diff --git a/ChangeLog b/ChangeLog
index aee611641..ca8ea2e5d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2013-11-18  Josh Triplett  <josh@joshtriplett.org>
+
+	* grub-core/mmap/efi/mmap.c (grub_mmap_register): Round up/down to
+	4k page boundaries as expected by firmware rather than 1k
+	boundaries.
+	(grub_mmap_malign_and_register): Likewise.
+
 2013-11-18  Vladimir Serbinenko  <phcoder@gmail.com>
 
 	* tests/grub_func_test.in: Decrease RAM size to 512M. With less
diff --git a/grub-core/mmap/efi/mmap.c b/grub-core/mmap/efi/mmap.c
index 4f17c8b53..a77efe81d 100644
--- a/grub-core/mmap/efi/mmap.c
+++ b/grub-core/mmap/efi/mmap.c
@@ -184,8 +184,8 @@ grub_mmap_register (grub_uint64_t start, grub_uint64_t size, int type)
     return 0;
 
   b = grub_efi_system_table->boot_services;
-  address = start & (~0x3ffULL);
-  pages = (end - address  + 0x3ff) >> 12;
+  address = start & (~0xfffULL);
+  pages = (end - address + 0xfff) >> 12;
   status = efi_call_2 (b->free_pages, address, pages);
   if (status != GRUB_EFI_SUCCESS && status != GRUB_EFI_NOT_FOUND)
     {
@@ -263,7 +263,7 @@ grub_mmap_malign_and_register (grub_uint64_t align __attribute__ ((unused)),
   atype = GRUB_EFI_ALLOCATE_ANY_PAGES;
 #endif
 
-  pages = (size + 0x3ff) >> 12;
+  pages = (size + 0xfff) >> 12;
   status = efi_call_4 (b->allocate_pages, atype,
 		       make_efi_memtype (type), pages, &address);
   if (status != GRUB_EFI_SUCCESS)