Makefile 59.5 KB
Newer Older
1
# SPDX-License-Identifier: GPL-2.0
Linus Torvalds's avatar
Linus Torvalds committed
2
VERSION = 5
Linus Torvalds's avatar
Linus Torvalds committed
3
PATCHLEVEL = 4
Linus Torvalds's avatar
Linus Torvalds committed
4
SUBLEVEL = 0
Linus Torvalds's avatar
Linus Torvalds committed
5
EXTRAVERSION = -rc8
Linus Torvalds's avatar
Linus Torvalds committed
6
NAME = Kleptomaniac Octopus
Linus Torvalds's avatar
Linus Torvalds committed
7 8 9 10 11 12 13

# *DOCUMENTATION*
# To see a list of typical targets execute "make help"
# More info can be located in ./README
# Comments in this file are targeted only to the developer, do not
# expect to learn how to build the kernel reading this file.

14 15 16 17
# That's our default target when none is given on the command line
PHONY := _all
_all:

Linus Torvalds's avatar
Linus Torvalds committed
18 19 20 21 22 23
# We are using a recursive build, so we need to do a little thinking
# to get the ordering right.
#
# Most importantly: sub-Makefiles should only ever modify files in
# their own directory. If in some directory we have a dependency on
# 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
Linus Torvalds's avatar
Linus Torvalds committed
25 26 27 28 29 30 31 32 33
# turn into vmlinux), we will call a sub make in that other dir, and
# after that we are sure that everything which is in that other dir
# is now up to date.
#
# The only cases where we need to modify files which have global
# effects are thus separated out and done before the recursive
# descending is started. They are now explicitly listed as the
# prepare rule.

34
ifneq ($(sub_make_done),1)
35 36 37 38 39 40 41 42 43 44 45 46 47 48

# Do not use make's built-in rules and variables
# (this increases performance and avoids hard-to-debug behaviour)
MAKEFLAGS += -rR

# Avoid funny character set dependencies
unexport LC_ALL
LC_COLLATE=C
LC_NUMERIC=C
export LC_COLLATE LC_NUMERIC

# Avoid interference with shell env settings
unexport GREP_OPTIONS

49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71
# Beautify output
# ---------------------------------------------------------------------------
#
# Normally, we echo the whole command before executing it. By making
# that echo $($(quiet)$(cmd)), we now have the possibility to set
# $(quiet) to choose other forms of output instead, e.g.
#
#         quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
#         cmd_cc_o_c       = $(CC) $(c_flags) -c -o $@ $<
#
# If $(quiet) is empty, the whole command will be printed.
# If it is set to "quiet_", only the short version will be printed.
# If it is set to "silent_", nothing will be printed at all, since
# the variable $(silent_cmd_cc_o_c) doesn't exist.
#
# A simple variant is to prefix commands with $(Q) - that's useful
# for commands that shall be hidden in non-verbose mode.
#
#	$(Q)ln $@ :<
#
# If KBUILD_VERBOSE equals 0 then the above command will be hidden.
# If KBUILD_VERBOSE equals 1 then the above command is displayed.
#
Linus Torvalds's avatar
Linus Torvalds committed
72 73 74
# To put more focus on warnings, be less verbose as default
# Use 'make V=1' to see the full commands

75 76
ifeq ("$(origin V)", "command line")
  KBUILD_VERBOSE = $(V)
Linus Torvalds's avatar
Linus Torvalds committed
77 78 79 80 81
endif
ifndef KBUILD_VERBOSE
  KBUILD_VERBOSE = 0
endif

82 83 84 85 86 87 88 89 90 91 92
ifeq ($(KBUILD_VERBOSE),1)
  quiet =
  Q =
else
  quiet=quiet_
  Q = @
endif

# If the user is running make -s (silent mode), suppress echoing of
# commands

93
ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
94 95 96 97 98
  quiet=silent_
endif

export quiet Q KBUILD_VERBOSE

99 100 101 102 103 104 105 106 107 108
# Kbuild will save output files in the current working directory.
# This does not need to match to the root of the kernel source tree.
#
# For example, you can do this:
#
#  cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
#
# If you want to save output files in a different location, there are
# two syntaxes to specify it.
#
Linus Torvalds's avatar
Linus Torvalds committed
109 110
# 1) O=
# Use "make O=dir/to/store/output/files/"
111
#
Linus Torvalds's avatar
Linus Torvalds committed
112
# 2) Set KBUILD_OUTPUT
113 114
# Set the environment variable KBUILD_OUTPUT to point to the output directory.
# export KBUILD_OUTPUT=dir/to/store/output/files/; make
Linus Torvalds's avatar
Linus Torvalds committed
115 116 117 118
#
# The O= assignment takes precedence over the KBUILD_OUTPUT environment
# variable.

119
# Do we want to change the working directory?
120 121
ifeq ("$(origin O)", "command line")
  KBUILD_OUTPUT := $(O)
Linus Torvalds's avatar
Linus Torvalds committed
122 123
endif

124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141
ifneq ($(KBUILD_OUTPUT),)
# Make's built-in functions such as $(abspath ...), $(realpath ...) cannot
# expand a shell special character '~'. We use a somewhat tedious way here.
abs_objtree := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) && pwd)
$(if $(abs_objtree),, \
     $(error failed to create output directory "$(KBUILD_OUTPUT)"))

# $(realpath ...) resolves symlinks
abs_objtree := $(realpath $(abs_objtree))
else
abs_objtree := $(CURDIR)
endif # ifneq ($(KBUILD_OUTPUT),)

ifeq ($(abs_objtree),$(CURDIR))
# Suppress "Entering directory ..." unless we are changing the work directory.
MAKEFLAGS += --no-print-directory
else
need-sub-make := 1
142 143
endif

144
abs_srctree := $(realpath $(dir $(lastword $(MAKEFILE_LIST))))
Linus Torvalds's avatar
Linus Torvalds committed
145

