Merge branch '40GbE' of git://git.kernel.org/pub/scm/linux/kernel/git/tnguy/net-queue

Tony Nguyen says:

====================
Intel Wired LAN Driver Updates 2022-02-25

This series contains updates to iavf driver only.

Slawomir fixes stability issues that can be seen when stressing the
driver using a large number of VFs with a multitude of operations.
Among the fixes are reworking mutexes to provide more effective locking,
ensuring initialization is complete before teardown, preventing
operations which could race while removing the driver, stopping certain
tasks from being queued when the device is down, and adding a missing
mutex unlock.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 114 insertions, 75 deletions

diff --git a/drivers/net/ethernet/intel/iavf/iavf.h b/drivers/net/ethernet/intel/iavf/iavf.h
index 59806d1f7e79..89423947ee65 100644
--- a/drivers/net/ethernet/intel/iavf/iavf.h
+++ b/drivers/net/ethernet/intel/iavf/iavf.h
@@ -201,6 +201,10 @@ enum iavf_state_t {
 	__IAVF_RUNNING,		/* opened, working */
 };
 
+enum iavf_critical_section_t {
+	__IAVF_IN_REMOVE_TASK,	/* device being removed */
+};
+
 #define IAVF_CLOUD_FIELD_OMAC		0x01
 #define IAVF_CLOUD_FIELD_IMAC		0x02
 #define IAVF_CLOUD_FIELD_IVLAN	0x04
@@ -246,7 +250,6 @@ struct iavf_adapter {
 	struct list_head mac_filter_list;
 	struct mutex crit_lock;
 	struct mutex client_lock;
-	struct mutex remove_lock;
 	/* Lock to protect accesses to MAC and VLAN lists */
 	spinlock_t mac_vlan_list_lock;
 	char misc_vector_name[IFNAMSIZ + 9];
@@ -284,6 +287,7 @@ struct iavf_adapter {
 #define IAVF_FLAG_LEGACY_RX			BIT(15)
 #define IAVF_FLAG_REINIT_ITR_NEEDED		BIT(16)
 #define IAVF_FLAG_QUEUES_DISABLED		BIT(17)
+#define IAVF_FLAG_SETUP_NETDEV_FEATURES		BIT(18)
 /* duplicates for common code */
 #define IAVF_FLAG_DCB_ENABLED			0
 	/* flags for admin queue service task */
diff --git a/drivers/net/ethernet/intel/iavf/iavf_main.c b/drivers/net/ethernet/intel/iavf/iavf_main.c
index 8125b9120615..dcf24264c7ea 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_main.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_main.c
@@ -302,8 +302,9 @@ static irqreturn_t iavf_msix_aq(int irq, void *data)
 	rd32(hw, IAVF_VFINT_ICR01);
 	rd32(hw, IAVF_VFINT_ICR0_ENA1);
 
-	/* schedule work on the private workqueue */
-	queue_work(iavf_wq, &adapter->adminq_task);
+	if (adapter->state != __IAVF_REMOVE)
+		/* schedule work on the private workqueue */
+		queue_work(iavf_wq, &adapter->adminq_task);
 
 	return IRQ_HANDLED;
 }
@@ -1136,8 +1137,7 @@ void iavf_down(struct iavf_adapter *adapter)
 		rss->state = IAVF_ADV_RSS_DEL_REQUEST;
 	spin_unlock_bh(&adapter->adv_rss_lock);
 
-	if (!(adapter->flags & IAVF_FLAG_PF_COMMS_FAILED) &&
-	    adapter->state != __IAVF_RESETTING) {
+	if (!(adapter->flags & IAVF_FLAG_PF_COMMS_FAILED)) {
 		/* cancel any current operation */
 		adapter->current_op = VIRTCHNL_OP_UNKNOWN;
 		/* Schedule operations to close down the HW. Don't wait
@@ -2374,17 +2374,22 @@ static void iavf_watchdog_task(struct work_struct *work)
 	struct iavf_hw *hw = &adapter->hw;
 	u32 reg_val;
 
