After some investigation, the problem appeared to be in the Linux network file system (NFS) kernel, the piece of the operating system responsible for some basic server functions.

CNN: Linux gaining with mission-critical systems

Ubuntu is the most popular operating system to be based on the Linux kernel - the code that lets software and hardware work together.

BBC: Ubuntu operating system comes to Android smartphones

Coverity's founders, four graduate students from Stanford University and their professor, recently grammar-checked the entire Linux 2.6.9 kernel operating system and found a respectably low 950 bugs in 5.5 million lines.

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