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32 results

super.c

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    • Miklos Szeredi's avatar
      8d3095f4
      ovl: default permissions · 8d3095f4
      Miklos Szeredi authored
      
      Add mount option "default_permissions" to alter the way permissions are
      calculated.
      
      Without this option and prior to this patch permissions were calculated by
      underlying lower or upper filesystem.
      
      With this option the permissions are calculated by overlayfs based on the
      file owner, group and mode bits.
      
      This has significance for example when a read-only exported NFS filesystem
      is used as a lower layer.  In this case the underlying NFS filesystem will
      reply with EROFS, in which case all we know is that the filesystem is
      read-only.  But that's not what we are interested in, we are interested in
      whether the access would be allowed if the filesystem wasn't read-only; the
      server doesn't tell us that, and would need updating at various levels,
      which doesn't seem practicable.
      
      Signed-off-by: default avatarMiklos Szeredi <miklos@szeredi.hu>
      8d3095f4
      History
      ovl: default permissions
      Miklos Szeredi authored
      
      Add mount option "default_permissions" to alter the way permissions are
      calculated.
      
      Without this option and prior to this patch permissions were calculated by
      underlying lower or upper filesystem.
      
      With this option the permissions are calculated by overlayfs based on the
      file owner, group and mode bits.
      
      This has significance for example when a read-only exported NFS filesystem
      is used as a lower layer.  In this case the underlying NFS filesystem will
      reply with EROFS, in which case all we know is that the filesystem is
      read-only.  But that's not what we are interested in, we are interested in
      whether the access would be allowed if the filesystem wasn't read-only; the
      server doesn't tell us that, and would need updating at various levels,
      which doesn't seem practicable.
      
      Signed-off-by: default avatarMiklos Szeredi <miklos@szeredi.hu>
    Makefile 60.42 KiB
    # SPDX-License-Identifier: GPL-2.0
    VERSION = 5
    PATCHLEVEL = 8
    SUBLEVEL = 0
    EXTRAVERSION = -rc6
    NAME = Kleptomaniac Octopus
    
    # *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.
    
    $(if $(filter __%, $(MAKECMDGOALS)), \
    	$(error targets prefixed with '__' are only for internal use))
    
    # That's our default target when none is given on the command line
    PHONY := __all
    __all:
    
    # We are using a recursive build, so we need to do a little thinking
    # to get the ordering right.
    #
    # Most importantly: sub-Makefiles should only ever modify files in
    # their own directory. If in some directory we have a dependency on
    # a file in another dir (which doesn't happen often, but it's often
    # unavoidable when linking the built-in.a targets which finally
    # turn into vmlinux), we will call a sub make in that other dir, and
    # after that we are sure that everything which is in that other dir
    # is now up to date.
    #
    # The only cases where we need to modify files which have global
    # effects are thus separated out and done before the recursive
    # descending is started. They are now explicitly listed as the
    # prepare rule.
    
    ifneq ($(sub_make_done),1)
    
    # Do not use make's built-in rules and variables
    # (this increases performance and avoids hard-to-debug behaviour)
    MAKEFLAGS += -rR
    
    # Avoid funny character set dependencies
    unexport LC_ALL
    LC_COLLATE=C
    LC_NUMERIC=C
    export LC_COLLATE LC_NUMERIC
    
    # Avoid interference with shell env settings
    unexport GREP_OPTIONS
    
    # 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.
    # If KBUILD_VERBOSE equals 2 then give the reason why each target is rebuilt.
    #
    # To put more focus on warnings, be less verbose as default
    # Use 'make V=1' to see the full commands
    
    ifeq ("$(origin V)", "command line")
      KBUILD_VERBOSE = $(V)
    endif
    ifndef KBUILD_VERBOSE
      KBUILD_VERBOSE = 0
    endif
    
    ifeq ($(KBUILD_VERBOSE),1)
      quiet =
      Q =
    else
      quiet=quiet_
      Q = @
    endif
    
    # If the user is running make -s (silent mode), suppress echoing of
    # commands
    
    ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
      quiet=silent_
    endif
    
    export quiet Q KBUILD_VERBOSE
    
    # Kbuild will save output files in the current working directory.
    # This does not need to match to the root of the kernel source tree.
    #
    # For example, you can do this:
    #
    #  cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
    #
    # If you want to save output files in a different location, there are
    # two syntaxes to specify it.
    #
    # 1) O=
    # Use "make O=dir/to/store/output/files/"
    #
    # 2) Set KBUILD_OUTPUT
    # Set the environment variable KBUILD_OUTPUT to point to the output directory.
    # export KBUILD_OUTPUT=dir/to/store/output/files/; make
    #
    # The O= assignment takes precedence over the KBUILD_OUTPUT environment
    # variable.
    
    # Do we want to change the working directory?
    ifeq ("$(origin O)", "command line")
      KBUILD_OUTPUT := $(O)
    endif
    
    ifneq ($(KBUILD_OUTPUT),)
    # Make's built-in functions such as $(abspath ...), $(realpath ...) cannot
    # expand a shell special character '~'. We use a somewhat tedious way here.
    abs_objtree := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) && pwd)
    $(if $(abs_objtree),, \
         $(error failed to create output directory "$(KBUILD_OUTPUT)"))
    
    # $(realpath ...) resolves symlinks
    abs_objtree := $(realpath $(abs_objtree))
    else
    abs_objtree := $(CURDIR)
    endif # ifneq ($(KBUILD_OUTPUT),)
    
    ifeq ($(abs_objtree),$(CURDIR))
    # Suppress "Entering directory ..." unless we are changing the work directory.
    MAKEFLAGS += --no-print-directory
    else
    need-sub-make := 1
    endif
    
    abs_srctree := $(realpath $(dir $(lastword $(MAKEFILE_LIST))))
    
    ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
    $(error source directory cannot contain spaces or colons)
    endif
    
    ifneq ($(abs_srctree),$(abs_objtree))
    # Look for make include files relative to root of kernel src
    #
    # This does not become effective immediately because MAKEFLAGS is re-parsed
    # once after the Makefile is read. We need to invoke sub-make.
    MAKEFLAGS += --include-dir=$(abs_srctree)
    need-sub-make := 1
    endif
    
    this-makefile := $(lastword $(MAKEFILE_LIST))
    
    ifneq ($(filter 3.%,$(MAKE_VERSION)),)
    # 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
    # We need to invoke sub-make to avoid implicit rules in the top Makefile.
    need-sub-make := 1
    # Cancel implicit rules for this Makefile.
    $(this-makefile): ;
    endif
    
    export abs_srctree abs_objtree
    export sub_make_done := 1
    
    ifeq ($(need-sub-make),1)
    
    PHONY += $(MAKECMDGOALS) __sub-make
    
    $(filter-out $(this-makefile), $(MAKECMDGOALS)) __all: __sub-make
    	@:
    
