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Date:   Sat, 21 Oct 2023 14:45:09 +0200
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Subject: Re: [PATCH v2] rust: macros: improve `#[vtable]` documentation
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To:     Benno Lossin <benno.lossin@proton.me>
Cc:     Boqun Feng <boqun.feng@gmail.com>, Gary Guo <gary@garyguo.net>,
        =?UTF-8?Q?Bj=C3=B6rn_Roy_Baron?= <bjorn3_gh@protonmail.com>,
        Alice Ryhl <aliceryhl@google.com>,
        Andreas Hindborg <nmi@metaspace.dk>,
        rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org,
        Miguel Ojeda <ojeda@kernel.org>,
        Wedson Almeida Filho <wedsonaf@gmail.com>,
        Alex Gaynor <alex.gaynor@gmail.com>
References: <20231019171540.259173-1-benno.lossin@proton.me>
From:   Alice Ryhl <alice@ryhl.io>
In-Reply-To: <20231019171540.259173-1-benno.lossin@proton.me>
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On 10/19/23 19:15, Benno Lossin wrote:
> Traits marked with `#[vtable]` need to provide default implementations
> for optional functions. The C side represents these with `NULL` in the
> vtable, so the default functions are never actually called. We do not
> want to replicate the default behavior from C in Rust, because that is
> not maintainable. Therefore we should use `build_error` in those default
> implementations. The error message for that is provided at
> `kernel::error::VTABLE_DEFAULT_ERROR`.
> 
> Signed-off-by: Benno Lossin <benno.lossin@proton.me>

Reviewed-by: Alice Ryhl <aliceryhl@google.com>

There is a minor nit below, and in reviews sent by others, but overall 
this looks fine to me.

>   /// # Examples
>   ///
>   /// ```ignore
> +/// # use kernel::error::VTABLE_DEFAULT_ERROR;
>   /// use kernel::prelude::*;
I probably wouldn't hide the import of VTABLE_DEFAULT_ERROR from this 
example.