diff --git a/mm/highmem.c b/mm/highmem.c
index 2da13a5c50e2..2576a7118981 100644
--- a/mm/highmem.c
+++ b/mm/highmem.c
@@ -99,7 +99,7 @@ struct page *kmap_to_page(void *vaddr)
 	unsigned long addr = (unsigned long)vaddr;
 
 	if (addr >= PKMAP_ADDR(0) && addr < PKMAP_ADDR(LAST_PKMAP)) {
-		int i = (addr - PKMAP_ADDR(0)) >> PAGE_SHIFT;
+		int i = PKMAP_NR(addr);
 		return pte_page(pkmap_page_table[i]);
 	}