commit 7498159226772d66f150dd406be462d75964a366 upstream.
Starting with Rust 1.89.0 (expected 2025-08-07), the Rust compiler fails
to build the `rusttest` target due to undefined references such as:
kernel...-cgu.0:(.text....+0x116): undefined reference to
`rust_helper_kunit_get_current_test'
Moreover, tooling like `modpost` gets confused:
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/gpu/drm/nova/nova.o
ERROR: modpost: missing MODULE_LICENSE() in drivers/gpu/nova-core/nova_core.o
The reason behind both issues is that the Rust compiler will now [1]
treat `#[used]` as `#[used(linker)]` instead of `#[used(compiler)]`
for our targets. This means that the retain section flag (`R`,
`SHF_GNU_RETAIN`) will be used and that they will be marked as `unique`
too, with different IDs. In turn, that means we end up with undefined
references that did not get discarded in `rusttest` and that multiple
`.modinfo` sections are generated, which confuse tooling like `modpost`
because they only expect one.
Thus start using `#[used(compiler)]` to keep the previous behavior
and to be explicit about what we want. Sadly, it is an unstable feature
(`used_with_arg`) [2] -- we will talk to upstream Rust about it. The good
news is that it has been available for a long time (Rust >= 1.60) [3].
The changes should also be fine for previous Rust versions, since they
behave the same way as before [4].
Alternatively, we could use `#[no_mangle]` or `#[export_name = ...]`
since those still behave like `#[used(compiler)]`, but of course it is
not really what we want to express, and it requires other changes to
avoid symbol conflicts.
Cc: David Wood <david@davidtw.co>
Cc: Wesley Wiser <wwiser@gmail.com>
Cc: stable@vger.kernel.org # Needed in 6.12.y and later (Rust is pinned in older LTSs).
Link: https://github.com/rust-lang/rust/pull/140872 [1]
Link: https://github.com/rust-lang/rust/issues/93798 [2]
Link: https://github.com/rust-lang/rust/pull/91504 [3]
Link: https://godbolt.org/z/sxzWTMfzW [4]
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Björn Roy Baron <bjorn3_gh@protonmail.com>
Link: https://lore.kernel.org/r/20250712160103.1244945-3-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 249c3a0e53acefc2b06d3b3e1fc28fb2081f878d ]
Place cleanup_module() in .exit.text section. Currently,
cleanup_module() is likely placed in the .text section. It's
inconsistent with the layout of C modules, where cleanup_module() is
placed in .exit.text.
[ Boqun asked for an example of how the section changed to be
put in the log. Tomonori provided the following examples:
C module:
$ objdump -t ~/build/x86/drivers/block/loop.o|grep clean
0000000000000000 l O .exit.data 0000000000000008 __UNIQUE_ID___addressable_cleanup_module412
0000000000000000 g F .exit.text 000000000000009c cleanup_module
Rust module without this patch:
$ objdump -t ~/build/x86/samples/rust/rust_minimal.o|grep clean
00000000000002b0 g F .text 00000000000000c6 cleanup_module
0000000000000000 g O .exit.data 0000000000000008 _R...___UNIQUE_ID___addressable_cleanup_module
Rust module with this patch:
$ objdump -t ~/build/x86/samples/rust/rust_minimal.o|grep clean
0000000000000000 g F .exit.text 00000000000000c6 cleanup_module
0000000000000000 g O .exit.data 0000000000000008 _R...___UNIQUE_ID___addressable_cleanup_module
- Miguel ]
Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Acked-by: Jarkko Sakkinen <jarkko@kernel.org>
Link: https://lore.kernel.org/r/20250308044506.14458-1-fujita.tomonori@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Starting with Rust 1.88.0 (expected 2025-06-26) [1], `rustc` may move
back the `uninlined_format_args` to `style` from `pedantic` (it was
there waiting for rust-analyzer suppotr), and thus we will start to see
lints like:
warning: variables can be used directly in the `format!` string
--> rust/macros/kunit.rs:105:37
|
105 | let kunit_wrapper_fn_name = format!("kunit_rust_wrapper_{}", test);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#uninlined_format_args
help: change this to
|
105 - let kunit_wrapper_fn_name = format!("kunit_rust_wrapper_{}", test);
105 + let kunit_wrapper_fn_name = format!("kunit_rust_wrapper_{test}");
There is even a case that is a pure removal:
warning: variables can be used directly in the `format!` string
--> rust/macros/module.rs:51:13
|
51 | format!("{field}={content}\0", field = field, content = content)
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#uninlined_format_args
help: change this to
|
51 - format!("{field}={content}\0", field = field, content = content)
51 + format!("{field}={content}\0")
The lints all seem like nice cleanups, thus just apply them.
