Re: [PATCH 0/7] misc device: support device drivers

["Benno Lossin" <lossin@kernel.org>]

On Fri May 30, 2025 at 7:29 PM CEST, Christian Schrefl wrote:
> On 30.05.25 6:37 PM, Christian Schrefl wrote:
>> On 30.05.25 4:24 PM, Danilo Krummrich wrote:
>>> This patch series adds support for device drivers to the misc device
>>> abstraction.
>>>
>>> For design details, please see:
>>>   * patch 5 "rust: miscdevice: properly support device drivers"
>>>   * patch 6 "rust: miscdevice: expose the parent device as &Device<Bound>"
>>>
>>> This patch series depends on the pin-init series from Benno [1] as well as on
>>> the misc device series from Christian [2], with UnsafePinned replaced with
>>> Opaque, as suggested by Alice, since UnsafePinned may still take a while to
>>> land.
>> 
>> If you want I can send out a new version using `Opaque`.
>> 
>> We could also add a type alias like:
>> 
>> type UnsafePinned<T> = Opaque<T>;
>
> I forgot that Opaque doesn't drop, this would not be quite as simple,
> but with a newtype with a `Drop` impl it should be possible.

That's one issue another is that `Opaque` also allows uninitialized
memory and (if the upstream one isn't changed) also modifies the
behavior of shared references. I don't think we should name it
`UnsafePinned` if it doesn't guarantee the same thing as the upstream
one.

---
Cheers,
Benno