Kbuild updates for v5.7

[Build system]
 
  - add CONFIG_UNUSED_KSYMS_WHITELIST, which will be useful to define
    a fixed set of export symbols for Generic Kernel Image (GKI)
 
  - allow to run 'make dt_binding_check' without .config
 
  - use full schema for checking DT examples in *.yaml files
 
  - make modpost fail for missing MODULE_IMPORT_NS(), which makes more
    sense because we know the produced modules are never loadable
 
  - Remove unused 'AS' variable
 
 [Kconfig]
 
  - sanitize DEFCONFIG_LIST, and remove ARCH_DEFCONFIG from Kconfig files
 
  - relax the 'imply' behavior so that symbols implied by y can become m
 
  - make 'imply' obey 'depends on' in order to make 'imply' really weak
 
 [Misc]
 
  - add documentation on building the kernel with Clang/LLVM
 
  - revive __HAVE_ARCH_STRLEN for 32bit sparc to use optimized strlen()
 
  - fix warning from deb-pkg builds when CONFIG_DEBUG_INFO=n
 
  - various script and Makefile cleanups
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Merge tag 'kbuild-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:
 "Build system:

   - add CONFIG_UNUSED_KSYMS_WHITELIST, which will be useful to define a
     fixed set of export symbols for Generic Kernel Image (GKI)

   - allow to run 'make dt_binding_check' without .config

   - use full schema for checking DT examples in *.yaml files

   - make modpost fail for missing MODULE_IMPORT_NS(), which makes more
     sense because we know the produced modules are never loadable

   - Remove unused 'AS' variable

  Kconfig:

   - sanitize DEFCONFIG_LIST, and remove ARCH_DEFCONFIG from Kconfig
     files

   - relax the 'imply' behavior so that symbols implied by 'y' can
     become 'm'

   - make 'imply' obey 'depends on' in order to make 'imply' really weak

  Misc:

   - add documentation on building the kernel with Clang/LLVM

   - revive __HAVE_ARCH_STRLEN for 32bit sparc to use optimized strlen()

   - fix warning from deb-pkg builds when CONFIG_DEBUG_INFO=n

   - various script and Makefile cleanups"

* tag 'kbuild-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (34 commits)
  Makefile: Update kselftest help information
  kbuild: deb-pkg: fix warning when CONFIG_DEBUG_INFO is unset
  kbuild: add outputmakefile to no-dot-config-targets
  kbuild: remove AS variable
  net: wan: wanxl: refactor the firmware rebuild rule
  net: wan: wanxl: use $(M68KCC) instead of $(M68KAS) for rebuilding firmware
  net: wan: wanxl: use allow to pass CROSS_COMPILE_M68k for rebuilding firmware
  kbuild: add comment about grouped target
  kbuild: add -Wall to KBUILD_HOSTCXXFLAGS
  kconfig: remove unused variable in qconf.cc
  sparc: revive __HAVE_ARCH_STRLEN for 32bit sparc
  kbuild: refactor Makefile.dtbinst more
  kbuild: compute the dtbs_install destination more simply
  Makefile: disallow data races on gcc-10 as well
  kconfig: make 'imply' obey the direct dependency
  kconfig: allow symbols implied by y to become m
  net: drop_monitor: use IS_REACHABLE() to guard net_dm_hw_report()
  modpost: return error if module is missing ns imports and MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS=n
  modpost: rework and consolidate logging interface
  kbuild: allow to run dt_binding_check without kernel configuration
  ...

Documentation/Makefile

@@ -2,7 +2,8 @@
 # Makefile for Sphinx documentation
 #
 
-subdir-y := devicetree/bindings/
+# for cleaning
+subdir- := devicetree/bindings
 
 # Check for broken documentation file references
 ifeq ($(CONFIG_WARN_MISSING_DOCUMENTS),y)

Documentation/devicetree/bindings/.gitignore

@@ -1,2 +1,2 @@
 *.example.dts
-processed-schema.yaml
+processed-schema*.yaml

Documentation/devicetree/bindings/Makefile

@@ -2,7 +2,6 @@
 DT_DOC_CHECKER ?= dt-doc-validate
 DT_EXTRACT_EX ?= dt-extract-example
 DT_MK_SCHEMA ?= dt-mk-schema
-DT_MK_SCHEMA_FLAGS := $(if $(DT_SCHEMA_FILES), -u)
 
 quiet_cmd_chk_binding = CHKDT   $(patsubst $(srctree)/%,%,$<)
       cmd_chk_binding = $(DT_DOC_CHECKER) -u $(srctree)/$(src) $< ; \
@@ -11,26 +10,35 @@ quiet_cmd_chk_binding = CHKDT   $(patsubst $(srctree)/%,%,$<)
 $(obj)/%.example.dts: $(src)/%.yaml FORCE
 	$(call if_changed,chk_binding)
 
-DT_TMP_SCHEMA := processed-schema.yaml
+# Use full schemas when checking %.example.dts
+DT_TMP_SCHEMA := $(obj)/processed-schema-examples.yaml
 
 quiet_cmd_mk_schema = SCHEMA  $@
       cmd_mk_schema = $(DT_MK_SCHEMA) $(DT_MK_SCHEMA_FLAGS) -o $@ $(real-prereqs)
 
-DT_DOCS = $(shell \
+DT_DOCS = $(addprefix $(src)/, \
+	$(shell \
 	cd $(srctree)/$(src) && \
 	find * \( -name '*.yaml' ! \
-		-name $(DT_TMP_SCHEMA) ! \
+		-name 'processed-schema*' ! \
 		-name '*.example.dt.yaml' \) \
-	)
+	))
 
-DT_SCHEMA_FILES ?= $(addprefix $(src)/,$(DT_DOCS))
+DT_SCHEMA_FILES ?= $(DT_DOCS)
 
-ifeq ($(CHECK_DTBS),)
+extra-$(CHECK_DT_BINDING) += $(patsubst $(src)/%.yaml,%.example.dts, $(DT_SCHEMA_FILES))
-extra-y += $(patsubst $(src)/%.yaml,%.example.dts, $(DT_SCHEMA_FILES))
+extra-$(CHECK_DT_BINDING) += $(patsubst $(src)/%.yaml,%.example.dt.yaml, $(DT_SCHEMA_FILES))
-extra-y += $(patsubst $(src)/%.yaml,%.example.dt.yaml, $(DT_SCHEMA_FILES))
+extra-$(CHECK_DT_BINDING) += processed-schema-examples.yaml
-endif
 
