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|
# SPDX-License-Identifier: GPL-2.0
VERSION = 6
PATCHLEVEL = 7
SUBLEVEL = 0
EXTRAVERSION = -rc8
NAME = Hurr durr I'ma ninja sloth
# *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.
ifeq ($(filter undefine,$(.FEATURES)),)
$(error GNU Make >= 3.82 is required. Your Make version is $(MAKE_VERSION))
endif
$(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.
this-makefile := $(lastword $(MAKEFILE_LIST))
export abs_srctree := $(realpath $(dir $(this-makefile)))
export abs_objtree := $(CURDIR)
ifneq ($(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
# ---------------------------------------------------------------------------
#
# Most of build commands in Kbuild start with "cmd_". You can optionally define
# "quiet_cmd_*". If defined, the short log is printed. Otherwise, no log from
# that command is printed by default.
#
# e.g.)
# quiet_cmd_depmod = DEPMOD $(MODLIB)
# cmd_depmod = $(srctree)/scripts/depmod.sh $(DEPMOD) $(KERNELRELEASE)
#
# A simple variant is to prefix commands with $(Q) - that's useful
# for commands that shall be hidden in non-verbose mode.
#
# $(Q)$(MAKE) $(build)=scripts/basic
#
# If KBUILD_VERBOSE contains 1, the whole command is echoed.
# If KBUILD_VERBOSE contains 2, the reason for rebuilding is printed.
#
# To put more focus on warnings, be less verbose as default
# Use 'make V=1' to see the full commands
ifeq ("$(origin V)", "command line")
KBUILD_VERBOSE = $(V)
endif
quiet = quiet_
Q = @
ifneq ($(findstring 1, $(KBUILD_VERBOSE)),)
quiet =
Q =
endif
# If the user is running make -s (silent mode), suppress echoing of
# commands
# make-4.0 (and later) keep single letter options in the 1st word of MAKEFLAGS.
ifeq ($(filter 3.%,$(MAKE_VERSION)),)
short-opts := $(firstword -$(MAKEFLAGS))
else
short-opts := $(filter-out --%,$(MAKEFLAGS))
endif
ifneq ($(findstring s,$(short-opts)),)
quiet=silent_
override KBUILD_VERBOSE :=
endif
export quiet Q KBUILD_VERBOSE
# 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 = $(C)
endif
ifndef KBUILD_CHECKSRC
KBUILD_CHECKSRC = 0
endif
export KBUILD_CHECKSRC
# Enable "clippy" (a linter) as part of the Rust compilation.
#
# Use 'make CLIPPY=1' to enable it.
ifeq ("$(origin CLIPPY)", "command line")
KBUILD_CLIPPY := $(CLIPPY)
endif
export KBUILD_CLIPPY
# Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
# directory of external module to build. Setting M= takes precedence.
ifeq ("$(origin M)", "command line")
KBUILD_EXTMOD := $(M)
endif
$(if $(word 2, $(KBUILD_EXTMOD)), \
$(error building multiple external modules is not supported))
$(foreach x, % :, $(if $(findstring $x, $(KBUILD_EXTMOD)), \
$(error module directory path cannot contain '$x')))
# Remove trailing slashes
ifneq ($(filter %/, $(KBUILD_EXTMOD)),)
KBUILD_EXTMOD := $(shell dirname $(KBUILD_EXTMOD).)
endif
export KBUILD_EXTMOD
# Kbuild will save output files in the current working directory.
# This does not need to match to the root of the kernel source tree.
#
# For example, you can do this:
#
# cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
#
# If you want to save output files in a different location, there are
# two syntaxes to specify it.
#
# 1) O=
# Use "make O=dir/to/store/output/files/"
#
# 2) Set KBUILD_OUTPUT
# Set the environment variable KBUILD_OUTPUT to point to the output directory.
# export KBUILD_OUTPUT=dir/to/store/output/files/; make
#
# The O= assignment takes precedence over the KBUILD_OUTPUT environment
# variable.
# Do we want to change the working directory?
ifeq ("$(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 $(abs_objtree))
endif # ifneq ($(KBUILD_OUTPUT),)
ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
$(error source directory cannot contain spaces or colons)
endif
ifneq ($(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.
$(this-makefile): ;
endif
export sub_make_done := 1
endif # sub_make_done
ifeq ($(abs_objtree),$(CURDIR))
# Suppress "Entering directory ..." if we are at the final work directory.
no-print-directory := --no-print-directory
else
# Recursion to show "Entering directory ..."
need-sub-make := 1
endif
ifeq ($(filter --no-print-directory, $(MAKEFLAGS)),)
