On a VM with PMU disabled via KVM_CAP_PMU_CONFIG, the PMU should not be
usable by the guest.
Signed-off-by: David Dunn <daviddunn@xxxxxxxxxx>
---
.../kvm/x86_64/pmu_event_filter_test.c | 33 +++++++++++++++++++
1 file changed, 33 insertions(+)
diff --git a/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c b/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c
index c715adcbd487..dc04a266b3ed 100644
--- a/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c
+++ b/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c
@@ -325,6 +325,37 @@ static void test_not_member_allow_list(struct kvm_vm *vm)
TEST_ASSERT(!count, "Disallowed PMU Event is counting");
}
+/*
+ * Verify KVM_CAP_PMU_DISABLE prevents the use of the PMU.
+ *
+ * Note that KVM_CAP_PMU_CAPABILITY must be invoked prior to creating VCPUs.
+ */
+static void test_pmu_config_disable(void (*guest_code)(void))
+{
+ int r;
+ struct kvm_vm *vm;
+ struct kvm_enable_cap cap = { 0 };
+
+ r = kvm_check_cap(KVM_CAP_PMU_CAPABILITY);
+ if (!(r & KVM_CAP_PMU_DISABLE))
+ return;
+
+ vm = vm_create_without_vcpus(VM_MODE_DEFAULT, DEFAULT_GUEST_PHY_PAGES);
+
+ cap.cap = KVM_CAP_PMU_CAPABILITY;
+ cap.args[0] = KVM_CAP_PMU_DISABLE;
+ TEST_ASSERT(!vm_enable_cap(vm, &cap), "Failed KVM_CAP_PMU_DISABLE.");
+
+ vm_vcpu_add_default(vm, VCPU_ID, guest_code);
+ vm_init_descriptor_tables(vm);
+ vcpu_init_descriptor_tables(vm, VCPU_ID);
+
+ TEST_ASSERT(!sanity_check_pmu(vm),
+ "Guest should not be able to use disabled PMU.");
+
+ kvm_vm_free(vm);
+}
+
/*
* Check for a non-zero PMU version, at least one general-purpose
* counter per logical processor, an EBX bit vector of length greater
@@ -430,5 +461,7 @@ int main(int argc, char *argv[])
kvm_vm_free(vm);
+ test_pmu_config_disable(guest_code);
+
return 0;
}
--
2.35.1.265.g69c8d7142f-goog
