Rust support
This is the patch series (v2) to add support for Rust as a second
language to the Linux kernel.
If you are interested in following this effort, please join us in
the mailing list at:
rust-for-linux@xxxxxxxxxxxxxxx
and take a look at the project itself at:
https://github.com/Rust-for-Linux
As usual, special thanks go to ISRG (Internet Security Research
Group) and Google for their financial support on this endeavor.
Cheers,
Miguel
--
# Rust support
This cover letter explains the major changes and updates done since
v1, plus a few extra notes and news. For the previous cover letters,
please see:
RFC: https://lore.kernel.org/lkml/20210414184604.23473-1-ojeda@xxxxxxxxxx/
v1: https://lore.kernel.org/lkml/20210704202756.29107-1-ojeda@xxxxxxxxxx/
## Infrastructure updates
There have been several improvements to the overall Rust support.
The following sections cover some of these.
### Stable compiler & Rust Edition 2021
We moved from the beta Rust compiler to using stable releases,
migrating each time a new one gets released. Currently we just moved
to Rust 1.57.0, released last Thursday.
By upgrading the compiler, we have been able to take off the list
a few unstable features we were using: `const_fn_transmute`,
`const_panic`, `const_unreachable_unchecked`, `core_panic` and
`try_reserve`. For an up-to-date list on the features and other
wishlists we have, please see:
https://github.com/Rust-for-Linux/linux/issues/2
We will keep upgrading until we do not rely on any unstable features;
at which point we may want to start declaring a minimum Rust version
is supported, like it is done for e.g. GCC and Clang.
Similarly, we also migrated to the 2021 edition of the Rust language.
### Customizing `core` and `alloc`
We added a couple more "modularization" options to `alloc` in order
to disable some features we do not need: `no_rc` and `no_sync`.
We would like to thank upstream Rust for working with us on
upstreaming these so that the kernel use case is well supported
(or, more precisely, the "combination" of options the kernel needs).
Upstream `core` has added `no_fp_fmt_parse` too, which we are using.
### Stricter code, docs and new lints
Following the `CONFIG_WERROR` discussions, we are trying to do our
bit by making the option apply to Rust code and having our CI build
with it enabled.
We also enabled a bunch of extra Rust compiler diagnostics and Clippy
lints. We may need to disable some of them in the future if they
prove too noisy or disruptive, but we think this is the best time
to try them out. For instance, one of them checks that no unreachable
public items are present.
One difference with respect to C here is that Rust diagnostics are
slightly more natural to disable within code, which we may allow us to
be more strict in the general case.
## Abstractions and driver updates
We added abstractions for sequence locks, power management callbacks,
io memory (`readX`/`writeX`), irq chips & high-level flow handlers,
gpio chips (including irq ones), devices, amba devices & drivers and
credentials.
There is improved driver support with bus-independent infrastructure,
revocable objects, revocable mutexes, efficient bit iterators, better
panic diagnostics and simplified pointer wrappers.
In addition, we improved and simplified `Ref` (`refcount_t`-backed)
objects and replaced all instances of Rust's `Arc` by it. Completely
removed `Arc` and `Rc` from the `alloc` crate.
A new driver for PL061 gpio devices was implemented and is submitted
as an RFC patch.
## Patch series status
Like we mentioned last time, the Rust support is still to be
considered experimental. However, support is good enough that kernel
developers can start working on the Rust abstractions for subsystems
and write drivers and other modules.
The current series has just arrived in `linux-next`, thus the first
run will happen in a day. Similarly, the preview docs for this series
can be seen at:
https://rust-for-linux.github.io/docs/kernel/
>From now on, we will also start submitting the patches regularly,
every two weeks or so.
## Industry and academia support
In addition to the statements from Arm, Google and Microsoft from
the previous cover letter, we have one from Red Hat this time:
There is interest in using Rust for kernel work that Red Hat
is considering.
## Conferences, meetings and liaisons
Kangrejos, the Rust for Linux conference we announced last time,
took place before LPC (made possible by Jonathan Corbet et. al. and
LPC's infrastructure). Thanks everyone that joined!
https://kangrejos.com
We would also want to thank you the venues we were invited to:
- Linaro Virtual Connect 2021 Fall
- Clang Built Linux Meetup II turbo
- Linux Plumbers Conference 2021 (quite a few Rust-related talks
from us and others as well!)
