Merge tag 'kbuild-v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - Support cross-compiling linux-headers Debian package and kernel-devel
   RPM package

 - Add support for the linux-debug Pacman package

 - Improve module rebuilding speed by factoring out the common code to
   scripts/module-common.c

 - Separate device tree build rules into scripts/Makefile.dtbs

 - Add a new script to generate modules.builtin.ranges, which is useful
   for tracing tools to find symbols in built-in modules

 - Refactor Kconfig and misc tools

 - Update Kbuild and Kconfig documentation

* tag 'kbuild-v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (51 commits)
  kbuild: doc: replace "gcc" in external module description
  kbuild: doc: describe the -C option precisely for external module builds
  kbuild: doc: remove the description about shipped files
  kbuild: doc: drop section numbering, use references in modules.rst
  kbuild: doc: throw out the local table of contents in modules.rst
  kbuild: doc: remove outdated description of the limitation on -I usage
  kbuild: doc: remove description about grepping CONFIG options
  kbuild: doc: update the description about Kbuild/Makefile split
  kbuild: remove unnecessary export of RUST_LIB_SRC
  kbuild: remove append operation on cmd_ld_ko_o
  kconfig: cache expression values
  kconfig: use hash table to reuse expressions
  kconfig: refactor expr_eliminate_dups()
  kconfig: add comments to expression transformations
  kconfig: change some expr_*() functions to bool
  scripts: move hash function from scripts/kconfig/ to scripts/include/
  kallsyms: change overflow variable to bool type
  kallsyms: squash output_address()
  kbuild: add install target for modules.builtin.ranges
  scripts: add verifier script for builtin module range data
  ...

6 files changed, 87 insertions, 162 deletions

diff --git a/Documentation/dontdiff b/Documentation/dontdiff
index 94b3492dc301..de2cb8de6112 100644
--- a/Documentation/dontdiff
+++ b/Documentation/dontdiff
@@ -180,6 +180,7 @@ modpost
 modules-only.symvers
 modules.builtin
 modules.builtin.modinfo
+modules.builtin.ranges
 modules.nsdeps
 modules.order
 modversions.h*
diff --git a/Documentation/kbuild/kbuild.rst b/Documentation/kbuild/kbuild.rst
index 9c8d1d046ea5..1796b3eba37b 100644
--- a/Documentation/kbuild/kbuild.rst
+++ b/Documentation/kbuild/kbuild.rst
@@ -22,6 +22,11 @@ modules.builtin.modinfo
 This file contains modinfo from all modules that are built into the kernel.
 Unlike modinfo of a separate module, all fields are prefixed with module name.
 
+modules.builtin.ranges
+----------------------
+This file contains address offset ranges (per ELF section) for all modules
+that are built into the kernel. Together with System.map, it can be used
+to associate module names with symbols.
 
 Environment variables
 =====================
@@ -129,6 +134,11 @@ KBUILD_OUTPUT
 -------------
 Specify the output directory when building the kernel.
 
+This variable can also be used to point to the kernel output directory when
+building external modules against a pre-built kernel in a separate build
+directory. Please note that this does NOT specify the output directory for the
+external modules themselves.
+
 The output directory can also be specified using "O=...".
 
 Setting "O=..." takes precedence over KBUILD_OUTPUT.
diff --git a/Documentation/kbuild/kconfig-language.rst b/Documentation/kbuild/kconfig-language.rst
index 71b38a7670f3..43037be96a16 100644
--- a/Documentation/kbuild/kconfig-language.rst
+++ b/Documentation/kbuild/kconfig-language.rst
@@ -70,7 +70,11 @@ applicable everywhere (see syntax).
 
   Every menu entry can have at most one prompt, which is used to display
   to the user. Optionally dependencies only for this prompt can be added
-  with "if".
+  with "if". If a prompt is not present, the config option is a non-visible
+  symbol, meaning its value cannot be directly changed by the user (such as
+  altering the value in ``.config``) and the option will not appear in any
+  config menus. Its value can only be set via "default" and "select" (see
+  below).
 
