Future Challenges of the Genode project

This document compiles various ideas to pursue in the context of Genode. It is meant as source of inspiration for individuals who are interested in getting involved with the project and for students who want to base their student research projects on Genode.

Applications and library infrastructure
Application frameworks and runtime environments
Device drivers
System management

Applications and library infrastructure

VNC server implementing Genode's framebuffer session interface

With Input and Framebuffer, Genode provides two low-level interfaces used by interactive applications. For example, the Nitpicker GUI server uses these interfaces as a client and, in turn, exports multiple virtual Framebuffer and Input interfaces to its clients. This enables a highly modular use of applications such as the nesting of GUIs. By implementing the Framebuffer and Input interfaces with a VNC server implementation, all graphical workloads of Genode would become available over the network. One immediate application of this implementation is the remote testing of graphical Genode applications running on a headless server.

Interfacing with the SAFE network

The SAFE network is an attempt to fix many shortcomings of the internet - in particular with respect to privacy and freedom - at an architectural level. It is a peer-to-peer communication and storage network that does not depend on single point of failure or control. It is intriguing to explore the opportunity of integrating support for the SAFE network not merely as an application but integrated in the operating system, i.e., in the form of Genode components or a set of Genode VFS plugins.

Interactive sound switchbox based on Genode's Audio_out session interface

Since version 10.05, Genode features a highly flexible configuration concept that allows the arbitrary routing of session requests throughout the hierarchic process structure. Even though primarily designed for expressing mandatory-access control rules, the concept scales far beyond this use case. For example, it can be used to run an arbitrary number of processes implementing the same interface and connecting the different interface implementations. One special case of this scenario is a chain of audio filters with each using the Audio_out session interface for both roles client and server. Combined with the Nitpicker GUI server and Genode's support for real-time priorities, this base techniques enable the creation of flexible audio mixer / switchboard applications, which require dedicated frameworks (e.g., Jack audio) on traditional operating systems. The goal of this project is to create a showcase implementation demonstrating the feasibility for creating high-quality audio applications on Genode. Furthermore, we wish for feedback regarding the current design of our bulk streaming interface when used for low-latency applications.

Graphical on-target IPC tracing tool using Qt

Analysing the interaction of components of a multi-server operating system such as Genode is important to discover bottlenecks of the system and for debugging highly complex usage scenarios involving many processes. Currently, Genode handles this problem with two approaches. First, Genode's recursive structure enables the integration of a subsystem in a basic OS setup featuring only those drivers and components used for the particular subsystem. After the successful integration of such a subsystem, it can be embedded into a far more complex application scenario without any changes. With this approach, the subject to analyse can be kept at a reasonable level at integration time. For debugging purposes, the current approach is using the debugging facilities of the respective base platforms (e.g., using GDB on Linux, the Fiasco kernel debugger, the OKL4 kernel debugger).

However, in many cases, bottlenecks do not occur when integrating individual sub systems but after integrating multiple of such subsystems into a large application scenario. For such scenarios, existing debugging methodologies do not scale. A tool is desired that is able to capture the relationships between processes of a potentially large process hierarchy, to display communication and control flows between those processes, and to visualize the interaction of threads with the kernel's scheduler.

Since Qt is available natively on Genode, the creation of both offline and on-target analysis tools has become feasible. The first step of this project is creating an interactive on-target tool, that displays the interaction of communicating threads as captured on the running system. The tool should work on a selected kernel that provides a facility for tracing IPC messages.

The underlying light-weight tracing infrastructure is already in place. The Qt-based tracing tools would complement this infrastructure with an interactive front end.

Ports of popular software

Genode features a ports mechanism to cleanly integrate 3rd-party software. Thanks to the C runtime, the flexible per-component VFS, the standard C++ library, and the Noux runtime (for UNIX software), porting software to Genode is relatively straight forward. The porting guide explains the typical steps. A wish list of software that we'd like to have available on Genode is available at https://usr.sysret.de/jws/genode/porting_wishlist.html.

Native Open-Street-Maps (OSM) client

When using Sculpt OS, we regularly need to spawn a fully fledged web browser in a virtual machine for using OSM or Google maps. The goal of this project would be a native component that makes maps functionality directly available on Genode, alleviating the urge to reach for a SaaS product. The work would include a review of existing OSM clients regarding their feature sets and the feasibility of porting them to Genode. Depending on the outcome of this review, an existing application could be ported or a new component could be developed, e.g., leveraging Genode's Qt support.

Application frameworks and runtime environments


OpenJDK is the reference implementation of the Java programming language and hosts an enormous ecosystem of application software.

Since version 19.02, Genode features a port of OpenJDK that allows the use of Java for networking applications.

The next step would be the creation of Genode-specific native classes that bridge the gap between the Java world and Genode, in particular the glue code to run graphical applications as clients of Genode's GUI server. Since OpenJDK has been ported to numerous platforms (such as Haiku), there exists a comforting number of implementations that can be taken as reference.

Android's ART VM natively on Genode

ART is a Java virtual machine that is used for executing applications on Android. By running ART directly on Genode, the Linux kernel could be removed from the trusted computing base of Android, facilitating the use of this mobile OS in high-assurance settings.

