OrangePi SDK linux kernel-3.4.112
http://soilhead.cn/static/orangepi/sdk.html
WHAT IS LINUX?
Linux is a clone of the operating system Unix, written from scratch by Linus Torvalds with assistance from a loosely-knit team of hackers across the Net. It aims towards POSIX and Single UNIX Specification compliance.
It has all the features you would expect in a modern fully-fledged Unix, including true multitasking, virtual memory, shared libraries, demand loading, shared copy-on-write executables, proper memory management, and multistack networking including IPv4 and IPv6.
It is distributed under the GNU General Public License - see the accompanying COPYING file for more details.