[PATCH v2 3/5] SubmittingPatches: document Based-on-patch-by trailer

[kristofferhaugsbakk@fastmail.com]

From: Kristoffer Haugsbakk <code@khaugsbakk.name>

This trailer comes up often enough and the use case is not fully covered
by the other trailers here. For example, it is sometimes better to use
this trailer instead of `Co-authored-by:`.

Signed-off-by: Kristoffer Haugsbakk <code@khaugsbakk.name>
---

Notes (series):
    v2:
    • Do *not* say *without sign-off*; do mention the precondition that
      it is signed off, and cover the case when the patch author did not
      sign off on it
      • https://lore.kernel.org/git/xmqqse6tnho1.fsf@gitster.g/
    • Drop “without a commit message”. It doesn’t seem important. A bare
      patch is just a patch, not a patch plus a message.

 Documentation/SubmittingPatches | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Documentation/SubmittingPatches b/Documentation/SubmittingPatches
index 38e18982aa2..4a37bc29f5a 100644
--- a/Documentation/SubmittingPatches
+++ b/Documentation/SubmittingPatches
@@ -465,6 +465,10 @@ These are the common trailers in use:
   and found it to have the desired effect.
 . `Co-authored-by:` is used to indicate that people exchanged drafts
    of a patch before submitting it.
+. `Based-on-patch-by:` is used when someone else authored parts of the
+  patch that you are submitting. This might be relevant if someone sent
+  a patch to the mailing list with their sign-off. (Be mindful and ask
+  them to sign off on it if they did not.)
 . `Helped-by:` is used to credit someone who suggested ideas for
   changes without providing the precise changes in patch form.
 . `Mentored-by:` is used to credit someone with helping develop a
-- 
2.54.0.22.g9e26862b904