[PATCH AUTOSEL 4.19 49/68] net/ibmnvic: Fix deadlock problem in reset

[PATCH AUTOSEL 4.19 49/68] net/ibmnvic: Fix deadlock problem in reset

[Sasha Levin]

From: Juliet Kim <julietk@linux.vnet.ibm.com>

[ Upstream commit a5681e20b541a507c7d4fd48ae4a4040d32ee1ef ]

This patch changes to use rtnl_lock only during a reset to avoid
deadlock that could occur when a thread operating close is holding
rtnl_lock and waiting for reset_lock acquired by another thread,
which is waiting for rtnl_lock in order to set the number of tx/rx
queues during a reset.

Also, we now setting the number of tx/rx queues during a soft reset
for failover or LPM events.

Signed-off-by: Juliet Kim <julietk@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/ethernet/ibm/ibmvnic.c | 59 +++++++++++-------------------
 drivers/net/ethernet/ibm/ibmvnic.h |  2 +-
 2 files changed, 22 insertions(+), 39 deletions(-)

diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
index 7661064c815b..a646de07cbdc 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -1103,20 +1103,15 @@ static int ibmvnic_open(struct net_device *netdev)
 		return 0;
 	}
 
-	mutex_lock(&adapter->reset_lock);
-
 	if (adapter->state != VNIC_CLOSED) {
 		rc = ibmvnic_login(netdev);
-		if (rc) {
-			mutex_unlock(&adapter->reset_lock);
+		if (rc)
 			return rc;
-		}
 
 		rc = init_resources(adapter);
 		if (rc) {
 			netdev_err(netdev, "failed to initialize resources\n");
 			release_resources(adapter);
-			mutex_unlock(&adapter->reset_lock);
 			return rc;
 		}
 	}
@@ -1124,8 +1119,6 @@ static int ibmvnic_open(struct net_device *netdev)
 	rc = __ibmvnic_open(netdev);
 	netif_carrier_on(netdev);
 
-	mutex_unlock(&adapter->reset_lock);
-
 	return rc;
 }
 
@@ -1269,10 +1262,8 @@ static int ibmvnic_close(struct net_device *netdev)
 		return 0;
 	}
 
-	mutex_lock(&adapter->reset_lock);
 	rc = __ibmvnic_close(netdev);
 	ibmvnic_cleanup(netdev);
-	mutex_unlock(&adapter->reset_lock);
 
 	return rc;
 }
@@ -1820,20 +1811,15 @@ static int do_reset(struct ibmvnic_adapter *adapter,
 				return rc;
 		} else if (adapter->req_rx_queues != old_num_rx_queues ||
 			   adapter->req_tx_queues != old_num_tx_queues) {
-			adapter->map_id = 1;
 			release_rx_pools(adapter);
 			release_tx_pools(adapter);
-			rc = init_rx_pools(netdev);
-			if (rc)
-				return rc;
-			rc = init_tx_pools(netdev);
-			if (rc)
-				return rc;
-
 			release_napi(adapter);
-			rc = init_napi(adapter);
+			release_vpd_data(adapter);
+
+			rc = init_resources(adapter);
 			if (rc)
 				return rc;
+
 		} else {
 			rc = reset_tx_pools(adapter);
 			if (rc)
@@ -1917,17 +1903,8 @@ static int do_hard_reset(struct ibmvnic_adapter *adapter,
 		adapter->state = VNIC_PROBED;
 		return 0;
 	}
-	/* netif_set_real_num_xx_queues needs to take rtnl lock here
-	 * unless wait_for_reset is set, in which case the rtnl lock
-	 * has already been taken before initializing the reset
-	 */
-	if (!adapter->wait_for_reset) {
-		rtnl_lock();
-		rc = init_resources(adapter);
-		rtnl_unlock();
-	} else {
-		rc = init_resources(adapter);
-	}
+
+	rc = init_resources(adapter);
 	if (rc)
 		return rc;
 
@@ -1986,13 +1963,21 @@ static void __ibmvnic_reset(struct work_struct *work)
 	struct ibmvnic_rwi *rwi;
 	struct ibmvnic_adapter *adapter;
 	struct net_device *netdev;
+	bool we_lock_rtnl = false;
 	u32 reset_state;
 	int rc = 0;
 
 	adapter = container_of(work, struct ibmvnic_adapter, ibmvnic_reset);
 	netdev = adapter->netdev;
 
-	mutex_lock(&adapter->reset_lock);
+	/* netif_set_real_num_xx_queues needs to take rtnl lock here
+	 * unless wait_for_reset is set, in which case the rtnl lock
+	 * has already been taken before initializing the reset
+	 */
+	if (!adapter->wait_for_reset) {
+		rtnl_lock();
+		we_lock_rtnl = true;
+	}
 	reset_state = adapter->state;
 
 	rwi = get_next_rwi(adapter);
@@ -2020,12 +2005,11 @@ static void __ibmvnic_reset(struct work_struct *work)
 	if (rc) {
 		netdev_dbg(adapter->netdev, "Reset failed\n");
 		free_all_rwi(adapter);
-		mutex_unlock(&adapter->reset_lock);
-		return;
 	}
 
 	adapter->resetting = false;
-	mutex_unlock(&adapter->reset_lock);
+	if (we_lock_rtnl)
+		rtnl_unlock();
 }
 
 static int ibmvnic_reset(struct ibmvnic_adapter *adapter,
@@ -4709,7 +4693,6 @@ static int ibmvnic_probe(struct vio_dev *dev, const struct vio_device_id *id)
 
