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   1# SPDX-License-Identifier: GPL-2.0
   2VERSION = 5
   3PATCHLEVEL = 1
   4SUBLEVEL = 0
   5EXTRAVERSION =
   6NAME = Shy Crocodile
   7
   8# *DOCUMENTATION*
   9# To see a list of typical targets execute "make help"
  10# More info can be located in ./README
  11# Comments in this file are targeted only to the developer, do not
  12# expect to learn how to build the kernel reading this file.
  13
  14# That's our default target when none is given on the command line
  15PHONY := _all
  16_all:
  17
  18# We are using a recursive build, so we need to do a little thinking
  19# to get the ordering right.
  20#
  21# Most importantly: sub-Makefiles should only ever modify files in
  22# their own directory. If in some directory we have a dependency on
  23# a file in another dir (which doesn't happen often, but it's often
  24# unavoidable when linking the built-in.a targets which finally
  25# turn into vmlinux), we will call a sub make in that other dir, and
  26# after that we are sure that everything which is in that other dir
  27# is now up to date.
  28#
  29# The only cases where we need to modify files which have global
  30# effects are thus separated out and done before the recursive
  31# descending is started. They are now explicitly listed as the
  32# prepare rule.
  33
  34ifneq ($(sub_make_done),1)
  35
  36# Do not use make's built-in rules and variables
  37# (this increases performance and avoids hard-to-debug behaviour)
  38MAKEFLAGS += -rR
  39
  40# Avoid funny character set dependencies
  41unexport LC_ALL
  42LC_COLLATE=C
  43LC_NUMERIC=C
  44export LC_COLLATE LC_NUMERIC
  45
  46# Avoid interference with shell env settings
  47unexport GREP_OPTIONS
  48
  49# Beautify output
  50# ---------------------------------------------------------------------------
  51#
  52# Normally, we echo the whole command before executing it. By making
  53# that echo $($(quiet)$(cmd)), we now have the possibility to set
  54# $(quiet) to choose other forms of output instead, e.g.
  55#
  56#         quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
  57#         cmd_cc_o_c       = $(CC) $(c_flags) -c -o $@ $<
  58#
  59# If $(quiet) is empty, the whole command will be printed.
  60# If it is set to "quiet_", only the short version will be printed.
  61# If it is set to "silent_", nothing will be printed at all, since
  62# the variable $(silent_cmd_cc_o_c) doesn't exist.
  63#
  64# A simple variant is to prefix commands with $(Q) - that's useful
  65# for commands that shall be hidden in non-verbose mode.
  66#
  67#       $(Q)ln $@ :<
  68#
  69# If KBUILD_VERBOSE equals 0 then the above command will be hidden.
  70# If KBUILD_VERBOSE equals 1 then the above command is displayed.
  71#
  72# To put more focus on warnings, be less verbose as default
  73# Use 'make V=1' to see the full commands
  74
  75ifeq ("$(origin V)", "command line")
  76  KBUILD_VERBOSE = $(V)
  77endif
  78ifndef KBUILD_VERBOSE
  79  KBUILD_VERBOSE = 0
  80endif
  81
  82ifeq ($(KBUILD_VERBOSE),1)
  83  quiet =
  84  Q =
  85else
  86  quiet=quiet_
  87  Q = @
  88endif
  89
  90# If the user is running make -s (silent mode), suppress echoing of
  91# commands
  92
  93ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
  94  quiet=silent_
  95endif
  96
  97export quiet Q KBUILD_VERBOSE
  98
  99# kbuild supports saving output files in a separate directory.
 100# To locate output files in a separate directory two syntaxes are supported.
 101# In both cases the working directory must be the root of the kernel src.
 102# 1) O=
 103# Use "make O=dir/to/store/output/files/"
 104#
 105# 2) Set KBUILD_OUTPUT
 106# Set the environment variable KBUILD_OUTPUT to point to the directory
 107# where the output files shall be placed.
 108# export KBUILD_OUTPUT=dir/to/store/output/files/
 109# make
 110#
 111# The O= assignment takes precedence over the KBUILD_OUTPUT environment
 112# variable.
 113
 114# KBUILD_SRC is not intended to be used by the regular user (for now),
 115# it is set on invocation of make with KBUILD_OUTPUT or O= specified.
 116
 117# OK, Make called in directory where kernel src resides
 118# Do we want to locate output files in a separate directory?
 119ifeq ("$(origin O)", "command line")
 120  KBUILD_OUTPUT := $(O)
 121endif
 122
 123ifneq ($(words $(subst :, ,$(CURDIR))), 1)
 124  $(error main directory cannot contain spaces nor colons)
 125endif
 126
 127ifneq ($(KBUILD_OUTPUT),)
 128# check that the output directory actually exists
 129saved-output := $(KBUILD_OUTPUT)
 130KBUILD_OUTPUT := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) \
 131                                                                && pwd)
 132$(if $(KBUILD_OUTPUT),, \
 133     $(error failed to create output directory "$(saved-output)"))
 134
 135# Look for make include files relative to root of kernel src
 136#
 137# This does not become effective immediately because MAKEFLAGS is re-parsed
 138# once after the Makefile is read.  It is OK since we are going to invoke
 139# 'sub-make' below.
 140MAKEFLAGS += --include-dir=$(CURDIR)
 141
 142need-sub-make := 1
 143else
 144
 145# Do not print "Entering directory ..." at all for in-tree build.
 146MAKEFLAGS += --no-print-directory
 147
 148endif # ifneq ($(KBUILD_OUTPUT),)
 149
 150ifneq ($(filter 3.%,$(MAKE_VERSION)),)
 151# 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
 152# We need to invoke sub-make to avoid implicit rules in the top Makefile.
 153need-sub-make := 1
 154# Cancel implicit rules for this Makefile.
 155$(lastword $(MAKEFILE_LIST)): ;
 156endif
 157
 158export sub_make_done := 1
 159
 160ifeq ($(need-sub-make),1)
 161
 162PHONY += $(MAKECMDGOALS) sub-make
 163
 164$(filter-out _all sub-make $(CURDIR)/Makefile, $(MAKECMDGOALS)) _all: sub-make
 165        @:
 166
 167# Invoke a second make in the output directory, passing relevant variables
 168sub-make:
 169        $(Q)$(MAKE) \
 170        $(if $(KBUILD_OUTPUT),-C $(KBUILD_OUTPUT) KBUILD_SRC=$(CURDIR)) \
 171        -f $(CURDIR)/Makefile $(filter-out _all sub-make,$(MAKECMDGOALS))
 172
 173endif # need-sub-make
 174endif # sub_make_done
 175
 176# We process the rest of the Makefile if this is the final invocation of make
 177ifeq ($(need-sub-make),)
 178
 179# Do not print "Entering directory ...",
 180# but we want to display it when entering to the output directory
 181# so that IDEs/editors are able to understand relative filenames.
 182MAKEFLAGS += --no-print-directory
 183
 184# Call a source code checker (by default, "sparse") as part of the
 185# C compilation.
 186#
 187# Use 'make C=1' to enable checking of only re-compiled files.
 188# Use 'make C=2' to enable checking of *all* source files, regardless
 189# of whether they are re-compiled or not.
 190#
 191# See the file "Documentation/dev-tools/sparse.rst" for more details,
 192# including where to get the "sparse" utility.
 193
 194ifeq ("$(origin C)", "command line")
 195  KBUILD_CHECKSRC = $(C)
 196endif
 197ifndef KBUILD_CHECKSRC
 198  KBUILD_CHECKSRC = 0
 199endif
 200
 201# Use make M=dir to specify directory of external module to build
 202# Old syntax make ... SUBDIRS=$PWD is still supported
 203# Setting the environment variable KBUILD_EXTMOD take precedence
 204ifdef SUBDIRS
 205  $(warning ================= WARNING ================)
 206  $(warning 'SUBDIRS' will be removed after Linux 5.3)
 207  $(warning Please use 'M=' or 'KBUILD_EXTMOD' instead)
 208  $(warning ==========================================)
 209  KBUILD_EXTMOD ?= $(SUBDIRS)
 210endif
 211
 212ifeq ("$(origin M)", "command line")
 213  KBUILD_EXTMOD := $(M)
 214endif
 215
 216ifeq ($(KBUILD_SRC),)
 217        # building in the source tree
 218        srctree := .
