Makefile 58.2 KB
Newer Older
Linus Torvalds's avatar
Linus Torvalds committed
1
VERSION = 4
Linus Torvalds's avatar
Linus Torvalds committed
2
PATCHLEVEL = 14
Linus Torvalds's avatar
Linus Torvalds committed
3
SUBLEVEL = 0
Linus Torvalds's avatar
Linus Torvalds committed
4
EXTRAVERSION = -rc3
Linus Torvalds's avatar
Linus Torvalds committed
5
NAME = Fearless Coyote
Linus Torvalds's avatar
Linus Torvalds committed
6 7 8 9 10 11 12

# *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.

13 14 15 16
# o Do not use make's built-in rules and variables
#   (this increases performance and avoids hard-to-debug behaviour);
# o Look for make include files relative to root of kernel src
MAKEFLAGS += -rR --include-dir=$(CURDIR)
Linus Torvalds's avatar
Linus Torvalds committed
17

18
# Avoid funny character set dependencies
19
unexport LC_ALL
20 21
LC_COLLATE=C
LC_NUMERIC=C
22
export LC_COLLATE LC_NUMERIC
23

24 25 26
# Avoid interference with shell env settings
unexport GREP_OPTIONS

Linus Torvalds's avatar
Linus Torvalds committed
27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42
# 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
# unavoidable when linking the built-in.o targets which finally
# 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.

43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
# 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
66 67 68
# To put more focus on warnings, be less verbose as default
# Use 'make V=1' to see the full commands

69 70
ifeq ("$(origin V)", "command line")
  KBUILD_VERBOSE = $(V)
Linus Torvalds's avatar
Linus Torvalds committed
71 72 73 74 75
endif
ifndef KBUILD_VERBOSE
  KBUILD_VERBOSE = 0
endif

76 77 78 79 80 81 82 83 84 85 86
ifeq ($(KBUILD_VERBOSE),1)
  quiet =
  Q =
else
  quiet=quiet_
  Q = @
endif

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

87
ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
88
  quiet=silent_
89
  tools_silent=s
90 91 92 93
endif

export quiet Q KBUILD_VERBOSE

Linus Torvalds's avatar
Linus Torvalds committed
94 95 96 97 98
# kbuild supports saving output files in a separate directory.
# To locate output files in a separate directory two syntaxes are supported.
# In both cases the working directory must be the root of the kernel src.
# 1) O=
# Use "make O=dir/to/store/output/files/"
99
#
Linus Torvalds's avatar
Linus Torvalds committed
100 101 102 103 104 105 106 107 108
# 2) Set KBUILD_OUTPUT
# Set the environment variable KBUILD_OUTPUT to point to the directory
# where the output files shall be placed.
# export KBUILD_OUTPUT=dir/to/store/output/files/
# make
#
# The O= assignment takes precedence over the KBUILD_OUTPUT environment
# variable.

109 110
# KBUILD_SRC is not intended to be used by the regular user (for now),
# it is set on invocation of make with KBUILD_OUTPUT or O= specified.
Linus Torvalds's avatar
Linus Torvalds committed
111 112 113 114
ifeq ($(KBUILD_SRC),)

# OK, Make called in directory where kernel src resides
# Do we want to locate output files in a separate directory?
115 116
ifeq ("$(origin O)", "command line")
  KBUILD_OUTPUT := $(O)
Linus Torvalds's avatar
Linus Torvalds committed
117 118 119
endif

# That's our default target when none is given on the command line
120
PHONY := _all
Linus Torvalds's avatar
Linus Torvalds committed
121 122
_all:

123 124 125
# Cancel implicit rules on top Makefile
$(CURDIR)/Makefile Makefile: ;

126 127 128 129
ifneq ($(words $(subst :, ,$(CURDIR))), 1)
  $(error main directory cannot contain spaces nor colons)
endif

Linus Torvalds's avatar
Linus Torvalds committed
130 131 132
ifneq ($(KBUILD_OUTPUT),)
# check that the output directory actually exists
saved-output := $(KBUILD_OUTPUT)
133 134
$(shell [ -d $(KBUILD_OUTPUT) ] || mkdir -p $(KBUILD_OUTPUT))
KBUILD_OUTPUT := $(realpath $(KBUILD_OUTPUT))
Linus Torvalds's avatar
Linus Torvalds committed
135
$(if $(KBUILD_OUTPUT),, \
136
     $(error failed to create output directory "$(saved-output)"))
Linus Torvalds's avatar
Linus Torvalds committed
137

138 139
PHONY += $(MAKECMDGOALS) sub-make

140
$(filter-out _all sub-make $(CURDIR)/Makefile, $(MAKECMDGOALS)) _all: sub-make
141
	@:
142

143
# Invoke a second make in the output directory, passing relevant variables
144
sub-make:
145
	$(Q)$(MAKE) -C $(KBUILD_OUTPUT) KBUILD_SRC=$(CURDIR) \
146
	-f $(CURDIR)/Makefile $(filter-out _all sub-make,$(MAKECMDGOALS))
Linus Torvalds's avatar
Linus Torvalds committed
147 148 149 150 151 152 153 154 155

# Leave processing to above invocation of make
skip-makefile := 1
endif # ifneq ($(KBUILD_OUTPUT),)
endif # ifeq ($(KBUILD_SRC),)

# We process the rest of the Makefile if this is the final invocation of make
ifeq ($(skip-makefile),)

156 157 158 159 160
# 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

161 162 163 164 165 166 167
# 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
168 169
# See the file "Documentation/dev-tools/sparse.rst" for more details,
# including where to get the "sparse" utility.
170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188

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

# Use make M=dir to specify directory of external module to build
# Old syntax make ... SUBDIRS=$PWD is still supported
# Setting the environment variable KBUILD_EXTMOD take precedence
ifdef SUBDIRS
  KBUILD_EXTMOD ?= $(SUBDIRS)
endif

ifeq ("$(origin M)", "command line")
  KBUILD_EXTMOD := $(M)
endif

Linus Torvalds's avatar
Linus Torvalds committed
189 190
# If building an external module we do not care about the all: rule
# but instead _all depend on modules
191
PHONY += all
Linus Torvalds's avatar
Linus Torvalds committed
192 193 194 195 196 197
ifeq ($(KBUILD_EXTMOD),)
_all: all
else
_all: modules
endif