We may want to disable `allow-mixed-uninlined-format-args` in the future.
Cc: stable@vger.kernel.org # Needed in 6.12.y and later (Rust is pinned in older LTSs).
Link: https://github.com/rust-lang/rust-clippy/pull/14160 [1]
Acked-by: Benno Lossin <lossin@kernel.org>
Reviewed-by: Tamir Duberstein <tamird@gmail.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250502140237.1659624-6-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Pull Rust updates from Miguel Ojeda:
"Toolchain and infrastructure:
- Extract the 'pin-init' API from the 'kernel' crate and make it into
a standalone crate.
In order to do this, the contents are rearranged so that they can
easily be kept in sync with the version maintained out-of-tree that
other projects have started to use too (or plan to, like QEMU).
This will reduce the maintenance burden for Benno, who will now
have his own sub-tree, and will simplify future expected changes
like the move to use 'syn' to simplify the implementation.
- Add '#[test]'-like support based on KUnit.
We already had doctests support based on KUnit, which takes the
examples in our Rust documentation and runs them under KUnit.
Now, we are adding the beginning of the support for "normal" tests,
similar to those the '#[test]' tests in userspace Rust. For
instance:
#[kunit_tests(my_suite)]
mod tests {
#[test]
fn my_test() {
assert_eq!(1 + 1, 2);
}
}
Unlike with doctests, the 'assert*!'s do not map to the KUnit
assertion APIs yet.
- Check Rust signatures at compile time for functions called from C
by name.
In particular, introduce a new '#[export]' macro that can be placed
in the Rust function definition. It will ensure that the function
declaration on the C side matches the signature on the Rust
function:
#[export]
pub unsafe extern "C" fn my_function(a: u8, b: i32) -> usize {
// ...
}
The macro essentially forces the compiler to compare the types of
the actual Rust function and the 'bindgen'-processed C signature.
These cases are rare so far. In the future, we may consider
introducing another tool, 'cbindgen', to generate C headers
automatically. Even then, having these functions explicitly marked
may be a good idea anyway.
- Enable the 'raw_ref_op' Rust feature: it is already stable, and
allows us to use the new '&raw' syntax, avoiding a couple macros.
After everyone has migrated, we will disallow the macros.
- Pass the correct target to 'bindgen' on Usermode Linux.
- Fix 'rusttest' build in macOS.
'kernel' crate:
- New 'hrtimer' module: add support for setting up intrusive timers
without allocating when starting the timer. Add support for
'Pin<Box<_>>', 'Arc<_>', 'Pin<&_>' and 'Pin<&mut _>' as pointer
types for use with timer callbacks. Add support for setting clock
source and timer mode.
- New 'dma' module: add a simple DMA coherent allocator abstraction
and a test sample driver.
- 'list' module: make the linked list 'Cursor' point between
elements, rather than at an element, which is more convenient to us
and allows for cursors to empty lists; and document it with
examples of how to perform common operations with the provided
methods.
- 'str' module: implement a few traits for 'BStr' as well as the
'strip_prefix()' method.
- 'sync' module: add 'Arc::as_ptr'.
- 'alloc' module: add 'Box::into_pin'.
- 'error' module: extend the 'Result' documentation, including a few
examples on different ways of handling errors, a warning about
using methods that may panic, and links to external documentation.
'macros' crate:
- 'module' macro: add the 'authors' key to support multiple authors.
The original key will be kept until everyone has migrated.
Documentation:
- Add error handling sections.
MAINTAINERS:
- Add Danilo Krummrich as reviewer of the Rust "subsystem".
