4.19-stable review patch. If anyone has any objections, please let me know.
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[ 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;