A debugging story: corrupt packets in AF_XDP; a kernel bug or user error?
Jan 16, 2023Shawn Bohrer, Bastien Dhiver

Summary
This post details a deep dive into debugging a critical issue with AF_XDP, a high-performance networking API. It highlights the process of identifying and resolving a bug that caused packet corruption due to descriptors being used twice across different rings. The contribution lies in demonstrating Cloudflare's commitment to optimizing and ensuring the reliability of its low-level network infrastructure, including the meticulous debugging of kernel interactions and user-space applications to maintain network performance and security.
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