 219else
 220        ifeq ($(KBUILD_SRC)/,$(dir $(CURDIR)))
 221                # building in a subdirectory of the source tree
 222                srctree := ..
 223        else
 224                srctree := $(KBUILD_SRC)
 225        endif
 226endif
 227
 228export KBUILD_CHECKSRC KBUILD_EXTMOD KBUILD_SRC
 229
 230objtree         := .
 231src             := $(srctree)
 232obj             := $(objtree)
 233
 234VPATH           := $(srctree)
 235
 236export srctree objtree VPATH
 237
 238# To make sure we do not include .config for any of the *config targets
 239# catch them early, and hand them over to scripts/kconfig/Makefile
 240# It is allowed to specify more targets when calling make, including
 241# mixing *config targets and build targets.
 242# For example 'make oldconfig all'.
 243# Detect when mixed targets is specified, and make a second invocation
 244# of make so .config is not included in this case either (for *config).
 245
 246version_h := include/generated/uapi/linux/version.h
 247old_version_h := include/linux/version.h
 248
 249clean-targets := %clean mrproper cleandocs
 250no-dot-config-targets := $(clean-targets) \
 251                         cscope gtags TAGS tags help% %docs check% coccicheck \
 252                         $(version_h) headers_% archheaders archscripts \
 253                         %asm-generic kernelversion %src-pkg
 254no-sync-config-targets := $(no-dot-config-targets) install %install \
 255                           kernelrelease
 256
 257config-targets  := 0
 258mixed-targets   := 0
 259dot-config      := 1
 260may-sync-config := 1
 261
 262ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
 263        ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
 264                dot-config := 0
 265        endif
 266endif
 267
 268ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
 269        ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
 270                may-sync-config := 0
 271        endif
 272endif
 273
 274ifneq ($(KBUILD_EXTMOD),)
 275        may-sync-config := 0
 276endif
 277
 278ifeq ($(KBUILD_EXTMOD),)
 279        ifneq ($(filter config %config,$(MAKECMDGOALS)),)
 280                config-targets := 1
 281                ifneq ($(words $(MAKECMDGOALS)),1)
 282                        mixed-targets := 1
 283                endif
 284        endif
 285endif
 286
 287# For "make -j clean all", "make -j mrproper defconfig all", etc.
 288ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
 289        ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
 290                mixed-targets := 1
 291        endif
 292endif
 293
 294# install and modules_install need also be processed one by one
 295ifneq ($(filter install,$(MAKECMDGOALS)),)
 296        ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
 297                mixed-targets := 1
 298        endif
 299endif
 300
 301ifeq ($(mixed-targets),1)
 302# ===========================================================================
 303# We're called with mixed targets (*config and build targets).
 304# Handle them one by one.
 305
 306PHONY += $(MAKECMDGOALS) __build_one_by_one
 307
 308$(filter-out __build_one_by_one, $(MAKECMDGOALS)): __build_one_by_one
 309        @:
 310
 311__build_one_by_one:
 312        $(Q)set -e; \
 313        for i in $(MAKECMDGOALS); do \
 314                $(MAKE) -f $(srctree)/Makefile $$i; \
 315        done
 316
 317else
 318
 319include scripts/Kbuild.include
 320
 321# Read KERNELRELEASE from include/config/kernel.release (if it exists)
 322KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
 323KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
 324export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
 325
 326include scripts/subarch.include
 327
 328# Cross compiling and selecting different set of gcc/bin-utils
 329# ---------------------------------------------------------------------------
 330#
 331# When performing cross compilation for other architectures ARCH shall be set
 332# to the target architecture. (See arch/* for the possibilities).
 333# ARCH can be set during invocation of make:
 334# make ARCH=ia64
 335# Another way is to have ARCH set in the environment.
 336# The default ARCH is the host where make is executed.
 337
 338# CROSS_COMPILE specify the prefix used for all executables used
 339# during compilation. Only gcc and related bin-utils executables
 340# are prefixed with $(CROSS_COMPILE).
 341# CROSS_COMPILE can be set on the command line
 342# make CROSS_COMPILE=ia64-linux-
 343# Alternatively CROSS_COMPILE can be set in the environment.
 344# Default value for CROSS_COMPILE is not to prefix executables
 345# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
 346ARCH            ?= $(SUBARCH)
 347
 348# Architecture as present in compile.h
 349UTS_MACHINE     := $(ARCH)
 350SRCARCH         := $(ARCH)
 351
 352# Additional ARCH settings for x86
 353ifeq ($(ARCH),i386)
 354        SRCARCH := x86
 355endif
 356ifeq ($(ARCH),x86_64)
 357        SRCARCH := x86
 358endif
 359
 360# Additional ARCH settings for sparc
 361ifeq ($(ARCH),sparc32)
 362       SRCARCH := sparc
 363endif
 364ifeq ($(ARCH),sparc64)
 365       SRCARCH := sparc
 366endif
 367
 368# Additional ARCH settings for sh
 369ifeq ($(ARCH),sh64)
 370       SRCARCH := sh
 371endif
 372
 373KCONFIG_CONFIG  ?= .config
 374export KCONFIG_CONFIG
 375
 376# SHELL used by kbuild
 377CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
 378          else if [ -x /bin/bash ]; then echo /bin/bash; \
 379          else echo sh; fi ; fi)
 380
 381HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
 382HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
 383HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
 384
 385HOSTCC       = gcc
 386HOSTCXX      = g++
 387KBUILD_HOSTCFLAGS   := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 \
 388                -fomit-frame-pointer -std=gnu89 $(HOST_LFS_CFLAGS) \
 389                $(HOSTCFLAGS)
 390KBUILD_HOSTCXXFLAGS := -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
 391KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
 392KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
 393
 394# Make variables (CC, etc...)
 395AS              = $(CROSS_COMPILE)as
 396LD              = $(CROSS_COMPILE)ld
 397CC              = $(CROSS_COMPILE)gcc
 398CPP             = $(CC) -E
 399AR              = $(CROSS_COMPILE)ar
 400NM              = $(CROSS_COMPILE)nm
 401STRIP           = $(CROSS_COMPILE)strip
 402OBJCOPY         = $(CROSS_COMPILE)objcopy
 403OBJDUMP         = $(CROSS_COMPILE)objdump
 404LEX             = flex
 405YACC            = bison
 406AWK             = awk
 407INSTALLKERNEL  := installkernel
 408DEPMOD          = /sbin/depmod
 409PERL            = perl
 410PYTHON          = python
 411PYTHON2         = python2
 412PYTHON3         = python3
 413CHECK           = sparse
 414
 415CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
 416                  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
 417NOSTDINC_FLAGS :=
 418CFLAGS_MODULE   =
 419AFLAGS_MODULE   =
 420LDFLAGS_MODULE  =
 421CFLAGS_KERNEL   =
 422AFLAGS_KERNEL   =
 423LDFLAGS_vmlinux =
 424
 425# Use USERINCLUDE when you must reference the UAPI directories only.
 426USERINCLUDE    := \
 427                -I$(srctree)/arch/$(SRCARCH)/include/uapi \
 428                -I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
 429                -I$(srctree)/include/uapi \
 430                -I$(objtree)/include/generated/uapi \
 431                -include $(srctree)/include/linux/kconfig.h
 432
 433# Use LINUXINCLUDE when you must reference the include/ directory.
 434# Needed to be compatible with the O= option
 435LINUXINCLUDE    := \
 436                -I$(srctree)/arch/$(SRCARCH)/include \
 437                -I$(objtree)/arch/$(SRCARCH)/include/generated \
 438                $(if $(KBUILD_SRC), -I$(srctree)/include) \
 439                -I$(objtree)/include \
 440                $(USERINCLUDE)
 441
 442KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
 443KBUILD_CFLAGS   := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
 444                   -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
 445                   -Werror=implicit-function-declaration -Werror=implicit-int \
 446                   -Wno-format-security \
 447                   -std=gnu89
 448KBUILD_CPPFLAGS := -D__KERNEL__
 449KBUILD_AFLAGS_KERNEL :=
 450KBUILD_CFLAGS_KERNEL :=
 451KBUILD_AFLAGS_MODULE  := -DMODULE
 452KBUILD_CFLAGS_MODULE  := -DMODULE
 453KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
 454KBUILD_LDFLAGS :=
 455GCC_PLUGINS_CFLAGS :=
 456
 457export ARCH SRCARCH CONFIG_SHELL HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE AS LD CC
 458export CPP AR NM STRIP OBJCOPY OBJDUMP KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS
 459export MAKE LEX YACC AWK INSTALLKERNEL PERL PYTHON PYTHON2 PYTHON3 UTS_MACHINE
 460export HOSTCXX KBUILD_HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
 461
 462export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
 463export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
 464export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN
 465export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
 466export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
 467export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
 468export KBUILD_ARFLAGS
 469
 470# When compiling out-of-tree modules, put MODVERDIR in the module
 471# tree rather than in the kernel tree. The kernel tree might
 472# even be read-only.
