[dpdk-dev] [PATCH] net/vdev_netvsc: print warning if Mellanox devices are not configured

[Stephen Hemminger <stephen@networkplumber.org>]

Several users have run into problems where the MLX drivers were not
enabled in their build. And then trying to run their DPDK
application on Azure. What happens is that all packets
go over the slow path, and failsafe repeatedly probes for never
existing sub-device.

Both Mellanox drivers should be checked. MLX4 for current versions,
and MLX5 for future upgrades. This code is only called if Hyper-V/Azure
is detected.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
---
 drivers/net/vdev_netvsc/vdev_netvsc.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/net/vdev_netvsc/vdev_netvsc.c b/drivers/net/vdev_netvsc/vdev_netvsc.c
index 801f54c96e01..64f9dbf66e18 100644
--- a/drivers/net/vdev_netvsc/vdev_netvsc.c
+++ b/drivers/net/vdev_netvsc/vdev_netvsc.c
@@ -812,6 +812,13 @@ vdev_netvsc_scan_callback(__rte_unused void *arg)
 	struct rte_devargs *devargs;
 	struct rte_bus *vbus = rte_bus_find_by_name("vdev");
 
+#ifndef RTE_LIBRTE_MLX4_PMD
+	DRV_LOG(WARNING, "Mellanox MLX4 not configured.");
+#endif
+#ifndef RTE_LIBRTE_MLX5_PMD
+	DRV_LOG(WARNING, "Mellanox MLX5 not configured.");
+#endif
+
 	RTE_EAL_DEVARGS_FOREACH("vdev", devargs)
 		if (!strncmp(devargs->name, VDEV_NETVSC_DRIVER_NAME,
 			     VDEV_NETVSC_DRIVER_NAME_LEN))
-- 
2.20.1