146 147 148
ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
$(error source directory cannot contain spaces or colons)
endif
Linus Torvalds's avatar
Linus Torvalds committed
149

150
ifneq ($(abs_srctree),$(abs_objtree))
151 152 153
# Look for make include files relative to root of kernel src
#
# This does not become effective immediately because MAKEFLAGS is re-parsed
154 155
# once after the Makefile is read. We need to invoke sub-make.
MAKEFLAGS += --include-dir=$(abs_srctree)
156
need-sub-make := 1
157
endif
158

159 160 161 162 163 164 165 166
ifneq ($(filter 3.%,$(MAKE_VERSION)),)
# 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
# We need to invoke sub-make to avoid implicit rules in the top Makefile.
need-sub-make := 1
# Cancel implicit rules for this Makefile.
$(lastword $(MAKEFILE_LIST)): ;
endif

167
export abs_srctree abs_objtree
168 169
export sub_make_done := 1

170 171
ifeq ($(need-sub-make),1)

172 173
PHONY += $(MAKECMDGOALS) sub-make

174
$(filter-out _all sub-make $(lastword $(MAKEFILE_LIST)), $(MAKECMDGOALS)) _all: sub-make
175
	@:
176

177
# Invoke a second make in the output directory, passing relevant variables
178
sub-make:
179
	$(Q)$(MAKE) -C $(abs_objtree) -f $(abs_srctree)/Makefile $(MAKECMDGOALS)
Linus Torvalds's avatar
Linus Torvalds committed
180

181
endif # need-sub-make
182
endif # sub_make_done
183

Linus Torvalds's avatar
Linus Torvalds committed
184
# We process the rest of the Makefile if this is the final invocation of make
185
ifeq ($(need-sub-make),)
Linus Torvalds's avatar
Linus Torvalds committed
186

187 188 189 190 191
# Do not print "Entering directory ...",
# but we want to display it when entering to the output directory
# so that IDEs/editors are able to understand relative filenames.
MAKEFLAGS += --no-print-directory

192 193 194 195 196 197 198
# Call a source code checker (by default, "sparse") as part of the
# C compilation.
#
# Use 'make C=1' to enable checking of only re-compiled files.
# Use 'make C=2' to enable checking of *all* source files, regardless
# of whether they are re-compiled or not.
#
Cao jin's avatar
Cao jin committed
199 200
# See the file "Documentation/dev-tools/sparse.rst" for more details,
# including where to get the "sparse" utility.
201 202 203 204 205 206 207 208

ifeq ("$(origin C)", "command line")
  KBUILD_CHECKSRC = $(C)
endif
ifndef KBUILD_CHECKSRC
  KBUILD_CHECKSRC = 0
endif

209 210
# Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
# directory of external module to build. Setting M= takes precedence.
211 212 213 214
ifeq ("$(origin M)", "command line")
  KBUILD_EXTMOD := $(M)
endif

215 216
export KBUILD_CHECKSRC KBUILD_EXTMOD

217 218
extmod-prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)

219
ifeq ($(abs_srctree),$(abs_objtree))
220 221
        # building in the source tree
        srctree := .
222
	building_out_of_srctree :=
223
else
224
        ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
225 226 227
                # building in a subdirectory of the source tree
                srctree := ..
        else
228
                srctree := $(abs_srctree)
229
        endif
230
	building_out_of_srctree := 1
231
endif
232

233 234 235
ifneq ($(KBUILD_ABS_SRCTREE),)
srctree := $(abs_srctree)
endif
236

237
objtree		:= .
238
VPATH		:= $(srctree)
Linus Torvalds's avatar
Linus Torvalds committed
239

240
export building_out_of_srctree srctree objtree VPATH
Linus Torvalds's avatar
Linus Torvalds committed
241

242 243 244 245 246 247 248 249 250 251 252
# To make sure we do not include .config for any of the *config targets
# catch them early, and hand them over to scripts/kconfig/Makefile
# It is allowed to specify more targets when calling make, including
# mixing *config targets and build targets.
# For example 'make oldconfig all'.
# Detect when mixed targets is specified, and make a second invocation
# of make so .config is not included in this case either (for *config).

version_h := include/generated/uapi/linux/version.h
old_version_h := include/linux/version.h

253 254
clean-targets := %clean mrproper cleandocs
no-dot-config-targets := $(clean-targets) \
255
			 cscope gtags TAGS tags help% %docs check% coccicheck \
256
			 $(version_h) headers headers_% archheaders archscripts \
257
			 %asm-generic kernelversion %src-pkg
258 259
no-sync-config-targets := $(no-dot-config-targets) install %install \
			   kernelrelease
260
single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
261

262 263 264 265
config-build	:=
mixed-build	:=
need-config	:= 1
may-sync-config	:= 1
266
single-build	:=
267 268 269

ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
	ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
270
		need-config :=
271 272 273
	endif
endif

274 275
ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
	ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
276
		may-sync-config :=
277 278 279 280
	endif
endif

ifneq ($(KBUILD_EXTMOD),)
281
	may-sync-config :=
282 283
endif

284 285
ifeq ($(KBUILD_EXTMOD),)
        ifneq ($(filter config %config,$(MAKECMDGOALS)),)
286
		config-build := 1
287
                ifneq ($(words $(MAKECMDGOALS)),1)
288
			mixed-build := 1
289 290 291
                endif
        endif
endif
292

293 294 295 296 297 298 299 300
# We cannot build single targets and the others at the same time
ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
	single-build := 1
	ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
		mixed-build := 1
	endif
endif

301 302 303
# For "make -j clean all", "make -j mrproper defconfig all", etc.
ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
        ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
304
		mixed-build := 1
305 306 307
        endif
endif

308 309 310
# install and modules_install need also be processed one by one
ifneq ($(filter install,$(MAKECMDGOALS)),)
        ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
311
		mixed-build := 1
312 313 314
        endif
endif

315
ifdef mixed-build
316 317 318 319 320 321 322 323 324 325 326 327 328 329 330
# ===========================================================================
# We're called with mixed targets (*config and build targets).
# Handle them one by one.

