From 5d49e68392039ac2e480b4756c175ffd91920ca3 Mon Sep 17 00:00:00 2001 From: Slawomir Laba Date: Wed, 23 Feb 2022 13:37:10 +0100 Subject: [PATCH] iavf: Fix init state closure on remove BugLink: https://bugs.launchpad.net/bugs/1964361 [ Upstream commit 3ccd54ef44ebfa0792c5441b6d9c86618f3378d1 ] When init states of the adapter work, the errors like lack of communication with the PF might hop in. If such events occur the driver restores previous states in order to retry initialization in a proper way. When remove task kicks in, this situation could lead to races with unregistering the netdevice as well as resources cleanup. With the commit introducing the waiting in remove for init to complete, this problem turns into an endless waiting if init never recovers from errors. Introduce __IAVF_IN_REMOVE_TASK bit to indicate that the remove thread has started. Make __IAVF_COMM_FAILED adapter state respect the __IAVF_IN_REMOVE_TASK bit and set the __IAVF_INIT_FAILED state and return without any action instead of trying to recover. Make __IAVF_INIT_FAILED adapter state respect the __IAVF_IN_REMOVE_TASK bit and return without any further actions. Make the loop in the remove handler break when adapter has __IAVF_INIT_FAILED state set. Fixes: 898ef1cb1cb2 ("iavf: Combine init and watchdog state machines") 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 Signed-off-by: Sasha Levin Signed-off-by: Paolo Pisati --- drivers/net/ethernet/intel/iavf/iavf.h | 4 ++++ drivers/net/ethernet/intel/iavf/iavf_main.c | 24 ++++++++++++++++++++- 2 files changed, 27 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/intel/iavf/iavf.h b/drivers/net/ethernet/intel/iavf/iavf.h index 21e0f3361560..ffc61993019b 100644 --- a/drivers/net/ethernet/intel/iavf/iavf.h +++ b/drivers/net/ethernet/intel/iavf/iavf.h @@ -188,6 +188,10 @@ enum iavf_state_t { __IAVF_RUNNING, /* opened, working */ }; +enum iavf_critical_section_t { + __IAVF_IN_REMOVE_TASK, /* device being removed */ +}; + #define IAVF_CLOUD_FIELD_OMAC 0x01 #define IAVF_CLOUD_FIELD_IMAC 0x02 #define IAVF_CLOUD_FIELD_IVLAN 0x04 diff --git a/drivers/net/ethernet/intel/iavf/iavf_main.c b/drivers/net/ethernet/intel/iavf/iavf_main.c index 60e6f55c6dc5..57ecdff870a1 100644 --- a/drivers/net/ethernet/intel/iavf/iavf_main.c +++ b/drivers/net/ethernet/intel/iavf/iavf_main.c @@ -2019,6 +2019,15 @@ static void iavf_watchdog_task(struct work_struct *work) msecs_to_jiffies(1)); return; case __IAVF_INIT_FAILED: + if (test_bit(__IAVF_IN_REMOVE_TASK, + &adapter->crit_section)) { + /* Do not update the state and do not reschedule + * watchdog task, iavf_remove should handle this state + * as it can loop forever + */ + mutex_unlock(&adapter->crit_lock); + return; + } if (++adapter->aq_wait_count > IAVF_AQ_MAX_ERR) { dev_err(&adapter->pdev->dev, "Failed to communicate with PF; waiting before retry\n"); @@ -2035,6 +2044,17 @@ static void iavf_watchdog_task(struct work_struct *work) queue_delayed_work(iavf_wq, &adapter->watchdog_task, HZ); return; case __IAVF_COMM_FAILED: + if (test_bit(__IAVF_IN_REMOVE_TASK, + &adapter->crit_section)) { + /* Set state to __IAVF_INIT_FAILED and perform remove + * steps. Remove IAVF_FLAG_PF_COMMS_FAILED so the task + * doesn't bring the state back to __IAVF_COMM_FAILED. + */ + iavf_change_state(adapter, __IAVF_INIT_FAILED); + adapter->flags &= ~IAVF_FLAG_PF_COMMS_FAILED; + mutex_unlock(&adapter->crit_lock); + return; + } reg_val = rd32(hw, IAVF_VFGEN_RSTAT) & IAVF_VFGEN_RSTAT_VFR_STATE_MASK; if (reg_val == VIRTCHNL_VFR_VFACTIVE || @@ -3988,13 +4008,15 @@ static void iavf_remove(struct pci_dev *pdev) struct iavf_hw *hw = &adapter->hw; int err; + set_bit(__IAVF_IN_REMOVE_TASK, &adapter->crit_section); /* 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) { + adapter->state == __IAVF_DOWN || + adapter->state == __IAVF_INIT_FAILED) { mutex_unlock(&adapter->crit_lock); break; } -- 2.39.5