Re: [PATCH] rust: init: fix `Zeroable` implementation for `Option<NonNull<T>>` and `Option<KBox<T>>`

On Wed Mar 5, 2025 at 2:29 PM CET, Benno Lossin wrote:

According to [1], `NonNull<T>` and `#[repr(transparent)]` wrapper types such as our custom `KBox<T>` have the null pointer optimization only if `T: Sized`. Thus remove the `Zeroable` implementation for the unsized case.

Link: https://doc.rust-lang.org/stable/std/option/index.html#representation [1] Cc: stable@vger.kernel.org # v6.12+ (a custom patch will be needed for 6.6.y) Fixes: 38cde0bd7b67 ("rust: init: add `Zeroable` trait and `init::zeroed` function") Signed-off-by: Benno Lossin benno.lossin@proton.me

Forgot to add this:

Reported-by: Alice Ryhl aliceryhl@google.com

--- Cheers, Benno