Makefile 59.1 KB
Newer Older
1
# SPDX-License-Identifier: GPL-2.0
Linus Torvalds's avatar
Linus Torvalds committed
2
VERSION = 4
Linus Torvalds's avatar
Linus Torvalds committed
3
PATCHLEVEL = 19
Linus Torvalds's avatar
Linus Torvalds committed
4
SUBLEVEL = 0
Linus Torvalds's avatar
Linus Torvalds committed
5
EXTRAVERSION = -rc3
Linus Torvalds's avatar
Linus Torvalds committed
6
NAME = Merciless Moray
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:

18 19 20 21
# 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
22

23
# Avoid funny character set dependencies
24
unexport LC_ALL
25 26
LC_COLLATE=C
LC_NUMERIC=C
27
export LC_COLLATE LC_NUMERIC
28

29 30 31
# Avoid interference with shell env settings
unexport GREP_OPTIONS

Linus Torvalds's avatar
Linus Torvalds committed
32 33 34 35 36 37
# 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
38
# unavoidable when linking the built-in.a targets which finally
Linus Torvalds's avatar
Linus Torvalds committed
39 40 41 42 43 44 45 46 47
# 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.

48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70
# 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
71 72 73
# To put more focus on warnings, be less verbose as default
# Use 'make V=1' to see the full commands

74 75
ifeq ("$(origin V)", "command line")
  KBUILD_VERBOSE = $(V)
Linus Torvalds's avatar
Linus Torvalds committed
76 77 78 79 80
endif
ifndef KBUILD_VERBOSE
  KBUILD_VERBOSE = 0
endif

81 82 83 84 85 86 87 88 89 90 91
ifeq ($(KBUILD_VERBOSE),1)
  quiet =
  Q =
else
  quiet=quiet_
  Q = @
endif

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

92
ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
93
  quiet=silent_
94
  tools_silent=s
95 96 97 98
endif

export quiet Q KBUILD_VERBOSE

Linus Torvalds's avatar
Linus Torvalds committed
99 100 101 102 103
# 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/"
104
#
Linus Torvalds's avatar
Linus Torvalds committed
105 106 107 108 109 110 111 112 113
# 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.

114 115
# 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
116 117 118 119
ifeq ($(KBUILD_SRC),)

# OK, Make called in directory where kernel src resides
# Do we want to locate output files in a separate directory?
120 121
ifeq ("$(origin O)", "command line")
  KBUILD_OUTPUT := $(O)
Linus Torvalds's avatar
Linus Torvalds committed
122 123
endif

124 125 126
# Cancel implicit rules on top Makefile
$(CURDIR)/Makefile Makefile: ;

127 128 129 130
ifneq ($(words $(subst :, ,$(CURDIR))), 1)
  $(error main directory cannot contain spaces nor colons)
endif

Linus Torvalds's avatar
Linus Torvalds committed
131 132 133
ifneq ($(KBUILD_OUTPUT),)
# check that the output directory actually exists
saved-output := $(KBUILD_OUTPUT)
134
KBUILD_OUTPUT := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) \
Bjørn Forsman's avatar
Bjørn Forsman committed
135
								&& pwd)
Linus Torvalds's avatar
Linus Torvalds committed
136
$(if $(KBUILD_OUTPUT),, \
137
     $(error failed to create output directory "$(saved-output)"))
Linus Torvalds's avatar
Linus Torvalds committed
138

139 140
PHONY += $(MAKECMDGOALS) sub-make

141
$(filter-out _all sub-make $(CURDIR)/Makefile, $(MAKECMDGOALS)) _all: sub-make
142
	@:
143

144
# Invoke a second make in the output directory, passing relevant variables
145
sub-make:
146
	$(Q)$(MAKE) -C $(KBUILD_OUTPUT) KBUILD_SRC=$(CURDIR) \
147
	-f $(CURDIR)/Makefile $(filter-out _all sub-make,$(MAKECMDGOALS))
Linus Torvalds's avatar
Linus Torvalds committed
148 149 150 151 152 153 154 155 156

# 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),)

157 158 159 160 161
# 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

162 163 164 165 166 167 168
# 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
169 170
# See the file "Documentation/dev-tools/sparse.rst" for more details,
# including where to get the "sparse" utility.
171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189

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

190 191 192 193 194 195 196 197 198 199 200
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
201 202 203

export KBUILD_CHECKSRC KBUILD_EXTMOD KBUILD_SRC

204
objtree		:= .
Linus Torvalds's avatar
Linus Torvalds committed
205 206 207
src		:= $(srctree)
obj		:= $(objtree)

