download_firmware() is never called from atomic context. It is only called by ll_setup() that is called only via function pointer "->setup" used in hci_uart_setup() in drivers/bluetooth/hci_serdev.c and drivers/bluetooth/hci_ldisc.c. hci_uart_setup() is called only via function pointer "->setup" used in hci_dev_do_open() in net/bluetooth/hci_core.c. All of the above functions do not enter atomic context. Besides, ll_setup() calls msleep() and hci_dev_do_open calls mutex_lock(). So it indicates that all the above functions call functions that can sleep. Despite never getting called from atomic context, download_firmware() calls mdelay() for busy wait. That is not necessary and can be replaced with msleep to avoid busy wait. This is found by a static analysis tool named DCNS written by myself. Signed-off-by: Jia-Ju Bai <baijiaju1990@xxxxxxxxx> --- drivers/bluetooth/hci_ll.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/bluetooth/hci_ll.c b/drivers/bluetooth/hci_ll.c index e2c078d..f804adc 100644 --- a/drivers/bluetooth/hci_ll.c +++ b/drivers/bluetooth/hci_ll.c @@ -644,7 +644,7 @@ static int download_firmware(struct ll_device *lldev) break; case ACTION_DELAY: /* sleep */ bt_dev_info(lldev->hu.hdev, "sleep command in scr"); - mdelay(((struct bts_action_delay *)action_ptr)->msec); + msleep(((struct bts_action_delay *)action_ptr)->msec); break; } len -= (sizeof(struct bts_action) + -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
