--- glibc-2.27/nptl/pthread_mutex_lock.c~	2018-02-01 16:17:18.000000000 +0000
+++ glibc-2.27/nptl/pthread_mutex_lock.c	2018-05-15 14:19:00.864190585 +0000
@@ -133,7 +133,13 @@
 		  LLL_MUTEX_LOCK (mutex);
 		  break;
 		}
-	      atomic_spin_nop ();
+		/* MO read while spinning */
+		do
+		  {
+		    atomic_spin_nop ();
+		  }
+		while (atomic_load_relaxed (&mutex->__data.__lock) != 0 &&
+			++cnt < max_cnt);
 	    }
 	  while (LLL_MUTEX_TRYLOCK (mutex) != 0);