---
title: "Unikraft OSS Roadmap 2022-2023"
tags: unikraft, community, roadmap, milestone
---

| Feature | Owner | Tech Lead | Priority |
|--------------------------------------------------------------------------|---------------------------------------|---------------------------------------|--------------|
| [Driver Probing Framework](#Driver-Probing-Framework) | [Răzvan Deaconescu](https://github.com/razvand) | [Michalis Pappas](https://github.com/michpappas) | medium |
| [Memory Tagging Extension](#Memory-Tagging-Extension) | [Hugo Lefeuvre](https://github.com/hlef) | [Michalis Pappas](https://github.com/michpappas) | medium |
| [ukcpuid](#ukcpuid) | [Răzvan Deaconescu](https://github.com/razvand) | [Simon Kuenzer](https://github.com/skuenzer) | medium |
| [Hardware Randomization](#Hardware-Randomization) | [Răzvan Deaconescu](https://github.com/razvand) | [Marc Rittinghaus](https://github.com/marcrittinghaus) | medium |
| [procfs Support](#procfs-Support) | [Răzvan Deaconescu](https://github.com/razvand) | [Simon Kuenzer](https://github.com/skuenzer) | medium |
| [Musl Support](#Musl-Support) | [Răzvan Deaconescu](https://github.com/razvand) | [Simon Kuenzer](https://github.com/skuenzer) | high |
| [libc Test Library](#libc-Test-Library) | [Răzvan Deaconescu](https://github.com/razvand) | [Simon Kuenzer](https://github.com/skuenzer) | medium |
| [ukstore (dynamic)](#ukstore-(dynamic)) | [Cezar Crăciunoiu](https://github.com/craciunoiuc) | [Simon Kuenzer](https://github.com/skuenzer) | high |
| [Memory Ballooning](#Memory-Ballooning) | [Cezar Crăciunoiu](https://github.com/craciunoiuc) | [Simon Kuenzer](https://github.com/skuenzer) | low |
| [Rust Support](#Rust-Support) | [Răzvan Deaconescu](https://github.com/razvand) | [Vlad Bădoiu](https://github.com/vladandrew) | high |
| [containerd integration](#containerd-integration) | [Alexander Jung](https://github.com/nderjung) | [Alexander Jung](https://github.com/nderjung) | high |
| [Memory Randomization](#Memory-Randomization) | [Hugo Lefeuvre](https://github.com/hlef) | [Marc Rittinghaus](https://github.com/marcrittinghaus) | medium |
| [Unit Tests for Internal Libraries](#Unit-Tests-for-Internal-Libraries) | [Răzvan Deaconescu](https://github.com/razvand) | [Library author](https://github.com/) | medium |
| [Code Conventions](#Code-Conventions) | [Răzvan Deaconescu](https://github.com/razvand) | [Marc Rittinghaus](https://github.com/marcrittinghaus) | high |
| [ELF Loader](#ELF-Loader) | [Răzvan Deaconescu](https://github.com/razvand) | [Simon Kuenzer](https://github.com/skuenzer) | high |
| [Unikraft Loader](#Unikraft-Loader) | [Răzvan Deaconescu](https://github.com/razvand) | [Simon Kuenzer](https://github.com/skuenzer) | medium |
| [Hyper-V Support](#Hyper-V-Support) | [Răzvan Deaconescu](https://github.com/razvand) | [Marc Rittingaus](https://github.com/) | medium |
| [VMware Support](#VMware-Support) | [Răzvan Deaconescu](https://github.com/razvand) | [Marc Rittingaus](https://github.com/) | medium |
