Re: [PATCH] checkpatch: Validate committer sign-off

[Bjorn Andersson]

On Sat, Jul 25, 2026 at 03:47:34PM -0700, Joe Perches wrote:
> On Fri, 2026-07-24 at 18:56 +0000, Bjorn Andersson wrote:
> > ```
> > checkpatch validates the Signed-off-by trailers against the patch's
> > author, but misses the opportunity to also validate the committer when
> > run with --git. Maintainers therefor need third-party scripts for the
> > final Signed-off-by check.
> 
> I don't actually see that need as an issue for checkpatch.
> 
> checkpatch is for patches, not things that are already committed.
> 

Fair, this is only applicable for people managing/receiving/collecting
patches - be it maintainers or people gathering patches and then resend
them...

I didn't dig deeper, but my LLM found 32 cases in the last 90 days where
linux-next maintainers points out missing committer sobs, so it seems
like making this check more conveniently accessible would help more than
me.

> If something like this is added, it should _only_ be used when
> --git is on the command line.

The 3rd hunk (that extracts commiter, sha1 and subject) only runs "if
$(git)", and hence $committer (from $git_committers{$filename}) will be
'', as such signoff_match_status($1, $committer) will not be evaluated,
and the check will be skipped.

Regards,
Bjorn