
247VPATH		:= $(srctree)
248
249export building_out_of_srctree srctree objtree VPATH
250
251# To make sure we do not include .config for any of the *config targets
252# catch them early, and hand them over to scripts/kconfig/Makefile
253# It is allowed to specify more targets when calling make, including
254# mixing *config targets and build targets.
255# For example 'make oldconfig all'.
256# Detect when mixed targets is specified, and make a second invocation
257# of make so .config is not included in this case either (for *config).
258
259version_h := include/generated/uapi/linux/version.h
260old_version_h := include/linux/version.h
261
262clean-targets := %clean mrproper cleandocs
263no-dot-config-targets := $(clean-targets) \
264			 cscope gtags TAGS tags help% %docs check% coccicheck \
265			 $(version_h) headers headers_% archheaders archscripts \
266			 %asm-generic kernelversion %src-pkg dt_binding_check \
267			 outputmakefile
268no-sync-config-targets := $(no-dot-config-targets) install %install \
269			   kernelrelease
270single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
271
272config-build	:=
273mixed-build	:=
274need-config	:= 1
275may-sync-config	:= 1
276single-build	:=
277
278ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
279	ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
280		need-config :=
281	endif
282endif
283
284ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
285	ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
286		may-sync-config :=
287	endif
288endif
289
290ifneq ($(KBUILD_EXTMOD),)
291	may-sync-config :=
292endif
293
294ifeq ($(KBUILD_EXTMOD),)
295        ifneq ($(filter config %config,$(MAKECMDGOALS)),)
296		config-build := 1
297                ifneq ($(words $(MAKECMDGOALS)),1)
298			mixed-build := 1
299                endif
300        endif
301endif
302
303# We cannot build single targets and the others at the same time
304ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
305	single-build := 1
306	ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
307		mixed-build := 1
308	endif
309endif
310
311# For "make -j clean all", "make -j mrproper defconfig all", etc.
312ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
313        ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
314		mixed-build := 1
315        endif
316endif
317
318# install and modules_install need also be processed one by one
319ifneq ($(filter install,$(MAKECMDGOALS)),)
320        ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
321		mixed-build := 1
322        endif
323endif
324
325ifdef mixed-build
326# ===========================================================================
327# We're called with mixed targets (*config and build targets).
328# Handle them one by one.
329
330PHONY += $(MAKECMDGOALS) __build_one_by_one
331
332$(MAKECMDGOALS): __build_one_by_one
333	@:
334
335__build_one_by_one:
336	$(Q)set -e; \
337	for i in $(MAKECMDGOALS); do \
338		$(MAKE) -f $(srctree)/Makefile $$i; \
339	done
340
341else # !mixed-build
342
343include scripts/Kbuild.include
344
345# Read KERNELRELEASE from include/config/kernel.release (if it exists)
346KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
347KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
348export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
349
350include scripts/subarch.include
351
352# Cross compiling and selecting different set of gcc/bin-utils
353# ---------------------------------------------------------------------------
354#
355# When performing cross compilation for other architectures ARCH shall be set
356# to the target architecture. (See arch/* for the possibilities).
357# ARCH can be set during invocation of make:
358# make ARCH=ia64
359# Another way is to have ARCH set in the environment.
360# The default ARCH is the host where make is executed.
361
362# CROSS_COMPILE specify the prefix used for all executables used
363# during compilation. Only gcc and related bin-utils executables
364# are prefixed with $(CROSS_COMPILE).
365# CROSS_COMPILE can be set on the command line
366# make CROSS_COMPILE=ia64-linux-
367# Alternatively CROSS_COMPILE can be set in the environment.
368# Default value for CROSS_COMPILE is not to prefix executables
369# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
370ARCH		?= $(SUBARCH)
371
372# Architecture as present in compile.h
373UTS_MACHINE 	:= $(ARCH)
374SRCARCH 	:= $(ARCH)
375
376# Additional ARCH settings for x86
377ifeq ($(ARCH),i386)
378        SRCARCH := x86
379endif
380ifeq ($(ARCH),x86_64)
381        SRCARCH := x86
382endif
383
384# Additional ARCH settings for sparc
385ifeq ($(ARCH),sparc32)
386       SRCARCH := sparc
387endif
388ifeq ($(ARCH),sparc64)
389       SRCARCH := sparc
390endif
391
392# Additional ARCH settings for sh
393ifeq ($(ARCH),sh64)
394       SRCARCH := sh
395endif
396
397KCONFIG_CONFIG	?= .config
398export KCONFIG_CONFIG
399
400# Default file for 'make defconfig'. This may be overridden by arch-Makefile.
401export KBUILD_DEFCONFIG := defconfig
402
403# SHELL used by kbuild
404CONFIG_SHELL := sh
405
406HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
407HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
408HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
409
410ifneq ($(LLVM),)
411HOSTCC	= clang
412HOSTCXX	= clang++
413else
414HOSTCC	= gcc
415HOSTCXX	= g++
416endif
417
418export KBUILD_USERCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
419			      -O2 -fomit-frame-pointer -std=gnu89
420export KBUILD_USERLDFLAGS :=
421
422KBUILD_HOSTCFLAGS   := $(KBUILD_USERCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
423KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
424KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
425KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
426
427# Make variables (CC, etc...)
428CPP		= $(CC) -E
429ifneq ($(LLVM),)
430CC		= clang
431LD		= ld.lld
432AR		= llvm-ar
433NM		= llvm-nm
434OBJCOPY		= llvm-objcopy
435OBJDUMP		= llvm-objdump
436READELF		= llvm-readelf
437OBJSIZE		= llvm-size
438STRIP		= llvm-strip
439else
440CC		= $(CROSS_COMPILE)gcc
441LD		= $(CROSS_COMPILE)ld
442AR		= $(CROSS_COMPILE)ar
443NM		= $(CROSS_COMPILE)nm
444OBJCOPY		= $(CROSS_COMPILE)objcopy
445OBJDUMP		= $(CROSS_COMPILE)objdump
446READELF		= $(CROSS_COMPILE)readelf
447OBJSIZE		= $(CROSS_COMPILE)size
448STRIP		= $(CROSS_COMPILE)strip
449endif
450PAHOLE		= pahole
451LEX		= flex
452YACC		= bison
453AWK		= awk
454INSTALLKERNEL  := installkernel
455DEPMOD		= /sbin/depmod
456PERL		= perl
457PYTHON		= python
458PYTHON3		= python3
459CHECK		= sparse
460BASH		= bash
461GZIP		= gzip
462BZIP2		= bzip2
463LZOP		= lzop
464LZMA		= lzma
465LZ4		= lz4c
466XZ		= xz
467
468# GZIP, BZIP2, LZOP env vars are used by the tools. Support them as the command
469# line interface, but use _GZIP, _BZIP2, _LZOP internally.