-	if (!mutex_trylock(&adapter->crit_lock))
+	if (!mutex_trylock(&adapter->crit_lock)) {
+		if (adapter->state == __IAVF_REMOVE)
+			return;
+
 		goto restart_watchdog;
+	}
 
 	if (adapter->flags & IAVF_FLAG_PF_COMMS_FAILED)
 		iavf_change_state(adapter, __IAVF_COMM_FAILED);
 
-	if (adapter->flags & IAVF_FLAG_RESET_NEEDED &&
-	    adapter->state != __IAVF_RESETTING) {
-		iavf_change_state(adapter, __IAVF_RESETTING);
+	if (adapter->flags & IAVF_FLAG_RESET_NEEDED) {
 		adapter->aq_required = 0;
 		adapter->current_op = VIRTCHNL_OP_UNKNOWN;
+		mutex_unlock(&adapter->crit_lock);
+		queue_work(iavf_wq, &adapter->reset_task);
+		return;
 	}
 
 	switch (adapter->state) {
@@ -2419,6 +2424,15 @@ static void iavf_watchdog_task(struct work_struct *work)
 				   msecs_to_jiffies(1));
 		return;
 	case __IAVF_INIT_FAILED:
+		if (test_bit(__IAVF_IN_REMOVE_TASK,
+			     &adapter->crit_section)) {
+			/* Do not update the state and do not reschedule
+			 * watchdog task, iavf_remove should handle this state
+			 * as it can loop forever
+			 */
+			mutex_unlock(&adapter->crit_lock);
+			return;
+		}
 		if (++adapter->aq_wait_count > IAVF_AQ_MAX_ERR) {
 			dev_err(&adapter->pdev->dev,
 				"Failed to communicate with PF; waiting before retry\n");
@@ -2435,6 +2449,17 @@ static void iavf_watchdog_task(struct work_struct *work)
 		queue_delayed_work(iavf_wq, &adapter->watchdog_task, HZ);
 		return;
 	case __IAVF_COMM_FAILED:
+		if (test_bit(__IAVF_IN_REMOVE_TASK,
+			     &adapter->crit_section)) {
+			/* Set state to __IAVF_INIT_FAILED and perform remove
+			 * steps. Remove IAVF_FLAG_PF_COMMS_FAILED so the task
+			 * doesn't bring the state back to __IAVF_COMM_FAILED.
+			 */
+			iavf_change_state(adapter, __IAVF_INIT_FAILED);
+			adapter->flags &= ~IAVF_FLAG_PF_COMMS_FAILED;
+			mutex_unlock(&adapter->crit_lock);
+			return;
+		}
 		reg_val = rd32(hw, IAVF_VFGEN_RSTAT) &
 			  IAVF_VFGEN_RSTAT_VFR_STATE_MASK;
 		if (reg_val == VIRTCHNL_VFR_VFACTIVE ||
@@ -2507,7 +2532,8 @@ static void iavf_watchdog_task(struct work_struct *work)
 	schedule_delayed_work(&adapter->client_task, msecs_to_jiffies(5));
 	mutex_unlock(&adapter->crit_lock);
 restart_watchdog:
-	queue_work(iavf_wq, &adapter->adminq_task);
+	if (adapter->state >= __IAVF_DOWN)
+		queue_work(iavf_wq, &adapter->adminq_task);
 	if (adapter->aq_required)
 		queue_delayed_work(iavf_wq, &adapter->watchdog_task,
 				   msecs_to_jiffies(20));
@@ -2601,13 +2627,13 @@ static void iavf_reset_task(struct work_struct *work)
 	/* When device is being removed it doesn't make sense to run the reset
 	 * task, just return in such a case.
 	 */
-	if (mutex_is_locked(&adapter->remove_lock))
-		return;
+	if (!mutex_trylock(&adapter->crit_lock)) {
+		if (adapter->state != __IAVF_REMOVE)
+			queue_work(iavf_wq, &adapter->reset_task);
 