 473export MODVERDIR := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_versions
 474
 475# Files to ignore in find ... statements
 476
 477export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
 478                          -name CVS -o -name .pc -o -name .hg -o -name .git \) \
 479                          -prune -o
 480export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
 481                         --exclude CVS --exclude .pc --exclude .hg --exclude .git
 482
 483# ===========================================================================
 484# Rules shared between *config targets and build targets
 485
 486# Basic helpers built in scripts/basic/
 487PHONY += scripts_basic
 488scripts_basic:
 489        $(Q)$(MAKE) $(build)=scripts/basic
 490        $(Q)rm -f .tmp_quiet_recordmcount
 491
 492PHONY += outputmakefile
 493# outputmakefile generates a Makefile in the output directory, if using a
 494# separate output directory. This allows convenient use of make in the
 495# output directory.
 496# At the same time when output Makefile generated, generate .gitignore to
 497# ignore whole output directory
 498outputmakefile:
 499ifneq ($(KBUILD_SRC),)
 500        $(Q)ln -fsn $(srctree) source
 501        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile $(srctree)
 502        $(Q)test -e .gitignore || \
 503        { echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
 504endif
 505
 506ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),)
 507ifneq ($(CROSS_COMPILE),)
 508CLANG_FLAGS     := --target=$(notdir $(CROSS_COMPILE:%-=%))
 509GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
 510CLANG_FLAGS     += --prefix=$(GCC_TOOLCHAIN_DIR)
 511GCC_TOOLCHAIN   := $(realpath $(GCC_TOOLCHAIN_DIR)/..)
 512endif
 513ifneq ($(GCC_TOOLCHAIN),)
 514CLANG_FLAGS     += --gcc-toolchain=$(GCC_TOOLCHAIN)
 515endif
 516CLANG_FLAGS     += -no-integrated-as
 517KBUILD_CFLAGS   += $(CLANG_FLAGS)
 518KBUILD_AFLAGS   += $(CLANG_FLAGS)
 519export CLANG_FLAGS
 520endif
 521
 522RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
 523RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
 524RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
 525RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
 526RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
 527RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
 528export RETPOLINE_CFLAGS
 529export RETPOLINE_VDSO_CFLAGS
 530
 531# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
 532# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
 533# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
 534# and from include/config/auto.conf.cmd to detect the compiler upgrade.
 535CC_VERSION_TEXT = $(shell $(CC) --version | head -n 1)
 536
 537ifeq ($(config-targets),1)
 538# ===========================================================================
 539# *config targets only - make sure prerequisites are updated, and descend
 540# in scripts/kconfig to make the *config target
 541
 542# Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
 543# KBUILD_DEFCONFIG may point out an alternative default configuration
 544# used for 'make defconfig'
 545include arch/$(SRCARCH)/Makefile
 546export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
 547
 548config: scripts_basic outputmakefile FORCE
 549        $(Q)$(MAKE) $(build)=scripts/kconfig $@
 550
 551%config: scripts_basic outputmakefile FORCE
 552        $(Q)$(MAKE) $(build)=scripts/kconfig $@
 553
 554else
 555# ===========================================================================
 556# Build targets only - this includes vmlinux, arch specific targets, clean
 557# targets and others. In general all targets except *config targets.
 558
 559# If building an external module we do not care about the all: rule
 560# but instead _all depend on modules
 561PHONY += all
 562ifeq ($(KBUILD_EXTMOD),)
 563_all: all
 564else
 565_all: modules
 566endif
 567
 568# Decide whether to build built-in, modular, or both.
 569# Normally, just do built-in.
 570
 571KBUILD_MODULES :=
 572KBUILD_BUILTIN := 1
 573
 574# If we have only "make modules", don't compile built-in objects.
 575# When we're building modules with modversions, we need to consider
 576# the built-in objects during the descend as well, in order to
 577# make sure the checksums are up to date before we record them.
 578
 579ifeq ($(MAKECMDGOALS),modules)
 580  KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
 581endif
 582
 583# If we have "make <whatever> modules", compile modules
 584# in addition to whatever we do anyway.
 585# Just "make" or "make all" shall build modules as well
 586
 587ifneq ($(filter all _all modules,$(MAKECMDGOALS)),)
 588  KBUILD_MODULES := 1
 589endif
 590
 591ifeq ($(MAKECMDGOALS),)
 592  KBUILD_MODULES := 1
 593endif
 594
 595export KBUILD_MODULES KBUILD_BUILTIN
 596
 597ifeq ($(KBUILD_EXTMOD),)
 598# Objects we will link into vmlinux / subdirs we need to visit
 599init-y          := init/
 600drivers-y       := drivers/ sound/
 601net-y           := net/
 602libs-y          := lib/
 603core-y          := usr/
 604virt-y          := virt/
 605endif # KBUILD_EXTMOD
 606
 607ifeq ($(dot-config),1)
 608include include/config/auto.conf
 609endif
 610
 611# The all: target is the default when no target is given on the
 612# command line.
 613# This allow a user to issue only 'make' to build a kernel including modules
 614# Defaults to vmlinux, but the arch makefile usually adds further targets
 615all: vmlinux
 616
 617CFLAGS_GCOV     := -fprofile-arcs -ftest-coverage \
 618        $(call cc-option,-fno-tree-loop-im) \
 619        $(call cc-disable-warning,maybe-uninitialized,)
 620export CFLAGS_GCOV
 621
 622# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
 623ifdef CONFIG_FUNCTION_TRACER
 624  CC_FLAGS_FTRACE := -pg
 625endif
 626
 627# The arch Makefile can set ARCH_{CPP,A,C}FLAGS to override the default
 628# values of the respective KBUILD_* variables
 629ARCH_CPPFLAGS :=
 630ARCH_AFLAGS :=
 631ARCH_CFLAGS :=
 632include arch/$(SRCARCH)/Makefile
 633
 634ifeq ($(dot-config),1)
 635ifeq ($(may-sync-config),1)
 636# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
 637# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
 638# because some architectures define CROSS_COMPILE there.
 639-include include/config/auto.conf.cmd
 640
 641$(KCONFIG_CONFIG):
 642        @echo >&2 '***'
 643        @echo >&2 '*** Configuration file "$@" not found!'
 644        @echo >&2 '***'
 645        @echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
 646        @echo >&2 '*** "make menuconfig" or "make xconfig").'
 647        @echo >&2 '***'
 648        @/bin/false
 649
 650# The actual configuration files used during the build are stored in
 651# include/generated/ and include/config/. Update them if .config is newer than
 652# include/config/auto.conf (which mirrors .config).
 653#
 654# This exploits the 'multi-target pattern rule' trick.
 655# The syncconfig should be executed only once to make all the targets.
 656%/auto.conf %/auto.conf.cmd %/tristate.conf: $(KCONFIG_CONFIG)
 657        $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
 658else
 659# External modules and some install targets need include/generated/autoconf.h
 660# and include/config/auto.conf but do not care if they are up-to-date.