208
VPATH		:= $(srctree)$(if $(KBUILD_EXTMOD),:$(KBUILD_EXTMOD))
Linus Torvalds's avatar
Linus Torvalds committed
209

210
export srctree objtree VPATH
Linus Torvalds's avatar
Linus Torvalds committed
211

212 213 214 215 216 217 218 219 220 221 222
# 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

223 224
clean-targets := %clean mrproper cleandocs
no-dot-config-targets := $(clean-targets) \
225 226
			 cscope gtags TAGS tags help% %docs check% coccicheck \
			 $(version_h) headers_% archheaders archscripts \
227
			 %asm-generic kernelversion %src-pkg
228 229
no-sync-config-targets := $(no-dot-config-targets) install %install \
			   kernelrelease
230

231 232 233 234
config-targets  := 0
mixed-targets   := 0
dot-config      := 1
may-sync-config := 1
235 236 237 238 239 240 241

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

242 243 244 245 246 247 248 249 250 251
ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
	ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
		may-sync-config := 0
	endif
endif

ifneq ($(KBUILD_EXTMOD),)
	may-sync-config := 0
endif

252 253 254 255 256 257 258 259
ifeq ($(KBUILD_EXTMOD),)
        ifneq ($(filter config %config,$(MAKECMDGOALS)),)
                config-targets := 1
                ifneq ($(words $(MAKECMDGOALS)),1)
                        mixed-targets := 1
                endif
        endif
endif
260 261 262 263 264 265 266 267

# For "make -j clean all", "make -j mrproper defconfig all", etc.
ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
        ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
                mixed-targets := 1
        endif
endif

268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301
# install and modules_install need also be processed one by one
ifneq ($(filter install,$(MAKECMDGOALS)),)
        ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
	        mixed-targets := 1
        endif
endif

ifeq ($(mixed-targets),1)
# ===========================================================================
# 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

else

# We need some generic definitions (do not try to remake the file).
scripts/Kbuild.include: ;
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

Linus Torvalds's avatar
Linus Torvalds committed
302 303 304
# 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,
305
# then ARCH is assigned, getting whatever value it gets normally, and
Linus Torvalds's avatar
Linus Torvalds committed
306 307
# SUBARCH is subsequently ignored.

308 309
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
310
				  -e s/arm.*/arm/ -e s/sa110/arm/ \
311
				  -e s/s390x/s390/ -e s/parisc64/parisc/ \
Paul Mundt's avatar
Paul Mundt committed
312
				  -e s/ppc.*/powerpc/ -e s/mips.*/mips/ \
313 314
				  -e s/sh[234].*/sh/ -e s/aarch64.*/arm64/ \
				  -e s/riscv.*/riscv/)
Linus Torvalds's avatar
Linus Torvalds committed
315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333

# 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
334
ARCH		?= $(SUBARCH)
Linus Torvalds's avatar
Linus Torvalds committed
335 336

# Architecture as present in compile.h
337 338
UTS_MACHINE 	:= $(ARCH)
SRCARCH 	:= $(ARCH)
Linus Torvalds's avatar
Linus Torvalds committed
339

340 341 342 343 344 345 346
# Additional ARCH settings for x86
ifeq ($(ARCH),i386)
        SRCARCH := x86
endif
ifeq ($(ARCH),x86_64)
        SRCARCH := x86
endif
347

Sam Ravnborg's avatar
Sam Ravnborg committed
348
# Additional ARCH settings for sparc
349 350 351
ifeq ($(ARCH),sparc32)
       SRCARCH := sparc
endif
352
ifeq ($(ARCH),sparc64)
Sam Ravnborg's avatar
Sam Ravnborg committed
353
       SRCARCH := sparc
354
endif
355

356 357 358 359 360
# Additional ARCH settings for sh
ifeq ($(ARCH),sh64)
       SRCARCH := sh
endif

361
KCONFIG_CONFIG	?= .config
362
export KCONFIG_CONFIG
363

Linus Torvalds's avatar
Linus Torvalds committed
364 365 366 367 368
# 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)

369 370 371
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)
372

373 374
HOSTCC       = gcc
HOSTCXX      = g++
375
KBUILD_HOSTCFLAGS   := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 \
376 377 378 379 380
		-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
381 382 383 384 385 386 387 388 389 390 391

