hugetlb: fix clear_user_highpage arguments

The virtual address space argument of clear_user_highpage is supposed to be
the virtual address where the page being cleared will eventually be mapped.
 This allows architectures with virtually indexed caches a few clever
tricks.  That sort of trick falls over in painful ways if the virtual
address argument is wrong.

Signed-off-by: Ralf Baechle <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

mm/hugetlb.c

@@ -42,7 +42,7 @@ static void clear_huge_page(struct page *page, unsigned long addr)
 	might_sleep();
 	for (i = 0; i < (HPAGE_SIZE/PAGE_SIZE); i++) {
 		cond_resched();
-		clear_user_highpage(page + i, addr);
+		clear_user_highpage(page + i, addr + i * PAGE_SIZE);
 	}
 }