 - default value: "default" <expr> ["if" <expr>]
 
diff --git a/Documentation/kbuild/makefiles.rst b/Documentation/kbuild/makefiles.rst
index be43990f1e7f..7964e0c245ae 100644
--- a/Documentation/kbuild/makefiles.rst
+++ b/Documentation/kbuild/makefiles.rst
@@ -1665,6 +1665,5 @@ Credits
 TODO
 ====
 
-- Describe how kbuild supports shipped files with _shipped.
 - Generating offset header files.
 - Add more variables to chapters 7 or 9?
diff --git a/Documentation/kbuild/modules.rst b/Documentation/kbuild/modules.rst
index 131863142cbb..cd5a54d91e6d 100644
--- a/Documentation/kbuild/modules.rst
+++ b/Documentation/kbuild/modules.rst
@@ -4,41 +4,12 @@ Building External Modules
 
 This document describes how to build an out-of-tree kernel module.
 
-.. Table of Contents
-
-	=== 1 Introduction
-	=== 2 How to Build External Modules
-	   --- 2.1 Command Syntax
-	   --- 2.2 Options
-	   --- 2.3 Targets
-	   --- 2.4 Building Separate Files
-	=== 3. Creating a Kbuild File for an External Module
-	   --- 3.1 Shared Makefile
-	   --- 3.2 Separate Kbuild file and Makefile
-	   --- 3.3 Binary Blobs
-	   --- 3.4 Building Multiple Modules
-	=== 4. Include Files
-	   --- 4.1 Kernel Includes
-	   --- 4.2 Single Subdirectory
-	   --- 4.3 Several Subdirectories
-	=== 5. Module Installation
-	   --- 5.1 INSTALL_MOD_PATH
-	   --- 5.2 INSTALL_MOD_DIR
-	=== 6. Module Versioning
-	   --- 6.1 Symbols From the Kernel (vmlinux + modules)
-	   --- 6.2 Symbols and External Modules
-	   --- 6.3 Symbols From Another External Module
-	=== 7. Tips & Tricks
-	   --- 7.1 Testing for CONFIG_FOO_BAR
-
-
-
-1. Introduction
-===============
+Introduction
+============
 
 "kbuild" is the build system used by the Linux kernel. Modules must use
 kbuild to stay compatible with changes in the build infrastructure and
-to pick up the right flags to "gcc." Functionality for building modules
+to pick up the right flags to the compiler. Functionality for building modules
 both in-tree and out-of-tree is provided. The method for building
 either is similar, and all modules are initially developed and built
 out-of-tree.
@@ -48,11 +19,11 @@ in building out-of-tree (or "external") modules. The author of an
 external module should supply a makefile that hides most of the
 complexity, so one only has to type "make" to build the module. This is
 easily accomplished, and a complete example will be presented in
-section 3.
+section `Creating a Kbuild File for an External Module`_.
 
 
-2. How to Build External Modules
-================================
+How to Build External Modules
+=============================
 
 To build external modules, you must have a prebuilt kernel available
 that contains the configuration and header files used in the build.
@@ -69,12 +40,12 @@ NOTE: "modules_prepare" will not build Module.symvers even if
 CONFIG_MODVERSIONS is set; therefore, a full kernel build needs to be
 executed to make module versioning work.
 
-2.1 Command Syntax
-==================
+Command Syntax
+--------------
 
 	The command to build an external module is::
 
-		$ make -C <path_to_kernel_src> M=$PWD
+		$ make -C <path_to_kernel_dir> M=$PWD
 
 	The kbuild system knows that an external module is being built
 	due to the "M=<dir>" option given in the command.
@@ -88,15 +59,18 @@ executed to make module versioning work.
 
 		$ make -C /lib/modules/`uname -r`/build M=$PWD modules_install
 
-2.2 Options
-===========
+Options
+-------
 
-	($KDIR refers to the path of the kernel source directory.)
+	($KDIR refers to the path of the kernel source directory, or the path
+	of the kernel output directory if the kernel was built in a separate
+	build directory.)
 
 	make -C $KDIR M=$PWD
 
 	-C $KDIR
-		The directory where the kernel source is located.
+		The directory that contains the kernel and relevant build
+		artifacts used for building an external module.
 		"make" will actually change to the specified directory
 		when executing and will change back when finished.
 