-$(obj)/$(DT_TMP_SCHEMA): $(DT_SCHEMA_FILES) FORCE
+override DTC_FLAGS := \
+	-Wno-avoid_unnecessary_addr_size \
+	-Wno-graph_child_address
+
+$(obj)/processed-schema-examples.yaml: $(DT_DOCS) FORCE
 	$(call if_changed,mk_schema)
 
-extra-y += $(DT_TMP_SCHEMA)
+$(obj)/processed-schema.yaml: DT_MK_SCHEMA_FLAGS := -u
+$(obj)/processed-schema.yaml: $(DT_SCHEMA_FILES) FORCE
+	$(call if_changed,mk_schema)
+
+extra-y += processed-schema.yaml

Documentation/devicetree/writing-schema.rst

@@ -147,6 +147,10 @@ Note that ``dtbs_check`` will skip any binding schema files with errors. It is
 necessary to use ``dt_binding_check`` to get all the validation errors in the
 binding schema files.
 
+It is possible to run both in a single command::
+
+    make dt_binding_check dtbs_check
+
 It is also possible to run checks with a single schema file by setting the
 ``DT_SCHEMA_FILES`` variable to a specific schema file.
 

Documentation/kbuild/index.rst

@@ -20,6 +20,7 @@ Kernel Build System
     issues
     reproducible-builds
     gcc-plugins
+    llvm
 
 .. only::  subproject and html
 

Documentation/kbuild/kconfig-language.rst

@@ -159,11 +159,11 @@ applicable everywhere (see syntax).
   Given the following example::
 
     config FOO
-	tristate
+	tristate "foo"
 	imply BAZ
 
     config BAZ
-	tristate
+	tristate "baz"
 	depends on BAR
 
   The following values are possible:
@@ -173,7 +173,10 @@ applicable everywhere (see syntax).
 	===		===		=============	==============
 	n		y		n		N/m/y
 	m		y		m		M/y/n
-	y		y		y		Y/n
+	y		y		y		Y/m/n
+	n		m		n		N/m
+	m		m		m		M/n
+	y		m		n		M/n
 	y		n		*		N
 	===		===		=============	==============
 
@@ -181,6 +184,24 @@ applicable everywhere (see syntax).
   ability to hook into a secondary subsystem while allowing the user to
   configure that subsystem out without also having to unset these drivers.
 
+  Note: If the combination of FOO=y and BAR=m causes a link error,
+  you can guard the function call with IS_REACHABLE()::
+
+	foo_init()
+	{
+		if (IS_REACHABLE(CONFIG_BAZ))
+			baz_register(&foo);
+		...
+	}
+
+  Note: If the feature provided by BAZ is highly desirable for FOO,
+  FOO should imply not only BAZ, but also its dependency BAR::
+
+    config FOO
+	tristate "foo"
+	imply BAR
+	imply BAZ
+
 - limiting menu display: "visible if" <expr>
 
   This attribute is only applicable to menu blocks, if the condition is

Documentation/kbuild/llvm.rst

@@ -0,0 +1,80 @@
+==============================
+Building Linux with Clang/LLVM
+==============================
+
+This document covers how to build the Linux kernel with Clang and LLVM
+utilities.
+
+About
+-----
+
+The Linux kernel has always traditionally been compiled with GNU toolchains
+such as GCC and binutils. Ongoing work has allowed for `Clang
+<https://clang.llvm.org/>`_ and `LLVM <https://llvm.org/>`_ utilities to be
+used as viable substitutes. Distributions such as `Android
+<https://www.android.com/>`_, `ChromeOS
+<https://www.chromium.org/chromium-os>`_, and `OpenMandriva
+<https://www.openmandriva.org/>`_ use Clang built kernels.  `LLVM is a
+collection of toolchain components implemented in terms of C++ objects
+<https://www.aosabook.org/en/llvm.html>`_. Clang is a front-end to LLVM that
+supports C and the GNU C extensions required by the kernel, and is pronounced
+"klang," not "see-lang."
+
+Clang
+-----
+
+The compiler used can be swapped out via `CC=` command line argument to `make`.
+`CC=` should be set when selecting a config and during a build.
+
+	make CC=clang defconfig
+
+	make CC=clang
+
+Cross Compiling
+---------------
+
+A single Clang compiler binary will typically contain all supported backends,
+which can help simplify cross compiling.
+
+	ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- make CC=clang
+
+`CROSS_COMPILE` is not used to prefix the Clang compiler binary, instead
+`CROSS_COMPILE` is used to set a command line flag: `--target <triple>`. For
+example:
+
+	clang --target aarch64-linux-gnu foo.c
+
+LLVM Utilities
+--------------
+
+LLVM has substitutes for GNU binutils utilities. These can be invoked as
+additional parameters to `make`.
+
+	make CC=clang AS=clang LD=ld.lld AR=llvm-ar NM=llvm-nm STRIP=llvm-strip \\
+	  OBJCOPY=llvm-objcopy OBJDUMP=llvm-objdump OBJSIZE=llvm-objsize \\
+	  READELF=llvm-readelf HOSTCC=clang HOSTCXX=clang++ HOSTAR=llvm-ar \\
+	  HOSTLD=ld.lld
+
+Getting Help
+------------
+
+- `Website <https://clangbuiltlinux.github.io/>`_
+- `Mailing List <https://groups.google.com/forum/#!forum/clang-built-linux>`_: <clang-built-linux@googlegroups.com>
+- `Issue Tracker <https://github.com/ClangBuiltLinux/linux/issues>`_
+- IRC: #clangbuiltlinux on chat.freenode.net
+- `Telegram <https://t.me/ClangBuiltLinux>`_: @ClangBuiltLinux
+- `Wiki <https://github.com/ClangBuiltLinux/linux/wiki>`_
+- `Beginner Bugs <https://github.com/ClangBuiltLinux/linux/issues?q=is%3Aopen+is%3Aissue+label%3A%22good+first+issue%22>`_
+
+Getting LLVM
+-------------
+
+- http://releases.llvm.org/download.html
+- https://github.com/llvm/llvm-project
+- https://llvm.org/docs/GettingStarted.html
+- https://llvm.org/docs/CMake.html
+- https://apt.llvm.org/
+- https://www.archlinux.org/packages/extra/x86_64/llvm/
+- https://github.com/ClangBuiltLinux/tc-build
+- https://github.com/ClangBuiltLinux/linux/wiki/Building-Clang-from-source
+- https://android.googlesource.com/platform/prebuilts/clang/host/linux-x86/