 661# Use auto.conf to trigger the test
 662PHONY += include/config/auto.conf
 663
 664include/config/auto.conf:
 665        $(Q)test -e include/generated/autoconf.h -a -e $@ || (          \
 666        echo >&2;                                                       \
 667        echo >&2 "  ERROR: Kernel configuration is invalid.";           \
 668        echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
 669        echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";      \
 670        echo >&2 ;                                                      \
 671        /bin/false)
 672
 673endif # may-sync-config
 674endif # $(dot-config)
 675
 676KBUILD_CFLAGS   += $(call cc-option,-fno-delete-null-pointer-checks,)
 677KBUILD_CFLAGS   += $(call cc-disable-warning,frame-address,)
 678KBUILD_CFLAGS   += $(call cc-disable-warning, format-truncation)
 679KBUILD_CFLAGS   += $(call cc-disable-warning, format-overflow)
 680KBUILD_CFLAGS   += $(call cc-disable-warning, int-in-bool-context)
 681KBUILD_CFLAGS   += $(call cc-disable-warning, address-of-packed-member)
 682
 683ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
 684KBUILD_CFLAGS   += -Os
 685else
 686KBUILD_CFLAGS   += -O2
 687endif
 688
 689ifdef CONFIG_CC_DISABLE_WARN_MAYBE_UNINITIALIZED
 690KBUILD_CFLAGS   += -Wno-maybe-uninitialized
 691endif
 692
 693# Tell gcc to never replace conditional load with a non-conditional one
 694KBUILD_CFLAGS   += $(call cc-option,--param=allow-store-data-races=0)
 695
 696include scripts/Makefile.kcov
 697include scripts/Makefile.gcc-plugins
 698
 699ifdef CONFIG_READABLE_ASM
 700# Disable optimizations that make assembler listings hard to read.
 701# reorder blocks reorders the control in the function
 702# ipa clone creates specialized cloned functions
 703# partial inlining inlines only parts of functions
 704KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
 705                 $(call cc-option,-fno-ipa-cp-clone,) \
 706                 $(call cc-option,-fno-partial-inlining)
 707endif
 708
 709ifneq ($(CONFIG_FRAME_WARN),0)
 710KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
 711endif
 712
 713stackp-flags-$(CONFIG_CC_HAS_STACKPROTECTOR_NONE) := -fno-stack-protector
 714stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
 715stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
 716
 717KBUILD_CFLAGS += $(stackp-flags-y)
 718
 719ifdef CONFIG_CC_IS_CLANG
 720KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
 721KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier)
 722KBUILD_CFLAGS += $(call cc-disable-warning, gnu)
 723# Quiet clang warning: comparison of unsigned expression < 0 is always false
 724KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare)
 725# CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
 726# source of a reference will be _MergedGlobals and not on of the whitelisted names.
 727# See modpost pattern 2
 728KBUILD_CFLAGS += $(call cc-option, -mno-global-merge,)
 729KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior)
 730else
 731
 732# These warnings generated too much noise in a regular build.
 733# Use make W=1 to enable them (see scripts/Makefile.extrawarn)
 734KBUILD_CFLAGS += -Wno-unused-but-set-variable
 735endif
 736
 737KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
 738ifdef CONFIG_FRAME_POINTER
 739KBUILD_CFLAGS   += -fno-omit-frame-pointer -fno-optimize-sibling-calls
 740else
 741# Some targets (ARM with Thumb2, for example), can't be built with frame
 742# pointers.  For those, we don't have FUNCTION_TRACER automatically
 743# select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
 744# incompatible with -fomit-frame-pointer with current GCC, so we don't use
 745# -fomit-frame-pointer with FUNCTION_TRACER.
 746ifndef CONFIG_FUNCTION_TRACER
 747KBUILD_CFLAGS   += -fomit-frame-pointer
 748endif
 749endif
 750
 751DEBUG_CFLAGS    := $(call cc-option, -fno-var-tracking-assignments)
 752
 753ifdef CONFIG_DEBUG_INFO
 754ifdef CONFIG_DEBUG_INFO_SPLIT
 755DEBUG_CFLAGS    += -gsplit-dwarf
 756else
 757DEBUG_CFLAGS    += -g
 758endif
 759KBUILD_AFLAGS   += -Wa,-gdwarf-2
 760endif
 761ifdef CONFIG_DEBUG_INFO_DWARF4
 762DEBUG_CFLAGS    += -gdwarf-4
 763endif
 764
 765ifdef CONFIG_DEBUG_INFO_REDUCED
 766DEBUG_CFLAGS    += $(call cc-option, -femit-struct-debug-baseonly) \
 767                   $(call cc-option,-fno-var-tracking)
 768endif
 769
 770KBUILD_CFLAGS += $(DEBUG_CFLAGS)
 771export DEBUG_CFLAGS
 772
 773ifdef CONFIG_FUNCTION_TRACER
 774ifdef CONFIG_FTRACE_MCOUNT_RECORD
 775  # gcc 5 supports generating the mcount tables directly
 776  ifeq ($(call cc-option-yn,-mrecord-mcount),y)
 777    CC_FLAGS_FTRACE     += -mrecord-mcount
 778    export CC_USING_RECORD_MCOUNT := 1
 779  endif
 780  ifdef CONFIG_HAVE_NOP_MCOUNT
 781    ifeq ($(call cc-option-yn, -mnop-mcount),y)
 782      CC_FLAGS_FTRACE   += -mnop-mcount
 783      CC_FLAGS_USING    += -DCC_USING_NOP_MCOUNT
 784    endif
 785  endif
 786endif
 787ifdef CONFIG_HAVE_FENTRY
 788  ifeq ($(call cc-option-yn, -mfentry),y)
 789    CC_FLAGS_FTRACE     += -mfentry
 790    CC_FLAGS_USING      += -DCC_USING_FENTRY
 791  endif
 792endif
 793export CC_FLAGS_FTRACE
 794KBUILD_CFLAGS   += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
 795KBUILD_AFLAGS   += $(CC_FLAGS_USING)
 796ifdef CONFIG_DYNAMIC_FTRACE
 797        ifdef CONFIG_HAVE_C_RECORDMCOUNT
 798                BUILD_C_RECORDMCOUNT := y
 799                export BUILD_C_RECORDMCOUNT
 800        endif
 801endif
 802endif
 803
 804# We trigger additional mismatches with less inlining
 805ifdef CONFIG_DEBUG_SECTION_MISMATCH
 806KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
 807endif
 808
 809ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
 810KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
 811LDFLAGS_vmlinux += --gc-sections
 812endif
 813
 814# arch Makefile may override CC so keep this after arch Makefile is included
 815NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
 816
 817# warn about C99 declaration after statement
 818KBUILD_CFLAGS += -Wdeclaration-after-statement
 819
 820# Variable Length Arrays (VLAs) should not be used anywhere in the kernel
 821KBUILD_CFLAGS += $(call cc-option,-Wvla)
 822
 823# disable pointer signed / unsigned warnings in gcc 4.0
 824KBUILD_CFLAGS += -Wno-pointer-sign
 825
 826# disable stringop warnings in gcc 8+
 827KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
 828
 829# disable invalid "can't wrap" optimizations for signed / pointers
 830KBUILD_CFLAGS   += $(call cc-option,-fno-strict-overflow)
 831
 832# clang sets -fmerge-all-constants by default as optimization, but this
 833# is non-conforming behavior for C and in fact breaks the kernel, so we
 834# need to disable it here generally.
 835KBUILD_CFLAGS   += $(call cc-option,-fno-merge-all-constants)
 836
 837# for gcc -fno-merge-all-constants disables everything, but it is fine
 838# to have actual conforming behavior enabled.
 839KBUILD_CFLAGS   += $(call cc-option,-fmerge-constants)
 840
 841# Make sure -fstack-check isn't enabled (like gentoo apparently did)
 842KBUILD_CFLAGS  += $(call cc-option,-fno-stack-check,)
 843
 844# conserve stack if available
 845KBUILD_CFLAGS   += $(call cc-option,-fconserve-stack)
 846
 847# Prohibit date/time macros, which would make the build non-deterministic
 848KBUILD_CFLAGS   += $(call cc-option,-Werror=date-time)
 849
 850# enforce correct pointer usage
 851KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)
 852
 853# Require designated initializers for all marked structures
 854KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)
 855
 856# change __FILE__ to the relative path from the srctree
 857KBUILD_CFLAGS   += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
 858
 859# use the deterministic mode of AR if available
 860KBUILD_ARFLAGS := $(call ar-option,D)
 861
 862include scripts/Makefile.kasan
 863include scripts/Makefile.extrawarn
 864include scripts/Makefile.ubsan
 865
 866# Add any arch overrides and user supplied CPPFLAGS, AFLAGS and CFLAGS as the
 867# last assignments
 868KBUILD_CPPFLAGS += $(ARCH_CPPFLAGS) $(KCPPFLAGS)
 869KBUILD_AFLAGS   += $(ARCH_AFLAGS)   $(KAFLAGS)
 870KBUILD_CFLAGS   += $(ARCH_CFLAGS)   $(KCFLAGS)
 871
 872# Use --build-id when available.
