[PATCH 00/16] Enable rust support for linux kernel

[Harish.Sadineni@windriver.com]

From: Harish Sadineni <Harish.Sadineni@windriver.com>

This patch series introduces Rust support into the linux-yocto kernel recipe
and related build infrastructure in the Yocto Project. The goal is to enable
building the Linux kernel with Rust components and provide support for building 
kernel module which is written in rust and also provide support to build
rust kernel modules in sdk. 

And this series adds test for Linux Rust sample and also added support for out-of-tree kernel 
module written in Rust as well as associated test.

Summary of patches:

- Patch 01: Extend 'bindgen-cli' to support 'nativesdk', allowing it to be available in the SDK environment.
- Patch 02: Add required dependencies ('clang-native', 'rust-native', 'bindgen-cli-native') to the kernel to support Rust binding generation.
- Patch 03: Install the Rust standard library source ('library/') into `work-shared` and which will be later copied to
           linux-yocto recipe-sysroot-native.
- Patch 04: Added 'rust-kernel' to DISTRO_FEATURES_FILTER_NATIVE and DISTRO_FEATURES_FILTER_NATIVESDK, the 'rust-kernel' feature automatically
           propagates from target DISTRO_FEATURES to native/nativesdk builds
- Patch 05: Stage the Rust sources into `recipe-sysroot-native` for kernel build compatibility, making them visible during native builds.
- Patch 06: Update `kernel-yocto.bbclass` to invoke `make rustavailable` during 'do_kernel_configme', ensuring Rust readiness.
- Patch 07: Add kernel configuration support for Rust (via 'kernel-rust.scc'), enabling the Rust build options in kernel config.
- Patch 08: Fixed buildpaths errors when rust is enabled for kernel by appending --remap-path-prefix to RUST_DEBUG_REMAP
- Patch 09: Disabling ccache when rust-kernel is enabled for linux-yocto.
- Patch 10: Copy Rust kernel sources into kernel-devsrc build directory which will be required while running 'make prepare' in sdk.
- Patch 11: Added oe-selftest case for the Linux Rust sample.
- patch 12: Copying include/config/auto.conf in STAGING_KERNEL_BUILDDIR
- patch 13: Export artifacts needed for out-of-tree Rust compilation
- patch 14: Prepare out-of-tree rust module compilation
- patch 15: Added rust-out-of-tree-module recipe in meta-skeleton layer
- patch 16: Added rust-out-of-tree selftest

Patches have been build-tested successfully on:
- qemuarm64
- qemux86-64

Benchmark test-result for x86-64:
+-------------------------------+------------+-----------+-----------+-----------+
| DISTRO_FEATURES               |   real     |   user    |    sys    |  FS usage |
+-------------------------------+------------+-----------+-----------+-----------+
| rust-kernel (enabled)         | 46m1.720s  | 0m28.864s | 0m3.696s  |   58 GB   |
| rust-kernel (disabled)        | 30m1.053s  | 0m20.091s | 0m2.748s  |   33 GB   |
+-------------------------------+------------+-----------+-----------+-----------+

The increased in time & fs is due to kernel rust dependencies in
linux-yocto.


Harish Sadineni (9):
  bindgen-cli: extend BBCLASSEXTEND to include nativesdk
  linux-yocto: conditionally add clang/rust/bindgen-cli-native to
    DEPENDS
  rust: install Rust library sources for 'make rustavailable' support
  bitbake.conf: Include "rust-kernel" in native/nativesdk feature
    filters
  kernel-yocto: stage rustlib sources for linux-yocto 'make
    rustavailable' support
  kernel-yocto: add rust support via "make rustavailable" in
    do_kernel_configme
  linux-yocto: enable Rust support in kernel configuration
  kernel-yocto: Fix for buildpaths errors when rust is enabled for
    kernel
  kernel-devsrc: copying rust-kernel source to $kerneldir/build

Yoann Congal (7):
  kernel-yocto.bbclass: Disable ccache when rust-kernel is enabled
  selftest/cases/runtime_test: Add test for Linux Rust sample
  kernel.bbclass: Copy include/config/auto.conf in
    STAGING_KERNEL_BUILDDIR
  kernel.bbclass: Export artifacts needed for out-of-tree Rust
    compilation
  module.bbclass: Prepare out-of-tree rust module compilation
  meta-skeleton: Add rust-out-of-tree-module recipe
  runtime_test: Add rust-out-of-tree selftest

 .../rust-out-of-tree-module_git.bb            | 18 ++++++++++
 meta/classes-recipe/kernel-yocto.bbclass      | 28 +++++++++++++++
 meta/classes-recipe/kernel.bbclass            | 19 ++++++++++
 meta/classes-recipe/module.bbclass            |  8 +++++
 meta/conf/bitbake.conf                        |  4 +--
 meta/lib/oeqa/selftest/cases/runtime_test.py  | 35 +++++++++++++++++++
 .../bindgen-cli/bindgen-cli_0.72.1.bb         |  2 +-
 meta/recipes-devtools/rust/rust_1.91.1.bb     | 17 +++++++++
 meta/recipes-kernel/linux/kernel-devsrc.bb    |  4 +++
 meta/recipes-kernel/linux/linux-yocto.inc     |  2 ++
 meta/recipes-kernel/linux/linux-yocto_6.16.bb |  1 +
 meta/recipes-kernel/linux/linux-yocto_6.18.bb |  1 +
 12 files changed, 136 insertions(+), 3 deletions(-)
 create mode 100644 meta-skeleton/recipes-kernel/rust-out-of-tree-module/rust-out-of-tree-module_git.bb

-- 
2.49.0