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Date: Mon, 27 Nov 2017 13:49:52 +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>,
        Andy Lutomirski <luto@kernel.org>, Ingo Molnar <mingo@kernel.org>,
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        michael.schwarz@iaik.tugraz.at, moritz.lipp@iaik.tugraz.at,
        richard.fellner@student.tugraz.at
Subject: Re: [patch V2 5/5] x86/kaiser: Add boottime disable switch
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On Mon, Nov 27, 2017 at 12:50:45PM +0100, Thomas Gleixner wrote:
> On Mon, 27 Nov 2017, Peter Zijlstra wrote:
> > On Mon, Nov 27, 2017 at 10:48:46AM +0100, Peter Zijlstra wrote:

> > > So in patch 15 Andy notes that we should probably also disable the
> > > SYSCALL trampoline when we disable KAISER.
> > > 
> > >   https://lkml.kernel.org/r/20171124172411.19476-16-mingo@kernel.org
> > 
> > Could be a simple as this.. but I've not tested.
> 
> That's only one part of it. I think we need to fiddle with the exit side as
> well.

So I assumed that the patches were bisectable. From that I figured the
exit path (patch 14 in that set) would work either way.