* [PATCH v9 00/27] Rust support
@ 2022-08-05 15:41 Miguel Ojeda
2022-08-05 15:42 ` [PATCH v9 23/27] Kbuild: add " Miguel Ojeda
2022-08-05 15:42 ` [PATCH v9 24/27] docs: add Rust documentation Miguel Ojeda
0 siblings, 2 replies; 9+ messages in thread
From: Miguel Ojeda @ 2022-08-05 15:41 UTC (permalink / raw)
To: Linus Torvalds, Greg Kroah-Hartman
Cc: rust-for-linux, linux-kernel, linux-fsdevel, patches,
Jarkko Sakkinen, Miguel Ojeda, linux-doc, linux-kbuild,
linux-perf-users, live-patching
Rust support
This is the patch series (v9) 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@vger.kernel.org
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
the previous ones. For those, please see:
RFC: https://lore.kernel.org/lkml/20210414184604.23473-1-ojeda@kernel.org/
v1: https://lore.kernel.org/lkml/20210704202756.29107-1-ojeda@kernel.org/
v2: https://lore.kernel.org/lkml/20211206140313.5653-1-ojeda@kernel.org/
v3: https://lore.kernel.org/lkml/20220117053349.6804-1-ojeda@kernel.org/
v4: https://lore.kernel.org/lkml/20220212130410.6901-1-ojeda@kernel.org/
v5: https://lore.kernel.org/lkml/20220317181032.15436-1-ojeda@kernel.org/
v6: https://lore.kernel.org/lkml/20220507052451.12890-1-ojeda@kernel.org/
v7: https://lore.kernel.org/lkml/20220523020209.11810-1-ojeda@kernel.org/
v8: https://lore.kernel.org/lkml/20220802015052.10452-1-ojeda@kernel.org/
This is a trimmed down v8. It has enough support to compile a minimal
Rust kernel module, with the aim to get the "core" support in first
and then start upstreaming the rest piece by piece.
The kernel module is able to create a `Vec<i32>` (a contiguous,
growable array type), push some numbers and print them on unload to
the kernel log with the `pr_info!` macro.
The patch series could be made even more minimal by removing some of
that too, but this seemed like a good balance.
After the diet regime, 3% of the `kernel` crate remains (down to 500
lines), 60% of `alloc`, and the "adapt `alloc`" commit is 100 lines.
Overall, we went from 40 to 13 klines.
Most of the code has been around in linux-next for some months now,
but to trim down things I had to do minor changes. In any case, please
let me know if this selection is in line with what you expected.
## Patch series status
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 will appear in the next `linux-next`, as usual.
I have kept the docs as they were in v8 since they showcase best what
the docs would eventually look like:
https://rust-for-linux.github.io/docs/kernel/
As usual, please see the following link for the live list of unstable
Rust features we are using (note that this trimmed version does not
require all of them):
https://github.com/Rust-for-Linux/linux/issues/2
## Conferences, meetings and liaisons
Join us in LPC 2022 (Linux Plumbers Conference) for the Rust MC
(microconference)! The schedule is available at:
https://lpc.events/event/16/sessions/150/
We will be talking about GCC Rust (the Rust frontend for GCC),
`rustc_codegen_gcc` (the GCC backend for `rustc`), Rust for Linux,
the Rust NVMe driver, the integration of Rust with the Kernel Testing
Service and Rust in the Kernel (via eBPF).
In addition, I would like to personally thank Google and ISRG
(Internet Security Research Group) for sponsoring Kangrejos,
the Rust for Linux workshop:
https://kangrejos.com
## 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
previous cover letter:
- Boqun Feng, Konstantin Shelekhin and David Laight for their
reviews of some of the v8 patches.
- Matthew Wilcox, Greg Kroah-Hartman, Rasmus Villemoes and Christoph
Hellwig for their feedback on v8.
- Björn Roy Baron, Gary Guo and Boqun Feng for stepping up as
reviewers in `MAINTAINERS`.
- Jon Olson for working on a `cpu` module with utilities for
SMP systems.
- Alice Ryhl for working on adding `BINDER_TYPE_PTR` support.
- FUJITA Tomonori for working on PCI support for a NVMe Rust driver.
- Andreas Reindl for working on adding missing `SAFETY` comments.
- Wei Liu for taking the time to answer questions from newcomers
in Zulip.
- Philip Li, Yujie Liu et al. for continuing their work on adding
Rust support to the Intel 0DAY/LKP kernel test robot.
- Philip Herron and Arthur Cohen (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`.
- Emilio Cobos Álvarez et al. for their work on `bindgen`, including
on issues that affect the kernel.
- Mats Larsen, Marc Poulhiès et al. for their ongoing work on
improving Rust support in Compiler Explorer.
- Many folks that have reported issues, tested the project,
helped spread the word, joined discussions and contributed in
other ways!
Please see also the acknowledgements on the previous cover letters.
Boqun Feng (2):
kallsyms: use `sizeof` instead of hardcoded size
kallsyms: avoid hardcoding buffer size
Daniel Xu (1):
scripts: add `is_rust_module.sh`
Gary Guo (1):
vsprintf: add new `%pA` format specifier
Miguel Ojeda (22):
kallsyms: add static relationship between `KSYM_NAME_LEN{,_BUFFER}`
kallsyms: support "big" kernel symbols
kallsyms: increase maximum kernel symbol length to 512
rust: add C helpers
rust: import upstream `alloc` crate
rust: adapt `alloc` crate to the kernel
rust: add `compiler_builtins` crate
rust: add `macros` crate
rust: add `bindings` crate
rust: export generated symbols
scripts: checkpatch: diagnose uses of `%pA` in the C side as errors
scripts: checkpatch: enable language-independent checks for Rust
scripts: decode_stacktrace: demangle Rust symbols
scripts: add `generate_rust_analyzer.py`
scripts: add `generate_rust_target.rs`
scripts: add `rust_is_available.sh`
rust: add `.rustfmt.toml`
Kbuild: add Rust support
docs: add Rust documentation
x86: enable initial Rust support
samples: add first Rust examples
MAINTAINERS: Rust
Wedson Almeida Filho (1):
rust: add `kernel` crate
.gitignore | 6 +
.rustfmt.toml | 12 +
Documentation/core-api/printk-formats.rst | 10 +
Documentation/doc-guide/kernel-doc.rst | 3 +
Documentation/index.rst | 1 +
Documentation/kbuild/kbuild.rst | 17 +
Documentation/kbuild/makefiles.rst | 50 +-
Documentation/process/changes.rst | 41 +
Documentation/rust/arch-support.rst | 19 +
Documentation/rust/coding-guidelines.rst | 216 ++
Documentation/rust/general-information.rst | 79 +
Documentation/rust/index.rst | 22 +
Documentation/rust/quick-start.rst | 232 ++
MAINTAINERS | 18 +
Makefile | 172 +-
arch/Kconfig | 6 +
arch/x86/Kconfig | 1 +
arch/x86/Makefile | 10 +
include/linux/compiler_types.h | 6 +-
include/linux/kallsyms.h | 2 +-
init/Kconfig | 46 +-
kernel/configs/rust.config | 1 +
kernel/kallsyms.c | 26 +-
kernel/livepatch/core.c | 4 +-
lib/Kconfig.debug | 34 +
lib/vsprintf.c | 13 +
rust/.gitignore | 8 +
rust/Makefile | 381 +++
rust/alloc/README.md | 33 +
rust/alloc/alloc.rs | 440 +++
rust/alloc/borrow.rs | 498 +++
rust/alloc/boxed.rs | 2028 +++++++++++
rust/alloc/collections/mod.rs | 156 +
rust/alloc/lib.rs | 244 ++
rust/alloc/raw_vec.rs | 527 +++
rust/alloc/slice.rs | 1204 +++++++
rust/alloc/vec/drain.rs | 186 ++
rust/alloc/vec/drain_filter.rs | 145 +
rust/alloc/vec/into_iter.rs | 366 ++
rust/alloc/vec/is_zero.rs | 120 +
rust/alloc/vec/mod.rs | 3140 ++++++++++++++++++
rust/alloc/vec/partial_eq.rs | 49 +
rust/bindgen_parameters | 21 +
rust/bindings/bindings_helper.h | 13 +
rust/bindings/lib.rs | 53 +
rust/compiler_builtins.rs | 63 +
rust/exports.c | 21 +
rust/helpers.c | 51 +
rust/kernel/allocator.rs | 64 +
rust/kernel/error.rs | 59 +
rust/kernel/lib.rs | 78 +
rust/kernel/prelude.rs | 20 +
rust/kernel/print.rs | 198 ++
rust/kernel/str.rs | 72 +
rust/macros/helpers.rs | 51 +
rust/macros/lib.rs | 72 +
rust/macros/module.rs | 282 ++
samples/Kconfig | 2 +
samples/Makefile | 1 +
samples/rust/Kconfig | 30 +
samples/rust/Makefile | 5 +
samples/rust/hostprogs/.gitignore | 3 +
samples/rust/hostprogs/Makefile | 5 +
samples/rust/hostprogs/a.rs | 7 +
samples/rust/hostprogs/b.rs | 5 +
samples/rust/hostprogs/single.rs | 12 +
samples/rust/rust_minimal.rs | 38 +
scripts/.gitignore | 1 +
scripts/Kconfig.include | 6 +-
scripts/Makefile | 3 +
scripts/Makefile.build | 60 +
scripts/Makefile.debug | 10 +
scripts/Makefile.host | 34 +-
scripts/Makefile.lib | 12 +
scripts/Makefile.modfinal | 8 +-
scripts/cc-version.sh | 12 +-
scripts/checkpatch.pl | 12 +-
scripts/decode_stacktrace.sh | 14 +
scripts/generate_rust_analyzer.py | 135 +
scripts/generate_rust_target.rs | 182 +
scripts/is_rust_module.sh | 16 +
scripts/kallsyms.c | 47 +-
scripts/kconfig/confdata.c | 75 +
scripts/min-tool-version.sh | 6 +
scripts/rust_is_available.sh | 160 +
scripts/rust_is_available_bindgen_libclang.h | 2 +
tools/include/linux/kallsyms.h | 2 +-
tools/lib/perf/include/perf/event.h | 2 +-
tools/lib/symbol/kallsyms.h | 2 +-
89 files changed, 12548 insertions(+), 51 deletions(-)
create mode 100644 .rustfmt.toml
create mode 100644 Documentation/rust/arch-support.rst
create mode 100644 Documentation/rust/coding-guidelines.rst
create mode 100644 Documentation/rust/general-information.rst
create mode 100644 Documentation/rust/index.rst
create mode 100644 Documentation/rust/quick-start.rst
create mode 100644 kernel/configs/rust.config
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/lib.rs
create mode 100644 rust/alloc/raw_vec.rs
create mode 100644 rust/alloc/slice.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/bindgen_parameters
create mode 100644 rust/bindings/bindings_helper.h
create mode 100644 rust/bindings/lib.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/error.rs
create mode 100644 rust/kernel/lib.rs
create mode 100644 rust/kernel/prelude.rs
create mode 100644 rust/kernel/print.rs
create mode 100644 rust/kernel/str.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/hostprogs/.gitignore
create mode 100644 samples/rust/hostprogs/Makefile
create mode 100644 samples/rust/hostprogs/a.rs
create mode 100644 samples/rust/hostprogs/b.rs
create mode 100644 samples/rust/hostprogs/single.rs
create mode 100644 samples/rust/rust_minimal.rs
create mode 100755 scripts/generate_rust_analyzer.py
create mode 100644 scripts/generate_rust_target.rs
create mode 100755 scripts/is_rust_module.sh
create mode 100755 scripts/rust_is_available.sh
create mode 100644 scripts/rust_is_available_bindgen_libclang.h
base-commit: 3d7cb6b04c3f3115719235cc6866b10326de34cd
--
2.37.1
^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH v9 23/27] Kbuild: add Rust support
2022-08-05 15:41 [PATCH v9 00/27] Rust support Miguel Ojeda
@ 2022-08-05 15:42 ` Miguel Ojeda
2022-08-17 20:26 ` Kees Cook
` (2 more replies)
2022-08-05 15:42 ` [PATCH v9 24/27] docs: add Rust documentation Miguel Ojeda
1 sibling, 3 replies; 9+ messages in thread
From: Miguel Ojeda @ 2022-08-05 15:42 UTC (permalink / raw)
To: Linus Torvalds, Greg Kroah-Hartman
Cc: rust-for-linux, linux-kernel, linux-fsdevel, patches,
Jarkko Sakkinen, Miguel Ojeda, Alex Gaynor, Finn Behrens,
Adam Bratschi-Kaye, Wedson Almeida Filho, Michael Ellerman,
Sven Van Asbroeck, Gary Guo, Boris-Chengbiao Zhou, Boqun Feng,
Douglas Su, Dariusz Sosnowski, Antonio Terceiro, Daniel Xu,
Björn Roy Baron, Martin Rodriguez Reboredo, Masahiro Yamada,
Michal Marek, Nick Desaulniers, linux-kbuild
Having most of the new files in place, we now enable Rust support
in the build system, including `Kconfig` entries related to Rust,
the Rust configuration printer and a few other bits.
Co-developed-by: Alex Gaynor <alex.gaynor@gmail.com>
Signed-off-by: Alex Gaynor <alex.gaynor@gmail.com>
Co-developed-by: Finn Behrens <me@kloenk.de>
Signed-off-by: Finn Behrens <me@kloenk.de>
Co-developed-by: Adam Bratschi-Kaye <ark.email@gmail.com>
Signed-off-by: Adam Bratschi-Kaye <ark.email@gmail.com>
Co-developed-by: Wedson Almeida Filho <wedsonaf@google.com>
Signed-off-by: Wedson Almeida Filho <wedsonaf@google.com>
Co-developed-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Co-developed-by: Sven Van Asbroeck <thesven73@gmail.com>
Signed-off-by: Sven Van Asbroeck <thesven73@gmail.com>
Co-developed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Gary Guo <gary@garyguo.net>
Co-developed-by: Boris-Chengbiao Zhou <bobo1239@web.de>
Signed-off-by: Boris-Chengbiao Zhou <bobo1239@web.de>
Co-developed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Co-developed-by: Douglas Su <d0u9.su@outlook.com>
Signed-off-by: Douglas Su <d0u9.su@outlook.com>
Co-developed-by: Dariusz Sosnowski <dsosnowski@dsosnowski.pl>
Signed-off-by: Dariusz Sosnowski <dsosnowski@dsosnowski.pl>
Co-developed-by: Antonio Terceiro <antonio.terceiro@linaro.org>
Signed-off-by: Antonio Terceiro <antonio.terceiro@linaro.org>
Co-developed-by: Daniel Xu <dxu@dxuuu.xyz>
Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
Co-developed-by: Björn Roy Baron <bjorn3_gh@protonmail.com>
Signed-off-by: Björn Roy Baron <bjorn3_gh@protonmail.com>
Co-developed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Signed-off-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
.gitignore | 2 +
Makefile | 172 ++++++++++++++-
arch/Kconfig | 6 +
include/linux/compiler_types.h | 6 +-
init/Kconfig | 46 +++-
kernel/configs/rust.config | 1 +
lib/Kconfig.debug | 34 +++
rust/.gitignore | 8 +
rust/Makefile | 381 +++++++++++++++++++++++++++++++++
rust/bindgen_parameters | 21 ++
scripts/Kconfig.include | 6 +-
scripts/Makefile | 3 +
scripts/Makefile.build | 60 ++++++
scripts/Makefile.debug | 10 +
scripts/Makefile.host | 34 ++-
scripts/Makefile.lib | 12 ++
scripts/Makefile.modfinal | 8 +-
scripts/cc-version.sh | 12 +-
scripts/kconfig/confdata.c | 75 +++++++
scripts/min-tool-version.sh | 6 +
20 files changed, 877 insertions(+), 26 deletions(-)
create mode 100644 kernel/configs/rust.config
create mode 100644 rust/.gitignore
create mode 100644 rust/Makefile
create mode 100644 rust/bindgen_parameters
diff --git a/.gitignore b/.gitignore
index 97e085d613a2..5da004814678 100644
--- a/.gitignore
+++ b/.gitignore
@@ -37,6 +37,8 @@
*.o
*.o.*
*.patch
+*.rmeta
+*.rsi
*.s
*.so
*.so.dbg
diff --git a/Makefile b/Makefile
index df92892325ae..a105cb893b4c 100644
--- a/Makefile
+++ b/Makefile
@@ -120,6 +120,15 @@ endif
export KBUILD_CHECKSRC
+# Enable "clippy" (a linter) as part of the Rust compilation.
+#
+# Use 'make CLIPPY=1' to enable it.
