[PATCH] net/iavf: ensure no polling during VF initiated reset

[Ciara Loftus <ciara.loftus@intel.com>]

Ensure that the datapath functions will not poll during a vf initiated
reset. Otherwise the datapath could access freed resources and cause a
core dump. Achieve this by ensuring that the no-poll-on-link-down devarg
is set when trying to reinit a started device. If it's not set, suggest
stopping the port before the reinit.

Signed-off-by: Ciara Loftus <ciara.loftus@intel.com>
---
 drivers/net/intel/iavf/iavf_ethdev.c | 40 +++++++++++++++++++++-------
 1 file changed, 30 insertions(+), 10 deletions(-)

diff --git a/drivers/net/intel/iavf/iavf_ethdev.c b/drivers/net/intel/iavf/iavf_ethdev.c
index 95e5832f03..72d79447e1 100644
--- a/drivers/net/intel/iavf/iavf_ethdev.c
+++ b/drivers/net/intel/iavf/iavf_ethdev.c
@@ -3102,13 +3102,18 @@ iavf_handle_hw_reset(struct rte_eth_dev *dev, bool vf_initiated_reset)
 	struct iavf_info *vf = IAVF_DEV_PRIVATE_TO_VF(dev->data->dev_private);
 	struct iavf_adapter *adapter = dev->data->dev_private;
 	int ret;
+	bool restart_device = false;
 
-	if (!dev->data->dev_started)
-		return;
+	if (vf_initiated_reset) {
+		restart_device = dev->data->dev_started;
+	} else {
+		if (!dev->data->dev_started)
+			return;
 
-	if (!vf_initiated_reset && !iavf_is_reset_detected(adapter)) {
-		PMD_DRV_LOG(DEBUG, "reset not start");
-		return;
+		if (!iavf_is_reset_detected(adapter)) {
+			PMD_DRV_LOG(DEBUG, "reset not start");
+			return;
+		}
 	}
 
 	vf->in_reset_recovery = true;
@@ -3125,12 +3130,14 @@ iavf_handle_hw_reset(struct rte_eth_dev *dev, bool vf_initiated_reset)
 
 	iavf_dev_xstats_reset(dev);
 
-	/* start the device */
-	ret = iavf_dev_start(dev);
-	if (ret)
-		goto error;
+	if (!vf_initiated_reset || restart_device) {
+		/* start the device */
+		ret = iavf_dev_start(dev);
+		if (ret)
+			goto error;
 
-	dev->data->dev_started = 1;
+		dev->data->dev_started = 1;
+	}
 	goto exit;
 
 error:
@@ -3147,6 +3154,7 @@ int
 rte_pmd_iavf_reinit(uint16_t port)
 {
 	struct rte_eth_dev *dev;
+	struct iavf_adapter *adapter;
 
 	RTE_ETH_VALID_PORTID_OR_ERR_RET(port, -ENODEV);
 
@@ -3157,6 +3165,18 @@ rte_pmd_iavf_reinit(uint16_t port)
 		return -ENOTSUP;
 	}
 
+	if (!dev->data->dev_configured) {
+		PMD_DRV_LOG(ERR, "Cannot reinit unconfigured port %u.", port);
+		return -EINVAL;
+	}
+
+	adapter = dev->data->dev_private;
+	if (dev->data->dev_started && !adapter->devargs.no_poll_on_link_down) {
+		PMD_DRV_LOG(ERR, "Cannot reinit started port %u. Either stop the port or enable "
+				"no-poll-on-link-down in devargs.", port);
+		return -EINVAL;
+	}
+
 	iavf_handle_hw_reset(dev, true);
 
 	return 0;
-- 
2.34.1