- Add 'RUST [PIN-INIT]' entry with Benno Lossin as maintainer. It has
its own sub-tree.
- Add sub-tree for 'RUST [ALLOC]'.
- Add 'DMA MAPPING HELPERS DEVICE DRIVER API [RUST]' entry with
Abdiel Janulgue as primary maintainer. It will go through the
sub-tree of the 'RUST [ALLOC]' entry.
- Add 'HIGH-RESOLUTION TIMERS [RUST]' entry with Andreas Hindborg as
maintainer. It has its own sub-tree.
And a few other cleanups and improvements"
* tag 'rust-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: (71 commits)
rust: dma: add `Send` implementation for `CoherentAllocation`
rust: macros: fix `make rusttest` build on macOS
rust: block: refactor to use `&raw mut`
rust: enable `raw_ref_op` feature
rust: uaccess: name the correct function
rust: rbtree: fix comments referring to Box instead of KBox
rust: hrtimer: add maintainer entry
rust: hrtimer: add clocksource selection through `ClockId`
rust: hrtimer: add `HrTimerMode`
rust: hrtimer: implement `HrTimerPointer` for `Pin<Box<T>>`
rust: alloc: add `Box::into_pin`
rust: hrtimer: implement `UnsafeHrTimerPointer` for `Pin<&mut T>`
rust: hrtimer: implement `UnsafeHrTimerPointer` for `Pin<&T>`
rust: hrtimer: add `hrtimer::ScopedHrTimerPointer`
rust: hrtimer: add `UnsafeHrTimerPointer`
rust: hrtimer: allow timer restart from timer handler
rust: str: implement `strip_prefix` for `BStr`
rust: str: implement `AsRef<BStr>` for `[u8]` and `BStr`
rust: str: implement `Index` for `BStr`
rust: str: implement `PartialEq` for `BStr`
...
Do not emit `#[link_section = ".modinfo"]` on macOS (i.e. when building userspace tests); .modinfo is not a legal section specifier in mach-o. Before this change tests failed to compile: ---- ../rust/macros/lib.rs - module (line 66) stdout ---- rustc-LLVM ERROR: Global variable '_ZN8rust_out13__module_init13__module_init27__MY_DEVICE_DRIVER_MODULE_017h141f80536770e0d4E' has an invalid section specifier '.modinfo': mach-o section specifier requires a segment and section separated by a comma. Couldn't compile the test. ---- ../rust/macros/lib.rs - module (line 33) stdout ---- rustc-LLVM ERROR: Global variable '_ZN8rust_out13__module_init13__module_init20__MY_KERNEL_MODULE_017h5d79189564b41e07E' has an invalid section specifier '.modinfo': mach-o section specifier requires a segment and section separated by a comma. Couldn't compile the test. Signed-off-by: Tamir Duberstein <tamird@gmail.com> Link: https://lore.kernel.org/r/20250210-macros-section-v2-1-3bb9ff44b969@gmail.com Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Rename relative paths inside of the crate to still refer to the same
items, also rename paths inside of the kernel crate and adjust the build
system to build the crate.
[ Remove the `expect` (and thus the `lint_reasons` feature) since
the tree now uses `quote!` from `rust/macros/export.rs`. Remove the
`TokenStream` import removal, since it is now used as well.
In addition, temporarily (i.e. just for this commit) use an `--extern
force:alloc` to prevent an unknown `new_uninit` error in the `rustdoc`
target. For context, please see a similar case in:
https://lore.kernel.org/lkml/20240422090644.525520-1-ojeda@kernel.org/
And adjusted the message above. - Miguel ]
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Fiona Behrens <me@kloenk.dev>
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20250308110339.2997091-16-benno.lossin@proton.me
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
In the `module!` macro, the `author` field is currently of type `String`.
Since modules can have multiple authors, this limitation prevents
specifying more than one.
Add an `authors` field as `Option<Vec<String>>` to allow creating
modules with multiple authors, and change the documentation and all
current users to use it. Eventually, the single `author` field may
be removed.
[ The `modinfo` key needs to still be `author`; otherwise, tooling
may not work properly, e.g.:
$ modinfo --author samples/rust/rust_print.ko
Rust for Linux Contributors
I have also kept the original `author` field (undocumented), so
that we can drop it more easily in a kernel cycle or two.
