From b5a30dda6598af216c070165ece6068f9f00f33a Mon Sep 17 00:00:00 2001 From: Octavian Purdila Date: Sun, 22 Jan 2012 00:28:34 +0200 Subject: Bluetooth: silence lockdep warning 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: [] 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: [] 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] [] lock_acquire+0x104/0x140 <4>[ 1864.738977] [] lock_sock_nested+0x58/0x68 <4>[ 1864.739411] [] l2cap_sock_sendmsg+0x3e/0x76 <4>[ 1864.739858] [] __sock_sendmsg+0x50/0x59 <4>[ 1864.740279] [] sock_sendmsg+0x94/0xa8 <4>[ 1864.740687] [] kernel_sendmsg+0x28/0x37 <4>[ 1864.741106] [] rfcomm_send_frame+0x30/0x38 <4>[ 1864.741542] [] rfcomm_send_ua+0x58/0x5a <4>[ 1864.741959] [] rfcomm_run+0x441/0xb52 <4>[ 1864.742365] [] kthread+0x63/0x68 <4>[ 1864.742742] [] kernel_thread_helper+0x6/0xd <4>[ 1864.743187] <4>[ 1864.743193] -> #0 (rfcomm_mutex){+.+.+.}: <4>[ 1864.743667] [] __lock_acquire+0x988/0xc00 <4>[ 1864.744100] [] lock_acquire+0x104/0x140 <4>[ 1864.744519] [] __mutex_lock_common+0x3b/0x33f <4>[ 1864.744975] [] mutex_lock_nested+0x2d/0x36 <4>[ 1864.745412] [] rfcomm_dlc_close+0x15/0x30 <4>[ 1864.745842] [] __rfcomm_sock_close+0x5f/0x6b <4>[ 1864.746288] [] rfcomm_sock_shutdown+0x2f/0x62 <4>[ 1864.746737] [] sys_socketcall+0x1db/0x422 <4>[ 1864.747165] [] syscall_call+0x7/0xb Signed-off-by: Octavian Purdila Acked-by: Marcel Holtmann Signed-off-by: Johan Hedberg --- net/bluetooth/af_bluetooth.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) (limited to 'net/bluetooth/af_bluetooth.c') diff --git a/net/bluetooth/af_bluetooth.c b/net/bluetooth/af_bluetooth.c index ef92864ac625..72eb187a5f60 100644 --- a/net/bluetooth/af_bluetooth.c +++ b/net/bluetooth/af_bluetooth.c @@ -71,19 +71,16 @@ static const char *const bt_slock_key_strings[BT_MAX_PROTO] = { "slock-AF_BLUETOOTH-BTPROTO_AVDTP", }; -static inline void bt_sock_reclassify_lock(struct socket *sock, int proto) +void bt_sock_reclassify_lock(struct sock *sk, int proto) { - struct sock *sk = sock->sk; - - if (!sk) - return; - + BUG_ON(!sk); BUG_ON(sock_owned_by_user(sk)); sock_lock_init_class_and_name(sk, bt_slock_key_strings[proto], &bt_slock_key[proto], bt_key_strings[proto], &bt_lock_key[proto]); } +EXPORT_SYMBOL(bt_sock_reclassify_lock); int bt_sock_register(int proto, const struct net_proto_family *ops) { @@ -145,7 +142,8 @@ static int bt_sock_create(struct net *net, struct socket *sock, int proto, if (bt_proto[proto] && try_module_get(bt_proto[proto]->owner)) { err = bt_proto[proto]->create(net, sock, proto, kern); - bt_sock_reclassify_lock(sock, proto); + if (!err) + bt_sock_reclassify_lock(sock->sk, proto); module_put(bt_proto[proto]->owner); } -- cgit v1.2.3