diff --git a/drivers/event/octeontx/ssovf_evdev_selftest.c b/drivers/event/octeontx/ssovf_evdev_selftest.c
index 7a2b7ded25..528f99dd84 100644
--- a/drivers/event/octeontx/ssovf_evdev_selftest.c
+++ b/drivers/event/octeontx/ssovf_evdev_selftest.c
@@ -300,7 +300,7 @@ inject_events(uint32_t flow_id, uint8_t event_type, uint8_t sub_event_type,
 		m = rte_pktmbuf_alloc(eventdev_test_mempool);
 		RTE_TEST_ASSERT_NOT_NULL(m, "mempool alloc failed");
 
-		m->seqn = i;
+		*rte_event_pmd_selftest_seqn(m) = i;
 		update_event_and_validation_attr(m, &ev, flow_id, event_type,
 			sub_event_type, sched_type, queue, port);
 		rte_event_enqueue_burst(evdev, port, &ev, 1);
@@ -320,7 +320,8 @@ check_excess_events(uint8_t port)
 		valid_event = rte_event_dequeue_burst(evdev, port, &ev, 1, 0);
 
 		RTE_TEST_ASSERT_SUCCESS(valid_event,
-				"Unexpected valid event=%d", ev.mbuf->seqn);
+			"Unexpected valid event=%d",
+			*rte_event_pmd_selftest_seqn(ev.mbuf));
 	}
 	return 0;
 }
@@ -425,8 +426,9 @@ static int
 validate_simple_enqdeq(uint32_t index, uint8_t port, struct rte_event *ev)
 {
 	RTE_SET_USED(port);
-	RTE_TEST_ASSERT_EQUAL(index, ev->mbuf->seqn, "index=%d != seqn=%d",
-			index, ev->mbuf->seqn);
+	RTE_TEST_ASSERT_EQUAL(index, *rte_event_pmd_selftest_seqn(ev->mbuf),
+		"index=%d != seqn=%d", index,
+		*rte_event_pmd_selftest_seqn(ev->mbuf));
 	return 0;
 }
 
@@ -509,10 +511,10 @@ validate_queue_priority(uint32_t index, uint8_t port, struct rte_event *ev)
 
 	expected_val += ev->queue_id;
 	RTE_SET_USED(port);
-	RTE_TEST_ASSERT_EQUAL(ev->mbuf->seqn, expected_val,
-	"seqn=%d index=%d expected=%d range=%d nb_queues=%d max_event=%d",
-			ev->mbuf->seqn, index, expected_val, range,
-			queue_count, MAX_EVENTS);
+	RTE_TEST_ASSERT_EQUAL(*rte_event_pmd_selftest_seqn(ev->mbuf), expected_val,
+		"seqn=%d index=%d expected=%d range=%d nb_queues=%d max_event=%d",
+		*rte_event_pmd_selftest_seqn(ev->mbuf), index, expected_val, range,
+		queue_count, MAX_EVENTS);
 	return 0;
 }
 
@@ -537,7 +539,7 @@ test_multi_queue_priority(void)
 		m = rte_pktmbuf_alloc(eventdev_test_mempool);
 		RTE_TEST_ASSERT_NOT_NULL(m, "mempool alloc failed");
 
-		m->seqn = i;
+		*rte_event_pmd_selftest_seqn(m) = i;
 		queue = i % queue_count;
 		update_event_and_validation_attr(m, &ev, 0, RTE_EVENT_TYPE_CPU,
 			0, RTE_SCHED_TYPE_PARALLEL, queue, 0);
@@ -904,7 +906,7 @@ worker_flow_based_pipeline(void *arg)
 			ev.op = RTE_EVENT_OP_FORWARD;
 			rte_event_enqueue_burst(evdev, port, &ev, 1);
 		} else if (ev.sub_event_type == 1) { /* Events from stage 1*/
-			if (seqn_list_update(ev.mbuf->seqn) == 0) {
+			if (seqn_list_update(*rte_event_pmd_selftest_seqn(ev.mbuf)) == 0) {
 				rte_pktmbuf_free(ev.mbuf);
 				rte_atomic32_sub(total_events, 1);
 			} else {
@@ -939,7 +941,7 @@ test_multiport_flow_sched_type_test(uint8_t in_sched_type,
 		return 0;
 	}
 