# If --no-print-directory is unset, recurse once again to set it.
# You may end up recursing into __sub-make twice. This is needed due to the
# behavior change in GNU Make 4.4.1.
need-sub-make := 1
endif
ifeq ($(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) $(no-print-directory) -C $(abs_objtree) \
-f $(abs_srctree)/Makefile $(MAKECMDGOALS)
else # need-sub-make
# We process the rest of the Makefile if this is the final invocation of make
ifeq ($(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
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 rustavailable rustfmt rustfmtcheck
no-sync-config-targets := $(no-dot-config-targets) %install modules_sign kernelrelease \
image_name
single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.rsi %.s %.symtypes %/
config-build :=
mixed-build :=
need-config := 1
may-sync-config := 1
single-build :=
ifneq ($(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
need-compiler := $(may-sync-config)
ifneq ($(KBUILD_EXTMOD),)
may-sync-config :=
endif
ifeq ($(KBUILD_EXTMOD),)
ifneq ($(filter %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 $(srctree)/scripts/Kbuild.include
# Read KERNELRELEASE from include/config/kernel.release (if it exists)
KERNELRELEASE = $(call read-file, include/config/kernel.release)
KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
include $(srctree)/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=arm64
# 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=aarch64-linux-gnu-
# 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 ($(ARCH),sparc64)
SRCARCH := sparc
endif
# Additional ARCH settings for parisc
ifeq ($(ARCH),parisc64)
SRCARCH := parisc
endif
export cross_compiling :=
ifneq ($(SRCARCH),$(SUBARCH))
cross_compiling := 1
endif
KCONFIG_CONFIG ?= .config
export KCONFIG_CONFIG
# 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),)
ifneq ($(filter %/,$(LLVM)),)
LLVM_PREFIX := $(LLVM)
else ifneq ($(filter -%,$(LLVM)),)
LLVM_SUFFIX := $(LLVM)
endif
HOSTCC = $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
HOSTCXX = $(LLVM_PREFIX)clang++$(LLVM_SUFFIX)
else
HOSTCC = gcc
HOSTCXX = g++
endif
HOSTRUSTC = rustc
HOSTPKG_CONFIG = pkg-config
KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
-O2 -fomit-frame-pointer -std=gnu11
KBUILD_USERCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(USERCFLAGS)
KBUILD_USERLDFLAGS := $(USERLDFLAGS)
# These flags apply to all Rust code in the tree, including the kernel and
# host programs.
export rust_common_flags := --edition=2021 \
-Zbinary_dep_depinfo=y \
-Dunsafe_op_in_unsafe_fn -Drust_2018_idioms \
-Dunreachable_pub -Dnon_ascii_idents \
-Wmissing_docs \
-Drustdoc::missing_crate_level_docs \
-Dclippy::correctness -Dclippy::style \
-Dclippy::suspicious -Dclippy::complexity \
-Dclippy::perf \
-Dclippy::let_unit_value -Dclippy::mut_mut \
-Dclippy::needless_bitwise_bool \
-Dclippy::needless_continue \
-Dclippy::no_mangle_with_rust_abi \
-Wclippy::dbg_macro
KBUILD_HOSTCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
KBUILD_HOSTRUSTFLAGS := $(rust_common_flags) -O -Cstrip=debuginfo \
-Zallow-features= $(HOSTRUSTFLAGS)
KBUILD_HOSTLDFLAGS := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
KBUILD_HOSTLDLIBS := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
# Make variables (CC, etc...)
CPP = $(CC) -E
ifneq ($(LLVM),)
CC = $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
LD = $(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX)
AR = $(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX)
NM = $(LLVM_PREFIX)llvm-nm$(LLVM_SUFFIX)
OBJCOPY = $(LLVM_PREFIX)llvm-objcopy$(LLVM_SUFFIX)
OBJDUMP = $(LLVM_PREFIX)llvm-objdump$(LLVM_SUFFIX)
READELF = $(LLVM_PREFIX)llvm-readelf$(LLVM_SUFFIX)
STRIP = $(LLVM_PREFIX)llvm-strip$(LLVM_SUFFIX)
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
STRIP = $(CROSS_COMPILE)strip
endif
RUSTC = rustc
RUSTDOC = rustdoc
RUSTFMT = rustfmt
CLIPPY_DRIVER = clippy-driver
BINDGEN = bindgen
CARGO = cargo
PAHOLE = pahole
RESOLVE_BTFIDS = $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
LEX = flex
YACC = bison
AWK = awk
INSTALLKERNEL := installkernel
PERL = perl
PYTHON3 = python3
CHECK = sparse
BASH = bash
KGZIP = gzip
KBZIP2 = bzip2
KLZOP = lzop
LZMA = lzma
LZ4 = lz4c
XZ = xz
ZSTD = zstd
CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
-Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
NOSTDINC_FLAGS :=
CFLAGS_MODULE =
RUSTFLAGS_MODULE =
AFLAGS_MODULE =
LDFLAGS_MODULE =
CFLAGS_KERNEL =
RUSTFLAGS_KERNEL =
AFLAGS_KERNEL =
LDFLAGS_vmlinux =
# Use USERINCLUDE when you must reference the UAPI directories only.
USERINCLUDE := \
-I$(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/compiler-version.h \
-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 :=
KBUILD_CFLAGS += -std=gnu11
KBUILD_CFLAGS += -fshort-wchar
KBUILD_CFLAGS += -funsigned-char
KBUILD_CFLAGS += -fno-common
KBUILD_CFLAGS += -fno-PIE
KBUILD_CFLAGS += -fno-strict-aliasing
KBUILD_CPPFLAGS := -D__KERNEL__
KBUILD_RUSTFLAGS := $(rust_common_flags) \
--target=$(objtree)/scripts/target.json \
-Cpanic=abort -Cembed-bitcode=n -Clto=n \
-Cforce-unwind-tables=n -Ccodegen-units=1 \
-Csymbol-mangling-version=v0 \
-Crelocation-model=static \
-Zfunction-sections=n \
-Dclippy::float_arithmetic
KBUILD_AFLAGS_KERNEL :=
KBUILD_CFLAGS_KERNEL :=
KBUILD_RUSTFLAGS_KERNEL :=
KBUILD_AFLAGS_MODULE := -DMODULE
KBUILD_CFLAGS_MODULE := -DMODULE
KBUILD_RUSTFLAGS_MODULE := --cfg MODULE
KBUILD_LDFLAGS_MODULE :=
KBUILD_LDFLAGS :=
CLANG_FLAGS :=
ifeq ($(KBUILD_CLIPPY),1)
RUSTC_OR_CLIPPY_QUIET := CLIPPY
RUSTC_OR_CLIPPY = $(CLIPPY_DRIVER)
else
RUSTC_OR_CLIPPY_QUIET := RUSTC
RUSTC_OR_CLIPPY = $(RUSTC)