470_GZIP          := $(GZIP)
471_BZIP2         := $(BZIP2)
472_LZOP          := $(LZOP)
473
474# Reset GZIP, BZIP2, LZOP in this Makefile
475override GZIP=
476override BZIP2=
477override LZOP=
478
479# Reset GZIP, BZIP2, LZOP in recursive invocations
480MAKEOVERRIDES += GZIP= BZIP2= LZOP=
481
482CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
483		  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
484NOSTDINC_FLAGS :=
485CFLAGS_MODULE   =
486AFLAGS_MODULE   =
487LDFLAGS_MODULE  =
488CFLAGS_KERNEL	=
489AFLAGS_KERNEL	=
490LDFLAGS_vmlinux =
491
492# Use USERINCLUDE when you must reference the UAPI directories only.
493USERINCLUDE    := \
494		-I$(srctree)/arch/$(SRCARCH)/include/uapi \
495		-I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
496		-I$(srctree)/include/uapi \
497		-I$(objtree)/include/generated/uapi \
498                -include $(srctree)/include/linux/kconfig.h
499
500# Use LINUXINCLUDE when you must reference the include/ directory.
501# Needed to be compatible with the O= option
502LINUXINCLUDE    := \
503		-I$(srctree)/arch/$(SRCARCH)/include \
504		-I$(objtree)/arch/$(SRCARCH)/include/generated \
505		$(if $(building_out_of_srctree),-I$(srctree)/include) \
506		-I$(objtree)/include \
507		$(USERINCLUDE)
508
509KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
510KBUILD_CFLAGS   := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
511		   -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
512		   -Werror=implicit-function-declaration -Werror=implicit-int \
513		   -Wno-format-security \
514		   -std=gnu89
515KBUILD_CPPFLAGS := -D__KERNEL__
516KBUILD_AFLAGS_KERNEL :=
517KBUILD_CFLAGS_KERNEL :=
518KBUILD_AFLAGS_MODULE  := -DMODULE
519KBUILD_CFLAGS_MODULE  := -DMODULE
520KBUILD_LDFLAGS_MODULE :=
521export KBUILD_LDS_MODULE := $(srctree)/scripts/module-common.lds
522KBUILD_LDFLAGS :=
523GCC_PLUGINS_CFLAGS :=
524CLANG_FLAGS :=
525
526export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC
527export CPP AR NM STRIP OBJCOPY OBJDUMP OBJSIZE READELF PAHOLE LEX YACC AWK INSTALLKERNEL
528export PERL PYTHON PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
529export _GZIP _BZIP2 _LZOP LZMA LZ4 XZ
530export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
531
532export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
533export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
534export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN
535export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
536export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
537export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
538
539# Files to ignore in find ... statements
540
541export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
542			  -name CVS -o -name .pc -o -name .hg -o -name .git \) \
543			  -prune -o
544export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
545			 --exclude CVS --exclude .pc --exclude .hg --exclude .git
546
547# ===========================================================================
548# Rules shared between *config targets and build targets
549
550# Basic helpers built in scripts/basic/
551PHONY += scripts_basic
552scripts_basic:
553	$(Q)$(MAKE) $(build)=scripts/basic
554	$(Q)rm -f .tmp_quiet_recordmcount
555
556PHONY += outputmakefile
557# Before starting out-of-tree build, make sure the source tree is clean.
558# outputmakefile generates a Makefile in the output directory, if using a
559# separate output directory. This allows convenient use of make in the
560# output directory.
561# At the same time when output Makefile generated, generate .gitignore to
562# ignore whole output directory
563outputmakefile:
564ifdef building_out_of_srctree
565	$(Q)if [ -f $(srctree)/.config -o \
566		 -d $(srctree)/include/config -o \
567		 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
568		echo >&2 "***"; \
569		echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
570		echo >&2 "*** in $(abs_srctree)";\
571		echo >&2 "***"; \
572		false; \
573	fi
574	$(Q)ln -fsn $(srctree) source
575	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile $(srctree)
576	$(Q)test -e .gitignore || \
577	{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
578endif
579
580ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),)
581ifneq ($(CROSS_COMPILE),)
582CLANG_FLAGS	+= --target=$(notdir $(CROSS_COMPILE:%-=%))
583GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
584CLANG_FLAGS	+= --prefix=$(GCC_TOOLCHAIN_DIR)
585GCC_TOOLCHAIN	:= $(realpath $(GCC_TOOLCHAIN_DIR)/..)
586endif
587ifneq ($(GCC_TOOLCHAIN),)
588CLANG_FLAGS	+= --gcc-toolchain=$(GCC_TOOLCHAIN)
589endif
590ifneq ($(LLVM_IAS),1)
591CLANG_FLAGS	+= -no-integrated-as
592endif
593CLANG_FLAGS	+= -Werror=unknown-warning-option
594KBUILD_CFLAGS	+= $(CLANG_FLAGS)
595KBUILD_AFLAGS	+= $(CLANG_FLAGS)
596export CLANG_FLAGS
597endif
598
599# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
600# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
601# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
602# and from include/config/auto.conf.cmd to detect the compiler upgrade.
603CC_VERSION_TEXT = $(shell $(CC) --version 2>/dev/null | head -n 1)
604
605ifdef config-build
606# ===========================================================================
607# *config targets only - make sure prerequisites are updated, and descend
608# in scripts/kconfig to make the *config target
609
610# Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
611# KBUILD_DEFCONFIG may point out an alternative default configuration
612# used for 'make defconfig'
613include arch/$(SRCARCH)/Makefile
614export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
615
616config: outputmakefile scripts_basic FORCE
617	$(Q)$(MAKE) $(build)=scripts/kconfig $@
618
619%config: outputmakefile scripts_basic FORCE
620	$(Q)$(MAKE) $(build)=scripts/kconfig $@
621
622else #!config-build
623# ===========================================================================
624# Build targets only - this includes vmlinux, arch specific targets, clean
625# targets and others. In general all targets except *config targets.
626
627# If building an external module we do not care about the all: rule
628# but instead __all depend on modules
629PHONY += all
630ifeq ($(KBUILD_EXTMOD),)
631__all: all
632else
633__all: modules
634endif
635
636# Decide whether to build built-in, modular, or both.
637# Normally, just do built-in.
638
639KBUILD_MODULES :=
640KBUILD_BUILTIN := 1
641
642# If we have only "make modules", don't compile built-in objects.
643ifeq ($(MAKECMDGOALS),modules)
644  KBUILD_BUILTIN :=
645endif
646
647# If we have "make <whatever> modules", compile modules
648# in addition to whatever we do anyway.
649# Just "make" or "make all" shall build modules as well
650
651ifneq ($(filter all modules nsdeps,$(MAKECMDGOALS)),)
652  KBUILD_MODULES := 1
653endif
654
655ifeq ($(MAKECMDGOALS),)
656  KBUILD_MODULES := 1
657endif
658
659export KBUILD_MODULES KBUILD_BUILTIN
660
661ifdef need-config
662include include/config/auto.conf
663endif
664
665ifeq ($(KBUILD_EXTMOD),)
666# Objects we will link into vmlinux / subdirs we need to visit
667core-y		:= init/ usr/
668drivers-y	:= drivers/ sound/
669drivers-$(CONFIG_SAMPLES) += samples/
670drivers-y	+= net/ virt/
671libs-y		:= lib/
672endif # KBUILD_EXTMOD
673
674# The all: target is the default when no target is given on the
675# command line.