- Samsung Engineering Summit 2021
- Linux Foundation Live Mentorship Series
There will also be a talk in the Open Source Summit Japan this month.
We also want to thank Niko Matsakis and the Rust CTCFT (Cross Team
Collaboration Fun Times) team for inviting us to present our work
and our needs from Rust.
## Other related news
### `rustc_codegen_gcc` merged
The GCC backend for the Rust compiler (through `libgccjit`, although
used for ahead-of-time compilation) was merged into upstream Rust:
https://github.com/rust-lang/rustc_codegen_gcc
If the backend keeps progressing, we hope to soon be able to start
experimenting with compiling the Rust side of the kernel with GCC!
### Compiler Explorer improvements
This useful online tool added support for `rustc_codegen_gcc`.
Together with GCC Rust and `mrustc`, the site now supports all the
alternative Rust compilers. See a live example at:
https://godbolt.org/z/6br9Ef73E
They are also adding further options for Rust we requested, e.g. MIR
and macro expansion views are already live on the site.
## Acknowledgements
The signatures in the main commits correspond to the people that
wrote code that has ended up in them at the present time. For details
on contributions to code and discussions, please see our repository:
https://github.com/Rust-for-Linux/linux
However, we would like to give credit to everyone that has contributed
in one way or another to the Rust for Linux project. Since the v1:
- bjorn3 and Gary Guo for all the input on Rust compiler details
and all the reviews and suggestions.
- Jonathan Corbet and the LPC organizers for lending us the Linux
Plumbers Conference infrastructure so that we could have an easy
time setting up Kangrejos.
- Josh Triplett for reviewing the Rust CTCFT presentation.
- Robin Randhawa for reviewing the Linaro Connect presentation.
- Viresh Kumar for his work on adding Rust bindings to `libgpiod`.
- Philip Herrons (and his supporters Open Source Security and
Embecosm) et. al. for their ongoing work on GCC Rust.
- Antoni Boucher (and his supporters) et. al. for their ongoing
work on `rustc_codegen_gcc`.
- Mats Larsen, Marc Poulhiès et. al. for their ongoing work on
improving Rust support in Compiler Explorer.
- All the Rust and LLVM contributors taking a look into codegen
and other issues we have raised.
- Many folks that have reported issues, tested the project,
helped spread the word, joined discussions and contributed in
other ways!
Please also see the acknowledgements on the previous cover letters.
Boqun Feng (1):
kallsyms: use the correct buffer size for symbols
Gary Guo (2):
rust: add `build_error` crate
vsprintf: add new `%pA` format specifier
Miguel Ojeda (13):
kallsyms: support "big" kernel symbols
kallsyms: increase maximum kernel symbol length to 512
rust: add C helpers
rust: add `compiler_builtins` crate
rust: add `alloc` crate
rust: add `macros` crate
rust: export generated symbols
scripts: add `generate_rust_analyzer.py`
scripts: decode_stacktrace: demangle Rust symbols
docs: add Rust documentation
Kbuild: add Rust support
samples: add Rust examples
MAINTAINERS: Rust
Wedson Almeida Filho (3):
rust: add `kernel` crate
[RFC] drivers: gpio: PrimeCell PL061 in Rust
[RFC] drivers: android: Binder IPC in Rust
.gitignore | 5 +
.rustfmt.toml | 12 +
Documentation/doc-guide/kernel-doc.rst | 3 +
Documentation/index.rst | 1 +
Documentation/kbuild/kbuild.rst | 4 +
Documentation/process/changes.rst | 13 +
Documentation/rust/arch-support.rst | 35 +