MAINTAINERS

@@ -4139,6 +4139,7 @@ B:	https://github.com/ClangBuiltLinux/linux/issues
 C:	irc://chat.freenode.net/clangbuiltlinux
 S:	Supported
 K:	\b(?i:clang|llvm)\b
+F:	Documentation/kbuild/llvm.rst
 
 CLEANCACHE API
 M:	Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Makefile

@@ -255,7 +255,8 @@ 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
+			 %asm-generic kernelversion %src-pkg dt_binding_check \
+			 outputmakefile
 no-sync-config-targets := $(no-dot-config-targets) install %install \
 			   kernelrelease
 single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
@@ -388,6 +389,9 @@ endif
 KCONFIG_CONFIG	?= .config
 export KCONFIG_CONFIG
 
+# Default file for 'make defconfig'. This may be overridden by arch-Makefile.
+export KBUILD_DEFCONFIG := defconfig
+
 # SHELL used by kbuild
 CONFIG_SHELL := sh
 
@@ -400,12 +404,11 @@ HOSTCXX      = g++
 KBUILD_HOSTCFLAGS   := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 \
 		-fomit-frame-pointer -std=gnu89 $(HOST_LFS_CFLAGS) \
 		$(HOSTCFLAGS)
-KBUILD_HOSTCXXFLAGS := -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
+KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
 KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
 KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
 
 # Make variables (CC, etc...)
-AS		= $(CROSS_COMPILE)as
 LD		= $(CROSS_COMPILE)ld
 CC		= $(CROSS_COMPILE)gcc
 CPP		= $(CC) -E
@@ -472,7 +475,7 @@ KBUILD_LDFLAGS :=
 GCC_PLUGINS_CFLAGS :=
 CLANG_FLAGS :=
 
-export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE AS LD CC
+export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC
 export CPP AR NM STRIP OBJCOPY OBJDUMP OBJSIZE READELF PAHOLE LEX YACC AWK INSTALLKERNEL
 export PERL PYTHON PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
 export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
@@ -535,7 +538,7 @@ endif
 ifneq ($(GCC_TOOLCHAIN),)
 CLANG_FLAGS	+= --gcc-toolchain=$(GCC_TOOLCHAIN)
 endif
-ifeq ($(shell $(AS) --version 2>&1 | head -n 1 | grep clang),)
+ifeq ($(if $(AS),$(shell $(AS) --version 2>&1 | head -n 1 | grep clang)),)
 CLANG_FLAGS	+= -no-integrated-as
 endif
 CLANG_FLAGS	+= -Werror=unknown-warning-option
@@ -674,6 +677,7 @@ $(KCONFIG_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)
 %/auto.conf %/auto.conf.cmd: $(KCONFIG_CONFIG)
 	$(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
 else # !may-sync-config
@@ -714,6 +718,7 @@ endif
 
 # Tell gcc to never replace conditional load with a non-conditional one
 KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
+KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
 
 include scripts/Makefile.kcov
 include scripts/Makefile.gcc-plugins
@@ -729,7 +734,7 @@ KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
 endif
 
 ifneq ($(CONFIG_FRAME_WARN),0)
-KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
+KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
 endif
 
 stackp-flags-$(CONFIG_CC_HAS_STACKPROTECTOR_NONE) := -fno-stack-protector
@@ -1063,9 +1068,12 @@ endif
 
 autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
 
+quiet_cmd_autoksyms_h = GEN     $@
+      cmd_autoksyms_h = mkdir -p $(dir $@); \
+			$(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@
+
 $(autoksyms_h):
-	$(Q)mkdir -p $(dir $@)
+	$(call cmd,autoksyms_h)
-	$(Q)touch $@
 
 ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
 
@@ -1240,14 +1248,18 @@ ifneq ($(dtstree),)
 	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
 
 PHONY += dtbs dtbs_install dtbs_check
-dtbs dtbs_check: include/config/kernel.release scripts_dtc
+dtbs: include/config/kernel.release scripts_dtc
 	$(Q)$(MAKE) $(build)=$(dtstree)
 
-dtbs_check: export CHECK_DTBS=1
+ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
-dtbs_check: dt_binding_check
+export CHECK_DTBS=y
+dtbs: dt_binding_check
+endif
+
+dtbs_check: dtbs
 
 dtbs_install:
-	$(Q)$(MAKE) $(dtbinst)=$(dtstree)
+	$(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
 
 ifdef CONFIG_OF_EARLY_FLATTREE
 all: dtbs
@@ -1259,6 +1271,10 @@ 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) $(build)=Documentation/devicetree/bindings
@@ -1470,12 +1486,15 @@ help:
 	@echo  '  nsdeps          - Generate missing symbol namespace dependencies'
 	@echo  ''
 	@echo  'Kernel selftest:'
-	@echo  '  kselftest       - Build and run kernel selftest (run as root)'
+	@echo  '  kselftest         - Build and run kernel selftest'
-	@echo  '                    Build, install, and boot kernel before'
+	@echo  '                      Build, install, and boot kernel before'
-	@echo  '                    running kselftest on it'
+	@echo  '                      running kselftest on it'
-	@echo  '  kselftest-clean - Remove all generated kselftest files'
+	@echo  '                      Run as root for full coverage'
-	@echo  '  kselftest-merge - Merge all the config dependencies of kselftest to existing'
+	@echo  '  kselftest-all     - Build kernel selftest'
-	@echo  '                    .config.'
+	@echo  '  kselftest-install - Build and install kernel selftest'
+	@echo  '  kselftest-clean   - Remove all generated kselftest files'
+	@echo  '  kselftest-merge   - Merge all the config dependencies of'
+	@echo  '		      kselftest to existing .config.'
 	@echo  ''
 	@$(if $(dtstree), \
 		echo 'Devicetree:'; \

arch/sh/Kconfig

@@ -87,11 +87,6 @@ config SUPERH64
 	select HAVE_EXIT_THREAD
 	select KALLSYMS
 
-config ARCH_DEFCONFIG
-	string
-	default "arch/sh/configs/shx3_defconfig" if SUPERH32
-	default "arch/sh/configs/cayman_defconfig" if SUPERH64
-
 config GENERIC_BUG
 	def_bool y
 	depends on BUG && SUPERH32

arch/sparc/Kconfig

@@ -96,11 +96,6 @@ config SPARC64
 	select PCI_DOMAINS if PCI
 	select ARCH_HAS_GIGANTIC_PAGE
 