PHONY += $(MAKECMDGOALS) __build_one_by_one

$(filter-out __build_one_by_one, $(MAKECMDGOALS)): __build_one_by_one
	@:

__build_one_by_one:
	$(Q)set -e; \
	for i in $(MAKECMDGOALS); do \
		$(MAKE) -f $(srctree)/Makefile $$i; \
	done

331
else # !mixed-build
332 333 334 335 336 337 338 339

include scripts/Kbuild.include

# Read KERNELRELEASE from include/config/kernel.release (if it exists)
KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION

340
include scripts/subarch.include
Linus Torvalds's avatar
Linus Torvalds committed
341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359

# Cross compiling and selecting different set of gcc/bin-utils
# ---------------------------------------------------------------------------
#
# When performing cross compilation for other architectures ARCH shall be set
# to the target architecture. (See arch/* for the possibilities).
# ARCH can be set during invocation of make:
# make ARCH=ia64
# Another way is to have ARCH set in the environment.
# The default ARCH is the host where make is executed.

# CROSS_COMPILE specify the prefix used for all executables used
# during compilation. Only gcc and related bin-utils executables
# are prefixed with $(CROSS_COMPILE).
# CROSS_COMPILE can be set on the command line
# make CROSS_COMPILE=ia64-linux-
# Alternatively CROSS_COMPILE can be set in the environment.
# Default value for CROSS_COMPILE is not to prefix executables
# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
360
ARCH		?= $(SUBARCH)
Linus Torvalds's avatar
Linus Torvalds committed
361 362

# Architecture as present in compile.h
363 364
UTS_MACHINE 	:= $(ARCH)
SRCARCH 	:= $(ARCH)
Linus Torvalds's avatar
Linus Torvalds committed
365

366 367 368 369 370 371 372
# Additional ARCH settings for x86
ifeq ($(ARCH),i386)
        SRCARCH := x86
endif
ifeq ($(ARCH),x86_64)
        SRCARCH := x86
endif
373

Sam Ravnborg's avatar
Sam Ravnborg committed
374
# Additional ARCH settings for sparc
375 376 377
ifeq ($(ARCH),sparc32)
       SRCARCH := sparc
endif
378
ifeq ($(ARCH),sparc64)
Sam Ravnborg's avatar
Sam Ravnborg committed
379
       SRCARCH := sparc
380
endif
381

382 383 384 385 386
# Additional ARCH settings for sh
ifeq ($(ARCH),sh64)
       SRCARCH := sh
endif

387
KCONFIG_CONFIG	?= .config
388
export KCONFIG_CONFIG
389

Linus Torvalds's avatar
Linus Torvalds committed
390
# SHELL used by kbuild
391
CONFIG_SHELL := sh
Linus Torvalds's avatar
Linus Torvalds committed
392

393 394 395
HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
396

397 398
HOSTCC       = gcc
HOSTCXX      = g++
399
KBUILD_HOSTCFLAGS   := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 \
400 401 402 403 404
		-fomit-frame-pointer -std=gnu89 $(HOST_LFS_CFLAGS) \
		$(HOSTCFLAGS)
KBUILD_HOSTCXXFLAGS := -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
Linus Torvalds's avatar
Linus Torvalds committed
405 406 407 408 409 410 411 412 413 414 415

# Make variables (CC, etc...)
AS		= $(CROSS_COMPILE)as
LD		= $(CROSS_COMPILE)ld
CC		= $(CROSS_COMPILE)gcc
CPP		= $(CC) -E
AR		= $(CROSS_COMPILE)ar
NM		= $(CROSS_COMPILE)nm
STRIP		= $(CROSS_COMPILE)strip
OBJCOPY		= $(CROSS_COMPILE)objcopy
OBJDUMP		= $(CROSS_COMPILE)objdump
416
OBJSIZE		= $(CROSS_COMPILE)size
417
PAHOLE		= pahole
418 419
LEX		= flex
YACC		= bison
Linus Torvalds's avatar
Linus Torvalds committed
420
AWK		= awk
421
INSTALLKERNEL  := installkernel
Linus Torvalds's avatar
Linus Torvalds committed
422 423
DEPMOD		= /sbin/depmod
PERL		= perl
424
PYTHON		= python
425 426
PYTHON2		= python2
PYTHON3		= python3
Linus Torvalds's avatar
Linus Torvalds committed
427
CHECK		= sparse
428
BASH		= bash
Linus Torvalds's avatar
Linus Torvalds committed
429

430
CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
431
		  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
432
NOSTDINC_FLAGS :=
433 434 435
CFLAGS_MODULE   =
AFLAGS_MODULE   =
LDFLAGS_MODULE  =
Linus Torvalds's avatar
Linus Torvalds committed
436 437
CFLAGS_KERNEL	=
AFLAGS_KERNEL	=
438
LDFLAGS_vmlinux =
Linus Torvalds's avatar
Linus Torvalds committed
439

440 441
# Use USERINCLUDE when you must reference the UAPI directories only.
USERINCLUDE    := \
442 443
		-I$(srctree)/arch/$(SRCARCH)/include/uapi \
		-I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
444
		-I$(srctree)/include/uapi \
445
		-I$(objtree)/include/generated/uapi \
446 447
                -include $(srctree)/include/linux/kconfig.h

Linus Torvalds's avatar
Linus Torvalds committed
448 449
# Use LINUXINCLUDE when you must reference the include/ directory.
# Needed to be compatible with the O= option
450
LINUXINCLUDE    := \
451 452
		-I$(srctree)/arch/$(SRCARCH)/include \
		-I$(objtree)/arch/$(SRCARCH)/include/generated \
453
		$(if $(building_out_of_srctree),-I$(srctree)/include) \
454 455
		-I$(objtree)/include \
		$(USERINCLUDE)
Linus Torvalds's avatar
Linus Torvalds committed
456

