References: CVE-2013-0154 XSA-37 bnc#797031

# HG changeset patch
# User Jan Beulich <jbeulich@suse.com>
# Date 1357564826 -3600
# Node ID e1facbde56ff4e5e85f9a4935abc99eb24367cd0
# Parent  8e942f2f3b45edc5bb1f7a6e05de288342426f0d
x86: fix assertion in get_page_type()

c/s 22998:e9fab50d7b61 (and immediately following ones) made it
possible that __get_page_type() returns other than -EINVAL, in
particular -EBUSY. Consequently, the assertion in get_page_type()
should check for only the return values we absolutely don't expect to
see there.

This is XSA-37 / CVE-2013-0154.

Signed-off-by: Jan Beulich <jbeulich@suse.com>

--- a/xen/arch/x86/mm.c
+++ b/xen/arch/x86/mm.c
@@ -2603,7 +2603,7 @@ int get_page_type(struct page_info *page
     int rc = __get_page_type(page, type, 0);
     if ( likely(rc == 0) )
         return 1;
-    ASSERT(rc == -EINVAL);
+    ASSERT(rc != -EINTR && rc != -EAGAIN);
     return 0;
 }