-config ARCH_DEFCONFIG
-	string
-	default "arch/sparc/configs/sparc32_defconfig" if SPARC32
-	default "arch/sparc/configs/sparc64_defconfig" if SPARC64
-
 config ARCH_PROC_KCORE_TEXT
 	def_bool y
 

arch/sparc/include/asm/string.h

@@ -37,6 +37,10 @@ void *memmove(void *, const void *, __kernel_size_t);
 #define __HAVE_ARCH_MEMCMP
 int memcmp(const void *,const void *,__kernel_size_t);
 
+/* Now the str*() stuff... */
+#define __HAVE_ARCH_STRLEN
+__kernel_size_t strlen(const char *);
+
 #define __HAVE_ARCH_STRNCMP
 int strncmp(const char *, const char *, __kernel_size_t);
 

arch/sparc/include/asm/string_64.h

@@ -12,8 +12,4 @@
 
 #include <asm/asi.h>
 
-/* Now the str*() stuff... */
-#define __HAVE_ARCH_STRLEN
-__kernel_size_t strlen(const char *);
-
 #endif /* !(__SPARC64_STRING_H__) */

arch/x86/Kconfig

@@ -240,11 +240,6 @@ config OUTPUT_FORMAT
 	default "elf32-i386" if X86_32
 	default "elf64-x86-64" if X86_64
 
-config ARCH_DEFCONFIG
-	string
-	default "arch/x86/configs/i386_defconfig" if X86_32
-	default "arch/x86/configs/x86_64_defconfig" if X86_64
-
 config LOCKDEP_SUPPORT
 	def_bool y
 

arch/x86/um/Kconfig

@@ -27,11 +27,6 @@ config X86_64
 	def_bool 64BIT
 	select MODULES_USE_ELF_RELA
 
-config ARCH_DEFCONFIG
-	string
-	default "arch/um/configs/i386_defconfig" if X86_32
-	default "arch/um/configs/x86_64_defconfig" if X86_64
-
 config 3_LEVEL_PGTABLES
 	bool "Three-level pagetables" if !64BIT
 	default 64BIT

drivers/net/wan/Kconfig

@@ -200,7 +200,7 @@ config WANXL_BUILD_FIRMWARE
 	depends on WANXL && !PREVENT_FIRMWARE_BUILD
 	help
 	  Allows you to rebuild firmware run by the QUICC processor.
-	  It requires as68k, ld68k and hexdump programs.
+	  It requires m68k toolchains and hexdump programs.
 
 	  You should never need this option, say N.
 

drivers/net/wan/Makefile

@@ -40,21 +40,30 @@ $(obj)/wanxl.o:	$(obj)/wanxlfw.inc
 
 ifeq ($(CONFIG_WANXL_BUILD_FIRMWARE),y)
 ifeq ($(ARCH),m68k)
-  AS68K = $(AS)
+  M68KCC = $(CC)
-  LD68K = $(LD)
+  M68KLD = $(LD)
 else
-  AS68K = as68k
+  M68KCC = $(CROSS_COMPILE_M68K)gcc
-  LD68K = ld68k
+  M68KLD = $(CROSS_COMPILE_M68K)ld
 endif
 
-quiet_cmd_build_wanxlfw = BLD FW  $@
+quiet_cmd_build_wanxlfw = BLDFW   $@
-      cmd_build_wanxlfw = \
+      cmd_build_wanxlfw = hexdump -ve '"\n" 16/1 "0x%02X,"' $< | \
-	$(CPP) -D__ASSEMBLY__ -Wp,-MD,$(depfile) -I$(srctree)/include/uapi $< | $(AS68K) -m68360 -o $(obj)/wanxlfw.o; \
+	sed 's/0x  ,//g;1s/^/static const u8 firmware[]={/;$$s/,$$/\n};\n/' > $@
-	$(LD68K) --oformat binary -Ttext 0x1000 $(obj)/wanxlfw.o -o $(obj)/wanxlfw.bin; \
-	hexdump -ve '"\n" 16/1 "0x%02X,"' $(obj)/wanxlfw.bin | sed 's/0x  ,//g;1s/^/static const u8 firmware[]={/;$$s/,$$/\n};\n/' >$(obj)/wanxlfw.inc; \
-	rm -f $(obj)/wanxlfw.bin $(obj)/wanxlfw.o
 
-$(obj)/wanxlfw.inc:	$(src)/wanxlfw.S
+$(obj)/wanxlfw.inc: $(obj)/wanxlfw.bin FORCE
-	$(call if_changed_dep,build_wanxlfw)
+	$(call if_changed,build_wanxlfw)
-targets += wanxlfw.inc
+
+quiet_cmd_m68kld_bin_o = M68KLD  $@
+      cmd_m68kld_bin_o = $(M68KLD) --oformat binary -Ttext 0x1000 $< -o $@
+
+$(obj)/wanxlfw.bin: $(obj)/wanxlfw.o FORCE
+	$(call if_changed,m68kld_bin_o)
+
+quiet_cmd_m68kas_o_S = M68KAS  $@
+      cmd_m68kas_o_S = $(M68KCC) -D__ASSEMBLY__ -Wp,-MD,$(depfile) -I$(srctree)/include/uapi -c -o $@ $<
+
+$(obj)/wanxlfw.o: $(src)/wanxlfw.S FORCE
+	$(call if_changed_dep,m68kas_o_S)
 endif
+targets += wanxlfw.inc wanxlfw.bin wanxlfw.o

include/net/drop_monitor.h

@@ -19,7 +19,7 @@ struct net_dm_hw_metadata {
 	struct net_device *input_dev;
 };
 