457
KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
458
KBUILD_CFLAGS   := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
459
		   -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
460
		   -Werror=implicit-function-declaration -Werror=implicit-int \
461
		   -Wno-format-security \
462 463
		   -std=gnu89
KBUILD_CPPFLAGS := -D__KERNEL__
464 465
KBUILD_AFLAGS_KERNEL :=
KBUILD_CFLAGS_KERNEL :=
466 467
KBUILD_AFLAGS_MODULE  := -DMODULE
KBUILD_CFLAGS_MODULE  := -DMODULE
468 469
KBUILD_LDFLAGS_MODULE :=
export KBUILD_LDS_MODULE := $(srctree)/scripts/module-common.lds
470
KBUILD_LDFLAGS :=
471
GCC_PLUGINS_CFLAGS :=
472
CLANG_FLAGS :=
Linus Torvalds's avatar
Linus Torvalds committed
473

474
export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE AS LD CC
475 476 477
export CPP AR NM STRIP OBJCOPY OBJDUMP OBJSIZE PAHOLE LEX YACC AWK INSTALLKERNEL
export PERL PYTHON PYTHON2 PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
Linus Torvalds's avatar
Linus Torvalds committed
478

479
export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
480 481
export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN
482
export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
483
export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
484
export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
Linus Torvalds's avatar
Linus Torvalds committed
485 486 487

# Files to ignore in find ... statements

488 489 490
export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
			  -name CVS -o -name .pc -o -name .hg -o -name .git \) \
			  -prune -o
491 492
export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
			 --exclude CVS --exclude .pc --exclude .hg --exclude .git
Linus Torvalds's avatar
Linus Torvalds committed
493 494 495 496

# ===========================================================================
# Rules shared between *config targets and build targets

497
# Basic helpers built in scripts/basic/
498
PHONY += scripts_basic
Linus Torvalds's avatar
Linus Torvalds committed
499 500
scripts_basic:
	$(Q)$(MAKE) $(build)=scripts/basic
501
	$(Q)rm -f .tmp_quiet_recordmcount
Linus Torvalds's avatar
Linus Torvalds committed
502

503
PHONY += outputmakefile
504
# Before starting out-of-tree build, make sure the source tree is clean.
505 506 507
# outputmakefile generates a Makefile in the output directory, if using a
# separate output directory. This allows convenient use of make in the
# output directory.
508 509
# At the same time when output Makefile generated, generate .gitignore to
# ignore whole output directory
Linus Torvalds's avatar
Linus Torvalds committed
510
outputmakefile:
511
ifdef building_out_of_srctree
512 513 514 515 516 517 518 519 520
	$(Q)if [ -f $(srctree)/.config -o \
		 -d $(srctree)/include/config -o \
		 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
		echo >&2 "***"; \
		echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
		echo >&2 "*** in $(abs_srctree)";\
		echo >&2 "***"; \
		false; \
	fi
521
	$(Q)ln -fsn $(srctree) source
522
	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile $(srctree)
523 524
	$(Q)test -e .gitignore || \
	{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
525
endif
Linus Torvalds's avatar
Linus Torvalds committed
526

527
ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),)
528
ifneq ($(CROSS_COMPILE),)
529
CLANG_FLAGS	+= --target=$(notdir $(CROSS_COMPILE:%-=%))
530
GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
531
CLANG_FLAGS	+= --prefix=$(GCC_TOOLCHAIN_DIR)
532
GCC_TOOLCHAIN	:= $(realpath $(GCC_TOOLCHAIN_DIR)/..)
533 534
endif
ifneq ($(GCC_TOOLCHAIN),)
535
CLANG_FLAGS	+= --gcc-toolchain=$(GCC_TOOLCHAIN)
536
endif
537
ifeq ($(shell $(AS) --version 2>&1 | head -n 1 | grep clang),)
538
CLANG_FLAGS	+= -no-integrated-as
539
endif
540
CLANG_FLAGS	+= -Werror=unknown-warning-option
541 542
KBUILD_CFLAGS	+= $(CLANG_FLAGS)
KBUILD_AFLAGS	+= $(CLANG_FLAGS)
543
export CLANG_FLAGS
544 545
endif

546 547 548 549
# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
# and from include/config/auto.conf.cmd to detect the compiler upgrade.
550
CC_VERSION_TEXT = $(shell $(CC) --version 2>/dev/null | head -n 1)
551

552
ifdef config-build
Linus Torvalds's avatar
Linus Torvalds committed
553 554 555 556 557 558 559
# ===========================================================================
# *config targets only - make sure prerequisites are updated, and descend
# in scripts/kconfig to make the *config target

# Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
# KBUILD_DEFCONFIG may point out an alternative default configuration
# used for 'make defconfig'
560
include arch/$(SRCARCH)/Makefile
561
export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
Linus Torvalds's avatar
Linus Torvalds committed
562

563
config: outputmakefile scripts_basic FORCE
564 565
	$(Q)$(MAKE) $(build)=scripts/kconfig $@

566
%config: outputmakefile scripts_basic FORCE
Linus Torvalds's avatar
Linus Torvalds committed
567 568
	$(Q)$(MAKE) $(build)=scripts/kconfig $@

569
else #!config-build
Linus Torvalds's avatar
Linus Torvalds committed
570 571 572 573
# ===========================================================================
# Build targets only - this includes vmlinux, arch specific targets, clean
# targets and others. In general all targets except *config targets.

