forked from Minki/linux
53e21fbc28
In certain circumstances, such as an HCI driver using __hci_cmd_sync_ev with HCI_EV_CMD_COMPLETE as the expected completion event there is the chance that hci_event_packet will call hci_req_cmd_complete twice (once for the explicitly looked after event and another time in the actual handler of cmd_complete). In the case of __hci_cmd_sync_ev this introduces a race where the first call wakes up the blocking __hci_cmd_sync_ev and lets it complete. However, by the time that a second __hci_cmd_sync_ev call is already in progress the second hci_req_cmd_complete call (from the previous operation) will wake up the blocking function prematurely and cause it to fail, as witnessed by the following log: [ 639.232195] hci_rx_work: hci0 Event packet [ 639.232201] hci_req_cmd_complete: opcode 0xfc8e status 0x00 [ 639.232205] hci_sent_cmd_data: hci0 opcode 0xfc8e [ 639.232210] hci_req_sync_complete: hci0 result 0x00 [ 639.232220] hci_cmd_complete_evt: hci0 opcode 0xfc8e [ 639.232225] hci_req_cmd_complete: opcode 0xfc8e status 0x00 [ 639.232228] __hci_cmd_sync_ev: hci0 end: err 0 [ 639.232234] __hci_cmd_sync_ev: hci0 [ 639.232238] hci_req_add_ev: hci0 opcode 0xfc8e plen 250 [ 639.232242] hci_prepare_cmd: skb len 253 [ 639.232246] hci_req_run: length 1 [ 639.232250] hci_sent_cmd_data: hci0 opcode 0xfc8e [ 639.232255] hci_req_sync_complete: hci0 result 0x00 [ 639.232266] hci_cmd_work: hci0 cmd_cnt 1 cmd queued 1 [ 639.232271] __hci_cmd_sync_ev: hci0 end: err 0 [ 639.232276] Bluetooth: hci0 sending Intel patch command (0xfc8e) failed (-61) Signed-off-by: Johan Hedberg <johan.hedberg@intel.com> Acked-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk> |
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| .. | ||
| bnep | ||
| cmtp | ||
| hidp | ||
| rfcomm | ||
| a2mp.c | ||
| af_bluetooth.c | ||
| amp.c | ||
| hci_conn.c | ||
| hci_core.c | ||
| hci_event.c | ||
| hci_sock.c | ||
| hci_sysfs.c | ||
| Kconfig | ||
| l2cap_core.c | ||
| l2cap_sock.c | ||
| lib.c | ||
| Makefile | ||
| mgmt.c | ||
| sco.c | ||
| smp.c | ||