 873LDFLAGS_BUILD_ID := $(call ld-option, --build-id)
 874KBUILD_LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID)
 875LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)
 876
 877ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
 878LDFLAGS_vmlinux += $(call ld-option, -X,)
 879endif
 880
 881# insure the checker run with the right endianness
 882CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
 883
 884# the checker needs the correct machine size
 885CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
 886
 887# Default kernel image to build when no specific target is given.
 888# KBUILD_IMAGE may be overruled on the command line or
 889# set in the environment
 890# Also any assignments in arch/$(ARCH)/Makefile take precedence over
 891# this default value
 892export KBUILD_IMAGE ?= vmlinux
 893
 894#
 895# INSTALL_PATH specifies where to place the updated kernel and system map
 896# images. Default is /boot, but you can set it to other values
 897export  INSTALL_PATH ?= /boot
 898
 899#
 900# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
 901# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
 902# an argument if needed. Otherwise it defaults to the kernel install path
 903#
 904export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
 905
 906#
 907# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
 908# relocations required by build roots.  This is not defined in the
 909# makefile but the argument can be passed to make if needed.
 910#
 911
 912MODLIB  = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
 913export MODLIB
 914
 915#
 916# INSTALL_MOD_STRIP, if defined, will cause modules to be
 917# stripped after they are installed.  If INSTALL_MOD_STRIP is '1', then
 918# the default option --strip-debug will be used.  Otherwise,
 919# INSTALL_MOD_STRIP value will be used as the options to the strip command.
 920
 921ifdef INSTALL_MOD_STRIP
 922ifeq ($(INSTALL_MOD_STRIP),1)
 923mod_strip_cmd = $(STRIP) --strip-debug
 924else
 925mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
 926endif # INSTALL_MOD_STRIP=1
 927else
 928mod_strip_cmd = true
 929endif # INSTALL_MOD_STRIP
 930export mod_strip_cmd
 931
 932# CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
 933# after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
 934# or CONFIG_MODULE_COMPRESS_XZ.
 935
 936mod_compress_cmd = true
 937ifdef CONFIG_MODULE_COMPRESS
 938  ifdef CONFIG_MODULE_COMPRESS_GZIP
 939    mod_compress_cmd = gzip -n -f
 940  endif # CONFIG_MODULE_COMPRESS_GZIP
 941  ifdef CONFIG_MODULE_COMPRESS_XZ
 942    mod_compress_cmd = xz -f
 943  endif # CONFIG_MODULE_COMPRESS_XZ
 944endif # CONFIG_MODULE_COMPRESS
 945export mod_compress_cmd
 946
 947ifdef CONFIG_MODULE_SIG_ALL
 948$(eval $(call config_filename,MODULE_SIG_KEY))
 949
 950mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
 951else
 952mod_sign_cmd = true
 953endif
 954export mod_sign_cmd
 955
 956HOST_LIBELF_LIBS = $(shell pkg-config libelf --libs 2>/dev/null || echo -lelf)
 957
 958ifdef CONFIG_STACK_VALIDATION
 959  has_libelf := $(call try-run,\
 960                echo "int main() {}" | $(HOSTCC) -xc -o /dev/null $(HOST_LIBELF_LIBS) -,1,0)
 961  ifeq ($(has_libelf),1)
 962    objtool_target := tools/objtool FORCE
 963  else
 964    SKIP_STACK_VALIDATION := 1
 965    export SKIP_STACK_VALIDATION
 966  endif
 967endif
 968
 969PHONY += prepare0
 970
 971ifeq ($(KBUILD_EXTMOD),)
 972core-y          += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
 973
 974vmlinux-dirs    := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
 975                     $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
 976                     $(net-y) $(net-m) $(libs-y) $(libs-m) $(virt-y)))
 977
 978vmlinux-alldirs := $(sort $(vmlinux-dirs) $(patsubst %/,%,$(filter %/, \
 979                     $(init-) $(core-) $(drivers-) $(net-) $(libs-) $(virt-))))
 980
 981init-y          := $(patsubst %/, %/built-in.a, $(init-y))
 982core-y          := $(patsubst %/, %/built-in.a, $(core-y))
 983drivers-y       := $(patsubst %/, %/built-in.a, $(drivers-y))
 984net-y           := $(patsubst %/, %/built-in.a, $(net-y))
 985libs-y1         := $(patsubst %/, %/lib.a, $(libs-y))
 986libs-y2         := $(patsubst %/, %/built-in.a, $(filter-out %.a, $(libs-y)))
 987virt-y          := $(patsubst %/, %/built-in.a, $(virt-y))
 988
 989# Externally visible symbols (used by link-vmlinux.sh)
 990export KBUILD_VMLINUX_OBJS := $(head-y) $(init-y) $(core-y) $(libs-y2) \
 991                              $(drivers-y) $(net-y) $(virt-y)
 992export KBUILD_VMLINUX_LIBS := $(libs-y1)
 993export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
 994export LDFLAGS_vmlinux
 995# used by scripts/package/Makefile
 996export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) arch Documentation include samples scripts tools)
 997
 998vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
 999
1000# Recurse until adjust_autoksyms.sh is satisfied
1001PHONY += autoksyms_recursive
1002autoksyms_recursive: $(vmlinux-deps)
1003ifdef CONFIG_TRIM_UNUSED_KSYMS
1004        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1005          "$(MAKE) -f $(srctree)/Makefile vmlinux"
1006endif
1007
1008# For the kernel to actually contain only the needed exported symbols,
1009# we have to build modules as well to determine what those symbols are.
1010# (this can be evaluated only once include/config/auto.conf has been included)
1011ifdef CONFIG_TRIM_UNUSED_KSYMS
1012  KBUILD_MODULES := 1
1013endif
1014
1015autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1016
1017$(autoksyms_h):
1018        $(Q)mkdir -p $(dir $@)
1019        $(Q)touch $@
1020
1021ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1022
1023# Final link of vmlinux with optional arch pass after final link
1024cmd_link-vmlinux =                                                 \
1025        $(CONFIG_SHELL) $< $(LD) $(KBUILD_LDFLAGS) $(LDFLAGS_vmlinux) ;    \
1026        $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1027
1028vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1029        +$(call if_changed,link-vmlinux)
1030
1031targets := vmlinux
1032
1033# Build samples along the rest of the kernel. This needs headers_install.
1034ifdef CONFIG_SAMPLES
1035vmlinux-dirs += samples
1036samples: headers_install
1037endif
1038
1039# The actual objects are generated when descending,
1040# make sure no implicit rule kicks in
1041$(sort $(vmlinux-deps)): $(vmlinux-dirs) ;
1042
1043# Handle descending into subdirectories listed in $(vmlinux-dirs)
1044# Preset locale variables to speed up the build process. Limit locale
1045# tweaks to this spot to avoid wrong language settings when running
1046# make menuconfig etc.
1047# Error messages still appears in the original language
1048
1049PHONY += $(vmlinux-dirs)
1050$(vmlinux-dirs): prepare
1051        $(Q)$(MAKE) $(build)=$@ need-builtin=1
1052
1053filechk_kernel.release = \
1054        echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1055
1056# Store (new) KERNELRELEASE string in include/config/kernel.release
1057include/config/kernel.release: $(srctree)/Makefile FORCE
1058        $(call filechk,kernel.release)
1059
1060# Additional helpers built in scripts/
1061# Carefully list dependencies so we do not try to build scripts twice
1062# in parallel
1063PHONY += scripts
1064scripts: scripts_basic scripts_dtc
1065        $(Q)$(MAKE) $(build)=$(@)
1066
1067# Things we need to do before we recursively start building the kernel
1068# or the modules are listed in "prepare".
1069# A multi level approach is used. prepareN is processed before prepareN-1.
1070# archprepare is used in arch Makefiles and when processed asm symlink,
1071# version.h and scripts_basic is processed / created.
