[PATCH v7 00/25] Rust support

[Miguel Ojeda]

Rust support

This is the patch series (v7) 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-fo...@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...@kernel.org/
v1: https://lore.kernel.org/lkml/20210704202756...@kernel.org/
v2: https://lore.kernel.org/lkml/2021120614031...@kernel.org/
v3: https://lore.kernel.org/lkml/2022011705334...@kernel.org/
v4: https://lore.kernel.org/lkml/2022021213041...@kernel.org/
v5: https://lore.kernel.org/lkml/20220317181032...@kernel.org/
v6: https://lore.kernel.org/lkml/20220507052451...@kernel.org/

This is a small round to address the comments made in v6 plus a few
related changes:

- Added `%pA` to `Documentation/core-api/printk-formats.rst`.

- Added `checkpatch.pl` patch to search for `%pA` in C code.

- Added `checkpatch.pl` patch to enable language-independent checks.

- Added UML (x86_64) support, for KUnit (thanks David Gow!).

- Added inline licensing information ("Apache-2.0 OR MIT") in
the commit message of the `alloc` patch, as well as in
`rust/alloc/README.md` in the following patch.

- Added SPDX license identifiers to `Documentation/rust/`.

- Reformatted `Documentation/rust/arch-support.rst` list table
into simple table.

- Removed logo from documentation patch; used Linux GIF one for
the Rust generated docs in its place (to be replaced with
the SVG one once available).

- Used `"GPL"` instead of `"GPL v2"` for the `license` field of the
`module!` macro.

- Moved `module_misc_device!` macro in `samples/rust/rust_random.rs`
to the top of the file in `samples/rust/` for consistency.

- Sorted `#include` lists in `rust/kernel/bindings_helper.h`
and `rust/helpers.c`.

- Fixed some English typos.

- Made the patches more `checkpatch.pl`-clean overall.

- Picked up Reviewed-by and Acked-by tags.


## 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 has just arrived in `linux-next`, as usual.
Similarly, the preview docs for this series can be seen at:

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:

https://github.com/Rust-for-Linux/linux/issues/2


## Conferences, meetings and liaisons

We would like to remind everyone about the Rust MC (microconference)
of LPC 2022 (Linux Plumbers Conference):

https://lpc.events/event/16/contributions/1159/

The Rust MC intends to cover talks and discussions on both Rust for
Linux as well as other non-kernel Rust topics. The Call for Proposals
is open!


## 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:

- Kees Cook for his reviews of some of the v6 patches.

- David Gow and Brendan Higgins for their reviews of the KUnit
prerequisite patch and their feedback.

- Jonathan Corbet and Akira Yokosawa for their review of the
documentation patch and feedback on documentation rules.

- Gary Guo for working on improvements to the Rust compiler that
could make our `static_assert!` macro applicable in more cases.

- bjorn3 for working on making `rustc_parse_format` compile on
a stable Rust compiler so that it may be used by lightweight
formatting systems (for instance, by the kernel).

- As usual, bjorn3 and Gary Guo for all the input on Rust compiler
details, reviews and suggestions.

- Esteban Blanc, Arthur Cohen and Martin Schmidt for rebasing their
SPI abstraction work.

- Maciej Falkowski for continuing his work on the Samsung Exynos
TRNG driver and the required abstractions around it, such as
adding `delay`, `ktime` and `iopoll` abstractions, new methods
to `platform::Device` and run-time power management abstractions.

- Yuheng Su for working on cleaning up the `Module::init` interface.

- Peng Hao for working on wrapping `mm_struct`.

- Sergio González Collado for continuing his work on the GitHub CI
problem matchers.

- 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`.

- 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 (1):
kallsyms: avoid hardcoding the buffer size

Gary Guo (2):
rust: add `build_error` crate
vsprintf: add new `%pA` format specifier

Miguel Ojeda (18):
kallsyms: support "big" kernel symbols
kallsyms: increase maximum kernel symbol length to 512
kunit: take `kunit_assert` as `const`
rust: add C helpers
rust: add `compiler_builtins` crate
rust: import upstream `alloc` crate
rust: adapt `alloc` crate to the kernel
rust: add `macros` crate
rust: export generated symbols
scripts: checkpatch: diagnose uses of `%pA` in the C side
scripts: checkpatch: enable language-independent checks for Rust
scripts: add `rustdoc_test_{builder,gen}.py` scripts
scripts: add `generate_rust_analyzer.py` scripts
scripts: decode_stacktrace: demangle Rust symbols
docs: add Rust documentation
Kbuild: add Rust support
samples: add Rust examples
MAINTAINERS: Rust