+ifeq ("$(origin CLIPPY)", "command line")
+ KBUILD_CLIPPY := $(CLIPPY)
+endif
+
+export KBUILD_CLIPPY
+
# Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
# directory of external module to build. Setting M= takes precedence.
ifeq ("$(origin M)", "command line")
@@ -267,14 +276,14 @@ no-dot-config-targets := $(clean-targets) \
cscope gtags TAGS tags help% %docs check% coccicheck \
$(version_h) headers headers_% archheaders archscripts \
%asm-generic kernelversion %src-pkg dt_binding_check \
- outputmakefile
+ outputmakefile rustavailable rustfmt rustfmtcheck
# Installation targets should not require compiler. Unfortunately, vdso_install
# is an exception where build artifacts may be updated. This must be fixed.
no-compiler-targets := $(no-dot-config-targets) install dtbs_install \
headers_install modules_install kernelrelease image_name
no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease \
image_name
-single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
+single-targets := %.a %.i %.rsi %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
config-build :=
mixed-build :=
@@ -436,6 +445,7 @@ else
HOSTCC = gcc
HOSTCXX = g++
endif
+HOSTRUSTC = rustc
HOSTPKG_CONFIG = pkg-config
KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
@@ -444,8 +454,26 @@ KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
KBUILD_USERCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(USERCFLAGS)
KBUILD_USERLDFLAGS := $(USERLDFLAGS)
+# These flags apply to all Rust code in the tree, including the kernel and
+# host programs.
+export rust_common_flags := --edition=2021 \
+ -Zbinary_dep_depinfo=y \
+ -Dunsafe_op_in_unsafe_fn -Drust_2018_idioms \
+ -Dunreachable_pub -Dnon_ascii_idents \
+ -Wmissing_docs \
+ -Drustdoc::missing_crate_level_docs \
+ -Dclippy::correctness -Dclippy::style \
+ -Dclippy::suspicious -Dclippy::complexity \
+ -Dclippy::perf \
+ -Dclippy::let_unit_value -Dclippy::mut_mut \
+ -Dclippy::needless_bitwise_bool \
+ -Dclippy::needless_continue \
+ -Wclippy::dbg_macro
+
KBUILD_HOSTCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
+KBUILD_HOSTRUSTFLAGS := $(rust_common_flags) -O -Cstrip=debuginfo \
+ -Zallow-features= $(HOSTRUSTFLAGS)
KBUILD_HOSTLDFLAGS := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
KBUILD_HOSTLDLIBS := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
@@ -470,6 +498,12 @@ OBJDUMP = $(CROSS_COMPILE)objdump
READELF = $(CROSS_COMPILE)readelf
STRIP = $(CROSS_COMPILE)strip
endif
+RUSTC = rustc
+RUSTDOC = rustdoc
+RUSTFMT = rustfmt
+CLIPPY_DRIVER = clippy-driver
+BINDGEN = bindgen
+CARGO = cargo
PAHOLE = pahole
RESOLVE_BTFIDS = $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
LEX = flex
@@ -495,9 +529,11 @@ CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
-Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
NOSTDINC_FLAGS :=
CFLAGS_MODULE =
+RUSTFLAGS_MODULE =
AFLAGS_MODULE =
LDFLAGS_MODULE =
CFLAGS_KERNEL =
+RUSTFLAGS_KERNEL =
AFLAGS_KERNEL =
LDFLAGS_vmlinux =
@@ -526,15 +562,42 @@ KBUILD_CFLAGS := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
-Werror=return-type -Wno-format-security \
-std=gnu11
KBUILD_CPPFLAGS := -D__KERNEL__
+KBUILD_RUSTFLAGS := $(rust_common_flags) \
+ --target=$(objtree)/rust/target.json \
+ -Cpanic=abort -Cembed-bitcode=n -Clto=n \
+ -Cforce-unwind-tables=n -Ccodegen-units=1 \
+ -Csymbol-mangling-version=v0 \
+ -Crelocation-model=static \
+ -Zfunction-sections=n \
+ -Dclippy::float_arithmetic
+
KBUILD_AFLAGS_KERNEL :=
KBUILD_CFLAGS_KERNEL :=
+KBUILD_RUSTFLAGS_KERNEL :=
KBUILD_AFLAGS_MODULE := -DMODULE
KBUILD_CFLAGS_MODULE := -DMODULE
+KBUILD_RUSTFLAGS_MODULE := --cfg MODULE
KBUILD_LDFLAGS_MODULE :=
KBUILD_LDFLAGS :=
CLANG_FLAGS :=
+ifeq ($(KBUILD_CLIPPY),1)
+ RUSTC_OR_CLIPPY_QUIET := CLIPPY
+ RUSTC_OR_CLIPPY = $(CLIPPY_DRIVER)
+else
+ RUSTC_OR_CLIPPY_QUIET := RUSTC
+ RUSTC_OR_CLIPPY = $(RUSTC)
+endif
+
+ifdef RUST_LIB_SRC
+ export RUST_LIB_SRC
+endif
+
+export RUSTC_BOOTSTRAP := 1
+
export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG
+export RUSTC RUSTDOC RUSTFMT RUSTC_OR_CLIPPY_QUIET RUSTC_OR_CLIPPY BINDGEN CARGO
+export HOSTRUSTC KBUILD_HOSTRUSTFLAGS
export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
@@ -543,9 +606,10 @@ export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS
export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
+export KBUILD_RUSTFLAGS RUSTFLAGS_KERNEL RUSTFLAGS_MODULE
export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
-export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
-export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
+export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_RUSTFLAGS_MODULE KBUILD_LDFLAGS_MODULE
+export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL KBUILD_RUSTFLAGS_KERNEL
export PAHOLE_FLAGS
# Files to ignore in find ... statements
@@ -726,7 +790,7 @@ $(KCONFIG_CONFIG):
#
# Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
# so you cannot notice that Kconfig is waiting for the user input.
-%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h: $(KCONFIG_CONFIG)
+%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h %/generated/rustc_cfg: $(KCONFIG_CONFIG)
$(Q)$(kecho) " SYNC $@"
$(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
else # !may-sync-config
@@ -755,12 +819,20 @@ KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
KBUILD_CFLAGS += -O2
+KBUILD_RUSTFLAGS += -Copt-level=2
else ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3
KBUILD_CFLAGS += -O3
+KBUILD_RUSTFLAGS += -Copt-level=3
else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
KBUILD_CFLAGS += -Os
+KBUILD_RUSTFLAGS += -Copt-level=s
endif
+# Always set `debug-assertions` and `overflow-checks` because their default
+# depends on `opt-level` and `debug-assertions`, respectively.
+KBUILD_RUSTFLAGS += -Cdebug-assertions=$(if $(CONFIG_RUST_DEBUG_ASSERTIONS),y,n)
+KBUILD_RUSTFLAGS += -Coverflow-checks=$(if $(CONFIG_RUST_OVERFLOW_CHECKS),y,n)
+
# Tell gcc to never replace conditional load with a non-conditional one
ifdef CONFIG_CC_IS_GCC
# gcc-10 renamed --param=allow-store-data-races=0 to
@@ -791,6 +863,9 @@ KBUILD_CFLAGS-$(CONFIG_WERROR) += -Werror
KBUILD_CFLAGS-$(CONFIG_CC_NO_ARRAY_BOUNDS) += -Wno-array-bounds
KBUILD_CFLAGS += $(KBUILD_CFLAGS-y) $(CONFIG_CC_IMPLICIT_FALLTHROUGH)
+KBUILD_RUSTFLAGS-$(CONFIG_WERROR) += -Dwarnings
+KBUILD_RUSTFLAGS += $(KBUILD_RUSTFLAGS-y)
+
ifdef CONFIG_CC_IS_CLANG
KBUILD_CPPFLAGS += -Qunused-arguments
# The kernel builds with '-std=gnu11' so use of GNU extensions is acceptable.
@@ -811,12 +886,15 @@ KBUILD_CFLAGS += $(call cc-disable-warning, dangling-pointer)
ifdef CONFIG_FRAME_POINTER
KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
+KBUILD_RUSTFLAGS += -Cforce-frame-pointers=y
else
# Some targets (ARM with Thumb2, for example), can't be built with frame
# pointers. For those, we don't have FUNCTION_TRACER automatically
# select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
# incompatible with -fomit-frame-pointer with current GCC, so we don't use
# -fomit-frame-pointer with FUNCTION_TRACER.
+# In the Rust target specification, "frame-pointer" is set explicitly
+# to "may-omit".
ifndef CONFIG_FUNCTION_TRACER
KBUILD_CFLAGS += -fomit-frame-pointer
endif
@@ -881,8 +959,10 @@ ifdef CONFIG_DEBUG_SECTION_MISMATCH
KBUILD_CFLAGS += -fno-inline-functions-called-once
endif
+# `rustc`'s `-Zfunction-sections` applies to data too (as of 1.59.0).
ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
+KBUILD_RUSTFLAGS_KERNEL += -Zfunction-sections=y
LDFLAGS_vmlinux += --gc-sections
endif
@@ -1025,10 +1105,11 @@ include $(addprefix $(srctree)/, $(include-y))
# Do not add $(call cc-option,...) below this line. When you build the kernel
# from the clean source tree, the GCC plugins do not exist at this point.
-# Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
+# Add user supplied CPPFLAGS, AFLAGS, CFLAGS and RUSTFLAGS as the last assignments
KBUILD_CPPFLAGS += $(KCPPFLAGS)
KBUILD_AFLAGS += $(KAFLAGS)
KBUILD_CFLAGS += $(KCFLAGS)
+KBUILD_RUSTFLAGS += $(KRUSTFLAGS)
KBUILD_LDFLAGS_MODULE += --build-id=sha1
LDFLAGS_vmlinux += --build-id=sha1
@@ -1097,6 +1178,7 @@ export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
ifeq ($(KBUILD_EXTMOD),)
core-y += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/
core-$(CONFIG_BLOCK) += block/
+core-$(CONFIG_RUST) += rust/
vmlinux-dirs := $(patsubst %/,%,$(filter %/, \
$(core-y) $(core-m) $(drivers-y) $(drivers-m) \
@@ -1201,6 +1283,10 @@ prepare0: archprepare
# All the preparing..
prepare: prepare0
+ifdef CONFIG_RUST
+ $(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh -v
+ $(Q)$(MAKE) $(build)=rust
+endif
PHONY += remove-stale-files
remove-stale-files:
@@ -1490,7 +1576,7 @@ endif # CONFIG_MODULES
# Directories & files removed with 'make clean'
CLEAN_FILES += include/ksym vmlinux.symvers modules-only.symvers \
modules.builtin modules.builtin.modinfo modules.nsdeps \
- compile_commands.json .thinlto-cache
+ compile_commands.json .thinlto-cache rust/test rust/doc
# Directories & files removed with 'make mrproper'
MRPROPER_FILES += include/config include/generated \
@@ -1501,7 +1587,8 @@ MRPROPER_FILES += include/config include/generated \
certs/signing_key.pem \
certs/x509.genkey \
vmlinux-gdb.py \
- *.spec
+ *.spec \
+ rust/target.json rust/libmacros.so
# clean - Delete most, but leave enough to build external modules
#
@@ -1526,6 +1613,9 @@ $(mrproper-dirs):
mrproper: clean $(mrproper-dirs)
$(call cmd,rmfiles)
+ @find . $(RCS_FIND_IGNORE) \
+ \( -name '*.rmeta' \) \
+ -type f -print | xargs rm -f
# distclean
#
@@ -1613,6 +1703,24 @@ help:
@echo ' kselftest-merge - Merge all the config dependencies of'
@echo ' kselftest to existing .config.'
@echo ''
+ @echo 'Rust targets:'
+ @echo ' rustavailable - Checks whether the Rust toolchain is'
+ @echo ' available and, if not, explains why.'
+ @echo ' rustfmt - Reformat all the Rust code in the kernel'
+ @echo ' rustfmtcheck - Checks if all the Rust code in the kernel'
+ @echo ' is formatted, printing a diff otherwise.'
+ @echo ' rustdoc - Generate Rust documentation'
+ @echo ' (requires kernel .config)'
+ @echo ' rusttest - Runs the Rust tests'
+ @echo ' (requires kernel .config; downloads external repos)'
+ @echo ' rust-analyzer - Generate rust-project.json rust-analyzer support file'
+ @echo ' (requires kernel .config)'
+ @echo ' dir/file.[os] - Build specified target only'
+ @echo ' dir/file.rsi - Build macro expanded source, similar to C preprocessing.'
+ @echo ' Run with RUSTFMT=n to skip reformatting if needed.'
+ @echo ' The output is not intended to be compilable.'
+ @echo ' dir/file.ll - Build the LLVM assembly file'
+ @echo ''
@$(if $(dtstree), \
echo 'Devicetree:'; \
echo '* dtbs - Build device tree blobs for enabled boards'; \
@@ -1685,6 +1793,52 @@ PHONY += $(DOC_TARGETS)
$(DOC_TARGETS):
$(Q)$(MAKE) $(build)=Documentation $@
+
+# Rust targets
+# ---------------------------------------------------------------------------
+
+# "Is Rust available?" target
+PHONY += rustavailable
+rustavailable:
+ $(Q)$(CONFIG_SHELL) $(srctree)/scripts/rust_is_available.sh -v && echo "Rust is available!"
+
+# Documentation target
+#
+# Using the singular to avoid running afoul of `no-dot-config-targets`.
+PHONY += rustdoc
+rustdoc: prepare
+ $(Q)$(MAKE) $(build)=rust $@
+
+# Testing target
+PHONY += rusttest
+rusttest: prepare
+ $(Q)$(MAKE) $(build)=rust $@
+
+# Formatting targets
+PHONY += rustfmt rustfmtcheck
+
+# We skip `rust/alloc` since we want to minimize the diff w.r.t. upstream.
+#
+# We match using absolute paths since `find` does not resolve them
+# when matching, which is a problem when e.g. `srctree` is `..`.
+# We `grep` afterwards in order to remove the directory entry itself.
+rustfmt:
+ $(Q)find $(abs_srctree) -type f -name '*.rs' \
+ -o -path $(abs_srctree)/rust/alloc -prune \
+ -o -path $(abs_objtree)/rust/test -prune \
+ | grep -Fv $(abs_srctree)/rust/alloc \
+ | grep -Fv $(abs_objtree)/rust/test \
+ | grep -Fv generated \
+ | xargs $(RUSTFMT) $(rustfmt_flags)
+
+rustfmtcheck: rustfmt_flags = --check
+rustfmtcheck: rustfmt
+
+# IDE support targets
+PHONY += rust-analyzer
+rust-analyzer:
+ $(Q)$(MAKE) $(build)=rust $@
+
# Misc
# ---------------------------------------------------------------------------
@@ -1852,7 +2006,7 @@ $(clean-dirs):
clean: $(clean-dirs)
$(call cmd,rmfiles)
@find $(or $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
- \( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
+ \( -name '*.[aios]' -o -name '*.rsi' -o -name '*.ko' -o -name '.*.cmd' \
-o -name '*.ko.*' \
-o -name '*.dtb' -o -name '*.dtbo' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
-o -name '*.dwo' -o -name '*.lst' \
diff --git a/arch/Kconfig b/arch/Kconfig
index 71b9272acb28..d5038cf8dd49 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -353,6 +353,12 @@ config HAVE_RSEQ
This symbol should be selected by an architecture if it
supports an implementation of restartable sequences.
+config HAVE_RUST
+ bool
+ help
+ This symbol should be selected by an architecture if it
+ supports Rust.
+
config HAVE_FUNCTION_ARG_ACCESS_API
bool
help
diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h
index 4f2a819fd60a..50b3f6b9502e 100644
--- a/include/linux/compiler_types.h
+++ b/include/linux/compiler_types.h
@@ -4,8 +4,12 @@
#ifndef __ASSEMBLY__
+/*
+ * Skipped when running bindgen due to a libclang issue;
+ * see https://github.com/rust-lang/rust-bindgen/issues/2244.
+ */
#if defined(CONFIG_DEBUG_INFO_BTF) && defined(CONFIG_PAHOLE_HAS_BTF_TAG) && \
- __has_attribute(btf_type_tag)
+ __has_attribute(btf_type_tag) && !defined(__BINDGEN__)
# define BTF_TYPE_TAG(value) __attribute__((btf_type_tag(#value)))
#else
# define BTF_TYPE_TAG(value) /* nothing */
diff --git a/init/Kconfig b/init/Kconfig
index c7900e8975f1..ff0636891bc1 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -60,6 +60,17 @@ config LLD_VERSION
default $(ld-version) if LD_IS_LLD
default 0
+config RUST_IS_AVAILABLE
+ def_bool $(success,$(srctree)/scripts/rust_is_available.sh)
+ help
+ This shows whether a suitable Rust toolchain is available (found).