1072
1073PHONY += prepare archprepare prepare1 prepare3
1074
1075# prepare3 is used to check if we are building in a separate output directory,
1076# and if so do:
1077# 1) Check that make has not been executed in the kernel src $(srctree)
1078prepare3: include/config/kernel.release
1079ifneq ($(KBUILD_SRC),)
1080        @$(kecho) '  Using $(srctree) as source for kernel'
1081        $(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \
1082                echo >&2 "  $(srctree) is not clean, please run 'make mrproper'"; \
1083                echo >&2 "  in the '$(srctree)' directory.";\
1084                /bin/false; \
1085        fi;
1086endif
1087
1088prepare1: prepare3 outputmakefile asm-generic $(version_h) $(autoksyms_h) \
1089                                                include/generated/utsrelease.h
1090        $(cmd_crmodverdir)
1091
1092archprepare: archheaders archscripts prepare1 scripts
1093
1094prepare0: archprepare
1095        $(Q)$(MAKE) $(build)=scripts/mod
1096        $(Q)$(MAKE) $(build)=.
1097
1098# All the preparing..
1099prepare: prepare0 prepare-objtool
1100
1101# Support for using generic headers in asm-generic
1102asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1103
1104PHONY += asm-generic uapi-asm-generic
1105asm-generic: uapi-asm-generic
1106        $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1107        generic=include/asm-generic
1108uapi-asm-generic:
1109        $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1110        generic=include/uapi/asm-generic
1111
1112PHONY += prepare-objtool
1113prepare-objtool: $(objtool_target)
1114ifeq ($(SKIP_STACK_VALIDATION),1)
1115ifdef CONFIG_UNWINDER_ORC
1116        @echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1117        @false
1118else
1119        @echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1120endif
1121endif
1122
1123# Generate some files
1124# ---------------------------------------------------------------------------
1125
1126# KERNELRELEASE can change from a few different places, meaning version.h
1127# needs to be updated, so this check is forced on all builds
1128
1129uts_len := 64
1130define filechk_utsrelease.h
1131        if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1132          echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1133          exit 1;                                                         \
1134        fi;                                                               \
1135        echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1136endef
1137
1138define filechk_version.h
1139        echo \#define LINUX_VERSION_CODE $(shell                         \
1140        expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1141        echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))'
1142endef
1143
1144$(version_h): FORCE
1145        $(call filechk,version.h)
1146        $(Q)rm -f $(old_version_h)
1147
1148include/generated/utsrelease.h: include/config/kernel.release FORCE
1149        $(call filechk,utsrelease.h)
1150
1151PHONY += headerdep
1152headerdep:
1153        $(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1154        $(srctree)/scripts/headerdep.pl -I$(srctree)/include
1155
1156# ---------------------------------------------------------------------------
1157# Kernel headers
1158
1159#Default location for installed headers
1160export INSTALL_HDR_PATH = $(objtree)/usr
1161
1162# If we do an all arch process set dst to include/arch-$(SRCARCH)
1163hdr-dst = $(if $(KBUILD_HEADERS), dst=include/arch-$(SRCARCH), dst=include)
1164
1165PHONY += archheaders archscripts
1166
1167PHONY += __headers
1168__headers: $(version_h) scripts_basic uapi-asm-generic archheaders archscripts
1169        $(Q)$(MAKE) $(build)=scripts build_unifdef
1170
1171PHONY += headers_install_all
1172headers_install_all:
1173        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh install
1174
1175PHONY += headers_install
1176headers_install: __headers
1177        $(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1178          $(error Headers not exportable for the $(SRCARCH) architecture))
1179        $(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include
1180        $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi $(hdr-dst)
1181
1182PHONY += headers_check_all
1183headers_check_all: headers_install_all
1184        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh check
1185
1186PHONY += headers_check
1187headers_check: headers_install
1188        $(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include HDRCHECK=1
1189        $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi $(hdr-dst) HDRCHECK=1
1190
1191ifdef CONFIG_HEADERS_CHECK
1192all: headers_check
1193endif
1194
1195# ---------------------------------------------------------------------------
1196# Kernel selftest
1197
1198PHONY += kselftest
1199kselftest:
1200        $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1201
1202PHONY += kselftest-clean
1203kselftest-clean:
1204        $(Q)$(MAKE) -C $(srctree)/tools/testing/selftests clean
1205
1206PHONY += kselftest-merge
1207kselftest-merge:
1208        $(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1209        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/kconfig/merge_config.sh \
1210                -m $(objtree)/.config \
1211                $(srctree)/tools/testing/selftests/*/config
1212        +$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1213
1214# ---------------------------------------------------------------------------
1215# Devicetree files
1216
1217ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1218dtstree := arch/$(SRCARCH)/boot/dts
1219endif
1220
1221ifneq ($(dtstree),)
1222
1223%.dtb: prepare3 scripts_dtc
1224        $(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1225
1226PHONY += dtbs dtbs_install dt_binding_check
1227dtbs dtbs_check: prepare3 scripts_dtc
1228        $(Q)$(MAKE) $(build)=$(dtstree)
1229
1230dtbs_check: export CHECK_DTBS=1
1231dtbs_check: dt_binding_check
1232
1233dtbs_install:
1234        $(Q)$(MAKE) $(dtbinst)=$(dtstree)
1235
1236ifdef CONFIG_OF_EARLY_FLATTREE
1237all: dtbs
1238endif
1239
1240endif
1241
1242PHONY += scripts_dtc
1243scripts_dtc: scripts_basic
1244        $(Q)$(MAKE) $(build)=scripts/dtc
1245
1246dt_binding_check: scripts_dtc
1247        $(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1248
1249# ---------------------------------------------------------------------------
1250# Modules
1251
1252ifdef CONFIG_MODULES
1253
1254# By default, build modules as well
1255
1256all: modules
1257
1258# Build modules
1259#
1260# A module can be listed more than once in obj-m resulting in
1261# duplicate lines in modules.order files.  Those are removed
1262# using awk while concatenating to the final file.
1263
1264PHONY += modules
1265modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux) modules.builtin
1266        $(Q)$(AWK) '!x[$$0]++' $(vmlinux-dirs:%=$(objtree)/%/modules.order) > $(objtree)/modules.order
1267        @$(kecho) '  Building modules, stage 2.';
1268        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1269
1270modules.builtin: $(vmlinux-dirs:%=%/modules.builtin)
1271        $(Q)$(AWK) '!x[$$0]++' $^ > $(objtree)/modules.builtin
1272
1273%/modules.builtin: include/config/auto.conf include/config/tristate.conf
1274        $(Q)$(MAKE) $(modbuiltin)=$*
1275
1276
1277# Target to prepare building external modules
1278PHONY += modules_prepare
1279modules_prepare: prepare
1280
1281# Target to install modules
1282PHONY += modules_install
1283modules_install: _modinst_ _modinst_post
1284
1285PHONY += _modinst_
1286_modinst_:
1287        @rm -rf $(MODLIB)/kernel
1288        @rm -f $(MODLIB)/source
1289        @mkdir -p $(MODLIB)/kernel
1290        @ln -s $(abspath $(srctree)) $(MODLIB)/source
1291        @if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
1292                rm -f $(MODLIB)/build ; \
1293                ln -s $(CURDIR) $(MODLIB)/build ; \
1294        fi
1295        @cp -f $(objtree)/modules.order $(MODLIB)/
1296        @cp -f $(objtree)/modules.builtin $(MODLIB)/
1297        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1298
1299# This depmod is only for convenience to give the initial
1300# boot a modules.dep even before / is mounted read-write.  However the
1301# boot script depmod is the master version.
1302PHONY += _modinst_post
1303_modinst_post: _modinst_
1304        $(call cmd,depmod)
1305
1306ifeq ($(CONFIG_MODULE_SIG), y)
1307PHONY += modules_sign
1308modules_sign:
1309        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1310endif
1311
1312else # CONFIG_MODULES
1313
1314# Modules not configured
1315# ---------------------------------------------------------------------------
1316
1317PHONY += modules modules_install
1318modules modules_install:
1319        @echo >&2
1320        @echo >&2 "The present kernel configuration has modules disabled."
1321        @echo >&2 "Type 'make config' and enable loadable module support."
1322        @echo >&2 "Then build a kernel with module support enabled."