| [Firecracker Support](#Firecracker-Support) | [Răzvan Deaconescu](https://github.com/razvand) | [Simon Kuenzer](https://github.com/skuenzer) | high |
| [Baremetal Support](#Baremetal-Support) | [Răzvan Deaconescu](https://github.com/razvand) | [Michalis Pappas](https://github.com/michpappas) | low |
| [Multiple Bootloaders](#Multiple-Bootloaders) | [Răzvan Deaconescu](https://github.com/razvand) | [Simon Kuenzer](https://github.com/skuenzer) | medium |
| [Platform Rearchitecting](#Platform-Rearchitecting) | [Michalis Pappas](https://github.com/michpappas) | [Simon Kuenzer](https://github.com/skuenzer) | high |
| [SMP-safe Unikraft Core](#SMP-safe-Unikraft-Core) | [Michalis Pappas](https://github.com/michpappas) | [Marc Rittingaus](https://github.com/) | medium |
| [SMP-safe Memory Allocation](#SMP-safe-Memory-Allocation) | [Michalis Pappas](https://github.com/michpappas) | [Hugo Lefeuvre](https://github.com/hlef) | medium-high |
| [POSIX mmap](#POSIX-mmap) | [Marc Rittinghaus](https://github.com/marcrittinghaus) | [Marc Rittinghaus](https://github.com/marcrittinghaus) | high |
| [W^X Support](#W^X-Support) | [Marc Rittinghaus](https://github.com/marcrittinghaus) | [Michalis Pappas](https://github.com/michpappas) | medium |
| [uknofault](#uknofault) | [Marc Rittinghaus](https://github.com/marcrittinghaus) | [Marc Rittinghaus](https://github.com/marcrittinghaus) | medium |
| [GDB Stub](#GDB-Stub) | [Marc Rittinghaus](https://github.com/marcrittinghaus) | [Marc Rittinghaus](https://github.com/marcrittinghaus) | medium |
| [Automated API Documentation](#Automated-API-Documentation) | [Alexander Jung](https://github.com/nderjung) | [Ștefan Jumărea](https://github.com/StefanJum) | medium-high |
| [Core Library READMEs](#Core-Library-READMEs) | [Alexander Jung](https://github.com/nderjung) | [Ștefan Jumărea](https://github.com/StefanJum) | medium-high |
| [Kernel Log Exporting](#Kernel-Log-Exporting) | [Răzvan Deaconescu](https://github.com/razvand) | [Marc Rittinghaus](https://github.com/marcrittinghaus) | medium |
| [Unikraft Packaging](#Unikraft-Packaging) | [Răzvan Deaconescu](https://github.com/razvand) | [Alexander Jung](https://github.com/nderjung) | medium |
| [RISC-V Support](#RISC-V-Support) | [Răzvan Deaconescu](https://github.com/razvand) | [Michalis Pappas](https://github.com/michpappas) | medium |
| [Driver Shim Layer](#Driver-Shim-Layer) | [Răzvan Deaconescu](https://github.com/razvand) | [Simon Kuenzer](https://github.com/skuenzer) | low |
| [Signal Reimplementation](#Signal-Reimplementation) | [Simon Kuenzer](https://github.com/skuenzer) | [Simon Kuenzer](https://github.com/skuenzer) | high |
| [ISR-Safe Code](#ISR-Safe-Code) | [Răzvan Deaconescu](https://github.com/razvand) | [Simon Kuenzer](https://github.com/skuenzer) | high |
| [Unikraft System Shutdown](#Unikraft-System-Shutdown) | [Simon Kuenzer](https://github.com/skuenzer) | [Simon Kuenzer](https://github.com/skuenzer) | high |