@@ -106,8 +80,8 @@ executed to make module versioning work.
 		directory where the external module (kbuild file) is
 		located.
 
-2.3 Targets
-===========
+Targets
+-------
 
 	When building an external module, only a subset of the "make"
 	targets are available.
@@ -129,7 +103,8 @@ executed to make module versioning work.
 	modules_install
 		Install the external module(s). The default location is
 		/lib/modules/<kernel_release>/updates/, but a prefix may
-		be added with INSTALL_MOD_PATH (discussed in section 5).
+		be added with INSTALL_MOD_PATH (discussed in section
+		`Module Installation`_).
 
 	clean
 		Remove all generated files in the module directory only.
@@ -137,8 +112,8 @@ executed to make module versioning work.
 	help
 		List the available targets for external modules.
 
-2.4 Building Separate Files
-===========================
+Building Separate Files
+-----------------------
 
 	It is possible to build single files that are part of a module.
 	This works equally well for the kernel, a module, and even for
@@ -152,8 +127,8 @@ executed to make module versioning work.
 		make -C $KDIR M=$PWD ./
 
 
-3. Creating a Kbuild File for an External Module
-================================================
+Creating a Kbuild File for an External Module
+=============================================
 
 In the last section we saw the command to build a module for the
 running kernel. The module is not actually built, however, because a
@@ -180,10 +155,9 @@ module 8123.ko, which is built from the following files::
 	8123_if.c
 	8123_if.h
 	8123_pci.c
-	8123_bin.o_shipped	<= Binary blob
 
-3.1 Shared Makefile
--------------------
+Shared Makefile
+---------------
 
 	An external module always includes a wrapper makefile that
 	supports building the module using "make" with no arguments.
@@ -198,7 +172,7 @@ module 8123.ko, which is built from the following files::
 		ifneq ($(KERNELRELEASE),)
 		# kbuild part of makefile
 		obj-m  := 8123.o
-		8123-y := 8123_if.o 8123_pci.o 8123_bin.o
+		8123-y := 8123_if.o 8123_pci.o
 
 		else
 		# normal makefile
@@ -207,10 +181,6 @@ module 8123.ko, which is built from the following files::
 		default:
 			$(MAKE) -C $(KDIR) M=$$PWD
 
-		# Module specific targets
-		genbin:
-			echo "X" > 8123_bin.o_shipped
-
 		endif
 
 	The check for KERNELRELEASE is used to separate the two parts
@@ -221,19 +191,18 @@ module 8123.ko, which is built from the following files::
 	line; the second pass is by the kbuild system, which is
 	initiated by the parameterized "make" in the default target.
 
-3.2 Separate Kbuild File and Makefile
--------------------------------------
+Separate Kbuild File and Makefile
+---------------------------------
 
-	In newer versions of the kernel, kbuild will first look for a
-	file named "Kbuild," and only if that is not found, will it
-	then look for a makefile. Utilizing a "Kbuild" file allows us
-	to split up the makefile from example 1 into two files:
+	Kbuild will first look for a file named "Kbuild", and if it is not
+	found, it will then look for "Makefile". Utilizing a "Kbuild" file
+	allows us to split up the "Makefile" from example 1 into two files:
 
 	Example 2::
 
 		--> filename: Kbuild
 		obj-m  := 8123.o
-		8123-y := 8123_if.o 8123_pci.o 8123_bin.o
+		8123-y := 8123_if.o 8123_pci.o
 
 		--> filename: Makefile
 		KDIR ?= /lib/modules/`uname -r`/build
@@ -241,68 +210,13 @@ module 8123.ko, which is built from the following files::
 		default:
 			$(MAKE) -C $(KDIR) M=$$PWD
 
-		# Module specific targets
-		genbin:
-			echo "X" > 8123_bin.o_shipped
-
 	The split in example 2 is questionable due to the simplicity of
 	each file; however, some external modules use makefiles
 	consisting of several hundred lines, and here it really pays
 	off to separate the kbuild part from the rest.
 
