Petitboot: Linux in the Bootloader
Back in 2014 Jeremy Kerr gave a talk at LCA Perth about a new Linux based bootloader and its potential for server applications. A few years later and that potential has now become a reality as Petitboot is the primary bootloader for every OpenPOWER computer sold today, from the first POWER8 S812L server in 2014 to the POWER9 AC922 server that makes up the "Summit" and "Sierra" supercomputers that took out 1st and 3rd place in the Top500 last June. Based on popular open source tools like Buildroot and Busybox and using kexec as its booting mechanism gives Petitboot flexibility not only among OpenPOWER vendors and interested developers but makes it just as relevant on x86 and ARM, and has even found adoption outside of the POWER architecture. In this talk we will cover the Petitboot bootloader; what it is, how it works, the positives and the challenges of delivering an open source bootloader, how it fits in with the current bootloader ecosystem, and where we see Petitboot going in the future.