Pull VDSO updates from Thomas Gleixner:
 "Updates for the VDSO subsystem:

   - Ensure that the CLOCK_AUX base calculations are properly scaled
     against the base timekeeper. The update function failed to take the
     fractional nanosecond part into account, which results in a
     rounding error.

   - Cleanup and consolidate the vsyscall headers to get rid of
     pointless copies all over the architectures.

   - Replace a runtime conditional in the time getter function for
     namespaced clocks by simple pointer arithmetic which speeds up the
     read function"

* tag 'timers-vdso-2026-10-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  vdso/vsyscall: Keep the CLOCK_AUX base scaled
  vdso/math64: Add and use __iter_div64_u64_rem()
  vdso/math64: Use OPTIMIZER_HIDE_VAR() in __iter_div_u64_rem()
  vdso/gettimeofday: Avoid runtime conditional in do_hres_timens()
  vdso: Remove __ASSEMBLER__ guards from vsyscall.h
  vdso: Add asm-generic/vdso/vsyscall.h
  vdso: Remove unnecessary vdso/vsyscall.h includes
  riscv/hwprobe: Include vdso/datapage.h
  arm64/vdso: Delete asm/vdso/vsyscall.h inclusions
  x86/vdso: Delete asm/vdso/vsyscall.h inclusions
  sparc/vdso: Delete asm/vdso/vsyscall.h inclusion
  s390/vdso: Delete asm/vdso/vsyscall.h inclusions
  sparc/vdso: Move __VDSO_PAGES to asm/vdso.h
  x86/vdso: Move vDSO page definitions to asm/vdso.h
  vdso: Delete asm-generic/vdso/vsyscall.h
  vdso/vsyscall: Define fallback time synchronization functions in vsyscall.c
  vdso/getrandom: Define fallback __arch_get_vdso_u_rng_data() in getrandom.c
  vdso/gettimeofday: Define fallback __arch_get_vdso_u_time_data() in gettimeofday.c
  vdso: Move the kernel-side time update helpers to a new header

Pull Kbuild / Kconfig updates from Nathan Chancellor:
 "Kbuild:

   - Suppress compiler flags in debug info for external module builds

   - Use '-fmacro-prefix-map' in more places in the build

   - Merge initial set of changes from Lorenzo's speed up series, along
     with some fixes found through testing:

     - Avoid allocating .modinfo in vmlinux

     - Speed up kallsyms by indexing symbols by token and outputting
       binary data to disk directly then including in assembly via
       .incbin

     - Don't sort $(NM) output when unnecessary

     - Only emit relocations on the final vmlinx link

     - Reimplement mksysmap in C

     - Move many cc-option and ld-option calls into the Kconfig stage to
       cache their results

     - Use pigz for gzip compression when available

   - Move gen_init_cpio and gen_initramfs.sh from usr/ to scripts/

   - Add a TOML configuration to scripts/container and update
     documentation accordingly

   - Add a generic, opt-in mechanism for checking that headers can
     compile standalone

   - Update machine function splitting argument for LLVM 24 rename in
     AutoFDO build

   - Miscellaneous minor clean ups, fixes, and hardening, mostly
     found/fixed via LLMs

  Kconfig:

   - Turn recursive ranges into an error

   - Fix savedefconfig for defaults that were adjusted for being out of
     range and revert a previously applied workaround

   - Improvements and hardening around integer and hexadecimal values

   - Emit a warning when selecting or implying a choice symbol, which
     has no effect

   - Emit a warning when KCONFIG_PROBABILITY is malformed

   - Introduce def_string / def_int / def_hex to mirror the existing
     def_bool / def_tristate to succinctly set a value and type at the
     same time.

