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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Thu, 11 Jan 2018 10:26:52 -0800
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Subject: Re: [RFC PATCH v2 6/6] x86/entry/pti: don't switch PGD on when
 pti_disable is set
To: Willy Tarreau <w@1wt.eu>
Cc: Andy Lutomirski <luto@kernel.org>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Peter Zijlstra <peterz@infradead.org>,
        LKML <linux-kernel@vger.kernel.org>, X86 ML <x86@kernel.org>,
        Borislav Petkov <bp@alien8.de>,
        Brian Gerst <brgerst@gmail.com>,
        Ingo Molnar <mingo@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Josh Poimboeuf <jpoimboe@redhat.com>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Kees Cook <keescook@chromium.org>
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On Thu, Jan 11, 2018 at 10:25 AM, Linus Torvalds
<torvalds@linux-foundation.org> wrote:
>
> The other case may be the CLONE_NEW* operations. I *think* they are
> noops as far as PTI settings would be, but I think people should think
> about them.

Oh, and yes, I think the npti flag should also break ptrace(). I do
agree with Andy that it's a "capability", although I do not think it
should actually be implemented as one.

                   Linus