Expected behaviour for device hang

[David.Darrington at hgst.com]

What is the expected behaviour of the driver if a device hangs? If  a 
device stops processing commands, the commands will eventually timeout, 
which is handled in 'nvme_kthread' with a call to 'nvme_cancel_ios'. 
However, this is not calling bio_completion. Every second the cycle 
repeats, cancelling the same I/Os and syslog fills up with the message 
'Cancelling I/O xx'. I was expecting that the ios that timeout would be 
completed as failed and freed.

Is there something that is still TBD, or am I just missing something.

Thanks,
Dave