endif
ifdef RUST_LIB_SRC
export RUST_LIB_SRC
endif
# Allows the usage of unstable features in stable compilers.
export RUSTC_BOOTSTRAP := 1
export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG
export RUSTC RUSTDOC RUSTFMT RUSTC_OR_CLIPPY_QUIET RUSTC_OR_CLIPPY BINDGEN CARGO
export HOSTRUSTC KBUILD_HOSTRUSTFLAGS
export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS
export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
export KBUILD_RUSTFLAGS RUSTFLAGS_KERNEL RUSTFLAGS_MODULE
export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_RUSTFLAGS_MODULE KBUILD_LDFLAGS_MODULE
export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL KBUILD_RUSTFLAGS_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
PHONY += outputmakefile
ifdef building_out_of_srctree
# 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
quiet_cmd_makefile = GEN Makefile
cmd_makefile = { \
echo "\# Automatically generated by $(srctree)/Makefile: don't edit"; \
echo "include $(srctree)/Makefile"; \
} > Makefile
outputmakefile:
@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
$(call cmd,makefile)
$(Q)test -e .gitignore || \
{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
endif
# The expansion should be delayed until arch/$(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 = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1))
ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
include $(srctree)/scripts/Makefile.clang
endif
# Include this also for config targets because some architectures need
# cc-cross-prefix to determine CROSS_COMPILE.
ifdef need-compiler
include $(srctree)/scripts/Makefile.compiler
endif
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 $(srctree)/arch/$(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
targets :=
# 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 %compile_commands.json clang-%,$(MAKECMDGOALS)),)
KBUILD_MODULES := 1
endif
ifeq ($(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 :=
drivers-y :=
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
ifdef CONFIG_CC_IS_GCC
CFLAGS_GCOV += -fno-tree-loop-im
endif
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
include $(srctree)/arch/$(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)
#
# Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
# so you cannot notice that Kconfig is waiting for the user input.
%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h %/generated/rustc_cfg: $(KCONFIG_CONFIG)
$(Q)$(kecho) " SYNC $@"
$(Q)$(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:
@test -e include/generated/autoconf.h -a -e $@ || ( \
echo >&2; \
echo >&2 " ERROR: Kernel configuration is invalid."; \
echo >&2 " include/generated/autoconf.h or $@ are missing.";\
echo >&2 " Run 'make oldconfig && make prepare' on kernel src to fix it."; \
echo >&2 ; \
/bin/false)
endif # may-sync-config
endif # need-config
KBUILD_CFLAGS += -fno-delete-null-pointer-checks
ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
KBUILD_CFLAGS += -O2
KBUILD_RUSTFLAGS += -Copt-level=2
else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
KBUILD_CFLAGS += -Os
KBUILD_RUSTFLAGS += -Copt-level=s
endif
# Always set `debug-assertions` and `overflow-checks` because their default
# depends on `opt-level` and `debug-assertions`, respectively.
KBUILD_RUSTFLAGS += -Cdebug-assertions=$(if $(CONFIG_RUST_DEBUG_ASSERTIONS),y,n)
KBUILD_RUSTFLAGS += -Coverflow-checks=$(if $(CONFIG_RUST_OVERFLOW_CHECKS),y,n)
# Tell gcc to never replace conditional load with a non-conditional one
ifdef CONFIG_CC_IS_GCC
# gcc-10 renamed --param=allow-store-data-races=0 to
# -fno-allow-store-data-races.
KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
KBUILD_CFLAGS += $(call cc-option,-fno-allow-store-data-races)
endif
ifdef CONFIG_READABLE_ASM
# Disable optimizations that make assembler listings hard to read.
# reorder blocks reorders the control in the function
# ipa clone creates specialized cloned functions
# partial inlining inlines only parts of functions
KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
endif
stackp-flags-y := -fno-stack-protector
stackp-flags-$(CONFIG_STACKPROTECTOR) := -fstack-protector
stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG) := -fstack-protector-strong
KBUILD_CFLAGS += $(stackp-flags-y)
KBUILD_RUSTFLAGS-$(CONFIG_WERROR) += -Dwarnings
KBUILD_RUSTFLAGS += $(KBUILD_RUSTFLAGS-y)
ifdef CONFIG_FRAME_POINTER
KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
KBUILD_RUSTFLAGS += -Cforce-frame-pointers=y
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.
