=============================================
[ INFO: possible recursive locking detected ]
---------------------------------------------
java/6743 is trying to acquire lock:
 (slock-AF_INET6){-+..}, at: [<c03be6f4>] sk_clone+0xf4/0x310

but task is already holding lock:
 (slock-AF_INET6){-+..}, at: [<c0444eaf>] tcp_v6_rcv+0x34f/0x6f0

other info that might help us debug this:
1 lock held by java/6743:
 #0:  (slock-AF_INET6){-+..}, at: [<c0444eaf>] tcp_v6_rcv+0x34f/0x6f0

stack backtrace:
 [<c01034b9>] show_trace+0x19/0x20
 [<c01035ba>] dump_stack+0x1a/0x20
 [<c0131454>] print_deadlock_bug+0xa4/0xb0
 [<c01314ca>] check_deadlock+0x6a/0x80
 [<c0132cf7>] __lock_acquire+0x4f7/0x950
 [<c01337cd>] lock_acquire+0x5d/0x80
 [<c0483415>] _spin_lock+0x25/0x30
 [<c03be6f4>] sk_clone+0xf4/0x310
 [<c03e6b31>] inet_csk_clone+0x11/0x70
 [<c03fb3c5>] tcp_create_openreq_child+0x15/0x3e0
 [<c04442c2>] tcp_v6_syn_recv_sock+0x142/0x610
 [<c03fb8a9>] tcp_check_req+0x119/0x420
 [<c0443d75>] tcp_v6_hnd_req+0x45/0x130
 [<c0444af7>] tcp_v6_do_rcv+0x247/0x2b0
 [<c0445136>] tcp_v6_rcv+0x5d6/0x6f0
 [<c04272df>] ip6_input+0x16f/0x340
 [<c0427004>] ipv6_rcv+0x114/0x280
 [<c03c6eb1>] netif_receive_skb+0x1b1/0x1f0
 [<c03c6f80>] process_backlog+0x90/0x120
 [<c03c707d>] net_rx_action+0x6d/0x100
 [<c011d68f>] __do_softirq+0x6f/0x100
 [<c0104de7>] do_softirq+0x87/0xe0
 =======================
 [<c011d5d9>] local_bh_enable_ip+0xb9/0x100
 [<c0483661>] _spin_unlock_bh+0x31/0x40
 [<c03bf750>] release_sock+0x50/0xb0
 [<c0405647>] inet_wait_for_connect+0x67/0xd0
 [<c0405748>] inet_stream_connect+0x98/0x1d0
 [<c03bc6d7>] sys_connect+0x67/0xa0
 [<c03bd1c6>] sys_socketcall+0xc6/0x1e0
 [<c0102e77>] syscall_call+0x7/0xb

[reboot]