-	/* Injects events with m->seqn=0 to total_events */
+	/* Injects events with a 0 sequence number to total_events */
 	ret = inject_events(
 		0x1 /*flow_id */,
 		RTE_EVENT_TYPE_CPU /* event_type */,
@@ -1059,7 +1061,7 @@ worker_group_based_pipeline(void *arg)
 			ev.op = RTE_EVENT_OP_FORWARD;
 			rte_event_enqueue_burst(evdev, port, &ev, 1);
 		} else if (ev.queue_id == 1) { /* Events from stage 1(group 1)*/
-			if (seqn_list_update(ev.mbuf->seqn) == 0) {
+			if (seqn_list_update(*rte_event_pmd_selftest_seqn(ev.mbuf)) == 0) {
 				rte_pktmbuf_free(ev.mbuf);
 				rte_atomic32_sub(total_events, 1);
 			} else {
@@ -1101,7 +1103,7 @@ test_multiport_queue_sched_type_test(uint8_t in_sched_type,
 		return 0;
 	}
 
-	/* Injects events with m->seqn=0 to total_events */
+	/* Injects events with a 0 sequence number to total_events */
 	ret = inject_events(
 		0x1 /*flow_id */,
 		RTE_EVENT_TYPE_CPU /* event_type */,
@@ -1238,7 +1240,7 @@ launch_multi_port_max_stages_random_sched_type(int (*fn)(void *))
 		return 0;
 	}
 
-	/* Injects events with m->seqn=0 to total_events */
+	/* Injects events with a 0 sequence number to total_events */
 	ret = inject_events(
 		0x1 /*flow_id */,
 		RTE_EVENT_TYPE_CPU /* event_type */,
@@ -1360,7 +1362,7 @@ worker_ordered_flow_producer(void *arg)
 		if (m == NULL)
 			continue;
 
-		m->seqn = counter++;
+		*rte_event_pmd_selftest_seqn(m) = counter++;
 
 		struct rte_event ev = {.event = 0, .u64 = 0};
 
diff --git a/drivers/event/octeontx2/otx2_evdev_selftest.c b/drivers/event/octeontx2/otx2_evdev_selftest.c
index 334a9ccb7c..48bfaf893d 100644
--- a/drivers/event/octeontx2/otx2_evdev_selftest.c
+++ b/drivers/event/octeontx2/otx2_evdev_selftest.c
@@ -279,7 +279,7 @@ inject_events(uint32_t flow_id, uint8_t event_type, uint8_t sub_event_type,
 		m = rte_pktmbuf_alloc(eventdev_test_mempool);
 		RTE_TEST_ASSERT_NOT_NULL(m, "mempool alloc failed");
 
-		m->seqn = i;
+		*rte_event_pmd_selftest_seqn(m) = i;
 		update_event_and_validation_attr(m, &ev, flow_id, event_type,
 						 sub_event_type, sched_type,
 						 queue, port);
@@ -301,7 +301,7 @@ check_excess_events(uint8_t port)
 
 		RTE_TEST_ASSERT_SUCCESS(valid_event,
 					"Unexpected valid event=%d",
-					ev.mbuf->seqn);
+					*rte_event_pmd_selftest_seqn(ev.mbuf));
 	}
 	return 0;
 }
@@ -406,8 +406,9 @@ static int
 validate_simple_enqdeq(uint32_t index, uint8_t port, struct rte_event *ev)
 {
 	RTE_SET_USED(port);
-	RTE_TEST_ASSERT_EQUAL(index, ev->mbuf->seqn, "index=%d != seqn=%d",
-			      index, ev->mbuf->seqn);
+	RTE_TEST_ASSERT_EQUAL(index, *rte_event_pmd_selftest_seqn(ev->mbuf),
+		"index=%d != seqn=%d",
+		index, *rte_event_pmd_selftest_seqn(ev->mbuf));
 	return 0;
 }
 
