Bluetooth: Avoid race condition between hci registration/un-registration
Syncronized hci device registration/un-registration to avoid race
condition when called from mutiple paths/scenarios concurrently.
CRs-fixed: 375287
Change-Id: I920e7ade5b006b630ad8b02f953883a69b9677c7
Signed-off-by: Bhasker Neti <bneti@codeaurora.org>
diff --git a/drivers/bluetooth/hci_smd.c b/drivers/bluetooth/hci_smd.c
index 66bd739..6030520 100644
--- a/drivers/bluetooth/hci_smd.c
+++ b/drivers/bluetooth/hci_smd.c
@@ -42,6 +42,7 @@
*/
#define RX_Q_MONITOR (500) /* 500 milli second */
+#define HCI_REGISTER_SET 0
static int hcismd_set;
@@ -57,7 +58,7 @@
struct hci_smd_data {
struct hci_dev *hdev;
-
+ unsigned long flags;
struct smd_channel *event_channel;
struct smd_channel *data_channel;
struct wake_lock wake_lock_tx;
@@ -403,11 +404,16 @@
struct hci_dev *hdev;
hdev = hsmd->hdev;
-
+ if (test_and_set_bit(HCI_REGISTER_SET, &hsmd->flags)) {
+ BT_ERR("HCI device registered already");
+ return 0;
+ } else
+ BT_INFO("HCI device registration is starting");
if (hci_register_dev(hdev) < 0) {
BT_ERR("Can't register HCI device");
hci_free_dev(hdev);
hsmd->hdev = NULL;
+ clear_bit(HCI_REGISTER_SET, &hsmd->flags);
return -ENODEV;
}
return 0;
@@ -473,6 +479,11 @@
{
tasklet_kill(&hs.rx_task);
+ if (!test_and_clear_bit(HCI_REGISTER_SET, &hsmd->flags)) {
+ BT_ERR("HCI device un-registered already");
+ return;
+ } else
+ BT_INFO("HCI device un-registration going on");
if (hsmd->hdev) {
if (hci_unregister_dev(hsmd->hdev) < 0)
BT_ERR("Can't unregister HCI device %s",