How to send a v2 patch

When a maintainer asks you to make changes to a patch, you have to start over from scratch and resend it as a version 2 patch. There are two main things that a v2 patch needs to have.

1) Put v2 in the subject.

[PATCH v2] subsystem: Do whatever thing

You can use the -v2 option on “git send-email -v2 -1” to do this.

2) After the — cut off list the changes you have made.

Signed-off-by: Your Name <email>
---
v3: Fix typo in commit message
v2: Fix error code

The notes after the — cut off will not be recorded in the permanent git log.

Do not resend a patch on the same day. There is no rush. Maybe more than one person will want to review your patch so give them a day to respond. Plus resending that same day means you haven’t tested the patch.

If only one patch in a patchset needs to be redone, then resend the whole patchset. It used to be that maintainers would apply patches manually one by one so you could send a v2 for just one patch and the maintainer would pick it up but these days maintainers prefer to apply a whole patchset at a time.

Do not use the –in-reply-to option. In olden times people would send their v2 patch as a reply to the first patch. But it can make for a confusing email thread. Humans get confused and also Patchwork gets confused so it doesn’t work at all. Just start a new thread for every resend.

However, one thing that I sometimes see is when people spot a problem in their own code and resend. In that situation you *must* send a note to the original thread to say “Please do not apply this.” If there is no reply to the patch, then how is the maintainer supposed to know?