Pending I-Frame(s) are considered as acknowledgement. To void double
acking (via I-Frame and later via RR) clear ack timer when sending
first pending I-Frame.
Signed-off-by: NSzymon Janc <szymon.janc@tieto.com>
Signed-off-by: NLuiz Augusto von Dentz <luiz.von.dentz@intel.com>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

Make l2cap_ertm_send return number of pending I-Frames transmitted
instead of all (pending + retransmitted) I-Frames transmitted.

As only pending I-Frames are considered as acknowledgement, this could
lead to situation when no ACK was sent in __l2cap_send_ack (if only
already transmitted I-Frames were retransmitted).
Signed-off-by: NSzymon Janc <szymon.janc@tieto.com>
Signed-off-by: NLuiz Augusto von Dentz <luiz.von.dentz@intel.com>
Acked-by: NGustavo F. Padovan <padovan@profusion.mobi>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

In debug use chan %p instead of sk.
Signed-off-by: NAndrei Emeltchenko <andrei.emeltchenko@intel.com>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

Change elseif to switch. This make sense even more with following
patches which otherwise have to add more elseifs statements.
Signed-off-by: NAndrei Emeltchenko <andrei.emeltchenko@intel.com>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

Change is needed to remove dependency on sk when possible
before introducing l2cap channel lock.
Signed-off-by: NAndrei Emeltchenko <andrei.emeltchenko@intel.com>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

This is helpful for device discovery implementation & debuging.
Signed-off-by: NAndre Guedes <andre.guedes@openbossa.org>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

The correct length of the event is the size of the ev struct (not size
of the pointer like the code was previously using) plus the length of
the variable-sized EIR data at the end of the struct.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>

This patch fixes a #define indentation in mgmt.c.
Signed-off-by: NAndre Guedes <andre.guedes@openbossa.org>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

This patch adds LE-Only discovery procedure support to MGMT Start
Discovery command.
Signed-off-by: NAndre Guedes <andre.guedes@openbossa.org>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

We are not supposed to block in start_discovery() because
start_discovery code is running in write() syscall context
and this would block the write operation on the mgmt socket.
This way, we cannot directly call hci_do_le_scan() to scan
LE devices in start_discovery(). To overcome this issue a
derefered work (hdev->le_scan) was created so we can properly
call hci_do_le_scan().

The helper function hci_le_scan() simply set LE scan parameters
and queue hdev->le_scan work. The work is queued on system_long_wq
since it can sleep for a few seconds in the worst case (timeout).
Signed-off-by: NAndre Guedes <andre.guedes@openbossa.org>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

This patch adds to hci_core the hci_do_le_scan function which
should be used to scan LE devices.

In order to enable LE scan, hci_do_le_scan() sends commands (Set
LE Scan Parameters and Set LE Scan Enable) to the controller and
waits for its results. If commands were executed successfully a
delayed work is scheduled to disable the ongoing scanning after
some amount of time. This function blocks.
Signed-off-by: NAndre Guedes <andre.guedes@openbossa.org>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

This patch does a trivial code refacting in hci_discovery_active.
Signed-off-by: NAndre Guedes <andre.guedes@openbossa.org>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

Send MGMT Discovering events once LE scan starts/stops so the
userspace can track when local adapters are discovering LE devices.

This way, we also keep the same behavior of inquiry which sends MGMT
Discovering events once inquiry starts/stops even if it is triggered
by an external tool (e.g. hcitool).
Signed-off-by: NAndre Guedes <andre.guedes@openbossa.org>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

We should only perform a reset in hci_dev_do_close if the
HCI_QUIRK_NO_RESET flag is set (since in such a case a reset will not be
performed when initializing the device).
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>

Use __check_timout helper to remove duplicated code
Signed-off-by: NAndrei Emeltchenko <andrei.emeltchenko@intel.com>
Reviewed-by: NUlisses Furquim <ulisses@profusion.mobi>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

Split HCI scheduling for block and packet flow control.
Signed-off-by: NAndrei Emeltchenko <andrei.emeltchenko@intel.com>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

If we want to have proper pairing support over LE we need to
inform userspace that a new LTK is available, so userspace
can store that key permanently.
Signed-off-by: NVinicius Costa Gomes <vinicius.gomes@openbossa.org>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

With the use of the new structures and lists for the SMP LTK's
we may remove some code that is now unused. No need to have extra
fields of information inside link_key now that it is only used
for Link Keys.
Signed-off-by: NVinicius Costa Gomes <vinicius.gomes@openbossa.org>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

Instead of having a separated command for removing SMP keys, we use the
Remove Keys command to remove *all* keys.
Signed-off-by: NVinicius Costa Gomes <vinicius.gomes@openbossa.org>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

This adds a method to notify that a new LTK is available and
a handler to store keys coming from userspace into the kernel LTK
list.
Signed-off-by: NVinicius Costa Gomes <vinicius.gomes@openbossa.org>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

This updates all the users of the older way, that was using the
link_keys list to store the SMP keys, to use the new way.

