Re: [PATCH v19 5/8] rust: rename `AlwaysRefCounted` to `RefCounted`.

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] Copy-paste error in SAFETY comments for `I2cAdapter` and `I2cClient`.
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commit c7fe859c40ffae9a22f5e5fa80c3b5a426e7197d
Author: Oliver Mangold <oliver.mangold@pm.me>

rust: rename AlwaysRefCounted to RefCounted.

This commit splits the AlwaysRefCounted trait into RefCounted and a new
marker trait AlwaysRefCounted. This prevents the unsound creation of an
ARef<T> from an &Owned<T> when types can be either reference counted or
owned.

> diff --git a/rust/kernel/i2c.rs b/rust/kernel/i2c.rs
> index 624b971ca8b0b..02b2c9220eb11 100644
> --- a/rust/kernel/i2c.rs
> +++ b/rust/kernel/i2c.rs

[ ... ]

> @@ -435,6 +436,9 @@ unsafe fn dec_ref(obj: NonNull<Self>) {
>          unsafe { bindings::i2c_put_adapter(obj.as_ref().as_raw()) }
>      }
>  }
> +// SAFETY: We do not implement `Ownable`, thus it is okay to obtain an `ARef<Device>` from an
> +// `&I2cAdapter`.
> +unsafe impl AlwaysRefCounted for I2cAdapter {}

[Severity: Low]
This isn't a bug, but should this SAFETY comment refer to ARef<I2cAdapter>
instead of ARef<Device>? It appears to be a typo from copying the
Device implementation.

[ ... ]

> @@ -511,6 +515,9 @@ unsafe fn dec_ref(obj: NonNull<Self>) {
>          unsafe { bindings::put_device(&raw mut (*obj.as_ref().as_raw()).dev) }
>      }
>  }
> +// SAFETY: We do not implement `Ownable`, thus it is okay to obtain an `ARef<Device>` from an
> +// `&I2cClient`.
> +unsafe impl AlwaysRefCounted for I2cClient {}

[Severity: Low]
This isn't a bug either, but is ARef<Device> also a typo here? It looks
like it should refer to ARef<I2cClient>.

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Sashiko AI review · https://sashiko.dev/#/patchset/20260626-unique-ref-v19-0-2607ca88dfdf@kernel.org?part=5