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From:   Andy Lutomirski <luto@kernel.org>
Date:   Fri, 1 Feb 2019 18:42:29 -0800
Message-ID: <CALCETrXi=PEOXCQYkCO9BLL+oaoJonRohWoxvUqxZdiWURc3=Q@mail.gmail.com>
Subject: Re: [PATCH v5 01/13] taint: Introduce a new taint flag (insecure)
To:     "Chang S. Bae" <chang.seok.bae@intel.com>,
        Andrew Morton <akpm@linux-foundation.org>
Cc:     Andy Lutomirski <luto@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@kernel.org>,
        "H . Peter Anvin" <hpa@zytor.com>, Andi Kleen <ak@linux.intel.com>,
        Markus T Metzger <markus.t.metzger@intel.com>,
        Ravi Shankar <ravi.v.shankar@intel.com>,
        LKML <linux-kernel@vger.kernel.org>
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On Fri, Feb 1, 2019 at 12:54 PM Chang S. Bae <chang.seok.bae@intel.com> wrote:
>
> For testing (or root-only) purposes, the new flag will serve to tag the
> kernel taint accurately.
>
> When adding a new feature support, patches need to be incrementally
> applied and tested with temporal parameters. Currently, there is no flag
> for this usage.

I think this should be reviewed by someone like akpm.  akpm, for
background, this is part of an x86 patch series.  If only part of the
series is applied, the kernel will be blatantly insecure (but still
functional and useful for testing and bisection), and this taint flag
will be set if this kernel is booted.  With the whole series applied,
there are no users of the taint flag in the kernel.

Do you think this is a good idea?