:::info
_copy-paste this and fill contents:_

## Template [template]

**Author**: Firstname Lastname
**Owner**: TODO
**Tech lead**: TODO
**Estimated duration**: TODO
**Priority**: TODO

**Rationale for topic relevance**

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**Summary of objectives**

- [Please fill in here]

**Prerequisites / dependencies**

- [Please fill in here]

**Notes**

- [Please fill in here]

:::

## Driver Probing Framework

**Author**: Michalis Pappas
**Owner**: Răzvan Deaconescu
**Tech lead**: Michalis Pappas
**Estimated duration**: 4 months
**Priority**: medium

**Rationale for topic relevance**

Register driver corresponding to device.
Probe for devices at boot or when connected.

**Notes**

- Implement using `ukbus`.

---

## Memory Tagging Extension

**Author**: Michalis Pappas
**Owner**: Hugo Lefeuvre
**Tech lead**: Michalis Pappas
**Estimated duration**: 2 weeks
**Priority**: medium

**Rationale for topic relevance**

Add support for [MTE](https://source.android.com/docs/security/test/memory-safety/arm-mte) (*Memory Tagging Extension*) to tag memory on ARM64.

**Notes**

- [PR available](https://github.com/unikraft/unikraft/pull/458), needs to be reviewed

---

## ukcpuid

**Author**: Răzvan Deaconescu
**Owner**: Răzvan Deaconescu
**Tech lead**: Simon Kuenzer
**Estimated duration**: 3 months
**Priority**: medium

**Rationale for topic relevance**

Query CPU features early in the boot process to use in later phases, such as when invoking hardware randomization.

**Summary of objectives**

- [ ] Provide arch-level API (`ukcpuid`)
- [ ] Add implementation for x86
- [ ] Add implementation for ARM

**Notes**

- [PR available](https://github.com/unikraft/unikraft/pull/425), requires reviews and updates

---

## Hardware Randomization

**Author**: Răzvan Deaconescu
**Owner**: Răzvan Deaconescu
**Tech lead**: Marc Rittinghaus
**Estimated duration**: 3 months
**Priority**: medium

**Rationale for topic relevance**

Hardware randomization is required for TRNG (True Random Number Generators).

**Summary of objectives**

- [ ] Provide arch-level random API (`ukarch_random`)
- [ ] Add hardware RNG for ARM
- [ ] Add hardware RNG for x86

**Prerequisites / dependencies**

- [ukcpuid](#ukcpuid)

**Notes**

- [`ukarch_random` PR is available](https://github.com/unikraft/unikraft/pull/434), waiting for review
- [PR on x86 hardware randomization](https://github.com/unikraft/unikraft/pull/420), requires updates

---

## procfs Support

**Author**: Răzvan Deaconescu
**Owner**: Răzvan Deaconescu
**Tech lead**: Simon Kuenzer
**Estimated duration**: 2 months
**Priority**: medium

**Rationale for topic relevance**

Applications built for Linux make use of proc filesystem entries.
With procfs support, more applications can be ported.

**Notes**

- procfs support will use ukstore entries, where possible / available.

---

## Musl Support

**Author**: Răzvan Deaconescu
**Owner**: Răzvan Deaconescu
**Tech lead**: Simon Kuenzer
**Estimated duration**: 1 month
**Priority**: high

**Rationale for topic relevance**

Add support for [Musl](https://www.musl-libc.org/) as standard C library in Unikraft.

**Summary of objectives**

- [ ] Port Musl
- [ ] Port / test threading support (including `clone` system call)
- [ ] Test and validate implementation

---

## libc Test Library

**Author**: Răzvan Deconescu
**Owner**: Răzvan Deaconescu
**Tech lead**: Simon Kuenzer
**Estimated duration**: 3 months
**Priority**: medium

**Rationale for topic relevance**

Port [libc-test](https://wiki.musl-libc.org/libc-test.html) to test libc interfaces such as Musl and newlib.

**Prerequisites / dependencies**

- [Musl Support](musl-support)

**Notes**

- Florin Postolache is involved

---

## ukstore (dynamic)

**Author**: Răzvan Deaconescu
**Owner**: Cezar Crăciunoiu
**Tech lead**: Simon Kuenzer
**Estimated duration**: 2 weeks
**Priority**: high

**Rationale for topic relevance**

Add dynamic entries in ukstore, the internal library for storing Unikraft data and passing it with getters / setters.

**Notes**

- [PR available](https://github.com/unikraft/unikraft/pull/460), waiting for review

---

## Memory Ballooning

**Author**: Răzvan Deaconescu
**Owner**: Cezar Crăciunoiu
**Tech lead**: Simon Kuenzer
**Estimated duration**: 1 month
**Priority**: low

**Rationale for topic relevance**

Implement memory ballooning driver for Unikraft.

**Summary of objectives**

- [ ] Implement memory ballooning support in KVM
- [ ] Implement memory ballooning support in Xen

**Notes**

- [PR available](https://github.com/unikraft/unikraft/pull/219), waiting for review

---

## Rust Support

**Author**: Răzvan Deaconescu
**Owner**: Răzvan Deaconescu
**Tech lead**: Vlad Bădoiu
**Estimated duration**: 2 months
**Priority**: high

**Rationale for topic relevance**

Add Rust support for external libraries / applications.
Applications written in Rust to be built on top of Unikraft.

**Notes**

- Dennis Kobert, Martin Koering are involved

---

## containerd integration

**Author**: Alexander Jung
**Owner**: Alexander Jung
**Tech lead**: Alexander Jung
**Estimated duration**: 1 month
**Priority**: high

**Rationale for topic relevance**

Increasing Unikraft applicability, ease-of-use, and relevance.

