From 63b27f4a0074bc6ef987a44ee9ad8bf960b568c2 Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Tue, 9 Jul 2024 18:06:01 +0200 Subject: rust: start supporting several compiler versions It is time to start supporting several Rust compiler versions and thus establish a minimum Rust version. We may still want to upgrade the minimum sometimes in the beginning since there may be important features coming into the language that improve how we write code (e.g. field projections), which may or may not make sense to support conditionally. We will start with a window of two stable releases, and widen it over time. Thus this patch does not move the current minimum (1.78.0), but instead adds support for the recently released 1.79.0. This should already be enough for kernel developers in distributions that provide recent Rust compiler versions routinely, such as Arch Linux, Debian Unstable (outside the freeze period), Fedora Linux, Gentoo Linux (especially the testing channel), Nix (unstable) and openSUSE Tumbleweed. See the documentation patch about it later in this series. In addition, Rust for Linux is now being built-tested in Rust's pre-merge CI [1]. That is, every change that is attempting to land into the Rust compiler is tested against the kernel, and it is merged only if it passes -- thanks to the Rust project for that! Thus, with the pre-merge CI in place, both projects hope to avoid unintentional changes to Rust that break the kernel. This means that, in general, apart from intentional changes on their side (that we will need to workaround conditionally on our side), the upcoming Rust compiler versions should generally work. For instance, currently, the beta (1.80.0) and nightly (1.81.0) branches work as well. Of course, the Rust for Linux CI job in the Rust toolchain may still need to be temporarily disabled for different reasons, but the intention is to help bring Rust for Linux into stable Rust. Link: https://github.com/rust-lang/rust/pull/125209 [1] Reviewed-by: Finn Behrens Tested-by: Benno Lossin Tested-by: Andreas Hindborg Link: https://lore.kernel.org/r/20240709160615.998336-7-ojeda@kernel.org Signed-off-by: Miguel Ojeda --- Documentation/process/changes.rst | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'Documentation/process') diff --git a/Documentation/process/changes.rst b/Documentation/process/changes.rst index 5685d7bfe4d0..0d0b7120792b 100644 --- a/Documentation/process/changes.rst +++ b/Documentation/process/changes.rst @@ -88,9 +88,7 @@ docs on :ref:`Building Linux with Clang/LLVM `. Rust (optional) --------------- -A particular version of the Rust toolchain is required. Newer versions may or -may not work because the kernel depends on some unstable Rust features, for -the moment. +A recent version of the Rust compiler is required. Each Rust toolchain comes with several "components", some of which are required (like ``rustc``) and some that are optional. The ``rust-src`` component (which -- cgit v1.3.1 From b1263411112305acf2af728728591465becb45b0 Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Tue, 9 Jul 2024 18:06:08 +0200 Subject: docs: rust: quick-start: add section on Linux distributions MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Now that we are starting to support several Rust compiler and `bindgen` versions, there is a good chance some Linux distributions work out of the box. Thus, provide some instructions on how to set the toolchain up for a few major Linux distributions. This simplifies the setup users need to build the kernel. In addition, add an introduction to the document so that it is easier to understand its structure and move the LLVM+Rust kernel.org toolchains paragraph there (removing "depending on the Linux version"). We may want to reorganize the document or split it in the future, but I wanted to focus this commit on the new information added about each particular distribution. Finally, remove the `rustup`'s components mention in `changes.rst` since users do not need it if they install the toolchain via the distributions (and anyway it was too detailed for that main document). Cc: Jan Alexander Steffens Cc: Johannes Löthberg Cc: Fabian Grünbichler Cc: Josh Stone Cc: Randy Barlow Cc: Anna (navi) Figueiredo Gomes Cc: Matoro Mahri Cc: Ryan Scheel Cc: figsoda Cc: Jörg Thalheim Cc: Theodore Ni <43ngvg@masqt.com> Cc: Winter Cc: William Brown Cc: Xiaoguang Wang Cc: Andrea Righi Cc: Zixing Liu Cc: Nathan Chancellor Tested-by: Benno Lossin Tested-by: Andreas Hindborg Link: https://lore.kernel.org/r/20240709160615.998336-14-ojeda@kernel.org