[PATCH 6.1 252/313] iavf: fix temporary deadlock and failure to set MAC address

From: Michal Schmidt mschmidt@redhat.com

[ Upstream commit 4411a608f7c8df000cb1a9f7881982dd8e10839a ]

We are seeing an issue where setting the MAC address on iavf fails with EAGAIN after the 2.5s timeout expires in iavf_set_mac().

There is the following deadlock scenario:

iavf_set_mac(), holding rtnl_lock, waits on: iavf_watchdog_task (within iavf_wq) to send a message to the PF, and iavf_adminq_task (within iavf_wq) to receive a response from the PF. In this adapter state (>=__IAVF_DOWN), these tasks do not need to take rtnl_lock, but iavf_wq is a global single-threaded workqueue, so they may get stuck waiting for another adapter's iavf_watchdog_task to run iavf_init_config_adapter(), which does take rtnl_lock.

The deadlock resolves itself by the timeout in iavf_set_mac(), which results in EAGAIN returned to userspace.

Let's break the deadlock loop by changing iavf_wq into a per-adapter workqueue, so that one adapter's tasks are not blocked by another's.

Fixes: 35a2443d0910 ("iavf: Add waiting for response from PF in set mac") Co-developed-by: Ivan Vecera ivecera@redhat.com Signed-off-by: Ivan Vecera ivecera@redhat.com Signed-off-by: Michal Schmidt mschmidt@redhat.com Tested-by: Rafal Romanowski rafal.romanowski@intel.com Signed-off-by: Tony Nguyen anthony.l.nguyen@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/intel/iavf/iavf.h | 2 +- .../net/ethernet/intel/iavf/iavf_ethtool.c | 10 +-- drivers/net/ethernet/intel/iavf/iavf_main.c | 86 +++++++++---------- .../net/ethernet/intel/iavf/iavf_virtchnl.c | 2 +- 4 files changed, 49 insertions(+), 51 deletions(-)

diff --git a/drivers/net/ethernet/intel/iavf/iavf.h b/drivers/net/ethernet/intel/iavf/iavf.h index 0d1bab4ac1b0..2a9f1eeeb701 100644 --- a/drivers/net/ethernet/intel/iavf/iavf.h +++ b/drivers/net/ethernet/intel/iavf/iavf.h @@ -249,6 +249,7 @@ struct iavf_cloud_filter {

/* board specific private data structure */ struct iavf_adapter { + struct workqueue_struct *wq; struct work_struct reset_task; struct work_struct adminq_task; struct delayed_work client_task; @@ -459,7 +460,6 @@ struct iavf_device {

/* needed by iavf_ethtool.c */ extern char iavf_driver_name[]; -extern struct workqueue_struct *iavf_wq;

static inline const char *iavf_state_str(enum iavf_state_t state) { diff --git a/drivers/net/ethernet/intel/iavf/iavf_ethtool.c b/drivers/net/ethernet/intel/iavf/iavf_ethtool.c index a056e1545615..83cfc54a4706 100644 --- a/drivers/net/ethernet/intel/iavf/iavf_ethtool.c +++ b/drivers/net/ethernet/intel/iavf/iavf_ethtool.c @@ -532,7 +532,7 @@ static int iavf_set_priv_flags(struct net_device *netdev, u32 flags) if (changed_flags & IAVF_FLAG_LEGACY_RX) { if (netif_running(netdev)) { adapter->flags |= IAVF_FLAG_RESET_NEEDED; - queue_work(iavf_wq, &adapter->reset_task); + queue_work(adapter->wq, &adapter->reset_task); } }

@@ -672,7 +672,7 @@ static int iavf_set_ringparam(struct net_device *netdev,

if (netif_running(netdev)) { adapter->flags |= IAVF_FLAG_RESET_NEEDED; - queue_work(iavf_wq, &adapter->reset_task); + queue_work(adapter->wq, &adapter->reset_task); }

return 0; @@ -1433,7 +1433,7 @@ static int iavf_add_fdir_ethtool(struct iavf_adapter *adapter, struct ethtool_rx adapter->aq_required |= IAVF_FLAG_AQ_ADD_FDIR_FILTER; spin_unlock_bh(&adapter->fdir_fltr_lock);

