Pull Rust fix from Miguel Ojeda:

  - 'hrtimer': fix future compile error when the 'impl_has_hr_timer!'
    macro starts to get called

* tag 'rust-fixes-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux:
  rust: time: Fix compile error in impl_has_hr_timer macro

Introduce `CpuId::current()`, a constructor that wraps the C function
`raw_smp_processor_id()` to retrieve the current CPU identifier without
guaranteeing stability.

This function should be used only when the caller can ensure that
the CPU ID won't change unexpectedly due to preemption or migration.

Suggested-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>

Use the newly defined `CpuId` abstraction instead of raw CPU numbers.

This also fixes a doctest failure for configurations where `nr_cpu_ids <
4`.

The C `cpumask_{set|clear}_cpu()` APIs emit a warning when given an
invalid CPU number — but only if `CONFIG_DEBUG_PER_CPU_MAPS=y` is set.

Meanwhile, `cpumask_weight()` only considers CPUs up to `nr_cpu_ids`,
which can cause inconsistencies: a CPU number greater than `nr_cpu_ids`
may be set in the mask, yet the weight calculation won't reflect it.

This leads to doctest failures when `nr_cpu_ids < 4`, as the test tries
to set CPUs 2 and 3:

  rust_doctest_kernel_cpumask_rs_0.location: rust/kernel/cpumask.rs:180
  rust_doctest_kernel_cpumask_rs_0: ASSERTION FAILED at rust/kernel/cpumask.rs:190

Fixes: 8961b8cb3099 ("rust: cpumask: Add initial abstractions")
Reported-by: Miguel Ojeda <ojeda@kernel.org>
Closes: https://lore.kernel.org/rust-for-linux/CANiq72k3ozKkLMinTLQwvkyg9K=BeRxs1oYZSKhJHY-veEyZdg@mail.gmail.com/
Reported-by: Andreas Hindborg <a.hindborg@kernel.org>
Closes: https://lore.kernel.org/all/87qzzy3ric.fsf@kernel.org/
Suggested-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>

This adds abstraction for representing a CPU identifier.

Suggested-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>

Fix a compile error in the `impl_has_hr_timer!` macro as follows:

error[E0599]: no method named cast_mut found for raw pointer *mut Foo in the current scope

The `container_of!` macro already returns a mutable pointer when used
in a `*mut T` context so the `.cast_mut()` method is not available.

[ We missed this one because there is no caller yet and it is
  a macro. - Miguel ]

Fixes: 74d6a606c2b3 ("rust: retain pointer mut-ness in `container_of!`")
Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Reviewed-by: Benno Lossin <lossin@kernel.org>
Acked-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20250606020505.3186533-1-fujita.tomonori@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Replace `/// SAFETY` comments in doc comments with proper `# Safety`
sections, as per rustdoc conventions.

Also mark the C FFI callbacks as `unsafe` to correctly reflect their
safety requirements.

Reported-by: Miguel Ojeda <ojeda@kernel.org>
Closes: https://github.com/Rust-for-Linux/linux/issues/1169
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

Pull char / misc / iio driver updates from Greg KH:
 "Here is the big char/misc/iio and other small driver subsystem pull
  request for 6.16-rc1.

  Overall, a lot of individual changes, but nothing major, just the
  normal constant forward progress of new device support and cleanups to
  existing subsystems. Highlights in here are:

   - Large IIO driver updates and additions and device tree changes

   - Android binder bugfixes and logfile fixes

   - mhi driver updates

   - comedi driver updates

   - counter driver updates and additions

   - coresight driver updates and additions

   - echo driver removal as there are no in-kernel users of it

   - nvmem driver updates

   - spmi driver updates

   - new amd-sbi driver "subsystem" and drivers added

   - rust miscdriver binding documentation fix

   - other small driver fixes and updates (uio, w1, acrn, hpet,
     xillybus, cardreader drivers, fastrpc and others)

  All of these have been in linux-next for quite a while with no
  reported problems"

