Merge tag 'kbuild-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - Add HOSTPKG_CONFIG env variable to allow users to override pkg-config

 - Support W=e as a shorthand for KCFLAGS=-Werror

 - Fix CONFIG_IKHEADERS build to support toybox cpio

 - Add scripts/dummy-tools/pahole to ease distro packagers' life

 - Suppress false-positive warnings from checksyscalls.sh for W=2 build

 - Factor out the common code of arch/*/boot/install.sh into
   scripts/install.sh

 - Support 'kernel-install' tool in scripts/prune-kernel

 - Refactor module-versioning to link the symbol versions at the final
   link of vmlinux and modules

 - Remove CONFIG_MODULE_REL_CRCS because module-versioning now works in
   an arch-agnostic way

 - Refactor modpost, Makefiles

* tag 'kbuild-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (56 commits)
  genksyms: adjust the output format to modpost
  kbuild: stop merging *.symversions
  kbuild: link symbol CRCs at final link, removing CONFIG_MODULE_REL_CRCS
  modpost: extract symbol versions from *.cmd files
  modpost: add sym_find_with_module() helper
  modpost: change the license of EXPORT_SYMBOL to bool type
  modpost: remove left-over cross_compile declaration
  kbuild: record symbol versions in *.cmd files
  kbuild: generate a list of objects in vmlinux
  modpost: move *.mod.c generation to write_mod_c_files()
  modpost: merge add_{intree_flag,retpoline,staging_flag} to add_header
  scripts/prune-kernel: Use kernel-install if available
  kbuild: factor out the common installation code into scripts/install.sh
  modpost: split new_symbol() to symbol allocation and hash table addition
  modpost: make sym_add_exported() always allocate a new symbol
  modpost: make multiple export error
  modpost: dump Module.symvers in the same order of modules.order
  modpost: traverse the namespace_list in order
  modpost: use doubly linked list for dump_lists
  modpost: traverse unresolved symbols in order
  ...

Author: torvalds

.gitignore

@@ -45,6 +45,7 @@
 *.symversions
 *.tab.[ch]
 *.tar
+*.usyms
 *.xz
 *.zst
 Module.symvers

Documentation/kbuild/kconfig-language.rst

@@ -693,13 +693,17 @@ in documenting basic Kconfig syntax a more precise definition of Kconfig
 semantics is welcomed. One project deduced Kconfig semantics through
 the use of the xconfig configurator [1]_. Work should be done to confirm if
 the deduced semantics matches our intended Kconfig design goals.
+Another project formalized a denotational semantics of a core subset of
+the Kconfig language [10]_.
 
 Having well defined semantics can be useful for tools for practical
 evaluation of dependencies, for instance one such case was work to
 express in boolean abstraction of the inferred semantics of Kconfig to
 translate Kconfig logic into boolean formulas and run a SAT solver on this to
 find dead code / features (always inactive), 114 dead features were found in
 Linux using this methodology [1]_ (Section 8: Threats to validity).
+The kismet tool, based on the semantics in [10]_, finds abuses of reverse
+dependencies and has led to dozens of committed fixes to Linux Kconfig files [11]_.
 
 Confirming this could prove useful as Kconfig stands as one of the leading
 industrial variability modeling languages [1]_ [2]_. Its study would help
@@ -738,3 +742,5 @@ https://kernelnewbies.org/KernelProjects/kconfig-sat
 .. [7] https://vamos.cs.fau.de
 .. [8] https://undertaker.cs.fau.de
 .. [9] https://www4.cs.fau.de/Publications/2011/tartler_11_eurosys.pdf
+.. [10] https://paulgazzillo.com/papers/esecfse21.pdf
+.. [11] https://github.com/paulgazz/kmax

Makefile

@@ -436,6 +436,7 @@ else
 HOSTCC	= gcc
 HOSTCXX	= g++
 endif
+HOSTPKG_CONFIG	= pkg-config
 
 KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
 			 -O2 -fomit-frame-pointer -std=gnu11 \
@@ -533,7 +534,7 @@ KBUILD_LDFLAGS_MODULE :=
 KBUILD_LDFLAGS :=
 CLANG_FLAGS :=
 
-export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC
+export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG
 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
@@ -1294,11 +1295,12 @@ scripts_unifdef: scripts_basic
 # Install
 
 # Many distributions have the custom install script, /sbin/installkernel.
-# If DKMS is installed, 'make install' will eventually recuses back
-# to the this Makefile to build and install external modules.
+# 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.
 
-install: sub_make_done :=
+quiet_cmd_install = INSTALL $(INSTALL_PATH)
+      cmd_install = unset sub_make_done; $(srctree)/scripts/install.sh
 
 # ---------------------------------------------------------------------------
 # Tools
@@ -1650,6 +1652,7 @@ help:
 	@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'
 	@echo  ''
 	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
@@ -1792,7 +1795,8 @@ 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-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \
+		$(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko)))
 
 $(single-ko): single_modpost
 	@:
@@ -1848,7 +1852,7 @@ clean: $(clean-dirs)
 		-o -name '*.ko.*' \
 		-o -name '*.dtb' -o -name '*.dtbo' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
 		-o -name '*.dwo' -o -name '*.lst' \
-		-o -name '*.su' -o -name '*.mod' \
+		-o -name '*.su' -o -name '*.mod' -o -name '*.usyms' \
 		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
 		-o -name '*.lex.c' -o -name '*.tab.[ch]' \
 		-o -name '*.asn1.[ch]' \

arch/arm/Makefile

@@ -312,9 +312,9 @@ $(BOOT_TARGETS): vmlinux
 	$(Q)$(MAKE) $(build)=$(boot) MACHINE=$(MACHINE) $(boot)/$@
 	@$(kecho) '  Kernel: $(boot)/$@ is ready'
 
