If `CONFIG_PRINTK` is not set, then the following warnings are issued
during build:

  warning: unused variable: `args`
    --> ../rust/kernel/kunit.rs:16:12
    |
  16 | pub fn err(args: fmt::Arguments<'_>) {
    |            ^^^^ help: if this is intentional, prefix it with an underscore: `_args`
    |
    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default

  warning: unused variable: `args`
    --> ../rust/kernel/kunit.rs:32:13
    |
  32 | pub fn info(args: fmt::Arguments<'_>) {
    |             ^^^^ help: if this is intentional, prefix it with an underscore: `_args`

Fix this by adding a no-op assignment using `args` when `CONFIG_PRINTK`
is not set.

Fixes: a66d733da801 ("rust: support running Rust documentation tests as KUnit ones")
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: David Gow <david@davidgow.net>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

The last null element can be created (constly) using `pin_init::zeroed`,
so prefer to use it instead of adding a custom way of building it.

Reviewed-by: Tamir Duberstein <tamird@gmail.com>
Reviewed-by: Benno Lossin <lossin@kernel.org>
Signed-off-by: Gary Guo <gary@garyguo.net>
Reviewed-by: David Gow <davidgow@google.com>
Link: https://patch.msgid.link/20260112170919.1888584-12-gary@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Some doc comments use `NULL` while others use plain NULL.  Make it
consistent by adding backticks everywhere, matching the majority of
existing usage.

Signed-off-by: Peter Novak <seimun018r@gmail.com>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Acked-by: David Gow <davidgow@google.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://patch.msgid.link/20251130211233.367946-1-seimun018r@gmail.com
[ Reworded slightly. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

C-String literals were added in Rust 1.77. Replace instances of
`kernel::c_str!` with C-String literals where possible.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <lossin@kernel.org>
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Reviewed-by: David Gow <davidgow@google.com>
Link: https://patch.msgid.link/20251222-cstr-kunit-v1-1-39d999672f35@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Pull kunit updates from Shuah Khan:

 - New parameterized test features

   KUnit parameterized tests supported two primary methods for getting
   parameters:

    - Defining custom logic within a generate_params() function.

    - Using the KUNIT_ARRAY_PARAM() and KUNIT_ARRAY_PARAM_DESC() macros
      with a pre-defined static array and passing the created
      *_gen_params() to KUNIT_CASE_PARAM().

   These methods present limitations when dealing with dynamically
   generated parameter arrays, or in scenarios where populating
   parameters sequentially via generate_params() is inefficient or
   overly complex.

   These limitations are fixed with a parameterized test method

 - Fix issues in kunit build artifacts cleanup

 - Fix parsing skipped test problem in kselftest framework

 - Enable PCI on UML without triggering WARN()

 - a few other fixes and adds support for new configs such as MIPS

* tag 'linux_kselftest-kunit-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
  kunit: Extend kconfig help text for KUNIT_UML_PCI
  rust: kunit: allow `cfg` on `test`s
  kunit: qemu_configs: Add MIPS configurations
  kunit: Enable PCI on UML without triggering WARN()
  Documentation: kunit: Document new parameterized test features
  kunit: Add example parameterized test with direct dynamic parameter array setup
  kunit: Add example parameterized test with shared resource management using the Resource API
  kunit: Enable direct registration of parameter arrays to a KUnit test
  kunit: Pass parameterized test context to generate_params()
  kunit: Introduce param_init/exit for parameterized test context management
  kunit: Add parent kunit for parameterized test context
  kunit: tool: Accept --raw_output=full as an alias of 'all'
  kunit: tool: Parse skipped tests from kselftest.h
  kunit: Always descend into kunit directory during build

The `kunit_test` proc macro only checks for the `test` attribute
immediately preceding a `fn`. If the function is disabled via a `cfg`,
the generated code would result in a compile error referencing a
non-existent function [1].

This collects attributes and specifically cherry-picks `cfg` attributes
to be duplicated inside KUnit wrapper functions such that a test function
disabled via `cfg` compiles and is marked as skipped in KUnit correctly.