@@ -493,10 +494,11 @@ validate_queue_priority(uint32_t index, uint8_t port, struct rte_event *ev)
 
 	expected_val += ev->queue_id;
 	RTE_SET_USED(port);
-	RTE_TEST_ASSERT_EQUAL(ev->mbuf->seqn, expected_val,
-	"seqn=%d index=%d expected=%d range=%d nb_queues=%d max_event=%d",
-			      ev->mbuf->seqn, index, expected_val, range,
-			      queue_count, MAX_EVENTS);
+	RTE_TEST_ASSERT_EQUAL(
+		*rte_event_pmd_selftest_seqn(ev->mbuf), expected_val,
+		"seqn=%d index=%d expected=%d range=%d nb_queues=%d max_event=%d",
+		*rte_event_pmd_selftest_seqn(ev->mbuf), index, expected_val,
+		range, queue_count, MAX_EVENTS);
 	return 0;
 }
 
@@ -523,7 +525,7 @@ test_multi_queue_priority(void)
 		m = rte_pktmbuf_alloc(eventdev_test_mempool);
 		RTE_TEST_ASSERT_NOT_NULL(m, "mempool alloc failed");
 
-		m->seqn = i;
+		*rte_event_pmd_selftest_seqn(m) = i;
 		queue = i % queue_count;
 		update_event_and_validation_attr(m, &ev, 0, RTE_EVENT_TYPE_CPU,
 						 0, RTE_SCHED_TYPE_PARALLEL,
@@ -888,7 +890,9 @@ worker_flow_based_pipeline(void *arg)
 			ev.op = RTE_EVENT_OP_FORWARD;
 			rte_event_enqueue_burst(evdev, port, &ev, 1);
 		} else if (ev.sub_event_type == 1) { /* Events from stage 1*/
-			if (seqn_list_update(ev.mbuf->seqn) == 0) {
+			uint32_t seqn = *rte_event_pmd_selftest_seqn(ev.mbuf);
+
+			if (seqn_list_update(seqn) == 0) {
 				rte_pktmbuf_free(ev.mbuf);
 				rte_atomic32_sub(total_events, 1);
 			} else {
@@ -923,7 +927,7 @@ test_multiport_flow_sched_type_test(uint8_t in_sched_type,
 		return 0;
 	}
 
-	/* Injects events with m->seqn=0 to total_events */
+	/* Injects events with a 0 sequence number to total_events */
 	ret = inject_events(0x1 /*flow_id */,
 			    RTE_EVENT_TYPE_CPU /* event_type */,
 			    0 /* sub_event_type (stage 0) */,
@@ -1043,7 +1047,9 @@ worker_group_based_pipeline(void *arg)
 			ev.op = RTE_EVENT_OP_FORWARD;
 			rte_event_enqueue_burst(evdev, port, &ev, 1);
 		} else if (ev.queue_id == 1) { /* Events from stage 1(group 1)*/
-			if (seqn_list_update(ev.mbuf->seqn) == 0) {
+			uint32_t seqn = *rte_event_pmd_selftest_seqn(ev.mbuf);
+
+			if (seqn_list_update(seqn) == 0) {
 				rte_pktmbuf_free(ev.mbuf);
 				rte_atomic32_sub(total_events, 1);
 			} else {
@@ -1084,7 +1090,7 @@ test_multiport_queue_sched_type_test(uint8_t in_sched_type,
 		return 0;
 	}
 
-	/* Injects events with m->seqn=0 to total_events */
+	/* Injects events with a 0 sequence number to total_events */
 	ret = inject_events(0x1 /*flow_id */,
 			    RTE_EVENT_TYPE_CPU /* event_type */,
 			    0 /* sub_event_type (stage 0) */,
@@ -1222,7 +1228,7 @@ launch_multi_port_max_stages_random_sched_type(int (*fn)(void *))
 		return 0;
 	}
 
-	/* Injects events with m->seqn=0 to total_events */
+	/* Injects events with a 0 sequence number to total_events */
 	ret = inject_events(0x1 /*flow_id */,
 			    RTE_EVENT_TYPE_CPU /* event_type */,
 			    0 /* sub_event_type (stage 0) */,
@@ -1348,7 +1354,7 @@ worker_ordered_flow_producer(void *arg)
 		if (m == NULL)
 			continue;
 
