87 Commits
Author SHA1 Message Date
Gary Guo b6b9e6d4ab rust: pin-init: use irrefutable pattern for stack_pin_init
In Rust 1.100.0, `Infallible` will become an alias of `!`. The let
binding in `stack_pin_init` will thus become unreachable and produce
an "unreachable expression" warning for the subsequent match, and thus
will fail a `-Dwarnings` build. For this macro, all we need to know is
that the error type is uninhabited, so replace this with an irrefutable
pattern instead.

[ The error looks like (dummy reproducer):

      error: unreachable expression
         --> rust/kernel/sync.rs:177:5
          |
      177 |     pin_init::stack_pin_init!(let num = 42u32);
          |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
          |     |
          |     unreachable expression
          |     any code following this expression is unreachable
          |
          = note: `-D unreachable-code` implied by `-D warnings`
          = help: to override `-D warnings` add `#[allow(unreachable_code)]`
          = note: this error originates in the macro `pin_init::stack_pin_init` (in Nightly builds, run with -Z macro-backtrace for more info)

    - Miguel ]

Reported-by: Mohamad Alsadhan <[email protected]>
Closes: https://github.com/Rust-for-Linux/pin-init/pull/171
Signed-off-by: Gary Guo <[email protected]>
Cc: [email protected] # Needed in 7.1.y and later (for 6.12.y and 6.18.y a custom one is needed).
Link: https://patch.msgid.link/[email protected]
[ Reworded for typos. - Miguel ]
Signed-off-by: Miguel Ojeda <[email protected]>
2026-09-01 01:27:55 +02:00
Gary Guo 1e26aea035 rust: pin-init: add #[inline] to small functions
Currently `pin-init` crate is missing many inline annotations. They are all
generic so still get inlined in normal builds, but are not inlined in
`-C opt-level=s` build. Mark these functions as `#[inline]` so they are
considered for inlining regardless.

Signed-off-by: Gary Guo <[email protected]>
2026-08-05 11:36:18 +01:00
Gary Guo 1f7fa1374d rust: pin-init: remove __pinned_init method for cfg(kernel)
Remove `__pinned_init` for kernel configuration, with all users gone.
Still perserve it temporarily as deprecated so other users have time to
move off it.

Link: https://patch.msgid.link/[email protected]
Signed-off-by: Gary Guo <[email protected]>
2026-08-05 11:36:18 +01:00
Gary Guo d5492db2bf rust: pin-init: add raw_init and raw_try_init and recommend over __init
The `__init` method is not designed to be a public API (existence of "__"
is a hint for this); but currently there is no other API that allows raw
initialization on pointers. Add `raw_init` and `raw_try_init` and recommend
people to use this instead if raw pointer initialization is needed.

Link: https://patch.msgid.link/[email protected]
[ Renamed from `ptr_[try_]init` to `raw_[try_]init`. - Gary ]
Reviewed-by: Benno Lossin <[email protected]>
Signed-off-by: Gary Guo <[email protected]>
2026-08-05 11:36:16 +01:00
Gary Guo 91665820d9 rust: pin-init: merge __pinned_init and __init
These functions have the same requirements and are also required to execute
the same code. Prevent duplication by merging them to the single function
and document the additional relaxation of `Init::__init` on both the merged
function and the safety requirement of `Init`.

The existing `__pinned_init` function is deprecated and kept for
compatibility for existing users. For `cfg(kernel)`, it is soft-deprecated
for now and will be removed when all users are migrated.

Link: https://patch.msgid.link/[email protected]
Signed-off-by: Gary Guo <[email protected]>
2026-08-03 13:36:42 +01:00
Nicolás Antinori 6d0795b507 rust: pin-init: mark pin_init::zeroed and Zeroable::zeroed as #[inline]
The `pin_init::zeroed` function is a trivial wrapper around
`unsafe { core::mem::zeroed() }`, whereas `Zeroable::zeroed` is a trivial
wrapper around `pin_init::zeroed`. Mark them both as `#[inline]` to avoid
generating unnecessary symbols for them.

Signed-off-by: Nicolás Antinori <[email protected]>
Signed-off-by: Gary Guo <[email protected]>
2026-07-27 11:52:08 +01:00
Nicolás Antinori 9e813b9abd rust: pin-init: docs: link Zeroable::zeroed and pin_init::zeroed in documentation
Modify the comments in the `pin_init::zeroed` and `Zeroable::zeroed`
functions to cross-reference each other and make developers aware of both
options.

This also adapts the example code in `Zeroable::zeroed` doc comments to use
that function.

Suggested-by: Miguel Ojeda <[email protected]>
Link: https://lore.kernel.org/rust-for-linux/CANiq72kdCAyRUmXFcqQfkHpk1miG8Gagsn0_5U8p4WpKxv9d_g@mail.gmail.com/
Signed-off-by: Nicolás Antinori <[email protected]>
[ Fix link. - Gary ]
Signed-off-by: Gary Guo <[email protected]>
2026-07-27 11:52:08 +01:00
Mirko Adzic 0c20f77a26 rust: pin-init: make [pin_]chain unwind safe
Add a drop guard before the call to the chained closure so that the value
initialized by the first stage is dropped if the closure errors or panics;
`mem::forget` the guard on success.

The previous code only ran cleanup on the explicit error path, leaking the
first-stage value if the chained closure panicked.

Reported-by: Gary Guo <[email protected]>
Closes: https://github.com/Rust-for-Linux/pin-init/issues/136
Suggested-by: Gary Guo <[email protected]>
Signed-off-by: Mirko Adzic <[email protected]>
Link: https://patch.msgid.link/[email protected]
[ Fix Clippy missing safety comment false positive when `slot` and `guard`
  creation are merged in a single line. - Gary ]
Signed-off-by: Gary Guo <[email protected]>
2026-07-13 12:11:44 +01:00
Mirko Adzic 7e4d9c946d rust: pin-init: make [pin_]init_array_from_fn unwind safe
The previous code only ran cleanup on the explicit error path. If the per-
element initializer panicked partway through, the elements already written
into the array would be leaked: their `Drop` impls would never run. This
violates the pinning requirement.

