diff -r bc9b31af8865 tools/libxc/xc_domain_save.c
--- a/tools/libxc/xc_domain_save.c	Mon Nov 08 15:13:56 2010 -0500
+++ b/tools/libxc/xc_domain_save.c	Mon Nov 08 15:26:34 2010 -0500
@@ -827,7 +827,9 @@ static xen_pfn_t *map_and_save_p2m_table
         }
         xcnt_size = domctl.u.vcpuextstate.size + 2 * sizeof(uint64_t);
 
-        tot_sz = (chunk1_sz + 8) + (chunk2_sz + 8) + (chunk3_sz + 8);
+        tot_sz = (chunk1_sz + 8) + (chunk2_sz + 8);
+        if ( domctl.u.vcpuextstate.xfeature_mask )
+            tot_sz += chunk3_sz + 8;
 
         if ( write_exact(io_fd, &signature, sizeof(signature)) ||
              write_exact(io_fd, &tot_sz, sizeof(tot_sz)) ||
@@ -836,9 +838,11 @@ static xen_pfn_t *map_and_save_p2m_table
              write_exact(io_fd, &ctxt, chunk1_sz) ||
              write_exact(io_fd, "extv", 4) ||
              write_exact(io_fd, &chunk2_sz, sizeof(chunk2_sz)) ||
-             write_exact(io_fd, "xcnt", 4) ||
-             write_exact(io_fd, &chunk3_sz, sizeof(chunk3_sz)) ||
-             write_exact(io_fd, &xcnt_size, 4) )
+             (domctl.u.vcpuextstate.xfeature_mask) ?
+                (write_exact(io_fd, "xcnt", 4) ||
+                write_exact(io_fd, &chunk3_sz, sizeof(chunk3_sz)) ||
+                write_exact(io_fd, &xcnt_size, 4)) :
+                0 )
         {
             PERROR("write: extended info");
             goto out;
@@ -1824,6 +1828,9 @@ int xc_domain_save(xc_interface *xch, in
             goto out;
         }
 
+        if ( !domctl.u.vcpuextstate.xfeature_mask )
+            continue;
+
         /* Getting eXtended states data */
         buffer = xc_hypercall_buffer_alloc(xch, buffer, domctl.u.vcpuextstate.size);
         if ( !buffer )
@@ -1836,24 +1843,18 @@ int xc_domain_save(xc_interface *xch, in
         if ( xc_domctl(xch, &domctl) < 0 )
         {
             PERROR("No eXtended states (XSAVE) for VCPU%d", i);
+            xc_hypercall_buffer_free(xch, buffer);
             goto out;
         }
 
         if ( wrexact(io_fd, &domctl.u.vcpuextstate.xfeature_mask,
-                     sizeof(domctl.u.vcpuextstate.xfeature_mask)) )
-        {
-            PERROR("Error when writing to state file (2)");
-            goto out;
-        }
-        if ( wrexact(io_fd, &domctl.u.vcpuextstate.size,
-                     sizeof(domctl.u.vcpuextstate.size)) )
-        {
-            PERROR("Error when writing to state file (2)");
-            goto out;
-        }
-        if ( wrexact(io_fd, buffer, domctl.u.vcpuextstate.size) )
-        {
-            PERROR("Error when writing to state file (2)");
+                     sizeof(domctl.u.vcpuextstate.xfeature_mask)) ||
+             wrexact(io_fd, &domctl.u.vcpuextstate.size,
+                     sizeof(domctl.u.vcpuextstate.size)) ||
+             wrexact(io_fd, buffer, domctl.u.vcpuextstate.size) )
+        {
+            PERROR("Error when writing to state file VCPU extended state");
+            xc_hypercall_buffer_free(xch, buffer);
             goto out;
         }
         xc_hypercall_buffer_free(xch, buffer);
diff -r bc9b31af8865 xen/arch/x86/domctl.c
--- a/xen/arch/x86/domctl.c	Mon Nov 08 15:13:56 2010 -0500
+++ b/xen/arch/x86/domctl.c	Mon Nov 08 15:14:50 2010 -0500
@@ -1424,9 +1424,6 @@ long arch_do_domctl(
 
         ret = -ESRCH;
 
-        if ( !cpu_has_xsave )
-            break;
-
         d = rcu_lock_domain_by_id(domctl->domain);
         if ( d == NULL )
             break;