574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601
# If building an external module we do not care about the all: rule
# but instead _all depend on modules
PHONY += all
ifeq ($(KBUILD_EXTMOD),)
_all: all
else
_all: modules
endif

# Decide whether to build built-in, modular, or both.
# Normally, just do built-in.

KBUILD_MODULES :=
KBUILD_BUILTIN := 1

# If we have only "make modules", don't compile built-in objects.
# When we're building modules with modversions, we need to consider
# the built-in objects during the descend as well, in order to
# make sure the checksums are up to date before we record them.

ifeq ($(MAKECMDGOALS),modules)
  KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
endif

# If we have "make <whatever> modules", compile modules
# in addition to whatever we do anyway.
# Just "make" or "make all" shall build modules as well

602
ifneq ($(filter all _all modules nsdeps,$(MAKECMDGOALS)),)
603 604 605 606 607 608 609 610 611
  KBUILD_MODULES := 1
endif

ifeq ($(MAKECMDGOALS),)
  KBUILD_MODULES := 1
endif

export KBUILD_MODULES KBUILD_BUILTIN

612
ifdef need-config
613 614 615
include include/config/auto.conf
endif

Linus Torvalds's avatar
Linus Torvalds committed
616 617 618
ifeq ($(KBUILD_EXTMOD),)
# Objects we will link into vmlinux / subdirs we need to visit
init-y		:= init/
619
drivers-y	:= drivers/ sound/
620
drivers-$(CONFIG_SAMPLES) += samples/
621
drivers-$(CONFIG_KERNEL_HEADER_TEST) += include/
Linus Torvalds's avatar
Linus Torvalds committed
622 623 624
net-y		:= net/
libs-y		:= lib/
core-y		:= usr/
625
virt-y		:= virt/
Linus Torvalds's avatar
Linus Torvalds committed
626 627
endif # KBUILD_EXTMOD

628 629 630 631 632 633 634 635 636
# The all: target is the default when no target is given on the
# command line.
# This allow a user to issue only 'make' to build a kernel including modules
# Defaults to vmlinux, but the arch makefile usually adds further targets
all: vmlinux

CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage \
	$(call cc-option,-fno-tree-loop-im) \
	$(call cc-disable-warning,maybe-uninitialized,)
637
export CFLAGS_GCOV
638

639 640 641 642 643
# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
ifdef CONFIG_FUNCTION_TRACER
  CC_FLAGS_FTRACE := -pg
endif

644 645 646 647 648 649 650 651 652
RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
export RETPOLINE_CFLAGS
export RETPOLINE_VDSO_CFLAGS

653
include arch/$(SRCARCH)/Makefile
Linus Torvalds's avatar
Linus Torvalds committed
654

655 656
ifdef need-config
ifdef may-sync-config
657 658 659
# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
# because some architectures define CROSS_COMPILE there.
660
include include/config/auto.conf.cmd
Linus Torvalds's avatar
Linus Torvalds committed
661

662 663 664 665 666 667 668 669
$(KCONFIG_CONFIG):
	@echo >&2 '***'
	@echo >&2 '*** Configuration file "$@" not found!'
	@echo >&2 '***'
	@echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
	@echo >&2 '*** "make menuconfig" or "make xconfig").'
	@echo >&2 '***'
	@/bin/false
Linus Torvalds's avatar
Linus Torvalds committed
670

671 672 673
# The actual configuration files used during the build are stored in
# include/generated/ and include/config/. Update them if .config is newer than
# include/config/auto.conf (which mirrors .config).
674 675 676 677
#
# This exploits the 'multi-target pattern rule' trick.
# The syncconfig should be executed only once to make all the targets.
%/auto.conf %/auto.conf.cmd %/tristate.conf: $(KCONFIG_CONFIG)
678
	$(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
679
else # !may-sync-config
680 681 682
# External modules and some install targets need include/generated/autoconf.h
# and include/config/auto.conf but do not care if they are up-to-date.
# Use auto.conf to trigger the test
683 684 685
PHONY += include/config/auto.conf

include/config/auto.conf:
686
	$(Q)test -e include/generated/autoconf.h -a -e $@ || (		\
687 688 689 690 691
	echo >&2;							\
	echo >&2 "  ERROR: Kernel configuration is invalid.";		\
	echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
	echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";	\
	echo >&2 ;							\
692 693
	/bin/false)

694
endif # may-sync-config
695
endif # need-config
Linus Torvalds's avatar
Linus Torvalds committed
696

697
KBUILD_CFLAGS	+= $(call cc-option,-fno-delete-null-pointer-checks,)
698
KBUILD_CFLAGS	+= $(call cc-disable-warning,frame-address,)
699 700
KBUILD_CFLAGS	+= $(call cc-disable-warning, format-truncation)
KBUILD_CFLAGS	+= $(call cc-disable-warning, format-overflow)
701
KBUILD_CFLAGS	+= $(call cc-disable-warning, address-of-packed-member)
702

703 704 705 706 707 708
ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
KBUILD_CFLAGS += -O2
else ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3
KBUILD_CFLAGS += -O3
else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
KBUILD_CFLAGS += -Os
709
endif
Linus Torvalds's avatar
Linus Torvalds committed
710

711 712 713
ifdef CONFIG_CC_DISABLE_WARN_MAYBE_UNINITIALIZED
KBUILD_CFLAGS   += -Wno-maybe-uninitialized
endif
714

715 716 717
# Tell gcc to never replace conditional load with a non-conditional one
KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)

718
include scripts/Makefile.kcov
Emese Revfy's avatar
Emese Revfy committed
719 720
include scripts/Makefile.gcc-plugins

Andi Kleen's avatar
Andi Kleen committed
721 722 723 724 725 726 727 728 729 730
ifdef CONFIG_READABLE_ASM
# Disable optimizations that make assembler listings hard to read.
# reorder blocks reorders the control in the function
# ipa clone creates specialized cloned functions
# partial inlining inlines only parts of functions
KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
                 $(call cc-option,-fno-ipa-cp-clone,) \
                 $(call cc-option,-fno-partial-inlining)
endif

