This patch will fix the below issues 1.Fixed race conditions while accessing memory dump state flags. 2.Updated with actual context of timer in hci_memdump_timeout() 3.Updated injecting hardware error event if the dumps failed to receive. 4.Once timeout is triggered, stopping the memory dump collections. Possible scenarios while collecting memory dump: Scenario 1: Memdump event from firmware Some number of memdump events with seq # Hw error event Reset Scenario 2: Memdump event from firmware Some number of memdump events with seq # Timeout schedules hw_error_event if hw error event is not received already hw_error_event clears the memdump activity reset Scenario 3: hw_error_event sends memdump command to firmware and waits for completion Some number of memdump events with seq # hw error event reset Fixes: d841502c79e3 ("Bluetooth: hci_qca: Collect controller memory dump during SSR") Reported-by: Abhishek Pandit-Subedi <abhishekpandit@xxxxxxxxxxxx> Signed-off-by: Venkata Lakshmi Narayana Gubba <gubbaven@xxxxxxxxxxxxxx> --- v3: * Removed memdump_timer completely. * Used delayed work queue. --- drivers/bluetooth/hci_qca.c | 101 +++++++++++++++++++++++++++++--------------- 1 file changed, 67 insertions(+), 34 deletions(-) diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c index eacc65b..9cae5fe 100644 --- a/drivers/bluetooth/hci_qca.c +++ b/drivers/bluetooth/hci_qca.c @@ -29,6 +29,7 @@ #include <linux/platform_device.h> #include <linux/regulator/consumer.h> #include <linux/serdev.h> +#include <linux/mutex.h> #include <asm/unaligned.h> #include <net/bluetooth/bluetooth.h> @@ -69,7 +70,8 @@ enum qca_flags { QCA_IBS_ENABLED, QCA_DROP_VENDOR_EVENT, QCA_SUSPENDING, - QCA_MEMDUMP_COLLECTION + QCA_MEMDUMP_COLLECTION, + QCA_HW_ERROR_EVENT }; @@ -138,18 +140,19 @@ struct qca_data { u32 tx_idle_delay; struct timer_list wake_retrans_timer; u32 wake_retrans; - struct timer_list memdump_timer; struct workqueue_struct *workqueue; struct work_struct ws_awake_rx; struct work_struct ws_awake_device; struct work_struct ws_rx_vote_off; struct work_struct ws_tx_vote_off; struct work_struct ctrl_memdump_evt; + struct delayed_work ctrl_memdump_timeout; struct qca_memdump_data *qca_memdump; unsigned long flags; struct completion drop_ev_comp; wait_queue_head_t suspend_wait_q; enum qca_memdump_states memdump_state; + struct mutex hci_memdump_lock; /* For debugging purpose */ u64 ibs_sent_wacks; @@ -522,23 +525,28 @@ static void hci_ibs_wake_retrans_timeout(struct timer_list *t) hci_uart_tx_wakeup(hu); } -static void hci_memdump_timeout(struct timer_list *t) + +static void qca_controller_memdump_timeout(struct work_struct *work) { - struct qca_data *qca = from_timer(qca, t, tx_idle_timer); + struct qca_data *qca = container_of(work, struct qca_data, + ctrl_memdump_timeout.work); struct hci_uart *hu = qca->hu; - struct qca_memdump_data *qca_memdump = qca->qca_memdump; - char *memdump_buf = qca_memdump->memdump_buf_tail; - - bt_dev_err(hu->hdev, "clearing allocated memory due to