    # Invoke a second make in the output directory, passing relevant variables
    __sub-make:
    	$(Q)$(MAKE) -C $(abs_objtree) -f $(abs_srctree)/Makefile $(MAKECMDGOALS)
    
    endif # need-sub-make
    endif # sub_make_done
    
    # We process the rest of the Makefile if this is the final invocation of make
    ifeq ($(need-sub-make),)
    
    # 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
    
    # 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.
    #
    # See the file "Documentation/dev-tools/sparse.rst" for more details,
    # including where to get the "sparse" utility.
    
    ifeq ("$(origin C)", "command line")
      KBUILD_CHECKSRC = $(C)
    endif
    ifndef KBUILD_CHECKSRC
      KBUILD_CHECKSRC = 0
    endif
    
    # Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
    # directory of external module to build. Setting M= takes precedence.
    ifeq ("$(origin M)", "command line")
      KBUILD_EXTMOD := $(M)
    endif
    
    $(if $(word 2, $(KBUILD_EXTMOD)), \
    	$(error building multiple external modules is not supported))
    
    export KBUILD_CHECKSRC KBUILD_EXTMOD
    
    extmod-prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
    
    ifeq ($(abs_srctree),$(abs_objtree))
            # building in the source tree
            srctree := .
    	building_out_of_srctree :=
    else
            ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
                    # building in a subdirectory of the source tree
                    srctree := ..
            else
                    srctree := $(abs_srctree)
            endif
    	building_out_of_srctree := 1
    endif
    
    ifneq ($(KBUILD_ABS_SRCTREE),)
    srctree := $(abs_srctree)
    endif
    
    objtree		:= .
    VPATH		:= $(srctree)
    
    export building_out_of_srctree srctree objtree VPATH
    
    # 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
    
    clean-targets := %clean mrproper cleandocs
    no-dot-config-targets := $(clean-targets) \
    			 cscope gtags TAGS tags help% %docs check% coccicheck \
    			 $(version_h) headers headers_% archheaders archscripts \
    			 %asm-generic kernelversion %src-pkg dt_binding_check \
    			 outputmakefile
    no-sync-config-targets := $(no-dot-config-targets) install %install \
    			   kernelrelease
    single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
    
    config-build	:=
    mixed-build	:=
    need-config	:= 1
    may-sync-config	:= 1
    single-build	:=
    
    ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
    	ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
    		need-config :=
    	endif
    endif
    
    ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
    	ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
    		may-sync-config :=
    	endif
    endif
    
    ifneq ($(KBUILD_EXTMOD),)
    	may-sync-config :=
    endif
    
    ifeq ($(KBUILD_EXTMOD),)
            ifneq ($(filter config %config,$(MAKECMDGOALS)),)
    		config-build := 1
                    ifneq ($(words $(MAKECMDGOALS)),1)
    			mixed-build := 1
                    endif
            endif
    endif
    
    # We cannot build single targets and the others at the same time
    ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
    	single-build := 1
    	ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
    		mixed-build := 1
    	endif
    endif
    
    # For "make -j clean all", "make -j mrproper defconfig all", etc.
    ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
            ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
    		mixed-build := 1
            endif
    endif
    
    # install and modules_install need also be processed one by one
    ifneq ($(filter install,$(MAKECMDGOALS)),)
            ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
    		mixed-build := 1
            endif
    endif
    
    ifdef mixed-build
    # ===========================================================================
    # We're called with mixed targets (*config and build targets).
    # Handle them one by one.
    
    PHONY += $(MAKECMDGOALS) __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 # !mixed-build
    
    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
    
    include scripts/subarch.include
    
    # 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
    ARCH		?= $(SUBARCH)
    
    # Architecture as present in compile.h
    UTS_MACHINE 	:= $(ARCH)
    SRCARCH 	:= $(ARCH)
    
    # Additional ARCH settings for x86
    ifeq ($(ARCH),i386)
            SRCARCH := x86
    endif
    ifeq ($(ARCH),x86_64)
            SRCARCH := x86
    endif
    
    # Additional ARCH settings for sparc
    ifeq ($(ARCH),sparc32)
           SRCARCH := sparc
    endif
    ifeq ($(ARCH),sparc64)
           SRCARCH := sparc
    endif
    
    # Additional ARCH settings for sh
    ifeq ($(ARCH),sh64)
           SRCARCH := sh
    endif
    
    KCONFIG_CONFIG	?= .config
    export KCONFIG_CONFIG
    
    # Default file for 'make defconfig'. This may be overridden by arch-Makefile.
    export KBUILD_DEFCONFIG := defconfig
    
    # SHELL used by kbuild
    CONFIG_SHELL := sh
    
    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)
    
    ifneq ($(LLVM),)
    HOSTCC	= clang
    HOSTCXX	= clang++
    else
    HOSTCC	= gcc
    HOSTCXX	= g++
    endif
    
    export KBUILD_USERCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
    			      -O2 -fomit-frame-pointer -std=gnu89
    export KBUILD_USERLDFLAGS :=
    
    KBUILD_HOSTCFLAGS   := $(KBUILD_USERCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
    KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
    KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
    KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
    
    # Make variables (CC, etc...)
    CPP		= $(CC) -E
    ifneq ($(LLVM),)
    CC		= clang
    LD		= ld.lld
    AR		= llvm-ar
    NM		= llvm-nm
    OBJCOPY		= llvm-objcopy
    OBJDUMP		= llvm-objdump
    READELF		= llvm-readelf
    OBJSIZE		= llvm-size
    STRIP		= llvm-strip
    else
    CC		= $(CROSS_COMPILE)gcc
    LD		= $(CROSS_COMPILE)ld
    AR		= $(CROSS_COMPILE)ar
    NM		= $(CROSS_COMPILE)nm
    OBJCOPY		= $(CROSS_COMPILE)objcopy
    OBJDUMP		= $(CROSS_COMPILE)objdump
    READELF		= $(CROSS_COMPILE)readelf
    OBJSIZE		= $(CROSS_COMPILE)size
    STRIP		= $(CROSS_COMPILE)strip
    endif
    PAHOLE		= pahole
    LEX		= flex
    YACC		= bison
    AWK		= awk
    INSTALLKERNEL  := installkernel
    DEPMOD		= /sbin/depmod
    PERL		= perl
    PYTHON		= python
    PYTHON3		= python3
    CHECK		= sparse
    BASH		= bash
    KGZIP		= gzip
    KBZIP2		= bzip2
    KLZOP		= lzop
    LZMA		= lzma
    LZ4		= lz4c
    XZ		= xz
    
    CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
    		  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
    NOSTDINC_FLAGS :=
    CFLAGS_MODULE   =
    AFLAGS_MODULE   =
    LDFLAGS_MODULE  =
    CFLAGS_KERNEL	=
    AFLAGS_KERNEL	=
    LDFLAGS_vmlinux =
    
    # Use USERINCLUDE when you must reference the UAPI directories only.
    USERINCLUDE    := \
    		-I$(srctree)/arch/$(SRCARCH)/include/uapi \
    		-I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
    		-I$(srctree)/include/uapi \
    		-I$(objtree)/include/generated/uapi \
                    -include $(srctree)/include/linux/kconfig.h
    