Link: https://lore.kernel.org/r/20250916021259.115578-1-ent3rm4n@gmail.com
Link: https://lore.kernel.org/rust-for-linux/CANiq72==48=69hYiDo1321pCzgn_n1_jg=ez5UYXX91c+g5JVQ@mail.gmail.com/ [1]
Closes: https://github.com/Rust-for-Linux/linux/issues/1185
Suggested-by: Miguel Ojeda <ojeda@kernel.org>
Suggested-by: David Gow <davidgow@google.com>
Signed-off-by: Kaibo Ma <ent3rm4n@gmail.com>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

Prepare for `core::ffi::CStr` taking the place of `kernel::str::CStr` by
avoid methods that only exist on the latter.

Link: https://github.com/Rust-for-Linux/linux/issues/1075
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <lossin@kernel.org>
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Reduce coupling to implementation details of the formatting machinery by
avoiding direct use for `core`'s formatting traits and macros.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <lossin@kernel.org>
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Add (*param_init) and (*param_exit) function pointers to
`struct kunit_case`. Users will be able to set them via the new
KUNIT_CASE_PARAM_WITH_INIT() macro.

param_init/exit will be invoked by kunit_run_tests() once before and once
after the parameterized test, respectively. They will receive the
`struct kunit` that holds the parameterized test context; facilitating
init and exit for shared state.

This patch also sets param_init/exit to None in rust/kernel/kunit.rs.

Link: https://lore.kernel.org/r/20250826091341.1427123-3-davidgow@google.com
Reviewed-by: Rae Moar <rmoar@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Marie Zhussupova <marievic@google.com>
Signed-off-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

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

   - Enable a set of Clippy lints: 'ptr_as_ptr', 'ptr_cast_constness',
     'as_ptr_cast_mut', 'as_underscore', 'cast_lossless' and
     'ref_as_ptr'

     These are intended to avoid type casts with the 'as' operator,
     which are quite powerful, into restricted variants that are less
     powerful and thus should help to avoid mistakes

   - Remove the 'author' key now that most instances were moved to the
     plural one in the previous cycle

  'kernel' crate:

   - New 'bug' module: add 'warn_on!' macro which reuses the existing
     'BUG'/'WARN' infrastructure, i.e. it respects the usual sysctls and
     kernel parameters:

         warn_on!(value == 42);

     To avoid duplicating the assembly code, the same strategy is
     followed as for the static branch code in order to share the
     assembly between both C and Rust

     This required a few rearrangements on C arch headers -- the
     existing C macros should still generate the same outputs, thus no
     functional change expected there

   - 'workqueue' module: add delayed work items, including a
     'DelayedWork' struct, a 'impl_has_delayed_work!' macro and an
     'enqueue_delayed' method, e.g.:

         /// Enqueue the struct for execution on the system workqueue,
         /// where its value will be printed 42 jiffies later.
         fn print_later(value: Arc<MyStruct>) {
             let _ = workqueue::system().enqueue_delayed(value, 42);
         }

   - New 'bits' module: add support for 'bit' and 'genmask' functions,
     with runtime- and compile-time variants, e.g.:

         static_assert!(0b00010000 == bit_u8(4));
         static_assert!(0b00011110 == genmask_u8(1..=4));

         assert!(checked_bit_u32(u32::BITS).is_none());

   - 'uaccess' module: add 'UserSliceReader::strcpy_into_buf', which
     reads NUL-terminated strings from userspace into a '&CStr'

     Introduce 'UserPtr' newtype, similar in purpose to '__user' in C,
     to minimize mistakes handling userspace pointers, including mixing
     them up with integers and leaking them via the 'Debug' trait. Add
     it to the prelude, too

   - Start preparations for the replacement of our custom 'CStr' type
     with the analogous type in the 'core' standard library. This will
     take place across several cycles to make it easier. For this one,
     it includes a new 'fmt' module, using upstream method names and
     some other cleanups

     Replace 'fmt!' with a re-export, which helps Clippy lint properly,
     and clean up the found 'uninlined-format-args' instances

   - 'dma' module:

      - Clarify wording and be consistent in 'coherent' nomenclature

      - Convert the 'read!()' and 'write!()' macros to return a 'Result'

      - Add 'as_slice()', 'write()' methods in 'CoherentAllocation'

      - Expose 'count()' and 'size()' in 'CoherentAllocation' and add
        the corresponding type invariants

      - Implement 'CoherentAllocation::dma_handle_with_offset()'

   - 'time' module:

      - Make 'Instant' generic over clock source. This allows the
        compiler to assert that arithmetic expressions involving the
        'Instant' use 'Instants' based on the same clock source

      - Make 'HrTimer' generic over the timer mode. 'HrTimer' timers
        take a 'Duration' or an 'Instant' when setting the expiry time,
        depending on the timer mode. With this change, the compiler can
        check the type matches the timer mode

