[dpdk-dev] [PATCH v2] net/failsafe: fix VLAN stripping configuration

[Ophir Munk]

failsafe device has vlan stripping configured at startup however once
a sub device is found as non-capable of vlan-stripping failsafe
updates it configuration and removes vlan stripping from it.
This update occurs only once at startup. Following a later plugin
attempt and in case of vlan stripping mismatch between failsafe
configuration and device capability - failsafe cannot recover and the
device remains constantly in plug out state.

The sequence of events leading to this situation is described as
follows:
1. Start testpmd with failsafe where mlx4 is a sub device (not capable
of vlan stripping). Expected printout:
PMD: net_failsafe: Disabling VLAN stripping offload
2. Execute:
testpmd> port stop all
testpmd> port config all max-pkt-len 2048
testpmd> port start all
3. Do a plug out (e.g. disable sriov)
4. Do a plug in (e.g. enable sriov)
5. Expected result: failsafe successfully configures and starts its sub
devices
Actual result: failsafe is continuously failing with these messages:
PMD: net_failsafe: VLAN stripping offload requested but not supported by
sub_device 0
PMD: net_failsafe: device already configured, cannot fix live
configuration
PMD: net_failsafe: Unable to synchronize sub device state

Root cause analysis: at startup failsafe removes vlan stripping from its
configuration. After executing "port config all max-pkt-len 2048"
testpmd marks failsafe in need for configuration update.
After executing "port start all" testpmd overrides failsafe
configuration with its own configuration which includes vlan stripping

During the plugin attempt failsafe refuses to update its configuration
by removing vlan stripping since it has already updated its
configuration at startup.

The fix is for failsafe to stop validation and disabling non-supported
offloads in its sub-devices.

Cc: stable at dpdk.org
Fixes: bbc6a53dda44 ("net/failsafe: support Rx offload capabilities")

Signed-off-by: Ophir Munk <ophirmu at mellanox.com>
---
 drivers/net/failsafe/failsafe_ops.c | 118 ------------------------------------
 1 file changed, 118 deletions(-)

diff --git a/drivers/net/failsafe/failsafe_ops.c b/drivers/net/failsafe/failsafe_ops.c
index f460551..e16a590 100644
--- a/drivers/net/failsafe/failsafe_ops.c
+++ b/drivers/net/failsafe/failsafe_ops.c
@@ -80,132 +80,14 @@
 	.flow_type_rss_offloads = 0x0,
 };
 
