diff --git a/sys/bus/cam/scsi/scsi_sa.c b/sys/bus/cam/scsi/scsi_sa.c
--- a/sys/bus/cam/scsi/scsi_sa.c
+++ b/sys/bus/cam/scsi/scsi_sa.c
@@ -3267,6 +3267,7 @@
 
 	ccb = cam_periph_getccb(periph, 1);
 	Set_CCB_Type(ccb, SA_CCB_POLLED);
+	bzero(&loc, sizeof(loc));
 	scsi_read_position(&ccb->csio, 1, sadone, MSG_SIMPLE_Q_TAG,
 			   hard, &loc, SSD_FULL_SIZE, SCSIOP_TIMEOUT);
 	softc->dsreg = MTIO_DSREG_RBSY;