How we spent two weeks hunting an NFS bug in the Linux kernel

What this post added

This post details the debugging process for a 'Stale file handle' error encountered with NFS, specifically on Linux v4.0 clients. It describes reproducing the bug using a controlled experiment involving file renames and open file handles, and analyzing NFS traffic with tcpdump and Wireshark to compare NFS v4.0 and v4.1 behavior. The investigation revealed a potential issue with NFS server delegations and the handling of file handle staleness during renames, leading to a kernel patch.