-#if IS_ENABLED(CONFIG_NET_DROP_MONITOR)
+#if IS_REACHABLE(CONFIG_NET_DROP_MONITOR)
 void net_dm_hw_report(struct sk_buff *skb,
 		      const struct net_dm_hw_metadata *hw_metadata);
 #else

init/Kconfig

@@ -6,8 +6,7 @@ config DEFCONFIG_LIST
 	default "/lib/modules/$(shell,uname -r)/.config"
 	default "/etc/kernel-config"
 	default "/boot/config-$(shell,uname -r)"
-	default ARCH_DEFCONFIG
+	default "arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG)"
-	default "arch/$(ARCH)/defconfig"
 
 config CC_IS_GCC
 	def_bool $(success,$(CC) --version | head -n 1 | grep -q gcc)
@@ -2211,6 +2210,19 @@ config TRIM_UNUSED_KSYMS
 
 	  If unsure, or if you need to build out-of-tree modules, say N.
 
+config UNUSED_KSYMS_WHITELIST
+	string "Whitelist of symbols to keep in ksymtab"
+	depends on TRIM_UNUSED_KSYMS
+	help
+	  By default, all unused exported symbols will be un-exported from the
+	  build when TRIM_UNUSED_KSYMS is selected.
+
+	  UNUSED_KSYMS_WHITELIST allows to whitelist symbols that must be kept
+	  exported at all times, even in absence of in-tree users. The value to
+	  set here is the path to a text file containing the list of symbols,
+	  one per line. The path can be absolute, or relative to the kernel
+	  source tree.
+
 endif # MODULES
 
 config MODULES_TREE_LOOKUP

lib/Kconfig.debug

@@ -266,7 +266,7 @@ config ENABLE_MUST_CHECK
 	  attribute warn_unused_result" messages.
 
 config FRAME_WARN
-	int "Warn for stack frames larger than (needs gcc 4.4)"
+	int "Warn for stack frames larger than"
 	range 0 8192
 	default 2048 if GCC_PLUGIN_LATENT_ENTROPY
 	default 1280 if (!64BIT && PARISC)
@@ -276,7 +276,6 @@ config FRAME_WARN
 	  Tell gcc to warn at build time for stack frames larger than this.
 	  Setting this too low will cause a lot of warnings.
 	  Setting it to 0 disables the warning.
-	  Requires gcc 4.4
 
 config STRIP_ASM_SYMS
 	bool "Strip assembler-generated symbols during link"

scripts/Makefile.dtbinst

@@ -13,28 +13,24 @@ src := $(obj)
 PHONY := __dtbs_install
 __dtbs_install:
 
-export dtbinst_root ?= $(obj)
-
 include include/config/auto.conf
 include scripts/Kbuild.include
 include $(src)/Makefile
 
-dtbinst-files	:= $(sort $(dtb-y) $(if $(CONFIG_OF_ALL_DTBS), $(dtb-)))
+dtbs    := $(addprefix $(dst)/, $(dtb-y) $(if $(CONFIG_OF_ALL_DTBS),$(dtb-)))
-dtbinst-dirs	:= $(subdir-y) $(subdir-m)
+subdirs := $(addprefix $(obj)/, $(subdir-y) $(subdir-m))
 
-# Helper targets for Installing DTBs into the boot directory
+__dtbs_install: $(dtbs) $(subdirs)
-quiet_cmd_dtb_install =	INSTALL $<
+	@:
-      cmd_dtb_install =	mkdir -p $(2); cp $< $(2)
 
-install-dir = $(patsubst $(dtbinst_root)%,$(INSTALL_DTBS_PATH)%,$(obj))
+quiet_cmd_dtb_install = INSTALL $@
+      cmd_dtb_install = install -D $< $@
 
-$(dtbinst-files): %.dtb: $(obj)/%.dtb
+$(dst)/%.dtb: $(obj)/%.dtb
-	$(call cmd,dtb_install,$(install-dir))
+	$(call cmd,dtb_install)
 
-$(dtbinst-dirs):
+PHONY += $(subdirs)
-	$(Q)$(MAKE) $(dtbinst)=$(obj)/$@
+$(subdirs):
-
+	$(Q)$(MAKE) $(dtbinst)=$@ dst=$(patsubst $(obj)/%,$(dst)/%,$@)
-PHONY += $(dtbinst-files) $(dtbinst-dirs)
-__dtbs_install: $(dtbinst-files) $(dtbinst-dirs)
 
 .PHONY: $(PHONY)

scripts/Makefile.lib

@@ -297,7 +297,8 @@ $(obj)/%.dtb: $(src)/%.dts $(DTC) FORCE
 
 DT_CHECKER ?= dt-validate
 DT_BINDING_DIR := Documentation/devicetree/bindings
-DT_TMP_SCHEMA := $(objtree)/$(DT_BINDING_DIR)/processed-schema.yaml
+# DT_TMP_SCHEMA may be overridden from Documentation/devicetree/bindings/Makefile
+DT_TMP_SCHEMA ?= $(objtree)/$(DT_BINDING_DIR)/processed-schema.yaml
 
 quiet_cmd_dtb_check =	CHECK   $@
       cmd_dtb_check =	$(DT_CHECKER) -u $(srctree)/$(DT_BINDING_DIR) -p $(DT_TMP_SCHEMA) $@

scripts/Makefile.modpost

@@ -46,13 +46,14 @@ include scripts/Kbuild.include
 kernelsymfile := $(objtree)/Module.symvers
 modulesymfile := $(firstword $(KBUILD_EXTMOD))/Module.symvers
 
