The patch below does not apply to the 6.6-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y git checkout FETCH_HEAD git cherry-pick -x 966944f3711665db13e214fef6d02982c49bb972 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2025031632-divorcee-duly-868e@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 966944f3711665db13e214fef6d02982c49bb972 Mon Sep 17 00:00:00 2001 From: Mitchell Levy levymitchell0@gmail.com Date: Fri, 7 Mar 2025 15:27:00 -0800 Subject: [PATCH] rust: lockdep: Remove support for dynamically allocated LockClassKeys
Currently, dynamically allocated LockCLassKeys can be used from the Rust side without having them registered. This is a soundness issue, so remove them.
Fixes: 6ea5aa08857a ("rust: sync: introduce `LockClassKey`") Suggested-by: Alice Ryhl aliceryhl@google.com Signed-off-by: Mitchell Levy levymitchell0@gmail.com Signed-off-by: Boqun Feng boqun.feng@gmail.com Signed-off-by: Ingo Molnar mingo@kernel.org Reviewed-by: Benno Lossin benno.lossin@proton.me Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20250307232717.1759087-11-boqun.feng@gmail.com
diff --git a/rust/kernel/sync.rs b/rust/kernel/sync.rs index 3498fb344dc9..16eab9138b2b 100644 --- a/rust/kernel/sync.rs +++ b/rust/kernel/sync.rs @@ -30,28 +30,20 @@ unsafe impl Sync for LockClassKey {}
impl LockClassKey { - /// Creates a new lock class key. - pub const fn new() -> Self { - Self(Opaque::uninit()) - } - pub(crate) fn as_ptr(&self) -> *mut bindings::lock_class_key { self.0.get() } }
-impl Default for LockClassKey { - fn default() -> Self { - Self::new() - } -} - /// Defines a new static lock class and returns a pointer to it. #[doc(hidden)] #[macro_export] macro_rules! static_lock_class { () => {{ - static CLASS: $crate::sync::LockClassKey = $crate::sync::LockClassKey::new(); + static CLASS: $crate::sync::LockClassKey = + // SAFETY: lockdep expects uninitialized memory when it's handed a statically allocated + // lock_class_key + unsafe { ::core::mem::MaybeUninit::uninit().assume_init() }; &CLASS }}; }