Wedson Almeida Filho (4):
rust: add `kernel` crate's `sync` module
rust: add `kernel` crate
[RFC] drivers: gpio: PrimeCell PL061 in Rust
[RFC] drivers: android: Binder IPC in Rust

.gitignore | 5 +
.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 | 25 +
Documentation/rust/coding-guidelines.rst | 216 ++
Documentation/rust/general-information.rst | 79 +
Documentation/rust/index.rst | 22 +
Documentation/rust/quick-start.rst | 232 ++
MAINTAINERS | 15 +
Makefile | 175 +-
arch/Kconfig | 6 +
arch/arm/Kconfig | 1 +
arch/arm64/Kconfig | 1 +
arch/powerpc/Kconfig | 1 +
arch/riscv/Kconfig | 1 +
arch/riscv/Makefile | 5 +
arch/um/Kconfig | 1 +
arch/x86/Kconfig | 1 +
arch/x86/Makefile | 14 +
drivers/android/Kconfig | 6 +
drivers/android/Makefile | 2 +
drivers/android/allocation.rs | 266 ++
drivers/android/context.rs | 80 +
drivers/android/defs.rs | 99 +
drivers/android/node.rs | 476 +++
drivers/android/process.rs | 960 +++++
drivers/android/range_alloc.rs | 189 +
drivers/android/rust_binder.rs | 111 +
drivers/android/thread.rs | 870 +++++
drivers/android/transaction.rs | 326 ++
drivers/gpio/Kconfig | 8 +
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio_pl061_rust.rs | 370 ++
include/kunit/test.h | 2 +-
include/linux/kallsyms.h | 2 +-
include/linux/spinlock.h | 25 +-
include/uapi/linux/android/binder.h | 28 +-
init/Kconfig | 45 +-
kernel/kallsyms.c | 26 +-
kernel/livepatch/core.c | 4 +-
lib/Kconfig.debug | 155 +
lib/kunit/test.c | 4 +-
lib/vsprintf.c | 13 +
rust/.gitignore | 10 +
rust/Makefile | 398 +++
rust/alloc/README.md | 33 +
rust/alloc/alloc.rs | 438 +++
rust/alloc/borrow.rs | 498 +++
rust/alloc/boxed.rs | 2007 +++++++++++
rust/alloc/collections/mod.rs | 156 +
rust/alloc/fmt.rs | 601 ++++
rust/alloc/lib.rs | 226 ++
rust/alloc/macros.rs | 127 +
rust/alloc/raw_vec.rs | 567 +++
rust/alloc/slice.rs | 1282 +++++++
rust/alloc/str.rs | 632 ++++
rust/alloc/string.rs | 2869 +++++++++++++++
rust/alloc/vec/drain.rs | 186 +
rust/alloc/vec/drain_filter.rs | 145 +
rust/alloc/vec/into_iter.rs | 356 ++
rust/alloc/vec/is_zero.rs | 106 +
rust/alloc/vec/mod.rs | 3362 ++++++++++++++++++
rust/alloc/vec/partial_eq.rs | 49 +
rust/alloc/vec/set_len_on_drop.rs | 30 +
rust/alloc/vec/spec_extend.rs | 174 +
rust/bindgen_parameters | 17 +
rust/build_error.rs | 29 +
rust/compiler_builtins.rs | 57 +
rust/exports.c | 20 +
rust/helpers.c | 644 ++++
rust/kernel/allocator.rs | 65 +
rust/kernel/amba.rs | 257 ++
rust/kernel/bindings.rs | 47 +
rust/kernel/bindings_helper.h | 46 +
rust/kernel/build_assert.rs | 82 +
rust/kernel/c_types.rs | 119 +
rust/kernel/chrdev.rs | 207 ++
rust/kernel/clk.rs | 79 +
rust/kernel/cred.rs | 46 +
rust/kernel/device.rs | 546 +++
rust/kernel/driver.rs | 442 +++
rust/kernel/error.rs | 565 +++
rust/kernel/file.rs | 860 +++++
rust/kernel/gpio.rs | 478 +++
rust/kernel/hwrng.rs | 242 ++
rust/kernel/io_buffer.rs | 153 +
rust/kernel/io_mem.rs | 275 ++
rust/kernel/iov_iter.rs | 81 +
rust/kernel/irq.rs | 411 +++
rust/kernel/kasync.rs | 6 +
rust/kernel/kasync/net.rs | 322 ++
rust/kernel/kunit.rs | 91 +
rust/kernel/lib.rs | 261 ++
rust/kernel/linked_list.rs | 247 ++
rust/kernel/miscdev.rs | 291 ++
rust/kernel/mm.rs | 149 +
rust/kernel/module_param.rs | 498 +++
rust/kernel/net.rs | 392 ++
rust/kernel/net/filter.rs | 447 +++
rust/kernel/of.rs | 63 +
rust/kernel/pages.rs | 144 +
rust/kernel/platform.rs | 223 ++
rust/kernel/power.rs | 118 +
rust/kernel/prelude.rs | 36 +
rust/kernel/print.rs | 405 +++
rust/kernel/random.rs | 42 +
rust/kernel/raw_list.rs | 361 ++
rust/kernel/rbtree.rs | 563 +++
rust/kernel/revocable.rs | 161 +
rust/kernel/security.rs | 38 +
rust/kernel/static_assert.rs | 38 +