memdump timeout"); - /* Inject hw error event to reset the device and driver. */ - hci_reset_dev(hu->hdev); - vfree(memdump_buf); - kfree(qca_memdump); - qca->memdump_state = QCA_MEMDUMP_TIMEOUT; - del_timer(&qca->memdump_timer); - cancel_work_sync(&qca->ctrl_memdump_evt); + + mutex_lock(&qca->hci_memdump_lock); + if (test_bit(QCA_MEMDUMP_COLLECTION, &qca->flags)) { + qca->memdump_state = QCA_MEMDUMP_TIMEOUT; + if (!test_bit(QCA_HW_ERROR_EVENT, &qca->flags)) { + /* Inject hw error event to reset the device + * and driver. + */ + hci_reset_dev(hu->hdev); + } + } + + mutex_unlock(&qca->hci_memdump_lock); } + /* Initialize protocol */ static int qca_open(struct hci_uart *hu) { @@ -558,6 +566,7 @@ static int qca_open(struct hci_uart *hu) skb_queue_head_init(&qca->tx_wait_q); skb_queue_head_init(&qca->rx_memdump_q); spin_lock_init(&qca->hci_ibs_lock); + mutex_init(&qca->hci_memdump_lock); qca->workqueue = alloc_ordered_workqueue("qca_wq", 0); if (!qca->workqueue) { BT_ERR("QCA Workqueue not initialized properly"); @@ -570,6 +579,8 @@ static int qca_open(struct hci_uart *hu) INIT_WORK(&qca->ws_rx_vote_off, qca_wq_serial_rx_clock_vote_off); INIT_WORK(&qca->ws_tx_vote_off, qca_wq_serial_tx_clock_vote_off); INIT_WORK(&qca->ctrl_memdump_evt, qca_controller_memdump); + INIT_DELAYED_WORK(&qca->ctrl_memdump_timeout, + qca_controller_memdump_timeout); init_waitqueue_head(&qca->suspend_wait_q); qca->hu = hu; @@ -596,7 +607,6 @@ static int qca_open(struct hci_uart *hu) timer_setup(&qca->tx_idle_timer, hci_ibs_tx_idle_timeout, 0); qca->tx_idle_delay = IBS_HOST_TX_IDLE_TIMEOUT_MS; - timer_setup(&qca->memdump_timer, hci_memdump_timeout, 0); BT_DBG("HCI_UART_QCA open, tx_idle_delay=%u, wake_retrans=%u", qca->tx_idle_delay, qca->wake_retrans); @@ -677,7 +687,6 @@ static int qca_close(struct hci_uart *hu) skb_queue_purge(&qca->rx_memdump_q); del_timer(&qca->tx_idle_timer); del_timer(&qca->wake_retrans_timer); - del_timer(&qca->memdump_timer); destroy_workqueue(qca->workqueue); qca->hu = NULL; @@ -963,11 +972,20 @@ static void qca_controller_memdump(struct work_struct *work) while ((skb = skb_dequeue(&qca->rx_memdump_q))) { + mutex_lock(&qca->hci_memdump_lock); + /* Skip processing the received packets if timeout detected. */ + if (qca->memdump_state == QCA_MEMDUMP_TIMEOUT) { + mutex_unlock(&qca->hci_memdump_lock); + return; + } + if (!qca_memdump) { qca_memdump = kzalloc(sizeof(struct qca_memdump_data), GFP_ATOMIC); - if (!qca_memdump) + if (!qca_memdump) { + mutex_unlock(&qca->hci_memdump_lock); return; + } qca->qca_memdump = qca_memdump; } @@ -992,13 +1010,15 @@ static void qca_controller_memdump(struct work_struct *work) if (!