1323        @echo >&2
1324        @exit 1
1325
1326endif # CONFIG_MODULES
1327
1328###
1329# Cleaning is done on three levels.
1330# make clean     Delete most generated files
1331#                Leave enough to build external modules
1332# make mrproper  Delete the current configuration, and all generated files
1333# make distclean Remove editor backup files, patch leftover files and the like
1334
1335# Directories & files removed with 'make clean'
1336CLEAN_DIRS  += $(MODVERDIR) include/ksym
1337
1338# Directories & files removed with 'make mrproper'
1339MRPROPER_DIRS  += include/config usr/include include/generated          \
1340                  arch/*/include/generated .tmp_objdiff
1341MRPROPER_FILES += .config .config.old .version \
1342                  Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS \
1343                  signing_key.pem signing_key.priv signing_key.x509     \
1344                  x509.genkey extra_certificates signing_key.x509.keyid \
1345                  signing_key.x509.signer vmlinux-gdb.py
1346
1347# clean - Delete most, but leave enough to build external modules
1348#
1349clean: rm-dirs  := $(CLEAN_DIRS)
1350clean: rm-files := $(CLEAN_FILES)
1351clean-dirs      := $(addprefix _clean_, . $(vmlinux-alldirs) Documentation samples)
1352
1353PHONY += $(clean-dirs) clean archclean vmlinuxclean
1354$(clean-dirs):
1355        $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1356
1357vmlinuxclean:
1358        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1359        $(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1360
1361clean: archclean vmlinuxclean
1362
1363# mrproper - Delete all generated files, including .config
1364#
1365mrproper: rm-dirs  := $(wildcard $(MRPROPER_DIRS))
1366mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1367mrproper-dirs      := $(addprefix _mrproper_,scripts)
1368
1369PHONY += $(mrproper-dirs) mrproper
1370$(mrproper-dirs):
1371        $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1372
1373mrproper: clean $(mrproper-dirs)
1374        $(call cmd,rmdirs)
1375        $(call cmd,rmfiles)
1376
1377# distclean
1378#
1379PHONY += distclean
1380
1381distclean: mrproper
1382        @find $(srctree) $(RCS_FIND_IGNORE) \
1383                \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1384                -o -name '*.bak' -o -name '#*#' -o -name '*%' \
1385                -o -name 'core' \) \
1386                -type f -print | xargs rm -f
1387
1388
1389# Packaging of the kernel to various formats
1390# ---------------------------------------------------------------------------
1391package-dir     := scripts/package
1392
1393%src-pkg: FORCE
1394        $(Q)$(MAKE) $(build)=$(package-dir) $@
1395%pkg: include/config/kernel.release FORCE
1396        $(Q)$(MAKE) $(build)=$(package-dir) $@
1397
1398
1399# Brief documentation of the typical targets used
1400# ---------------------------------------------------------------------------
1401
1402boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1403boards := $(sort $(notdir $(boards)))
1404board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1405board-dirs := $(sort $(notdir $(board-dirs:/=)))
1406
1407PHONY += help
1408help:
1409        @echo  'Cleaning targets:'
1410        @echo  '  clean           - Remove most generated files but keep the config and'
1411        @echo  '                    enough build support to build external modules'
1412        @echo  '  mrproper        - Remove all generated files + config + various backup files'
1413        @echo  '  distclean       - mrproper + remove editor backup and patch files'
1414        @echo  ''
1415        @echo  'Configuration targets:'
1416        @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1417        @echo  ''
1418        @echo  'Other generic targets:'
1419        @echo  '  all             - Build all targets marked with [*]'
1420        @echo  '* vmlinux         - Build the bare kernel'
1421        @echo  '* modules         - Build all modules'
1422        @echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1423        @echo  '  dir/            - Build all files in dir and below'
1424        @echo  '  dir/file.[ois]  - Build specified target only'
1425        @echo  '  dir/file.ll     - Build the LLVM assembly file'
1426        @echo  '                    (requires compiler support for LLVM assembly generation)'
1427        @echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1428        @echo  '                    (requires a recent binutils and recent build (System.map))'
1429        @echo  '  dir/file.ko     - Build module including final link'
1430        @echo  '  modules_prepare - Set up for building external modules'
1431        @echo  '  tags/TAGS       - Generate tags file for editors'
1432        @echo  '  cscope          - Generate cscope index'
1433        @echo  '  gtags           - Generate GNU GLOBAL index'
1434        @echo  '  kernelrelease   - Output the release version string (use with make -s)'
1435        @echo  '  kernelversion   - Output the version stored in Makefile (use with make -s)'
1436        @echo  '  image_name      - Output the image name (use with make -s)'
1437        @echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1438         echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1439         echo  ''
1440        @echo  'Static analysers:'
1441        @echo  '  checkstack      - Generate a list of stack hogs'
1442        @echo  '  namespacecheck  - Name space analysis on compiled kernel'
1443        @echo  '  versioncheck    - Sanity check on version.h usage'
1444        @echo  '  includecheck    - Check for duplicate included header files'
1445        @echo  '  export_report   - List the usages of all exported symbols'
1446        @echo  '  headers_check   - Sanity check on exported headers'
1447        @echo  '  headerdep       - Detect inclusion cycles in headers'
1448        @echo  '  coccicheck      - Check with Coccinelle'
1449        @echo  ''
1450        @echo  'Kernel selftest:'
1451        @echo  '  kselftest       - Build and run kernel selftest (run as root)'
1452        @echo  '                    Build, install, and boot kernel before'
1453        @echo  '                    running kselftest on it'
1454        @echo  '  kselftest-clean - Remove all generated kselftest files'
1455        @echo  '  kselftest-merge - Merge all the config dependencies of kselftest to existing'
1456        @echo  '                    .config.'
1457        @echo  ''
1458        @$(if $(dtstree), \
1459                echo 'Devicetree:'; \
1460                echo '* dtbs            - Build device tree blobs for enabled boards'; \
1461                echo '  dtbs_install    - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1462                echo '')
1463
1464        @echo 'Userspace tools targets:'
1465        @echo '  use "make tools/help"'
1466        @echo '  or  "cd tools; make help"'
1467        @echo  ''
1468        @echo  'Kernel packaging:'
1469        @$(MAKE) $(build)=$(package-dir) help
1470        @echo  ''
1471        @echo  'Documentation targets:'
1472        @$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1473        @echo  ''
1474        @echo  'Architecture specific targets ($(SRCARCH)):'
1475        @$(if $(archhelp),$(archhelp),\
1476                echo '  No architecture specific help defined for $(SRCARCH)')
1477        @echo  ''
1478        @$(if $(boards), \
1479                $(foreach b, $(boards), \
1480                printf "  %-24s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1481                echo '')
1482        @$(if $(board-dirs), \
1483                $(foreach b, $(board-dirs), \
1484                printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1485                printf "  %-16s - Show all of the above\\n" help-boards; \
1486                echo '')
1487
1488        @echo  '  make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1489        @echo  '  make V=2   [targets] 2 => give reason for rebuild of target'
1490        @echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1491        @echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK (sparse by default)'
1492        @echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1493        @echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1494        @echo  '  make W=n   [targets] Enable extra gcc checks, n=1,2,3 where'
1495        @echo  '                1: warnings which may be relevant and do not occur too often'
1496        @echo  '                2: warnings which occur quite often but may still be relevant'
1497        @echo  '                3: more obscure warnings, can most likely be ignored'
1498        @echo  '                Multiple levels can be combined with W=12 or W=123'
1499        @echo  ''
1500        @echo  'Execute "make" or "make all" to build all targets marked with [*] '
1501        @echo  'For further info see the ./README file'
1502
1503
1504help-board-dirs := $(addprefix help-,$(board-dirs))
1505
1506help-boards: $(help-board-dirs)
1507
1508boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1509
1510$(help-board-dirs): help-%:
1511        @echo  'Architecture specific targets ($(SRCARCH) $*):'
1512        @$(if $(boards-per-dir), \
1513                $(foreach b, $(boards-per-dir), \
1514                printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1515                echo '')
1516
1517
1518# Documentation targets
1519# ---------------------------------------------------------------------------
1520DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1521               linkcheckdocs dochelp refcheckdocs
1522PHONY += $(DOC_TARGETS)
1523$(DOC_TARGETS): scripts_basic FORCE
1524        $(Q)$(MAKE) $(build)=Documentation $@
1525
1526# Misc
1527# ---------------------------------------------------------------------------
1528
1529PHONY += scripts_gdb
1530scripts_gdb: prepare
1531        $(Q)$(MAKE) $(build)=scripts/gdb
1532        $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1533
1534ifdef CONFIG_GDB_SCRIPTS
1535all: scripts_gdb
1536endif
1537
1538else # KBUILD_EXTMOD
1539
1540###
1541# External module support.