-/**
- * Check whether a specific offloading capability
- * is supported by a sub_device.
- *
- * @return
- *   0: all requested capabilities are supported by the sub_device
- *   positive value: This flag at least is not supported by the sub_device
- */
-static int
-fs_port_offload_validate(struct rte_eth_dev *dev,
-			 struct sub_device *sdev)
-{
-	struct rte_eth_dev_info infos = {0};
-	struct rte_eth_conf *cf;
-	uint32_t cap;
-
-	cf = &dev->data->dev_conf;
-	SUBOPS(sdev, dev_infos_get)(ETH(sdev), &infos);
-	/* RX capabilities */
-	cap = infos.rx_offload_capa;
-	if (cf->rxmode.hw_vlan_strip &&
-	    ((cap & DEV_RX_OFFLOAD_VLAN_STRIP) == 0)) {
-		WARN("VLAN stripping offload requested but not supported by sub_device %d",
-		      SUB_ID(sdev));
-		return DEV_RX_OFFLOAD_VLAN_STRIP;
-	}
-	if (cf->rxmode.hw_ip_checksum &&
-	    ((cap & (DEV_RX_OFFLOAD_IPV4_CKSUM |
-		     DEV_RX_OFFLOAD_UDP_CKSUM |
-		     DEV_RX_OFFLOAD_TCP_CKSUM)) !=
-	     (DEV_RX_OFFLOAD_IPV4_CKSUM |
-	      DEV_RX_OFFLOAD_UDP_CKSUM |
-	      DEV_RX_OFFLOAD_TCP_CKSUM))) {
-		WARN("IP checksum offload requested but not supported by sub_device %d",
-		      SUB_ID(sdev));
-		return DEV_RX_OFFLOAD_IPV4_CKSUM |
-		       DEV_RX_OFFLOAD_UDP_CKSUM |
-		       DEV_RX_OFFLOAD_TCP_CKSUM;
-	}
-	if (cf->rxmode.enable_lro &&
-	    ((cap & DEV_RX_OFFLOAD_TCP_LRO) == 0)) {
-		WARN("TCP LRO offload requested but not supported by sub_device %d",
-		      SUB_ID(sdev));
-		return DEV_RX_OFFLOAD_TCP_LRO;
-	}
-	if (cf->rxmode.hw_vlan_extend &&
-	    ((cap & DEV_RX_OFFLOAD_QINQ_STRIP) == 0)) {
-		WARN("Stacked VLAN stripping offload requested but not supported by sub_device %d",
-		      SUB_ID(sdev));
-		return DEV_RX_OFFLOAD_QINQ_STRIP;
-	}
-	/* TX capabilities */
-	/* Nothing to do, no tx capa supported */
-	return 0;
-}
-
-/*
- * Disable the dev_conf flag related to an offload capability flag
- * within an ethdev configuration.
- */
-static int
-fs_port_disable_offload(struct rte_eth_conf *cf,
-			uint32_t ol_cap)
-{
-	switch (ol_cap) {
-	case DEV_RX_OFFLOAD_VLAN_STRIP:
-		INFO("Disabling VLAN stripping offload");
-		cf->rxmode.hw_vlan_strip = 0;
-		break;
-	case DEV_RX_OFFLOAD_IPV4_CKSUM:
-	case DEV_RX_OFFLOAD_UDP_CKSUM:
-	case DEV_RX_OFFLOAD_TCP_CKSUM:
-	case (DEV_RX_OFFLOAD_IPV4_CKSUM |
-	      DEV_RX_OFFLOAD_UDP_CKSUM |
-	      DEV_RX_OFFLOAD_TCP_CKSUM):
-		INFO("Disabling IP checksum offload");
-		cf->rxmode.hw_ip_checksum = 0;
-		break;
-	case DEV_RX_OFFLOAD_TCP_LRO:
-		INFO("Disabling TCP LRO offload");
-		cf->rxmode.enable_lro = 0;
-		break;
-	case DEV_RX_OFFLOAD_QINQ_STRIP:
-		INFO("Disabling stacked VLAN stripping offload");
-		cf->rxmode.hw_vlan_extend = 0;
-		break;
-	default:
-		DEBUG("Unable to disable offload capability: %" PRIx32,
-		      ol_cap);
-		return -1;
-	}
-	return 0;
-}
-
 static int
 fs_dev_configure(struct rte_eth_dev *dev)
 {
 	struct sub_device *sdev;
 	uint8_t i;
-	int capa_flag;
 	int ret;
 
 	FOREACH_SUBDEV(sdev, i, dev) {
-		if (sdev->state != DEV_PROBED)
-			continue;
-		DEBUG("Checking capabilities for sub_device %d", i);
-		while ((capa_flag = fs_port_offload_validate(dev, sdev))) {
-			/*
-			 * Refuse to change configuration if multiple devices
-			 * are present and we already have configured at least
-			 * some of them.
-			 */
-			if (PRIV(dev)->state >= DEV_ACTIVE &&
-			    PRIV(dev)->subs_tail > 1) {
-				ERROR("device already configured, cannot fix live configuration");
-				return -1;
-			}
-			ret = fs_port_disable_offload(&dev->data->dev_conf,
-						      capa_flag);
-			if (ret) {
-				ERROR("Unable to disable offload capability");
-				return ret;
-			}
-		}
-	}
-	FOREACH_SUBDEV(sdev, i, dev) {
 		int rmv_interrupt = 0;
 		int lsc_interrupt = 0;
 		int lsc_enabled;
-- 
1.8.3.1