Re: [PATCH v2 3/7] KVM: selftests: Test unavailable event filters are rejected

Sean Christopherson
2023-05-25T17:46:53Z

On Thu, Apr 20, 2023, Jinrong Liang wrote:
> From: Jinrong Liang <cloudliang@tencent.com>
>
> From: Jinrong Liang <cloudliang@tencent.com>
>
> Adds unsupported input test cases for PMU filter. Specifically,
> it tests the input of unsupported "action" values, unsupported
> "flags" values, and unsupported "nevents" values, which should
> all return an error, as they are currently unsupported by the
> filter. Additionally, the patch tests setting non-exist fixed
> counters in the fixed bitmap doesn't fail.
>
> This change aims to improve the testing of the PMU filter and
> ensure that it functions correctly in all supported use cases.
> The patch has been tested and verified to function correctly.
>
> Signed-off-by: Jinrong Liang <cloudliang@tencent.com>
> ---
> .../kvm/x86_64/pmu_event_filter_test.c | 52 +++++++++++++++++++
> 1 file changed, 52 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 4e87eea6986b..a3d5c30ce914 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
> @@ -27,6 +27,10 @@
> #define ARCH_PERFMON_BRANCHES_RETIRED 5
>
> #define NUM_BRANCHES 42
> +#define FIXED_CTR_NUM_MASK GENMASK_ULL(4, 0)
> +#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
> @@ -743,10 +747,22 @@ static int run_filter_test(struct kvm_vcpu *vcpu, const uint64_t *events,
> return r;
> }
>
> +static uint8_t get_kvm_supported_fixed_num(void)
> +{
> + const struct kvm_cpuid_entry2 *kvm_entry;
> +
> + if (host_cpu_is_amd)
> + return 0;
> +
> + kvm_entry = get_cpuid_entry(kvm_get_supported_cpuid(), 0xa, 0);
> + return kvm_entry->edx & FIXED_CTR_NUM_MASK;

Ah, I got ahead of myself. This is where the KVM_X86_PROPERTY comes in.