[$] Rebasing and merging in kernel repositories

Maintaining a subsystem, as a general rule, requires a familiarity with theGit source-code management system. Git is a powerful tool with a lot offeatures; as is often the case with such tools, there are right and wrongways to use those features. This document looks in particular at the useof rebasing and merging. Maintainers often get in trouble when they usethose tools incorrectly, but avoiding problems is not actually all thathard.