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Subject: Re: [PATCH 2/3] scsi: fnic: Stop setting scsi_cmnd.tag
To:     John Garry <john.garry@huawei.com>, satishkh@cisco.com,
        sebaddel@cisco.com, kartilak@cisco.com, jejb@linux.ibm.com,
        martin.petersen@oracle.com
Cc:     linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org,
        hare@suse.de, hch@lst.de
References: <1628862553-179450-1-git-send-email-john.garry@huawei.com>
 <1628862553-179450-3-git-send-email-john.garry@huawei.com>
From:   Bart Van Assche <bvanassche@acm.org>
Message-ID: <3e5d1bd4-cee9-7fd0-93a4-58d808e198f6@acm.org>
Date:   Fri, 13 Aug 2021 20:17:45 -0700
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On 8/13/21 6:49 AM, John Garry wrote:
> It is never read. Setting it and the request tag seems dodgy
> anyway.

This is done because there is code in the SCSI error handler that may
allocate a SCSI command without allocating a tag. See also
scsi_ioctl_reset().

> ---
>  drivers/scsi/fnic/fnic_scsi.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/scsi/fnic/fnic_scsi.c b/drivers/scsi/fnic/fnic_scsi.c
> index 0f9cedf78872..f8afbfb468dc 100644
> --- a/drivers/scsi/fnic/fnic_scsi.c
> +++ b/drivers/scsi/fnic/fnic_scsi.c
> @@ -2213,7 +2213,7 @@ fnic_scsi_host_start_tag(struct fnic *fnic, struct scsi_cmnd *sc)
>  	if (IS_ERR(dummy))
>  		return SCSI_NO_TAG;
>  
> -	sc->tag = rq->tag = dummy->tag;
> +	rq->tag = dummy->tag;
>  	sc->host_scribble = (unsigned char *)dummy;

Reviewed-by: Bart Van Assche <bvanassche@acm.org>