Linux kernel developers are self-reported in the file /usr/src/linux/CREDITS. If their names weren't entered there, I didn't find them. Furthermore, there are many more who contribute by testing various development releases and reporting on the problems. Sometimes they even report possible source code corrections, but they aren't included in the CREDITS file.
Linux consists of much more than just the kernel. There are a host of related programs, such as those which are broadly distributed by the Free Software Foundation for UNIX and other operating system users, and others which support only Linux.
It would take significant effort to identify all those who have contributed to make Linux a success. The Debian project reports who is working on that distribution, but that's not enough. I'd like to see a CREDITS file in every package and tar file. I'd appreciate hearing of efforts along this line.