    # Use LINUXINCLUDE when you must reference the include/ directory.
    # Needed to be compatible with the O= option
    LINUXINCLUDE    := \
    		-I$(srctree)/arch/$(SRCARCH)/include \
    		-I$(objtree)/arch/$(SRCARCH)/include/generated \
    		$(if $(building_out_of_srctree),-I$(srctree)/include) \
    		-I$(objtree)/include \
    		$(USERINCLUDE)
    
    KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
    KBUILD_CFLAGS   := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
    		   -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
    		   -Werror=implicit-function-declaration -Werror=implicit-int \
    		   -Wno-format-security \
    		   -std=gnu89
    KBUILD_CPPFLAGS := -D__KERNEL__
    KBUILD_AFLAGS_KERNEL :=
    KBUILD_CFLAGS_KERNEL :=
    KBUILD_AFLAGS_MODULE  := -DMODULE
    KBUILD_CFLAGS_MODULE  := -DMODULE
    KBUILD_LDFLAGS_MODULE :=
    export KBUILD_LDS_MODULE := $(srctree)/scripts/module-common.lds
    KBUILD_LDFLAGS :=
    GCC_PLUGINS_CFLAGS :=
    CLANG_FLAGS :=
    
    export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC
    export CPP AR NM STRIP OBJCOPY OBJDUMP OBJSIZE READELF PAHOLE LEX YACC AWK INSTALLKERNEL
    export PERL PYTHON PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
    export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ
    export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
    
    export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
    export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
    export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN CFLAGS_KCSAN
    export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
    export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
    export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
    
    # Files to ignore in find ... statements
    
    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
    export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
    			 --exclude CVS --exclude .pc --exclude .hg --exclude .git
    
    # ===========================================================================
    # Rules shared between *config targets and build targets
    
    # Basic helpers built in scripts/basic/
    PHONY += scripts_basic
    scripts_basic:
    	$(Q)$(MAKE) $(build)=scripts/basic
    	$(Q)rm -f .tmp_quiet_recordmcount
    
    PHONY += outputmakefile
    # Before starting out-of-tree build, make sure the source tree is clean.
    # outputmakefile generates a Makefile in the output directory, if using a
    # separate output directory. This allows convenient use of make in the
    # output directory.
    # At the same time when output Makefile generated, generate .gitignore to
    # ignore whole output directory
    outputmakefile:
    ifdef building_out_of_srctree
    	$(Q)if [ -f $(srctree)/.config -o \
    		 -d $(srctree)/include/config -o \
    		 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
    		echo >&2 "***"; \
    		echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
    		echo >&2 "*** in $(abs_srctree)";\
    		echo >&2 "***"; \
    		false; \
    	fi
    	$(Q)ln -fsn $(srctree) source
    	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile $(srctree)
    	$(Q)test -e .gitignore || \
    	{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
    endif
    
    ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),)
    ifneq ($(CROSS_COMPILE),)
    CLANG_FLAGS	+= --target=$(notdir $(CROSS_COMPILE:%-=%))
    GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
    CLANG_FLAGS	+= --prefix=$(GCC_TOOLCHAIN_DIR)
    GCC_TOOLCHAIN	:= $(realpath $(GCC_TOOLCHAIN_DIR)/..)
    endif
    ifneq ($(GCC_TOOLCHAIN),)
    CLANG_FLAGS	+= --gcc-toolchain=$(GCC_TOOLCHAIN)
    endif
    ifneq ($(LLVM_IAS),1)
    CLANG_FLAGS	+= -no-integrated-as
    endif
    CLANG_FLAGS	+= -Werror=unknown-warning-option
    KBUILD_CFLAGS	+= $(CLANG_FLAGS)
    KBUILD_AFLAGS	+= $(CLANG_FLAGS)
    export CLANG_FLAGS
    endif
    
    # 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 2>/dev/null | head -n 1)
    
    ifdef config-build
    # ===========================================================================
    # *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'
    include arch/$(SRCARCH)/Makefile
    export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
    
    config: outputmakefile scripts_basic FORCE
    	$(Q)$(MAKE) $(build)=scripts/kconfig $@
    
    %config: outputmakefile scripts_basic FORCE
    	$(Q)$(MAKE) $(build)=scripts/kconfig $@
    
    else #!config-build
    # ===========================================================================
    # Build targets only - this includes vmlinux, arch specific targets, clean
    # targets and others. In general all targets except *config targets.
    
    # 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.
    ifeq ($(MAKECMDGOALS),modules)
      KBUILD_BUILTIN :=
    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 ($(filter all modules nsdeps,$(MAKECMDGOALS)),)
      KBUILD_MODULES := 1
    endif
    
    ifeq ($(MAKECMDGOALS),)
      KBUILD_MODULES := 1
    endif
    
    export KBUILD_MODULES KBUILD_BUILTIN
    
    ifdef need-config
    include include/config/auto.conf
    endif
    
    ifeq ($(KBUILD_EXTMOD),)
    # Objects we will link into vmlinux / subdirs we need to visit
    core-y		:= init/ usr/
    drivers-y	:= drivers/ sound/
    drivers-$(CONFIG_SAMPLES) += samples/
    drivers-y	+= net/ virt/
    libs-y		:= lib/
    endif # KBUILD_EXTMOD
    
    # 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,)
    export CFLAGS_GCOV
    
    # The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
    ifdef CONFIG_FUNCTION_TRACER
      CC_FLAGS_FTRACE := -pg
    endif
    
    RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
    RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
    RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
    RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
    RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
    RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
    export RETPOLINE_CFLAGS
    export RETPOLINE_VDSO_CFLAGS
    
    include arch/$(SRCARCH)/Makefile
    
    ifdef need-config
    ifdef may-sync-config
    # 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.
    include include/config/auto.conf.cmd
    
    $(KCONFIG_CONFIG):
    	@echo >&2 '***'
    	@echo >&2 '*** Configuration file "$@" not found!'
    	@echo >&2 '***'
    	@echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
    	@echo >&2 '*** "make menuconfig" or "make xconfig").'
    	@echo >&2 '***'
    	@/bin/false
    
    # 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).
    #
    # This exploits the 'multi-target pattern rule' trick.
    # The syncconfig should be executed only once to make all the targets.
    # (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
    %/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h: $(KCONFIG_CONFIG)
    	$(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
    else # !may-sync-config
    # 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
    PHONY += include/config/auto.conf
    
    include/config/auto.conf:
    	$(Q)test -e include/generated/autoconf.h -a -e $@ || (		\
    	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 ;							\
    	/bin/false)
    
    endif # may-sync-config
    endif # need-config
    
    KBUILD_CFLAGS	+= $(call cc-option,-fno-delete-null-pointer-checks,)
    KBUILD_CFLAGS	+= $(call cc-disable-warning,frame-address,)
    KBUILD_CFLAGS	+= $(call cc-disable-warning, format-truncation)
    KBUILD_CFLAGS	+= $(call cc-disable-warning, format-overflow)
    KBUILD_CFLAGS	+= $(call cc-disable-warning, address-of-packed-member)
    
    ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
    KBUILD_CFLAGS += -O2
    else ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3
    KBUILD_CFLAGS += -O3
    else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
    KBUILD_CFLAGS += -Os
    endif
    
    # Tell gcc to never replace conditional load with a non-conditional one
    KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
    KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
    
    include scripts/Makefile.kcov
    include scripts/Makefile.gcc-plugins
    
    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
    
    ifneq ($(CONFIG_FRAME_WARN),0)
    KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
    endif
    
    stackp-flags-$(CONFIG_CC_HAS_STACKPROTECTOR_NONE) := -fno-stack-protector
    stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
    stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
    
    KBUILD_CFLAGS += $(stackp-flags-y)
    
    ifdef CONFIG_CC_IS_CLANG
    KBUILD_CPPFLAGS += -Qunused-arguments
    KBUILD_CFLAGS += -Wno-format-invalid-specifier
    KBUILD_CFLAGS += -Wno-gnu
    # 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 += -mno-global-merge
    else
    
    # These warnings generated too much noise in a regular build.
    # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
    KBUILD_CFLAGS += -Wno-unused-but-set-variable
    
    # Warn about unmarked fall-throughs in switch statement.
    # Disabled for clang while comment to attribute conversion happens and
    # https://github.com/ClangBuiltLinux/linux/issues/636 is discussed.
    KBUILD_CFLAGS += $(call cc-option,-Wimplicit-fallthrough,)
    endif
    
    KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
    ifdef CONFIG_FRAME_POINTER
    KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
    else
    # 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
    KBUILD_CFLAGS	+= -fomit-frame-pointer
    endif
    endif
    
    # Initialize all stack variables with a pattern, if desired.
    ifdef CONFIG_INIT_STACK_ALL
    KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
    endif
    
    DEBUG_CFLAGS	:= $(call cc-option, -fno-var-tracking-assignments)
    
    ifdef CONFIG_DEBUG_INFO
    ifdef CONFIG_DEBUG_INFO_SPLIT
    DEBUG_CFLAGS	+= -gsplit-dwarf
    else
    DEBUG_CFLAGS	+= -g
    endif
    KBUILD_AFLAGS	+= -Wa,-gdwarf-2
    endif
    ifdef CONFIG_DEBUG_INFO_DWARF4
    DEBUG_CFLAGS	+= -gdwarf-4
    endif
    
    ifdef CONFIG_DEBUG_INFO_REDUCED
    DEBUG_CFLAGS	+= $(call cc-option, -femit-struct-debug-baseonly) \
    		   $(call cc-option,-fno-var-tracking)
    endif
    
    ifdef CONFIG_DEBUG_INFO_COMPRESSED
    DEBUG_CFLAGS	+= -gz=zlib
    KBUILD_AFLAGS	+= -gz=zlib
    KBUILD_LDFLAGS	+= --compress-debug-sections=zlib
    endif
    
    KBUILD_CFLAGS += $(DEBUG_CFLAGS)
    export DEBUG_CFLAGS
    
    ifdef CONFIG_FUNCTION_TRACER
    ifdef CONFIG_FTRACE_MCOUNT_RECORD
      # gcc 5 supports generating the mcount tables directly
      ifeq ($(call cc-option-yn,-mrecord-mcount),y)
        CC_FLAGS_FTRACE	+= -mrecord-mcount
        export CC_USING_RECORD_MCOUNT := 1
      endif
      ifdef CONFIG_HAVE_NOP_MCOUNT
        ifeq ($(call cc-option-yn, -mnop-mcount),y)
          CC_FLAGS_FTRACE	+= -mnop-mcount
          CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
        endif
      endif
    endif
    ifdef CONFIG_HAVE_FENTRY
      ifeq ($(call cc-option-yn, -mfentry),y)
        CC_FLAGS_FTRACE	+= -mfentry
        CC_FLAGS_USING	+= -DCC_USING_FENTRY
      endif
    endif
    export CC_FLAGS_FTRACE
    KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
    KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
    ifdef CONFIG_DYNAMIC_FTRACE
    	ifdef CONFIG_HAVE_C_RECORDMCOUNT
    		BUILD_C_RECORDMCOUNT := y
    		export BUILD_C_RECORDMCOUNT
    	endif
    endif
    endif
    
    # We trigger additional mismatches with less inlining
    ifdef CONFIG_DEBUG_SECTION_MISMATCH
    KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
    endif
    
    ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
    KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
    LDFLAGS_vmlinux += --gc-sections
    endif
    
    ifdef CONFIG_LIVEPATCH
    KBUILD_CFLAGS += $(call cc-option, -flive-patching=inline-clone)
    endif
    
    ifdef CONFIG_SHADOW_CALL_STACK
    CC_FLAGS_SCS	:= -fsanitize=shadow-call-stack
    KBUILD_CFLAGS	+= $(CC_FLAGS_SCS)
    export CC_FLAGS_SCS
    endif
    
    # arch Makefile may override CC so keep this after arch Makefile is included
    NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
    
    # warn about C99 declaration after statement
    KBUILD_CFLAGS += -Wdeclaration-after-statement
    
    # Variable Length Arrays (VLAs) should not be used anywhere in the kernel
    KBUILD_CFLAGS += -Wvla
    
    # disable pointer signed / unsigned warnings in gcc 4.0
    KBUILD_CFLAGS += -Wno-pointer-sign
    
    # disable stringop warnings in gcc 8+
    KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
    
    # We'll want to enable this eventually, but it's not going away for 5.7 at least
    KBUILD_CFLAGS += $(call cc-disable-warning, zero-length-bounds)
    KBUILD_CFLAGS += $(call cc-disable-warning, array-bounds)
    KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
    
    # Another good warning that we'll want to enable eventually
    KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
    
    # Enabled with W=2, disabled by default as noisy
    KBUILD_CFLAGS += $(call cc-disable-warning, maybe-uninitialized)
    
    # disable invalid "can't wrap" optimizations for signed / pointers
    KBUILD_CFLAGS	+= $(call cc-option,-fno-strict-overflow)
    
    # 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)
    
    # Make sure -fstack-check isn't enabled (like gentoo apparently did)
    KBUILD_CFLAGS  += $(call cc-option,-fno-stack-check,)
    
    # conserve stack if available
    KBUILD_CFLAGS   += $(call cc-option,-fconserve-stack)
    
    # Prohibit date/time macros, which would make the build non-deterministic
    KBUILD_CFLAGS   += $(call cc-option,-Werror=date-time)
    
    # enforce correct pointer usage
    KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)
    
    # Require designated initializers for all marked structures
    KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)
    
    # change __FILE__ to the relative path from the srctree
    KBUILD_CFLAGS	+= $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
    