-	The next example shows a backward compatible version.
-
-	Example 3::
-
-		--> filename: Kbuild
-		obj-m  := 8123.o
-		8123-y := 8123_if.o 8123_pci.o 8123_bin.o
-
-		--> filename: Makefile
-		ifneq ($(KERNELRELEASE),)
-		# kbuild part of makefile
-		include Kbuild
-
-		else
-		# normal makefile
-		KDIR ?= /lib/modules/`uname -r`/build
-
-		default:
-			$(MAKE) -C $(KDIR) M=$$PWD
-
-		# Module specific targets
-		genbin:
-			echo "X" > 8123_bin.o_shipped
-
-		endif
-
-	Here the "Kbuild" file is included from the makefile. This
-	allows an older version of kbuild, which only knows of
-	makefiles, to be used when the "make" and kbuild parts are
-	split into separate files.
-
-3.3 Binary Blobs
-----------------
-
-	Some external modules need to include an object file as a blob.
-	kbuild has support for this, but requires the blob file to be
-	named <filename>_shipped. When the kbuild rules kick in, a copy
-	of <filename>_shipped is created with _shipped stripped off,
-	giving us <filename>. This shortened filename can be used in
-	the assignment to the module.
-
-	Throughout this section, 8123_bin.o_shipped has been used to
-	build the kernel module 8123.ko; it has been included as
-	8123_bin.o::
-
-		8123-y := 8123_if.o 8123_pci.o 8123_bin.o
-
-	Although there is no distinction between the ordinary source
-	files and the binary file, kbuild will pick up different rules
-	when creating the object file for the module.
-
-3.4 Building Multiple Modules
-=============================
+Building Multiple Modules
+-------------------------
 
 	kbuild supports building multiple modules with a single build
 	file. For example, if you wanted to build two modules, foo.ko
@@ -315,8 +229,8 @@ module 8123.ko, which is built from the following files::
 	It is that simple!
 
 
-4. Include Files
-================
+Include Files
+=============
 
 Within the kernel, header files are kept in standard locations
 according to the following rule:
@@ -334,19 +248,19 @@ according to the following rule:
 	      include/scsi; and architecture specific headers are located
 	      under arch/$(SRCARCH)/include/.
 
-4.1 Kernel Includes
--------------------
+Kernel Includes
+---------------
 
 	To include a header file located under include/linux/, simply
 	use::
 
 		#include <linux/module.h>
 
-	kbuild will add options to "gcc" so the relevant directories
+	kbuild will add options to the compiler so the relevant directories
 	are searched.
 
-4.2 Single Subdirectory
------------------------
+Single Subdirectory
+-------------------
 
 	External modules tend to place header files in a separate
 	include/ directory where their source is located, although this
@@ -360,15 +274,11 @@ according to the following rule:
 		--> filename: Kbuild
 		obj-m := 8123.o
 
-		ccflags-y := -Iinclude
-		8123-y := 8123_if.o 8123_pci.o 8123_bin.o
-
-	Note that in the assignment there is no space between -I and
-	the path. This is a limitation of kbuild: there must be no
-	space present.
+		ccflags-y := -I $(src)/include
+		8123-y := 8123_if.o 8123_pci.o
 
-4.3 Several Subdirectories
---------------------------
+Several Subdirectories
+----------------------
 
 	kbuild can handle files that are spread over several directories.
 	Consider the following example::
@@ -407,8 +317,8 @@ according to the following rule:
 	file is located.
 
 
-5. Module Installation
-======================
+Module Installation
+===================
 
 Modules which are included in the kernel are installed in the
 directory:
@@ -419,8 +329,8 @@ And external modules are installed in:
 
 	/lib/modules/$(KERNELRELEASE)/updates/
 
-5.1 INSTALL_MOD_PATH
---------------------
+INSTALL_MOD_PATH
+----------------
 
 	Above are the default directories but as always some level of
 	customization is possible. A prefix can be added to the
@@ -434,8 +344,8 @@ And external modules are installed in:
 	calling "make." This has effect when installing both in-tree
 	and out-of-tree modules.
 
