Re: [PATCH v2 2/3] maint: Tweak comments in mailmap regarding SPF

[Eric Blake]

On Wed, Sep 27, 2023 at 09:38:18AM -0500, Eric Blake wrote:
> From: Eric Blake <eblake@redhat.com>
> 
> Documenting that we should not add new lines to work around SPF
> rewrites sounds foreboding; the intent is instead that new lines here
> are okay, but indicate a second problem elsewhere in our build process
> that we should also consider fixing at the same time, to keep the
> section from growing without bounds.  While we have been doing that
> for qemu-devel for a while, we jut recently fixed that for qemu-block:
> https://git.linaro.org/people/pmaydell/misc-scripts.git/commit/?id=f9a317392
> 
> Mentioning DMARC alongside SPF may also help people grep for this
> scenario, as well as documenting the 'git config' workaround that can
> be used by submitters to avoid the munging issue in the first place.
> 
> Note the subtelty: 'git commit' sets authorship information based on

subtlety

> user.name and user.email (where name is usually unquoted); while 'git
> format-patch' includes a body 'From:' line only when sendemail.from is

s/format-patch/send-email/

The comments in the patch proper were correct, but the commit message
needs a tweak.  Based on my testing, 'git send-email --annotate'
invokes the editor on the output of an implicit 'git format-patch',
which does not have a body from line yet; it is the post-processing
step of send-email that finally adds it.

> present but differs from authorship information.  Hence the use of
> quotes in sendemail.from (not a semantic change to email, but enough
> of a difference to add the body 'From:').
> 
> Fixes: 3bd2608d ("maint: Add .mailmap entries for patches claiming list 
> authorship")
> CC: Andrey Drobyshev <andrey.drobyshev@virtuozzo.com>
> Cc: Peter Maydell <peter.maydell@linaro.org>
> Signed-off-by: Eric Blake <eblake@redhat.com>
> ---
> 
> Once again, sending this patch to the list with my git config
> temporarily changed.  I used a command line:
>  git config sendemail.from '"Eric Blake" <eblakeWredhat.com>'
> which turned into this in my .git/config:
> [sendemail]
>   from = \"Eric Blake\" <eblake@redhat.com>
> 
> My editor window in 'git send-email' doesn't show the body from line,
> but hopefully the list archives do (that is, the addition of a body
> From appears to be a post-processing step done by git after my editor
> window closes but before the final mail is actually shoved out my MUA)

Yay, it appears to have worked!

https://patchew.org/search?q=project%3AQEMU+from%3ABlake

lists this series under 'Eric Blake' rather than 'eblake@redhat.com';
and inspecting the mail headers shows that the "" were indeed present
in the headers, while git inserted a body From because it was not
identical to the actual commit authorship without quotes.

> ---
>  .mailmap | 14 +++++++++++++-
>  1 file changed, 13 insertions(+), 1 deletion(-)
> 
> diff --git a/.mailmap b/.mailmap
> index 04a7feb005b..fadf6e74506 100644
> --- a/.mailmap
> +++ b/.mailmap
> @@ -40,7 +40,19 @@ Nick Hudson <hnick@vmware.com> hnick@vmware.com 
> <hnick@vmware.com>
>  # for the cvs2svn initialization commit e63c3dc74bf.
> 
>  # Next, translate a few commits where mailman rewrote the From: line due
> -# to strict SPF, although we prefer to avoid adding more entries like that.
> +# to strict SPF and DMARC.  Usually, our build process should be flagging
> +# commits like these before maintainer merges; if you find the need to add
> +# a line here, please also report a bug against the part of the build
> +# process that let the mis-attribution slip through in the first place.
> +#
> +# If the mailing list munges your emails, use:
> +#   git config sendemail.from '"Your Name" <your.email@example.com>'
> +# the use of "" in that line will differ from the typically unquoted
> +# 'git config user.name', which in turn is sufficient for 'git send-email'
> +# to add an extra From: line in the body of your email that takes
> +# precedence over any munged From: in the mail's headers.
> +# See https://lists.openembedded.org/g/openembedded-core/message/166515
> +# and https://lists.gnu.org/archive/html/qemu-devel/2023-09/msg06784.html
>  Ed Swierk <eswierk@skyportsystems.com> Ed Swierk via Qemu-devel 
> <qemu-devel@nongnu.org>
>  Ian McKellar <ianloic@google.com> Ian McKellar via Qemu-devel 
> <qemu-devel@nongnu.org>
>  Julia Suvorova <jusual@mail.ru> Julia Suvorova via Qemu-devel 
> <qemu-devel@nongnu.org>
> -- 
> 2.41.0
> 

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.
Virtualization:  qemu.org | libguestfs.org