731
ifneq ($(CONFIG_FRAME_WARN),0)
732 733 734
KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
endif

735
stackp-flags-$(CONFIG_CC_HAS_STACKPROTECTOR_NONE) := -fno-stack-protector
736 737
stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
738 739

KBUILD_CFLAGS += $(stackp-flags-y)
740

741
ifdef CONFIG_CC_IS_CLANG
742 743 744
KBUILD_CPPFLAGS += -Qunused-arguments
KBUILD_CFLAGS += -Wno-format-invalid-specifier
KBUILD_CFLAGS += -Wno-gnu
745
# Quiet clang warning: comparison of unsigned expression < 0 is always false
746
KBUILD_CFLAGS += -Wno-tautological-compare
747 748 749
# CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
# source of a reference will be _MergedGlobals and not on of the whitelisted names.
# See modpost pattern 2
750
KBUILD_CFLAGS += -mno-global-merge
751 752 753 754
else

# These warnings generated too much noise in a regular build.
# Use make W=1 to enable them (see scripts/Makefile.extrawarn)
755
KBUILD_CFLAGS += -Wno-unused-but-set-variable
756 757 758 759 760

# Warn about unmarked fall-throughs in switch statement.
# Disabled for clang while comment to attribute conversion happens and
# https://github.com/ClangBuiltLinux/linux/issues/636 is discussed.
KBUILD_CFLAGS += $(call cc-option,-Wimplicit-fallthrough,)
761 762
endif

763
KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
Linus Torvalds's avatar
Linus Torvalds committed
764
ifdef CONFIG_FRAME_POINTER
765
KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
Linus Torvalds's avatar
Linus Torvalds committed
766
else
767 768 769 770 771 772
# Some targets (ARM with Thumb2, for example), can't be built with frame
# pointers.  For those, we don't have FUNCTION_TRACER automatically
# select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
# incompatible with -fomit-frame-pointer with current GCC, so we don't use
# -fomit-frame-pointer with FUNCTION_TRACER.
ifndef CONFIG_FUNCTION_TRACER
773
KBUILD_CFLAGS	+= -fomit-frame-pointer
Linus Torvalds's avatar
Linus Torvalds committed
774
endif
775
endif
Linus Torvalds's avatar
Linus Torvalds committed
776

777 778 779 780 781
# Initialize all stack variables with a pattern, if desired.
ifdef CONFIG_INIT_STACK_ALL
KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
endif

782
DEBUG_CFLAGS	:= $(call cc-option, -fno-var-tracking-assignments)
783

Linus Torvalds's avatar
Linus Torvalds committed
784
ifdef CONFIG_DEBUG_INFO
785
ifdef CONFIG_DEBUG_INFO_SPLIT
786
DEBUG_CFLAGS	+= -gsplit-dwarf
787
else
788
DEBUG_CFLAGS	+= -g
789
endif
790
KBUILD_AFLAGS	+= -Wa,-gdwarf-2
Linus Torvalds's avatar
Linus Torvalds committed
791
endif
792
ifdef CONFIG_DEBUG_INFO_DWARF4
793
DEBUG_CFLAGS	+= -gdwarf-4
794
endif
Linus Torvalds's avatar
Linus Torvalds committed
795

796
ifdef CONFIG_DEBUG_INFO_REDUCED
797
DEBUG_CFLAGS	+= $(call cc-option, -femit-struct-debug-baseonly) \
798
		   $(call cc-option,-fno-var-tracking)
799 800
endif

801 802 803
KBUILD_CFLAGS += $(DEBUG_CFLAGS)
export DEBUG_CFLAGS

804
ifdef CONFIG_FUNCTION_TRACER
805 806 807 808 809 810
ifdef CONFIG_FTRACE_MCOUNT_RECORD
  # gcc 5 supports generating the mcount tables directly
  ifeq ($(call cc-option-yn,-mrecord-mcount),y)
    CC_FLAGS_FTRACE	+= -mrecord-mcount
    export CC_USING_RECORD_MCOUNT := 1
  endif
811 812 813 814 815 816
  ifdef CONFIG_HAVE_NOP_MCOUNT
    ifeq ($(call cc-option-yn, -mnop-mcount),y)
      CC_FLAGS_FTRACE	+= -mnop-mcount
      CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
    endif
  endif
817
endif
818
ifdef CONFIG_HAVE_FENTRY
819 820 821 822
  ifeq ($(call cc-option-yn, -mfentry),y)
    CC_FLAGS_FTRACE	+= -mfentry
    CC_FLAGS_USING	+= -DCC_USING_FENTRY
  endif
823
endif
824 825 826
export CC_FLAGS_FTRACE
KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
827
ifdef CONFIG_DYNAMIC_FTRACE
828
	ifdef CONFIG_HAVE_C_RECORDMCOUNT
829 830 831 832
		BUILD_C_RECORDMCOUNT := y
		export BUILD_C_RECORDMCOUNT
	endif
endif
833 834
endif

835 836 837 838 839
# We trigger additional mismatches with less inlining
ifdef CONFIG_DEBUG_SECTION_MISMATCH
KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
endif

840
ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
841 842
KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
LDFLAGS_vmlinux += --gc-sections
843 844
endif

845 846 847 848
ifdef CONFIG_LIVEPATCH
KBUILD_CFLAGS += $(call cc-option, -flive-patching=inline-clone)
endif

849
# arch Makefile may override CC so keep this after arch Makefile is included
850
NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
851

Linus Torvalds's avatar
Linus Torvalds committed
852
# warn about C99 declaration after statement
853
KBUILD_CFLAGS += -Wdeclaration-after-statement
Linus Torvalds's avatar
Linus Torvalds committed
854

855
# Variable Length Arrays (VLAs) should not be used anywhere in the kernel
856
KBUILD_CFLAGS += -Wvla
857