- mod_delayed_work(iavf_wq, &adapter->watchdog_task, 0); + mod_delayed_work(adapter->wq, &adapter->watchdog_task, 0);

ret: if (err && fltr) @@ -1474,7 +1474,7 @@ static int iavf_del_fdir_ethtool(struct iavf_adapter *adapter, struct ethtool_rx spin_unlock_bh(&adapter->fdir_fltr_lock);

if (fltr && fltr->state == IAVF_FDIR_FLTR_DEL_REQUEST) - mod_delayed_work(iavf_wq, &adapter->watchdog_task, 0); + mod_delayed_work(adapter->wq, &adapter->watchdog_task, 0);

return err; } @@ -1658,7 +1658,7 @@ iavf_set_adv_rss_hash_opt(struct iavf_adapter *adapter, spin_unlock_bh(&adapter->adv_rss_lock);

if (!err) - mod_delayed_work(iavf_wq, &adapter->watchdog_task, 0); + mod_delayed_work(adapter->wq, &adapter->watchdog_task, 0);

mutex_unlock(&adapter->crit_lock);

diff --git a/drivers/net/ethernet/intel/iavf/iavf_main.c b/drivers/net/ethernet/intel/iavf/iavf_main.c index 260c55951c28..efc7735ece30 100644 --- a/drivers/net/ethernet/intel/iavf/iavf_main.c +++ b/drivers/net/ethernet/intel/iavf/iavf_main.c @@ -49,7 +49,6 @@ MODULE_DESCRIPTION("Intel(R) Ethernet Adaptive Virtual Function Network Driver") MODULE_LICENSE("GPL v2");

static const struct net_device_ops iavf_netdev_ops; -struct workqueue_struct *iavf_wq;

int iavf_status_to_errno(enum iavf_status status) { @@ -277,7 +276,7 @@ void iavf_schedule_reset(struct iavf_adapter *adapter) if (!(adapter->flags & (IAVF_FLAG_RESET_PENDING | IAVF_FLAG_RESET_NEEDED))) { adapter->flags |= IAVF_FLAG_RESET_NEEDED; - queue_work(iavf_wq, &adapter->reset_task); + queue_work(adapter->wq, &adapter->reset_task); } }

@@ -291,7 +290,7 @@ void iavf_schedule_reset(struct iavf_adapter *adapter) void iavf_schedule_request_stats(struct iavf_adapter *adapter) { adapter->aq_required |= IAVF_FLAG_AQ_REQUEST_STATS; - mod_delayed_work(iavf_wq, &adapter->watchdog_task, 0); + mod_delayed_work(adapter->wq, &adapter->watchdog_task, 0); }

/** @@ -411,7 +410,7 @@ static irqreturn_t iavf_msix_aq(int irq, void *data)

if (adapter->state != __IAVF_REMOVE) /* schedule work on the private workqueue */ - queue_work(iavf_wq, &adapter->adminq_task); + queue_work(adapter->wq, &adapter->adminq_task);

return IRQ_HANDLED; } @@ -1034,7 +1033,7 @@ int iavf_replace_primary_mac(struct iavf_adapter *adapter,

/* schedule the watchdog task to immediately process the request */ if (f) { - queue_work(iavf_wq, &adapter->watchdog_task.work); + queue_work(adapter->wq, &adapter->watchdog_task.work); return 0; } return -ENOMEM; @@ -1257,7 +1256,7 @@ static void iavf_up_complete(struct iavf_adapter *adapter) adapter->aq_required |= IAVF_FLAG_AQ_ENABLE_QUEUES; if (CLIENT_ENABLED(adapter)) adapter->flags |= IAVF_FLAG_CLIENT_NEEDS_OPEN; - mod_delayed_work(iavf_wq, &adapter->watchdog_task, 0); + mod_delayed_work(adapter->wq, &adapter->watchdog_task, 0); }

/** @@ -1414,7 +1413,7 @@ void iavf_down(struct iavf_adapter *adapter) adapter->aq_required |= IAVF_FLAG_AQ_DISABLE_QUEUES; }

- mod_delayed_work(iavf_wq, &adapter->watchdog_task, 0); + mod_delayed_work(adapter->wq, &adapter->watchdog_task, 0); }

/** @@ -2248,7 +2247,7 @@ iavf_set_vlan_offload_features(struct iavf_adapter *adapter,

if (aq_required) { adapter->aq_required |= aq_required; - mod_delayed_work(iavf_wq, &adapter->watchdog_task, 0); + mod_delayed_work(adapter->wq, &adapter->watchdog_task, 0); } }

@@ -2700,7 +2699,7 @@ static void iavf_watchdog_task(struct work_struct *work) adapter->aq_required = 0; adapter->current_op = VIRTCHNL_OP_UNKNOWN; mutex_unlock(&adapter->crit_lock); - queue_work(iavf_wq, &adapter->reset_task); + queue_work(adapter->wq, &adapter->reset_task); return; }