198 199 200 201 202 203 204 205 206 207 208
ifeq ($(KBUILD_SRC),)
        # building in the source tree
        srctree := .
else
        ifeq ($(KBUILD_SRC)/,$(dir $(CURDIR)))
                # building in a subdirectory of the source tree
                srctree := ..
        else
                srctree := $(KBUILD_SRC)
        endif
endif
209
objtree		:= .
Linus Torvalds's avatar
Linus Torvalds committed
210 211 212
src		:= $(srctree)
obj		:= $(objtree)

213
VPATH		:= $(srctree)$(if $(KBUILD_EXTMOD),:$(KBUILD_EXTMOD))
Linus Torvalds's avatar
Linus Torvalds committed
214

215
export srctree objtree VPATH
Linus Torvalds's avatar
Linus Torvalds committed
216 217 218 219

# SUBARCH tells the usermode build what the underlying arch is.  That is set
# first, and if a usermode build is happening, the "ARCH=um" on the command
# line overrides the setting of ARCH below.  If a native build is happening,
220
# then ARCH is assigned, getting whatever value it gets normally, and
Linus Torvalds's avatar
Linus Torvalds committed
221 222
# SUBARCH is subsequently ignored.

223 224
SUBARCH := $(shell uname -m | sed -e s/i.86/x86/ -e s/x86_64/x86/ \
				  -e s/sun4u/sparc64/ \
Linus Torvalds's avatar
Linus Torvalds committed
225
				  -e s/arm.*/arm/ -e s/sa110/arm/ \
226
				  -e s/s390x/s390/ -e s/parisc64/parisc/ \
Paul Mundt's avatar
Paul Mundt committed
227
				  -e s/ppc.*/powerpc/ -e s/mips.*/mips/ \
228
				  -e s/sh[234].*/sh/ -e s/aarch64.*/arm64/ )
Linus Torvalds's avatar
Linus Torvalds committed
229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245

# 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.
246 247
# A third alternative is to store a setting in .config so that plain
# "make" in the configured kernel build directory always uses that.
Linus Torvalds's avatar
Linus Torvalds committed
248 249
# Default value for CROSS_COMPILE is not to prefix executables
# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
250
ARCH		?= $(SUBARCH)
251
CROSS_COMPILE	?= $(CONFIG_CROSS_COMPILE:"%"=%)
Linus Torvalds's avatar
Linus Torvalds committed
252 253

# Architecture as present in compile.h
254 255
UTS_MACHINE 	:= $(ARCH)
SRCARCH 	:= $(ARCH)
Linus Torvalds's avatar
Linus Torvalds committed
256

257 258 259 260 261 262 263
# Additional ARCH settings for x86
ifeq ($(ARCH),i386)
        SRCARCH := x86
endif
ifeq ($(ARCH),x86_64)
        SRCARCH := x86
endif
264

Sam Ravnborg's avatar
Sam Ravnborg committed
265
# Additional ARCH settings for sparc
266 267 268
ifeq ($(ARCH),sparc32)
       SRCARCH := sparc
endif
269
ifeq ($(ARCH),sparc64)
Sam Ravnborg's avatar
Sam Ravnborg committed
270
       SRCARCH := sparc
271
endif
272

273 274 275 276 277
# Additional ARCH settings for sh
ifeq ($(ARCH),sh64)
       SRCARCH := sh
endif

278
# Additional ARCH settings for tile
279 280 281
ifeq ($(ARCH),tilepro)
       SRCARCH := tile
endif
282 283 284 285
ifeq ($(ARCH),tilegx)
       SRCARCH := tile
endif

Sam Ravnborg's avatar
Sam Ravnborg committed
286 287 288
# Where to locate arch specific headers
hdr-arch  := $(SRCARCH)

289
KCONFIG_CONFIG	?= .config
290
export KCONFIG_CONFIG
291

Linus Torvalds's avatar
Linus Torvalds committed
292 293 294 295 296
# SHELL used by kbuild
CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
	  else if [ -x /bin/bash ]; then echo /bin/bash; \
	  else echo sh; fi ; fi)

297 298 299 300
HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS)
HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS)
HOST_LFS_LIBS := $(shell getconf LFS_LIBS)

301 302
HOSTCC       = gcc
HOSTCXX      = g++
303 304 305 306 307
HOSTCFLAGS   := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 \
		-fomit-frame-pointer -std=gnu89 $(HOST_LFS_CFLAGS)
HOSTCXXFLAGS := -O2 $(HOST_LFS_CFLAGS)
HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS)
HOST_LOADLIBES := $(HOST_LFS_LIBS)
Linus Torvalds's avatar
Linus Torvalds committed
308

309 310 311 312 313
ifeq ($(shell $(HOSTCC) -v 2>&1 | grep -c "clang version"), 1)
HOSTCFLAGS  += -Wno-unused-value -Wno-unused-parameter \
		-Wno-missing-field-initializers -fno-delete-null-pointer-checks
endif

314 315
# Decide whether to build built-in, modular, or both.
# Normally, just do built-in.
Linus Torvalds's avatar
Linus Torvalds committed
316 317 318 319

KBUILD_MODULES :=
KBUILD_BUILTIN := 1

320 321 322 323
# 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.
Linus Torvalds's avatar
Linus Torvalds committed
324 325 326 327 328

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

329 330 331
# 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
Linus Torvalds's avatar
Linus Torvalds committed
332 333 334 335 336 337 338 339 340

ifneq ($(filter all _all modules,$(MAKECMDGOALS)),)
  KBUILD_MODULES := 1
endif

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

341
export KBUILD_MODULES KBUILD_BUILTIN
Linus Torvalds's avatar
Linus Torvalds committed
342 343
export KBUILD_CHECKSRC KBUILD_SRC KBUILD_EXTMOD