Documentation/rust/assets/favicon-16x16.png | Bin 0 -> 798 bytes
Documentation/rust/assets/favicon-32x32.png | Bin 0 -> 2076 bytes
Documentation/rust/assets/rust-logo.png | Bin 0 -> 53976 bytes
Documentation/rust/coding.rst | 91 +
Documentation/rust/docs.rst | 101 +
Documentation/rust/index.rst | 21 +
Documentation/rust/quick-start.rst | 212 ++
MAINTAINERS | 14 +
Makefile | 146 +-
arch/arm/rust/target.json | 27 +
arch/arm64/rust/target.json | 34 +
arch/powerpc/rust/target.json | 29 +
arch/riscv/Makefile | 1 +
arch/riscv/rust/rv32ima.json | 36 +
arch/riscv/rust/rv32imac.json | 36 +
arch/riscv/rust/rv64ima.json | 36 +
arch/riscv/rust/rv64imac.json | 36 +
arch/x86/rust/target.json | 36 +
drivers/android/Kconfig | 7 +
drivers/android/Makefile | 2 +
drivers/android/allocation.rs | 266 ++
drivers/android/context.rs | 79 +
drivers/android/defs.rs | 99 +
drivers/android/node.rs | 476 +++
drivers/android/process.rs | 964 ++++++
drivers/android/range_alloc.rs | 189 ++
drivers/android/rust_binder.rs | 114 +
drivers/android/thread.rs | 871 +++++
drivers/android/transaction.rs | 326 ++
drivers/gpio/Kconfig | 8 +
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio_pl061_rust.rs | 362 ++
include/linux/kallsyms.h | 2 +-
include/linux/spinlock.h | 17 +-
include/uapi/linux/android/binder.h | 28 +-
init/Kconfig | 31 +-
kernel/kallsyms.c | 26 +-
kernel/livepatch/core.c | 4 +-
kernel/printk/printk.c | 5 +-
lib/Kconfig.debug | 144 +
lib/vsprintf.c | 12 +
rust/.gitignore | 7 +
rust/Makefile | 353 ++
rust/alloc/README.md | 32 +
rust/alloc/alloc.rs | 424 +++
rust/alloc/borrow.rs | 498 +++
rust/alloc/boxed.rs | 1844 ++++++++++
rust/alloc/collections/mod.rs | 155 +
rust/alloc/fmt.rs | 583 ++++
rust/alloc/lib.rs | 212 ++
rust/alloc/macros.rs | 126 +
rust/alloc/raw_vec.rs | 612 ++++
rust/alloc/slice.rs | 1275 +++++++
rust/alloc/str.rs | 621 ++++
rust/alloc/string.rs | 2857 ++++++++++++++++
rust/alloc/vec/drain.rs | 158 +
rust/alloc/vec/drain_filter.rs | 145 +
rust/alloc/vec/into_iter.rs | 356 ++
rust/alloc/vec/is_zero.rs | 106 +
rust/alloc/vec/mod.rs | 3327 +++++++++++++++++++
rust/alloc/vec/partial_eq.rs | 49 +
rust/alloc/vec/set_len_on_drop.rs | 30 +
rust/alloc/vec/spec_extend.rs | 172 +
rust/bindgen_parameters | 13 +
rust/build_error.rs | 29 +
rust/compiler_builtins.rs | 57 +
rust/exports.c | 16 +
rust/helpers.c | 436 +++
rust/kernel/allocator.rs | 65 +
rust/kernel/amba.rs | 276 ++
rust/kernel/bindings.rs | 47 +
rust/kernel/bindings_helper.h | 30 +
rust/kernel/buffer.rs | 52 +
rust/kernel/build_assert.rs | 80 +
rust/kernel/c_types.rs | 119 +
rust/kernel/chrdev.rs | 212 ++
rust/kernel/cred.rs | 73 +
rust/kernel/device.rs | 206 ++
rust/kernel/driver.rs | 198 ++
rust/kernel/error.rs | 542 +++
rust/kernel/file.rs | 141 +
rust/kernel/file_operations.rs | 723 ++++
rust/kernel/gpio.rs | 475 +++
rust/kernel/io_buffer.rs | 153 +
rust/kernel/io_mem.rs | 207 ++
rust/kernel/iov_iter.rs | 81 +
rust/kernel/irq.rs | 408 +++
rust/kernel/lib.rs | 256 ++
rust/kernel/linked_list.rs | 247 ++
rust/kernel/miscdev.rs | 166 +
rust/kernel/module_param.rs | 497 +++
rust/kernel/of.rs | 101 +
rust/kernel/pages.rs | 162 +
rust/kernel/platdev.rs | 152 +
rust/kernel/power.rs | 118 +
rust/kernel/prelude.rs | 33 +
rust/kernel/print.rs | 441 +++
rust/kernel/random.rs | 50 +
rust/kernel/raw_list.rs | 361 ++
rust/kernel/rbtree.rs | 562 ++++
rust/kernel/revocable.rs | 163 +
rust/kernel/security.rs | 36 +
rust/kernel/static_assert.rs | 39 +
rust/kernel/std_vendor.rs | 150 +
rust/kernel/str.rs | 375 +++