**Summary of objectives**

- [ ] `runu` etc.
- [ ] Cloud Native integrations: e.g. plugin to [k3s](https://k3s.io/)

**Notes**

- Iteration of shared libraries, and ability to pull them from environment

---

## Memory Randomization

**Author**: Răzvan Deaconescu
**Owner**: Hugo Lefeuvre
**Tech lead**: Marc Rittinghaus
**Estimated duration**: 4 months
**Priority**: medium

**Rationale for topic relevance**

Memory randomization is an important security feature in modern applications / operating sytems.
It would be added to the [Unikraft security features page](https://unikraft.org/docs/features/security/).

**Summary of objectives**

- [ ] The Unikraft image (or the prebuilt Linux ELF application binary) would be loaded at different virtual memory addresses.
- [ ] Given sections in the Unikraft image could be loaded at different virtual memory addresses, independent among themselves.
- [ ] Randomize the page table location.

**Prerequisites / dependencies**

- [Unikraft Loader](#unikraft-loader)
- [ELF Loader](#elf-loader)

**Notes**

- The randomization of dynamic sections (heap, stack) is not part of the loader.

---

## Unit Tests for Internal Libraries

**Author**: Răzvan Deaconescu
**Owner**: Răzvan Deaconescu
**Tech lead**: Library author
**Estimated duration**: 6 months
**Priority**: medium

**Rationale for topic relevance**

Unit testing ensure a good quality of the implementation.
Existence of unit tests allows regression testing: any new feature will be validated with existing unit tests.
Add unit tests (using [uktest](https://unikraft.org/docs/develop/writing-tests/)) for [internal Unikraft libraries](https://github.com/unikraft/unikraft/tree/staging/lib).

---

## Code Conventions

**Author**: Răzvan Deaconescu
**Owner**: Răzvan Deaconescu
**Tech lead**: Marc Rittinghaus
**Estimated Duration**: 2 months
**Priority**: high

**Rationale for topic relevance**

Using code conventions ensures consistency and good practices in written code.
Otherwise, we get different styles and a general confusion from the contributor: "How should I write this code?"

**Summary of objectives**

- [ ] Agree on code conventions for the Unikraft project.
- [ ] Publish code conventions on [Unikraft documentation website](https://unikraft.org/docs/).
- [ ] Update implementation to follow code conventions.

**Notes**

- Initial ideas [here](https://docs.google.com/document/d/1_iRkdBjQtnqOj798ZNr23OQTWQcXPdpDsnfBikm6Pcg/edit).

---

## ELF Loader

**Author**: Răzvan Deaconescu
**Owner**: Răzvan Deaconescu
**Tech lead**: Simon Kuenzer
**Estimated Duration**: 2 months
**Priority**: high

**Rationale for topic relevance**

Increase application adoption by directly running unmodified Linux ELF binaries on top of Unikraft.
The ELF Loader will load a given ELF binary and pass control to it.
System calls will be passed to the shim layer.

**Summary of objectives**

- [ ] Use random memory loading.
- [ ] Support for dynamically-linked executables.

**Notes**

- [Draft work from Simon Kuenzer](https://github.com/skuenzer/app-elfloader/tree/skuenzer/devel), needs cleanup and update to latest Unikraft version

---

## Unikraft Loader

**Author**: Răzvan Deaconescu
**Owner**: Răzvan Deaconescu
**Tech lead**: Simon Kuenzer
**Estimated Duration**: 6 months
**Priority**: medium

**Rationale for topic relevance**

Have a loader as part of the unikernel image (or use a separate image).
The loader will then load the actual unikernel in memory.
This enables random placing of the unikernel and possible other features (load the unikernel for a specific architecture).

**Summary of objectives**

- [ ] Design loader separation from core unikernel image.
- [ ] Implement for different bootloaders and platforms.
- [ ] Add dynamic linking of Unikraft micro libraries.
- [ ] Use random memory loading.

---

## Hyper-V Support

**Author**: Răzvan Deaconescu
**Owner**: Răzvan Deaconescu
**Tech lead**: Marc Rittingaus
**Estimated Duration**: 5 months
**Priority**: medium

**Rationale for topic relevance**

Add support for Hyper-V hypervisor.

