[PATCH v2 11/12] KVM: selftests / xen: don't explicitly set the vcpu_info address

From: Paul Durrant
Date: Mon Sep 18 2023 - 07:43:58 EST


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.

Signed-off-by: Paul Durrant <pdurrant@xxxxxxxxxx>
---
Cc: Sean Christopherson <seanjc@xxxxxxxxxx>
Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Cc: David Woodhouse <dwmw2@xxxxxxxxxxxxx>

v2:
- New in this version.
---
tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)

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 fa829d6e0848..d1c88deec0b2 100644
--- a/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c
+++ b/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c
@@ -550,11 +550,13 @@ int main(int argc, char *argv[])
vcpu_ioctl(vcpu, KVM_XEN_VCPU_SET_ATTR, &vid);
}

- struct kvm_xen_vcpu_attr vi = {
- .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) {
+ struct kvm_xen_vcpu_attr vi = {
+ .type = KVM_XEN_VCPU_ATTR_TYPE_VCPU_INFO,
+ .u.gpa = VCPU_INFO_ADDR,
+ };
+ vcpu_ioctl(vcpu, KVM_XEN_VCPU_SET_ATTR, &vi);
+ }

struct kvm_xen_vcpu_attr pvclock = {
.type = KVM_XEN_VCPU_ATTR_TYPE_VCPU_TIME_INFO,
--
2.39.2