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Date: Mon, 15 Jan 2018 14:30:32 -0600
From: Josh Poimboeuf <jpoimboe@redhat.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>,
        David Woodhouse <dwmw2@infradead.org>,
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        Paolo Bonzini <pbonzini@redhat.com>,
        Jun Nakajima <jun.nakajima@intel.com>,
        Asit Mallick <asit.k.mallick@intel.com>
Subject: Re: [PATCH 2/4] objtool: Implement jump_assert for _static_cpu_has()
Message-ID: <20180115203032.rykendkdrxtjrtf7@treble>
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On Mon, Jan 15, 2018 at 09:15:45PM +0100, Peter Zijlstra wrote:
> On Mon, Jan 15, 2018 at 01:11:51PM -0600, Josh Poimboeuf wrote:
> > Well, to clarify, it would solve _some_ of the problem.  Maybe even most
> > of the problem.  We'd still need to special-case jump labels in objtool
> > (like in 1/4), but that's probably not a big deal.
> > 
> > So, contradicting my previous answer here... yes, it would help.
> 
> OK, saves me from having to argue otherwise. My argument would've been
> that jump labels are fully described and don't need further annotation.
> 
> Yes, Boris' proposal would certainly help with the alternative stuff.

Fair enough.  So either annotating _static_cpu_has() or adding an
alt_instr flag works for me.

-- 
Josh