rust/kernel/sync/arc.rs | 500 +++
rust/kernel/sync/condvar.rs | 137 +
rust/kernel/sync/guard.rs | 181 +
rust/kernel/sync/locked_by.rs | 112 +
rust/kernel/sync/mod.rs | 92 +
rust/kernel/sync/mutex.rs | 111 +
rust/kernel/sync/revocable_mutex.rs | 184 +
rust/kernel/sync/seqlock.rs | 201 ++
rust/kernel/sync/spinlock.rs | 180 +
rust/kernel/sysctl.rs | 197 ++
rust/kernel/task.rs | 182 +
rust/kernel/types.rs | 486 +++
rust/kernel/user_ptr.rs | 175 +
rust/macros/helpers.rs | 79 +
rust/macros/lib.rs | 94 +
rust/macros/module.rs | 622 ++++
samples/Kconfig | 2 +
samples/Makefile | 1 +
samples/rust/Kconfig | 113 +
samples/rust/Makefile | 12 +
samples/rust/rust_chrdev.rs | 50 +
samples/rust/rust_minimal.rs | 38 +
samples/rust/rust_miscdev.rs | 149 +
samples/rust/rust_module_parameters.rs | 72 +
samples/rust/rust_print.rs | 57 +
samples/rust/rust_random.rs | 61 +
samples/rust/rust_semaphore.rs | 174 +
samples/rust/rust_semaphore_c.c | 212 ++
samples/rust/rust_stack_probing.rs | 40 +
samples/rust/rust_sync.rs | 81 +
scripts/Makefile.build | 22 +
scripts/Makefile.debug | 10 +
scripts/Makefile.lib | 12 +
scripts/Makefile.modfinal | 8 +-
scripts/decode_stacktrace.sh | 14 +
scripts/generate_rust_analyzer.py | 133 +
scripts/is_rust_module.sh | 19 +
scripts/kallsyms.c | 40 +-
scripts/kconfig/confdata.c | 75 +
scripts/rust-version.sh | 31 +
tools/include/linux/kallsyms.h | 2 +-
tools/include/linux/lockdep.h | 2 +-
tools/lib/perf/include/perf/event.h | 2 +-
tools/lib/symbol/kallsyms.h | 2 +-
156 files changed, 32369 insertions(+), 50 deletions(-)
create mode 100644 .rustfmt.toml
create mode 100644 Documentation/rust/arch-support.rst
create mode 100644 Documentation/rust/assets/favicon-16x16.png
create mode 100644 Documentation/rust/assets/favicon-32x32.png
create mode 100644 Documentation/rust/assets/rust-logo.png
create mode 100644 Documentation/rust/coding.rst
create mode 100644 Documentation/rust/docs.rst
create mode 100644 Documentation/rust/index.rst
create mode 100644 Documentation/rust/quick-start.rst
create mode 100644 arch/arm/rust/target.json
create mode 100644 arch/arm64/rust/target.json
create mode 100644 arch/powerpc/rust/target.json
create mode 100644 arch/riscv/rust/rv32ima.json
create mode 100644 arch/riscv/rust/rv32imac.json
create mode 100644 arch/riscv/rust/rv64ima.json
create mode 100644 arch/riscv/rust/rv64imac.json
create mode 100644 arch/x86/rust/target.json
create mode 100644 drivers/android/allocation.rs
create mode 100644 drivers/android/context.rs
create mode 100644 drivers/android/defs.rs
create mode 100644 drivers/android/node.rs
create mode 100644 drivers/android/process.rs
create mode 100644 drivers/android/range_alloc.rs
create mode 100644 drivers/android/rust_binder.rs
create mode 100644 drivers/android/thread.rs
create mode 100644 drivers/android/transaction.rs
create mode 100644 drivers/gpio/gpio_pl061_rust.rs
create mode 100644 rust/.gitignore
create mode 100644 rust/Makefile
create mode 100644 rust/alloc/README.md
create mode 100644 rust/alloc/alloc.rs
create mode 100644 rust/alloc/borrow.rs
create mode 100644 rust/alloc/boxed.rs
create mode 100644 rust/alloc/collections/mod.rs
create mode 100644 rust/alloc/fmt.rs
create mode 100644 rust/alloc/lib.rs
create mode 100644 rust/alloc/macros.rs
create mode 100644 rust/alloc/raw_vec.rs
create mode 100644 rust/alloc/slice.rs
create mode 100644 rust/alloc/str.rs
create mode 100644 rust/alloc/string.rs
create mode 100644 rust/alloc/vec/drain.rs
create mode 100644 rust/alloc/vec/drain_filter.rs
