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diff --git a/Documentation/litmus-tests/locking/RM-fixed.litmus b/Documentation/litmus-tests/locking/RM-fixed.litmus
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+C RM-fixed
+
+(*
+ * Result: Never
+ *
+ * This litmus test demonstrates that the old "roach motel" approach
+ * to locking, where code can be freely moved into critical sections,
+ * cannot be used in the Linux kernel.
+ *)
+
+{
+ int x;
+ atomic_t y;
+}
+
+P0(int *x, atomic_t *y, spinlock_t *lck)
+{
+ int r2;
+
+ spin_lock(lck);
+ r2 = atomic_inc_return(y);
+ WRITE_ONCE(*x, 1);
+ spin_unlock(lck);
+}
+
+P1(int *x, atomic_t *y, spinlock_t *lck)
+{
+ int r0;
+ int r1;
+ int r2;
+
+ r0 = READ_ONCE(*x);
+ r1 = READ_ONCE(*x);
+ spin_lock(lck);
+ r2 = atomic_inc_return(y);
+ spin_unlock(lck);
+}
+
+locations [x;0:r2;1:r0;1:r1;1:r2]
+filter (1:r0=0 /\ 1:r1=1)
+exists (1:r2=1)