Re: [PATCH v15 3/9] rust: Add missing SAFETY documentation for `ARef` example

[Alice Ryhl <aliceryhl@google.com>]

On Fri, Feb 20, 2026 at 10:52 AM Andreas Hindborg <a.hindborg@kernel.org> wrote:
>
> From: Oliver Mangold <oliver.mangold@pm.me>
>
> SAFETY comment in rustdoc example was just 'TODO'. Fixed.
>
> Signed-off-by: Oliver Mangold <oliver.mangold@pm.me>
> Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
> Co-developed-by: Andreas Hindborg <a.hindborg@kernel.org>
> Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
> ---
>  rust/kernel/sync/aref.rs | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
>
> diff --git a/rust/kernel/sync/aref.rs b/rust/kernel/sync/aref.rs
> index 61caddfd89619..efe16a7fdfa5d 100644
> --- a/rust/kernel/sync/aref.rs
> +++ b/rust/kernel/sync/aref.rs
> @@ -129,12 +129,14 @@ pub unsafe fn from_raw(ptr: NonNull<T>) -> Self {
>      /// # Examples
>      ///
>      /// ```
> -    /// use core::ptr::NonNull;
> -    /// use kernel::sync::aref::{ARef, RefCounted};
> +    /// # use core::ptr::NonNull;
> +    /// # use kernel::sync::aref::{ARef, RefCounted};
>      ///

Either keep the imports visible or delete this empty line. And either
way, it doesn't really fit in this commit.

>      /// struct Empty {}
>      ///
> -    /// # // SAFETY: TODO.
> +    /// // SAFETY: The `RefCounted` implementation for `Empty` does not count references and never
> +    /// // frees the underlying object. Thus we can act as owning an increment on the refcount for
> +    /// // the object that we pass to the newly created `ARef`.
>      /// unsafe impl RefCounted for Empty {
>      ///     fn inc_ref(&self) {}
>      ///     unsafe fn dec_ref(_obj: NonNull<Self>) {}
> @@ -142,7 +144,7 @@ pub unsafe fn from_raw(ptr: NonNull<T>) -> Self {
>      ///
>      /// let mut data = Empty {};
>      /// let ptr = NonNull::<Empty>::new(&mut data).unwrap();
> -    /// # // SAFETY: TODO.
> +    /// // SAFETY: We keep `data` around longer than the `ARef`.
>      /// let data_ref: ARef<Empty> = unsafe { ARef::from_raw(ptr) };
>      /// let raw_ptr: NonNull<Empty> = ARef::into_raw(data_ref);
>      ///
>
> --
> 2.51.2
>
>