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Date: Mon, 29 Sep 2014 13:42:12 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Andi Kleen <andi@firstfloor.org>
Cc: dave@sr71.net, linux-kernel@vger.kernel.org, mingo@kernel.org,
        eranian@google.com, x86@kernel.org, Andi Kleen <ak@linux.intel.com>
Subject: Re: [PATCH 1/2] Use faster check for modules in backtrace on 64bit
Message-ID: <20140929114212.GG5430@worktop>
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On Fri, Sep 26, 2014 at 04:31:16PM -0700, Andi Kleen wrote:
> 
> This has the (small) potential to get a false positive on a pointer to a
> data segment in a module.  However since we also use the frame pointer
> chain as initial sanity check I think the danger of this is very low.
> 

So this has come up several times; and the answer has always been, why
not make the __module_address() thing a rb-tree instead of a linear
loop. So I suppose I'll ask that again, why not?