On Tue, 11 Aug 2015 18:47:57 +0800 Wanpeng Li <wanpeng.li@xxxxxxxxxxx> wrote: > > ... > > Huge zero page is allocated if page fault w/o FAULT_FLAG_WRITE flag. > The get_user_pages_fast() which called in madvise_hwpoison() will get > huge zero page if the page is not allocated before. Huge zero page is > a tranparent huge page, however, it is not an anonymous page. memory_failure > will split the huge zero page and trigger BUG_ON(is_huge_zero_page(page)); > After commit (98ed2b0: mm/memory-failure: give up error handling for > non-tail-refcounted thp), memory_failure will not catch non anon thp > from madvise_hwpoison path and this bug occur. So I'm assuming this patch is needed for 4.2 but not in earlier kernels. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>