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Date:   Thu, 22 Nov 2018 15:32:10 +0100
From:   Oleg Nesterov <oleg@redhat.com>
To:     Masami Hiramatsu <mhiramat@kernel.org>
Cc:     Tom Zanussi <tom.zanussi@linux.intel.com>,
        Namhyung Kim <namhyung@kernel.org>,
        "zhangwei(Jovi)" <jovi.zhangwei@huawei.com>,
        Srikar Dronamraju <srikar@linux.vnet.ibm.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        linux-kernel@vger.kernel.org
Subject: Re: uprobe support mix of ftrace and perf
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Hi Masami,

On 11/20, Masami Hiramatsu wrote:
>
> Hello Oleg,
>
> I have a question about the (revert) commit 48212542067a
> ("tracing/uprobes: Revert "Support mix of ftrace and perf""). I found
> this limitation still exists on uprobe events.

Yes...

> Would you have any plan or idea to fix this issue? I thought this revert
> patch was a tentative one, and should be fixed afterwards.

To be honest, I was going to fix this "soon" many years ago, but today I simply
can't recall how this code actually works and what exactly we need to do to
support ftrace/perf at the same time...

I'll try to read this code later, but I can't promise anything :/

Oleg.