The profiling tools in the kernel are changing at a fast pace. This talk is about the support for ARM and ARM64 architecture and the development of features for these architectures, namely the callchain unwinding. The presentation goes over: - the detailed description of the feature, - the methods used to do the callchain unwinding (fp, exidx, dwarf etc.), - the status of the on-going patches, - the remaining work to be done, - the links to patches, discussions on the mailing lists, - -if needed and if time allows- a demo of the feature.