   - Add cc-option-str and ld-option-str macros to act like Kbuild's
     cc-option and ld-option, returning the string when the option is
     supported, allowing many checks to be moved into Kconfig

   - Minor usability improvements to Kconfig tests"

* tag 'kbuild-7.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux: (59 commits)
  kbuild: AutoFDO: Update split machine function argument for upstream rename
  kbuild: Mark the initcall ordering recipe as recursive
  kbuild: Mark the gzip recipes as recursive
  localmodconfig: Explicitly report boolean configs during integrity check
  scripts/make_fit: Ignore schema checks when decomposing DTBs
  clang-tools: Import os for broken pipe handling
  kconfig: use the value argument in sym_get_near_range_bound()
  kconfig: fix infinite loop in conf_choice() when no choice value is visible
  kconfig: cleanup stale comment about 'keys' array
  kconfig: Improve ergonomics around disabling warnings with cc-option
  scripts/Kconfig.toolchain: Drop compiler symbols from dependencies
  checkkconfigsymbols.py: Parse Git status output line by line
  gen_init_cpio: stop parsing on lines with a missing argument list
  .gitignore: drop Module.markers
  .gitignore: ignore pacman package signatures
  kbuild: add header check facility as a manually run static analyzer
  Documentation: dev-tools: refer to user ID rather than id
  Documentation: dev-tools: update container.rst with config file
  scripts: add TOML config to container tool
  kconfig: tests: {old,save}defconfig: Forward dynamic keyword arguments
  ...

Most architectures' asm/vdso/vsyscall.h do not define any symbols.

Add an empty asm-generic variant and replace the pointless
architecture-specific copies.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260909-vdso-asm-generic-vsyscall-h-v1-14-63ae856cc659@linutronix.de

Recent refactoring have made the header empty.

Remove it and its mentions.

Also that header was never a real asm-generic header anyways.
It had no reason to be in the asm-generic directory.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260909-vdso-asm-generic-vsyscall-h-v1-5-63ae856cc659@linutronix.de

__arch_update_vdso_clock() and __arch_sync_vdso_time_data() are only
used in vsyscall.c. vsyscall.h has become a dumping ground for different
kinds of fallbacks.

Move the fallback function definitions into vsyscall.c.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260909-vdso-asm-generic-vsyscall-h-v1-4-63ae856cc659@linutronix.de

__arch_get_vdso_u_rng_data() is only used in getrandom.c. vsyscall.h
has become a dumping ground for different kinds of fallbacks.

Move the fallback function definition into getrandom.c,
similar to other fallbacks.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260909-vdso-asm-generic-vsyscall-h-v1-3-63ae856cc659@linutronix.de

__arch_get_vdso_u_time_data() is only used in gettimeofday.c. vsyscall.h
has become a dumping ground for different kinds of fallbacks.

Move the fallback function definition into gettimeofday.c,
similar to other fallbacks.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260909-vdso-asm-generic-vsyscall-h-v1-2-63ae856cc659@linutronix.de

Builds with CONFIG_LD_DEAD_CODE_DATA_ELIMINATION=y, such as arm
allmodconfig, now fail while extracting modules.builtin.modinfo:

  arm-linux-gnueabihf-objcopy: vmlinux.unstripped: can't dump section
  '.modinfo' - it does not exist: file format not recognized
  /bin/sh: 1: cannot open modules.builtin.modinfo: No such file

or, with LLVM:

  llvm-objcopy: error: 'vmlinux.unstripped': section '.modinfo' not
  found

Nothing references the MODULE_INFO() strings, so --gc-sections
discards every .modinfo input section and vmlinux.unstripped ends up
with no .modinfo data. This is not new: ever since
modules.builtin.modinfo started being extracted from
vmlinux.unstripped, these builds have silently produced an empty
file, losing the modinfo of every built-in module. An arm
multi_v7_defconfig build with LD_DEAD_CODE_DATA_ELIMINATION on current
mainline yields a 0 byte modules.builtin.modinfo. The switch to
--dump-section only turned that into a build error.

Wrap the input section in KEEP() so that the linker retains it. The
output section is still (INFO), so nothing is allocated for it. With
the same arm config, modules.builtin.modinfo now has 14119 entries,
and on x86_64 defconfig, where nothing is garbage collected, it is
byte-identical before and after this change.

