The art of writing eBPF programs: a primer.

The blog post titled "The art of writing eBPF programs: a primer" by Gianluca Borello delves into the process of writing eBPF programs with a focus on system call tracing, specifically using the openat system call as an example. The post outlines the verification process and the role of the eBPF virtual machine in ensuring runtime safety, emphasizing that writing complex eBPF programs requires significant context. The author explains how eBPF programs can be written using examples, detailing the use of eBPF helpers like bpf_probe_read and bpf_probe_read_str to safely access memory and strings. The post also discusses the importance of eBPF maps for storing data safely across program invocations and highlights challenges such as managing variable memory accesses and ensuring verifier compliance. By providing code examples and insights into bytecode analysis, the blog aims to enhance understanding of the eBPF programming process, while acknowledging the evolving nature of eBPF technology and the challenges of maintaining backward compatibility across different kernel versions.