mmap and ppc460gt

[Roland Dreier]

OK, please try this and let me know if it helps:

diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index 1c93c25..98d7bf9 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -75,11 +75,10 @@ static inline pte_t *virt_to_kpte(unsigned long vaddr)
 
 int page_is_ram(unsigned long pfn)
 {
-	unsigned long paddr = (pfn << PAGE_SHIFT);
-
 #ifndef CONFIG_PPC64	/* XXX for now */
-	return paddr < __pa(high_memory);
+	return pfn < max_pfn;
 #else
+	unsigned long paddr = (pfn << PAGE_SHIFT);
 	int i;
 	for (i=0; i < lmb.memory.cnt; i++) {
 		unsigned long base;