676# This allow a user to issue only 'make' to build a kernel including modules
677# Defaults to vmlinux, but the arch makefile usually adds further targets
678all: vmlinux
679
680CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage \
681	$(call cc-option,-fno-tree-loop-im) \
682	$(call cc-disable-warning,maybe-uninitialized,)
683export CFLAGS_GCOV
684
685# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
686ifdef CONFIG_FUNCTION_TRACER
687  CC_FLAGS_FTRACE := -pg
688endif
689
690RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
691RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
692RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
693RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
694RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
695RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
696export RETPOLINE_CFLAGS
697export RETPOLINE_VDSO_CFLAGS
698
699include arch/$(SRCARCH)/Makefile
700
701ifdef need-config
702ifdef may-sync-config
703# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
704# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
705# because some architectures define CROSS_COMPILE there.
706include include/config/auto.conf.cmd
707
708$(KCONFIG_CONFIG):
709	@echo >&2 '***'
710	@echo >&2 '*** Configuration file "$@" not found!'
711	@echo >&2 '***'
712	@echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
713	@echo >&2 '*** "make menuconfig" or "make xconfig").'
714	@echo >&2 '***'
715	@/bin/false
716
717# The actual configuration files used during the build are stored in
718# include/generated/ and include/config/. Update them if .config is newer than
719# include/config/auto.conf (which mirrors .config).
720#
721# This exploits the 'multi-target pattern rule' trick.
722# The syncconfig should be executed only once to make all the targets.
723# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
724%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h: $(KCONFIG_CONFIG)
725	$(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
726else # !may-sync-config
727# External modules and some install targets need include/generated/autoconf.h
728# and include/config/auto.conf but do not care if they are up-to-date.
729# Use auto.conf to trigger the test
730PHONY += include/config/auto.conf
731
732include/config/auto.conf:
733	$(Q)test -e include/generated/autoconf.h -a -e $@ || (		\
734	echo >&2;							\
735	echo >&2 "  ERROR: Kernel configuration is invalid.";		\
736	echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
737	echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";	\
738	echo >&2 ;							\
739	/bin/false)
740
741endif # may-sync-config
742endif # need-config
743
744KBUILD_CFLAGS	+= $(call cc-option,-fno-delete-null-pointer-checks,)
745KBUILD_CFLAGS	+= $(call cc-disable-warning,frame-address,)
746KBUILD_CFLAGS	+= $(call cc-disable-warning, format-truncation)
747KBUILD_CFLAGS	+= $(call cc-disable-warning, format-overflow)
748KBUILD_CFLAGS	+= $(call cc-disable-warning, address-of-packed-member)
749
750ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
751KBUILD_CFLAGS += -O2
752else ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3
753KBUILD_CFLAGS += -O3
754else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
755KBUILD_CFLAGS += -Os
756endif
757
758# Tell gcc to never replace conditional load with a non-conditional one
759KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
760KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
761
762include scripts/Makefile.kcov
763include scripts/Makefile.gcc-plugins
764
765ifdef CONFIG_READABLE_ASM
766# Disable optimizations that make assembler listings hard to read.
767# reorder blocks reorders the control in the function
768# ipa clone creates specialized cloned functions
769# partial inlining inlines only parts of functions
770KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
771                 $(call cc-option,-fno-ipa-cp-clone,) \
772                 $(call cc-option,-fno-partial-inlining)
773endif
774
775ifneq ($(CONFIG_FRAME_WARN),0)
776KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
777endif
778
779stackp-flags-$(CONFIG_CC_HAS_STACKPROTECTOR_NONE) := -fno-stack-protector
780stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
781stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
782
783KBUILD_CFLAGS += $(stackp-flags-y)
784
785ifdef CONFIG_CC_IS_CLANG
786KBUILD_CPPFLAGS += -Qunused-arguments
787KBUILD_CFLAGS += -Wno-format-invalid-specifier
788KBUILD_CFLAGS += -Wno-gnu
789# CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
790# source of a reference will be _MergedGlobals and not on of the whitelisted names.
791# See modpost pattern 2
792KBUILD_CFLAGS += -mno-global-merge
793else
794
795# These warnings generated too much noise in a regular build.
796# Use make W=1 to enable them (see scripts/Makefile.extrawarn)
797KBUILD_CFLAGS += -Wno-unused-but-set-variable
798
799# Warn about unmarked fall-throughs in switch statement.
800# Disabled for clang while comment to attribute conversion happens and
801# https://github.com/ClangBuiltLinux/linux/issues/636 is discussed.
802KBUILD_CFLAGS += $(call cc-option,-Wimplicit-fallthrough,)
803endif
804
805KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
806ifdef CONFIG_FRAME_POINTER
807KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
808else
809# Some targets (ARM with Thumb2, for example), can't be built with frame
810# pointers.  For those, we don't have FUNCTION_TRACER automatically
811# select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
812# incompatible with -fomit-frame-pointer with current GCC, so we don't use
813# -fomit-frame-pointer with FUNCTION_TRACER.
814ifndef CONFIG_FUNCTION_TRACER
815KBUILD_CFLAGS	+= -fomit-frame-pointer
816endif
817endif
818
819# Initialize all stack variables with a pattern, if desired.