+
+ Please see Documentation/rust/quick-start.rst for instructions on how
+ to satify the build requirements of Rust support.
+
+ In particular, the Makefile target 'rustavailable' is useful to check
+ why the Rust toolchain is not being detected.
+
config CC_CAN_LINK
bool
default $(success,$(srctree)/scripts/cc-can-link.sh $(CC) $(CLANG_FLAGS) $(USERCFLAGS) $(USERLDFLAGS) $(m64-flag)) if 64BIT
@@ -151,7 +162,8 @@ config WERROR
default COMPILE_TEST
help
A kernel build should not cause any compiler warnings, and this
- enables the '-Werror' flag to enforce that rule by default.
+ enables the '-Werror' (for C) and '-Dwarnings' (for Rust) flags
+ to enforce that rule by default.
However, if you have a new (or very old) compiler with odd and
unusual warnings, or you have some architecture with problems,
@@ -1898,6 +1910,38 @@ config PROFILING
Say Y here to enable the extended profiling support mechanisms used
by profilers.
+config RUST
+ bool "Rust support"
+ depends on HAVE_RUST
+ depends on RUST_IS_AVAILABLE
+ depends on !MODVERSIONS
+ depends on !GCC_PLUGINS
+ depends on !RANDSTRUCT
+ depends on !DEBUG_INFO_BTF
+ select CONSTRUCTORS
+ help
+ Enables Rust support in the kernel.
+
+ This allows other Rust-related options, like drivers written in Rust,
+ to be selected.
+
+ It is also required to be able to load external kernel modules
+ written in Rust.
+
+ See Documentation/rust/ for more information.
+
+ If unsure, say N.
+
+config RUSTC_VERSION_TEXT
+ string
+ depends on RUST
+ default $(shell,command -v $(RUSTC) >/dev/null 2>&1 && $(RUSTC) --version || echo n)
+
+config BINDGEN_VERSION_TEXT
+ string
+ depends on RUST
+ default $(shell,command -v $(BINDGEN) >/dev/null 2>&1 && $(BINDGEN) --version || echo n)
+
#
# Place an empty function call at each tracepoint site. Can be
# dynamically changed for a probe function.
diff --git a/kernel/configs/rust.config b/kernel/configs/rust.config
new file mode 100644
index 000000000000..38a7c5362c9c
--- /dev/null
+++ b/kernel/configs/rust.config
@@ -0,0 +1 @@
+CONFIG_RUST=y
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 2e24db4bff19..06af1cd68e95 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -2688,6 +2688,40 @@ config HYPERV_TESTING
endmenu # "Kernel Testing and Coverage"
+menu "Rust hacking"
+
+config RUST_DEBUG_ASSERTIONS
+ bool "Debug assertions"
+ depends on RUST
+ help
+ Enables rustc's `-Cdebug-assertions` codegen option.
+
+ This flag lets you turn `cfg(debug_assertions)` conditional
+ compilation on or off. This can be used to enable extra debugging
+ code in development but not in production. For example, it controls
+ the behavior of the standard library's `debug_assert!` macro.
+
+ Note that this will apply to all Rust code, including `core`.
+
+ If unsure, say N.
+
+config RUST_OVERFLOW_CHECKS
+ bool "Overflow checks"
+ default y
+ depends on RUST
+ help
+ Enables rustc's `-Coverflow-checks` codegen option.
+
+ This flag allows you to control the behavior of runtime integer
+ overflow. When overflow-checks are enabled, a Rust panic will occur
+ on overflow.
+
+ Note that this will apply to all Rust code, including `core`.
+
+ If unsure, say Y.
+
+endmenu # "Rust"
+
source "Documentation/Kconfig"
endmenu # Kernel hacking
diff --git a/rust/.gitignore b/rust/.gitignore
new file mode 100644
index 000000000000..9bd1af8e05a1
--- /dev/null
+++ b/rust/.gitignore
@@ -0,0 +1,8 @@
+# SPDX-License-Identifier: GPL-2.0
+
+target.json
+bindings_generated.rs
+bindings_helpers_generated.rs
+exports_*_generated.h
+doc/
+test/
diff --git a/rust/Makefile b/rust/Makefile
new file mode 100644
index 000000000000..7700d3853404
--- /dev/null
+++ b/rust/Makefile
@@ -0,0 +1,381 @@
+# SPDX-License-Identifier: GPL-2.0
+
+always-$(CONFIG_RUST) += target.json
+no-clean-files += target.json
+
+obj-$(CONFIG_RUST) += core.o compiler_builtins.o
+always-$(CONFIG_RUST) += exports_core_generated.h
+
+# Missing prototypes are expected in the helpers since these are exported
+# for Rust only, thus there is no header nor prototypes.
+obj-$(CONFIG_RUST) += helpers.o
+CFLAGS_REMOVE_helpers.o = -Wmissing-prototypes -Wmissing-declarations
+
+always-$(CONFIG_RUST) += libmacros.so
+no-clean-files += libmacros.so
+
+always-$(CONFIG_RUST) += bindings/bindings_generated.rs bindings/bindings_helpers_generated.rs
+obj-$(CONFIG_RUST) += alloc.o bindings.o kernel.o
+always-$(CONFIG_RUST) += exports_alloc_generated.h exports_bindings_generated.h \
+ exports_kernel_generated.h
+
+obj-$(CONFIG_RUST) += exports.o
+
+# Avoids running `$(RUSTC)` for the sysroot when it may not be available.
+ifdef CONFIG_RUST
+
+# `$(rust_flags)` is passed in case the user added `--sysroot`.
+rustc_sysroot := $(shell $(RUSTC) $(rust_flags) --print sysroot)
+rustc_host_target := $(shell $(RUSTC) --version --verbose | grep -F 'host: ' | cut -d' ' -f2)
+RUST_LIB_SRC ?= $(rustc_sysroot)/lib/rustlib/src/rust/library
+
+ifeq ($(quiet),silent_)
+cargo_quiet=-q
+rust_test_quiet=-q
+rustdoc_test_quiet=--test-args -q
+else ifeq ($(quiet),quiet_)
+rust_test_quiet=-q
+rustdoc_test_quiet=--test-args -q
+else
+cargo_quiet=--verbose
+endif
+
+core-cfgs = \
+ --cfg no_fp_fmt_parse
+
+alloc-cfgs = \
+ --cfg no_fmt \
+ --cfg no_global_oom_handling \
+ --cfg no_macros \
+ --cfg no_rc \
+ --cfg no_str \
+ --cfg no_string \
+ --cfg no_sync \
+ --cfg no_thin
+
+quiet_cmd_rustdoc = RUSTDOC $(if $(rustdoc_host),H, ) $<
+ cmd_rustdoc = \
+ OBJTREE=$(abspath $(objtree)) \
+ $(RUSTDOC) $(if $(rustdoc_host),$(rust_common_flags),$(rust_flags)) \
+ $(rustc_target_flags) -L$(objtree)/$(obj) \
+ --output $(objtree)/$(obj)/doc \
+ --crate-name $(subst rustdoc-,,$@) \
+ @$(objtree)/include/generated/rustc_cfg $<
+
+# The `html_logo_url` and `html_favicon_url` forms of the `doc` attribute
+# can be used to specify a custom logo. However:
+# - The given value is used as-is, thus it cannot be relative or a local file
+# (unlike the non-custom case) since the generated docs have subfolders.
+# - It requires adding it to every crate.
+# - It requires changing `core` which comes from the sysroot.
+#
+# Using `-Zcrate-attr` would solve the last two points, but not the first.
+# The https://github.com/rust-lang/rfcs/pull/3226 RFC suggests two new
+# command-like flags to solve the issue. Meanwhile, we use the non-custom case
+# and then retouch the generated files.
+rustdoc: rustdoc-core rustdoc-macros rustdoc-compiler_builtins \
+ rustdoc-alloc rustdoc-kernel
+ $(Q)cp $(srctree)/Documentation/images/logo.svg $(objtree)/$(obj)/doc
+ $(Q)cp $(srctree)/Documentation/images/COPYING-logo $(objtree)/$(obj)/doc
+ $(Q)find $(objtree)/$(obj)/doc -name '*.html' -type f -print0 | xargs -0 sed -Ei \
+ -e 's:rust-logo\.svg:logo.svg:g' \
+ -e 's:rust-logo\.png:logo.svg:g' \
+ -e 's:favicon\.svg:logo.svg:g' \
+ -e 's:<link rel="alternate icon" type="image/png" href="[./]*favicon-(16x16|32x32)\.png">::g'
+ $(Q)echo '.logo-container > img { object-fit: contain; }' \
+ >> $(objtree)/$(obj)/doc/rustdoc.css
+
+rustdoc-macros: private rustdoc_host = yes
+rustdoc-macros: private rustc_target_flags = --crate-type proc-macro \
+ --extern proc_macro
+rustdoc-macros: $(src)/macros/lib.rs FORCE
+ $(call if_changed,rustdoc)
+
+rustdoc-core: private rustc_target_flags = $(core-cfgs)
+rustdoc-core: $(RUST_LIB_SRC)/core/src/lib.rs FORCE
+ $(call if_changed,rustdoc)
+
+rustdoc-compiler_builtins: $(src)/compiler_builtins.rs rustdoc-core FORCE
+ $(call if_changed,rustdoc)
+
+# We need to allow `rustdoc::broken_intra_doc_links` because some
+# `no_global_oom_handling` functions refer to non-`no_global_oom_handling`
+# functions. Ideally `rustdoc` would have a way to distinguish broken links
+# due to things that are "configured out" vs. entirely non-existing ones.
+rustdoc-alloc: private rustc_target_flags = $(alloc-cfgs) \
+ -Arustdoc::broken_intra_doc_links
+rustdoc-alloc: $(src)/alloc/lib.rs rustdoc-core rustdoc-compiler_builtins FORCE
+ $(call if_changed,rustdoc)
+
+rustdoc-kernel: private rustc_target_flags = --extern alloc \
+ --extern macros=$(objtree)/$(obj)/libmacros.so \
+ --extern bindings
+rustdoc-kernel: $(src)/kernel/lib.rs rustdoc-core rustdoc-macros \
+ rustdoc-compiler_builtins rustdoc-alloc $(obj)/libmacros.so \
+ $(obj)/bindings.o FORCE
+ $(call if_changed,rustdoc)
+
+quiet_cmd_rustc_test_library = RUSTC TL $<
+ cmd_rustc_test_library = \
+ OBJTREE=$(abspath $(objtree)) \
+ $(RUSTC) $(rust_common_flags) \
+ @$(objtree)/include/generated/rustc_cfg $(rustc_target_flags) \
+ --crate-type $(if $(rustc_test_library_proc),proc-macro,rlib) \
+ --out-dir $(objtree)/$(obj)/test --cfg testlib \
+ --sysroot $(objtree)/$(obj)/test/sysroot \
+ -L$(objtree)/$(obj)/test \
+ --crate-name $(subst rusttest-,,$(subst rusttestlib-,,$@)) $<
+
+rusttestlib-macros: private rustc_target_flags = --extern proc_macro
+rusttestlib-macros: private rustc_test_library_proc = yes
+rusttestlib-macros: $(src)/macros/lib.rs rusttest-prepare FORCE
+ $(call if_changed,rustc_test_library)
+
+rusttestlib-bindings: $(src)/bindings/lib.rs rusttest-prepare FORCE
+ $(call if_changed,rustc_test_library)
+
+quiet_cmd_rustdoc_test = RUSTDOC T $<
+ cmd_rustdoc_test = \
+ OBJTREE=$(abspath $(objtree)) \
+ $(RUSTDOC) --test $(rust_common_flags) \
+ @$(objtree)/include/generated/rustc_cfg \
+ $(rustc_target_flags) $(rustdoc_test_target_flags) \
+ --sysroot $(objtree)/$(obj)/test/sysroot $(rustdoc_test_quiet) \
+ -L$(objtree)/$(obj)/test --output $(objtree)/$(obj)/doc \
+ --crate-name $(subst rusttest-,,$@) $<
+
+# We cannot use `-Zpanic-abort-tests` because some tests are dynamic,
+# so for the moment we skip `-Cpanic=abort`.
+quiet_cmd_rustc_test = RUSTC T $<
+ cmd_rustc_test = \
+ OBJTREE=$(abspath $(objtree)) \
+ $(RUSTC) --test $(rust_common_flags) \
+ @$(objtree)/include/generated/rustc_cfg \
+ $(rustc_target_flags) --out-dir $(objtree)/$(obj)/test \
+ --sysroot $(objtree)/$(obj)/test/sysroot \
+ -L$(objtree)/$(obj)/test \
+ --crate-name $(subst rusttest-,,$@) $<; \
+ $(objtree)/$(obj)/test/$(subst rusttest-,,$@) $(rust_test_quiet) \
+ $(rustc_test_run_flags)
+
+rusttest: rusttest-macros rusttest-kernel
+
+# This prepares a custom sysroot with our custom `alloc` instead of
+# the standard one.
+#
+# This requires several hacks:
+# - Unlike `core` and `alloc`, `std` depends on more than a dozen crates,
+# including third-party crates that need to be downloaded, plus custom
+# `build.rs` steps. Thus hardcoding things here is not maintainable.
+# - `cargo` knows how to build the standard library, but it is an unstable
+# feature so far (`-Zbuild-std`).
+# - `cargo` only considers the use case of building the standard library
+# to use it in a given package. Thus we need to create a dummy package
+# and pick the generated libraries from there.
+# - Since we only keep a subset of upstream `alloc` in-tree, we need
+# to recreate it on the fly by putting our sources on top.
+# - The usual ways of modifying the dependency graph in `cargo` do not seem
+# to apply for the `-Zbuild-std` steps, thus we have to mislead it
+# by modifying the sources in the sysroot.
+# - To avoid messing with the user's Rust installation, we create a clone
+# of the sysroot. However, `cargo` ignores `RUSTFLAGS` in the `-Zbuild-std`
+# steps, thus we use a wrapper binary passed via `RUSTC` to pass the flag.
+#
+# In the future, we hope to avoid the whole ordeal by either:
+# - Making the `test` crate not depend on `std` (either improving upstream
+# or having our own custom crate).
+# - Making the tests run in kernel space (requires the previous point).
+# - Making `std` and friends be more like a "normal" crate, so that
+# `-Zbuild-std` and related hacks are not needed.
+quiet_cmd_rustsysroot = RUSTSYSROOT
+ cmd_rustsysroot = \
+ rm -rf $(objtree)/$(obj)/test; \
+ mkdir -p $(objtree)/$(obj)/test; \
+ cp -a $(rustc_sysroot) $(objtree)/$(obj)/test/sysroot; \
+ cp -r $(srctree)/$(src)/alloc/* \
+ $(objtree)/$(obj)/test/sysroot/lib/rustlib/src/rust/library/alloc/src; \
+ echo '\#!/bin/sh' > $(objtree)/$(obj)/test/rustc_sysroot; \
+ echo "$(RUSTC) --sysroot=$(abspath $(objtree)/$(obj)/test/sysroot) \"\$$@\"" \
+ >> $(objtree)/$(obj)/test/rustc_sysroot; \
+ chmod u+x $(objtree)/$(obj)/test/rustc_sysroot; \
+ $(CARGO) -q new $(objtree)/$(obj)/test/dummy; \
+ RUSTC=$(objtree)/$(obj)/test/rustc_sysroot $(CARGO) $(cargo_quiet) \
+ test -Zbuild-std --target $(rustc_host_target) \
+ --manifest-path $(objtree)/$(obj)/test/dummy/Cargo.toml; \
+ rm $(objtree)/$(obj)/test/sysroot/lib/rustlib/$(rustc_host_target)/lib/*; \
+ cp $(objtree)/$(obj)/test/dummy/target/$(rustc_host_target)/debug/deps/* \
+ $(objtree)/$(obj)/test/sysroot/lib/rustlib/$(rustc_host_target)/lib
+
+rusttest-prepare: FORCE
+ $(call if_changed,rustsysroot)
+
+rusttest-macros: private rustc_target_flags = --extern proc_macro
+rusttest-macros: private rustdoc_test_target_flags = --crate-type proc-macro
+rusttest-macros: $(src)/macros/lib.rs rusttest-prepare FORCE
+ $(call if_changed,rustc_test)
+ $(call if_changed,rustdoc_test)
+
+rusttest-kernel: private rustc_target_flags = --extern alloc \
+ --extern macros --extern bindings
+rusttest-kernel: $(src)/kernel/lib.rs rusttest-prepare \
+ rusttestlib-macros rusttestlib-bindings FORCE
+ $(call if_changed,rustc_test)
+ $(call if_changed,rustc_test_library)
+
+filechk_rust_target = $(objtree)/scripts/generate_rust_target < $<
+
+$(obj)/target.json: $(objtree)/include/config/auto.conf FORCE
+ $(call filechk,rust_target)
+
+ifdef CONFIG_CC_IS_CLANG
+bindgen_c_flags = $(c_flags)
+else
+# bindgen relies on libclang to parse C. Ideally, bindgen would support a GCC
+# plugin backend and/or the Clang driver would be perfectly compatible with GCC.
