softlocks in 55.7

Hi,

While doing migrations to a box we have the following softlock. I'm not sure if it's related to the migration or what, but here's the call trace:


May 7 13:33:26 205.185.112.214 [42708.024089] Pid: 178888, comm: grep veid: 0 Not tainted 2.6.32-042stab055.7 #1 042stab055_7 Bochs Bochs
May 7 13:33:26 205.185.112.214 [42708.024089] RIP: 0010:[<ffffffff814ea426>] [<ffffffff814ea426>] _spin_lock+0x26/0x30
May 7 13:33:26 205.185.112.214 [42708.024089] RSP: 0018:ffff880005a6bce8 EFLAGS: 00000206
May 7 13:33:26 205.185.112.214 [42708.024089] RAX: 0000000000000006 RBX: ffff880005a6bce8 RCX: 0000000000000001
May 7 13:33:26 205.185.112.214 [42708.024089] RDX: 0000000000000000 RSI: ffffffff823d2a60 RDI: ffffffff823d2a60
May 7 13:33:26 205.185.112.214 [42708.024089] RBP: ffffffff8100bcce R08: ffff8800052bf5e8 R09: 000000000001eb78
May 7 13:33:26 205.185.112.214 [42708.024089] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88021f128ec0
May 7 13:33:26 205.185.112.214 [42708.024089] R13: ffff880000021d00 R14: ffffea0004140280 R15: ffff880005a6bcc8
May 7 13:33:26 205.185.112.214 [42708.024089] FS: 0000000000000000(0000) GS:ffff880028240000(0000) knlGS:0000000000000000
May 7 13:33:26 205.185.112.214 [42708.024089] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
May 7 13:33:26 205.185.112.214 [42708.024089] CR2: 00007fcaa4abaae0 CR3: 0000000001a85000 CR4: 00000000000006e0
May 7 13:33:26 205.185.112.214 [42708.024089] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
May 7 13:33:26 205.185.112.214 [42708.024089] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
May 7 13:33:26 205.185.112.214 [42708.024089] Process grep (pid: 178888, veid: 0, threadinfo ffff880005a6a000, task ffff8800083026c0)
May 7 13:33:26 205.185.112.214 [42708.024089] Stack:
May 7 13:33:26 205.185.112.214 [42708.024089] ffff880005a6bd18 ffffffff81269c15 0000000000000001 ffffffff823d2a60
May 7 13:33:26 205.185.112.214 [42708.024089] <0> ffff880005a6bd38 ffff880101253048 ffff880005a6bd38 ffffffff811ac030
May 7 13:33:26 205.185.112.214 [42708.024089] <0> ffff880101253048 ffff8800052bf588 ffff880005a6bd58 ffffffff811a88a8
May 7 13:33:26 205.185.112.214 [42708.024089] Call Trace:
May 7 13:33:26 205.185.112.214 [42708.024089] [<ffffffff81269c15>] ? _atomic_dec_and_lock+0x55/0x80
May 7 13:33:26 205.185.112.214 [42708.024089] [<ffffffff811ac030>] ? iput+0x30/0x70
May 7 13:33:26 205.185.112.214 [42708.024089] [<ffffffff811a88a8>] ? dentry_iput+0x98/0x110
May 7 13:33:26 205.185.112.214 [42708.024089] [<ffffffff811a8a1c>] ? d_kill+0x3c/0x70
May 7 13:33:26 205.185.112.214 [42708.024089] [<ffffffff811aa1b3>] ? dput+0xa3/0x1d0
May 7 13:33:26 205.185.112.214 [42708.024089] [<ffffffff81193224>] ? __fput+0x1d4/0x280
May 7 13:33:26 205.185.112.214 [42708.024089] [<ffffffff811932f5>] ? fput+0x25/0x30
May 7 13:33:26 205.185.112.214 [42708.024089] [<ffffffff8118e45d>] ? filp_close+0x5d/0x90
May 7 13:33:26 205.185.112.214 [42708.024089] [<ffffffff8106f0bf>] ? put_files_struct+0x7f/0xf0
May 7 13:33:26 205.185.112.214 [42708.024089] [<ffffffff8106f183>] ? exit_files+0x53/0x70
May 7 13:33:26 205.185.112.214 [42708.024089] [<ffffffff81070d4d>] ? do_exit+0x1ad/0x920
May 7 13:33:26 205.185.112.214 [42708.024089] [<ffffffff81071518>] ? do_group_exit+0x58/0xd0
May 7 13:33:26 205.185.112.214 [42708.024089] [<ffffffff810715a7>] ? sys_exit_group+0x17/0x20
May 7 13:33:26 205.185.112.214 [42708.024089] [<ffffffff8100b182>] ? system_call_fastpath+0x16/0x1b
May 7 13:33:26 205.185.112.214 [42708.024089] Code: cb d8 ff c9 c3 55 48 89 e5 0f 1f 44 00 00 b8 00 00 01 00 f0 0f c1 07 0f b7 d0 c1 e8 10 39 c2 74 0e f3 90 0f 1f 44 00 00 83 3f 00 <75> f4 eb df c9 c3 0f 1f 40 00 55 48 89 e5 0f 1f 44 00
 00 f0 81
May 7 13:33:26 205.185.112.214 [42708.024089] Call Trace:
May 7 13:33:26 205.185.112.214 [42708.024089] [<ffffffff81269c15>] ? _atomic_dec_and_lock+0x55/0x80
May 7 13:33:26 205.185.112.214 [42708.024089] [<ffffffff811ac030>] ? iput+0x30/0x70
May 7 13:33:26 205.185.112.214 [42708.024089] [<ffffffff811a88a8>] ? dentry_iput+0x98/0x110
May 7 13:33:26 205.185.112.214 [42708.024089] [<ffffffff811a8a1c>] ? d_kill+0x3c/0x70
May 7 13:33:26 205.185.112.214 [42708.024089] [<ffffffff811aa1b3>] ? dput+0xa3/0x1d0
May 7 13:33:26 205.185.112.214 [42708.024089] [<ffffffff81193224>] ? __fput+0x1d4/0x280
May 7 13:33:26 205.185.112.214 [42708.024089] [<ffffffff811932f5>] ? fput+0x25/0x30
May 7 13:33:26 205.185.112.214 [42708.024089] [<ffffffff8118e45d>] ? filp_close+0x5d/0x90
May 7 13:33:26 205.185.112.214 [42708.024089] [<ffffffff8106f0bf>] ? put_files_struct+0x7f/0xf0
May 7 13:33:26 205.185.112.214 [42708.024089] [<ffffffff8106f183>] ? exit_files+0x53/0x70
May 7 13:33:26 205.185.112.214 [42708.024089] [<ffffffff81070d4d>] ? do_exit+0x1ad/0x920
May 7 13:33:26 205.185.112.214 [42708.024089] [<ffffffff81071518>] ? do_group_exit+0x58/0xd0
May 7 13:33:26 205.185.112.214 [42708.024089] [<ffffffff810715a7>] ? sys_exit_group+0x17/0x20
May 7 13:33:26 205.185.112.214 [42708.024089] [<ffffffff8100b182>] ? system_call_fastpath+0x16/0x1b

I have a full netconsole I can submit as well if you need more.

Thanks!

Francisco