[SPARC64]: Align address in huge_pte_alloc().

We are about to fill in all HPAGE_SIZE's worth
of PAGE_SIZE ptes, so we have to give the first
pte in that set else we scribble over random memory
when we fill in the ptes.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 7 insertions, 0 deletions

diff --git a/arch/sparc64/mm/hugetlbpage.c b/arch/sparc64/mm/hugetlbpage.c
index 074620d413d4..fbbbebbad8a4 100644
--- a/arch/sparc64/mm/hugetlbpage.c
+++ b/arch/sparc64/mm/hugetlbpage.c
@@ -198,6 +198,13 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr)
         pmd_t *pmd;
         pte_t *pte = NULL;
 
+        /* We must align the address, because our caller will run
+         * set_huge_pte_at() on whatever we return, which writes out
+         * all of the sub-ptes for the hugepage range.  So we have
+         * to give it the first such sub-pte.
+         */
+        addr &= HPAGE_MASK;
+
         pgd = pgd_offset(mm, addr);
         pud = pud_alloc(mm, pgd, addr);
         if (pud) {