    # ensure -fcf-protection is disabled when using retpoline as it is
    # incompatible with -mindirect-branch=thunk-extern
    ifdef CONFIG_RETPOLINE
    KBUILD_CFLAGS += $(call cc-option,-fcf-protection=none)
    endif
    
    include scripts/Makefile.kasan
    include scripts/Makefile.extrawarn
    include scripts/Makefile.ubsan
    include scripts/Makefile.kcsan
    
    # Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
    KBUILD_CPPFLAGS += $(KCPPFLAGS)
    KBUILD_AFLAGS   += $(KAFLAGS)
    KBUILD_CFLAGS   += $(KCFLAGS)
    
    KBUILD_LDFLAGS_MODULE += --build-id
    LDFLAGS_vmlinux += --build-id
    
    ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
    LDFLAGS_vmlinux	+= $(call ld-option, -X,)
    endif
    
    ifeq ($(CONFIG_RELR),y)
    LDFLAGS_vmlinux	+= --pack-dyn-relocs=relr
    endif
    
    # Align the bit size of userspace programs with the kernel
    KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
    KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
    
    # make the checker run with the right architecture
    CHECKFLAGS += --arch=$(ARCH)
    
    # insure the checker run with the right endianness
    CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
    
    # the checker needs the correct machine size
    CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
    
    # Default kernel image to build when no specific target is given.
    # KBUILD_IMAGE may be overruled on the command line or
    # 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
    
    #
    # 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)
    
    #
    # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
    # relocations required by build roots.  This is not defined in the
    # makefile but the argument can be passed to make if needed.
    #
    
    MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
    export MODLIB
    
    #
    # 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.
    
    ifdef INSTALL_MOD_STRIP
    ifeq ($(INSTALL_MOD_STRIP),1)
    mod_strip_cmd = $(STRIP) --strip-debug
    else
    mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
    endif # INSTALL_MOD_STRIP=1
    else
    mod_strip_cmd = true
    endif # INSTALL_MOD_STRIP
    export mod_strip_cmd
    
    # 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
        mod_compress_cmd = $(KGZIP) -n -f
      endif # CONFIG_MODULE_COMPRESS_GZIP
      ifdef CONFIG_MODULE_COMPRESS_XZ
        mod_compress_cmd = $(XZ) -f
      endif # CONFIG_MODULE_COMPRESS_XZ
    endif # CONFIG_MODULE_COMPRESS
    export mod_compress_cmd
    
    ifdef CONFIG_MODULE_SIG_ALL
    $(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
    else
    mod_sign_cmd = true
    endif
    export mod_sign_cmd
    
    HOST_LIBELF_LIBS = $(shell pkg-config libelf --libs 2>/dev/null || echo -lelf)
    
    ifdef CONFIG_STACK_VALIDATION
      has_libelf := $(call try-run,\
    		echo "int main() {}" | $(HOSTCC) -xc -o /dev/null $(HOST_LIBELF_LIBS) -,1,0)
      ifeq ($(has_libelf),1)
        objtool_target := tools/objtool FORCE
      else
        SKIP_STACK_VALIDATION := 1
        export SKIP_STACK_VALIDATION
      endif
    endif
    
    PHONY += prepare0
    
    export MODORDER := $(extmod-prefix)modules.order
    export MODULES_NSDEPS := $(extmod-prefix)modules.nsdeps
    
    ifeq ($(KBUILD_EXTMOD),)
    core-y		+= kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
    
    vmlinux-dirs	:= $(patsubst %/,%,$(filter %/, \
    		     $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
    		     $(libs-y) $(libs-m)))
    
    vmlinux-alldirs	:= $(sort $(vmlinux-dirs) Documentation \
    		     $(patsubst %/,%,$(filter %/, $(core-) \
    			$(drivers-) $(libs-))))
    
    subdir-modorder := $(addsuffix modules.order,$(filter %/, \
    			$(core-y) $(core-m) $(libs-y) $(libs-m) \
    			$(drivers-y) $(drivers-m)))
    
    build-dirs	:= $(vmlinux-dirs)
    clean-dirs	:= $(vmlinux-alldirs)
    
    # Externally visible symbols (used by link-vmlinux.sh)
    KBUILD_VMLINUX_OBJS := $(head-y) $(patsubst %/,%/built-in.a, $(core-y))
    KBUILD_VMLINUX_OBJS += $(addsuffix built-in.a, $(filter %/, $(libs-y)))
    ifdef CONFIG_MODULES
    KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
    KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
    else
    KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
    endif
    KBUILD_VMLINUX_OBJS += $(patsubst %/,%/built-in.a, $(drivers-y))
    
    export KBUILD_VMLINUX_OBJS KBUILD_VMLINUX_LIBS
    export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
    export LDFLAGS_vmlinux
    # used by scripts/Makefile.package
    export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) LICENSES arch include scripts tools)
    
    vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
    
    # Recurse until adjust_autoksyms.sh is satisfied
    PHONY += autoksyms_recursive
    ifdef CONFIG_TRIM_UNUSED_KSYMS
    # 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)
    KBUILD_MODULES := 1
    
    autoksyms_recursive: descend modules.order
    	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
    	  "$(MAKE) -f $(srctree)/Makefile vmlinux"
    endif
    
    autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
    
    quiet_cmd_autoksyms_h = GEN     $@
          cmd_autoksyms_h = mkdir -p $(dir $@); \
    			$(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@
    
    $(autoksyms_h):
    	$(call cmd,autoksyms_h)
    
    ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
    
    # Final link of vmlinux with optional arch pass after final link
    cmd_link-vmlinux =                                                 \
    	$(CONFIG_SHELL) $< $(LD) $(KBUILD_LDFLAGS) $(LDFLAGS_vmlinux) ;    \
    	$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
    
    vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
    	+$(call if_changed,link-vmlinux)
    
    targets := vmlinux
    
    # The actual objects are generated when descending,
    # make sure no implicit rule kicks in
    $(sort $(vmlinux-deps) $(subdir-modorder)): descend ;
    
    filechk_kernel.release = \
    	echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
    
    # Store (new) KERNELRELEASE string in include/config/kernel.release
    include/config/kernel.release: FORCE
    	$(call filechk,kernel.release)
    
    # Additional helpers built in scripts/
    # Carefully list dependencies so we do not try to build scripts twice
    # in parallel
    PHONY += scripts
    scripts: scripts_basic scripts_dtc
    	$(Q)$(MAKE) $(build)=$(@)
    
    # Things we need to do before we recursively start building the kernel
    # 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.
    
    PHONY += prepare archprepare
    
    archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
    	asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h \
    	include/generated/autoconf.h
    
    prepare0: archprepare
    	$(Q)$(MAKE) $(build)=scripts/mod
    	$(Q)$(MAKE) $(build)=.
    
