Re: [PATCH] perf/x86/intel: Use rdmsrl_safe when initializing RAPL PMU.

Peter Zijlstra
2014-04-23T15:09:20Z

On Wed, Apr 23, 2014 at 04:49:55PM +0200, Stephane Eranian wrote:
> On your machine, booted with 3.15-rc2, do you have /sys/devices/power?
> If not, and you have at least an SNB, you should have RAPL and that
> RAPL_UNIT MSR.
>
> Proof is that if you read that MSR using /dev/cpu/msr it works just fine:
> # modprobe msr
> # rdmsr 0x606
> a1003
>
> So something is broken somewhere.

I've not got SNB+ class hardware (for testing). But I believe you that
there's something funny, I just do not understanding how *msr_safe()
could cause this.