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diff --git a/tools/memory-model/litmus-tests/MP+fencewmbonceonce+fencermbonceonce.litmus b/tools/memory-model/litmus-tests/MP+fencewmbonceonce+fencermbonceonce.litmus
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+C MP+fencewmbonceonce+fencermbonceonce
+
+(*
+ * Result: Never
+ *
+ * This litmus test demonstrates that smp_wmb() and smp_rmb() provide
+ * sufficient ordering for the message-passing pattern. However, it
+ * is usually better to use smp_store_release() and smp_load_acquire().
+ *)
+
+{}
+
+P0(int *buf, int *flag) // Producer
+{
+ WRITE_ONCE(*buf, 1);
+ smp_wmb();
+ WRITE_ONCE(*flag, 1);
+}
+
+P1(int *buf, int *flag) // Consumer
+{
+ int r0;
+ int r1;
+
+ r0 = READ_ONCE(*flag);
+ smp_rmb();
+ r1 = READ_ONCE(*buf);
+}
+
+exists (1:r0=1 /\ 1:r1=0) (* Bad outcome. *)