Fix the unwind safety issue by adding a guard type that drops element on
both error and panic path.

To avoid having to duplicate code between `pin_init_array_from_fn` and the
non-pin variant, extract the code to a shared `ArrayInit` type; this type
is internal and not visible via API.

Reported-by: Gary Guo <[email protected]>
Closes: https://github.com/Rust-for-Linux/pin-init/issues/136
Signed-off-by: Mirko Adzic <[email protected]>
Link: https://patch.msgid.link/[email protected]
[ Split guard type and the initializer type, move the guard type to be
  within __pinned_init. - Gary ]
Co-developed-by: Gary Guo <[email protected]>
Signed-off-by: Gary Guo <[email protected]>
2026-07-13 12:11:29 +01:00
Gary Guo 690d82bf1d rust: pin-init: remove redundant clippy expects in doc tests
These lints are automatically suppressed inside doc tests. Previously this
is needed because kernel builds doc tests with the default set of clippy
flags; but now `clippy::disallowed_names` is globally allowed inside doc
tests.

Reviewed-by: Benno Lossin <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Gary Guo <[email protected]>
2026-07-13 12:10:00 +01:00
Gary Guo f85906616e rust: pin-init: remove E from InitClosure
Move `E` from type to trait impl block. This greatly shortens the
monomorphized type names. The `__pinned_init` function name is only
slightly shortened as it still encodes the `E` as part of `PinInit<T, E>`
in the symbol.

`T` cannot be moved to trait impl block otherwise it will start to conflict
with the `impl Init<T> for T` as Rust cannot deduce that there're no types
that fulfill `T: FnOnce(*mut T)`.

Link: https://patch.msgid.link/[email protected]
Signed-off-by: Gary Guo <[email protected]>
2026-05-29 21:34:53 +01:00
Gary Guo 79bc923ae2 rust: pin-init: move InitClosure out from __internal
The `__internal` module is for exposing internal items publicly to
procedural macros (pin-init-internal). Types that are crate-local only can
just have proper visibility and does not need to be in `__internal`.

The type name of `InitClosure` can often shows up in symbol names, this
reduces the length slightly.

Link: https://patch.msgid.link/[email protected]
Signed-off-by: Gary Guo <[email protected]>
2026-05-29 21:34:53 +01:00
Xiaobo Liu 2a02b4f96f rust: pin-init: docs: fix typos in MaybeZeroable documentation
Signed-off-by: Xiaobo Liu <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Gary Guo <[email protected]>
2026-05-29 21:34:53 +01:00
Gary Guo 6fb5912c92 rust: pin-init: internal: project using full slot
Instead of projecting using pointer to a field project the full slot. This
further shifts the code generation from the initializer site to the struct
definition site, which means less code is generated overall.

It also makes the safety comment easier to justify, as now the projection
is done by the `#[pin_data]` macro which has full visibility of pinnedness
of fields.

The field alignment could also be checked on the `#[pin_data]` side;
however, since `init!()` macro works for other type of structs, we cannot
remove the alignment check from `init!`/`pin_init!` side anyway, so I opted
to still keep the alignment check in init.rs.

Signed-off-by: Gary Guo <[email protected]>
2026-05-18 12:21:28 +01:00
Gary Guo 5483a97dd2 rust: pin-init: internal: project slots instead of references
By projecting slots, the `pin_init!` and `init!` code path can be more
unified. This also reduces the amount of macro-generated code and shifts
them to the shared infrastructure.

Signed-off-by: Gary Guo <[email protected]>
2026-05-18 12:21:13 +01:00
Gary Guo 57b0a0d7e5 rust: pin-init: internal: make make_closure inherent methods
The `InitData` and `PinData` traits do not need to exist, the inference
helpers could be inherent methods instead.

There is no risk for calling the wrong methods even when user defines it,
as inherent methods take priority over trait methods.

With this change, it unlocks the possibility of attaching additional bounds
to the method per type, which is not possible for trait methods.

Signed-off-by: Gary Guo <[email protected]>
2026-05-18 12:18:06 +01:00
Gary Guo 27693a56e8 rust: pin-init: internal: use marker on drop guard type for pinned fields
Instead of projecting the created reference, simply create drop guards with
different marker types and have the `let_binding()` method of guards of
different marker produce different type instead.

This allows more flexible lifetime as this is now controlled by the guard.
This will be needed when implementing self-referential fields.

Signed-off-by: Gary Guo <[email protected]>
2026-05-18 12:18:06 +01:00
Gary Guo fea304ec87 rust: pin-init: internal: add PhantomInvariant and PhantomInvariantLifetime
Currently, the `pin_init` library has an `Invariant` type alias, and it is
instantiated using `PhantomData`. Generated code from `pin_data` on the
other hand cannot access the crate-local type alias, so it generates
`PhantomData<fn(T) -> T>` directly. This is all very inconsistent, despite
the exact same use case of ensuring invariance.

Add `PhantomInvariant` and `PhantomInvariantLifetime` and switch all users
that need to express the concept of invariance to use these. They're
polyfills of unstable types in the same names in the Rust standard library.

Link: https://patch.msgid.link/[email protected]
Signed-off-by: Gary Guo <[email protected]>
2026-05-14 20:18:14 +01:00
Gary Guo 3dc01266cd rust: pin-init: cleanup workaround for old Rust compiler
The workaround mentions it's for Rust versions before 1.81. The minimum is
now 1.82, thus clean up.

Link: https://patch.msgid.link/[email protected]
Signed-off-by: Gary Guo <[email protected]>
2026-05-10 22:58:34 +01:00
Mohamad Alsadhan de54c2cb05 rust: pin-init: extend impl_zeroable_option macro to handle generics
Improve impl_zeroable_option macro to handle generic impls for types
like `&T`, `&mut T`, `NonNull<T>`, and others (for which `Option<T>`
is guaranteed to be zeroable) with similar approach to
`impl_zeroable`.

Also, update old declarations to use generics e.g. `NonZeroU8` to
`NonZero<u8>`.

