diff options
| author | John Keeping <john@metanate.com> | 2018-04-19 17:29:37 +0200 |
|---|---|---|
| committer | Marcel Holtmann <marcel@holtmann.org> | 2018-05-18 06:37:51 +0200 |
| commit | 67d8cee432f5564bba3fe9e0d8b1f07c3e41dda2 (patch) | |
| tree | 5e9713807bf76fcc72ff48be5144f81edab6b365 /net | |
| parent | Bluetooth: Prevent buffer overflow for large advertisement data (diff) | |
| download | linux-67d8cee432f5564bba3fe9e0d8b1f07c3e41dda2.tar.xz linux-67d8cee432f5564bba3fe9e0d8b1f07c3e41dda2.zip | |
Bluetooth: use wait_event API instead of open-coding it
I've seen timeout errors from HCI commands where it looks like
schedule_timeout() has returned immediately; additional logging for the
error case gives:
req_status=1 req_result=0 remaining=10000 jiffies
so the device is still in state HCI_REQ_PEND and the value returned by
schedule_timeout() is the same as the original timeout (HCI_INIT_TIMEOUT
on a system with HZ=1000).
Use wait_event_interruptible_timeout() instead of open-coding similar
behaviour which is subject to the spurious failure described above.
Signed-off-by: John Keeping <john@metanate.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/bluetooth/hci_request.c | 30 |
1 files changed, 7 insertions, 23 deletions
diff --git a/net/bluetooth/hci_request.c b/net/bluetooth/hci_request.c index 66c0781773df..e44d34734834 100644 --- a/net/bluetooth/hci_request.c +++ b/net/bluetooth/hci_request.c @@ -122,7 +122,6 @@ void hci_req_sync_cancel(struct hci_dev *hdev, int err) struct sk_buff *__hci_cmd_sync_ev(struct hci_dev *hdev, u16 opcode, u32 plen, const void *param, u8 event, u32 timeout) { - DECLARE_WAITQUEUE(wait, current); struct hci_request req; struct sk_buff *skb; int err = 0; @@ -135,21 +134,14 @@ struct sk_buff *__hci_cmd_sync_ev(struct hci_dev *hdev, u16 opcode, u32 plen, hdev->req_status = HCI_REQ_PEND; - add_wait_queue(&hdev->req_wait_q, &wait); - set_current_state(TASK_INTERRUPTIBLE); - err = hci_req_run_skb(&req, hci_req_sync_complete); - if (err < 0) { - remove_wait_queue(&hdev->req_wait_q, &wait); - set_current_state(TASK_RUNNING); + if (err < 0) return ERR_PTR(err); - } - schedule_timeout(timeout); + err = wait_event_interruptible_timeout(hdev->req_wait_q, + hdev->req_status != HCI_REQ_PEND, timeout); - remove_wait_queue(&hdev->req_wait_q, &wait); - - if (signal_pending(current)) + if (err == -ERESTARTSYS) return ERR_PTR(-EINTR); switch (hdev->req_status) { @@ -197,7 +189,6 @@ int __hci_req_sync(struct hci_dev *hdev, int (*func)(struct hci_request *req, unsigned long opt, u32 timeout, u8 *hci_status) { struct hci_request req; - DECLARE_WAITQUEUE(wait, current); int err = 0; BT_DBG("%s start", hdev->name); @@ -213,16 +204,10 @@ int __hci_req_sync(struct hci_dev *hdev, int (*func)(struct hci_request *req, return err; } - add_wait_queue(&hdev->req_wait_q, &wait); - set_current_state(TASK_INTERRUPTIBLE); - err = hci_req_run_skb(&req, hci_req_sync_complete); if (err < 0) { hdev->req_status = 0; - remove_wait_queue(&hdev->req_wait_q, &wait); - set_current_state(TASK_RUNNING); - /* ENODATA means the HCI request command queue is empty. * This can happen when a request with conditionals doesn't * trigger any commands to be sent. This is normal behavior @@ -240,11 +225,10 @@ int __hci_req_sync(struct hci_dev *hdev, int (*func)(struct hci_request *req, return err; } - schedule_timeout(timeout); - - remove_wait_queue(&hdev->req_wait_q, &wait); + err = wait_event_interruptible_timeout(hdev->req_wait_q, + hdev->req_status != HCI_REQ_PEND, timeout); - if (signal_pending(current)) + if (err == -ERESTARTSYS) return -EINTR; switch (hdev->req_status) { |