The dom0_ops implementation wasn't matching the interface definition,

leading to ill messages when X starts up (and potentially to other
problems). The attached patch fixes that. However, it also points out
that there is a potential disagreement between the dom0_ops interface
and the internal MTRR interface - the former expects an unsigned
register number from the domain, the latter wants a signed one and does
a lookup when it's negative. I would think that the lookup code should
just be ripped out of xen/arch/x86/mtrr/main.c.

Signed-off-by: Jan Beulich <JBeulich@novell.com>

diff --git a/xen/arch/x86/dom0_ops.c b/xen/arch/x86/dom0_ops.c
index 5a4f493ce0da517a69727e410225cee923a02edc..9a3922f967b94f2a0e3f3e91f9079f961842f525 100644 (file)
--- a/xen/arch/x86/dom0_ops.c
+++ b/xen/arch/x86/dom0_ops.c
@@ -103,12 +103,27 @@ long arch_do_dom0_op(dom0_op_t *op, dom0_op_t *u_dom0_op)
             op->u.add_memtype.nr_pfns,
             op->u.add_memtype.type,
             1);
+        if (ret > 0)
+        {
+            (void)__put_user(0, &u_dom0_op->u.add_memtype.handle);
+            (void)__put_user(ret, &u_dom0_op->u.add_memtype.reg);
+            ret = 0;
+        }
     }
     break;
 
     case DOM0_DEL_MEMTYPE:
     {
-        ret = mtrr_del_page(op->u.del_memtype.reg, 0, 0);
+        if (op->u.del_memtype.handle == 0
+            /* mtrr/main.c otherwise does a lookup */
+            && (int)op->u.del_memtype.reg >= 0)
+        {
+            ret = mtrr_del_page(op->u.del_memtype.reg, 0, 0);
+            if (ret > 0)
+                ret = 0;
+        }
+        else
+            ret = -EINVAL;
     }
     break;
 
@@ -179,7 +194,7 @@ long arch_do_dom0_op(dom0_op_t *op, dom0_op_t *u_dom0_op)
         memcpy(pi->hw_cap, boot_cpu_data.x86_capability, NCAPINTS*4);
         ret = 0;
         if ( copy_to_user(u_dom0_op, op, sizeof(*op)) )
-           ret = -EFAULT;
+            ret = -EFAULT;
     }
     break;