Re: [PATCH 1/2] [PATCH v1 1/2] libata: fix reading concurrent positioning ranges log

[Damien Le Moal <damien.lemoal@opensource.wdc.com>]

On 6/1/22 02:50, Tyler Erickson wrote:
> From: Tyler Erickson <tyler.j.erickson@seagate.com>
> 
> The concurrent positioning ranges log is not a fixed size and may depend
> on how many ranges are supported by the device. This patch uses the size
> reported in the GPL directory to determine the number of pages supported
> by the device before attempting to read this log page.
> 
> Also fixing the page length in the SCSI translation for the concurrent
> positioning ranges VPD page.
> 
> This resolves this error from the dmesg output:
>     ata6.00: Read log 0x47 page 0x00 failed, Emask 0x1
> 
> Signed-off-by: Tyler Erickson <tyler.j.erickson@seagate.com>
> Reviewed-by: Muhammad Ahmad <muhammad.ahmad@seagate.com>
> Tested-by: Michael English <michael.english@seagate.com>

This needs a Fixes tag and cc stable.

> 
> diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
> index ca64837641be..3d57fa84e2be 100644
> --- a/drivers/ata/libata-core.c
> +++ b/drivers/ata/libata-core.c
> @@ -2003,16 +2003,16 @@ unsigned int ata_read_log_page(struct ata_device *dev, u8 log,
>  	return err_mask;
>  }
>  
> -static bool ata_log_supported(struct ata_device *dev, u8 log)
> +static int ata_log_supported(struct ata_device *dev, u8 log)
>  {
>  	struct ata_port *ap = dev->link->ap;
>  
>  	if (dev->horkage & ATA_HORKAGE_NO_LOG_DIR)
> -		return false;
> +		return 0;
>  
>  	if (ata_read_log_page(dev, ATA_LOG_DIRECTORY, 0, ap->sector_buf, 1))
> -		return false;
> -	return get_unaligned_le16(&ap->sector_buf[log * 2]) ? true : false;
> +		return 0;
> +	return get_unaligned_le16(&ap->sector_buf[log * 2]);
>  }
>  
>  static bool ata_identify_page_supported(struct ata_device *dev, u8 page)
> @@ -2448,15 +2448,20 @@ static void ata_dev_config_cpr(struct ata_device *dev)
>  	struct ata_cpr_log *cpr_log = NULL;
>  	u8 *desc, *buf = NULL;
>  
> -	if (ata_id_major_version(dev->id) < 11 ||
> -	    !ata_log_supported(dev, ATA_LOG_CONCURRENT_POSITIONING_RANGES))
> +	if (ata_id_major_version(dev->id) < 11)
> +		goto out;> +
> +	buf_len = ata_log_supported(dev, ATA_LOG_CONCURRENT_POSITIONING_RANGES);
> +	if (buf_len == 0)
>  		goto out;
>  
>  	/*
>  	 * Read the concurrent positioning ranges log (0x47). We can have at
> -	 * most 255 32B range descriptors plus a 64B header.
> +	 * most 255 32B range descriptors plus a 64B header. This log varies in
> +	 * size, so use the size reported in the GPL directory. Reading beyond
> +	 * the supported length will result in an error.
>  	 */
> -	buf_len = (64 + 255 * 32 + 511) & ~511;
> +	buf_len <<= 9;
>  	buf = kzalloc(buf_len, GFP_KERNEL);
>  	if (!buf)
>  		goto out;
> diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
> index 06c9d90238d9..0ea9c3115529 100644
> --- a/drivers/ata/libata-scsi.c
> +++ b/drivers/ata/libata-scsi.c
> @@ -2101,7 +2101,7 @@ static unsigned int ata_scsiop_inq_b9(struct ata_scsi_args *args, u8 *rbuf)
>  
>  	/* SCSI Concurrent Positioning Ranges VPD page: SBC-5 rev 1 or later */
>  	rbuf[1] = 0xb9;
> -	put_unaligned_be16(64 + (int)cpr_log->nr_cpr * 32 - 4, &rbuf[3]);
> +	put_unaligned_be16(64 + (int)cpr_log->nr_cpr * 32 - 4, &rbuf[2]);
>  
>  	for (i = 0; i < cpr_log->nr_cpr; i++, desc += 32) {
>  		desc[0] = cpr_log->cpr[i].num;

This scsi hunk needs to be a different patch with a fixes tag and cc stable.


-- 
Damien Le Moal
Western Digital Research