Merge tag 'kbuild-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - Evaluate $(call cc-option,...) etc. only for build targets

 - Add CONFIG_VMLINUX_MAP to generate .map file when linking vmlinux

 - Remove unnecessary --gcc-toolchains Clang flag because the --prefix
   flag finds the toolchains

 - Do not pass Clang's --prefix flag when using the integrated as

 - Check the assembler version in Kconfig time

 - Add new CONFIG options, AS_VERSION, AS_IS_GNU, AS_IS_LLVM to clean up
   some dependencies in Kconfig

 - Fix invalid Module.symvers creation when building only modules
   without vmlinux

 - Fix false-positive modpost warnings when CONFIG_TRIM_UNUSED_KSYMS is
   set, but there is no module to build

 - Refactor module installation Makefile

 - Support zstd for module compression

 - Convert alpha and ia64 to use generic shell scripts to generate the
   syscall headers

 - Add a new elfnote to indicate if the kernel was built with LTO, which
   will be used by pahole

 - Flatten the directory structure under include/config/ so CONFIG
   options and filenames match

 - Change the deb source package name from linux-$(KERNELRELEASE) to
   linux-upstream

* tag 'kbuild-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (42 commits)
  kbuild: Add $(KBUILD_HOSTLDFLAGS) to 'has_libelf' test
  kbuild: deb-pkg: change the source package name to linux-upstream
  tools: do not include scripts/Kbuild.include
  kbuild: redo fake deps at include/config/*.h
  kbuild: remove TMPO from try-run
  MAINTAINERS: add pattern for dummy-tools
  kbuild: add an elfnote for whether vmlinux is built with lto
  ia64: syscalls: switch to generic syscallhdr.sh
  ia64: syscalls: switch to generic syscalltbl.sh
  alpha: syscalls: switch to generic syscallhdr.sh
  alpha: syscalls: switch to generic syscalltbl.sh
  sysctl: use min() helper for namecmp()
  kbuild: add support for zstd compressed modules
  kbuild: remove CONFIG_MODULE_COMPRESS
  kbuild: merge scripts/Makefile.modsign to scripts/Makefile.modinst
  kbuild: move module strip/compression code into scripts/Makefile.modinst
  kbuild: refactor scripts/Makefile.modinst
  kbuild: rename extmod-prefix to extmod_prefix
  kbuild: check module name conflict for external modules as well
  kbuild: show the target directory for depmod log
  ...

1 files changed, 45 insertions, 20 deletions

diff --git a/init/Kconfig b/init/Kconfig
index ca559ccdaa32..d97d205cd1ef 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -21,7 +21,7 @@ config CC_VERSION_TEXT
 
 	  - Ensure full rebuild when the compiler is updated
 	    include/linux/compiler-version.h contains this option in the comment
-	    line so fixdep adds include/config/cc/version/text.h into the
+	    line so fixdep adds include/config/CC_VERSION_TEXT into the
 	    auto-generated dependency. When the compiler is updated, syncconfig
 	    will touch it and then every file will be rebuilt.
 
@@ -41,6 +41,18 @@ config CLANG_VERSION
 	default $(cc-version) if CC_IS_CLANG
 	default 0
 
+config AS_IS_GNU
+	def_bool $(success,test "$(as-name)" = GNU)
+
+config AS_IS_LLVM
+	def_bool $(success,test "$(as-name)" = LLVM)
+
+config AS_VERSION
+	int
+	# Use clang version if this is the integrated assembler
+	default CLANG_VERSION if AS_IS_LLVM
+	default $(as-version)
+
 config LD_IS_BFD
 	def_bool $(success,test "$(ld-name)" = BFD)
 
@@ -2229,40 +2241,53 @@ config MODULE_SIG_HASH
 	default "sha384" if MODULE_SIG_SHA384
 	default "sha512" if MODULE_SIG_SHA512
 
-config MODULE_COMPRESS
-	bool "Compress modules on installation"
+choice
+	prompt "Module compression mode"
 	help
+	  This option allows you to choose the algorithm which will be used to
+	  compress modules when 'make modules_install' is run. (or, you can
+	  choose to not compress modules at all.)
 
-	  Compresses kernel modules when 'make modules_install' is run; gzip or
-	  xz depending on "Compression algorithm" below.
+	  External modules will also be compressed in the same way during the
+	  installation.
 
-	  module-init-tools MAY support gzip, and kmod MAY support gzip and xz.
+	  For modules inside an initrd or initramfs, it's more efficient to
+	  compress the whole initrd or initramfs instead.
 
-	  Out-of-tree kernel modules installed using Kbuild will also be
-	  compressed upon installation.
+	  This is fully compatible with signed modules.
 
-	  Note: for modules inside an initrd or initramfs, it's more efficient
-	  to compress the whole initrd or initramfs instead.
+	  Please note that the tool used to load modules needs to support the
+	  corresponding algorithm. module-init-tools MAY support gzip, and kmod
+	  MAY support gzip, xz and zstd.
 
-	  Note: This is fully compatible with signed modules.
+	  Your build system needs to provide the appropriate compression tool
+	  to compress the modules.
 
-	  If in doubt, say N.
+	  If in doubt, select 'None'.
 
-choice
-	prompt "Compression algorithm"
-	depends on MODULE_COMPRESS
-	default MODULE_COMPRESS_GZIP
+config MODULE_COMPRESS_NONE
+	bool "None"
 	help
-	  This determines which sort of compression will be used during
-	  'make modules_install'.
-
-	  GZIP (default) and XZ are supported.
+	  Do not compress modules. The installed modules are suffixed
+	  with .ko.
 
 config MODULE_COMPRESS_GZIP
 	bool "GZIP"
+	help
+	  Compress modules with GZIP. The installed modules are suffixed
+	  with .ko.gz.
 
 config MODULE_COMPRESS_XZ
 	bool "XZ"
+	help
+	  Compress modules with XZ. The installed modules are suffixed
+	  with .ko.xz.
+
+config MODULE_COMPRESS_ZSTD
+	bool "ZSTD"
+	help
+	  Compress modules with ZSTD. The installed modules are suffixed
+	  with .ko.zst.
 
 endchoice