820ifdef CONFIG_INIT_STACK_ALL
821KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
822endif
823
824DEBUG_CFLAGS	:= $(call cc-option, -fno-var-tracking-assignments)
825
826ifdef CONFIG_DEBUG_INFO
827ifdef CONFIG_DEBUG_INFO_SPLIT
828DEBUG_CFLAGS	+= -gsplit-dwarf
829else
830DEBUG_CFLAGS	+= -g
831endif
832KBUILD_AFLAGS	+= -Wa,-gdwarf-2
833endif
834ifdef CONFIG_DEBUG_INFO_DWARF4
835DEBUG_CFLAGS	+= -gdwarf-4
836endif
837
838ifdef CONFIG_DEBUG_INFO_REDUCED
839DEBUG_CFLAGS	+= $(call cc-option, -femit-struct-debug-baseonly) \
840		   $(call cc-option,-fno-var-tracking)
841endif
842
843ifdef CONFIG_DEBUG_INFO_COMPRESSED
844DEBUG_CFLAGS	+= -gz=zlib
845KBUILD_AFLAGS	+= -Wa,--compress-debug-sections=zlib
846KBUILD_LDFLAGS	+= --compress-debug-sections=zlib
847endif
848
849KBUILD_CFLAGS += $(DEBUG_CFLAGS)
850export DEBUG_CFLAGS
851
852ifdef CONFIG_FUNCTION_TRACER
853ifdef CONFIG_FTRACE_MCOUNT_RECORD
854  # gcc 5 supports generating the mcount tables directly
855  ifeq ($(call cc-option-yn,-mrecord-mcount),y)
856    CC_FLAGS_FTRACE	+= -mrecord-mcount
857    export CC_USING_RECORD_MCOUNT := 1
858  endif
859  ifdef CONFIG_HAVE_NOP_MCOUNT
860    ifeq ($(call cc-option-yn, -mnop-mcount),y)
861      CC_FLAGS_FTRACE	+= -mnop-mcount
862      CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
863    endif
864  endif
865endif
866ifdef CONFIG_HAVE_FENTRY
867  ifeq ($(call cc-option-yn, -mfentry),y)
868    CC_FLAGS_FTRACE	+= -mfentry
869    CC_FLAGS_USING	+= -DCC_USING_FENTRY
870  endif
871endif
872export CC_FLAGS_FTRACE
873KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
874KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
875ifdef CONFIG_DYNAMIC_FTRACE
876	ifdef CONFIG_HAVE_C_RECORDMCOUNT
877		BUILD_C_RECORDMCOUNT := y
878		export BUILD_C_RECORDMCOUNT
879	endif
880endif
881endif
882
883# We trigger additional mismatches with less inlining
884ifdef CONFIG_DEBUG_SECTION_MISMATCH
885KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
886endif
887
888ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
889KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
890LDFLAGS_vmlinux += --gc-sections
891endif
892
893ifdef CONFIG_LIVEPATCH
894KBUILD_CFLAGS += $(call cc-option, -flive-patching=inline-clone)
895endif
896
897ifdef CONFIG_SHADOW_CALL_STACK
898CC_FLAGS_SCS	:= -fsanitize=shadow-call-stack
899KBUILD_CFLAGS	+= $(CC_FLAGS_SCS)
900export CC_FLAGS_SCS
901endif
902
903# arch Makefile may override CC so keep this after arch Makefile is included
904NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
905
906# warn about C99 declaration after statement
907KBUILD_CFLAGS += -Wdeclaration-after-statement
908
909# Variable Length Arrays (VLAs) should not be used anywhere in the kernel
910KBUILD_CFLAGS += -Wvla
911
912# disable pointer signed / unsigned warnings in gcc 4.0
913KBUILD_CFLAGS += -Wno-pointer-sign
914
915# disable stringop warnings in gcc 8+
916KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
917
918# We'll want to enable this eventually, but it's not going away for 5.7 at least
919KBUILD_CFLAGS += $(call cc-disable-warning, zero-length-bounds)
920KBUILD_CFLAGS += $(call cc-disable-warning, array-bounds)
921KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
922
923# Another good warning that we'll want to enable eventually
924KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
925
926# Enabled with W=2, disabled by default as noisy
927KBUILD_CFLAGS += $(call cc-disable-warning, maybe-uninitialized)
928
929# disable invalid "can't wrap" optimizations for signed / pointers
930KBUILD_CFLAGS	+= $(call cc-option,-fno-strict-overflow)
931
932# clang sets -fmerge-all-constants by default as optimization, but this
933# is non-conforming behavior for C and in fact breaks the kernel, so we
934# need to disable it here generally.
935KBUILD_CFLAGS	+= $(call cc-option,-fno-merge-all-constants)
936
937# for gcc -fno-merge-all-constants disables everything, but it is fine
938# to have actual conforming behavior enabled.
939KBUILD_CFLAGS	+= $(call cc-option,-fmerge-constants)
940
941# Make sure -fstack-check isn't enabled (like gentoo apparently did)
942KBUILD_CFLAGS  += $(call cc-option,-fno-stack-check,)
943
944# conserve stack if available
945KBUILD_CFLAGS   += $(call cc-option,-fconserve-stack)
946
947# Prohibit date/time macros, which would make the build non-deterministic
948KBUILD_CFLAGS   += $(call cc-option,-Werror=date-time)
949
950# enforce correct pointer usage
951KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)
952
953# Require designated initializers for all marked structures
954KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)
955
956# change __FILE__ to the relative path from the srctree
957KBUILD_CFLAGS	+= $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
958
959# ensure -fcf-protection is disabled when using retpoline as it is
960# incompatible with -mindirect-branch=thunk-extern
961ifdef CONFIG_RETPOLINE
962KBUILD_CFLAGS += $(call cc-option,-fcf-protection=none)
963endif
964
965include scripts/Makefile.kasan
966include scripts/Makefile.extrawarn
967include scripts/Makefile.ubsan
968
969# Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
970KBUILD_CPPFLAGS += $(KCPPFLAGS)
971KBUILD_AFLAGS   += $(KAFLAGS)
972KBUILD_CFLAGS   += $(KCFLAGS)
973
974KBUILD_LDFLAGS_MODULE += --build-id
975LDFLAGS_vmlinux += --build-id
976
977ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
978LDFLAGS_vmlinux	+= $(call ld-option, -X,)
979endif
980
981ifeq ($(CONFIG_RELR),y)
982LDFLAGS_vmlinux	+= --pack-dyn-relocs=relr
983endif
984
985# Align the bit size of userspace programs with the kernel
986KBUILD_USERCFLAGS  += $(filter -m32 -m64, $(KBUILD_CFLAGS))
987KBUILD_USERLDFLAGS += $(filter -m32 -m64, $(KBUILD_CFLAGS))
988
989# make the checker run with the right architecture
990CHECKFLAGS += --arch=$(ARCH)
991
992# insure the checker run with the right endianness
993CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
994
995# the checker needs the correct machine size
996CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
997
998# Default kernel image to build when no specific target is given.
999# KBUILD_IMAGE may be overruled on the command line or
1000# set in the environment
1001# Also any assignments in arch/$(ARCH)/Makefile take precedence over
1002# this default value
1003export KBUILD_IMAGE ?= vmlinux
1004
1005#
1006# INSTALL_PATH specifies where to place the updated kernel and system map
1007# images. Default is /boot, but you can set it to other values
1008export	INSTALL_PATH ?= /boot
1009
1010#
1011# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1012# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1013# an argument if needed. Otherwise it defaults to the kernel install path
1014#
1015export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1016
1017#
1018# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1019# relocations required by build roots.  This is not defined in the
1020# makefile but the argument can be passed to make if needed.
1021#
1022
1023MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1024export MODLIB
1025
1026#
1027# INSTALL_MOD_STRIP, if defined, will cause modules to be
1028# stripped after they are installed.  If INSTALL_MOD_STRIP is '1', then
1029# the default option --strip-debug will be used.  Otherwise,
1030# INSTALL_MOD_STRIP value will be used as the options to the strip command.
1031
1032ifdef INSTALL_MOD_STRIP
1033ifeq ($(INSTALL_MOD_STRIP),1)
1034mod_strip_cmd = $(STRIP) --strip-debug
1035else
1036mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
1037endif # INSTALL_MOD_STRIP=1
1038else
1039mod_strip_cmd = true
1040endif # INSTALL_MOD_STRIP
1041export mod_strip_cmd
1042
1043# CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
1044# after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
1045# or CONFIG_MODULE_COMPRESS_XZ.