    # All the preparing..
    prepare: prepare0 prepare-objtool
    
    # Support for using generic headers in asm-generic
    asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
    
    PHONY += asm-generic uapi-asm-generic
    asm-generic: uapi-asm-generic
    	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
    	generic=include/asm-generic
    uapi-asm-generic:
    	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
    	generic=include/uapi/asm-generic
    
    PHONY += prepare-objtool
    prepare-objtool: $(objtool_target)
    ifeq ($(SKIP_STACK_VALIDATION),1)
    ifdef CONFIG_UNWINDER_ORC
    	@echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
    	@false
    else
    	@echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
    endif
    endif
    
    # 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
    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
    
    define filechk_version.h
    	echo \#define LINUX_VERSION_CODE $(shell                         \
    	expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
    	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))'
    endef
    
    $(version_h): FORCE
    	$(call filechk,version.h)
    	$(Q)rm -f $(old_version_h)
    
    include/generated/utsrelease.h: include/config/kernel.release FORCE
    	$(call filechk,utsrelease.h)
    
    PHONY += headerdep
    headerdep:
    	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
    	$(srctree)/scripts/headerdep.pl -I$(srctree)/include
    
    # ---------------------------------------------------------------------------
    # Kernel headers
    
    #Default location for installed headers
    export INSTALL_HDR_PATH = $(objtree)/usr
    
    quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
          cmd_headers_install = \
    	mkdir -p $(INSTALL_HDR_PATH); \
    	rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
    	usr/include $(INSTALL_HDR_PATH)
    
    PHONY += headers_install
    headers_install: headers
    	$(call cmd,headers_install)
    
    PHONY += archheaders archscripts
    
    hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
    
    PHONY += headers
    headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
    	$(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
    	  $(error Headers not exportable for the $(SRCARCH) architecture))
    	$(Q)$(MAKE) $(hdr-inst)=include/uapi
    	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
    
    # Deprecated. It is no-op now.
    PHONY += headers_check
    headers_check:
    	@:
    
    ifdef CONFIG_HEADERS_INSTALL
    prepare: headers
    endif
    
    PHONY += scripts_unifdef
    scripts_unifdef: scripts_basic
    	$(Q)$(MAKE) $(build)=scripts scripts/unifdef
    
    # ---------------------------------------------------------------------------
    # Kernel selftest
    
    PHONY += kselftest
    kselftest:
    	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
    
    kselftest-%: FORCE
    	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
    
    PHONY += kselftest-merge
    kselftest-merge:
    	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
    	$(Q)find $(srctree)/tools/testing/selftests -name config | \
    		xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
    	$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
    
    # ---------------------------------------------------------------------------
    # Devicetree files
    
    ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
    dtstree := arch/$(SRCARCH)/boot/dts
    endif
    
    ifneq ($(dtstree),)
    
    %.dtb: include/config/kernel.release scripts_dtc
    	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
    
    PHONY += dtbs dtbs_install dtbs_check
    dtbs: include/config/kernel.release scripts_dtc
    	$(Q)$(MAKE) $(build)=$(dtstree)
    
    ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
    export CHECK_DTBS=y
    dtbs: dt_binding_check
    endif
    
    dtbs_check: dtbs
    
    dtbs_install:
    	$(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
    
    ifdef CONFIG_OF_EARLY_FLATTREE
    all: dtbs
    endif
    
    endif
    
    PHONY += scripts_dtc
    scripts_dtc: scripts_basic
    	$(Q)$(MAKE) $(build)=scripts/dtc
    
    ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
    export CHECK_DT_BINDING=y
    endif
    
    PHONY += dt_binding_check
    dt_binding_check: scripts_dtc
    	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
    
    # ---------------------------------------------------------------------------
    # Modules
    
    ifdef CONFIG_MODULES
    
    # By default, build modules as well
    
    all: modules
    
    # 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.
    ifdef CONFIG_MODVERSIONS
      KBUILD_BUILTIN := 1
    endif
    
    # Build modules
    #
    # A module can be listed more than once in obj-m resulting in
    # duplicate lines in modules.order files.  Those are removed
    # using awk while concatenating to the final file.
    
    PHONY += modules
    modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_check
    	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
    
    PHONY += modules_check
    modules_check: modules.order
    	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
    
    cmd_modules_order = $(AWK) '!x[$$0]++' $(real-prereqs) > $@
    
    modules.order: $(subdir-modorder) FORCE
    	$(call if_changed,modules_order)
    
    targets += modules.order
    
    # Target to prepare building external modules
    PHONY += modules_prepare
    modules_prepare: prepare
    
    # Target to install modules
    PHONY += modules_install
    modules_install: _modinst_ _modinst_post
    
    PHONY += _modinst_
    _modinst_:
    	@rm -rf $(MODLIB)/kernel
    	@rm -f $(MODLIB)/source
    	@mkdir -p $(MODLIB)/kernel
    	@ln -s $(abspath $(srctree)) $(MODLIB)/source
    	@if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
    		rm -f $(MODLIB)/build ; \
    		ln -s $(CURDIR) $(MODLIB)/build ; \
    	fi
    	@sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order
    	@cp -f modules.builtin $(MODLIB)/
    	@cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
    	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
    
    # This depmod is only for convenience to give the initial
    # boot a modules.dep even before / is mounted read-write.  However the
    # boot script depmod is the master version.
    PHONY += _modinst_post
    _modinst_post: _modinst_
    	$(call cmd,depmod)
    
    ifeq ($(CONFIG_MODULE_SIG), y)
    PHONY += modules_sign
    modules_sign:
    	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
    endif
    
    else # CONFIG_MODULES
    
    # Modules not configured
    # ---------------------------------------------------------------------------
    
    PHONY += modules modules_install
    modules modules_install:
    	@echo >&2
    	@echo >&2 "The present kernel configuration has modules disabled."
    	@echo >&2 "Type 'make config' and enable loadable module support."
    	@echo >&2 "Then build a kernel with module support enabled."
    	@echo >&2
    	@exit 1
    
    endif # CONFIG_MODULES
    
    ###
    # Cleaning is done on three levels.
    # make clean     Delete most generated files
    #                Leave enough to build external modules
    # make mrproper  Delete the current configuration, and all generated files
    # make distclean Remove editor backup files, patch leftover files and the like
    
    # Directories & files removed with 'make clean'
    CLEAN_FILES += include/ksym vmlinux.symvers \
    	       modules.builtin modules.builtin.modinfo modules.nsdeps
    
    # Directories & files removed with 'make mrproper'
    MRPROPER_FILES += include/config include/generated          \
    		  arch/$(SRCARCH)/include/generated .tmp_objdiff \
    		  debian snap tar-install \
    		  .config .config.old .version \
    		  Module.symvers \
    		  signing_key.pem signing_key.priv signing_key.x509	\
    		  x509.genkey extra_certificates signing_key.x509.keyid	\
    		  signing_key.x509.signer vmlinux-gdb.py \
    		  *.spec
    
    # Directories & files removed with 'make distclean'
    DISTCLEAN_FILES += tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS
    
    # clean - Delete most, but leave enough to build external modules
    #
    clean: rm-files := $(CLEAN_FILES)
    
    PHONY += archclean vmlinuxclean
    
    vmlinuxclean:
    	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
    	$(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
    
    clean: archclean vmlinuxclean
    
    # mrproper - Delete all generated files, including .config
    #
    mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
    mrproper-dirs      := $(addprefix _mrproper_,scripts)
    
