Hi,
We found this issue in Chromebook with kernel 3.14. From btmon, Stack received event of Remote Name Req Complete with Device name "Name: VGP-BMS21", but it's after @ Discovering: 0x00 (7). It means le_scan_disable_work_complete set discover status to STOPPED for starting new discovery which caused hci_check_pending_name return without update the name information because discovery status is STOPPED. Then user space will always get null name, even hci_remote_name_evt shows everything is correct at HCI layer.
Is it possible setting LE Set Scan Enable to disable after Remote Name Req Complete? Or adding condition for hci_discovery_set_state(hdev, DISCOVERY_STOPPED) in function of le_scan_disable_work_complete?
static void le_scan_disable_work_complete(struct hci_dev *hdev, u8 status,
u16 opcode)
{
/* General inquiry access code (GIAC) */
.....
.......
case DISCOV_TYPE_INTERLEAVED:
hci_dev_lock(hdev);
if (test_bit(HCI_QUIRK_SIMULTANEOUS_DISCOVERY,
&hdev->quirks)) {
/* If we were running LE only scan, change discovery
* state. If we were running both LE and BR/EDR inquiry
* simultaneously, and BR/EDR inquiry is already
* finished, stop discovery, otherwise BR/EDR inquiry
* will stop discovery when finished.
*/
if (!test_bit(HCI_INQUIRY, &hdev->flags))
hci_discovery_set_state(hdev, /* <------------- Here set set discover status to STOPPED */
DISCOVERY_STOPPED);
static void hci_check_pending_name(struct hci_dev *hdev, struct hci_conn *conn,
bdaddr_t *bdaddr, u8 *name, u8 name_len)
{
struct discovery_state *discov = &hdev->discovery;
struct inquiry_entry *e;
/* Update the mgmt connected state if necessary. Be careful with
* conn objects that exist but are not (yet) connected however.
* Only those in BT_CONFIG or BT_CONNECTED states can be
* considered connected.
*/
if (conn &&
(conn->state == BT_CONFIG || conn->state == BT_CONNECTED) &&
!test_and_set_bit(HCI_CONN_MGMT_CONNECTED, &conn->flags))
mgmt_device_connected(hdev, conn, 0, name, name_len);
if (discov->state == DISCOVERY_STOPPED) /* <------------- Return due to (discov->state == DISCOVERY_STOPPED) */
return;
btmon:
@ Discovering: 0x01 (7)
...
....
> HCI Event: Inquiry Complete (0x01) plen 1 [hci0] 39.027238
Status: Success (0x00)
< HCI Command: Remote Name Request (0x01|0x0019) plen 10 [hci0] 39.027342
Address: 90:7F:61:0F:24:41 (OUI 90-7F-61)
Page scan repetition mode: R1 (0x01)
Page scan mode: Mandatory (0x00)
Clock offset: 0x7774
> HCI Event: Command Status (0x0f) plen 4 [hci0] 39.028072
Remote Name Request (0x01|0x0019) ncmd 1
Status: Success (0x00)
< HCI Command: LE Set Scan Enable (0x08|0x000c) plen 2 [hci0] 39.060051
Scanning: Disabled (0x00)
Filter duplicates: Disabled (0x00)
> HCI Event: Command Complete (0x0e) plen 4 [hci0] 39.062071
LE Set Scan Enable (0x08|0x000c) ncmd 2
Status: Success (0x00)
@ Discovering: 0x00 (7)
> HCI Event: Remote Host Supported Features (0x3d) plen 14 [hci0] 39.536284
Address: 90:7F:61:0F:24:41 (OUI 90-7F-61)
Features: 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
> HCI Event: Remote Name Req Complete (0x07) plen 255 [hci0] 39.628124
Status: Success (0x00)
Address: 90:7F:61:0F:24:41 (OUI 90-7F-61)
Name: VGP-BMS21
< HCI Command: LE Set Random Address (0x08|0x0005) plen 6 [hci0] 44.786231
Address: 24:AF:E7:B5:2D:00 (Non-Resolvable)
> HCI Event: Command Complete (0x0e) plen 4 [hci0] 44.946206
LE Set Random Address (0x08|0x0005) ncmd 1
Status: Success (0x00)
< HCI Command: LE Set Scan Parameters (0x08|0x000b) plen 7 [hci0] 44.946270
Type: Active (0x01)
Interval: 22.500 msec (0x0024)
Window: 11.250 msec (0x0012)
Own address type: Random (0x01)
Filter policy: Accept all advertisement (0x00)
> HCI Event: Command Complete (0x0e) plen 4 [hci0] 44.947201
LE Set Scan Parameters (0x08|0x000b) ncmd 1
Status: Success (0x00)
< HCI Command: LE Set Scan Enable (0x08|0x000c) plen 2 [hci0] 44.947296
Scanning: Enabled (0x01)
Filter duplicates: Enabled (0x01)
> HCI Event: Command Complete (0x0e) plen 4 [hci0] 44.948203
LE Set Scan Enable (0x08|0x000c) ncmd 2
Status: Success (0x00)
< HCI Command: Inquiry (0x01|0x0001) plen 5 [hci0] 44.948266
Access code: 0x9e8b33 (General Inquiry)
Length: 10.24s (0x08)
Num responses: 0
> HCI Event: Command Status (0x0f) plen 4 [hci0] 44.949207
Inquiry (0x01|0x0001) ncmd 2
Status: Success (0x00)
Regards,
Ethan
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