# 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
392 393
LEX		= flex
YACC		= bison
Linus Torvalds's avatar
Linus Torvalds committed
394 395
AWK		= awk
GENKSYMS	= scripts/genksyms/genksyms
396
INSTALLKERNEL  := installkernel
Linus Torvalds's avatar
Linus Torvalds committed
397 398
DEPMOD		= /sbin/depmod
PERL		= perl
399
PYTHON		= python
400 401
PYTHON2		= python2
PYTHON3		= python3
Linus Torvalds's avatar
Linus Torvalds committed
402 403
CHECK		= sparse

404
CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
405
		  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
406
NOSTDINC_FLAGS  =
407 408 409
CFLAGS_MODULE   =
AFLAGS_MODULE   =
LDFLAGS_MODULE  =
Linus Torvalds's avatar
Linus Torvalds committed
410 411
CFLAGS_KERNEL	=
AFLAGS_KERNEL	=
412
LDFLAGS_vmlinux =
Linus Torvalds's avatar
Linus Torvalds committed
413

414 415
# Use USERINCLUDE when you must reference the UAPI directories only.
USERINCLUDE    := \
416 417
		-I$(srctree)/arch/$(SRCARCH)/include/uapi \
		-I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
418
		-I$(srctree)/include/uapi \
419
		-I$(objtree)/include/generated/uapi \
420 421
                -include $(srctree)/include/linux/kconfig.h

Linus Torvalds's avatar
Linus Torvalds committed
422 423
# Use LINUXINCLUDE when you must reference the include/ directory.
# Needed to be compatible with the O= option
424
LINUXINCLUDE    := \
425 426
		-I$(srctree)/arch/$(SRCARCH)/include \
		-I$(objtree)/arch/$(SRCARCH)/include/generated \
427
		$(if $(KBUILD_SRC), -I$(srctree)/include) \
428 429
		-I$(objtree)/include \
		$(USERINCLUDE)
Linus Torvalds's avatar
Linus Torvalds committed
430

431
KBUILD_AFLAGS   := -D__ASSEMBLY__
432
KBUILD_CFLAGS   := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
433
		   -fno-strict-aliasing -fno-common -fshort-wchar \
434
		   -Werror-implicit-function-declaration \
435
		   -Wno-format-security \
436 437
		   -std=gnu89
KBUILD_CPPFLAGS := -D__KERNEL__
438 439
KBUILD_AFLAGS_KERNEL :=
KBUILD_CFLAGS_KERNEL :=
440 441 442
KBUILD_AFLAGS_MODULE  := -DMODULE
KBUILD_CFLAGS_MODULE  := -DMODULE
KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
443
KBUILD_LDFLAGS :=
444
GCC_PLUGINS_CFLAGS :=
Linus Torvalds's avatar
Linus Torvalds committed
445

446
export ARCH SRCARCH CONFIG_SHELL HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE AS LD CC
447
export CPP AR NM STRIP OBJCOPY OBJDUMP KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS
448
export MAKE LEX YACC AWK GENKSYMS INSTALLKERNEL PERL PYTHON PYTHON2 PYTHON3 UTS_MACHINE
449
export HOSTCXX KBUILD_HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
Linus Torvalds's avatar
Linus Torvalds committed
450

451
export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
452 453
export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN
454
export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
455
export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
456
export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
457
export KBUILD_ARFLAGS
Linus Torvalds's avatar
Linus Torvalds committed
458 459 460 461 462 463 464 465

# 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

466 467 468
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
469 470
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
471 472 473 474

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

475
# Basic helpers built in scripts/basic/
476
PHONY += scripts_basic
Linus Torvalds's avatar
Linus Torvalds committed
477 478
scripts_basic:
	$(Q)$(MAKE) $(build)=scripts/basic
479
	$(Q)rm -f .tmp_quiet_recordmcount
Linus Torvalds's avatar
Linus Torvalds committed
480

481 482 483
# To avoid any implicit rule to kick in, define an empty command.
scripts/basic/%: scripts_basic ;

484
PHONY += outputmakefile
485 486 487
# 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
488
outputmakefile:
489
ifneq ($(KBUILD_SRC),)
490
	$(Q)ln -fsn $(srctree) source
491 492 493
	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile \
	    $(srctree) $(objtree) $(VERSION) $(PATCHLEVEL)
endif
Linus Torvalds's avatar
Linus Torvalds committed
494

495 496 497 498 499 500 501 502 503 504
ifeq ($(cc-name),clang)
ifneq ($(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)
505 506
KBUILD_CFLAGS += $(call cc-option, -no-integrated-as)
KBUILD_AFLAGS += $(call cc-option, -no-integrated-as)
507 508
endif