# In the Rust target specification, "frame-pointer" is set explicitly
# to "may-omit".
ifndef CONFIG_FUNCTION_TRACER
KBUILD_CFLAGS += -fomit-frame-pointer
endif
endif
# Initialize all stack variables with a 0xAA pattern.
ifdef CONFIG_INIT_STACK_ALL_PATTERN
KBUILD_CFLAGS += -ftrivial-auto-var-init=pattern
endif
# Initialize all stack variables with a zero value.
ifdef CONFIG_INIT_STACK_ALL_ZERO
KBUILD_CFLAGS += -ftrivial-auto-var-init=zero
ifdef CONFIG_CC_HAS_AUTO_VAR_INIT_ZERO_ENABLER
# https://github.com/llvm/llvm-project/issues/44842
CC_AUTO_VAR_INIT_ZERO_ENABLER := -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
export CC_AUTO_VAR_INIT_ZERO_ENABLER
KBUILD_CFLAGS += $(CC_AUTO_VAR_INIT_ZERO_ENABLER)
endif
endif
# While VLAs have been removed, GCC produces unreachable stack probes
# for the randomize_kstack_offset feature. Disable it for all compilers.
KBUILD_CFLAGS += $(call cc-option, -fno-stack-clash-protection)
# Clear used registers at func exit (to reduce data lifetime and ROP gadgets).
ifdef CONFIG_ZERO_CALL_USED_REGS
KBUILD_CFLAGS += -fzero-call-used-regs=used-gpr
endif
ifdef CONFIG_FUNCTION_TRACER
ifdef CONFIG_FTRACE_MCOUNT_USE_CC
CC_FLAGS_FTRACE += -mrecord-mcount
ifdef CONFIG_HAVE_NOP_MCOUNT
ifeq ($(call cc-option-yn, -mnop-mcount),y)
CC_FLAGS_FTRACE += -mnop-mcount
CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
endif
endif
endif
ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
ifdef CONFIG_HAVE_OBJTOOL_NOP_MCOUNT
CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT
endif
endif
ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
ifdef CONFIG_HAVE_C_RECORDMCOUNT
BUILD_C_RECORDMCOUNT := y
export BUILD_C_RECORDMCOUNT
endif
endif
ifdef CONFIG_HAVE_FENTRY
# s390-linux-gnu-gcc did not support -mfentry until gcc-9.
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)
endif
# We trigger additional mismatches with less inlining
ifdef CONFIG_DEBUG_SECTION_MISMATCH
KBUILD_CFLAGS += -fno-inline-functions-called-once
endif
# `rustc`'s `-Zfunction-sections` applies to data too (as of 1.59.0).
ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
KBUILD_RUSTFLAGS_KERNEL += -Zfunction-sections=y
LDFLAGS_vmlinux += --gc-sections
endif
ifdef CONFIG_SHADOW_CALL_STACK
ifndef CONFIG_DYNAMIC_SCS
CC_FLAGS_SCS := -fsanitize=shadow-call-stack
KBUILD_CFLAGS += $(CC_FLAGS_SCS)
endif
export CC_FLAGS_SCS
endif
ifdef CONFIG_LTO_CLANG
ifdef CONFIG_LTO_CLANG_THIN
CC_FLAGS_LTO := -flto=thin -fsplit-lto-unit
KBUILD_LDFLAGS += --thinlto-cache-dir=$(extmod_prefix).thinlto-cache
else
CC_FLAGS_LTO := -flto
endif
CC_FLAGS_LTO += -fvisibility=hidden
# Limit inlining across translation units to reduce binary size
KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
# Check for frame size exceeding threshold during prolog/epilog insertion
# when using lld < 13.0.0.
ifneq ($(CONFIG_FRAME_WARN),0)
ifeq ($(call test-lt, $(CONFIG_LLD_VERSION), 130000),y)
KBUILD_LDFLAGS += -plugin-opt=-warn-stack-size=$(CONFIG_FRAME_WARN)
endif
endif
endif
ifdef CONFIG_LTO
KBUILD_CFLAGS += -fno-lto $(CC_FLAGS_LTO)
KBUILD_AFLAGS += -fno-lto
export CC_FLAGS_LTO
endif
ifdef CONFIG_CFI_CLANG
CC_FLAGS_CFI := -fsanitize=kcfi
KBUILD_CFLAGS += $(CC_FLAGS_CFI)
export CC_FLAGS_CFI
endif
ifneq ($(CONFIG_FUNCTION_ALIGNMENT),0)
KBUILD_CFLAGS += -falign-functions=$(CONFIG_FUNCTION_ALIGNMENT)
endif
# arch Makefile may override CC so keep this after arch Makefile is included
NOSTDINC_FLAGS += -nostdinc
# To gain proper coverage for CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE,
# the kernel uses only C99 flexible arrays for dynamically sized trailing
# arrays. Enforce this for everything that may examine structure sizes and
# perform bounds checking.
KBUILD_CFLAGS += $(call cc-option, -fstrict-flex-arrays=3)
# disable invalid "can't wrap" optimizations for signed / pointers
KBUILD_CFLAGS += -fno-strict-overflow
# Make sure -fstack-check isn't enabled (like gentoo apparently did)
KBUILD_CFLAGS += -fno-stack-check
# conserve stack if available
ifdef CONFIG_CC_IS_GCC
KBUILD_CFLAGS += -fconserve-stack
endif
# change __FILE__ to the relative path from the srctree
KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
# include additional Makefiles when needed
include-y := scripts/Makefile.extrawarn
include-$(CONFIG_DEBUG_INFO) += scripts/Makefile.debug
include-$(CONFIG_DEBUG_INFO_BTF)+= scripts/Makefile.btf
include-$(CONFIG_KASAN) += scripts/Makefile.kasan
include-$(CONFIG_KCSAN) += scripts/Makefile.kcsan
include-$(CONFIG_KMSAN) += scripts/Makefile.kmsan
include-$(CONFIG_UBSAN) += scripts/Makefile.ubsan
include-$(CONFIG_KCOV) += scripts/Makefile.kcov
include-$(CONFIG_RANDSTRUCT) += scripts/Makefile.randstruct
include-$(CONFIG_GCC_PLUGINS) += scripts/Makefile.gcc-plugins
include $(addprefix $(srctree)/, $(include-y))
