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Date: Fri, 19 Oct 2012 10:20:18 -0700
From: Andi Kleen <ak@linux.intel.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>, LKML <linux-kernel@vger.kernel.org>,
        "mingo@elte.hu" <mingo@elte.hu>,
        Arnaldo Carvalho de Melo <acme@redhat.com>,
        Jiri Olsa <jolsa@redhat.com>
Subject: Re: [PATCH 2/2] perf: SNB exclusive PMU access for
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> > > This isn't limited to admin, right? So the above turns into a DoS on the
> > > console.
> > >
> > Ok, so how about a WARN_ON_ONCE() instead?
> 
> That should be fine I guess ;-)

imho there is need for a generic mechanism to return an error string
to the user program without such hacks.

-Andi

-- 
ak@linux.intel.com -- Speaking for myself only