Merge tag 'kbuild-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - Improve performance in gendwarfksyms

 - Remove deprecated EXTRA_*FLAGS and KBUILD_ENABLE_EXTRA_GCC_CHECKS

 - Support CONFIG_HEADERS_INSTALL for ARCH=um

 - Use more relative paths to sources files for better reproducibility

 - Support the loong64 Debian architecture

 - Add Kbuild bash completion

 - Introduce intermediate vmlinux.unstripped for architectures that need
   static relocations to be stripped from the final vmlinux

 - Fix versioning in Debian packages for -rc releases

 - Treat missing MODULE_DESCRIPTION() as an error

 - Convert Nios2 Makefiles to use the generic rule for built-in DTB

 - Add debuginfo support to the RPM package

* tag 'kbuild-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (40 commits)
  kbuild: rpm-pkg: build a debuginfo RPM
  kconfig: merge_config: use an empty file as initfile
  nios2: migrate to the generic rule for built-in DTB
  rust: kbuild: skip `--remap-path-prefix` for `rustdoc`
  kbuild: pacman-pkg: hardcode module installation path
  kbuild: deb-pkg: don't set KBUILD_BUILD_VERSION unconditionally
  modpost: require a MODULE_DESCRIPTION()
  kbuild: make all file references relative to source root
  x86: drop unnecessary prefix map configuration
  kbuild: deb-pkg: add comment about future removal of KDEB_COMPRESS
  kbuild: Add a help message for "headers"
  kbuild: deb-pkg: remove "version" variable in mkdebian
  kbuild: deb-pkg: fix versioning for -rc releases
  Documentation/kbuild: Fix indentation in modules.rst example
  x86: Get rid of Makefile.postlink
  kbuild: Create intermediate vmlinux build with relocations preserved
  kbuild: Introduce Kconfig symbol for linking vmlinux with relocations
  kbuild: link-vmlinux.sh: Make output file name configurable
  kbuild: do not generate .tmp_vmlinux*.map when CONFIG_VMLINUX_MAP=y
  Revert "kheaders: Ignore silly-rename files"
  ...

1 files changed, 16 insertions, 7 deletions

diff --git a/Makefile b/Makefile
index d138b17b8840..e55726a71d95 100644
--- a/Makefile
+++ b/Makefile
@@ -151,9 +151,6 @@ endif
 
 export KBUILD_EXTMOD
 
-# backward compatibility
-KBUILD_EXTRA_WARN ?= $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)
-
 ifeq ("$(origin W)", "command line")
   KBUILD_EXTRA_WARN := $(W)
 endif
@@ -928,6 +925,9 @@ KBUILD_CFLAGS	+= $(CC_AUTO_VAR_INIT_ZERO_ENABLER)
 endif
 endif
 
+# Explicitly clear padding bits during variable initialization
+KBUILD_CFLAGS += $(call cc-option,-fzero-init-padding-bits=all)
+
 # 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)
@@ -1070,7 +1070,8 @@ endif
 
 # change __FILE__ to the relative path to the source directory
 ifdef building_out_of_srctree
-KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srcroot)/=)
+KBUILD_CPPFLAGS += $(call cc-option,-ffile-prefix-map=$(srcroot)/=)
+KBUILD_RUSTFLAGS += --remap-path-prefix=$(srcroot)/=
 endif
 
 # include additional Makefiles when needed
@@ -1122,6 +1123,10 @@ ifdef CONFIG_LD_ORPHAN_WARN
 LDFLAGS_vmlinux += --orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL)
 endif
 
+ifneq ($(CONFIG_ARCH_VMLINUX_NEEDS_RELOCS),)
+LDFLAGS_vmlinux	+= --emit-relocs --discard-none
+endif
+
 # Align the bit size of userspace programs with the kernel
 KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS))
 KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS))
@@ -1364,9 +1369,12 @@ 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))
+ifdef HEADER_ARCH
+	$(Q)$(MAKE) -f $(srctree)/Makefile HEADER_ARCH= SRCARCH=$(HEADER_ARCH) headers
+else
 	$(Q)$(MAKE) $(hdr-inst)=include/uapi
 	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
+endif
 
 ifdef CONFIG_HEADERS_INSTALL
 prepare: headers
@@ -1564,7 +1572,7 @@ endif # CONFIG_MODULES
 # Directories & files removed with 'make clean'
 CLEAN_FILES += vmlinux.symvers modules-only.symvers \
 	       modules.builtin modules.builtin.modinfo modules.nsdeps \
-	       modules.builtin.ranges vmlinux.o.map \
+	       modules.builtin.ranges vmlinux.o.map vmlinux.unstripped \
 	       compile_commands.json rust/test \
 	       rust-project.json .vmlinux.objs .vmlinux.export.c \
                .builtin-dtbs-list .builtin-dtb.S
@@ -1667,7 +1675,8 @@ help:
 	@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  '  headers	  - Build ready-to-install UAPI headers in usr/include'
+	@echo  '  headers_install - Install sanitised kernel UAPI headers to INSTALL_HDR_PATH'; \
 	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
 	 echo  ''
 	@echo  'Static analysers:'