When a Linux userspace application performs disk I/O – such as writing to an SD card, those requests go through a complex journey across multiple kernel components. These components aim to deliver optimal I/O performance whilst balancing a variety of needs such as latency and fairness. However, when things go wrong, it can be challenging …
Category: Tech Blog
Automated Testing with GitHub Actions, pytest and a Board Farm
When developing software it can be a real challenge to consistently deliver new features on time and without regressions. It can often feel like development gets stuck at the point of trying to get a new release out of the door with mountains of issues suddenly appearing. In an effort to improve development velocity many …
Linux Yocto layer for the ARM Morello board
We have recently developed and now maintain the meta-morello Yocto layer for ARM’s Morello board which has now became part of the official software stack. The layer is capable of providing the firmware image that goes on the SD card and a bootable image with Linux that goes on the USB stick, these two images …
Self-installing Yocto Image from a USB drive
We are all familiar with the process of installing a desktop operating system onto a PC; simply insert the installation media, typically a USB stick, and boot the device. A minimal version of the OS then runs to perform the process of partitioning discs and installing the full OS. Yocto also has the ability to …
SWUpdate, Suricatta and Unreliable Connectivity
Many product makers choose to use the open-source SWUpdate software to provide an off the shelf method of software update for their embedded devices. For internet connected devices this is typically configured in Suricatta daemon mode which allows for SWUpdate to poll for software updates from an update server such as the open-source Eclipse Hawkbit. …
Debugging a Memory Leak in a Large and Complex GStreamer Pipeline
GStreamer is a widely used and comprehensive multimedia framework allowing for the creation of a wide range of multimedia applications. It has become the obvious choice for embedded Linux systems, especially given that these days most BSP vendors choose to provide GStreamer plugins for their media accelerators. It’s ease of use allows you to create …
ARM Morello with Linux
ARM has recently made their Morello development on the Linux kernel public and since we are lucky enough to have access to the Morello board we decided to give this a spin. This is in contrast to our last blog post which used an Android stack and ran in a simulator. Kernel development in the …
Delta OTA Update with SWUpdate
With the complexity and dependence on software ever growing, it’s crucial to be able to perform over-the-air (OTA) updates to devices to provide fixes, features and patches for security vulnerabilities. However, a combination of cheap storage and complex software stacks has resulted in an increase in the size of software distributions thus requiring devices to …
Baking Android for ARM Morello without Morello
Access to ARM Morello boards is fairly limited at the moment, but we can still explore the new architecture with the help of a Fixed Virtual Platform (FVP) and software stack packages that are available from ARM. In a previous blog post we provided an introduction to Arm Morello and CHERI. In this post we’re …
Introducing Arm Morello and CHERI
Most serious errors and security threats in software originate from pointer overflows, pointer overwrite and memory miss-management. This causes invalid/un-authorised memory addresses to be interpreted as valid references which in turn results in applications accessing restricted or unavailable memory. Such access can be exploited by an attacker to inject malicious data into memory, take control …