Extend kvm_clock_test to enable KVM steal time and verify that a KVM_SET_CLOCK adjustment with KVM_CLOCK_REALTIME also advances the guest's steal time when the realtime value is in the past.
For the negative realtime-offset case, verify that the observed steal time delta is at least the downtime injected through KVM_SET_CLOCK. Signed-off-by: Dongli Zhang <[email protected]> --- .../selftests/kvm/x86/kvm_clock_test.c | 42 +++++++++++++++---- 1 file changed, 34 insertions(+), 8 deletions(-) diff --git a/tools/testing/selftests/kvm/x86/kvm_clock_test.c b/tools/testing/selftests/kvm/x86/kvm_clock_test.c index 5ad4aeb8e373..7e0f00f21144 100644 --- a/tools/testing/selftests/kvm/x86/kvm_clock_test.c +++ b/tools/testing/selftests/kvm/x86/kvm_clock_test.c @@ -28,16 +28,20 @@ static struct test_case test_cases[] = { { .kvmclock_base = 0, .realtime_offset = 180 * NSEC_PER_SEC }, }; -#define GUEST_SYNC_CLOCK(__stage, __val) \ - GUEST_SYNC_ARGS(__stage, __val, 0, 0, 0) +#define GUEST_SYNC_CLOCK(__stage, __clock, __steal) \ + GUEST_SYNC_ARGS(__stage, __clock, __steal, 0, 0) -static void guest_main(gpa_t pvti_pa, struct pvclock_vcpu_time_info *pvti) +static void guest_main(gpa_t pvti_pa, struct pvclock_vcpu_time_info *pvti, + gpa_t st_pa, struct kvm_steal_time *st) { int i; wrmsr(MSR_KVM_SYSTEM_TIME_NEW, pvti_pa | KVM_MSR_ENABLED); + wrmsr(MSR_KVM_STEAL_TIME, st_pa | KVM_MSR_ENABLED); + for (i = 0; i < ARRAY_SIZE(test_cases); i++) - GUEST_SYNC_CLOCK(i, __pvclock_read_cycles(pvti, rdtsc())); + GUEST_SYNC_CLOCK(i, __pvclock_read_cycles(pvti, rdtsc()), + READ_ONCE(st->steal)); } #define EXPECTED_FLAGS (KVM_CLOCK_REALTIME | KVM_CLOCK_HOST_TSC) @@ -50,11 +54,13 @@ static inline void assert_flags(struct kvm_clock_data *data) } static void handle_sync(struct ucall *uc, struct kvm_clock_data *start, - struct kvm_clock_data *end) + struct kvm_clock_data *end, + struct test_case *test_case, u64 *last_steal) { - u64 obs, exp_lo, exp_hi; + u64 obs, exp_lo, exp_hi, obs_steal; obs = uc->args[2]; + obs_steal = uc->args[3]; exp_lo = start->clock; exp_hi = end->clock; @@ -67,6 +73,18 @@ static void handle_sync(struct ucall *uc, struct kvm_clock_data *start, pr_info("kvm-clock value: %"PRIu64" expected range [%"PRIu64", %"PRIu64"]\n", obs, exp_lo, exp_hi); + + if (test_case->realtime_offset < 0) { + u64 min_downtime = -test_case->realtime_offset; + + TEST_ASSERT(obs_steal >= *last_steal && + obs_steal - *last_steal >= min_downtime, + "unexpected steal values: obs=%"PRIu64 + " last=%"PRIu64" min_downtime=%"PRIu64, + obs_steal, *last_steal, min_downtime); + } + + *last_steal = obs_steal; } static void handle_abort(struct ucall *uc) @@ -106,6 +124,7 @@ static void enter_guest(struct kvm_vcpu *vcpu) { struct kvm_clock_data start, end; struct kvm_vm *vm = vcpu->vm; + u64 last_steal = 0; struct ucall uc; int i; @@ -121,7 +140,8 @@ static void enter_guest(struct kvm_vcpu *vcpu) switch (get_ucall(vcpu, &uc)) { case UCALL_SYNC: - handle_sync(&uc, &start, &end); + handle_sync(&uc, &start, &end, + &test_cases[i], &last_steal); break; case UCALL_ABORT: handle_abort(&uc); @@ -137,6 +157,8 @@ int main(void) struct kvm_vcpu *vcpu; gva_t pvti_gva; gpa_t pvti_gpa; + gva_t st_gva; + gpa_t st_gpa; struct kvm_vm *vm; int flags; @@ -144,12 +166,16 @@ int main(void) TEST_REQUIRE(flags & KVM_CLOCK_REALTIME); TEST_REQUIRE(sys_clocksource_is_based_on_tsc()); + TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_KVM_STEAL_TIME)); vm = vm_create_with_one_vcpu(&vcpu, guest_main); pvti_gva = vm_alloc(vm, getpagesize(), 0x10000); pvti_gpa = addr_gva2gpa(vm, pvti_gva); - vcpu_args_set(vcpu, 2, pvti_gpa, pvti_gva); + st_gva = vm_alloc(vm, getpagesize(), 0x20000); + st_gpa = addr_gva2gpa(vm, st_gva); + memset(addr_gva2hva(vm, st_gva), 0, getpagesize()); + vcpu_args_set(vcpu, 4, pvti_gpa, pvti_gva, st_gpa, st_gva); enter_guest(vcpu); kvm_vm_free(vm); -- 2.39.3
