Arnd Bergmann
What role do you play in the community and/or what subsystem(s) do you work on?
I am co-maintaining the arm-soc kernel tree together with Olof Johansson. We pick up patches from dozens of ARM subarchitecture maintainers and consolidate patches for the merge window to send them upstream to Linus Torvalds. This nowadays amounts to about 1000 patches for each merge window.