mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-02-18 01:20:26 -05:00
d6763e0abb
When a reference appears in a function argument, the reference is assumed to be valid for the entire duration of that function call; this is called a stack protector [1]. Because of that, custom pointer types whose destructor may invalidate the pointee (i.e. they are more similar to Box<T> than &T) cannot internally use a reference, and must instead use a raw pointer. This issue is something that is often missed during unsafe review. For examples, see [2] and [3]. To ensure that people don't try to simplify RevocableGuard by changing the raw pointer to a reference, add a comment to that effect. Link: https://perso.crans.org/vanille/treebor/protectors.html [1] Link: https://users.rust-lang.org/t/unsafe-code-review-semi-owning-weak-rwlock-t-guard/95706 [2] Link: https://lore.kernel.org/all/aEqdur4JTFa1V20U@google.com/ [3] Signed-off-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Benno Lossin <lossin@kernel.org> Link: https://lore.kernel.org/r/20250612-revocable-ptr-comment-v1-1-db36785877f6@google.com [ Adjusted title. - Miguel ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>