Re: mb2q experience and couple issues

[Daniel Borkmann]

On 10/1/20 11:13 AM, Thomas Gleixner wrote:
> On Wed, Sep 30 2020 at 11:12, Alexei Starovoitov wrote:
> > For the last couple years we've been using mb2q tool to normalize patches
> > and it worked wonderfully.
>
> Fun. I thought I'm the only user of it :)

We're using it pretty much daily since you've put it on korg :) It's in
a bunch of scripts^hacks we use for bpf trees:

  https://git.kernel.org/pub/scm/linux/kernel/git/dborkman/pw.git/

> > Recently we've hit few bugs:
> > curl -s https://patchwork.kernel.org/patch/11807443/mbox/ >
> > /tmp/mbox.i; ~/bin/mb2q --mboxout mbox.o /tmp/mbox.i
> > Drop Message w/o Message-ID: No subject
> > No patches found in mbox
> >
> > I've tried to debug it, but couldn't figure out what's going on.
> > The subject and message-id fields are parsed correctly,
> > but later something happens.
> > Could you please take a look?
>
> The problem is the mbox storage format. The mbox created by curl has a
> mail body which has a line starting with 'From' in the mail body:
>
>    From the VAR btf_id, the verifier can also read the address of the
>    ksym's corresponding kernel var from kallsyms and use that to fill
>    dst_reg.
>
> The mailbox parser trips over that From and takes it as start of the
> next message.
>
>       http://qmail.org/qmail-manual-html/man5/mbox.html
>
> Usually mailbox storage escapes a From at the start of a
> newline with '>':
>
>    >From the VAR btf_id, the verifier can also read the address of the
>    ksym's corresponding kernel var from kallsyms and use that to fill
>    dst_reg.
>
> Yes, it's ugly and I haven't figured out a proper way to deal with
> that. There are quite some mbox formats out there and they all are
> incompatible with each other and all of them have different horrors.
>
> Let me think about it.

It seems these issues only appeared since maybe a month or so. Perhaps also
something changed on ozlabs/patchwork side.

Cheers,
Daniel