2. LinuxKernelDevelopmentProcess

Release Cycle Step 2

2 Week Merge Window: Maintainers send git pull requests to Linus goes through the cycle of pulling each request and testing during the merge window.

Quiet Period

From about a week before the release through the 2 week merge window. So 3 weeks in total.

Kernel Tree

Kernel Git Repo, can be either Main or a Subsytem

Release Cycle Step 3

Linus releases Release Candidate 5.3-rc1: Merge Window is closed, and the 6-7 week integration cycle for fixing bugs, and regressions, begins

Release Cycle Step 1

Linus releases mainline 5.2

Long-Term Release

Long-Term Releases are stable releases selected for long-term maintenance to provide critical bug fixes for older kernel trees. Stable releases are normally only maintained for a few mainline release cycles

More Linux-Next Tree

Patches in Linux-Next after and during the merge window are for the Next Release.

Release Candidate

Release Candidate or RC releases are mainline kernel pre-releases that are used for testing features in the mainline. These releases must be compiled from source. Kernel developers test these releases for bugs and regressions

Patches

Small incremental changes that might add new features, make enhancements, or fix bugs

Release Cycle Step 4

Stable Release Cycle Process: First Stable 5.2.1 released with bug fixes from mainline (5.3.-rc1) with other active stable releases. Bug fixes will be included in all active stable releases.

Stable Release

Stable releases are bug fix-only releases. After Linus releases a mainline kernel, it moves into a stable mode. Any bug fixes for a stable kernel are back ported from the mainline kernel and applied to a stable git by a designated stable kernel release maintainer. Stable kernels are released on average, once a week, or on an as needed basis

Mainline Kernel Tree

The tree is maintained by Linus Torvalds. This is where Linus releases mainline kernels and rc releases

Stable Tree

The tree maintained by Greg Kroah-Hartman. This tree holds the stable release branches

Linux-Next Tree

This is the integration tree maintained by Stephen Rothwell. Code from a large number of subsytem trees gets pulled into this tree periodically and then released for integration testing. The process of pulling changes from various trees catches merge conflicts (if any) between trees

Release Cycle Step 5

Will there be a rc8?: Linus releases the mainline stable after rc7 or rc8 based on his confidence level of the quality