Signed-off-by: Mohamad Alsadhan <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Gary Guo <[email protected]>
2026-05-10 22:58:33 +01:00
Mohamad Alsadhan 04828a538d rust: pin-init: cleanup Zeroable and ZeroableOptions
Place definitions and implementations (incl. macro invocations) of
the `Zeroable` trait first in the relevant section of `src/lib.rs`,
followed by the ZeroableOption trait and its implementations.

Rename `impl_non_zero_int_zeroable_option` to `impl_zeroable_option`
for consistency.

This commit should not introduce any functional changes.

Signed-off-by: Mohamad Alsadhan <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Gary Guo <[email protected]>
2026-05-10 22:58:33 +01:00
Gary Guo 531fdc2c34 rust: pin-init: bump minimum Rust version to 1.82
Following the kernel minimum version bump in commit f32fb9c58a ("rust:
bump Rust minimum supported version to 1.85.0 (Debian Trixie)"), bump
pin-init's minimum Rust version to 1.82.

This removes the `lint_reasons` feature which is stabilized in 1.81 and the
`raw_ref_ops` and `new_uninit` features which are stabilized in 1.82.

Given we do not use any features that are stabilized in 1.82..=1.85 range,
and pin-init crate is useful for other projects which may have their own
MSRV requirements, the minimum version is not straightly bumped to 1.85.

Reviewed-by: Benno Lossin <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Gary Guo <[email protected]>
2026-05-10 22:58:33 +01:00
Gary Guo 68bf102226 rust: pin-init: fix incorrect accessor reference lifetime
When a field has been initialized, `init!`/`pin_init!` create a reference
or pinned reference to the field so it can be accessed later during the
initialization of other fields. However, the reference it created is
incorrectly `&'static` rather than just the scope of the initializer.

This means that you can do

    init!(Foo {
        a: 1,
        _: {
            let b: &'static u32 = a;
        }
    })

which is unsound.

This is caused by `&mut (*#slot).#ident`, which actually allows arbitrary
lifetime, so this is effectively `'static`. Somewhat ironically, the safety
justification of creating the accessor is.. "SAFETY: TODO".

Fix it by adding `let_binding` method on `DropGuard` to shorten lifetime.
This results in exactly what we want for these accessors. The safety and
invariant comments of `DropGuard` have been reworked; instead of reasoning
about what caller can do with the guard, express it in a way that the
ownership is transferred to the guard and `forget` takes it back, so the
unsafe operations within the `DropGuard` can be more easily justified.

Fixes: 42415d163e ("rust: pin-init: add references to previously initialized fields")
Cc: [email protected]
Signed-off-by: Gary Guo <[email protected]>
Link: https://patch.msgid.link/[email protected]
[ Reworded for missing word. - Miguel ]
Signed-off-by: Miguel Ojeda <[email protected]>
2026-04-30 22:43:32 +02:00
Antonio Hickey 09808839c7 rust: pin-init: replace addr_of_mut! with &raw mut
`feature(raw_ref_op)` became stable in Rust 1.82.0 which is the current
MSRV of pin-init with no default features. Earlier Rust versions will
now need to enable `raw_ref_op` to continue to work with pin-init.

This reduces visual complexity and improves consistency with existing
reference syntax.

Suggested-by: Benno Lossin <[email protected]>
Link: https://github.com/Rust-for-Linux/linux/issues/1148
Closes: https://github.com/Rust-for-Linux/pin-init/issues/99
Signed-off-by: Antonio Hickey <[email protected]>
Link: https://github.com/Rust-for-Linux/pin-init/commit/e27763004e2f6616b089437fbe9b3719cd72bd5c
[ Reworded commit message. - Benno ]
Reviewed-by: Gary Guo <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Benno Lossin <[email protected]>
2026-03-25 10:57:53 +01:00
Hamdan-Khan aa9ec9460d rust: pin-init: implement ZeroableOption for NonZero* integer types
Add a macro for implementing `ZeroableOption` for `NonZero*` types.

`Option<NonZero*>` now automatically implements `Zeroable` trait  by
implementing `ZeroableOption` for `NonZero*` types, which serves as a
blanket impl.

Closes: https://github.com/Rust-for-Linux/pin-init/issues/95
Signed-off-by: Hamdan-Khan <[email protected]>
Link: https://github.com/Rust-for-Linux/pin-init/commit/74f772641cd9670848fa360f4ebfd20fdb40bf78
[ Fixed a typo in the commit message. - Benno ]
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Benno Lossin <[email protected]>
2026-03-25 10:57:33 +01:00
Gary Guo 44f6fa0dce rust: pin-init: doc: de-clutter documentation with fake-variadics
Currently the doc for `Zeroable` and `ZeroableOption` are filled with the
generated impl of tuples and fn pointers. Use the internal
"fake_variadics" feature to improve the rendered quality.

This makes use of an internal feature, however this is of minimal risk as
it's for documentation only, not activated during normal build, gated
behind `USE_RUSTC_FEATURES`, and can be removed at any time. This feature
is already used by serde and bevy to improve documentation quality.

For compilers that cannot use this feature, we still hide most generated
impls, and the existence of them are hinted by doc comments on the single
non-hidden impl.

Signed-off-by: Gary Guo <[email protected]>
Link: https://github.com/Rust-for-Linux/pin-init/commit/530c4eb79a449599e219821f9397f03250cc2aa4
[ Reordered `#[doc]` attributes and safety comments to avoid errors in
  older versions of clippy. - Benno ]
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Benno Lossin <[email protected]>
2026-03-25 10:57:16 +01:00
Benno Lossin 960c37cbcb rust: pin-init: properly document let binding workaround
The three let bindings (in the bodies of `cast_init`, `cast_pin_init`
and the `init!` macro) are used to avoid the following compiler error in
Rust 1.78.0, 1.79.0, 1.80.0, 1.80.1, and 1.81.0 (just showing the one
for `cast_init`, the others are similar):

