Re: [PATCH v1 0/4] Enable LBR for the guest

[Andi Kleen]

On Mon, Sep 25, 2017 at 12:44:52PM +0800, Wei Wang wrote:
> This patch series enables the Last Branch Recording feature for the
> guest. Instead of trapping each LBR stack MSR access, the MSRs are
> passthroughed to the guest. Those MSRs are switched (i.e. load and
> saved) on VMExit and VMEntry.
> 
> Test:
> Try "perf record -b ./test_program" on guest.

I don't see where you expose the PERF capabilities MSR? 

That's normally needed for LBR too to report the version
number.

-Andi