Re: [Bug #12612] hard lockup when interrupting cdda2wav

["Rafael J. Wysocki" <rjw-KKrjLPT3xs0@public.gmane.org>]

On Tuesday 17 February 2009, Matthias Reichl wrote:
> The bug is still present in 2.6.28.5:
> 
> =============================================
> [ INFO: possible recursive locking detected ]
> 2.6.28.5-dbg #1
> ---------------------------------------------
> swapper/0 is trying to acquire lock:
>  (&q->__queue_lock){.+..}, at: [<ffffffff8040e615>] blk_put_request+0x25/0x60
> 
> but task is already holding lock:
>  (&q->__queue_lock){.+..}, at: [<ffffffff8040e4fa>] blk_end_io+0x5a/0xa0
> 
> other info that might help us debug this:
> 1 lock held by swapper/0:
>  #0:  (&q->__queue_lock){.+..}, at: [<ffffffff8040e4fa>] blk_end_io+0x5a/0xa0
> 
> stack backtrace:
> Pid: 0, comm: swapper Not tainted 2.6.28.5-dbg #1
> Call Trace:
>  <IRQ>  [<ffffffff8026cd07>] __lock_acquire+0x1797/0x1930
>  [<ffffffff806abf8b>] error_exit+0x29/0xa9
>  [<ffffffff80521f40>] sg_rq_end_io+0x0/0x2e0
>  [<ffffffff8026cf3a>] lock_acquire+0x9a/0xe0
>  [<ffffffff8040e615>] blk_put_request+0x25/0x60
>  [<ffffffff806ab973>] _spin_lock_irqsave+0x43/0x90
>  [<ffffffff8040e615>] blk_put_request+0x25/0x60
>  [<ffffffff8040e615>] blk_put_request+0x25/0x60
>  [<ffffffff80520a94>] sg_finish_rem_req+0xa4/0x100
>  [<ffffffff805221b8>] sg_rq_end_io+0x278/0x2e0
>  [<ffffffff8040e2a1>] end_that_request_last+0x61/0x260
>  [<ffffffff8040e508>] blk_end_io+0x68/0xa0
>  [<ffffffff80508181>] scsi_end_request+0x41/0xd0
>  [<ffffffff80508870>] scsi_io_completion+0x130/0x470
>  [<ffffffff80413405>] blk_done_softirq+0x75/0x90
>  [<ffffffff802488ab>] __do_softirq+0x9b/0x180
>  [<ffffffff80213df3>] native_sched_clock+0x13/0x70
>  [<ffffffff8020d6ec>] call_softirq+0x1c/0x30
>  [<ffffffff8020f175>] do_softirq+0x65/0xa0
>  [<ffffffff80248345>] irq_exit+0xa5/0xb0
>  [<ffffffff8020f467>] do_IRQ+0x107/0x1d0
>  [<ffffffff8020c7fb>] ret_from_intr+0x0/0xf
>  <EOI>  [<ffffffff80214ba6>] mwait_idle+0x56/0x60
>  [<ffffffff80214b9d>] mwait_idle+0x4d/0x60
>  [<ffffffff8020b353>] cpu_idle+0x63/0xc0

Thanks for the update.

Rafael