509
RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
510
RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
511
RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
512
RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
513
RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
514
RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
515
export RETPOLINE_CFLAGS
516
export RETPOLINE_VDSO_CFLAGS
517

518 519 520
KBUILD_CFLAGS	+= $(call cc-option,-fno-PIE)
KBUILD_AFLAGS	+= $(call cc-option,-fno-PIE)

Peter Zijlstra's avatar
Peter Zijlstra committed
521
# check for 'asm goto'
522
ifeq ($(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC) $(KBUILD_CFLAGS)), y)
Peter Zijlstra's avatar
Peter Zijlstra committed
523 524 525 526 527
  CC_HAVE_ASM_GOTO := 1
  KBUILD_CFLAGS += -DCC_HAVE_ASM_GOTO
  KBUILD_AFLAGS += -DCC_HAVE_ASM_GOTO
endif

528 529 530 531 532 533
# 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.
CC_VERSION_TEXT = $(shell $(CC) --version | head -n 1)

Linus Torvalds's avatar
Linus Torvalds committed
534 535 536 537 538 539 540 541
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'
542
include arch/$(SRCARCH)/Makefile
543
export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
Linus Torvalds's avatar
Linus Torvalds committed
544

545 546 547 548
config: scripts_basic outputmakefile FORCE
	$(Q)$(MAKE) $(build)=scripts/kconfig $@

%config: scripts_basic outputmakefile FORCE
Linus Torvalds's avatar
Linus Torvalds committed
549 550 551 552 553 554 555
	$(Q)$(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.

556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593
# 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

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

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

export KBUILD_MODULES KBUILD_BUILTIN

Linus Torvalds's avatar
Linus Torvalds committed
594 595 596
ifeq ($(KBUILD_EXTMOD),)
# Objects we will link into vmlinux / subdirs we need to visit
init-y		:= init/
597
drivers-y	:= drivers/ sound/ firmware/
Linus Torvalds's avatar
Linus Torvalds committed
598 599 600
net-y		:= net/
libs-y		:= lib/
core-y		:= usr/
601
virt-y		:= virt/
Linus Torvalds's avatar
Linus Torvalds committed
602 603 604
endif # KBUILD_EXTMOD

ifeq ($(dot-config),1)
605
include include/config/auto.conf
606 607 608 609 610 611 612 613 614 615 616
endif

# 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,)
617
export CFLAGS_GCOV
618 619 620 621 622 623 624

# 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 :=
include arch/$(SRCARCH)/Makefile
Linus Torvalds's avatar
Linus Torvalds committed
625

626
ifeq ($(dot-config),1)
627
ifeq ($(may-sync-config),1)
628 629 630
# 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.
631
-include include/config/auto.conf.cmd
Linus Torvalds's avatar
Linus Torvalds committed
632 633

# To avoid any implicit rule to kick in, define an empty command
634
$(KCONFIG_CONFIG) include/config/auto.conf.cmd: ;
Linus Torvalds's avatar
Linus Torvalds committed
635

636 637 638
# 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).
639
include/config/%.conf: $(KCONFIG_CONFIG) include/config/auto.conf.cmd
640
	$(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
641
else
642 643 644
# 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
645 646 647
PHONY += include/config/auto.conf

include/config/auto.conf:
648
	$(Q)test -e include/generated/autoconf.h -a -e $@ || (		\
649 650 651 652 653
	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 ;							\
654 655
	/bin/false)

656
endif # may-sync-config
657
endif # $(dot-config)
Linus Torvalds's avatar
Linus Torvalds committed
658

659
KBUILD_CFLAGS	+= $(call cc-option,-fno-delete-null-pointer-checks,)
660
KBUILD_CFLAGS	+= $(call cc-disable-warning,frame-address,)
661 662 663
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)
664

Linus Torvalds's avatar
Linus Torvalds committed
665
ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
666 667
KBUILD_CFLAGS	+= $(call cc-option,-Oz,-Os)
KBUILD_CFLAGS	+= $(call cc-disable-warning,maybe-uninitialized,)
Linus Torvalds's avatar
Linus Torvalds committed
668
else
669
ifdef CONFIG_PROFILE_ALL_BRANCHES
670
KBUILD_CFLAGS	+= -O2 $(call cc-disable-warning,maybe-uninitialized,)
671 672 673
else
KBUILD_CFLAGS   += -O2
endif
Linus Torvalds's avatar
Linus Torvalds committed
674 675
endif

