Commit 4e6b5b8a authored by Benno Lossin's avatar Benno Lossin Committed by Miguel Ojeda
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rust: sync: fix safety comment for `static_lock_class` 



The safety comment mentions lockdep -- which from a Rust perspective
isn't important -- and doesn't mention the real reason for why it's
sound to create `LockClassKey` as uninitialized memory.

Signed-off-by: default avatarBenno Lossin <lossin@kernel.org>
Reviewed-by: default avatarAlice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250520231714.323931-1-lossin@kernel.org


Signed-off-by: default avatarMiguel Ojeda <ojeda@kernel.org>
parent 28753212

rust/kernel/sync.rs

+5 −2
Original line number Diff line number Diff line
@@ -95,8 +95,11 @@ fn drop(self: Pin<&mut Self>) { 
macro_rules! static_lock_class {

    () => {{

        static CLASS: $crate::sync::LockClassKey =

            // SAFETY: lockdep expects uninitialized memory when it's handed a statically allocated

            // lock_class_key

            // Lockdep expects uninitialized memory when it's handed a statically allocated `struct

            // lock_class_key`.

            //

            // SAFETY: `LockClassKey` transparently wraps `Opaque` which permits uninitialized

            // memory.

            unsafe { ::core::mem::MaybeUninit::uninit().assume_init() };

        $crate::prelude::Pin::static_ref(&CLASS)

    }};