**Summary of objectives**

- [ ] Add basic Hyper-V support.
- [ ] Add EFI support.
- [ ] Complete Hyper-V support.

**Prerequisites / dependencies**

- [Platform Rearchitecting](#platform-rearchitecting)

**Notes**

- Implementation done by Paul Vlase

---

## VMware Support

**Author**: Răzvan Deaconescu
**Owner**: Răzvan Deaconescu
**Tech lead**: Marc Rittingaus
**Estimated Duration**: 4 months
**Priority**: medium

**Rationale for topic relevance**

Add support for VMware hypervisor.

**Prerequisites / dependencies**

- [Platform Rearchitecting](#platform-rearchitecting)

**Notes**

- Implementation done by Paul Ungureanu

---

## Firecracker Support

**Author**: Răzvan Deaconescu
**Owner**: Răzvan Deaconescu
**Tech lead**: Simon Kuenzer
**Estimated Duration**: 3 months
**Priority**: high

**Rationale for topic relevance**

Add support for Firecracker VMM.

**Prerequisites / dependencies**

- [Platform Rearchitecting](#platform-rearchitecting)

**Notes**

- [Work in progress](https://github.com/Krechals/unikraft/tree/firecracker-mmio-0.8) by Andrei Topală

---

## Baremetal Support

**Author**: Răzvan Deaconescu
**Owner**: Răzvan Deaconescu
**Tech lead**: Michalis Pappas
**Estimated Duration**: 5 months
**Priority**: low

**Rationale for topic relevance**

Build Unikraft as a baremetal image, i.e. running directly on hardware, without support from a hypervisor.

**Prerequisites / dependencies**

- [Platform Rearchitecting](#platform-rearchitecting)

**Notes**

- Possible people to involve: Maria Sfîrăială

---

## Multiple Bootloaders

**Author**: Răzvan Deaconescu
**Owner**: Răzvan Deaconescu
**Tech lead**: Simon Kuenzer
**Estimated Duration**: 3 months
**Priority**: medium

**Rationale for topic relevance**

What happens if we boot from Multiboot, Multibootv2, uBoot.
If we build an image for QEMU/KVM we know it's Multiboot, and no need for other bootloader support.

This is tied to the plat rearch topic, due to the platform affecting the bootloader to be used.

**Summary of objectives**

- [ ] Add support for Multiboot2
- [ ] Add suport for uBoot

**Prerequisites / dependencies**

- [Platform Rearchitecting](#platform-rearchitecting)

**Others**

- Jamboard discussion [here](https://jamboard.google.com/d/1u5lHvXoIREkNJfqoNkqu6imxP7grAYbyDttx97W-Svo/viewer?f=0)

---

## Platform Rearchitecting

**Author**: Simon Kuenzer
**Owner**: Michalis Pappas
**Tech lead**: Simon Kuenzer
**Estimated Duration**: 6 months
**Priority**: high

**Rationale for topic relevance**

Reorganization of architecture and platform code, better re-using of implementations across targets and clear definition where which implementation should be placed.

---

## SMP-safe Unikraft Core

**Author**: Michalis Pappas
**Owner**: Michalis Pappas
**Tech lead**: Marc Rittingaus
**Estimated Duration**: 6 months
**Priority**: medium

**Rationale for topic relevance**

Make Unikraft core SMP-safe, i.e. Documentation of SMP-safe interfaces

**Others**

- Some work already being done by Sairaj (for GSoC)

---

## SMP-safe Memory Allocation

**Author**: Michalis Pappas
**Owner**: Michalis Pappas
**Tech lead**: Hugo Lefeuvre
**Estimated Duration**: 4 months
**Priority**: medium-high

**Rationale for topic relevance**

Implement support for memory allocation that works correctly in an SMP-environment.

**Notes**

- Likely going to be lock-free.
- Maybe use a separate SMP-safe allocator; so we would have both non-SMP-safe and SMP-safe allocators.
- Of interest to OpenSynergy

---

## POSIX mmap

**Author**: Michalis Pappas
**Owner**: Marc Rittinghaus
**Tech lead**: Marc Rittinghaus
**Estimated duration**: 4-8 weeks
**Priority**: high

**Rationale for topic relevance**

The current implementation of the mmap-group of functions is based on `malloc`. Unmapping does not work reliably with this. No support for paging code.