344
# We need some generic definitions (do not try to remake the file).
345 346
scripts/Kbuild.include: ;
include scripts/Kbuild.include
Linus Torvalds's avatar
Linus Torvalds committed
347 348 349 350 351 352 353 354 355 356 357 358 359

# 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
AWK		= awk
GENKSYMS	= scripts/genksyms/genksyms
360
INSTALLKERNEL  := installkernel
Linus Torvalds's avatar
Linus Torvalds committed
361 362
DEPMOD		= /sbin/depmod
PERL		= perl
363
PYTHON		= python
Linus Torvalds's avatar
Linus Torvalds committed
364 365
CHECK		= sparse

366 367
CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
		  -Wbitwise -Wno-return-void $(CF)
368
NOSTDINC_FLAGS  =
369 370 371
CFLAGS_MODULE   =
AFLAGS_MODULE   =
LDFLAGS_MODULE  =
Linus Torvalds's avatar
Linus Torvalds committed
372 373
CFLAGS_KERNEL	=
AFLAGS_KERNEL	=
374
LDFLAGS_vmlinux =
375
CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage -fno-tree-loop-im $(call cc-disable-warning,maybe-uninitialized,)
Emese Revfy's avatar
Emese Revfy committed
376
CFLAGS_KCOV	:= $(call cc-option,-fsanitize-coverage=trace-pc,)
Linus Torvalds's avatar
Linus Torvalds committed
377 378


379 380 381
# Use USERINCLUDE when you must reference the UAPI directories only.
USERINCLUDE    := \
		-I$(srctree)/arch/$(hdr-arch)/include/uapi \
382
		-I$(objtree)/arch/$(hdr-arch)/include/generated/uapi \
383
		-I$(srctree)/include/uapi \
384
		-I$(objtree)/include/generated/uapi \
385 386
                -include $(srctree)/include/linux/kconfig.h

Linus Torvalds's avatar
Linus Torvalds committed
387 388
# Use LINUXINCLUDE when you must reference the include/ directory.
# Needed to be compatible with the O= option
389 390
LINUXINCLUDE    := \
		-I$(srctree)/arch/$(hdr-arch)/include \
391
		-I$(objtree)/arch/$(hdr-arch)/include/generated \
392
		$(if $(KBUILD_SRC), -I$(srctree)/include) \
393 394
		-I$(objtree)/include \
		$(USERINCLUDE)
Linus Torvalds's avatar
Linus Torvalds committed
395

396
KBUILD_CPPFLAGS := -D__KERNEL__
Linus Torvalds's avatar
Linus Torvalds committed
397

398
KBUILD_CFLAGS   := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
399
		   -fno-strict-aliasing -fno-common -fshort-wchar \
400
		   -Werror-implicit-function-declaration \
401
		   -Wno-format-security \
402 403
		   -std=gnu89 $(call cc-option,-fno-PIE)

404

405 406
KBUILD_AFLAGS_KERNEL :=
KBUILD_CFLAGS_KERNEL :=
407
KBUILD_AFLAGS   := -D__ASSEMBLY__ $(call cc-option,-fno-PIE)
408 409 410
KBUILD_AFLAGS_MODULE  := -DMODULE
KBUILD_CFLAGS_MODULE  := -DMODULE
KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
Linus Torvalds's avatar
Linus Torvalds committed
411

Roman Zippel's avatar
Roman Zippel committed
412 413
# Read KERNELRELEASE from include/config/kernel.release (if it exists)
KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
414
KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
415

416
export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
417
export ARCH SRCARCH CONFIG_SHELL HOSTCC HOSTCFLAGS CROSS_COMPILE AS LD CC
418
export CPP AR NM STRIP OBJCOPY OBJDUMP HOSTLDFLAGS HOST_LOADLIBES
419
export MAKE AWK GENKSYMS INSTALLKERNEL PERL PYTHON UTS_MACHINE
420
export HOSTCXX HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
Linus Torvalds's avatar
Linus Torvalds committed
421

422
export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS LDFLAGS
423
export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE CFLAGS_GCOV CFLAGS_KCOV CFLAGS_KASAN CFLAGS_UBSAN
424
export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
425
export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
426
export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
427
export KBUILD_ARFLAGS
Linus Torvalds's avatar
Linus Torvalds committed
428 429 430 431 432 433 434 435

# When compiling out-of-tree modules, put MODVERDIR in the module
# tree rather than in the kernel tree. The kernel tree might
# even be read-only.
export MODVERDIR := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_versions

# Files to ignore in find ... statements

436 437 438
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
439 440
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
441 442 443 444

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

445
# Basic helpers built in scripts/basic/
446
PHONY += scripts_basic
Linus Torvalds's avatar
Linus Torvalds committed
447 448
scripts_basic:
	$(Q)$(MAKE) $(build)=scripts/basic
449
	$(Q)rm -f .tmp_quiet_recordmcount
Linus Torvalds's avatar
Linus Torvalds committed
450

451 452 453
# To avoid any implicit rule to kick in, define an empty command.
scripts/basic/%: scripts_basic ;

454
PHONY += outputmakefile
455 456 457
# outputmakefile generates a Makefile in the output directory, if using a
# separate output directory. This allows convenient use of make in the
# output directory.
Linus Torvalds's avatar
Linus Torvalds committed
458
outputmakefile:
459
ifneq ($(KBUILD_SRC),)
460
	$(Q)ln -fsn $(srctree) source
461 462 463
	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile \
	    $(srctree) $(objtree) $(VERSION) $(PATCHLEVEL)
endif
Linus Torvalds's avatar
Linus Torvalds committed
464

Sam Ravnborg's avatar
Sam Ravnborg committed
465
# Support for using generic headers in asm-generic
466 467
PHONY += asm-generic uapi-asm-generic
asm-generic: uapi-asm-generic
Sam Ravnborg's avatar
Sam Ravnborg committed
468
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
469
	            src=asm obj=arch/$(SRCARCH)/include/generated/asm
470
uapi-asm-generic:
471 472
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
	            src=uapi/asm obj=arch/$(SRCARCH)/include/generated/uapi/asm
Sam Ravnborg's avatar
Sam Ravnborg committed
473

Linus Torvalds's avatar
Linus Torvalds committed
474 475 476 477
# 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.
478
# For example 'make oldconfig all'.
Linus Torvalds's avatar
Linus Torvalds committed
479 480 481
# Detect when mixed targets is specified, and make a second invocation
# of make so .config is not included in this case either (for *config).

