xen: reserve Xen-specific memory in e820 map

Make sure that the start_info and pfn->mfn translation array are reserved.

---
arch/x86/xen/setup.c | 13 +++++++++++++

1 file changed, 13 insertions(+)

===================================================================

@@ -40,8 +40,21 @@

	max_pfn = min(MAX_DOMAIN_PAGES, max_pfn);

	e820.nr_map = 0;
+
	e820_add_region(0, LOWMEMSIZE(), E820_RAM);
	e820_add_region(HIGH_MEMORY, PFN_PHYS(max_pfn)-HIGH_MEMORY, E820_RAM);

+
+ /*
+ * Reserve Xen bits:
+ * - mfn_list
+ * - xen_start_info
+ * See comment above "struct start_info" in <xen/interface/xen.h>
+ */
+ e820_add_region(__pa(xen_start_info->mfn_list),
+ xen_start_info->pt_base - xen_start_info->mfn_list,
+ E820_RESERVED);
+
+ sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);

	return "Xen";
}