diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index acabc856fe8a..0d1a65879a35 100644
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -667,13 +667,13 @@ static __init int match_config_table(const efi_guid_t *guid,
 
 static __init void reserve_unaccepted(struct efi_unaccepted_memory *unaccepted)
 {
-	phys_addr_t start, size;
+	phys_addr_t start, end;
 
 	start = PAGE_ALIGN_DOWN(efi.unaccepted);
-	size = PAGE_ALIGN(sizeof(*unaccepted) + unaccepted->size);
+	end = PAGE_ALIGN(efi.unaccepted + sizeof(*unaccepted) + unaccepted->size);
 
-	memblock_add(start, size);
-	memblock_reserve(start, size);
+	memblock_add(start, end - start);
+	memblock_reserve(start, end - start);
 }
 
 int __init efi_config_parse_tables(const efi_config_table_t *config_tables,