Hi!
From: Arseniy Krasnov avkrasnov@salutedevices.com
[ Upstream commit 366ceff495f902182d42b6f41525c2474caf3f9a ]
'hci_register_dev()' calls power up function, which is executed by kworker - 'hci_power_on()'. This function does access to bluetooth chip using callbacks from 'hci_ldisc.c', for example 'hci_uart_send_frame()'. Now 'hci_uart_send_frame()' checks 'HCI_UART_PROTO_READY' bit set, and if not - it fails. Problem is that 'HCI_UART_PROTO_READY' is set after 'hci_register_dev()', and there is tiny chance that 'hci_power_on()' will be executed before setting this bit. In that case HCI init logic fails.
Patch moves setting of 'HCI_UART_PROTO_READY' before calling function 'hci_uart_register_dev()'.
Ok, but do we need to adjust the error handling?
+++ b/drivers/bluetooth/hci_ldisc.c @@ -706,12 +706,13 @@ static int hci_uart_set_proto(struct hci_uart *hu, int id) hu->proto = p;
- set_bit(HCI_UART_PROTO_READY, &hu->flags);
- err = hci_uart_register_dev(hu); if (err) { return err; }
- set_bit(HCI_UART_PROTO_READY, &hu->flags); return 0;
}
Should we clear the bit in the error path to undo the effects?
Best regards, Pavel