| Message ID | 20210315173059.74030-1-sonnysasaka@chromium.org |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] Bluetooth: Cancel le_scan_restart work when stopping discovery | expand |
diff --git a/net/bluetooth/hci_request.c b/net/bluetooth/hci_request.c index d7ee11ef70d3e..8ace5d34b01ef 100644 --- a/net/bluetooth/hci_request.c +++ b/net/bluetooth/hci_request.c @@ -3252,6 +3252,7 @@ bool hci_req_stop_discovery(struct hci_request *req) if (hci_dev_test_flag(hdev, HCI_LE_SCAN)) { cancel_delayed_work(&hdev->le_scan_disable); + cancel_delayed_work(&hdev->le_scan_restart); hci_req_add_le_scan_disable(req, false); }
Not cancelling it has caused a bug where passive background scanning is disabled out of the blue, preventing BLE keyboards/mice to reconnect. Here is how it happens: After hci_req_stop_discovery, there is still le_scan_restart_work scheduled. Invocation of le_scan_restart_work causes a harmful le_scan_disable_work to be scheduled. This le_scan_disable_work will eventually disable passive scanning when the timer fires. Sample btmon trace: < HCI Command: LE Set Scan Parameters (0x08|0x000b) plen 7 Type: Passive (0x00) Interval: 367.500 msec (0x024c) Window: 37.500 msec (0x003c) Own address type: Public (0x00) Filter policy: Accept all advertisement (0x00) > HCI Event: Command Complete (0x0e) plen 4 LE Set Scan Parameters (0x08|0x000b) ncmd 1 Status: Success (0x00) < HCI Command: LE Set Scan Enable (0x08|0x000c) plen 2 Scanning: Enabled (0x01) Filter duplicates: Disabled (0x00) > HCI Event: Command Complete (0x0e) plen 4 LE Set Scan Enable (0x08|0x000c) ncmd 2 Status: Success (0x00) ... < HCI Command: LE Set Scan Enable (0x08|0x000c) plen 2 Scanning: Disabled (0x00) Filter duplicates: Disabled (0x00) > HCI Event: Command Complete (0x0e) plen 4 LE Set Scan Enable (0x08|0x000c) ncmd 2 Status: Success (0x00) // Background scanning is not working here onwards. Reviewed-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org> Signed-off-by: Sonny Sasaka <sonnysasaka@chromium.org> --- net/bluetooth/hci_request.c | 1 + 1 file changed, 1 insertion(+)