diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index 57120f0749cc..c32ef7f5205f 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -753,20 +753,20 @@ void __init e820__memory_setup_extended(u64 phys_addr, u32 data_len)
 void __init e820__register_nosave_regions(unsigned long limit_pfn)
 {
 	int i;
-	unsigned long pfn = 0;
+	u64 last_addr = 0;
 
 	for (i = 0; i < e820_table->nr_entries; i++) {
 		struct e820_entry *entry = &e820_table->entries[i];
 
-		if (pfn < PFN_UP(entry->addr))
-			register_nosave_region(pfn, PFN_UP(entry->addr));
+		if (last_addr < entry->addr)
+			register_nosave_region(PFN_UP(last_addr), PFN_DOWN(entry->addr));
 
-		pfn = PFN_DOWN(entry->addr + entry->size);
+		last_addr = entry->addr + entry->size;
 
 		if (entry->type != E820_TYPE_RAM)
-			register_nosave_region(PFN_UP(entry->addr), pfn);
+			register_nosave_region(PFN_UP(entry->addr), PFN_DOWN(last_addr));
 
-		if (pfn >= limit_pfn)
+		if (PFN_DOWN(last_addr) >= limit_pfn)
 			break;
 	}
 }