    PHONY += $(mrproper-dirs) mrproper
    $(mrproper-dirs):
    	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
    
    mrproper: clean $(mrproper-dirs)
    	$(call cmd,rmfiles)
    
    # distclean
    #
    distclean: rm-files := $(wildcard $(DISTCLEAN_FILES))
    
    PHONY += distclean
    
    distclean: mrproper
    	$(call cmd,rmfiles)
    	@find $(srctree) $(RCS_FIND_IGNORE) \
    		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
    		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
    		-o -name 'core' \) \
    		-type f -print | xargs rm -f
    
    
    # Packaging of the kernel to various formats
    # ---------------------------------------------------------------------------
    
    %src-pkg: FORCE
    	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
    %pkg: include/config/kernel.release FORCE
    	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
    
    # Brief documentation of the typical targets used
    # ---------------------------------------------------------------------------
    
    boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
    boards := $(sort $(notdir $(boards)))
    board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
    board-dirs := $(sort $(notdir $(board-dirs:/=)))
    
    PHONY += help
    help:
    	@echo  'Cleaning targets:'
    	@echo  '  clean		  - Remove most generated files but keep the config and'
    	@echo  '                    enough build support to build external modules'
    	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
    	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
    	@echo  ''
    	@echo  'Configuration targets:'
    	@$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
    	@echo  ''
    	@echo  'Other generic targets:'
    	@echo  '  all		  - Build all targets marked with [*]'
    	@echo  '* vmlinux	  - Build the bare kernel'
    	@echo  '* modules	  - Build all modules'
    	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
    	@echo  '  dir/            - Build all files in dir and below'
    	@echo  '  dir/file.[ois]  - Build specified target only'
    	@echo  '  dir/file.ll     - Build the LLVM assembly file'
    	@echo  '                    (requires compiler support for LLVM assembly generation)'
    	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
    	@echo  '                    (requires a recent binutils and recent build (System.map))'
    	@echo  '  dir/file.ko     - Build module including final link'
    	@echo  '  modules_prepare - Set up for building external modules'
    	@echo  '  tags/TAGS	  - Generate tags file for editors'
    	@echo  '  cscope	  - Generate cscope index'
    	@echo  '  gtags           - Generate GNU GLOBAL index'
    	@echo  '  kernelrelease	  - Output the release version string (use with make -s)'
    	@echo  '  kernelversion	  - Output the version stored in Makefile (use with make -s)'
    	@echo  '  image_name	  - Output the image name (use with make -s)'
    	@echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
    	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
    	 echo  ''
    	@echo  'Static analysers:'
    	@echo  '  checkstack      - Generate a list of stack hogs'
    	@echo  '  namespacecheck  - Name space analysis on compiled kernel'
    	@echo  '  versioncheck    - Sanity check on version.h usage'
    	@echo  '  includecheck    - Check for duplicate included header files'
    	@echo  '  export_report   - List the usages of all exported symbols'
    	@echo  '  headerdep       - Detect inclusion cycles in headers'
    	@echo  '  coccicheck      - Check with Coccinelle'
    	@echo  ''
    	@echo  'Tools:'
    	@echo  '  nsdeps          - Generate missing symbol namespace dependencies'
    	@echo  ''
    	@echo  'Kernel selftest:'
    	@echo  '  kselftest         - Build and run kernel selftest'
    	@echo  '                      Build, install, and boot kernel before'
    	@echo  '                      running kselftest on it'
    	@echo  '                      Run as root for full coverage'
    	@echo  '  kselftest-all     - Build kernel selftest'
    	@echo  '  kselftest-install - Build and install kernel selftest'
    	@echo  '  kselftest-clean   - Remove all generated kselftest files'
    	@echo  '  kselftest-merge   - Merge all the config dependencies of'
    	@echo  '		      kselftest to existing .config.'
    	@echo  ''
    	@$(if $(dtstree), \
    		echo 'Devicetree:'; \
    		echo '* dtbs             - Build device tree blobs for enabled boards'; \
    		echo '  dtbs_install     - Install dtbs to $(INSTALL_DTBS_PATH)'; \
    		echo '  dt_binding_check - Validate device tree binding documents'; \
    		echo '  dtbs_check       - Validate device tree source files';\
    		echo '')
    
    	@echo 'Userspace tools targets:'
    	@echo '  use "make tools/help"'
    	@echo '  or  "cd tools; make help"'
    	@echo  ''
    	@echo  'Kernel packaging:'
    	@$(MAKE) -f $(srctree)/scripts/Makefile.package help
    	@echo  ''
    	@echo  'Documentation targets:'
    	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
    	@echo  ''
    	@echo  'Architecture specific targets ($(SRCARCH)):'
    	@$(if $(archhelp),$(archhelp),\
    		echo '  No architecture specific help defined for $(SRCARCH)')
    	@echo  ''
    	@$(if $(boards), \
    		$(foreach b, $(boards), \
    		printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
    		echo '')
    	@$(if $(board-dirs), \
    		$(foreach b, $(board-dirs), \
    		printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
    		printf "  %-16s - Show all of the above\\n" help-boards; \
    		echo '')
    
    	@echo  '  make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
    	@echo  '  make V=2   [targets] 2 => give reason for rebuild of target'
    	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
    	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
    	@echo  '                       (sparse by default)'
    	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
    	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
    	@echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
    	@echo  '		1: warnings which may be relevant and do not occur too often'
    	@echo  '		2: warnings which occur quite often but may still be relevant'
    	@echo  '		3: more obscure warnings, can most likely be ignored'
    	@echo  '		Multiple levels can be combined with W=12 or W=123'
    	@echo  ''
    	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
    	@echo  'For further info see the ./README file'
    
    
    help-board-dirs := $(addprefix help-,$(board-dirs))
    
    help-boards: $(help-board-dirs)
    
    boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
    
    $(help-board-dirs): help-%:
    	@echo  'Architecture specific targets ($(SRCARCH) $*):'
    	@$(if $(boards-per-dir), \
    		$(foreach b, $(boards-per-dir), \
    		printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
    		echo '')
    
    
    # Documentation targets
    # ---------------------------------------------------------------------------
    DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
    	       linkcheckdocs dochelp refcheckdocs
    PHONY += $(DOC_TARGETS)
    $(DOC_TARGETS):
    	$(Q)$(MAKE) $(build)=Documentation $@
    
    # Misc
    # ---------------------------------------------------------------------------
    
    PHONY += scripts_gdb
    scripts_gdb: prepare0
    	$(Q)$(MAKE) $(build)=scripts/gdb
    	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
    
    ifdef CONFIG_GDB_SCRIPTS
    all: scripts_gdb
    endif
    
    else # KBUILD_EXTMOD
    
    ###
    # External module support.
    # When building external modules the kernel used as basis is considered
    # read-only, and no consistency checks are made and the make
    # system is not used on the basis kernel. If updates are required
    # in the basis kernel ordinary make commands (without M=...) must
    # be used.
    #
    # The following are the only valid targets when building external
    # modules.
    # make M=dir clean     Delete all automatically generated files
    # make M=dir modules   Make all modules in specified dir
    # make M=dir	       Same as 'make M=dir modules'
    # make M=dir modules_install
    #                      Install the modules built in the module directory
    #                      Assumes install directory is already created
    