1542# When building external modules the kernel used as basis is considered
1543# read-only, and no consistency checks are made and the make
1544# system is not used on the basis kernel. If updates are required
1545# in the basis kernel ordinary make commands (without M=...) must
1546# be used.
1547#
1548# The following are the only valid targets when building external
1549# modules.
1550# make M=dir clean     Delete all automatically generated files
1551# make M=dir modules   Make all modules in specified dir
1552# make M=dir           Same as 'make M=dir modules'
1553# make M=dir modules_install
1554#                      Install the modules built in the module directory
1555#                      Assumes install directory is already created
1556
1557# We are always building modules
1558KBUILD_MODULES := 1
1559
1560PHONY += $(objtree)/Module.symvers
1561$(objtree)/Module.symvers:
1562        @test -e $(objtree)/Module.symvers || ( \
1563        echo; \
1564        echo "  WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1565        echo "           is missing; modules will have no dependencies and modversions."; \
1566        echo )
1567
1568module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
1569PHONY += $(module-dirs) modules
1570$(module-dirs): prepare $(objtree)/Module.symvers
1571        $(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@)
1572
1573modules: $(module-dirs)
1574        @$(kecho) '  Building modules, stage 2.';
1575        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1576
1577PHONY += modules_install
1578modules_install: _emodinst_ _emodinst_post
1579
1580install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1581PHONY += _emodinst_
1582_emodinst_:
1583        $(Q)mkdir -p $(MODLIB)/$(install-dir)
1584        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1585
1586PHONY += _emodinst_post
1587_emodinst_post: _emodinst_
1588        $(call cmd,depmod)
1589
1590clean-dirs := $(addprefix _clean_,$(KBUILD_EXTMOD))
1591
1592PHONY += $(clean-dirs) clean
1593$(clean-dirs):
1594        $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1595
1596clean:  rm-dirs := $(MODVERDIR)
1597clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers
1598
1599PHONY += help
1600help:
1601        @echo  '  Building external modules.'
1602        @echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1603        @echo  ''
1604        @echo  '  modules         - default target, build the module(s)'
1605        @echo  '  modules_install - install the module'
1606        @echo  '  clean           - remove generated files in module directory only'
1607        @echo  ''
1608
1609PHONY += prepare
1610prepare:
1611        $(cmd_crmodverdir)
1612endif # KBUILD_EXTMOD
1613
1614clean: $(clean-dirs)
1615        $(call cmd,rmdirs)
1616        $(call cmd,rmfiles)
1617        @find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1618                \( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1619                -o -name '*.ko.*' \
1620                -o -name '*.dtb' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1621                -o -name '*.dwo' -o -name '*.lst' \
1622                -o -name '*.su'  \
1623                -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1624                -o -name '*.lex.c' -o -name '*.tab.[ch]' \
1625                -o -name '*.asn1.[ch]' \
1626                -o -name '*.symtypes' -o -name 'modules.order' \
1627                -o -name modules.builtin -o -name '.tmp_*.o.*' \
1628                -o -name '*.c.[012]*.*' \
1629                -o -name '*.ll' \
1630                -o -name '*.gcno' \) -type f -print | xargs rm -f
1631
1632# Generate tags for editors
1633# ---------------------------------------------------------------------------
1634quiet_cmd_tags = GEN     $@
1635      cmd_tags = $(CONFIG_SHELL) $(srctree)/scripts/tags.sh $@
1636
1637tags TAGS cscope gtags: FORCE
1638        $(call cmd,tags)
1639
1640# Scripts to check various things for consistency
1641# ---------------------------------------------------------------------------
1642
1643PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1644
1645includecheck:
1646        find $(srctree)/* $(RCS_FIND_IGNORE) \
1647                -name '*.[hcS]' -type f -print | sort \
1648                | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1649
1650versioncheck:
1651        find $(srctree)/* $(RCS_FIND_IGNORE) \
1652                -name '*.[hcS]' -type f -print | sort \
1653                | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1654
1655coccicheck:
1656        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/$@
1657
1658namespacecheck:
1659        $(PERL) $(srctree)/scripts/namespace.pl
1660
1661export_report:
1662        $(PERL) $(srctree)/scripts/export_report.pl
1663
1664PHONY += checkstack kernelrelease kernelversion image_name
1665
1666# UML needs a little special treatment here.  It wants to use the host
1667# toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
1668# else wants $(ARCH), including people doing cross-builds, which means
1669# that $(SUBARCH) doesn't work here.
1670ifeq ($(ARCH), um)
1671CHECKSTACK_ARCH := $(SUBARCH)
1672else
1673CHECKSTACK_ARCH := $(ARCH)
1674endif
1675checkstack:
1676        $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1677        $(PERL) $(src)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1678
1679kernelrelease:
1680        @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1681
1682kernelversion:
1683        @echo $(KERNELVERSION)
1684
1685image_name:
1686        @echo $(KBUILD_IMAGE)
1687
1688# Clear a bunch of variables before executing the submake
1689
1690ifeq ($(quiet),silent_)
1691tools_silent=s
1692endif
1693
1694tools/: FORCE
1695        $(Q)mkdir -p $(objtree)/tools
1696        $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(src)/tools/
1697
1698tools/%: FORCE
1699        $(Q)mkdir -p $(objtree)/tools
1700        $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(src)/tools/ $*
1701
1702# Single targets
1703# ---------------------------------------------------------------------------
1704# Single targets are compatible with:
1705# - build with mixed source and output
1706# - build with separate output dir 'make O=...'
1707# - external modules
1708#
1709#  target-dir => where to store outputfile
1710#  build-dir  => directory in kernel source tree to use
1711
1712build-target = $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD)/)$@
1713build-dir = $(patsubst %/,%,$(dir $(build-target)))
1714
1715%.i: prepare FORCE
1716        $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1717%.ll: prepare FORCE
1718        $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1719%.lst: prepare FORCE
1720        $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1721%.o: prepare FORCE
1722        $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1723%.s: prepare FORCE
1724        $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1725%.symtypes: prepare FORCE
1726        $(Q)$(MAKE) $(build)=$(build-dir) $(build-target)
1727%.ko: %.o
1728        $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1729
1730# Modules
1731PHONY += /
1732/: ./
1733
1734# Make sure the latest headers are built for Documentation
1735Documentation/ samples/: headers_install
1736%/: prepare FORCE
1737        $(Q)$(MAKE) KBUILD_MODULES=1 $(build)=$(build-dir)
1738
1739# FIXME Should go into a make.lib or something
1740# ===========================================================================
1741
1742quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN   $(wildcard $(rm-dirs)))
1743      cmd_rmdirs = rm -rf $(rm-dirs)
1744
1745quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
1746      cmd_rmfiles = rm -f $(rm-files)
1747
1748# Run depmod only if we have System.map and depmod is executable
1749quiet_cmd_depmod = DEPMOD  $(KERNELRELEASE)
1750      cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1751                   $(KERNELRELEASE)
1752
1753# Create temporary dir for module support files
1754# clean it up only when building all modules
1755cmd_crmodverdir = $(Q)mkdir -p $(MODVERDIR) \
1756                  $(if $(KBUILD_MODULES),; rm -f $(MODVERDIR)/*)
1757
1758# read saved command lines for existing targets
1759existing-targets := $(wildcard $(sort $(targets)))
1760
1761-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
1762
1763endif   # ifeq ($(config-targets),1)
1764endif   # ifeq ($(mixed-targets),1)
1765endif   # need-sub-make
1766
1767PHONY += FORCE
1768FORCE:
1769
1770# Declare the contents of the PHONY variable as phony.  We keep that
1771# information in a variable so we can use it in if_changed and friends.
1772.PHONY: $(PHONY)
1773