Commit c28bfe76 authored Sep 04, 2024 by Miguel Ojeda

rust: enable `clippy::unnecessary_safety_comment` lint

In Rust 1.67.0, Clippy added the `unnecessary_safety_comment` lint [1],
which is the "inverse" of `undocumented_unsafe_blocks`: it finds places
where safe code has a `// SAFETY` comment attached.

The lint currently finds 3 places where we had such mistakes, thus it
seems already quite useful.

Thus clean those and enable it.

Link: https://rust-lang.github.io/rust-clippy/master/index.html#/unnecessary_safety_comment

 [1]
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Trevor Gross <tmgross@umich.edu>
Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com>
Tested-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/r/20240904204347.168520-6-ojeda@kernel.org


Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

parent db4f72c9

Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -458,6 +458,7 @@ export rust_common_flags := --edition=2021 \
		-Wclippy::needless_continue \
		-Wclippy::no_mangle_with_rust_abi \
		-Wclippy::undocumented_unsafe_blocks \
		-Wclippy::unnecessary_safety_comment \
		-Wrustdoc::missing_crate_level_docs

		KBUILD_HOSTCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) \

rust/kernel/sync/arc.rs

+1 −1

Original line number	Diff line number	Diff line
		@@ -341,7 +341,7 @@ fn into_foreign(self) -> *const core::ffi::c_void {
		}

		unsafe fn borrow<'a>(ptr: *const core::ffi::c_void) -> ArcBorrow<'a, T> {
		// SAFETY: By the safety requirement of this function, we know that `ptr` came from
		// By the safety requirement of this function, we know that `ptr` came from
		// a previous call to `Arc::into_foreign`.
		let inner = NonNull::new(ptr as *mut ArcInner<T>).unwrap();

rust/kernel/workqueue.rs

+2 −2

Original line number	Diff line number	Diff line
		@@ -526,7 +526,7 @@ unsafe impl<T, const ID: u64> WorkItemPointer<ID> for Arc<T>
		T: HasWork<T, ID>,
		{
		unsafe extern "C" fn run(ptr: *mut bindings::work_struct) {
		// SAFETY: The `__enqueue` method always uses a `work_struct` stored in a `Work<T, ID>`.
		// The `__enqueue` method always uses a `work_struct` stored in a `Work<T, ID>`.
		let ptr = ptr as *mut Work<T, ID>;
		// SAFETY: This computes the pointer that `__enqueue` got from `Arc::into_raw`.
		let ptr = unsafe { T::work_container_of(ptr) };
		@@ -573,7 +573,7 @@ unsafe impl<T, const ID: u64> WorkItemPointer<ID> for Pin<Box<T>>
		T: HasWork<T, ID>,
		{
		unsafe extern "C" fn run(ptr: *mut bindings::work_struct) {
		// SAFETY: The `__enqueue` method always uses a `work_struct` stored in a `Work<T, ID>`.
		// The `__enqueue` method always uses a `work_struct` stored in a `Work<T, ID>`.
		let ptr = ptr as *mut Work<T, ID>;
		// SAFETY: This computes the pointer that `__enqueue` got from `Arc::into_raw`.
		let ptr = unsafe { T::work_container_of(ptr) };