Signed-off-by: Miguel Ojeda --- Documentation/process/changes.rst | 5 -- Documentation/rust/quick-start.rst | 93 +++++++++++++++++++++++++++++++++----- 2 files changed, 81 insertions(+), 17 deletions(-) (limited to 'Documentation/process') diff --git a/Documentation/process/changes.rst b/Documentation/process/changes.rst index 0d0b7120792b..0ce96ae2588c 100644 --- a/Documentation/process/changes.rst +++ b/Documentation/process/changes.rst @@ -90,11 +90,6 @@ Rust (optional) A recent version of the Rust compiler is required. -Each Rust toolchain comes with several "components", some of which are required -(like ``rustc``) and some that are optional. The ``rust-src`` component (which -is optional) needs to be installed to build the kernel. Other components are -useful for developing. - Please see Documentation/rust/quick-start.rst for instructions on how to satisfy the build requirements of Rust support. In particular, the ``Makefile`` target ``rustavailable`` is useful to check why the Rust toolchain may not diff --git a/Documentation/rust/quick-start.rst b/Documentation/rust/quick-start.rst index 66cefbab8f9a..d06a36106cd4 100644 --- a/Documentation/rust/quick-start.rst +++ b/Documentation/rust/quick-start.rst @@ -5,24 +5,93 @@ Quick Start This document describes how to get started with kernel development in Rust. +There are a few ways to install a Rust toolchain needed for kernel development. +A simple way is to use the packages from your Linux distribution if they are +suitable -- the first section below explains this approach. An advantage of this +approach is that, typically, the distribution will match the LLVM used by Rust +and Clang. + +Another way is using the prebuilt stable versions of LLVM+Rust provided on +`kernel.org `_. These are the same slim +and fast LLVM toolchains from :ref:`Getting LLVM ` with versions +of Rust added to them that Rust for Linux supports. Two sets are provided: the +"latest LLVM" and "matching LLVM" (please see the link for more information). + +Alternatively, the next two "Requirements" sections explain each component and +how to install them through ``rustup``, the standalone installers from Rust +and/or building them. + +The rest of the document explains other aspects on how to get started. + + +Distributions +------------- + +Arch Linux +********** + +Arch Linux provides recent Rust releases and thus it should generally work out +of the box, e.g.:: + + pacman -S rust rust-src rust-bindgen + + +Debian +****** + +Debian Unstable (Sid), outside of the freeze period, provides recent Rust +releases and thus it should generally work out of the box, e.g.:: + + apt install rustc rust-src bindgen rustfmt rust-clippy + + +Fedora Linux +************ + +Fedora Linux provides recent Rust releases and thus it should generally work out +of the box, e.g.:: + + dnf install rust rust-src bindgen-cli rustfmt clippy + + +Gentoo Linux +************ + +Gentoo Linux (and especially the testing branch) provides recent Rust releases +and thus it should generally work out of the box, e.g.:: + + USE='rust-src rustfmt clippy' emerge dev-lang/rust dev-util/bindgen + +``LIBCLANG_PATH`` may need to be set. + + +Nix +*** + +Nix (unstable channel) provides recent Rust releases and thus it should +generally work out of the box, e.g.:: + + { pkgs ? import {} }: + pkgs.mkShell { + nativeBuildInputs = with pkgs; [ rustc rust-bindgen rustfmt clippy ]; + RUST_LIB_SRC = "${pkgs.rust.packages.stable.rustPlatform.rustLibSrc}"; + } + + +openSUSE +******** + +openSUSE Slowroll and openSUSE Tumbleweed provide recent Rust releases and thus +they should generally work out of the box, e.g.:: + + zypper install rust rust1.79-src rust-bindgen clang + Requirements: Building ---------------------- This section explains how to fetch the tools needed for building. -Some of these requirements might be available from Linux distributions -under names like ``rustc``, ``rust-src``, ``rust-bindgen``, etc. However, -at the time of writing, they are likely not to be recent enough unless -the distribution tracks the latest releases. - -Prebuilt stable versions of LLVM+Rust are provided on `kernel.org -`_. These are the same slim and fast -LLVM toolchains from :ref:`Getting LLVM ` with versions of Rust -added to them that Rust for Linux supports, depending on the Linux version. Two -sets are provided: the "latest LLVM" and "matching LLVM" (please see the link -for more information). - To easily check whether the requirements are met, the following target can be used:: -- cgit v1.3.1