**Summary of objectives**

- [ ] Create data structure for efficient VA management (interval tree).
- [ ] Create uk-style API/library for VA management.
- [ ] Implement `posix-mmap` based on this API/library.
- [ ] Keep the options to switch back to "poor man's version" of `mmap` (such as when paging is not enabled).

**Others**

- Marc started implementing an initial version of `posix-mmap`

---

## W^X Support

**Author**: Marc Rittinhaus
**Owner**: Marc Rittinghaus
**Tech lead**: Michalis Pappas
**Estimated duration**: 1 week
**Priority**: medium

**Rationale for topic relevance**

Very important security feature.
Currently only supported on ARM (with paging) by setting up protections based on section information during boot.
General problem, section information incomplete.
Thus some protections are configured wrong -> crashes.

**Summary of objectives**

- [ ] Add W^X / DEP support using the NX / XD page bits on x86 / ARM.
- [ ] Generate static page table with correct protections as part of the build process (-> linker knows what sections exist and what protections are needed).

---

## uknofault

**Author**: Răzvan Deaconescu
**Owner**: Marc Rittinghaus
**Tech lead**: Marc Rittinghaus
**Estimated duration**: 2-4 weeks
**Priority**: medium

**Rationale for topic relevance**

Internal library that returns a code instead of a page fault.
Useful for debugging.

---

## GDB Stub

**Author**: Marc Rittinghaus
**Owner**: Marc Rittinghaus
**Tech lead**: Marc Rittinghaus
**Estimated duration**: 2 weeks (cleanup + upstream existing), +2 weeks (hw breakpoints, thread context support)
**Priority**: medium

**Rationale for topic relevance**

Enable GDB introspection of running Unikraft instance.
Provides the interface to list threads, memory allocations, open files in Unikraft etc.

**Summary of objectives**

- [ ] Add a GDB stub server in Unikraft, that a GDB client can connect to to debug the running unikernel instance.
- [ ] Add support for hardware breakpoints.

**Prerequisites / dependencies**

- Requires a second serial connection to Unikraft
- Cleanup work for ARM/x86
- `uknofault`

**Notes**

- Current working version of ARM and x86
- Going to do a constant stream of changes over time.

---

## Automated API Documentation

**Author**: Simon Kuenzer
**Owner**: Alexander Jung
**Tech lead**: Ștefan Jumărea
**Estimated Duration**: 4 months
**Priority**: medium-high

**Rationale for topic relevance**

Automatically generate API interface documentation from headers (e.g., doxystyle format).
To be published on https://unikraft.org/docs.

**Summary of objectives**

- [ ] Automate generation of API interface documentation.
- [ ] Complete and fix current interface documentation to the target annotation format.
- [ ] Include interface properties (for example indicating SMP-safety, thread-safety, reentrant-safety, isr-safety).

**Prerequisites / dependencies**

- [Code Conventions](#code-conventions)

---

## Core Library READMEs

**Author**: Alexander Jung
**Owner**: Alexander Jung
**Tech lead**: Ștefan Jumărea
**Estimated Duration**: 6 months
**Priority**: medium-high

**Rationale for topic relevance**

Introduce the relevant `README.md` file to each corresponding library.

---

## Kernel Log Exporting

**Author**: Simon Kuenzer
**Owner**: Răzvan Deaconescu
**Tech lead**: Marc Rittinghaus
**Estimated Duration**: 4 months
**Priority**: medium

**Rationale for topic relevance**

Integration in monitoring/debugging systems of kernel logging via a remote console

**Summary of objectives**

- [ ] Output kernel messages to different outputs:
- log buffer (like dmesg)
- Syslog client
- Shell/SSH

**Others**

- Draft work from Alexandra Pîrvulescu

---

## Unikraft Packaging

**Author**: Răzvan Deaconescu
**Owner**: Răzvan Deaconescu
**Tech lead**: Alexander Jung
**Estimated Duration**: 4 months
**Priority**: medium

**Rationale for topic relevance**

Deliver Unikraft and support filesystem / disk as unified image.
The image will be passed to the VMM.

**Summary of objectives**

- [ ] Add support in build system.
- [ ] Build sample images for supported applications.
- [ ] KraftKit target flavour.