676 677 678
KBUILD_CFLAGS += $(call cc-ifversion, -lt, 0409, \
			$(call cc-disable-warning,maybe-uninitialized,))

679 680 681
# Tell gcc to never replace conditional load with a non-conditional one
KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)

682
include scripts/Makefile.kcov
Emese Revfy's avatar
Emese Revfy committed
683 684
include scripts/Makefile.gcc-plugins

Andi Kleen's avatar
Andi Kleen committed
685 686 687 688 689 690 691 692 693 694
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

695
ifneq ($(CONFIG_FRAME_WARN),0)
696 697 698
KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
endif

699
stackp-flags-$(CONFIG_CC_HAS_STACKPROTECTOR_NONE) := -fno-stack-protector
700 701
stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
702 703

KBUILD_CFLAGS += $(stackp-flags-y)
704

705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723
ifeq ($(cc-name),clang)
KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier)
KBUILD_CFLAGS += $(call cc-disable-warning, gnu)
KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
# 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,)
KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior)
else

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

724
KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
Linus Torvalds's avatar
Linus Torvalds committed
725
ifdef CONFIG_FRAME_POINTER
726
KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
Linus Torvalds's avatar
Linus Torvalds committed
727
else
728 729 730 731 732 733
# 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
734
KBUILD_CFLAGS	+= -fomit-frame-pointer
Linus Torvalds's avatar
Linus Torvalds committed
735
endif
736
endif
Linus Torvalds's avatar
Linus Torvalds committed
737

738 739
KBUILD_CFLAGS   += $(call cc-option, -fno-var-tracking-assignments)

Linus Torvalds's avatar
Linus Torvalds committed
740
ifdef CONFIG_DEBUG_INFO
741 742 743
ifdef CONFIG_DEBUG_INFO_SPLIT
KBUILD_CFLAGS   += $(call cc-option, -gsplit-dwarf, -g)
else
744
KBUILD_CFLAGS	+= -g
745
endif
746
KBUILD_AFLAGS	+= -Wa,-gdwarf-2
Linus Torvalds's avatar
Linus Torvalds committed
747
endif
748 749 750
ifdef CONFIG_DEBUG_INFO_DWARF4
KBUILD_CFLAGS	+= $(call cc-option, -gdwarf-4,)
endif
Linus Torvalds's avatar
Linus Torvalds committed
751

752
ifdef CONFIG_DEBUG_INFO_REDUCED
753 754
KBUILD_CFLAGS 	+= $(call cc-option, -femit-struct-debug-baseonly) \
		   $(call cc-option,-fno-var-tracking)
755 756
endif

757
ifdef CONFIG_FUNCTION_TRACER
758 759 760
ifndef CC_FLAGS_FTRACE
CC_FLAGS_FTRACE := -pg
endif
761 762 763 764 765 766
ifdef CONFIG_FTRACE_MCOUNT_RECORD
  # gcc 5 supports generating the mcount tables directly
  ifeq ($(call cc-option-yn,-mrecord-mcount),y)
    CC_FLAGS_FTRACE	+= -mrecord-mcount
    export CC_USING_RECORD_MCOUNT := 1
  endif
767 768 769 770 771 772
  ifdef CONFIG_HAVE_NOP_MCOUNT
    ifeq ($(call cc-option-yn, -mnop-mcount),y)
      CC_FLAGS_FTRACE	+= -mnop-mcount
      CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
    endif
  endif
773
endif
774
ifdef CONFIG_HAVE_FENTRY
775 776 777 778
  ifeq ($(call cc-option-yn, -mfentry),y)
    CC_FLAGS_FTRACE	+= -mfentry
    CC_FLAGS_USING	+= -DCC_USING_FENTRY
  endif
779
endif
780 781 782
export CC_FLAGS_FTRACE
KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
783
ifdef CONFIG_DYNAMIC_FTRACE
784
	ifdef CONFIG_HAVE_C_RECORDMCOUNT
785 786 787 788
		BUILD_C_RECORDMCOUNT := y
		export BUILD_C_RECORDMCOUNT
	endif
endif
789 790
endif

791 792 793 794 795
# We trigger additional mismatches with less inlining
ifdef CONFIG_DEBUG_SECTION_MISMATCH
KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
endif

796
ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
797 798
KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
LDFLAGS_vmlinux += --gc-sections
799 800
endif

801
# arch Makefile may override CC so keep this after arch Makefile is included
802
NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
803