+$(INSTALL_TARGETS): KBUILD_IMAGE = $(boot)/$(patsubst %install,%Image,$@)
 $(INSTALL_TARGETS):
-	$(CONFIG_SHELL) $(srctree)/$(boot)/install.sh "$(KERNELRELEASE)" \
-	$(boot)/$(patsubst %install,%Image,$@) System.map "$(INSTALL_PATH)"
+	$(call cmd,install)
 
 PHONY += vdso_install
 vdso_install:

arch/arm/boot/install.sh

@@ -1,7 +1,5 @@
 #!/bin/sh
 #
-# arch/arm/boot/install.sh
-#
 # This file is subject to the terms and conditions of the GNU General Public
 # License.  See the file "COPYING" in the main directory of this archive
 # for more details.
@@ -18,25 +16,6 @@
 #   $2 - kernel image file
 #   $3 - kernel map file
 #   $4 - default install path (blank if root directory)
-#
-
-verify () {
-	if [ ! -f "$1" ]; then
-		echo ""                                                   1>&2
-		echo " *** Missing file: $1"                              1>&2
-		echo ' *** You need to run "make" before "make install".' 1>&2
-		echo ""                                                   1>&2
-		exit 1
-	fi
-}
-
-# Make sure the files actually exist
-verify "$2"
-verify "$3"
-
-# User may have a custom install script
-if [ -x ~/bin/${INSTALLKERNEL} ]; then exec ~/bin/${INSTALLKERNEL} "$@"; fi
-if [ -x /sbin/${INSTALLKERNEL} ]; then exec /sbin/${INSTALLKERNEL} "$@"; fi
 
 if [ "$(basename $2)" = "zImage" ]; then
 # Compressed install

arch/arm64/Makefile

@@ -162,11 +162,9 @@ Image: vmlinux
 Image.%: Image
 	$(Q)$(MAKE) $(build)=$(boot) $(boot)/$@
 
-install: install-image := Image
-zinstall: install-image := Image.gz
+install: KBUILD_IMAGE := $(boot)/Image
 install zinstall:
-	$(CONFIG_SHELL) $(srctree)/$(boot)/install.sh $(KERNELRELEASE) \
-	$(boot)/$(install-image) System.map "$(INSTALL_PATH)"
+	$(call cmd,install)
 
 PHONY += vdso_install
 vdso_install:

arch/arm64/boot/install.sh

@@ -1,7 +1,5 @@
 #!/bin/sh
 #
-# arch/arm64/boot/install.sh
-#
 # This file is subject to the terms and conditions of the GNU General Public
 # License.  See the file "COPYING" in the main directory of this archive
 # for more details.
@@ -18,25 +16,6 @@
 #   $2 - kernel image file
 #   $3 - kernel map file
 #   $4 - default install path (blank if root directory)
-#
-
-verify () {
-	if [ ! -f "$1" ]; then
-		echo ""                                                   1>&2
-		echo " *** Missing file: $1"                              1>&2
-		echo ' *** You need to run "make" before "make install".' 1>&2
-		echo ""                                                   1>&2
-		exit 1
-	fi
-}
-
-# Make sure the files actually exist
-verify "$2"
-verify "$3"
-
-# User may have a custom install script
-if [ -x ~/bin/${INSTALLKERNEL} ]; then exec ~/bin/${INSTALLKERNEL} "$@"; fi
-if [ -x /sbin/${INSTALLKERNEL} ]; then exec /sbin/${INSTALLKERNEL} "$@"; fi
 
 if [ "$(basename $2)" = "Image.gz" ]; then
 # Compressed install

arch/ia64/Makefile

@@ -72,8 +72,9 @@ archheaders:
 
 CLEAN_FILES += vmlinux.gz
 
-install: vmlinux.gz
-	sh $(srctree)/arch/ia64/install.sh $(KERNELRELEASE) $< System.map "$(INSTALL_PATH)"
+install: KBUILD_IMAGE := vmlinux.gz
+install:
+	$(call cmd,install)
 
 define archhelp
   echo '* compressed	- Build compressed kernel image'

arch/ia64/install.sh

@@ -1,7 +1,5 @@
 #!/bin/sh
 #
-# arch/ia64/install.sh
-#
 # This file is subject to the terms and conditions of the GNU General Public
 # License.  See the file "COPYING" in the main directory of this archive
 # for more details.
@@ -17,14 +15,6 @@
 #   $2 - kernel image file
 #   $3 - kernel map file
 #   $4 - default install path (blank if root directory)
-#
-
-# User may have a custom install script
-
-if [ -x ~/bin/${INSTALLKERNEL} ]; then exec ~/bin/${INSTALLKERNEL} "$@"; fi
-if [ -x /sbin/${INSTALLKERNEL} ]; then exec /sbin/${INSTALLKERNEL} "$@"; fi
-
-# Default install - same as make zlilo
 
 if [ -f $4/vmlinuz ]; then
 	mv $4/vmlinuz $4/vmlinuz.old

arch/m68k/Makefile

@@ -138,5 +138,6 @@ CLEAN_FILES += vmlinux.gz vmlinux.bz2
 archheaders:
 	$(Q)$(MAKE) $(build)=arch/m68k/kernel/syscalls all
 
+install: KBUILD_IMAGE := vmlinux.gz
 install:
-	sh $(srctree)/arch/m68k/install.sh $(KERNELRELEASE) vmlinux.gz System.map "$(INSTALL_PATH)"
+	$(call cmd,install)