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Date:   Mon, 20 Apr 2020 11:34:34 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Christoph Hellwig <hch@infradead.org>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        LKML <linux-kernel@vger.kernel.org>, x86@kernel.org,
        Kees Cook <keescook@chromium.org>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Thomas Lendacky <Thomas.Lendacky@amd.com>,
        Juergen Gross <jgross@suse.com>,
        Boris Ostrovsky <boris.ostrovsky@oracle.com>
Subject: Re: [patch 02/15] x86/cpu: Uninline CR4 accessors
Message-ID: <20200420093434.GB3147@zn.tnic>
References: <20200419203137.214111265@linutronix.de>
 <20200419203335.856333226@linutronix.de>
 <20200420090102.GB24518@infradead.org>
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On Mon, Apr 20, 2020 at 02:01:02AM -0700, Christoph Hellwig wrote:
> While this is better than what we had before we really need to have
> a discussion on lkdtm - it needs a lot of crap that otherwise wouldn't
> be exported, and I'm really worried about people enabling it and thus
> adding exports even if they are conditional.

Thought the same too, while looking at that. It is fine and dandy that
it injects all kinds of crap into a running kernel but not at the price
of exporting such internal interfaces.

> Can we force the code to be built in require a boot option for it to
> be activated?

Yes please.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette