Cc: Peter Zijlstra <[email protected]>
Cc: Waiman Long <[email protected]>
Cc: Johannes Berg <[email protected]>
Signed-off-by: Bart Van Assche <[email protected]>
---
kernel/locking/lockdep.c | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index f95c1beddc28..2685b2265f6e 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -738,6 +738,17 @@ static bool assign_lock_key(struct lockdep_map *lock)
{
unsigned long can_addr, addr = (unsigned long)lock;
+#ifdef __KERNEL__
+ /*
+ * lockdep_free_key_range() assumes that struct lock_class_key
+ * objects do not overlap. Since we use the address of lock
+ * objects as class key for static objects, check whether the
+ * size of lock_class_key objects does not exceed the size of
+ * the smallest lock object.
+ */
+ BUILD_BUG_ON(sizeof(struct lock_class_key) > sizeof(raw_spinlock_t));
+#endif
+
if (__is_kernel_percpu_address(addr, &can_addr))
lock->key = (void *)can_addr;
else if (__is_module_percpu_address(addr, &can_addr))
--
2.20.0.rc2.403.gdbc3b29805-goog
