diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index 0b5d3a5..ee9b96d 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -1253,11 +1253,11 @@
 	unsigned long timeout = jiffies + (HZ * 5);
 
 	if (ap->flags & ATA_FLAG_SATA_RESET) {
-		scr_write(ap, SCR_CONTROL, 0x301); /* issue phy wake/reset */
-		scr_read(ap, SCR_STATUS);	/* dummy read; flush */
+		/* issue phy wake/reset */
+		scr_write_flush(ap, SCR_CONTROL, 0x301);
 		udelay(400);			/* FIXME: a guess */
 	}
-	scr_write(ap, SCR_CONTROL, 0x300);	/* issue phy wake/clear reset */
+	scr_write_flush(ap, SCR_CONTROL, 0x300); /* phy wake/clear reset */
 
 	/* wait for phy to become ready, if necessary */
 	do {
@@ -2539,7 +2539,7 @@
 	ata_sg_init_one(qc, cmd->sense_buffer, sizeof(cmd->sense_buffer));
 	qc->dma_dir = DMA_FROM_DEVICE;
 
-	memset(&qc->cdb, 0, sizeof(ap->cdb_len));
+	memset(&qc->cdb, 0, ap->cdb_len);
 	qc->cdb[0] = REQUEST_SENSE;
 	qc->cdb[4] = SCSI_SENSE_BUFFERSIZE;
 
@@ -2811,6 +2811,7 @@
 
 	/* call completion callback */
 	rc = qc->complete_fn(qc, drv_stat);
+	qc->flags &= ~ATA_QCFLAG_ACTIVE;
 
 	/* if callback indicates not to complete command (non-zero),
 	 * return immediately
@@ -3229,7 +3230,8 @@
 			struct ata_queued_cmd *qc;
 
 			qc = ata_qc_from_tag(ap, ap->active_tag);
-			if (qc && (!(qc->tf.ctl & ATA_NIEN)))
+			if (qc && (!(qc->tf.ctl & ATA_NIEN)) &&
+			    (qc->flags & ATA_QCFLAG_ACTIVE))
 				handled |= ata_host_intr(ap, qc);
 		}
 	}
diff --git a/drivers/scsi/libata-scsi.c b/drivers/scsi/libata-scsi.c
index 4c96df0..416ba67 100644
--- a/drivers/scsi/libata-scsi.c
+++ b/drivers/scsi/libata-scsi.c
@@ -347,7 +347,10 @@
 		 */
 		if ((dev->flags & ATA_DFLAG_LBA48) &&
 		    ((dev->flags & ATA_DFLAG_LOCK_SECTORS) == 0)) {
-			sdev->host->max_sectors = 2048;
+			/*
+			 * do not overwrite sdev->host->max_sectors, since
+			 * other drives on this host may not support LBA48
+			 */
 			blk_queue_max_sectors(sdev->request_queue, 2048);
 		}
 	}
diff --git a/drivers/scsi/sata_svw.c b/drivers/scsi/sata_svw.c
index 8d1a5d2..05075bd 100644
--- a/drivers/scsi/sata_svw.c
+++ b/drivers/scsi/sata_svw.c
@@ -395,7 +395,7 @@
 
 	/* Clear a magic bit in SCR1 according to Darwin, those help
 	 * some funky seagate drives (though so far, those were already
-	 * set by the firmware on the machines I had access to
+	 * set by the firmware on the machines I had access to)
 	 */
 	writel(readl(mmio_base + K2_SATA_SICR1_OFFSET) & ~0x00040000,
 	       mmio_base + K2_SATA_SICR1_OFFSET);
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 505160a..1f7e203 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -584,6 +584,13 @@
 	ap->ops->scr_write(ap, reg, val);
 }
 
+static inline void scr_write_flush(struct ata_port *ap, unsigned int reg, 
+				   u32 val)
+{
+	ap->ops->scr_write(ap, reg, val);
+	(void) ap->ops->scr_read(ap, reg);
+}
+
 static inline unsigned int sata_dev_present(struct ata_port *ap)
 {
 	return ((scr_read(ap, SCR_STATUS) & 0xf) == 0x3) ? 1 : 0;