Pull Kbuild updates from Masahiro Yamada:

 - Remove the deprecated rule to build *.dtbo from *.dts

 - Refactor section mismatch detection in modpost

 - Fix bogus ARM section mismatch detections

 - Fix error of 'make gtags' with O= option

 - Add Clang's target triple to KBUILD_CPPFLAGS to fix a build error
   with the latest LLVM version

 - Rebuild the built-in initrd when KBUILD_BUILD_TIMESTAMP is changed

 - Ignore more compiler-generated symbols for kallsyms

 - Fix 'make local*config' to handle the ${CONFIG_FOO} form in Makefiles

 - Enable more kernel-doc warnings with W=2

 - Refactor <linux/export.h> by generating KSYMTAB data by modpost

 - Deprecate <asm/export.h> and <asm-generic/export.h>

 - Remove the EXPORT_DATA_SYMBOL macro

 - Move the check for static EXPORT_SYMBOL back to modpost, which makes
   the build faster

 - Re-implement CONFIG_TRIM_UNUSED_KSYMS with one-pass algorithm

 - Warn missing MODULE_DESCRIPTION when building modules with W=1

 - Make 'make clean' robust against too long argument error

 - Exclude more objects from GCOV to fix CFI failures with GCOV

 - Allow 'make modules_install' to install modules.builtin and
   modules.builtin.modinfo even when CONFIG_MODULES is disabled

 - Include modules.builtin and modules.builtin.modinfo in the
   linux-image Debian package even when CONFIG_MODULES is disabled

 - Revive "Entering directory" logging for the latest Make version

* tag 'kbuild-v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (72 commits)
  modpost: define more R_ARM_* for old distributions
  kbuild: revive "Entering directory" for Make >= 4.4.1
  kbuild: set correct abs_srctree and abs_objtree for package builds
  scripts/mksysmap: Ignore prefixed KCFI symbols
  kbuild: deb-pkg: remove the CONFIG_MODULES check in buildeb
  kbuild: builddeb: always make modules_install, to install modules.builtin*
  modpost: continue even with unknown relocation type
  modpost: factor out Elf_Sym pointer calculation to section_rel()
  modpost: factor out inst location calculation to section_rel()
  kbuild: Disable GCOV for *.mod.o
  kbuild: Fix CFI failures with GCOV
  kbuild: make clean rule robust against too long argument error
  script: modpost: emit a warning when the description is missing
  kbuild: make modules_install copy modules.builtin(.modinfo)
  linux/export.h: rename 'sec' argument to 'license'
  modpost: show offset from symbol for section mismatch warnings
  modpost: merge two similar section mismatch warnings
  kbuild: implement CONFIG_TRIM_UNUSED_KSYMS without recursion
  modpost: use null string instead of NULL pointer for default namespace
  modpost: squash sym_update_namespace() into sym_add_exported()
  ...

Add --orphan-handlin for vdsos, and adjust vdso linker scripts to deal
with orphan sections.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230609051002.3342-1-npiggin@gmail.com

A future change will move CLANG_FLAGS from KBUILD_{A,C}FLAGS to
KBUILD_CPPFLAGS so that '--target' is available while preprocessing.
When that occurs, the following error appears when building the compat
PowerPC vDSO:

  clang: error: unsupported option '-mbig-endian' for target 'x86_64-pc-linux-gnu'
  make[3]: *** [.../arch/powerpc/kernel/vdso/Makefile:76: arch/powerpc/kernel/vdso/vdso32.so.dbg] Error 1

Explicitly add CLANG_FLAGS to ldflags-y, so that '--target' will always
be present.

Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

The actual intention is that no dynamic relocation exists in the VDSO. For
this the VDSO build validates that the resulting .so file does not have any
relocations which are specified via $(ARCH_REL_TYPE_ABS) per architecture,
which is fragile as e.g. ARM64 lacks an entry for R_AARCH64_RELATIVE. Aside
of that ARCH_REL_TYPE_ABS is a misnomer as it checks for relative
relocations too.

However, some GNU ld ports produce unneeded R_*_NONE relocation entries. If
a port fails to determine the exact .rel[a].dyn size, the trailing zeros
become R_*_NONE relocations. E.g. ld's powerpc port recently fixed
https://sourceware.org/bugzilla/show_bug.cgi?id=29540). R_*_NONE are
generally a no-op in the dynamic loaders. So just ignore them.

Remove the ARCH_REL_TYPE_ABS defines and just validate that the resulting
.so file does not contain any R_* relocation entries except R_*_NONE.