+#
+# For the moment, here we are tweaking the flags on the fly. This is a hack,
+# and some kernel configurations may not work (e.g. `GCC_PLUGIN_RANDSTRUCT`
+# if we end up using one of those structs).
+bindgen_skip_c_flags := -mno-fp-ret-in-387 -mpreferred-stack-boundary=% \
+ -mskip-rax-setup -mgeneral-regs-only -msign-return-address=% \
+ -mindirect-branch=thunk-extern -mindirect-branch-register \
+ -mfunction-return=thunk-extern -mrecord-mcount -mabi=lp64 \
+ -mindirect-branch-cs-prefix -mstack-protector-guard% -mtraceback=no \
+ -mno-pointers-to-nested-functions -mno-string \
+ -mno-strict-align -mstrict-align \
+ -fconserve-stack -falign-jumps=% -falign-loops=% \
+ -femit-struct-debug-baseonly -fno-ipa-cp-clone -fno-ipa-sra \
+ -fno-partial-inlining -fplugin-arg-arm_ssp_per_task_plugin-% \
+ -fno-reorder-blocks -fno-allow-store-data-races -fasan-shadow-offset=% \
+ -fzero-call-used-regs=% -fno-stack-clash-protection \
+ -fno-inline-functions-called-once \
+ --param=% --param asan-%
+
+# Derived from `scripts/Makefile.clang`.
+BINDGEN_TARGET_x86 := x86_64-linux-gnu
+BINDGEN_TARGET := $(BINDGEN_TARGET_$(SRCARCH))
+
+# All warnings are inhibited since GCC builds are very experimental,
+# many GCC warnings are not supported by Clang, they may only appear in
+# some configurations, with new GCC versions, etc.
+bindgen_extra_c_flags = -w --target=$(BINDGEN_TARGET)
+
+bindgen_c_flags = $(filter-out $(bindgen_skip_c_flags), $(c_flags)) \
+ $(bindgen_extra_c_flags)
+endif
+
+ifdef CONFIG_LTO
+bindgen_c_flags_lto = $(filter-out $(CC_FLAGS_LTO), $(bindgen_c_flags))
+else
+bindgen_c_flags_lto = $(bindgen_c_flags)
+endif
+
+bindgen_c_flags_final = $(bindgen_c_flags_lto) -D__BINDGEN__
+
+quiet_cmd_bindgen = BINDGEN $@
+ cmd_bindgen = \
+ $(BINDGEN) $< $(bindgen_target_flags) \
+ --use-core --with-derive-default --ctypes-prefix core::ffi --no-layout-tests \
+ --no-debug '.*' \
+ --size_t-is-usize -o $@ -- $(bindgen_c_flags_final) -DMODULE \
+ $(bindgen_target_cflags) $(bindgen_target_extra)
+
+$(obj)/bindings/bindings_generated.rs: private bindgen_target_flags = \
+ $(shell grep -v '^\#\|^$$' $(srctree)/$(src)/bindgen_parameters)
+$(obj)/bindings/bindings_generated.rs: $(src)/bindings/bindings_helper.h \
+ $(src)/bindgen_parameters FORCE
+ $(call if_changed_dep,bindgen)
+
+# See `CFLAGS_REMOVE_helpers.o` above. In addition, Clang on C does not warn
+# with `-Wmissing-declarations` (unlike GCC), so it is not strictly needed here
+# given it is `libclang`; but for consistency, future Clang changes and/or
+# a potential future GCC backend for `bindgen`, we disable it too.
+$(obj)/bindings/bindings_helpers_generated.rs: private bindgen_target_flags = \
+ --blacklist-type '.*' --whitelist-var '' \
+ --whitelist-function 'rust_helper_.*'
+$(obj)/bindings/bindings_helpers_generated.rs: private bindgen_target_cflags = \
+ -I$(objtree)/$(obj) -Wno-missing-prototypes -Wno-missing-declarations
+$(obj)/bindings/bindings_helpers_generated.rs: private bindgen_target_extra = ; \
+ sed -Ei 's/pub fn rust_helper_([a-zA-Z0-9_]*)/#[link_name="rust_helper_\1"]\n pub fn \1/g' $@
+$(obj)/bindings/bindings_helpers_generated.rs: $(src)/helpers.c FORCE
+ $(call if_changed_dep,bindgen)
+
+quiet_cmd_exports = EXPORTS $@
+ cmd_exports = \
+ $(NM) -p --defined-only $< \
+ | grep -E ' (T|R|D) ' | cut -d ' ' -f 3 \
+ | xargs -Isymbol \
+ echo 'EXPORT_SYMBOL_RUST_GPL(symbol);' > $@
+
+$(obj)/exports_core_generated.h: $(obj)/core.o FORCE
+ $(call if_changed,exports)
+
+$(obj)/exports_alloc_generated.h: $(obj)/alloc.o FORCE
+ $(call if_changed,exports)
+
+$(obj)/exports_bindings_generated.h: $(obj)/bindings.o FORCE
+ $(call if_changed,exports)
+
+$(obj)/exports_kernel_generated.h: $(obj)/kernel.o FORCE
+ $(call if_changed,exports)
+
+quiet_cmd_rustc_procmacro = $(RUSTC_OR_CLIPPY_QUIET) P $@
+ cmd_rustc_procmacro = \
+ $(RUSTC_OR_CLIPPY) $(rust_common_flags) \
+ --emit=dep-info,link --extern proc_macro \
+ --crate-type proc-macro --out-dir $(objtree)/$(obj) \
+ --crate-name $(patsubst lib%.so,%,$(notdir $@)) $<; \
+ mv $(objtree)/$(obj)/$(patsubst lib%.so,%,$(notdir $@)).d $(depfile); \
+ sed -i '/^\#/d' $(depfile)
+
+# Procedural macros can only be used with the `rustc` that compiled it.
+# Therefore, to get `libmacros.so` automatically recompiled when the compiler
+# version changes, we add `core.o` as a dependency (even if it is not needed).
+$(obj)/libmacros.so: $(src)/macros/lib.rs $(obj)/core.o FORCE
+ $(call if_changed_dep,rustc_procmacro)
+
+quiet_cmd_rustc_library = $(if $(skip_clippy),RUSTC,$(RUSTC_OR_CLIPPY_QUIET)) L $@
+ cmd_rustc_library = \
+ OBJTREE=$(abspath $(objtree)) \
+ $(if $(skip_clippy),$(RUSTC),$(RUSTC_OR_CLIPPY)) \
+ $(filter-out $(skip_flags),$(rust_flags) $(rustc_target_flags)) \
+ --emit=dep-info,obj,metadata --crate-type rlib \
+ --out-dir $(objtree)/$(obj) -L$(objtree)/$(obj) \
+ --crate-name $(patsubst %.o,%,$(notdir $@)) $<; \
+ mv $(objtree)/$(obj)/$(patsubst %.o,%,$(notdir $@)).d $(depfile); \
+ sed -i '/^\#/d' $(depfile) \
+ $(if $(rustc_objcopy),;$(OBJCOPY) $(rustc_objcopy) $@)
+
+rust-analyzer:
+ $(Q)$(srctree)/scripts/generate_rust_analyzer.py $(srctree) $(objtree) \
+ $(RUST_LIB_SRC) > $(objtree)/rust-project.json
+
+$(obj)/core.o: private skip_clippy = 1
+$(obj)/core.o: private skip_flags = -Dunreachable_pub
+$(obj)/core.o: private rustc_target_flags = $(core-cfgs)
+$(obj)/core.o: $(RUST_LIB_SRC)/core/src/lib.rs $(obj)/target.json FORCE
+ $(call if_changed_dep,rustc_library)
+
+$(obj)/compiler_builtins.o: private rustc_objcopy = -w -W '__*'
+$(obj)/compiler_builtins.o: $(src)/compiler_builtins.rs $(obj)/core.o FORCE
+ $(call if_changed_dep,rustc_library)
+
+$(obj)/alloc.o: private skip_clippy = 1
+$(obj)/alloc.o: private skip_flags = -Dunreachable_pub
+$(obj)/alloc.o: private rustc_target_flags = $(alloc-cfgs)
+$(obj)/alloc.o: $(src)/alloc/lib.rs $(obj)/compiler_builtins.o FORCE
+ $(call if_changed_dep,rustc_library)
+
+$(obj)/bindings.o: $(src)/bindings/lib.rs \
+ $(obj)/compiler_builtins.o \
+ $(obj)/bindings/bindings_generated.rs \
+ $(obj)/bindings/bindings_helpers_generated.rs FORCE
+ $(call if_changed_dep,rustc_library)
+
+$(obj)/kernel.o: private rustc_target_flags = --extern alloc \
+ --extern macros --extern bindings
+$(obj)/kernel.o: $(src)/kernel/lib.rs $(obj)/alloc.o \
+ $(obj)/libmacros.so $(obj)/bindings.o FORCE
+ $(call if_changed_dep,rustc_library)
+
+endif # CONFIG_RUST
diff --git a/rust/bindgen_parameters b/rust/bindgen_parameters
new file mode 100644
index 000000000000..be4963bf7203
--- /dev/null
+++ b/rust/bindgen_parameters
@@ -0,0 +1,21 @@
+# SPDX-License-Identifier: GPL-2.0
+
+--opaque-type xregs_state
+--opaque-type desc_struct
+--opaque-type arch_lbr_state
+--opaque-type local_apic
+
+# Packed type cannot transitively contain a `#[repr(align)]` type.
+--opaque-type x86_msi_data
+--opaque-type x86_msi_addr_lo
+
+# `try` is a reserved keyword since Rust 2018; solved in `bindgen` v0.59.2,
+# commit 2aed6b021680 ("context: Escape the try keyword properly").
+--opaque-type kunit_try_catch
+
+# If SMP is disabled, `arch_spinlock_t` is defined as a ZST which triggers a Rust
+# warning. We don't need to peek into it anyway.
+--opaque-type spinlock
+
+# `seccomp`'s comment gets understood as a doctest
+--no-doc-comments
diff --git a/scripts/Kconfig.include b/scripts/Kconfig.include
index 0496efd6e117..83e850321eb6 100644
--- a/scripts/Kconfig.include
+++ b/scripts/Kconfig.include
@@ -36,12 +36,12 @@ ld-option = $(success,$(LD) -v $(1))
as-instr = $(success,printf "%b\n" "$(1)" | $(CC) $(CLANG_FLAGS) -c -x assembler -o /dev/null -)
# check if $(CC) and $(LD) exist
-$(error-if,$(failure,command -v $(CC)),compiler '$(CC)' not found)
+$(error-if,$(failure,command -v $(CC)),C compiler '$(CC)' not found)
$(error-if,$(failure,command -v $(LD)),linker '$(LD)' not found)
-# Get the compiler name, version, and error out if it is not supported.
+# Get the C compiler name, version, and error out if it is not supported.
cc-info := $(shell,$(srctree)/scripts/cc-version.sh $(CC))
-$(error-if,$(success,test -z "$(cc-info)"),Sorry$(comma) this compiler is not supported.)
+$(error-if,$(success,test -z "$(cc-info)"),Sorry$(comma) this C compiler is not supported.)
cc-name := $(shell,set -- $(cc-info) && echo $1)
cc-version := $(shell,set -- $(cc-info) && echo $2)
diff --git a/scripts/Makefile b/scripts/Makefile
index f084f08ed176..1575af84d557 100644
--- a/scripts/Makefile
+++ b/scripts/Makefile
@@ -10,6 +10,9 @@ hostprogs-always-$(CONFIG_BUILDTIME_TABLE_SORT) += sorttable
hostprogs-always-$(CONFIG_ASN1) += asn1_compiler
hostprogs-always-$(CONFIG_MODULE_SIG_FORMAT) += sign-file
hostprogs-always-$(CONFIG_SYSTEM_EXTRA_CERTIFICATE) += insert-sys-cert
+hostprogs-always-$(CONFIG_RUST) += generate_rust_target
+
+generate_rust_target-rust := y
HOSTCFLAGS_sorttable.o = -I$(srctree)/tools/include
HOSTLDLIBS_sorttable = -lpthread
diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index cac070aee791..ffbbeae0989b 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -26,6 +26,7 @@ EXTRA_CPPFLAGS :=
EXTRA_LDFLAGS :=
asflags-y :=
ccflags-y :=
+rustflags-y :=
cppflags-y :=
ldflags-y :=
@@ -271,6 +272,65 @@ quiet_cmd_cc_lst_c = MKLST $@
$(obj)/%.lst: $(src)/%.c FORCE
$(call if_changed_dep,cc_lst_c)
+# Compile Rust sources (.rs)
+# ---------------------------------------------------------------------------
+
+rust_allowed_features := core_ffi_c
+
+rust_common_cmd = \
+ RUST_MODFILE=$(modfile) $(RUSTC_OR_CLIPPY) $(rust_flags) \
+ -Zallow-features=$(rust_allowed_features) \
+ -Zcrate-attr=no_std \
+ -Zcrate-attr='feature($(rust_allowed_features))' \
+ --extern alloc --extern kernel \
+ --crate-type rlib --out-dir $(obj) -L $(objtree)/rust/ \
+ --crate-name $(basename $(notdir $@))
+
+rust_handle_depfile = \
+ mv $(obj)/$(basename $(notdir $@)).d $(depfile); \
+ sed -i '/^\#/d' $(depfile)
+
+# `--emit=obj`, `--emit=asm` and `--emit=llvm-ir` imply a single codegen unit
+# will be used. We explicitly request `-Ccodegen-units=1` in any case, and
+# the compiler shows a warning if it is not 1. However, if we ever stop
+# requesting it explicitly and we start using some other `--emit` that does not
+# imply it (and for which codegen is performed), then we would be out of sync,
+# i.e. the outputs we would get for the different single targets (e.g. `.ll`)
+# would not match each other.
+
+quiet_cmd_rustc_o_rs = $(RUSTC_OR_CLIPPY_QUIET) $(quiet_modtag) $@
+ cmd_rustc_o_rs = \
+ $(rust_common_cmd) --emit=dep-info,obj $<; \
+ $(rust_handle_depfile)
+
+$(obj)/%.o: $(src)/%.rs FORCE
+ $(call if_changed_dep,rustc_o_rs)
+
+quiet_cmd_rustc_rsi_rs = $(RUSTC_OR_CLIPPY_QUIET) $(quiet_modtag) $@
+ cmd_rustc_rsi_rs = \
+ $(rust_common_cmd) --emit=dep-info -Zunpretty=expanded $< >$@; \
+ command -v $(RUSTFMT) >/dev/null && $(RUSTFMT) $@; \
+ $(rust_handle_depfile)
+
+$(obj)/%.rsi: $(src)/%.rs FORCE
+ $(call if_changed_dep,rustc_rsi_rs)
+
+quiet_cmd_rustc_s_rs = $(RUSTC_OR_CLIPPY_QUIET) $(quiet_modtag) $@
+ cmd_rustc_s_rs = \
+ $(rust_common_cmd) --emit=dep-info,asm $<; \
+ $(rust_handle_depfile)
+
+$(obj)/%.s: $(src)/%.rs FORCE
+ $(call if_changed_dep,rustc_s_rs)
+
+quiet_cmd_rustc_ll_rs = $(RUSTC_OR_CLIPPY_QUIET) $(quiet_modtag) $@
+ cmd_rustc_ll_rs = \
+ $(rust_common_cmd) --emit=dep-info,llvm-ir $<; \
+ $(rust_handle_depfile)
+
+$(obj)/%.ll: $(src)/%.rs FORCE
+ $(call if_changed_dep,rustc_ll_rs)
+
# Compile assembler sources (.S)
# ---------------------------------------------------------------------------
diff --git a/scripts/Makefile.debug b/scripts/Makefile.debug
index 9f39b0130551..fe87389d52c0 100644
--- a/scripts/Makefile.debug
+++ b/scripts/Makefile.debug
@@ -1,4 +1,5 @@
DEBUG_CFLAGS :=
+DEBUG_RUSTFLAGS :=
ifdef CONFIG_DEBUG_INFO_SPLIT
DEBUG_CFLAGS += -gsplit-dwarf
@@ -10,6 +11,12 @@ ifndef CONFIG_AS_IS_LLVM
KBUILD_AFLAGS += -Wa,-gdwarf-2
endif
+ifdef CONFIG_DEBUG_INFO_REDUCED
+DEBUG_RUSTFLAGS += -Cdebuginfo=1
+else
+DEBUG_RUSTFLAGS += -Cdebuginfo=2
+endif
+
ifndef CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT
dwarf-version-$(CONFIG_DEBUG_INFO_DWARF4) := 4
dwarf-version-$(CONFIG_DEBUG_INFO_DWARF5) := 5
@@ -31,3 +38,6 @@ endif
KBUILD_CFLAGS += $(DEBUG_CFLAGS)
export DEBUG_CFLAGS
+
+KBUILD_RUSTFLAGS += $(DEBUG_RUSTFLAGS)
+export DEBUG_RUSTFLAGS
diff --git a/scripts/Makefile.host b/scripts/Makefile.host
index 278b4d6ac945..da133780b751 100644
--- a/scripts/Makefile.host
+++ b/scripts/Makefile.host
@@ -22,6 +22,8 @@ $(obj)/%.tab.c $(obj)/%.tab.h: $(src)/%.y FORCE
# to preprocess a data file.
#
# Both C and C++ are supported, but preferred language is C for such utilities.
+# Rust is also supported, but it may only be used in scenarios where a Rust
+# toolchain is required to be available (e.g. when `CONFIG_RUST` is enabled).
