From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030514AbbD1QZL (ORCPT ); Tue, 28 Apr 2015 12:25:11 -0400 Received: from mga11.intel.com ([192.55.52.93]:47026 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030209AbbD1QZJ (ORCPT ); Tue, 28 Apr 2015 12:25:09 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.11,664,1422950400"; d="scan'208";a="686957752" From: "Kirill A. Shutemov" To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrea Arcangeli , Borislav Petkov , Hugh Dickins , Linus Torvalds , "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> X-Mailer: git-send-email 2.1.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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