# Meeting 2023-11-01
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## Critical
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* [x] No open meeting this rc-1 (since it conflicts with LPC)
* [x] More reschedule due to daylight saving end?

## Status Reports
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### Binder RFC was sent

https://lore.kernel.org/rust-for-linux/[e-mail]/

## Discussion Questions
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### `Opaque` is not enough

I just noticed this issue after the discussion about the data races on Tomo's patches.
`&mut T` asserts uniqueness even for `&mut UnsafeCell<T>`. There is [this discussion](https://rust-lang.zulipchat.com/#narrow/stream/136281-t-opsem/topic/UnsafeCellMut/near/308124014) on zulip, but I remember vaguely to have discussed it elsewhere as well.

The problem is that `UnsafeCell` has a **safe** function [`get_mut(&mut self) -> &mut T`](https://doc.rust-lang.org/core/cell/struct.UnsafeCell.html#method.get_mut) that would allow one to violate the intended guarantees of `&mut Opaque<T>`.

Question: What do we do about this?

Alice: `Opaque` is `!Unpin`, which means that `&mut T` does not assert uniqueness.

Benno: *facepalm* I totally forgot about this. Do we have this documented somewhere?

I think if not, then I will send another docs improvements patch :)

Here is the patch that made it `!Unpin`: https://lore.kernel.org/rust-for-linux/[e-mail]/ we did not talk about that at all.
So theoretically we had this issue before we changed this. Is this patch also in the stable tree?

See also: https://github.com/rust-lang/rfcs/pull/3467

### Modules as a config option

## Miscellaneous
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