# scripts/Makefile.gcc-plugins is intentionally included last.
# Do not add $(call cc-option,...) below this line. When you build the kernel
# from the clean source tree, the GCC plugins do not exist at this point.
# Add user supplied CPPFLAGS, AFLAGS, CFLAGS and RUSTFLAGS as the last assignments
KBUILD_CPPFLAGS += $(KCPPFLAGS)
KBUILD_AFLAGS += $(KAFLAGS)
KBUILD_CFLAGS += $(KCFLAGS)
KBUILD_RUSTFLAGS += $(KRUSTFLAGS)
KBUILD_LDFLAGS_MODULE += --build-id=sha1
LDFLAGS_vmlinux += --build-id=sha1
KBUILD_LDFLAGS += -z noexecstack
ifeq ($(CONFIG_LD_IS_BFD),y)
KBUILD_LDFLAGS += $(call ld-option,--no-warn-rwx-segments)
endif
ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
LDFLAGS_vmlinux += -X
endif
ifeq ($(CONFIG_RELR),y)
# ld.lld before 15 did not support -z pack-relative-relocs.
LDFLAGS_vmlinux += $(call ld-option,--pack-dyn-relocs=relr,-z pack-relative-relocs)
endif
# We never want expected sections to be placed heuristically by the
# linker. All sections should be explicitly named in the linker script.
ifdef CONFIG_LD_ORPHAN_WARN
LDFLAGS_vmlinux += --orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL)
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
PHONY += prepare0
export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
export MODORDER := $(extmod_prefix)modules.order
export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
ifeq ($(KBUILD_EXTMOD),)
build-dir := .
clean-dirs := $(sort . Documentation \
$(patsubst %/,%,$(filter %/, $(core-) \
$(drivers-) $(libs-))))
export ARCH_CORE := $(core-y)
export ARCH_LIB := $(filter %/, $(libs-y))
export ARCH_DRIVERS := $(drivers-y) $(drivers-m)
# Externally visible symbols (used by link-vmlinux.sh)
KBUILD_VMLINUX_OBJS := ./built-in.a
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, $(libs-y))
endif
export KBUILD_VMLINUX_LIBS
export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
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.
KBUILD_MODULES := 1
endif
# '$(AR) mPi' needs 'T' to workaround the bug of llvm-ar <= 14
quiet_cmd_ar_vmlinux.a = AR $@
cmd_ar_vmlinux.a = \
rm -f $@; \
$(AR) cDPrST $@ $(KBUILD_VMLINUX_OBJS); \
$(AR) mPiT $$($(AR) t $@ | sed -n 1p) $@ $$($(AR) t $@ | grep -F -f $(srctree)/scripts/head-object-list.txt)
targets += vmlinux.a
vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt FORCE
$(call if_changed,ar_vmlinux.a)
PHONY += vmlinux_o
vmlinux_o: vmlinux.a $(KBUILD_VMLINUX_LIBS)
$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux_o
vmlinux.o modules.builtin.modinfo modules.builtin: vmlinux_o
@:
PHONY += vmlinux
# LDFLAGS_vmlinux in the top Makefile defines linker flags for the top vmlinux,
# not for decompressors. LDFLAGS_vmlinux in arch/*/boot/compressed/Makefile is
# unrelated; the decompressors just happen to have the same base name,
# arch/*/boot/compressed/vmlinux.
# Export LDFLAGS_vmlinux only to scripts/Makefile.vmlinux.
#
# _LDFLAGS_vmlinux is a workaround for the 'private export' bug:
# https://savannah.gnu.org/bugs/?61463
# For Make > 4.4, the following simple code will work:
# vmlinux: private export LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
vmlinux: private _LDFLAGS_vmlinux := $(LDFLAGS_vmlinux)
vmlinux: export LDFLAGS_vmlinux = $(_LDFLAGS_vmlinux)
vmlinux: vmlinux.o $(KBUILD_LDS) modpost
$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vmlinux
# The actual objects are generated when descending,
# make sure no implicit rule kicks in
$(sort $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)): . ;
ifeq ($(origin KERNELRELEASE),file)
filechk_kernel.release = $(srctree)/scripts/setlocalversion $(srctree)
else
filechk_kernel.release = echo $(KERNELRELEASE)