    error[E0391]: cycle detected when computing type of opaque `cast_init::{opaque#0}`
        --> src/lib.rs:1160:66
         |
    1160 | pub const unsafe fn cast_init<T, U, E>(init: impl Init<T, E>) -> impl Init<U, E> {
         |                                                                  ^^^^^^^^^^^^^^^
         |
    note: ...which requires borrow-checking `cast_init`...
        --> src/lib.rs:1160:1
         |
    1160 | pub const unsafe fn cast_init<T, U, E>(init: impl Init<T, E>) -> impl Init<U, E> {
         | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    note: ...which requires const checking `cast_init`...
        --> src/lib.rs:1160:1
         |
    1160 | pub const unsafe fn cast_init<T, U, E>(init: impl Init<T, E>) -> impl Init<U, E> {
         | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
         = note: ...which requires computing whether `cast_init::{opaque#0}` is freeze...
         = note: ...which requires evaluating trait selection obligation `cast_init::{opaque#0}: core::marker::Freeze`...
         = note: ...which again requires computing type of opaque `cast_init::{opaque#0}`, completing the cycle
    note: cycle used when computing type of `cast_init::{opaque#0}`
        --> src/lib.rs:1160:66
         |
    1160 | pub const unsafe fn cast_init<T, U, E>(init: impl Init<T, E>) -> impl Init<U, E> {
         |                                                                  ^^^^^^^^^^^^^^^
         = note: see https://rustc-dev-guide.rust-lang.org/overview.html#queries and https://rustc-dev-guide.rust-lang.org/query.html for more information

Once we raise the nightly-MSRV above 1.81, we can remove this
workaround.

Link: https://github.com/Rust-for-Linux/pin-init/commit/bb3e96f3e9a4f5fca80a22af883c7e5aa90f0893
[ Moved this commit after the previous one to avoid a build failure due
  to unstable features. Changed the cfg to use `USE_RUSTC_FEAUTURES`.
  - Benno ]
Reviewed-by: Gary Guo <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Benno Lossin <[email protected]>
2026-03-25 10:56:53 +01:00
Gary Guo 002a121b16 rust: pin-init: build: simplify use of nightly features
We use some features that are already stable in later versions of Rust,
but only available as unstable features in older Rust versions that the
kernel needs to support.

Instead of checking if a feature is already stable, simply enable them
and allow the warning if the feature is already stable. This avoids the
need of hardcoding whether a feature has been stabilized at a given
version.

`#[feature(...)]` is used when cfg `USE_RUSTC_FEATURES` is enabled. The
build script automatically does this when a nightly compiler is detected
or `RUSTC_BOOTSTRAP` is set.

Signed-off-by: Gary Guo <[email protected]>
Link: https://github.com/Rust-for-Linux/pin-init/commit/885c5d83d7eb778a796d4a17380a0898b0d0a571
[ Added kernel build system changes to always enable USE_RUSTC_FEATURES.
  Moved this commit earlier (swapped with the next one) to avoid a build
  error. - Benno ]
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Benno Lossin <[email protected]>
2026-03-25 10:56:16 +01:00
Benno Lossin fdbaa9d2b7 rust: pin-init: replace shadowed return token by unsafe-to-create token
We use a unit struct `__InitOk` in the closure generated by the
initializer macros as the return value. We shadow it by creating a
struct with the same name again inside of the closure, preventing early
returns of `Ok` in the initializer (before all fields have been
initialized).

In the face of Type Alias Impl Trait (TAIT) and the next trait solver,
this solution no longer works [1]. The shadowed struct can be named
through type inference. In addition, there is an RFC proposing to add
the feature of path inference to Rust, which would similarly allow [2].

Thus remove the shadowed token and replace it with an `unsafe` to create
token.

The reason we initially used the shadowing solution was because an
alternative solution used a builder pattern. Gary writes [3]:

    In the early builder-pattern based InitOk, having a single InitOk
    type for token is unsound because one can launder an InitOk token
    used for one place to another initializer. I used a branded lifetime
    solution, and then you figured out that using a shadowed type would
    work better because nobody could construct it at all.

The laundering issue does not apply to the approach we ended up with
today.

With this change, the example by Tim Chirananthavat in [1] no longer
compiles and results in this error:

    error: cannot construct `pin_init::__internal::InitOk` with struct literal syntax due to private fields
      --> src/main.rs:26:17
       |
    26 |                 InferredType {}
       |                 ^^^^^^^^^^^^
       |
       = note: private field `0` that was not provided
    help: you might have meant to use the `new` associated function
       |
    26 -                 InferredType {}
    26 +                 InferredType::new()
       |

Applying the suggestion of using the `::new()` function, results in
another expected error:

    error[E0133]: call to unsafe function `pin_init::__internal::InitOk::new` is unsafe and requires unsafe block
      --> src/main.rs:26:17
       |
    26 |                 InferredType::new()
       |                 ^^^^^^^^^^^^^^^^^^^ call to unsafe function
       |
       = note: consult the function's documentation for information on how to avoid undefined behavior

Reported-by: Tim Chirananthavat <[email protected]>
Link: https://github.com/rust-lang/rust/issues/153535 [1]
Link: https://github.com/rust-lang/rfcs/pull/3444#issuecomment-4016145373 [2]
Link: https://github.com/rust-lang/rust/issues/153535#issuecomment-4017620804 [3]
Fixes: fc6c6baa1f ("rust: init: add initialization macros")
Cc: [email protected]
Signed-off-by: Benno Lossin <[email protected]>
Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Link: https://patch.msgid.link/[email protected]
[ Added period as mentioned. - Miguel ]
Signed-off-by: Miguel Ojeda <[email protected]>
2026-03-12 08:46:17 +01:00
Linus Torvalds 1dd419145d Merge tag 'rust-fixes-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux
Pull rust fixes from Miguel Ojeda:
 "Toolchain and infrastructure:

   - Pass '-Zunstable-options' flag required by the future Rust 1.95.0

   - Fix 'objtool' warning for Rust 1.84.0

  'kernel' crate:

   - 'irq' module: add missing bound detected by the future Rust 1.95.0

   - 'list' module: add missing 'unsafe' blocks and placeholder safety
     comments to macros (an issue for future callers within the crate)

  'pin-init' crate:

   - Clean Clippy warning that changed behavior in the future Rust
     1.95.0"

* tag 'rust-fixes-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux:
  rust: list: Add unsafe blocks for container_of and safety comments
  rust: pin-init: replace clippy `expect` with `allow`
  rust: irq: add `'static` bounds to irq callbacks
  objtool/rust: add one more `noreturn` Rust function
  rust: kbuild: pass `-Zunstable-options` for Rust 1.95.0
2026-02-22 08:43:31 -08:00
Benno Lossin a58b8764ae rust: pin-init: replace clippy expect with allow
`clippy` has changed behavior in [1] (Rust 1.95) where it no longer
warns about the `let_and_return` lint when a comment is placed between
the let binding and the return expression. Nightly thus fails to build,
because the expectation is no longer fulfilled.