482
version_h := include/generated/uapi/linux/version.h
483
old_version_h := include/linux/version.h
David Howells's avatar
David Howells committed
484

485
no-dot-config-targets := clean mrproper distclean \
486
			 cscope gtags TAGS tags help% %docs check% coccicheck \
David Howells's avatar
David Howells committed
487
			 $(version_h) headers_% archheaders archscripts \
488
			 kernelversion %src-pkg
Linus Torvalds's avatar
Linus Torvalds committed
489 490 491 492 493 494 495 496 497 498 499 500 501 502

config-targets := 0
mixed-targets  := 0
dot-config     := 1

ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
	ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
		dot-config := 0
	endif
endif

ifeq ($(KBUILD_EXTMOD),)
        ifneq ($(filter config %config,$(MAKECMDGOALS)),)
                config-targets := 1
503
                ifneq ($(words $(MAKECMDGOALS)),1)
Linus Torvalds's avatar
Linus Torvalds committed
504 505 506 507
                        mixed-targets := 1
                endif
        endif
endif
508
# install and modules_install need also be processed one by one
509 510 511 512 513
ifneq ($(filter install,$(MAKECMDGOALS)),)
        ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
	        mixed-targets := 1
        endif
endif
Linus Torvalds's avatar
Linus Torvalds committed
514 515 516 517 518 519

ifeq ($(mixed-targets),1)
# ===========================================================================
# We're called with mixed targets (*config and build targets).
# Handle them one by one.

520 521 522 523 524 525 526 527 528 529
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
Linus Torvalds's avatar
Linus Torvalds committed
530 531 532 533 534 535 536 537 538 539

else
ifeq ($(config-targets),1)
# ===========================================================================
# *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'
540
include arch/$(SRCARCH)/Makefile
541
export KBUILD_DEFCONFIG KBUILD_KCONFIG
Linus Torvalds's avatar
Linus Torvalds committed
542

543 544 545 546
config: scripts_basic outputmakefile FORCE
	$(Q)$(MAKE) $(build)=scripts/kconfig $@

%config: scripts_basic outputmakefile FORCE
Linus Torvalds's avatar
Linus Torvalds committed
547 548 549 550 551 552 553 554 555 556
	$(Q)$(MAKE) $(build)=scripts/kconfig $@

else
# ===========================================================================
# Build targets only - this includes vmlinux, arch specific targets, clean
# targets and others. In general all targets except *config targets.

ifeq ($(KBUILD_EXTMOD),)
# Additional helpers built in scripts/
# Carefully list dependencies so we do not try to build scripts twice
557
# in parallel
558
PHONY += scripts
559
scripts: scripts_basic include/config/auto.conf include/config/tristate.conf \
Emese Revfy's avatar
Emese Revfy committed
560
	 asm-generic gcc-plugins
Linus Torvalds's avatar
Linus Torvalds committed
561 562 563 564
	$(Q)$(MAKE) $(build)=$(@)

# Objects we will link into vmlinux / subdirs we need to visit
init-y		:= init/
565
drivers-y	:= drivers/ sound/ firmware/
Linus Torvalds's avatar
Linus Torvalds committed
566 567 568
net-y		:= net/
libs-y		:= lib/
core-y		:= usr/
569
virt-y		:= virt/
Linus Torvalds's avatar
Linus Torvalds committed
570 571 572
endif # KBUILD_EXTMOD

ifeq ($(dot-config),1)
573 574
# Read in config
-include include/config/auto.conf
Linus Torvalds's avatar
Linus Torvalds committed
575

576
ifeq ($(KBUILD_EXTMOD),)
Linus Torvalds's avatar
Linus Torvalds committed
577 578
# Read in dependencies to all Kconfig* files, make sure to run
# oldconfig if changes are detected.
579
-include include/config/auto.conf.cmd
Linus Torvalds's avatar
Linus Torvalds committed
580 581

# To avoid any implicit rule to kick in, define an empty command
582
$(KCONFIG_CONFIG) include/config/auto.conf.cmd: ;
Linus Torvalds's avatar
Linus Torvalds committed
583

584
# If .config is newer than include/config/auto.conf, someone tinkered
585
# with it and forgot to run make oldconfig.
586
# if auto.conf.cmd is missing then we are probably in a cleaned tree so
587
# we execute the config step to be sure to catch updated Kconfig files
588
include/config/%.conf: $(KCONFIG_CONFIG) include/config/auto.conf.cmd
Linus Torvalds's avatar
Linus Torvalds committed
589
	$(Q)$(MAKE) -f $(srctree)/Makefile silentoldconfig
590
else
591
# external modules needs include/generated/autoconf.h and include/config/auto.conf
592 593 594 595
# but do not care if they are up-to-date. Use auto.conf to trigger the test
PHONY += include/config/auto.conf

include/config/auto.conf:
596
	$(Q)test -e include/generated/autoconf.h -a -e $@ || (		\
597 598 599 600 601
	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 ;							\
602 603 604
	/bin/false)

endif # KBUILD_EXTMOD
605

Linus Torvalds's avatar
Linus Torvalds committed
606 607
else
# Dummy target needed, because used as prerequisite
608
include/config/auto.conf: ;
609
endif # $(dot-config)
Linus Torvalds's avatar
Linus Torvalds committed
610

611 612 613 614 615 616 617
# 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

Linus Torvalds's avatar
Linus Torvalds committed
618 619 620
# 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
Michal Marek's avatar
Michal Marek committed
621
# Defaults to vmlinux, but the arch makefile usually adds further targets
Linus Torvalds's avatar
Linus Torvalds committed
622 623
all: vmlinux

624 625 626 627 628
# The arch Makefile can set ARCH_{CPP,A,C}FLAGS to override the default
# values of the respective KBUILD_* variables
ARCH_CPPFLAGS :=
ARCH_AFLAGS :=
ARCH_CFLAGS :=
629
include arch/$(SRCARCH)/Makefile
630 631

