what issue tracking software does linux development use?

The reason I ask this is because it seems silly to me to contrive an issue tracking system for git when linux development must already have one that works perfectly for git. In fact, git is designed around linux development (from everything I understand), and so as far as I can tell, git must implicitly already have/work-with an issue-tra开发者_C百科cking system.

Perhaps linux development doesn't use issue tracking software, but surely the developers have some system.

What issue tracking system does linux development use?

Bugzilla?

Also, see this.