-	if (iavf_lock_timeout(&adapter->crit_lock, 200)) {
-		schedule_work(&adapter->reset_task);
 		return;
 	}
+
 	while (!mutex_trylock(&adapter->client_lock))
 		usleep_range(500, 1000);
 	if (CLIENT_ENABLED(adapter)) {
@@ -2662,6 +2688,7 @@ static void iavf_reset_task(struct work_struct *work)
 			reg_val);
 		iavf_disable_vf(adapter);
 		mutex_unlock(&adapter->client_lock);
+		mutex_unlock(&adapter->crit_lock);
 		return; /* Do not attempt to reinit. It's dead, Jim. */
 	}
 
@@ -2670,8 +2697,7 @@ continue_reset:
 	 * ndo_open() returning, so we can't assume it means all our open
 	 * tasks have finished, since we're not holding the rtnl_lock here.
 	 */
-	running = ((adapter->state == __IAVF_RUNNING) ||
-		   (adapter->state == __IAVF_RESETTING));
+	running = adapter->state == __IAVF_RUNNING;
 
 	if (running) {
 		netdev->flags &= ~IFF_UP;
@@ -2826,13 +2852,19 @@ static void iavf_adminq_task(struct work_struct *work)
 	if (adapter->flags & IAVF_FLAG_PF_COMMS_FAILED)
 		goto out;
 
+	if (!mutex_trylock(&adapter->crit_lock)) {
+		if (adapter->state == __IAVF_REMOVE)
+			return;
+
+		queue_work(iavf_wq, &adapter->adminq_task);
+		goto out;
+	}
+
 	event.buf_len = IAVF_MAX_AQ_BUF_SIZE;
 	event.msg_buf = kzalloc(event.buf_len, GFP_KERNEL);
 	if (!event.msg_buf)
 		goto out;
 
-	if (iavf_lock_timeout(&adapter->crit_lock, 200))
-		goto freedom;
 	do {
 		ret = iavf_clean_arq_element(hw, &event, &pending);
 		v_op = (enum virtchnl_ops)le32_to_cpu(event.desc.cookie_high);
@@ -2848,6 +2880,24 @@ static void iavf_adminq_task(struct work_struct *work)
 	} while (pending);
 	mutex_unlock(&adapter->crit_lock);
 
+	if ((adapter->flags & IAVF_FLAG_SETUP_NETDEV_FEATURES)) {
+		if (adapter->netdev_registered ||
+		    !test_bit(__IAVF_IN_REMOVE_TASK, &adapter->crit_section)) {
+			struct net_device *netdev = adapter->netdev;
+
+			rtnl_lock();
+			netdev_update_features(netdev);
+			rtnl_unlock();
+			/* Request VLAN offload settings */
+			if (VLAN_V2_ALLOWED(adapter))
+				iavf_set_vlan_offload_features
+					(adapter, 0, netdev->features);
+
+			iavf_set_queue_vlan_tag_loc(adapter);
+		}
+
+		adapter->flags &= ~IAVF_FLAG_SETUP_NETDEV_FEATURES;
+	}
 	if ((adapter->flags &
 	     (IAVF_FLAG_RESET_PENDING | IAVF_FLAG_RESET_NEEDED)) ||
 	    adapter->state == __IAVF_RESETTING)
@@ -3800,11 +3850,12 @@ static int iavf_close(struct net_device *netdev)
 	struct iavf_adapter *adapter = netdev_priv(netdev);
 	int status;
 
-	if (adapter->state <= __IAVF_DOWN_PENDING)
-		return 0;
+	mutex_lock(&adapter->crit_lock);
 
