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Subject[PATCH v2 3/3] kvm/selftests: update tsc_msrs_test to cover KVM_X86_QUIRK_TSC_HOST_ACCESS
Date
Run the test once with quirk enabled and once disabled,
and adjust the expected values accordingly.

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
---
.../selftests/kvm/x86_64/tsc_msrs_test.c | 79 ++++++++++++++++---
1 file changed, 69 insertions(+), 10 deletions(-)

diff --git a/tools/testing/selftests/kvm/x86_64/tsc_msrs_test.c b/tools/testing/selftests/kvm/x86_64/tsc_msrs_test.c
index e357d8e222d47..3900c543a7ee1 100644
--- a/tools/testing/selftests/kvm/x86_64/tsc_msrs_test.c
+++ b/tools/testing/selftests/kvm/x86_64/tsc_msrs_test.c
@@ -79,8 +79,6 @@ static void run_vcpu(struct kvm_vm *vm, uint32_t vcpuid, int stage)
{
struct ucall uc;

- vcpu_args_set(vm, vcpuid, 1, vcpuid);
-
vcpu_ioctl(vm, vcpuid, KVM_RUN, NULL);

switch (get_ucall(vm, vcpuid, &uc)) {
@@ -101,7 +99,7 @@ static void run_vcpu(struct kvm_vm *vm, uint32_t vcpuid, int stage)
}
}

-int main(void)
+void run_test(bool quirk_disabled)
{
struct kvm_vm *vm;
uint64_t val;
@@ -109,6 +107,14 @@ int main(void)
vm = vm_create_default(VCPU_ID, 0, guest_code);

val = 0;
+ if (quirk_disabled) {
+ struct kvm_enable_cap cap = {
+ .cap = KVM_CAP_DISABLE_QUIRKS,
+ .args[0] = KVM_X86_QUIRK_TSC_HOST_ACCESS,
+ };
+ vm_enable_cap(vm, &cap);
+ }
+
ASSERT_EQ(rounded_host_rdmsr(MSR_IA32_TSC), val);
ASSERT_EQ(rounded_host_rdmsr(MSR_IA32_TSC_ADJUST), val);

@@ -124,20 +130,67 @@ int main(void)
ASSERT_EQ(rounded_host_rdmsr(MSR_IA32_TSC), val);
ASSERT_EQ(rounded_host_rdmsr(MSR_IA32_TSC_ADJUST), val);

- /*
- * Host: writes to MSR_IA32_TSC set the host-side offset
- * and therefore do not change MSR_IA32_TSC_ADJUST.
- */
- vcpu_set_msr(vm, 0, MSR_IA32_TSC, HOST_ADJUST + val);
+ if (quirk_disabled) {
+ struct kvm_tsc_state state = {
+ .tsc = HOST_ADJUST + val,
+ .flags = 0
+ };
+ vcpu_ioctl(vm, VCPU_ID, KVM_SET_TSC_STATE, &state);
+ } else {
+ /*
+ * Host: writes to MSR_IA32_TSC set the host-side offset
+ * and therefore do not change MSR_IA32_TSC_ADJUST
+ */
+ vcpu_set_msr(vm, 0, MSR_IA32_TSC, HOST_ADJUST + val);
+ }
+
ASSERT_EQ(rounded_host_rdmsr(MSR_IA32_TSC), HOST_ADJUST + val);
ASSERT_EQ(rounded_host_rdmsr(MSR_IA32_TSC_ADJUST), val);
+
+ if (quirk_disabled) {
+ /*
+ * Host: writes to MSR_IA32_TSC work like in the guest
+ * when quirk is disabled
+ */
+ vcpu_set_msr(vm, 0, MSR_IA32_TSC, val);
+ ASSERT_EQ(rounded_host_rdmsr(MSR_IA32_TSC), val);
+ ASSERT_EQ(rounded_host_rdmsr(MSR_IA32_TSC_ADJUST), val - HOST_ADJUST);
+
+ /* Restore the value */
+ vcpu_set_msr(vm, 0, MSR_IA32_TSC, HOST_ADJUST + val);
+ ASSERT_EQ(rounded_host_rdmsr(MSR_IA32_TSC_ADJUST), val);
+ }
+
run_vcpu(vm, VCPU_ID, 3);

- /* Host: writes to MSR_IA32_TSC_ADJUST do not modify the TSC. */
+ /*
+ * Host: writes to MSR_IA32_TSC_ADJUST do not modify the TSC,
+ * (unless the quirk is disabled)
+ */
vcpu_set_msr(vm, 0, MSR_IA32_TSC_ADJUST, UNITY * 123456);
- ASSERT_EQ(rounded_host_rdmsr(MSR_IA32_TSC), HOST_ADJUST + val);
+ ASSERT_EQ(rounded_host_rdmsr(MSR_IA32_TSC),
+ quirk_disabled ? UNITY * 123456 + HOST_ADJUST : HOST_ADJUST + val);
ASSERT_EQ(vcpu_get_msr(vm, 0, MSR_IA32_TSC_ADJUST), UNITY * 123456);

+ if (quirk_disabled) {
+ /*
+ * Host: writes via KVM_SET_TSC_STATE
+ * to MSR_IA32_TSC and MSR_IA32_TSC_ADJUST can be done
+ * independently
+ */
+ struct kvm_tsc_state state = {
+ .tsc = UNITY * 42,
+ .tsc_adjust = UNITY * 42 - HOST_ADJUST,
+ .flags = KVM_TSC_STATE_TSC_ADJUST_VALID
+ };
+
+ vcpu_ioctl(vm, VCPU_ID, KVM_SET_TSC_STATE, &state);
+
+ ASSERT_EQ(rounded_host_rdmsr(MSR_IA32_TSC), UNITY * 42);
+ ASSERT_EQ(rounded_host_rdmsr(MSR_IA32_TSC_ADJUST),
+ UNITY * 42 - HOST_ADJUST);
+ }
+
/* Restore previous value. */
vcpu_set_msr(vm, 0, MSR_IA32_TSC_ADJUST, val);
ASSERT_EQ(rounded_host_rdmsr(MSR_IA32_TSC), HOST_ADJUST + val);
@@ -162,6 +215,12 @@ int main(void)
ASSERT_EQ(rounded_host_rdmsr(MSR_IA32_TSC_ADJUST), val - HOST_ADJUST);

kvm_vm_free(vm);
+}
+

+int main(void)
+{
+ run_test(false);
+ run_test(true);
return 0;
}
--
2.26.2
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