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Index: sys/sys/buf_ring.h
===================================================================
--- sys/sys/buf_ring.h
+++ sys/sys/buf_ring.h
@@ -319,6 +319,20 @@
if (br->br_cons_head == br->br_prod_tail)
return (NULL);
+#if defined(__arm__) || defined(__aarch64__)
+ /*
+ * The barrier is required there on ARM and ARM64 to ensure, that
+ * br->br_ring[br->br_cons_head] will not be fetched before the above
+ * condition is checked.
+ * Without the barrier, it is possible, that buffer will be fetched
+ * before the enqueue will put mbuf into br, then, in the meantime, the
+ * enqueue will update the array and the br_prod_tail, and the
+ * conditional check will be true, so we will return previously fetched
+ * (and invalid) buffer.
+ */
+ atomic_thread_fence_acq();
+#endif
+
#ifdef DEBUG_BUFRING
/*
* Single consumer, i.e. cons_head will not move while we are

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