endif
# 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) include/generated/utsrelease.h \
include/generated/compile.h include/generated/autoconf.h remove-stale-files
prepare0: archprepare
$(Q)$(MAKE) $(build)=scripts/mod
$(Q)$(MAKE) $(build)=. prepare
# All the preparing..
prepare: prepare0
ifdef CONFIG_RUST
$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh
$(Q)$(MAKE) $(build)=rust
endif
PHONY += remove-stale-files
remove-stale-files:
$(Q)$(srctree)/scripts/remove-stale-files
# 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
# 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
if [ $(SUBLEVEL) -gt 255 ]; then \
echo \#define LINUX_VERSION_CODE $(shell \
expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
else \
echo \#define LINUX_VERSION_CODE $(shell \
expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
fi; \
echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + \
((c) > 255 ? 255 : (c)))'; \
echo \#define LINUX_VERSION_MAJOR $(VERSION); \
echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL); \
echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
endef
$(version_h): PATCHLEVEL := $(or $(PATCHLEVEL), 0)
$(version_h): SUBLEVEL := $(or $(SUBLEVEL), 0)
$(version_h): FORCE
$(call filechk,version.h)
include/generated/utsrelease.h: include/config/kernel.release FORCE
$(call filechk,utsrelease.h)
filechk_compile.h = $(srctree)/scripts/mkcompile_h \
"$(UTS_MACHINE)" "$(CONFIG_CC_VERSION_TEXT)" "$(LD)"
include/generated/compile.h: FORCE
$(call filechk,compile.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 $(filter um, $(SRCARCH)), $(error Headers not exportable for UML))
$(Q)$(MAKE) $(hdr-inst)=include/uapi
$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
ifdef CONFIG_HEADERS_INSTALL
prepare: headers
endif
PHONY += scripts_unifdef
scripts_unifdef: scripts_basic
$(Q)$(MAKE) $(build)=scripts scripts/unifdef
# ---------------------------------------------------------------------------
# Install
# Many distributions have the custom install script, /sbin/installkernel.
# If DKMS is installed, 'make install' will eventually recurse back
# to this Makefile to build and install external modules.
# Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
quiet_cmd_install = INSTALL $(INSTALL_PATH)
cmd_install = unset sub_make_done; $(srctree)/scripts/install.sh
# ---------------------------------------------------------------------------
# vDSO install
PHONY += vdso_install
vdso_install: export INSTALL_FILES = $(vdso-install-y)
vdso_install:
$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.vdsoinst
# ---------------------------------------------------------------------------
# Tools
ifdef CONFIG_OBJTOOL
prepare: tools/objtool
endif
ifdef CONFIG_BPF
ifdef CONFIG_DEBUG_INFO_BTF
prepare: tools/bpf/resolve_btfids
endif
endif
PHONY += resolve_btfids_clean
resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
# tools/bpf/resolve_btfids directory might not exist
# in output directory, skip its clean in that case
resolve_btfids_clean:
ifneq ($(wildcard $(resolve_btfids_O)),)
$(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
endif
# 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/ $*
# ---------------------------------------------------------------------------
# Kernel selftest
PHONY += kselftest
kselftest: headers
$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
kselftest-%: headers 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 $(srctree)/tools/testing/selftests -name config -o -name config.$(UTS_MACHINE) | \
xargs $(srctree)/scripts/kconfig/merge_config.sh -y -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: dtbs_prepare
$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
%.dtbo: dtbs_prepare
$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
PHONY += dtbs dtbs_prepare dtbs_install dtbs_check
dtbs: dtbs_prepare
$(Q)$(MAKE) $(build)=$(dtstree)
# include/config/kernel.release is actually needed when installing DTBs because
# INSTALL_DTBS_PATH contains $(KERNELRELEASE). However, we do not want to make
# dtbs_install depend on it as dtbs_install may run as root.
dtbs_prepare: include/config/kernel.release scripts_dtc
ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
export CHECK_DTBS=y
endif
ifneq ($(CHECK_DTBS),)
dtbs_prepare: 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
PHONY += dt_compatible_check
dt_compatible_check: dt_binding_check
$(Q)$(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
#
# *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFO_BTF_MODULES
# is an exception.
ifdef CONFIG_DEBUG_INFO_BTF_MODULES
KBUILD_BUILTIN := 1
modules: vmlinux
endif
modules: modules_prepare
# Target to prepare building external modules
modules_prepare: prepare
$(Q)$(MAKE) $(build)=scripts scripts/module.lds
endif # CONFIG_MODULES
###
# Cleaning is done on three levels.
# make clean Delete most generated files
# Leave enough to build external modules
# make mrproper Delete the current configuration, and all generated files
# make distclean Remove editor backup files, patch leftover files and the like
# Directories & files removed with 'make clean'
CLEAN_FILES += vmlinux.symvers modules-only.symvers \
modules.builtin modules.builtin.modinfo modules.nsdeps \
compile_commands.json .thinlto-cache rust/test \
rust-project.json .vmlinux.objs .vmlinux.export.c
# Directories & files removed with 'make mrproper'
MRPROPER_FILES += include/config include/generated \
arch/$(SRCARCH)/include/generated .objdiff \
debian snap tar-install \
.config .config.old .version \
Module.symvers \
certs/signing_key.pem \
certs/x509.genkey \
vmlinux-gdb.py \
rpmbuild \
rust/libmacros.so
# 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 resolve_btfids_clean
# 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)
@find . $(RCS_FIND_IGNORE) \
\( -name '*.rmeta' \) \
-type f -print | xargs rm -f
# distclean
#
PHONY += distclean
distclean: mrproper
@find . $(RCS_FIND_IGNORE) \
\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
-o -name '*.bak' -o -name '#*#' -o -name '*%' \
-o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
-o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
-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 $(board-dirs:/=)))
PHONY += help
help:
@echo 'Cleaning targets:'
@echo ' clean - Remove most generated files but keep the config and'
@echo ' enough build support to build external modules'
@echo ' mrproper - Remove all generated files + config + various backup files'
@echo ' distclean - mrproper + remove editor backup and patch files'
@echo ''
@$(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 ' vdso_install - Install unstripped vdso 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: $(INSTALL_HDR_PATH))'; \
echo ''
@echo 'Static analysers:'
@echo ' checkstack - Generate a list of stack hogs'
@echo ' versioncheck - Sanity check on version.h usage'
@echo ' includecheck - Check for duplicate included header files'
@echo ' export_report - List the usages of all exported symbols'
@echo ' headerdep - Detect inclusion cycles in headers'
@echo ' coccicheck - Check with Coccinelle'
@echo ' clang-analyzer - Check with clang static analyzer'
@echo ' clang-tidy - Check with clang-tidy'
@echo ''
@echo 'Tools:'
@echo ' nsdeps - Generate missing symbol namespace dependencies'
@echo ''
@echo 'Kernel selftest:'
@echo ' kselftest - Build and run kernel selftest'
@echo ' Build, install, and boot kernel before'
@echo ' running kselftest on it'
@echo ' Run as root for full coverage'
@echo ' kselftest-all - Build kernel selftest'
@echo ' kselftest-install - Build and install kernel selftest'
@echo ' kselftest-clean - Remove all generated kselftest files'
@echo ' kselftest-merge - Merge all the config dependencies of'
@echo ' kselftest to existing .config.'