-MODPOST = scripts/mod/modpost						\
+MODPOST = scripts/mod/modpost								\
-	$(if $(CONFIG_MODVERSIONS),-m)					\
+	$(if $(CONFIG_MODVERSIONS),-m)							\
-	$(if $(CONFIG_MODULE_SRCVERSION_ALL),-a)			\
+	$(if $(CONFIG_MODULE_SRCVERSION_ALL),-a)					\
-	$(if $(KBUILD_EXTMOD),-i,-o) $(kernelsymfile)			\
+	$(if $(KBUILD_EXTMOD),-i,-o) $(kernelsymfile)					\
-	$(if $(KBUILD_EXTMOD),$(addprefix -e ,$(KBUILD_EXTRA_SYMBOLS)))	\
+	$(if $(KBUILD_EXTMOD),$(addprefix -e ,$(KBUILD_EXTRA_SYMBOLS)))			\
-	$(if $(KBUILD_EXTMOD),-o $(modulesymfile))			\
+	$(if $(KBUILD_EXTMOD),-o $(modulesymfile))					\
-	$(if $(CONFIG_SECTION_MISMATCH_WARN_ONLY),,-E)			\
+	$(if $(CONFIG_SECTION_MISMATCH_WARN_ONLY),,-E)					\
+	$(if $(CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS)$(KBUILD_NSDEPS),-N) 	\
 	$(if $(KBUILD_MODPOST_WARN),-w)
 
 ifdef MODPOST_VMLINUX

scripts/adjust_autoksyms.sh

@@ -1,14 +1,13 @@
 #!/bin/sh
 # SPDX-License-Identifier: GPL-2.0-only
 
-# Script to create/update include/generated/autoksyms.h and dependency files
+# Script to update include/generated/autoksyms.h and dependency files
 #
 # Copyright:	(C) 2016  Linaro Limited
 # Created by:	Nicolas Pitre, January 2016
 #
 
-# Create/update the include/generated/autoksyms.h file from the list
+# Update the include/generated/autoksyms.h file.
-# of all module's needed symbols as recorded on the second line of *.mod files.
 #
 # For each symbol being added or removed, the corresponding dependency
 # file's timestamp is updated to force a rebuild of the affected source
@@ -38,23 +37,8 @@ esac
 # We need access to CONFIG_ symbols
 . include/config/auto.conf
 
-# Generate a new ksym list file with symbols needed by the current
+# Generate a new symbol list file
-# set of modules.
+$CONFIG_SHELL $srctree/scripts/gen_autoksyms.sh "$new_ksyms_file"
-cat > "$new_ksyms_file" << EOT
-/*
- * Automatically generated file; DO NOT EDIT.
- */
-
-EOT
-sed 's/ko$/mod/' modules.order |
-xargs -n1 sed -n -e '2{s/ /\n/g;/^$/!p;}' -- |
-sort -u |
-sed -e 's/\(.*\)/#define __KSYM_\1 1/' >> "$new_ksyms_file"
-
-# Special case for modversions (see modpost.c)
-if [ -n "$CONFIG_MODVERSIONS" ]; then
-	echo "#define __KSYM_module_layout 1" >> "$new_ksyms_file"
-fi
 
 # Extract changes between old and new list and touch corresponding
 # dependency files.

scripts/basic/fixdep.c

@@ -77,11 +77,6 @@
  * dependencies on include/config/my/option.h for every
  * CONFIG_MY_OPTION encountered in any of the prerequisites.
  *
- * It will also filter out all the dependencies on *.ver. We need
- * to make sure that the generated version checksum are globally up
- * to date before even starting the recursive build, so it's too late
- * at this point anyway.
- *
  * We don't even try to really parse the header files, but
  * merely grep, i.e. if CONFIG_FOO is mentioned in a comment, it will
  * be picked up as well. It's not a problem with respect to
@@ -251,7 +246,7 @@ static void parse_config_file(const char *p)
 		}
 		p += 7;
 		q = p;
-		while (*q && (isalnum(*q) || *q == '_'))
+		while (isalnum(*q) || *q == '_')
 			q++;
 		if (str_ends_with(p, q - p, "_MODULE"))
 			r = q - 7;
@@ -299,8 +294,7 @@ static void *read_file(const char *filename)
 static int is_ignored_file(const char *s, int len)
 {
 	return str_ends_with(s, len, "include/generated/autoconf.h") ||
-	       str_ends_with(s, len, "include/generated/autoksyms.h") ||
+	       str_ends_with(s, len, "include/generated/autoksyms.h");
-	       str_ends_with(s, len, ".ver");
 }
 
 /*

scripts/dtc/Makefile

@@ -1,8 +1,9 @@
 # SPDX-License-Identifier: GPL-2.0
 # scripts/dtc makefile
 
-hostprogs		:= dtc
+hostprogs			:= dtc
-always-$(CONFIG_DTC)	:= $(hostprogs)
+always-$(CONFIG_DTC)		+= $(hostprogs)
+always-$(CHECK_DT_BINDING)	+= $(hostprogs)
 
 dtc-objs	:= dtc.o flattree.o fstree.o data.o livetree.o treesource.o \
 		   srcpos.o checks.o util.o

scripts/gcc-plugins/Makefile

@@ -10,7 +10,7 @@ else
   HOSTLIBS := hostcxxlibs
   HOST_EXTRACXXFLAGS += -I$(GCC_PLUGINS_DIR)/include -I$(src) -std=gnu++98 -fno-rtti
   HOST_EXTRACXXFLAGS += -fno-exceptions -fasynchronous-unwind-tables -ggdb
-  HOST_EXTRACXXFLAGS += -Wno-narrowing -Wno-unused-variable
+  HOST_EXTRACXXFLAGS += -Wno-narrowing -Wno-unused-variable -Wno-c++11-compat
   export HOST_EXTRACXXFLAGS
 endif
 

scripts/gen_autoksyms.sh

@@ -0,0 +1,52 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0-only
+
+# Create an autoksyms.h header file from the list of all module's needed symbols
+# as recorded on the second line of *.mod files and the user-provided symbol
+# whitelist.
+
+set -e
+
+output_file="$1"
+
+# Use "make V=1" to debug this script.
+case "$KBUILD_VERBOSE" in
+*1*)
+	set -x
+	;;
+esac
+
+# We need access to CONFIG_ symbols
+. include/config/auto.conf
+
+ksym_wl=/dev/null
+if [ -n "$CONFIG_UNUSED_KSYMS_WHITELIST" ]; then
+	# Use 'eval' to expand the whitelist path and check if it is relative
+	eval ksym_wl="$CONFIG_UNUSED_KSYMS_WHITELIST"
+	[ "${ksym_wl}" != "${ksym_wl#/}" ] || ksym_wl="$abs_srctree/$ksym_wl"
+	if [ ! -f "$ksym_wl" ] || [ ! -r "$ksym_wl" ]; then
+		echo "ERROR: '$ksym_wl' whitelist file not found" >&2
+		exit 1
+	fi
+fi
+
+# Generate a new ksym list file with symbols needed by the current
+# set of modules.
+cat > "$output_file" << EOT
+/*
+ * Automatically generated file; DO NOT EDIT.
+ */
+
+EOT
+
+[ -f modules.order ] && modlist=modules.order || modlist=/dev/null
+sed 's/ko$/mod/' $modlist |
+xargs -n1 sed -n -e '2{s/ /\n/g;/^$/!p;}' -- |
+cat - "$ksym_wl" |
+sort -u |
+sed -e 's/\(.*\)/#define __KSYM_\1 1/' >> "$output_file"
+
+# Special case for modversions (see modpost.c)
+if [ -n "$CONFIG_MODVERSIONS" ]; then
+	echo "#define __KSYM_module_layout 1" >> "$output_file"
+fi