* tag 'char-misc-6.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (390 commits)
  binder: fix yet another UAF in binder_devices
  counter: microchip-tcb-capture: Add watch validation support
  dt-bindings: iio: adc: Add ROHM BD79100G
  iio: adc: add support for Nuvoton NCT7201
  dt-bindings: iio: adc: add NCT7201 ADCs
  iio: chemical: Add driver for SEN0322
  dt-bindings: trivial-devices: Document SEN0322
  iio: adc: ad7768-1: reorganize driver headers
  iio: bmp280: zero-init buffer
  iio: ssp_sensors: optimalize -> optimize
  HID: sensor-hub: Fix typo and improve documentation
  iio: admv1013: replace redundant ternary operator with just len
  iio: chemical: mhz19b: Fix error code in probe()
  iio: adc: at91-sama5d2: use IIO_DECLARE_BUFFER_WITH_TS
  iio: accel: sca3300: use IIO_DECLARE_BUFFER_WITH_TS
  iio: adc: ad7380: use IIO_DECLARE_DMA_BUFFER_WITH_TS
  iio: adc: ad4695: rename AD4695_MAX_VIN_CHANNELS
  iio: adc: ad4695: use IIO_DECLARE_DMA_BUFFER_WITH_TS
  iio: introduce IIO_DECLARE_BUFFER_WITH_TS macros
  iio: make IIO_DMA_MINALIGN minimum of 8 bytes
  ...

Pull Rust updates from Miguel Ojeda:
 "Toolchain and infrastructure:

   - KUnit '#[test]'s:

      - Support KUnit-mapped 'assert!' macros.

        The support that landed last cycle was very basic, and the
        'assert!' macros panicked since they were the standard library
        ones. Now, they are mapped to the KUnit ones in a similar way to
        how is done for doctests, reusing the infrastructure there.

        With this, a failing test like:

            #[test]
            fn my_first_test() {
                assert_eq!(42, 43);
            }

        will report:

            # my_first_test: ASSERTION FAILED at rust/kernel/lib.rs:251
            Expected 42 == 43 to be true, but is false
            # my_first_test.speed: normal
            not ok 1 my_first_test

      - Support tests with checked 'Result' return types.

        The return value of test functions that return a 'Result' will
        be checked, thus one can now easily catch errors when e.g. using
        the '?' operator in tests.

        With this, a failing test like:

            #[test]
            fn my_test() -> Result {
                f()?;
                Ok(())
            }

        will report:

            # my_test: ASSERTION FAILED at rust/kernel/lib.rs:321
            Expected is_test_result_ok(my_test()) to be true, but is false
            # my_test.speed: normal
            not ok 1 my_test

      - Add 'kunit_tests' to the prelude.

   - Clarify the remaining language unstable features in use.

   - Compile 'core' with edition 2024 for Rust >= 1.87.

   - Workaround 'bindgen' issue with forward references to 'enum' types.

   - objtool: relax slice condition to cover more 'noreturn' functions.

   - Use absolute paths in macros referencing 'core' and 'kernel'
     crates.

   - Skip '-mno-fdpic' flag for bindgen in GCC 32-bit arm builds.

   - Clean some 'doc_markdown' lint hits -- we may enable it later on.

  'kernel' crate:

   - 'alloc' module:

      - 'Box': support for type coercion, e.g. 'Box<T>' to 'Box<dyn U>'
        if 'T' implements 'U'.

      - 'Vec': implement new methods (prerequisites for nova-core and
        binder): 'truncate', 'resize', 'clear', 'pop',
        'push_within_capacity' (with new error type 'PushError'),
        'drain_all', 'retain', 'remove' (with new error type
        'RemoveError'), insert_within_capacity' (with new error type
        'InsertError').

        In addition, simplify 'push' using 'spare_capacity_mut', split
        'set_len' into 'inc_len' and 'dec_len', add type invariant 'len
        <= capacity' and simplify 'truncate' using 'dec_len'.

   - 'time' module:

      - Morph the Rust hrtimer subsystem into the Rust timekeeping
        subsystem, covering delay, sleep, timekeeping, timers. This new
        subsystem has all the relevant timekeeping C maintainers listed
        in the entry.

