From mboxrd@z Thu Jan  1 00:00:00 1970
From: Bart Van Assche <bart.vanassche@sandisk.com>
Subject: Re: [PATCH 1/2] target: Fix LUN_RESET active I/O handling for
 ACK_KREF
Date: Tue, 12 Jan 2016 08:32:48 -0800
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To: Christoph Hellwig <hch@lst.de>, "Nicholas A. Bellinger" <nab@daterainc.com>
Cc: target-devel <target-devel@vger.kernel.org>, linux-scsi <linux-scsi@vger.kernel.org>, Quinn Tran <quinn.tran@qlogic.com>, Himanshu Madhani <himanshu.madhani@qlogic.com>, Sagi Grimberg <sagig@mellanox.com>, Hannes Reinecke <hare@suse.de>, Andy Grover <agrover@redhat.com>, Nicholas Bellinger <nab@linux-iscsi.org>

On 01/12/2016 07:20 AM, Christoph Hellwig wrote:
>> It also introduces SCF_ACK_KREF to determine when
>> transport_cmd_finish_abort() needs to drop the second
>> extra reference, ahead of calling target_put_sess_cmd()
>> for the final kref_put(&se_cmd->cmd_kref).
>
> It would be really useful to have all drivers follow that
> ACK KREF model instead of needing to deal with driver
> differences everywhere..

Hello Christoph,

How about eliminating the TARGET_SCF_ACK_KREF flag ? If a command would 
only be freed upon the last target_put_sess_cmd() call then I think that 
the check_stop_free() callback wouldn't have to call 
target_put_sess_cmd() and hence that the TARGET_SCF_ACK_KREF flag could 
be removed.

Bart.