Pull VDSO updates from Thomas Gleixner:

 - Consolidate the VDSO datastore further and provide support for
   mlock_all() and prefaulting.

 - Provide 32-bit legacy time related functionality only if
   CONFIG_COMPAT_32BIT_TIME is enabled. The config switch exists,
   but architecture code still exposes the legacy functionality even
   disabled.

   Clean this up by adding the missing guards and validating at build
   time that the VDSO is legacy free if disabled.

 - Consolidate the VDSO related config options in core and drivers,
   which removes some non-sensical dependencies and quite an amount of
   #ifdeffery.

 - Clean up the PAGE_SIZE definition maze

* tag 'timers-vdso-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (30 commits)
  random: vDSO: Drop custom PAGE_SIZE definitions
  LoongArch: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
  clocksource/drivers/timer-riscv: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
  clocksource/drivers/arm_arch_timer: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
  clocksource/drivers/mips-gic-timer: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
  MIPS: csrc-r4k: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
  vDSO: Make clockmode constants available without CONFIG_GENERIC_GETTIMEOFDAY
  kbuild: Support generated asm-headers in subdirectories
  vdso: Rename HAVE_GENERIC_VDSO to VDSO_DATASTORE
  vdso: Drop HAVE_GENERIC_VDSO from architecture kconfig files
  vdso: Automatically select HAVE_GENERIC_VDSO if necessary
  MIPS: vdso: Stop using CONFIG_HAVE_GENERIC_VDSO
  vdso: Remove the dependency on HAVE_GENERIC_VDSO from ARCH_HAS_VDSO_ARCH_DATA
  futex: Remove dependency on HAVE_GENERIC_VDSO from FUTEX_ROBUST_UNLOCK
  vdso/gettimeofday: Verify COMPAT_32BIT_TIME interactions
  sparc: vdso: Respect COMPAT_32BIT_TIME
  MIPS: VDSO: Respect COMPAT_32BIT_TIME
  powerpc/vdso: Respect COMPAT_32BIT_TIME
  ARM: VDSO: Respect COMPAT_32BIT_TIME
  arm64: vdso32: Respect COMPAT_32BIT_TIME
  ...

Pull timer and timekeeping core updates from Thomas Gleixner:

 - Fix a subtly inconsistency in the timekeeping code, which fails to
   account for the monotonicity adjustment in ntp_error.

   For small changes of the clocksource multiplicator (+/-1) which are
   typically used by the NTP PLL this is hard to observe. But for larger
   adjustments, e.g. caused by a direct frequency setting through
   adjtimex() the one-time uncompensated offset is significant.

   Cure this by adjusting ntp_error with the resulting offset so that
   the discrepancy is smoothed away over time

 - Make tick length calculations correct in NTP.

   The timekeeping core takes the quantisation of the clocksource into
   account when calculating the tick length to compensate for the
   deviation of the nominal NTP_INTERVAL_LENGTH.

   While timekeeping gets this right, NTP is not aware of that, which
   means it operates on the nominal value and not on the actual value
   which is determined by the clock source frequency. The rounding of a
   coarse clocksource like the ACPI PM timer results in a +127 PPM
   deviation.

   Cure this by exposing the deviation to the NTP code so that it can
   operate on the same data as the timekeeping core. This is purely
   kernel internal. User space still sees the nominal tick lenght via
   adjtimex().

 - The accuracy of the NTP adjustments is fairly approximate as the code
   assumes that the invocations are precisely in NTP interval frequency
   ticks and the final adjustment can over and under-run.

   Cure this by adjusting ntp_error by the intended skew on each tick to
   achieve the desired rate.

 - Handle the two competing skews of time offset and time adjustment
   correctly by calculating the conflict portion between the skews and
   adjusting both accordingly.

 - A set of updates and improvements for the selftests

 - The usual small fixes and improvements all over the place

* tag 'timers-core-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (58 commits)
  selftests: timers: nsleep-lat: Check all calls to clock_nanosleep() and clock_gettime()
  selftests: timers: nsleep-lat: Reuse kselftest error numbers
  selftests: timers: nsleep-lat: Explicitly list the tested clocks
  selftests: timers: nsleep-lat: Use NSEC_PER_MSEC define for unreasonable latency
  selftests: timers: nanosleep: Report each test separately
  selftests: timers: nanosleep: Explicitly handle timer_delete() failure
  selftests: timers: nanosleep: Move all single clock tests out of the loop in main()
  selftests: timers: nanosleep: Reuse kselftest error numbers
  selftests: timers: nanosleep: Explicitly list the tested clocks
  selftests: timers: nanosleep: Drop output alignment
  selftests: timers: Use clock_name() and constants from clock-helpers.h
  selftests: Add clock-helpers.h
  timer_list: Use ktime_t over nanoseconds
  timer_list: Use standard 'long long' format placeholders
  hrtimer: Add a lockdep assertion to hrtimer_update_base()
  timekeeping: Use u32 for clock_was_set_seq
  timekeeping: Rename clockid_aux_valid() to clockid_is_aux_clock()
  hrtimer: Account nr_retries on recovered interrupt retries
  timers/itimer: Zero-init old itimerval before copy to userspace
  nohz: Replace dead select with choice default
  ...

