As a teaser for the upcoming release of the Genode OS Framework 9.05, the newly added support for the OKL4 kernel has been released to the project’s subversion repository. Genode is a framework for building custom microkernel-based operating systems using a capability-based architecture geared towards high security and robustness. Among the features of Genode are a custom GUI, a device driver kit, and native Qt4 support. From the ground up, it was laid out to be highly portable among different kernels.
OKL4 developed by Open Kernel Labs is a descendant of the Pistachio L4 kernel. In contrast to Pistachio, which sticks to the latest official L4 kernel API, OKL4 has a substantially modernized kernel API and is being shaped towards a capability-based kernel. The kernel is available on both commercial terms and as open-source software, whereas the commercial version is deployed on a wide range of embedded devices, in particular cell phones.
The article “Bringing the Genode OS Framework to the OKL4 kernel” describes the endeavour of exploring the OKL4 2.1 kernel and adapting Genode to this new execution environment. It provides in-depth technical information, but more importantly, it presents a useful methodology of approaching the challenge of bringing a complete user land to a new kernel.
With OKL4 having now become available as base platform for Genode, the Genode project reached an important milestone towards the goal to provide a common ground for developing applications, device drivers, and protocol stacks for microkernel platforms. With the framework, user-level components can now be conveniently developed and debugged on Linux, and deployed on three different microkernel platforms: L4ka::Pistachio, OKL4, and L4/Fiasco. More information about the use of Genode on OKL4 is available at the dedicated Genode-on-OKL4 Wiki page.