-		m->seqn = counter++;
+		*rte_event_pmd_selftest_seqn(m) = counter++;
 
 		struct rte_event ev = {.event = 0, .u64 = 0};
 
diff --git a/drivers/event/opdl/opdl_test.c b/drivers/event/opdl/opdl_test.c
index e7a32fbd31..e4fc70a440 100644
--- a/drivers/event/opdl/opdl_test.c
+++ b/drivers/event/opdl/opdl_test.c
@@ -256,7 +256,7 @@ ordered_basic(struct test *t)
 		ev.queue_id = t->qid[0];
 		ev.op = RTE_EVENT_OP_NEW;
 		ev.mbuf = mbufs[i];
-		mbufs[i]->seqn = MAGIC_SEQN + i;
+		*rte_event_pmd_selftest_seqn(mbufs[i]) = MAGIC_SEQN + i;
 
 		/* generate pkt and enqueue */
 		err = rte_event_enqueue_burst(evdev, t->port[rx_port], &ev, 1);
@@ -281,7 +281,7 @@ ordered_basic(struct test *t)
 			rte_event_dev_dump(evdev, stdout);
 			return -1;
 		}
-		seq = deq_ev[i].mbuf->seqn  - MAGIC_SEQN;
+		seq = *rte_event_pmd_selftest_seqn(deq_ev[i].mbuf)  - MAGIC_SEQN;
 
 		if (seq != (i-1)) {
 			PMD_DRV_LOG(ERR, " seq test failed ! eq is %d , "
@@ -396,7 +396,7 @@ atomic_basic(struct test *t)
 		ev.op = RTE_EVENT_OP_NEW;
 		ev.flow_id = 1;
 		ev.mbuf = mbufs[i];
-		mbufs[i]->seqn = MAGIC_SEQN + i;
+		*rte_event_pmd_selftest_seqn(mbufs[i]) = MAGIC_SEQN + i;
 
 		/* generate pkt and enqueue */
 		err = rte_event_enqueue_burst(evdev, t->port[rx_port], &ev, 1);
@@ -625,7 +625,7 @@ single_link_w_stats(struct test *t)
 		ev.queue_id = t->qid[0];
 		ev.op = RTE_EVENT_OP_NEW;
 		ev.mbuf = mbufs[i];
-		mbufs[i]->seqn = 1234 + i;
+		*rte_event_pmd_selftest_seqn(mbufs[i]) = 1234 + i;
 
 		/* generate pkt and enqueue */
 		err = rte_event_enqueue_burst(evdev, t->port[rx_port], &ev, 1);
diff --git a/drivers/event/sw/sw_evdev_selftest.c b/drivers/event/sw/sw_evdev_selftest.c
index ad4fc0eed7..4555f799df 100644
--- a/drivers/event/sw/sw_evdev_selftest.c
+++ b/drivers/event/sw/sw_evdev_selftest.c
@@ -380,7 +380,7 @@ run_prio_packet_test(struct test *t)
 			printf("%d: gen of pkt failed\n", __LINE__);
 			return -1;
 		}
-		arp->seqn = MAGIC_SEQN[i];
+		*rte_event_pmd_selftest_seqn(arp) = MAGIC_SEQN[i];
 
 		ev = (struct rte_event){
 			.priority = PRIORITY[i],
@@ -419,7 +419,7 @@ run_prio_packet_test(struct test *t)
 		rte_event_dev_dump(evdev, stdout);
 		return -1;
 	}
-	if (ev.mbuf->seqn != MAGIC_SEQN[1]) {
+	if (*rte_event_pmd_selftest_seqn(ev.mbuf) != MAGIC_SEQN[1]) {
 		printf("%d: first packet out not highest priority\n",
 				__LINE__);
 		rte_event_dev_dump(evdev, stdout);
@@ -433,7 +433,7 @@ run_prio_packet_test(struct test *t)
 		rte_event_dev_dump(evdev, stdout);
 		return -1;
 	}
-	if (ev2.mbuf->seqn != MAGIC_SEQN[0]) {
+	if (*rte_event_pmd_selftest_seqn(ev2.mbuf) != MAGIC_SEQN[0]) {
 		printf("%d: second packet out not lower priority\n",
 				__LINE__);
 		rte_event_dev_dump(evdev, stdout);
@@ -477,7 +477,7 @@ test_single_directed_packet(struct test *t)
 	}
 
 	const uint32_t MAGIC_SEQN = 4711;
-	arp->seqn = MAGIC_SEQN;
+	*rte_event_pmd_selftest_seqn(arp) = MAGIC_SEQN;
 
