Date: Tue, 9 Jan 2018 22:29:40 +0100
From: Borislav Petkov <bp@alien8.de>
To: Andy Lutomirski <luto@kernel.org>
Cc: Willy Tarreau <w@1wt.eu>, LKML <linux-kernel@vger.kernel.org>,
        X86 ML <x86@kernel.org>, Brian Gerst <brgerst@gmail.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Ingo Molnar <mingo@kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Josh Poimboeuf <jpoimboe@redhat.com>,
        "H. Peter Anvin" <hpa@zytor.com>, Kees Cook <keescook@chromium.org>
Subject: Re: [RFC PATCH v2 2/6] x86/arch_prctl: add ARCH_GET_NOPTI and
 ARCH_SET_NOPTI to enable/disable PTI
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On Tue, Jan 09, 2018 at 01:26:57PM -0800, Andy Lutomirski wrote:
> 2.Turning off PTI is, in general, a terrible idea.  It totally breaks
> any semblance of a security model on a Meltdown-affected CPU.  So I
> think we should require CAP_SYS_RAWIO *and* that the system is booted
> with pti=allow_optout or something like that.

Uhh, I like that.

Maybe also taint the kernel ...

-- 
Regards/Gruss,
    Boris.

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