-	while (!mutex_trylock(&adapter->crit_lock))
-		usleep_range(500, 1000);
+	if (adapter->state <= __IAVF_DOWN_PENDING) {
+		mutex_unlock(&adapter->crit_lock);
+		return 0;
+	}
 
 	set_bit(__IAVF_VSI_DOWN, adapter->vsi.state);
 	if (CLIENT_ENABLED(adapter))
@@ -3853,8 +3904,11 @@ static int iavf_change_mtu(struct net_device *netdev, int new_mtu)
 		iavf_notify_client_l2_params(&adapter->vsi);
 		adapter->flags |= IAVF_FLAG_SERVICE_CLIENT_REQUESTED;
 	}
-	adapter->flags |= IAVF_FLAG_RESET_NEEDED;
-	queue_work(iavf_wq, &adapter->reset_task);
+
+	if (netif_running(netdev)) {
+		adapter->flags |= IAVF_FLAG_RESET_NEEDED;
+		queue_work(iavf_wq, &adapter->reset_task);
+	}
 
 	return 0;
 }
@@ -4431,7 +4485,6 @@ static int iavf_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	 */
 	mutex_init(&adapter->crit_lock);
 	mutex_init(&adapter->client_lock);
-	mutex_init(&adapter->remove_lock);
 	mutex_init(&hw->aq.asq_mutex);
 	mutex_init(&hw->aq.arq_mutex);
 
@@ -4547,7 +4600,6 @@ static int __maybe_unused iavf_resume(struct device *dev_d)
 static void iavf_remove(struct pci_dev *pdev)
 {
 	struct iavf_adapter *adapter = iavf_pdev_to_adapter(pdev);
-	enum iavf_state_t prev_state = adapter->last_state;
 	struct net_device *netdev = adapter->netdev;
 	struct iavf_fdir_fltr *fdir, *fdirtmp;
 	struct iavf_vlan_filter *vlf, *vlftmp;
@@ -4556,14 +4608,30 @@ static void iavf_remove(struct pci_dev *pdev)
 	struct iavf_cloud_filter *cf, *cftmp;
 	struct iavf_hw *hw = &adapter->hw;
 	int err;
-	/* Indicate we are in remove and not to run reset_task */
-	mutex_lock(&adapter->remove_lock);
-	cancel_work_sync(&adapter->reset_task);
+
+	set_bit(__IAVF_IN_REMOVE_TASK, &adapter->crit_section);
+	/* Wait until port initialization is complete.
+	 * There are flows where register/unregister netdev may race.
+	 */
+	while (1) {
+		mutex_lock(&adapter->crit_lock);
+		if (adapter->state == __IAVF_RUNNING ||
+		    adapter->state == __IAVF_DOWN ||
+		    adapter->state == __IAVF_INIT_FAILED) {
+			mutex_unlock(&adapter->crit_lock);
+			break;
+		}
+
+		mutex_unlock(&adapter->crit_lock);
+		usleep_range(500, 1000);
+	}
 	cancel_delayed_work_sync(&adapter->watchdog_task);
-	cancel_delayed_work_sync(&adapter->client_task);
+
 	if (adapter->netdev_registered) {
-		unregister_netdev(netdev);
+		rtnl_lock();
+		unregister_netdevice(netdev);
 		adapter->netdev_registered = false;
+		rtnl_unlock();
 	}
 	if (CLIENT_ALLOWED(adapter)) {
 		err = iavf_lan_del_device(adapter);
@@ -4572,6 +4640,10 @@ static void iavf_remove(struct pci_dev *pdev)
 				 err);
 	}
 
+	mutex_lock(&adapter->crit_lock);
+	dev_info(&adapter->pdev->dev, "Remove device\n");
+	iavf_change_state(adapter, __IAVF_REMOVE);
+
 	iavf_request_reset(adapter);
 	msleep(50);
 	/* If the FW isn't responding, kick it once, but only once. */
@@ -4579,37 +4651,24 @@ static void iavf_remove(struct pci_dev *pdev)
 		iavf_request_reset(adapter);
 		msleep(50);
 	}
-	if (iavf_lock_timeout(&adapter->crit_lock, 5000))
-		dev_warn(&adapter->pdev->dev, "failed to acquire crit_lock in %s\n", __FUNCTION__);
 