 	/* generate pkt and enqueue */
 	err = rte_event_enqueue_burst(evdev, rx_enq, &ev, 1);
@@ -516,7 +516,7 @@ test_single_directed_packet(struct test *t)
 		return -1;
 	}
 
-	if (ev.mbuf->seqn != MAGIC_SEQN) {
+	if (*rte_event_pmd_selftest_seqn(ev.mbuf) != MAGIC_SEQN) {
 		printf("%d: error magic sequence number not dequeued\n",
 				__LINE__);
 		return -1;
@@ -934,7 +934,7 @@ xstats_tests(struct test *t)
 		ev.op = RTE_EVENT_OP_NEW;
 		ev.mbuf = arp;
 		ev.flow_id = 7;
-		arp->seqn = i;
+		*rte_event_pmd_selftest_seqn(arp) = i;
 
 		int err = rte_event_enqueue_burst(evdev, t->port[0], &ev, 1);
 		if (err != 1) {
@@ -1485,7 +1485,7 @@ xstats_id_reset_tests(struct test *t)
 		ev.queue_id = t->qid[i];
 		ev.op = RTE_EVENT_OP_NEW;
 		ev.mbuf = arp;
-		arp->seqn = i;
+		*rte_event_pmd_selftest_seqn(arp) = i;
 
 		int err = rte_event_enqueue_burst(evdev, t->port[0], &ev, 1);
 		if (err != 1) {
@@ -1873,7 +1873,7 @@ qid_priorities(struct test *t)
 		ev.queue_id = t->qid[i];
 		ev.op = RTE_EVENT_OP_NEW;
 		ev.mbuf = arp;
-		arp->seqn = i;
+		*rte_event_pmd_selftest_seqn(arp) = i;
 
 		int err = rte_event_enqueue_burst(evdev, t->port[0], &ev, 1);
 		if (err != 1) {
@@ -1894,7 +1894,7 @@ qid_priorities(struct test *t)
 		return -1;
 	}
 	for (i = 0; i < 3; i++) {
-		if (ev[i].mbuf->seqn != 2-i) {
+		if (*rte_event_pmd_selftest_seqn(ev[i].mbuf) != 2-i) {
 			printf(
 				"%d: qid priority test: seqn %d incorrectly prioritized\n",
 					__LINE__, i);
@@ -2371,7 +2371,7 @@ single_packet(struct test *t)
 	ev.mbuf = arp;
 	ev.queue_id = 0;
 	ev.flow_id = 3;
-	arp->seqn = MAGIC_SEQN;
+	*rte_event_pmd_selftest_seqn(arp) = MAGIC_SEQN;
 
 	err = rte_event_enqueue_burst(evdev, t->port[rx_enq], &ev, 1);
 	if (err != 1) {
@@ -2411,7 +2411,7 @@ single_packet(struct test *t)
 	}
 
 	err = test_event_dev_stats_get(evdev, &stats);
-	if (ev.mbuf->seqn != MAGIC_SEQN) {
+	if (*rte_event_pmd_selftest_seqn(ev.mbuf) != MAGIC_SEQN) {
 		printf("%d: magic sequence number not dequeued\n", __LINE__);
 		return -1;
 	}
@@ -2684,7 +2684,7 @@ parallel_basic(struct test *t, int check_order)
 		ev.queue_id = t->qid[0];
 		ev.op = RTE_EVENT_OP_NEW;
 		ev.mbuf = mbufs[i];
-		mbufs[i]->seqn = MAGIC_SEQN + i;
+		*rte_event_pmd_selftest_seqn(mbufs[i]) = MAGIC_SEQN + i;
 