create mode 100644 rust/alloc/vec/into_iter.rs
create mode 100644 rust/alloc/vec/is_zero.rs
create mode 100644 rust/alloc/vec/mod.rs
create mode 100644 rust/alloc/vec/partial_eq.rs
create mode 100644 rust/alloc/vec/set_len_on_drop.rs
create mode 100644 rust/alloc/vec/spec_extend.rs
create mode 100644 rust/bindgen_parameters
create mode 100644 rust/build_error.rs
create mode 100644 rust/compiler_builtins.rs
create mode 100644 rust/exports.c
create mode 100644 rust/helpers.c
create mode 100644 rust/kernel/allocator.rs
create mode 100644 rust/kernel/amba.rs
create mode 100644 rust/kernel/bindings.rs
create mode 100644 rust/kernel/bindings_helper.h
create mode 100644 rust/kernel/buffer.rs
create mode 100644 rust/kernel/build_assert.rs
create mode 100644 rust/kernel/c_types.rs
create mode 100644 rust/kernel/chrdev.rs
create mode 100644 rust/kernel/cred.rs
create mode 100644 rust/kernel/device.rs
create mode 100644 rust/kernel/driver.rs
create mode 100644 rust/kernel/error.rs
create mode 100644 rust/kernel/file.rs
create mode 100644 rust/kernel/file_operations.rs
create mode 100644 rust/kernel/gpio.rs
create mode 100644 rust/kernel/io_buffer.rs
create mode 100644 rust/kernel/io_mem.rs
create mode 100644 rust/kernel/iov_iter.rs
create mode 100644 rust/kernel/irq.rs
create mode 100644 rust/kernel/lib.rs
create mode 100644 rust/kernel/linked_list.rs
create mode 100644 rust/kernel/miscdev.rs
create mode 100644 rust/kernel/module_param.rs
create mode 100644 rust/kernel/of.rs
create mode 100644 rust/kernel/pages.rs
create mode 100644 rust/kernel/platdev.rs
create mode 100644 rust/kernel/power.rs
create mode 100644 rust/kernel/prelude.rs
create mode 100644 rust/kernel/print.rs
create mode 100644 rust/kernel/random.rs
create mode 100644 rust/kernel/raw_list.rs
create mode 100644 rust/kernel/rbtree.rs
create mode 100644 rust/kernel/revocable.rs
create mode 100644 rust/kernel/security.rs
create mode 100644 rust/kernel/static_assert.rs
create mode 100644 rust/kernel/std_vendor.rs
create mode 100644 rust/kernel/str.rs
create mode 100644 rust/kernel/sync/arc.rs
create mode 100644 rust/kernel/sync/condvar.rs
create mode 100644 rust/kernel/sync/guard.rs
create mode 100644 rust/kernel/sync/locked_by.rs
create mode 100644 rust/kernel/sync/mod.rs
create mode 100644 rust/kernel/sync/mutex.rs
create mode 100644 rust/kernel/sync/revocable_mutex.rs
create mode 100644 rust/kernel/sync/seqlock.rs
create mode 100644 rust/kernel/sync/spinlock.rs
create mode 100644 rust/kernel/sysctl.rs
create mode 100644 rust/kernel/task.rs
create mode 100644 rust/kernel/types.rs
create mode 100644 rust/kernel/user_ptr.rs
create mode 100644 rust/macros/helpers.rs
create mode 100644 rust/macros/lib.rs
create mode 100644 rust/macros/module.rs
create mode 100644 samples/rust/Kconfig
create mode 100644 samples/rust/Makefile
create mode 100644 samples/rust/rust_chrdev.rs
create mode 100644 samples/rust/rust_minimal.rs
create mode 100644 samples/rust/rust_miscdev.rs
create mode 100644 samples/rust/rust_module_parameters.rs
create mode 100644 samples/rust/rust_print.rs
create mode 100644 samples/rust/rust_random.rs
create mode 100644 samples/rust/rust_semaphore.rs
create mode 100644 samples/rust/rust_semaphore_c.c
create mode 100644 samples/rust/rust_stack_probing.rs
create mode 100644 samples/rust/rust_sync.rs
create mode 100755 scripts/generate_rust_analyzer.py
create mode 100755 scripts/is_rust_module.sh
create mode 100755 scripts/rust-version.sh
--
2.34.0