      - Replace 'Ktime' with 'Delta' and 'Instant' types to represent a
        duration of time and a point in time.

      - Temporarily add 'Ktime' to 'hrtimer' module to allow 'hrtimer'
        to delay converting to 'Instant' and 'Delta'.

   - 'xarray' module:

      - Add a Rust abstraction for the 'xarray' data structure. This
        abstraction allows Rust code to leverage the 'xarray' to store
        types that implement 'ForeignOwnable'. This support is a
        dependency for memory backing feature of the Rust null block
        driver, which is waiting to be merged.

      - Set up an entry in 'MAINTAINERS' for the XArray Rust support.
        Patches will go to the new Rust XArray tree and then via the
        Rust subsystem tree for now.

      - Allow 'ForeignOwnable' to carry information about the pointed-to
        type. This helps asserting alignment requirements for the
        pointer passed to the foreign language.

   - 'container_of!': retain pointer mut-ness and add a compile-time
     check of the type of the first parameter ('$field_ptr').

   - Support optional message in 'static_assert!'.

   - Add C FFI types (e.g. 'c_int') to the prelude.

   - 'str' module: simplify KUnit tests 'format!' macro, convert
     'rusttest' tests into KUnit, take advantage of the '-> Result'
     support in KUnit '#[test]'s.

   - 'list' module: add examples for 'List', fix path of
     'assert_pinned!' (so far unused macro rule).

   - 'workqueue' module: remove 'HasWork::OFFSET'.

   - 'page' module: add 'inline' attribute.

  'macros' crate:

   - 'module' macro: place 'cleanup_module()' in '.exit.text' section.

  'pin-init' crate:

   - Add 'Wrapper<T>' trait for creating pin-initializers for wrapper
     structs with a structurally pinned value such as 'UnsafeCell<T>' or
     'MaybeUninit<T>'.

   - Add 'MaybeZeroable' derive macro to try to derive 'Zeroable', but
     not error if not all fields implement it. This is needed to derive
     'Zeroable' for all bindgen-generated structs.

   - Add 'unsafe fn cast_[pin_]init()' functions to unsafely change the
     initialized type of an initializer. These are utilized by the
     'Wrapper<T>' implementations.

   - Add support for visibility in 'Zeroable' derive macro.

   - Add support for 'union's in 'Zeroable' derive macro.

   - Upstream dev news: streamline CI, fix some bugs. Add new workflows
     to check if the user-space version and the one in the kernel tree
     have diverged. Use the issues tab [1] to track them, which should
     help folks report and diagnose issues w.r.t. 'pin-init' better.

       [1] https://github.com/rust-for-linux/pin-init/issues

  Documentation:

   - Testing: add docs on the new KUnit '#[test]' tests.

   - Coding guidelines: explain that '///' vs. '//' applies to private
     items too. Add section on C FFI types.

   - Quick Start guide: update Ubuntu instructions and split them into
     "25.04" and "24.04 LTS and older".

  And a few other cleanups and improvements"

* tag 'rust-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: (78 commits)
  rust: list: Fix typo `much` in arc.rs
  rust: check type of `$ptr` in `container_of!`
  rust: workqueue: remove HasWork::OFFSET
  rust: retain pointer mut-ness in `container_of!`
  Documentation: rust: testing: add docs on the new KUnit `#[test]` tests
  Documentation: rust: rename `#[test]`s to "`rusttest` host tests"
  rust: str: take advantage of the `-> Result` support in KUnit `#[test]`'s
  rust: str: simplify KUnit tests `format!` macro
  rust: str: convert `rusttest` tests into KUnit
  rust: add `kunit_tests` to the prelude
  rust: kunit: support checked `-> Result`s in KUnit `#[test]`s
  rust: kunit: support KUnit-mapped `assert!` macros in `#[test]`s
  rust: make section names plural
  rust: list: fix path of `assert_pinned!`
  rust: compile libcore with edition 2024 for 1.87+
  rust: dma: add missing Markdown code span
  rust: task: add missing Markdown code spans and intra-doc links
  rust: pci: fix docs related to missing Markdown code spans
  rust: alloc: add missing Markdown code span
  rust: alloc: add missing Markdown code spans
  ...