#
# Sample syntax (see Documentation/kbuild/makefiles.rst for reference)
# hostprogs := bin2hex
@@ -37,15 +39,20 @@ $(obj)/%.tab.c $(obj)/%.tab.h: $(src)/%.y FORCE
# qconf-objs := menu.o
# Will compile qconf as a C++ program, and menu as a C program.
# They are linked as C++ code to the executable qconf
+#
+# hostprogs := target
+# target-rust := y
+# Will compile `target` as a Rust program, using `target.rs` as the crate root.
+# The crate may consist of several source files.
# C code
# Executables compiled from a single .c file
host-csingle := $(foreach m,$(hostprogs), \
- $(if $($(m)-objs)$($(m)-cxxobjs),,$(m)))
+ $(if $($(m)-objs)$($(m)-cxxobjs)$($(m)-rust),,$(m)))
# C executables linked based on several .o files
host-cmulti := $(foreach m,$(hostprogs),\
- $(if $($(m)-cxxobjs),,$(if $($(m)-objs),$(m))))
+ $(if $($(m)-cxxobjs)$($(m)-rust),,$(if $($(m)-objs),$(m))))
# Object (.o) files compiled from .c files
host-cobjs := $(sort $(foreach m,$(hostprogs),$($(m)-objs)))
@@ -58,11 +65,17 @@ host-cxxmulti := $(foreach m,$(hostprogs),$(if $($(m)-cxxobjs),$(m)))
# C++ Object (.o) files compiled from .cc files
host-cxxobjs := $(sort $(foreach m,$(host-cxxmulti),$($(m)-cxxobjs)))
+# Rust code
+# Executables compiled from a single Rust crate (which may consist of
+# one or more .rs files)
+host-rust := $(foreach m,$(hostprogs),$(if $($(m)-rust),$(m)))
+
host-csingle := $(addprefix $(obj)/,$(host-csingle))
host-cmulti := $(addprefix $(obj)/,$(host-cmulti))
host-cobjs := $(addprefix $(obj)/,$(host-cobjs))
host-cxxmulti := $(addprefix $(obj)/,$(host-cxxmulti))
host-cxxobjs := $(addprefix $(obj)/,$(host-cxxobjs))
+host-rust := $(addprefix $(obj)/,$(host-rust))
#####
# Handle options to gcc. Support building with separate output directory
@@ -71,6 +84,8 @@ _hostc_flags = $(KBUILD_HOSTCFLAGS) $(HOST_EXTRACFLAGS) \
$(HOSTCFLAGS_$(target-stem).o)
_hostcxx_flags = $(KBUILD_HOSTCXXFLAGS) $(HOST_EXTRACXXFLAGS) \
$(HOSTCXXFLAGS_$(target-stem).o)
+_hostrust_flags = $(KBUILD_HOSTRUSTFLAGS) $(HOST_EXTRARUSTFLAGS) \
+ $(HOSTRUSTFLAGS_$(target-stem))
# $(objtree)/$(obj) for including generated headers from checkin source files
ifeq ($(KBUILD_EXTMOD),)
@@ -82,6 +97,7 @@ endif
hostc_flags = -Wp,-MMD,$(depfile) $(_hostc_flags)
hostcxx_flags = -Wp,-MMD,$(depfile) $(_hostcxx_flags)
+hostrust_flags = $(_hostrust_flags)
#####
# Compile programs on the host
@@ -128,5 +144,17 @@ quiet_cmd_host-cxxobjs = HOSTCXX $@
$(host-cxxobjs): $(obj)/%.o: $(src)/%.cc FORCE
$(call if_changed_dep,host-cxxobjs)
+# Create executable from a single Rust crate (which may consist of
+# one or more `.rs` files)
+# host-rust -> Executable
+quiet_cmd_host-rust = HOSTRUSTC $@
+ cmd_host-rust = \
+ $(HOSTRUSTC) $(hostrust_flags) --emit=dep-info,link \
+ --out-dir=$(obj)/ $<; \
+ mv $(obj)/$(target-stem).d $(depfile); \
+ sed -i '/^\#/d' $(depfile)
+$(host-rust): $(obj)/%: $(src)/%.rs FORCE
+ $(call if_changed_dep,host-rust)
+
targets += $(host-csingle) $(host-cmulti) $(host-cobjs) \
- $(host-cxxmulti) $(host-cxxobjs)
+ $(host-cxxmulti) $(host-cxxobjs) $(host-rust)
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 3fb6a99e78c4..c88b98b5dc44 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -8,6 +8,7 @@ ldflags-y += $(EXTRA_LDFLAGS)
# flags that take effect in current and sub directories
KBUILD_AFLAGS += $(subdir-asflags-y)
KBUILD_CFLAGS += $(subdir-ccflags-y)
+KBUILD_RUSTFLAGS += $(subdir-rustflags-y)
# Figure out what we need to build from the various variables
# ===========================================================================
@@ -128,6 +129,10 @@ _c_flags = $(filter-out $(CFLAGS_REMOVE_$(target-stem).o), \
$(filter-out $(ccflags-remove-y), \
$(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(ccflags-y)) \
$(CFLAGS_$(target-stem).o))
+_rust_flags = $(filter-out $(RUSTFLAGS_REMOVE_$(target-stem).o), \
+ $(filter-out $(rustflags-remove-y), \
+ $(KBUILD_RUSTFLAGS) $(rustflags-y)) \
+ $(RUSTFLAGS_$(target-stem).o))
_a_flags = $(filter-out $(AFLAGS_REMOVE_$(target-stem).o), \
$(filter-out $(asflags-remove-y), \
$(KBUILD_CPPFLAGS) $(KBUILD_AFLAGS) $(asflags-y)) \
@@ -202,6 +207,11 @@ modkern_cflags = \
$(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \
$(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL) $(modfile_flags))
+modkern_rustflags = \
+ $(if $(part-of-module), \
+ $(KBUILD_RUSTFLAGS_MODULE) $(RUSTFLAGS_MODULE), \
+ $(KBUILD_RUSTFLAGS_KERNEL) $(RUSTFLAGS_KERNEL))
+
modkern_aflags = $(if $(part-of-module), \
$(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE), \
$(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL))
@@ -211,6 +221,8 @@ c_flags = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \
$(_c_flags) $(modkern_cflags) \
$(basename_flags) $(modname_flags)
+rust_flags = $(_rust_flags) $(modkern_rustflags) @$(objtree)/include/generated/rustc_cfg
+
a_flags = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \
$(_a_flags) $(modkern_aflags)
diff --git a/scripts/Makefile.modfinal b/scripts/Makefile.modfinal
index 35100e981f4a..9a1fa6aa30fe 100644
--- a/scripts/Makefile.modfinal
+++ b/scripts/Makefile.modfinal
@@ -39,11 +39,13 @@ quiet_cmd_ld_ko_o = LD [M] $@
quiet_cmd_btf_ko = BTF [M] $@
cmd_btf_ko = \
- if [ -f vmlinux ]; then \
+ if [ ! -f vmlinux ]; then \
+ printf "Skipping BTF generation for %s due to unavailability of vmlinux\n" $@ 1>&2; \
+ elif [ -n "$(CONFIG_RUST)" ] && $(srctree)/scripts/is_rust_module.sh $@; then \
+ printf "Skipping BTF generation for %s because it's a Rust module\n" $@ 1>&2; \
+ else \
LLVM_OBJCOPY="$(OBJCOPY)" $(PAHOLE) -J $(PAHOLE_FLAGS) --btf_base vmlinux $@; \
$(RESOLVE_BTFIDS) -b vmlinux $@; \
- else \
- printf "Skipping BTF generation for %s due to unavailability of vmlinux\n" $@ 1>&2; \
fi;
# Same as newer-prereqs, but allows to exclude specified extra dependencies
diff --git a/scripts/cc-version.sh b/scripts/cc-version.sh
index f1952c522466..2401c86fcf53 100755
--- a/scripts/cc-version.sh
+++ b/scripts/cc-version.sh
@@ -1,13 +1,13 @@
#!/bin/sh
# SPDX-License-Identifier: GPL-2.0
#
-# Print the compiler name and its version in a 5 or 6-digit form.
+# Print the C compiler name and its version in a 5 or 6-digit form.
# Also, perform the minimum version check.
set -e
-# Print the compiler name and some version components.
-get_compiler_info()
+# Print the C compiler name and some version components.
+get_c_compiler_info()
{
cat <<- EOF | "$@" -E -P -x c - 2>/dev/null
#if defined(__clang__)
@@ -32,7 +32,7 @@ get_canonical_version()
# $@ instead of $1 because multiple words might be given, e.g. CC="ccache gcc".
orig_args="$@"
-set -- $(get_compiler_info "$@")
+set -- $(get_c_compiler_info "$@")
name=$1
@@ -52,7 +52,7 @@ ICC)
min_version=$($min_tool_version icc)
;;
*)
- echo "$orig_args: unknown compiler" >&2
+ echo "$orig_args: unknown C compiler" >&2
exit 1
;;
esac
@@ -62,7 +62,7 @@ min_cversion=$(get_canonical_version $min_version)
if [ "$cversion" -lt "$min_cversion" ]; then
echo >&2 "***"
- echo >&2 "*** Compiler is too old."
+ echo >&2 "*** C compiler is too old."
echo >&2 "*** Your $name version: $version"
echo >&2 "*** Minimum $name version: $min_version"
echo >&2 "***"
diff --git a/scripts/kconfig/confdata.c b/scripts/kconfig/confdata.c
index c4340c90e172..b7c9f1dd5e42 100644
--- a/scripts/kconfig/confdata.c
+++ b/scripts/kconfig/confdata.c
@@ -216,6 +216,13 @@ static const char *conf_get_autoheader_name(void)
return name ? name : "include/generated/autoconf.h";
}
+static const char *conf_get_rustccfg_name(void)
+{
+ char *name = getenv("KCONFIG_RUSTCCFG");
+
+ return name ? name : "include/generated/rustc_cfg";
+}
+
static int conf_set_sym_val(struct symbol *sym, int def, int def_flags, char *p)
{
char *p2;
@@ -605,6 +612,9 @@ static const struct comment_style comment_style_c = {
static void conf_write_heading(FILE *fp, const struct comment_style *cs)
{
+ if (!cs)
+ return;
+
fprintf(fp, "%s\n", cs->prefix);
fprintf(fp, "%s Automatically generated file; DO NOT EDIT.\n",
@@ -745,6 +755,65 @@ static void print_symbol_for_c(FILE *fp, struct symbol *sym)
free(escaped);
}
+static void print_symbol_for_rustccfg(FILE *fp, struct symbol *sym)
+{
+ const char *val;
+ const char *val_prefix = "";
+ char *val_prefixed = NULL;
+ size_t val_prefixed_len;
+ char *escaped = NULL;
+
+ if (sym->type == S_UNKNOWN)
+ return;
+
+ val = sym_get_string_value(sym);
+
+ switch (sym->type) {
+ case S_BOOLEAN:
+ case S_TRISTATE:
+ /*
+ * We do not care about disabled ones, i.e. no need for
+ * what otherwise are "comments" in other printers.
+ */
+ if (*val == 'n')
+ return;
+
+ /*
+ * To have similar functionality to the C macro `IS_ENABLED()`
+ * we provide an empty `--cfg CONFIG_X` here in both `y`
+ * and `m` cases.
+ *
+ * Then, the common `fprintf()` below will also give us
+ * a `--cfg CONFIG_X="y"` or `--cfg CONFIG_X="m"`, which can
+ * be used as the equivalent of `IS_BUILTIN()`/`IS_MODULE()`.
+ */
+ fprintf(fp, "--cfg=%s%s\n", CONFIG_, sym->name);
+ break;
+ case S_HEX:
+ if (val[0] != '0' || (val[1] != 'x' && val[1] != 'X'))
+ val_prefix = "0x";
+ break;
+ default:
+ break;
+ }
+
+ if (strlen(val_prefix) > 0) {
+ val_prefixed_len = strlen(val) + strlen(val_prefix) + 1;
+ val_prefixed = xmalloc(val_prefixed_len);
+ snprintf(val_prefixed, val_prefixed_len, "%s%s", val_prefix, val);
+ val = val_prefixed;
+ }
+
+ /* All values get escaped: the `--cfg` option only takes strings */
+ escaped = escape_string_value(val);
+ val = escaped;
+
+ fprintf(fp, "--cfg=%s%s=%s\n", CONFIG_, sym->name, val);
+
+ free(escaped);
+ free(val_prefixed);
+}
+
/*
* Write out a minimal config.
* All values that has default values are skipped as this is redundant.
@@ -1132,6 +1201,12 @@ int conf_write_autoconf(int overwrite)
if (ret)
return ret;
+ ret = __conf_write_autoconf(conf_get_rustccfg_name(),
+ print_symbol_for_rustccfg,
+ NULL);
+ if (ret)
+ return ret;
+
/*
* Create include/config/auto.conf. This must be the last step because
* Kbuild has a dependency on auto.conf and this marks the successful
diff --git a/scripts/min-tool-version.sh b/scripts/min-tool-version.sh
index 250925aab101..b6593eac5003 100755
--- a/scripts/min-tool-version.sh
+++ b/scripts/min-tool-version.sh
@@ -30,6 +30,12 @@ llvm)
echo 11.0.0
fi
;;
+rustc)
+ echo 1.62.0
+ ;;
+bindgen)
+ echo 0.56.0
+ ;;
*)
echo "$1: unknown tool" >&2
exit 1
--
2.37.1
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH v9 24/27] docs: add Rust documentation
2022-08-05 15:41 [PATCH v9 00/27] Rust support Miguel Ojeda
2022-08-05 15:42 ` [PATCH v9 23/27] Kbuild: add " Miguel Ojeda
@ 2022-08-05 15:42 ` Miguel Ojeda
1 sibling, 0 replies; 9+ messages in thread
From: Miguel Ojeda @ 2022-08-05 15:42 UTC (permalink / raw)
To: Linus Torvalds, Greg Kroah-Hartman
Cc: rust-for-linux, linux-kernel, linux-fsdevel, patches,
Jarkko Sakkinen, Miguel Ojeda, Kees Cook, Alex Gaynor,
Finn Behrens, Adam Bratschi-Kaye, Wedson Almeida Filho,
Michael Ellerman, Sven Van Asbroeck, Wu XiangCheng, Gary Guo,
Boris-Chengbiao Zhou, Yuki Okushi, Wei Liu, Daniel Xu,
Julian Merkle, Jonathan Corbet, Masahiro Yamada, Michal Marek,
Nick Desaulniers, Boqun Feng, Björn Roy Baron, linux-doc,
linux-kbuild
Most of the documentation for Rust is written within the source code
itself, as it is idiomatic for Rust projects. This applies to both
the shared infrastructure at `rust/` as well as any other Rust module
(e.g. drivers) written across the kernel.
However, these documents contain general information that does not
fit particularly well in the source code, like the Quick Start guide.
It also contains a few other small changes elsewhere in the
documentation folder.