- Miguel ]
Suggested-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://github.com/Rust-for-Linux/linux/issues/244
Reviewed-by: Charalampos Mitrodimas <charmitro@posteo.net>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Signed-off-by: Guilherme Giacomo Simoes <trintaeoitogc@gmail.com>
Link: https://lore.kernel.org/r/20250309175712.845622-2-trintaeoitogc@gmail.com
[ Fixed `modinfo` key. Kept `author` field. Reworded message
accordingly. Updated my email. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
The `LocalModule` type is the type of the module created by `module!`, `module_pci_driver!`, `module_platform_driver!`, etc. Since the exact type of the module is sometimes generated on the fly by the listed macros, provide an alias. This is first used by the `module_firmware!` macro. Acked-by: Miguel Ojeda <ojeda@kernel.org> Suggested-by: Alice Ryhl <aliceryhl@google.com> Link: https://lore.kernel.org/r/20250306222336.23482-2-dakr@kernel.org Signed-off-by: Danilo Krummrich <dakr@kernel.org>
In order to access static metadata of a Rust kernel module, add the `ModuleMetadata` trait. In particular, this trait provides the name of a Rust kernel module as specified by the `module!` macro. Signed-off-by: Danilo Krummrich <dakr@kernel.org> Tested-by: Dirk Behme <dirk.behme@de.bosch.com> Tested-by: Fabien Parent <fabien.parent@linaro.org> Link: https://lore.kernel.org/r/20241219170425.12036-2-dakr@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull char/misc/IIO/whatever driver subsystem updates from Greg KH:
"Here is the 'big and hairy' char/misc/iio and other small driver
subsystem updates for 6.13-rc1.
Loads of things in here, and even a fun merge conflict!
- rust misc driver bindings and other rust changes to make misc
drivers actually possible.
I think this is the tipping point, expect to see way more rust
drivers going forward now that these bindings are present. Next
merge window hopefully we will have pci and platform drivers
working, which will fully enable almost all driver subsystems to
start accepting (or at least getting) rust drivers.
This is the end result of a lot of work from a lot of people,
congrats to all of them for getting this far, you've proved many of
us wrong in the best way possible, working code :)
- IIO driver updates, too many to list individually, that subsystem
keeps growing and growing...
- Interconnect driver updates
- nvmem driver updates
- pwm driver updates
- platform_driver::remove() fixups, loads of them
- counter driver updates
- misc driver updates (keba?)
- binder driver updates and fixes
- loads of other small char/misc/etc driver updates and additions,
full details in the shortlog.
All of these have been in linux-next for a while, with no other
reported issues other than that merge conflict"
* tag 'char-misc-6.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (401 commits)
mei: vsc: Fix typo "maintstepping" -> "mainstepping"
firmware: Switch back to struct platform_driver::remove()
misc: isl29020: Fix the wrong format specifier
scripts/tags.sh: Don't tag usages of DEFINE_MUTEX
fpga: Switch back to struct platform_driver::remove()
mei: vsc: Improve error logging in vsc_identify_silicon()
mei: vsc: Do not re-enable interrupt from vsc_tp_reset()
dt-bindings: spmi: qcom,x1e80100-spmi-pmic-arb: Add SAR2130P compatible
dt-bindings: spmi: spmi-mtk-pmif: Add compatible for MT8188
spmi: pmic-arb: fix return path in for_each_available_child_of_node()
iio: Move __private marking before struct element priv in struct iio_dev
docs: iio: ad7380: add adaq4370-4 and adaq4380-4
iio: adc: ad7380: add support for adaq4370-4 and adaq4380-4
iio: adc: ad7380: use local dev variable to shorten long lines
iio: adc: ad7380: fix oversampling formula
dt-bindings: iio: adc: ad7380: add adaq4370-4 and adaq4380-4 compatible parts
bus: mhi: host: pci_generic: Use pcim_iomap_region() to request and map MHI BAR
bus: mhi: host: Switch trace_mhi_gen_tre fields to native endian
misc: atmel-ssc: Use of_property_present() for non-boolean properties
misc: keba: Add hardware dependency
...