KBUILD_CFLAGS	+= $(call cc-option,-fno-delete-null-pointer-checks,)
632
KBUILD_CFLAGS	+= $(call cc-disable-warning,frame-address,)
633 634 635
KBUILD_CFLAGS	+= $(call cc-disable-warning, format-truncation)
KBUILD_CFLAGS	+= $(call cc-disable-warning, format-overflow)
KBUILD_CFLAGS	+= $(call cc-disable-warning, int-in-bool-context)
636

Linus Torvalds's avatar
Linus Torvalds committed
637
ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
638 639
KBUILD_CFLAGS	+= $(call cc-option,-Oz,-Os)
KBUILD_CFLAGS	+= $(call cc-disable-warning,maybe-uninitialized,)
Linus Torvalds's avatar
Linus Torvalds committed
640
else
641
ifdef CONFIG_PROFILE_ALL_BRANCHES
642
KBUILD_CFLAGS	+= -O2 $(call cc-disable-warning,maybe-uninitialized,)
643 644 645
else
KBUILD_CFLAGS   += -O2
endif
Linus Torvalds's avatar
Linus Torvalds committed
646 647
endif

648 649 650
KBUILD_CFLAGS += $(call cc-ifversion, -lt, 0409, \
			$(call cc-disable-warning,maybe-uninitialized,))

651 652 653
# Tell gcc to never replace conditional load with a non-conditional one
KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)

654 655 656 657 658 659
# check for 'asm goto'
ifeq ($(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC) $(KBUILD_CFLAGS)), y)
	KBUILD_CFLAGS += -DCC_HAVE_ASM_GOTO
	KBUILD_AFLAGS += -DCC_HAVE_ASM_GOTO
endif

Emese Revfy's avatar
Emese Revfy committed
660 661
include scripts/Makefile.gcc-plugins

Andi Kleen's avatar
Andi Kleen committed
662 663 664 665 666 667 668 669 670 671
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

672
ifneq ($(CONFIG_FRAME_WARN),0)
673 674 675
KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
endif

676 677 678
# This selects the stack protector compiler flag. Testing it is delayed
# until after .config has been reprocessed, in the prepare-compiler-check
# target.
679
ifdef CONFIG_CC_STACKPROTECTOR_REGULAR
680
  stackp-flag := -fstack-protector
681
  stackp-name := REGULAR
682 683
else
ifdef CONFIG_CC_STACKPROTECTOR_STRONG
684
  stackp-flag := -fstack-protector-strong
685
  stackp-name := STRONG
686 687 688
else
  # Force off for distro compilers that enable stack protector by default.
  stackp-flag := $(call cc-option, -fno-stack-protector)
689
endif
690
endif
691 692
# Find arch-specific stack protector compiler sanity-checking script.
ifdef CONFIG_CC_STACKPROTECTOR
693 694
  stackp-path := $(srctree)/scripts/gcc-$(SRCARCH)_$(BITS)-has-stack-protector.sh
  stackp-check := $(wildcard $(stackp-path))
695
endif
696
KBUILD_CFLAGS += $(stackp-flag)
697

Michal Marek's avatar
Michal Marek committed
698
ifeq ($(cc-name),clang)
699 700 701 702 703 704 705 706 707
ifneq ($(CROSS_COMPILE),)
CLANG_TARGET	:= -target $(notdir $(CROSS_COMPILE:%-=%))
GCC_TOOLCHAIN	:= $(realpath $(dir $(shell which $(LD)))/..)
endif
ifneq ($(GCC_TOOLCHAIN),)
CLANG_GCC_TC	:= -gcc-toolchain $(GCC_TOOLCHAIN)
endif
KBUILD_CFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC)
KBUILD_AFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC)
708 709 710 711
KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
KBUILD_CFLAGS += $(call cc-disable-warning, unused-variable)
KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier)
KBUILD_CFLAGS += $(call cc-disable-warning, gnu)
712
KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
713 714 715 716 717 718
# Quiet clang warning: comparison of unsigned expression < 0 is always false
KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare)
# 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
KBUILD_CFLAGS += $(call cc-option, -mno-global-merge,)
719
KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior)
720 721
KBUILD_CFLAGS += $(call cc-option, -no-integrated-as)
KBUILD_AFLAGS += $(call cc-option, -no-integrated-as)
722 723
else

724
# These warnings generated too much noise in a regular build.
725
# Use make W=1 to enable them (see scripts/Makefile.extrawarn)
726
KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
727
KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
728
endif
729

Linus Torvalds's avatar
Linus Torvalds committed
730
ifdef CONFIG_FRAME_POINTER
731
KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
Linus Torvalds's avatar
Linus Torvalds committed
732
else
733 734 735 736 737 738
# 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
739
KBUILD_CFLAGS	+= -fomit-frame-pointer
Linus Torvalds's avatar
Linus Torvalds committed
740
endif
741
endif
Linus Torvalds's avatar
Linus Torvalds committed
742

743 744
KBUILD_CFLAGS   += $(call cc-option, -fno-var-tracking-assignments)

Linus Torvalds's avatar
Linus Torvalds committed
745
ifdef CONFIG_DEBUG_INFO
746 747 748
ifdef CONFIG_DEBUG_INFO_SPLIT
KBUILD_CFLAGS   += $(call cc-option, -gsplit-dwarf, -g)
else
749
KBUILD_CFLAGS	+= -g
750
endif
751
KBUILD_AFLAGS	+= -Wa,-gdwarf-2
Linus Torvalds's avatar
Linus Torvalds committed
752
endif
753 754 755
ifdef CONFIG_DEBUG_INFO_DWARF4
KBUILD_CFLAGS	+= $(call cc-option, -gdwarf-4,)
endif
Linus Torvalds's avatar
Linus Torvalds committed
756

757
ifdef CONFIG_DEBUG_INFO_REDUCED
758 759
KBUILD_CFLAGS 	+= $(call cc-option, -femit-struct-debug-baseonly) \
		   $(call cc-option,-fno-var-tracking)
760 761
endif

