stop c_p_a corrupting the pds

When change_page_attr splits a large page on x86_32 (without PAE), it is
currently corrupting every process's page directory: fix that by removing
the thinko which passes down a physical instead of a virtual address.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/x86/mm/pageattr.c

@@ -237,7 +237,6 @@ static void __set_pmd_pte(pte_t *kpte, unsigned long address, pte_t pte)
 	if (!SHARED_KERNEL_PMD) {
 		struct page *page;
 
-		address = __pa(address);
 		list_for_each_entry(page, &pgd_list, lru) {
 			pgd_t *pgd;
 			pud_t *pud;