Re: possible recursive locking in 2.6.30-rc6

Oliver Hartkopp
2009-05-25T19:55:28Z

Oliver Hartkopp wrote:
> Hi all,
>

This is another trace after having a successful connection and after
terminating this connection after 40 secs with the latest 2.6.30-rc7.

When the kernel config is needed please give me a note.

Tnx,
Oliver

[ 52.331965] PPP generic driver version 2.4.2
[ 57.917179] PPP BSD Compression module registered
[ 57.964543] PPP Deflate Compression module registered
[ 97.634897]
[ 97.634901] =============================================
[ 97.638773] [ INFO: possible recursive locking detected ]
[ 97.638773] 2.6.30-rc7 #23
[ 97.638773] ---------------------------------------------
[ 97.638773] bluetooth/2505 is trying to acquire lock:
[ 97.669944] (bluetooth){+.+.+.}, at: [<c0130c14>] flush_work+0x28/0xb0
[ 97.669944]
[ 97.669944] but task is already holding lock:
[ 97.669944] (bluetooth){+.+.+.}, at: [<c0130424>] worker_thread+0x149/0x25e
[ 97.669944]
[ 97.669944] other info that might help us debug this:
[ 97.669944] 2 locks held by bluetooth/2505:
[ 97.669944] #0: (bluetooth){+.+.+.}, at: [<c0130424>]
worker_thread+0x149/0x25e
[ 97.669944] #1: (&conn->work_del){+.+...}, at: [<c0130424>]
worker_thread+0x149/0x25e
[ 97.669944]
[ 97.669944] stack backtrace:
[ 97.669944] Pid: 2505, comm: bluetooth Not tainted 2.6.30-rc7 #23
[ 97.669944] Call Trace:
[ 97.669944] [<c03d5ab1>] ? printk+0xf/0x11
[ 97.669944] [<c0140d9a>] __lock_acquire+0x7ce/0xb1b
[ 97.669944] [<c0141177>] lock_acquire+0x90/0xad
[ 97.669944] [<c0130c14>] ? flush_work+0x28/0xb0
[ 97.669944] [<c0130c2e>] flush_work+0x42/0xb0
[ 97.669944] [<c0130c14>] ? flush_work+0x28/0xb0
[ 97.669944] [<f87f8966>] del_conn+0x1c/0x84 [bluetooth]
[ 97.669944] [<c0130469>] worker_thread+0x18e/0x25e
[ 97.669944] [<c0130424>] ? worker_thread+0x149/0x25e
[ 97.669944] [<f87f894a>] ? del_conn+0x0/0x84 [bluetooth]
[ 97.669944] [<c0133843>] ? autoremove_wake_function+0x0/0x33
[ 97.669944] [<c01302db>] ? worker_thread+0x0/0x25e
[ 97.669944] [<c013355a>] kthread+0x45/0x6b
[ 97.669944] [<c0133515>] ? kthread+0x0/0x6b
[ 97.669944] [<c01034a7>] kernel_thread_helper+0x7/0x10

> i'm sometimes working with BT DUN with a Nokia 6210 Navigator.
>
> Last weekend anything must gone wrong, so my mobile was not able to create a
> ppp link with DUN this morning. After updating the driver and BT-chip firmware
> of my Dell 830 laptop and several pairing attempts i was able to kick it to
> work again ... :-]
>
> And i needed to move the channel from '5' to '3' in /etc/bluetooth/rfcomm.conf
> - i assume the Nokia Windows Software re-configured this in the process of
> re-installing their SW when updating the Windows drivers ... don't know.
>
> In the meantime (when the paring or anything else was broken) i discovered
> this kernel message about a locking issue.
>
> Is this a known problem?
>
> Regards,
> Oliver
>
> ps. Please CC me as i did not subcribe the list. Tnx
>
> =============================================
> [ INFO: possible recursive locking detected ]
> 2.6.30-rc6-02911-gbb803cf #16
> ---------------------------------------------
> bluetooth/2518 is trying to acquire lock:
> (bluetooth){+.+.+.}, at: [<c0130c14>] flush_work+0x28/0xb0
>
> but task is already holding lock:
> (bluetooth){+.+.+.}, at: [<c0130424>] worker_thread+0x149/0x25e
>
> other info that might help us debug this:
> 2 locks held by bluetooth/2518:
> #0: (bluetooth){+.+.+.}, at: [<c0130424>] worker_thread+0x149/0x25e
> #1: (&conn->work_del){+.+...}, at: [<c0130424>] worker_thread+0x149/0x25e
>
> stack backtrace:
> Pid: 2518, comm: bluetooth Not tainted 2.6.30-rc6-02911-gbb803cf #16
> Call Trace:
> [<c03d64d9>] ? printk+0xf/0x11
> [<c0140d96>] __lock_acquire+0x7ce/0xb1b
> [<c0141173>] lock_acquire+0x90/0xad
> [<c0130c14>] ? flush_work+0x28/0xb0
> [<c0130c2e>] flush_work+0x42/0xb0
> [<c0130c14>] ? flush_work+0x28/0xb0
> [<f8b84966>] del_conn+0x1c/0x84 [bluetooth]
> [<c0130469>] worker_thread+0x18e/0x25e
> [<c0130424>] ? worker_thread+0x149/0x25e
> [<f8b8494a>] ? del_conn+0x0/0x84 [bluetooth]
> [<c0133843>] ? autoremove_wake_function+0x0/0x33
> [<c01302db>] ? worker_thread+0x0/0x25e
> [<c013355a>] kthread+0x45/0x6b
> [<c0133515>] ? kthread+0x0/0x6b
> [<c01034a7>] kernel_thread_helper+0x7/0x10
>