config: add rust build configurations

Starting with the upcoming v6.1, mainline Linux has merged the
initial Rust infrastructure so this adds some configs for build
testing it together with some sample modules.

The kernel requires a specific version of rustc, so we add the
rustc-1.62 build environment which derives from clang-15, since
a C compiler is still required to build the kernel.

Obviously GCC can be used as well but for now testing all the
toolchain combinations does not add significant value. In the
future more toolchain combinations can be used as needed.

The official "rustup" toolchain installation method is used as
documented in the upstream kernel and because some distros like
Debian stable might not provide up to date toolchain and crates
to keep up with the mainline kernel.

Only the x86_64 architecture is supported by the kernel for now.

We also add the Rust-for-Linux kernel maintainer trees which
contain additional modules and bindings.

Signed-off-by: Adrian Ratiu <[email protected]>

Author: 10ne1

config/core/build-configs.yaml

@@ -106,6 +106,9 @@ trees:
   rt-stable:
     url: "https://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-stable-rt.git"
 
+  rust-for-linux:
+    url: "https://github.com/Rust-for-Linux/linux.git"
+
   samsung:
     url: "https://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung.git"
 
@@ -225,6 +228,42 @@ fragments:
       - 'CONFIG_PREEMPT_RT=y'
       - 'CONFIG_PREEMPT_RT_FULL=y' # <= v4.19
 
+  rust:
+    path: "kernel/configs/rust.config"
+    configs:
+      - 'CONFIG_RUST=y'
+
+  rust-samples:
+    path: "kernel/configs/rust-samples.config"
+    configs:
+      - 'CONFIG_SAMPLES=y'
+      - 'CONFIG_SAMPLES_RUST=y'
+      - 'CONFIG_SAMPLE_RUST_HOSTPROGS=y'
+      - 'CONFIG_SAMPLE_RUST_MINIMAL=m'
+
+  rust-for-linux-samples:
+    path: "kernel/configs/rust-samples.config"
+    configs:
+      - 'CONFIG_SAMPLES=y'
+      - 'CONFIG_SAMPLES_RUST=y'
+      - 'CONFIG_SAMPLE_RUST_MINIMAL=m'
+      - 'CONFIG_SAMPLE_RUST_HOSTPROGS=m'
+      - 'CONFIG_SAMPLE_RUST_PRINT=m'
+      - 'CONFIG_SAMPLE_RUST_MODULE_PARAMETERS=m'
+      - 'CONFIG_SAMPLE_RUST_SYNC=m'
+      - 'CONFIG_SAMPLE_RUST_CHRDEV=m'
+      - 'CONFIG_SAMPLE_RUST_MISCDEV=m'
+      - 'CONFIG_SAMPLE_RUST_STACK_PROBING=m'
+      - 'CONFIG_SAMPLE_RUST_SEMAPHORE=m'
+      - 'CONFIG_SAMPLE_RUST_SEMAPHORE_C=m'
+      - 'CONFIG_SAMPLE_RUST_RANDOM=m'
+      - 'CONFIG_SAMPLE_RUST_PLATFORM=m'
+      - 'CONFIG_SAMPLE_RUST_FS=m'
+      - 'CONFIG_SAMPLE_RUST_NETFILTER=m'
+      - 'CONFIG_SAMPLE_RUST_ECHO_SERVER=m'
+      - 'CONFIG_SAMPLE_RUST_HOSTPROGS=m'
+      - 'CONFIG_SAMPLE_RUST_SELFTESTS=m'
+
   tinyconfig:
     path: "kernel/configs/tiny.config"
     defconfig: 'tinyconfig'
@@ -384,6 +423,10 @@ build_environments:
     arch_params:
       <<: *clang_12_arch_params
 
+  rustc-1.62:
+    cc: clang
+    cc_version: 16
+
 # Default config with full build coverage
 build_configs_defaults:
   variants:
@@ -939,6 +982,26 @@ build_configs:
     branch: 'v5.15-rt'
     variants: *preempt_rt_variants
 
+  rust:
+    tree: mainline
+    branch: 'master'
+    variants:
+      rustc-1.62:
+        build_environment: rustc-1.62
+        fragments: [rust, rust-samples]
+        architectures:
+          x86_64: *x86_64_arch
+
+  rust-for-linux:
+    tree: rust-for-linux
+    branch: 'rust'
+    variants:
+      rustc-1.62:
+        build_environment: rustc-1.62
+        fragments: [rust, rust-for-linux-samples]
+        architectures:
+          x86_64: *x86_64_arch
+
   samsung:
     tree: samsung
     branch: 'for-next'

config/docker/rustc-1.62.jinja2

@@ -0,0 +1,42 @@
+{% extends 'clang-15.jinja2' %}
+
+{% block packages %}
+{{ super() }}
+
+ENV RUST_VER=1.62.0
+ENV BINDGEN_VER=0.56.0
+
+ENV RUST_TRIPLE=rust-${RUST_VER}-x86_64-unknown-linux-gnu
+
+ENV CARGO_HOME=/usr/$RUST_TRIPLE/cargo
+
+ENV PATH=/usr/$RUST_TRIPLE/bin:${PATH}
+
+# fetch, validate and import the rust team key
+RUN wget https://static.rust-lang.org/rust-key.gpg.ascii
+RUN gpg --import --import-options show-only rust-key.gpg.ascii | \
+        grep -q 108F66205EAEB0AAA8DD5E1C85AB96E6FA1BE5FE
+RUN gpg --import rust-key.gpg.ascii
+
+# fetch, verify the toolchain
+RUN wget https://static.rust-lang.org/dist/${RUST_TRIPLE}.tar.gz
+RUN wget https://static.rust-lang.org/dist/${RUST_TRIPLE}.tar.gz.asc
+RUN gpg --verify ${RUST_TRIPLE}.tar.gz.asc ${RUST_TRIPLE}.tar.gz
+
+# install & cleanup tmp files
+RUN tar -xf ${RUST_TRIPLE}.tar.gz  -C /tmp/
+RUN /tmp/${RUST_TRIPLE}/install.sh --prefix=/usr/${RUST_TRIPLE} \
+        --components=rustc,cargo,rust-std-x86_64-unknown-linux-gnu
+RUN rm -rf /tmp/${RUST_TRIPLE}
+RUN rm /${RUST_TRIPLE}*
+
+RUN mkdir $CARGO_HOME
+RUN printf '[build]\nrustflags = ["-C", "linker=clang"]' > $CARGO_HOME/config.toml
+
+RUN git clone --recurse-submodules --branch $RUST_VER \
+        https://github.com/rust-lang/rust \
+        $(rustc --print sysroot)/lib/rustlib/src/rust
+
+RUN cargo install --locked --version $BINDGEN_VER bindgen
+
+{%- endblock %}