[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>

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) {