1046
1047mod_compress_cmd = true
1048ifdef CONFIG_MODULE_COMPRESS
1049  ifdef CONFIG_MODULE_COMPRESS_GZIP
1050    mod_compress_cmd = $(_GZIP) -n -f
1051  endif # CONFIG_MODULE_COMPRESS_GZIP
1052  ifdef CONFIG_MODULE_COMPRESS_XZ
1053    mod_compress_cmd = $(XZ) -f
1054  endif # CONFIG_MODULE_COMPRESS_XZ
1055endif # CONFIG_MODULE_COMPRESS
1056export mod_compress_cmd
1057
1058ifdef CONFIG_MODULE_SIG_ALL
1059$(eval $(call config_filename,MODULE_SIG_KEY))
1060
1061mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
1062else
1063mod_sign_cmd = true
1064endif
1065export mod_sign_cmd
1066
1067HOST_LIBELF_LIBS = $(shell pkg-config libelf --libs 2>/dev/null || echo -lelf)
1068
1069ifdef CONFIG_STACK_VALIDATION
1070  has_libelf := $(call try-run,\
1071		echo "int main() {}" | $(HOSTCC) -xc -o /dev/null $(HOST_LIBELF_LIBS) -,1,0)
1072  ifeq ($(has_libelf),1)
1073    objtool_target := tools/objtool FORCE
1074  else
1075    SKIP_STACK_VALIDATION := 1
1076    export SKIP_STACK_VALIDATION
1077  endif
1078endif
1079
1080PHONY += prepare0
1081
1082export MODORDER := $(extmod-prefix)modules.order
1083export MODULES_NSDEPS := $(extmod-prefix)modules.nsdeps
1084
1085ifeq ($(KBUILD_EXTMOD),)
1086core-y		+= kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
1087
1088vmlinux-dirs	:= $(patsubst %/,%,$(filter %/, \
1089		     $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
1090		     $(libs-y) $(libs-m)))
1091
1092vmlinux-alldirs	:= $(sort $(vmlinux-dirs) Documentation \
1093		     $(patsubst %/,%,$(filter %/, $(core-) \
1094			$(drivers-) $(libs-))))
1095
1096subdir-modorder := $(addsuffix modules.order,$(filter %/, \
1097			$(core-y) $(core-m) $(libs-y) $(libs-m) \
1098			$(drivers-y) $(drivers-m)))
1099
1100build-dirs	:= $(vmlinux-dirs)
1101clean-dirs	:= $(vmlinux-alldirs)
1102
1103# Externally visible symbols (used by link-vmlinux.sh)
1104KBUILD_VMLINUX_OBJS := $(head-y) $(patsubst %/,%/built-in.a, $(core-y))
1105KBUILD_VMLINUX_OBJS += $(addsuffix built-in.a, $(filter %/, $(libs-y)))
1106ifdef CONFIG_MODULES
1107KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1108KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1109else
1110KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1111endif
1112KBUILD_VMLINUX_OBJS += $(patsubst %/,%/built-in.a, $(drivers-y))
1113
1114export KBUILD_VMLINUX_OBJS KBUILD_VMLINUX_LIBS
1115export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1116export LDFLAGS_vmlinux
1117# used by scripts/Makefile.package
1118export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) LICENSES arch include scripts tools)
1119
1120vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
1121
1122# Recurse until adjust_autoksyms.sh is satisfied
1123PHONY += autoksyms_recursive
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.
1127# (this can be evaluated only once include/config/auto.conf has been included)
1128KBUILD_MODULES := 1
1129
1130autoksyms_recursive: descend modules.order
1131	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1132	  "$(MAKE) -f $(srctree)/Makefile vmlinux"
1133endif
1134
1135autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1136
1137quiet_cmd_autoksyms_h = GEN     $@
1138      cmd_autoksyms_h = mkdir -p $(dir $@); \
1139			$(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@
1140
1141$(autoksyms_h):
1142	$(call cmd,autoksyms_h)
1143
1144ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1145
1146# Final link of vmlinux with optional arch pass after final link
1147cmd_link-vmlinux =                                                 \
1148	$(CONFIG_SHELL) $< $(LD) $(KBUILD_LDFLAGS) $(LDFLAGS_vmlinux) ;    \
1149	$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1150
1151vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1152	+$(call if_changed,link-vmlinux)
1153
1154targets := vmlinux
1155
1156# The actual objects are generated when descending,
1157# make sure no implicit rule kicks in
1158$(sort $(vmlinux-deps) $(subdir-modorder)): descend ;
1159
1160filechk_kernel.release = \
1161	echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1162
1163# Store (new) KERNELRELEASE string in include/config/kernel.release
1164include/config/kernel.release: FORCE
1165	$(call filechk,kernel.release)
1166
1167# Additional helpers built in scripts/
1168# Carefully list dependencies so we do not try to build scripts twice
1169# in parallel
1170PHONY += scripts
1171scripts: scripts_basic scripts_dtc
1172	$(Q)$(MAKE) $(build)=$(@)
1173
1174# Things we need to do before we recursively start building the kernel
1175# or the modules are listed in "prepare".
1176# A multi level approach is used. prepareN is processed before prepareN-1.
1177# archprepare is used in arch Makefiles and when processed asm symlink,
1178# version.h and scripts_basic is processed / created.
1179
1180PHONY += prepare archprepare
1181
1182archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1183	asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h \
1184	include/generated/autoconf.h
1185
1186prepare0: archprepare
1187	$(Q)$(MAKE) $(build)=scripts/mod
1188	$(Q)$(MAKE) $(build)=.
1189
1190# All the preparing..
1191prepare: prepare0 prepare-objtool
1192
1193# Support for using generic headers in asm-generic
1194asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1195
1196PHONY += asm-generic uapi-asm-generic
1197asm-generic: uapi-asm-generic
1198	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1199	generic=include/asm-generic
1200uapi-asm-generic:
1201	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1202	generic=include/uapi/asm-generic
1203
1204PHONY += prepare-objtool
1205prepare-objtool: $(objtool_target)
1206ifeq ($(SKIP_STACK_VALIDATION),1)
1207ifdef CONFIG_UNWINDER_ORC
1208	@echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1209	@false
1210else
1211	@echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1212endif
1213endif
1214
1215# Generate some files
1216# ---------------------------------------------------------------------------
1217
1218# KERNELRELEASE can change from a few different places, meaning version.h
1219# needs to be updated, so this check is forced on all builds
1220
1221uts_len := 64
1222define filechk_utsrelease.h
1223	if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1224	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1225	  exit 1;                                                         \
1226	fi;                                                               \
1227	echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1228endef
1229
1230define filechk_version.h
1231	echo \#define LINUX_VERSION_CODE $(shell                         \
1232	expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1233	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))'
1234endef
1235
1236$(version_h): FORCE
1237	$(call filechk,version.h)
1238	$(Q)rm -f $(old_version_h)
1239
1240include/generated/utsrelease.h: include/config/kernel.release FORCE
1241	$(call filechk,utsrelease.h)
1242
1243PHONY += headerdep
1244headerdep:
1245	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1246	$(srctree)/scripts/headerdep.pl -I$(srctree)/include
1247
1248# ---------------------------------------------------------------------------
1249# Kernel headers
1250
1251#Default location for installed headers
1252export INSTALL_HDR_PATH = $(objtree)/usr
1253
1254quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1255      cmd_headers_install = \
1256	mkdir -p $(INSTALL_HDR_PATH); \
1257	rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1258	usr/include $(INSTALL_HDR_PATH)
1259
1260PHONY += headers_install
1261headers_install: headers
1262	$(call cmd,headers_install)
1263
1264PHONY += archheaders archscripts
1265
1266hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1267
1268PHONY += headers
1269headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1270	$(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1271	  $(error Headers not exportable for the $(SRCARCH) architecture))
1272	$(Q)$(MAKE) $(hdr-inst)=include/uapi
1273	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1274
1275# Deprecated. It is no-op now.
