Messages in this thread | | | Date | Fri, 14 Mar 2014 06:56:52 -0700 | From | Andi Kleen <> | Subject | Re: [PATCH] perf/x86/intel: Use rdmsrl_safe when initializing RAPL PMU. |
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On Fri, Mar 14, 2014 at 09:44:29AM +0100, Peter Zijlstra wrote: > On Thu, Mar 13, 2014 at 12:36:26PM -0700, Venkatesh Srinivas wrote: > > CPUs which should support the RAPL counters according to > > Family/Model/Stepping may still issue #GP when attempting to access > > the RAPL MSRs. This may happen when Linux is running under KVM and > > we are passing-through host F/M/S data, for example. Use rdmsrl_safe > > to first access the RAPL_POWER_UNIT MSR; if this fails, do not > > attempt to use this PMU. > > This kvm thing is getting tedious :-(
It sounds bogus to me too, VMs are supposed to return 0 on reading unknown MSRs, no #GP.
-Andi
-- ak@linux.intel.com -- Speaking for myself only
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