Examples of video encoding methods and apparatus and video decoding methods and apparatus are described. An example method of video processing includes performing a conversion between a video and a bitstream of the video, wherein the bitstream includes one or more output layer sets comprising one or more video layers according to a format rule, wherein the format rule specifies that a non-scalable-nested supplemental enhancement information, SEI, message that includes information regarding hypothetical reference decoder, HRD, is applicable to all output layer sets that include same video layers as the bitstream.