Re: [PATCH 6/6] rust: driver: drop device private data post unbind

[Greg KH]

On Mon, Jan 12, 2026 at 03:27:08PM +0100, Danilo Krummrich wrote:
> On Wed Jan 7, 2026 at 3:54 PM CET, Greg KH wrote:
> > I say name it with "rust_" and take out the #ifdef, that makes it
> > simpler/easier to understand.
> 
> diff --git a/drivers/base/dd.c b/drivers/base/dd.c
> index 2d9871503614..bea8da5f8a3a 100644
> --- a/drivers/base/dd.c
> +++ b/drivers/base/dd.c
> @@ -548,10 +548,8 @@ static DEVICE_ATTR_RW(state_synced);
>  static void device_unbind_cleanup(struct device *dev)
>  {
>         devres_release_all(dev);
> -#ifdef CONFIG_RUST
> -       if (dev->driver->p_cb.post_unbind)
> -               dev->driver->p_cb.post_unbind(dev);
> -#endif
> +       if (dev->driver->p_cb.post_unbind_rust)
> +               dev->driver->p_cb.post_unbind_rust(dev);
>         arch_teardown_dma_ops(dev);
>         kfree(dev->dma_range_map);
>         dev->dma_range_map = NULL;
> diff --git a/include/linux/device/driver.h b/include/linux/device/driver.h
> index 51a9ebdd8a2d..bbc67ec513ed 100644
> --- a/include/linux/device/driver.h
> +++ b/include/linux/device/driver.h
> @@ -121,15 +121,13 @@ struct device_driver {
>         void (*coredump) (struct device *dev);
> 
>         struct driver_private *p;
> -#ifdef CONFIG_RUST
>         struct {
>                 /*
>                  * Called after remove() and after all devres entries have been
> -                * processed.
> +                * processed. This is a Rust only callback.
>                  */
> -               void (*post_unbind)(struct device *dev);
> +               void (*post_unbind_rust)(struct device *dev);
>         } p_cb;
> -#endif
>  };
> 
> 
> diff --git a/rust/kernel/driver.rs b/rust/kernel/driver.rs
> index 6e32376d4c7c..26095d7bd0d9 100644
> --- a/rust/kernel/driver.rs
> +++ b/rust/kernel/driver.rs
> @@ -207,7 +207,7 @@ fn callbacks_attach(drv: &Opaque<T::DriverType>) {
>          let base = base.cast::<bindings::device_driver>();
> 
>          // SAFETY: It is safe to set the fields of `struct device_driver` on initialization.
> -        unsafe { (*base).p_cb.post_unbind = Some(Self::post_unbind_callback) };
> +        unsafe { (*base).p_cb.post_unbind_rust = Some(Self::post_unbind_callback) };
>      }
> 
>      /// Creates a new instance of the registration object.

Looks good to me, thanks!