rust/kernel/std_vendor.rs | 160 +
rust/kernel/str.rs | 597 ++++
rust/kernel/sync.rs | 161 +
rust/kernel/sync/arc.rs | 503 +++
rust/kernel/sync/condvar.rs | 138 +
rust/kernel/sync/guard.rs | 169 +
rust/kernel/sync/locked_by.rs | 111 +
rust/kernel/sync/mutex.rs | 153 +
rust/kernel/sync/nowait.rs | 188 +
rust/kernel/sync/revocable.rs | 250 ++
rust/kernel/sync/rwsem.rs | 197 +
rust/kernel/sync/seqlock.rs | 202 ++
rust/kernel/sync/smutex.rs | 295 ++
rust/kernel/sync/spinlock.rs | 360 ++
rust/kernel/sysctl.rs | 199 ++
rust/kernel/task.rs | 175 +
rust/kernel/types.rs | 679 ++++
rust/kernel/user_ptr.rs | 175 +
rust/macros/helpers.rs | 79 +
rust/macros/lib.rs | 94 +
rust/macros/module.rs | 631 ++++
samples/Kconfig | 2 +
samples/Makefile | 1 +
samples/rust/Kconfig | 140 +
samples/rust/Makefile | 16 +
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_chrdev.rs | 50 +
samples/rust/rust_minimal.rs | 35 +
samples/rust/rust_miscdev.rs | 143 +
samples/rust/rust_module_parameters.rs | 69 +
samples/rust/rust_netfilter.rs | 54 +
samples/rust/rust_platform.rs | 22 +
samples/rust/rust_print.rs | 54 +
samples/rust/rust_random.rs | 60 +
samples/rust/rust_semaphore.rs | 171 +
samples/rust/rust_semaphore_c.c | 212 ++
samples/rust/rust_stack_probing.rs | 36 +
samples/rust/rust_sync.rs | 93 +
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 | 8 +-
scripts/decode_stacktrace.sh | 14 +
scripts/generate_rust_analyzer.py | 134 +
scripts/generate_rust_target.rs | 227 ++
scripts/is_rust_module.sh | 13 +
scripts/kallsyms.c | 47 +-
scripts/kconfig/confdata.c | 75 +
scripts/min-tool-version.sh | 6 +
scripts/rust-is-available-bindgen-libclang.h | 2 +
scripts/rust-is-available.sh | 158 +
scripts/rustdoc_test_builder.py | 59 +
scripts/rustdoc_test_gen.py | 164 +
tools/include/linux/kallsyms.h | 2 +-
tools/lib/perf/include/perf/event.h | 2 +-
tools/lib/symbol/kallsyms.h | 2 +-
182 files changed, 37614 insertions(+), 69 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 drivers/android/allocation.rs
create mode 100644 drivers/android/context.rs
create mode 100644 drivers/android/defs.rs
create mode 100644 drivers/android/node.rs
create mode 100644 drivers/android/process.rs
create mode 100644 drivers/android/range_alloc.rs
create mode 100644 drivers/android/rust_binder.rs
create mode 100644 drivers/android/thread.rs
create mode 100644 drivers/android/transaction.rs
create mode 100644 drivers/gpio/gpio_pl061_rust.rs
create mode 100644 rust/.gitignore
create mode 100644 rust/Makefile
create mode 100644 rust/alloc/README.md
create mode 100644 rust/alloc/alloc.rs
create mode 100644 rust/alloc/borrow.rs
create mode 100644 rust/alloc/boxed.rs
create mode 100644 rust/alloc/collections/mod.rs
create mode 100644 rust/alloc/fmt.rs
create mode 100644 rust/alloc/lib.rs
create mode 100644 rust/alloc/macros.rs
create mode 100644 rust/alloc/raw_vec.rs
create mode 100644 rust/alloc/slice.rs
create mode 100644 rust/alloc/str.rs
create mode 100644 rust/alloc/string.rs
create mode 100644 rust/alloc/vec/drain.rs
create mode 100644 rust/alloc/vec/drain_filter.rs
create mode 100644 rust/alloc/vec/into_iter.rs
create mode 100644 rust/alloc/vec/is_zero.rs
create mode 100644 rust/alloc/vec/mod.rs
create mode 100644 rust/alloc/vec/partial_eq.rs
create mode 100644 rust/alloc/vec/set_len_on_drop.rs
create mode 100644 rust/alloc/vec/spec_extend.rs
create mode 100644 rust/bindgen_parameters
create mode 100644 rust/build_error.rs
create mode 100644 rust/compiler_builtins.rs
create mode 100644 rust/exports.c
create mode 100644 rust/helpers.c
create mode 100644 rust/kernel/allocator.rs
create mode 100644 rust/kernel/amba.rs
