diff --git a/security/security.c b/security/security.c
index 7272bbea05cb..4564a0a1e4ef 100644
--- a/security/security.c
+++ b/security/security.c
@@ -3048,6 +3048,8 @@ int security_file_fcntl(struct file *file, unsigned int cmd, unsigned long arg)
  * Save owner security information (typically from current->security) in
  * file->f_security for later use by the send_sigiotask hook.
  *
+ * This hook is called with file->f_owner.lock held.
+ *
  * Return: Returns 0 on success.
  */
 void security_file_set_fowner(struct file *file)