From 10a54d8196d11f6cc0db2f71249f93854cb9fe55 Mon Sep 17 00:00:00 2001 From: Luca Coelho Date: Tue, 22 Aug 2017 10:37:29 +0300 Subject: [PATCH] iwlwifi: pcie: move rx workqueue initialization to iwl_trans_pcie_alloc() Work queues cannot be allocated when a mutex is held because the mutex may be in use and that would make it sleep. Doing so generates the following splat with 4.13+: [ 19.513298] ====================================================== [ 19.513429] WARNING: possible circular locking dependency detected [ 19.513557] 4.13.0-rc5+ #6 Not tainted [ 19.513638] ------------------------------------------------------ [ 19.513767] cpuhp/0/12 is trying to acquire lock: [ 19.513867] (&tz->lock){+.+.+.}, at: [] thermal_zone_get_temp+0x5b/0xb0 [ 19.514047] [ 19.514047] but task is already holding lock: [ 19.514166] (cpuhp_state){+.+.+.}, at: [] cpuhp_thread_fun+0x3a/0x210 [ 19.514338] [ 19.514338] which lock already depends on the new lock. This lock dependency already existed with previous kernel versions, but it was not detected until commit 49dfe2a67797 ("cpuhotplug: Link lock stacks for hotplug callbacks") was introduced. Reported-by: David Weinehall Reported-by: Jiri Kosina Signed-off-by: Luca Coelho Signed-off-by: Kalle Valo --- drivers/net/wireless/intel/iwlwifi/pcie/internal.h | 2 ++ drivers/net/wireless/intel/iwlwifi/pcie/rx.c | 10 +--------- drivers/net/wireless/intel/iwlwifi/pcie/trans.c | 9 +++++++++ 3 files changed, 12 insertions(+), 9 deletions(-) diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/internal.h b/drivers/net/wireless/intel/iwlwifi/pcie/internal.h index fa315d84e98e..a1ea9ef97ed9 100644 --- a/drivers/net/wireless/intel/iwlwifi/pcie/internal.h +++ b/drivers/net/wireless/intel/iwlwifi/pcie/internal.h @@ -787,6 +787,8 @@ int iwl_pci_fw_enter_d0i3(struct iwl_trans *trans); void iwl_pcie_enable_rx_wake(struct iwl_trans *trans, bool enable); +void iwl_pcie_rx_allocator_work(struct work_struct *data); + /* common functions that are used by gen2 transport */ void iwl_pcie_apm_config(struct iwl_trans *trans); int iwl_pcie_prepare_card_hw(struct iwl_trans *trans); diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/rx.c b/drivers/net/wireless/intel/iwlwifi/pcie/rx.c index 351c4423125a..942736d3fa75 100644 --- a/drivers/net/wireless/intel/iwlwifi/pcie/rx.c +++ b/drivers/net/wireless/intel/iwlwifi/pcie/rx.c @@ -597,7 +597,7 @@ static void iwl_pcie_rx_allocator_get(struct iwl_trans *trans, rxq->free_count += RX_CLAIM_REQ_ALLOC; } -static void iwl_pcie_rx_allocator_work(struct work_struct *data) +void iwl_pcie_rx_allocator_work(struct work_struct *data) { struct iwl_rb_allocator *rba_p = container_of(data, struct iwl_rb_allocator, rx_alloc); @@ -900,10 +900,6 @@ static int _iwl_pcie_rx_init(struct iwl_trans *trans) return err; } def_rxq = trans_pcie->rxq; - if (!rba->alloc_wq) - rba->alloc_wq = alloc_workqueue("rb_allocator", - WQ_HIGHPRI | WQ_UNBOUND, 1); - INIT_WORK(&rba->rx_alloc, iwl_pcie_rx_allocator_work); spin_lock(&rba->lock); atomic_set(&rba->req_pending, 0); @@ -1017,10 +1013,6 @@ void iwl_pcie_rx_free(struct iwl_trans *trans) } cancel_work_sync(&rba->rx_alloc); - if (rba->alloc_wq) { - destroy_workqueue(rba->alloc_wq); - rba->alloc_wq = NULL; - } iwl_pcie_free_rbs_pool(trans); diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c index f95eec52508e..3927bbf04f72 100644 --- a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c +++ b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c @@ -1786,6 +1786,11 @@ void iwl_trans_pcie_free(struct iwl_trans *trans) iwl_pcie_tx_free(trans); iwl_pcie_rx_free(trans); + if (trans_pcie->rba.alloc_wq) { + destroy_workqueue(trans_pcie->rba.alloc_wq); + trans_pcie->rba.alloc_wq = NULL; + } + if (trans_pcie->msix_enabled) { for (i = 0; i < trans_pcie->alloc_vecs; i++) { irq_set_affinity_hint( @@ -3169,6 +3174,10 @@ struct iwl_trans *iwl_trans_pcie_alloc(struct pci_dev *pdev, trans_pcie->inta_mask = CSR_INI_SET_MASK; } + trans_pcie->rba.alloc_wq = alloc_workqueue("rb_allocator", + WQ_HIGHPRI | WQ_UNBOUND, 1); + INIT_WORK(&trans_pcie->rba.rx_alloc, iwl_pcie_rx_allocator_work); + #ifdef CONFIG_IWLWIFI_PCIE_RTPM trans->runtime_pm_mode = IWL_PLAT_PM_MODE_D0I3; #else -- 2.30.2