KVM: x86/pmu: Implement AMD mediated PMU requirements

Require host PMU version 2+ for AMD mediated PMU support, as
PERF_GLOBAL_CTRL and friends are hard requirements for the mediated PMU.

Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Co-developed-by: Mingwei Zhang <mizhang@google.com>
Signed-off-by: Mingwei Zhang <mizhang@google.com>
[sean: extract to separate patch, write changelog]
Reviewed-by: Sandipan Das <sandipan.das@amd.com>
Tested-by: Xudong Hao <xudong.hao@intel.com>
Tested-by: Manali Shukla <manali.shukla@amd.com>
Link: https://patch.msgid.link/20251206001720.468579-19-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

Author: sean-jc

arch/x86/kvm/svm/pmu.c

@@ -227,6 +227,11 @@ static void amd_pmu_init(struct kvm_vcpu *vcpu)
 	}
 }
 
+static bool amd_pmu_is_mediated_pmu_supported(struct x86_pmu_capability *host_pmu)
+{
+	return host_pmu->version >= 2;
+}
+
 struct kvm_pmu_ops amd_pmu_ops __initdata = {
 	.rdpmc_ecx_to_pmc = amd_rdpmc_ecx_to_pmc,
 	.msr_idx_to_pmc = amd_msr_idx_to_pmc,
@@ -236,6 +241,9 @@ struct kvm_pmu_ops amd_pmu_ops __initdata = {
 	.set_msr = amd_pmu_set_msr,
 	.refresh = amd_pmu_refresh,
 	.init = amd_pmu_init,
+
+	.is_mediated_pmu_supported = amd_pmu_is_mediated_pmu_supported,
+
 	.EVENTSEL_EVENT = AMD64_EVENTSEL_EVENT,
 	.MAX_NR_GP_COUNTERS = KVM_MAX_NR_AMD_GP_COUNTERS,
 	.MIN_NR_GP_COUNTERS = AMD64_NUM_COUNTERS,