-	dev_info(&adapter->pdev->dev, "Removing device\n");
+	iavf_misc_irq_disable(adapter);
 	/* Shut down all the garbage mashers on the detention level */
-	iavf_change_state(adapter, __IAVF_REMOVE);
+	cancel_work_sync(&adapter->reset_task);
+	cancel_delayed_work_sync(&adapter->watchdog_task);
+	cancel_work_sync(&adapter->adminq_task);
+	cancel_delayed_work_sync(&adapter->client_task);
+
 	adapter->aq_required = 0;
 	adapter->flags &= ~IAVF_FLAG_REINIT_ITR_NEEDED;
 
 	iavf_free_all_tx_resources(adapter);
 	iavf_free_all_rx_resources(adapter);
-	iavf_misc_irq_disable(adapter);
 	iavf_free_misc_irq(adapter);
 
-	/* In case we enter iavf_remove from erroneous state, free traffic irqs
-	 * here, so as to not cause a kernel crash, when calling
-	 * iavf_reset_interrupt_capability.
-	 */
-	if ((adapter->last_state == __IAVF_RESETTING &&
-	     prev_state != __IAVF_DOWN) ||
-	    (adapter->last_state == __IAVF_RUNNING &&
-	     !(netdev->flags & IFF_UP)))
-		iavf_free_traffic_irqs(adapter);
-
 	iavf_reset_interrupt_capability(adapter);
 	iavf_free_q_vectors(adapter);
 
-	cancel_delayed_work_sync(&adapter->watchdog_task);
-
-	cancel_work_sync(&adapter->adminq_task);
-
 	iavf_free_rss(adapter);
 
 	if (hw->aq.asq.count)
@@ -4621,8 +4680,6 @@ static void iavf_remove(struct pci_dev *pdev)
 	mutex_destroy(&adapter->client_lock);
 	mutex_unlock(&adapter->crit_lock);
 	mutex_destroy(&adapter->crit_lock);
-	mutex_unlock(&adapter->remove_lock);
-	mutex_destroy(&adapter->remove_lock);
 
 	iounmap(hw->hw_addr);
 	pci_release_regions(pdev);
diff --git a/drivers/net/ethernet/intel/iavf/iavf_virtchnl.c b/drivers/net/ethernet/intel/iavf/iavf_virtchnl.c
index 5ee1d118fd30..88844d68e150 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_virtchnl.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_virtchnl.c
@@ -2146,29 +2146,7 @@ void iavf_virtchnl_completion(struct iavf_adapter *adapter,
 				     sizeof(adapter->vlan_v2_caps)));
 
 		iavf_process_config(adapter);
-
-		/* unlock crit_lock before acquiring rtnl_lock as other
-		 * processes holding rtnl_lock could be waiting for the same
-		 * crit_lock
-		 */
-		mutex_unlock(&adapter->crit_lock);
-		/* VLAN capabilities can change during VFR, so make sure to
-		 * update the netdev features with the new capabilities
-		 */
-		rtnl_lock();
-		netdev_update_features(netdev);
-		rtnl_unlock();
-		if (iavf_lock_timeout(&adapter->crit_lock, 10000))
-			dev_warn(&adapter->pdev->dev, "failed to acquire crit_lock in %s\n",
-				 __FUNCTION__);
-
-		/* Request VLAN offload settings */
-		if (VLAN_V2_ALLOWED(adapter))
-			iavf_set_vlan_offload_features(adapter, 0,
-						       netdev->features);
-
-		iavf_set_queue_vlan_tag_loc(adapter);
-
+		adapter->flags |= IAVF_FLAG_SETUP_NETDEV_FEATURES;
 		}
 		break;
 	case VIRTCHNL_OP_ENABLE_QUEUES: