From 974578017fc1fdd06cea8afb9dfa32602e8529ed Mon Sep 17 00:00:00 2001 From: Slawomir Laba Date: Wed, 23 Feb 2022 13:36:56 +0100 Subject: [PATCH] iavf: Add waiting so the port is initialized in remove There exist races when port is being configured and remove is triggered. unregister_netdev is not and can't be called under crit_lock mutex since it is calling ndo_stop -> iavf_close which requires this lock. Depending on init state the netdev could be still unregistered so unregister_netdev never cleans up, when shortly after that the device could become registered. Make iavf_remove wait until port finishes initialization. All critical state changes are atomic (under crit_lock). Crashes that come from iavf_reset_interrupt_capability and iavf_free_traffic_irqs should now be solved in a graceful manner. Fixes: 605ca7c5c6707 ("iavf: Fix kernel BUG in free_msi_irqs") Signed-off-by: Slawomir Laba Signed-off-by: Phani Burra Signed-off-by: Jacob Keller Signed-off-by: Mateusz Palczewski Tested-by: Konrad Jankowski Signed-off-by: Tony Nguyen --- drivers/net/ethernet/intel/iavf/iavf_main.c | 27 ++++++++++++--------- 1 file changed, 16 insertions(+), 11 deletions(-) diff --git a/drivers/net/ethernet/intel/iavf/iavf_main.c b/drivers/net/ethernet/intel/iavf/iavf_main.c index 84ae96e912d793..5e71b38e9154d6 100644 --- a/drivers/net/ethernet/intel/iavf/iavf_main.c +++ b/drivers/net/ethernet/intel/iavf/iavf_main.c @@ -4558,7 +4558,6 @@ 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; @@ -4568,6 +4567,22 @@ static void iavf_remove(struct pci_dev *pdev) struct iavf_hw *hw = &adapter->hw; int err; + /* 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) { + mutex_unlock(&adapter->crit_lock); + break; + } + + mutex_unlock(&adapter->crit_lock); + usleep_range(500, 1000); + } + cancel_delayed_work_sync(&adapter->watchdog_task); + if (adapter->netdev_registered) { unregister_netdev(netdev); adapter->netdev_registered = false; @@ -4605,16 +4620,6 @@ static void iavf_remove(struct pci_dev *pdev) iavf_free_all_rx_resources(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);