diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index d7aea41..7d7a36d 100644
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -45,11 +45,15 @@
 	int i;
 	unsigned long puds = 0, pmds = 0, ptes = 0, tables;
 	unsigned long start = 0, good_end;
+	unsigned long pgd_extra = 0;
 	phys_addr_t base;
 
 	for (i = 0; i < nr_range; i++) {
 		unsigned long range, extra;
 
+		if ((mr[i].end >> PGDIR_SHIFT) - (mr[i].start >> PGDIR_SHIFT))
+			pgd_extra++;
+
 		range = mr[i].end - mr[i].start;
 		puds += (range + PUD_SIZE - 1) >> PUD_SHIFT;
 
@@ -74,6 +78,7 @@
 	tables = roundup(puds * sizeof(pud_t), PAGE_SIZE);
 	tables += roundup(pmds * sizeof(pmd_t), PAGE_SIZE);
 	tables += roundup(ptes * sizeof(pte_t), PAGE_SIZE);
+	tables += (pgd_extra * PAGE_SIZE);
 
 #ifdef CONFIG_X86_32
 	/* for fixmap */