(dump_size)) { bt_dev_err(hu->hdev, "Rx invalid memdump size"); kfree_skb(skb); + mutex_unlock(&qca->hci_memdump_lock); return; } bt_dev_info(hu->hdev, "QCA collecting dump of size:%u", dump_size); - mod_timer(&qca->memdump_timer, (jiffies + - msecs_to_jiffies(MEMDUMP_TIMEOUT_MS))); + queue_delayed_work(qca->workqueue, + &qca->ctrl_memdump_timeout, + msecs_to_jiffies(MEMDUMP_TIMEOUT_MS)); skb_pull(skb, sizeof(dump_size)); memdump_buf = vmalloc(dump_size); @@ -1016,6 +1036,7 @@ static void qca_controller_memdump(struct work_struct *work) kfree(qca_memdump); kfree_skb(skb); qca->qca_memdump = NULL; + mutex_unlock(&qca->hci_memdump_lock); return; } @@ -1046,16 +1067,20 @@ static void qca_controller_memdump(struct work_struct *work) memdump_buf = qca_memdump->memdump_buf_head; dev_coredumpv(&hu->serdev->dev, memdump_buf, qca_memdump->received_dump, GFP_KERNEL); - del_timer(&qca->memdump_timer); + cancel_delayed_work(&qca->ctrl_memdump_timeout); kfree(qca->qca_memdump); qca->qca_memdump = NULL; qca->memdump_state = QCA_MEMDUMP_COLLECTED; + clear_bit(QCA_MEMDUMP_COLLECTION, &qca->flags); } + + mutex_unlock(&qca->hci_memdump_lock); } } -int qca_controller_memdump_event(struct hci_dev *hdev, struct sk_buff *skb) +static int qca_controller_memdump_event(struct hci_dev *hdev, + struct sk_buff *skb) { struct hci_uart *hu = hci_get_drvdata(hdev); struct qca_data *qca = hu->priv; @@ -1406,30 +1431,21 @@ static void qca_wait_for_dump_collection(struct hci_dev *hdev) { struct hci_uart *hu = hci_get_drvdata(hdev); struct qca_data *qca = hu->priv; - struct qca_memdump_data *qca_memdump = qca->qca_memdump; - char *memdump_buf = NULL; wait_on_bit_timeout(&qca->flags, QCA_MEMDUMP_COLLECTION, TASK_UNINTERRUPTIBLE, MEMDUMP_TIMEOUT_MS); clear_bit(QCA_MEMDUMP_COLLECTION, &qca->flags); - if (qca->memdump_state == QCA_MEMDUMP_IDLE) { - bt_dev_err(hu->hdev, "Clearing the buffers due to timeout"); - if (qca_memdump) - memdump_buf = qca_memdump->memdump_buf_tail; - vfree(memdump_buf); - kfree(qca_memdump); - qca->memdump_state = QCA_MEMDUMP_TIMEOUT; - del_timer(&qca->memdump_timer); - cancel_work_sync(&qca->ctrl_memdump_evt); - } } static void qca_hw_error(struct hci_dev *hdev, u8 code) { struct hci_uart *hu = hci_get_drvdata(hdev); struct qca_data *qca = hu->priv; + struct qca_memdump_data *qca_memdump = qca->qca_memdump; + char *memdump_buf = NULL; + set_bit(QCA_HW_ERROR_EVENT, &qca->flags); bt_dev_info(hdev, "mem_dump_status: %d", qca->memdump_state); if (qca->memdump_state == QCA_MEMDUMP_IDLE) { @@ -1449,6 +1465,23 @@ static void qca_hw_error(struct hci_dev *hdev, u8 code) bt_dev_info(hdev, "waiting for dump to complete"); qca_wait_for_dump_collection(hdev); } + + if (qca->memdump_state != QCA_MEMDUMP_COLLECTED) { + bt_dev_err(hu->hdev, "clearing allocated memory due to memdump timeout"); + mutex_lock(&qca->hci_memdump_lock); + if (qca_memdump) + memdump_buf = qca_memdump->memdump_buf_head; + vfree(memdump_buf); + kfree(qca_memdump); + qca->qca_memdump = NULL; + qca->memdump_state = QCA_MEMDUMP_TIMEOUT; + cancel_delayed_work(&qca->ctrl_memdump_timeout); + skb_queue_purge(&qca->rx_memdump_q); + mutex_unlock(&qca->hci_memdump_lock); + cancel_work_sync(&qca->ctrl_memdump_evt); + } + + clear_bit(QCA_HW_ERROR_EVENT, &qca->flags); } static void qca_cmd_timeout(struct hci_dev *hdev) -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation