TY - GEN A1 - Alglave, J A1 - Maranget, L A1 - McKenney, PE A1 - Parri, A A1 - Stern, A CY - Williamsburg, VA, USA SP - 405 EP - 418 SN - 1558-1160 ID - discovery10070727 AV - public TI - Frightening Small Children and Disconcerting Grown-ups: Concurrency in the Linux Kernel N1 - This version is the author accepted manuscript. For information on re-use, please refer to the publisher?s terms and conditions. UR - https://doi.org/10.1145/3173162.3177156 Y1 - 2018/03/28/ N2 - Concurrency in the Linux kernel can be a contentious topic. The Linux kernel mailing list features numerous discussions related to consistency models, including those of the more than 30 CPU architectures supported by the kernel and that of the kernel itself. How are Linux programs supposed to behave? Do they behave correctly on exotic hardware? A formal model can help address such questions. Better yet, an executable model allows programmers to experiment with the model to develop their intuition. Thus we offer a model written in the cat language, making it not only formal, but also executable by the herd simulator. We tested our model against hardware and refined it in consultation with maintainers. Finally, we formalised the fundamental law of the Read-Copy-Update synchronisation mechanism, and proved that one of its implementations satisfies this law. PB - ACM ER -