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Subject: Re: [PATCH v6 4/6] scsi: sd: Allow max_sectors be capped at DMA
 optimal size limit
From:   "Martin K. Petersen" <martin.petersen@oracle.com>
Organization: Oracle Corporation
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References: <1657797329-98541-1-git-send-email-john.garry@huawei.com>
        <1657797329-98541-5-git-send-email-john.garry@huawei.com>
Date:   Mon, 18 Jul 2022 22:30:39 -0400
In-Reply-To: <1657797329-98541-5-git-send-email-john.garry@huawei.com> (John
        Garry's message of "Thu, 14 Jul 2022 19:15:27 +0800")
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John,

> diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
> index a1a2ac09066f..3eaee1f7aaca 100644
> --- a/drivers/scsi/sd.c
> +++ b/drivers/scsi/sd.c
> @@ -3296,6 +3296,8 @@ static int sd_revalidate_disk(struct gendisk *disk)
>  				      (sector_t)BLK_DEF_MAX_SECTORS);
>  	}
>  
> +	rw_max = min_not_zero(rw_max, sdp->host->opt_sectors);
> +
>  	/* Do not exceed controller limit */
>  	rw_max = min(rw_max, queue_max_hw_sectors(q));

I'm OK with this approach.

Acked-by: Martin K. Petersen <martin.petersen@oracle.com>

-- 
Martin K. Petersen	Oracle Linux Engineering