From: Paul Durrant <pdurrant@xxxxxxxxxx> If the vCPU id is set and the shared_info is mapped using HVA then we can infer that KVM has the ability to use a default vcpu_info mapping. Hence we can stop setting the address of the vcpu_info structure. NOTE: We still explicitly set vcpu_info half way through testing (to point at exactly the place it already is) to make sure that setting the attribute does not fail. Signed-off-by: Paul Durrant <pdurrant@xxxxxxxxxx> --- Cc: Sean Christopherson <seanjc@xxxxxxxxxx> Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx> Cc: David Woodhouse <dwmw2@xxxxxxxxxxxxx> v3: - Add a guest sync point to set the vcpu_info attribute v2: - New in this version. --- .../testing/selftests/kvm/x86_64/xen_shinfo_test.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c b/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c index e786fa370140..7e74b3063437 100644 --- a/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c +++ b/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c @@ -68,6 +68,7 @@ enum { TEST_POLL_TIMEOUT, TEST_POLL_MASKED, TEST_POLL_WAKE, + SET_VCPU_INFO, TEST_TIMER_PAST, TEST_LOCKING_SEND_RACE, TEST_LOCKING_POLL_RACE, @@ -327,6 +328,10 @@ static void guest_code(void) GUEST_SYNC(TEST_POLL_WAKE); + /* Set the vcpu_info to point at exactly the place it already is to + * make sure the attribute is functional. */ + GUEST_SYNC(SET_VCPU_INFO); + /* A timer wake an *unmasked* port which should wake us with an * actual interrupt, while we're polling on a different port. */ ports[0]++; @@ -549,7 +554,10 @@ int main(int argc, char *argv[]) .type = KVM_XEN_VCPU_ATTR_TYPE_VCPU_INFO, .u.gpa = VCPU_INFO_ADDR, }; - vcpu_ioctl(vcpu, KVM_XEN_VCPU_SET_ATTR, &vi); + + if (!has_vcpu_id || !has_shinfo_hva) { + vcpu_ioctl(vcpu, KVM_XEN_VCPU_SET_ATTR, &vi); + } struct kvm_xen_vcpu_attr pvclock = { .type = KVM_XEN_VCPU_ATTR_TYPE_VCPU_TIME_INFO, @@ -903,6 +911,10 @@ int main(int argc, char *argv[]) alarm(1); break; + case SET_VCPU_INFO: + vcpu_ioctl(vcpu, KVM_XEN_VCPU_SET_ATTR, &vi); + break; + case TEST_TIMER_PAST: TEST_ASSERT(!evtchn_irq_expected, "Expected event channel IRQ but it didn't happen"); -- 2.39.2