Merge pull request torvalds#612 from wedsonaf/revocable-mutex-drop

rust: fix drop in `RevocableMutex`

rust/kernel/sync/revocable_mutex.rs

@@ -11,7 +11,6 @@ use core::{
  mem::ManuallyDrop,
  ops::{Deref, DerefMut},
  pin::Pin,
- ptr::drop_in_place,
 };
 
 /// The state within a `RevocableMutex` that is protected by a mutex.
@@ -138,10 +137,11 @@ impl<T: ?Sized> RevocableMutex<T> {
  return;
  }
 
- // SAFETY: We know `inner.data` is valid because `is_available` is set to true. We'll drop
- // it here and set it to false so it isn't dropped again.
- unsafe { drop_in_place(&mut inner.data) };
  inner.is_available = false;
+
+ // SAFETY: We know `inner.data` is valid because `is_available` was true. We'll drop it
+ // here, and given that we set `is_available` to false above, it won't be dropped again.
+ unsafe { ManuallyDrop::drop(&mut inner.data) };
  }
 }