858
# disable pointer signed / unsigned warnings in gcc 4.0
859
KBUILD_CFLAGS += -Wno-pointer-sign
Linus Torvalds's avatar
Linus Torvalds committed
860

861 862 863
# disable stringop warnings in gcc 8+
KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)

864
# disable invalid "can't wrap" optimizations for signed / pointers
865
KBUILD_CFLAGS	+= $(call cc-option,-fno-strict-overflow)
866

867 868 869 870 871 872 873 874 875
# clang sets -fmerge-all-constants by default as optimization, but this
# is non-conforming behavior for C and in fact breaks the kernel, so we
# need to disable it here generally.
KBUILD_CFLAGS	+= $(call cc-option,-fno-merge-all-constants)

# for gcc -fno-merge-all-constants disables everything, but it is fine
# to have actual conforming behavior enabled.
KBUILD_CFLAGS	+= $(call cc-option,-fmerge-constants)

876 877 878
# Make sure -fstack-check isn't enabled (like gentoo apparently did)
KBUILD_CFLAGS  += $(call cc-option,-fno-stack-check,)

879 880 881
# conserve stack if available
KBUILD_CFLAGS   += $(call cc-option,-fconserve-stack)

882 883 884
# Prohibit date/time macros, which would make the build non-deterministic
KBUILD_CFLAGS   += $(call cc-option,-Werror=date-time)

885 886 887
# enforce correct pointer usage
KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)

888 889 890
# Require designated initializers for all marked structures
KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)

891 892 893
# change __FILE__ to the relative path from the srctree
KBUILD_CFLAGS	+= $(call cc-option,-fmacro-prefix-map=$(srctree)/=)

894 895 896 897 898 899
# ensure -fcf-protection is disabled when using retpoline as it is
# incompatible with -mindirect-branch=thunk-extern
ifdef CONFIG_RETPOLINE
KBUILD_CFLAGS += $(call cc-option,-fcf-protection=none)
endif

900 901
include scripts/Makefile.kasan
include scripts/Makefile.extrawarn
902
include scripts/Makefile.ubsan
903

904 905 906 907
# Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
KBUILD_CPPFLAGS += $(KCPPFLAGS)
KBUILD_AFLAGS   += $(KAFLAGS)
KBUILD_CFLAGS   += $(KCFLAGS)
908

909 910
KBUILD_LDFLAGS_MODULE += --build-id
LDFLAGS_vmlinux += --build-id
Roland McGrath's avatar
Roland McGrath committed
911

912
ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
913
LDFLAGS_vmlinux	+= $(call ld-option, -X,)
914 915
endif

916 917 918 919
ifeq ($(CONFIG_RELR),y)
LDFLAGS_vmlinux	+= --pack-dyn-relocs=relr
endif

920 921 922
# make the checker run with the right architecture
CHECKFLAGS += --arch=$(ARCH)

923 924 925
# insure the checker run with the right endianness
CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)

926 927 928
# the checker needs the correct machine size
CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)

Linus Torvalds's avatar
Linus Torvalds committed
929
# Default kernel image to build when no specific target is given.
930
# KBUILD_IMAGE may be overruled on the command line or
Linus Torvalds's avatar
Linus Torvalds committed
931 932 933 934 935 936 937 938 939 940
# set in the environment
# Also any assignments in arch/$(ARCH)/Makefile take precedence over
# this default value
export KBUILD_IMAGE ?= vmlinux

#
# INSTALL_PATH specifies where to place the updated kernel and system map
# images. Default is /boot, but you can set it to other values
export	INSTALL_PATH ?= /boot

941 942 943 944 945 946 947
#
# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
# an argument if needed. Otherwise it defaults to the kernel install path
#
export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)

Linus Torvalds's avatar
Linus Torvalds committed
948 949 950
#
# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
# relocations required by build roots.  This is not defined in the
951
# makefile but the argument can be passed to make if needed.
Linus Torvalds's avatar
Linus Torvalds committed
952 953
#

954
MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
Linus Torvalds's avatar
Linus Torvalds committed
955 956
export MODLIB

957
#
958 959 960 961
# INSTALL_MOD_STRIP, if defined, will cause modules to be
# stripped after they are installed.  If INSTALL_MOD_STRIP is '1', then
# the default option --strip-debug will be used.  Otherwise,
# INSTALL_MOD_STRIP value will be used as the options to the strip command.
962

963 964
ifdef INSTALL_MOD_STRIP
ifeq ($(INSTALL_MOD_STRIP),1)
965
mod_strip_cmd = $(STRIP) --strip-debug
966
else
967
mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
968 969
endif # INSTALL_MOD_STRIP=1
else
970
mod_strip_cmd = true
971 972 973
endif # INSTALL_MOD_STRIP
export mod_strip_cmd

974 975 976 977 978 979 980
# CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
# after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
# or CONFIG_MODULE_COMPRESS_XZ.

mod_compress_cmd = true
ifdef CONFIG_MODULE_COMPRESS
  ifdef CONFIG_MODULE_COMPRESS_GZIP
981
    mod_compress_cmd = gzip -n -f
982 983
  endif # CONFIG_MODULE_COMPRESS_GZIP
  ifdef CONFIG_MODULE_COMPRESS_XZ
984
    mod_compress_cmd = xz -f
985 986 987 988
  endif # CONFIG_MODULE_COMPRESS_XZ
endif # CONFIG_MODULE_COMPRESS
export mod_compress_cmd

989
ifdef CONFIG_MODULE_SIG_ALL
990 991 992
$(eval $(call config_filename,MODULE_SIG_KEY))

mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
993 994 995 996 997
else
mod_sign_cmd = true
endif
export mod_sign_cmd

998 999
HOST_LIBELF_LIBS = $(shell pkg-config libelf --libs 2>/dev/null || echo -lelf)