 	INIT_WORK(&adapter->ibmvnic_reset, __ibmvnic_reset);
 	INIT_LIST_HEAD(&adapter->rwi_list);
-	mutex_init(&adapter->reset_lock);
 	mutex_init(&adapter->rwi_lock);
 	adapter->resetting = false;
 
@@ -4781,8 +4764,8 @@ static int ibmvnic_remove(struct vio_dev *dev)
 	struct ibmvnic_adapter *adapter = netdev_priv(netdev);
 
 	adapter->state = VNIC_REMOVING;
-	unregister_netdev(netdev);
-	mutex_lock(&adapter->reset_lock);
+	rtnl_lock();
+	unregister_netdevice(netdev);
 
 	release_resources(adapter);
 	release_sub_crqs(adapter, 1);
@@ -4793,7 +4776,7 @@ static int ibmvnic_remove(struct vio_dev *dev)
 
 	adapter->state = VNIC_REMOVED;
 
-	mutex_unlock(&adapter->reset_lock);
+	rtnl_unlock();
 	device_remove_file(&dev->dev, &dev_attr_failover);
 	free_netdev(netdev);
 	dev_set_drvdata(&dev->dev, NULL);
diff --git a/drivers/net/ethernet/ibm/ibmvnic.h b/drivers/net/ethernet/ibm/ibmvnic.h
index f06eec145ca6..735f481b1870 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.h
+++ b/drivers/net/ethernet/ibm/ibmvnic.h
@@ -1068,7 +1068,7 @@ struct ibmvnic_adapter {
 	struct tasklet_struct tasklet;
 	enum vnic_state state;
 	enum ibmvnic_reset_reason reset_reason;
-	struct mutex reset_lock, rwi_lock;
+	struct mutex rwi_lock;
 	struct list_head rwi_list;
 	struct work_struct ibmvnic_reset;
 	bool resetting;
-- 
2.17.1

[PATCH AUTOSEL 4.19 61/68] ibmvnic: Fix RX queue buffer cleanup

[Sasha Levin]

From: Thomas Falcon <tlfalcon@linux.ibm.com>

[ Upstream commit b7cdec3d699db2e5985ad39de0f25d3b6111928e ]

The wrong index is used when cleaning up RX buffer objects during release
of RX queues. Update to use the correct index counter.

Signed-off-by: Thomas Falcon <tlfalcon@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/ethernet/ibm/ibmvnic.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
index a646de07cbdc..f1d4d7a1278b 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -485,8 +485,8 @@ static void release_rx_pools(struct ibmvnic_adapter *adapter)
 
 		for (j = 0; j < rx_pool->size; j++) {
 			if (rx_pool->rx_buff[j].skb) {
-				dev_kfree_skb_any(rx_pool->rx_buff[i].skb);
-				rx_pool->rx_buff[i].skb = NULL;
+				dev_kfree_skb_any(rx_pool->rx_buff[j].skb);
+				rx_pool->rx_buff[j].skb = NULL;
 			}
 		}
 
-- 
2.17.1

[PATCH AUTOSEL 4.19 62/68] ibmvnic: Update driver queues after change in ring size support

[Sasha Levin]

From: Thomas Falcon <tlfalcon@linux.ibm.com>

[ Upstream commit 5bf032ef08e6a110edc1e3bfb3c66a208fb55125 ]

During device reset, queue memory is not being updated to accommodate
changes in ring buffer sizes supported by backing hardware. Track
any differences in ring buffer sizes following the reset and update
queue memory when possible.

Signed-off-by: Thomas Falcon <tlfalcon@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/ethernet/ibm/ibmvnic.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
index f1d4d7a1278b..5ab21a1b5444 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -1737,6 +1737,7 @@ static int do_reset(struct ibmvnic_adapter *adapter,
 		    struct ibmvnic_rwi *rwi, u32 reset_state)
 {
 	u64 old_num_rx_queues, old_num_tx_queues;
+	u64 old_num_rx_slots, old_num_tx_slots;
 	struct net_device *netdev = adapter->netdev;
 	int i, rc;
 
@@ -1748,6 +1749,8 @@ static int do_reset(struct ibmvnic_adapter *adapter,
 
 	old_num_rx_queues = adapter->req_rx_queues;
 	old_num_tx_queues = adapter->req_tx_queues;
+	old_num_rx_slots = adapter->req_rx_add_entries_per_subcrq;
+	old_num_tx_slots = adapter->req_tx_entries_per_subcrq;
 
 	ibmvnic_cleanup(netdev);
 
@@ -1810,7 +1813,11 @@ static int do_reset(struct ibmvnic_adapter *adapter,
 			if (rc)
 				return rc;
 		} else if (adapter->req_rx_queues != old_num_rx_queues ||
-			   adapter->req_tx_queues != old_num_tx_queues) {
+			   adapter->req_tx_queues != old_num_tx_queues ||
+			   adapter->req_rx_add_entries_per_subcrq !=
+							old_num_rx_slots ||
+			   adapter->req_tx_entries_per_subcrq !=
+							old_num_tx_slots) {
 			release_rx_pools(adapter);
 			release_tx_pools(adapter);
 			release_napi(adapter);
-- 
2.17.1