This includes defining new types for the keys, we have a type for each
combination of STK/LTK and Master/Slave.
Signed-off-by: NVinicius Costa Gomes <vinicius.gomes@openbossa.org>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

This includes a new list for storing the keys and a new structure used
to represent each key.

Some notes: authenticated is used to identify that the key may be used
to setup a HIGH security link. As the same list is used to store both
the STK's and the LTK's the type field is used so we can separate
between those two types of keys and if the key should be used when
in the master or slave role.
Signed-off-by: NVinicius Costa Gomes <vinicius.gomes@openbossa.org>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

Every command handler of mgmt does a cast to the command structure
so it can properly interpreted. So we can avoid that cast if we
make those functions receive a void * directly.
Signed-off-by: NVinicius Costa Gomes <vinicius.gomes@openbossa.org>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

T: Bus=01 Lev=02 Prnt=02 Port=03 Cnt=03 Dev#= 5 Spd=12 MxCh= 0
D: Ver= 2.00 Cls=ff(vend.) Sub=01 Prot=01 MxPS=64 #Cfgs= 1
P: Vendor=0a5c ProdID=21f3 Rev=01.12
S: Manufacturer=Broadcom Corp
S: Product=BCM20702A0
S: SerialNumber=74DE2B344A7B
C: #Ifs= 4 Cfg#= 1 Atr=e0 MxPwr=0mA
I: If#= 0 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=01 Prot=01 Driver=(none)
I: If#= 1 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=01 Prot=01 Driver=(none)
I: If#= 2 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=(none)
I: If#= 3 Alt= 0 #EPs= 0 Cls=fe(app. ) Sub=01 Prot=01 Driver=(none)
Signed-off-by: NManoj Iyer <manoj.iyer@canonical.com>
Tested-by: NDennis Chua <dennis.chua@canonical.com>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

Fixes possible bug when deleting element from the list in
function hci_chan_list_flush. list_for_each_entry_rcu is used
and after deleting element from the list we also free pointer
and then list_entry_rcu is taken from freed pointer.
Signed-off-by: NAndrei Emeltchenko <andrei.emeltchenko@intel.com>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

Use list_for_each_entry_safe which is safe version against removal
of list entry. Otherwise we remove hci_conn element and reference
next element which result in accessing LIST_POISON.

[   95.571834] Bluetooth: unknown link type 127
[   95.578349] BUG: unable to handle kernel paging request at 20002000
[   95.580236] IP: [<20002000>] 0x20001fff
[   95.580763] *pde = 00000000
[   95.581196] Oops: 0000 [#1] SMP
...
[   95.582298] Pid: 3355, comm: hciconfig Tainted: G   O 3.2.0-VirttualBox
[   95.582298] EIP: 0060:[<20002000>] EFLAGS: 00210206 CPU: 0
[   95.582298] EIP is at 0x20002000
...
[   95.582298] Call Trace:
[   95.582298]  [<f8231ab6>] ? hci_conn_hash_flush+0x76/0xf0 [bluetooth]
[   95.582298]  [<f822bcb1>] hci_dev_do_close+0xc1/0x2e0 [bluetooth]
[   95.582298]  [<f822d679>] ? hci_dev_get+0x69/0xb0 [bluetooth]
[   95.582298]  [<f822e1da>] hci_dev_close+0x2a/0x50 [bluetooth]
[   95.582298]  [<f824102f>] hci_sock_ioctl+0x1af/0x3f0 [bluetooth]
[   95.582298]  [<c11153ea>] ? handle_pte_fault+0x8a/0x8f0
[   95.582298]  [<c146becf>] sock_ioctl+0x5f/0x260
[   95.582298]  [<c146be70>] ? sock_fasync+0x90/0x90
[   95.582298]  [<c1152b33>] do_vfs_ioctl+0x83/0x5b0
[   95.582298]  [<c1563f87>] ? do_page_fault+0x297/0x500
[   95.582298]  [<c1563cf0>] ? spurious_fault+0xd0/0xd0
[   95.582298]  [<c107165b>] ? up_read+0x1b/0x30
[   95.582298]  [<c1563f87>] ? do_page_fault+0x297/0x500
[   95.582298]  [<c100aa9f>] ? init_fpu+0xef/0x160
[   95.582298]  [<c15617c0>] ? do_debug+0x180/0x180
[   95.582298]  [<c100a958>] ? fpu_finit+0x28/0x80
[   95.582298]  [<c11530e7>] sys_ioctl+0x87/0x90
[   95.582298]  [<c156795f>] sysenter_do_call+0x12/0x38
...
Signed-off-by: NAndrei Emeltchenko <andrei.emeltchenko@intel.com>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

