From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pd0-f178.google.com (mail-pd0-f178.google.com [209.85.192.178]) by kanga.kvack.org (Postfix) with ESMTP id 4B8E26B0082 for ; Tue, 28 Apr 2015 12:25:10 -0400 (EDT) Received: by pdbqa5 with SMTP id qa5so64414pdb.1 for ; Tue, 28 Apr 2015 09:25:10 -0700 (PDT) Received: from mga03.intel.com (mga03.intel.com. [134.134.136.65]) by mx.google.com with ESMTP id pg3si35366967pdb.124.2015.04.28.09.25.08 for ; Tue, 28 Apr 2015 09:25:08 -0700 (PDT) From: "Kirill A. Shutemov" Subject: [PATCH 0/2] Reintroduce picky __compound_tail_refcounted() Date: Tue, 28 Apr 2015 19:24:56 +0300 Message-Id: <1430238298-80442-1-git-send-email-kirill.shutemov@linux.intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrea Arcangeli , Borislav Petkov , Hugh Dickins , Linus Torvalds , "Kirill A. Shutemov" Hi Andrew, My patch 8d63d99a5dfb which was merged during 4.1 merge window caused regression: page:ffffea0010a15040 count:0 mapcount:1 mapping: (null) index:0x0 flags: 0x8000000000008014(referenced|dirty|tail) page dumped because: VM_BUG_ON_PAGE(page_mapcount(page) != 0) ------------[ cut here ]------------ kernel BUG at mm/swap.c:134! The patch was reverted by Linus. This VM_BUG_ON_PAGE() is bogus. The first patch explains why the assert is wrong and removes it. The second re-introduces original patch. Kirill A. Shutemov (2): mm: drop bogus VM_BUG_ON_PAGE assert in put_page() codepath mm: avoid tail page refcounting on non-THP compound pages include/linux/mm.h | 2 +- mm/swap.c | 1 - 2 files changed, 1 insertion(+), 2 deletions(-) -- 2.1.4 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org