Re: [PATCH v2 3/4] Add support for AMD Core Perf Extension in guest

From: Natarajan, Janakarajan
Date: Thu Nov 16 2017 - 12:14:15 EST


On 11/15/2017 1:07 PM, Borislav Petkov wrote:
On Wed, Nov 15, 2017 at 01:04:03PM -0600, Natarajan, Janakarajan wrote:
So, when the amd_pmu_init is called, a query to guest_cpuid_family() gives a
value of -1.
And that is because...? And it can be fixed to give the proper guest family I
presume ...?

Qemu initially creates a vcpu with KVM_CREATE_VCPU which in kvm initializes the pmu. Later on
the cpuid is set using KVM_SET_CPUID2 which sets all the cpuid entries in kvm and the pmu refresh is called.