fix ethdev port id validation

Some DPDK applications wrongly assume these requirements:
    - no hotplug, i.e. ports are never detached
    - all allocated ports are available to the application

Such application assume a valid port index is in the range [0..count[.

There are three consequences when using such wrong design:
    - new ports having an index higher than the port count won't be valid
    - old ports being detached (RTE_ETH_DEV_UNUSED) can be valid

Such mistake will be less common with growing hotplug awareness.
All applications and examples inside this repository - except testpmd -
must be fixed to use the function rte_eth_dev_is_valid_port.

Signed-off-by: Thomas Monjalon <thomas@monjalon.net>

1 files changed, 4 insertions, 4 deletions

diff --git a/examples/vmdq_dcb/main.c b/examples/vmdq_dcb/main.c
index 2016a95716..9c68ab0895 100644
--- a/examples/vmdq_dcb/main.c
+++ b/examples/vmdq_dcb/main.c
@@ -246,7 +246,7 @@ port_init(uint16_t port, struct rte_mempool *mbuf_pool)
 			num_pools, queues_per_pool);
 	}
 
-	if (port >= rte_eth_dev_count())
+	if (!rte_eth_dev_is_valid_port(port))
 		return -1;
 
 	retval = get_eth_conf(&port_conf);
@@ -599,9 +599,9 @@ static unsigned check_ports_num(unsigned nb_ports)
 	}
 
 	for (portid = 0; portid < num_ports; portid++) {
-		if (ports[portid] >= nb_ports) {
-			printf("\nSpecified port ID(%u) exceeds max system port ID(%u)\n",
-				ports[portid], (nb_ports - 1));
+		if (!rte_eth_dev_is_valid_port(ports[portid])) {
+			printf("\nSpecified port ID(%u) is not valid\n",
+				ports[portid]);
 			ports[portid] = INVALID_PORT_ID;
 			valid_num_ports--;
 		}