x86: stricter check in follow_huge_addr()

The first page of the compound page is determined in follow_huge_addr()
but then PageCompound() only checks if the page is part of a compound page.
PageHead() allows checking if this is indeed the first page of the
compound.

Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 1 insertions, 1 deletions

diff --git a/arch/x86/mm/hugetlbpage.c b/arch/x86/mm/hugetlbpage.c
index 4fbafb4bc2f0..0b3d567e686d 100644
--- a/arch/x86/mm/hugetlbpage.c
+++ b/arch/x86/mm/hugetlbpage.c
@@ -178,7 +178,7 @@ follow_huge_addr(struct mm_struct *mm, unsigned long address, int write)
 
         page = &pte_page(*pte)[vpfn % (HPAGE_SIZE/PAGE_SIZE)];
 
-        WARN_ON(!PageCompound(page));
+        WARN_ON(!PageHead(page));
 
         return page;
 }