Re: [PATCH 0/4] Re-export Zeroable and zeroed() from ffi module

From: Alice Ryhl

Date: Mon Jan 26 2026 - 08:25:49 EST


On Mon, Jan 26, 2026 at 01:15:53PM +0000, Gary Guo wrote:
> On Mon Jan 26, 2026 at 1:05 PM GMT, Alice Ryhl wrote:
> > Currently, the Zeroable trait is defined by pin-init because pin-init
> > happens to use the trait. However, zeroed types are useful for many
> > purposes other than pin-init. Also, we wish to implement Zeroable for
> > types generated by bindgen. For both of these reasons, re-export
> > Zeroable from the ffi crate, which is a already dependency of the crates
> > with bindgen output.
>
> I don't see a benefit of re-exporting these from the `ffi` crate? Especially
> that we re-export `ffi` crate from kernel crate anyway, and `Zeroable` is
> already in the kernel prelude.
>
> We already derive `Zeroable` for bindgen via `MaybeZeroable` derive in
> rust/bindgen_parameters.

I can't find the convo now, but this change is on my list from when we
discussed also implementing FromBytes / IntoBytes for the bindings
types. To do that, we need to move our FromBytes / IntoBytes traits
somewhere that bindings/uapi can access, and we agreed that the ffi
crate was a good place for it.

And then for consistency, also reexport Zeroable from the same location.

Alice