Reviewed-by: Kees Cook <keescook@chromium.org>
Co-developed-by: Alex Gaynor <alex.gaynor@gmail.com>
Signed-off-by: Alex Gaynor <alex.gaynor@gmail.com>
Co-developed-by: Finn Behrens <me@kloenk.de>
Signed-off-by: Finn Behrens <me@kloenk.de>
Co-developed-by: Adam Bratschi-Kaye <ark.email@gmail.com>
Signed-off-by: Adam Bratschi-Kaye <ark.email@gmail.com>
Co-developed-by: Wedson Almeida Filho <wedsonaf@google.com>
Signed-off-by: Wedson Almeida Filho <wedsonaf@google.com>
Co-developed-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Co-developed-by: Sven Van Asbroeck <thesven73@gmail.com>
Signed-off-by: Sven Van Asbroeck <thesven73@gmail.com>
Co-developed-by: Wu XiangCheng <bobwxc@email.cn>
Signed-off-by: Wu XiangCheng <bobwxc@email.cn>
Co-developed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Gary Guo <gary@garyguo.net>
Co-developed-by: Boris-Chengbiao Zhou <bobo1239@web.de>
Signed-off-by: Boris-Chengbiao Zhou <bobo1239@web.de>
Co-developed-by: Yuki Okushi <jtitor@2k36.org>
Signed-off-by: Yuki Okushi <jtitor@2k36.org>
Co-developed-by: Wei Liu <wei.liu@kernel.org>
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Co-developed-by: Daniel Xu <dxu@dxuuu.xyz>
Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
Co-developed-by: Julian Merkle <me@jvmerkle.de>
Signed-off-by: Julian Merkle <me@jvmerkle.de>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
Documentation/doc-guide/kernel-doc.rst | 3 +
Documentation/index.rst | 1 +
Documentation/kbuild/kbuild.rst | 17 ++
Documentation/kbuild/makefiles.rst | 50 ++++-
Documentation/process/changes.rst | 41 ++++
Documentation/rust/arch-support.rst | 18 ++
Documentation/rust/coding-guidelines.rst | 216 +++++++++++++++++++
Documentation/rust/general-information.rst | 79 +++++++
Documentation/rust/index.rst | 22 ++
Documentation/rust/quick-start.rst | 232 +++++++++++++++++++++
10 files changed, 675 insertions(+), 4 deletions(-)
create mode 100644 Documentation/rust/arch-support.rst
create mode 100644 Documentation/rust/coding-guidelines.rst
create mode 100644 Documentation/rust/general-information.rst
create mode 100644 Documentation/rust/index.rst
create mode 100644 Documentation/rust/quick-start.rst
diff --git a/Documentation/doc-guide/kernel-doc.rst b/Documentation/doc-guide/kernel-doc.rst
index a7cb2afd7990..9b868d9eb20f 100644
--- a/Documentation/doc-guide/kernel-doc.rst
+++ b/Documentation/doc-guide/kernel-doc.rst
@@ -12,6 +12,9 @@ when it is embedded in source files.
reasons. The kernel source contains tens of thousands of kernel-doc
comments. Please stick to the style described here.
+.. note:: kernel-doc does not cover Rust code: please see
+ Documentation/rust/general-information.rst instead.
+
The kernel-doc structure is extracted from the comments, and proper
`Sphinx C Domain`_ function and type descriptions with anchors are
generated from them. The descriptions are filtered for special kernel-doc
diff --git a/Documentation/index.rst b/Documentation/index.rst
index 67036a05b771..35d90903242a 100644
--- a/Documentation/index.rst
+++ b/Documentation/index.rst
@@ -82,6 +82,7 @@ merged much easier.
maintainer/index
fault-injection/index
livepatch/index
+ rust/index
Kernel API documentation
diff --git a/Documentation/kbuild/kbuild.rst b/Documentation/kbuild/kbuild.rst
index ef19b9c13523..08f575e6236c 100644
--- a/Documentation/kbuild/kbuild.rst
+++ b/Documentation/kbuild/kbuild.rst
@@ -48,6 +48,10 @@ KCFLAGS
-------
Additional options to the C compiler (for built-in and modules).
+KRUSTFLAGS
+----------
+Additional options to the Rust compiler (for built-in and modules).
+
CFLAGS_KERNEL
-------------
Additional options for $(CC) when used to compile
@@ -57,6 +61,15 @@ CFLAGS_MODULE
-------------
Additional module specific options to use for $(CC).
+RUSTFLAGS_KERNEL
+----------------
+Additional options for $(RUSTC) when used to compile
+code that is compiled as built-in.
+
+RUSTFLAGS_MODULE
+----------------
+Additional module specific options to use for $(RUSTC).
+
LDFLAGS_MODULE
--------------
Additional options used for $(LD) when linking modules.
@@ -69,6 +82,10 @@ HOSTCXXFLAGS
------------
Additional flags to be passed to $(HOSTCXX) when building host programs.
+HOSTRUSTFLAGS
+-------------
+Additional flags to be passed to $(HOSTRUSTC) when building host programs.
+
HOSTLDFLAGS
-----------
Additional flags to be passed when linking host programs.
diff --git a/Documentation/kbuild/makefiles.rst b/Documentation/kbuild/makefiles.rst
index 11a296e52d68..5ea1e72d89c8 100644
--- a/Documentation/kbuild/makefiles.rst
+++ b/Documentation/kbuild/makefiles.rst
@@ -29,8 +29,9 @@ This document describes the Linux kernel Makefiles.
--- 4.1 Simple Host Program
--- 4.2 Composite Host Programs
--- 4.3 Using C++ for host programs
- --- 4.4 Controlling compiler options for host programs
- --- 4.5 When host programs are actually built
+ --- 4.4 Using Rust for host programs
+ --- 4.5 Controlling compiler options for host programs
+ --- 4.6 When host programs are actually built
=== 5 Userspace Program support
--- 5.1 Simple Userspace Program
@@ -835,7 +836,24 @@ Both possibilities are described in the following.
qconf-cxxobjs := qconf.o
qconf-objs := check.o
-4.4 Controlling compiler options for host programs
+4.4 Using Rust for host programs
+--------------------------------
+
+ Kbuild offers support for host programs written in Rust. However,
+ since a Rust toolchain is not mandatory for kernel compilation,
+ it may only be used in scenarios where Rust is required to be
+ available (e.g. when ``CONFIG_RUST`` is enabled).
+
+ Example::
+
+ hostprogs := target
+ target-rust := y
+
+ Kbuild will compile ``target`` using ``target.rs`` as the crate root,
+ located in the same directory as the ``Makefile``. The crate may
+ consist of several source files (see ``samples/rust/hostprogs``).
+
+4.5 Controlling compiler options for host programs
--------------------------------------------------
When compiling host programs, it is possible to set specific flags.
@@ -867,7 +885,7 @@ Both possibilities are described in the following.
When linking qconf, it will be passed the extra option
"-L$(QTDIR)/lib".
-4.5 When host programs are actually built
+4.6 When host programs are actually built
-----------------------------------------
Kbuild will only build host-programs when they are referenced
@@ -1181,6 +1199,17 @@ When kbuild executes, the following steps are followed (roughly):
The first example utilises the trick that a config option expands
to 'y' when selected.
+ KBUILD_RUSTFLAGS
+ $(RUSTC) compiler flags
+
+ Default value - see top level Makefile
+ Append or modify as required per architecture.
+
+ Often, the KBUILD_RUSTFLAGS variable depends on the configuration.
+
+ Note that target specification file generation (for ``--target``)
+ is handled in ``scripts/generate_rust_target.rs``.
+
KBUILD_AFLAGS_KERNEL
Assembler options specific for built-in
@@ -1208,6 +1237,19 @@ When kbuild executes, the following steps are followed (roughly):
are used for $(CC).
From commandline CFLAGS_MODULE shall be used (see kbuild.rst).
+ KBUILD_RUSTFLAGS_KERNEL
+ $(RUSTC) options specific for built-in
+
+ $(KBUILD_RUSTFLAGS_KERNEL) contains extra Rust compiler flags used to
+ compile resident kernel code.
+
+ KBUILD_RUSTFLAGS_MODULE
+ Options for $(RUSTC) when building modules
+
+ $(KBUILD_RUSTFLAGS_MODULE) is used to add arch-specific options that
+ are used for $(RUSTC).
+ From commandline RUSTFLAGS_MODULE shall be used (see kbuild.rst).
+
KBUILD_LDFLAGS_MODULE
Options for $(LD) when linking modules
diff --git a/Documentation/process/changes.rst b/Documentation/process/changes.rst
index 19c286c23786..9a90197989dd 100644
--- a/Documentation/process/changes.rst
+++ b/Documentation/process/changes.rst
@@ -31,6 +31,8 @@ you probably needn't concern yourself with pcmciautils.
====================== =============== ========================================
GNU C 5.1 gcc --version
Clang/LLVM (optional) 11.0.0 clang --version
+Rust (optional) 1.62.0 rustc --version
+bindgen (optional) 0.56.0 bindgen --version
GNU make 3.81 make --version
bash 4.2 bash --version
binutils 2.23 ld -v
@@ -80,6 +82,29 @@ kernels. Older releases aren't guaranteed to work, and we may drop workarounds
from the kernel that were used to support older versions. Please see additional
docs on :ref:`Building Linux with Clang/LLVM <kbuild_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.
+
+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
+be detected.
+
+bindgen (optional)
+------------------
+
+``bindgen`` is used to generate the Rust bindings to the C side of the kernel.
+It depends on ``libclang``.
+
Make
----
@@ -348,6 +373,12 @@ Sphinx
Please see :ref:`sphinx_install` in :ref:`Documentation/doc-guide/sphinx.rst <sphinxdoc>`
for details about Sphinx requirements.
+rustdoc
+-------
+
+``rustdoc`` is used to generate the documentation for Rust code. Please see
+Documentation/rust/general-information.rst for more information.
+
Getting updated software
========================
@@ -364,6 +395,16 @@ Clang/LLVM
- :ref:`Getting LLVM <getting_llvm>`.
+Rust
+----
+
+- Documentation/rust/quick-start.rst.
+
+bindgen
+-------
+
+- Documentation/rust/quick-start.rst.
+
Make
----
diff --git a/Documentation/rust/arch-support.rst b/Documentation/rust/arch-support.rst
new file mode 100644
index 000000000000..1152e0fbdad0
--- /dev/null
+++ b/Documentation/rust/arch-support.rst
@@ -0,0 +1,18 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+Arch Support
+============
+
+Currently, the Rust compiler (``rustc``) uses LLVM for code generation,
+which limits the supported architectures that can be targeted. In addition,
+support for building the kernel with LLVM/Clang varies (please see
+Documentation/kbuild/llvm.rst). This support is needed for ``bindgen``
+which uses ``libclang``.
+
+Below is a general summary of architectures that currently work. Level of
+support corresponds to ``S`` values in the ``MAINTAINERS`` file.
+
+============ ================ ==============================================
+Architecture Level of support Constraints
+============ ================ ==============================================
+============ ================ ==============================================
diff --git a/Documentation/rust/coding-guidelines.rst b/Documentation/rust/coding-guidelines.rst
new file mode 100644
index 000000000000..aa8ed082613e
--- /dev/null
+++ b/Documentation/rust/coding-guidelines.rst
@@ -0,0 +1,216 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+Coding Guidelines
+=================
+
+This document describes how to write Rust code in the kernel.
+
+
+Style & formatting
+------------------
+
+The code should be formatted using ``rustfmt``. In this way, a person
+contributing from time to time to the kernel does not need to learn and
+remember one more style guide. More importantly, reviewers and maintainers
+do not need to spend time pointing out style issues anymore, and thus
+less patch roundtrips may be needed to land a change.
+
+.. note:: Conventions on comments and documentation are not checked by
+ ``rustfmt``. Thus those are still needed to be taken care of.
+
+The default settings of ``rustfmt`` are used. This means the idiomatic Rust
+style is followed. For instance, 4 spaces are used for indentation rather
+than tabs.
+
+It is convenient to instruct editors/IDEs to format while typing,
+when saving or at commit time. However, if for some reason reformatting
+the entire kernel Rust sources is needed at some point, the following can be
+run::
+
+ make LLVM=1 rustfmt
+
+It is also possible to check if everything is formatted (printing a diff
+otherwise), for instance for a CI, with::
+
+ make LLVM=1 rustfmtcheck
+
+Like ``clang-format`` for the rest of the kernel, ``rustfmt`` works on
+individual files, and does not require a kernel configuration. Sometimes it may
+even work with broken code.
+
+
+Comments
+--------
+
+"Normal" comments (i.e. ``//``, rather than code documentation which starts
+with ``///`` or ``//!``) are written in Markdown the same way as documentation
+comments are, even though they will not be rendered. This improves consistency,
+simplifies the rules and allows to move content between the two kinds of
+comments more easily. For instance:
+
+.. code-block:: rust
+
+ // `object` is ready to be handled now.
+ f(object);
+
+Furthermore, just like documentation, comments are capitalized at the beginning
+of a sentence and ended with a period (even if it is a single sentence). This
+includes ``// SAFETY:``, ``// TODO:`` and other "tagged" comments, e.g.:
+
+.. code-block:: rust
+
+ // FIXME: The error should be handled properly.
+
+Comments should not be used for documentation purposes: comments are intended
+for implementation details, not users. This distinction is useful even if the
+reader of the source file is both an implementor and a user of an API. In fact,
+sometimes it is useful to use both comments and documentation at the same time.
+For instance, for a ``TODO`` list or to comment on the documentation itself.
+For the latter case, comments can be inserted in the middle; that is, closer to
+the line of documentation to be commented. For any other case, comments are
+written after the documentation, e.g.:
+
+.. code-block:: rust
+
+ /// Returns a new [`Foo`].
+ ///
+ /// # Examples
+ ///
+ // TODO: Find a better example.
+ /// ```
+ /// let foo = f(42);
+ /// ```
+ // FIXME: Use fallible approach.
+ pub fn f(x: i32) -> Foo {
+ // ...
+ }
+
+One special kind of comments are the ``// SAFETY:`` comments. These must appear
+before every ``unsafe`` block, and they explain why the code inside the block is
+correct/sound, i.e. why it cannot trigger undefined behavior in any case, e.g.:
+
+.. code-block:: rust
+
+ // SAFETY: `p` is valid by the safety requirements.
+ unsafe { *p = 0; }
+
+``// SAFETY:`` comments are not to be confused with the ``# Safety`` sections
+in code documentation. ``# Safety`` sections specify the contract that callers
+(for functions) or implementors (for traits) need to abide by. ``// SAFETY:``
+comments show why a call (for functions) or implementation (for traits) actually
+respects the preconditions stated in a ``# Safety`` section or the language
+reference.
+
+
+Code documentation
+------------------
+
+Rust kernel code is not documented like C kernel code (i.e. via kernel-doc).
+Instead, the usual system for documenting Rust code is used: the ``rustdoc``
+tool, which uses Markdown (a lightweight markup language).
+
+To learn Markdown, there are many guides available out there. For instance,
+the one at:
+
+ https://commonmark.org/help/
+
+This is how a well-documented Rust function may look like:
+
+.. code-block:: rust
+
+ /// Returns the contained [`Some`] value, consuming the `self` value,
+ /// without checking that the value is not [`None`].
+ ///
+ /// # Safety
+ ///
+ /// Calling this method on [`None`] is *[undefined behavior]*.
+ ///
+ /// [undefined behavior]: https://doc.rust-lang.org/reference/behavior-considered-undefined.html
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// let x = Some("air");
+ /// assert_eq!(unsafe { x.unwrap_unchecked() }, "air");
+ /// ```
+ pub unsafe fn unwrap_unchecked(self) -> T {
+ match self {
+ Some(val) => val,
+
+ // SAFETY: The safety contract must be upheld by the caller.
+ None => unsafe { hint::unreachable_unchecked() },
+ }
+ }
+
+This example showcases a few ``rustdoc`` features and some conventions followed
+in the kernel:
+
+ - The first paragraph must be a single sentence briefly describing what
+ the documented item does. Further explanations must go in extra paragraphs.
+
+ - Unsafe functions must document their safety preconditions under
+ a ``# Safety`` section.
+
+ - While not shown here, if a function may panic, the conditions under which
+ that happens must be described under a ``# Panics`` section.
+
+ Please note that panicking should be very rare and used only with a good
+ reason. In almost all cases, a fallible approach should be used, typically
+ returning a ``Result``.
+
+ - If providing examples of usage would help readers, they must be written in
+ a section called ``# Examples``.
+
+ - Rust items (functions, types, constants...) must be linked appropriately
+ (``rustdoc`` will create a link automatically).
+
+ - Any ``unsafe`` block must be preceded by a ``// SAFETY:`` comment
+ describing why the code inside is sound.
+
+ While sometimes the reason might look trivial and therefore unneeded,
+ writing these comments is not just a good way of documenting what has been
+ taken into account, but most importantly, it provides a way to know that
+ there are no *extra* implicit constraints.
