kernel/linux.git/rust/macros/kunit.rs, branch v7.1-rc5

rust: macros: simplify code using `feature(extract_if)`

2026-04-07T08:00:24+00:00

`feature(extract_if)` [1] was stabilized in Rust 1.87.0 [2], and the last significant change happened in Rust 1.85.0 [3] when the range parameter was added. That is, with our new minimum version, we can start using the feature. Thus simplify the code using the feature and remove the TODO comment. Suggested-by: Gary Guo Link: https://lore.kernel.org/rust-for-linux/DHHVSX66206Y.3E7I9QUNTCJ8I@garyguo.net/ Link: https://github.com/rust-lang/rust/issues/43244 [1] Link: https://github.com/rust-lang/rust/pull/137109 [2] Link: https://github.com/rust-lang/rust/pull/133265 [3] Link: https://patch.msgid.link/20260405235309.418950-16-ojeda@kernel.org Reviewed-by: Tamir Duberstein Signed-off-by: Miguel Ojeda

rust: kunit: use `pin_init::zeroed` instead of custom null value

2026-01-28T12:44:17+00:00

The last null element can be created (constly) using `pin_init::zeroed`, so prefer to use it instead of adding a custom way of building it. Reviewed-by: Tamir Duberstein Reviewed-by: Benno Lossin Signed-off-by: Gary Guo Reviewed-by: David Gow Link: https://patch.msgid.link/20260112170919.1888584-12-gary@kernel.org Signed-off-by: Miguel Ojeda

rust: macros: convert `#[kunit_tests]` macro to use `syn`

2026-01-28T12:43:36+00:00

Make use of `syn` to parse the module structurally and thus improve the robustness of parsing. String interpolation is avoided by generating tokens directly using `quote!`. Reviewed-by: Tamir Duberstein Signed-off-by: Gary Guo Reviewed-by: Benno Lossin Reviewed-by: David Gow Link: https://patch.msgid.link/20260112170919.1888584-9-gary@kernel.org [ Pass C string to match commit 6c37b6841a92 ("rust: kunit: replace `kernel::c_str!` with C-Strings"). - Miguel ] Signed-off-by: Miguel Ojeda

rust: macros: use `quote!` from vendored crate

2026-01-27T23:55:24+00:00

With `quote` crate now vendored in the kernel, we can remove our custom `quote!` macro implementation and just rely on that crate instead. The `quote` crate uses types from the `proc-macro2` library so we also update to use that, and perform conversion in the top-level lib.rs. Clippy complains about unnecessary `.to_string()` as `proc-macro2` provides additional `PartialEq` impl, so they are removed. Reviewed-by: Tamir Duberstein Reviewed-by: Benno Lossin Signed-off-by: Gary Guo Acked-by: David Gow # for kunit Link: https://patch.msgid.link/20260112170919.1888584-3-gary@kernel.org Signed-off-by: Miguel Ojeda

rust: kunit: replace `kernel::c_str!` with C-Strings

2026-01-19T00:13:23+00:00

C-String literals were added in Rust 1.77. Replace instances of `kernel::c_str!` with C-String literals where possible. Acked-by: Greg Kroah-Hartman Reviewed-by: Alice Ryhl Reviewed-by: Benno Lossin Signed-off-by: Tamir Duberstein Reviewed-by: David Gow Link: https://patch.msgid.link/20251222-cstr-kunit-v1-1-39d999672f35@gmail.com Signed-off-by: Miguel Ojeda

rust: kunit: allow `cfg` on `test`s

2025-09-16T14:26:56+00:00

The `kunit_test` proc macro only checks for the `test` attribute immediately preceding a `fn`. If the function is disabled via a `cfg`, the generated code would result in a compile error referencing a non-existent function [1]. This collects attributes and specifically cherry-picks `cfg` attributes to be duplicated inside KUnit wrapper functions such that a test function disabled via `cfg` compiles and is marked as skipped in KUnit correctly. Link: https://lore.kernel.org/r/20250916021259.115578-1-ent3rm4n@gmail.com Link: https://lore.kernel.org/rust-for-linux/CANiq72==48=69hYiDo1321pCzgn_n1_jg=ez5UYXX91c+g5JVQ@mail.gmail.com/ [1] Closes: https://github.com/Rust-for-Linux/linux/issues/1185 Suggested-by: Miguel Ojeda Suggested-by: David Gow Signed-off-by: Kaibo Ma Reviewed-by: David Gow Signed-off-by: Shuah Khan