Signed-off-by: Fangrui Song <maskray@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com> # for aarch64
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> # for vDSO, aarch64
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Link: https://lore.kernel.org/r/20230310190750.3323802-1-maskray@google.com

Pull Kbuild updates from Masahiro Yamada:

 - Change V=1 option to print both short log and full command log

 - Allow V=1 and V=2 to be combined as V=12

 - Make W=1 detect wrong .gitignore files

 - Tree-wide cleanups for unused command line arguments passed to Clang

 - Stop using -Qunused-arguments with Clang

 - Make scripts/setlocalversion handle only correct release tags instead
   of any arbitrary annotated tag

 - Create Debian and RPM source packages without cleaning the source
   tree

 - Various cleanups for packaging

* tag 'kbuild-v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (74 commits)
  kbuild: rpm-pkg: remove unneeded KERNELRELEASE from modules/headers_install
  docs: kbuild: remove description of KBUILD_LDS_MODULE
  .gitattributes: use 'dts' diff driver for *.dtso files
  kbuild: deb-pkg: improve the usability of source package
  kbuild: deb-pkg: fix binary-arch and clean in debian/rules
  kbuild: tar-pkg: use tar rules in scripts/Makefile.package
  kbuild: make perf-tar*-src-pkg work without relying on git
  kbuild: deb-pkg: switch over to source format 3.0 (quilt)
  kbuild: deb-pkg: make .orig tarball a hard link if possible
  kbuild: deb-pkg: hide KDEB_SOURCENAME from Makefile
  kbuild: srcrpm-pkg: create source package without cleaning
  kbuild: rpm-pkg: build binary packages from source rpm
  kbuild: deb-pkg: create source package without cleaning
  kbuild: add a tool to list files ignored by git
  Documentation/llvm: add Chimera Linux, Google and Meta datacenters
  setlocalversion: use only the correct release tag for git-describe
  setlocalversion: clean up the construction of version output
  .gitignore: ignore *.cover and *.mbx
  kbuild: remove --include-dir MAKEFLAG from top Makefile
  kbuild: fix trivial typo in comment
  ...

Exclude various incompatible compilation units from KCSAN
instrumentation.

Signed-off-by: Rohan McLure <rmclure@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230206021801.105268-2-rmclure@linux.ibm.com

After commit 8d9acfce3332 ("kbuild: Stop using '-Qunused-arguments' with
clang"), the PowerPC vDSO shows the following error with clang-13 and
older when CONFIG_INIT_STACK_ALL_ZERO is enabled:

  clang: error: argument unused during compilation: '-enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang' [-Werror,-Wunused-command-line-argument]

clang-14 added a change to make sure this flag never triggers
-Wunused-command-line-argument, so it is fixed with newer releases. For
older releases that the kernel still supports building with, just filter
out this flag, as has been done for other flags.

Fixes: f0a42fbab447 ("powerpc/vdso: Improve linker flags")
Fixes: 8d9acfce3332 ("kbuild: Stop using '-Qunused-arguments' with clang")
Link: https://github.com/llvm/llvm-project/commit/ca6d5813d17598cd180995fb3bdfca00f364475f
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

When clang's -Qunused-arguments is dropped from KBUILD_CPPFLAGS, it
warns:

  clang-16: error: argument unused during compilation: '-fno-stack-clash-protection' [-Werror,-Wunused-command-line-argument]

This warning happens because vgettimeofday-32.c gets its base CFLAGS
from the main kernel, which may contain flags that are only supported on
a 64-bit target but not a 32-bit one, which is the case here.
-fstack-clash-protection and its negation are only suppported by the
64-bit powerpc target but that flag is included in an invocation for a
32-bit powerpc target, so clang points out that while the flag is one
that it recognizes, it is not actually used by this compiler job.

To eliminate the warning, remove -fno-stack-clash-protection from
vgettimeofday-32.c's CFLAGS when using clang, as has been done for other
flags previously.

Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Linux Kernel Functional Testing <lkft@linaro.org>
Tested-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

When clang's -Qunused-arguments is dropped from KBUILD_CPPFLAGS, there
are several warnings in the PowerPC vDSO:

  clang-16: error: -Wl,-soname=linux-vdso32.so.1: 'linker' input unused [-Werror,-Wunused-command-line-argument]
  clang-16: error: -Wl,--hash-style=both: 'linker' input unused [-Werror,-Wunused-command-line-argument]
  clang-16: error: argument unused during compilation: '-shared' [-Werror,-Wunused-command-line-argument]

  clang-16: error: argument unused during compilation: '-nostdinc' [-Werror,-Wunused-command-line-argument]
  clang-16: error: argument unused during compilation: '-Wa,-maltivec' [-Werror,-Wunused-command-line-argument]

The first group of warnings point out that linker flags were being added
to all invocations of $(CC), even though they will only be used during
the final vDSO link. Move those flags to ldflags-y.

The second group of warnings are compiler or assembler flags that will
be unused during linking. Filter them out from KBUILD_CFLAGS so that
they are not used during linking.

Additionally, '-z noexecstack' was added directly to the ld_and_check
rule in commit 1d53c0192b15 ("powerpc/vdso: link with -z noexecstack")
but now that there is a common ldflags variable, it can be moved there.

Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Linux Kernel Functional Testing <lkft@linaro.org>
Tested-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

When clang's -Qunused-arguments is dropped from KBUILD_CPPFLAGS, it
warns:

  clang-16: error: argument unused during compilation: '-s' [-Werror,-Wunused-command-line-argument]

The compiler's '-s' flag is a linking option (it is passed along to the
linker directly), which means it does nothing when the linker is not
invoked by the compiler. The kernel builds all .o files with '-c', which
stops the compilation pipeline before linking, so '-s' can be safely
dropped from ASFLAGS.

Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Segher Boessenkool <segher@kernel.crashing.org>
Tested-by: Linux Kernel Functional Testing <lkft@linaro.org>
Tested-by: Anders Roxell <anders.roxell@linaro.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>