scripts/kconfig/Makefile

@@ -12,10 +12,6 @@ else
 Kconfig := Kconfig
 endif
 
-ifndef KBUILD_DEFCONFIG
-KBUILD_DEFCONFIG := defconfig
-endif
-
 ifeq ($(quiet),silent_)
 silent := -s
 endif

scripts/kconfig/qconf.cc

@@ -309,8 +309,6 @@ ConfigList::ConfigList(ConfigView* p, const char *name)
 	  showName(false), showRange(false), showData(false), mode(singleMode), optMode(normalOpt),
 	  rootEntry(0), headerPopup(0)
 {
-	int i;
-
 	setObjectName(name);
 	setSortingEnabled(false);
 	setRootIsDecorated(true);

scripts/kconfig/symbol.c

@@ -221,7 +221,7 @@ static void sym_calc_visibility(struct symbol *sym)
 		sym_set_changed(sym);
 	}
 	tri = no;
-	if (sym->implied.expr && sym->dir_dep.tri != no)
+	if (sym->implied.expr)
 		tri = expr_calc_value(sym->implied.expr);
 	if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
 		tri = yes;
@@ -394,6 +394,8 @@ void sym_calc_value(struct symbol *sym)
 				if (sym->implied.tri != no) {
 					sym->flags |= SYMBOL_WRITE;
 					newval.tri = EXPR_OR(newval.tri, sym->implied.tri);
+					newval.tri = EXPR_AND(newval.tri,
+							      sym->dir_dep.tri);
 				}
 			}
 		calc_newval:
@@ -401,8 +403,7 @@ void sym_calc_value(struct symbol *sym)
 				sym_warn_unmet_dep(sym);
 			newval.tri = EXPR_OR(newval.tri, sym->rev_dep.tri);
 		}
-		if (newval.tri == mod &&
+		if (newval.tri == mod && sym_get_type(sym) == S_BOOLEAN)
-		    (sym_get_type(sym) == S_BOOLEAN || sym->implied.tri == yes))
 			newval.tri = yes;
 		break;
 	case S_STRING:
@@ -484,8 +485,6 @@ bool sym_tristate_within_range(struct symbol *sym, tristate val)
 		return false;
 	if (sym->visible <= sym->rev_dep.tri)
 		return false;
-	if (sym->implied.tri == yes && val == mod)
-		return false;
 	if (sym_is_choice_value(sym) && sym->visible == yes)
 		return val == yes;
 	return val >= sym->rev_dep.tri && val <= sym->visible;

scripts/mkcompile_h

@@ -10,17 +10,6 @@ CC=$6
 
 vecho() { [ "${quiet}" = "silent_" ] || echo "$@" ; }
 
-# If compile.h exists already and we don't own autoconf.h
-# (i.e. we're not the same user who did make *config), don't
-# modify compile.h
-# So "sudo make install" won't change the "compiled by <user>"
-# do "compiled by root"
-
-if [ -r $TARGET -a ! -O include/generated/autoconf.h ]; then
-  vecho "  SKIPPED $TARGET"
-  exit 0
-fi
-
 # Do not expand names
 set -f
 

scripts/mod/modpost.c

@@ -39,6 +39,8 @@ static int sec_mismatch_count = 0;
 static int sec_mismatch_fatal = 0;
 /* ignore missing files */
 static int ignore_missing_files;
+/* If set to 1, only warn (instead of error) about missing ns imports */
+static int allow_missing_ns_imports;
 
 enum export {
 	export_plain,      export_unused,     export_gpl,
@@ -51,41 +53,33 @@ enum export {
 
 #define MODULE_NAME_LEN (64 - sizeof(Elf_Addr))
 
-#define PRINTF __attribute__ ((format (printf, 1, 2)))
+void __attribute__((format(printf, 2, 3)))
-
+modpost_log(enum loglevel loglevel, const char *fmt, ...)
-PRINTF void fatal(const char *fmt, ...)
 {
 	va_list arglist;
 
-	fprintf(stderr, "FATAL: ");
+	switch (loglevel) {
+	case LOG_WARN:
+		fprintf(stderr, "WARNING: ");
+		break;
+	case LOG_ERROR:
+		fprintf(stderr, "ERROR: ");
+		break;
+	case LOG_FATAL:
+		fprintf(stderr, "FATAL: ");
+		break;
+	default: /* invalid loglevel, ignore */
+		break;
+	}
+
+	fprintf(stderr, "modpost: ");
 
 	va_start(arglist, fmt);
 	vfprintf(stderr, fmt, arglist);
 	va_end(arglist);
 