rust: kunit: support checked `-> Result`s in KUnit `#[test]`s

2025-05-27T18:09:59+00:00

Currently, return values of KUnit `#[test]` functions are ignored. Thus introduce support for `-> Result` functions by checking their returned values. At the same time, require that test functions return `()` or `Result`, which should avoid mistakes, especially with non-`#[must_use]` types. Other types can be supported in the future if needed. With this, a failing test like: #[test] fn my_test() -> Result { f()?; Ok(()) } will output: [ 3.744214] KTAP version 1 [ 3.744287] # Subtest: my_test_suite [ 3.744378] # speed: normal [ 3.744399] 1..1 [ 3.745817] # my_test: ASSERTION FAILED at rust/kernel/lib.rs:321 [ 3.745817] Expected is_test_result_ok(my_test()) to be true, but is false [ 3.747152] # my_test.speed: normal [ 3.747199] not ok 1 my_test [ 3.747345] not ok 4 my_test_suite Reviewed-by: David Gow Acked-by: Danilo Krummrich Link: https://lore.kernel.org/r/20250502215133.1923676-3-ojeda@kernel.org [ Used `::kernel` for paths. - Miguel ] Signed-off-by: Miguel Ojeda

rust: kunit: support KUnit-mapped `assert!` macros in `#[test]`s

2025-05-27T18:07:09+00:00

The KUnit `#[test]` support that landed recently is very basic and does not map the `assert*!` macros into KUnit like the doctests do, so they panic at the moment. Thus implement the custom mapping in a similar way to doctests, reusing the infrastructure there. In Rust 1.88.0, the `file()` method in `Span` may be stable [1]. However, it was changed recently (from `SourceFile`), so we need to do something different in previous versions. Thus create a helper for it and use it to get the path. With this, a failing test suite like: #[kunit_tests(my_test_suite)] mod tests { use super::*; #[test] fn my_first_test() { assert_eq!(42, 43); } #[test] fn my_second_test() { assert!(42 >= 43); } } will properly map back to KUnit, printing something like: [ 1.924325] KTAP version 1 [ 1.924421] # Subtest: my_test_suite [ 1.924506] # speed: normal [ 1.924525] 1..2 [ 1.926385] # my_first_test: ASSERTION FAILED at rust/kernel/lib.rs:251 [ 1.926385] Expected 42 == 43 to be true, but is false [ 1.928026] # my_first_test.speed: normal [ 1.928075] not ok 1 my_first_test [ 1.928723] # my_second_test: ASSERTION FAILED at rust/kernel/lib.rs:256 [ 1.928723] Expected 42 >= 43 to be true, but is false [ 1.929834] # my_second_test.speed: normal [ 1.929868] not ok 2 my_second_test [ 1.930032] # my_test_suite: pass:0 fail:2 skip:0 total:2 [ 1.930153] # Totals: pass:0 fail:2 skip:0 total Link: https://github.com/rust-lang/rust/pull/140514 [1] Reviewed-by: David Gow Acked-by: Danilo Krummrich Link: https://lore.kernel.org/r/20250502215133.1923676-2-ojeda@kernel.org [ Required `KUNIT=y` like for doctests. Used the `cfg_attr` from the TODO comment and clarified its comment now that the stabilization is in beta and thus quite likely stable in Rust 1.88.0. Simplified the `new_body` code by introducing a new variable. Added `#[allow(clippy::incompatible_msrv)]`. - Miguel ] Signed-off-by: Miguel Ojeda

rust: use absolute paths in macros referencing core and kernel

2025-05-22T22:12:14+00:00

Macros and auto-generated code should use absolute paths, `::core::...` and `::kernel::...`, for core and kernel references. This prevents issues where user-defined modules named `core` or `kernel` could be picked up instead of the `core` or `kernel` crates. Thus clean some references up. Suggested-by: Benno Lossin Closes: https://github.com/Rust-for-Linux/linux/issues/1150 Signed-off-by: Igor Korotin Reviewed-by: Benno Lossin Acked-by: Greg Kroah-Hartman Link: https://lore.kernel.org/r/20250519164615.3310844-1-igor.korotin.linux@gmail.com [ Applied `rustfmt`. Reworded slightly. - Miguel ] Signed-off-by: Miguel Ojeda

rust: clean Rust 1.88.0's `clippy::uninlined_format_args` lint

2025-05-06T22:11:47+00:00

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 Reviewed-by: Tamir Duberstein Reviewed-by: Alice Ryhl Link: https://lore.kernel.org/r/20250502140237.1659624-6-ojeda@kernel.org Signed-off-by: Miguel Ojeda