x86: reserve EFI memory map with reserve_early

This patch reserves the EFI memory map with reserve_early(). Because EFI
memory map is allocated by bootloader, if it is not reserved by
reserved_early(), it may be overwritten through address returned by
find_e820_area().

Signed-off-by: Huang Ying <ying.huang@intel.com>
Cc: andi@firstfloor.org
Cc: mingo@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/arch/x86/kernel/setup_32.c b/arch/x86/kernel/setup_32.c
index 0ec6480..2960cbe 100644
--- a/arch/x86/kernel/setup_32.c
+++ b/arch/x86/kernel/setup_32.c
@@ -67,6 +67,7 @@
 #include <asm/bios_ebda.h>
 #include <asm/cacheflush.h>
 #include <asm/processor.h>
+#include <asm/efi.h>
 
 /* This value is set up by the early boot code to point to the value
    immediately after the boot time page tables.  It contains a *physical*
@@ -683,8 +684,10 @@
 
 #ifdef CONFIG_EFI
 	if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
-		     "EL32", 4))
+		     "EL32", 4)) {
 		efi_enabled = 1;
+		efi_reserve_early();
+	}
 #endif
 
 	ROOT_DEV = old_decode_dev(boot_params.hdr.root_dev);