create mode 100644 rust/kernel/bindings.rs
create mode 100644 rust/kernel/bindings_helper.h
create mode 100644 rust/kernel/build_assert.rs
create mode 100644 rust/kernel/c_types.rs
create mode 100644 rust/kernel/chrdev.rs
create mode 100644 rust/kernel/clk.rs
create mode 100644 rust/kernel/cred.rs
create mode 100644 rust/kernel/device.rs
create mode 100644 rust/kernel/driver.rs
create mode 100644 rust/kernel/error.rs
create mode 100644 rust/kernel/file.rs
create mode 100644 rust/kernel/gpio.rs
create mode 100644 rust/kernel/hwrng.rs
create mode 100644 rust/kernel/io_buffer.rs
create mode 100644 rust/kernel/io_mem.rs
create mode 100644 rust/kernel/iov_iter.rs
create mode 100644 rust/kernel/irq.rs
create mode 100644 rust/kernel/kasync.rs
create mode 100644 rust/kernel/kasync/net.rs
create mode 100644 rust/kernel/kunit.rs
create mode 100644 rust/kernel/lib.rs
create mode 100644 rust/kernel/linked_list.rs
create mode 100644 rust/kernel/miscdev.rs
create mode 100644 rust/kernel/mm.rs
create mode 100644 rust/kernel/module_param.rs
create mode 100644 rust/kernel/net.rs
create mode 100644 rust/kernel/net/filter.rs
create mode 100644 rust/kernel/of.rs
create mode 100644 rust/kernel/pages.rs
create mode 100644 rust/kernel/platform.rs
create mode 100644 rust/kernel/power.rs
create mode 100644 rust/kernel/prelude.rs
create mode 100644 rust/kernel/print.rs
create mode 100644 rust/kernel/random.rs
create mode 100644 rust/kernel/raw_list.rs
create mode 100644 rust/kernel/rbtree.rs
create mode 100644 rust/kernel/revocable.rs
create mode 100644 rust/kernel/security.rs
create mode 100644 rust/kernel/static_assert.rs
create mode 100644 rust/kernel/std_vendor.rs
create mode 100644 rust/kernel/str.rs
create mode 100644 rust/kernel/sync.rs
create mode 100644 rust/kernel/sync/arc.rs
create mode 100644 rust/kernel/sync/condvar.rs
create mode 100644 rust/kernel/sync/guard.rs
create mode 100644 rust/kernel/sync/locked_by.rs
create mode 100644 rust/kernel/sync/mutex.rs
create mode 100644 rust/kernel/sync/nowait.rs
create mode 100644 rust/kernel/sync/revocable.rs
create mode 100644 rust/kernel/sync/rwsem.rs
create mode 100644 rust/kernel/sync/seqlock.rs
create mode 100644 rust/kernel/sync/smutex.rs
create mode 100644 rust/kernel/sync/spinlock.rs
create mode 100644 rust/kernel/sysctl.rs
create mode 100644 rust/kernel/task.rs
create mode 100644 rust/kernel/types.rs
create mode 100644 rust/kernel/user_ptr.rs
create mode 100644 rust/macros/helpers.rs
create mode 100644 rust/macros/lib.rs
create mode 100644 rust/macros/module.rs
create mode 100644 samples/rust/Kconfig
create mode 100644 samples/rust/Makefile
create mode 100644 samples/rust/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_chrdev.rs
create mode 100644 samples/rust/rust_minimal.rs
create mode 100644 samples/rust/rust_miscdev.rs
create mode 100644 samples/rust/rust_module_parameters.rs
create mode 100644 samples/rust/rust_netfilter.rs
create mode 100644 samples/rust/rust_platform.rs
create mode 100644 samples/rust/rust_print.rs
create mode 100644 samples/rust/rust_random.rs
create mode 100644 samples/rust/rust_semaphore.rs
create mode 100644 samples/rust/rust_semaphore_c.c
create mode 100644 samples/rust/rust_stack_probing.rs
create mode 100644 samples/rust/rust_sync.rs
create mode 100755 scripts/generate_rust_analyzer.py
create mode 100644 scripts/generate_rust_target.rs
create mode 100755 scripts/is_rust_module.sh
create mode 100644 scripts/rust-is-available-bindgen-libclang.h
create mode 100755 scripts/rust-is-available.sh
create mode 100755 scripts/rustdoc_test_builder.py
create mode 100755 scripts/rustdoc_test_gen.py


