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Date:   Thu, 1 Nov 2018 19:13:47 +0900
From:   Masami Hiramatsu <mhiramat@kernel.org>
To:     Aleksa Sarai <cyphar@cyphar.com>
Cc:     Steven Rostedt <rostedt@goodmis.org>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com>,
        Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>,
        "David S. Miller" <davem@davemloft.net>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Jiri Olsa <jolsa@redhat.com>,
        Namhyung Kim <namhyung@kernel.org>,
        Brendan Gregg <bgregg@netflix.com>,
        Christian Brauner <christian@brauner.io>,
        Aleksa Sarai <asarai@suse.de>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] kretprobe: produce sane stack traces
Message-Id: <20181101191347.74eadff4a5d1fab2d79d7efe@kernel.org>
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        <20181031090317.4e211fdd@vmware.local.home>
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On Thu, 1 Nov 2018 00:39:12 +1100
Aleksa Sarai <cyphar@cyphar.com> wrote:

> On 2018-10-31, Steven Rostedt <rostedt@goodmis.org> wrote:
> > > Anyway, until that merge happens, this patch looks good to avoid
> > > this issue for generic solution (e.g. for the arch which doesn't
> > > supports retstack).
> > 
> > I think its time to come up with an algorithm that makes function graph
> > work with multiple users, and have kretprobes be able to hook into it
> > just like kprobes hooks into function tracer.
> > 
> > I have some ideas on how to get this done, and will try to have an RFC
> > patch set ready by plumbers.
> 
> Should I continue working on this patchset?

Yes, until we finally introduce Steven's algorithm on all arch (yeah, we still
have some archs which don't support graph-tracer but supports kprobes),
I think your patch is the best fix for this issue.

Thank you,

-- 
Masami Hiramatsu <mhiramat@kernel.org>