When Bluetooth controller encounters a coredump, it triggers the Subsystem Restart (SSR) mechanism. The controller first reports the coredump data, and once the data upload is complete, it sends a hw_error event. The host relies on this event to proceed with subsequent recovery actions.

If the host has not finished processing the coredump data when the hw_error event is received, it sets a timer to wait until either the data processing is complete or the timeout expires before handling the event.

The current implementation lacks a wakeup trigger. As a result, even if the coredump data has already been processed, the host continues to wait until the timer expires, causing unnecessary delays in handling the hw_error event.

To fix this issue, adds a `wake_up_bit()` call after the host finishes processing the coredump data. This ensures that the waiting thread is promptly notified and can proceed to handle the hw_error event without waiting for the timeout.

Test case: - Trigger controller coredump using the command: `hcitool cmd 0x3f 0c 26`. - Use `btmon` to capture HCI logs. - Observe the time interval between receiving the hw_error event and the execution of the power-off sequence in the HCI log.

Signed-off-by: Shuai Zhang quic_shuaz@quicinc.com --- drivers/bluetooth/hci_qca.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c index 888176b0f..fa6be1992 100644 --- a/drivers/bluetooth/hci_qca.c +++ b/drivers/bluetooth/hci_qca.c @@ -1103,7 +1103,7 @@ static void qca_controller_memdump(struct work_struct *work) qca->qca_memdump = NULL; qca->memdump_state = QCA_MEMDUMP_COLLECTED; cancel_delayed_work(&qca->ctrl_memdump_timeout); - clear_bit(QCA_MEMDUMP_COLLECTION, &qca->flags); + clear_and_wake_up_bit(QCA_MEMDUMP_COLLECTION, &qca->flags); clear_bit(QCA_IBS_DISABLED, &qca->flags); mutex_unlock(&qca->hci_memdump_lock); return; @@ -1181,7 +1181,7 @@ static void qca_controller_memdump(struct work_struct *work) kfree(qca->qca_memdump); qca->qca_memdump = NULL; qca->memdump_state = QCA_MEMDUMP_COLLECTED; - clear_bit(QCA_MEMDUMP_COLLECTION, &qca->flags); + clear_and_wake_up_bit(QCA_MEMDUMP_COLLECTION, &qca->flags); }

mutex_unlock(&qca->hci_memdump_lock);

Since the timer uses jiffies as its unit rather than ms, the timeout value must be converted from ms to jiffies when configuring the timer. Otherwise, the intended 8s timeout is incorrectly set to approximately 33s.

Cc: stable@vger.kernel.org Fixes: d841502c79e3 ("Bluetooth: hci_qca: Collect controller memory dump during SSR") Signed-off-by: Shuai Zhang quic_shuaz@quicinc.com --- drivers/bluetooth/hci_qca.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c index fa6be1992..c14b2fa9d 100644 --- a/drivers/bluetooth/hci_qca.c +++ b/drivers/bluetooth/hci_qca.c @@ -1602,7 +1602,7 @@ static void qca_wait_for_dump_collection(struct hci_dev *hdev) struct qca_data *qca = hu->priv;

wait_on_bit_timeout(&qca->flags, QCA_MEMDUMP_COLLECTION, - TASK_UNINTERRUPTIBLE, MEMDUMP_TIMEOUT_MS); + TASK_UNINTERRUPTIBLE, msecs_to_jiffies(MEMDUMP_TIMEOUT_MS));

clear_bit(QCA_MEMDUMP_COLLECTION, &qca->flags); }