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Date: Thu, 13 Jul 2017 07:21:15 -0500
From: Josh Poimboeuf <jpoimboe@redhat.com>
To: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>,
        Andres Freund <andres@anarazel.de>, x86@kernel.org,
        linux-kernel@vger.kernel.org, live-patching@vger.kernel.org,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Andy Lutomirski <luto@kernel.org>, Jiri Slaby <jslaby@suse.cz>,
        "H. Peter Anvin" <hpa@zytor.com>, Mike Galbraith <efault@gmx.de>,
        Jiri Olsa <jolsa@redhat.com>,
        Arnaldo Carvalho de Melo <acme@infradead.org>,
        Namhyung Kim <namhyung@kernel.org>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>
Subject: Re: [PATCH v3 00/10] x86: ORC unwinder (previously undwarf)
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On Thu, Jul 13, 2017 at 07:17:55AM -0500, Josh Poimboeuf wrote:
> BTW, while we're throwing out ideas for this, here's another idea,
> though it's almost certainly not a good one :-)
> 
> For user space stack unwinding, the kernel could emulate what the kernel
> 'guess' unwinder does by scanning the user space stack and returning all
> the text addresses it finds.
> 
> The results wouldn't be 100% accurate, but they could end up being
> useful over time.

And to expound further on the bad idea, maybe the "bad" addresses could
be filtered out somehow in post-processing (insert lots of hand waving).

-- 
Josh