2 files changed, 50 insertions, 2 deletions

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 86c10cc751e..124b6f111cc 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -5797,6 +5797,22 @@ static void fill_result_tf(struct ata_queued_cmd *qc)
 	ap->ops->tf_read(ap, &qc->result_tf);
 }
 
+static void ata_verify_xfer(struct ata_queued_cmd *qc)
+{
+	struct ata_device *dev = qc->dev;
+
+	if (ata_tag_internal(qc->tag))
+		return;
+
+	if (ata_is_nodata(qc->tf.protocol))
+		return;
+
+	if ((dev->mwdma_mask || dev->udma_mask) && ata_is_pio(qc->tf.protocol))
+		return;
+
+	dev->flags &= ~ATA_DFLAG_DUBIOUS_XFER;
+}
+
 /**
  *	ata_qc_complete - Complete an active ATA command
  *	@qc: Command to complete
@@ -5868,6 +5884,9 @@ void ata_qc_complete(struct ata_queued_cmd *qc)
 			break;
 		}
 
+		if (unlikely(dev->flags & ATA_DFLAG_DUBIOUS_XFER))
+			ata_verify_xfer(qc);
+
 		__ata_qc_complete(qc);
 	} else {
 		if (qc->flags & ATA_QCFLAG_EH_SCHEDULED)
diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index 7d766ada7a5..359a5ace847 100644
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -456,9 +456,20 @@ void ata_scsi_error(struct Scsi_Host *host)
 		spin_lock_irqsave(ap->lock, flags);
 
 		__ata_port_for_each_link(link, ap) {
+			struct ata_eh_context *ehc = &link->eh_context;
+			struct ata_device *dev;
+
 			memset(&link->eh_context, 0, sizeof(link->eh_context));
 			link->eh_context.i = link->eh_info;
 			memset(&link->eh_info, 0, sizeof(link->eh_info));
+
+			ata_link_for_each_dev(dev, link) {
+				int devno = dev->devno;
+
+				ehc->saved_xfer_mode[devno] = dev->xfer_mode;
+				if (ata_ncq_enabled(dev))
+					ehc->saved_ncq_enabled |= 1 << devno;
+			}
 		}
 
 		ap->pflags |= ATA_PFLAG_EH_IN_PROGRESS;
@@ -2376,11 +2387,27 @@ static int ata_eh_revalidate_and_attach(struct ata_link *link,
 int ata_set_mode(struct ata_link *link, struct ata_device **r_failed_dev)
 {
 	struct ata_port *ap = link->ap;
+	struct ata_device *dev;
+	int rc;
 
 	/* has private set_mode? */
 	if (ap->ops->set_mode)
-		return ap->ops->set_mode(link, r_failed_dev);
-	return ata_do_set_mode(link, r_failed_dev);
+		rc = ap->ops->set_mode(link, r_failed_dev);
+	else
+		rc = ata_do_set_mode(link, r_failed_dev);
+
+	/* if transfer mode has changed, set DUBIOUS_XFER on device */
+	ata_link_for_each_dev(dev, link) {
+		struct ata_eh_context *ehc = &link->eh_context;
+		u8 saved_xfer_mode = ehc->saved_xfer_mode[dev->devno];
+		u8 saved_ncq = !!(ehc->saved_ncq_enabled & (1 << dev->devno));
+
+		if (dev->xfer_mode != saved_xfer_mode ||
+		    ata_ncq_enabled(dev) != saved_ncq)
+			dev->flags |= ATA_DFLAG_DUBIOUS_XFER;
+	}
+
+	return rc;
 }
 
 static int ata_link_nr_enabled(struct ata_link *link)
@@ -2441,6 +2468,8 @@ static int ata_eh_schedule_probe(struct ata_device *dev)
 	ata_dev_init(dev);
 	ehc->did_probe_mask |= (1 << dev->devno);
 	ehc->i.action |= ATA_EH_SOFTRESET;
+	ehc->saved_xfer_mode[dev->devno] = 0;
+	ehc->saved_ncq_enabled &= ~(1 << dev->devno);
 
 	return 1;
 }