**Prerequisites / dependencies**

- [Multiple Bootloaders](#multiple-bootloaders)

**Notes**

- Jamboard discussion [here](https://jamboard.google.com/d/1u5lHvXoIREkNJfqoNkqu6imxP7grAYbyDttx97W-Svo/edit?usp=sharing)

---

## RISC-V Support

**Author**: Răzvan Deaconescu
**Owner**: Răzvan Deaconescu
**Tech lead**: Michalis Pappas
**Estimated Duration**: 1 month
**Priority**: medium

**Rationale for topic relevance**

Add support for RISC-V architecture.

**Summary of objectives**

- [ ] Add SMP support.
- [ ] Do code restructuring during/after platform rearchitecting.
- [ ] Add any other features that may be currently missing from the RISC-V port and are present in other architectures.

**Prerequisites / dependencies**

- [Platform Rearchitecting](#platform-rearchitecting)

**Notes**

- [Draft PR from Eduard Vintilă](https://github.com/unikraft/unikraft/pull/461), requires review
- Core implementation already done and working with the latest (0.10) release. Needs reviewing, more thorough testing and (very probably) some refactoring.

---

## Driver Shim Layer

**Author**: Răzvan Deaconescu
**Owner**: Răzvan Deaconescu
**Tech lead**: Simon Kuenzer
**Estimated Duration**: 4 months
**Priority**: low

**Rationale for topic relevance**

Implement software layer to port drivers.

**Summary of objectives**

- [ ] Provide driver shim layer as specialized library.
- [ ] Port sample drivers from FreeRTOS

**Prerequisites / dependencies**

- [Baremetal Support](#baremetal-support)

**Notes**

- [Draft work](https://github.com/unikraft/driver-shim) from Andreea Dumitrache

---

## Signal Reimplementation

**Author**: Simon Kuenzer
**Owner**: Simon Kuenzer
**Tech lead**: Simon Kuenzer
**Estimated Duration**: 4 months
**Priority**: high

**Rationale for topic relevance**

Support handling and delivery of signals.

**Summary of objectives**

- [ ] Rewrite singals implementation within posix-process (currently broken)
- [ ] Signal delivery withinstruction pointer injection to a thread's context?
- [ ] Support signal handler stack switches, maybe some scheduling API extensions are needed
- [ ] Map platform requests to signals to the application (e.g., shutdown request as `SIGQUIT`)

---

## ISR-Safe Code

**Author**: Simon Kuenzer
**Owner**: Răzvan Deaconescu
**Tech lead**: Simon Kuenzer
**Estimated Duration**: 3 months
**Priority**: high

**Rationale for topic relevance**

We compile Unikraft with all compiler and CPU optimizations enabled. However, due to missing context saving of extended CPU units (vector, floating point) on interrupt/trap handlers, we need to make somehow sure that those functions are not using such registers because otherwise the original program flow might corrupt.
`isrlib` was introduced with a subset of `nolibc` functions that are compiled to be safe to be used in an interrupt service routine (ISR-safe).

**Summary of objectives**

- [ ] Enforce ISR-guarantee: An ISR-safe function should never call a non-ISR-safe function: Linker/compile tricks (e.g., compile isr functions into own section and forbid linking them with other non-isr sections (opposite direction is okay, actually)) or static analysis?
- [ ] Revisit compiler attributes: https://gcc.gnu.org/onlinedocs/gcc-12.2.0/gcc/Common-Function-Attributes.html#Common-Function-Attributes (`target` is worth a look). Maybe the `isr` variant in `Makefile.uk` is not needed anymore
- [ ] Make sure all interrupt handler paths are covered with ISR-safe property (drivers, trap handlers, ...)

**Notes**

- Possible people: Adina, CristiV

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## Unikraft System Shutdown

**Author**: Simon Kuenzer
**Owner**: Simon Kuenzer
**Tech lead**: Simon Kuenzer
**Estimated Duration**: 1-2 week
**Priority**: high

**Rationale for topic relevance**

Enables clean unmounting of filesystems and flushing of disk block caches.

**Summary of objectives**

- [ ] Extend `uk_inittab` with corresponding termination function field.
- [ ] Add shutdown handling to `lib/ukboot` (call in reverse priority order).

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