1276PHONY += headers_check
1277headers_check:
1278	@:
1279
1280ifdef CONFIG_HEADERS_INSTALL
1281prepare: headers
1282endif
1283
1284PHONY += scripts_unifdef
1285scripts_unifdef: scripts_basic
1286	$(Q)$(MAKE) $(build)=scripts scripts/unifdef
1287
1288# ---------------------------------------------------------------------------
1289# Kernel selftest
1290
1291PHONY += kselftest
1292kselftest:
1293	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1294
1295kselftest-%: FORCE
1296	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1297
1298PHONY += kselftest-merge
1299kselftest-merge:
1300	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1301	$(Q)find $(srctree)/tools/testing/selftests -name config | \
1302		xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1303	$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1304
1305# ---------------------------------------------------------------------------
1306# Devicetree files
1307
1308ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1309dtstree := arch/$(SRCARCH)/boot/dts
1310endif
1311
1312ifneq ($(dtstree),)
1313
1314%.dtb: include/config/kernel.release scripts_dtc
1315	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1316
1317PHONY += dtbs dtbs_install dtbs_check
1318dtbs: include/config/kernel.release scripts_dtc
1319	$(Q)$(MAKE) $(build)=$(dtstree)
1320
1321ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1322export CHECK_DTBS=y
1323dtbs: dt_binding_check
1324endif
1325
1326dtbs_check: dtbs
1327
1328dtbs_install:
1329	$(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1330
1331ifdef CONFIG_OF_EARLY_FLATTREE
1332all: dtbs
1333endif
1334
1335endif
1336
1337PHONY += scripts_dtc
1338scripts_dtc: scripts_basic
1339	$(Q)$(MAKE) $(build)=scripts/dtc
1340
1341ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1342export CHECK_DT_BINDING=y
1343endif
1344
1345PHONY += dt_binding_check
1346dt_binding_check: scripts_dtc
1347	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1348
1349# ---------------------------------------------------------------------------
1350# Modules
1351
1352# install modules.builtin regardless of CONFIG_MODULES
1353PHONY += _builtin_inst_
1354_builtin_inst_:
1355	@mkdir -p $(MODLIB)/
1356	@cp -f modules.builtin $(MODLIB)/
1357	@cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
1358
1359PHONY += install
1360install: _builtin_inst_
1361
1362ifdef CONFIG_MODULES
1363
1364# By default, build modules as well
1365
1366all: modules
1367
1368# When we're building modules with modversions, we need to consider
1369# the built-in objects during the descend as well, in order to
1370# make sure the checksums are up to date before we record them.
1371ifdef CONFIG_MODVERSIONS
1372  KBUILD_BUILTIN := 1
1373endif
1374
1375# Build modules
1376#
1377# A module can be listed more than once in obj-m resulting in
1378# duplicate lines in modules.order files.  Those are removed
1379# using awk while concatenating to the final file.
1380
1381PHONY += modules
1382modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_check
1383	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1384
1385PHONY += modules_check
1386modules_check: modules.order
1387	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1388
1389cmd_modules_order = $(AWK) '!x[$$0]++' $(real-prereqs) > $@
1390
1391modules.order: $(subdir-modorder) FORCE
1392	$(call if_changed,modules_order)
1393
1394targets += modules.order
1395
1396# Target to prepare building external modules
1397PHONY += modules_prepare
1398modules_prepare: prepare
1399
1400# Target to install modules
1401PHONY += modules_install
1402modules_install: _modinst_ _modinst_post
1403
1404PHONY += _modinst_
1405_modinst_: _builtin_inst_
1406	@rm -rf $(MODLIB)/kernel
1407	@rm -f $(MODLIB)/source
1408	@mkdir -p $(MODLIB)/kernel
1409	@ln -s $(abspath $(srctree)) $(MODLIB)/source
1410	@if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
1411		rm -f $(MODLIB)/build ; \
1412		ln -s $(CURDIR) $(MODLIB)/build ; \
1413	fi
1414	@sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order
1415	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1416
1417# This depmod is only for convenience to give the initial
1418# boot a modules.dep even before / is mounted read-write.  However the
1419# boot script depmod is the master version.
1420PHONY += _modinst_post
1421_modinst_post: _modinst_
1422	$(call cmd,depmod)
1423
1424ifeq ($(CONFIG_MODULE_SIG), y)
1425PHONY += modules_sign
1426modules_sign:
1427	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1428endif
1429
1430else # CONFIG_MODULES
1431
1432# Modules not configured
1433# ---------------------------------------------------------------------------
1434
1435PHONY += modules modules_install
1436modules modules_install:
1437	@echo >&2
1438	@echo >&2 "The present kernel configuration has modules disabled."
1439	@echo >&2 "Type 'make config' and enable loadable module support."
1440	@echo >&2 "Then build a kernel with module support enabled."
1441	@echo >&2
1442	@exit 1
1443
1444endif # CONFIG_MODULES
1445
1446###
1447# Cleaning is done on three levels.