Thus replace the expectation with an `allow`.

[ The errors were:

      error: this lint expectation is unfulfilled
          --> rust/pin-init/src/lib.rs:1279:10
           |
      1279 | #[expect(clippy::let_and_return)]
           |          ^^^^^^^^^^^^^^^^^^^^^^
           |
           = note: `-D unfulfilled-lint-expectations` implied by `-D warnings`
           = help: to override `-D warnings` add `#[allow(unfulfilled_lint_expectations)]`

      error: this lint expectation is unfulfilled
          --> rust/pin-init/src/lib.rs:1295:10
           |
      1295 | #[expect(clippy::let_and_return)]
           |          ^^^^^^^^^^^^^^^^^^^^^^

    - Miguel ]

Link: https://github.com/rust-lang/rust-clippy/pull/16461 [1]
Signed-off-by: Benno Lossin <[email protected]>
Cc: [email protected] # Needed in 6.18.y and later.
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>
2026-02-19 09:33:43 +01:00
Oleksandr Babak aeb5ecad53 rust: pin-init: Implement InPlaceWrite<T> for &'static mut MaybeUninit<T>
This feature allows users to use `&'static mut MaybeUninit<T>` as a
place to initialize the value. It mirrors an existing implemetation
for `Box<MaybeUninit>`, but enables users to use external allocation
mechanisms such as `static_cell` [1].

Signed-off-by: Oleksandr Babak <[email protected]>
Link: https://crates.io/crates/static_cell [1]
[ Added link to `static_cell` - Benno ]
Signed-off-by: Benno Lossin <[email protected]>
2026-01-17 10:53:28 +01:00
Benno Lossin 4883830e97 rust: pin-init: rewrite the initializer macros using syn
Rewrite the initializer macros `[pin_]init!` using `syn`. No functional
changes intended aside from improved error messages on syntactic and
semantical errors. For example if one forgets to use `<-` with an
initializer (and instead uses `:`):

    impl Bar {
        fn new() -> impl PinInit<Self> { ... }
    }

    impl Foo {
        fn new() -> impl PinInit<Self> {
            pin_init!(Self { bar: Bar::new() })
        }
    }

Then the declarative macro would report:

    error[E0308]: mismatched types
      --> tests/ui/compile-fail/init/colon_instead_of_arrow.rs:21:9
       |
    14 |     fn new() -> impl PinInit<Self> {
       |                 ------------------ the found opaque type
    ...
    21 |         pin_init!(Self { bar: Bar::new() })
       |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
       |         |
       |         expected `Bar`, found opaque type
       |         arguments to this function are incorrect
       |
       = note:   expected struct `Bar`
               found opaque type `impl pin_init::PinInit<Bar>`
    note: function defined here
      --> $RUST/core/src/ptr/mod.rs
       |
       | pub const unsafe fn write<T>(dst: *mut T, src: T) {
       |                     ^^^^^
       = note: this error originates in the macro `$crate::__init_internal` which comes from the expansion of the macro `pin_init` (in Nightly builds, run with -Z macro-backtrace for more info)

And the new error is:

    error[E0308]: mismatched types
      --> tests/ui/compile-fail/init/colon_instead_of_arrow.rs:21:31
       |
    14 |     fn new() -> impl PinInit<Self> {
       |                 ------------------ the found opaque type
    ...
    21 |         pin_init!(Self { bar: Bar::new() })
       |                          ---  ^^^^^^^^^^ expected `Bar`, found opaque type
       |                          |
       |                          arguments to this function are incorrect
       |
       = note:   expected struct `Bar`
               found opaque type `impl pin_init::PinInit<Bar>`
    note: function defined here
      --> $RUST/core/src/ptr/mod.rs
       |
       | pub const unsafe fn write<T>(dst: *mut T, src: T) {
       |                     ^^^^^

Importantly, this error gives much more accurate span locations,
pointing to the offending field, rather than the entire macro
invocation.

Tested-by: Andreas Hindborg <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Benno Lossin <[email protected]>
2026-01-17 10:51:42 +01:00
Benno Lossin 560f6d13c3 rust: pin-init: rewrite #[pin_data] using syn
Rewrite the attribute macro `#[pin_data]` using `syn`. No functional
changes intended aside from improved error messages on syntactic and
semantical errors. For example if one forgets a comma at the end of a
field:

    #[pin_data]
    struct Foo {
        a: Box<Foo>
        b: Box<Foo>
    }

The declarative macro reports the following errors:

    error: expected `,`, or `}`, found `b`
     --> tests/ui/compile-fail/pin_data/missing_comma.rs:5:16
      |
    5 |     a: Box<Foo>
      |                ^ help: try adding a comma: `,`

    error: recursion limit reached while expanding `$crate::__pin_data!`
     --> tests/ui/compile-fail/pin_data/missing_comma.rs:3:1
      |
    3 | #[pin_data]
      | ^^^^^^^^^^^
      |
      = help: consider increasing the recursion limit by adding a `#![recursion_limit = "256"]` attribute to your crate (`$CRATE`)
      = note: this error originates in the macro `$crate::__pin_data` which comes from the expansion of the attribute macro `pin_data` (in Nightly builds, run with -Z macro-backtrace for more info)