+
+To learn more about how to write documentation for Rust and extra features,
+please take a look at the ``rustdoc`` book at:
+
+ https://doc.rust-lang.org/rustdoc/how-to-write-documentation.html
+
+
+Naming
+------
+
+Rust kernel code follows the usual Rust naming conventions:
+
+ https://rust-lang.github.io/api-guidelines/naming.html
+
+When existing C concepts (e.g. macros, functions, objects...) are wrapped into
+a Rust abstraction, a name as close as reasonably possible to the C side should
+be used in order to avoid confusion and to improve readability when switching
+back and forth between the C and Rust sides. For instance, macros such as
+``pr_info`` from C are named the same in the Rust side.
+
+Having said that, casing should be adjusted to follow the Rust naming
+conventions, and namespacing introduced by modules and types should not be
+repeated in the item names. For instance, when wrapping constants like:
+
+.. code-block:: c
+
+ #define GPIO_LINE_DIRECTION_IN 0
+ #define GPIO_LINE_DIRECTION_OUT 1
+
+The equivalent in Rust may look like (ignoring documentation):
+
+.. code-block:: rust
+
+ pub mod gpio {
+ pub enum LineDirection {
+ In = bindings::GPIO_LINE_DIRECTION_IN as _,
+ Out = bindings::GPIO_LINE_DIRECTION_OUT as _,
+ }
+ }
+
+That is, the equivalent of ``GPIO_LINE_DIRECTION_IN`` would be referred to as
+``gpio::LineDirection::In``. In particular, it should not be named
+``gpio::gpio_line_direction::GPIO_LINE_DIRECTION_IN``.
diff --git a/Documentation/rust/general-information.rst b/Documentation/rust/general-information.rst
new file mode 100644
index 000000000000..49029ee82e55
--- /dev/null
+++ b/Documentation/rust/general-information.rst
@@ -0,0 +1,79 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+General Information
+===================
+
+This document contains useful information to know when working with
+the Rust support in the kernel.
+
+
+Code documentation
+------------------
+
+Rust kernel code is documented using ``rustdoc``, its built-in documentation
+generator.
+
+The generated HTML docs include integrated search, linked items (e.g. types,
+functions, constants), source code, etc. They may be read at (TODO: link when
+in mainline and generated alongside the rest of the documentation):
+
+ http://kernel.org/
+
+The docs can also be easily generated and read locally. This is quite fast
+(same order as compiling the code itself) and no special tools or environment
+are needed. This has the added advantage that they will be tailored to
+the particular kernel configuration used. To generate them, use the ``rustdoc``
+target with the same invocation used for compilation, e.g.::
+
+ make LLVM=1 rustdoc
+
+To read the docs locally in your web browser, run e.g.::
+
+ xdg-open rust/doc/kernel/index.html
+
+To learn about how to write the documentation, please see coding-guidelines.rst.
+
+
+Extra lints
+-----------
+
+While ``rustc`` is a very helpful compiler, some extra lints and analyses are
+available via ``clippy``, a Rust linter. To enable it, pass ``CLIPPY=1`` to
+the same invocation used for compilation, e.g.::
+
+ make LLVM=1 CLIPPY=1
+
+Please note that Clippy may change code generation, thus it should not be
+enabled while building a production kernel.
+
+
+Abstractions vs. bindings
+-------------------------
+
+Abstractions are Rust code wrapping kernel functionality from the C side.
+
+In order to use functions and types from the C side, bindings are created.
+Bindings are the declarations for Rust of those functions and types from
+the C side.
+
+For instance, one may write a ``Mutex`` abstraction in Rust which wraps
+a ``struct mutex`` from the C side and calls its functions through the bindings.
+
+Abstractions are not available for all the kernel internal APIs and concepts,
+but it is intended that coverage is expanded as time goes on. "Leaf" modules
+(e.g. drivers) should not use the C bindings directly. Instead, subsystems
+should provide as-safe-as-possible abstractions as needed.
+
+
+Conditional compilation
+-----------------------
+
+Rust code has access to conditional compilation based on the kernel
+configuration:
+
+.. code-block:: rust
+
+ #[cfg(CONFIG_X)] // Enabled (`y` or `m`)
+ #[cfg(CONFIG_X="y")] // Enabled as a built-in (`y`)
+ #[cfg(CONFIG_X="m")] // Enabled as a module (`m`)
+ #[cfg(not(CONFIG_X))] // Disabled
diff --git a/Documentation/rust/index.rst b/Documentation/rust/index.rst
new file mode 100644
index 000000000000..4ae8c66b94fa
--- /dev/null
+++ b/Documentation/rust/index.rst
@@ -0,0 +1,22 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+Rust
+====
+
+Documentation related to Rust within the kernel. To start using Rust
+in the kernel, please read the quick-start.rst guide.
+
+.. toctree::
+ :maxdepth: 1
+
+ quick-start
+ general-information
+ coding-guidelines
+ arch-support
+
+.. only:: subproject and html
+
+ Indices
+ =======
+
+ * :ref:`genindex`
diff --git a/Documentation/rust/quick-start.rst b/Documentation/rust/quick-start.rst
new file mode 100644
index 000000000000..13b7744b1e27
--- /dev/null
+++ b/Documentation/rust/quick-start.rst
@@ -0,0 +1,232 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+Quick Start
+===========
+
+This document describes how to get started with kernel development in Rust.
+
+
+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.
+
+To easily check whether the requirements are met, the following target
+can be used::
+
+ make LLVM=1 rustavailable
+
+This triggers the same logic used by Kconfig to determine whether
+``RUST_IS_AVAILABLE`` should be enabled; but it also explains why not
+if that is the case.
+
+
+rustc
+*****
+
+A particular version of the Rust compiler is required. Newer versions may or
+may not work because, for the moment, the kernel depends on some unstable
+Rust features.
+
+If ``rustup`` is being used, enter the checked out source code directory
+and run::
+
+ rustup override set $(scripts/min-tool-version.sh rustc)
+
+Otherwise, fetch a standalone installer or install ``rustup`` from:
+
+ https://www.rust-lang.org
+
+
+Rust standard library source
+****************************
+
+The Rust standard library source is required because the build system will
+cross-compile ``core`` and ``alloc``.
+
+If ``rustup`` is being used, run::
+
+ rustup component add rust-src
+
+The components are installed per toolchain, thus upgrading the Rust compiler
+version later on requires re-adding the component.
+
+Otherwise, if a standalone installer is used, the Rust repository may be cloned
+into the installation folder of the toolchain::
+
+ git clone --recurse-submodules \
+ --branch $(scripts/min-tool-version.sh rustc) \
+ https://github.com/rust-lang/rust \
+ $(rustc --print sysroot)/lib/rustlib/src/rust
+
+In this case, upgrading the Rust compiler version later on requires manually
+updating this clone.
+
+
+libclang
+********
+
+``libclang`` (part of LLVM) is used by ``bindgen`` to understand the C code
+in the kernel, which means LLVM needs to be installed; like when the kernel
+is compiled with ``CC=clang`` or ``LLVM=1``.
+
+Linux distributions are likely to have a suitable one available, so it is
+best to check that first.
+
+There are also some binaries for several systems and architectures uploaded at:
+
+ https://releases.llvm.org/download.html
+
+Otherwise, building LLVM takes quite a while, but it is not a complex process:
+
+ https://llvm.org/docs/GettingStarted.html#getting-the-source-code-and-building-llvm
+
+Please see Documentation/kbuild/llvm.rst for more information and further ways
+to fetch pre-built releases and distribution packages.
+
+
+bindgen
+*******
+
+The bindings to the C side of the kernel are generated at build time using
+the ``bindgen`` tool. A particular version is required.
+
+Install it via (note that this will download and build the tool from source)::
+
+ cargo install --locked --version $(scripts/min-tool-version.sh bindgen) bindgen
+
+
+Requirements: Developing
+------------------------
+
+This section explains how to fetch the tools needed for developing. That is,
+they are not needed when just building the kernel.
+
+
+rustfmt
+*******
+
+The ``rustfmt`` tool is used to automatically format all the Rust kernel code,
+including the generated C bindings (for details, please see
+coding-guidelines.rst).
+
+If ``rustup`` is being used, its ``default`` profile already installs the tool,
+thus nothing needs to be done. If another profile is being used, the component
+can be installed manually::
+
+ rustup component add rustfmt
+
+The standalone installers also come with ``rustfmt``.
+
+
+clippy
+******
+
+``clippy`` is a Rust linter. Running it provides extra warnings for Rust code.
+It can be run by passing ``CLIPPY=1`` to ``make`` (for details, please see
+general-information.rst).
+
+If ``rustup`` is being used, its ``default`` profile already installs the tool,
+thus nothing needs to be done. If another profile is being used, the component
+can be installed manually::
+
+ rustup component add clippy
+
+The standalone installers also come with ``clippy``.
+
+
+cargo
+*****
+
+``cargo`` is the Rust native build system. It is currently required to run
+the tests since it is used to build a custom standard library that contains
+the facilities provided by the custom ``alloc`` in the kernel. The tests can
+be run using the ``rusttest`` Make target.
+
+If ``rustup`` is being used, all the profiles already install the tool,
+thus nothing needs to be done.
+
+The standalone installers also come with ``cargo``.
+
+
+rustdoc
+*******
+
+``rustdoc`` is the documentation tool for Rust. It generates pretty HTML
+documentation for Rust code (for details, please see
+general-information.rst).
+
+``rustdoc`` is also used to test the examples provided in documented Rust code
+(called doctests or documentation tests). The ``rusttest`` Make target uses
+this feature.
+
+If ``rustup`` is being used, all the profiles already install the tool,
+thus nothing needs to be done.
+
+The standalone installers also come with ``rustdoc``.
+
+
+rust-analyzer
+*************
+
+The `rust-analyzer <https://rust-analyzer.github.io/>`_ language server can
+be used with many editors to enable syntax highlighting, completion, go to
+definition, and other features.
+
+``rust-analyzer`` needs a configuration file, ``rust-project.json``, which
+can be generated by the ``rust-analyzer`` Make target.
+
+
+Configuration
+-------------
+
+``Rust support`` (``CONFIG_RUST``) needs to be enabled in the ``General setup``
+menu. The option is only shown if a suitable Rust toolchain is found (see
+above), as long as the other requirements are met. In turn, this will make
+visible the rest of options that depend on Rust.
+
+Afterwards, go to::
+
+ Kernel hacking
+ -> Sample kernel code
+ -> Rust samples
+
+And enable some sample modules either as built-in or as loadable.
+
+
+Building
+--------
+
+Building a kernel with a complete LLVM toolchain is the best supported setup
+at the moment. That is::
+
+ make LLVM=1
+
+For architectures that do not support a full LLVM toolchain, use::
+
+ make CC=clang
+
+Using GCC also works for some configurations, but it is very experimental at
+the moment.
+
+
+Hacking
+-------
+
+To dive deeper, take a look at the source code of the samples
+at ``samples/rust/``, the Rust support code under ``rust/`` and
+the ``Rust hacking`` menu under ``Kernel hacking``.
+
+If GDB/Binutils is used and Rust symbols are not getting demangled, the reason
+is the toolchain does not support Rust's new v0 mangling scheme yet.
+There are a few ways out:
+
+ - Install a newer release (GDB >= 10.2, Binutils >= 2.36).
+
+ - Some versions of GDB (e.g. vanilla GDB 10.1) are able to use
+ the pre-demangled names embedded in the debug info (``CONFIG_DEBUG_INFO``).
--
2.37.1
^ permalink raw reply related [flat|nested] 9+ messages in thread
* Re: [PATCH v9 23/27] Kbuild: add Rust support
2022-08-05 15:42 ` [PATCH v9 23/27] Kbuild: add " Miguel Ojeda
@ 2022-08-17 20:26 ` Kees Cook
2022-08-17 20:56 ` Miguel Ojeda
2022-08-22 22:35 ` Nick Desaulniers
2022-09-12 16:07 ` Masahiro Yamada
2 siblings, 1 reply; 9+ messages in thread
From: Kees Cook @ 2022-08-17 20:26 UTC (permalink / raw)
To: Miguel Ojeda
Cc: Linus Torvalds, Greg Kroah-Hartman, rust-for-linux, linux-kernel,
linux-fsdevel, patches, Jarkko Sakkinen, Alex Gaynor,
Finn Behrens, Adam Bratschi-Kaye, Wedson Almeida Filho,
Michael Ellerman, Sven Van Asbroeck, Gary Guo,
Boris-Chengbiao Zhou, Boqun Feng, Douglas Su, Dariusz Sosnowski,
Antonio Terceiro, Daniel Xu, Björn Roy Baron,
Martin Rodriguez Reboredo, Masahiro Yamada, Michal Marek,
Nick Desaulniers, linux-kbuild
On Fri, Aug 05, 2022 at 05:42:08PM +0200, Miguel Ojeda wrote:
> Having most of the new files in place, we now enable Rust support
> in the build system, including `Kconfig` entries related to Rust,
> the Rust configuration printer and a few other bits.
>
> Co-developed-by: Alex Gaynor <alex.gaynor@gmail.com>
> Signed-off-by: Alex Gaynor <alex.gaynor@gmail.com>
> Co-developed-by: Finn Behrens <me@kloenk.de>
> Signed-off-by: Finn Behrens <me@kloenk.de>
> Co-developed-by: Adam Bratschi-Kaye <ark.email@gmail.com>
> Signed-off-by: Adam Bratschi-Kaye <ark.email@gmail.com>
> Co-developed-by: Wedson Almeida Filho <wedsonaf@google.com>
> Signed-off-by: Wedson Almeida Filho <wedsonaf@google.com>
> Co-developed-by: Michael Ellerman <mpe@ellerman.id.au>
> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
> Co-developed-by: Sven Van Asbroeck <thesven73@gmail.com>
> Signed-off-by: Sven Van Asbroeck <thesven73@gmail.com>
> Co-developed-by: Gary Guo <gary@garyguo.net>
> Signed-off-by: Gary Guo <gary@garyguo.net>
> Co-developed-by: Boris-Chengbiao Zhou <bobo1239@web.de>
> Signed-off-by: Boris-Chengbiao Zhou <bobo1239@web.de>
> Co-developed-by: Boqun Feng <boqun.feng@gmail.com>
> Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
> Co-developed-by: Douglas Su <d0u9.su@outlook.com>
> Signed-off-by: Douglas Su <d0u9.su@outlook.com>
> Co-developed-by: Dariusz Sosnowski <dsosnowski@dsosnowski.pl>
> Signed-off-by: Dariusz Sosnowski <dsosnowski@dsosnowski.pl>
> Co-developed-by: Antonio Terceiro <antonio.terceiro@linaro.org>
> Signed-off-by: Antonio Terceiro <antonio.terceiro@linaro.org>
> Co-developed-by: Daniel Xu <dxu@dxuuu.xyz>
> Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
> Co-developed-by: Björn Roy Baron <bjorn3_gh@protonmail.com>
> Signed-off-by: Björn Roy Baron <bjorn3_gh@protonmail.com>
> Co-developed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
> Signed-off-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
> Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
It'd be nice to split this up into maybe per-target patches, but given
how long this has been getting developed, I'd prefer to avoid blocking
on that, and just get this series landed so we can move to incremental
fixes/additions.
Reviewed-by: Kees Cook <keescook@chromium.org>
-Kees
--
Kees Cook
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH v9 23/27] Kbuild: add Rust support
2022-08-17 20:26 ` Kees Cook
@ 2022-08-17 20:56 ` Miguel Ojeda
0 siblings, 0 replies; 9+ messages in thread
From: Miguel Ojeda @ 2022-08-17 20:56 UTC (permalink / raw)
To: Kees Cook
Cc: Miguel Ojeda, Linus Torvalds, Greg Kroah-Hartman, rust-for-linux,
linux-kernel, linux-fsdevel, patches, Jarkko Sakkinen,
Alex Gaynor, Finn Behrens, Adam Bratschi-Kaye,
Wedson Almeida Filho, Michael Ellerman, Sven Van Asbroeck,
Gary Guo, Boris-Chengbiao Zhou, Boqun Feng, Douglas Su,
Dariusz Sosnowski, Antonio Terceiro, Daniel Xu,
Björn Roy Baron, Martin Rodriguez Reboredo, Masahiro Yamada,
Michal Marek, Nick Desaulniers, linux-kbuild
On Wed, Aug 17, 2022 at 10:26 PM Kees Cook <keescook@chromium.org> wrote:
>
> It'd be nice to split this up into maybe per-target patches, but given
> how long this has been getting developed, I'd prefer to avoid blocking
> on that, and just get this series landed so we can move to incremental
> fixes/additions.