@echo ''
@echo 'Rust targets:'
@echo ' rustavailable - Checks whether the Rust toolchain is'
@echo ' available and, if not, explains why.'
@echo ' rustfmt - Reformat all the Rust code in the kernel'
@echo ' rustfmtcheck - Checks if all the Rust code in the kernel'
@echo ' is formatted, printing a diff otherwise.'
@echo ' rustdoc - Generate Rust documentation'
@echo ' (requires kernel .config)'
@echo ' rusttest - Runs the Rust tests'
@echo ' (requires kernel .config; downloads external repos)'
@echo ' rust-analyzer - Generate rust-project.json rust-analyzer support file'
@echo ' (requires kernel .config)'
@echo ' dir/file.[os] - Build specified target only'
@echo ' dir/file.rsi - Build macro expanded source, similar to C preprocessing.'
@echo ' Run with RUSTFMT=n to skip reformatting if needed.'
@echo ' The output is not intended to be compilable.'
@echo ' dir/file.ll - Build the LLVM assembly file'
@echo ''
@$(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)):'
@$(or $(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=n [targets] 1: verbose build'
@echo ' 2: give reason for rebuild of target'
@echo ' V=1 and V=2 can be combined with V=12'
@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 ' e: warnings are being treated as errors'
@echo ' Multiple levels can be combined with W=12 or W=123'
@$(if $(dtstree), \
echo ' make CHECK_DTBS=1 [targets] Check all generated dtb files against schema'; \
echo ' This can be applied both to "dtbs" and to individual "foo.dtb" targets' ; \
)
@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 texinfodocs infodocs
PHONY += $(DOC_TARGETS)
$(DOC_TARGETS):
$(Q)$(MAKE) $(build)=Documentation $@
# Rust targets
# ---------------------------------------------------------------------------
# "Is Rust available?" target
PHONY += rustavailable
rustavailable:
$(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh && echo "Rust is available!"
# Documentation target
#
# Using the singular to avoid running afoul of `no-dot-config-targets`.
PHONY += rustdoc
rustdoc: prepare
$(Q)$(MAKE) $(build)=rust $@
# Testing target
PHONY += rusttest
rusttest: prepare
$(Q)$(MAKE) $(build)=rust $@
# Formatting targets
PHONY += rustfmt rustfmtcheck
# We skip `rust/alloc` since we want to minimize the diff w.r.t. upstream.
#
# We match using absolute paths since `find` does not resolve them
# when matching, which is a problem when e.g. `srctree` is `..`.
# We `grep` afterwards in order to remove the directory entry itself.
rustfmt:
$(Q)find $(abs_srctree) -type f -name '*.rs' \
-o -path $(abs_srctree)/rust/alloc -prune \
-o -path $(abs_objtree)/rust/test -prune \
| grep -Fv $(abs_srctree)/rust/alloc \
| grep -Fv $(abs_objtree)/rust/test \
| grep -Fv generated \
| xargs $(RUSTFMT) $(rustfmt_flags)
rustfmtcheck: rustfmt_flags = --check
rustfmtcheck: rustfmt
# Misc
# ---------------------------------------------------------------------------
PHONY += misc-check
misc-check:
$(Q)$(srctree)/scripts/misc-check
all: misc-check
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
filechk_kernel.release = echo $(KERNELRELEASE)
###
# 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.
# We are always building only modules.
KBUILD_BUILTIN :=
KBUILD_MODULES := 1
build-dir := $(KBUILD_EXTMOD)
compile_commands.json: $(extmod_prefix)compile_commands.json
PHONY += compile_commands.json
clean-dirs := $(KBUILD_EXTMOD)
clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
$(KBUILD_EXTMOD)/compile_commands.json $(KBUILD_EXTMOD)/.thinlto-cache
PHONY += prepare
# now expand this into a simple variable to reduce the cost of shell evaluations
prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT)
prepare:
@if [ "$(CC_VERSION_TEXT)" != "$(CONFIG_CC_VERSION_TEXT)" ]; then \
echo >&2 "warning: the compiler differs from the one used to build the kernel"; \
echo >&2 " The kernel was built by: $(CONFIG_CC_VERSION_TEXT)"; \
echo >&2 " You are using: $(CC_VERSION_TEXT)"; \
fi
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 ' rust-analyzer - generate rust-project.json rust-analyzer support file'
@echo ''
ifndef CONFIG_MODULES
modules modules_install: __external_modules_error
__external_modules_error:
@echo >&2 '***'
@echo >&2 '*** The present kernel disabled CONFIG_MODULES.'