1448# make clean     Delete most generated files
1449#                Leave enough to build external modules
1450# make mrproper  Delete the current configuration, and all generated files
1451# make distclean Remove editor backup files, patch leftover files and the like
1452
1453# Directories & files removed with 'make clean'
1454CLEAN_FILES += include/ksym vmlinux.symvers \
1455	       modules.builtin modules.builtin.modinfo modules.nsdeps
1456
1457# Directories & files removed with 'make mrproper'
1458MRPROPER_FILES += include/config include/generated          \
1459		  arch/$(SRCARCH)/include/generated .tmp_objdiff \
1460		  debian snap tar-install \
1461		  .config .config.old .version \
1462		  Module.symvers \
1463		  signing_key.pem signing_key.priv signing_key.x509	\
1464		  x509.genkey extra_certificates signing_key.x509.keyid	\
1465		  signing_key.x509.signer vmlinux-gdb.py \
1466		  *.spec
1467
1468# Directories & files removed with 'make distclean'
1469DISTCLEAN_FILES += tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS
1470
1471# clean - Delete most, but leave enough to build external modules
1472#
1473clean: rm-files := $(CLEAN_FILES)
1474
1475PHONY += archclean vmlinuxclean
1476
1477vmlinuxclean:
1478	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1479	$(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1480
1481clean: archclean vmlinuxclean
1482
1483# mrproper - Delete all generated files, including .config
1484#
1485mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1486mrproper-dirs      := $(addprefix _mrproper_,scripts)
1487
1488PHONY += $(mrproper-dirs) mrproper
1489$(mrproper-dirs):
1490	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1491
1492mrproper: clean $(mrproper-dirs)
1493	$(call cmd,rmfiles)
1494
1495# distclean
1496#
1497distclean: rm-files := $(wildcard $(DISTCLEAN_FILES))
1498
1499PHONY += distclean
1500
1501distclean: mrproper
1502	$(call cmd,rmfiles)
1503	@find $(srctree) $(RCS_FIND_IGNORE) \
1504		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1505		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
1506		-o -name 'core' \) \
1507		-type f -print | xargs rm -f
1508
1509
1510# Packaging of the kernel to various formats
1511# ---------------------------------------------------------------------------
1512
1513%src-pkg: FORCE
1514	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1515%pkg: include/config/kernel.release FORCE
1516	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1517
1518# Brief documentation of the typical targets used
1519# ---------------------------------------------------------------------------
1520
1521boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1522boards := $(sort $(notdir $(boards)))
1523board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1524board-dirs := $(sort $(notdir $(board-dirs:/=)))
1525
1526PHONY += help
1527help:
1528	@echo  'Cleaning targets:'
1529	@echo  '  clean		  - Remove most generated files but keep the config and'
1530	@echo  '                    enough build support to build external modules'
1531	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
1532	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
1533	@echo  ''
1534	@echo  'Configuration targets:'
1535	@$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1536	@echo  ''
1537	@echo  'Other generic targets:'
1538	@echo  '  all		  - Build all targets marked with [*]'
1539	@echo  '* vmlinux	  - Build the bare kernel'
1540	@echo  '* modules	  - Build all modules'
1541	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1542	@echo  '  dir/            - Build all files in dir and below'
1543	@echo  '  dir/file.[ois]  - Build specified target only'
1544	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1545	@echo  '                    (requires compiler support for LLVM assembly generation)'
1546	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1547	@echo  '                    (requires a recent binutils and recent build (System.map))'
1548	@echo  '  dir/file.ko     - Build module including final link'
1549	@echo  '  modules_prepare - Set up for building external modules'
1550	@echo  '  tags/TAGS	  - Generate tags file for editors'
1551	@echo  '  cscope	  - Generate cscope index'
1552	@echo  '  gtags           - Generate GNU GLOBAL index'
1553	@echo  '  kernelrelease	  - Output the release version string (use with make -s)'
1554	@echo  '  kernelversion	  - Output the version stored in Makefile (use with make -s)'
1555	@echo  '  image_name	  - Output the image name (use with make -s)'
1556	@echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1557	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1558	 echo  ''
1559	@echo  'Static analysers:'
1560	@echo  '  checkstack      - Generate a list of stack hogs'
1561	@echo  '  namespacecheck  - Name space analysis on compiled kernel'
1562	@echo  '  versioncheck    - Sanity check on version.h usage'
1563	@echo  '  includecheck    - Check for duplicate included header files'
1564	@echo  '  export_report   - List the usages of all exported symbols'
1565	@echo  '  headerdep       - Detect inclusion cycles in headers'
1566	@echo  '  coccicheck      - Check with Coccinelle'
1567	@echo  ''
1568	@echo  'Tools:'
1569	@echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1570	@echo  ''
1571	@echo  'Kernel selftest:'
1572	@echo  '  kselftest         - Build and run kernel selftest'
1573	@echo  '                      Build, install, and boot kernel before'
1574	@echo  '                      running kselftest on it'
1575	@echo  '                      Run as root for full coverage'
1576	@echo  '  kselftest-all     - Build kernel selftest'
1577	@echo  '  kselftest-install - Build and install kernel selftest'
1578	@echo  '  kselftest-clean   - Remove all generated kselftest files'
1579	@echo  '  kselftest-merge   - Merge all the config dependencies of'
1580	@echo  '		      kselftest to existing .config.'
1581	@echo  ''
1582	@$(if $(dtstree), \
1583		echo 'Devicetree:'; \
1584		echo '* dtbs             - Build device tree blobs for enabled boards'; \
1585		echo '  dtbs_install     - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1586		echo '  dt_binding_check - Validate device tree binding documents'; \
1587		echo '  dtbs_check       - Validate device tree source files';\
1588		echo '')
1589
1590	@echo 'Userspace tools targets:'
1591	@echo '  use "make tools/help"'
1592	@echo '  or  "cd tools; make help"'
1593	@echo  ''
1594	@echo  'Kernel packaging:'
1595	@$(MAKE) -f $(srctree)/scripts/Makefile.package help
1596	@echo  ''
1597	@echo  'Documentation targets:'
1598	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1599	@echo  ''
1600	@echo  'Architecture specific targets ($(SRCARCH)):'
1601	@$(if $(archhelp),$(archhelp),\
1602		echo '  No architecture specific help defined for $(SRCARCH)')
1603	@echo  ''
1604	@$(if $(boards), \
1605		$(foreach b, $(boards), \
1606		printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1607		echo '')
1608	@$(if $(board-dirs), \
1609		$(foreach b, $(board-dirs), \
1610		printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1611		printf "  %-16s - Show all of the above\\n" help-boards; \
1612		echo '')
1613
1614	@echo  '  make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1615	@echo  '  make V=2   [targets] 2 => give reason for rebuild of target'
1616	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1617	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1618	@echo  '                       (sparse by default)'
1619	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1620	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1621	@echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
1622	@echo  '		1: warnings which may be relevant and do not occur too often'
1623	@echo  '		2: warnings which occur quite often but may still be relevant'
1624	@echo  '		3: more obscure warnings, can most likely be ignored'
1625	@echo  '		Multiple levels can be combined with W=12 or W=123'
1626	@echo  ''
1627	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
1628	@echo  'For further info see the ./README file'
1629
1630
1631help-board-dirs := $(addprefix help-,$(board-dirs))
1632
1633help-boards: $(help-board-dirs)
1634
1635boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1636
1637$(help-board-dirs): help-%:
1638	@echo  'Architecture specific targets ($(SRCARCH) $*):'
1639	@$(if $(boards-per-dir), \
1640		$(foreach b, $(boards-per-dir), \
1641		printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1642		echo '')
1643
1644
1645# Documentation targets
1646# ---------------------------------------------------------------------------
1647DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1648	       linkcheckdocs dochelp refcheckdocs
1649PHONY += $(DOC_TARGETS)
1650$(DOC_TARGETS):
1651	$(Q)$(MAKE) $(build)=Documentation $@
1652
1653# Misc
1654# ---------------------------------------------------------------------------
1655
1656PHONY += scripts_gdb
1657scripts_gdb: prepare0
1658	$(Q)$(MAKE) $(build)=scripts/gdb
1659	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1660
1661ifdef CONFIG_GDB_SCRIPTS
1662all: scripts_gdb
1663endif
1664
1665else # KBUILD_EXTMOD
1666
1667###
1668# External module support.
1669# When building external modules the kernel used as basis is considered
1670# read-only, and no consistency checks are made and the make
1671# system is not used on the basis kernel. If updates are required
1672# in the basis kernel ordinary make commands (without M=...) must
1673# be used.
1674#
1675# The following are the only valid targets when building external
1676# modules.