Linus Torvalds's avatar
Linus Torvalds committed
804
# warn about C99 declaration after statement
805
KBUILD_CFLAGS += $(call cc-option,-Wdeclaration-after-statement,)
Linus Torvalds's avatar
Linus Torvalds committed
806

807
# disable pointer signed / unsigned warnings in gcc 4.0
808
KBUILD_CFLAGS += $(call cc-disable-warning, pointer-sign)
Linus Torvalds's avatar
Linus Torvalds committed
809

810 811 812
# disable stringop warnings in gcc 8+
KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)

813
# disable invalid "can't wrap" optimizations for signed / pointers
814
KBUILD_CFLAGS	+= $(call cc-option,-fno-strict-overflow)
815

816 817 818 819 820 821 822 823 824
# 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)

825 826 827
# Make sure -fstack-check isn't enabled (like gentoo apparently did)
KBUILD_CFLAGS  += $(call cc-option,-fno-stack-check,)

828 829 830
# conserve stack if available
KBUILD_CFLAGS   += $(call cc-option,-fconserve-stack)

831 832 833 834 835 836
# 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)

837 838 839
# Prohibit date/time macros, which would make the build non-deterministic
KBUILD_CFLAGS   += $(call cc-option,-Werror=date-time)

840 841 842
# enforce correct pointer usage
KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)

843 844 845
# Require designated initializers for all marked structures
KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)

846 847 848
# change __FILE__ to the relative path from the srctree
KBUILD_CFLAGS	+= $(call cc-option,-fmacro-prefix-map=$(srctree)/=)

849 850 851
# use the deterministic mode of AR if available
KBUILD_ARFLAGS := $(call ar-option,D)

852 853
include scripts/Makefile.kasan
include scripts/Makefile.extrawarn
854
include scripts/Makefile.ubsan
855

856 857 858 859 860
# 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)
861

Roland McGrath's avatar
Roland McGrath committed
862
# Use --build-id when available.
863
LDFLAGS_BUILD_ID := $(call ld-option, --build-id)
864
KBUILD_LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID)
Roland McGrath's avatar
Roland McGrath committed
865 866
LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)

867
ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
868
LDFLAGS_vmlinux	+= $(call ld-option, -X,)
869 870
endif

871 872 873
# insure the checker run with the right endianness
CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)

874 875 876
# the checker needs the correct machine size
CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)

Linus Torvalds's avatar
Linus Torvalds committed
877
# Default kernel image to build when no specific target is given.
878
# KBUILD_IMAGE may be overruled on the command line or
Linus Torvalds's avatar
Linus Torvalds committed
879 880 881 882 883 884 885 886 887 888
# 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

889 890 891 892 893 894 895
#
# 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
896 897 898
#
# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
# relocations required by build roots.  This is not defined in the
899
# makefile but the argument can be passed to make if needed.
Linus Torvalds's avatar
Linus Torvalds committed
900 901
#

902
MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
Linus Torvalds's avatar
Linus Torvalds committed
903 904
export MODLIB

905
#
906 907 908 909
# 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.
910

911 912
ifdef INSTALL_MOD_STRIP
ifeq ($(INSTALL_MOD_STRIP),1)
913
mod_strip_cmd = $(STRIP) --strip-debug
914
else
915
mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
916 917
endif # INSTALL_MOD_STRIP=1
else
918
mod_strip_cmd = true
919 920 921
endif # INSTALL_MOD_STRIP
export mod_strip_cmd

922 923 924 925 926 927 928
# 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
929
    mod_compress_cmd = gzip -n -f
930 931
  endif # CONFIG_MODULE_COMPRESS_GZIP
  ifdef CONFIG_MODULE_COMPRESS_XZ
932
    mod_compress_cmd = xz -f
933 934 935 936
  endif # CONFIG_MODULE_COMPRESS_XZ
endif # CONFIG_MODULE_COMPRESS
export mod_compress_cmd

937 938 939
# 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
940 941 942 943 944 945
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
946 947 948
# 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
949

950
ifdef CONFIG_MODULE_SIG_ALL
951 952 953
$(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
954 955 956 957 958
else
mod_sign_cmd = true
endif
export mod_sign_cmd

959 960 961 962 963 964
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
965 966
    ifdef CONFIG_UNWINDER_ORC
      $(error "Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel")
967 968 969
    else
      $(warning "Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel")
    endif
970 971 972 973 974
    SKIP_STACK_VALIDATION := 1
    export SKIP_STACK_VALIDATION
  endif
endif