Pull treewide timer related cleanups from Thomas Gleixner:

 - Remove the leftover CLOCK_TICK_RATE which has been scheduled for
   removal more than a decade ago along with some now empty asm/timex.h
   files.

 - Consolidate delay timer calibration

   The construct of having a define in a header requires that
   architectures provided asm/timex.h for no reason. Also the function
   name for reading the delay timer is confusing at best.

   Use a config switch to enable that functionality and rename the
   function to delay_read_timer() to make the purpose clear.

   This removes some more now empty asm/timex.h files as well.

* tag 'timers-cleanups-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  calibrate: Rework delay timer calibration
  treewide: Remove CLOCK_TICK_RATE
  x86: Use PIT_TICK_RATE instead of CLOCK_TICK_RATE

Pull misc vfs updates from Christian Brauner:
 "Bigger cleanups:

   - The lockref dead-count handling is tidied up.

     The open-coded check for a count below zero as the dead marker
     relies on information the caller should not have.

   - make put_mnt_ns() leave mounts connected. Destroying a mount
     namespace disconnected its mounts from their mount points. So a
     file descriptor still open on the parent of a mount point could be
     used to peek under it.

     Locked mounts were already kept connected to prevent exactly that.
     But a mount is only locked when its tree is copied across a user
     namespace boundary. So a mount namespace set up by a privileged
     component had no locked mounts and its mounts were disconnected.
     Passing UMOUNT_CONNECTED keeps every mount connected and prevents
     that bug.

   - vfs_prepare_mode() passes S_IFDIR for directories. I meant to fix
     that ago but didn't get to it. So now someone finally did it.

     This kills the exception where the mode could be 0 when a directory
     was created whereas every other creation operation passed it
     explicitly already.

   - move long delayed work for ufs, jffs2, hfsplus, hfs and affs from
     the per-cpu system_long_wq to the new unbound system_dfl_long_wq.

     None of that work relies on per-cpu state and the work item is
     enqueued with queue_delayed_work() whose timer is global anyway. So
     it may as well benefit from scheduler task placement.

  Smaller fixes and cleanups:

   - unlock_buffer() and journal_end_buffer_io_sync() use
     clear_and_wake_up_bit()

   - the pipe page pools are unified into a single per-pipe pool and the
     extra wake_up(rd_wait) is limited to EPOLLET consumers

   - eventpoll now computes its timer slack lazily in ep_poll()

   - shrink_dcache_for_umount() keeps making progress on busy roots

   - excess xarray nodes are freed in clear_inode()

   - romfs detects hard link cycles

   - the user path of nested backing files is fixed

   - pidfd holds exec_update_lock around the namespace ioctl

   - non-memcg-aware nr_cached_objects is skipped during memcg slab
     shrink

   - iomap_write_iter() always returns status

   - mangle_path() is renamed to seq_mangle_path()

   - inode timestamp accessors are annotated

   - new regression test for pipe->poll_usage.

   - a few documentation, kernel-doc and selftest fixes"

* tag 'vfs-7.3-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (67 commits)
  selftests/namespaces: Fix racy pipe handshake in timens and pidns_separate
  selftests/epoll: add a regression test for pipe->poll_usage
  pipe: only enable the extra wake_up(rd_wait) for EPOLLET consumers
  pidfd: hold exec_update_lock around namespace ioctl
  fs: fix user path of nested backing files
  fs: remove stale inode_insert5() kernel-doc parameter
  fs: fix switch/case indentation in sysfs() syscall
  fs: document semantics of kstat::{uid,gid} fields
  dcache: keep shrink_dcache_for_umount() making progress on busy roots
  seq_file: rename mangle_path to seq_mangle_path
  nstree: add/fix struct ns_id_req kernel-doc member fields
  dcache: use lockref routines for dead count checks
  lockref: tidy up dead count handling
  initramfs: fix typo in reserve_initrd_mem comment
  fs/pipe: unify the page pools into a single per-pipe pool
  fs: annotate inode timestamp accessors
  eventpoll: compute timer slack lazily in ep_poll()
  selftests/filesystems: add mntns cleanup test
  put_mnt_ns(): leave mounts connected
  affs: Move long delayed work on system_dfl_long_wq
  ...

Pull kthread vfs updates from Christian Brauner:
 "This stops kernel threads from sharing filesystem state with
  userspace. This work is about 3 cycles old and has been in -next
  for about that time.

