Re: [PATCH 3/4] rust: devres: get rid of Devres' inner Arc

[Danilo Krummrich <dakr@kernel.org>]

On Sun, Jun 22, 2025 at 09:05:51AM +0200, Benno Lossin wrote:
> On Thu Jun 12, 2025 at 4:51 PM CEST, Danilo Krummrich wrote:
> > +    fn remove_action(&self) -> bool {
> > +        // SAFETY:
> > +        // - `self.dev` is a valid `Device`,
> > +        // - the `action` and `data` pointers are the exact same ones as given to devm_add_action()
> > +        //   previously,
> > +        // - `self` is always valid, even if the action has been released already.
> > +        (unsafe {
> > +            bindings::devm_remove_action_nowarn(
> > +                self.dev.as_raw(),
> > +                Some(self.callback),
> > +                self.as_ptr().cast_mut().cast(),
> > +            )
> > +        } == 0)
> 
> I don't think the parenthesis are required?

At least the compiler doesn't seem to be happy about removing them:

error: expected expression, found `==`
   --> rust/kernel/devres.rs:199:11
    |
199 |         } == 0
    |           ^^ expected expression

error[E0308]: mismatched types
   --> rust/kernel/devres.rs:194:13
    |
194 | /             bindings::devm_remove_action_nowarn(
195 | |                 self.dev.as_raw(),
196 | |                 Some(self.callback),
197 | |                 self.inner().as_ptr().cast_mut().cast(),
198 | |             )
    | |             ^- help: consider using a semicolon here: `;`
    | |_____________|
    |               expected `()`, found `i32`

error: aborting due to 2 previous errors