975

Linus Torvalds's avatar
Linus Torvalds committed
976
ifeq ($(KBUILD_EXTMOD),)
977
core-y		+= kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
Linus Torvalds's avatar
Linus Torvalds committed
978 979 980

vmlinux-dirs	:= $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
		     $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
981
		     $(net-y) $(net-m) $(libs-y) $(libs-m) $(virt-y)))
Linus Torvalds's avatar
Linus Torvalds committed
982 983

vmlinux-alldirs	:= $(sort $(vmlinux-dirs) $(patsubst %/,%,$(filter %/, \
984
		     $(init-) $(core-) $(drivers-) $(net-) $(libs-) $(virt-))))
Linus Torvalds's avatar
Linus Torvalds committed
985

986 987 988 989
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
990
libs-y1		:= $(patsubst %/, %/lib.a, $(libs-y))
991 992
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
993

994
# Externally visible symbols (used by link-vmlinux.sh)
995
export KBUILD_VMLINUX_INIT := $(head-y) $(init-y)
996 997
export KBUILD_VMLINUX_MAIN := $(core-y) $(libs-y2) $(drivers-y) $(net-y) $(virt-y)
export KBUILD_VMLINUX_LIBS := $(libs-y1)
998
export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
999
export LDFLAGS_vmlinux
1000
# used by scripts/package/Makefile
1001
export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) arch Documentation include samples scripts tools)
1002

1003
vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_INIT) $(KBUILD_VMLINUX_MAIN) $(KBUILD_VMLINUX_LIBS)
Linus Torvalds's avatar
Linus Torvalds committed
1004

1005 1006 1007
# Recurse until adjust_autoksyms.sh is satisfied
PHONY += autoksyms_recursive
autoksyms_recursive: $(vmlinux-deps)
1008
ifdef CONFIG_TRIM_UNUSED_KSYMS
1009
	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1010
	  "$(MAKE) -f $(srctree)/Makefile vmlinux"
1011
endif
1012

1013 1014 1015 1016 1017 1018 1019
# 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

1020 1021 1022 1023 1024
autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)

$(autoksyms_h):
	$(Q)mkdir -p $(dir $@)
	$(Q)touch $@
1025

1026 1027 1028
ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)

# Final link of vmlinux with optional arch pass after final link
1029
cmd_link-vmlinux =                                                 \
1030
	$(CONFIG_SHELL) $< $(LD) $(KBUILD_LDFLAGS) $(LDFLAGS_vmlinux) ;    \
1031
	$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1032

1033 1034 1035 1036 1037 1038 1039
vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
ifdef CONFIG_HEADERS_CHECK
	$(Q)$(MAKE) -f $(srctree)/Makefile headers_check
endif
ifdef CONFIG_GDB_SCRIPTS
	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
endif
1040
	+$(call if_changed,link-vmlinux)
1041

1042
# Build samples along the rest of the kernel. This needs headers_install.
1043 1044
ifdef CONFIG_SAMPLES
vmlinux-dirs += samples
1045
samples: headers_install
1046 1047
endif

1048
# The actual objects are generated when descending,
Linus Torvalds's avatar
Linus Torvalds committed
1049
# make sure no implicit rule kicks in
1050
$(sort $(vmlinux-deps)): $(vmlinux-dirs) ;
Linus Torvalds's avatar
Linus Torvalds committed
1051 1052 1053 1054 1055 1056 1057

# 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

1058
PHONY += $(vmlinux-dirs)
1059
$(vmlinux-dirs): prepare scripts
1060
	$(Q)$(MAKE) $(build)=$@ need-builtin=1
Linus Torvalds's avatar
Linus Torvalds committed
1061

1062 1063 1064 1065
define filechk_kernel.release
	echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
endef

1066
# Store (new) KERNELRELEASE string in include/config/kernel.release
1067
include/config/kernel.release: $(srctree)/Makefile FORCE
1068
	$(call filechk,kernel.release)
1069

1070 1071 1072 1073
# Additional helpers built in scripts/
# Carefully list dependencies so we do not try to build scripts twice
# in parallel
PHONY += scripts
1074
scripts: scripts_basic asm-generic gcc-plugins $(autoksyms_h)
1075
	$(Q)$(MAKE) $(build)=$(@)
1076

Linus Torvalds's avatar
Linus Torvalds committed
1077
# Things we need to do before we recursively start building the kernel
1078 1079 1080 1081
# 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
1082

1083
# Listed in dependency order
1084
PHONY += prepare archprepare prepare0 prepare1 prepare2 prepare3
1085

