[PATCH] x86: fix EFI memory map parsing

The memory descriptors that comprise the EFI memory map are not fixed in
stone such that the size could change in the future.  This uses the memory
descriptor size obtained from EFI to iterate over the memory map entries
during boot.  This enables the removal of an x86 specific pad (and ifdef)
in the EFI header.  I also couldn't stomach the broken up nature of the
function to put EFI runtime calls into virtual mode any longer so I fixed
that up a bit as well.

For reference, this patch only impacts x86.

Signed-off-by: Matt Tolentino <matthew.e.tolentino@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 3 insertions, 2 deletions

diff --git a/arch/i386/mm/init.c b/arch/i386/mm/init.c
index 12216b52e28b..d8b23ab76533 100644
--- a/arch/i386/mm/init.c
+++ b/arch/i386/mm/init.c
@@ -198,9 +198,10 @@ int page_is_ram(unsigned long pagenr)
 
         if (efi_enabled) {
                 efi_memory_desc_t *md;
+                void *p;
 
-                for (i = 0; i < memmap.nr_map; i++) {
-                        md = &memmap.map[i];
+                for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
+                        md = p;
                         if (!is_available_memory(md))
                                 continue;
                         addr = (md->phys_addr+PAGE_SIZE-1) >> PAGE_SHIFT;