    # We are always building modules
    KBUILD_MODULES := 1
    
    build-dirs := $(KBUILD_EXTMOD)
    PHONY += modules
    modules: descend
    	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
    
    PHONY += modules_install
    modules_install: _emodinst_ _emodinst_post
    
    install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
    PHONY += _emodinst_
    _emodinst_:
    	$(Q)mkdir -p $(MODLIB)/$(install-dir)
    	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
    
    PHONY += _emodinst_post
    _emodinst_post: _emodinst_
    	$(call cmd,depmod)
    
    clean-dirs := $(KBUILD_EXTMOD)
    clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps
    
    PHONY += help
    help:
    	@echo  '  Building external modules.'
    	@echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
    	@echo  ''
    	@echo  '  modules         - default target, build the module(s)'
    	@echo  '  modules_install - install the module'
    	@echo  '  clean           - remove generated files in module directory only'
    	@echo  ''
    
    PHONY += prepare
    endif # KBUILD_EXTMOD
    
    # Single targets
    # ---------------------------------------------------------------------------
    # To build individual files in subdirectories, you can do like this:
    #
    #   make foo/bar/baz.s
    #
    # The supported suffixes for single-target are listed in 'single-targets'
    #
    # To build only under specific subdirectories, you can do like this:
    #
    #   make foo/bar/baz/
    
    ifdef single-build
    
    # .ko is special because modpost is needed
    single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
    single-no-ko := $(sort $(patsubst %.ko,%.mod, $(MAKECMDGOALS)))
    
    $(single-ko): single_modpost
    	@:
    $(single-no-ko): descend
    	@:
    
    ifeq ($(KBUILD_EXTMOD),)
    # For the single build of in-tree modules, use a temporary file to avoid
    # the situation of modules_install installing an invalid modules.order.
    MODORDER := .modules.tmp
    endif
    
    PHONY += single_modpost
    single_modpost: $(single-no-ko)
    	$(Q){ $(foreach m, $(single-ko), echo $(extmod-prefix)$m;) } > $(MODORDER)
    	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
    
    KBUILD_MODULES := 1
    
    export KBUILD_SINGLE_TARGETS := $(addprefix $(extmod-prefix), $(single-no-ko))
    
    # trim unrelated directories
    build-dirs := $(foreach d, $(build-dirs), \
    			$(if $(filter $(d)/%, $(KBUILD_SINGLE_TARGETS)), $(d)))
    
    endif
    
    ifndef CONFIG_MODULES
    KBUILD_MODULES :=
    endif
    
    # Handle descending into subdirectories listed in $(build-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
    PHONY += descend $(build-dirs)
    descend: $(build-dirs)
    $(build-dirs): prepare
    	$(Q)$(MAKE) $(build)=$@ \
    	single-build=$(if $(filter-out $@/, $(filter $@/%, $(single-no-ko))),1) \
    	need-builtin=1 need-modorder=1
    
    clean-dirs := $(addprefix _clean_, $(clean-dirs))
    PHONY += $(clean-dirs) clean
    $(clean-dirs):
    	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
    
    clean: $(clean-dirs)
    	$(call cmd,rmfiles)
    	@find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
    		\( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
    		-o -name '*.ko.*' \
    		-o -name '*.dtb' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
    		-o -name '*.dwo' -o -name '*.lst' \
    		-o -name '*.su' -o -name '*.mod' \
    		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
    		-o -name '*.lex.c' -o -name '*.tab.[ch]' \
    		-o -name '*.asn1.[ch]' \
    		-o -name '*.symtypes' -o -name 'modules.order' \
    		-o -name '.tmp_*.o.*' \
    		-o -name '*.c.[012]*.*' \
    		-o -name '*.ll' \
    		-o -name '*.gcno' \) -type f -print | xargs rm -f
    
    # Generate tags for editors
    # ---------------------------------------------------------------------------
    quiet_cmd_tags = GEN     $@
          cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
    
    tags TAGS cscope gtags: FORCE
    	$(call cmd,tags)
    
    # Script to generate missing namespace dependencies
    # ---------------------------------------------------------------------------
    
    PHONY += nsdeps
    nsdeps: export KBUILD_NSDEPS=1
    nsdeps: modules
    	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
    
    # Scripts to check various things for consistency
    # ---------------------------------------------------------------------------
    
    PHONY += includecheck versioncheck coccicheck namespacecheck export_report
    
    includecheck:
    	find $(srctree)/* $(RCS_FIND_IGNORE) \
    		-name '*.[hcS]' -type f -print | sort \
    		| xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
    
    versioncheck:
    	find $(srctree)/* $(RCS_FIND_IGNORE) \
    		-name '*.[hcS]' -type f -print | sort \
    		| xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
    
    coccicheck:
    	$(Q)$(BASH) $(srctree)/scripts/$@
    
    namespacecheck:
    	$(PERL) $(srctree)/scripts/namespace.pl
    
    export_report:
    	$(PERL) $(srctree)/scripts/export_report.pl
    
    PHONY += checkstack kernelrelease kernelversion image_name
    
    # UML needs a little special treatment here.  It wants to use the host
    # toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
    # else wants $(ARCH), including people doing cross-builds, which means
    # that $(SUBARCH) doesn't work here.
    ifeq ($(ARCH), um)
    CHECKSTACK_ARCH := $(SUBARCH)
    else
    CHECKSTACK_ARCH := $(ARCH)
    endif
    checkstack:
    	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
    	$(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
    
    kernelrelease:
    	@echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
    
    kernelversion:
    	@echo $(KERNELVERSION)
    
    image_name:
    	@echo $(KBUILD_IMAGE)
    
    # Clear a bunch of variables before executing the submake
    
    ifeq ($(quiet),silent_)
    tools_silent=s
    endif
    
    tools/: FORCE
    	$(Q)mkdir -p $(objtree)/tools
    	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
    
    tools/%: FORCE
    	$(Q)mkdir -p $(objtree)/tools
    	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
    
    quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
          cmd_rmfiles = rm -rf $(rm-files)
    
    # Run depmod only if we have System.map and depmod is executable
    quiet_cmd_depmod = DEPMOD  $(KERNELRELEASE)
          cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
                       $(KERNELRELEASE)
    
    # read saved command lines for existing targets
    existing-targets := $(wildcard $(sort $(targets)))
    
    -include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
    
    endif # config-build
    endif # mixed-build
    endif # need-sub-make
    
    PHONY += FORCE
    FORCE:
    
    # Declare the contents of the PHONY variable as phony.  We keep that
    # information in a variable so we can use it in if_changed and friends.
    .PHONY: $(PHONY)