Messages in this thread | | | Date | Tue, 27 Aug 2013 10:13:30 -0400 | From | Dave Jones <> | Subject | Re: suspicious RCU usage (perf) |
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On Tue, Aug 27, 2013 at 07:58:12AM -0600, David Ahern wrote: > On 8/27/13 7:10 AM, Steven Rostedt wrote: > > On Mon, 26 Aug 2013 15:49:24 -0400 > > Dave Jones <davej@redhat.com> wrote: > > > > > >> > Do you have /sys/kernel/debug with access permissions? > >> > >> Ah, yeah, that'll be it. Good catch. > >> > >> Sorry for the false alarm Steve ;) > > > > Yeah, but it still does not explain how perf got started. Perf requires > > a sys_perf_event_open() call to run. > > Per Peter's response another option is the paranoia level: > > # perf event paranoia level: > # -1 - not paranoid at all > # 0 - disallow raw tracepoint access for unpriv > # 1 - disallow cpu events for unpriv > # 2 - disallow kernel profiling for unpriv > kernel.perf_event_paranoid = -1
This I have set to 1 on that box. (The default)
Dave
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