D46153.diff
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	diff --git a/sys/sys/buf_ring.h b/sys/sys/buf_ring.h
	--- a/sys/sys/buf_ring.h
	+++ b/sys/sys/buf_ring.h
	@@ -177,37 +177,8 @@
	uint32_t prod_tail, mask;
	void *buf;

	- /*
	- * This is a workaround to allow using buf_ring on ARM and ARM64.
	- * ARM64TODO: Fix buf_ring in a generic way.
	- * REMARKS: It is suspected that br_cons_head does not require
	- * load_acq operation, but this change was extensively tested
	- * and confirmed it's working. To be reviewed once again in
	- * FreeBSD-12.
	- *
	- * Preventing following situation:
	-
	- * Core(0) - buf_ring_enqueue() Core(1) - buf_ring_dequeue_sc()
	- * ----------------------------------------- ----------------------------------------------
	- *
	- * cons_head = br->br_cons_head;
	- * atomic_cmpset_acq_32(&br->br_prod_head, ...));
	- * buf = br->br_ring[cons_head]; <see <1>>
	- * br->br_ring[prod_head] = buf;
	- * atomic_store_rel_32(&br->br_prod_tail, ...);
	- * prod_tail = br->br_prod_tail;
	- * if (cons_head == prod_tail)
	- * return (NULL);
	- * <condition is false and code uses invalid(old) buf>`
	- *
	- * <1> Load (on core 1) from br->br_ring[cons_head] can be reordered (speculative readed) by CPU.
	- */
	mask = br->br_cons_mask;
	-#if defined(__arm__) \|\| defined(__aarch64__)
	- cons_head = atomic_load_acq_32(&br->br_cons_head);
	-#else
	cons_head = br->br_cons_head;
	-#endif
	prod_tail = atomic_load_acq_32(&br->br_prod_tail);

	cons_next = cons_head + 1;