Date: Tue, 8 Mar 2016 21:44:58 +0100
From: Jiri Olsa <jolsa@redhat.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>, Wang Nan <wangnan0@huawei.com>,
        mingo@redhat.com, linux-kernel@vger.kernel.org,
        He Kuang <hekuang@huawei.com>, Alexei Starovoitov <ast@kernel.org>,
        Arnaldo Carvalho de Melo <acme@redhat.com>,
        Brendan Gregg <brendan.d.gregg@gmail.com>,
        Jiri Olsa <jolsa@kernel.org>,
        Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
        Namhyung Kim <namhyung@kernel.org>, Zefan Li <lizefan@huawei.com>,
        pi3orama@163.com
Subject: Re: [RESEND PATCH 0/5] perf core: Support overwrite ring buffer
Message-ID: <20160308204458.GD7897@krava.redhat.com>
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 <20160308135759.GH6356@twins.programming.kicks-ass.net>
 <20160308195642.GC7897@krava.redhat.com>
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On Tue, Mar 08, 2016 at 09:07:46PM +0100, Peter Zijlstra wrote:
> On Tue, Mar 08, 2016 at 08:56:42PM +0100, Jiri Olsa wrote:
> > > # cat go-fuzz.sh
> > > #!/bin/bash
> > > 
> > > echo 1 > /proc/sys/kernel/traceoff_on_warning
> > > echo 1 > /debug/tracing/options/stacktrace
> > > echo 1 > /debug/tracing/events/sched/enable
> > 
> > are you running this under root?
> 
> Of course ;-) I'm not even sure these machines have a user account.
> 
> Also, what's the point of fuzzing if half your 'fun' options return
> -EPERM.

IIRC the perf fuzzer (one from Vince) could screw your machine having
it run under root

jirka