Messages in this thread Patch in this message | | | Date | Fri, 21 Dec 2007 06:10:15 +1030 | From | David Newall <> | Subject | Re: Kernel bug: bluetooth meets TTY layer |
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Hi Arjan,
I've not been able to find this file, "drivers/bluetooth/hci_tty.c", but anyway, This seems to be what happens: Hci_uart_close() flushes using hci_uart_flush(). Subsequently, in hci_dev_do_close(), (one step in hci_unregister_dev()), hci_uart_flush() is called again. The comment in uart_flush_buffer(), relating to the WARN_ON(), indicates you can't flush after the port is closed; which sounds reasonable. I think hci_uart_close() should set hdev->flush to NULL before returning. Hci_dev_do_close() does check for this. The code path is rather involved and I'm not entirely clear of all steps, but I think that's what should be done.
Patch for stupidly obsolete kernel attached.
David --- hci_ldisc.c 2007-09-11 02:54:02.000000000 +0930 +++ hci_ldisc.c.new 2007-12-21 06:03:11.000000000 +1030 @@ -203,16 +203,17 @@ static int hci_uart_close(struct hci_dev *hdev) { BT_DBG("hdev %p", hdev); if (!test_and_clear_bit(HCI_RUNNING, &hdev->flags)) return 0; hci_uart_flush(hdev); + hdev->flush = NULL; return 0; } /* Send frames from HCI layer */ static int hci_uart_send_frame(struct sk_buff *skb) { struct hci_dev* hdev = (struct hci_dev *) skb->dev; struct tty_struct *tty; | |