Found by KernelCI builds of the linus-next tree.

Fixes: 39cfd5b12160 ("kbuild: extract modules.builtin.modinfo from vmlinux.unstripped")
Fixes: 5fe4dd596641 ("kbuild: do not allocate .modinfo in vmlinux")
Assisted-by: LLM
Signed-off-by: Sasha Levin <sashal@kernel.org>
Link: https://patch.msgid.link/20260927161227.1179863-1-sashal@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>

Commit 3e86e4d74c04 ("kbuild: keep .modinfo section in vmlinux.unstripped")
placed MODULE_INFO() strings in the .modinfo section in vmlinux.unstripped,
however it left the section allocatable, so it gets assigned an address and
on arm64, arm and riscv, the section is tagged as PT_LOAD.

This is useless as the data is ultimately stripped anyway.

Doing this results in a lot of unnecessary work - each pass copies the
whole file, 450 MiB with relocations for an x86 allmodconfig build and 250
MiB for an arm64 allmodconfig build.

This adds ~0.7s on the serial tail of every build for arm64 and ~0.2s for
x86 (the tail is single-threaded work done after parallel work has
finished).

Nothing requires .modinfo to exist at an address, so mark the output
section (INFO) so that it's not allocated and use --dump-section to extract
it as -O only emits allocated sections.

The dump doesn't pick up the arch's OBJCOPYFLAGS any longer as they should
not impact the output of this section.

Image, bzImage, System.map and modules.builtin.modinfo are unchanged and
the stripped vmlinux differs only in its program headers.

The objcopy passes are on the serial tail of every build that links
vmlinux, no-op builds are unchanged.

Whole build, 128-thread Threadripper 9980X, best of N runs:

                                         before   after     delta
                                         -------------------------------
  x86 defconfig, touch mm/vma.c, gcc       11.2s    11.1s    -0.15s (-1%)
  x86 defconfig, touch mm/vma.c, clang     11.3s    11.1s    -0.19s (-2%)
  x86 defconfig, clean, gcc                32.5s    32.3s    -0.16s (-1%)
  x86 defconfig, clean, clang              34.5s    34.2s    -0.26s (-1%)
  x86 allmodconfig, touch mm/vma.c, gcc    40.1s    39.7s    -0.44s (-1%)

Assisted-by: LLM
Reviewed-by: Kees Cook <kees@kernel.org>
Signed-off-by: Lorenzo Stoakes (ARM) <ljs@kernel.org>
Reviewed-by: Nicolas Schier <n.schier@fritz.com>
Link: https://patch.msgid.link/20260923-build-speedup-v4-1-73128809a4a4@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>

Commit d50f21091358 ("kbuild: align modinfo section for Secureboot
Authenticode EDK2 compat") aligned .modinfo because it appeared in the
x86_64 compressed kernel image after commit 3e86e4d74c04 ("kbuild: keep
.modinfo section in vmlinux.unstripped"), breaking boot.

Commit 8678591b4746 ("kbuild: Split .modinfo out from ELF_DETAILS")
properly addresses .modinfo appearing in unexpected contexts like
compressed images by moving it out of ELF_DETAILS and explicitly
specifying its location in every architecture's vmlinux linker script or
discarding it where it may appear elsewhere.

Effectively revert commit d50f21091358 ("kbuild: align modinfo section
for Secureboot Authenticode EDK2 compat") and its follow up fix,
commit a26a6c93edfe ("kbuild: Strip trailing padding bytes from
modules.builtin.modinfo"), as they are no longer necessary in the
current tree. This simplifies future cleanups.

Reviewed-by: Nicolas Schier <n.schier@fritz.com>
Link: https://patch.msgid.link/20260918005142.GA1585590@ax162/
Signed-off-by: Nathan Chancellor <nathan@kernel.org>