1000 1001
ifdef CONFIG_STACK_VALIDATION
  has_libelf := $(call try-run,\
1002
		echo "int main() {}" | $(HOSTCC) -xc -o /dev/null $(HOST_LIBELF_LIBS) -,1,0)
1003 1004 1005 1006 1007 1008 1009 1010
  ifeq ($(has_libelf),1)
    objtool_target := tools/objtool FORCE
  else
    SKIP_STACK_VALIDATION := 1
    export SKIP_STACK_VALIDATION
  endif
endif

1011
PHONY += prepare0
1012

1013
export MODORDER := $(extmod-prefix)modules.order
1014

Linus Torvalds's avatar
Linus Torvalds committed
1015
ifeq ($(KBUILD_EXTMOD),)
1016
core-y		+= kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
Linus Torvalds's avatar
Linus Torvalds committed
1017 1018 1019

vmlinux-dirs	:= $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
		     $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
1020
		     $(net-y) $(net-m) $(libs-y) $(libs-m) $(virt-y)))
Linus Torvalds's avatar
Linus Torvalds committed
1021

1022 1023 1024
vmlinux-alldirs	:= $(sort $(vmlinux-dirs) Documentation \
		     $(patsubst %/,%,$(filter %/, $(init-) $(core-) \
			$(drivers-) $(net-) $(libs-) $(virt-))))
Linus Torvalds's avatar
Linus Torvalds committed
1025

1026
build-dirs	:= $(vmlinux-dirs)
1027
clean-dirs	:= $(vmlinux-alldirs)
1028

1029 1030 1031 1032
init-y		:= $(patsubst %/, %/built-in.a, $(init-y))
core-y		:= $(patsubst %/, %/built-in.a, $(core-y))
drivers-y	:= $(patsubst %/, %/built-in.a, $(drivers-y))
net-y		:= $(patsubst %/, %/built-in.a, $(net-y))
Linus Torvalds's avatar
Linus Torvalds committed
1033
libs-y1		:= $(patsubst %/, %/lib.a, $(libs-y))
1034 1035
libs-y2		:= $(patsubst %/, %/built-in.a, $(filter-out %.a, $(libs-y)))
virt-y		:= $(patsubst %/, %/built-in.a, $(virt-y))
Linus Torvalds's avatar
Linus Torvalds committed
1036

1037
# Externally visible symbols (used by link-vmlinux.sh)
1038 1039
export KBUILD_VMLINUX_OBJS := $(head-y) $(init-y) $(core-y) $(libs-y2) \
			      $(drivers-y) $(net-y) $(virt-y)
1040
export KBUILD_VMLINUX_LIBS := $(libs-y1)
1041
export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1042
export LDFLAGS_vmlinux
1043
# used by scripts/Makefile.package
1044
export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) LICENSES arch include scripts tools)
1045

1046
vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
Linus Torvalds's avatar
Linus Torvalds committed
1047

1048 1049
# Recurse until adjust_autoksyms.sh is satisfied
PHONY += autoksyms_recursive
1050
ifdef CONFIG_TRIM_UNUSED_KSYMS
1051
autoksyms_recursive: descend modules.order
1052
	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1053
	  "$(MAKE) -f $(srctree)/Makefile vmlinux"
1054
endif
1055

1056 1057 1058 1059 1060 1061 1062
# For the kernel to actually contain only the needed exported symbols,
# we have to build modules as well to determine what those symbols are.
# (this can be evaluated only once include/config/auto.conf has been included)
ifdef CONFIG_TRIM_UNUSED_KSYMS
  KBUILD_MODULES := 1
endif

1063 1064 1065 1066 1067
autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)

$(autoksyms_h):
	$(Q)mkdir -p $(dir $@)
	$(Q)touch $@
1068

1069 1070 1071
ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)

# Final link of vmlinux with optional arch pass after final link
1072
cmd_link-vmlinux =                                                 \
1073
	$(CONFIG_SHELL) $< $(LD) $(KBUILD_LDFLAGS) $(LDFLAGS_vmlinux) ;    \
1074
	$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1075

1076
vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1077
	+$(call if_changed,link-vmlinux)
1078

1079 1080
targets := vmlinux

1081
# The actual objects are generated when descending,
Linus Torvalds's avatar
Linus Torvalds committed
1082
# make sure no implicit rule kicks in
1083
$(sort $(vmlinux-deps)): descend ;
Linus Torvalds's avatar
Linus Torvalds committed
1084

1085
filechk_kernel.release = \
1086 1087
	echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"

1088
# Store (new) KERNELRELEASE string in include/config/kernel.release
1089
include/config/kernel.release: FORCE
1090
	$(call filechk,kernel.release)
1091

1092 1093 1094 1095
# Additional helpers built in scripts/
# Carefully list dependencies so we do not try to build scripts twice
# in parallel
PHONY += scripts
1096
scripts: scripts_basic scripts_dtc
1097
	$(Q)$(MAKE) $(build)=$(@)
1098

Linus Torvalds's avatar
Linus Torvalds committed
1099
# Things we need to do before we recursively start building the kernel
1100 1101 1102 1103
# or the modules are listed in "prepare".
# A multi level approach is used. prepareN is processed before prepareN-1.
# archprepare is used in arch Makefiles and when processed asm symlink,
# version.h and scripts_basic is processed / created.
Linus Torvalds's avatar
Linus Torvalds committed
1104

1105
PHONY += prepare archprepare
1106

1107
archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1108
	asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h
1109

1110
prepare0: archprepare
1111
	$(Q)$(MAKE) $(build)=scripts/mod
1112
	$(Q)$(MAKE) $(build)=.
1113

Linus Torvalds's avatar
Linus Torvalds committed
1114
# All the preparing..
1115 1116
prepare: prepare0 prepare-objtool

1117
# Support for using generic headers in asm-generic
1118 1119
asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj

1120 1121
PHONY += asm-generic uapi-asm-generic
asm-generic: uapi-asm-generic
1122 1123
	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
	generic=include/asm-generic