 		/* generate pkt and enqueue */
 		err = rte_event_enqueue_burst(evdev, t->port[rx_port], &ev, 1);
@@ -2739,10 +2739,12 @@ parallel_basic(struct test *t, int check_order)
 	/* Check to see if the sequence numbers are in expected order */
 	if (check_order) {
 		for (j = 0 ; j < deq_pkts ; j++) {
-			if (deq_ev[j].mbuf->seqn != MAGIC_SEQN + j) {
-				printf(
-					"%d: Incorrect sequence number(%d) from port %d\n",
-					__LINE__, mbufs_out[j]->seqn, tx_port);
+			if (*rte_event_pmd_selftest_seqn(deq_ev[j].mbuf) !=
+					MAGIC_SEQN + j) {
+				printf("%d: Incorrect sequence number(%d) from port %d\n",
+					__LINE__,
+					*rte_event_pmd_selftest_seqn(mbufs_out[j]),
+					tx_port);
 				return -1;
 			}
 		}
diff --git a/lib/librte_eventdev/rte_eventdev.c b/lib/librte_eventdev/rte_eventdev.c
index 322453c532..994bd1eaa9 100644
--- a/lib/librte_eventdev/rte_eventdev.c
+++ b/lib/librte_eventdev/rte_eventdev.c
@@ -1242,13 +1242,25 @@ int rte_event_dev_xstats_reset(uint8_t dev_id,
 	return -ENOTSUP;
 }
 
+int rte_event_pmd_selftest_seqn_dynfield_offset = -1;
+
 int rte_event_dev_selftest(uint8_t dev_id)
 {
 	RTE_EVENTDEV_VALID_DEVID_OR_ERR_RET(dev_id, -EINVAL);
+	static const struct rte_mbuf_dynfield test_seqn_dynfield_desc = {
+		.name = "rte_event_pmd_selftest_seqn_dynfield",
+		.size = sizeof(rte_event_pmd_selftest_seqn_t),
+		.align = __alignof__(rte_event_pmd_selftest_seqn_t),
+	};
 	struct rte_eventdev *dev = &rte_eventdevs[dev_id];
 
-	if (dev->dev_ops->dev_selftest != NULL)
+	if (dev->dev_ops->dev_selftest != NULL) {
+		rte_event_pmd_selftest_seqn_dynfield_offset =
+			rte_mbuf_dynfield_register(&test_seqn_dynfield_desc);
+		if (rte_event_pmd_selftest_seqn_dynfield_offset < 0)
+			return -ENOMEM;
 		return (*dev->dev_ops->dev_selftest)();
+	}
 	return -ENOTSUP;
 }
 
diff --git a/lib/librte_eventdev/rte_eventdev_pmd.h b/lib/librte_eventdev/rte_eventdev_pmd.h
index d118b9e5ba..27be376ed1 100644
--- a/lib/librte_eventdev/rte_eventdev_pmd.h
+++ b/lib/librte_eventdev/rte_eventdev_pmd.h
@@ -20,10 +20,13 @@ extern "C" {
 #include <string.h>
 
 #include <rte_common.h>
+#include <rte_compat.h>
 #include <rte_config.h>
 #include <rte_dev.h>
 #include <rte_log.h>
 #include <rte_malloc.h>
+#include <rte_mbuf.h>
+#include <rte_mbuf_dyn.h>
 
 #include "rte_eventdev.h"
 #include "rte_event_timer_adapter_pmd.h"
@@ -635,6 +638,23 @@ typedef int (*eventdev_eth_rx_adapter_stats_reset)
  */
 typedef int (*eventdev_selftest)(void);
 
+typedef uint32_t rte_event_pmd_selftest_seqn_t;
+extern int rte_event_pmd_selftest_seqn_dynfield_offset;
+
+/**
+ * Read test sequence number from mbuf.
+ *
+ * @param mbuf Structure to read from.
+ * @return pointer to test sequence number.
+ */
+__rte_internal
+static inline rte_event_pmd_selftest_seqn_t *
+rte_event_pmd_selftest_seqn(struct rte_mbuf *mbuf)
+{
+	return RTE_MBUF_DYNFIELD(mbuf,
+		rte_event_pmd_selftest_seqn_dynfield_offset,
+		rte_event_pmd_selftest_seqn_t *);
+}
 
 struct rte_cryptodev;
 
diff --git a/lib/librte_eventdev/version.map b/lib/librte_eventdev/version.map
index 8ae8420f9b..3e5c09cfdb 100644
--- a/lib/librte_eventdev/version.map
+++ b/lib/librte_eventdev/version.map
@@ -139,3 +139,9 @@ EXPERIMENTAL {
 	# added in 20.11
 	rte_event_pmd_pci_probe_named;
 };
+
+INTERNAL {
+	global:
+
+	rte_event_pmd_selftest_seqn_dynfield_offset;
+};
