BUG: soft lockup - CPU#0 stuck for 67s!

>Description of problem:
Server hangs.

>How reproducible:
Don't know...
The problem occurs at a random time, but very often.

>Host OS:
CentOS 6

>Kernel:
2.6.32-042stab117.6

Part of log with soft lockup:
2016-07-29T10:08:36.787585+03:00 localhost [164824.808248] BUG: soft lockup - CPU#0 stuck for 67s! [python:21512]
2016-07-29T10:08:36.787585+03:00 localhost [164824.808505] Modules linked in:
........
2016-07-29T10:08:36.812730+03:00 localhost
2016-07-29T10:08:36.812955+03:00 localhost [164824.833681]
2016-07-29T10:08:36.813207+03:00 localhost [164824.833914] Pid: 21512, comm: python veid: 256 Not tainted 2.6.32-042stab117.6 #1 042stab117_6
2016-07-29T10:08:36.813297+03:00 localhost Supermicro SYS-5019S-M
2016-07-29T10:08:36.813397+03:00 localhost /X11SSH-F
2016-07-29T10:08:36.813624+03:00 localhost
2016-07-29T10:08:36.813733+03:00 localhost [164824.834591] RIP: 0010:[<ffffffff8155653e>]
2016-07-29T10:08:36.814107+03:00 localhost [<ffffffff8155653e>] _spin_lock+0x1e/0x30
2016-07-29T10:08:36.814347+03:00 localhost [164824.835069] RSP: 0018:ffff8810359dbe48 EFLAGS: 00000297
2016-07-29T10:08:36.814725+03:00 localhost [164824.835311] RAX: 000000000000a7a9 RBX: ffff8810359dbe48 RCX: 00000000000003ca
2016-07-29T10:08:36.815102+03:00 localhost [164824.835687] RDX: 000000000000a7a8 RSI: ffffffff81a86380 RDI: ffffffff81a86380
2016-07-29T10:08:36.815483+03:00 localhost [164824.836064] RBP: ffffffff8100bcce R08: ffffffff81c20580 R09: 0000000000000000
2016-07-29T10:08:36.815859+03:00 localhost [164824.836441] R10: 0000000000000001 R11: 0000000000000001 R12: ffff880ea2a757c0
2016-07-29T10:08:36.816235+03:00 localhost [164824.836817] R13: ffff8810359dbdf8 R14: 0000000100000000 R15: ffff880ea2a75e70
2016-07-29T10:08:36.816606+03:00 localhost [164824.837194] FS: 00007effd35fe700(0000) GS:ffff880028200000(0000) knlGS:0000000000000000
2016-07-29T10:08:36.816869+03:00 localhost [164824.837573] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
2016-07-29T10:08:36.817232+03:00 localhost [164824.837814] CR2: 00007fe66fdd9454 CR3: 000000103fa1c000 CR4: 00000000001407f0
2016-07-29T10:08:36.817619+03:00 localhost [164824.838191] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
2016-07-29T10:08:36.817994+03:00 localhost [164824.838568] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
2016-07-29T10:08:36.818383+03:00 localhost [164824.838945] Process python (pid: 21512, veid: 256, threadinfo ffff8810359d8000, task ffff880fa875e880)
2016-07-29T10:08:36.818636+03:00 localhost [164824.839325] Stack:
2016-07-29T10:08:36.818738+03:00 localhost [164824.839559] ffff8810359dbe78
2016-07-29T10:08:36.818802+03:00 localhost ffffffff812a9965
2016-07-29T10:08:36.818913+03:00 localhost ffffffff81ac0000
2016-07-29T10:08:36.819127+03:00 localhost ffffffff81a86380
2016-07-29T10:08:36.819376+03:00 localhost
2016-07-29T10:08:36.819477+03:00 localhost [164824.840095] <d>
2016-07-29T10:08:36.819567+03:00 localhost ffff8810359dbe98
2016-07-29T10:08:36.819648+03:00 localhost ffff880c4d56c318
2016-07-29T10:08:36.819776+03:00 localhost ffff8810359dbea8
2016-07-29T10:08:36.819989+03:00 localhost ffffffff811dcd59
2016-07-29T10:08:36.820258+03:00 localhost
2016-07-29T10:08:36.820320+03:00 localhost [164824.840957] <d>
2016-07-29T10:08:36.820417+03:00 localhost ffff880286ad7080
2016-07-29T10:08:36.820540+03:00 localhost 0000000000000008
2016-07-29T10:08:36.820642+03:00 localhost ffff880ae167d108
2016-07-29T10:08:36.820850+03:00 localhost ffff880c4d56c318
2016-07-29T10:08:36.821087+03:00 localhost
2016-07-29T10:08:36.821334+03:00 localhost [164824.842047] Call Trace:
2016-07-29T10:08:36.821574+03:00 localhost [164824.842284] [<ffffffff812a9965>] ? _atomic_dec_and_lock+0x55/0x80
2016-07-29T10:08:36.821818+03:00 localhost [164824.842528] [<ffffffff811dcd59>] ? dput_nocache+0x39/0x260
2016-07-29T10:08:36.822059+03:00 localhost [164824.842770] [<ffffffff811dcf90>] ? dput+0x10/0x20
2016-07-29T10:08:36.822309+03:00 localhost [164824.843011] [<ffffffff811c2574>] ? __fput+0x1d4/0x280
2016-07-29T10:08:36.822573+03:00 localhost [164824.843252] [<ffffffff811c2645>] ? fput+0x25/0x30
2016-07-29T10:08:36.822784+03:00 localhost [164824.843493] [<ffffffff811bcd9d>] ? filp_close+0x5d/0x90
2016-07-29T10:08:36.823035+03:00 localhost [164824.843734] [<ffffffff811bce75>] ? sys_close+0xa5/0x100
2016-07-29T10:08:36.823261+03:00 localhost [164824.843976] [<ffffffff8100b1a2>] ? system_call_fastpath+0x16/0x1b
2016-07-29T10:08:36.823391+03:00 localhost [164824.844220]
2016-07-29T10:08:36.830123+03:00 localhost
2016-07-29T10:08:36.830359+03:00 localhost [164824.851054] Call Trace:
2016-07-29T10:08:36.830597+03:00 localhost [164824.851289] [<ffffffff812a9965>] ? _atomic_dec_and_lock+0x55/0x80
2016-07-29T10:08:36.830839+03:00 localhost [164824.851532] [<ffffffff811dcd59>] ? dput_nocache+0x39/0x260
2016-07-29T10:08:36.831081+03:00 localhost [164824.851774] [<ffffffff811dcf90>] ? dput+0x10/0x20
2016-07-29T10:08:36.831321+03:00 localhost [164824.852014] [<ffffffff811c2574>] ? __fput+0x1d4/0x280
2016-07-29T10:08:36.831560+03:00 localhost [164824.852255] [<ffffffff811c2645>] ? fput+0x25/0x30
2016-07-29T10:08:36.831802+03:00 localhost [164824.852495] [<ffffffff811bcd9d>] ? filp_close+0x5d/0x90
2016-07-29T10:08:36.832043+03:00 localhost [164824.852737] [<ffffffff811bce75>] ? sys_close+0xa5/0x100
2016-07-29T10:08:36.832294+03:00 localhost [164824.852978] [<ffffffff8100b1a2>] ? system_call_fastpath+0x16/0x1b

Full log in attachments.