4.14-stable review patch. If anyone has any objections, please let me know.
------------------
From: Philipp Puschmann pp@emlix.com
[ Upstream commit b71c69c26b4916d11b8d403d8e667bbd191f1b8f ]
Fixes this warning that was provoked by a pairing:
[60258.016221] WARNING: possible recursive locking detected [60258.021558] 4.15.0-RD1812-BSP #1 Tainted: G O [60258.027146] -------------------------------------------- [60258.032464] kworker/u5:0/70 is trying to acquire lock: [60258.037609] (sk_lock-AF_BLUETOOTH-BTPROTO_L2CAP){+.+.}, at: [<87759073>] bt_accept_enqueue+0x3c/0x74 [60258.046863] [60258.046863] but task is already holding lock: [60258.052704] (sk_lock-AF_BLUETOOTH-BTPROTO_L2CAP){+.+.}, at: [<d22d7106>] l2cap_sock_new_connection_cb+0x1c/0x88 [60258.062905] [60258.062905] other info that might help us debug this: [60258.069441] Possible unsafe locking scenario: [60258.069441] [60258.075368] CPU0 [60258.077821] ---- [60258.080272] lock(sk_lock-AF_BLUETOOTH-BTPROTO_L2CAP); [60258.085510] lock(sk_lock-AF_BLUETOOTH-BTPROTO_L2CAP); [60258.090748] [60258.090748] *** DEADLOCK *** [60258.090748] [60258.096676] May be due to missing lock nesting notation [60258.096676] [60258.103472] 5 locks held by kworker/u5:0/70: [60258.107747] #0: ((wq_completion)%shdev->name#2){+.+.}, at: [<9460d092>] process_one_work+0x130/0x4fc [60258.117263] #1: ((work_completion)(&hdev->rx_work)){+.+.}, at: [<9460d092>] process_one_work+0x130/0x4fc [60258.126942] #2: (&conn->chan_lock){+.+.}, at: [<7877c8c3>] l2cap_connect+0x80/0x4f8 [60258.134806] #3: (&chan->lock/2){+.+.}, at: [<2e16c724>] l2cap_connect+0x8c/0x4f8 [60258.142410] #4: (sk_lock-AF_BLUETOOTH-BTPROTO_L2CAP){+.+.}, at: [<d22d7106>] l2cap_sock_new_connection_cb+0x1c/0x88 [60258.153043] [60258.153043] stack backtrace: [60258.157413] CPU: 1 PID: 70 Comm: kworker/u5:0 Tainted: G O 4.15.0-RD1812-BSP #1 [60258.165945] Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree) [60258.172485] Workqueue: hci0 hci_rx_work [60258.176331] Backtrace: [60258.178797] [<8010c9fc>] (dump_backtrace) from [<8010ccbc>] (show_stack+0x18/0x1c) [60258.186379] r7:80e55fe4 r6:80e55fe4 r5:20050093 r4:00000000 [60258.192058] [<8010cca4>] (show_stack) from [<809864e8>] (dump_stack+0xb0/0xdc) [60258.199301] [<80986438>] (dump_stack) from [<8016ecc8>] (__lock_acquire+0xffc/0x11d4) [60258.207144] r9:5e2bb019 r8:630f974c r7:ba8a5940 r6:ba8a5ed8 r5:815b5220 r4:80fa081c [60258.214901] [<8016dccc>] (__lock_acquire) from [<8016f620>] (lock_acquire+0x78/0x98) [60258.222655] r10:00000040 r9:00000040 r8:808729f0 r7:00000001 r6:00000000 r5:60050013 [60258.230491] r4:00000000 [60258.233045] [<8016f5a8>] (lock_acquire) from [<806ee974>] (lock_sock_nested+0x64/0x88) [60258.240970] r7:00000000 r6:b796e870 r5:00000001 r4:b796e800 [60258.246643] [<806ee910>] (lock_sock_nested) from [<808729f0>] (bt_accept_enqueue+0x3c/0x74) [60258.255004] r8:00000001 r7:ba7d3c00 r6:ba7d3ea4 r5:ba7d2000 r4:b796e800 [60258.261717] [<808729b4>] (bt_accept_enqueue) from [<808aa39c>] (l2cap_sock_new_connection_cb+0x68/0x88) [60258.271117] r5:b796e800 r4:ba7d2000 [60258.274708] [<808aa334>] (l2cap_sock_new_connection_cb) from [<808a294c>] (l2cap_connect+0x190/0x4f8) [60258.283933] r5:00000001 r4:ba6dce00 [60258.287524] [<808a27bc>] (l2cap_connect) from [<808a4a14>] (l2cap_recv_frame+0x744/0x2cf8) [60258.295800] r10:ba6dcf24 r9:00000004 r8:b78d8014 r7:00000004 r6:bb05d000 r5:00000004 [60258.303635] r4:bb05d008 [60258.306183] [<808a42d0>] (l2cap_recv_frame) from [<808a7808>] (l2cap_recv_acldata+0x210/0x214) [60258.314805] r10:b78e7800 r9:bb05d960 r8:00000001 r7:bb05d000 r6:0000000c r5:b7957a80 [60258.322641] r4:ba6dce00 [60258.325188] [<808a75f8>] (l2cap_recv_acldata) from [<8087630c>] (hci_rx_work+0x35c/0x4e8) [60258.333374] r6:80e5743c r5:bb05d7c8 r4:b7957a80 [60258.338004] [<80875fb0>] (hci_rx_work) from [<8013dc7c>] (process_one_work+0x1a4/0x4fc) [60258.346018] r10:00000001 r9:00000000 r8:baabfef8 r7:ba997500 r6:baaba800 r5:baaa5d00 [60258.353853] r4:bb05d7c8 [60258.356401] [<8013dad8>] (process_one_work) from [<8013e028>] (worker_thread+0x54/0x5cc) [60258.364503] r10:baabe038 r9:baaba834 r8:80e05900 r7:00000088 r6:baaa5d18 r5:baaba800 [60258.372338] r4:baaa5d00 [60258.374888] [<8013dfd4>] (worker_thread) from [<801448f8>] (kthread+0x134/0x160) [60258.382295] r10:ba8310b8 r9:bb07dbfc r8:8013dfd4 r7:baaa5d00 r6:00000000 r5:baaa8ac0 [60258.390130] r4:ba831080 [60258.392682] [<801447c4>] (kthread) from [<801080b4>] (ret_from_fork+0x14/0x20) [60258.399915] r10:00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:801447c4 [60258.407751] r4:baaa8ac0 r3:baabe000
Signed-off-by: Philipp Puschmann pp@emlix.com Signed-off-by: Marcel Holtmann marcel@holtmann.org Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/bluetooth/af_bluetooth.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/net/bluetooth/af_bluetooth.c +++ b/net/bluetooth/af_bluetooth.c @@ -159,7 +159,7 @@ void bt_accept_enqueue(struct sock *pare BT_DBG("parent %p, sk %p", parent, sk);
sock_hold(sk); - lock_sock(sk); + lock_sock_nested(sk, SINGLE_DEPTH_NESTING); list_add_tail(&bt_sk(sk)->accept_q, &bt_sk(parent)->accept_q); bt_sk(sk)->parent = parent; release_sock(sk);