(In reply to Stefan Hundhammer from comment #2) > https://github.com/yast/yast-s390/blob/master/src/lib/y2s390/dasds_reader. > rb#L172-L176 > > > def use_diag?(dasd) > > diag_file = "/sys/#{dasd.sysfs_id}/device/use_diag" > > use_diag = Yast::SCR.Read(Yast.path(".target.string"), diag_file) if File.exist?(diag_file) > > use_diag.to_i == 1 > > end > > If the file does not exist, "use_diag" will remain nil, and "use_diag.to_i" > will throw a nil.NilClass exception because "use_diag.to_i" will evaluate to > "nil.to_i". This was already expected and it will be evaluated to 0, which is not enabled