base-commit: 4b0986a3613c92f4ec1bdc7f60ec66fea135991f
--
2.36.1

[Miguel Ojeda]

The `kunit_do_failed_assertion` function passes its
`struct kunit_assert` argument to `kunit_fail`. This one,
in turn, calls its `format` field passing the assert again
as a `const` pointer.

Therefore, the whole chain may be made `const`.

Reviewed-by: Daniel Latypov <dlat...@google.com>
Reviewed-by: Brendan Higgins <brendan...@google.com>
Signed-off-by: Miguel Ojeda <oj...@kernel.org>
---
This is a prerequisite patch, independently submitted at:

https://lore.kernel.org/lkml/20220502093...@kernel.org/

include/kunit/test.h | 2 +-
lib/kunit/test.c | 4 ++--
2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/include/kunit/test.h b/include/kunit/test.h
index 00b9ff7783ab..2eff4f1beb42 100644
--- a/include/kunit/test.h
+++ b/include/kunit/test.h
@@ -774,7 +774,7 @@ void __printf(2, 3) kunit_log_append(char *log, const char *fmt, ...);
void kunit_do_failed_assertion(struct kunit *test,
const struct kunit_loc *loc,
enum kunit_assert_type type,
- struct kunit_assert *assert,
+ const struct kunit_assert *assert,
const char *fmt, ...);

#define KUNIT_ASSERTION(test, assert_type, pass, assert_class, INITIALIZER, fmt, ...) do { \
diff --git a/lib/kunit/test.c b/lib/kunit/test.c
index 3bca3bf5c15b..b84aed09a009 100644
--- a/lib/kunit/test.c
+++ b/lib/kunit/test.c
@@ -241,7 +241,7 @@ static void kunit_print_string_stream(struct kunit *test,
}

static void kunit_fail(struct kunit *test, const struct kunit_loc *loc,
- enum kunit_assert_type type, struct kunit_assert *assert,
+ enum kunit_assert_type type, const struct kunit_assert *assert,
const struct va_format *message)
{
struct string_stream *stream;
@@ -281,7 +281,7 @@ static void __noreturn kunit_abort(struct kunit *test)
void kunit_do_failed_assertion(struct kunit *test,
const struct kunit_loc *loc,
enum kunit_assert_type type,
- struct kunit_assert *assert,
+ const struct kunit_assert *assert,
const char *fmt, ...)
{
va_list args;
--
2.36.1

[Daniel Latypov]

