2 files changed, 10 insertions, 1 deletions

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 552be51e4d84..9f72a443455b 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1564,6 +1564,7 @@ int kvm_dev_ioctl_check_extension(long ext)
         case KVM_CAP_VCPU_EVENTS:
         case KVM_CAP_HYPERV:
         case KVM_CAP_HYPERV_VAPIC:
+        case KVM_CAP_HYPERV_SPIN:
                 r = 1;
                 break;
         case KVM_CAP_COALESCED_MMIO:
@@ -3827,7 +3828,14 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
 
         trace_kvm_hv_hypercall(code, fast, rep_cnt, rep_idx, ingpa, outgpa);
 
-        res = HV_STATUS_INVALID_HYPERCALL_CODE;
+        switch (code) {
+        case HV_X64_HV_NOTIFY_LONG_SPIN_WAIT:
+                kvm_vcpu_on_spin(vcpu);
+                break;
+        default:
+                res = HV_STATUS_INVALID_HYPERCALL_CODE;
+                break;
+        }
 
         ret = res | (((u64)rep_done & 0xfff) << 32);
         if (longmode) {
diff --git a/include/linux/kvm.h b/include/linux/kvm.h
index 5ce61738dc30..4c4937e7f65f 100644
--- a/include/linux/kvm.h
+++ b/include/linux/kvm.h
@@ -499,6 +499,7 @@ struct kvm_ioeventfd {
 #define KVM_CAP_PPC_SEGSTATE 43
 #define KVM_CAP_HYPERV 44
 #define KVM_CAP_HYPERV_VAPIC 45
+#define KVM_CAP_HYPERV_SPIN 46
 
 #ifdef KVM_CAP_IRQ_ROUTING