Go language runtime

Go is a popular language in particular for web applications. In the past, there were numerous attempts to make the Go runtime available on Genode but so far, none of those undertakings have landed in the official Genode source tree. To goal of this project is the hosting of Go-written applications - in particular networking applications - as Genode components. The topic comprises work on the tool-chain and build-system integration, the porting the runtime libraries, and the glue between the Go and Genode environments.

Combination of CAmkES with Genode

CAmkES is a component framework for seL4. In contrast to Genode, which is a dynamic system, CAmkES-based systems are defined at design time and remain fixed at runtime. Hence, CAmkES and Genode can be seen as the opposite ends of component-based used-land architectures. The goal of this project is to build a bridge between both projects with the potential to cross-pollinate the respective communities. Among the principal approaches are embedding of a single CAmkES component as a Genode component (e.g., an individual device driver), the hosting of a dynamic Genode system as a component within a CAmkES system, or the hosting of a CAmkES system composition as a Genode subsystem.

Runtime for the D programming language

The D systems programming language was designed to overcome many gripes that exists with C++. In particular, it introduces a sane syntax for meta programming, supports unit tests, and contract-based programming. These features make D a compelling language to explore when implementing OS components. Even though D is a compiled language, it comes with a runtime providing support for exception handling and garbage collection. The goal of the project is to explore the use of D for Genode programs, porting the runtime to Genode, adapting the Genode build system to accommodate D programs, and interfacing D programs with other Genode components written in C++.

Using Haskell as systems-development language

The goal of this project is the application of functional programming i.e., Haskell, for the implementation of low-level Genode components. Implementing critical functionalities in such a high-level language instead of a classical systems language such as C or C++ would pave the way towards analyzing such components with formal methods.

The use of Haskell for systems development was pioneered by the House Project. A more recent development is HalVM - a light-weight OS runtime for Xen that is based on Haskell.

Xlib compatibility

Developments like Wayland notwithstanding, most application software on GNU/Linux systems is built on top of the Xlib programming interface. However, only a few parts of this wide interface are actually used today. I.e., modern applications generally deal with pixel buffers instead of relying on graphical drawing primitives of the X protocol. Hence, it seems feasible to reimplement the most important parts of the Xlib interface to target Genode's native GUI interfaces (nitpicker) directly. This would allow us to port popular application software to Sculpt OS without changing the application code.

Bump-in-the-wire components for visualizing session interfaces

Genode's session interfaces bear the potential for monitoring and visualizing their use by plugging a graphical application in-between any two components. For example, by intercepting block requests issued by a block-session client to a block-device driver, such a bump-in-the-wire component could visualize the access patterns of a block device. Similar ideas could be pursued for other session interfaces, like the audio-out (sound visualization) or NIC session (live visualization of network communication).

The visualization of system behavior would offer valuable insights, e.g., new opportunities for optimization. But more importantly, they would be extremely fun to play with.


VirtualBox on top of KVM on Linux

Genode's version of VirtualBox replaces the original in-kernel VirtualBox hypervisor by the virtualization mechanism of the NOVA hypervisor or the Muen separation kernel. Those mechanisms look very similar the KVM interface of the Linux kernel. It should in principle be possible to re-target Genode's version of VirtualBox to KVM. This way, VirtualBox and Qemu/KVM-based virtual machines could co-exist on the same system, which is normally not possible. Also, complex Genode scenarios (like Turmvilla) could be prototyped on GNU/Linux.

Xen as kernel for Genode

Using Xen as kernel for Genode would clear the way to remove the overly complex Linux OS from the trusted computing base of Xen guests OSes.

Xen is a hypervisor that can host multiple virtual machines on one physical machine. For driving physical devices and for virtual-machine management, Xen relies on a privileged guest OS called Dom0. Currently, Linux is the predominant choice to be used as Dom0, which implicates a trusted computing base of millions of lines of code for the other guest OSes.

Even though Xen was designed as hypervisor, a thorough analysis done by Julian Stecklina concludes that Xen qualifies well as a kernel for Genode. For example, Julian implemented a version of Genode's IPC framework that utilizes Xen's communication mechanisms (event channels and shared memory).

Genode as virtualization layer for Qubes OS

Qubes OS is a desktop operating system that follows the principle of security through compartmentalization. In spirit, it is closely related to Genode. In contrast Genode's clean-slate approach of building a fine-grained multi-component system, Qubes employs Xen-based virtual machines as sandboxing mechanism. In version 3.0, Qubes introduced a Hypervisor Abstraction Layer, which decouples Qubes from the underlying virtualization platform. This exploration project pursues the goal of replacing Xen by Genode as virtualization layer for Qubes.


As we use Qemu as primary testing platform for most of the kernels, a port of Qemu to Genode is needed in order to move our regular work flows to Genode as development platform. The basic prerequisites namely libSDL and a C runtime are already available such that this porting work seems to be feasible. In our context, the ia32, amd64, and ARM platforms are of most interest. Note that the project does not have the immediate goal of using hardware-based virtualization. However, if there is interest, the project bears the opportunity to explore the provisioning of the KVM interface based on Genode's VFS plugin concept.

