[dpdk-stable] [17.11] examples/bond: fix crash when there is no active slave

[Radu Nicolau]

[ backported from upstream commit 292fdb76024f ]

If bond_ethdev_rx_burst() called more times with no active slaves
the active slave index will point out of bounds, resulting in a
segfault.
The configured slaves needs to be checked, and if none became active
there is no point going further.

Do not start the packet processing threads until all configured
slaves become active.

Fixes: cc7e8ae84faa ("examples/bond: add example application for link bonding mode 6")

Signed-off-by: Radu Nicolau <radu.nicolau at intel.com>
Acked-by: Chas Williams <chas3 at att.com>
---
 examples/bond/main.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/examples/bond/main.c b/examples/bond/main.c
index 4f533e2..317e217 100644
--- a/examples/bond/main.c
+++ b/examples/bond/main.c
@@ -225,6 +225,7 @@ bond_port_init(struct rte_mempool *mbuf_pool)
 	uint8_t i;
 	uint16_t nb_rxd = RTE_RX_DESC_DEFAULT;
 	uint16_t nb_txd = RTE_TX_DESC_DEFAULT;
+	uint16_t wait_counter = 20;
 
 	retval = rte_eth_bond_create("net_bonding0", BONDING_MODE_ALB,
 			0 /*SOCKET_ID_ANY*/);
@@ -271,6 +272,21 @@ bond_port_init(struct rte_mempool *mbuf_pool)
 	if (retval < 0)
 		rte_exit(retval, "Start port %d failed (res=%d)", BOND_PORT, retval);
 
+	printf("Waiting for slaves to become active...");
+	while (wait_counter) {
+		uint16_t act_slaves[16] = {0};
+		if (rte_eth_bond_active_slaves_get(BOND_PORT, act_slaves, 16) ==
+				slaves_count) {
+			printf("\n");
+			break;
+		}
+		sleep(1);
+		printf("...");
+		if (--wait_counter == 0)
+			rte_exit(-1, "\nFailed to activate slaves\n");
+	}
+
+
 	rte_eth_promiscuous_enable(BOND_PORT);
 
 	struct ether_addr addr;
-- 
2.7.5