-5.2 INSTALL_MOD_DIR
--------------------
+INSTALL_MOD_DIR
+---------------
 
 	External modules are by default installed to a directory under
 	/lib/modules/$(KERNELRELEASE)/updates/, but you may wish to
@@ -448,8 +358,8 @@ And external modules are installed in:
 		=> Install dir: /lib/modules/$(KERNELRELEASE)/gandalf/
 
 
-6. Module Versioning
-====================
+Module Versioning
+=================
 
 Module versioning is enabled by the CONFIG_MODVERSIONS tag, and is used
 as a simple ABI consistency check. A CRC value of the full prototype
@@ -461,8 +371,8 @@ module.
 Module.symvers contains a list of all exported symbols from a kernel
 build.
 
-6.1 Symbols From the Kernel (vmlinux + modules)
------------------------------------------------
+Symbols From the Kernel (vmlinux + modules)
+-------------------------------------------
 
 	During a kernel build, a file named Module.symvers will be
 	generated. Module.symvers contains all exported symbols from
@@ -486,8 +396,8 @@ build.
 	1) It lists all exported symbols from vmlinux and all modules.
 	2) It lists the CRC if CONFIG_MODVERSIONS is enabled.
 
-6.2 Symbols and External Modules
---------------------------------
+Symbols and External Modules
+----------------------------
 
 	When building an external module, the build system needs access
 	to the symbols from the kernel to check if all external symbols
@@ -496,8 +406,8 @@ build.
 	tree. During the MODPOST step, a new Module.symvers file will be
 	written containing all exported symbols from that external module.
 
-6.3 Symbols From Another External Module
-----------------------------------------
+Symbols From Another External Module
+------------------------------------
 
 	Sometimes, an external module uses exported symbols from
 	another external module. Kbuild needs to have full knowledge of
@@ -537,11 +447,11 @@ build.
 		initialization of its symbol tables.
 
 
-7. Tips & Tricks
-================
+Tips & Tricks
+=============
 
-7.1 Testing for CONFIG_FOO_BAR
-------------------------------
+Testing for CONFIG_FOO_BAR
+--------------------------
 
 	Modules often need to check for certain `CONFIG_` options to
 	decide if a specific feature is included in the module. In
@@ -553,9 +463,3 @@ build.
 
 		ext2-y := balloc.o bitmap.o dir.o
 		ext2-$(CONFIG_EXT2_FS_XATTR) += xattr.o
-
-	External modules have traditionally used "grep" to check for
-	specific `CONFIG_` settings directly in .config. This usage is
-	broken. As introduced before, external modules should use
-	kbuild for building and can therefore use the same methods as
-	in-tree modules when testing for `CONFIG_` definitions.
diff --git a/Documentation/process/changes.rst b/Documentation/process/changes.rst
index 3fc63f27c226..00f1ed7c59c3 100644
--- a/Documentation/process/changes.rst
+++ b/Documentation/process/changes.rst
@@ -64,6 +64,7 @@ GNU tar                1.28             tar --version
 gtags (optional)       6.6.5            gtags --version
 mkimage (optional)     2017.01          mkimage --version
 Python (optional)      3.5.x            python3 --version
+GNU AWK (optional)     5.1.0            gawk --version
 ====================== ===============  ========================================
 
 .. [#f1] Sphinx is needed only to build the Kernel documentation
@@ -192,6 +193,12 @@ platforms. The tool is available via the ``u-boot-tools`` package or can be
 built from the U-Boot source code. See the instructions at
 https://docs.u-boot.org/en/latest/build/tools.html#building-tools-for-linux
 
+GNU AWK
+-------
+
+GNU AWK is needed if you want kernel builds to generate address range data for
+builtin modules (CONFIG_BUILTIN_MODULE_RANGES).
+
 System utilities
 ****************