xen: make sure xen_extra_mem_start is beyond all non-RAM e820

If Xen gives us non-RAM E820 entries (dom0 only, typically), then
make sure the extra RAM region is beyond them.  It's OK for
the extra space to grow into E820 regions, however.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index f9a99eaddcdc..eac010008cd2 100644
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -167,7 +167,8 @@ char * __init xen_memory_setup(void)
 
                                 extra_pages += PFN_DOWN(end - mem_end);
                         }
-                }
+                } else if (map[i].type != E820_RAM)
+                        xen_extra_mem_start = end;
                 if (map[i].size > 0)
                         e820_add_region(map[i].addr, map[i].size, map[i].type);
         }