762
ifdef CONFIG_FUNCTION_TRACER
763 764 765 766
ifndef CC_FLAGS_FTRACE
CC_FLAGS_FTRACE := -pg
endif
export CC_FLAGS_FTRACE
767 768 769
ifdef CONFIG_HAVE_FENTRY
CC_USING_FENTRY	:= $(call cc-option, -mfentry -DCC_USING_FENTRY)
endif
770
KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_USING_FENTRY)
771
KBUILD_AFLAGS	+= $(CC_USING_FENTRY)
772
ifdef CONFIG_DYNAMIC_FTRACE
773
	ifdef CONFIG_HAVE_C_RECORDMCOUNT
774 775 776 777
		BUILD_C_RECORDMCOUNT := y
		export BUILD_C_RECORDMCOUNT
	endif
endif
778 779
endif

780 781 782 783 784
# We trigger additional mismatches with less inlining
ifdef CONFIG_DEBUG_SECTION_MISMATCH
KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
endif

785 786 787 788 789
ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
KBUILD_CFLAGS	+= $(call cc-option,-ffunction-sections,)
KBUILD_CFLAGS	+= $(call cc-option,-fdata-sections,)
endif

790
# arch Makefile may override CC so keep this after arch Makefile is included
791
NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
792 793
CHECKFLAGS     += $(NOSTDINC_FLAGS)

Linus Torvalds's avatar
Linus Torvalds committed
794
# warn about C99 declaration after statement
795
KBUILD_CFLAGS += $(call cc-option,-Wdeclaration-after-statement,)
Linus Torvalds's avatar
Linus Torvalds committed
796

797
# disable pointer signed / unsigned warnings in gcc 4.0
798
KBUILD_CFLAGS += $(call cc-disable-warning, pointer-sign)
Linus Torvalds's avatar
Linus Torvalds committed
799

800
# disable invalid "can't wrap" optimizations for signed / pointers
801
KBUILD_CFLAGS	+= $(call cc-option,-fno-strict-overflow)
802

803 804 805
# conserve stack if available
KBUILD_CFLAGS   += $(call cc-option,-fconserve-stack)

806 807 808 809 810 811
# disallow errors like 'EXPORT_GPL(foo);' with missing header
KBUILD_CFLAGS   += $(call cc-option,-Werror=implicit-int)

# require functions to have arguments in prototypes, not empty 'int foo()'
KBUILD_CFLAGS   += $(call cc-option,-Werror=strict-prototypes)

812 813 814
# Prohibit date/time macros, which would make the build non-deterministic
KBUILD_CFLAGS   += $(call cc-option,-Werror=date-time)

815 816 817
# enforce correct pointer usage
KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)

818 819 820
# Require designated initializers for all marked structures
KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)

821 822 823
# use the deterministic mode of AR if available
KBUILD_ARFLAGS := $(call ar-option,D)

824 825
include scripts/Makefile.kasan
include scripts/Makefile.extrawarn
826
include scripts/Makefile.ubsan
827

828 829 830 831 832
# Add any arch overrides and user supplied CPPFLAGS, AFLAGS and CFLAGS as the
# last assignments
KBUILD_CPPFLAGS += $(ARCH_CPPFLAGS) $(KCPPFLAGS)
KBUILD_AFLAGS   += $(ARCH_AFLAGS)   $(KAFLAGS)
KBUILD_CFLAGS   += $(ARCH_CFLAGS)   $(KCFLAGS)
833

Roland McGrath's avatar
Roland McGrath committed
834
# Use --build-id when available.
835
LDFLAGS_BUILD_ID := $(patsubst -Wl$(comma)%,%,\
836
			      $(call cc-ldoption, -Wl$(comma)--build-id,))
837
KBUILD_LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID)
Roland McGrath's avatar
Roland McGrath committed
838 839
LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)

840 841 842 843
ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
LDFLAGS_vmlinux	+= $(call ld-option, --gc-sections,)
endif

844
ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
845
LDFLAGS_vmlinux	+= $(call ld-option, -X,)
846 847
endif

Linus Torvalds's avatar
Linus Torvalds committed
848
# Default kernel image to build when no specific target is given.
849
# KBUILD_IMAGE may be overruled on the command line or
Linus Torvalds's avatar
Linus Torvalds committed
850 851 852 853 854 855 856 857 858 859
# 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

860 861 862 863 864 865 866
#
# 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
867 868 869
#
# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
# relocations required by build roots.  This is not defined in the
870
# makefile but the argument can be passed to make if needed.
Linus Torvalds's avatar
Linus Torvalds committed
871 872
#

873
MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
Linus Torvalds's avatar
Linus Torvalds committed
874 875
export MODLIB

876
#
877 878 879 880
# 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.
881

882 883
ifdef INSTALL_MOD_STRIP
ifeq ($(INSTALL_MOD_STRIP),1)
884
mod_strip_cmd = $(STRIP) --strip-debug
885
else
886
mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
887 888
endif # INSTALL_MOD_STRIP=1
else
889
mod_strip_cmd = true
890 891 892
endif # INSTALL_MOD_STRIP
export mod_strip_cmd

893 894 895 896 897 898 899
# 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
900
    mod_compress_cmd = gzip -n -f
901 902
  endif # CONFIG_MODULE_COMPRESS_GZIP
  ifdef CONFIG_MODULE_COMPRESS_XZ
903
    mod_compress_cmd = xz -f
904 905 906 907
  endif # CONFIG_MODULE_COMPRESS_XZ
endif # CONFIG_MODULE_COMPRESS
export mod_compress_cmd

908 909 910
# Select initial ramdisk compression format, default is gzip(1).
# This shall be used by the dracut(8) tool while creating an initramfs image.
#
Jan Beulich's avatar
Jan Beulich committed
911 912 913 914 915 916
INITRD_COMPRESS-y                  := gzip
INITRD_COMPRESS-$(CONFIG_RD_BZIP2) := bzip2
INITRD_COMPRESS-$(CONFIG_RD_LZMA)  := lzma
INITRD_COMPRESS-$(CONFIG_RD_XZ)    := xz
INITRD_COMPRESS-$(CONFIG_RD_LZO)   := lzo
INITRD_COMPRESS-$(CONFIG_RD_LZ4)   := lz4
917 918 919
# do not export INITRD_COMPRESS, since we didn't actually
# choose a sane default compression above.
# export INITRD_COMPRESS := $(INITRD_COMPRESS-y)
Linus Torvalds's avatar
Linus Torvalds committed
920

