During showing the pagetypeinfo, we forgot to save the found page and dereference a invalid page address from the stack.
To fix it, save and reference the page address returned by pfn_to_online_page(). Signed-off-by: Firo Yang <[email protected]> --- mm/vmstat.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/mm/vmstat.c b/mm/vmstat.c index c432e58..6dae6b2 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -1223,7 +1223,8 @@ static void pagetypeinfo_showblockcount_print(struct seq_file *m, for (pfn = start_pfn; pfn < end_pfn; pfn += pageblock_nr_pages) { struct page *page; - if (!pfn_to_online_page(pfn)) + page = pfn_to_online_page(pfn); + if (!page) continue; /* Watch for unexpected holes punched in the memmap */ -- 2.9.4