Hardware-accelerated graphics for virtual machines

In Genode 17.08, we introduced a GPU multiplexer for Intel Broadwell along with support for Mesa-based 3D-accelerated applications. While designing Genode's GPU-session interface, we also aimed at supporting the hardware-accelerated graphics for Genode's virtual machine monitors like VirtualBox or Seoul, but until now, we did not took the practical steps of implementing a virtual GPU device model.

The goal of this project is the offering of a virtual GPU to a Linux guest OS running on top of Genode's existing virtualization and driver infrastructure.

Device drivers

Sound on the Raspberry Pi

The goal of this project is a component that uses the Raspberry Pi's PWM device to implement Genode's audio-out-session interface. Since Genode's version of libSDL already supports this interface as audio backend, the new driver will make the sound of all SDL-based games available on the Raspberry Pi.

Data Plane Development Kit (DPDK)

Genode utilizes the network device drivers of the iPXE project, which perform reasonably well for everyday use cases but are obviously not designated for high-performance networking. The DPDK is a vendor-supported suite of network device drivers that is specifically developed for high-performance applications. It presents an attractive alternative to iPXE-based drivers. This project has the goal to make DPDK drivers available as a Genode component.


Microkernelizing Linux

Thanks to Genode's generic interfaces for I/O access as provided by core, all Genode device drivers including drivers ported from Linux and gPXE can be executed as user-level components on all supported microkernels. However, so far, we have not enabled the use of these device drivers on Linux as base platform. The goal of this project is the systematic replacement of in-kernel Linux device drivers by Genode processes running in user space, effectively reducing the Linux kernel to a runtime for Genode's core process. But moving drivers to Genode processes is just the beginning. By employing further Genode functionality such as its native GUI, lwIP, and Noux, many protocol stacks can effectively be removed from the Linux kernel.

In 2018, Johannes Kliemann pursued this topic to a state where Genode could be used as init process atop a customized Linux kernel. His work included the execution of Genode's regular device drivers for VESA and PS/2 as regular Genode components so that Genode's interactive demo scenario ran happily on a laptop. At this time, however, only parts of his results were merged into Genode's mainline.

The goal of this project is to follow up on Johannes' work, bring the remaining parts into shape for the inclusion into Genode, and address outstanding topics, in particular the handling of DMA by user-level device drivers. Further down the road, it would be tempting to explore the use of seccomp as sandboxing mechanism for Genode on Linux and the improvement of the Linux-specific implementation of Genode's object-capability model.

Support for the HelenOS/SPARTAN kernel

HelenOS is a microkernel-based multi-server OS developed at the university of Prague. It is based on the SPARTAN microkernel, which runs on a wide variety of CPU architectures including Sparc, MIPS, and PowerPC. This broad platform support makes SPARTAN an interesting kernel to look at alone. But a further motivation is the fact that SPARTAN does not follow the classical L4 road, providing a kernel API that comes with an own terminology and different kernel primitives. This makes the mapping of SPARTAN's kernel API to Genode a challenging endeavour and would provide us with feedback regarding the universality of Genode's internal interfaces. Finally, this project has the potential to ignite a further collaboration between the HelenOS and Genode communities.

Support for the XNU kernel (Darwin)

XNU is the kernel used by Darwin and Mac OS X. It is derived from the MACH microkernel and extended with a UNIX-like syscall API. Because the kernel is used for Mac OS X, it could represent an industry-strength base platform for Genode supporting all CPU features as used by Mac OS X.

Genode on the Librem5 phone hardware

Even though there exists a great variety of ARM-based SoCs, Genode primarily focuses on the NXP i.MX family because it is - in contrast to most SoCs in the consumer space - very liberal in terms of good-quality public documentation and reference code, and it scales from industrial to end-user-facing use cases (multi-media).

The Librem5 project - with its mission to build a trustworthy mobile phone - has chosen the i.MX family as the basis for their product for likely the same reasons that attract us.

To goal of this work is bringing Genode to the Librem5 hardware. For the Librem5 project, Genode could pave the ground towards new use cases like high-security markets where a regular Linux-based OS would not be accepted. For the Genode community, the Librem5 hardware could become an attractive mobile platform for everyday use, similar to how we developers use our Genode-based Sculpt OS on our laptops.

System management

Remote management of Sculpt OS via Puppet

Puppet is a software-configuration management tool for administering a large amount of machines from one central place. Genode's Sculpt OS lends itself to such an approach of remote configuration management by the means of the "config" file system (for configuring components and deployments) and the "report" file system (for obtaining the runtime state of components). The project would explore the application of the Puppet approach and tools to Sculpt OS.


De-privileging the VESA graphics driver

The VESA graphics driver executes the graphics initialization code provided by the graphics card via an x86 emulator. To initialize a graphics mode, this code needs to access device hardware. Currently, we permit access to all device registers requested by the graphics-card's code. These devices include the system timer, the PCI configuration registers, and the interrupt controller, which are critical for the proper operating of the kernel. The goal of this work is to restrict the permissions of the VESA driver to a minimum by virtualizing all devices but the actual graphics card.