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Date: Tue, 18 Aug 2015 04:24:28 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Andy Lutomirski <luto@amacapital.net>
Cc: =?iso-8859-1?Q?Fr=E9d=E9ric?= Weisbecker <fweisbec@gmail.com>,
        Borislav Petkov <bp@alien8.de>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: Can I use static keys from asm?
Message-ID: <20150818022428.GH20948@worktop>
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On Mon, Aug 17, 2015 at 06:34:08PM -0700, Andy Lutomirski wrote:
> 2. Context tracking enabled in config but completely disabled at
> runtime.  Distros do this.  I want to nop out the context tracking
> hooks.  We have a static_key for this, but half the hooks are in asm.

> To unsuck case 2, static keys in asm would help.  Can I do that?  It
> would be even better if I could do that in 4.3.

I think Anton did a number of patches to enable static_key usage in asm
on PowerPC. x86 would need a bit of work but nothing makes it
fundamentally impossible.