  When the kernel boots init_task creates PID 1 and then kthreadd. From
  that point every kthread and PID 1 share the same fs_struct. That is
  why pivot_root() has to rewrite the fs_struct of all kthreads. The
  rewriting exists so that kthreads can use init's filesystem state when
  they want to. It also means userspace can move the ground out from
  under the kernel.

  PID 1 now gets a completely separate fs_struct. All kthreads are
  anchored in a private SB_KERNMOUNT instance of nullfs that cannot be
  mounted on and cannot be used to follow other mounts. Userspace init
  can no longer affect kthread filesystem state and kthreads can no
  longer affect userspace fs state without explicit opting in to that.

  Path lookup from a kthread now fails by default. It makes it
  deliberately hard to offload security sensitive operations into init's
  filesystem state from a kthread.

  Places that legitimately need to look something up there opt in
  through the new scoped_with_init_fs() which temporarily overrides the
  caller's fs_struct with init's. usermodehelpers remain the only kernel
  tasks that genuinely share init's filesystem state, since they execute
  random binaries in the root filesystem (excellent...).

  The visible result is that /proc/2/root is a nullfs with an empty
  mountinfo while /proc/1/root is the real root"

* tag 'vfs-7.3-rc1.kthread' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (26 commits)
  initramfs_test: use test init/exit hooks to override init fs
  fs: stop rewriting paths for PF_EXITING | PF_DUMPCORE
  fs: stop rewriting kthread fs structs
  fs: start all kthreads in nullfs
  nullfs: make nullfs multi-instance
  devtmpfs: create private mount namespace
  fs: add umh argument to struct kernel_clone_args
  fs: stop sharing fs_struct between init_task and pid 1
  af_unix: use scoped_with_init_fs() for coredump socket lookup
  initramfs: use scoped_with_init_fs() for rootfs unpacking
  pnfs/blocklayout: use scoped_with_init_fs() for SCSI device lookup
  ksmbd: use scoped_with_init_fs() for VFS path operations
  ksmbd: use scoped_with_init_fs() for filesystem info path lookup
  ksmbd: use scoped_with_init_fs() for share path resolution
  fs: use scoped_with_init_fs() for kernel_read_file_from_path_initns()
  coredump: use scoped_with_init_fs() for coredump path resolution
  btrfs: use scoped_with_init_fs() for update_dev_time()
  scsi: target: use scoped_with_init_fs() for APTPL metadata
  scsi: target: use scoped_with_init_fs() for ALUA metadata
  crypto: ccp: use scoped_with_init_fs() for SEV file access
  ...

'select' does not work on config options in a 'choice', so currently the
'select VIRT_CPU_ACCOUNTING_GEN' for NO_HZ_FULL is dead, with the choice
option VIRT_CPU_ACCOUNTING_GEN only being enabled when NO_HZ_FULL=y because
the other choice members depend on NO_HZ_FULL=n.

Remove the dead select, and encode this relationship as a default of the
choice, instead.

This dead select was found by kconfirm, a static analysis tool for Kconfig.

Signed-off-by: Julian Braha <julianbraha@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Reviewed-by: Bradley Morgan <include@grrlz.net>
Reviewed-by: Nicolas Schier <nsc@kernel.org>
Link: https://patch.msgid.link/20260801160140.2391000-1-julianbraha@gmail.com

Most initramfs kunit tests interact with initramfs via
unpack_to_rootfs() and subsequently init_stat(), init_unlink(), etc.

It's cleaner and less error-prone to override current->fs with
userspace_init_fs for all initramfs_test_suite tests.

Link: https://patch.msgid.link/20260701-work-kunit-nullfs-v1-1-dfa60270434f@kernel.org [1]
Link: https://patch.msgid.link/20260729151320.21001-2-ddiss@suse.de # folded into [1]
Fixes: 32750c77e811 ("fs: start all kthreads in nullfs")
Reported-by: Mark Brown <broonie@kernel.org>
Closes: https://lore.kernel.org/r/akOrbOsKUqgZarGw@sirena.org.uk
Signed-off-by: David Disseldorp <ddiss@suse.de>
Co-developed-by: David Disseldorp <ddiss@suse.de>
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>

Fix a minor typo in the comment inside reserve_initrd_mem.
Change "virtul" to "virtual".

Signed-off-by: Shivank Sharma <shivanksharma2376543@gmail.com>
Link: https://patch.msgid.link/20260716160944.1331096-1-shivanksharma2376543@gmail.com
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>

The header define in asm/timex,h and the naming of the function to read the
delay timer are confusing at best.

Convert it to a config switch selected by the archictures which provide the
functionality and rename the function to delay_read_timer(), which makes
the purpose clear. Move the declaration to linux/delay.h where it belongs.

Remove the resulting empty asm/timex.h files as well.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260410120317.978403520@kernel.org

The robust futex unlock functionality has no relation to the generic
vDSO functionality.

Remove the dependency.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://patch.msgid.link/20260709-vdso-have_generic_vdso-v1-1-d2e1061f268b@linutronix.de