This patch implements the Cancel Pair Device command for mgmt. It's used
by user space to cancel an ongoing pairing attempt which was triggered
by the Pair Device command.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>

This patch fixes clearing of HCI_LINK_KEYS and HCI_DEBUG_KEYS
dev_flags while resetting. Without this patch pairing does
not work over management interface for BR-EDR devices.
Signed-off-by: NHemant Gupta <hemant.gupta@stericsson.com>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

This patch sends correct IO Capability response to remote device
in case Local Device supports KeyBoardDisplay IO Capability as
this capability is not valid as per BT spec for IO capability
Request Reply Command.
This capability is mapped to DisplayYesNo which is in accordance
with BT spec.
Signed-off-by: NHemant Gupta <hemant.gupta@stericsson.com>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

Commit 33060542 fixed l2cap conn establishment for non-ssp remote
devices by not setting HCI_CONN_ENCRYPT_PEND every time conn security
is tested (which was always returning failure on any subsequent
security checks).

However, this broke l2cap conn establishment for ssp remote devices
when an ACL link was already established at SDP-level security. This
fix ensures that encryption must be pending whenever authentication
is also pending.
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Tested-by: NDaniel Wagner <daniel.wagner@bmw-carit.de>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

This patch updates the opcodes for mgmt commands and events to match the
latest user space API specification.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>

We only should try to free the SMP channel that was created if there
is a pending SMP session.
Signed-off-by: NVinicius Costa Gomes <vinicius.gomes@openbossa.org>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

There is an imbalance in the rfcomm_session_hold / rfcomm_session_put
operations which causes the following crash:

[  685.010159] BUG: unable to handle kernel paging request at 6b6b6b6b
[  685.010169] IP: [<c149d76d>] rfcomm_process_dlcs+0x1b/0x15e
[  685.010181] *pdpt = 000000002d665001 *pde = 0000000000000000
[  685.010191] Oops: 0000 [#1] PREEMPT SMP
[  685.010247]
[  685.010255] Pid: 947, comm: krfcommd Tainted: G         C  3.0.16-mid8-dirty #44
[  685.010266] EIP: 0060:[<c149d76d>] EFLAGS: 00010246 CPU: 1
[  685.010274] EIP is at rfcomm_process_dlcs+0x1b/0x15e
[  685.010281] EAX: e79f551c EBX: 6b6b6b6b ECX: 00000007 EDX: e79f40b4
[  685.010288] ESI: e79f4060 EDI: ed4e1f70 EBP: ed4e1f68 ESP: ed4e1f50
[  685.010295]  DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
[  685.010303] Process krfcommd (pid: 947, ti=ed4e0000 task=ed43e5e0 task.ti=ed4e0000)
[  685.010308] Stack:
[  685.010312]  ed4e1f68 c149eb53 e5925150 e79f4060 ed500000 ed4e1f70 ed4e1f80 c149ec10
[  685.010331]  00000000 ed43e5e0 00000000 ed4e1f90 ed4e1f9c c149ec87 0000bf54 00000000
[  685.010348]  00000000 ee03bf54 c149ec37 ed4e1fe4 c104fe01 00000000 00000000 00000000
[  685.010367] Call Trace:
[  685.010376]  [<c149eb53>] ? rfcomm_process_rx+0x6e/0x74
[  685.010387]  [<c149ec10>] rfcomm_process_sessions+0xb7/0xde
[  685.010398]  [<c149ec87>] rfcomm_run+0x50/0x6d
[  685.010409]  [<c149ec37>] ? rfcomm_process_sessions+0xde/0xde
[  685.010419]  [<c104fe01>] kthread+0x63/0x68
[  685.010431]  [<c104fd9e>] ? __init_kthread_worker+0x42/0x42
[  685.010442]  [<c14dae82>] kernel_thread_helper+0x6/0xd

This issue has been brought up earlier here:

https://lkml.org/lkml/2011/5/21/127

The issue appears to be the rfcomm_session_put in rfcomm_recv_ua. This
operation doesn't seem be to required as for the non-initiator case we
have the rfcomm_process_rx doing an explicit put and in the initiator
case the last dlc_unlink will drive the reference counter to 0.