Pull more MM updates from Andrew Morton:

 - "zram: support algorithm-specific parameters" from Sergey Senozhatsky
   adds infrastructure for passing algorithm-specific parameters into
   zram. A single parameter `winbits' is implemented at this time.

 - "memcg: nmi-safe kmem charging" from Shakeel Butt makes memcg
   charging nmi-safe, which is required by BFP, which can operate in NMI
   context.

 - "Some random fixes and cleanup to shmem" from Kemeng Shi implements
   small fixes and cleanups in the shmem code.

 - "Skip mm selftests instead when kernel features are not present" from
   Zi Yan fixes some issues in the MM selftest code.

 - "mm/damon: build-enable essential DAMON components by default" from
   SeongJae Park reworks DAMON Kconfig to make it easier to enable
   CONFIG_DAMON.

 - "sched/numa: add statistics of numa balance task migration" from Libo
   Chen adds more info into sysfs and procfs files to improve visibility
   into the NUMA balancer's task migration activity.

 - "selftests/mm: cow and gup_longterm cleanups" from Mark Brown
   provides various updates to some of the MM selftests to make them
   play better with the overall containing framework.

* tag 'mm-stable-2025-06-01-14-06' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (43 commits)
  mm/khugepaged: clean up refcount check using folio_expected_ref_count()
  selftests/mm: fix test result reporting in gup_longterm
  selftests/mm: report unique test names for each cow test
  selftests/mm: add helper for logging test start and results
  selftests/mm: use standard ksft_finished() in cow and gup_longterm
  selftests/damon/_damon_sysfs: skip testcases if CONFIG_DAMON_SYSFS is disabled
  sched/numa: add statistics of numa balance task
  sched/numa: fix task swap by skipping kernel threads
  tools/testing: check correct variable in open_procmap()
  tools/testing/vma: add missing function stub
  mm/gup: update comment explaining why gup_fast() disables IRQs
  selftests/mm: two fixes for the pfnmap test
  mm/khugepaged: fix race with folio split/free using temporary reference
  mm: add CONFIG_PAGE_BLOCK_ORDER to select page block order
  mmu_notifiers: remove leftover stub macros
  selftests/mm: deduplicate test names in madv_populate
  kcov: rust: add flags for KCOV with Rust
  mm: rust: make CONFIG_MMU ifdefs more narrow
  mmu_gather: move tlb flush for VM_PFNMAP/VM_MIXEDMAP vmas into free_pgtables()
  mm/damon/Kconfig: enable CONFIG_DAMON by default
  ...

Pull vfs fixes from Christian Brauner:

 - Fix the AT_HANDLE_CONNECTABLE option so filesystems that don't know
   how to decode a connected non-dir dentry fail the request

 - Use repr(transparent) to ensure identical layout between the C and
   Rust implementation of struct file

 - Add a missing xas_pause() into the dax code employing
   wait_entry_unlocked_exclusive()

 - Fix FOP_DONTCACHE which we disabled for v6.15.

   A folio could get redirtied and/or scheduled for writeback after the
   initial dropbehind test. Change the test accordingly to handle these
   cases so we can re-enable FOP_DONTCACHE again

* tag 'vfs-6.16-rc2.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  exportfs: require ->fh_to_parent() to encode connectable file handles
  rust: file: improve safety comments
  rust: file: mark `LocalFile` as `repr(transparent)`
  fs/dax: Fix "don't skip locked entries when scanning entries"
  iomap: don't lose folio dropbehind state for overwrites
  mm/filemap: unify dropbehind flag testing and clearing
  mm/filemap: unify read/write dropbehind naming
  Revert "Disable FOP_DONTCACHE for now due to bugs"
  mm/filemap: use filemap_end_dropbehind() for read invalidation
  mm/filemap: gate dropbehind invalidate on folio !dirty && !writeback