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Date:   Mon, 3 Apr 2023 01:18:03 -0400
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Reply-To: dgilbert@interlog.com
Subject: Re: [PATCH v3 06/11] scsi: scsi_debug: Dynamically allocate
 sdebug_queued_cmd
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To:     John Garry <john.g.garry@oracle.com>, jejb@linux.ibm.com,
        martin.petersen@oracle.com
Cc:     linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org,
        bvanassche@acm.org
References: <20230327074310.1862889-1-john.g.garry@oracle.com>
 <20230327074310.1862889-7-john.g.garry@oracle.com>
From:   Douglas Gilbert <dgilbert@interlog.com>
In-Reply-To: <20230327074310.1862889-7-john.g.garry@oracle.com>
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On 2023-03-27 03:43, John Garry wrote:
> Eventually we will drop the sdebug_queue struct as it is not really
> required, so start with making the sdebug_queued_cmd dynamically allocated
> for the lifetime of the scsi_cmnd in the driver.
> 
> As an interim measure, make sdebug_queued_cmd.sd_dp a pointer to struct
> sdebug_defer. Also keep a value of the index allocated in
> sdebug_queued_cmd.qc_arr in struct sdebug_queued_cmd.
> 
> To deal with an races in accessing the scsi cmnd allocated struct
> sdebug_queued_cmd, add a spinlock for the scsi command in its priv area.
> Races may be between scheduling a command for completion, aborting a
> command, and the command actually completing and freeing the struct
> sdebug_queued_cmd.
> 
> Signed-off-by: John Garry <john.g.garry@oracle.com>
Acked-by: Douglas Gilbert <dgilbert@interlog.com>

Thanks.