1677# make M=dir clean     Delete all automatically generated files
1678# make M=dir modules   Make all modules in specified dir
1679# make M=dir	       Same as 'make M=dir modules'
1680# make M=dir modules_install
1681#                      Install the modules built in the module directory
1682#                      Assumes install directory is already created
1683
1684# We are always building modules
1685KBUILD_MODULES := 1
1686
1687build-dirs := $(KBUILD_EXTMOD)
1688PHONY += modules
1689modules: descend
1690	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1691
1692PHONY += modules_install
1693modules_install: _emodinst_ _emodinst_post
1694
1695install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1696PHONY += _emodinst_
1697_emodinst_:
1698	$(Q)mkdir -p $(MODLIB)/$(install-dir)
1699	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1700
1701PHONY += _emodinst_post
1702_emodinst_post: _emodinst_
1703	$(call cmd,depmod)
1704
1705clean-dirs := $(KBUILD_EXTMOD)
1706clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps
1707
1708PHONY += help
1709help:
1710	@echo  '  Building external modules.'
1711	@echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1712	@echo  ''
1713	@echo  '  modules         - default target, build the module(s)'
1714	@echo  '  modules_install - install the module'
1715	@echo  '  clean           - remove generated files in module directory only'
1716	@echo  ''
1717
1718PHONY += prepare
1719endif # KBUILD_EXTMOD
1720
1721# Single targets
1722# ---------------------------------------------------------------------------
1723# To build individual files in subdirectories, you can do like this:
1724#
1725#   make foo/bar/baz.s
1726#
1727# The supported suffixes for single-target are listed in 'single-targets'
1728#
1729# To build only under specific subdirectories, you can do like this:
1730#
1731#   make foo/bar/baz/
1732
1733ifdef single-build
1734
1735# .ko is special because modpost is needed
1736single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1737single-no-ko := $(sort $(patsubst %.ko,%.mod, $(MAKECMDGOALS)))
1738
1739$(single-ko): single_modpost
1740	@:
1741$(single-no-ko): descend
1742	@:
1743
1744ifeq ($(KBUILD_EXTMOD),)
1745# For the single build of in-tree modules, use a temporary file to avoid
1746# the situation of modules_install installing an invalid modules.order.
1747MODORDER := .modules.tmp
1748endif
1749
1750PHONY += single_modpost
1751single_modpost: $(single-no-ko)
1752	$(Q){ $(foreach m, $(single-ko), echo $(extmod-prefix)$m;) } > $(MODORDER)
1753	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1754
1755KBUILD_MODULES := 1
1756
1757export KBUILD_SINGLE_TARGETS := $(addprefix $(extmod-prefix), $(single-no-ko))
1758
1759# trim unrelated directories
1760build-dirs := $(foreach d, $(build-dirs), \
1761			$(if $(filter $(d)/%, $(KBUILD_SINGLE_TARGETS)), $(d)))
1762
1763endif
1764
1765ifndef CONFIG_MODULES
1766KBUILD_MODULES :=
1767endif
1768
1769# Handle descending into subdirectories listed in $(build-dirs)
1770# Preset locale variables to speed up the build process. Limit locale
1771# tweaks to this spot to avoid wrong language settings when running
1772# make menuconfig etc.
1773# Error messages still appears in the original language
1774PHONY += descend $(build-dirs)
1775descend: $(build-dirs)
1776$(build-dirs): prepare
1777	$(Q)$(MAKE) $(build)=$@ \
1778	single-build=$(if $(filter-out $@/, $(filter $@/%, $(single-no-ko))),1) \
1779	need-builtin=1 need-modorder=1
1780
1781clean-dirs := $(addprefix _clean_, $(clean-dirs))
1782PHONY += $(clean-dirs) clean
1783$(clean-dirs):
1784	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1785
1786clean: $(clean-dirs)
1787	$(call cmd,rmfiles)
1788	@find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1789		\( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1790		-o -name '*.ko.*' \
1791		-o -name '*.dtb' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1792		-o -name '*.dwo' -o -name '*.lst' \
1793		-o -name '*.su' -o -name '*.mod' \
1794		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1795		-o -name '*.lex.c' -o -name '*.tab.[ch]' \
1796		-o -name '*.asn1.[ch]' \
1797		-o -name '*.symtypes' -o -name 'modules.order' \
1798		-o -name '.tmp_*.o.*' \
1799		-o -name '*.c.[012]*.*' \
1800		-o -name '*.ll' \
1801		-o -name '*.gcno' \) -type f -print | xargs rm -f
1802
1803# Generate tags for editors
1804# ---------------------------------------------------------------------------
1805quiet_cmd_tags = GEN     $@
1806      cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1807
1808tags TAGS cscope gtags: FORCE
1809	$(call cmd,tags)
1810
1811# Script to generate missing namespace dependencies
1812# ---------------------------------------------------------------------------
1813
1814PHONY += nsdeps
1815nsdeps: export KBUILD_NSDEPS=1
1816nsdeps: modules
1817	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1818
1819# Scripts to check various things for consistency
1820# ---------------------------------------------------------------------------
1821
1822PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1823
1824includecheck:
1825	find $(srctree)/* $(RCS_FIND_IGNORE) \
1826		-name '*.[hcS]' -type f -print | sort \
1827		| xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1828
1829versioncheck:
1830	find $(srctree)/* $(RCS_FIND_IGNORE) \
1831		-name '*.[hcS]' -type f -print | sort \
1832		| xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1833
1834coccicheck:
1835	$(Q)$(BASH) $(srctree)/scripts/$@
1836
1837namespacecheck:
1838	$(PERL) $(srctree)/scripts/namespace.pl
1839
1840export_report:
1841	$(PERL) $(srctree)/scripts/export_report.pl
1842
1843PHONY += checkstack kernelrelease kernelversion image_name
1844
1845# UML needs a little special treatment here.  It wants to use the host
1846# toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
1847# else wants $(ARCH), including people doing cross-builds, which means
1848# that $(SUBARCH) doesn't work here.
1849ifeq ($(ARCH), um)
1850CHECKSTACK_ARCH := $(SUBARCH)
1851else
1852CHECKSTACK_ARCH := $(ARCH)
1853endif
1854checkstack:
1855	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1856	$(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1857
1858kernelrelease:
1859	@echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1860
1861kernelversion:
1862	@echo $(KERNELVERSION)
1863
1864image_name:
1865	@echo $(KBUILD_IMAGE)
1866
1867# Clear a bunch of variables before executing the submake
1868
1869ifeq ($(quiet),silent_)
1870tools_silent=s
1871endif
1872
1873tools/: FORCE
1874	$(Q)mkdir -p $(objtree)/tools
1875	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1876
1877tools/%: FORCE
1878	$(Q)mkdir -p $(objtree)/tools
1879	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1880
1881quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
1882      cmd_rmfiles = rm -rf $(rm-files)
1883
1884# Run depmod only if we have System.map and depmod is executable
1885quiet_cmd_depmod = DEPMOD  $(KERNELRELEASE)
1886      cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1887                   $(KERNELRELEASE)
1888
1889# read saved command lines for existing targets
1890existing-targets := $(wildcard $(sort $(targets)))
1891
1892-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
1893
1894endif # config-build
1895endif # mixed-build
1896endif # need-sub-make
1897
1898PHONY += FORCE
1899FORCE:
1900
1901# Declare the contents of the PHONY variable as phony.  We keep that
1902# information in a variable so we can use it in if_changed and friends.
1903.PHONY: $(PHONY)
1904