Re: [PATCH v5 0/7] libsas and drivers: NCQ error handling

[Niklas Cassel]

On Wed, Oct 05, 2022 at 09:53:52AM +0100, John Garry wrote:
> On 04/10/2022 15:04, John Garry wrote:
> 
> Hi Niklas,
> 
> Could you try a change like this on top:
> 
> void sas_ata_device_link_abort(struct domain_device *device, bool
> force_reset)
> {
> 	struct ata_port *ap = device->sata_dev.ap;
> 	struct ata_link *link = &ap->link;
> 
> +	device->sata_dev.fis[2] = ATA_ERR | ATA_DRDY;
> +	device->sata_dev.fis[3] = 0x04;
> 
> 	link->eh_info.err_mask |= AC_ERR_DEV;
> 	if (force_reset)
> 		link->eh_info.action |= ATA_EH_RESET;
> 	ata_link_abort(link);
> }
> EXPORT_SYMBOL_GPL(sas_ata_device_link_abort);
> 
> I tried it myself and it looked to work ok, except I have a problem with my
> arm64 system in that the read log ext times-out and all TF show "device
> error", like:

Do you know why it fails to read the log?
Can you read the NCQ Command Error log using ATA16 passthrough commands?

sudo sg_sat_read_gplog -d --log=0x10 /dev/sdc

The first byte is the last NCQ tag (in hex) that failed.


I tried your patch, and it looks good:

[ 6656.228131] ata5.00: exception Emask 0x0 SAct 0x460000 SErr 0x0 action 0x0
[ 6656.252759] ata5.00: failed command: WRITE FPDMA QUEUED
[ 6656.271554] ata5.00: cmd 61/00:00:00:d8:8a/04:00:ce:03:00/40 tag 17 ncq dma 524288 out
                        res 41/04:00:00:00:00/00:00:00:00:00/00 Emask 0x1 (device error)
[ 6656.309308] ata5.00: status: { DRDY ERR }
[ 6656.316403] ata5.00: error: { ABRT }
[ 6656.322300] ata5.00: failed command: WRITE FPDMA QUEUED
[ 6656.330871] ata5.00: cmd 61/00:00:00:dc:8a/04:00:ce:03:00/40 tag 18 ncq dma 524288 out
                        res 41/04:00:00:00:00/00:00:00:00:00/00 Emask 0x1 (device error)
[ 6656.356295] ata5.00: status: { DRDY ERR }
[ 6656.362931] ata5.00: error: { ABRT }
[ 6656.368897] ata5.00: failed command: WRITE FPDMA QUEUED
[ 6656.377471] ata5.00: cmd 61/00:00:00:d4:8a/04:00:ce:03:00/40 tag 22 ncq dma 524288 out
                        res 43/04:00:ff:d7:8a/00:00:ce:03:00/40 Emask 0x400 (NCQ error) <F>
[ 6656.403149] ata5.00: status: { DRDY SENSE ERR }
[ 6656.410624] ata5.00: error: { ABRT }

However, since this is a change from the existing behavior of this driver,
this could go as a separate patch, and does not need to delay this series.



I also think that we should do a similar patch for sas_ata_task_done():

diff --git a/drivers/scsi/libsas/sas_ata.c b/drivers/scsi/libsas/sas_ata.c
index d35c9296f738..648d0693ceee 100644
--- a/drivers/scsi/libsas/sas_ata.c
+++ b/drivers/scsi/libsas/sas_ata.c
@@ -140,7 +140,7 @@ static void sas_ata_task_done(struct sas_task *task)
                        }
 
                        dev->sata_dev.fis[3] = 0x04; /* status err */
-                       dev->sata_dev.fis[2] = ATA_ERR;
+                       dev->sata_dev.fis[2] = ATA_ERR | ATA_DRDY;
                }
        }

To avoid all SAS errors from being reported as HSM errors.


Kind regards,
Niklas