Re: [PATCH v1] rust: console: add abstraction for kernel console drivers

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Fri, Feb 27, 2026 at 01:53:56PM -0800, Matthew Wood wrote:
> Add a safe Rust abstraction for the kernel's `struct console`,
> enabling console drivers to be implemented in Rust that provides:
> 
>   - `ConsoleOps` trait with a required `write` callback and an
>     optional `setup` callback, mirroring the C console_operations
>     interface. The trait requires `Send + Sync` to reflect that
>     console write may be called from any context including IRQ.
> 
>   - `Console<T>` struct that wraps `struct console` using pin-init
>     and `Opaque<T>`, with automatic unregistration via `PinnedDrop`.
>     Registration is performed through a pin-initializer returned by
>     `Console::register()`, which uses `pin_chain` to set the data
>     pointer and call `register_console()` after the struct is pinned.
> 
>   - `ConsoleOpsAdapter<T>` that provides the extern "C" callbacks
>     bridging from the kernel's function pointers to the Rust trait
>     methods. The `#[vtable]` attribute on `ConsoleOps` enables
>     compile-time detection of whether `setup` is implemented via
>     `T::HAS_SETUP`.
> 
>   - Console flag constants re-exported from the C `enum cons_flags`.
> 
> C helper functions are added for `register_console()`,
> `unregister_console()`, and `console_is_registered()` as these are
> either inlines or macros that cannot be called directly from Rust
> through bindgen.
> 
> This abstraction is a dependency for a Rust netconsole implementation
> I am working on.

I'd prefer to see it then, with the user, before even reviewing this
one, sorry.  That way we "know" it at least works for you.

thanks,

greg k-h