1086
# prepare3 is used to check if we are building in a separate output directory,
Linus Torvalds's avatar
Linus Torvalds committed
1087 1088
# and if so do:
# 1) Check that make has not been executed in the kernel src $(srctree)
Roman Zippel's avatar
Roman Zippel committed
1089
prepare3: include/config/kernel.release
Linus Torvalds's avatar
Linus Torvalds committed
1090
ifneq ($(KBUILD_SRC),)
1091
	@$(kecho) '  Using $(srctree) as source for kernel'
1092
	$(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \
1093 1094
		echo >&2 "  $(srctree) is not clean, please run 'make mrproper'"; \
		echo >&2 "  in the '$(srctree)' directory.";\
Linus Torvalds's avatar
Linus Torvalds committed
1095 1096 1097 1098
		/bin/false; \
	fi;
endif

1099 1100 1101
# 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.
1102
prepare2: prepare3 outputmakefile asm-generic
Linus Torvalds's avatar
Linus Torvalds committed
1103

1104
prepare1: prepare2 $(version_h) $(autoksyms_h) include/generated/utsrelease.h
1105
	$(cmd_crmodverdir)
Linus Torvalds's avatar
Linus Torvalds committed
1106

1107
archprepare: archheaders archscripts prepare1 scripts_basic
1108

Emese Revfy's avatar
Emese Revfy committed
1109
prepare0: archprepare gcc-plugins
1110
	$(Q)$(MAKE) $(build)=.
1111

Linus Torvalds's avatar
Linus Torvalds committed
1112
# All the preparing..
1113 1114
prepare: prepare0 prepare-objtool

1115 1116 1117 1118 1119 1120 1121 1122 1123
# Support for using generic headers in asm-generic
PHONY += asm-generic uapi-asm-generic
asm-generic: uapi-asm-generic
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
	            src=asm obj=arch/$(SRCARCH)/include/generated/asm
uapi-asm-generic:
	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
	            src=uapi/asm obj=arch/$(SRCARCH)/include/generated/uapi/asm

1124
PHONY += prepare-objtool
1125
prepare-objtool: $(objtool_target)
Linus Torvalds's avatar
Linus Torvalds committed
1126 1127 1128 1129 1130 1131 1132 1133

# 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
1134 1135 1136 1137 1138 1139 1140
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
1141 1142

define filechk_version.h
1143 1144
	(echo \#define LINUX_VERSION_CODE $(shell                         \
	expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1145
	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))';)
Linus Torvalds's avatar
Linus Torvalds committed
1146 1147
endef

1148
$(version_h): FORCE
Linus Torvalds's avatar
Linus Torvalds committed
1149
	$(call filechk,version.h)
1150
	$(Q)rm -f $(old_version_h)
Linus Torvalds's avatar
Linus Torvalds committed
1151

1152
include/generated/utsrelease.h: include/config/kernel.release FORCE
1153 1154
	$(call filechk,utsrelease.h)

1155 1156
PHONY += headerdep
headerdep:
1157 1158
	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
	$(srctree)/scripts/headerdep.pl -I$(srctree)/include
1159

1160 1161 1162
# ---------------------------------------------------------------------------
# Kernel headers

1163 1164
#Default location for installed headers
export INSTALL_HDR_PATH = $(objtree)/usr
1165

1166 1167
# If we do an all arch process set dst to include/arch-$(SRCARCH)
hdr-dst = $(if $(KBUILD_HEADERS), dst=include/arch-$(SRCARCH), dst=include)
1168

1169 1170 1171
PHONY += archheaders
archheaders:

1172 1173 1174
PHONY += archscripts
archscripts:

1175
PHONY += __headers
1176
__headers: $(version_h) scripts_basic uapi-asm-generic archheaders archscripts
1177
	$(Q)$(MAKE) $(build)=scripts build_unifdef
1178 1179

PHONY += headers_install_all
1180 1181
headers_install_all:
	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh install
1182

1183
PHONY += headers_install
1184
headers_install: __headers
1185
	$(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1186
	  $(error Headers not exportable for the $(SRCARCH) architecture))
1187
	$(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include
1188
	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi $(hdr-dst)
1189

1190 1191
PHONY += headers_check_all
headers_check_all: headers_install_all
1192
	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh check
1193

1194 1195
PHONY += headers_check
headers_check: headers_install
1196
	$(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include HDRCHECK=1
1197
	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi $(hdr-dst) HDRCHECK=1
1198

1199 1200 1201 1202 1203
# ---------------------------------------------------------------------------
# Kernel selftest

PHONY += kselftest
kselftest: