[SCSI] zfcp: verify for correct rport state before scanning for SCSI devs

Prevent a SCSI target scan for a rport which have turned invalid
in the meantime.
Signed-off-by: NSwen Schillig <swen@vnet.ibm.com>
Signed-off-by: NChristof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

drivers/s390/scsi/zfcp_erp.c

@@ -1186,7 +1186,9 @@ static void zfcp_erp_scsi_scan(struct work_struct *work)
 		container_of(work, struct zfcp_erp_add_work, work);
 	struct zfcp_unit *unit = p->unit;
 	struct fc_rport *rport = unit->port->rport;
-	scsi_scan_target(&rport->dev, 0, rport->scsi_target_id,
+
+	if (rport && rport->port_state == FC_PORTSTATE_ONLINE)
+		scsi_scan_target(&rport->dev, 0, rport->scsi_target_id,
 			 scsilun_to_int((struct scsi_lun *)&unit->fcp_lun), 0);
 	atomic_clear_mask(ZFCP_STATUS_UNIT_SCSI_WORK_PENDING, &unit->status);
 	zfcp_unit_put(unit);