      - Add an abstraction for 'fsleep'. 'fsleep' is a flexible sleep
        function that will select an appropriate sleep method depending
        on the requested sleep time

      - Avoid 64-bit divisions on 32-bit hardware when calculating
        timestamps

      - Seal the 'HrTimerMode' trait. This prevents users of the
        'HrTimerMode' from implementing the trait on their own types

      - Pass the correct timer mode ID to 'hrtimer_start_range_ns()'

   - 'list' module: remove 'OFFSET' constants, allowing to remove
     pointer arithmetic; now 'impl_list_item!' invokes
     'impl_has_list_links!' or 'impl_has_list_links_self_ptr!'. Other
     simplifications too

   - 'types' module: remove 'ForeignOwnable::PointedTo' in favor of a
     constant, which avoids exposing the type of the opaque pointer, and
     require 'into_foreign' to return non-null

     Remove the 'Either<L, R>' type as well. It is unused, and we want
     to encourage the use of custom enums for concrete use cases

   - 'sync' module: implement 'Borrow' and 'BorrowMut' for 'Arc' types
     to allow them to be used in generic APIs

   - 'alloc' module: implement 'Borrow' and 'BorrowMut' for 'Box<T, A>';
     and 'Borrow', 'BorrowMut' and 'Default' for 'Vec<T, A>'

   - 'Opaque' type: add 'cast_from' method to perform a restricted cast
     that cannot change the inner type and use it in callers of
     'container_of!'. Rename 'raw_get' to 'cast_into' to match it

   - 'rbtree' module: add 'is_empty' method

   - 'sync' module: new 'aref' submodule to hold 'AlwaysRefCounted' and
     'ARef', which are moved from the too general 'types' module which
     we want to reduce or eventually remove. Also fix a safety comment
     in 'static_lock_class'

  'pin-init' crate:

   - Add 'impl<T, E> [Pin]Init<T, E> for Result<T, E>', so results are
     now (pin-)initializers

   - Add 'Zeroable::init_zeroed()' that delegates to 'init_zeroed()'

   - New 'zeroed()', a safe version of 'mem::zeroed()' and also provide
     it via 'Zeroable::zeroed()'

   - Implement 'Zeroable' for 'Option<&T>', 'Option<&mut T>' and for
     'Option<[unsafe] [extern "abi"] fn(...args...) -> ret>' for
     '"Rust"' and '"C"' ABIs and up to 20 arguments

   - Changed blanket impls of 'Init' and 'PinInit' from 'impl<T, E>
     [Pin]Init<T, E> for T' to 'impl<T> [Pin]Init<T> for T'

   - Renamed 'zeroed()' to 'init_zeroed()'

   - Upstream dev news: improve CI more to deny warnings, use
     '--all-targets'. Check the synchronization status of the two
     '-next' branches in upstream and the kernel

  MAINTAINERS:

   - Add Vlastimil Babka, Liam R. Howlett, Uladzislau Rezki and Lorenzo
     Stoakes as reviewers (thanks everyone)

  And a few other cleanups and improvements"

* tag 'rust-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: (76 commits)
  rust: Add warn_on macro
  arm64/bug: Add ARCH_WARN_ASM macro for BUG/WARN asm code sharing with Rust
  riscv/bug: Add ARCH_WARN_ASM macro for BUG/WARN asm code sharing with Rust
  x86/bug: Add ARCH_WARN_ASM macro for BUG/WARN asm code sharing with Rust
  rust: kernel: move ARef and AlwaysRefCounted to sync::aref
  rust: sync: fix safety comment for `static_lock_class`
  rust: types: remove `Either<L, R>`
  rust: kernel: use `core::ffi::CStr` method names
  rust: str: add `CStr` methods matching `core::ffi::CStr`
  rust: str: remove unnecessary qualification
  rust: use `kernel::{fmt,prelude::fmt!}`
  rust: kernel: add `fmt` module
  rust: kernel: remove `fmt!`, fix clippy::uninlined-format-args
  scripts: rust: emit path candidates in panic message
  scripts: rust: replace length checks with match
  rust: list: remove nonexistent generic parameter in link
  rust: bits: add support for bits/genmask macros
  rust: list: remove OFFSET constants
  rust: list: add `impl_list_item!` examples
  rust: list: use fully qualified path
  ...