What makes a good Git commit?

Links:

• Commit Message Guidelines
• OpenStack advice
• Chris Beams' advice
• Stack Overflow advice
• SlideShare presentation

Any other good ones?

• Subject (first) line (followed by blank line):
  • 60 char max (including subsystem name) for git log --oneline).

8c7ae38d1ce1 afs: Fix StoreData op marshalling
7d6ab823d646 vfs: Update mount API docs
b6ffdf27f3d4 s390/cpumf: Fix warning from check_processor_id
01f2f5b82a2b SUNRPC: fix uninitialized variable warning
8c838f53e149 dpaa2-eth: fix race condition with bql frame accounting
047a013f8d0a chelsio: use BUG() instead of BUG_ON(1)

• Be accurate; the subject must describe the actual commit.
• Use the imperative mood (“Fix”, “Adjust”, “Correct”).
• Don't capitalize the first word.
• No ending period.
• Is this changing functionality, or just fixing docs/comments.
• Commits themselves:
• Well-defined and modular, for future cherry picking or reverting.
• Complete; use git commit --amend to assure this.
• Commit messages:
• What is being changed, what functionality is being affected (if any).
• Why it is being changed.
• References to discussions about this commit (people, mailing lists).
• Level of testing this commit has had.
• Names of others who have ACKed/tested/reviewed this commit.
• References to bug tracker items (JIRA) this commit is addressing.

$ git show --summary 6ff005cf19363382fc867d7876a75fd8a386e894
commit 6ff005cf19363382fc867d7876a75fd8a386e894
Author: Dave Prue <dave@prue.com>
Date:   Thu Aug 31 19:21:01 2017 +0200

    sunxi: Fix CONFIG_SUNXI_GMAC references
    
    SUNXI_GMAC was still used to configure the code where as the
    same has been renamed and moved to Kconfig in below commit
    "sunxi: Move SUNXI_GMAC to Kconfig"
    (sha1: 4d43d065db3262f9a9918ba72457bf36dfb8e0bb)
    
    Signed-off-by: Dave Prue <dave@prue.com>
    Reviewed-by: Simon Glass <sjg@chromium.org>
    Reviewed-by: Jagan Teki <jagan@openedev.com>
    Reviewed-by: Mark Kettenis <kettenis@openbsd.org>
    Tested-by: Mark Kettenis <kettenis@openbsd.org>
    [Tweek commit message, config_whitelist.txt, build-whitelist.sh]
    Signed-off-by: Jagan Teki <jagan@openedev.com>