Before moving to Bitkeeper, Linus was not using any source control for the kernel (he ‘'’may’’’ have been using CVS for his own use (not sure) but nothing publicly accessible). And essentially ‘'’all’’’ patches had to go through him.

From 2001:

http://www.kerneltraffic.org/kernel-traffic/kt20010903_131.html#10

Alan Cox said about the possibility of Linux getting source control, “It does. Or at least many of the development teams do. That doesn’t mean a general CVS is a good idea. CVS make it all to easy for other people to push crap into your tree.” Gerard Roudier asked, “What other people? You can only allow trusted people to commit, and backing out crap is quite easy.” Alan replied, “This is the model we use. The trust people list is Linus Torvalds.” Gerard replied, “You just pointed out the problem. Linus being the only trusted committer for more than 100 MB of source base as he was for less than 1 MB 10 years ago.

http://www.kerneltraffic.org/kernel-traffic/kt20020218_154.html#3

Feb 2002:

Linus: “The long-range plan, and the real payoff, comes if main developers start using bk too, which should make syncing a lot easier.”

http://www.kerneltraffic.org/kernel-traffic/kt20020415_162.html#5

Larry McVoy: “Linus created his tree on 2002-04-03 17:03:45-08:00.”

MangResearchKernelShaikhCornford