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From:   "Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>
Date:   Sat, 29 Sep 2018 00:16:43 +0200
Message-ID: <CAKgNAkgcHENKrT=n4_YbmxJCOaY2Z+SXJcfuw9j7uOJwgym3Dg@mail.gmail.com>
Subject: Re: [PATCH v7 0/6] seccomp trap to userspace
To:     Tycho Andersen <tycho@tycho.ws>
Cc:     Kees Cook <keescook@chromium.org>,
        lkml <linux-kernel@vger.kernel.org>,
        Containers <containers@lists.linux-foundation.org>,
        Linux API <linux-api@vger.kernel.org>,
        Andy Lutomirski <luto@amacapital.net>,
        Oleg Nesterov <oleg@redhat.com>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
        "Serge E. Hallyn" <serge@hallyn.com>,
        Christian Brauner <christian.brauner@ubuntu.com>,
        Tyler Hicks <tyhicks@canonical.com>,
        Akihiro Suda <suda.akihiro@lab.ntt.co.jp>,
        Jann Horn <jannh@google.com>,
        "linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>
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Hi Tycho,

On Sat, 29 Sep 2018 at 00:04, Tycho Andersen <tycho@tycho.ws> wrote:
>
> On Fri, Sep 28, 2018 at 11:57:40PM +0200, Michael Kerrisk (man-opages) wrote:
> > Hi Tycho,
> >
> > On 09/27/2018 05:11 PM, Tycho Andersen wrote:
> > > Hi all,
> > >
> > > Here's v7 of the seccomp trap to userspace set. There are various minor
> > > changes and bug fixes, but two major changes:
> > >
> > > * We now pass fds to the tracee via an ioctl, and do it immediately when
> > >    the ioctl is called. For this we needed some help from the vfs, so
> > >    I've put the one patch in this series and cc'd fsdevel. This does have
> > >    the advantage that the feature is now totally decoupled from the rest
> > >    of the set, which is itself useful (thanks Andy!)
> > >
> > > * Instead of putting all of the notification related stuff into the
> > >    struct seccomp_filter, it now lives in its own struct notification,
> > >    which is pointed to by struct seccomp_filter. This will save a lot of
> > >    memory (thanks Tyler!)
> >
> > Is there a documentation (man page) patch for this API change?
>
> Not yet, but once we decide on a final API I'll prepare one.

Honestly, the production of such documentation should be part of the
evolution towards the final API...

Documentation is not an afterthought. It's a tool for pushing you, the
developer (and others, your reviewers) to more deeply consider your
design.

Thanks,

Michael
-- 
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
Linux/UNIX System Programming Training: http://man7.org/training/