921
ifdef CONFIG_MODULE_SIG_ALL
922 923 924
$(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
925 926 927 928 929
else
mod_sign_cmd = true
endif
export mod_sign_cmd

930 931 932 933 934 935 936 937 938 939 940 941
ifdef CONFIG_STACK_VALIDATION
  has_libelf := $(call try-run,\
		echo "int main() {}" | $(HOSTCC) -xc -o /dev/null -lelf -,1,0)
  ifeq ($(has_libelf),1)
    objtool_target := tools/objtool FORCE
  else
    $(warning "Cannot use CONFIG_STACK_VALIDATION, please install libelf-dev, libelf-devel or elfutils-libelf-devel")
    SKIP_STACK_VALIDATION := 1
    export SKIP_STACK_VALIDATION
  endif
endif

942

Linus Torvalds's avatar
Linus Torvalds committed
943
ifeq ($(KBUILD_EXTMOD),)
944
core-y		+= kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
Linus Torvalds's avatar
Linus Torvalds committed
945 946 947

vmlinux-dirs	:= $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
		     $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
948
		     $(net-y) $(net-m) $(libs-y) $(libs-m) $(virt-y)))
Linus Torvalds's avatar
Linus Torvalds committed
949 950

vmlinux-alldirs	:= $(sort $(vmlinux-dirs) $(patsubst %/,%,$(filter %/, \
951
		     $(init-) $(core-) $(drivers-) $(net-) $(libs-) $(virt-))))
Linus Torvalds's avatar
Linus Torvalds committed
952 953 954 955 956 957

init-y		:= $(patsubst %/, %/built-in.o, $(init-y))
core-y		:= $(patsubst %/, %/built-in.o, $(core-y))
drivers-y	:= $(patsubst %/, %/built-in.o, $(drivers-y))
net-y		:= $(patsubst %/, %/built-in.o, $(net-y))
libs-y1		:= $(patsubst %/, %/lib.a, $(libs-y))
958
libs-y2		:= $(filter-out %.a, $(patsubst %/, %/built-in.o, $(libs-y)))
959
virt-y		:= $(patsubst %/, %/built-in.o, $(virt-y))
Linus Torvalds's avatar
Linus Torvalds committed
960

961
# Externally visible symbols (used by link-vmlinux.sh)
962
export KBUILD_VMLINUX_INIT := $(head-y) $(init-y)
963 964
export KBUILD_VMLINUX_MAIN := $(core-y) $(libs-y2) $(drivers-y) $(net-y) $(virt-y)
export KBUILD_VMLINUX_LIBS := $(libs-y1)
965
export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
966
export LDFLAGS_vmlinux
967
# used by scripts/package/Makefile
968
export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) arch Documentation include samples scripts tools)
969

970
vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_INIT) $(KBUILD_VMLINUX_MAIN) $(KBUILD_VMLINUX_LIBS)
Linus Torvalds's avatar
Linus Torvalds committed
971

972 973 974 975 976
# Include targets which we want to execute sequentially if the rest of the
# kernel build went well. If CONFIG_TRIM_UNUSED_KSYMS is set, this might be
# evaluated more than once.
PHONY += vmlinux_prereq
vmlinux_prereq: $(vmlinux-deps) FORCE
977
ifdef CONFIG_HEADERS_CHECK
978
	$(Q)$(MAKE) -f $(srctree)/Makefile headers_check
979
endif
Jan Kiszka's avatar
Jan Kiszka committed
980
ifdef CONFIG_GDB_SCRIPTS
981
	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
982
endif
983
ifdef CONFIG_TRIM_UNUSED_KSYMS
984
	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
985
	  "$(MAKE) -f $(srctree)/Makefile vmlinux"
986
endif
987 988 989

# standalone target for easier testing
include/generated/autoksyms.h: FORCE
990
	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh true
991

992 993 994
ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)

# Final link of vmlinux with optional arch pass after final link
995 996
cmd_link-vmlinux =                                                 \
	$(CONFIG_SHELL) $< $(LD) $(LDFLAGS) $(LDFLAGS_vmlinux) ;    \
997
	$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
998

999
vmlinux: scripts/link-vmlinux.sh vmlinux_prereq $(vmlinux-deps) FORCE
1000
	+$(call if_changed,link-vmlinux)
1001

1002 1003 1004 1005 1006
# Build samples along the rest of the kernel
ifdef CONFIG_SAMPLES
vmlinux-dirs += samples
endif

1007
# The actual objects are generated when descending,
Linus Torvalds's avatar
Linus Torvalds committed
1008
# make sure no implicit rule kicks in
1009
$(sort $(vmlinux-deps)): $(vmlinux-dirs) ;
Linus Torvalds's avatar
Linus Torvalds committed
1010 1011 1012 1013 1014 1015 1016

# Handle descending into subdirectories listed in $(vmlinux-dirs)
# Preset locale variables to speed up the build process. Limit locale
# tweaks to this spot to avoid wrong language settings when running
# make menuconfig etc.
# Error messages still appears in the original language

1017
PHONY += $(vmlinux-dirs)
1018
$(vmlinux-dirs): prepare scripts
Linus Torvalds's avatar
Linus Torvalds committed
1019 1020
	$(Q)$(MAKE) $(build)=$@

1021 1022 1023 1024
define filechk_kernel.release
	echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
endef

1025
# Store (new) KERNELRELEASE string in include/config/kernel.release
Roman Zippel's avatar
Roman Zippel committed
1026
include/config/kernel.release: include/config/auto.conf FORCE
1027
	$(call filechk,kernel.release)
1028 1029


Linus Torvalds's avatar
Linus Torvalds committed
1030
# Things we need to do before we recursively start building the kernel
1031 1032 1033 1034
# 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
1035