There have been several attempts to fix these issue:

6c2718da Bluetooth: Do not call rfcomm_session_put() for RFCOMM UA on closed socket
683d949a Bluetooth: Never deallocate a session when some DLC points to it

but AFAICS they do not fix the issue just make it harder to reproduce.
Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com>
Signed-off-by: NGopala Krishna Murala <gopala.krishna.murala@intel.com>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

This function is not called in interrupt context anymore, so it
should use GFP_KERNEL to allocate memory.
Signed-off-by: NAndre Guedes <aguedespe@gmail.com>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

This makes clear that this is the size of the key used to
encrypt the link.
Signed-off-by: NVinicius Costa Gomes <vinicius.gomes@openbossa.org>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

This defines two new messages, one event that will inform
userspace that a new Long Term Key was exchanged and one that
will allow userspace to load LTKs into the kernel.

Besides the information necessary for the restablishement of
the secure link, we added some extra information: "authenticated"
that informs if the key can be used to establish an authenticated
link, and "master" that informs the role in that the key should
be used.
Signed-off-by: NVinicius Costa Gomes <vinicius.gomes@openbossa.org>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

We need to use the _sync() version for cancelling the info and security
timer in the L2CAP connection delete path. Otherwise the delayed work
handler might run after the connection object is freed.
Signed-off-by: NUlisses Furquim <ulisses@profusion.mobi>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

__cancel_delayed_work() is being used in some paths where we cannot
sleep waiting for the delayed work to finish. However, that function
might return while the timer is running and the work will be queued
again. Replace the calls with safer cancel_delayed_work() version
which spins until the timer handler finishes on other CPUs and
cancels the delayed work.
Signed-off-by: NUlisses Furquim <ulisses@profusion.mobi>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

We don't need locking hdev in hci_conn_timeout() since it doesn't
access any hdev's shared resources, it basically queues HCI commands.
Signed-off-by: NAndre Guedes <andre.guedes@openbossa.org>
Signed-off-by: NVinicius Costa Gomes <vinicius.gomes@openbossa.org>
Reviewed-by: NUlisses Furquim <ulisses@profusion.mobi>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

We don't need to use the _sync variant in hci_conn_hold and
hci_conn_put to cancel conn->disc_work delayed work. This way
we avoid potential deadlocks like this one reported by lockdep.

======================================================
[ INFO: possible circular locking dependency detected ]
3.2.0+ #1 Not tainted
-------------------------------------------------------
kworker/u:1/17 is trying to acquire lock:
 (&hdev->lock){+.+.+.}, at: [<ffffffffa0041155>] hci_conn_timeout+0x62/0x158 [bluetooth]

but task is already holding lock:
 ((&(&conn->disc_work)->work)){+.+...}, at: [<ffffffff81035751>] process_one_work+0x11a/0x2bf

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #2 ((&(&conn->disc_work)->work)){+.+...}:
       [<ffffffff81057444>] lock_acquire+0x8a/0xa7
       [<ffffffff81034ed1>] wait_on_work+0x3d/0xaa
       [<ffffffff81035b54>] __cancel_work_timer+0xac/0xef
       [<ffffffff81035ba4>] cancel_delayed_work_sync+0xd/0xf
       [<ffffffffa00554b0>] smp_chan_create+0xde/0xe6 [bluetooth]
       [<ffffffffa0056160>] smp_conn_security+0xa3/0x12d [bluetooth]
       [<ffffffffa0053640>] l2cap_connect_cfm+0x237/0x2e8 [bluetooth]
       [<ffffffffa004239c>] hci_proto_connect_cfm+0x2d/0x6f [bluetooth]
       [<ffffffffa0046ea5>] hci_event_packet+0x29d1/0x2d60 [bluetooth]
       [<ffffffffa003dde3>] hci_rx_work+0xd0/0x2e1 [bluetooth]
       [<ffffffff810357af>] process_one_work+0x178/0x2bf
       [<ffffffff81036178>] worker_thread+0xce/0x152
       [<ffffffff81039a03>] kthread+0x95/0x9d
       [<ffffffff812e7754>] kernel_thread_helper+0x4/0x10

