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Date: Mon, 27 Nov 2017 10:57:37 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: LKML <linux-kernel@vger.kernel.org>,
        Dave Hansen <dave.hansen@linux.intel.com>,
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        michael.schwarz@iaik.tugraz.at, moritz.lipp@iaik.tugraz.at,
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Subject: Re: [patch V2 1/5] x86/kaiser: Respect disabled CPU features
Message-ID: <20171127095737.ocolhqaxsaboycwa@hirez.programming.kicks-ass.net>
References: <20171126231403.657575796@linutronix.de>
 <20171126232414.313869499@linutronix.de>
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On Mon, Nov 27, 2017 at 12:14:04AM +0100, Thomas Gleixner wrote:
> PAGE_NX and PAGE_GLOBAL might be not supported or disabled on the command
> line, but KAISER sets them unconditionally.

So KAISER is x86_64 only, right? AFAIK there is no x86_64 without NX
support. So would it not make sense to mandate NX for KAISER?, that is
instead of making "noexec" + KAISER work, make "noexec" kill KAISER +
emit a warning.