[PATCH v3 2/4] KVM: selftests: Test unavailable event filters are rejected

From: Jinrong Liang
Date: Wed Jun 07 2023 - 08:38:02 EST


From: Jinrong Liang <cloudliang@xxxxxxxxxxx>

This commit adds test cases for unsupported input values in the
PMU event filter. The tests cover unsupported "action" values,
unsupported "flags" values, and unsupported "nevents" values.
All these cases should return an error, as they are currently
not supported by the filter. Additionally, the patch tests setting
non-exist fixed counters in the fixed bitmap doesn't fail.

Signed-off-by: Jinrong Liang <cloudliang@xxxxxxxxxxx>
---
.../kvm/x86_64/pmu_event_filter_test.c | 48 +++++++++++++++++--
1 file changed, 45 insertions(+), 3 deletions(-)

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 26f674c32cde..7555e0f4290c 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
@@ -11,9 +11,7 @@
*/

#define _GNU_SOURCE /* for program_invocation_short_name */
-#include "test_util.h"
-#include "kvm_util.h"
-#include "processor.h"
+#include "pmu.h"

/*
* In lieu of copying perf_event.h into tools...
@@ -32,6 +30,10 @@
#define MAX_FILTER_EVENTS 300
#define MAX_TEST_EVENTS 10

+#define PMU_EVENT_FILTER_INVALID_ACTION (KVM_PMU_EVENT_DENY + 1)
+#define PMU_EVENT_FILTER_INVALID_FLAGS (KVM_PMU_EVENT_FLAG_MASKED_EVENTS + 1)
+#define PMU_EVENT_FILTER_INVALID_NEVENTS (MAX_FILTER_EVENTS + 1)
+
/*
* This is how the event selector and unit mask are stored in an AMD
* core performance event-select register. Intel's format is similar,
@@ -762,6 +764,7 @@ static void test_filter_ioctl(struct kvm_vcpu *vcpu)
{
uint64_t e = ~0ul;
int r;
+ struct __kvm_pmu_event_filter f;

/*
* Unfortunately having invalid bits set in event data is expected to
@@ -780,6 +783,45 @@ static void test_filter_ioctl(struct kvm_vcpu *vcpu)
KVM_PMU_EVENT_FLAG_MASKED_EVENTS,
KVM_PMU_EVENT_ALLOW);
TEST_ASSERT(r == 0, "Valid PMU Event Filter is failing");
+
+ /*
+ * Testing unsupported "action" input values should return an error.
+ * Currently, only values 0 or 1 are supported.
+ */
+ f = base_event_filter;
+ f.action = PMU_EVENT_FILTER_INVALID_ACTION;
+ r = do_vcpu_set_pmu_event_filter(vcpu, &f);
+ TEST_ASSERT(r != 0, "Set invalid action is expected to fail.");
+
+ /*
+ * Testing unsupported "flags" input values should return an error.
+ * Currently, only values 0 or 1 are supported.
+ */
+ f = base_event_filter;
+ f.flags = PMU_EVENT_FILTER_INVALID_FLAGS;
+ r = do_vcpu_set_pmu_event_filter(vcpu, &f);
+ TEST_ASSERT(r != 0, "Set invalid flags is expected to fail.");
+
+ /*
+ * Testing unsupported "nevents" input values should return an error.
+ * Currently, only values less than or equal to
+ * MAX_FILTER_EVENTS are supported.
+ */
+ f = base_event_filter;
+ f.nevents = PMU_EVENT_FILTER_INVALID_NEVENTS;
+ r = do_vcpu_set_pmu_event_filter(vcpu, &f);
+ TEST_ASSERT(r != 0,
+ "Setting PMU event filters that exceeds the maximum supported value should fail");
+
+ /*
+ * In this case, setting non-exist fixed counters in the fixed bitmap
+ * doesn't fail.
+ */
+ f = base_event_filter;
+ f.fixed_counter_bitmap = ~GENMASK_ULL(X86_INTEL_MAX_FIXED_CTR_NUM, 0);
+ r = do_vcpu_set_pmu_event_filter(vcpu, &f);
+ TEST_ASSERT(r == 0,
+ "Setting invalid or non-exist fixed cunters in the fixed bitmap fail.");
}

int main(int argc, char *argv[])
--
2.31.1