Re: [PATCH -next v7 1/2] rust: clist: Add support to interface with C linked lists

[Joel Fernandes <joelagnelf@nvidia.com>]

On 2/6/2026 12:13 PM, Danilo Krummrich wrote:
> On Fri Feb 6, 2026 at 5:13 PM CET, Gary Guo wrote:
>> On Fri Feb 6, 2026 at 4:05 PM GMT, Joel Fernandes wrote:
>>>
>>>
>>> On 2/6/2026 10:53 AM, Danilo Krummrich wrote:
>>>> On Fri Feb 6, 2026 at 4:25 PM CET, Gary Guo wrote:
>>>>> On Fri Feb 6, 2026 at 12:41 AM GMT, Joel Fernandes wrote:
>>>>>> diff --git a/drivers/gpu/Kconfig b/drivers/gpu/Kconfig
>>>>>> index 22dd29cd50b5..2c3dec070645 100644
>>>>>> --- a/drivers/gpu/Kconfig
>>>>>> +++ b/drivers/gpu/Kconfig
>>>>>> @@ -1,7 +1,14 @@
>>>>>>  # SPDX-License-Identifier: GPL-2.0
>>>>>>  
>>>>>> +config RUST_CLIST
>>>>>> +	bool
>>>>>> +	depends on RUST
>>>>>> +	help
>>>>>> +	  Rust abstraction for interfacing with C linked lists.
>>>>>
>>>>> I am not sure if we need extra config entry. This is fully generic so shouldn't
>>>>> generate any code unless there is an user.
>>>>
>>>> I also don't think we need a Kconfig for this.
>>>>
>>>> In any case, it shouln't be in drivers/gpu/Kconfig.
>>>
>>> Fair point, I believe I was having trouble compiling this into the kernel crate
>>> without warnings (I believe if !GPU_BUDDY). I'll try to drop it and see if we
>>> can get rid of it.
>>
>> If you run into dead code warnings, I think it is fine to just
>>
>>     #[allow(dead_code, reason = "all users might be cfg-ed out")]
>>
>> the overhead of just let rustc type-checking this module isn't worth the extra
>> Kconfig plumbing, I think.
> 
> You mean because there are pub(crate) in clist.rs? I don't think the Kconfig
> would help with that, nothing prevents people from enabling RUST_CLIST, but none
> of the users.

I think he means add the alloc annotation to suppress deadcode warnings and get
rid of the Kconfig?

> Besides that, once we have the new build system, the users of CList are likely
> in other crates anyways, so I think we should just change things to pub.

I agree with both approaches. Perhaps changing to pub is better to avoid churn
in the future when other crates use it.

-- 
Joel Fernandes