merge mainline into backtrace

diff --cc grub-core/Makefile.core.def
index 64298cf,cae79b3..003041f
--- 1/grub-core/Makefile.core.def
--- 2/grub-core/Makefile.core.def
+++ b/grub-core/Makefile.core.def
@@@ -1432,7 -1709,35 +1709,41 @@@ module = 
    common = commands/testload.c;
  };
  
 +module = {
 +  name = backtrace;
 +  common = lib/i386/backtrace.c lib/i386/backtrace_int.S;
++  enable = i386;
++};
++
+ module = {
+   name = lsapm;
+   common = commands/i386/pc/lsapm.c;
+   enable = i386_pc;
+ };
+ 
+ module = {
+   name = keylayouts;
+   common = commands/keylayouts.c;
+   enable = videomodules;
+ };
+ 
+ module = {
+   name = time;
+   common = commands/time.c;
+ };
+ 
+ module = {
+   name = cacheinfo;
+   common = commands/cacheinfo.c;
+   condition = COND_ENABLE_CACHE_STATS;
+ };
+ 
+ module = {
+   name = adler32;
+   common = lib/adler32.c;
+ };
+ 
+ module = {
+   name = crc64;
+   common = lib/crc64.c;
  };

diff --cc grub-core/kern/i386/realmode.S
index ffba6db,2e16847..ecfdf4f
--- 1/grub-core/kern/i386/realmode.S
--- 2/grub-core/kern/i386/realmode.S
+++ b/grub-core/kern/i386/realmode.S
@@@ -166,11 -168,27 +174,30 @@@ protcseg
        /* zero %eax */
        xorl    %eax, %eax
  
 +      sidt realidt
 +      lidt protidt
 +
        /* return on the old (or initialized) stack! */
        ret
+ /*
+  *  GRUB  --  GRand Unified Bootloader
+  *  Copyright (C) 1999,2000,2001,2002,2003,2005,2006,2007,2009,2010 Free Software Foundation, Inc.
+  *
+  *  GRUB is free software: you can redistribute it and/or modify
+  *  it under the terms of the GNU General Public License as published by
+  *  the Free Software Foundation, either version 3 of the License, or
+  *  (at your option) any later version.
+  *
+  *  GRUB is distributed in the hope that it will be useful,
+  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  *  GNU General Public License for more details.
+  *
+  *  You should have received a copy of the GNU General Public License
+  *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
+  */
+ 
+ #include <grub/i386/pc/memory.h>
  
  prot_to_real:
        /* just in case, set GDT */