The new `syn` version reports:

    error: expected `,`, or `}`, found `b`
     --> tests/ui/compile-fail/pin_data/missing_comma.rs:5:16
      |
    5 |     a: Box<Foo>
      |                ^ help: try adding a comma: `,`

    error: expected `,`
     --> tests/ui/compile-fail/pin_data/missing_comma.rs:6:5
      |
    6 |     b: Box<Foo>
      |     ^

Tested-by: Andreas Hindborg <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Benno Lossin <[email protected]>
2026-01-17 10:51:42 +01:00
Benno Lossin a92f5fd292 rust: pin-init: rewrite the #[pinned_drop] attribute macro using syn
Rewrite the attribute macro for implementing `PinnedDrop` using `syn`.
Otherwise no functional changes intended aside from improved error
messages on syntactic and semantical errors. For example:

When missing the `drop` function in the implementation, the old error
was:

    error: no rules expected `)`
     --> tests/ui/compile-fail/pinned_drop/no_fn.rs:6:1
      |
    6 | #[pinned_drop]
      | ^^^^^^^^^^^^^^ no rules expected this token in macro call
      |
    note: while trying to match keyword `fn`
     --> src/macros.rs
      |
      |             fn drop($($sig:tt)*) {
      |             ^^
      = note: this error originates in the attribute macro `pinned_drop` (in Nightly builds, run with -Z macro-backtrace for more info)

And the new one is:

    error[E0046]: not all trait items implemented, missing: `drop`
     --> tests/ui/compile-fail/pinned_drop/no_fn.rs:7:1
      |
    7 | impl PinnedDrop for Foo {}
      | ^^^^^^^^^^^^^^^^^^^^^^^ missing `drop` in implementation
      |
      = help: implement the missing item: `fn drop(self: Pin<&mut Self>, _: OnlyCallFromDrop) { todo!() }`

Tested-by: Andreas Hindborg <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Benno Lossin <[email protected]>
2026-01-17 10:51:42 +01:00
Benno Lossin 50426bde15 rust: pin-init: rewrite derive(Zeroable) and derive(MaybeZeroable) using syn
Rewrite the two derive macros for `Zeroable` using `syn`. One positive
side effect of this change is that tuple structs are now supported by
them. Additionally, syntax errors and the error emitted when trying to
use one of the derive macros on an `enum` are improved. Otherwise no
functional changes intended.

For example:

    #[derive(Zeroable)]
    enum Num {
        A(u32),
        B(i32),
    }

Produced this error before this commit:

    error: no rules expected keyword `enum`
     --> tests/ui/compile-fail/zeroable/enum.rs:5:1
      |
    5 | enum Num {
      | ^^^^ no rules expected this token in macro call
      |
    note: while trying to match keyword `struct`
     --> src/macros.rs
      |
      |             $vis:vis struct $name:ident
      |                      ^^^^^^

Now the error is:

    error: cannot derive `Zeroable` for an enum
     --> tests/ui/compile-fail/zeroable/enum.rs:5:1
      |
    5 | enum Num {
      | ^^^^

    error: cannot derive `Zeroable` for an enum

Tested-by: Andreas Hindborg <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Benno Lossin <[email protected]>
2026-01-17 10:51:42 +01:00
Benno Lossin 901f1d73d2 rust: pin-init: allow the crate to refer to itself as pin-init in doc tests
The `syn` approach requires use of `::pin_init::...` instead of the
`$crate::...` construct available to declarative macros. To be able to
use the `pin_init` crate from itself (which includes doc tests), we have
to declare it as such.

Reviewed-by: Gary Guo <[email protected]>
Tested-by: Andreas Hindborg <[email protected]>
Signed-off-by: Benno Lossin <[email protected]>
2026-01-17 10:49:31 +01:00
Benno Lossin 61d62ab08f rust: pin-init: remove try_ versions of the initializer macros
The `try_[pin_]init!` versions of the initializer macros are
superfluous. Instead of forcing the user to always write an error in
`try_[pin_]init!` and not allowing one in `[pin_]init!`, combine them
into `[pin_]init!` that defaults the error to
`core::convert::Infallible`, but also allows to specify a custom one.

Projects using pin-init still can provide their own defaulting
initializers using the `try_` prefix by using the `#[default_error]`
attribute added in a future patch.

[ Adjust the definition of the kernel's version of the `try_`
  initializer macros - Benno]

Reviewed-by: Gary Guo <[email protected]>
Tested-by: Andreas Hindborg <[email protected]>
Signed-off-by: Benno Lossin <[email protected]>
2026-01-17 10:49:31 +01:00
Linus Torvalds 416f99c3b1 Merge tag 'driver-core-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core
Pull driver core updates from Danilo Krummrich:
 "Arch Topology:
   - Move parse_acpi_topology() from arm64 to common code for reuse in
     RISC-V

  CPU:
   - Expose housekeeping CPUs through /sys/devices/system/cpu/housekeeping
   - Print a newline (or 0x0A) instead of '(null)' reading
     /sys/devices/system/cpu/nohz_full when nohz_full= is not set

  debugfs
   - Remove (broken) 'no-mount' mode
   - Remove redundant access mode checks in debugfs_get_tree() and
     debugfs_create_*() functions

  Devres:
   - Remove unused devm_free_percpu() helper
   - Move devm_alloc_percpu() from device.h to devres.h

  Firmware Loader:
   - Replace simple_strtol() with kstrtoint()
   - Do not call cancel_store() when no upload is in progress

  kernfs:
   - Increase struct super_block::maxbytes to MAX_LFS_FILESIZE
   - Fix a missing unwind path in __kernfs_new_node()

  Misc:
   - Increase the name size in struct auxiliary_device_id to 40
     characters
   - Replace system_unbound_wq with system_dfl_wq and add WQ_PERCPU to
     alloc_workqueue()

  Platform:
   - Replace ERR_PTR() with IOMEM_ERR_PTR() in platform ioremap
     functions

  Rust:
   - Auxiliary:
      - Unregister auxiliary device on parent device unbind
      - Move parent() to impl Device; implement device context aware
        parent() for Device<Bound>
      - Illustrate how to safely obtain a driver's device private data
        when calling from an auxiliary driver into the parant device
        driver

