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Message-ID: <66994d628df70a5ff535908efc16568d3a5a4c80.camel@sipsolutions.net>
Subject: Re: [RFC PATCH v3 0/2] rust: crates in other kernel directories
From: Johannes Berg <johannes@sipsolutions.net>
To: Martin Rodriguez Reboredo <yakoyoku@gmail.com>, Miguel Ojeda
 <ojeda@kernel.org>, Alex Gaynor <alex.gaynor@gmail.com>, Wedson Almeida
 Filho <wedsonaf@gmail.com>, Boqun Feng <boqun.feng@gmail.com>, Gary Guo
 <gary@garyguo.net>, =?ISO-8859-1?Q?Bj=F6rn?= Roy Baron
 <bjorn3_gh@protonmail.com>, Benno Lossin <benno.lossin@proton.me>, Andreas
 Hindborg <a.hindborg@samsung.com>, Alice Ryhl <aliceryhl@google.com>
Cc: linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, 
	rust-for-linux@vger.kernel.org
Date: Fri, 15 Mar 2024 14:44:16 +0100
In-Reply-To: <20231104211213.225891-1-yakoyoku@gmail.com>
References: <20231104211213.225891-1-yakoyoku@gmail.com>
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Hi,

So I realize this is an old patch, but I didn't find another version,
and discussions seemed ongoing at least a month ago. I also came across
it pretty randomly.

Anyway, question:

> If you want to use a crate with your Rust module just add a `rust-libs`
> variable in your Makefile with a value of the relative directory of
> said crate plus its name, e.g.
>=20
>     # Link with the foo crate
>     rust-libs +=3D ../path/to/foo

Should this perhaps be relative to the kernel's root dir instead?=C2=A0

If I'm reading this correctly, then a hypothetical rust wireless driver
that lives in

  drivers/net/wireless/<vendor>/<name>/

using some wireless rust infrastructure would probably end up with
something like

  rust-libs +=3D ../../../../../net/mac80211/rust/

or whatever, which seems rather odd vs.

  rust-libs +=3D net/mac80211/rust/

Seems to me that chances are that subsystems/drivers that have rust
infrastructure will not necessarily have them close to each other, like
in this example?

You have this in the sample too:

+rust-libs					:=3D ../../drivers/usb/core/usb

but it's less pronounced since it's just samples/rust/ :)

johannes