diff --git a/tools/libs/light/libxl_create.c b/tools/libs/light/libxl_create.c
index edeadd57ef..569e3d21ed 100644
--- a/tools/libs/light/libxl_create.c
+++ b/tools/libs/light/libxl_create.c
@@ -680,17 +680,17 @@ int libxl__domain_make(libxl__gc *gc, libxl_domain_config *d_config,
         LOG(DETAIL, "altp2m: %s", libxl_altp2m_mode_to_string(b_info->altp2m));
         switch(b_info->altp2m) {
         case LIBXL_ALTP2M_MODE_MIXED:
-            create.altp2m_opts |=
+            create.altp2m.opts |=
                 XEN_DOMCTL_ALTP2M_mode(XEN_DOMCTL_ALTP2M_mixed);
             break;

         case LIBXL_ALTP2M_MODE_EXTERNAL:
-            create.altp2m_opts |=
+            create.altp2m.opts |=
                 XEN_DOMCTL_ALTP2M_mode(XEN_DOMCTL_ALTP2M_external);
             break;

         case LIBXL_ALTP2M_MODE_LIMITED:
-            create.altp2m_opts |=
+            create.altp2m.opts |=
                 XEN_DOMCTL_ALTP2M_mode(XEN_DOMCTL_ALTP2M_limited);
             break;

diff --git a/tools/ocaml/libs/xc/xenctrl_stubs.c b/tools/ocaml/libs/xc/xenctrl_stubs.c
index a529080129..e6c977521f 100644
--- a/tools/ocaml/libs/xc/xenctrl_stubs.c
+++ b/tools/ocaml/libs/xc/xenctrl_stubs.c
@@ -231,7 +231,9 @@ CAMLprim value stub_xc_domain_create(value xch_val, value wanted_domid, value co
 		.max_maptrack_frames = Int_val(VAL_MAX_MAPTRACK_FRAMES),
 		.grant_opts =
 		    XEN_DOMCTL_GRANT_version(Int_val(VAL_MAX_GRANT_VERSION)),
-		.altp2m_opts = Int32_val(VAL_ALTP2M_OPTS),
+		.altp2m = {
+			.opts = Int32_val(VAL_ALTP2M_OPTS),
+		},
 		.vmtrace_size = vmtrace_size,
 		.cpupool_id = Int32_val(VAL_CPUPOOL_ID),
 	};
diff --git a/xen/arch/arm/domain.c b/xen/arch/arm/domain.c
index 8bde2f730d..5234b627d0 100644
--- a/xen/arch/arm/domain.c
+++ b/xen/arch/arm/domain.c
@@ -688,7 +688,7 @@ int arch_sanitise_domain_config(struct xen_domctl_createdomain *config)
         return -EINVAL;
     }

-    if ( config->altp2m_opts )
+    if ( config->altp2m.opts )
     {
         dprintk(XENLOG_INFO, "Altp2m not supported\n");
         return -EINVAL;
diff --git a/xen/arch/x86/domain.c b/xen/arch/x86/domain.c
index 536542841e..bb5ba8fc1e 100644
--- a/xen/arch/x86/domain.c
+++ b/xen/arch/x86/domain.c
@@ -637,7 +637,7 @@ int arch_sanitise_domain_config(struct xen_domctl_createdomain *config)
     bool hap = config->flags & XEN_DOMCTL_CDF_hap;
     bool nested_virt = config->flags & XEN_DOMCTL_CDF_nested_virt;
     unsigned int max_vcpus;
-    unsigned int altp2m_mode = MASK_EXTR(config->altp2m_opts,
+    unsigned int altp2m_mode = MASK_EXTR(config->altp2m.opts,
                                          XEN_DOMCTL_ALTP2M_mode_mask);

     if ( hvm ? !hvm_enabled : !IS_ENABLED(CONFIG_PV) )
@@ -717,7 +717,7 @@ int arch_sanitise_domain_config(struct xen_domctl_createdomain *config)
         return -EINVAL;
     }

-    if ( config->altp2m_opts & ~XEN_DOMCTL_ALTP2M_mode_mask )
+    if ( config->altp2m.opts & ~XEN_DOMCTL_ALTP2M_mode_mask )
     {
         dprintk(XENLOG_INFO, "Invalid altp2m options selected: %#x\n",
                 config->flags);
diff --git a/xen/arch/x86/hvm/hvm.c b/xen/arch/x86/hvm/hvm.c
index 8334ab1711..a66ebaaceb 100644
--- a/xen/arch/x86/hvm/hvm.c
+++ b/xen/arch/x86/hvm/hvm.c
@@ -659,7 +659,7 @@ int hvm_domain_initialise(struct domain *d,
     d->arch.hvm.params[HVM_PARAM_TRIPLE_FAULT_REASON] = SHUTDOWN_reboot;

     /* Set altp2m based on domctl flags. */
-    switch ( MASK_EXTR(config->altp2m_opts, XEN_DOMCTL_ALTP2M_mode_mask) )
+    switch ( MASK_EXTR(config->altp2m.opts, XEN_DOMCTL_ALTP2M_mode_mask) )
     {
     case XEN_DOMCTL_ALTP2M_mixed:
         d->arch.hvm.params[HVM_PARAM_ALTP2M] = XEN_ALTP2M_mixed;
diff --git a/xen/include/public/domctl.h b/xen/include/public/domctl.h
index 2a49fe46ce..dea399aa8e 100644
--- a/xen/include/public/domctl.h
+++ b/xen/include/public/domctl.h
@@ -86,6 +86,7 @@ struct xen_domctl_createdomain {

     uint32_t grant_opts;

+    struct {
 /*
  * Enable altp2m mixed mode.
  *
@@ -102,7 +103,8 @@ struct xen_domctl_createdomain {
 /* Altp2m mode signaling uses bits [0, 1]. */
 #define XEN_DOMCTL_ALTP2M_mode_mask  (0x3U)
 #define XEN_DOMCTL_ALTP2M_mode(m)    ((m) & XEN_DOMCTL_ALTP2M_mode_mask)
-    uint32_t altp2m_opts;
+        uint32_t opts;
+    } altp2m;

     /* Per-vCPU buffer size in bytes.  0 to disable. */
     uint32_t vmtrace_size;
