[MIPS] sparsemem: fix crash in show_mem

With sparsemem, pfn should be checked by pfn_valid() before pfn_to_page().

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/arch/mips/mm/pgtable.c b/arch/mips/mm/pgtable.c
index 792c6eb44232..c93aa6cbcaca 100644
--- a/arch/mips/mm/pgtable.c
+++ b/arch/mips/mm/pgtable.c
@@ -15,6 +15,8 @@ void show_mem(void)
         printk("Free swap:       %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
         pfn = max_mapnr;
         while (pfn-- > 0) {
+                if (!pfn_valid(pfn))
+                        continue;
                 page = pfn_to_page(pfn);
                 total++;
                 if (PageHighMem(page))