   - DebugFs:
      - Implement support for binary large objects

   - Device:
      - Let probe() return the driver's device private data as pinned
        initializer, i.e. impl PinInit<Self, Error>
      - Implement safe accessor for a driver's device private data for
        Device<Bound> (returned reference can't out-live driver binding
        and guarantees the correct private data type)
      - Implement AsBusDevice trait, to be used by class device
        abstractions to derive the bus device type of the parent device

   - DMA:
      - Store raw pointer of allocation as NonNull
      - Use start_ptr() and start_ptr_mut() to inherit correct
        mutability of self

   - FS:
      - Add file::Offset type alias

   - I2C:
      - Add abstractions for I2C device / driver infrastructure
      - Implement abstractions for manual I2C device registrations

   - I/O:
      - Use "kernel vertical" style for imports
      - Define ResourceSize as resource_size_t
      - Move ResourceSize to top-level I/O module
      - Add type alias for phys_addr_t
      - Implement Rust version of read_poll_timeout_atomic()

   - PCI:
      - Use "kernel vertical" style for imports
      - Move I/O and IRQ infrastructure to separate files
      - Add support for PCI interrupt vectors
      - Implement TryInto<IrqRequest<'a>> for IrqVector<'a> to convert
        an IrqVector bound to specific pci::Device into an IrqRequest
        bound to the same pci::Device's parent Device
      - Leverage pin_init_scope() to get rid of redundant Result in IRQ
        methods

   - PinInit:
      - Add {pin_}init_scope() to execute code before creating an
        initializer

   - Platform:
      - Leverage pin_init_scope() to get rid of redundant Result in IRQ
        methods

   - Timekeeping:
      - Implement abstraction of udelay()

   - Uaccess:
      - Implement read_slice_partial() and read_slice_file() for
        UserSliceReader
      - Implement write_slice_partial() and write_slice_file() for
        UserSliceWriter

  sysfs:
   - Prepare the constification of struct attribute"

* tag 'driver-core-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: (75 commits)
  rust: pci: fix build failure when CONFIG_PCI_MSI is disabled
  debugfs: Fix default access mode config check
  debugfs: Remove broken no-mount mode
  debugfs: Remove redundant access mode checks
  driver core: Check drivers_autoprobe for all added devices
  driver core: WQ_PERCPU added to alloc_workqueue users
  driver core: replace use of system_unbound_wq with system_dfl_wq
  tick/nohz: Expose housekeeping CPUs in sysfs
  tick/nohz: avoid showing '(null)' if nohz_full= not set
  sysfs/cpu: Use DEVICE_ATTR_RO for nohz_full attribute
  kernfs: fix memory leak of kernfs_iattrs in __kernfs_new_node
  fs/kernfs: raise sb->maxbytes to MAX_LFS_FILESIZE
  mod_devicetable: Bump auxiliary_device_id name size
  sysfs: simplify attribute definition macros
  samples/kobject: constify 'struct foo_attribute'
  samples/kobject: add is_visible() callback to attribute group
  sysfs: attribute_group: enable const variants of is_visible()
  sysfs: introduce __SYSFS_FUNCTION_ALTERNATIVE()
  sysfs: transparently handle const pointers in ATTRIBUTE_GROUPS()
  sysfs: attribute_group: allow registration of const attribute
  ...
2025-12-05 21:29:02 -08:00
Benno Lossin 53870c679e rust: pin-init: fix broken rust doc link
Rust 1.92.0 warns when building the documentation that [`PinnedDrop`] is
an invalid reference. This is correct and it's weird that it didn't warn
before, so fix the link.

[ The reason is that it is hidden -- I had asked about that in the
  upstream PR that changed the behavior because I wasn't sure it was
  intentional (and thus whether we needed to fix this and other cases):

      https://github.com/rust-lang/rust/pull/147153#issuecomment-3395484636

  It turns out it was not, and it has been fixed for 1.92.0's upcoming
  release thanks to Guillaume and León. So we do not strictly need
  this patch and the other changes anymore:

      https://github.com/rust-lang/rust/pull/147809

  However, checking hidden/private items or, even better, a runtime
  toggle to be able to see those on the fly, is something that I think
  would be quite nice so I have had it in our usual lists for a while.
  Guillaume is open to the idea and perhaps experimenting with an
  implementation on our side first -- he asked me to open issues
  upstream:

      https://github.com/rust-lang/rust/issues/149105
      https://github.com/rust-lang/rust/issues/149106

    - Miguel ]

Signed-off-by: Benno Lossin <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>
2025-11-19 22:18:33 +01:00
Benno Lossin fc2b38de4c add [pin_]init_scope to execute code before creating an initializer
In more complex cases, initializers need to run arbitrary code before
assigning initializers to fields. While this is possible using the
underscore codeblock feature (`_: {}`), values returned by such
functions cannot be used from later field initializers.

The two new functions `[pin_]init_scope` allow users to first run some
fallible code and then return an initializer which the function turns
into a single initializer. This permits using the same value multiple
times by different fields.

Reviewed-by: Gary Guo <[email protected]>
Reviewed-by: Danilo Krummrich <[email protected]>
Signed-off-by: Benno Lossin <[email protected]>
Reviewed-by: Alice Ryhl <[email protected]>
[ Fix typo in commit message: s/functinos/functions/. - Danilo ]
Signed-off-by: Danilo Krummrich <[email protected]>
2025-10-21 00:40:12 +02:00
Benno Lossin 42415d163e rust: pin-init: add references to previously initialized fields
After initializing a field in an initializer macro, create a variable
holding a reference that points at that field. The type is either
`Pin<&mut T>` or `&mut T` depending on the field's structural pinning
kind.

