Re: [ANNOUNCE] 2.6.33.6-rt26

Dhaval Giani
2010-07-13T16:52:24Z

Hi,

> Enjoy !
>

I hit this with rt26. (Quite possible is on vanilla as well, will
build a kernel soemtime soon and try)

=======================================================
[ INFO: possible circular locking dependency detected ]
2.6.33.6-rt26 #36
-------------------------------------------------------
iperf/1629 is trying to acquire lock:
(slock-AF_INET){+.+...}, at: [<ffffffff8135a4fa>] release_sock+0x30/0x108

but task is already holding lock:
(&lock->lock){+.+...}, at: [<ffffffff813cd6cc>] ipt_do_table+0x118/0x650

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (&lock->lock){+.+...}:
[<ffffffff810697e7>] lock_acquire+0xd6/0xfa
[<ffffffff813fcfaa>] rt_spin_lock+0x31/0x38
[<ffffffffa00ba8ef>] nf_nat_get_offset+0x42/0x6b [nf_nat]
[<ffffffff8138b2ba>] tcp_packet+0x659/0xd5b
[<ffffffff81387eb9>] nf_conntrack_in+0x445/0x4fc
[<ffffffff813ca933>] ipv4_conntrack_local+0x3b/0x44
[<ffffffff81384c22>] nf_iterate+0x41/0x84
[<ffffffff81384cd8>] nf_hook_slow+0x73/0xdb
[<ffffffff813970b4>] nf_hook_thresh.clone.0+0x3c/0x45
[<ffffffff81397136>] __ip_local_out+0x79/0x7b
[<ffffffff81397149>] ip_local_out+0x11/0x22
[<ffffffff81397407>] ip_push_pending_frames+0x2ad/0x30b
[<ffffffff81398a41>] ip_send_reply+0x21a/0x259
[<ffffffff813acdf1>] tcp_v4_send_reset+0x1c8/0x1eb
[<ffffffff813b0367>] tcp_v4_rcv+0x500/0x661
[<ffffffff8139400a>] ip_local_deliver_finish+0x14d/0x1c3
[<ffffffff813940f2>] ip_local_deliver+0x72/0x7c
[<ffffffff81393ac3>] ip_rcv_finish+0x31a/0x346
[<ffffffff81393d29>] ip_rcv+0x23a/0x268
[<ffffffff81366862>] netif_receive_skb+0x3fa/0x424
[<ffffffffa023fb41>] br_handle_frame_finish+0x105/0x13d [bridge]
[<ffffffffa023fd08>] br_handle_frame+0x18f/0x1a7 [bridge]
[<ffffffff81366792>] netif_receive_skb+0x32a/0x424
[<ffffffff813669d4>] napi_skb_finish+0x24/0x3b
[<ffffffff81366e83>] napi_gro_receive+0x2a/0x2f
[<ffffffff812d03b9>] sky2_poll+0x86e/0xaef
[<ffffffff81366fcc>] net_rx_action+0xa3/0x1f1
[<ffffffff81044a02>] run_ksoftirqd+0x14e/0x254
[<ffffffff8105975f>] kthread+0x88/0x90
[<ffffffff81009844>] kernel_thread_helper+0x4/0x10

-> #0 (slock-AF_INET){+.+...}:
[<ffffffff8106941a>] __lock_acquire+0x9f1/0xce8
[<ffffffff810697e7>] lock_acquire+0xd6/0xfa
[<ffffffff813fcfaa>] rt_spin_lock+0x31/0x38
[<ffffffff8135a4fa>] release_sock+0x30/0x108
[<ffffffff813a012a>] tcp_recvmsg+0x8b8/0x9a3
[<ffffffff81359864>] sock_common_recvmsg+0x37/0x48
[<ffffffff81357178>] __sock_recvmsg+0x6d/0x78

(Just run iperf as server and test it from another system)

thanks,
Dhaval