1 files changed, 14 insertions, 0 deletions
diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 7644f6dc2c..40c3091edf 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -4145,6 +4145,20 @@ static Property x86_cpu_properties[] = {
                      false),
     DEFINE_PROP_BOOL("vmware-cpuid-freq", X86CPU, vmware_cpuid_freq, true),
     DEFINE_PROP_BOOL("tcg-cpuid", X86CPU, expose_tcg, true),
+
+    /*
+     * From "Requirements for Implementing the Microsoft
+     * Hypervisor Interface":
+     * https://docs.microsoft.com/en-us/virtualization/hyper-v-on-windows/reference/tlfs
+     *
+     * "Starting with Windows Server 2012 and Windows 8, if
+     * CPUID.40000005.EAX contains a value of -1, Windows assumes that
+     * the hypervisor imposes no specific limit to the number of VPs.
+     * In this case, Windows Server 2012 guest VMs may use more than
+     * 64 VPs, up to the maximum supported number of processors applicable
+     * to the specific Windows version being used."
+     */
+    DEFINE_PROP_INT32("x-hv-max-vps", X86CPU, hv_max_vps, -1),
     DEFINE_PROP_END_OF_LIST()
 };