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Date:   Thu, 1 Nov 2018 09:22:44 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Aleksa Sarai <cyphar@cyphar.com>
Cc:     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: <20181101092244.2ad82f18@vmware.local.home>
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On Thu, 1 Nov 2018 21:49:48 +1100
Aleksa Sarai <cyphar@cyphar.com> wrote:


> > > 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.  

Agreed.

> 
> Thanks, I just sent a v3.

Thanks. Hopefully I can take a look at it today or tomorrow. I'm still
trying to get home (sitting at yet another airport as I write this).

> 
> Though, even with Steven's hooking of kprobes I think you'd still need
> to stash away the stack trace somewhere (or am I misunderstanding the
> proposal?).

I'll start working on it and then we can see what is needed when there
is actual code. I need to probably change the func graph generic
interface which will require changes in all the archs that support
function graph tracer.

-- Steve