@@ -2708,31 +2707,31 @@ static void iavf_watchdog_task(struct work_struct *work) case __IAVF_STARTUP: iavf_startup(adapter); mutex_unlock(&adapter->crit_lock); - queue_delayed_work(iavf_wq, &adapter->watchdog_task, + queue_delayed_work(adapter->wq, &adapter->watchdog_task, msecs_to_jiffies(30)); return; case __IAVF_INIT_VERSION_CHECK: iavf_init_version_check(adapter); mutex_unlock(&adapter->crit_lock); - queue_delayed_work(iavf_wq, &adapter->watchdog_task, + queue_delayed_work(adapter->wq, &adapter->watchdog_task, msecs_to_jiffies(30)); return; case __IAVF_INIT_GET_RESOURCES: iavf_init_get_resources(adapter); mutex_unlock(&adapter->crit_lock); - queue_delayed_work(iavf_wq, &adapter->watchdog_task, + queue_delayed_work(adapter->wq, &adapter->watchdog_task, msecs_to_jiffies(1)); return; case __IAVF_INIT_EXTENDED_CAPS: iavf_init_process_extended_caps(adapter); mutex_unlock(&adapter->crit_lock); - queue_delayed_work(iavf_wq, &adapter->watchdog_task, + queue_delayed_work(adapter->wq, &adapter->watchdog_task, msecs_to_jiffies(1)); return; case __IAVF_INIT_CONFIG_ADAPTER: iavf_init_config_adapter(adapter); mutex_unlock(&adapter->crit_lock); - queue_delayed_work(iavf_wq, &adapter->watchdog_task, + queue_delayed_work(adapter->wq, &adapter->watchdog_task, msecs_to_jiffies(1)); return; case __IAVF_INIT_FAILED: @@ -2751,14 +2750,14 @@ static void iavf_watchdog_task(struct work_struct *work) adapter->flags |= IAVF_FLAG_PF_COMMS_FAILED; iavf_shutdown_adminq(hw); mutex_unlock(&adapter->crit_lock); - queue_delayed_work(iavf_wq, + queue_delayed_work(adapter->wq, &adapter->watchdog_task, (5 * HZ)); return; } /* Try again from failed step*/ iavf_change_state(adapter, adapter->last_state); mutex_unlock(&adapter->crit_lock); - queue_delayed_work(iavf_wq, &adapter->watchdog_task, HZ); + queue_delayed_work(adapter->wq, &adapter->watchdog_task, HZ); return; case __IAVF_COMM_FAILED: if (test_bit(__IAVF_IN_REMOVE_TASK, @@ -2789,13 +2788,14 @@ static void iavf_watchdog_task(struct work_struct *work) adapter->aq_required = 0; adapter->current_op = VIRTCHNL_OP_UNKNOWN; mutex_unlock(&adapter->crit_lock); - queue_delayed_work(iavf_wq, + queue_delayed_work(adapter->wq, &adapter->watchdog_task, msecs_to_jiffies(10)); return; case __IAVF_RESETTING: mutex_unlock(&adapter->crit_lock); - queue_delayed_work(iavf_wq, &adapter->watchdog_task, HZ * 2); + queue_delayed_work(adapter->wq, &adapter->watchdog_task, + HZ * 2); return; case __IAVF_DOWN: case __IAVF_DOWN_PENDING: @@ -2834,9 +2834,9 @@ static void iavf_watchdog_task(struct work_struct *work) adapter->aq_required = 0; adapter->current_op = VIRTCHNL_OP_UNKNOWN; dev_err(&adapter->pdev->dev, "Hardware reset detected\n"); - queue_work(iavf_wq, &adapter->reset_task); + queue_work(adapter->wq, &adapter->reset_task); mutex_unlock(&adapter->crit_lock); - queue_delayed_work(iavf_wq, + queue_delayed_work(adapter->wq, &adapter->watchdog_task, HZ * 2); return; } @@ -2845,12 +2845,13 @@ static void iavf_watchdog_task(struct work_struct *work) mutex_unlock(&adapter->crit_lock); restart_watchdog: if (adapter->state >= __IAVF_DOWN) - queue_work(iavf_wq, &adapter->adminq_task); + queue_work(adapter->wq, &adapter->adminq_task); if (adapter->aq_required) - queue_delayed_work(iavf_wq, &adapter->watchdog_task, + queue_delayed_work(adapter->wq, &adapter->watchdog_task, msecs_to_jiffies(20)); else - queue_delayed_work(iavf_wq, &adapter->watchdog_task, HZ * 2); + queue_delayed_work(adapter->wq, &adapter->watchdog_task, + HZ * 2); }

/** @@ -2952,7 +2953,7 @@ static void iavf_reset_task(struct work_struct *work) */ if (!mutex_trylock(&adapter->crit_lock)) { if (adapter->state != __IAVF_REMOVE) - queue_work(iavf_wq, &adapter->reset_task); + queue_work(adapter->wq, &adapter->reset_task);

goto reset_finish; } @@ -3116,7 +3117,7 @@ static void iavf_reset_task(struct work_struct *work) bitmap_clear(adapter->vsi.active_cvlans, 0, VLAN_N_VID); bitmap_clear(adapter->vsi.active_svlans, 0, VLAN_N_VID);