-> #1 (slock-AF_BLUETOOTH-BTPROTO_L2CAP){+.+...}:
       [<ffffffff81057444>] lock_acquire+0x8a/0xa7
       [<ffffffff812e553a>] _raw_spin_lock_bh+0x36/0x6a
       [<ffffffff81244d56>] lock_sock_nested+0x24/0x7f
       [<ffffffffa004d96f>] lock_sock+0xb/0xd [bluetooth]
       [<ffffffffa0052906>] l2cap_chan_connect+0xa9/0x26f [bluetooth]
       [<ffffffffa00545f8>] l2cap_sock_connect+0xb3/0xff [bluetooth]
       [<ffffffff81243b48>] sys_connect+0x69/0x8a
       [<ffffffff812e6579>] system_call_fastpath+0x16/0x1b

-> #0 (&hdev->lock){+.+.+.}:
       [<ffffffff81056d06>] __lock_acquire+0xa80/0xd74
       [<ffffffff81057444>] lock_acquire+0x8a/0xa7
       [<ffffffff812e3870>] __mutex_lock_common+0x48/0x38e
       [<ffffffff812e3c75>] mutex_lock_nested+0x2a/0x31
       [<ffffffffa0041155>] hci_conn_timeout+0x62/0x158 [bluetooth]
       [<ffffffff810357af>] process_one_work+0x178/0x2bf
       [<ffffffff81036178>] worker_thread+0xce/0x152
       [<ffffffff81039a03>] kthread+0x95/0x9d
       [<ffffffff812e7754>] kernel_thread_helper+0x4/0x10

other info that might help us debug this:

Chain exists of:
  &hdev->lock --> slock-AF_BLUETOOTH-BTPROTO_L2CAP --> (&(&conn->disc_work)->work)

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock((&(&conn->disc_work)->work));
                               lock(slock-AF_BLUETOOTH-BTPROTO_L2CAP);
                               lock((&(&conn->disc_work)->work));
  lock(&hdev->lock);

 *** DEADLOCK ***

2 locks held by kworker/u:1/17:
 #0:  (hdev->name){.+.+.+}, at: [<ffffffff81035751>] process_one_work+0x11a/0x2bf
 #1:  ((&(&conn->disc_work)->work)){+.+...}, at: [<ffffffff81035751>] process_one_work+0x11a/0x2bf

stack backtrace:
Pid: 17, comm: kworker/u:1 Not tainted 3.2.0+ #1
Call Trace:
 [<ffffffff812e06c6>] print_circular_bug+0x1f8/0x209
 [<ffffffff81056d06>] __lock_acquire+0xa80/0xd74
 [<ffffffff81021ef2>] ? arch_local_irq_restore+0x6/0xd
 [<ffffffff81022bc7>] ? vprintk+0x3f9/0x41e
 [<ffffffff81057444>] lock_acquire+0x8a/0xa7
 [<ffffffffa0041155>] ? hci_conn_timeout+0x62/0x158 [bluetooth]
 [<ffffffff812e3870>] __mutex_lock_common+0x48/0x38e
 [<ffffffffa0041155>] ? hci_conn_timeout+0x62/0x158 [bluetooth]
 [<ffffffff81190fd6>] ? __dynamic_pr_debug+0x6d/0x6f
 [<ffffffffa0041155>] ? hci_conn_timeout+0x62/0x158 [bluetooth]
 [<ffffffff8105320f>] ? trace_hardirqs_off+0xd/0xf
 [<ffffffff812e3c75>] mutex_lock_nested+0x2a/0x31
 [<ffffffffa0041155>] hci_conn_timeout+0x62/0x158 [bluetooth]
 [<ffffffff810357af>] process_one_work+0x178/0x2bf
 [<ffffffff81035751>] ? process_one_work+0x11a/0x2bf
 [<ffffffff81055af3>] ? lock_acquired+0x1d0/0x1df
 [<ffffffffa00410f3>] ? hci_acl_disconn+0x65/0x65 [bluetooth]
 [<ffffffff81036178>] worker_thread+0xce/0x152
 [<ffffffff810407ed>] ? finish_task_switch+0x45/0xc5
 [<ffffffff810360aa>] ? manage_workers.isra.25+0x16a/0x16a
 [<ffffffff81039a03>] kthread+0x95/0x9d
 [<ffffffff812e7754>] kernel_thread_helper+0x4/0x10
 [<ffffffff812e5db4>] ? retint_restore_args+0x13/0x13
 [<ffffffff8103996e>] ? __init_kthread_worker+0x55/0x55
 [<ffffffff812e7750>] ? gs_change+0x13/0x13
Signed-off-by: NAndre Guedes <andre.guedes@openbossa.org>
Signed-off-by: NVinicius Costa Gomes <vinicius.gomes@openbossa.org>
Reviewed-by: NUlisses Furquim <ulisses@profusion.mobi>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>