On Sun, May 22, 2022 at 7:03 PM Miguel Ojeda <oj...@kernel.org> wrote:
>
> The `kunit_do_failed_assertion` function passes its
> `struct kunit_assert` argument to `kunit_fail`. This one,
> in turn, calls its `format` field passing the assert again
> as a `const` pointer.
>
> Therefore, the whole chain may be made `const`.
>
> Reviewed-by: Daniel Latypov <dlat...@google.com>
> Reviewed-by: Brendan Higgins <brendan...@google.com>
> Signed-off-by: Miguel Ojeda <oj...@kernel.org>
> ---
> This is a prerequisite patch, independently submitted at:
>
> https://lore.kernel.org/lkml/20220502093...@kernel.org/

FYI, we'd asked Shuah to pick this patch up in her "kunit" branch.
It's applied here:
https://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest.git/commit/?h=kunit&id=7466886b400b1904ce30fa311904849e314a2cf4

It had previously seemed unclear if this series could make it for the
5.19 merge window (but it now looks like there's interest in trying it
out early on).

Daniel

[Shuah Khan]

I am just about send pull request with this patch included.

thanks,
-- Shuah

[Miguel Ojeda]

> I am just about send pull request with this patch included.

Thank you, Daniel and Shuah!

Cheers,
Miguel

[Conor Dooley]

Hey,

Maybe I am just missing something blatantly obvious here, but trying
to build rust support in -next fails for me. I am using ClangBuiltLinux
clang version 15.0.0 5b0788fef86ed7008a11f6ee19b9d86d42b6fcfa and LLD
15.0.0. Is it just expected that building -next with rust support is
not a good idea?
My defconfig is the default RISC-V one plus:
CONFIG_RUST=y
CONFIG_SAMPLES=y
CONFIG_SAMPLES_RUST=y
CONFIG_SAMPLE_RUST_MINIMAL=y

Thanks,
Conor.

Fail log:
UPD rust/target.json
BINDGEN rust/bindings_generated.rs
BINDGEN rust/bindings_helpers_generated.rs
RUSTC L rust/core.o
EXPORTS rust/exports_core_generated.h
RUSTC P rust/libmacros.so
RUSTC L rust/compiler_builtins.o
RUSTC L rust/alloc.o
RUSTC L rust/build_error.o
EXPORTS rust/exports_alloc_generated.h
RUSTC L rust/kernel.o
error[E0428]: the name `maple_enode` is defined multiple times
--> linux/rust/bindings_generated.rs:18009:1
|
18006 | pub struct maple_enode {
| ---------------------- previous definition of the type `maple_enode` here
...
18009 | pub type maple_enode = *mut maple_enode;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `maple_enode` redefined here
|
= note: `maple_enode` must be defined only once in the type namespace of this module

error[E0428]: the name `maple_pnode` is defined multiple times
--> linux/rust/bindings_generated.rs:18015:1
|
18012 | pub struct maple_pnode {
| ---------------------- previous definition of the type `maple_pnode` here
...
18015 | pub type maple_pnode = *mut maple_pnode;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `maple_pnode` redefined here
|
= note: `maple_pnode` must be defined only once in the type namespace of this module

error[E0391]: cycle detected when expanding type alias `bindings::bindings_raw::maple_pnode`
--> linux/rust/bindings_generated.rs:18015:29
|
18015 | pub type maple_pnode = *mut maple_pnode;
| ^^^^^^^^^^^
|
= note: ...which immediately requires expanding type alias `bindings::bindings_raw::maple_pnode` again
= note: type aliases cannot be recursive
= help: consider using a struct, enum, or union instead to break the cycle
= help: see <https://doc.rust-lang.org/reference/types.html#recursive-types> for more information
note: cycle used when computing type of `bindings::bindings_raw::maple_range_64::parent`
--> linux/rust/bindings_generated.rs:18058:22
|
18058 | pub parent: *mut maple_pnode,
| ^^^^^^^^^^^

error[E0391]: cycle detected when expanding type alias `bindings::bindings_raw::maple_enode`
--> linux/rust/bindings_generated.rs:18009:29
|
18009 | pub type maple_enode = *mut maple_enode;
| ^^^^^^^^^^^
|
= note: ...which immediately requires expanding type alias `bindings::bindings_raw::maple_enode` again
= note: type aliases cannot be recursive
= help: consider using a struct, enum, or union instead to break the cycle
= help: see <https://doc.rust-lang.org/reference/types.html#recursive-types> for more information
note: cycle used when computing type of `bindings::bindings_raw::maple_topiary::next`
--> linux/rust/bindings_generated.rs:18340:20
|
18340 | pub next: *mut maple_enode,
| ^^^^^^^^^^^

