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Message-ID: <1516280587.4937.128.camel@infradead.org>
Subject: Re: [PATCH v1 tip/master 0/3] kprobes/x86: retpoline: Fix kprobes
 for retpoline
From:   David Woodhouse <dwmw2@infradead.org>
To:     Andi Kleen <ak@linux.intel.com>,
        Masami Hiramatsu <mhiramat@kernel.org>
Cc:     Ingo Molnar <mingo@kernel.org>, linux-kernel@vger.kernel.org,
        Greg Kroah-Hartman <gregkh@linux-foundation.org>,
        Arjan van de Ven <arjan@linux.intel.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        "H . Peter Anvin" <hpa@zytor.com>
In-Reply-To: <20180118130157.GE7844@tassilo.jf.intel.com>
References: <151627684798.24682.2979775081582774869.stgit@devbox>
         <20180118130157.GE7844@tassilo.jf.intel.com>
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Date:   Thu, 18 Jan 2018 14:03:07 +0100
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On Thu, 2018-01-18 at 05:01 -0800, Andi Kleen wrote:
> >=20
> > Side effect: [1/3] will move __x86_indirect_thunk_* functions
> > in kernel text area. Of course those functions were in the
> > .text area, but placed in right after _etext. This just moves
> > it right before the _etext.
> I assume you tested that with page table isolation on?
>=20
> The thunks need to be accessible from the trampoline.

I thought we put it inline in the trampoline.
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