1036
# Listed in dependency order
1037
PHONY += prepare archprepare prepare0 prepare1 prepare2 prepare3
1038

1039
# prepare3 is used to check if we are building in a separate output directory,
Linus Torvalds's avatar
Linus Torvalds committed
1040 1041
# and if so do:
# 1) Check that make has not been executed in the kernel src $(srctree)
Roman Zippel's avatar
Roman Zippel committed
1042
prepare3: include/config/kernel.release
Linus Torvalds's avatar
Linus Torvalds committed
1043
ifneq ($(KBUILD_SRC),)
1044
	@$(kecho) '  Using $(srctree) as source for kernel'
1045
	$(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \
1046 1047
		echo >&2 "  $(srctree) is not clean, please run 'make mrproper'"; \
		echo >&2 "  in the '$(srctree)' directory.";\
Linus Torvalds's avatar
Linus Torvalds committed
1048 1049 1050 1051
		/bin/false; \
	fi;
endif

1052 1053 1054 1055
# prepare2 creates a makefile if using a separate output directory.
# From this point forward, .config has been reprocessed, so any rules
# that need to depend on updated CONFIG_* values can be checked here.
prepare2: prepare3 prepare-compiler-check outputmakefile asm-generic
Linus Torvalds's avatar
Linus Torvalds committed
1056

David Howells's avatar
David Howells committed
1057
prepare1: prepare2 $(version_h) include/generated/utsrelease.h \
Sam Ravnborg's avatar
Sam Ravnborg committed
1058
                   include/config/auto.conf
1059
	$(cmd_crmodverdir)
Linus Torvalds's avatar
Linus Torvalds committed
1060

1061
archprepare: archheaders archscripts prepare1 scripts_basic
1062

Emese Revfy's avatar
Emese Revfy committed
1063
prepare0: archprepare gcc-plugins
1064
	$(Q)$(MAKE) $(build)=.
1065

Linus Torvalds's avatar
Linus Torvalds committed
1066
# All the preparing..
1067 1068 1069
prepare: prepare0 prepare-objtool

PHONY += prepare-objtool
1070
prepare-objtool: $(objtool_target)
Linus Torvalds's avatar
Linus Torvalds committed
1071

1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097
# Check for CONFIG flags that require compiler support. Abort the build
# after .config has been processed, but before the kernel build starts.
#
# For security-sensitive CONFIG options, we don't want to fallback and/or
# silently change which compiler flags will be used, since that leads to
# producing kernels with different security feature characteristics
# depending on the compiler used. (For example, "But I selected
# CC_STACKPROTECTOR_STRONG! Why did it build with _REGULAR?!")
PHONY += prepare-compiler-check
prepare-compiler-check: FORCE
# Make sure compiler supports requested stack protector flag.
ifdef stackp-name
  ifeq ($(call cc-option, $(stackp-flag)),)
	@echo Cannot use CONFIG_CC_STACKPROTECTOR_$(stackp-name): \
		  $(stackp-flag) not supported by compiler >&2 && exit 1
  endif
endif
# Make sure compiler does not have buggy stack-protector support.
ifdef stackp-check
  ifneq ($(shell $(CONFIG_SHELL) $(stackp-check) $(CC) $(KBUILD_CPPFLAGS) $(biarch)),y)
	@echo Cannot use CONFIG_CC_STACKPROTECTOR_$(stackp-name): \
                  $(stackp-flag) available but compiler is broken >&2 && exit 1
  endif
endif
	@:

Linus Torvalds's avatar
Linus Torvalds committed
1098 1099 1100 1101 1102 1103 1104
# Generate some files
# ---------------------------------------------------------------------------

# KERNELRELEASE can change from a few different places, meaning version.h
# needs to be updated, so this check is forced on all builds

uts_len := 64
1105 1106 1107 1108 1109 1110 1111
define filechk_utsrelease.h
	if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
	  exit 1;                                                         \
	fi;                                                               \
	(echo \#define UTS_RELEASE \"$(KERNELRELEASE)\";)
endef
Linus Torvalds's avatar
Linus Torvalds committed
1112 1113

define filechk_version.h
1114 1115
	(echo \#define LINUX_VERSION_CODE $(shell                         \
	expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1116
	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))';)
Linus Torvalds's avatar
Linus Torvalds committed
1117 1118
endef

David Howells's avatar
David Howells committed
1119
$(version_h): $(srctree)/Makefile FORCE
Linus Torvalds's avatar
Linus Torvalds committed
1120
	$(call filechk,version.h)
1121
	$(Q)rm -f $(old_version_h)
Linus Torvalds's avatar
Linus Torvalds committed
1122

1123
include/generated/utsrelease.h: include/config/kernel.release FORCE
1124 1125
	$(call filechk,utsrelease.h)

1126 1127
PHONY += headerdep
headerdep:
1128 1129
	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
	$(srctree)/scripts/headerdep.pl -I$(srctree)/include
1130

1131 1132 1133
# ---------------------------------------------------------------------------
# Kernel headers

1134 1135
#Default location for installed headers
export INSTALL_HDR_PATH = $(objtree)/usr
1136

1137
# If we do an all arch process set dst to include/arch-$(hdr-arch)
1138
hdr-dst = $(if $(KBUILD_HEADERS), dst=include/arch-$(hdr-arch), dst=include)
1139

1140 1141 1142
PHONY += archheaders
archheaders:

1143 1144 1145
PHONY += archscripts
archscripts:

1146
PHONY += __headers
1147
__headers: $(version_h) scripts_basic uapi-asm-generic archheaders archscripts
1148
	$(Q)$(MAKE) $(build)=scripts build_unifdef
1149 1150

PHONY += headers_install_all
1151 1152
headers_install_all:
	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh install
1153

1154
PHONY += headers_install
1155
headers_install: __headers
1156 1157
	$(if $(wildcard $(srctree)/arch/$(hdr-arch)/include/uapi/asm/Kbuild),, \
	  $(error Headers not exportable for the $(SRCARCH) architecture))
1158
	$(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include
Nicolas Dichtel's avatar