error[E0117]: only traits defined in the current crate can be implemented for arbitrary types
--> linux/rust/bindings_generated.rs:18005:10
|
18005 | #[derive(Copy, Clone)]
| ^^^^
| |
| impl doesn't use only types from inside the current crate
| `*mut [type error]` is not defined in the current crate
|
= note: define and implement a trait or new type instead
= note: this error originates in the derive macro `Copy` (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0117]: only traits defined in the current crate can be implemented for arbitrary types
--> linux/rust/bindings_generated.rs:18011:10
|
18011 | #[derive(Copy, Clone)]
| ^^^^
| |
| impl doesn't use only types from inside the current crate
| `*mut [type error]` is not defined in the current crate
|
= note: define and implement a trait or new type instead
= note: this error originates in the derive macro `Copy` (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0117]: only traits defined in the current crate can be implemented for arbitrary types
--> linux/rust/bindings_generated.rs:18005:16
|
18005 | #[derive(Copy, Clone)]
| ^^^^^
| |
| impl doesn't use only types from inside the current crate
| `*mut [type error]` is not defined in the current crate
|
= note: define and implement a trait or new type instead
= note: this error originates in the derive macro `Clone` (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0117]: only traits defined in the current crate can be implemented for arbitrary types
--> linux/rust/bindings_generated.rs:18011:16
|
18011 | #[derive(Copy, Clone)]
| ^^^^^
| |
| impl doesn't use only types from inside the current crate
| `*mut [type error]` is not defined in the current crate
|
= note: define and implement a trait or new type instead
= note: this error originates in the derive macro `Clone` (in Nightly builds, run with -Z macro-backtrace for more info)

error: aborting due to 8 previous errors

[Miguel Ojeda]

Hi Conor,

On Sat, Jul 16, 2022 at 2:42 PM Conor Dooley <co...@kernel.org> wrote:
>
> Maybe I am just missing something blatantly obvious here, but trying
> to build rust support in -next fails for me. I am using ClangBuiltLinux
> clang version 15.0.0 5b0788fef86ed7008a11f6ee19b9d86d42b6fcfa and LLD
> 15.0.0. Is it just expected that building -next with rust support is
> not a good idea?

Please see https://github.com/Rust-for-Linux/linux/issues/795 for
details about the maple tree issue.

I will update the `rust-next` branch next week with the new version of
the patches; but if you are interested in developing, please use the
development `rust` branch instead in GitHub for the moment.

Cheers,
Miguel

[Conor....@microchip.com]

On 16/07/2022 14:36, Miguel Ojeda wrote:
> Hi Conor,
>
> On Sat, Jul 16, 2022 at 2:42 PM Conor Dooley <co...@kernel.org> wrote:
>>
>> Maybe I am just missing something blatantly obvious here, but trying
>> to build rust support in -next fails for me. I am using ClangBuiltLinux
>> clang version 15.0.0 5b0788fef86ed7008a11f6ee19b9d86d42b6fcfa and LLD
>> 15.0.0. Is it just expected that building -next with rust support is
>> not a good idea?
>
> Please see https://github.com/Rust-for-Linux/linux/issues/795 for
> details about the maple tree issue.

Ah right, sorry for the noise so. I checked the ml but didn't see a
report there.

>
> I will update the `rust-next` branch next week with the new version of
> the patches; but if you are interested in developing, please use the
> development `rust` branch instead in GitHub for the moment.

Thanks Miguel, good to know! I'll just wait around for a new version.
Just been trying to get my CI etc in order for when rust support lands,
but it sounds like I should be okay as it's a known problem & not some
only-broken-on-riscv thing.

Thanks,
Conor.

[Miguel Ojeda]

On Sat, Jul 16, 2022 at 3:51 PM <Conor....@microchip.com> wrote:
>
> Ah right, sorry for the noise so. I checked the ml but didn't see a
> report there.

No apologies needed -- thanks to you for the report, instead! :)

> Thanks Miguel, good to know! I'll just wait around for a new version.
> Just been trying to get my CI etc in order for when rust support lands,
> but it sounds like I should be okay as it's a known problem & not some
> only-broken-on-riscv thing.

Yeah, it is a simple `bindgen` issue. Thanks a lot for making the
effort to prepare your CI in advance!

Cheers,
Miguel