From: Johan Hedberg <johan.hedberg@gmail.com>
To: Marcel Holtmann <marcel@holtmann.org>
Cc: Octavian Purdila <tavi.purdila@gmail.com>,
linux-bluetooth@vger.kernel.org, kirill.shutemov@linux.intel.com,
Octavian Purdila <octavian.purdila@intel.com>
Subject: Re: [PATCH v4] Bluetooth: silence lockdep warning
Date: Mon, 23 Jan 2012 11:12:51 +0200 [thread overview]
Message-ID: <20120123091251.GD8800@x220> (raw)
In-Reply-To: <1327224111.1955.72.camel@aeonflux>
Hi,
On Sun, Jan 22, 2012, Marcel Holtmann wrote:
> > Since bluetooth uses multiple protocols types, to avoid lockdep
> > warnings, we need to use different lockdep classes (one for each
> > protocol type).
> >
> > This is already done in bt_sock_create but it misses a couple of cases
> > when new connections are created. This patch corrects that to fix the
> > following warning:
> >
> > <4>[ 1864.732366] =======================================================
> > <4>[ 1864.733030] [ INFO: possible circular locking dependency detected ]
> > <4>[ 1864.733544] 3.0.16-mid3-00007-gc9a0f62 #3
> > <4>[ 1864.733883] -------------------------------------------------------
> > <4>[ 1864.734408] t.android.btclc/4204 is trying to acquire lock:
> > <4>[ 1864.734869] (rfcomm_mutex){+.+.+.}, at: [<c14970ea>] rfcomm_dlc_close+0x15/0x30
> > <4>[ 1864.735541]
> > <4>[ 1864.735549] but task is already holding lock:
> > <4>[ 1864.736045] (sk_lock-AF_BLUETOOTH){+.+.+.}, at: [<c1498bf7>] lock_sock+0xa/0xc
> > <4>[ 1864.736732]
> > <4>[ 1864.736740] which lock already depends on the new lock.
> > <4>[ 1864.736750]
> > <4>[ 1864.737428]
> > <4>[ 1864.737437] the existing dependency chain (in reverse order) is:
> > <4>[ 1864.738016]
> > <4>[ 1864.738023] -> #1 (sk_lock-AF_BLUETOOTH){+.+.+.}:
> > <4>[ 1864.738549] [<c1062273>] lock_acquire+0x104/0x140
> > <4>[ 1864.738977] [<c13d35c1>] lock_sock_nested+0x58/0x68
> > <4>[ 1864.739411] [<c1493c33>] l2cap_sock_sendmsg+0x3e/0x76
> > <4>[ 1864.739858] [<c13d06c3>] __sock_sendmsg+0x50/0x59
> > <4>[ 1864.740279] [<c13d0ea2>] sock_sendmsg+0x94/0xa8
> > <4>[ 1864.740687] [<c13d0ede>] kernel_sendmsg+0x28/0x37
> > <4>[ 1864.741106] [<c14969ca>] rfcomm_send_frame+0x30/0x38
> > <4>[ 1864.741542] [<c1496a2a>] rfcomm_send_ua+0x58/0x5a
> > <4>[ 1864.741959] [<c1498447>] rfcomm_run+0x441/0xb52
> > <4>[ 1864.742365] [<c104f095>] kthread+0x63/0x68
> > <4>[ 1864.742742] [<c14d5182>] kernel_thread_helper+0x6/0xd
> > <4>[ 1864.743187]
> > <4>[ 1864.743193] -> #0 (rfcomm_mutex){+.+.+.}:
> > <4>[ 1864.743667] [<c1061ada>] __lock_acquire+0x988/0xc00
> > <4>[ 1864.744100] [<c1062273>] lock_acquire+0x104/0x140
> > <4>[ 1864.744519] [<c14d2c70>] __mutex_lock_common+0x3b/0x33f
> > <4>[ 1864.744975] [<c14d303e>] mutex_lock_nested+0x2d/0x36
> > <4>[ 1864.745412] [<c14970ea>] rfcomm_dlc_close+0x15/0x30
> > <4>[ 1864.745842] [<c14990d9>] __rfcomm_sock_close+0x5f/0x6b
> > <4>[ 1864.746288] [<c1499114>] rfcomm_sock_shutdown+0x2f/0x62
> > <4>[ 1864.746737] [<c13d275d>] sys_socketcall+0x1db/0x422
> > <4>[ 1864.747165] [<c14d42f0>] syscall_call+0x7/0xb
> >
> > Signed-off-by: Octavian Purdila <octavian.purdila@intel.com>
> > ---
> > include/net/bluetooth/bluetooth.h | 2 ++
> > net/bluetooth/af_bluetooth.c | 12 +++++-------
> > net/bluetooth/l2cap_sock.c | 2 ++
> > net/bluetooth/rfcomm/sock.c | 2 ++
> > 4 files changed, 11 insertions(+), 7 deletions(-)
>
> Acked-by: Marcel Holtmann <marcel@holtmann.org>
Applied. Thanks.
Johan
prev parent reply other threads:[~2012-01-23 9:12 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-01-21 22:28 [PATCH v4] Bluetooth: silence lockdep warning Octavian Purdila
2012-01-22 9:21 ` Marcel Holtmann
2012-01-23 9:12 ` Johan Hedberg [this message]
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