diff --git a/docs/man/xl.cfg.5.pod.in b/docs/man/xl.cfg.5.pod.in
index 3467eae2cd..7cdb8595d3 100644
--- a/docs/man/xl.cfg.5.pod.in
+++ b/docs/man/xl.cfg.5.pod.in
@@ -2267,11 +2267,16 @@ explicitly have any limits on the number of Virtual processors a guest
 is allowed to bring up. It is strongly recommended to keep this enabled
 for guests with more than 64 vCPUs.
 
+=item B<cpu_hotplug>
+
+This set enables dynamic changes to Virtual processor states in Windows
+guests effectively allowing vCPU hotplug.
+
 =item B<defaults>
 
 This is a special value that enables the default set of groups, which
 is currently the B<base>, B<freq>, B<time_ref_count>, B<apic_assist>,
-B<crash_ctl>, B<stimer> and B<no_vp_limit> groups.
+B<crash_ctl>, B<stimer>, B<no_vp_limit> and B<cpu_hotplug> groups.
 
 =item B<all>
 
diff --git a/tools/include/libxl.h b/tools/include/libxl.h
index ee15c0495c..547ddd3085 100644
--- a/tools/include/libxl.h
+++ b/tools/include/libxl.h
@@ -457,6 +457,12 @@
  */
 #define LIBXL_HAVE_VIRIDIAN_NO_VP_LIMIT 1
 
+/*
+ * LIBXL_HAVE_VIRIDIAN_CPU_HOTPLUG indicates that the 'cpu_hotplug' value
+ * is present in the viridian enlightenment enumeration.
+ */
+#define LIBXL_HAVE_VIRIDIAN_CPU_HOTPLUG 1
+
 /*
  * LIBXL_HAVE_DEVICE_PCI_LIST_FREE indicates that the
  * libxl_device_pci_list_free() function is defined.
diff --git a/tools/libs/light/libxl_types.idl b/tools/libs/light/libxl_types.idl
index 087a3db6e2..37fe61f3ec 100644
--- a/tools/libs/light/libxl_types.idl
+++ b/tools/libs/light/libxl_types.idl
@@ -240,6 +240,7 @@ libxl_viridian_enlightenment = Enumeration("viridian_enlightenment", [
     (9, "hcall_ipi"),
     (10, "ex_processor_masks"),
     (11, "no_vp_limit"),
+    (12, "cpu_hotplug"),
     ])
 
 libxl_hdtype = Enumeration("hdtype", [
diff --git a/tools/libs/light/libxl_x86.c b/tools/libs/light/libxl_x86.c
index 5c4c194c65..91a9fc72ed 100644
--- a/tools/libs/light/libxl_x86.c
+++ b/tools/libs/light/libxl_x86.c
@@ -310,6 +310,7 @@ static int hvm_set_viridian_features(libxl__gc *gc, uint32_t domid,
         libxl_bitmap_set(&enlightenments, LIBXL_VIRIDIAN_ENLIGHTENMENT_APIC_ASSIST);
         libxl_bitmap_set(&enlightenments, LIBXL_VIRIDIAN_ENLIGHTENMENT_CRASH_CTL);
         libxl_bitmap_set(&enlightenments, LIBXL_VIRIDIAN_ENLIGHTENMENT_NO_VP_LIMIT);
+        libxl_bitmap_set(&enlightenments, LIBXL_VIRIDIAN_ENLIGHTENMENT_CPU_HOTPLUG);
     }
 
     libxl_for_each_set_bit(v, info->u.hvm.viridian_enable) {
@@ -373,6 +374,9 @@ static int hvm_set_viridian_features(libxl__gc *gc, uint32_t domid,
     if (libxl_bitmap_test(&enlightenments, LIBXL_VIRIDIAN_ENLIGHTENMENT_NO_VP_LIMIT))
         mask |= HVMPV_no_vp_limit;
 
+    if (libxl_bitmap_test(&enlightenments, LIBXL_VIRIDIAN_ENLIGHTENMENT_CPU_HOTPLUG))
+        mask |= HVMPV_cpu_hotplug;
+
     if (mask != 0 &&
         xc_hvm_param_set(CTX->xch,
                          domid,
diff --git a/xen/arch/x86/hvm/viridian/viridian.c b/xen/arch/x86/hvm/viridian/viridian.c
index ae1ea8630b..b906f7b86a 100644
--- a/xen/arch/x86/hvm/viridian/viridian.c
+++ b/xen/arch/x86/hvm/viridian/viridian.c
@@ -76,6 +76,7 @@ typedef union _HV_CRASH_CTL_REG_CONTENTS
 } HV_CRASH_CTL_REG_CONTENTS;
 
 /* Viridian CPUID leaf 3, Hypervisor Feature Indication */
+#define CPUID3D_CPU_DYNAMIC_PARTITIONING (1 << 3)
 #define CPUID3D_CRASH_MSRS (1 << 10)
 #define CPUID3D_SINT_POLLING (1 << 17)
 
@@ -179,8 +180,10 @@ void cpuid_viridian_leaves(const struct vcpu *v, uint32_t leaf,
         res->a = u.lo;
         res->b = u.hi;
 
+        if ( viridian_feature_mask(d) & HVMPV_cpu_hotplug )
+           res->d = CPUID3D_CPU_DYNAMIC_PARTITIONING;
         if ( viridian_feature_mask(d) & HVMPV_crash_ctl )
-            res->d = CPUID3D_CRASH_MSRS;
+            res->d |= CPUID3D_CRASH_MSRS;
         if ( viridian_feature_mask(d) & HVMPV_synic )
             res->d |= CPUID3D_SINT_POLLING;
 
diff --git a/xen/include/public/hvm/params.h b/xen/include/public/hvm/params.h
index 805f4ca44c..c9d6e70d7b 100644
--- a/xen/include/public/hvm/params.h
+++ b/xen/include/public/hvm/params.h
@@ -172,6 +172,10 @@
 #define _HVMPV_no_vp_limit 11
 #define HVMPV_no_vp_limit (1 << _HVMPV_no_vp_limit)
 
+/* Enable vCPU hotplug */
+#define _HVMPV_cpu_hotplug 12
+#define HVMPV_cpu_hotplug (1 << _HVMPV_cpu_hotplug)
+
 #define HVMPV_feature_mask \
         (HVMPV_base_freq | \
          HVMPV_no_freq | \
@@ -184,7 +188,8 @@
          HVMPV_stimer | \
          HVMPV_hcall_ipi | \
          HVMPV_ex_processor_masks | \
-         HVMPV_no_vp_limit)
+         HVMPV_no_vp_limit | \
+         HVMPV_cpu_hotplug)
 
 #endif