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Date: Thu, 4 Jan 2018 01:19:22 +0100 (CET)
From: Jiri Kosina <jikos@kernel.org>
To: Andi Kleen <andi@firstfloor.org>
cc: Thomas Gleixner <tglx@linutronix.de>,
        Linus Torvalds <torvalds@linux-foundation.org>,
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        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Dave Hansen <dave.hansen@intel.com>
Subject: Re: Avoid speculative indirect calls in kernel
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On Wed, 3 Jan 2018, Andi Kleen wrote:

> > It should be a CPU_BUG bit as we have for the other mess. And that can be
> > used for patching.
> 
> It has to be done at compile time because it requires a compiler option.

If gcc anotates indirect calls/jumps in a way that we could patch them 
using alternatives in runtime, that'd be enough.

-- 
Jiri Kosina
SUSE Labs