[dpdk-stable] [PATCH] net/mlx4: fix probe failure report

[Matan Azrad]

[ backported from upstream commit
8d0f80167d43949bd24374bcf294a149246dfd1c ]

The corrupted code doesn't return error when probe function
fails due to error in device mac address getting.
By this way, the probe function may return success even if the
ETH dev is not allocated.

Hence, the probe caller, for example failsafe PMD, fails when it
tries to get ETH dev after the device was plugged out while mlx4
was probing it.

The fix adds error report to the probe caller when priv_get_mac fails
and in all other failure options which are missing it.

By this way, it prevents the unexpected behavior to miss ETH device
after the device was probed successfully.

Fixes: 7fae69eeff13 ("mlx4: new poll mode driver")
Fixes: 7b0661539229 ("mlx4: check if port is configured for ethernet")
Fixes: fec3608673e6 ("mlx4: query netdevice to get initial MAC address")
Cc: stable at dpdk.org

Signed-off-by: Matan Azrad <matan at mellanox.com>
Acked-by: Adrien Mazarguil <adrien.mazarguil at 6wind.com>
---
 drivers/net/mlx4/mlx4.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/net/mlx4/mlx4.c b/drivers/net/mlx4/mlx4.c
index f682413..4a03d34 100644
--- a/drivers/net/mlx4/mlx4.c
+++ b/drivers/net/mlx4/mlx4.c
@@ -5625,8 +5625,10 @@ mlx4_pci_probe(struct rte_pci_driver *pci_drv, struct rte_pci_device *pci_dev)
 	ibv_dev = list[i];
 
 	DEBUG("device opened");
-	if (ibv_query_device(attr_ctx, &device_attr))
+	if (ibv_query_device(attr_ctx, &device_attr)) {
+		err = EINVAL;
 		goto error;
+	}
 	INFO("%u port(s) detected", device_attr.phys_port_cnt);
 
 	for (i = 0; i < device_attr.phys_port_cnt; i++) {
@@ -5652,19 +5654,23 @@ mlx4_pci_probe(struct rte_pci_driver *pci_drv, struct rte_pci_device *pci_dev)
 		DEBUG("using port %u (%08" PRIx32 ")", port, test);
 
 		ctx = ibv_open_device(ibv_dev);
-		if (ctx == NULL)
+		if (ctx == NULL) {
+			err = ENODEV;
 			goto port_error;
+		}
 
 		/* Check port status. */
 		err = ibv_query_port(ctx, port, &port_attr);
 		if (err) {
 			ERROR("port query failed: %s", strerror(err));
+			err = ENODEV;
 			goto port_error;
 		}
 
 		if (port_attr.link_layer != IBV_LINK_LAYER_ETHERNET) {
 			ERROR("port %d is not configured in Ethernet mode",
 			      port);
+			err = EINVAL;
 			goto port_error;
 		}
 
@@ -5701,6 +5707,7 @@ mlx4_pci_probe(struct rte_pci_driver *pci_drv, struct rte_pci_device *pci_dev)
 #ifdef HAVE_EXP_QUERY_DEVICE
 		if (ibv_exp_query_device(ctx, &exp_device_attr)) {
 			ERROR("ibv_exp_query_device() failed");
+			err = ENODEV;
 			goto port_error;
 		}
 #ifdef RSS_SUPPORT
@@ -5776,6 +5783,7 @@ mlx4_pci_probe(struct rte_pci_driver *pci_drv, struct rte_pci_device *pci_dev)
 		if (priv_get_mac(priv, &mac.addr_bytes)) {
 			ERROR("cannot get MAC address, is mlx4_en loaded?"
 			      " (errno: %s)", strerror(errno));
+			err = ENODEV;
 			goto port_error;
 		}
 		INFO("port %u MAC address is %02x:%02x:%02x:%02x:%02x:%02x",
-- 
2.7.4