-	exit(1);
+	if (loglevel == LOG_FATAL)
-}
+		exit(1);
-
-PRINTF void warn(const char *fmt, ...)
-{
-	va_list arglist;
-
-	fprintf(stderr, "WARNING: ");
-
-	va_start(arglist, fmt);
-	vfprintf(stderr, fmt, arglist);
-	va_end(arglist);
-}
-
-PRINTF void merror(const char *fmt, ...)
-{
-	va_list arglist;
-
-	fprintf(stderr, "ERROR: ");
-
-	va_start(arglist, fmt);
-	vfprintf(stderr, fmt, arglist);
-	va_end(arglist);
 }
 
 static inline bool strends(const char *str, const char *postfix)
@@ -113,7 +107,7 @@ static int is_vmlinux(const char *modname)
 void *do_nofail(void *ptr, const char *expr)
 {
 	if (!ptr)
-		fatal("modpost: Memory allocation failure: %s.\n", expr);
+		fatal("Memory allocation failure: %s.\n", expr);
 
 	return ptr;
 }
@@ -2022,7 +2016,7 @@ static void read_symbols(const char *modname)
 
 	license = get_modinfo(&info, "license");
 	if (!license && !is_vmlinux(modname))
-		warn("modpost: missing MODULE_LICENSE() in %s\n"
+		warn("missing MODULE_LICENSE() in %s\n"
 		     "see include/linux/module.h for "
 		     "more information\n", modname);
 	while (license) {
@@ -2153,15 +2147,15 @@ static void check_for_gpl_usage(enum export exp, const char *m, const char *s)
 
 	switch (exp) {
 	case export_gpl:
-		fatal("modpost: GPL-incompatible module %s%s "
+		fatal("GPL-incompatible module %s%s "
 		      "uses GPL-only symbol '%s'\n", m, e, s);
 		break;
 	case export_unused_gpl:
-		fatal("modpost: GPL-incompatible module %s%s "
+		fatal("GPL-incompatible module %s%s "
 		      "uses GPL-only symbol marked UNUSED '%s'\n", m, e, s);
 		break;
 	case export_gpl_future:
-		warn("modpost: GPL-incompatible module %s%s "
+		warn("GPL-incompatible module %s%s "
 		      "uses future GPL-only symbol '%s'\n", m, e, s);
 		break;
 	case export_plain:
@@ -2179,7 +2173,7 @@ static void check_for_unused(enum export exp, const char *m, const char *s)
 	switch (exp) {
 	case export_unused:
 	case export_unused_gpl:
-		warn("modpost: module %s%s "
+		warn("module %s%s "
 		      "uses symbol '%s' marked UNUSED\n", m, e, s);
 		break;
 	default:
@@ -2198,14 +2192,11 @@ static int check_exports(struct module *mod)
 		exp = find_symbol(s->name);
 		if (!exp || exp->module == mod) {
 			if (have_vmlinux && !s->weak) {
-				if (warn_unresolved) {
+				modpost_log(warn_unresolved ? LOG_WARN : LOG_ERROR,
-					warn("\"%s\" [%s.ko] undefined!\n",
+					    "\"%s\" [%s.ko] undefined!\n",
-					     s->name, mod->name);
+					    s->name, mod->name);
-				} else {
+				if (!warn_unresolved)
-					merror("\"%s\" [%s.ko] undefined!\n",
-					       s->name, mod->name);
 					err = 1;
-				}
 			}
 			continue;
 		}
@@ -2217,8 +2208,11 @@ static int check_exports(struct module *mod)
 
 		if (exp->namespace &&
 		    !module_imports_namespace(mod, exp->namespace)) {
-			warn("module %s uses symbol %s from namespace %s, but does not import it.\n",
+			modpost_log(allow_missing_ns_imports ? LOG_WARN : LOG_ERROR,
-			     basename, exp->name, exp->namespace);
+				    "module %s uses symbol %s from namespace %s, but does not import it.\n",
+				    basename, exp->name, exp->namespace);
+			if (!allow_missing_ns_imports)
+				err = 1;
 			add_namespace(&mod->missing_namespaces, exp->namespace);
 		}
 
@@ -2565,7 +2559,7 @@ int main(int argc, char **argv)
 	struct ext_sym_list *extsym_iter;
 	struct ext_sym_list *extsym_start = NULL;
 
-	while ((opt = getopt(argc, argv, "i:e:mnsT:o:awEd:")) != -1) {
+	while ((opt = getopt(argc, argv, "i:e:mnsT:o:awENd:")) != -1) {
 		switch (opt) {
 		case 'i':
 			kernel_read = optarg;
@@ -2603,6 +2597,9 @@ int main(int argc, char **argv)
 		case 'E':
 			sec_mismatch_fatal = 1;
 			break;
+		case 'N':
+			allow_missing_ns_imports = 1;
+			break;
 		case 'd':
 			missing_namespace_deps = optarg;
 			break;
@@ -2658,7 +2655,7 @@ int main(int argc, char **argv)
 	if (dump_write)
 		write_dump(dump_write);
 	if (sec_mismatch_count && sec_mismatch_fatal)
-		fatal("modpost: Section mismatches detected.\n"
+		fatal("Section mismatches detected.\n"
 		      "Set CONFIG_SECTION_MISMATCH_WARN_ONLY=y to allow them.\n");
 	for (n = 0; n < SYMBOL_HASH_SIZE; n++) {
 		struct symbol *s;

scripts/mod/modpost.h

@@ -198,6 +198,14 @@ void *grab_file(const char *filename, unsigned long *size);
 char* get_next_line(unsigned long *pos, void *file, unsigned long size);
 void release_file(void *file, unsigned long size);
 
-void fatal(const char *fmt, ...);
+enum loglevel {
-void warn(const char *fmt, ...);
+	LOG_WARN,
-void merror(const char *fmt, ...);
+	LOG_ERROR,
+	LOG_FATAL
+};
+
+void modpost_log(enum loglevel loglevel, const char *fmt, ...);
+
+#define warn(fmt, args...)	modpost_log(LOG_WARN, fmt, ##args)
+#define merror(fmt, args...)	modpost_log(LOG_ERROR, fmt, ##args)
+#define fatal(fmt, args...)	modpost_log(LOG_FATAL, fmt, ##args)

scripts/package/mkdebian

@@ -198,6 +198,10 @@ Description: Linux support headers for userspace development
  This package provides userspaces headers from the Linux kernel.  These headers
  are used by the installed headers for GNU glibc and other system libraries.
 Multi-Arch: same
+EOF
+
+if is_enabled CONFIG_DEBUG_INFO; then
+cat <<EOF >> debian/control
 
 Package: $dbg_packagename
 Section: debug
@@ -206,6 +210,7 @@ Description: Linux kernel debugging symbols for $version
  This package will come in handy if you need to debug the kernel. It provides
  all the necessary debug symbols for the kernel and its modules.
 EOF
+fi
 
 cat <<EOF > debian/rules
 #!$(command -v $MAKE) -f