[ Applied fixes to devres and rust_driver_pci sample - Benno]
Reviewed-by: Danilo Krummrich <[email protected]>
Signed-off-by: Benno Lossin <[email protected]>
2025-09-11 23:30:02 +02:00
Benno Lossin 1fa516794f rust: pin-init: add code blocks to [try_][pin_]init! macros
Allow writing `_: { /* any number of statements */ }` in initializers to
run arbitrary code during initialization.

    try_init!(MyStruct {
        _: {
            if check_something() {
                return Err(MyError);
            }
        },
        foo: Foo::new(val),
        _: {
            println!("successfully initialized `MyStruct`");
        },
    })

Tested-by: Alexandre Courbot <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Reviewed-by: Alice Ryhl <[email protected]>
Tested-by: Danilo Krummrich <[email protected]>
Reviewed-by: Danilo Krummrich <[email protected]>
Signed-off-by: Benno Lossin <[email protected]>
2025-09-11 23:26:44 +02:00
Benno Lossin 619db96daf rust: pin-init: add pin projections to #[pin_data]
Make the `#[pin_data]` macro generate a `*Projection` struct that holds
either `Pin<&mut Field>` or `&mut Field` for every field of the original
struct. Which version is chosen depends on weather there is a `#[pin]`
or not respectively. Access to this projected version is enabled through
generating `fn project(self: Pin<&mut Self>) -> SelfProjection<'_>`.

[ Adapt workqueue to use the new projection instead of its own, custom
  one - Benno ]

Reviewed-by: Gary Guo <[email protected]>
Reviewed-by: Boqun Feng <[email protected]>
Signed-off-by: Benno Lossin <[email protected]>
2025-09-11 23:26:20 +02:00
Benno Lossin d49c56368c rust: pin-init: rename project -> project_this in doctest
The next commit makes the `#[pin_data]` attribute generate a `project`
function that would collide with any existing ones.

Signed-off-by: Benno Lossin <[email protected]>
2025-09-11 23:26:11 +02:00
Miguel Ojeda e8fa0481ea Merge tag 'pin-init-v6.17' of https://github.com/Rust-for-Linux/linux into rust-next
Pull pin-init updates from Benno Lossin:
 "Added:

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

   - 'Zeroable::init_zeroed()' delegating to 'init_zeroed()'.

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

   - Implement 'Zeroable' for 'Option<&T>' and 'Option<&mut T>'.

   - Implement 'Zeroable' 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:

   - More CI improvements to deny warnings, use '--all-targets'. Also
     check the synchronization status of the two '-next' branches in
     upstream and the kernel."

Acked-by: Andreas Hindborg <[email protected]>

* tag 'pin-init-v6.17' of https://github.com/Rust-for-Linux/linux:
  rust: pin-init: examples, tests: use `ignore` instead of conditionally compiling tests
  rust: init: remove doctest's `Error::from_errno` workaround
  rust: init: re-enable doctests
  rust: pin-init: implement `ZeroableOption` for function pointers with up to 20 arguments
  rust: pin-init: change `impl Zeroable for Option<NonNull<T>>` to `ZeroableOption for NonNull<T>`
  rust: pin-init: implement `ZeroableOption` for `&T` and `&mut T`
  rust: pin-init: add `zeroed()` & `Zeroable::zeroed()` functions
  rust: pin-init: add `Zeroable::init_zeroed`
  rust: pin-init: rename `zeroed` to `init_zeroed`
  rust: pin-init: feature-gate the `stack_init_reuse` test on the `std` feature
  rust: pin-init: examples: pthread_mutex: disable the main test for miri
  rust: pin-init: examples, tests: add conditional compilation in order to compile under any feature combination
  rust: pin-init: change blanket impls for `[Pin]Init` and add one for `Result<T, E>`
  rust: pin-init: improve safety documentation for `impl<T> [Pin]Init<T> for T`
2025-07-13 23:05:14 +02:00
Viresh Kumar b6985083be rust: Use consistent "# Examples" heading style in rustdoc
Use a consistent `# Examples` heading in rustdoc across the codebase.

Some modules previously used `## Examples` (even when they should be
available as top-level headers), while others used `# Example`, which
deviates from the preferred `# Examples` style.

Suggested-by: Miguel Ojeda <[email protected]>
Signed-off-by: Viresh Kumar <[email protected]>
Acked-by: Benno Lossin <[email protected]>
Link: https://lore.kernel.org/r/ddd5ce0ac20c99a72a4f1e4322d3de3911056922.1749545815.git.viresh.kumar@linaro.org
Signed-off-by: Miguel Ojeda <[email protected]>
2025-06-24 01:02:30 +02:00
Benno Lossin ec87ec35ca rust: pin-init: implement ZeroableOption for function pointers with up to 20 arguments
`Option<[unsafe] [extern "abi"] fn(...args...) -> ret>` is documented
[1] to also have the `None` variant equal all zeroes.

Link: https://doc.rust-lang.org/stable/std/option/index.html#representation [1]
Link: https://github.com/Rust-for-Linux/pin-init/pull/56/commits/b6c1ab4fb3699765f81ae512ecac5a2f032d8d51
Link: https://lore.kernel.org/all/[email protected]
Signed-off-by: Benno Lossin <[email protected]>
2025-06-11 21:13:57 +02:00
Benno Lossin 9f47353870 rust: pin-init: change impl Zeroable for Option<NonNull<T>> to ZeroableOption for NonNull<T>
This brings it in line with references. It too is listed in [1].

Link: https://doc.rust-lang.org/stable/std/option/index.html#representation
Link: https://github.com/Rust-for-Linux/pin-init/pull/56/commits/8e52bf56ddc2190ce901d2f7c008ab8a64f653a9
Link: https://lore.kernel.org/all/[email protected]
Signed-off-by: Benno Lossin <[email protected]>
2025-06-11 21:13:56 +02:00
Benno Lossin e93a238605 rust: pin-init: implement ZeroableOption for &T and &mut T
`Option<&T>` and `Option<&mut T>` are documented [1] to have the `None`
variant be all zeroes.

Link: https://doc.rust-lang.org/stable/std/option/index.html#representation [1]
Link: https://github.com/Rust-for-Linux/pin-init/pull/56/commits/5ef1638c79e019d3dc0c62db5905601644c2e60a
Link: https://lore.kernel.org/all/[email protected]
Signed-off-by: Benno Lossin <[email protected]>
2025-06-11 21:13:56 +02:00