When I started the series, I considered several approaches, and in the
end opted for "setup as much as possible before the flag-patch that
enables the Kbuild support", which was simple, though indeed the
Kbuild patch remained fairly big.
Then some people commented on that patch over several versions, so I
kept the simple strategy :)
What I can look into is moving the optional targets out of this patch,
putting them after the "flag-patch", since they may be considered
"additional features" anyway. In fact, for the trimming down in v9, I
thought about removing them entirely. It will not change things too
much, since they are small, but it may help.
For v9 I nevertheless attempted to simplify this patch by doing the
"move all new, big files to their own patch" (see my reply at [1]), so
it is fairly smaller than in previous versions.
[1] https://lore.kernel.org/lkml/CANiq72nzOQSd2vsh2_=0YpGNpY=7agokbgi_vBc5_GF4-02rsA@mail.gmail.com/
Cheers,
Miguel
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH v9 23/27] Kbuild: add Rust support
2022-08-05 15:42 ` [PATCH v9 23/27] Kbuild: add " Miguel Ojeda
2022-08-17 20:26 ` Kees Cook
@ 2022-08-22 22:35 ` Nick Desaulniers
2022-09-12 16:07 ` Masahiro Yamada
2 siblings, 0 replies; 9+ messages in thread
From: Nick Desaulniers @ 2022-08-22 22:35 UTC (permalink / raw)
To: Miguel Ojeda, Linus Torvalds, Masahiro Yamada
Cc: Greg Kroah-Hartman, rust-for-linux, linux-kernel, linux-fsdevel,
patches, Jarkko Sakkinen, Alex Gaynor, Finn Behrens,
Adam Bratschi-Kaye, Wedson Almeida Filho, Michael Ellerman,
Sven Van Asbroeck, Gary Guo, Boris-Chengbiao Zhou, Boqun Feng,
Douglas Su, Dariusz Sosnowski, Antonio Terceiro, Daniel Xu,
Björn Roy Baron, Martin Rodriguez Reboredo, Michal Marek,
linux-kbuild
On Fri, Aug 5, 2022 at 8:44 AM Miguel Ojeda <ojeda@kernel.org> wrote:
>
> Having most of the new files in place, we now enable Rust support
> in the build system, including `Kconfig` entries related to Rust,
> the Rust configuration printer and a few other bits.
Cool, I'm finally happy with this patch.
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
I built and boot tested with CONFIG_RUST enabled, played with
CLIPPY=1, and built all of the new make targets for rust.
Thanks for all of the work that went into these series from all of the
authors and Miguel for your determination. Keep it up!
I've left comments on other patches (and I will leave one on
rust/compiler_builtins.rs because I still don't like that approach)
and there may be small cleanups we can do here or there, but I think
we're in good shape to land something and start iterating on it
upstream. I'll file bugs in your issue tracker for small nits I come
across, but so far, it's been more-so questions.
---
LWN recently demonstrated that most fixes are in relatively younger
code: https://lwn.net/Articles/902854/
An analysis of 0day exploits found in the wild in 2021 showed that for
Android, researchers are attacking drivers:
https://googleprojectzero.blogspot.com/2022/04/the-more-you-know-more-you-know-you.html
Multiple independent reports cite high numbers (70% or more) of memory
safety issues in native code:
https://www.memorysafety.org/docs/memory-safety/
I have colleagues that are developing a microkernel (they then use a
memory unsafe language for their kernel as well :^P ) to move as much
functionality as possible into lower levels of privilege. It's
interesting and I wish them well, but I also prefer more incremental
approaches to existing solutions, and suspect the way of the monolith
to still give us the best performance.
I learned an interesting word the other day: Corten Steel
from the YouTube channel Practical Engineering (it's a great channel
on Civil Engineering):
https://www.youtube.com/watch?v=2RbiCOFffRs&t=523s
transcript:
>> I should also note that there are even steel alloys whose rust is protective! Weathering steel (sometimes known by its trade name of Corten Steel) is a group of alloys that are naturally resilient against rust because of passivation. A special blend of elements, including manganese, nickel, silicon, and chromium don’t keep the steel from rusting, but they allow the layer of rust to stay attached, forming a protective layer that significantly slows corrosion.
My hope is that Rust may provide a layer of Corten Steel to the Linux
kernel to help us protect newly written driver code from memory safety
related issues, so that Linux remains the best option for developing
products for the next 30 years. I also suspect it may bring in a whole
new generation of hackers to the kernel ecosystem. That is my
blessing for Rust in the Linux kernel.
--
Thanks,
~Nick Desaulniers
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH v9 23/27] Kbuild: add Rust support
2022-08-05 15:42 ` [PATCH v9 23/27] Kbuild: add " Miguel Ojeda
2022-08-17 20:26 ` Kees Cook
2022-08-22 22:35 ` Nick Desaulniers
@ 2022-09-12 16:07 ` Masahiro Yamada
2022-09-12 16:18 ` Miguel Ojeda
2 siblings, 1 reply; 9+ messages in thread
From: Masahiro Yamada @ 2022-09-12 16:07 UTC (permalink / raw)
To: Miguel Ojeda
Cc: Linus Torvalds, Greg Kroah-Hartman, rust-for-linux,
Linux Kernel Mailing List, Linux FS-devel Mailing List, patches,
Jarkko Sakkinen, Alex Gaynor, Finn Behrens, Adam Bratschi-Kaye,
Wedson Almeida Filho, Michael Ellerman, Sven Van Asbroeck,
Gary Guo, Boris-Chengbiao Zhou, Boqun Feng, Douglas Su,
Dariusz Sosnowski, Antonio Terceiro, Daniel Xu,
Björn Roy Baron, Martin Rodriguez Reboredo, Michal Marek,
Nick Desaulniers, Linux Kbuild mailing list
On Sat, Aug 6, 2022 at 12:44 AM Miguel Ojeda <ojeda@kernel.org> wrote:
>
> Having most of the new files in place, we now enable Rust support
> in the build system, including `Kconfig` entries related to Rust,
> the Rust configuration printer and a few other bits.
>
> Co-developed-by: Alex Gaynor <alex.gaynor@gmail.com>
> Signed-off-by: Alex Gaynor <alex.gaynor@gmail.com>
> Co-developed-by: Finn Behrens <me@kloenk.de>
> Signed-off-by: Finn Behrens <me@kloenk.de>
> Co-developed-by: Adam Bratschi-Kaye <ark.email@gmail.com>
> Signed-off-by: Adam Bratschi-Kaye <ark.email@gmail.com>
> Co-developed-by: Wedson Almeida Filho <wedsonaf@google.com>
> Signed-off-by: Wedson Almeida Filho <wedsonaf@google.com>
> Co-developed-by: Michael Ellerman <mpe@ellerman.id.au>
> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
> Co-developed-by: Sven Van Asbroeck <thesven73@gmail.com>
> Signed-off-by: Sven Van Asbroeck <thesven73@gmail.com>
> Co-developed-by: Gary Guo <gary@garyguo.net>
> Signed-off-by: Gary Guo <gary@garyguo.net>
> Co-developed-by: Boris-Chengbiao Zhou <bobo1239@web.de>
> Signed-off-by: Boris-Chengbiao Zhou <bobo1239@web.de>
> Co-developed-by: Boqun Feng <boqun.feng@gmail.com>
> Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
> Co-developed-by: Douglas Su <d0u9.su@outlook.com>
> Signed-off-by: Douglas Su <d0u9.su@outlook.com>
> Co-developed-by: Dariusz Sosnowski <dsosnowski@dsosnowski.pl>
> Signed-off-by: Dariusz Sosnowski <dsosnowski@dsosnowski.pl>
> Co-developed-by: Antonio Terceiro <antonio.terceiro@linaro.org>
> Signed-off-by: Antonio Terceiro <antonio.terceiro@linaro.org>
> Co-developed-by: Daniel Xu <dxu@dxuuu.xyz>
> Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
> Co-developed-by: Björn Roy Baron <bjorn3_gh@protonmail.com>
> Signed-off-by: Björn Roy Baron <bjorn3_gh@protonmail.com>
> Co-developed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
> Signed-off-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
> Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
> ---
> .gitignore | 2 +
> Makefile | 172 ++++++++++++++-
> arch/Kconfig | 6 +
> include/linux/compiler_types.h | 6 +-
> init/Kconfig | 46 +++-
> kernel/configs/rust.config | 1 +
> lib/Kconfig.debug | 34 +++
> rust/.gitignore | 8 +
> rust/Makefile | 381 +++++++++++++++++++++++++++++++++
> rust/bindgen_parameters | 21 ++
> scripts/Kconfig.include | 6 +-
> scripts/Makefile | 3 +
> scripts/Makefile.build | 60 ++++++
> scripts/Makefile.debug | 10 +
> scripts/Makefile.host | 34 ++-
> scripts/Makefile.lib | 12 ++
> scripts/Makefile.modfinal | 8 +-
> scripts/cc-version.sh | 12 +-
> scripts/kconfig/confdata.c | 75 +++++++
> scripts/min-tool-version.sh | 6 +
> 20 files changed, 877 insertions(+), 26 deletions(-)
> create mode 100644 kernel/configs/rust.config
> create mode 100644 rust/.gitignore
> create mode 100644 rust/Makefile
> create mode 100644 rust/bindgen_parameters
>
> diff --git a/.gitignore b/.gitignore
> index 97e085d613a2..5da004814678 100644
> --- a/.gitignore
> +++ b/.gitignore
> @@ -37,6 +37,8 @@
> *.o
> *.o.*
> *.patch
> +*.rmeta
> +*.rsi
> *.s
> *.so
> *.so.dbg
> diff --git a/Makefile b/Makefile
> index df92892325ae..a105cb893b4c 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -120,6 +120,15 @@ endif
>
> export KBUILD_CHECKSRC
>
> +# Enable "clippy" (a linter) as part of the Rust compilation.
> +#
> +# Use 'make CLIPPY=1' to enable it.
> +ifeq ("$(origin CLIPPY)", "command line")
> + KBUILD_CLIPPY := $(CLIPPY)
> +endif
> +
> +export KBUILD_CLIPPY
> +
> # Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
> # directory of external module to build. Setting M= takes precedence.
> ifeq ("$(origin M)", "command line")
> @@ -267,14 +276,14 @@ no-dot-config-targets := $(clean-targets) \
> cscope gtags TAGS tags help% %docs check% coccicheck \
> $(version_h) headers headers_% archheaders archscripts \
> %asm-generic kernelversion %src-pkg dt_binding_check \
> - outputmakefile
> + outputmakefile rustavailable rustfmt rustfmtcheck
> # Installation targets should not require compiler. Unfortunately, vdso_install
> # is an exception where build artifacts may be updated. This must be fixed.
> no-compiler-targets := $(no-dot-config-targets) install dtbs_install \
> headers_install modules_install kernelrelease image_name
> no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease \
> image_name
> -single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
> +single-targets := %.a %.i %.rsi %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
>
> config-build :=
> mixed-build :=
> @@ -436,6 +445,7 @@ else
> HOSTCC = gcc
> HOSTCXX = g++
> endif
> +HOSTRUSTC = rustc
> HOSTPKG_CONFIG = pkg-config
>
> KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
> @@ -444,8 +454,26 @@ KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
> KBUILD_USERCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(USERCFLAGS)
> KBUILD_USERLDFLAGS := $(USERLDFLAGS)
>
> +# These flags apply to all Rust code in the tree, including the kernel and
> +# host programs.
> +export rust_common_flags := --edition=2021 \
> + -Zbinary_dep_depinfo=y \
Let me ask a question about the host_rust rule.
If I directly run the build command from the command line,
I get an error, like follows:
$ rustc --edition=2021 -Zbinary_dep_depinfo=y -Dunsafe_op_in_unsafe_fn
-Drust_2018_idioms -Dunreachable_pub -Dnon_ascii_idents -Wmissing_docs
-Drustdoc::missing_crate_level_docs -Dclippy::correctness
-Dclippy::style -Dclippy::suspicious -Dclippy::complexity
-Dclippy::perf -Dclippy::let_unit_value -Dclippy::mut_mut
-Dclippy::needless_bitwise_bool -Dclippy::needless_continue
-Wclippy::dbg_macro -O -Cstrip=debuginfo -Zallow-features=
--emit=dep-info,link --out-dir=scripts/
../scripts/generate_rust_target.rs
error: the option `Z` is only accepted on the nightly compiler
This is the same command recorded as in
scripts/.generate_rust_target.cmd
Why no error when it is invoked from Makefile?
I have not figured out where this difference comes from.
--
Best Regards
Masahiro Yamada
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH v9 23/27] Kbuild: add Rust support
2022-09-12 16:07 ` Masahiro Yamada
@ 2022-09-12 16:18 ` Miguel Ojeda
2022-09-13 6:37 ` Masahiro Yamada
0 siblings, 1 reply; 9+ messages in thread
From: Miguel Ojeda @ 2022-09-12 16:18 UTC (permalink / raw)
To: Masahiro Yamada
Cc: Miguel Ojeda, Linus Torvalds, Greg Kroah-Hartman, rust-for-linux,
Linux Kernel Mailing List, Linux FS-devel Mailing List, patches,
Jarkko Sakkinen, Alex Gaynor, Finn Behrens, Adam Bratschi-Kaye,
Wedson Almeida Filho, Michael Ellerman, Sven Van Asbroeck,
Gary Guo, Boris-Chengbiao Zhou, Boqun Feng, Douglas Su,
Dariusz Sosnowski, Antonio Terceiro, Daniel Xu,
Björn Roy Baron, Martin Rodriguez Reboredo, Michal Marek,
Nick Desaulniers, Linux Kbuild mailing list
Hi Masahiro,
On Mon, Sep 12, 2022 at 5:08 PM Masahiro Yamada <masahiroy@kernel.org> wrote:
>
> I have not figured out where this difference comes from.
It is the `RUSTC_BOOTSTRAP` environment variable: it allows to use
unstable featuers in the stable compiler.
We currently set it in the global `Makefile`, but we could be more
explicit and do it on each command if you think that would be better.
If you want that we keep using the global export, then we can add a
comment explaining this to clarify.
Cheers,
Miguel
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH v9 23/27] Kbuild: add Rust support
2022-09-12 16:18 ` Miguel Ojeda
@ 2022-09-13 6:37 ` Masahiro Yamada
0 siblings, 0 replies; 9+ messages in thread
From: Masahiro Yamada @ 2022-09-13 6:37 UTC (permalink / raw)
To: Miguel Ojeda
Cc: Miguel Ojeda, Linus Torvalds, Greg Kroah-Hartman, rust-for-linux,
Linux Kernel Mailing List, Linux FS-devel Mailing List, patches,
Jarkko Sakkinen, Alex Gaynor, Finn Behrens, Adam Bratschi-Kaye,
Wedson Almeida Filho, Michael Ellerman, Sven Van Asbroeck,
Gary Guo, Boris-Chengbiao Zhou, Boqun Feng, Douglas Su,
Dariusz Sosnowski, Antonio Terceiro, Daniel Xu,
Björn Roy Baron, Martin Rodriguez Reboredo, Michal Marek,
Nick Desaulniers, Linux Kbuild mailing list
On Tue, Sep 13, 2022 at 1:18 AM Miguel Ojeda
<miguel.ojeda.sandonis@gmail.com> wrote:
>
> Hi Masahiro,
>
> On Mon, Sep 12, 2022 at 5:08 PM Masahiro Yamada <masahiroy@kernel.org> wrote:
> >
> > I have not figured out where this difference comes from.
>
> It is the `RUSTC_BOOTSTRAP` environment variable: it allows to use
> unstable featuers in the stable compiler.
Thanks, I learned a new thing.
>
> We currently set it in the global `Makefile`, but we could be more
> explicit and do it on each command if you think that would be better.
I checked "make compile_commands.json", but it collects build commands
only for C.
I did not see any bad scenario with the current approach.
>
> If you want that we keep using the global export, then we can add a
> comment explaining this to clarify.
>
> Cheers,
> Miguel
--
Best Regards
Masahiro Yamada
^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2022-09-13 6:38 UTC | newest]
Thread overview: 9+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2022-08-05 15:41 [PATCH v9 00/27] Rust support Miguel Ojeda
2022-08-05 15:42 ` [PATCH v9 23/27] Kbuild: add " Miguel Ojeda
2022-08-17 20:26 ` Kees Cook
2022-08-17 20:56 ` Miguel Ojeda
2022-08-22 22:35 ` Nick Desaulniers
2022-09-12 16:07 ` Masahiro Yamada
2022-09-12 16:18 ` Miguel Ojeda
2022-09-13 6:37 ` Masahiro Yamada
2022-08-05 15:42 ` [PATCH v9 24/27] docs: add Rust documentation Miguel Ojeda
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