@echo >&2 '*** You cannot build or install external modules.'
@echo >&2 '***'
@false
endif
endif # KBUILD_EXTMOD
# ---------------------------------------------------------------------------
# Modules
PHONY += modules modules_install modules_sign modules_prepare
modules_install:
$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst \
sign-only=$(if $(filter modules_install,$(MAKECMDGOALS)),,y)
ifeq ($(CONFIG_MODULE_SIG),y)
# modules_sign is a subset of modules_install.
# 'make modules_install modules_sign' is equivalent to 'make modules_install'.
modules_sign: modules_install
@:
else
modules_sign:
@echo >&2 '***'
@echo >&2 '*** CONFIG_MODULE_SIG is disabled. You cannot sign modules.'
@echo >&2 '***'
@false
endif
ifdef CONFIG_MODULES
$(MODORDER): $(build-dir)
@:
# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
# This is solely useful to speed up test compiles.
modules: modpost
ifneq ($(KBUILD_MODPOST_NOFINAL),1)
$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
endif
PHONY += modules_check
modules_check: $(MODORDER)
$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
else # CONFIG_MODULES
modules:
@:
KBUILD_MODULES :=
endif # CONFIG_MODULES
PHONY += modpost
modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \
$(if $(KBUILD_MODULES), modules_check)
$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
# 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 := $(filter-out $(single-ko), $(MAKECMDGOALS)) \
$(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko)))
$(single-ko): single_modules
@:
$(single-no-ko): $(build-dir)
@:
# Remove MODORDER when done because it is not the real one.
PHONY += single_modules
single_modules: $(single-no-ko) modules_prepare
$(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$(m:%.ko=%.o);) } > $(MODORDER)
$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
ifneq ($(KBUILD_MODPOST_NOFINAL),1)
$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
endif
$(Q)rm -f $(MODORDER)
single-goals := $(addprefix $(build-dir)/, $(single-no-ko))
KBUILD_MODULES := 1
endif
# 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 += $(build-dir)
$(build-dir): prepare
$(Q)$(MAKE) $(build)=$@ need-builtin=1 need-modorder=1 $(single-goals)
clean-dirs := $(addprefix _clean_, $(clean-dirs))
PHONY += $(clean-dirs) clean
$(clean-dirs):
$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
clean: $(clean-dirs)
$(call cmd,rmfiles)
@find $(or $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
\( -name '*.[aios]' -o -name '*.rsi' -o -name '*.ko' -o -name '.*.cmd' \
-o -name '*.ko.*' \
-o -name '*.dtb' -o -name '*.dtbo' \
-o -name '*.dtb.S' -o -name '*.dtbo.S' \
-o -name '*.dt.yaml' \
-o -name '*.dwo' -o -name '*.lst' \
-o -name '*.su' -o -name '*.mod' \
-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
-o -name '*.lex.c' -o -name '*.tab.[ch]' \
-o -name '*.asn1.[ch]' \
-o -name '*.symtypes' -o -name 'modules.order' \
-o -name '*.c.[012]*.*' \
-o -name '*.ll' \
-o -name '*.gcno' \
-o -name '*.*.symversions' \) -type f -print \
-o -name '.tmp_*' -print \
| xargs rm -rf
# Generate tags for editors
# ---------------------------------------------------------------------------
quiet_cmd_tags = GEN $@
cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
tags TAGS cscope gtags: FORCE
$(call cmd,tags)
# IDE support targets
PHONY += rust-analyzer
rust-analyzer:
$(Q)$(MAKE) $(build)=rust $@
# Script to generate missing namespace dependencies
# ---------------------------------------------------------------------------
PHONY += nsdeps
nsdeps: export KBUILD_NSDEPS=1
nsdeps: modules
$(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
# Clang Tooling
# ---------------------------------------------------------------------------
quiet_cmd_gen_compile_commands = GEN $@
cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
$(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
$(if $(KBUILD_EXTMOD),, vmlinux.a $(KBUILD_VMLINUX_LIBS)) \
$(if $(CONFIG_MODULES), $(MODORDER)) FORCE
$(call if_changed,gen_compile_commands)
targets += $(extmod_prefix)compile_commands.json
PHONY += clang-tidy clang-analyzer
ifdef CONFIG_CC_IS_CLANG
quiet_cmd_clang_tools = CHECK $<
cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
$(call cmd,clang_tools)
else
clang-tidy clang-analyzer:
@echo "$@ requires CC=clang" >&2
@false
endif
# Scripts to check various things for consistency
# ---------------------------------------------------------------------------
PHONY += includecheck versioncheck coccicheck 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) $(srctree)/scripts/$@
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 $(CHECKSTACK_ARCH)
kernelrelease:
@$(filechk_kernel.release)
kernelversion:
@echo $(KERNELVERSION)
image_name:
@echo $(KBUILD_IMAGE)
PHONY += run-command
run-command:
$(Q)$(KBUILD_RUN_COMMAND)
quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
cmd_rmfiles = rm -rf $(rm-files)
# 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)
|