- mod_delayed_work(iavf_wq, &adapter->watchdog_task, 2); + mod_delayed_work(adapter->wq, &adapter->watchdog_task, 2);

/* We were running when the reset started, so we need to restore some * state here. @@ -3208,7 +3209,7 @@ static void iavf_adminq_task(struct work_struct *work) if (adapter->state == __IAVF_REMOVE) return;

- queue_work(iavf_wq, &adapter->adminq_task); + queue_work(adapter->wq, &adapter->adminq_task); goto out; }

@@ -4349,7 +4350,7 @@ static int iavf_change_mtu(struct net_device *netdev, int new_mtu)

if (netif_running(netdev)) { adapter->flags |= IAVF_FLAG_RESET_NEEDED; - queue_work(iavf_wq, &adapter->reset_task); + queue_work(adapter->wq, &adapter->reset_task); }

return 0; @@ -4898,6 +4899,13 @@ static int iavf_probe(struct pci_dev *pdev, const struct pci_device_id *ent) hw = &adapter->hw; hw->back = adapter;

+ adapter->wq = alloc_ordered_workqueue("%s", WQ_MEM_RECLAIM, + iavf_driver_name); + if (!adapter->wq) { + err = -ENOMEM; + goto err_alloc_wq; + } + adapter->msg_enable = BIT(DEFAULT_DEBUG_LEVEL_SHIFT) - 1; iavf_change_state(adapter, __IAVF_STARTUP);

@@ -4942,7 +4950,7 @@ static int iavf_probe(struct pci_dev *pdev, const struct pci_device_id *ent) INIT_WORK(&adapter->adminq_task, iavf_adminq_task); INIT_DELAYED_WORK(&adapter->watchdog_task, iavf_watchdog_task); INIT_DELAYED_WORK(&adapter->client_task, iavf_client_task); - queue_delayed_work(iavf_wq, &adapter->watchdog_task, + queue_delayed_work(adapter->wq, &adapter->watchdog_task, msecs_to_jiffies(5 * (pdev->devfn & 0x07)));

/* Setup the wait queue for indicating transition to down status */ @@ -4954,6 +4962,8 @@ static int iavf_probe(struct pci_dev *pdev, const struct pci_device_id *ent) return 0;

err_ioremap: + destroy_workqueue(adapter->wq); +err_alloc_wq: free_netdev(netdev); err_alloc_etherdev: pci_disable_pcie_error_reporting(pdev); @@ -5023,7 +5033,7 @@ static int __maybe_unused iavf_resume(struct device *dev_d) return err; }

- queue_work(iavf_wq, &adapter->reset_task); + queue_work(adapter->wq, &adapter->reset_task);

netif_device_attach(adapter->netdev);

@@ -5170,6 +5180,8 @@ static void iavf_remove(struct pci_dev *pdev) } spin_unlock_bh(&adapter->adv_rss_lock);

+ destroy_workqueue(adapter->wq); + free_netdev(netdev);

pci_disable_pcie_error_reporting(pdev); @@ -5196,24 +5208,11 @@ static struct pci_driver iavf_driver = { **/ static int __init iavf_init_module(void) { - int ret; - pr_info("iavf: %s\n", iavf_driver_string);

pr_info("%s\n", iavf_copyright);

- iavf_wq = alloc_workqueue("%s", WQ_UNBOUND | WQ_MEM_RECLAIM, 1, - iavf_driver_name); - if (!iavf_wq) { - pr_err("%s: Failed to create workqueue\n", iavf_driver_name); - return -ENOMEM; - } - - ret = pci_register_driver(&iavf_driver); - if (ret) - destroy_workqueue(iavf_wq); - - return ret; + return pci_register_driver(&iavf_driver); }

module_init(iavf_init_module); @@ -5227,7 +5226,6 @@ module_init(iavf_init_module); static void __exit iavf_exit_module(void) { pci_unregister_driver(&iavf_driver); - destroy_workqueue(iavf_wq); }

module_exit(iavf_exit_module); diff --git a/drivers/net/ethernet/intel/iavf/iavf_virtchnl.c b/drivers/net/ethernet/intel/iavf/iavf_virtchnl.c index 24a701fd140e..0752fd67c96e 100644 --- a/drivers/net/ethernet/intel/iavf/iavf_virtchnl.c +++ b/drivers/net/ethernet/intel/iavf/iavf_virtchnl.c @@ -1952,7 +1952,7 @@ void iavf_virtchnl_completion(struct iavf_adapter *adapter, if (!(adapter->flags & IAVF_FLAG_RESET_PENDING)) { adapter->flags |= IAVF_FLAG_RESET_PENDING; dev_info(&adapter->pdev->dev, "Scheduling reset task\n"); - queue_work(iavf_wq, &adapter->reset_task); + queue_work(adapter->wq, &adapter->reset_task); } break; default: